RU2827350C2 - Drug delivery system drive assembly - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention refers to medical equipment, namely to injection systems. Drug delivery system for drug injection comprises a drive assembly for the drug delivery system, which includes a plunger element. Plunger element is configured to engage and move the plug inside the container. Plunger element has a first position and a second position axially spaced from the first position. Lead screw is configured to move the plunger element from the first position to the second position. Displacing element is made with possibility of displacement of the lead screw in the direction of rotation. Rotary movement of the lead screw is configured to move the plunger element from the first position to the second position.

EFFECT: invention can be used to deliver fluid into patient’s body by injection.

5 cl, 100 dwg

Description

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to U.S. Provisional Patent Application No. 62/347,899, filed June 9, 2016, and U.S. Provisional Patent Application No. 15/616,162, filed June 7, 2017, each of which is incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

Field of technology to which the invention relates

[0002] The present invention relates generally to an injector device and method for delivering a fluid into a patient's body by injection.

Description of the Prior Art

[0003] Various types of automatic injection devices are designed to enable untrained personnel or self-administered medicinal solutions and other liquid medicinal preparations. In general, the mentioned devices include a reservoir that is pre-filled with a liquid medicinal preparation, and some type of mechanism for automatic injection through a needle that can be activated by the user. When the volume of fluid or drug to be administered is generally below a certain volume, such as 1 ml, an automatic injector is usually used, the injection time of which is usually approximately 10 to 15 seconds. When the volume of fluid or drug to be administered exceeds 1 ml, the injection time is usually increased, as a result of which it is more difficult for the patient to withstand the contact between the device and the target area of the patient's skin. In addition, when the volume of fluid or drug to be administered becomes larger, an increase in the injection time is desirable. A traditional method for a slow injection of a drug into a patient is to start the injection intravenously and slowly inject the drug into the patient. This procedure is usually performed in a hospital or outpatient clinic.

[0004] Some devices allow for self-injection at home and are capable of gradually injecting a liquid medication into the patient's skin. In some cases, these devices are small enough (both in height and in size) to be "worn" by the patient while the liquid medication is being infused into the patient. These devices typically include a pump or other type of pressure mechanism to cause the liquid medication to flow from a reservoir into an injection needle. These devices typically also include a valve or flow control mechanism to initiate the flow of the liquid medication at the proper time and a trigger mechanism to initiate the injection.

ESSENCE OF THE INVENTION

[0005] In one aspect, a drive assembly for a drug delivery system includes a plunger element configured to engage and move a stopper within a container, wherein the plunger element has a first position and a second position axially spaced from the first position, a lead screw configured to move the plunger element from the first position to the second position, and a biasing element configured to bias the lead screw in a rotational direction, wherein the rotational movement of the lead screw is configured to move the plunger element from the first position to the second position.

[0006] The biasing element may be a constant-rate spring. The lead screw may include a drum portion and a screw portion extending from the drum portion, wherein the biasing element is received in the drum portion. The drive unit may include a drive nut located on the lead screw, wherein the drive nut is configured to engage the plunger element to move the plunger element from the first position to the second position. The plunger element may include an outer plunger and an inner plunger movable relative to the outer plunger, wherein at least a portion of the inner plunger is received inside the outer plunger when the plunger element is in the first position. A leading element may be located on the lead screw, and the leading element may be configured to engage and axially move the outer plunger, wherein the axial movement of the outer plunger is configured to provide axial movement of the inner plunger. The outer plunger may include a threaded section configured to engage the leading element.

[0007] According to a further aspect, a drug delivery system for injecting a drug includes a container configured to contain a drug, wherein the container includes a plug configured to move within the container and a lid, and a drive unit includes a plunger element configured to engage and move the plug within the container. The plunger element has a first position and a second position axially spaced from the first position. The drive unit also includes a constant spring configured to move the plunger element from the first position to the second position. The system also includes a needle drive unit comprising a needle configured to be set in a state of fluid communication with the container, wherein the needle is movable from the first position to the second position, and the second position is spaced from the first position.

[0008] The system may include a lead screw engaged with a plunger element, and a constant spring may be configured to bias the lead screw in the direction of rotation, wherein the rotational movement of the lead screw causes an axial displacement of the plunger element from the first position to the second position. The lead screw may include a drum portion and a screw portion extending from the drum portion, wherein the constant spring is received and engaged with the drum portion. The system may include a drive nut located on the lead screw, wherein the drive nut is configured to engage the plunger element to move the plunger element from the first position to the second position. The plunger element may include an outer plunger and an inner plunger movable relative to the outer plunger, wherein at least a portion of the inner plunger is accommodated inside the outer plunger when the plunger element is in the first position. A leading element may be located on the lead screw, and the leading element may be configured to engage and axially move the outer plunger, wherein the axial movement of the outer plunger is configured to provide axial movement of the inner plunger. The outer plunger may include a threaded portion configured to engage the leading element.

BRIEF DESCRIPTION OF DRAWINGS

[0009] The above and other features and advantages of the present invention and the method of obtaining them will become apparent, and the invention itself will be better understood, by reference to the following descriptions of embodiments of the invention taken in connection with the accompanying drawings, in which:

[0010] Fig. 1 is a perspective view of a drug delivery system in accordance with one aspect of the present invention.

[0011] Fig. 2 is a perspective cross-sectional view of the drug delivery system shown in Fig. 1 in accordance with one aspect of the present invention.

[0012] Fig. 3 is a front cross-sectional view of the drug delivery system shown in Fig. 1, in accordance with one aspect of the present invention.

[0013] Fig. 4 is a top view of the drug delivery system shown in Fig. 1 in accordance with one aspect of the present invention, showing the top portion of the housing removed and the drug delivery system in position prior to use.

[0014] Fig. 5 is a top cross-sectional view of the drug delivery system shown in Fig. 1, in accordance with one aspect of the present invention, showing the drug delivery system in a position prior to use.

[0015] Fig. 6 is a front cross-sectional view of the drug delivery system shown in Fig. 1, in accordance with one aspect of the present invention, showing the drug delivery system in a position prior to use.

[0016] Fig. 7 is a top view of the drug delivery system shown in Fig. 1 in accordance with one aspect of the present invention, showing the top portion of the housing removed and the drug delivery system in a pre-fire position.

[0017] Fig. 8 is a top cross-sectional view of the drug delivery system shown in Fig. 1, in accordance with one aspect of the present invention, showing the drug delivery system in a pre-actuation position.

[0018] Fig. 9 is a front cross-sectional view of the drug delivery system shown in Fig. 1, in accordance with one aspect of the present invention, showing the drug delivery system in a pre-actuation position.

[0019] Fig. 10 is a top view of the drug delivery system shown in Fig. 1 in accordance with one aspect of the present invention, showing the top portion of the housing removed and the drug delivery system in a position of use.

[0020] Fig. 11 is a top cross-sectional view of the drug delivery system shown in Fig. 1, in accordance with one aspect of the present invention, showing the drug delivery system in a position of use.

[0021] Fig. 12 is a front cross-sectional view of the drug delivery system shown in Fig. 1, in accordance with one aspect of the present invention, showing the drug delivery system in a position of use.

[0022] Fig. 13 is a top view of the drug delivery system shown in Fig. 1 in accordance with one aspect of the present invention, showing the top portion of the housing removed and the drug delivery system in position after use.

[0023] Fig. 14 is a top cross-sectional view of the drug delivery system shown in Fig. 1, in accordance with one aspect of the present invention, showing the drug delivery system in a position after use.

[0024] Fig. 15 is a front cross-sectional view of the drug delivery system shown in Fig. 1, in accordance with one aspect of the present invention, showing the drug delivery system in a position after use.

[0025] Fig. 15A is a front cross-sectional view of the drug delivery system shown in Fig. 1, in accordance with one aspect of the present invention, showing the drug delivery system pad in position prior to use.

[0026] Fig. 15B is a perspective cross-sectional view of the drug delivery system shown in Fig. 1, in accordance with one aspect of the present invention, showing the drug delivery system pad in position prior to use.

[0027] Fig. 15C is a perspective cross-sectional view of the drug delivery system shown in Fig. 1, in accordance with one aspect of the present invention, showing the drug delivery system pad in position prior to use.

[0028] Fig. 16 is a partial cross-sectional view of the drug delivery system shown in Fig. 1, in accordance with one aspect of the present invention, showing the valve assembly.

[0029] Fig. 17 is a perspective view of a drive assembly for a drug delivery system in accordance with one aspect of the present invention.

[0030] Fig. 18 is a sectional view of the drive assembly shown in Fig. 17, in accordance with one aspect of the present invention, showing a position prior to use of the drive assembly.

[0031] Fig. 19 is a sectional view of the drive assembly shown in Fig. 17, in accordance with one aspect of the present invention, showing a position of use of the drive assembly.

[0032] Fig. 20 is a sectional view of the drive assembly shown in Fig. 17, in accordance with one aspect of the present invention, showing a position after use of the drive assembly.

[0033] Fig. 21 is a perspective view of a plunger drive element of the drive assembly shown in Fig. 17, in accordance with one aspect of the present invention.

[0034] Fig. 22 is a perspective view of the first plunger member of the drive assembly shown in Fig. 17, in accordance with one aspect of the present invention.

[0035] Fig. 23 is a perspective view of the plunger drive member and the first plunger member of the drive assembly shown in Fig. 17, in accordance with one aspect of the present invention, showing the plunger drive member in engagement with the first plunger member.

[0036] Fig. 24 is a perspective view of the plunger drive member and the first plunger member of the drive assembly shown in Fig. 17, in accordance with one aspect of the present invention, showing the plunger drive member disengaged from the first plunger member.

[0037] Fig. 25 is a perspective view of the plunger drive member and the first plunger member of the drive assembly shown in Fig. 17, in accordance with one aspect of the present invention, showing the plunger drive member disengaged from and axially offset relative to the first plunger member.

[0038] Fig. 26 is a front view of the first plunger member and the second plunger member of the drive assembly shown in Fig. 17, in accordance with one aspect of the present invention.

[0039] Fig. 27 is a top view of a drive unit for a drug delivery system in accordance with a further aspect of the present invention.

[0040] Fig. 28 is a perspective view of the drive assembly shown in Fig. 27, in accordance with one aspect of the present invention.

[0041] Fig. 29 is a sectional view of the drive assembly shown in Fig. 27 in accordance with one aspect of the present invention, showing a position prior to use of the drive assembly.

[0042] Fig. 30 is a perspective view of the drive assembly shown in Fig. 27, in accordance with one aspect of the present invention, showing the drive assembly received in a lower portion of the housing.

[0043] Fig. 31 is a perspective view of the housing shown in Fig. 30, in accordance with one aspect of the present invention.

[0044] Fig. 32 is a top view of the drive assembly shown in Fig. 27, in accordance with one aspect of the present invention, showing the engagement of the drive assembly with the needle drive portion in a pre-actuation position of the drive assembly.

[0045] Fig. 33 is an enlarged perspective view of the drive assembly shown in Fig. 27, in accordance with one aspect of the present invention, showing the engagement of the drive assembly with the needle drive portion in a pre-actuation position of the drive assembly.

[0046] Fig. 34 is a front view of a needle drive assembly in accordance with one aspect of the present invention.

