CN105641782A - Medical injector with ratchet-type plunger - Google Patents

Abstract

The invention discloses a medical injector. The medical injector comprises a body and a plunger. The body comprises the far end and the near end, and the plunger is moveably arranged in the body. The plunger comprises a plurality of ratchet teeth arranged at intervals in the length direction. Plugs are selectively moved by the plunger to distribute medicaments from the medical injector. The medical injector also comprises graduators, an actuator and a rotating part, wherein the graduators are arranged in the body and are used for being jointed with the plunger to allow the plunger to move towards the far side and basically prevent the plunger from moving towards the near side; the actuator comprises jointing parts to be jointed with the plunger to allow the actuator to move towards the near side relative to the plunger and basically prevent the actuator from moving towards the far side relative to the plunger; the rotating part is used for moving the jointing parts towards the near side relative to the plunger and the body.

Description

There is the medical injector of ratchet-type plunger

The divisional application of application for a patent for invention that the present invention is international filing date to be on March 17th, 2011, international application no be PCT/US2011/000493, China national application number are 201180070446.6, denomination of invention is " medical injector with ratchet-type plunger ".

Technical field

The present invention relates to packaged type medical injector plunger, it is more particularly related to ratchet-type medical injector plunger.

Background technology

Medical injector is known in the art, and these medical injectors include syringe and pen type infusion appliance. Medical injector typically comprises plunger, this plunger during injecting when delivery of medicaments for making one or more stopper advance. Although it is known in the art that syringe plunger is provided with tooth or further feature, to prevent retraction after initial injection and to re-use, syringe plunger activated typically via directly applying of straight line force. Dosage size is the direct function of plunger displacement. It is controlled by would is that difficulty to the straight-line displacement of plunger, thus results in the size being difficult to control to dosage.

About pen type infusion appliance, it is provided with leading screw or rotary type plunger, this leading screw or rotary type plunger and is mechanically coupled on dosage setting button or other actuator by a series of mechanical connections. Typical pen type infusion appliance mechanism is considerably complicated, and includes multiple part matched. In order to save cost and be prone to use, desirably, the quantity of working part is minimized.

Summary of the invention

Correspondingly, it is an aspect of the invention to provide a kind of plunger for medical injector, it is possible to make this plunger controllably advance with the part matched of minimum number.

Above-mentioned and/or the other side of the present invention is also by providing a kind of medical injector to realize, and this medical injector includes body and plunger, and this body has distal end and proximal end, and this plunger is movably disposed within body. Plunger includes the multiple spaced apart ratchet arranged along its length. The selectively moved stopper of plunger, to distribute medicament from described medical injector. Medical injector also includes: indexer, be arranged in internal, in order to engagement pistons, to allow that plunger distad moves and substantially prevents plunger proximad from moving; Actuator, has bonding part, allows that with engagement pistons actuator moves relative to plunger proximad and substantially prevents actuator from distad moving relative to plunger;And rotatable parts, it is used for making bonding part proximad move relative to plunger and body. When actuator is moved proximally to SBR relative to body, one or more ratchet crosses bonding part, so that actuator moves relative to plunger proximad. When actuator distad moves from SBR relative to body, actuator engages one or more ratchet, makes plunger distad move relative to indexer, so that stopper distad moves and distributes medicament from medical injector.

Above-mentioned and/or the other side of the present invention is also by providing a kind of medical injector to realize, and this medical injector includes body and plunger, and this body has distal end and proximal end, and this plunger is movably disposed within body. Plunger includes the multiple spaced apart ratchet arranged along its length. The selectively moved stopper of plunger, to distribute medicament from medical injector. Medical injector also includes indexer, this indexer be arranged in internal, in order to engagement pistons, to allow that plunger distad moves and substantially prevents plunger proximad from moving. Medical injector comprises additionally in actuating device, this actuating device is used for activating medical equipment, activating device and have engagement device, this engagement device is used for engagement pistons, to allow that actuating device moves relative to plunger proximad and substantially prevents actuating device from distad moving relative to plunger. Additionally, medical injector includes tumbler, this tumbler is used for making engagement device proximad move relative to plunger and body. When activating device and being moved proximally to SBR relative to body, one or more ratchet crosses engagement device, moves so that activating device relative to plunger proximad. When activating device and distad moving from SBR relative to body, activate one or more ratchet of means for engaging, make plunger distad move relative to indexer, so that stopper distad moves and distributes medicament from medical injector.

