Self-service injector

Abstract

A self-service injector includes a torsion spring having stored energy for administration of a liquid active substance. The invention relates to a self-service injector having a housing (1) with a holder (18, 19) for fixing an insertable syringe (3) with a barrel (4), a sealing plug (26) and a needle, the active substance of which can be discharged under the action of hydraulic pressure when activated in particular. For this purpose, the piston (6) in the cylinder (4) can be actuated by a pivot lever (7) which is articulated on a piston slide (2) sliding along a guide rail (11) in the housing (1). And the other end of the pivoting rod (7) is hinged to a pivotable leg (8) of a bias torsion spring (9). By triggering a pivoting movement of the biasing spring leg (8), the piston (6) can be slid into the needle cylinder (3) in a first pivoting phase by means of a piston slide (22), and barbs (10) on the piston slide (22) thus can be hooked on the needle cylinder (3). In a subsequent pivoting movement, the syringe (3) can be retracted into the housing (1) such that the needle disappears within the housing.

Description

Technical Field

[0001] The present invention relates to a self-injecting syringe for users to inject and administer medicine by themselves. Background Art

[0002] Almost half of all medications are now administered via syringe. This equates to approximately 50 billion syringes used worldwide each year. One-third of these are administered orally, while the rest are administered rectally or through the eyes, nose, and ears. Among the medications that are automatically injected, insulin accounts for the largest share. Self-injecting syringes used for this purpose inject liquid medications by storing energy. The market for prefilled syringes is expanding with the growing demand for such syringes, the increasing prevalence of chronic diseases, technological advances, the growing popularity of auto-injection parenteral injection devices, and the introduction of supportive government regulations (especially for needle sticks). In addition, the growing awareness of the benefits of prefilled syringes by more patients and healthcare professionals, as well as the increasing presence of biologics and biosimilars in the pharmaceutical market, are also contributing to the growth of the prefilled syringe market.

[0003] For example, WO 2011043714 A1 discloses a device for administering drugs. The device includes an elongated tubular housing having two opposite proximal ends 10 and distal ends 12. Further, it also has a needle guard 20 slidably and coaxially arranged in the housing. A syringe holder mechanism includes a syringe holder 36 slidably arranged in the needle guard. The syringe 16 includes a stopper 92, a drug and a needle, and is arranged in the syringe holder. A first actuating element 56 is slidably arranged in the housing and connected to the needle guard. A second actuating element 66 is slidably arranged in the first actuating element. In addition, there is a driving mechanism slidably arranged in the second actuating element, which is slidably arranged in the second actuating element and releasably connected to the retaining element and the second actuating element. The driving mechanism can generate a driving force to move the syringe holder mechanism in the first step to insert the needle into the injection site, and to move the stopper in the second step to discharge the drug through the needle. To this end, the drive mechanism is controlled by a first and a second actuating element. The device has as a special feature a second actuating element 66 with information means so that after complete expulsion of the drug, the remaining actuating force will move the second actuating element towards the distal end portion of the elongated tubular housing, providing the user with an audible, visual and / or tactile feedback that the injection is complete.

[0004] US1 0420 898 further discloses a drug dispensing device, which is equipped with a drive device, which acts on a drug container to inject the drug. To this end, the drug dispensing device has a retaining device for maintaining the drive device in a preloaded state. Further, the drug dispensing device has a matching actuating device to cooperate with the retaining device to release the drive device from a biased state, and the device also includes a feedback device configured to cooperate with the retaining device and the drive device to generate an auditory and / or tactile and / or visual signal indicating that the drug has been completely injected. US-A-20040054326 describes a self-service syringe, see Figures 1 to 5 , comprising a main body 21 for receiving a syringe or barrel 1, in which a stopper for injecting a dose of medication is slidably mounted, a drive mechanism, including energy storage means 10 in the form of a coil spring, for injecting a dose of medication when a trigger 14 is actuated from a cocked position, the drive mechanism comprising a rotatable crank mechanism 8 associated with a slidable drive piston 5, the coil spring acting on a rotating cam element 8. However, the force that can be applied and the force increment under the drive of the coil spring are too weak to ensure that the inserted syringe is completely emptied. Summary of the invention

[0005] In view of this prior art, the object of the present invention is to provide an improved auto-injector which has a lower manufacturing cost, a higher functional safety, achieves safe administration of liquid drugs, has fewer components and a minimum proportion of metal parts compared to traditional solutions, and is simpler and safer for the user to operate. In particular, it is designed to safely avoid injuries or infections caused by the needle of the used syringe, and to fully retract the needle of the syringe into the housing after activation so that it cannot harm or infect anyone.

[0006] The scheme provides a self-service syringe with stored energy for administering liquid active substances. The self-service syringe has a shell, a bracket for holding a syringe to be inserted, the syringe has a barrel, a sealing pin and a needle, and is used to hydraulically inject the active substance through the needle. The scheme is characterized in that: the piston can be actuated by a piston slider, and the piston slider is guided along a guide rail in the shell by a pivot rod hinged to it, and the other end of the pivot rod is hinged to a pivotable spring leg of a prestressed torsion spring with multiple coils, and the second spring leg is fixedly locked on the shell and can trigger the pivoting movement of the pivotable spring leg by releasing the prestressed torsion spring, wherein, in a first pivoting stage, the piston can be pushed into the syringe through the pivotable spring leg and the piston slider hinged at its end so that the barb on the piston slider hooks on the syringe, and then, in a subsequent pivoting stage, the piston can be pushed into the syringe through the piston slider hinged at its end.