[0047] Fig. 35 is a left perspective view of the needle shuttle of the needle drive assembly shown in Fig. 34, in accordance with one aspect of the present invention.

[0048] Fig. 36 is a right perspective view of the needle shuttle of the needle drive assembly shown in Fig. 34, in accordance with one aspect of the present invention.

[0049] Fig. 37A is a front view of the needle drive assembly shown in Fig. 34, in accordance with one aspect of the present invention, showing the needle drive assembly in a position prior to use.

[0050] Fig. 37B is a front view of the needle drive assembly shown in Fig. 34, in accordance with one aspect of the present invention, showing the needle drive assembly in a position of use.

[0051] Fig. 37C is a front view of the needle drive assembly shown in Fig. 34, in accordance with one aspect of the present invention, showing the needle drive assembly in an initial position after use.

[0052] Fig. 37D is a front view of the needle drive assembly shown in Fig. 34, in accordance with one aspect of the present invention, showing the needle drive assembly in a position after use.

[0053] Fig. 38A is a perspective view of the needle drive assembly shown in Fig. 34, in accordance with one aspect of the present invention, showing the needle drive assembly in a position of use.

[0054] Fig. 38B is a perspective view of the needle drive assembly shown in Fig. 34, in accordance with one aspect of the present invention, showing the needle drive assembly in an initial position after use.

[0055] Fig. 39 is a perspective view of the actuator button and needle drive assembly shown in Fig. 34, in accordance with one aspect of the present invention, showing the needle drive assembly in its initial position after use.

[0056] Fig. 40A is a cross-sectional view of the actuator button and needle drive assembly shown in Fig. 34, in accordance with one aspect of the present invention, showing the needle drive assembly in its initial position after use.

[0057] Fig. 40B is a perspective view of the actuator button and needle drive assembly shown in Fig. 34, in accordance with one aspect of the present invention, showing the needle drive assembly in a position after use.

[0058] Fig. 41 is a perspective view of a drive assembly for a drug delivery system in accordance with a further aspect of the present invention.

[0059] Fig. 42 is a perspective view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, with the upper housing portion removed.

[0060] Fig. 43 is a sectional view of the drive assembly shown in Fig. 41 in accordance with one aspect of the present invention.

[0061] Fig. 44 is a perspective view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention.

[0062] Fig. 45 is a sectional view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in a position prior to use.

[0063] Fig. 46 is a sectional view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in a position prior to use.

[0064] Fig. 47 is a top view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in a position prior to use.

[0065] Fig. 48 is a top view of the actuator assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the actuator assembly in a pre-actuated position.

[0066] Fig. 49 is a top view of the actuator assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the actuator assembly in a pre-actuated position.

[0067] Fig. 50 is a top view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in a pre-actuated position.

[0068] Fig. 51 is a top view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in a position of use.

[0069] Fig. 52 is a top view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in a position of use.

[0070] Fig. 53 is a sectional view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in a position of use.

[0071] Fig. 54 is a top view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in a position of use.

[0072] Fig. 55 is a sectional view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in a position of use.

[0073] Fig. 56 is a sectional view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in a position of use.

[0074] Fig. 57 is a top view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in a position of use.

[0075] Fig. 58 is a top view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in its initial position after use.

[0076] Fig. 59 is a perspective view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in its initial position after use.

[0077] Fig. 60 is a top view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in a position after use.

[0078] Fig. 61 is a top view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in a position after use.

[0079] Fig. 62 is a sectional view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in a position prior to use.

[0080] Fig. 63 is a sectional view of the drive assembly shown in Fig. 41, in accordance with one aspect of the present invention, showing the drive assembly in a position of use.

[0081] Fig. 64 is a perspective view of a drive assembly in accordance with a further aspect of the present invention.

[0082] Fig. 65A is a front view of a needle drive assembly in accordance with one aspect of the present invention, showing the needle drive assembly in a position of use.

[0083] Fig. 65B is a front view of the needle drive assembly shown in Fig. 65A, in accordance with one aspect of the present invention, showing the needle drive assembly in a position of use.

[0084] Fig. 65C is a front view of the needle drive assembly shown in Fig. 65A, in accordance with one aspect of the present invention, showing the needle drive assembly in an initial position after use.

[0085] Fig. 65D is a front view of the needle drive assembly shown in Fig. 65A, in accordance with one aspect of the present invention, showing the needle drive assembly in a position after use.

[0086] Fig. 65E is a front view of the needle drive assembly shown in Fig. 65A, in accordance with one aspect of the present invention, showing the needle drive assembly in a position prior to use.

[0087] Fig. 65F is a cross-sectional view of the needle drive assembly shown in Fig. 65A, in accordance with one aspect of the present invention, illustrating the needle drive assembly in a position prior to use.

[0088] Fig. 65G is a front view of the needle drive assembly shown in Fig. 65A, in accordance with one aspect of the present invention, showing the needle drive assembly in a pre-use position with the actuator button axially offset.

[0089] Fig. 65H is a cross-sectional view of the needle drive assembly shown in Fig. 65A, in accordance with one aspect of the present invention, showing the needle drive assembly in a pre-use position with the actuator button axially offset.

[0090] Fig. 66 is a perspective view of the spring of the button of the needle drive assembly shown in Fig. 65A, in accordance with one aspect of the present invention.

[0091] Fig. 67 is a perspective view of the actuator button of the needle drive assembly shown in Fig. 65A, in accordance with one aspect of the present invention.

[0092] Fig. 68 is a sectional view of the button spring and the actuator button of the needle drive assembly shown in Fig. 65A, in accordance with one aspect of the present invention.

[0093] Fig. 68A is a perspective view of the actuator button of the needle drive assembly shown in Fig. 65A, in accordance with a further aspect of the present invention.

[0094] Fig. 68B is a bottom view of the actuator button of the needle drive assembly shown in Fig. 65A, in accordance with a further aspect of the present invention.

[0095] Fig. 68C is a front view of the actuator button of the needle drive assembly shown in Fig. 65A, in accordance with a further aspect of the present invention.

[0096] Fig. 68D is a top view of the actuator button of the needle drive assembly shown in Fig. 65A, in accordance with a further aspect of the present invention, showing the actuator button in a position prior to use.

[0097] Fig. 68E is a front view of the actuator button of the needle drive assembly shown in Fig. 65A, in accordance with a further aspect of the present invention, showing the actuator button in a position prior to use.

[0098] Fig. 68F is a top view of the actuator button of the needle drive assembly shown in Fig. 65A, in accordance with a further aspect of the present invention, showing the actuator button in a position of use.

[0099] Fig. 68G is a front view of the actuator button of the needle drive assembly shown in Fig. 65A, in accordance with a further aspect of the present invention, showing the actuator button in a position of use.

[00100] Fig. 69 is a top view of the actuator button of the needle drive assembly shown in Fig. 65A, in accordance with one aspect of the present invention.

[00101] Fig. 70A is a schematic illustration of a drive assembly in accordance with one aspect of the present invention, showing the drive assembly in a position prior to use.

[00102] Fig. 70B is a schematic illustration of the drive assembly shown in Fig. 70A, in accordance with one aspect of the present invention, showing the drive assembly in a position of use.

[00103] Fig. 70C is a schematic illustration of the drive assembly shown in Fig. 70A, in accordance with one aspect of the present invention, showing the drive assembly in a position of use.

[00104] Fig. 70D is a schematic illustration of the drive assembly shown in Fig. 70A, in accordance with one aspect of the present invention, showing the drive assembly in a position of use.

[00105] Fig. 70E is a schematic illustration of the drive assembly shown in Fig. 70A, in accordance with one aspect of the present invention, showing the drive assembly in a position of use.

[00106] Fig. 70F is a schematic illustration of the drive assembly shown in Fig. 70A, in accordance with one aspect of the present invention, showing the drive assembly in a position after use.

[00107] Fig. 70G is a schematic illustration of the drive assembly shown in Fig. 70A, in accordance with one aspect of the present invention, showing the drive assembly in a position after use.

[00108] Fig. 71 is a perspective view of a spacer assembly for a drug delivery system in accordance with one aspect of the present invention, showing an assembled position prior to use of the spacer assembly.

[00109] Fig. 72 is a perspective view of the spacer assembly shown in Fig. 71, in accordance with one aspect of the present invention, showing a position in which the spacer assembly is used.

[00110] Fig. 73 is a perspective view of the spacer assembly shown in Fig. 71, in accordance with one aspect of the present invention, showing the initial position after use of the spacer assembly.

[00111] Fig. 74 is a perspective view of a limiting element in accordance with one aspect of the present invention.

[00112] Fig. 75 is a front view of a spacer assembly for a drug delivery system in accordance with a further aspect of the present invention.

[00113] Fig. 76 is a top view of a spacer assembly for a drug delivery system in accordance with one aspect of the present invention.

[00114] Fig. 77 is a perspective view of the spacer assembly shown in Fig. 76, in accordance with one aspect of the present invention.

[00115] Fig. 78 is a sectional view of the spacer assembly shown in Fig. 76, in accordance with one aspect of the present invention.

[00116] Fig. 79 is a perspective view of a spacer assembly for a drug delivery system in accordance with a further aspect of the present invention.

[00117] Fig. 80 is a perspective view of a spacer assembly for a drug delivery system in accordance with another aspect of the present invention.

[00118] Fig. 81A is a sectional view of the strut assembly shown in Fig. 80, in accordance with one aspect of the present invention, showing a position prior to assembly of the strut assembly.

[00119] Fig. 81B is a sectional view of the strut assembly shown in Fig. 80, in accordance with one aspect of the present invention, showing an assembled position of the strut assembly.

[00120] Fig. 82 is a perspective view of a drive assembly for a drug delivery system in accordance with one aspect of the present invention.

[00121] Fig. 83 is a perspective view of the drive assembly shown in Fig. 82, in accordance with one aspect of the present invention, with the upper housing portion removed.

[00122] Fig. 84 is a sectional view of the drive assembly shown in Fig. 82, in accordance with one aspect of the present invention, showing a position prior to use of the drive assembly.

[00123] Fig. 85 is an enlarged cross-sectional view of the drive assembly shown in Fig. 82, in accordance with one aspect of the present invention, showing a position prior to use of the drive assembly.

[00124] Fig. 86 is a top view of the biasing member of the drive assembly shown in Fig. 82, in accordance with one aspect of the present invention.

[00125] Fig. 87 is a perspective view of the drive assembly shown in Fig. 82, in accordance with one aspect of the present invention, showing the limiting member engaged with the drive assembly.

[00126] Fig. 88 is a perspective view of a drive assembly for a drug delivery system in accordance with one aspect of the present invention.

[00127] Fig. 89 is a perspective view of the drive assembly shown in Fig. 88 in accordance with one aspect of the present invention, showing a position prior to use of the drive assembly.

[00128] Fig. 90 is a sectional view of the drive assembly shown in Fig. 88, in accordance with one aspect of the present invention.

[00129] Fig. 91 is a perspective view of the drive assembly shown in Fig. 88, in accordance with one aspect of the present invention, showing a position after use of the drive assembly.

[00130] Fig. 92 is a sectional view of the drive assembly shown in Fig. 88, in accordance with one aspect of the present invention, showing a position prior to use of the drive assembly.

