Automatic injection device

ES 2 294 594 T3

DESCRIPTION

Self-injection device.

Self-injection devices are used to administer products, especially liquids with a medicinal or cosmetic effect. Also, after activating a drive mechanism, an injection needle is automatically injected, by means of which the product is administered, in a certain section in a tissue.

A self-injection device, as corresponds to the invention, comprises at least one housing, a container movably contained within the housing, from which a product to be administered is expelled by a needle located at the outlet of the container by advancing a plunger, and a drive part of an advance device, contained in a displaceable way in the housing than in a self-injection, advances the container relative to the housing to a predetermined anterior position to inject the needle, and advances the plunger in the container to eject the product. As soon as the container reaches its previous position in a self-injection, the needle has been moved forward in a certain span, together with the container, likewise, by determining the span, the depth of penetration of the needle is also basically determined.

This type of self-injection device is known from US-PS 159,192, EP 0 516 473 B1 and US-PS 5,643,214.

In the case of known self-injection devices, the advancement of the container together with the needle applied therein is carried out by the pressure of the driver on the plunger.

From EP 0 824 923 A1 a self-injection device is known, in which the advancement of the container relative to the housing and the advancement of the piston in the container are decoupled from each other. Disengagement is accomplished by releasing a ratchet gear.

The present invention aims to create a self-injection device with a simple mechanical decoupling of the advance movement of the container and the advance movement of the plunger in the container, which allows a smoother passage between both advance movements.

According to the invention, the driver in the self-injection device of the type described above is uncoupled from the plunger until reaching the previous position of the container, and is uncoupled from the container upon reaching the previous position of the container and coupled to the plunger to move the plunger. in the container. The forward movement of the container to inject the needle is not effected by the plunger, that is, there is no drive connection between the drive part and the plunger during this phase of movement. In this way, it is safely ruled out that already during the advance of the container product is expelled by eventual, even small movements of the plunger in the container, that is to say, in relation to the container. By disengaging the driver from the container in the previous position and is only now engaged with the plunger, the plunger is not advanced before the needle has been injected to the desired depth into the tissue. The separation in the actuation of the advance movement of the container and the advance movement of the plunger in the container increases the dosage precision, since pressure is no longer exerted on the plunger when advancing the container, which is why it is possible to eject the product too early.

The driver can act directly on the container to advance the container.

Preferably a transmission part is provided, which is driven by the drive part in a forward movement, which in turn acts on the container and / or on a container carrier and thus advances the container. The transmission part can also be a container holder, but is preferably configured as a separate part from it.

Between the drive part and the transmission part there is the disconnectable coupling. After disconnecting the coupling in the previous position of the container, another advance movement of the driver, namely to advance the plunger, no longer produces any further advance of the transmission piece. The drive part is free from the transmission part, at least in relation to its own forward movement. It just presses against the plunger and thus advances it into the container. Preferably, the transmission part is contained by the housing so that it can be moved in the opposite direction to the forward movement of the piston.

According to the present invention, the coupling between the driver and the container includes at least one continuous connection between the driver and the container or the transmission piece.

Preferably a coupling is used which acts as a continuous and drag connection to couple and uncouple the driver with and from the container, as well as with and from the piston. In this embodiment as well, the coupling is preferably configured between the drive piece and a transmission piece, although a coupling directly with the container could also be envisaged.

The coupling is preferably formed by a quick connection. As the driver is advanced, a latch presses against a contact surface and thus advances the container. When the container

ES 2 294 594 T3 reaches its previous position, in which it is in mutual contact with the housing, the quick connection is disconnected by the actuating force that is still exerted on the driver. The driver is coupled to the plunger and moved further forward, free from the container or free from the transmission part. A slight bump when reaching the previous position of the container can be absolutely desirable and helpful.

At least one of the means making up the coupling is configured flexibly, preferably elastically flexibly. One or more latches can be configured directly on the drive part, which thereby presses against a contact surface of the container or of the transmission part, if such a part is used. This type of latch can also be provided on the transmission part.

Especially preferred for the design of the coupling is the inclusion of a third coupling means, which is then flexibly, preferably elastically flexibly. Advantageously, the third coupling means is a flexible ring, especially an elastic ring, which is wedged between two mutually facing surfaces of the drive part and of the transmission part, and slides over one of these two contact surfaces. contact as soon as the container reaches its previous position.

The present invention can be advantageously applied to self-injection devices, in which the container is formed by a so-called multi-chamber ampoule. Through this type of multi-chamber ampoules, the product to be administered is just obtained by mixing the contents of multiple separate chambers, when assembling the device. Each of the chambers arranged one behind the other is closed inversely by a piston movable in the container. To intermix, a mixing piece is pressed against the rear piston and this one presses, in its forward movement in the container, each of the pistons up to the front piston. As it advances, links are established or established with the respective anterior abutting chamber, so that the contents of the posterior chamber are displaced towards the respective anterior abutting chamber.