[0007] Hereinafter, an embodiment of the auto-injector will be described in detail with reference to the accompanying drawings, and its functions will be explained. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 The autoinjector is shown with its lower housing portion, the upper housing portion removed, with all components located therein, a push cap on the needle, and an associated puller for pulling the push cap off;

[0009] Figure 2 The self-injector and all its internal parts are shown, the push cover on the needle has been pulled open, and the drive device is in a state ready for injection;

[0010] Figure 3 Shows Figure 2 a rear view of the auto-injector shown;

[0011] Figure 4 The autoinjector and all its internal components are shown with the piston slightly retracted into the barrel of the syringe shortly after the injection is initiated;

[0012] Figure 5 Shows Figure 4 a rear view of the auto-injector shown;

[0013] Figure 6 The autoinjector is shown with the piston approximately halfway through its stroke, during an injection;

[0014] Figure 7 Shows Figure 6 a rear view of the auto-injector shown;

[0015] Figure 8 The autoinjector is shown during an injection process, with the piston having travelled approximately two thirds of its stroke to inject the active substance;

[0016] Fig. 9 Shows Figure 8 a rear view of the auto-injector shown;

[0017] Fig.10 The autoinjector is shown in the process of injecting an active ingredient after the piston has traveled almost its full stroke;

[0018] Fig.11 Shows Fig.10 a rear view of the auto-injector shown;

[0019] Fig.12 The autoinjector is shown in the final stage of forward movement of the piston;

[0020] Fig.13 Shows Fig.12 a rear view of the auto-injector shown;

[0021] Fig.14The autoinjector is shown at the end of the forward movement of the piston, with the barb hooked over the barrel to allow for the retraction of the barrel during the subsequent injection phase;

[0022] Fig.15 Shows Fig.14 a rear view of the auto-injector shown;

[0023] Fig.16 The autoinjector at the end of the injection is shown;

[0024] Fig.17 Shows Fig.16 a rear view of the auto-injector shown;

[0025] Fig.18 The auto-injector is shown in the initial stages of retracting the syringe;

[0026] Fig.19 Shows Fig.18 a rear view of the auto-injector shown;

[0027] Fig. 20 An auto-injector is shown with the syringe and its needle fully retracted into the housing;

[0028] Fig.21 Shows Fig. 20 a rear view of the auto-injector shown;

[0029] Fig. 22 The auto-injector is shown after the housing is closed;

[0030] Fig.23 Shows Fig. 22 The self-service syringe shown has its top shell opened and is in an initial state ready to be used;

[0031] Fig.24 Shows the details of the automatic syringe locking mechanism, relative Fig.23 The position shown is rotated 180° about the longitudinal axis, and the interior of the upper part of the housing can be seen, and the enlarged view is shown in the circle on the right;

[0032] Fig.25 Shows Fig. 22 An enlarged cross section of the top of the housing is shown, with a hole opened in the housing to expose the internal structure;

[0033] Fig.26 A view of the opening shown at 25 is shown, again enlarged to clearly see the components visible inside;

[0034] Fig. 27 The autoinjector is shown in its initial position, the release slide and its displacer acting as a trigger for the latch;

[0035] Fig.28 Shows Fig. 27 The autoinjector shown, shortly after being triggered;

[0036] Fig.29 Shows Fig. 27 The autoinjector is shown with the spring leg having traveled approximately halfway;

[0037] Fig.30 Shows Fig. 27 The auto-injector shown has the syringe beginning to retract;

[0038] Fig.31 Shows Fig. 27 In the auto-injector shown, the spring leg has traveled approximately 2 / 3 of the way;

[0039] Fig.32 Shows Fig. 27 In the auto-injector shown, the spring leg has traveled approximately 3 / 4 of the way;

[0040] Fig.33 Shows Fig. 27 In the auto-injector shown, the spring leg has traveled its full stroke;

[0041] Fig.34 The two housing parts of the autoinjector are shown snapped together to show the release mechanism with the latch displacer;

[0042] Fig.35 Shown is a fixing plate for placing the autoinjector on top for assembly. DETAILED DESCRIPTION

