WO2001036028A1

WO2001036028A1 - Injection device

Info

Publication number: WO2001036028A1
Application number: PCT/DE2000/003953
Authority: WO
Inventors: Andy RÖSCH
Original assignee: Rösch Ag Medizintechnik
Priority date: 1999-11-16
Filing date: 2000-11-14
Publication date: 2001-05-25
Also published as: DE20006986U1; JP2003513762A; TW496747B; CN1390146A; DE10083482D2; EP1229952A1; DE19955201A1; AU2502101A; AR030035A1

Abstract

The inventive injection device for injecting a liquid into a subcutaneous tissue by means of a pressurized jet comprises a base body (1) that carries a tripping device (21). Said base body is linked by means of a detent connection (12) with an ampoule-body (2) that receives the liquid. A spring element (5) that generates a force for displacing a thrust piece (4) and a retaining element (6) retaining the thrust piece (4) in an initial position are designed for a single injection. The base body (1) is produced from plastic by transfer molding, thereby allowing an especially inexpensive large-scale manufacture of the injection device.

Description

description

injection device

The invention relates to an injection device for injecting a liquid, in particular a medicament, into a subcutaneous tissue, with an ampoule body, with a chamber arranged in the ampoule body and having an opening, with an ampoule piston for reducing the volume of the chamber, with a movable one Spring element biased pressure piece against a holding element and with a trigger for moving the holding element from a first position holding the pressure piece into a second position releasing the movement of the pressure piece and with a basic body for holding the trigger and for guiding the pressure piece in the second Position holding element against an end of the ampoule piston facing away from the chamber.

Such an injection device is known from WO 98/15307. In this injection device, the ampoule body having the chamber is screwed into the base body. The basic body has a bearing for the trigger made in one piece with the holding element. When the trigger is pressed, the holding element swings out of the range of movement of the pressure piece. The force of the spring then moves the pressure piece against the end of the ampoule piston protruding from the chamber. In its position held by the holding element, the pressure ^{piece is} beabstan ^¬ _d et from the free end of the ampoule bulb. This ensures that when the trigger is actuated, the pressure piece is provided with an intended pulse hits the free end of the ampoule bulb. The liquid in the chamber then exits the opening as a high-pressure jet. When the opening is placed on the skin, for example of a human being, the liquid passes through the skin into the subcutaneous tissue. A needle penetrating the skin for introducing a medicament into the subcutaneous tissue is therefore not necessary. The depth of penetration of the liquid and the shape of the high-pressure jet can be measured by the shape and dimensions of the opening in relation to the dimensions of the chamber and by the characteristic curve of the spring. In addition, a damping element is arranged in the basic body, which dampens the impact of the pressure piece at the end of the movement of the ampoule piston.

After an injection, the ampoule body is separated from the base body together with the ampoule bulb. The pressure piece, the trigger and the holding element are moved back to their starting positions by means of a charging station. Then a new or a newly filled ampoule body can be screwed onto the base body. The injection device is thus prepared for a new injection.

A disadvantage of the known injection device is that it is very expensive to manufacture. For example, the basic body is made of easy-to-clean stainless steel. The spring member is sized to a thousand ermudungs- free tension and relaxation for several Add _j ections and thus made of a very intensive kostenin ^¬ material. Furthermore requires Hal ^¬ teelement to slide along in the drawing lots to the pressure stucco a very high material strength and sliding doughs ^¬ shaft, to enable the repeated use of the Injektionsein ^¬ direction to avoid the pressure stucco accidental lots. Furthermore, an injection device has become known from practice, in which the force required for generating the pressure jet is applied by a gas filling. This injection device is f _o r single use designed and therefore requires no after use aufwandige cleaning. However, a chamber receiving the intended gas filling is very difficult to manufacture. This injection device is therefore very expensive to manufacture. Furthermore, a time-dependent escape of the gas from the gas filling and thus a reduction in pressure cannot be avoided.

The invention is based on the problem of an in _j ektionseinrichtung to make the aforementioned type so that it is particularly inexpensive to manufacture.

This problem is solved according to the invention in that the strength of the spring element and the holding element and / or the base body is dimensioned for use for a single injection and means are provided for preventing further injections after the first use.