[00131] Fig. 93 is a front view of the drive assembly shown in Fig. 88, in accordance with one aspect of the present invention, showing a position in which the drive assembly is in use.

[00132] Fig. 94 is a perspective view of a spacer assembly for a drug delivery system in accordance with one aspect of the present invention.

[00133] Fig. 95 is a front view of the spacer assembly shown in Fig. 94, in accordance with one aspect of the present invention.

[00134] Fig. 96 is a sectional view of the spacer assembly shown in Fig. 94, in accordance with one aspect of the present invention.

[00135] Fig. 97 is a perspective view of the spacer assembly shown in Fig. 94, in accordance with one aspect of the present invention, with the washer removed.

[00136] Fig. 98 is a perspective view of a fixed strut of the strut assembly shown in Fig. 94, in accordance with one aspect of the present invention.

[00137] Fig. 99 is a perspective view of an adjustable strut of the strut assembly shown in Fig. 94, in accordance with one aspect of the present invention.

[00138] Fig. 100 is a perspective view of the spacer assembly washer shown in Fig. 94, in accordance with one aspect of the present invention.

[00139] Corresponding reference numerals indicate corresponding parts throughout the several views. The illustrative examples provided in this application illustrate exemplary aspects of the invention, and these illustrative examples should not be construed in the sense of limiting the scope of the invention in any way.

DETAILED DESCRIPTION

[00140] The following description is intended to enable those skilled in the art to make and use the described embodiments for carrying out the invention. However, various modifications, equivalents, variations, and alternatives will be readily apparent to those skilled in the art. All such modifications, variations, equivalents, and alternatives are intended to be within the spirit and scope of the present invention.

[00141] For purposes of the following description, the terms "upper", "lower", "right", "left", "vertical", "horizontal", "top", "bottom", "lateral", "longitudinal" and their derivatives shall refer to the invention as oriented in the drawings. However, it should be understood that the invention may admit of various alternative embodiments, except where otherwise expressly provided. It should also be understood that the specific devices shown in the accompanying drawings and characterized in the following description are merely exemplary embodiments of the invention. Accordingly, specific dimensions and other physical characteristics related to the embodiments disclosed in this description should not be considered limiting.

[00142] As shown in Fig. 1-16, a drug delivery system 10 according to one aspect of the present invention includes a drive unit 12, a container 14, a valve assembly 16, and a needle drive unit 18. The drive unit 12, the container 14, the valve assembly 16, and the needle drive unit 18 are at least partially located within a housing 20. The housing 20 includes an upper portion 22 and a lower portion 24, although other designs can be used for the housing 20. In one aspect, the drug delivery system 10 is an injector device configured to be worn or attached to a user and to deliver a predetermined dose of a drug prepared within the container 14 by injection into the user. The system 10 can be used to deliver a "bolus injection" in which the drug is delivered within a set period of time. The drug can be delivered over a period of time up to 45 minutes, although other suitable injection volumes and durations can be used. Bolus administration or bolus delivery can be performed with or without a specific rate adjustment. The system 10 can deliver the drug to the user under constant pressure, at a variable rate. The general operation of the system 10 is described below with reference to Figs. 1-16, with specific details about the drive unit 12, the needle drive unit 18 and other design features of the system 10 being set forth below in connection with Figs. 17-93.

[00143] As also shown in Fig. 1-16, the system 10 is configured to operate upon actuation of the actuator button 26 by the user, which causes the needle 28 of the needle assembly 18 to pierce the skin of the user, actuate the drive assembly 12 to position the needle 28 in fluid communication with the container 14 and to expel the fluid or drug from the container 14, and retract the needle 28 after the injection of the drug is completed. The general operation of the drug delivery system is presented and described in International Publication Nos. 2013/155153 and 2014/179774, which are incorporated herein by reference in their entirety. The housing 20 of the system 10 includes an indicator window 30 for observing an indicator device 32, configured to present to the user an indication of the state of the system 10, and a container window 31 for observing the container 14. The indicator window 30 can be a magnifying glass to ensure good visibility of the indicator device 32. The indicator device 32 moves together with the drive unit 18 of the needle during use of the system 10 to show the state before use, the state of use and the state after use of the system 10. The indicator device 32 presents visual signs related to the state, although it is possible to provide other suitable signs, such as sound or tactile, as alternative or additional signs.

[00144] As shown in Fig. 4-6, in the position before using the system 10, the container 14 is spaced from the drive unit 12 and the valve unit 16, and the needle 28 is in a retracted position. During a preliminary actuation of the system 10, as shown in Fig. 7-9, the drive unit 12 engages the container 14 to move the container 14 toward the valve unit 16, which is configured to pierce the cap 36 of the container 14 and place the drug inside the container 14 in a state of fluid communication with the needle 28 through a tube (not shown) or through another suitable device. The drive unit 12 is configured to engage with the stopper 34 of the container 14, which will initially move the entire container 14 into engagement with the valve unit 16 due to the incompressibility of the fluid or drug within the container 14. The pre-action of the system 10 is caused by actuating the actuator button 26 by the user, which releases the drive unit 18 of the needle and the drive unit 12, as described in detail below. During the pre-action, the needle 28 is still in the retracted position and is ready to move to the extended position for injection into the user of the system 10.

[00145] In the use position of the system 10, as shown in Figs. 10-12, the needle 28 is in an extended position at least partially outside the housing 20, and the drive unit 12 moves the stopper 34 inside the container 14 to deliver the drug from the container 14 through the needle 28 and into the user. In the use position, the valve assembly 16 has already pierced the cap 36 of the container 14 to place the container 14 in a state of fluid communication with the needle 28, which also allows the drive unit 12 to move the stopper 34 relative to the container 14, since the fluid is able to be dispensed from the container 14. In the post-use position of the system 10, shown in Fig. 13-15, the needle 28 is in a retracted position and engaged with the liner 38 to seal the needle 28 and prevent any residual leakage of fluid or drug from the container 14. The container 14 and the valve assembly 16 may be the container 14 and the valve assembly 16 shown and described in International Publication No. WO 2015/081337, which is incorporated herein by reference in its entirety.

[00146] As shown in Fig. 15A-15C, the backing 38 is displaced into the needle when the needle drive unit 96 is moved from the use position to the post-use position. In particular, the lining 38 is placed on a lining bracket 122 having a cam surface 124 which interacts with a working surface 126 of the cam on the lower section 24 of the housing 20. The lining bracket 122 is connected to the needle drive unit 96 by means of a torsion rod 128. The cam surface 124 is configured to engage with the working surface 126 of the cam in order to deflect the lining bracket 122 downwards and, thereby, ensure that the lining 38 passes under the needle 28 before moving upwards into the needle 28. The torsion rod 128 allows the lining bracket 122 to twist around the support point of the needle drive unit 96. The lining 38 can be pressed into the opening of the lining bracket 122, although other suitable designs for securing the lining 38 can be used.

[00147] Fig. 1-33 shows an actuator assembly 12 according to one aspect of the present invention. As described above, the actuator assembly 12 is configured to move the container 14 to pierce the lid 36 of the container 14, and to move the stopper 34 inside the container 14 to dispense a fluid or a drug from the container 14. The actuator assembly 12 shown in Fig. 17-33 is configured to engage and cooperate with a spacer assembly 40 received in the stopper 34 of the container 14. The spacer assembly 40 includes a spacer 42 and a spacer holder 44. The spacer holder 44 is received in the stopper 34, and the spacer 42 is received in the spacer holder 44. The spacer holder 44 includes a first threaded portion 46 that engages with a corresponding threaded portion of the plug 34, although other suitable designs can be used. The spacer 42 also includes a threaded portion 48 that engages with a corresponding second threaded portion 50 of the spacer holder 44 for securing the spacer 42 to the spacer holder 44, although other suitable designs can be used. The drive unit 12 is configured to dispense a variety of predetermined filling volumes of the container 14, while maintaining the functional features of the above-described system 10, including, but not limited to, retracting the needle 28 after the end of the dose administration and providing an indication of the state of the system 10, as well as minimizing the abrupt engagement of the plug 34 by the drive unit 12. The drive unit 12 is configured to dispense a plurality of ranges of discrete filling volumes by using a plurality of sizes of the spacer 42. In one aspect, twelve ranges of filling volumes and twelve sizes of the spacer 42 are provided. In one aspect, the length of the spacer 42 is varied to provide different filling volumes in the container 14. Alternatively, it is possible to use the spacer 42 of one size with a plurality of filling volumes in the container 14, provided by using a plurality of washers that fit in the spacer 42.

[00148] As shown in Fig. 17-26, the drive unit 12 includes a first plunger member 52, a second plunger member 54 received in the first plunger member 52, a first biasing member 56, a second biasing member 58, a plunger drive member 60 and a indexing member 62. The first plunger member 52 is movable from a position before use (shown in Fig. 18), to a position in use (shown in Fig. 19), to a position after use (shown in Fig. 20), and the first plunger member 52 is configured to engage with the spacer assembly 40 and move the stopper 34 inside the container 14 to dispense the medicament from the container 14. The first plunger member 52 is configured to be axially movable. The second plunger element 54 and the first plunger element 52 form a telescopic structure, wherein the second plunger element 54 is designed with the possibility of axial movement after the first plunger element 52 has moved a predetermined axial distance. The movement of the first and second plunger elements 52, 54 is ensured by the first and second biasing elements 56, 58, which are compression springs, although other suitable structures can be used for the biasing elements 56, 58.

[00149] The first biasing element 56 is received in the second plunger element 54 and is enclosed between the plunger drive element 60 (and the step-and-rotate element 62) and the first seat 64 of the spring of the second plunger element 54. The second biasing element 58 is located radially inside relative to the first biasing element 56 and is received in the second plunger element 54. The second biasing element 58 is enclosed between the second seat 66 of the spring of the second plunger element 54 and the first plunger element 52. The second biasing element 58 is configured to bias the first plunger element 52 toward the container 14 from the position before use to the position of use and to the position after use. The first biasing element 56 is configured to bias the second plunger element 54 toward the container 14, which in turn biases the first plunger element 52 toward the container 14 from the position before use to the position of use and to the position after use. In particular, the second biasing member 58 is configured to drive the first plunger member 52 against the resistance of the spacer assembly 40 or the stopper 34 to move the container 14 into engagement with the valve assembly 16, thereby piercing the lid 36 of the container 14 and placing the container 14 in a state of fluid communication with the needle 28. The first biasing member 56 is configured to move the stopper 34 within the container 14 to dispense the drug from the container 14. The second biasing member 58 has a different spring constant than the first biasing member 56. In particular, the second biasing member 58 is stiffer than the first biasing member 56 to provide a significant force for piercing the lid 36 of the container 14, whereas the first biasing member 56 develops a smaller force for dispensing, suitable for the viscosity of the fluid or medicinal product inside container 14.

[00150] As also shown in Fig. 17-26, the plunger drive element 60 has an annular section 68 and a spindle section 70. The plunger drive element 60 is rotationally movable relative to the first plunger element 52 between a first angular position and a second angular position spaced from the first angular position. The first angular position may be spaced 15 degrees from the second angular position, although other suitable positions may be used. The annular section 68 includes a leading surface 72 that includes a plurality of teeth 74, although other suitable designs may be used for the leading surface 72. The spindle section 70 includes a drive fixation surface 76 intended for engagement and disengagement with a plunger fixation surface 78 of the first plunger element 52. The plunger fixation surface 78 includes a plurality of projections 80 configured to be received in a plurality of grooves or slots 81 formed by the drive fixation surface 76.