[0043] Figure 1The autoinjector and its lower housing part 1 are shown, the upper housing part has been removed, all the components are located therein, and there is a push cap 27 on the needle, so that the needle is not visible in this figure. All parts or components of the autoinjector are identified and described below. The rear housing part H contains the entire drive mechanism of the autoinjector. The rear part of the housing 1 is a bolt 16 in the form of a hollow cylinder molded by plastic injection, on which a torsion spring 9 is mounted. The axis 15 of the torsion spring 9 is marked and is perpendicular to the bottom of the housing. One spring leg 17 of the torsion spring 9 is fixedly mounted, which is in contact with the housing 1 and is fixed in a correspondingly shaped retainer 24 for this purpose. The other spring leg 8 is movable, and its outer end is connected to the rear end of the pivot rod 7 through the knee joint 2. The movable spring leg 8 can be pivoted clockwise from the starting position shown in the figure by the torsion spring 9 until it hits the limit cam 25. Therefore, it also rotates the pivot rod 7 from the starting position shown in the figure relative to the longitudinal axis of the housing 1 to a roughly symmetrical opposite position. At the same time, the pivot rod 7 pushes the piston slider 22 connected to it by the joint 28 from the back to the front (i.e. in the direction of the syringe 3), until the pivot rod 7 runs in the same direction as the piston slider 22, and with further pivoting, pulls the piston slider 22 slightly backward until the movable spring leg 8 hits the limit cam 25. Before use, the needle of the syringe protrudes from the front of the housing 1 and is protected by a rubber or plastic push cover 27, so that the needle is not visible in the figure. The needle is completely surrounded by a cubic or rectangular protective cavity 35 with a hole 37 at the front, so that the protective cavity is only visible from Fig. 22 The bottom of the figure shows the first part of the automatic syringe. It protects the needle on the one hand and is used to trigger the automatic syringe on the other hand, which will be explained clearly later. A puller 46 is also shown at the bottom. This puller 46 for the push cover 27 is arranged on the push cover 27 and is located above the protective cavity 35. The protective cavity is a plastic hollow body that is roughly cubic or rectangular, with an open side, and a metal tube section 47 with a plurality of inwardly protruding barbs 48 protruding from the opening. The puller 46 drives its tube section 47 to slide through the push cover 27 from the front end so that the automatic syringe is pushed together with the syringe equipped with the cubic puller 46, and when pushed into place, it is directly connected to the protective cavity 35 not shown in this figure. Therefore, the housing ends at the front with the cubic or rectangular closed end, that is, with the puller 46. When using the syringe 3, the user only needs to pull the puller 46 away from the housing 1 to remove the push cover 27, and its barbs 48 steadily pull the push cover 27 off the needle. But even at this time, the needle is still protected in the protection cavity 35 with a hole 37 at the front. The protection cavity 35 is a part of the release mechanism, such as Fig. 22 As shown. The user can press the hole 37 of the protective cavity 35 directly on the body where the injection is required. When the auto-injector is pressed against the skin, the protective cavity 35 is pushed into the housing 1 a short distance to trigger the injection. Then, the active ingredient is automatically injected, and the needle immediately and automatically retracts into the housing 1, so that the needle disappears completely and will no longer harm or infect anyone.

[0044] The piston slide 22 is integrally formed at the front end in the form of a piston 6, which extends into the open end of the barrel 4 of the syringe 3 and is inserted into the front housing part V. The piston slide 22 is arranged along a guide rail 11 forming a groove and is guided on the housing 1 so that it can move longitudinally. The syringe 3 is placed on a bracket of the housing 1, which is in the form of two U-shaped rods 18, 19, whose shape matches the syringe 3 and its barrel 4. A sealing pin 26 can be seen at the front of the piston 6, which is located inside the barrel 4 and can be pushed forward in a sealed manner for hydraulic injection of the contents of the syringe from the front of the needle. The piston slide 22 is formed with an elastic barb 10, and its lower side has a push-in bevel 12, through which it can move on the rear end 13 of the syringe 3 and then hook on the flange 14 of the syringe 3 so as to pull it back into the housing 1 after the injection is completed. However, in order to prevent the syringe 3 from being pushed backward into the housing 1 when the needle is inserted, a stopper 20 for the flange 14 is formed in the housing base 1. At the rear, a slope 21 that is inclined downward in the rear direction or inclined upward in the front direction is provided near the stopper 20. If the piston slide 22 moves forward, its lower edge (also forming a slope that is not visible in the figure) moves onto the slope 21 at the end and presses the elastic leg 29 downward, whereby the stopper 20 releases the flange 14, so that the syringe 3 can be pulled into the housing without being hindered by the barb 10.

[0045] The functions of the automatic syringe are described and explained step by step in the order shown in the figure numbers below. The figure initially shows the lower part of the shell and the internal components except the release mechanism.

[0046] to this end, Figure 2 The auto-injector is shown with the push cover 27 removed, and the needle 5 can be seen. When the drive mechanism is in this state, the auto-injector is ready to inject the active ingredient in the syringe 3. The torsion spring 9 is in a tensioned state, that is, its movable spring leg 8 is in the pre-tensioned position shown in the figure, and is held in this position because the piston slide 22 is locked by a releasable pawl. The release structure is shown in FIG. Fig. 22 As shown. When in use, the user presses the protective cavity 35 (not shown) on the body where the injection is required. The housing 1 is slightly pushed in, and the needle 5 pierces the skin, triggering the injection at the same time, as described below. After the trigger, the movable spring leg 8 starts its pivoting movement to cause the injection. Then, the syringe 3 and the needle 5 are automatically retracted into the housing together, so that the needle 5 disappears in the housing 1 and will not harm or infect anyone.

[0047] Figure 3 For Figure 2A rear view of the auto-injector in the state shown. In the figure, the syringe support can be seen, that is, the rods 18, 19 cut into a U shape at the top, on which the inserted syringe 3 and its barrel 4 are placed. It can also be seen that the stopper 20 prevents the syringe 3 from being pushed further backward into the housing 1, and the driving ramp 21, which is formed on the leg 29 and has its root in the housing base, and the piston slide 22 can be driven onto the ramp to release the rear end of the syringe 13.

[0048] Figure 4 The autoinjector is shown shortly after the injection is started, and the piston 6 has been slightly retracted into the barrel 4 of the syringe. As shown in the figure, the movable spring leg 8 has traveled a distance, thereby pushing the rod 7 forward along the guide 11 of the piston slider 22, and the front end of the rod 7 is hinged to the piston slider 22 through the joint 28. The front end of the piston 6 is inserted into the barrel 4 of the syringe 3 and pushes the sealing pin 26 forward. In this way, the active substance in the barrel 4 is injected through the needle 5. Figure 5 Shows that Figure 4 The rear view of the automatic syringe in the illustrated state. The sealing pin 26 is located in front of the front end of the piston 6 in the barrel 4 of the syringe 3.