According to the present invention, the mixing part, especially a mixing tube, known per se, forms at the same time the transmission part to move the container forward. According to the invention, the mixing piece is assigned a double function. This is achieved, in terms of construction, preferably by having the mixer part having a bridge protruding radially outwards, preferably in the form of a circular handle, with which it presses against the rear front surface of the container or, if preferred, against a rear contact surface of a container carrier, which draws the container with it in its forward movement induced by the mixing piece. Also the front position of the container is preferably defined by a stop of said container holder against the housing.

The casing can enclose both the container as well as the entire actuating device, preferably being in the shape of a sleeve, but in its most general configuration it serves only as a base part, in relation to which the movement movements of the container are carried out and the displacement movements of the driver of the actuating device and therefore should not be understood exclusively but preferably as a casing.

Exemplary embodiments of the invention will be explained below from Figures 1 to 6. It is shown:

Figure 1 a self-injection device with continuous and drag coupling,

Figure 2 a self-injection device with continuous joint coupling,

Figure 3 the transmission part of the device according to figure 2,

Figures 4, 5 the lock for the protective cap of the needle of the device according to figure 2 and

Figure 6 shows a self-injection device with a two-chamber ampoule and a mixing tube configured as a transmission part.

Figure 1 shows a self-injection device in the shape of an injector pencil, in longitudinal section.

The pencil has a hollow cylinder-shaped housing, in the exemplary embodiment, a circular cylindrical shape, with a needle guard 1 at its front end, a front housing bushing 2 attached to it, and a rear housing bushing 3 attached thereto, closed on the front face by a carcass layer 4. The front casing bushing 2 comprises a cylindrical container B, which in turn is held centrally, in a container carrier 30 in a direction coaxial to the longitudinal central axis of the casing. The container carrier 30 is also bush-shaped and runs forward on centering tabs, which press against the edge of the perimeter of the container B and center it on the front housing bushing 2. The container carrier 30 is movable along the central longitudinal axis of the housing in both directions. As the container carrier 30 moves, the container B held therein moves. In turn, an injection needle N arranged at the outlet at the front end of the container B is moved forward and injected in the course of a self-injection into and under the skin of a patient.

ES 2 294 594 T3

In container B a plunger K is movable along the central longitudinal axis of container B. As plunger K advances a product contained in container B, in the exemplary embodiment, a medicated liquid, for example insulin, is displaced by the outlet and through the injection needle N for the expulsion of the product. A piston rod protrudes rearwardly from the plunger K, projecting over a rear edge of the container.

Container B is flanged-expanded along its rear edge. The container carrier 30 is also correspondingly expanded at its rear end, and extended with an expanded cross-section, overcoming the container by a portion, in the form of a sleeve. Container B lies in the installed state with its subsequent expansion adjacent to the surface of the container carrier handle 30, oriented toward this expansion. A side surface of the container carrier 30 is surrounded by a compression spring serving as a return element 33, which is in contact with a front end next to the handle surface of the front half of the housing 2, and from there it does not fully protrude to an opposite surface 31, which is shaped by the expansion of the container carrier 30 and is oriented towards the surface of the handle named above, of the front casing of the casing 2. By advancing the carrier of the container 30 and thus the container B the compression spring 33 is pressed between both facing surfaces and thereby dampens the advance movement when injecting the needle N. The surface 31 touches, when advancing, against a surface of the handle, formed in the area of ​​a stepped expansion of the sleeve of the front housing 2. The stop of the surface of the handle 31 of the container holder 30 defines an anterior position of the container B and thus that length with which the needle N, in the anterior position of the container B, protrudes to the front edge of the housing, therefore which, also at the same time, the injection depth of needle N is determined, assuming a correct support of the pencil on the skin.

An actuating device for moving the container B and for advancing the piston K in the container B is formed by an actuating element 5 formed by a compression spring and a driver 10. The actuation can also be effected by means of an agent. pressure. The driver 10 is essentially sleeve-shaped, with a sleeve kettle open on the rear side, closed by a base. At its front end, the drive piece 10 continues in the shape of a sleeve in the direction of the piston rod, a comparatively short section projecting through the aforementioned base. The continuation is formed by a seal 11 to press against the plunger rod and advance the plunger K into the container B.

In the represented output state of the injector pen, there is no direct pressure of the seal 11 against the piston rod. Rather, a small free space remains in the exit position between the seal 11 and the rear front surface of the piston rod. In the depicted output state of the pencil, in which container B is in its rearward displacement position, driver 10 is coupled to container B. The drive piece 10 is directly coupled with the transmission piece 20, which acts directly on the container B. In the same way, the transmission piece 20 could act on the container carrier 30, then drives should be provided between the container carrier 30 and container B. In principle also the driver could press directly on a container or a container holder, to advance the needle.

The transmission part 20 is formed by a hollow body, in the rear area of ​​which a circular handle 22 is formed, through a transverse reduction, said handle serves as a front contact surface for an elastic deformation ring 21. The deformation ring The elastic 21 is supported in a groove running in the outer lateral surface of the driver 10, in the area of ​​the seal 11, secured against displacement relative to the driver 10. The ring 21 can be configured as a closed flexible ring, but preferably it consists of a rigid material such as plastic or metal, and is cut-out in one part, so that the ends of the ring 21 facing that point can be moved a little more towards each other. and thereby the diameter of the ring can be reduced. This yielding ring 21, the handle 22 and the wall 12 facing the handle 22 of the groove form a coupling that is based on a continuous and detachable connection between the driving piece 10 and the transmission piece 20. The ring 21, as a pressure and coupling agent, could be configured as a flange on the driver 10 or the transmission part 20, which would then develop into collapsible tabs.