[00151] As shown in Fig. 18 and 23, in the first angular position of the plunger drive member 60, the plurality of projections 80 and the plurality of grooves or slots 81 are misaligned such that the plunger drive member 80 engages with the first plunger member 52 to prevent the first and second plunger members 52, 54 from moving under the action of the first and second biasing members 56, 58, pressing the first and second plunger members 52, 54 away from the plunger drive member 60. As shown in Fig. 19 and 24, in the second angular position of the plunger drive element 60, the plurality of projections 80 and the plurality of grooves or slots 81 are aligned with each other so that the plunger drive element 60 disengages from the first plunger element 52 to allow movement of the first and second plunger elements 52, 54 and thereby begin the dosing process from the container 14.

[00152] As shown in Fig. 7 and 33, the leading surface 72 of the plunger driving member 60 is configured to engage with a portion of the needle driving unit 18. After the actuator button 26 is actuated and the needle driving unit 18 is released, which will be described in detail below, the needle driving unit 18 moves inside the housing 20 from the position before use to the position of use and to the position after use. During the initial movement of the needle driving unit 18, a portion of the needle driving unit 18 engages with the leading surface 72 of the plunger driving member 60 to move the plunger driving member 60 from the first angular position to the second angular position. As shown in Fig. 33, the inclined plate-shaped portion 82 of the needle driving unit 18 engages the leading surface 72 of the plunger driving member 60 to cause the plunger driving member 60 to rotate.

[00153] As shown in Fig. 11, 13 and 26, the second plunger member 52 includes a plurality of coded projections 84, wherein a preselected one of the plurality of coded projections 84 is configured to engage a limiting member 86 of the system 10. As described in detail below, the limiting member 86 cooperates with the needle drive assembly 18 and limits the movement of the needle drive assembly 18 from the use position to the post-use position until the stopper 34 reaches a predetermined end-of-dose position. In one aspect, the limiting member 86 is configured to limit axial movement of the needle drive assembly 18 from the use position by means of engagement between the limiting member 86 and a portion of the needle drive assembly 18. Such engagement between the limiting member 86 and the needle drive assembly 18 is disengaged by rotation of the limiting member 86 when the stopper 34 reaches the end-of-dose position. In the position of use of the needle drive unit 18, the limiting element 86 is biased in the direction of rotation, wherein the rotation of the limiting element 86 is blocked by the engagement between the limiting element 86 and one of the plurality of coded projections 84 of the second plunger element 54. The plurality of coded projections 84 may be axial ribs of different lengths, although other suitable designs may be used. Each coded projection 84 defines a point at which the limiting element 86 is able to rotate, thereby releasing the needle drive unit 18. The smooth section of the second plunger element 52 may also provide an additional "code" for determining when the system 10 moves to the position of the end of dose administration.

[00154] As described above, the indicator device 32 moves, thereby providing visibility of different portions of the indicator device 32 through the indicator window 30, as the system 10 moves from the pre-use position to the use and post-use or end-of-dose positions. In particular, the indicator device 32 engages a portion of the limiting member 86 and moves with the limiting member 86 through different stages of the system 10 to provide the user with an indication of the state of the system 10.

[00155] During assembly of the system 10, the dose in the container 14 is matched with a specific spacer 42 having a set length, and a corresponding one of the plurality of coded projections 84 is matched with the limiting element 86. Accordingly, as described above, the container 14 can be provided with a plurality of dosage volumes, wherein each volume corresponds to a specific spacer 42 and a coded projection 84. Thus, even with different dosage volumes, the system 10 is configured to insert the needle 28 into the user to deliver a dose of the drug from the container 14, retract the needle 28 after the end of the dose administration and provide an indication of the state of the system 10, while minimizing the abrupt engagement of the plug 34 by the drive assembly 12. In particular, the size of the plug 34 can be selected to minimize the distance between the first plunger element 52 and the spacer unit 40 and not require the use of damping.

[00156] Fig. 27-33 shows an actuator assembly 12A according to a further aspect of the present invention. The actuator assembly 12A shown in Fig. 27-33 is similar to the above-described actuator assembly 12 shown in Fig. 17-26 and operates in the same way. However, in the actuator assembly shown in Fig. 27-33, the first plunger member 52 is received in the second plunger member 54 and extends from the second plunger member 54 during the axial movement from the position before use to the position of use. In addition, the first plunger element 52 includes a retractable portion 88 configured to engage with the second plunger element 54 after the first plunger element 52 has moved a predetermined axial distance so that the first and second plunger elements 52, 54 move together. The first and second biasing elements 56, 58 contact the first and second plunger elements 52, 54 and act on them in the same way as in the drive unit 12 shown in Fig. 17-26.

[00157] As shown in Fig. 27-32, the indexing member 62 is located around the first and second plunger members 52, 54 and includes a plurality of ratchet teeth 90 configured to engage with a flexible plate 92 located on the lower portion 24 of the housing 20. When the drive assembly 12, 12A is installed in the lower portion 24 of the housing 20, the engagement of the ratchet teeth 90 of the indexing member 62 with the flexible plate 92 of the housing 20 provides a unidirectional rotation of the indexing member 62. The indexing member 62 is configured to rotate to match one of the coded projections 84 of the second plunger member 52 with the limiting member 86, based on the dosage volume and the size of the spacer 42, as described above. The step-rotary element 62 can provide 24 angular positions of the drive unit 12, 12A, of which 12 positions can have specific dose values that correspond to them.

[00158] Figs. 1-16 and 34-40B show a needle drive assembly 18 in accordance with one aspect of the present invention. The needle drive assembly 18 includes a needle drive block 96 having guide surfaces 98, a needle shuttle 102 having cam surfaces 104, and a needle 28 received in the needle shuttle 102 and configured to communicate via a fluid medium with the container 14, as described above. The needle drive block 96 is, in general, rectangular, with guide surfaces 98 extending radially inward. The needle shuttle 102 is received inside the needle drive block 96. As described above, the needle drive unit 96 is movable within the housing 20 from a pre-use position (shown in Figs. 4-6) to a pre-actuation position (Figs. 7-9), a use position (Figs. 10-12) and a post-actuation position (Figs. 13-15). The needle drive unit 96 is biased from the pre-use position to the post-use position by means of an extension spring 106, although other suitable biasing structures can be used. The needle drive unit 96 is released and can move freely from the pre-use position to the use position upon actuation of the actuator button 26, which is described in detail below. The needle drive unit 96 moves from the use position to the post-use position upon rotation of the limiting member 86, as described above in connection with Figs. 17-33.

[00159] As shown in Fig. 34-40B, the needle shuttle 102 is movable along a vertical axis between a retracted position in which the needle 28 is located inside the housing 20 and an extended position in which at least a portion of the needle 28 extends from the housing 20. The needle shuttle 102 is movable between the retracted position and the extended position due to the engagement between the guide surfaces 98 of the needle drive unit 96 and the cam surfaces 104 of the needle shuttle 102. The cam surfaces 104 are provided by means of the first and second cam elements 108, 110, wherein the first cam element 108 is spaced apart from the second cam element 110. The housing 20 includes a guide post 112 containing a recess configured to receive a T-shaped projection 114 on the needle shuttle 102, although other shapes and configurations can be used for the guide post 112 and the T-shaped projection 114. The needle shuttle 102 moves along the guide post 112 between the retracted and extended positions. The guide post 112 is rectilinear and extends approximately perpendicularly from the housing 20, although other suitable designs can be used. The guide surfaces 98 of the needle drive unit 96 are non-rectilinear and each comprise a first side 116 and a second side 118 located opposite the first side 116.

[00160] As described below, the guide surfaces 98 of the needle driving unit 96 cooperate with the cam members 108, 110 of the needle shuttle 102 to move the needle shuttle 102 vertically between the retracted and extended positions when the needle driving unit 96 moves axially from the position before use to the position after use. The needle shuttle 102 also includes a shuttle biasing member 120 configured to engage the housing 20 or the actuator button 26. In particular, the shuttle biasing member 120 is engaged with the housing 20 or the actuator button 26 and provides a biasing force when the needle driving unit 96 moves from the use position to the post-use position. When the needle driving unit 96 completely moves to the position after use, the cam members 108, 110 of the needle shuttle 102 disengage from the guide surfaces 98 of the needle driving unit 96, and the shuttle biasing member 120 biases the needle shuttle 102 downward so that the needle 28 comes into contact with the backing 38, as described above. However, as described above in connection with Fig. 1-16, the backing 38 can also bias into the needle 28 instead of biasing the needle shuttle 102 downward by the shuttle biasing member 120. The needle driving unit 96 can cooperate with the actuator button 26 to prevent the actuator button 26 from being pushed back until the position after use is reached, which will be described in detail below.

[00161] As shown in Fig. 37A-40B, in the position before use (Fig. 37A), the needle shuttle 102 is in a retracted position, and the cam members 108, 110 are spaced from the guide surface 98 of the needle driving unit 96. When the needle driving unit 96 is moved to the use position (Fig. 37B and 38A), the second cam member 110 of the needle shuttle 102 engages with the second side 118 of the guide surfaces 98 to move the needle shuttle 102 from the retracted position to the extended position. During the transition from the use position to the post-use position of the needle drive unit 96 (Fig. 37C), the first cam member 108 of the needle shuttle 102 engages with the first side 116 of the guide surfaces 98 to move the needle shuttle 102 from the second position to the first position. After the needle drive unit 96 is completely transitioned to the post-use position (Figs. 37D and 38B), the shuttle biasing member 120 biases the needle shuttle 102 downward when the cam members 108, 110 disengage from the guide surfaces 98 of the needle drive unit 96, wherein the needle 28 engages with the backing 38. The transition of the needle drive unit 96 and the corresponding position of the needle shuttle 102 are also shown in Figs. 39-40B. The interaction between the actuator button 26 and the needle drive unit 96 is described in detail in connection with Figs. 65A-67. Figs. 41-64 show a drug delivery system 200 according to a further embodiment. The system 200 includes a housing 202 that includes an upper housing 204 and a lower housing 206. The housing has a proximal end 205 and a distal end 207. The upper housing 204 contains a status observation port 208 so that the user can observe the operating state of the system 200. The system 200 also includes a valve assembly 212, a tube 214 fluidly connecting the valve assembly 214 with a patient needle 215, which is located on the proximal end of the needle bracket 216. A spring 218 biases the needle driver 220 in the distal direction.

[00162] As shown in Figs. 42-46, the system 200 further includes a container or container 222 with a drug with a stopper 224 movably positioned in this container, although the stopper 224 is not shown in the various figures for clarity. In a preferred embodiment, the distal end of the container 222 with a drug comprises a membrane assembly 228, which is spaced from the valve assembly 212 before the device 222 is activated, as best shown in Fig. 47.