[0049] Figure 6 The self-service syringe is shown in a further injection process, wherein the piston 6 has traveled approximately half of the stroke. At this point, the sealing pin 26 is approximately located in the middle of the barrel 4 of the syringe 3. The movable spring leg 8 continues to pivot, and the pivot rod 7 connected thereto also continues to pivot. As shown in the figure, the spring leg 8 forms a knee joint 2 together with the pivot rod 7. As the spring leg 8 continues to pivot, the force transmitted by the spring leg 8 to the pivot rod 7 naturally decreases. At the same time, the more slender the knee joint 2 is, the greater the impact force on the piston slide 22 is. This is very important because it ensures that the injection force acting on the sealing pin 26 remains uniform throughout the injection process. Figure 7 Shows that Figure 6 Rear view of the autoinjector in the illustrated state.

[0050] Figure 8 The auto-injector during the injection process is shown, wherein the piston 6 has traveled about two thirds of its stroke for injecting the active substance. Therefore, the movable spring leg 8 further pivots, and the pivot rod 7 hinged thereto also further pivots, so that its front end further pushes the piston slide 22 forward along the guide rail 11. Fig. 9 Shows that Figure 8 Rear view of the autoinjector in the illustrated state.

[0051] Fig.10 The autoinjector is shown during an injection process, wherein the piston 6 in the barrel 4 has travelled almost its full stroke to inject the active ingredient. Fig.11The rear view of the self-help syringe in this state is shown. When driven to the flange 14 at the rear end 13 of the syringe 3, the barb 10 on the piston slide 22 quickly connects with the rear end of the syringe 3, thereby cooperates with the flange 14.

[0052] Fig.12 The auto-injector is shown in the final stage of the piston movement. The sealing pin 26 in the syringe 3 or its barrel 4 has almost reached the front end. The pivot rod 7 for pushing the piston slide 22 forward is only slightly deviated from the direction of the guide rail 11. As shown in the figure, the barb 10 is already halfway to the rear end flange 14 of the syringe 3. At the same time, the piston slide 22 has moved a little on the inclined surface 21 to press the elastic leg 29 downward, whereby the stop 20 releases the flange 14, so that the syringe 3 can be pulled back without being hindered by the barb 10. Fig.13 A rear view of the autoinjector is shown in this state.

[0053] Fig.14 The autoinjector is shown at the end of the piston movement. At this point, the pivot rod 7 is almost fully aligned with the guide rail 11, and the piston 6 is pushed forward into the barrel 4 of the syringe 3 almost as far as possible. Fig.15 The rear view of the autoinjector in this state is further shown, wherein the barb 10 is driven onto the flange 14 after hooking onto the flange 14 of the end 13 of the syringe 3. To this end, the barb 10 is slightly elastically pushed upward relative to the piston slider 22, and then, under the action of the elastic restoring force, the barb 10 falls again like a latch behind the flange 14 and hooks onto the flange 14. The piston slider 22 moves upward onto the rising slope 21 and presses the elastic leg 29 downward, so that the stopper 20 moves downward, so that the syringe 3 can be pulled back into the housing 1 without hindrance.

[0054] Fig.16 The autoinjector is shown after the injection phase is completed. At this point, the barb 10 is hooked on the flange 14 of the barrel 3. The piston 6 reaches the front end of the barrel 4 with the sealing pin 26. At this point, the pivot rod 7 is approximately in line with the piston slide 22 and the guide 11 of the piston 6. Because the barb 10 is hooked on the flange 14, the barrel 3 is now ready to be retracted by the piston slide 22 and the barb 10 in a subsequent stage. Fig.17 A rear view of the autoinjector is shown in this state.

[0055] Fig.18 The initial stage of the retraction of the syringe 3 is shown. Here, the pivot rod 7 has been further pivoted beyond the direction of the guide rail 11 and pulled into the housing 1 through the front connecting piece 28 on the piston slide 22. Therefore, the barb 10 on the piston slide 22 pulls the syringe 3 back at its rear flange 14 to pull the needle 5 into the housing 1 as well. Fig.19A rear view of the autoinjector is shown in this state of the pivot lever 7. In this figure it can also be seen how, by pressing down on the resilient legs 29 and the stop 20, the barrel 3 and its flange 14 can be retracted unhindered by means of the barb 10 and the piston slide 22.

[0056] Fig. 20 The autoinjector is shown when the pivot lever 7 has completed all the movements with the torsion spring 9. The movable spring leg 8 has reached the stopper 25 in the housing 1 and the pivot lever 7 has pivoted to this position. Since the front end of the pivot lever 7 is hinged to the piston slide 22, the pivot lever 7 has retracted the piston slide 22 and the entire syringe 3 via the barb 10, so that its needle 5 is finally completely pulled into the housing 1 and can no longer harm or infect anyone. Finally, Fig.21 The rear view of the auto-injector in this state is shown. The syringe 3 is pulled back through the stopper 20 by the barb 10 hooked on the flange 14. The needle 5 of the syringe 3 has disappeared in the housing 1.

[0057] Understandably, Figures 1 to 21 The lower housing part shown has an identical upper housing part which can be snapped onto the lower housing part to form a closed housing 1, so that the self-injector can be used as Fig. 22 shown.