This design allows particularly inexpensive materials to be used for the individual components of the injection device according to the invention. Material fatigue of the spring element generally only begins after a large number of injections and, thanks to the invention, does not lead to a change in the intensity of the high-pressure jet. The holding element can also be made of a particularly inexpensive material with a low strength. Here, a damage of the retaining element during actuation of the Auslosers, provided at least at the f _o r single-use injection device, inconsequential. Furthermore, the injection device according to the invention does not require a damping element. ment to limit the movement of the pressure piece. As a result, the injection device according to the invention is particularly cost-effective. A risk to people through repeated use of the injection device according to the invention, which is dimensioned for single use, is also reliably avoided. The prevention of further injections after the first use can optionally be designed in such a way that a component is destroyed during the first use or that the injection device according to the invention cannot be prepared for a new use without detailed design knowledge and tools. Furthermore, the injection device according to the invention can be delivered in the tensioned state, so that no cost-intensive tensioning device is required.

According to an advantageous development of the invention, the means for preventing further injections after the first use are structurally particularly simple if the ampoule body is inseparably connected to the base body after assembly.

For further simplification of the means for preventing further injections after the first use, it contributes in accordance with another advantageous development of the invention, when the spring element is held THE RESIDENCE _ä after assembly ACCESSIBLE between the Ampullenkorper and the base body.

To further reduce the cost of the inventive In _j ektionseinrichtung it carries out at when the base body ^¬ is made of plastic. Since cleaning of the base body at least in the dung need intended for single Ge ^¬ injection device thanks to the OF INVENTION ^¬ is not required, the base body can have almost any surface roughness. To further reduce the costs of the injection device according to the invention in the case of large numbers of pieces, it contributes if the basic body made of plastic is manufactured by injection molding.

As with the injection device known from WO 98/15307, the trigger can be pivoted. According to another advantageous development of the invention, the mounting can be easily installed if the mounting of the trigger has a bearing shell that is open on one side.

According to another advantageous development of the invention, storage of the trigger is easily avoided if the trigger is held axially displaceably in a guide of the base body transverse to the direction of movement of the pressure piece. For installation, the trigger can simply be inserted into the guide. This assembly can also be carried out immediately before the injection, so that a securing element to avoid unintentional actuation of the trigger is not required. Such guides can be easily provided in the manufacture of the base body by injection molding.

According to another advantageous development of the invention, the trigger is structurally particularly simple if the trigger has a pressure plate which can be displaced perpendicularly to the direction of movement of the pressure piece and an arm which surrounds the basic body and is arranged in the guide.

The holding element could, for example, be pivotally mounted on the base body and deflected by the arm of the trigger. The injection device according to the invention However, ricntung requires particularly few components if the holding element is fastened to the end of the trigger arm facing away from the pressure plate and penetrates a wall of the base body in the region of an opening.

As in the injection device known from WO 98/15307, the ampoule body could be screwed to the base body. To simplify the assembly of the injection device according to the invention, however, it helps if the base body has a snap-in connection for holding an ampoule body having the chamber. In this way, for example, the ampoule body can only be connected to the base body immediately before the injection. This significantly reduces the risk of the liquid escaping from the ampoule body if the trigger is accidentally actuated.

According to another advantageous development of the invention, the latching connection between the base body and the ampoule body is structurally particularly simple if the base body has latching hooks on its end facing the ampoule body for engaging behind a side of a collar of the ampoule body facing away from the spring element. Another advantage of this design is that of the known Ampullenkorper In _j ektionseinrichtung can be used in the inventive shaped injection device, since the Federal Government serves as a stop in the conventional injection device. This leads to a further reduction in the manufacturing costs of the injection device according to the invention. By suitable choice of the snap hooks also a Tren ^¬ let voltage of Ampullenkorpers of the base body after its assembly easily prevent.

A separation of the ampoule body from the base body can be done according to another advantageous development. Avoid fertilization of the invention reliably when em locking ring engages around the outside of the locking hook in the assembled state of the ampoule body. This prevents the catch hook from bending away from the ampoule body.

The disassembly of the locking ring and thus the possible separation of the ampoule body from the base body is reliably prevented according to another advantageous development of the invention if the locking ring has at least one radially inward-pointing hook for its positive connection with the ampoule body or the base body in the over the locking hook located position.

To further simplify the assembly of the injection device according to the invention, it helps if the latching hooks on the end of the base body facing away from the spring element have emptying slopes forming a funnel.

The use of the injection device according to the invention is particularly convenient if the base body has a stop intended to limit the axial mobility of the ampoule body in the direction pointing towards the pressure piece.

According to another advantageous development of the invention, a particularly precise and therefore cost-intensive alignment of the ampoule body with respect to the pressure piece can be easily avoided if the base body has a guide for a central area of the ampoule bulb.