[00163] For manufacturing purposes, it is often desirable to use a single size for a container with a drug, even if several container fill volumes or dosages are intended to be used. In such cases, when filling containers with drugs, different fill volumes are obtained at different positions of the stopper. In order to provide for such different positions of the stopper, as well as to provide for differences in the manufacture of stoppers, aspects of the present invention include individual or customized spacers 226 located in the proximal end of the container 222, proximal to the stopper 224. In other words, the individual spacer 226 provides an option that allows for dispensing a variety of predetermined fill volumes established during manufacture by selecting different spacers 226 and reduces or eliminates the need for reconfiguration operations of the assembly. The size of the spacer 226 can be used to account for underfilled volumes of the container 222 and to provide a suitable supporting surface at the proximal end of the container.

[00164] The spacer 226 is selected from a plurality of spacers 226 of different sizes to occupy the space from the proximal end of the plug 224 to the proximal end of the container 222. According to one embodiment, as shown in Figs. 45-47, the spacer 226 is selected so that it is substantially flush with the proximal end of the container 222. Furthermore, according to one embodiment, the spacer 226 has the shape of a “cylinder” that includes a central post 230 and a distal flange 232, as best shown in Fig. 45.

[00165] As shown in Fig. 44-47, the system 200 also includes a drive assembly 234 for distally displacing the container 222 to create a fluid connection between the container 222 and the needle 215 for the patient, as well as to dispense a drug from the container 222. In more detail, the drive assembly 234 includes an internal spring 236 located inside the central plunger 238, an outer plunger 240, an external spring 242 located between the central plunger 238 and the outer plunger 240, a telescopic member 244 and a release valve 246.

[00166] In a preferred embodiment, the inner spring 236 has a higher spring constant than the outer spring 242 and is therefore stronger or stiffer than the outer spring 242. The inner spring 236 is located within the central plunger 238 and operates to compress between the spring flange 248 in the lower housing (best shown in Fig. 46) and the central plunger 238, which presses directly on the proximal end of the spacer 226 after the device is actuated. The outer spring 242 is located inside the outer plunger 240 and operates to compress between the proximal outer flange 250 of the central plunger 238 and the distal inner flange 252 of the outer plunger 240. Thus, the inner and outer springs 236 and 242 are nested one inside the other and can provide a more compact drive unit (and, therefore, a more compact system 200) than when using a single spring.

[00167] According to one aspect, the inner spring 236 performs only the function of biasing the container 222 to create a fluid connection with the needle 215 for the patient, and the outer spring 242 performs only the function of subsequently dosing the drug from the container 222. According to another aspect, the inner spring 236 performs the function of biasing the container 222 to create a fluid connection with the needle 215 for the patient, and also performs the function of starting the dosing of the drug from the container 222, and the outer spring 242 performs the function of completing the dosing of the drug. According to a further aspect, the inner spring 236 forces the initial piercing of the container 222, wherein the outer spring 242 completes the piercing and dosing of the drug from the container 222.

[00168] As shown in Figs. 44-47 and described in detail below, the outer plunger 240 includes a pair of proximal flanges or legs 254 that each have a beveled surface that interacts with a corresponding beveled surface (or surfaces) on the release valve to retain and then release the power module after the device 200 is actuated.

[00169] As best shown in Figs. 46 and 47, in the initially assembled state, the container 222 is positioned with a clearance from the drive assembly 234 and the valve assembly 212. The side flange 256 on the needle drive 220 axially holds the container 222 with the drug, and the needle drive 220 prevents lateral displacement of the release valve 246. According to one embodiment, a spring (not shown) biases the needle drive 220 in a distal direction, but the actuator button 210 (and/or an associated assembly) prevents distal displacement of the needle drive 220 before actuating the device 200. The status tape 258 is located on the needle drive 220 and has a top surface that is visible through the status observation port 208. According to one embodiment, the upper surface of the status tape has a plurality of colors or patterns, and when the device is in the pre-activation state, a first color or pattern, such as yellow, is visible through the status observation port 208.

[00170] Figs. 48-52 are top views of the system 200 illustrating the execution of actions during the stage of actuating the system 200 and thereafter. As shown in Fig. 47, the user moves the actuator button 210 in the proximal direction and then moves the button 210 vertically into the housing 202, thereby releasing the needle driver 220 for its distal displacement under the action of a spring (not shown for clarity). As shown in Fig. 49, when the needle driver is distally displaced, the guide grooves 260 on the needle driver 220 cooperate with the side projections 262 on the needle bracket 216 to insert the needle 215 for the patient. At this stage, the proximal end of the needle driver 220 has preferably not yet released the release valve 246, and therefore the drive assembly 234 is not yet unlocked. However, the side flange 256 has shifted distally and therefore the container 222 is not retained.

[00171] Then, as shown in Figs. 50 and 51, with continued distal displacement, the proximal end of the needle drive 220 releases the release valve 246 (thus releasing the drive assembly 234). The needle drive 220 is temporarily suspended when it abuts against the structural element on the rotary locking and releasing plate 264, with the locking and releasing plate 264 brought close to the remote stop 266 (best shown in Figs. 44 and 59) of the telescopic member 244. The needle drive 220 remains in this position until the drug is dispensed. In this position, the second color or pattern of the status tape 258, for example, green, is preferably visible through the status observation port 208.

[00172] At this stage, the force of the springs 236 and 242 and the interaction of the beveled surfaces of the proximal flanges or legs 254 with the corresponding beveled surface (or surfaces) on the release bolt 246 forces the release bolt 246 to move laterally, thereby releasing the outer plunger 240 from the retaining engagement with the release bolt 246. Up to this point, the outer plunger 240 held the central plunger 238.

[00173] As shown in Figs. 52 and 53 (the internal spring 236 is not shown in Fig. 52 for clarity), the stiff internal spring 236 moves the central plunger 238 in a distal direction until it contacts the spacer 226. Since the drug container 222 is filled with a substantially incompressible fluid, the continued distal displacement of the central plunger 238 distally displaces the spacer 226, the plug 224, and the container 222 relative to the housing 202. This distal displacement causes the septum assembly 228 to be pierced by the valve assembly 212, creating fluid communication between the container 222 and the patient needle 215. The central plunger 238 moves in a distal direction until its proximal outer flange 250 (best shown in Fig. 59) comes into contact with a flange on the lower housing 206, which limits the "piercing stroke." In a preferred embodiment, another flange on the lower housing 206 and/or a side flange 256 of the needle drive 220 limits the distal stroke of the container 222.

[00174] Thereafter, since the inner spring 236 can no longer distally bias the central plunger 238, the softer outer spring 242 distally biases the outer plunger 240 relative to the central plunger 238 until it contacts the distal flange 232 of the spacer 226, as shown in Figs. 54 and 55. As will be described in detail below, the contact between the outer plunger 240 and the spacer 226 is preferably damped to minimize the impact effect. Further expansion of the outer spring 242 distally biases the outer plunger 240 to dispense the medication.

[00175] As shown in Figs. 56 and 57, as the outer spring 242 continues to expand and distally bias the outer plunger 240, after a predetermined distal displacement of the outer plunger 240 relative to the telescopic member 244, the outer structural member or flange 268 of the outer plunger 240 interacts with the inner distal structural member or flange 270 of the telescopic member 244 and “grabs” the telescopic member 244. This “grabbing” ensures that further distal displacement of the outer plunger 240 causes a corresponding distal displacement of the telescopic member 244. This coupled distal displacement continues until the end of the dosage of the drug.

[00176] As noted above, the remote stop 266 is located on the telescopic member 244. The axial length of the remote stop and the travel of the telescopic member 144 in the distal direction regulates the synchronization of the disengagement of the remote stop 266 from the locking-release plate 264. As shown in Figs. 58 and 59, at the end of the dosage of the drug, the proximal end of the remote stop 266 bypasses the locking-release plate 264. This allows the locking-release plate 264 to rotate out of engagement with the needle drive 220 (Fig. 60) and allows the needle drive 220 to continue its distal displacement and retract the needle 215 for the patient (Fig. 61). At this stage, a different color or pattern of the status tape 258 is visible through the status monitoring port 208, for example, red, meaning that the device 200 has completed its operation.

[00177] As noted above and shown in Figs. 62 and 63, the contact between the outer plunger 240 and the spacer 226 is preferably damped to minimize impact. The maximum degree of energy dissipation is required for underfilled syringes containing a viscous fluid, since the outer spring 242 will be stiffer to provide the desired dispensing rates. The minimum degree of energy dissipation is required for fully filled syringes containing a low-viscosity fluid, since the outer spring may be less stiff to provide the desired dispensing rates. Various methods can be used to adjust the damping levels, such as pneumatic damping or closed-cell foam damping.

[00178] As another method of damping, Fig. 64 shows an embodiment of the spacer 226, on which one or more axial contact ribs 272 are arranged circumferentially around the central post 230 of the spacer 226. In this embodiment, the outer plunger 240 must move along the contact ribs 272, which creates a frictional resistance to the distal displacement of the outer plunger 240 relative to the spacer 226. The resistance force created by the interaction between the contact ribs 272 and the outer plunger 240 is independent of the speed of the plunger. The resistance force, preferably, does not exceed the minimum load of the metering spring to avoid jamming of weak springs. The interaction can be adjusted to provide a desired level of frictional resistance. For different fluid viscosities, contact ribs 272 of different (axial and/or radial) sizes can be used. This may mean using a custom or bespoke spacer for each viscosity and fill level combination, or, depending on the number of springs required for a viscosity range, there may be multiple adjustable positions whereby the spacer can be set to a specific position for a particular spring type (the position being characterized by the interaction/damping tuned for that particular spring load/viscosity combination).

[00179] Fig. 65A-69 show the structure 280 of the actuator button for actuating the system 10 in accordance with one aspect of the present invention. The structure 280 of the actuator button includes the actuator button 26, the button spring 284 and the needle drive unit 286. The needle drive unit 286 may be similar to the needle drive units 96, 220 described above and is configured to move within the housing 20 to move the needle shuttle 102 or the needle 28 between the retracted and extended positions. As shown in Fig. 69, the actuator button 26 includes a user interface portion 288 for interacting with the user. The user interface portion 288 preferably has a length of about 22 mm and a width of about 10 mm, although other suitable dimensions can be used. The actuator button 26 includes two pairs of locking tabs 290, 292, which interact with the contact surfaces 294, 296 with the button on the needle drive unit 286 before the device is activated, in order to prevent the needle drive unit 286 from swinging upward. As shown in Fig. 65H, the mutual overlapping of the needle drive unit 286 and the housing 20 prevents premature actuation. As shown in Fig. 66, the spring 284 of the button includes a first support surface 298 and a second support surface 300, spaced from the first support surface 298, and a cantilever central spring tab 302, surrounded by a pair of outer tabs 304, which are connected by the first support surface 298.

[00180] The structure 280 of the actuator button is configured to provide one or more of the following functions, which are described in detail below: a unidirectional axial displacement or shift of the actuator button 26; a lateral movement (to a raised and depressed position) of the actuator button 26, wherein the actuator button 26 remains depressed in the position of use of the needle drive unit 286; and a locking of the actuator button 26 in the position after use of the needle drive unit 286, so that the button 26 is in a raised position and cannot be depressed by the user.