[0058] In its front part V, the syringe 3 is inserted therein, and the housing 1 of the autoinjector forms a channel with a rectangular cross section, in which the piston slide 22 is also introduced with its upper side, that is, also on the inner side of the upper housing part. The rear part H of the housing 1 widens from the rectangular channel in a fan-shaped manner on both sides to the rear. The needle 5, the torsion spring 9 and the tube 47 ( Figure 1 The syringe 3 (shown) is the only metal part of the auto-injector with the syringe. All other parts of the auto-injector can be made of injection-molded plastic, and if necessary, the puller can also be made of plastic. Assembly is simple because only a few parts need to be assembled, that is, in addition to the syringe 3 consisting of the barrel 4, the sealing plug 26, the enclosed active ingredient and the needle 5 with the protective cap 27, there are only seven parts, namely:

[0059] 1. Lower shell part

[0060] 2. Upper shell part

[0061] 3. Torsion spring 9

[0062] 4. Pivot rod 8

[0063] 5. Piston slide block 22 with integrally formed piston 6 and barb 10

[0064] 6. A release slider 30 for release, with a release displacer 45 (such as Fig.23 (shown)

[0065] 7. A puller 46 with a tube 47 and a barb 48 (e.g. Figure 1 The release slider 30 with the release displacer 45 and its function are shown in detail in Figure 23-34 .

[0066] The assembly process is as follows. Fig.35 As shown, the lower housing section is located on the auxiliary assembly tool 49. The torsion spring 9 is inserted on the bolt 16 in the housing 1, so that the spring leg 17 is fixed and hits in the correspondingly shaped retainer 24 and remains in contact with the housing 1, and the spring leg 8 is pre-tensioned to its initial position by applying an action force and temporarily locked in its position (for example, with the help of a cam 52 on the mounting plate 49). The pivot rod 7 is clamped in the joint 28 at the rear end of the piston slide 22. Now, the pre-assembled part of the pivot rod 7 and the piston slide 22 is inserted into the guide rail 11 of the lower housing section. At the same time, the rear end of the pivot rod 7 is connected to the end of the movable spring leg 8 via the connection point 2. The puller 46 and its tube 47 with barbs 48 are placed on the protective cavity 35 of the release slide 30. Now, the syringe 3 consisting of the barrel 4, the sealing pin 26, the enclosed active ingredient and the needle 5 with the protective cap 27 is pushed in from the rear end of the trigger slider 30 with the puller 46 attached, so that the protective cap 27 passes through the hole 37 of the protective cavity 35 and engages with the barb 48. The preassembled part of the trigger slider 30, the syringe 3 and the puller 46 are inserted into the lower part of the housing so that the piston 6 at the front end of the piston slider 22 is inserted into the open end of the barrel 4 of the syringe 3 without contacting the sealing pin 26. Now, the upper housing part is placed on the lower housing part. The release pawl 33 of the upper housing part is inserted into the groove 32 of the piston slider 22. The assembled housing can now be removed from the mounting plate 49. This causes the cam 52 to release the preloaded spring leg 8. However, the piston slider 22 is released by the release pawl 33, which is initially pulled back by the release slider 30, so that the spring leg 8 remains in a tensioned state. The release pawl and the release of the auto-injector are described in detail in the following figures.

[0067] Figures 22 to 32 The auto-injector is shown with the release slider 30 inserted. Initially, such auto-injectors are Fig. 22 As shown, the housing is closed. Fig.23 In the figure, the upper part of the housing has been removed again, and it can be seen that the autoinjector is here in the tensioned initial position, i.e. the torsion spring 9 is tensioned. Since the piston slide 22 is blocked and pulled back by the pawl, the movable spring leg 8 is pulled back in this tensioned state. The release slide 30 forms a displacer 45 at its rear end and is guided on the housing by the slide 40, which is now inserted here for the first time. On the other side of the slide 40, a second guide plate 41 is formed on the protective cavity 35, which can also move along the housing.

[0068] Fig.24Details of the auto-injector locking mechanism are shown. Fig.23 , which shows the structure in a position rotated 180° around the longitudinal axis of the housing 1, without the lower housing part, but with the upper housing part visible inside and with an enlarged view at the bottom right of the circular cutout. It can be seen here that the lower edge 36 of the piston slide 22 is at the top in this figure, which is the bevel or ramp 23, by which the piston slide 22 can be moved onto the bevel 21 to push away the elastic leg 29 and thus the stop 20, so that the syringe 3 can be retracted into the housing 1 without hindrance.

[0069] The enlarged view of the locking mechanism shows the pawl 33 and the displacer 45, where the pawl 33 can swing laterally in the housing, and the displacer 45 now leans laterally against the pawl and fixes the pawl 33 in the groove 32 of the piston slide 22, so that the piston slide 22 cannot move in the direction of the syringe 3.

[0070] The sequence of actions after the automatic injector is triggered is described below. Fig.25 The rear part of the upper housing part with an opening 44 through which the interior can be seen is shown. In this opening 44, the latch 33 can be seen at the end of an elastically pivotable arm 34 formed in the housing part. The latch 33 can be elastically pivoted back and forth at right angles to the arm. The displacer 45 of the release slide 30 contacts the outer edge of the pawl 33 at the rear in the figure, so as to press the pawl into the groove 32 of the piston slide 22 against the elastic restoring force of the pawl 33. The piston slide 22 is thus blocked and cannot be moved in the direction of the syringe 3. The spring leg 8 and the pivot arm 7 are also unable to pivot.