As in the injection device known from WO 98/15307, the spring element could be adjusted at its end opposite the pressure piece on an adjustable Trim the screw. To further reduce the manufacturing costs of the injection device according to the invention, however, a cap attached to the base body and supporting the spring element at the end opposite the pressure piece contributes. Like the basic body, the cap can be made of plastic by injection molding.

To further simplify the assembly of the injection device according to the invention, it helps if the connection of the cap to the base body has a snap-in connection.

The number of components of the injection device according to the invention can be kept particularly low if the basic body for receiving the spring element and the pressure piece is designed in the shape of a pot.

The injection device according to the invention can be completely preassembled with trigger and ampoule body. Here, a securing device to prevent unintentional actuation of the trigger is structurally particularly simple if the securing element holding the trigger is held in the position blocking the movement of the trigger with an intended force. In the simplest case, the securing element can be designed as a tear-off part and can be thrown away after being pulled out of the gap.

To further reduce the number of components to be assembled in the injection device according to the invention, it helps if the locking ring is displaceably guided on the base body and the locking element is arranged on the locking ring. It contributes to a further reduction in the production costs of the injection device according to the invention if the pressure piece is made of steel by the extrusion process

The invention permits numerous embodiments. To further clarify its basic principle, two of them are shown in the drawing and are described below. This shows in

1 shows a longitudinal section through an injection device according to the invention before an injection,

2 shows a sectional view through the injection device from FIG. 1 along the line II-II,

3 shows a longitudinal section through the injection device according to the invention from FIG. 1 after an injection,

4 shows a longitudinal section through a further embodiment of the injection device according to the invention,

5 shows the injection device from FIG. 4 after the first use.

1 shows a fully made of plastic in _j ektionseinrichtung with a basic body 1 and a locked with the base body 1 Ampullenkorper 2. If the base body 1 is a leadership 3 for em langsverschieb- pending printing stucco 4. The pressure stucco 4 is by a trained as a compression spring spring element 5 against a Haitee element 6 biased. The spring element 5 is supported on a cap 8 connected to the basic body 1 via a snap-in connection 7. The ampoule body 2 has a chamber 9 with an opening 10 for receiving a liquid, in particular a medicament, which is to be injected into em subcutaneous tissue. The chamber 9 can be reduced in size by an ampoule piston 11 which can be moved slowly relative to the ampoule body 2. With its end facing away from the chamber 9, the ampoule bulb 11 is at a distance from the pressure piece 4. The connection of the ampoule body 2 to the base body 1 has a latching connection 12 with latching hooks 13, 14 arranged on the base body 1 and a stop 15. The latching hooks 13, 14 engage behind a collar 16 of the ampoule body 2 and hold the latter on the stop 15. Furthermore, the latching hooks 13, 14 have an introduction collar 17, 18 forming a funnel 19 arranged at one end of the base body 1 with the base body 1, the ampoule body 2 with the collar 16 can be impressed into the end of the base body 1 which has the latching hooks 13, 14. The locking hooks 13, 14 spring radially outwards and engage behind the collar 16 as soon as it comes against the stop 15. FIG. 1 further shows that the basic body 1 has a guide 20 for the ampoule piston 11.

The holding element 6 holding the pressure piece 4 in its drawn position is connected to a trigger 21. The trigger 21 has an arm 23 connected to a pressure plate 22. The pressure plate 22 and the Halteelemen _t 6 are arranged on opposite side of the base body 1 so that upon displacement of the pressure plate 22 in the direction of the base body 1, the holding element is moved out 6 from the leadership 3 for the pressure stucco. 4 An inadvertent movement of the pressure plate 22 is prevented by a securing element 24. prevents. The securing element 2 ^ is clamped in a gap 25 between the pressure plate 22 and the base body 1 and has a tension strip 26. The securing element 24 can be gripped on the pull strip 26 and pulled out of the gap 25.

For the injection of the liquid in the chamber 9 with subcutaneous tissue, the securing element 24 is first removed and the injection device with the opening 10 of the ampoule body 2 is printed on the skin. Subsequently, the holding element 6 is moved by pressing the pressure plate 22 from its drawn-in first position into a second position outside the guide 3 of the pressure piece 4, and thus the movement of the pressure piece 4 is released. The pressure piece 4 is accelerated by the force of the spring element 5 against the end of the ampoule piston 11 facing away from the chamber 9 and presses it into the chamber 9. The liquid in the chamber 9 passes through the opening 10 as a high-pressure jet. The intensity of the high-pressure jet, and thus the depth of penetration of the liquid into the subcutaneous tissue, can be determined by the dimensions of the opening 10 in relation to the dimensions of the chamber 9 and by Set the characteristic curve of the spring element 5.