Above-mentioned and/or the other side of the present invention is also by providing a kind of method from medical injector injection medicament to realize, and this medical injector has body, and this body has distally and proximally end. The method includes following operation: allows plunger distad moving relative to body, and substantially prevents plunger from moving relative to body proximad; And allow that actuator moves relative to plunger proximad and substantially prevents actuator from distad moving relative to plunger. The method also includes following operation: is rotated by rotatable parts, so that actuator is moved proximally to SBR relative to body, thus makes actuator move relative to plunger proximad; And actuator is distad moved from SBR relative to body, thus engagement pistons, and make plunger distad move relative to body, and distribute medicament from medical injector.

Other and/or the other side of the present invention and advantage will partly describe in the de-scription, and will be partly more obvious by reading detailed description, or can be understood by the present invention puts into practice.

Accompanying drawing explanation

By connection with figures carry out detailed further below, above and/or other aspect of each embodiment of the present invention and advantage will be more obvious and be more prone to cognitive, in the drawings:

Fig. 1 is the axonometric chart of the medical injector according to one embodiment of the present of invention;

Fig. 2 is the axonometric chart of the plunger of the syringe use being available for Fig. 1;

Fig. 3 is along the line 3-3 of Fig. 2 partial cross sectional view obtained;

Fig. 4-6 is body portion sectional view, it is shown that the operation of the medical injector of Fig. 1;

Fig. 7 and 8 are axonometric charts, respectively illustrate and are available for two kinds of rocking bars that the syringe of Fig. 1 uses;

Fig. 9-11 is body portion sectional view, it is shown that use the operation of the medical injector according to one embodiment of the present of invention of the rocking bar of Fig. 7;

Figure 12 and 13 are body portion sectional views, it is shown that according to the use of the multi link formula rocking bar of one embodiment of the present of invention;

Figure 14 is available for the dose counter that one embodiment of the present of invention uses;

Figure 15 is the partial perspective view of the pivotable formula actuator of the plunger use being available for Fig. 2;

Figure 16 and 17 are body portion sectional views, it is shown that the use of the pivotable formula actuator of Figure 15;

Figure 18 is the sectional view of the medical injector according to another embodiment of the present invention;

Figure 19 is the axonometric chart of an embodiment of the Part II of the actuator of the medical injector of Figure 18;

Figure 20 is the phantom of the medical injector of Figure 18;

Figure 21 and 22 illustrate some optional embodiments of the groove of the Part II of Figure 19;

Figure 23 is the axonometric chart of another embodiment of the Part II of the actuator of the medical injector of Figure 18;

Figure 24 is the axonometric chart of the body of the medical injector of Figure 18;

Figure 25 is the axonometric chart of another embodiment of the Part II of the actuator of the medical injector of Figure 18;

Figure 26 is the partial perspective view of the medical injector of Figure 18, and this medical injector has the Part II of Figure 25;

Figure 27 illustrates another embodiment of the groove of the Part II of Figure 19;

Figure 28 is the axonometric chart of the medical injector according to another embodiment of the present invention;

Figure 29 is the axonometric chart of an embodiment of the actuator of the medical injector of Figure 28 and rocking bar;

Figure 30 and 31 are the axonometric charts of the body of the medical injector of Figure 28;

Figure 32 and 33 are the axonometric charts of the knob of the medical injector of Figure 28; And

Figure 34 is the phantom of restriction rib, and this restriction rib is used for preventing dosage setting value from exceeding available amount.

Detailed description of the invention

Now with detailed reference to each embodiment of the present invention, the example of these embodiments is shown in the drawings, and wherein, corresponding accompanying drawing labelling refers to corresponding element from start to finish. The present invention is illustrated by the embodiments described herein by referring to accompanying drawing, rather than the present invention is any limitation as. As will be understood by those skilled in the art, such as the term of upper and lower, bottom and top etc is relative property, in order to contribute to explaination, rather than restrictive.