[00181] To operate the system 10 using the actuator button 26, the user first moves the user interface portion 288 in a first axial direction, shown as being on the right in Figs. 65G and 65H. The user may need to move the user interface portion 288 approximately 10 mm or approximately 8 mm, although other suitable distances can be used. The movement of the actuator button 26 axially moves the locking tabs 290, 292 to release the contact surfaces 294, 296 with the button on the needle drive unit 286 and to allow the actuator button 26 to be moved from the raised position to the depressed position.

[00182] When the user moves the user interface section 288 in the distal control, the central spring tab 302 of the spring 284 of the button moves along the support surface 306 under the spring tab on the housing 20, wherein the first and second support surfaces 298, 300 are in engagement with the first and second support inclined surfaces 308, 310 on the housing 20. The forces acting on the spring 284 of the button are balanced by engagement with the support surface 306 under the spring tab and the first and second support inclined surfaces 308, 310 to ensure a smooth displacement or shift of the actuator button 26.

[00183] When the actuator button 26 and the button spring 284 reach the end of their axial displacement stroke, the central spring tab 302 and the first support surface 298 pass the end of the corresponding stops 312, 314 to lock the actuator button 26 from sliding back to its original position, as shown in Fig. 65H. In addition, when the actuator button 26 and the button spring 284 reach the end of their axial displacement stroke, the user touches the user interface portion 288 to move the actuator button 26 down to its pressed position. The actuator button 26 can be pressed by approximately 2 mm, and the minimum force required to press the actuator button 26 is about 3 N, and most preferably about 2.8 N, although other suitable distances and minimum forces can be used.

[00184] When the user presses the user interface portion 288 shown in Fig. 65A and 65B, the actuator button 26 rotates the needle drive unit 286 to release the needle drive unit 286 and thereby allows the needle drive unit 286 to move from the pre-use position to the use position. As shown in Fig. 65B, when the needle drive unit 286 moves to the use position, the locking tabs 290, 292 move along the underside of the button contact surfaces 294, 296 to prevent the actuator button 26 from bouncing upward. After the medication is delivered and when the needle drive unit 286 moves from the use position to the post-use position shown in Fig. 65C, the locking tabs 290, 292 disengage from the contact surfaces 294, 296 with the button, which allows the actuator button 26 to bounce back upward under the action of the button spring 284. After the needle drive unit 286 has completely moved to the post-use position shown in Fig. 65D, the actuator button 26 has completed moving from the depressed position to the raised position under the action of the biasing force of the button spring 284. When the needle drive unit 286 is in the post-use position, the spring tab 316 on the needle drive unit 286 is engaged with the actuator button 26 to lock the actuator button 26 from moving to the depressed position while the axial movement is still limited by the engagement of the spring tab 302 with the stops 312, 314. In this way, the actuator button 26 is locked after the delivery of the medicinal product is completed to represent a clear distinction between the used system and the unused system.

[00185] Additionally, if the user holds the actuator button 26 down while dispensing the medication, the correct dispensing and retraction will still be performed, but the actuator button 26 will not spring back up to the raised position until the button 26 is released.

[00186] In one aspect, the button spring 284 is made of plastic. The button spring 284 may also be a stamped metal spring, although any other suitable material may be used.

[00187] As shown in Fig. 68A-68G, instead of providing separate actuator button 26 and button spring 284, the spring can be formed integrally with the button 26. In particular, actuator button 320 according to a further aspect of the present invention includes an integral spring tab 322. The actuator button 320 also includes locking tabs 324, retaining tabs 326 and a rear heel 328. As shown in Fig. 68D and 68E, spring tab 322 is engaged with teeth 330 on the upper portion 22 of housing 20. During the transition of system 10 from the pre-use position to the use position, spring tab 322 moves past the stop of teeth 330, providing an axial spring force. The end of the spring tab 322 is engaged with a portion of the upper portion 22 of the housing 20 to provide a vertical spring force when the spring tab 322 is deflected. The actuator button 320 is designed to move smoothly between the sliding and lowering movements of the button 320, even if two separate movements occur, which is similar to the operation of the above-described button 26. During the transition between the position before use and the position of use, the button 320 rotates about the rear heel 328, wherein the holding tab 326 is in engagement with a portion of the needle drive unit 286 and, thereby, maintains the pressed position of the button 320 until the end of dose administration position is reached, similar to the case of the actuator button 26. The locking tabs 324 are deflected inward and enter into engagement with a portion of the needle drive unit 286, when the needle drive unit 286 moves to the end of dose administration position, thereby preventing further movement of the actuator button 320, similar to the case of the above-described actuator button 26.

[00188] Aspects of the present invention provide improvements over previous button designs. For example, the design 280 of the actuator button provides multiple surfaces for holding the needle drive unit 286 in place against the needle drive spring 106 until actuation, which reduces the likelihood of premature actuation from impact when dropped. The design 280 of the actuator button physically prevents the needle drive unit 286 from moving until actuation by holding it in an inclined (fixed) state such that the surfaces do not have room to separate and prematurely actuate.

[00189] In addition, by using a bending tab instead of using a simple buffer stop, the shifting forces of the button of the design 280 of the actuator button are more accurately controlled. This allows for an extension of the shifting strokes of the button 26, with more accurate control of the forces, which leads to a more ergonomic design. In addition, the design 280 of the actuator button ensures that the button 26 bounces back outward at the end of the injection, which gives the user additional visual, audible and tactile indication that the delivery of the drug is complete.

[00190] According to one aspect, the delivered volume of fluid in the system 10 is determined by the final position of the plunger relative to a point inside the housing, regardless of the actual filling volume, the internal diameter of the container and the initial position and length of the plug. The variability in dosing can be significant because the tolerances of the above-mentioned factors can be quite large. Aspects of the present invention make it possible to eliminate some or all of the mentioned tolerances from the dosing equation, which results in a more accurate and less variable injection volume of the drug.

[00191] Figs. 70A-70G show a spacer assembly 400 for use in connection with a drive assembly in accordance with one aspect of the present invention.

[00192] The elements of the tolerance chain in the spacer assembly 400 of the plug include the thickness (A) of the flange 402 of the inner plunger 404, the inner length (B) of the outer plunger 406 between the inner proximal end 408 and the inner shoulder 410, and the initial distance (C ₁ ) of the offset between the flange 402 of the inner plunger and the inner proximal end 408 of the outer plunger. This initial distance (C ₁ ) of the offset is preferably greater than the gap (C ₂ ) between the outer plunger 406 and the proximal end of the cylindrical sleeve 412 for the drug. The tolerance chain in the spacer assembly 400 of the plug also includes the inner diameter (D) of the cylindrical sleeve. Once assembled, the stopper spacer 414 and the outer plunger 406 are individual for a given volume of the medicinal product.

[00193] Fig. 70B-70G show the operation of the stopper spacer assembly 400. As shown in Fig. 70B, when the system is activated, both the inner and outer plungers 404 and 406 are released. The outer spring 416 presses the outer plunger 406 into the cylindrical sleeve 412, compressing the damping material 418 and the inner spring 420. The stopper 422 does not yet move relative to the cylindrical sleeve 412 due to the presence of a column of flowing medication.

[00194] Next, as shown in Fig. 70C, the outer spring 416 distally biases the outer plunger 406 and the cylindrical sleeve 412 to open a valve (not shown) at the distal end of the cylindrical sleeve 412, which creates fluid communication with the needle (not shown). Due to the incompressibility of the liquid medication, the stopper 422 cannot be displaced relative to the cylindrical sleeve 412 until the valve opens and a path for fluid into the needle is created for the patient.

[00195] Then, as shown in Fig. 70D and 70E, the inner spring 420 biases the inner plunger 404, the plug spacer 414 and the plug 422 to dispense the fluid.

[00196] Fig. 70F illustrates the end of drug delivery when the proximal flange 402 of the inner plunger 404 comes into contact with the inner shoulder 410 of the outer plunger 406, thereby stopping the displacement of the inner plunger 404 (and the spacer 414 of the plug and the plug 422) relative to the cylindrical sleeve 212 for the drug, and stopping the flow of the drug.

[00197] According to one aspect, as shown in Fig. 70G, cessation of displacement of the inner plunger 404 relative to the cylindrical barrel 212 for the drug includes an indicator of the end of dose administration by the system.

[00198] As shown in Fig. 71 and 72, the compressible spacer assembly 430 includes a front portion 432 of the spacer secured to the plug 434, an inner plunger 436, a rear portion 438 of the spacer, and a rotary shuttle 440. The inner plunger 436 can move translationally, but not rotate, relative to the front portion 432 of the spacer. Similarly, the rear portion 438 of the spacer can also move axially relative to the front portion 432 of the spacer, but not rotate relative to the front portion 432 of the spacer. As described in detail below, the rotary shuttle 440 first rotates and then moves translationally.

[00199] According to one aspect, the front portion 432 of the spacer is rigidly fixed to the plug 434. One skilled in the art will understand that many methods can be used to fix the front portion 432 of the spacer to the plug 434, such as gluing, mechanical fastening, or any other suitable design. The front portion 432 of the spacer preferably comprises a thread that is engaged with a mating thread in the plug 434.

[00200] When the spacer assembly 430 of the stopper is screwed into the stopper 434, an axial load is applied through the access holes 442 in the rear portion 438 of the spacer. Such a force can be used to press the stopper 434 forward, applying pressure to the flowable drug. This pressure causes the front (distal end) of the stopper 434 to deflect and press in the proximal direction, pushing back the rear portion 438 of the spacer and rotating the rotary shuttle into its "assembled" state. In other words, when the cylindrical sleeve for the drug is filled with the drug, and the plunger of the system applies an axial force to the drug through the spacer assembly 430, the distal end of the stopper 434 is deformed under the action of the pressure of the drug. During the delivery of the medicinal product, the drive unit (via the plunger) applies pressure to the rear section 438 of the spacer, which in turn applies torque to the rotary shuttle 440 via the screw surfaces 444 of the rear section 438 of the spacer. But the deformation of the plug under the action of the medicinal product ensures the action of a reverse or proximally directed force on the internal plunger 436, which prevents the rotation of the rotary shuttle 440.

[00201] According to one aspect, the axial reaction force acting on the inner plunger 436 can be increased by increasing the length of the inner plunger 436.

[00202] After the delivery of the drug is completed, as shown in Fig. 73, the pressure on the stopper 434 is reduced, allowing the distal end of the inner plunger 436 to move in a distal direction. This distal movement allows the rotary shuttle 440 to rotate. The continued action of the axial force applied by the drive assembly rotates and distally moves the rotary shuttle 440 due to the interaction of the helical surfaces 444 in the rear portion 438 of the spacer with the corresponding cam tabs 446 of the rotary shuttle 440. According to one aspect, this final movement of the rotary shuttle 440 causes the drive assembly to initiate the retraction of the needle.