[0071] exist Fig.26 , a further enlarged view of the opening or recess 44 in the upper part of the housing shows how, by applying the autoinjector, the release slide 30 is pushed back into the housing, i.e. the protective chamber 35 is pressed onto the planned insertion point according to arrow B. As a result, the displacer 45 is pushed through the latch 33 in a sliding manner. Thus, the displacer 45 slides through the release slide 30 at the latch 33. The sliding does not stop until the rear edge 39 of the release mechanism 45 passes the latch 33 and releases it to pivot towards the release slide 30. As a result, the arm 34 of the pawl 33 is turned out of the recess 32 on the piston slide 22 (as shown by arrow A) and is suddenly released in order to move in the direction of the syringe 3. The piston slide 22, driven by the pre-tensioned spring leg 8 and the pivot rod 7 hinged thereto, forms a toggle with it and then pushes the piston 6 in the syringe 3 forward according to arrow C and injects the active substance into the tissue through the needle.

[0072] Fig. 27First, the initial stage after the release of the movable spring leg 8 after the pawl 33 has been removed is shown. It has already rotated a few degrees clockwise and accordingly moves the articulated pivot lever 7 together, however, from the observer's point of view, the pivot lever 7 therefore moves counterclockwise around the active pivot point 28. Fig.28 The movement of the spring leg 8 over a rotational path of approximately 30° is shown.

[0073] Fig.29 The autoinjector is shown after the spring leg 8 has moved approximately halfway. Fig.30 In the embodiment of FIG. 1 , the spring leg 8 has reached half of its pivot stroke. At this point, the pivot rod 7 extends almost in the same direction as the piston movement. Fig.31 In the embodiment shown in FIG. 1 , the spring leg 8 covers approximately 2 / 3 of the spring leg travel and the pivot rod 7 is approximately in the direction of movement of the piston. Fig.32 The state when the spring leg 8 has traveled 3 / 4 of the spring leg path is shown. Fig.33 The situation is shown when the movable spring leg 8 has reached its end position at the stop 25 and the corresponding pivot lever 7 articulated thereto has also reached this position.

[0074] at last, Fig.34 The two housing parts of the self-injector are shown to be locked together to illustrate its release mechanism, the lower housing part on the left and the upper housing part on the right. Fig.34 The working principle of the trigger mechanism is described in detail. When the syringe is inserted into the autoinjector, i.e. on the two rods 18, 19 with semicircular supports in the lower housing part, the syringe needle 5 extends into the protective cavity 35 and is completely surrounded by the protective cavity 35, i.e. does not extend out of the protective cavity 35, although the protective cavity 35 has a circular hole 37 at the front and is open there. The puller 46 and its tube 47 with barbs 48 are inserted into this hole 37 and pass over the push cover 27. By pulling it out, the push cover 27 can be pulled out of the hole 37 in the front part of the protective cavity 35 with the barbs 48 with the tube 47 and removed. The needle is still hidden in the protective cavity 35. Here, the injection is triggered by the trigger slide 30, which is integrally connected to the front part of the protective cavity 35 and ends at the front wedge-shaped displacer 45 at its rear end. When the autoinjector is pressed against the body in the initial state, the protective cavity 35 and the release slide 30 in the housing 1 are pushed back into the housing 1 of the autoinjector (as shown by the arrow on the protective cavity 35). The protective cavity 35 moves backwards over the needle tip 5 with its front hole 37, exposing the needle tip 5 and allowing it to penetrate the skin and muscle. At this time, the syringe 3 must be activated, that is, the piston in the syringe 3 sends the active ingredient in the syringe body forward and is delivered to the body through the needle tip.

[0075] The release process is as follows: when the autoinjector is assembled, the upper housing part shown on the right (whose interior is visible) is pivoted by 180° and snaps onto the lower housing part shown on the left (as indicated by the two curved arrows). The upper housing part shown on the right has an opening or recess 44 in the rear region, in which an arm 34 is formed, which can be pivoted elastically to the left and to the right and forms a latch 33 at the front, which in the assembled state projects into the recess 32 of the lower housing part shown on the left, so that it can be seen from the outside (i.e. from above the upper housing part) when the autoinjector is assembled. This is of course not a condition for the function, but only serves to simplify the production of the moving parts without the use of a slide in the injection mold. When the two housing parts are assembled, this latch 33 presses into the recess 32 of the rear widened hinge part 31 of the pivot lever 7 on the piston slide 22 and blocks it, i.e. prevents the piston slide 22 from moving. The hinge point 2 of the pivot lever 7 can be pivoted along the path shown in dashed lines at the free end of the movable spring leg 8 and is connected in an articulated manner to the piston slide 22, the other end of which is located at the hinge point 28. This can only be moved forward along the guide rail 11 towards the syringe 3, but only when the piston slide 22 is released and moved forward towards the syringe 3, i.e. when the pawl 33 no longer extends into the groove 32 of the hinge part 31 of the piston slide 22. If the protective cavity 35 is now pushed back due to the positioning of the syringe and the release slide 30 formed thereon, the wedge displacer 45 pushes over the elastically pivotable pawl 33, and when its rear edge 39 passes this pawl 33, it pivots from left to right along the inclined surface on the groove 32 of the housing part, as shown on the left, and thus leaves the groove 32. The connecting rod 31 and the piston slide 22 are prestressed by a torsion spring, which acts on the pivot lever 7 and wants to push it forward towards the syringe. When the pawl 33 slides out of the groove 32 on the hinge part 31, the piston slide 22 suddenly releases to cause a longitudinal displacement in the direction of the syringe 3. As a result, the torsion spring 9 and its spring legs 8 can move the pivot rod 7 hinged thereon along the semicircular imaginary line 38. In the first half of this movement, the piston slide 22 is strongly pushed toward the syringe 3 and actuates the piston 6. In the second half of the movement, the piston slide 22 retracts until the movement of the spring legs 8 and the pivot rod 7 ends with the stop 25. As mentioned above, the second half of this movement pulls the syringe 3 itself back a short distance into the housing 1 of the auto-injector, so that its needle 5 disappears in the housing 1 and can no longer hurt anyone. The role of the ribs 44, 42 in the housing part is to strengthen the housing part.