With reference to accompanying drawing, illustrated therein is medical injector 10, this medical injector 10 is provided with the plunger 12 that can add ratchet. As the skilled person will recognize, medical injector 10 can have various forms, including syringe or pen type infusion appliance. According to embodiments of the invention, medical injector 10 is particularly well-suited for using at least one fixed dosage, and even better is suitable to use a series of fixed dosage. Medical injector 10 can construct in any known manner, to adapt with plunger 12 as described herein. Medical injector 10 can include the reservoir 14 for holding injectable medicament, and this reservoir 14 can be medicine canister, or this reservoir 14 can be formed directly in medical injector 10. Reservoir 14 can have one or more stopper associated there, as known in the art.Medical injector 10 can also be provided with the pin 18 for injecting, and this pin 18 can removably link or be attached on medical injector 10, for instance forms " column " and arranges.

Plunger 12 is elongated, and is general flat. Multiple spaced apart ratchets 20 are arranged along the length of plunger 12. In one is preferably arranged, plunger 12 includes plate shape body 22, and this plate shape body 22 has the first relative front and the second front 24,26. Ratchet 20 is arranged on the first front 24, and in another kind is preferably arranged, also is disposed on the second front 26. Preferably, the ratchet 20 on the first front and the second front 24,26 is axially directed at along the length of plunger 12.

Ratchet 20 is configured so that plunger 12 can carry out one-way movement. Specifically, with reference to Fig. 3, ratchet 20 is preferably zigzag, has inclined surface 28 and shoulder stopper section 30. As it is shown on figure 3, the inclined surface 28 of the ratchet 20 on the first front and the second front 24,26 is oriented, facing on identical general direction. Shoulder stopper section 30 preferably extends transversely with from the first front and the second front 24,26 by being oriented substantially vertically.

Plunger 12 can also have one or more guide rail 27 extended from the first front 24 and/or the second front 26. Guide rail 27 can be formed as, and is passed through the notch matched of one or more correspondingly-shaped of formation in medical injector 10 and slides. Guide rail 27 can provide stability during use, particularly during the translation of plunger 12.

With reference to Fig. 4-6, plunger 12 is arranged in the body 32 of medical injector 10. Body 32 includes distal end 34 and proximal end 36, and this distal end 34 is arranged to sensing patient during injecting, and this proximal end 36 is arranged to during injecting away from patient (Fig. 1). During use, medical injector 10 is configured so that plunger 12 can uniaxially move wherein in the distal direction towards distal end 34, but can not move in the proximal direction of proximally facing end 36. In order to be conducive to such one-way movement, being provided with at least one indexer 38, this indexer 38 is formed as in order to engagement pistons 12. Indexer 38 is configured so that plunger 12 can towards distal end 34 distal motion of body 32, but can not towards proximal end 36 proximal motion of body 32.

Indexer 38 includes deflection pawl 40, and this deflection pawl 40 is as schematically illustrated in figure 3, including inclined abutment surface 42 and the stop surfaces 44 faced out. Indexer 38 can flex outward, to allow that composition surface 42 rises along the inclined surface 28 of each ratchet 20 when plunger 12 is relative to its distal motion. When distal motion during sufficient amount, ratchet 12 crossed by indexer 38, and under the intrinsic elasticity of indexer 38, snap inward, thus stop surfaces 44 is directed at shoulder stopper section 30. Preferably, stop surfaces 44 is formed as generally parallel with shoulder stopper section 30. When (proximad) moves plunger 12 backward, shoulder stopper section 30 and stop surfaces 44 engage interferingly, thus prevent plunger 12 proximal motion. In a preferred embodiment, being provided with a pair indexer 38, working thus abutting against the ratchet 20 being arranged on both the first front and the second front 24,26, as Figure 4-Figure 6. It may further be preferable that be provided with a pair indexer 38, this is axially aligned to indexer 38, thus will provide for the clamping effect of plunger 12.This clamping effect can provide stable retentivity for plunger 12.

Indexer 38 can be formed as, and by means of intrinsic elasticity, such as the selection (such as, thermoplastic formed) by means of material, and has flexibility. It addition, or selectively, indexer 38 can include suspension arm 46, and this suspension arm 46 makes the pawl 40 being connected to bend. Indexer 38 is formed as, and has natural, unbiased state as Figure 4-Figure 6, and wherein, indexer 38 is positioned to work in order to the shoulder stopper section 30 against ratchet 20. Suspension arm 46 is formed with enough memory internals, to provide the non-bias state for indexer 38.