Figure 2 shows the injection device of figure 1 m a sectional view taken along II - II of Figure 1. It can be seen that the shutter button 21 a total of two, _j in each case in Guided Tours 27, 28 of the base body 1 arranged arms 23, has 29th The holding member 6 penetrates the base body 1 in an opening 30. To assemble the Auslosers 21 with the base body 1, for example, the arms 23 are pushed over the parent compound 1 29 bent outwardly from one end and _above. The arms 23, 29 then rest in the guides 27, 28 em. Selbstverstand- - ι;

On loan, the trigger 21 or the basic body 1 can also be designed in two parts and glued or clipped together during assembly.

Figure 3 shows the injection device of Figure 1 after use. It can be seen here that the holding element 6 is in the second position, which releases the movement of the pressure piece 4. The pressure piece 4 lies against a stop 31 of the base body 1. The ampoule bulb 11 is pushed against the end of the ampoule body 2 which has the opening 10. Since the latching connection 7 of the cap 8 with the base body 1 is not accessible from the outside, the pressure piece 4 and the spring element 5 in the base body 1 are kept virtually inaccessible from the outside. Furthermore, it is very difficult to separate the ampoule body 2 from the base body 1, since the latching hooks 13, 14 point radially inwards. Since the base body 1 is made of plastic, a violent separation of the ampoule body 2 or the cap 8 from the base body 1 also leads to damage to the latching connections 7, 12. This largely prevents the spring element 5 from being re-tensioned and the ampoule body 2 being replaced.

FIG. 4 shows an injection device with a pot-shaped base body 32 and an ampoule body 33 which is latched to the base body 32. The base body 32 receives pressure piece 35 preloaded from a spring element 34 in the direction of the ampoule body 33 and is in one piece with a bearing shell 36 which is open on one side manufactured. In the bearing shell 36, a trigger 37 is pivotally mounted with a holding element 38 supporting the pressure piece 35. FIG. 4 also shows that a retaining ring 39 is axially displaceably guided on the base body 32. E securing element 40, which is made in one piece with the locking ring 39, supports in .. J -

the drawn position αen trigger 3 ⁷ ate. This prevents the trigger 37 from pivoting and thus prevents movement of the pressure piece 35 by the force of the spring element 34. As with the injection device according to FIGS. 1 to 3, the base body 32 has latching hooks 41 with a stop 43 spaced apart from them for holding a collar 44 of the ampoule body 33. The position of the locking ring 39 shown in FIG. 4 indicates the position in which the injection device can be transported. For this purpose, the securing ring 39 has a radially inwardly pointing hook 45, with which it penetrates into a correspondingly designed recess 46 of the base body 32. The hook 45 can be moved out of the recess 46 with a force that is to be exerted on the locking ring 39 in the axial direction.

To use the injection device, the locking ring 39 is first pushed away from the trigger 37 so that the locking element 40 comes out of the range of motion of the trigger 37. The trigger 37 can then be depressed, so that the pressure piece 35 is moved by the force of the spring element 34 against an ampoule piston 47 of the ampoule body 33. This position is shown in Figure 5. The locking ring 39 is here in the position pushed over the locking hooks 41 of the base body 32 and prevents it from bending open. The hook 45 arranged on the locking ring 39 snaps between two locking hooks 41 of the base body 32 and thus prevents the locking ring 39 from being pushed back. E Pushing the locking ring 39 over the ampoule body 32 is made possible by a further hook 48 which rests on the collar 44 of the ampoule body 33 the locking ring 39 prevented. The Ampoule body 33 is therefore inseparably connected to the base body 32. Furthermore, the pressure piece 35 and the spring element 34 are kept inaccessible between the ampoule body 33 and the base body 32. The injection device can therefore no longer be used again.

For ampoule bodies 33 with different volumes, the injection device can be adapted by using appropriately designed pressure pieces 35 and spring elements 34. The basic body 32, the trigger 37 and the locking ring 39 can be used unchanged in all of the ampule bodies 33 which are common in medicine. As a result, the basic body 32, the trigger 37 and the locking ring 39 made of plastic can be produced in an injection molding process in particularly large numbers and thus particularly cost-effectively.