The drive part 10 is held against the pressure of the actuating part 5 in the exit position shown in figure 1, by means of a release tab 7 formed in the holding and release sleeve 6. The joint is released by pressure inward of release tab 7.

To inject the product, rest the pencil with the front edge of the needle guard 1 on the skin, exerting gentle pressure, after removing the protective cap from the needle. The release tab 7 is then depressed and thereby the connection between the release sleeve 6 and the housing is released. The driver 10 is pressed forward by the pressure of the advance element in the housing. By coupling, the forward pressing force of the driver 10 is transmitted from the wall of the groove 12 to the ring 21 and from the latter to the handle 22, and thus to the transmission part 20. The transmission part 20 presses with a front front surface against the container B and the container carrier 30, which, with the exception of possible surface friction forces, are in principle pressed forward in the housing without resistance, by the pressure of the transmission part 20. Needle N, which indicates exactly in the direction of advance, is pressed forward, protruding above the leading edge of needle guard 1 and enters the tissue. The advance of container B and with it. the injection depth of the needle N is limited by stops on the surface of the handle 32 of the container holder 30 against the opposite surface on the side of the housing. Container B is now in its previous position.

ES 2 294 594 T3

During the forward movement of the container carrier 30 and the container B, there is a coupling between the drive piece 10 and the transmission piece 20. The coupling is arranged in such a way that it is disconnected when the previous position of the container B is reached. .

This occurs due to the sizing of the yielding ring 21 and the design of the handle 22 configured as support for the ring 21. The handle 22 is oriented diagonally or in an arc, in the forward direction, from the widest posterior cross-section to the cut. narrower anterior cross section of transmission part 20.

The yielding ring 21 is round in cross section. In principle, the cross-sectional shape of the ring 21 and the path of the handle 22 should only be coordinated in such a way that the yielding ring 21 does not exceed the handle 22 already before reaching the position of the previous container, for which the coupling must transmit at least the reaction force that arises when advancing container B and the force necessary to inject the needle, and that the coupling does not lock but is released safely after reaching the position of the previous container. Coordination of the coupling is optimal when the disconnection is also jerk-free as much as possible.

If the coupling formed by the coupling means 12, 21 and 22, is disconnected, or also already during disconnection, the driver 10 which advances under the pressure of the actuating element 5 comes into contact with the piston rod and is thus coupled with the plunger, which is now pressed forward into contact with the driver 10 in the container B, so that the product is displaced and expelled through the needle N.

In order to compensate for the decrease, which accompanies the advance of the driver 10, of a force of the actuating element 5, the transmission part 20 can be conically widened on its inner lateral surface. The ring 12 would suffer a decreasing frictional force in the process of forward movement of the driver 10. For this further development of the invention, by means of a controlled damping of the actuating force, the elasticity of the ring 21 or of a pressure agent with the same effect would be advantageous.

As an alternative to this sliding friction force compensation control, the decrease in actuating force can also be compensated pneumatically. In the case of pneumatic compensation, the space surrounded by the lateral surfaces of the driver 10 and the transmission part 20 would be sealed as tightly as possible. The guide ring 18 mounted on the rear end of the transmission part 20 should be shaped as a sealing ring for the driver 10, which would even form a piston. Also the sliding surfaces formed between the inner side surface of the transmission part 20 and the opposite surface of the seal 11 can be configured as sealing surfaces. Thus, by advancing the driver 10, an increasing hollow space would be formed between the outer side surface of the driver 10 and the inner side surface of the transmission piece 20.

In the guide ring 18 formed as a seal, only one calibrated passage opening should then be provided, through which an agent, preferably air, could then pass into the otherwise closed hollow space. The vacuum generated in this hollow space by the forward movement of the driver would only be compensated in a delayed way, so that the advance speed of the driver 10 would remain constant throughout the entire travel path.

The spring 33 produces a damping and thus a delay in the forward movement of the container carrier 30 with the container B. However, the container carrier 30 and the container B travel a stretch of the path not obstructed by the spring 33, given that the handle 31 of the carrier of the container 30 only comes into contact with the spring 33 after traveling this section of the route. The forward movement along the remaining path to the previous position of the container is slowed down by the return force of the spring 33 which is weaker compared to the force of the actuating element 5. Thus, an introduction is achieved as desired. speed of the needle, with a subsequent slower thrust speed into the deeper tissue layers. The stop tabs 2a formed in the front bush of the housing 2 hold the holder of the container 30 in its rear position. However, under the pressure of the actuating element 5 and consequently of the container holder 30, the stop tabs 2a give way. By means of a holding handle 7 'which passes through the casing, it is brought back to its rear position, that is, the support and release sleeve 6 contained in a displaceable manner by the casing is tightened, and with it the driver 10. In in the rear position, a container B can be inserted again. The driver 10 and the sleeve 6 are correspondingly connected to each other.