Medical injector 10 also includes actuator 48, and this actuator 48 has bonding part 50, and this bonding part 50 is in order to engage one or more ratchet 20. Bonding part 50 preferably includes engaging claw 52, and this engaging claw 52 has inclined abutment surface 54 and the stop surfaces 56 faced out, similar with the structure of pawl 40 described above. Preferably, being provided with two bonding parts 50, the two bonding part 50 is arranged on the first front and the second front 24,26.

With reference to Fig. 4, plunger 12 is positioned to engage in each stopper 16. In order to cause the actuating of medical injector 10, as it is shown in figure 5, actuator 48 moves to SBR, make bonding part 50 proximal motion. Indexer 38 prevents plunger 12 proximal motion, hence allows to actuator 48 relative to plunger 12 proximal motion. When plunger 12 remain stationary and bonding part 50 relative to plunger 12 proximal motion, one or more ratchet 20 is crossed in bonding part 50. Actuator 48 is moved fully, to reach SBR.

For the actuating of medical injector 10, actuator 48 is made to move from SBR so that bonding part 50 distal motion. Bonding part 50 engages one or more ratchet 20, is especially for use in the interference engagement between shoulder stopper section 30 and stop surfaces 56. Specifically, bonding part 50 engages contiguous distally ratchet 20. The distal motion of bonding part 50 makes plunger 12 with its distal motion. The distal motion of plunger 12 causes that again stopper 16 is distally advanced so that an implantation dosage is applied. Ratchet 20 can cross indexer 38 in a distal direction.

Until by medical injector 10 applied dose size be the interval between ratchet 20 and/or when actuator 48 moves to SBR bonding part 50 relative to the function of the proximad amount of movement of ratchet 20. In order to produce fixed dosage, one or more key 58 can be limited on medical injector 10 and/or actuator 48, one or more key 58 are formed as being nested in respective channel 60, and sliding along respective channel 60, these respective channel 60 are formed in medical injector 10 and/or actuator 48. As Figure 4-Figure 6, it is preferred that key 58 is formed on actuator 48, and passage 60 formed in medical injector 10. With reference to Fig. 4, key 58 before the use, at the distal end place of passage 60. When actuator 48 proximad moves, key 58 is proximally advanced the recent side position corresponding with the SBR of actuator 48 in passage 60. The range of movement of the length limitation actuator 48 of the key 58 stroke in passage 60 can by medical injector 10 applied dose size to limit. As it can be seen in figures 5 and 6, key 58 is distally advanced into farthest side position with actuator 48 during use.

Actuator 48 shown in figs. 4-6 is rectilinearly-moved slide type actuator, and power is applied directly on plunger 12 by this rectilinearly-moved slide type actuator. As the skilled person will recognize, actuator 48 can have various structure. With reference to Fig. 7-8, actuator 48 can include being pivotally mounted to rocking bar 62 thereon. Rocking bar 62 is framework shape, has first end 64 and the second opposed end 66, and this first end 64 is used for being pivotably mounted on actuator 48, and this second opposed end 66 is used for being pivotably mounted on medical injector 10. Bonding part 50 is arranged between first end and the second end 64,66. As shown in FIG. 7 and 8, it is possible to be provided with two bonding parts 50, with ratchet 20 combined effect on the first front and the second front 24,26.

Noting, the interval impact between first end and the second end 64,66 is transmitted from actuator 48 to the power of plunger 12, particularly produces torque. Interval L between first end and the second end 64,66 and bonding part 50, from interval S1, S2 of first end and the second end 64,66, affect how torque produces and be delivered to plunger 12.

With reference to Fig. 9, it is shown that actuator 48 before initial use under state, rocking bar 62 distad tilts. With reference to Figure 10, actuator 48 has progressed to SBR, and rocking bar 62 pulls by means of the proximad of the rotation around the second end 66, thus tilting in a proximal direction. During this motion, bonding part 50 is pressed and same way described above, crosses one or more ratchet 20. As shown in figure 11, actuator 48 moves from SBR, to cause the actuating of medical injector 10. Leave the movement of SBR by means of actuator 48, make rocking bar 62 be distally advanced around the second end 66 so that bonding part 50 also leads to plunger 12 and is distally advanced. Dosage size can be arranged by key 58/ passage 60 described above and/or both range of movement of rocking bar 62 limit.