Claims

claims

1. Injection device for injecting a liquid, in particular a medicament, into a subcutaneous tissue, with an ampoule body, with a chamber arranged in the ampoule body and having an opening, with an ampoule piston for reducing the volume of the chamber, with a movable one against a spring element e holding element pretensioned pressure piece and with a trigger for moving the holding element from a first position holding the pressure piece into a second position releasing the movement of the pressure piece and with a basic body for holding the trigger and for guiding the pressure piece in the position in the second position Holding element against the end of the ampoule plunger facing away from the chamber, characterized in that the strength of the spring element (5, 34) and the holding element (6, 38) and / or the base body (1, 32) is dimensioned for use for a single injection and means to prevent further injections after are intended for the first use.

2. Injection device according to claim 1, characterized in that the ampoule body (2, 33) is inseparably connected to the base body (1, 32) after assembly.

3. In _j ection device according to claim 1 or 2, characterized in that the spring element (5, 34) after assembly is inaccessible between the ampoule body (2, 33) and the base body (1, 32).

4. In _j ection device according to at least one of the preceding claims, characterized in that the basic body (1, 32) is made of plastic.

5 Injection device according to at least one of the preceding claims, characterized in that the base body (1, 32) made of plastic is manufactured by injection molding.

6. Injection device according to at least one of the preceding claims, characterized in that a bearing of the trigger (37) has a bearing shell (36) which is open on one side.

7. Injection device according to at least one of the preceding claims, characterized in that the trigger (21) in a guide (27, 28) of the base body (1) is held axially displaceable transversely to the direction of movement of the pressure piece (4).

8. Injection device according to at least one of the preceding claims, characterized in that the trigger (21) has a pressure plate (22) which can be displaced perpendicularly to the direction of movement of the pressure piece (4) and a base (1) encompassing the guide (27, 28 ) arranged arm (23, 29).

9. Injection device according to at least one of the preceding claims, characterized in that the holding element (6) is attached to the end of the arm (23, 29) of the trigger (21) facing away from the pressure plate (22) and a wall of the base body (1) penetrates in the region of an opening (30).

10. In _j ection device according to at least one of the preceding claims, characterized in that the basic body (1, 32) has a latching connection (12, latching hook 41) for holding the ampoule body (2, 33).

11. Injection device according to at least one of the preceding claims, characterized in that the base body (1, 32) at its end facing the ampoule body (2, 33) has latching hooks (13, 14, 41) for engaging behind the spring element (5, 34) facing away from the collar (16, 44) of the ampoule body (2, 33).

12. Injection device according to at least one of the preceding claims, characterized in that a locking ring (39) engages around the locking hooks (41) in the assembled state of the ampoule body (34) on the outside.

13. Injection device according to at least one of the preceding claims, characterized in that the locking ring (39) radially at least one inwardly facing hook (45, 48) for its positive connection with the ampoule body (33) or the base body (32) in the the locking hook (41) has the position.

14. Injection device according to at least one of the preceding claims, characterized in that the latching hooks (13, 14, 41) on the end of the base body (1, 32) facing away from the spring element (5, 34) form a funnel (19) forming embryos (17 , 18, 42).

15. In _j ektionseinrichtung according to at least one of the preceding claims, characterized in that the base body (1, 32) comprises for limiting the axial mobility of the Ampullenkorpers (2, 33) in the space provided on the printing stucco (4, 35) indicative of the direction to ^¬ impact (15, 43).

16. In ektionseinrichtung _j according to at least one of the preceding claims, characterized in that the C

Basic body (1) has a guide (20) for a central area of the ampoule bulb (11 ¹ .

17. In ection device according to at least one of the preceding claims, characterized by a spring element (5) at the end opposite the pressure piece (4) which supports the cap (8) and fastens to the base body (1).

18. Inj ektionsemπchtung according to at least one of the preceding claims, characterized in that the connection of the cap (8) with the basic body (1) has a latching connection (7).

19. Injection device according to at least one of the preceding claims, characterized in that the base body (32) for receiving the spring element (34) and the pressure piece (35) is pot-shaped.

20. In ection device according to at least one of the preceding claims, characterized in that the securing element (24, 40) holding the trigger (21, 37) is held with an intended force m in the position blocking the movement of the trigger (21, 37).

21. Injection device according to at least one of the preceding claims, characterized in that the locking ring (39) on the base body (32) slidably guided and the locking element (40) is arranged on the locking ring (39).

22. Injection device according to at least one of the preceding claims, characterized in that the pressure piece (4, 35) is made of steel in the extrusion process.