Figure 2 shows a non-inventive embodiment of a self-injection device, also pencil-shaped, in longitudinal section, and in A-A cross section. In the case of this pencil, the actuating connection between the driver and the container, as well as between the driver and the piston is established and released only by a continuous connection. It presents, as another difference, a protective device for the needle, which covers the advanced needle after removing it from the tissue and, in this way, reduces the risk of injuries in subsequent handling.

The housing is also made up of a front casing bushing 2 and a rear casing bushing 3. The needle guard 1 is formed as a single piece, arranged in the front casing bushing 2. In the hollow cylindrical casing in turn, a container carrier 30 is housed, in which the container is carried, centered

ES 2 294 594 T3

B filled with the product to be administered, likewise the carrier is movable along the longitudinal central axis of the housing in both directions. In the forward movement for injecting the needle N, the container holder 30 is brought into a position of mutual contact of the anterior abutment surface 31 against a casing-side abutment, whereby the anterior position of the container B is defined. , that is, the injection depth of needle N. After the injection has been carried out, both casing bushings 2 and 3 are unscrewed, whereby the container B and the container holder 30 are released from the transmission part 20 and the container holder 30 is moved backwards to its position. rear position, the exit position, by the pressure of the return element 33 configured as return spring, by means of a rear abutment surface 31 against a casing-side abutment surface. In this rear position, a new container B can be inserted. After screwing in both housing bushings 2 and 3, the pencil in figure 2 is ready for the next injection.

As in the exemplary embodiment of FIG. 1, the driving piece 10 of the pencil of FIG. 2 acts, through a transmission piece 20, on the container; in the same way, the transmission part 20 could act on the carrier of the container 30, which would then drag the container B with it. The advancement of the piston K in the container B is carried out by the direct pressure of the seal 11 of the driver 10 on the piston rod that protrudes backwards from the container B, placed on the piston K from its rear side or configured in one piece with plunger K.

In FIG. 3 the driver 10, the transmission piece 20 and a guide agent 40 are represented correspondingly to their position in FIG. 2. In relation to the coupling and uncoupling of the driver 10 with and from the piece 20, always refer to the representation of FIG. 3.

The driver 10 is formed by a completely cylindrical base body with a seal 11 with expanded cross section. The actuating element 5, in turn, is formed as a compression spring and surrounds a part of the cylindrical shaft of the driver 10. In the pencil exit position, it is tensioned between the thickened seal 11 and the ribs 9, oriented from the rear bushing of the housing 3 in a radial direction inwards on the part of the cylindrical shaft. The drive piece 10 is held in its exit position by latches 15.

Multiple latches 15 are oriented, as an extension of the part of the cylindrical handle of the driver 10, away from the part of the cylindrical handle, and hold the ribs 9 oriented radially inwards from behind.

A rib or cam 13 protrudes from the outer side surface of the seal 11. With the cam 13 the drive part abuts a rear front surface 23 of the transmission part 20. The transmission part 20 is formed by a cylindrical bushing simple hollow, preferably a circular cylindrical bushing, from the outer side surface of which, in a rear area, a cam 25 protrudes radially outward. A release groove 24 is made on the inner radial surface of the transmission part 20 which extends in a longitudinal direction of the transmission part 20, leading to the front surface 23. The groove 24 is at least as large as the cam 13 of drive piece 10 can be received therein.

The transmission part 20 is arranged in an essentially hollow cylindrical bushing, preferably a circular cylindrical bushing, longitudinally displaceable and rotatable about the longitudinal axis. This bushing forms a guide agent 40 for the transmission part 20, in such a way that a displacement movement of the transmission part 20 in relation to the guide agent 40 is necessarily converted into a rotary movement around its longitudinal axis in relation to the guide agent 40, that is, the displacement movement is superimposed by a rotary movement. The guide agent 40 is configured as a separate sleeve, mounted in a fixed, non-rotatable or displaceable manner in the housing. In principle, it could also be designed in one piece with the housing, here with the rear housing sleeve 3, which, however, makes production more expensive.

The relative movement of the transmission part 20 in relation to the guide agent 40 and the drive part 10 guided in a straight line within the housing, securing it against rotation, is caused by a slide guide configured between the transmission part 20 and guide agent 40.

In the configuration of the slide guide, a guide groove 41 for the cam 25 has been made in the inner lateral surface of the guide agent 40, opposite the cam 25 of the transmission part 20. The guide groove 41 has a straight rear groove segment 42 and a second groove segment that continues the first in the form of an arc 43, optionally terminated diagonally, that is, the second groove segment 43 has a component transverse to the forward direction of the transmission part 20. In the starting position, the cam 25 is located in the slot segment 42.

An activation mechanism has an outer sleeve 4, an activation button 7 and a return spring 8. The outer sleeve 4 surrounds the rear area of ​​the rear sleeve of the housing 3 and is movable in both directions on the outer side surface of the sleeve. rear of the casing 3 along its longitudinal axis. The activation button 7 is inserted into a central opening in the rear front surface of the outer sleeve 4. It passes through this opening with an inner sleeve that extends almost to the latches 15 of the driver 10.