As the skilled person will recognize, rocking bar 62 can be directly coupled on actuator 48, as shown in figs. 9-11. As the skilled person will recognize, multi link is arranged and be can be used to be connected on actuator 48 rocking bar 62. With reference to Figure 12 and 13, one or more connecting rod 68 can be connected between rocking bar 62 and actuator 48, to provide for its power moved. Connecting rod 68 can utilize any arrangement that power can be delivered to rocking bar 62 from actuator 48. As shown in Figures 12 and 13, utilize two connecting rods 68 (68A, 68B), make connecting rod 68A be pivotably connected on actuator 48 and be pivotably connected on connecting rod 68B, and make connecting rod 68B be pivotably connected on connecting rod 68A and be pivotably connected on rocking bar 62. Connecting rod 68A, 68B transfer force to rocking bar 62 synergistically.

With reference to Figure 15-17, actuator 48 can be arranged to are nonlinearly move. As seen in figs. 15-17, actuator 48 can be formed as can pivoting around fulcrum 70. When actuator 48 is pivoted out from medical injector 10 around fulcrum 70, bonding part 50 proximad is made to move. On the contrary, actuator 48 is around the inside pivot of fulcrum 70 so that bonding part 50 is distad moved. Bonding part 50 is pressed and same way described above and plunger 12 combined effect.

With reference to Figure 15 and 16, it is shown that medical injector 10 state before use under. In order to facilitate the manipulation of actuator 48, it is provided that grasping ring or pad 72, this grasping ring or pad 72 extend radially outwardly from medical injector 10, to be conducive to the movement of actuator 48.In order to prepare to use, as, shown in arrow in figure 16, made actuator 48 be pivoted to SBR, as shown in figure 17. In order to cause the actuating of medical injector 10, actuator 48 is made inwardly to pivot from SBR, as shown in arrow in fig. 17.

The size of dosage can be fixed by restricting the slewing area of actuator 48 with pivotable actuator 48. A part 74 for medical injector 10 can be configured to rotation (the being particularly turned out) scope in order to limiting actuator 48, and such restriction scope is corresponding with SBR.

Actuator 48 can be formed as linear slide actuator, but is constructed to be permeable to accept nonlinear force, so that actuator 48 is adjusted SBR. With reference to Figure 18-27, actuator 48 can include Part I 48A, and this Part I 48A as described above is formed. It addition, actuator 48 can include rotating Part II 48B, this rotating Part II 48B is connected on Part I 48A such that it is able to rotate relative to it. This layout allows that actuator 48 is rotated adjusting SBR. Rotate the feature adjusting pen type infusion appliance typically, and be probably preferred for some user.

Part II 48B can be accessible from the outside of medical injector 10 such that it is able to by user from outer side engagement; Specifically, Part II 48B extends from proximal end 36 proximad of body 32. Part I and Part II 48A, 48B are rotatably coupled in any known manner. As limiting examples, Part II 48B could be formed with continuous loop 80, and this continuous loop 80 rests upon in the passage 82 of Part I 48A. The size and dimension of ring 80 is configured to be freely rotatable in passage 82, make Part I be axially fixed with Part II 48A, 48B thus together with move. As the skilled person will recognize, ring 80 and passage 82 can reverse arrangement on Part I and Part II 48A, 48B.

As shown in figure 19, groove 84 is around the outside formation of Part II 48B. One or more key 86 is arranged on peripheral part of medical injector 10, for instance be arranged on the body 32 of Part II 48B, and the positions and dimensions of one or more key 86 is set to be sitting in groove 84 such that it is able to move along its length. The length of groove 84 defines the degree of rotation of Part II 48B. According to an embodiment, groove 84 is spiral at least partially, thus having helix shape. As persons skilled in the art will recognize, one or more key 86 can be arranged on the outside of Part II 48B, and the groove 84 of correspondence can be formed on peripheral part of medical injector 10.

