WO1992022338A1

WO1992022338A1 - Process for operating a device for administering a liquid medical therapeutic substance to a body to be treated and device for carrying out the process

Info

Publication number: WO1992022338A1
Application number: PCT/EP1992/001383
Authority: WO
Inventors: Mohandes Bader
Original assignee: Bader & Partner Medizintechnik Gmbh
Priority date: 1991-06-19
Filing date: 1992-06-19
Publication date: 1992-12-23
Also published as: DE4120267A1

Abstract

A process is disclosed for operating a device (1) for administering a medical therapeutic liquid to a body to be treated by means of a cylinder-piston unit provided with a hollow needle. A vacuum chamber (16) is arranged in the cylinder-piston unit behind the rear point of the needle, the anterior front wall (19) of the vacuum chamber (16) is pierced by the needle when the movable part (4) of the cylinder-piston unit is moved forwards, the therapeutic liquid is sucked in, then pressed out of the vacuum chamber (16) when the movable part (4) of the cylinder-piston unit is further moved forward.

Description

Method for operating a device for delivering a liquid medical treatment substance to a body to be treated and device for carrying out the method

description

The invention relates to a method and a device according to the preamble of claim 1.

For the injection of a liquid medical treatment substance into a body to be treated, it is customary to use a so-called syringe in the form of a cylinder-piston unit. Such a cylinder-piston unit consists of a hollow cylinder closed at the front by an end wall and a piston which can be pushed into the hollow cylinder from the rear and which delimit a cylinder space which is open to the front end of the cylinder through a hollow needle passing through the end wall. Before an injection, the treatment agent must first be sucked into the cylinder chamber. For this purpose, the plunger is pushed in, if necessary, and the needle tip is immersed in the desired treatment substance. The piston is then withdrawn, as a result of which the treatment material is sucked in due to the vacuum that is created in the cylinder space. After that, after a usual ventilation of the cylinder space, the injection is carried out by inserting the needle tip into the body and advancing the piston in the cylinder. The injection can be carried out by one-hand operation, the cylinder being held with two fingers of the hand and the piston being pushed in with the thumb. Such one-handed operation is not possible when the treatment material is sucked in. In this case the operator must use both hands and hold the cylinder with one hand and pull the piston backwards with the other hand.

A syringe described above can be used not only to inject a treatment substance, but also to withdraw a liquid, in particular from the body to be treated, e.g. for taking blood. For this purpose, the needle is inserted into the blood vessel when the piston is pushed in, and then the blood sample is sucked into the cylinder space by pulling back the piston with two-hand operation.

Both hands of the treatment person are used by the two-hand operation. This is undesirable.

In order to avoid two-hand operation, it has become common to use so-called spray ampoules, in which an ampoule with the treatment substance is integrated into the syringe and therefore there is no need to suck the treatment substance into the cylinder space. Such a spray ampoule is e.g. described in DE-OS 38 23 266. In this known embodiment, the spray ampoule forms the cylinder of the cylinder-piston unit.

In order to make handling easier when taking blood, devices have been developed in which, instead of the piston, an evacuated suction container is inserted into the hollow cylinder from behind. To draw blood, the suction container is advanced so far that its front end wall is pierced by the rear end of the needle. As a result, the vacuum can propagate into the needle, whereby the blood is automatically sucked into the vacuum container. Such a blood sampling device is described, for example, in US Pat. No. 4,758,231 and in WO 89/04678 described. These known blood sampling devices are not suitable for use as syringes because there is no possibility of pushing the liquid in the vacuum container out of the vacuum container. Consequently, the method for taking blood described in these publications is also unsuitable for delivering a liquid to the body to be treated.

The invention has for its object to develop a method and an apparatus of the types mentioned above so that one-handed operation is guaranteed.

This object is solved by the features of claim 1. Advantageous developments of the invention are described in the subclaims.