[0076] at last, Fig.35A special fixing plate for mounting the auto-injector is shown. For this purpose, the fixing plate 49 has a centering cam 50 and a positioning web 51 on the other side. The lower housing part of the housing 1 of the auto-injector is designed with corresponding grooves, which fit precisely on the centering cam 50 and the positioning web 51. This ensures that the locking cam 52 extends into the housing 1 through the lower housing part in the correct position to block the spring leg 8 of the torsion spring. As long as the auto-injector is placed on this locking plate 49, it cannot be triggered. It can be said that the auto-injector is only unlocked when it is lifted from this safety plate 49. After removing the puller, it is unlocked and can be used. By pressing the protective cavity 35 against the location on the body where the active substance is to be injected, the release slider 30 is pushed into the housing 1, exposing the needle 5 of the syringe, and the automatic injection is realized. The piston 6 in the syringe 3 is pushed forward by the torsion spring 9, and then the syringe 3 is completely pulled into the interior of the housing 1, so that the needle 5 disappears in the housing 1. Now, the auto-injector has been used and will no longer harm or infect anyone, and can also be discarded.

[0077] Reference numerals list:

[0078] 1 Shell

[0079] 2 Connection point / knee joint of spring leg 8 and pivot rod 7

[0080] 3 Syringes

[0081] 4 Syringe barrel

[0082] 5. Needle for syringe

[0083] 6 Piston

[0084] 7 Pivot lever

[0085] 8 torsion spring movable legs

[0086] 9 Torsion spring

[0087] 10 Barb

[0088] 11 Piston guide

[0089] 12 Sliding slope at the bottom of the barb

[0090] 13 The rear end of the syringe 3

[0091] 14 is the flange at the rear end 13 of the syringe barrel

[0092] 15 Torsion spring winding shaft

[0093] 16 Torsion spring bolt

[0094] 17 Fixed spring legs

[0095] 18, 19 Top U-shaped rod

[0096] 20 syringe 3 rear end stopper

[0097] 21 Inclined surface at stopper 20

[0098] 22 piston slider

[0099] 23 inclined surface on piston slide 22

[0100] 24 Torsion spring positioner

[0101] 25 Limit cam for pivot range of movable spring leg

[0102] 26 Seal pin at the front of piston 6

[0103] 27 needle 5 push cover

[0104] 28 Pivot point between pivot lever 7 and piston slide 22

[0105] 29 Legs for entry ramp

[0106] 30 Release Slide

[0107] 31 Connecting rod part of piston slider 22

[0108] 32 Recess for the pawl 33 in the piston slide 22

[0109] 33 Release the latch

[0110] 34 handle 33 elastic arm

[0111] 35 Release the protective cavity in front of the slide 30

[0112] 36 The lower edge of the piston slide 22

[0113] 37 Hole in protective cavity 35

[0114] 38 semicircular motion line

[0115] 39 trailing edge on displacer 45

[0116] 40 Release the slide plate of the protective cavity 35 of the slide block 30

[0117] 41 Release the guide plate on the protective cavity 35 of the slide 30

[0118] 42 Transverse ribs on lower shell part

[0119] 43 Ribs on the upper part of the shell

[0120] 44 The opening or groove in the upper part of the housing is used for the elastic arm with latch 33

[0121] 45 Displacer

[0122] 46 cubic puller

[0123] 47 Barbed Tube

[0124] 48 Barb in tube

[0125] 49 Locking plate

[0126] 50 Centering cam on locking plate

[0127] 51 Positioning lever on locking plate

[0128] 52 Locking cam on locking plate

[0129] V front housing part

[0130] H rear housing part

Claims

1. An automatic syringe with stored energy for injecting a contained liquid active substance, comprising a housing (1), a support (18, 19) for holding a syringe (3) to be inserted, the syringe (3) having a barrel (4), a sealing pin (26) and a needle (5), the active substance being injected hydraulically through the needle (5), characterized in that: The piston (6) can be actuated by a piston slide (22), which is guided along a guide rail (11) in the housing (1) by a pivot rod (7) hinged thereto, the other end of the pivot rod (7) being hinged to a pivotable spring leg (8) of a prestressed torsion spring (9) having a plurality of coils, wherein a second spring leg (17) is fixedly locked to the housing (1) and can trigger a pivoting movement of the pivotable spring leg (8) by releasing the prestressed torsion spring (9), wherein in a first pivoting phase of the pivotable spring leg (8) and the piston slide (22) hinged at its end, the piston can be pushed into the syringe (3) so that the barb (10) on the piston slide (22) can hook onto the syringe (3), and then, in a subsequent pivoting movement of the pivotable spring leg (8) and the piston slide (22), the syringe (3) can be retracted into the housing (1).

