WO2007107559A1

WO2007107559A1 - Flat assembly for medication delivery device

Info

Publication number: WO2007107559A1
Application number: PCT/EP2007/052631
Authority: WO
Inventors: André LARSEN
Original assignee: Novo Nordisk AS
Current assignee: Novo Nordisk AS
Priority date: 2006-03-20
Filing date: 2007-03-20
Publication date: 2007-09-27
Anticipated expiration: 2008-09-20

Abstract

The present invention relates to an assembly for a medication delivery device, the assembly comprising means for visually displaying information to a user of the medication delivery device, a mechanical drive mechanism adapted to generate or transfer the required force necessary for expelling a medicament from a medicament containing cartridge when said medicament containing cartridge is positioned in the medication delivery device, and an electronic control circuit operatively coupled to the display means and/or the mechanical drive mechanism, wherein at least part of the electronic control circuit is arranged on a carrier, and wherein the carrier, the display means and the mechanical drive mechanism are arranged in a manner so that they form a sandwich construction in combination.

Description

FLAT ASSEMBLY FOR MEDICATION DELIVERY DEVICE

FIELD OF THE INVENTION

The present invention relates to an assembly for a medication delivery device, the assembly comprising a flat panel display, a PCB and a drive mechanism arranged in a sandwich construction.

BACKGROUND OF THE INVENTION

The rotational symmetry of conventional medication delivery devices puts strong limitations to the mechanical construction of the internal parts constituting conventional medication delivery devices.

US 5,925,021 discloses a medication delivery device, such as a pen-type injector, jet injector, medication pump, inhaler, spray or the like. The medication delivery device of US 5,925,021 has a microprocessor coupled to the device that records the date, the time, and the amount of each medication administration. The microprocessor may also be coupled to a display to indicate the amount of medication to be administered.

For the user of a device similar to that suggested in US 5,925,021 it is a disadvantage that the display for providing information to the user of the device is arranged on an exterior surface of an essentially cylindrical pen-type medication delivery device. A consequence of this positioning of the display is that the device of US 5,925,021 will role over in case the pen-type device is positioned on a plane surface with the display arranged upwards. Such plane surface could be the upper side of a table. The result of this rolling over is that the pen- type device suggested in US 5,925,021 will end up having the display facing at least partly downwards whereby the information provided on the display becomes unreadable for the user of the device.

A medication delivery device suggested in US 6,277,099 also contains a display. However, the medication delivery device of US 6,277,099 also suffers from the above-mentioned problems of rolling over whereby the information provided on the display faces downwards thereby becoming unreadable for the user of the device.

It is an object of the present invention to provide an optimal arrangement of a flat panel display, a PCB and a drive mechanism so as to provide an assembly suitable for being mounted in non-circular pen-like medication delivery devices. The present invention seeks at arranging a flat panel display, a PCB and a drive mechanism in a sandwich construction.

It is an advantage of the present invention that the mechanics and electronics constituting the interior part of a medication delivery device can be arranged in a space saving manner whereby the overall dimensions of the medication delivery device can be reduced to a minimum.

It is a further advantage of the present invention that the assembly process becomes simpler due to the sandwich construction which also ensures an optimal fill factor between mechanics and electronics.

Furthermore, it is an advantage of the present invention that the space saving arrangement of the mechanics and electronics ensures that the fully integrated assembly comprises a flat panel display, a PCB with associated electronics and a mechanical drive mechanism for expelling a set dose of medicament from a medicament containing cartridge can be fully integrated in the housing of the medication delivery device without suffering from the above- mentioned disadvantages, i.e. the pen-type medication delivery device tends to roll over when positioned on a substantially plane surface.