[00203] As shown in Figs. 74 and 75, a limiting member 452 is disposed with the drive assembly in accordance with one aspect of the present invention. The limiting member 452 controls the timing of the final displacement of the needle drive units 96, 220 after the delivery of a dose of the drug is completed. Instead of pivoting about a fixed support, the limiting member 452 is free to swing. After the plunger is sufficiently displaced in the distal direction so that the gap is aligned with the limiting member 452 (as shown in Figs. 74 and 75), the limiting member 452 is displaced laterally into the gap due to the action of a spring force on the needle drive unit 96, 220 and a beveled surface 454 on the rear side of the tab of the limiting member 452, which is engaged with the needle drive unit (best shown in Fig. 75). After the limiting element no longer holds the needle drive unit 96, 220, the needle drive unit 96, 220 can complete the axial movement to the position after use. In addition, as shown in Fig. 75, the limiting element 452 is displaced to the rear side of the cylindrical sleeve portion of the container 14, which minimizes the chain of tolerances of the various components and increases the accuracy of the dose.

[00204] Fig. 76-78 shows a spacer assembly 460 in accordance with a further aspect of the present invention. The spacer assembly 460 shown in Fig. 76-78 provides for eliminating the effect of accumulation of manufacturing tolerances by adjusting the spacer assembly, which allows each system to inject the same amount of drug.

[00205] As shown in Fig. 77, the spacer assembly 460 includes a plug 462 and a plug spacer 464. The plug spacer 464 includes a fixed spacer member or a fixed spacer 466, which is rigidly connected to the plug 462, and an adjustable spacer member or an adjustable spacer 468, which is rotationally displaceable in one direction relative to the fixed spacer 466.

[00206] One skilled in the art will understand that many methods can be used to secure the fixed spacer 455 to the plug 462, such as adhesives, mechanical fasteners, or any other suitable design. The fixed spacer 466 preferably comprises one or more external threads that engage one or more mating threads in the plug 462. According to one aspect, the adjustable spacer 468 has a distal rod with an external thread 470. The thread 470 of the distal rod engages an internal thread 472 in the fixed spacer 466 (best shown in Fig. 78) to pivotally control the axial displacement of the adjustable spacer 468 relative to the fixed spacer 466.

[00207] As shown in Fig. 76 and 77, the fixed strut 466 includes radially spaced stops 474, and the adjustable strut 468 includes a spring locking tab 476, the free end of which is engaged with a selected one of the stops 474 to prevent rotation and axial movement of the adjustable strut 468 toward the fixed strut 466. The free end of the spring locking tab 476 is configured to pass over the stops 474 in one direction to allow rotation and proximal axial displacement of the adjustable strut 468 from the fixed strut 466.

[00208] Regardless of the variations in the dimensions of the stoppers and containers, the adjustable spacer 468 can be adjusted relative to the fixed spacer 466 to ensure a constant axial length of the stopper assembly 460.

[00209] As shown in Fig. 78, when the container is filled, an axial load can be applied to the adjustable spacer 468 (and hence the fixed spacer 466 and the stopper 462), such as the load that would occur when installed in the system 10, 200. After the axial load is applied, the adjustable spacer 468 can be moved back in the proximal direction to provide a constant gap 478 between the proximal end of the cylindrical sleeve for the drug and the proximal end of the adjustable spacer 468, thereby taking into account the deflections of the glass cylindrical lens for the drug and the compressibility of any entrapped air. In other words, the spacer assembly 460 allows the adjustable spacer 468 to have a predetermined set position relative to the container 14, regardless of the changing parameters of the container 14 and the length of the stopper. Accordingly, the initial position of the spacer unit 460 is at a predetermined distance from the container 14, and the final position of the spacer unit 460 is also at a predetermined distance from the container 14, so that the stroke of the plug 462 is determined by the effective length of the plungers 52, 54 of the drive unit 12.

[00210] Fig. 79 and 80 show a support post 482 and a cap 484 of an automatically adjustable spacer 486 according to one aspect of the present invention. The support post 482 includes a support portion 488 and an axially extending post 490. According to one embodiment, the support post 482 includes a plurality of columnar projections 491, each of which has a plurality of ratchet teeth 492 located on their proximal portions. At the proximal end of each of the plurality of ratchet teeth 492, a locking tooth 493 is located. The cap 484 is hollow, and the distal end of the cap 484 includes one or more axial springs 494. According to one aspect, the axial springs 494 are curved cantilever tabs formed during the molding process of the cap 484. According to another aspect, a separate biasing element, such as a compression spring, can be used in the automatically adjustable spacer 486. When assembled with the support post 482, the springs 494 engage with the support portion 488 and maintain the original gap between the support post 482 and the cap 484. According to one aspect, the springs 494 are absent. The cap 484 also includes a plurality of flexible cantilever tabs or plates 496, each of which has a free proximal section with a plurality of internal ratchet teeth 497. The proximal end of each flexible tab 496 includes a leg 498.

[00211] Fig. 81B shows a cap of an automatically adjustable spacer placed inside a proximal recess of a stopper 494 on a proximal portion of a cylindrical sleeve for a drug. The support post 482 is installed in the hollow cap 484, wherein the support portion 482 is engaged with the stopper 494, and the legs 498 are located outside the proximal end of the cylindrical sleeve.

[00212] During use, as shown in Figs. 81A and 81B, the cap 484 is displaced in a distal direction relative to the support post 482 (as well as the stopper 494 and the cylindrical sleeve) until the proximal end of the cap 484 is flush with the end of the cylindrical sleeve for the drug. This action forces the legs 498 to engage with the inner surface of the cylindrical sleeve and to move radially inward, and thereby presses the ratchet teeth 492 into a locking engagement with the ratchet teeth 497. The locking tooth 493, the engagement of the ratchet teeth 492 and 497 and the engagement of the legs 498 with the inner surface of the cylindrical sleeve block the displacement of the cap 484 relative to the support post 482. In this way, the automatically adjustable spacer 486 can compensate for differences in plugs, cylindrical sleeve diameters and drug filling volumes in order to automatically ensure the position of the support surface flush with the proximal end of the cylindrical sleeve for the drug.

[00213] One aspect of the present invention is a spacer assembly 486 that is located close to the stopper in the container inside the system. The design of the spacer is such that its effective length can be adjusted to allow dosing of an accurate amount of the drug. The adjustment of the length is intended to compensate for manufacturing tolerances inside the container, the filling volume and, especially, the length of the stopper, which can give a total of up to 1/3 of the variability in the delivered dose, when using a non-adjustable spacer. The length of the spacer can be adjusted in several ways, depending on the particular aspect. The length of the spacer can be self-adjusting, based on its location relative to the back of the container, this length can be adjusted by assembly equipment during the final assembly of the main container into a subassembly, and the spacer can be formed as an integral part of the stopper and adjusted as a subassembly before filling. The adjustable spacer 486 allows for injecting a more accurate volume of fluid than a non-adjustable stopper.

[00214] Figs. 82-87 show an actuator assembly 500 for a drug delivery system in accordance with one aspect of the present invention. The actuator assembly 500 includes an actuator button 506, a container 508, a needle actuator assembly 510, a trigger or locking and releasing actuation plate 512, a lead screw 514 and a plunger 516. The lead screw includes a drum section 518 with outer radially extending plates 520, and, as best shown in Figs. 84 and 85 and described in detail below, a section 522 with a screw thread. Prior to actuation, as best shown in Figs. 83 and 86, one end 513 of the trigger plate 512 is engaged with one of the plates 520 to prevent rotation of the lead screw 514.

[00215] According to one aspect, as shown in Fig. 84-86, the portion 522 with the screw thread of the lead screw 514 is engaged with the internal thread of the nut 524 connected to the plunger 516. According to another aspect, the nut and its internal thread are formed integrally with the plunger as a single structure. In addition, a spring 526 of constant stiffness is accommodated inside the drum portion 518 and biases the lead screw 514 in the direction of rotation. According to one aspect, the spring 526 is fixed to the base cover 504. According to another aspect, as shown in Fig. 84-86, the drive unit housing 528 is located inside the system, and the spring 526 is fixed to the drive unit housing 528.

[00216] Unlike a coil spring, such as a compression spring, which has a force characteristic proportional to its displacement, the constant rate spring 526 and the like maintain a relatively constant or uniform force characteristic over its entire long working length. The uniform force characteristic advantageously provides an injection force that is proportional to the spring force. This property will provide a constant or uniform injection force and, therefore, a substantially constant injection rate of the drug. Although in Fig. 86 the spring 526 is shown to have only two turns of material, it will be apparent to one skilled in the art that more or fewer turns can be used. The assembler preferably tightens the spring 526 when the drive unit 500 is assembled, and the spring 526 is stored in the tightened position until actuation.

[00217] After the system is activated, the needle drive assembly 510 is released for axial displacement (to the right in Figs. 82-85) from the pre-use position to the post-use position under the action of the biasing member 530 (best shown in Fig. 83). During this displacement, the needle drive assembly 510 presses on the second end 532 of the trigger plate 512 and rotates the trigger plate 512 counterclockwise, as shown in Fig. 87. This counterclockwise rotation of the trigger plate 512 releases its first end 513 from engagement with the plate 520. After the first end 513 is disengaged from the plate 520, the spring 526 unwinds and causes the lead screw 514 to rotate, which, in combination with the nut 524, advances the plunger 514 to dose the medicinal product.

[00218] When the lead screw 514 rotates, the rotation of the drum section 518 and the plates 520 is visually observed through the window 534 in the housing. This window 534 shows the movement of the screw in a way that is more visual than visual observation of the linear movement of the plug 536 in the container 508. In fact, this rotational movement is many times more sensitive than the linear movement. It will be obvious to a person skilled in the art that the exact value of the gain or amplification depends on the pitch of the thread in the section 522 with the screw thread of the lead screw 514, the diameter of the drum section 518 and the number of plates 520 on the drum section 518.

[00219] Fig. 88-93 shows a drive unit 600 for a drug delivery system according to a further aspect of the present invention. The drive unit 600 performs the function of storing the mechanical energy of the spring and activating it when turned on. The drive unit 600 includes a cylindrical sleeve 601 for a drug, a plug 602 disposed with the possibility of sliding in the cylindrical sleeve 601, a first valve plunger 603, a second valve plunger 604, a first rotating nut 605 and a second rotating nut 606. The drive unit 600 also includes a rotary indicator 607, a locking element 608, a spring 609 of constant stiffness disposed inside the rotary indicator 607 and a trigger or locking and releasing plate 610 of actuation. The drive unit 600 is at least partially located within a housing 611, which can be installed in a drug delivery system.

[00220] Between the housing 611 and the rotary indicator 607, inside the drum section 616 of the rotary indicator 607, a spring 609 of constant stiffness is enclosed. The inactive state of the drive unit is such that energy is provided by unwinding the spring 609 and geometrically coupling this energy with the housing 611, the rotary indicator 607 and the trigger plate 610. When the drive unit 600 is transferred to the inoperative state, the spring unwinds and converts mechanical energy into a rotational movement of the rotary indicator.

[00221] The telescopic multi-component plunger is oriented along the force axis between the cylindrical sleeve 601 for the drug and the rotary indicator 607. The rotary indicator 607 comprises a threaded rod 618. According to one aspect, the thread is double-start and has either a square or rectangular profile. The multi-component telescopic plunger comprises a two-component threaded nut (first rotating nut 605 and second rotating nut 606) and a two-component plunger (first valve plunger 603 and second valve plunger 604). The second rotating nut 606 is a threaded rod that mates with the rotary indicator 607 and the first rotating nut 605 and contains matching threads on its internal and external surfaces (internal and external threads, respectively) for mating with them. The second rotating nut 606 also contains an annular flange 620 (best shown in Fig. 92) at its proximal end, which touches the bottom of the second plunger 604 of the valve. The second rotating nut 606 can be screwed along the power axis. The first rotating nut 605 is also a threaded rod that contains a thread on its internal diameter, corresponding to the external thread of the second rotating nut 606, in order to mate with the second rotating nut 606.