In the solutions according to the invention, the cylinder-piston unit is only to be acted upon in the forward-facing positive direction both for sucking in the treatment substance into the cylinder space and for delivering it to the body to be treated. This can be done in a simple and easy-to-use manner by one-hand operation. This is of great importance for a contamination-free treatment of a human or animal body. It should also be borne in mind that a device of the present type is a mass product, so that the requirement for the lowest possible manufacturing effort and material consumption is specified. These requirements are also met in an advantageous manner by the device according to the invention.

The further claims contain features which contribute to the problem solutions described above, lead to simple, small-scale and inexpensive configurations and furthermore improve the sealing and protection of the device both before and after its use. In addition, it is ensured that reuse of the device is impossible after use. A device designed according to these features represents a so-called single-use syringe. The invention is explained in more detail below on the basis of preferred exemplary embodiments and a simplified drawing. Show it

1 shows a device according to the invention in axial longitudinal section;

Figures 2 and 3, the device in different functional positions;

4 shows a device according to the invention in a modified configuration in axial longitudinal section;

5 to 8 the device according to FIG. 4 in different functional positions;

9 shows a device according to the invention in a further modified embodiment in an axial longitudinal section.

The main parts of the so-called medical syringe device 1 are a hollow cylinder 2, which is closed at its front end by an end wall 3 and is open at its rear end, a piston 4 which can be inserted into the hollow cylinder 2 from the rear and is guided with its outer circumferential surface 5 on the inner circumferential surface 6 of the hollow cylinder 2 and which defines a cylinder space 7 with the hollow cylinder 2, and a hollow needle 8 which axially penetrates the end wall 3 of the hollow cylinder 2 and thereby in an axial through hole 9 of a needle holder 11 is firmly inserted, which is integrally formed on the inside on the end wall 3 and is formed by a tubular connecting piece 12 and which extends axially into the vicinity of the rear end of the hollow cylinder 2 centrally in the cylinder space 7. On the outside of the end wall 3, a short tubular outer connector 13 is integrally formed in an extension of the inner connector 12, which the needle 8 projects forward by the required insertion length. The needle 8 is pointed on both the front and the back, with its rear end projecting beyond the rear end of the inner connector 12 by a few millimeters. A hollow cylindrical protective cap 14 for the outwardly projecting section of the needle 8 is placed on the outer connecting piece 13 and is closed at its front end. The free edge 15 on the back clampingly overlaps the outer connector 13.

The hollow cylinder 2, the piston 4, the protective cap 14, the needle 8 and the connecting piece 12, 13 are preferably of circular cross section.

The piston 4 is formed by a vacuum container 16, which is closed on the rear by a bottom wall 17 and is sealed and sealed on the front by a sealing insert 19 sealingly sealing into its hollow cylindrical peripheral wall 18.