SUMMARY OF THE INVENTION

The above-mentioned object is complied with by providing, in a first aspect, an assembly for a medication delivery device, the assembly comprising

- means for visually displaying information to a user of the medication delivery device,

a mechanical drive mechanism adapted to generate or transfer the required force necessary for expelling a dose of medicament from a medicament containing cartridge when said medicament containing cartridge is positioned in the medication delivery device, the mechanical drive mechanism comprising a linear shaped piston rod adapted to move along a centre axis of the medicament containing cartridge, the drive mechanism further comprising a gearing comprising one or more rotatably mounted gear elements being arranged to rotate in the plane substantially parallel to a carrier, and

an electronic control circuit operatively coupled to the display means and/or the mechanical drive mechanism wherein the electronic control circuit is at least in part arranged on the carrier, said carrier being arranged between the display means and the mechanical drive mechanism in a manner so that the display means, the carrier and the mechanical drive mechanism form a sandwich construction in combination.

In a second aspect, the present invention relates to an assembly for a medication delivery device, the assembly comprising

display means for visually displaying information to a user of the medication delivery device,

a mechanical drive mechanism adapted to generate or transfer a required force necessary for expelling a set dose of medicament from a medicament containing cartridge when said medicament containing cartridge is positioned in the medication delivery device, the mechanical drive mechanism comprising a piston rod adapted to provide the required force in an axial direction of the medicament containing cartridge, the drive mechanism further comprising one or more rotatably mounted drive elements being arranged to rotate in a plane substantially parallel to a carrier, and

an electronic control circuit operatively coupled to the display means

wherein at least part of the electronic control circuit is arranged on the carrier, and wherein the carrier, the display means and the mechanical drive mechanism are arranged in a manner so that they form a sandwich construction in combination.

The one or more rotatably mounted drive elements may be arranged, upon rotation, to transfer forces between moveably mounted elements of the drive mechanism. One of these moveably mounted elements may be the piston rod, gear wheels etc.

Mechanical drive means should be interpreted as a mechanism for manually administering a dosage of medicament. Thus, in order to expel a set dose of medicament the medication delivery device and thereby the mechanical drive mechanism is user energized. By user energized is meant that the user of the medication delivery device provides the required force to expel a set dose of medicament. Alternatively, the user may energize some sort of resilient member, such as a linear spring or a torsion, whereby energy is stored in the medication delivery device. This stored energy is released during expelling of a set dose of medicament. According to the second aspect, the carrier may be arranged between the display means and the mechanical drive mechanism. Alternatively, the mechanical drive mechanism may be arranged between the display means and the carrier.

The display means may comprise a flat panel display, such as a LCD. The carrier may comprise a PCB. The PCB may be of the rigid type or the flexible type.

The piston rod may comprise an essentially non-bendable rod comprising a toothed region adapted to mesh with one or more of the rotatably mounted gear or drive elements so as to perform a translational movement in response to a rotational movement of a rotatably mounted gear or drive element. Alternatively, the piston rod may comprise a plurality of elements, said plurality of elements being displaceable or rotatably mounted relative to each other and being arranged in a manner to that the effective length of the piston rod is adjustable by displacing at least two elements relative to each other.

The assembly may further comprise sensor means adapted to provide a measure for an expelled and/or set dose of medicament. Such sensor means may comprise an encoder arranged on the carrier, the encoder being in electrical communication with the electronic control circuit. The encoder may measure an angular rotation of for example a gear wheel which is directly or indirectly coupled the piston rod. Such rotation of a gear wheel or another type of rotatably mounted drive element is preferably in the plane of the carrier. Thus, the sensor means is preferably arranged to measure movements in the form of displacements, rotations etc., said movements being in the plane of the carrier.

Other types of sensors capable of measuring a displacement, rotation or a change of lengths of the piston rod may also be applied. Such sensor may be of mechanical, electrical, magnetic or optical nature.

The sandwich construction comprising the display means, the carrier and the mechanical drive mechanism may have a total height smaller than 25 mm, such as smaller than 20 mm, such as smaller than 15 mm, such as smaller that 10 mm.

In a third aspect, the present invention relates to a pen-like medication delivery device comprising an assembly according to the first aspect of the present invention. The pen-like medication delivery device may comprise a housing extending in an axial direction of the medication delivery device, the housing having, in cross-sectional planes perpendicular to the axial direction, a non-circular outer surface profile. The housing may comprise an opening or a transparent region arranged in a substantially plane surface part of the housing, the opening/transparent region being adapted to be aligned with the display member of the assembly.