Part II 48B rotation in the first rotation direction causes that Part I and Part II 48A, 48B proximad move so that bonding part 50 is moved proximally to SBR accordingly. Specifically, the rotation of Part II 48B causes that its proximad moves, and as one man causes that Part I 48A and bonding part 50 proximad move. Part I 48A proximad non-rotatingly moves. The degree of rotation of the length limitation Part II 48B of groove 84, thus restriction can applied dose. Once turn to setting dosage, by press Part II 48B just can application dosage, this causes that Part II 48B is distally advanced, and correspondingly results in Part I 48 and be distally advanced non-rotatingly together with bonding part 50.

About being distally advanced of Part II 48B, it is preferred that Part II 48B advances point-blank without rotation. For this reason, it is preferred that, groove 84 is formed with the first spiral section 84a and the second axial component 84b, and this second axial component 84b extends from the first spiral section 84a, generally parallel with the longitudinal axis of Part II 48B. With reference to Figure 21, about this layout, one or more key 86 passes the first spiral section 84a in a proximal direction by means of the rotation of Part II 48B. Elbow curved 88 is limited to the first spiral section 84a and the joint of the second axial component 84b, this elbow curved 88 restriction degree of rotation, and thus restriction Part II 48B proximad move. Elbow curved 88 limits the ready position of actuator 48. In order to activate, Part II 48B is pressed, and is caused is distally advanced without rotation point-blank when one or more key 86 is through the second axial component 84b. This causes being distally advanced of Part I 48A and being distally advanced of plunger 12 further through the joint with bonding part 50. The rectilinear movement of Part II 48B allows that be applied on it power fully transmits on an axial direction, without resolving into two or more components. So, being applied on Part II 48B whole actuating power is all delivered to actuator 48.

Single dosage pattern for this layout, it is possible to use the first spiral section and second axial component 84a, 84b composition single group. For multiple dosage, as shown in figure 22, groove 84 can extend into, and auxiliary screw shape part 84a ' can directly extend from the end of the second axial component 84b, and it extends in auxiliary axial component 84b ', and the rest may be inferred according to actual needs, and ground is arranged. Can limit continuously around Part II 48B according to the series that an embodiment, the first spiral section 84a and the second axial component 84b are formed, to advantageously form multiple dosage. According to an embodiment, corresponding group about one or more key 86 can utilize more than one groove 84. And, one or more groove in each groove 84 and one or more key in each key 86 can be arranged on Part II 48B and/or peripheral part of medical injector 10.

Preferably, it should avoid Part II 48B along rotating backward. For this, as shown in figs. 23-24, one or more ratchet 90 can be formed on Part II 48B, it is formed as in order to one or more placed channel 92 of engagement in snap engagement, one or more placed channel 92 are formed on medical injector 10 around Part II 48B, as formed on body 32. Preferably, placed channel 92 be arranged to Part II 48B in ready position corresponding, and such a ready position placed channel 92 is elongated, thus ratchet 90 can to use period with Part II 48B at dosage along its length mobile. As the skilled person will recognize, ratchet 90 (one or more) can be formed on medical injector 10, and placed channel can be formed on Part II 48B.

It addition, along the reverse axially-movable of the second axial component 84b, particularly after injection, be undesirably. For this, as shown in figs. 25 and 26, locking tab 94 is arranged on Part II 48B, this locking tab 94 is configured in order to terminate position (such as, arriving, with at one or more key 86 of the end of dose stroke, the position that the end of the second axial component 84b coincides) place's engagement in snap engagement of coinciding in locking channel 96 with injection.The axially-movable of Part II 48B thus be restricted. Locking channel 96 can be configured to, and the rotation by means of Part II 48B allows that locking tab 94 rotates to separate with locking channel 96, for preparing with post dose. Locking channel 96 is formed on peripheral part of medical injector 10, as formed on body 32. As the skilled person will recognize, locking tab 94 can be formed on medical injector 10, and locking channel 96 can be arranged on Part II 48B.