The sealing insert 19 is of pot-shaped design with a hollow cylindrical peripheral wall 21 and a bottom wall 22, the peripheral wall 21 projecting forward from the bottom wall 22 and approximately terminating in the inserted position with the front edge of the peripheral wall 18 of the vacuum container 16. To improve the seal, a clamping ring 23 is arranged coaxially in the region of the front end of the vacuum container 16, the outside diameter of which is dimensioned a few millimeters smaller than the inside diameter of the vacuum container 16, the clamping ring 23 being arranged in the peripheral wall 18 and the latter is clamped radially between the clamping ring 23 and the peripheral wall 21 of the vacuum container 16. To further improve the seal, one or more locking beads or ring lips can be provided on the inner and outer surface of the peripheral wall 21, on the inner wall of the peripheral wall 18 and / or on the outer wall of the clamping ring 23. At its front edge, the clamping ring 23 has an outwardly projecting flange 25 which bears on the front end face of the vacuum holder 16. The sealing insert 19 consists of a soft elastic material such as plastic or rubber. The mode of operation of the device and the method for dispensing a liquid treatment substance to a human or animal body in particular are described below. The device 1 is in the initial position shown in FIG. 1, in which the piston 4 or the vacuum container 16 is in its rear end position, in which its front end surrounds the hollow cylinder 2 for a short distance. This position can be marked by a pressure point. This is achieved by one or two annular beads 26 on the inner lateral surface 6 of the hollow cylinder 2 in its rear end area and one or two annular beads 27 on the outer lateral surface 5 of the vacuum container 16 in its front end area, the annular bead 27 of the vacuum container in the above-described initial position 16 is located between the annular beads 26 of the hollow cylinder 2. As a result, the pressure point or a certain overpressable latching is given. In this function-ready starting position, the protective cap 14 is removed and the front needle tip is immersed in the liquid to be injected into the body, which can be kept ready, for example, in an ampoule. The patient holds the device 1 between her thumb pressing on the back of the vacuum container 16 and two further fingers, which grip two support arms 29 projecting outwards from the back end of the hollow cylinder 2 and an opposing back pressure exercise. The vacuum container 16 is inserted until the rear needle tip pierces the bottom wall 22 of the sealing insert 19 and the liquid is sucked into the vacuum container 16 automatically due to the negative pressure. Thereafter, by further pushing in the vacuum container 16, it can be vented in the usual way, the sealing insert 19 abutting against an abutment 31 formed by the rear end of the needle holder 11 and the sealing insert 19 pushed into the hollow cylinder 2 or the vacuum container 16 opened the sealing insert 19 is pushed on (Fig. 2). The injection is then carried out by setting the needle 8 and further inserting the vacuum holder 16, the vacuum container 16 being pushed further over the sealing insert 19 and the liquid being pressed out by the needle 8.

In order to prevent further use after the device 1 has been used, the hollow cylinder 2 and the vacuum container 16 are dimensioned so long that their rearward ends approximately terminate in the inserted position (FIG. 3). It is then no longer possible to pull out the vacuum container 16.

A means can also be provided which, although it allows the vacuum container 16 to be pushed in, does not allow the vacuum container 16 to be withdrawn. This can be achieved by interlocking teeth 32, 33 (Fig. 1) on the inner circumferential surface 6 of the hollow cylinder 2 and the outer circumferential surface 5 of the vacuum container 16, at least one of which can be sawtooth-shaped so that withdrawal of the vacuum container 16 is blocked.

The above-described measures are achieved in the case of handling-friendly one-hand operation only by inserting the vacuum container 16 toward the front. Retraction of the vacuum container 16, as is the case with known syringes, in order to draw in the treatment liquid, is not necessary and is also not possible if a suitable retraction lock is present.

The device 1 is also suitable for removing an optional liquid, e.g. a body fluid like blood. For this purpose, the vacuum container 16 after inserting or immersing the needle 8 only has to be pushed in until the needle 8 pierces the sealing insert 19, in which case the liquid and the vacuum container 16 are automatically removed by suction. The vacuum container 16 can then be pulled out of the hollow cylinder 2 to the rear and serve as a transport container for the liquid removed.

4 to 8, in which the same or comparable parts are provided with the same reference numerals, the needle 8 is from a starting position in which is retracted into the hollow cylinder 2, can be retracted back into the hollow cylinder 2 after use in the extended position. This is achieved by means of a telescopic arrangement of the needle holder 11 or inner socket 12 and a coupling possibility between the vacuum container 16 and the rear end region of the needle holder 11, through which the rear telescopic part of the needle holder 11 by means of one at the rear end of the vacuum container ters 16 preferably one-piece molded handle 33 can be retracted so far that the needle 8 is substantially in the hollow cylinder 2. The pull handle 33 consists of three longitudinally extending, star-shaped, radially arranged webs 33a connected to one another at their mutually associated longitudinal edges and a front plate 33b projecting over them at the rear end thereof.