BRIEF DESCRIPTION OF THE INVENTION

The present invention will now be explained with reference to the accompanying figure in that

Fig. 1 shows the general concept underlying the present invention and

Fig. 2 shows a more detailed depiction of the concept of the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and will be described in detail herein. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.

DETAILED DESCRIPTION OF THE INVENTION

In its most general aspect the present invention relates to a sandwich construction comprising a PCB, with an electronic control circuit arranged thereon, sandwiched between a flat panel display, such as a LCD, and some sort of mechanical driving mechanism being capable of expelling a medicament, such as insulin, from a medicament containing cartridge positioned within a housing encapsulating the medication delivery device. It should be noted that the sandwich construction may also comprise a mechanical driving mechanism sandwiched between a carrier and a flat panel display. Thus, the present invention is not limited to a specific order of the elements constituting the sandwich construction. However, in the following, the present invention will be explained from the perspective of a sandwich construction involving a PCB sandwiched between a flat panel display and some sort of mechanical driving mechanism.

The sandwich construction according to the present invention will fit into a medication delivery device housing having a non-circular cross-sectional shape. This shape can for example be an essentially elliptical cross-sectional shape.

Compared to conventional arrangements including cylindrical pen-like medication delivery devices the sandwich construction according to the present invention offers a space efficient construction in that the construction leaves essentially no free space between the flat panel display, the PCB and the mechanical drive mechanism. Even further, assembling of the assembly according to the present invention is simpler compared to conventional arrangements.

The flat panel display is preferably a surface mountable device with connection legs being directly connectable to the PCB. Similarly, the mechanical drive mechanism can advantageously be formed with a plane surface abutting, but not short-circuiting, the PCB.

On the PCB the necessary control electronics for the medication delivery pen is provided. Thus, the electronics for controlling the flat panel display, which might be a LCD array, electronics, such as a microprocessor, for processing signals from various sensors, such as sensors for cartridge identification, cartridge content etc., is arranged on the PCB.

The mechanics for driving the drive mechanism for expelling medicament from the medicament containing cartridge is a purely mechanically driven arrangement. Thus, the drive mechanism according to the present invention can involve a telescopic piston rod comprising displaceable plates whereby the effective length of the telescopic piston rod can be changed by displacing the displaceable plates relative to each other. The relative displacement between the plates can be provided by various means, such as for example a gear arrangement. The force assisting the user of the medication delivery device can be provided by a spring element, such as a linear or torsion spring. Alternatively, no force assisting member is provided where the force required to expel a set dose of medicament is purely provided by the user of the medication delivery device.

Referring now to Fig. 1 a display member 1, a PCB 2, and a mechanical drive mechanism 3 mounted within a housing 4 of a pen-like medication delivery device is depicted. Visual access to the display member is provided through an opening in the housing of the medication delivery device. As illustrated in Fig. 1 the PCB 2 is sandwiched between the display member 2 and the mechanical drive mechanism 3. The display member, which preferably is a LCD array, is directed mounted on the PCB 2. In addition, the PCB 2 may carry the necessary electronics for controlling the operation of the medication delivery device, including a controller for controlling the information provided to the display member and handling/processing signal from sensors provided in the medication delivery device. Such sensors can be sensors for measuring the axial position of a piston rod thereby providing a measure of an expelled dose of medicament. This information can be displayed on the LCD array to inform the user of the amount of expelled medicament. Also, the amount of accumulated, expelled medicament can be displayed on the LCD. Similarly, the remaining amount of medicament in the cartridge can be expelled whereby the user of the medication delivery device is warned in good time before the cartridge needs to be replaced.

The overall dimensions of the sandwich construction (I x w x h) are typically around 45 x 17 x 15 mm. However, dimensions as small as 30 x 15 x 10 mm (I x w x h) should also be within reach.