ES 2 294 594 T3

For the injection, the pencil is pressed against the skin, so that a protective sleeve for the needle 50, movable in the anterior area in both directions in the longitudinal direction, is inserted into the anterior sleeve of the casing 2, below the protector of the needle. needle 1, against the pressure of a return element 51 configured as a return spring. In this state, needle N is still behind the leading edge, shaped by the leading ends of needle guard 1 and needle guard sleeve 50.

The injection of the needle N and the expulsion of the product are carried out by pressing the activation button 7 in the longitudinal direction of the pencil on the driver 10 or its latches 15. The inner sleeve of the activation button 7, in turn, overhangs , to the rear ends of the latches 15, which are thus brought together by elastically arching radially inward, whereby the ratchet connection with the ribs 9 on the housing side is released.

The pressure of the actuating element 5 is transmitted, from the released drive part 10 which presses with its cam 13 against the rear front surface 23 of the transmission part 20, to the transmission part 20, which, in turn, presses with its front front surface against the rear flange surface of container B. With the front front surface of the same flange, the container B presses against the container carrier 30, which, in turn, presses against a locking sleeve 60 that is not displaceable relative to the housing by means of a return element 33. However, the pressure force of the return element 33 is comparatively low relative to that of the actuating element 5, so that under the pressure of the actuating element 5, the drive part 10, the transmission part 20 and the container carrier 30 are moved together with container B in the housing along the longitudinal axis of the housing.

In turn, the cam 25 of the transmission part 20 enters its guide slot 41. As soon as the cam 25 enters its movement in the second segment of the slot 43, the transmission part 20 is forced to rotate on its own. shaft, because of the transverse components of the second segment of the groove 43. The path of the guide groove 41 is selected in such a way that the release groove 24 made in the transmission part 20 that opens into the front surface 23, is located superimposed on the cam 13, due to the relative forced movement in relation to to the casing and in relation to the driver 10.

As soon as the release groove 24 covers the cam 13, the drive piece 10 is disengaged from the transmission piece 20. The path of the guide groove 41 is selected in such a way that the overlap is re-established as soon as the carrier of the container 30 is in contact with the front abutment surface 31 in the housing and thus the container B is located in its previous position. With disengagement, that is, release, the drive part 10 can continue its forward movement relative to the transmission part 20 under the pressure of the actuating element 5. It in turn presses against the piston rod, so that the plunger K is pushed forward in the container B, in direct contact with the driver 10, until the product is expelled.

The injection of the needle N is determined, as desired, by the path of the guide groove 41. The needle N first penetrates very quickly, since in a first part of the advance movement of the transmission part, it advances in a straight line in the forward direction and therefore no resistance is opposed to the forward movement of the transmission part 20. The penetration speed slows down when advancing, since the guide groove 41 at that point also runs perpendicular to the direction of advance, in the exemplary embodiment, in a helical shape, and therefore the transmission part suffers, when moving, the effect of a frictional force dependent on the inclination of the guide groove segment 43. Additionally the speed with which the needle is injected is reduced by the increasing return force of the return element 33.

Figures 4 and 5 show, together with Figure 2, the mode of action of the needle protection device that prevents the needle N from protruding freely from the housing after removing it from the fabric and may break or cause injuries in the event of negligent handling. The essential feature of the needle guard device is that for injection purposes, the needle guard sleeve 50 movable relative to the housing is locked in a needle guard position after removal of the needle, so that cannot be moved towards the inside of the casing, an external overlap of the casing could also be envisaged.

Figure 4 shows the front part of the pencil of Figure 2 in the anterior position of the container B. The protective sleeve of the needle 50 was pressed against the force of the return element 51 in its position of posterior displacement in relation to the sleeve of the needle. the housing 2. The needle N protrudes above the housing and needle guard sleeve 50 by the desired distance.

The needle guard sleeve 50 has a rear abutment surface and an anterior abutment surface, which limit the travel path of the needle guard sleeve 50 relative to the front casing sleeve 2 in the forward direction and against the forward direction. As the needle guard sleeve 50 moves in both directions, it passes through the locking sleeve 60, which has at its front end a hook 62 projecting outwardly in a diagonal or curved manner. In an area of ​​internal lateral surfaces with which it slides over the hook 62, the needle guard sleeve 50 exhibits, approximately corresponding to the length of its maximum travel path, a slightly expanded internal diameter. A passage area 52 between this anterior expanded cross-section towards the inner cross-section attached to it is chamfered so that the needle guard sleeve 50 can slide under the pressure of the return element 51 to behind the passage area 52, past for him

ES 2 294 594 T3 hook 62. The needle guard sleeve 50 is provided, behind the passage area 52, with an intermediate area with longitudinal grooves 53, the front front surfaces 54 of which each form a stop surface for a hook 62, as best recognized in figure 5.