[00222] According to one aspect, at one end, the first rotating nut 605 comprises a hexagonal projection that is pressed into the first valve plunger 603 to rigidly connect the first valve plunger 603 to the first rotating nut 605. In the drive assembly 600, the first rotating nut cannot rotate and will only move translationally when the power module subassembly is driven.

[00223] The second valve plunger 604 is a hollow cylindrical component with a small shoulder 622 at its distal end, a large shoulder 624 at its proximal end, and an elongated L-shaped console 626 (best shown in Fig. 93) protruding from the large proximal shoulder 624. According to one embodiment, the small shoulder 622 is split and contains four leaf cantilever tabs or leaf springs 623 that allow the shoulder to unbend and mate with the first valve plunger 603. The inner surface of the second plunger 604 of the valve has an undercut along its entire length, ending at its proximal end with a step 628, protruding radially inward from the large flange 624. The step 628 engages with the second rotating nut 606 inside the telescopic subassembly.

[00224] The first valve plunger 603 is secured to the plug 602 and is also a hollow cylindrical component that mates with the second valve plunger 604. In particular, the first valve plunger 603 comprises a cylindrical projection 630 at its distal end for mating with the plug 602. According to one aspect, as best shown in Fig. 89, four through grooves 632 are located on the proximal quadrants of the first valve plunger 603 for mating with leaf springs or tabs 623 and a portion 622 of a small shoulder of the second valve plunger 604. Both the first and second valve plungers 603 and 604 can move freely.

[00225] Telescoping is achieved when the constant spring 609 unwinds and the rotary indicator 607 begins to rotate. The threaded connection between the rotary indicator 607 and the second rotating nut 606 forces the second rotating nut 606 to rotate. But, since the second rotating nut 606 contains a thread for the first rotating nut 605, which cannot rotate and experiences resistance to translational movement in the distal direction due to the pressure caused by the drug in the cylindrical sleeve 601, then the second rotating nut 606 will be displaced proximally and reach the stop against the radially inwardly protruding shoulder 628 of the second valve plunger. The second plunger 604 of the valve is blocked from proximal displacement by the housing 611. Then, and with the continuation of rotation of the rotary indicator 607, since the second rotating nut 606 is threadedly mated with the first rotating nut 605 (which cannot rotate), the first rotating nut 605 moves progressively in the distal direction and presses on the first plunger 603 of the valve (and the plug 602) to dose the drug from the cylindrical sleeve 601.

[00226] The first valve plunger 603 is displaced distally relative to the second valve plunger 604 until sections of the small shoulder 622 (respectively located on the distal ends of the leaf springs or tabs 623 of the second valve plunger 604) do not engage with the corresponding proximal ends of the grooves 632 of the first valve plunger 603. This fixes the relative position of the first and second valve plungers 603 and 604, with continued rotation of the rotary indicator 607, both valve plungers are translated in the distal direction, and at the same time push the second rotating nut (due to its proximal engagement with the shoulder 624).

[00227] The initial and final position of the telescopic plunger and, consequently, the dose of the medicinal preparation are controlled by the rectangular shape of the thread of the threaded rod 618 of the rotary indicator 607, the threaded rod on the drum section 616 of the rotary indicator 607 and the stepped pin, which acts as the locking element 608. According to one aspect, the threaded rod on the drum section 616 of the rotary indicator 607 is single-start, and, since the remaining components in the telescopic chain have double-start threads, the axial stroke of the other threaded components is twice the axial stroke of the locking element 608 relative to the rotary indicator.

[00228] According to one embodiment, the lock 608 is cylindrical and is characterized by a round tip at one end and a cylindrical shoulder at the other end. The thread on the outer surface of the drum portion 616 of the rotary indicator together with the groove and undercut 636 at the base of the housing 611 captures the lock 608 in place, allowing it to shift parallel to the force axis. Thus, when the spring 609 is released and the rotary indicator 607 is rotated, the lock 608 moves translationally and also forms a fixed stop when the distal end of the thread on the outer surface of the drum portion 616 of the rotary indicator is reached.

[00229] One advantage of aspects of the drive assembly 600 includes the use of a constant spring 609, the mechanical energy of which is converted into a substantially constant linear force acting on the drug in the cylindrical barrel 601. In turn, this generates a uniform rate of delivery of the drug. Another advantage is that, when using a telescopic plunger driven by a thread, the drive assembly can provide a space saving of up to 0.75 inches (29.5 mm) in a straight line, compared to other plunger designs. In addition, the drive assembly provides control of the dose of the drug through the initial and final mechanical limitation in the same component.

[00230] As noted above, other drug delivery systems use a compression coil spring that develops a maximum force at the moment of actuation, which eventually decreases as the spring expands. The weakening of the force on the plunger translates into a variable delivery time of the drug and the release pressure of the drug. By using a constant spring, the force applied to the plunger is constant from the beginning to the end of the dosing. In addition, the distance that the coil spring must travel in addition to the length that the static plunger must move within the drug container can lead to an elongation of the assembly. In contrast, in embodiments of the present invention, the constant spring is radially limited and does not require any additional space before or after actuation. In addition, aspects of the telescopic plunger provide that the length of the plunger can be significantly reduced compared to the length of the static plunger.

[00231] Previous drug delivery systems have variable dosing accuracy because the mechanical components that deliver the drug create a geometric dependency by abutting a container that cannot be manufactured to tight tolerances. Some embodiments of the present invention control the timing of the start and end of the plunger translation by means of a thread shape in a rotary indicator and the use of a constant spring.

[00232] The drive assembly creates a space-saving geometry, in addition to precise control of time, volume and pressure in the drug delivery device, resulting in a more compact and precise drug delivery device.

[00233] Some aspects of the drive assembly implement three rotating threaded rods to achieve a linear space saving of up to about 0.75 inches (19.5 mm). In other aspects, the same concept can be used using two rotating threaded rods and, as a result, a space saving of about 0.5 inches (12.7 mm) can be achieved. Some aspects of the present invention convert the rotational energy of a constant spring into a forced translational movement of a plunger.

[00234] Fig. 94-100 shows a spacer assembly 660 according to a further aspect of the present invention. The spacer assembly 660 is similar to the spacer assembly 460 described above and shown in Fig. 76-78, and operates in a similar manner, with similar advantages. The spacer assembly 660 includes a fixed spacer 666 and an adjustable spacer 668. The fixed spacer 666 is configured to be received in the plug 462, and the bosses 670 engage with the plug 462 to secure the fixed spacer 666 within the plug 462, although other suitable securing structures, such as threads, can be used. The fixed strut 666 comprises an internal thread 672 that receives an external thread 678 of the adjustable strut 668. The fixed strut 666 includes a plurality of stops 674 that are located on the helical portion of the fixed strut 666. The adjustable strut 668 includes a spring locking tab 676 that engages with one of the projections 674 to prevent rotation and axial movement of the adjustable strut 668 relative to the fixed strut 666. The spring locking tab 676 is shaped to pass over the stops 674 in one direction to allow rotation and axial displacement of the adjustable strut 668 from the fixed strut 666. The adjustable strut 668 can initially be attached to the fixed strut 666 using a thread 672, 678 by applying a force to the top of the spring lock tab 676, which presses the spring lock tab 676 away from the stops 674 to allow the spacers 666, 668 to be secured to each other. Accordingly, similar to what was described above in connection with the spacer assembly 460, the adjustable spacer can rotate with movement in one axial direction to adjust the length of the spacer assembly 660.

[00235] As also shown in Fig. 94-100, the spacer assembly 660 further comprises a washer 680 configured to be received in the adjustable spacer 668 and secured thereto. Instead of providing a plurality of sizes of adjustable spacers 468, 668, a plurality of sizes of washers 680 can be provided to compensate for a plurality of different filling volumes in the container 14. The washer 680 can be secured to the adjustable spacer 668 by means of a connector 682 extending from the washer 680, which is received in the adjustable spacer 668 by means of a snap-fit, although other suitable fastening structures can be used. The central section 684 of the fixed strut 666 is configured to be engaged when the adjustable strut 668 rotates relative to the fixed strut 666 in order to prevent the fixed strut 666 from rotating together with the adjustable strut 268. The central section 684 of the fixed strut 666 is accessible through an opening in the washer 680.

[00236] Elements of one disclosed aspect may be combined with elements of one or more other disclosed aspects to form various combinations that are considered to be within the scope of the present invention.

[00237] Although the present invention has been described with respect to its exemplary constructions, the present invention can be further modified within the spirit and scope of the present invention. Therefore, it is intended that the present application cover any modifications, applications or modifications of the invention using its general principles. It is also intended that the present application cover such departures from the present disclosure as are made within the known or special practice in the art to which the present invention pertains and which do not go beyond the scope of the appended claims.

Claims (15)

1. A drug delivery system for injecting a medicinal product, the system comprising: a container designed to contain a medicinal product, wherein the container comprises a stopper designed to move within the container and a lid; drive unit containing: a plunger element configured to engage and move the stopper within the container, wherein the plunger element has a first position and a second position axially spaced from the first position, wherein the plunger element comprises an outer plunger and an inner plunger configured to move away from the outer plunger, wherein at least a portion of the inner plunger is received within the outer plunger when the plunger element is in the first position; a constant-rigidity spring configured to move the plunger element from the first position to the second position, a lead screw, wherein the lead screw comprises a drum section such that the constant stiffness spring is accommodated in the drum section of the lead screw and is configured to shift the lead screw in the direction of rotation, wherein the rotational movement of the lead screw causes an axial shift of the plunger element from the first position to the second position; and a driving element located at the lead screw, wherein the driving element is formed from at least one nut and is configured to engage and axially move the outer plunger, wherein the axial movement of the outer plunger is configured to ensure axial movement of the inner plunger; a housing configured to contain at least a portion of the container and the drive unit; and a needle drive assembly comprising a needle configured to be mounted in fluid communication with a container, wherein the needle is movable from a first position and a second position spaced apart from the first position, wherein the outer plunger comprises a threaded section configured to engage the drive unit, and wherein the housing additionally comprises at least one window through which at least part of the drum section is visible to the user. 2. The system of claim 1, wherein the drum section comprises a helical section extending from the drum section so that the constant spring is received in and engaged with the drum section. 3. The system of claim 1, wherein the inner plunger comprises a plurality of tabs, and wherein the outer plunger forms a plurality of grooves, wherein a portion of each of the plurality of tabs of the inner plunger is received by a corresponding one of the plurality of grooves of the outer plunger. 4. The system according to claim 1, wherein the threaded section of the outer plunger comprises a first rotating nut connected to the outer plunger, and wherein the drive element comprises a second rotating nut engaged with the first rotating nut and the lead screw. 5. The system according to claim 1, wherein rotation of the lead screw causes simultaneous rotation of the drum section, so that rotation of the drum section is visible through at least one window in the housing, so that rotation of the drum section shows the stroke of the lead screw.