2. The automatic syringe according to claim 1, characterized in that: The piston (6) can be pushed into the barrel (4) of the syringe (3) by acting on its piston slider (22), the piston slider (22) being guided on a groove-shaped guide rail (11) in the housing (1), the barb (10) having a sliding slope (12) extending obliquely relative to the sliding axis, the rear end (13) of the syringe (3) having a flange (14), the flange (14) radially extending out of the barrel (4) of the syringe, the barb (10) can be elastically pushed over the flange by its sliding slope (12) and hooked on the end of the sliding slope (12) by elastic rebound, so that the syringe (3) can be retracted into the housing (1) in the second pivoting stage of the pivot rod (7) until its needle (5) is completely inserted into the housing (1).

3. An auto-injector according to any one of the preceding claims, characterized in that The piston (6) can be operated by a pivot rod (7) hinged to its rear end, wherein a torsion spring (9) is mounted with its winding axis (15) on a bolt (16) in the housing (1), and its fixed spring leg (17) is supported on the housing (1), while another movable spring leg (8) is hingedly connected to the rear end of the pivot rod (7) under the tension of the torsion spring (9), and the front end of the pivot rod (7) is hingedly connected to the rear end of the piston slider (22). When the torsion spring (9) is triggered, the pivot rod (7) can pivot around the hinge point on the piston slider (22) in the first stage of the syringe until it is located on the displacement axis of the piston (6). In the second pivoting stage, when it is further pivoted, the syringe (3) is retracted into the housing (1).

4. An auto-injector according to any one of the preceding claims, characterised in that A support for holding a syringe (3) to be inserted having a barrel (4) and a needle (5) has at least two webs (18, 19), which are recessed in a U-shaped manner at the top, into which the barrel (4) of the syringe (3) fits in a form-fitting manner, and the housing (1) forms a stopper (20), against which the syringe (3) abuts with a flange (14) at its rear end, so that when the needle is inserted into tissue, it will not shift into the housing (1).

5. An auto-injector according to any one of the preceding claims, characterised in that A support for holding a syringe (3) to be inserted with a barrel (4) and a needle (5) has at least two webs (18, 19) which are recessed in a U-shaped manner at the top, into which the barrel (4) of the syringe (3) fits in a form-fitting manner, and the housing (1) forms a stopper (20), on which the syringe (3) hits with its flange (14) at the rear end, and the stopper (20) forms an inclined slope (21) in the direction away from the syringe (3), and at the piston (6) At the rear of the piston slider (22), a forward-rising inclined surface (23) is formed at its lower edge. In the final stage of the forward movement, when its barb (10) moves on the rear flange (14) of the syringe, the piston slider (22) moves to the inclined surface (21) in front of the stopper (20) through the forward-rising inclined surface (23), thereby displacing the elastic legs (29) and the stopper (20) thereon, whereby the syringe (3) can then be retracted into the housing (1) unhindered by the barb (10).

6. An auto-injector according to any one of the preceding claims, characterised in that Except for the needle (5), the torsion spring (9) and the puller tube (47) of the puller (46), which are made of metal, the other parts are composed only of injection-molded plastic parts.

7. An auto-injector according to any one of the preceding claims, characterised in that The housing (1) comprises a lower part containing all the components for holding and actuating the syringe (3) and its retraction, as well as a trigger slide (30) with a displacer (45) for triggering, and a corresponding upper part, which is equipped with a latch (33) formed on the end of an elastic pivotable arm (34), thus having transverse flexibility and being able to be snugly snapped onto the lower part.

8. An auto-injector according to any one of the preceding claims, characterised in that The trigger slide (30) forms a cubic protective cavity (35) for the needle (5) at the front, a displacer (45) for lateral blocking and passing the trigger latch (33) at the rear, and a lateral slide (40) and a lateral guide (41) located opposite it, through which the trigger slide (30) is guided in the housing (1) parallel to the syringe (3).

9. An auto-injector according to any one of the preceding claims, characterised in that In the initial state, the movement of the piston (6) in the cylinder (4) is ensured by the piston slider (22), the piston slider (22) forming a groove (32) at its rear end, and a release latch (33) that is elastically pivotable on the other housing part extends into the groove, and wherein the release latch (33) can be pushed by a displacer (45) formed at the rear end of the slide rod (30), and a protective cavity (35) is formed at the front, which surrounds the needle tip on all sides. When the self-injector is placed in the target position and pressure is applied to the protective cavity (35), it can push through the release latch (33), so that after the rear edge (39) of the displacer (45) passes the release latch (33), the latch (33) pivots out of the groove (32), thereby releasing the piston slider (22) to move toward the syringe (3), so that the pivot rod (7) can be pivoted to the other side in the housing (1) by the torsion spring (9).

10. An auto-injector according to any one of the preceding claims, characterised in that A puller (46) having a metal tube (47) is inserted into the push cover (27) of the needle (5), and the metal tube (47) is provided with a barb extending inwardly. By removing the puller (46) from the housing of the needle (5) of the syringe, the push cover (27) can be released, but still remains in the protective cavity (35), and it can be pushed back into the housing (1).

11. An auto-injector according to any one of the preceding claims, characterised in that A channel of rectangular cross-section is formed in the front part (V) of the housing (1), into which the syringe (3) is inserted, and the rear part (H) of the housing is widened in a fan-shaped manner from both sides of the channel and is placed on the fixing plate (49) so that the locking cam (52) extends out of the groove in the housing (1) and blocks the spring leg (8) of the torsion spring (9).

Images