The locking sleeve 60 develops by forming multiple elastically yielding tabs 61, evenly distributed around the perimeter of the sleeve, at the free front ends of which the hooks 62 are configured. The container carrier 30, in turn, also develops forming a tab 34 at its free front end. As the container carrier 30 is advanced, its tabs 34 are positioned below the tabs 61 of the locking sleeve 60. In this way, each of the tabs 61 is held radially inward and can no longer be bowed radially inward in the former position of the container. The tabs 61 are not only supported by the tabs 34, but further radially outwardly pressed. The tabs 34 are configured comparatively rigid relative to the tabs 61, or can be assumed to be rigid at first convergence relative to these tabs 61.

After removing the needle, the needle guard sleeve 50 is pushed forward again by the return element 51. Through the diagonal travel of the surface 52 and / or the corresponding diagonal travel of the hook 62, it passes this hook 62, whose termination The point is also elastically yielding. As soon as the needle guard sleeve 50 has been pushed so far forward that, viewed in the forward direction, its abutment surface 54 is positioned in front of the hook 62, it is blocked against a backward movement by the hook 62 which makes abutment against abutment surface 54. Hook 62 and needle guard sleeve 50 are in mutual contact through abutment surfaces perpendicular to the direction of advancement. In the safety position shown in figure 5, after injection the needle N is protected by the protective cap of the needle 50.

In this way, the container holder 30 is also used as a movable support for the elastic element 62 and fulfills, according to the invention, the double function of carrying the container and blocking the needle holder sleeve 50. The protective device for the needle does not presuppose the configuration according to the invention of the self-injection device, but is used with particular preference in combination with it. It is also advantageously applicable in self-injection devices of this type and even without modifications also in injection devices in which the injection of the needle is carried out by manual displacement of the container relative to the housing.

Figure 6 shows, in a longitudinal section, and furthermore, in a plan view, a self-injection pencil, in which the coupling of the driver 10 with the container B as well as with the piston K, is based on a continuous and drag joint. The coupling is comparable, in its operation, to that of the pencil in figure 1. From now on, reference is always made to the cross sections included in the plan view and detail X.

In the container B of the pencil in Figure 6, it is a so-called double-chamber ampoule, in which two product components, in two chambers arranged one behind the other, separated from each other in the state of distribution of container B by an anterior plunger K1, which are just mixed with each other when advancing the posterior plunger K2 until it stops with the anterior plunger K1. A powdered active agent is generally present in the front chamber in the dispensing state, while a carrier liquid is retained in the chamber formed between the two pistons K1 and K2.

In the state represented in FIG. 6, both components are already completely mixed in the anterior chamber located between the piston K1 and the container outlet, due to the displacement of the posterior piston K2 until it stops with the anterior piston K1. The casing again has a front and a rear casing bushing 2 and 3, fixedly connected, for example by screwing or shoring. A hinged lid is inserted into the rear housing bushing 3. The front housing bushing 1 is extended by a needle guard 1 and a needle guard cap 50 ', which is movable back against a return force, for injection of needle N, and, after injection , return to the forward position.

Container B is inserted into a container holder 30 until it stops and is held centrally. The container carrier 30 is movable against the force of the return element 33 in the housing.

The forward movement of the rear piston K2 is produced by assembling the front sleeve of the casing 2 and the rear sleeve of the casing 3. For this purpose, a fixed, non-rotating way has been received in the rear casing sleeve 3, a mixing piece 20 designed as a hollow body. The mixing piece 20 has a front area of ​​the bushing with an outside diameter smaller than the inside diameter of the container B, and a rear area widened compared to this front area. A passage between these two areas of the sleeve is configured as a handle 28 projecting radially from the front area of ​​the sleeve. Handle 28 is circularly shaped; but it can also be configured by at least one radially projecting bridge. With its rear front surface, the mixing piece 20 touches bridges 9 radially inwardly directed from the rear casing bush 3, which can also be designed as circular walls. When the device is assembled, that is to say when both casing bushings 2 and 3 are screwed in, the mixing piece 20, housed in the rear casing bush 3 and thereby secured against displacement, is inserted into the open container B from behind and pushed forward into it. In turn, it pushes the rear piston K2 forward, towards the front piston K1, until the rear piston K2 reaches the position shown in figure 1. In this position of the pistons K1 and K2, the tightening of the housing bushes 2 and 3 is also completed.

ES 2 294 594 T3

In the rear sleeve of the housing 3 there is the actuating device which includes the actuating element 5 in the form of a compression spring and the rod-shaped driver 10, which is guided in a straight line in the housing. The actuating element 5 is tensioned between the bridges 9 and a surface of the circular handle of the driver 20, facing the bridges 9, relative to the direction of advance.

The driver 10 is housed around a central longitudinal axis of the casing, which coincides with its own central longitudinal axis, in a rotational manner between two rotational positions. To rotate the driver 20, a metering sleeve D is provided which extends the housing. In its rear area, facing the inside of the dosing sleeve D, the driver 10 has guide grooves extending in the direction of advance, in which a guide sleeve 6a facing the inside of the hinged lid 4 engages, rotatable but secured against displacement relative to the hinged lid 4, and an indicator sleeve 8 rotatably housed by the housing but secured against displacement. The guide bushing 6a is connected and secured against rotation with the dosing bushing D, as can best be seen in section H-H. The guide bushing 6a serves to transmit the rotational movement of the dosing bushing D to the driver. 10. The indicator sleeve 8, secured against rotation with the driver 10, serves to indicate the rotational position of the driver 10 and thus to indicate the amount of dose set. For this purpose, it is provided with markings on its outer perimeter, in the exemplary embodiment, with two markings for each of the two rotation positions of the driver 10. The markings can be read through an opening in the housing. . The indicator sleeve 8 and also the guide sleeve 6a serve together with the mixing piece 20 as a straight-line guide for the driver 10.