Additionally, as the skilled person will recognize, by means of layout mentioned above, particularly by means of the use of the Part I of groove 84 and Part II 84a, 84b, dosage is fixed dosage. According to the embodiment allowing variable dose, it is distally advanced period at Part II 48B, it is possible to allowing Part II 48B to rotate, simultaneously one or more key 86 is advanced along groove 84. Thus, in this embodiment, as shown in figure 27, it is only necessary to the spiral section 84a of groove 84 is provided. About this layout, Part II 48B can turn to any position along groove 84 (84a), to set dosage by means of what allow dosage along rotating backward of groove 84 (84a). Scale known in the art or other mark can be arranged to corresponding with the rotation displacement of Part II 48B, to provide the instruction setting dose value (doseamount). In order to limit rotating backward undesirably, and in order to be maintained at the position setting dosage place, it is possible to use releasable holding means, as known in the art.

Part I utilizes together with any one feature in each feature described herein with Part II 48A, 48B. Preferably, Part I and Part II 48A, 48B and rocking bar 62 are used along.

Figure 28 is the axonometric chart of the medical injector 10 according to another embodiment of the present invention. With reference to Figure 28-33, medical injector 10 includes body 32, knob 100, actuator 48 and cap 101, and this knob 100 is pivotally connected on body 32, and this actuator 48 is arranged in body 32, and this cap 101 is connected on actuator 48. As shown in figure 29, actuator 48 includes groove 84, as described above. Actuator 48 also includes axial notch 102. Axial notch 102 and axial bond 104 interact (figure 30 illustrates), and this axial bond 104 is arranged on the inside of body 32, to guide the axially-movable of actuator 48 relative to body 32, and prevents the actuator 48 rotation relative to body 32. As the skilled person will recognize, axial notch 102 can be arranged on the inside of body 32, and axial bond 104 can be arranged on actuator 48, without deviating from the scope of the present invention.

As shown in figure 31, body 32 also includes the circumferential groove 106 being arranged in its proximal end place, for being connected with knob 100, as described in more detail hereinbelow. It addition, as described in more detail hereinbelow, body 32 includes suspension, circumference arm 120, and this arm 120 has denation 122, and this denation 122 is arranged in the end of arm 120, and projects radially outwardly.

Figure 32 is the axonometric chart of the distal end of knob 100, and Figure 33 is the axonometric chart of the proximal end of knob 100. As shown in figure 32, the adapter 108 that knob 100 includes circumferentially and projects radially inward.According to an embodiment, adapter 108 is approximate wedge shape. For assembling medical infusion appliance 10, knob 100 is distad inserted in the proximal end of body 32, until adapter 108 slides in the circumferential groove 106 of body 32, knob 100 is connected on body 32 by this. Knob 100 is fixed on body 32 by the wedge-type shape of adapter 108, substantially prevents knob 100 from moving relative to body 32 proximad, allows that knob 100 rotates relative to body 32 simultaneously.

As shown in figure 32, adapter 108 is arranged in the diameter portion 110 of knob 100. Also being disposed in the diameter portion 110 of knob 100 is triangular groove 112. Triangular groove 112 interacts with the denation 122 on arm 120, to allow that knob 100 uniaxially rotates relative to body 32. That is, triangular groove 112 and denation 122 interact, to allow that knob 100 rotates only along the direction making plunger 12 be proximally advanced. Knob 100 also has reduction diameter portion 114, after this reduction diameter portion 114 is connected between adapter 108 with circumferential groove 106, it is prevented that knob moves relative to body proximad. It addition, cam shape projection or key 116 project radially inward from reducing diameter portion 114. Being similar to key 86 described above, the groove 84 of key 116 and actuator 48 interacts, and converts the proximad axially-movable of actuator 48 to the rotational motion by knob 100. After actuator 48 proximad axially-movable, user pressing cap 101 (being connected on actuator 48), distad to move actuator 48 relative to body 32, and thus make plunger 12 be distally advanced.

With reference to Figure 33, knob 100 also includes the rib 118 radially highlighted at its proximal end place. Rib 118 plays the effect at user interface, in order to allow user hold and to rotate knob 100.