Referring now to Fig. 2 a more detailed depiction of the sandwich construction according to the present invention is shown. As seen the mechanical drive mechanism 3 is operatively connected to the PCB 2 in that a sensor 6 arranged on the PCB monitors the translational movement of the piston rod 7. The translational movement if the piston rod 7 is caused by its coupling to the rotatably mounted gear-wheels 8. Thus, upon rotation of the gear-wheels 8 the piston rod 7 is caused to undergo a translational whereby a piston positioned in a medicament containing cartridge (not shown) is moved towards the proximal end of the cartridge whereby a set dose of medicament can be expelled. The coupling between the piston rod 7 and one of the gear-wheels is provided by a toothed region on the piston rod 7 adapted to mesh with one of the rotatably mounted gear-wheels. As depicted in Fig. 2 the mechanical drive mechanism 3 contains a plurality of gear-wheels, one of them being arranged to mesh with the piston rod whereas others are arranged to provide gear transmission between various wheels.

The piston rod depicted in Fig. 2 is a substantially rigid piston rod. By substantially rigid is meant that the length of the piston rod is fixed and thereby non-adjustable. An alternative form of the position rod can be a segmented piston rod where the rod itself is constituted by a plurality of internally displaceable segments. By displacing or rotating these segments relating to each other the effective length of the piston rod is adjustable. Thus, with such a piston rod the piston in the cartridge is moved towards the proximal end of the cartridge by increasing the overall length of the piston rod. When the cartridge is empty the piston rod is withdrawn by reducing the overall length of the piston rod.

The overall length of the piston rod can be adjusted by displacing rod segments relative to each other. Such displacement can be achieved by applying a compact gear-wheel arrangement where rotation of a number of gear-wheels relative to each other displaces to neighbouring rod segment relative to each other. It may also be that the piston rod segments are rotatably mounted relative to each other. Thus, by rotating piston rod segments relative to each other, the overall length of the piston rod can be either increased or decreased.

Claims

1. An assembly for a medication delivery device, the assembly comprising

- a mechanical drive mechanism adapted to generate or transfer a required force necessary for expelling a set dose of medicament from a medicament containing cartridge when said medicament containing cartridge is positioned in the medication delivery device, the mechanical drive mechanism comprising a piston rod adapted to provide the required force in an axial direction of the medicament containing cartridge, the drive mechanism further comprising one or more rotatably mounted drive elements being arranged to rotate in a plane substantially parallel to a carrier, and

an electronic control circuit operatively coupled to the display means

2. An assembly according to claim 1, wherein the display means comprises a flat panel display, such as a LCD.

3. An assembly according to claim 1 or 2, wherein the carrier comprises a PCB.

4. An assembly according to any of claims 1-3, wherein the piston rod comprises an essentially non-bendable rod comprising a toothed region adapted to mesh with one or more of the rotatably mounted drive elements so as to perform a translational movement in response to a rotational movement of a rotatably mounted drive element.

5. An assembly according to any of claims 1-3, wherein the piston rod comprises a plurality of elements, said plurality of elements being displaceable or rotatably mounted relative to each other and being arranged in a manner to that the effective length of the piston rod is adjustable by displacing at least two elements relative to each other.

6. An assembly according to any of the preceding claims, further comprising sensor means adapted to provide a measure for an expelled and/or set dose of medicament.

7. An assembly according to claim 6, wherein the sensor means comprises an encoder arranged on the carrier, the encoder being in electrical communication with the electronic control circuit.

8. An assembly according to any of the preceding claims, wherein the sandwich construction comprising the display means, the carrier and the mechanical drive mechanism has a total height smaller than 25 mm, such as smaller than 20 mm, such as smaller than 15 mm, such as smaller that 10 mm.

9. A pen-like medication delivery device comprising an assembly according to any of the preceding claims.

10. A pen-like medication delivery device according to claim 9, further comprising a housing extending in an axial direction of the medication delivery device, the housing having, in cross-sectional planes perpendicular to the axial direction, a non-circular outer surface profile.

11. A pen-like medication delivery device according to claim 10, wherein the housing further comprises an opening arranged in a substantially plane surface part of the housing, the opening being adapted to be aligned with the display means of the assembly.