The driver 10 is held by a locking and activation mechanism in the rear exit position shown. This locking and activating mechanism has an activating means 7a in the form of an activating button, which acts on a locking means 7b, perpendicular to the direction of advance of the driver. The construction and mode of action of the locking and activation mechanics can best be recognized by joint observation of the longitudinal section and the F-F cross section.

The locking means 7b is formed by a hollow body with a passage opening through which the driver 10 protrudes. In order to guide it in a straight line, the locking means 7b is guided between two straight bridges of the housing in the direction perpendicular to the direction of longitudinal advance of the driver 10. Oriented respectively to these two bridges of the housing, the hollow body of the locking means 7b has correspondingly straight outer surfaces. The passage opening of the blocking means 7b is greater than the outer diameter of the driver

10. By the pressure exerted on the activating means 7a the blocking means 7b is displaced perpendicular to the direction of advance of the driver 10, against the force of a return element 7c configured as a compression spring. In the locking position the driver 10 touches, with a handle 29 configured by a thickening, against a rear front surface of the locking means 7b. By a perpendicular movement of the locking means 7b this stop is canceled. The driver 10 is released from the blocking agent 7b and can be moved forward in the longitudinal direction under the pressure of the actuator 5.

A safety device ensures that the activating agent 7a is only actuated, and thus the driver 10 is released, when a container B has been placed in the housing. The safety device comprises a full cycle control body 70 and a compression spring 19. The full cycle control body 70 has a central bushing area, from which two bridges 70a protrude forward in the longitudinal direction (cut E - E). Both bridges 70a pass through two correspondingly formed grooves in the handle 28 of the mixing piece 10 and touch the rear edge of the container B. A third bridge 70b protrudes from the central bushing area of ​​the total cycle control body 70 in a longitudinal direction towards the rear. . This third bridge 70b crosses the activating means 7a, as can be better recognized in the joint observation of the longitudinal section with both sections F-F and G-G.

At the level of the activator means 7a, that is, in the area that passes through the activator means 7a, the third bridge 70b of the total cycle control body 70 has a longitudinal section. In this longitudinal section, a rib 7d of the activator means 7a that protrudes radially inward engages when the activator means 7a is actuated, when the groove of the total cycle control body 70 is at the same height as the inner rib 7d of the activator means. 7a. Viewed in the longitudinal direction, behind the area with the groove, the third bridge 70b is formed, again as a closed bridge. Between the casing-side bridge 9 and an inner side surface handle protruding inwardly from the central area of ​​the full cycle control body bushing 70, the compression spring 19 is tensioned. If a container B is placed, then the total cycle control body 70 presses with its front bridges 70a against the rear edge of the container B and is thus held in the position represented in the longitudinal section of Figure 1, in the which the inner rib 7d of the activating means 7a can enter the groove of the full cycle control body 70 and move the locking means 7b perpendicularly. In case a container has not been inserted, the total cycle control body 70 is moved forward by the compression spring 19, in the annular passage now free for this cause, until the central area of ​​the sleeve of the body of total cycle control 70 touches against handle 28 of mixer 10. In this locking position of the full cycle control body 70, the rear closed area of ​​the third bridge 70b is located in front of the rib 7d of the activating means 7a. A perpendicular movement of the activating means 7a is not possible in this case. The actuating device is blocked in that case.

Between the mixing piece 20 and the driver 10 that passes through the mixing piece 20 there is a drive coupling, which causes the mixing piece 20 to be driven by the driver 10 in a movement

ES 2 294 594 T3 for advancing the driver 10, that is, it is itself pushed forward relative to the housing. The coupling is established based on a continuous and drag connection in the front area of ​​the mixing piece 20, which resembles the coupling of the exemplary embodiment of Figure 1. The mixing piece 20 adopts in its dual function the function of a single piece. transmission, and is hereinafter called mixing and transmission part 20.

Unlike the coupling in the exemplary embodiment of figure 1, in that of figure 6 the elastic deformation ring 21 is housed in a groove formed in the inner lateral surface of the mixing and transmission part 20, and correspondingly, the driver 10 has, for the ring 21, only one contact surface 17 that causes the drag of the mixing and transmission piece 20. The contact surface 17 forms a first coupling means, a contact surface 27 formed by the groove of the mixing and contact piece 20 is a second, and the ring 21 is a third coupling means.