As the skilled person will recognize, it is possible to use there is the medical injector 10 of various feature. With reference to Figure 12-14, can arranging dose counter about medical injector 10, this dose counter provides the instruction of the quantity of obtained dosage to be administered. Such as, a series of dosage indicator holes 76 can be formed in medical injector 10, specifically can from being seen outside it. In an example provided, pointer 78 can be arranged on actuator 48, and is formed as to be seen by the single hole in each dosage indicator hole 76. During use, along with plunger 12 1 dosage then dosage (dosebydose) be distally advanced, pointer 78 is same to advance along the dosage indicator hole 76 becoming series. According to an embodiment, it is positioned at the instruction of the quantity of the quantity offer doses remaining of the dosage indicator hole 76 in the distally of pointer 78. With the pointer 78 in the farthest side occurring in dosage indicator hole 76, it is provided that the instruction of " not being suitable to the doses remaining used ".

Preferably, pointer 78 is formed by the contrast color being positioned at the part near dosage indicator hole 76 relative to medical injector 10, thus the traverse easily visible pointer 78 of dosage indicator hole 76.

Additionally, according to an embodiment shown in Figure 34, prominent restriction rib 98 can extend from the distal part of plunger 12, and this prominent restriction rib 98 is arranged to arrange with the dosage on plunger 12 coincide, and this dosage arranges corresponding with the last available medication amount in reservoir 14. Correspondingly, about the predetermined extent being distally advanced of plunger 12, restriction rib 98 is formed as engaging interferingly a part for actuator 48, and stops by its proximal motion.In such a way, the dosage that actuator 48 sets can not more than the available quantity in reservoir 14.

While there has been shown and described that only several embodiments of the present invention, but the invention is not restricted to the embodiment described. On the contrary, it would be recognized by those skilled in the art that and can carry out the various changes without departing from principles of the invention and spirit for these embodiments, the scope of the present invention is limited by claims and its equivalent.

Claims (4)

1. a medical injector, including:

Body, described body has distal end and proximal end;

Plunger, described plunger is movably disposed within described body, and described plunger has the multiple spaced apart ratchet arranged along its length, and the selectively moved stopper of described plunger, to distribute medicament from described medical injector;

Indexer, described indexer be arranged in described internal, in order to engage described plunger, to allow that described plunger distad moves and substantially prevents described plunger proximad from moving;

Actuator, described actuator has bonding part, in order to engage described plunger, described bonding part allows that described actuator moves relative to described plunger proximad and substantially prevents described actuator from distad moving relative to described plunger; And

Rotatable parts, described rotatable parts are used for making described bonding part proximad move relative to described plunger and described body;

Wherein, when actuator is moved proximally to SBR relative to described body, one or more ratchet crosses described bonding part, so that described actuator moves relative to described plunger proximad; And

Wherein, when described actuator distad moves from described SBR relative to described body, described actuator engages one or more ratchet, makes described plunger distad move relative to described indexer, so that described stopper distad moves and distributes medicament from described medical injector;

Wherein, described rotatable parts include knob, and this knob is arranged in the proximal end place of described body;

Wherein, one in the inside of described actuator and described body includes axial notch, and the another one in the inside of described actuator and described body includes the axial bond of correspondence, described axial bond is slidably received within described axial notch, to guide described actuator to be axially moveable relative to described body, and prevent the rotation relative to described body of the described actuator;

Wherein, described actuator and the one in described knob include the groove with substantially spiral section, and the another one in described actuator and described knob includes the key of correspondence, and the key of described correspondence is slidably received within described groove; And

Wherein, the rotation of described knob causes described key relative to the movement with the substantially described groove of spiral section, thus makes described actuator be axially moveable relative to described body.

2. medical injector according to claim 1, wherein, one in described knob and described body includes adapter, and the another one in described knob and described body includes the circumferential groove of correspondence, the circumferential groove of described correspondence holds described adapter rotationally, in order to described knob is pivotally connected to the proximal end of described body.

3. medical injector according to claim 1, wherein, described knob includes shaping axial notch, and described body includes suspension arm, this suspension arm has shaping projection, this shaping projection is radially projecting from the end of described suspension arm, and described shaping projection has the shape corresponding with the shape of described shaping axial notch; And

Wherein, the axial fillistered joint of described shaping closes described projection, to allow the described knob one-directional rotation relative to described body.

4. medical injector according to claim 3, wherein, described shaping axial notch and the corresponding shape shaping projection are general triangular.