The mixing and transmission part 20 and the driver 10 form a dosing device in an area arranged inside a container B. The mixing and transmission part 20 is provided, for this, with a notch in a lateral surface area located behind the first coupling means 17. The notch has two grooves 25 and 26 extending in the direction of advance, arranged side by side, angularly offset in parallel. Slots 25 and 26 have different lengths in the forward direction. The shorter groove 25 is formed as a blind groove on the side surface, and the longer groove 26 is limited in the forward direction by the rear bridge of the groove for the third coupling means 21. At their rear ends, the grooves 25 and 26 lead to the same groove in relation to the advance device in a widening of the notch, as can be better recognized in the joint observation of the longitudinal cut with the cuts CC, D- D and E- E. The broadening of the notch reaches to the rear front surface of the front area of ​​the mixing and transmission part bushing 20. The side walls of the widening, facing each other and leading to one another, are extended respectively by one of the two grooves 25 and 26 in the direction of advance.

The driver 10 is provided with a cam 16 that protrudes radially. In the output state of the injection device, the cam engages in the widening of the notch of the mixing and transmission piece 20. The notch with both grooves 25 and 26 forms a first dosing means, and the cam 16 a second means dosing device of the dosing device.

In a first dosing position the cam 16 is located, aligned with the slot 25, in the first side wall of the enlargement that extends in the direction of advance, and in the second dosing position, the cam 16 is located, aligned with the slot 26, in the second side wall of the flare that extends in the direction of advancement of the notch. Between these two dosing positions, the driver 10 is rotatable around its longitudinal axis in both directions, in the exit position of the injection device. Both side walls of the wide slot define both rotation and dosing positions of the driver 10, and the lengths of both narrow slots 25 and 26 define the amount of expellable active substance solution in one injection.

The widening of the notch in the mixing and transmission piece 20 could be extended almost to the end of the short groove 25 in the direction of advance, such that the notch would have, in the direction of advance, a simple stepped development.

To carry out a self-injection, the self-injection device is supported on a tissue surface, especially on human skin, with the anterior needle guard sleeve 50 ', movable rearwardly in relation to the housing or the anterior needle guard. 1. By the pressure against the fabric surface the needle guard sleeve 50 'is moved rearwardly, to a posterior position relative to the housing. The injection needle N, fixedly arranged at the outlet of the container B and oriented in the forward direction, is first still surrounded by the needle guard 1 and the needle guard sleeve 50 'which covers it beyond its anterior tip, and therefore does not yet touch the surface of the tissue.

For actuation, i.e. to inject the needle and eject the active substance solution, the user presses the activating agent 7a inwards in a radial direction, after having brought the driver 10 into the desired rotary or dosing position by means of the dosing sleeve D. By inward pressure, the locking means 7b is moved under the stop handle 29 and the driver 10 is released. Under the pressure of the actuating element 5, the driver 10 moves, and through the coupling also the mixing and transmission piece 20 moves, both in relation to the housing. The continuous and drag connection between the driver 10 and the mixing and transmission piece 20, is strong enough to cause the dragging of the mixing and transmission piece 10, which by its side, pressing by means of its handle 28 against the container carrier 30, advances these in relation to the casing, against the force of the return element 33 to a previous position, defined by a stop 31a on the casing side.

In the anterior position of the container carrier 30 or of the container B, the coupling releases the drive connection between the drive part 10 and the mixing and transmission part 20. Under the pressure of the drive element 5 the yielding ring 21 still remains. It is pressed by the fixing of the mixing and transmission part 20 and pushed over the diagonal handle 17. The driver 10 continues to advance in relation to the mixing and transmission part 20 and also pushes both pistons K1 and K2 in the container in the direction of the outlet of the

ES 2 294 594 T3 container. The active substance solution is expelled through needle N injected into the tissue, located in the anterior position of container B.

The forward movement of the driver 20 is limited in the first dosing position by the front end of the slot 25. In the first dosing position, the ejection is finished when the cam 16 hits against the wall of this slot, extending in the direction of the circumference.

After removing needle N the injection device is ready for a second injection. For this, it is only necessary to first move the drive piece 10 back relative to the mixing and transmission piece 20, in the opposite direction to the advance. At the front end, the driver 10 has a seal 11 in the form of a flange-like flare. When expelling solution of active substances, the driver 10 presses with the seal 11 against the rear plunger K2, and, when retracted, the surface of the circular rear handle of the seal 11 touches against the projecting bridge from the inner side surface of the piece mixing and transmission device 20, which forms the front wall of the reception slot for the third coupling means 21. As the drive piece 10 continues to move back, the mixing and transmission piece 20 is dragged, that is, it is also pushed back to its rear position shown in figure 1. The container carrier 30 and the container B housed in it B they accompany the movement of the mixing and transmission piece 20 under pressure from the return element 33. The return force of the return element 33 is comparatively less than the actuation force of the actuation element 5, so that it does not interfere with the advancement of the container B in order to inject the needle N.

For the next injection, the driver 10 is rotated to its second dosing position, in which the cam 16 is aligned with the slot 26. In this position the driver 10 can be advanced both in relation to the mixing piece. and transmission 20, that the remaining quantity of the active substance solution still in the container is expelled when the actuator is actuated, that is, when the actuator is actuated.

7. The forward movement is limited by a circular bridge that forms the rear wall of the receiving slot for the third coupling means 21.