In detail, the needle holder 11 consists of a front and a rear telescopic part 11a, 11b. The rear telescopic part 11b has a pot-shaped, open-ended shape with a peripheral wall 34 and a bottom wall 35 forming the abutment 31, which is penetrated by the needle 8 in a hole and sits firmly and immovably on the needle 8. The rear telescopic part 11b is dimensioned so large on the inside that it can be moved axially with play on the front telescopic part 11a, and dimensioned on the outside so that its rear end preferably plunges into the flange 25 and the clamping ring 23 with difficulty can At the front edge of the rear telescopic part 11b, latching hooks 36 are arranged which are elastically bendable radially inwards and whose latching lugs protrude radially outwards. The locking hooks 36 can be immersed in a manner to be described through a hole 37 in a locking disk 38 and lock behind the edge of the hole. The locking disk 38 is in the starting position according to FIG. 4 at a short distance from the end wall 3 of the hollow cylinder 2. The clamping ring 23 and the needle holder 11 are designed in their mutually facing end regions so that the clamping ring 23 is difficult to move, e.g. B. in the sense of a pressure point in the edge area, can be pushed onto the rear telescopic part 11b. This will at the initial Pushing the piston 4 exerts a pushing force on the rear telescopic part 11b, which shifts it into the position according to FIG. 5, in which the latching hooks 36 latch in the hole 37. The bottom wall 22 should not yet abut the rear needle tip.

The above-mentioned coupling between the vacuum container 16 and the rear telescopic part 11b is preferably formed by a latching device, which has one or two axially spaced, optionally annular locking elements 39 arranged on the outer circumferential surface of the telescopic part 11b, preferably in the form of a forward-facing sawtooth, which interacts with the preferably sawtooth-shaped inner rear edge 41 of the clamping ring 23.

In this embodiment, the flange 25 of the clamping ring 23 is fastened to the peripheral wall 18 in order to be able to transmit a retraction force. An annular wall 25a projecting from the flange 25 is preferably used for this purpose, with an inner shoulder which is latched into an outer groove in the peripheral wall 18, as a result of which a latch 25b is formed.

In this embodiment, since the needle 8 can be retracted into the hollow cylinder 2, the protective cap 42 can be made short. It is preferably a double protective cap with a common central protective cap base 43. While one end of the protective cap 42 is hollow-cylindrical, sawtooth-shaped latching elements 42a are preferably provided at the other end, namely at the front end in FIG a locking ring groove 44 can be snapped into the circumferential surface of the outer connector 13 so that it cannot be detached (FIG. 8).

In this embodiment, a hollow cylindrical protective cap 45 is also provided for covering the rear of the hollow cylinder 2. The protective cap 45 covers the vacuum container 16 and the pull handle 33, and its free edge is clamped between the vacuum container 16 and the hollow cylinder 2. To use this device 1, the protective caps 42 and 45 are removed, and then, in accordance with the first exemplary embodiment, the needle 8 is first partially pushed out of the hollow cylinder 2 toward the front into its operating position according to FIG. 5 by one-hand operation. For this purpose, a forward pressure is exerted on the pull handle 33, the vacuum container 16 advancing the rear telescopic part 11b into its foremost position, in which the latching hooks 36 lock behind the locking disk 38. Then the needle tip is immersed in the treatment liquid and the vacuum container 16 is advanced into the position shown in FIG. 6, in which the rear needle tip pierces the bottom wall 22 of the sealing insert 19 and the clamping ring 23 so far onto the rear telescopic part 11b is pushed on that the latter abuts the bottom wall 17 and that the abutment 31 forms here in this position. From this position, the vacuum container 16 can be vented as usual by a further slight insertion. After the needle 8 has been set, the liquid which is automatically sucked in after the piercing into the vacuum container 16 can be injected, the vacuum container 16 being pushed in further, the sealing insert 19 being released from its holder, clamping or latching and the vacuum container 16 is moved over the sealing insert 19 to the front end position shown in FIG. 7, the treatment liquid being expressed through the needle 8. In the fully inserted end position, the one or more locking elements 39 lock behind the rear edge 41 of the clamping ring 23. After the injection, the vacuum container 16 is pulled back into the position according to FIG. 8 by pulling on the pull handle 33 which protrudes on the rear side, in which the needle 8 moves be¬ in the hollow cylinder 2. In this case, the locking disk 38 is also retracted into its locking position according to FIG. 8 by the latching hooks 36, in which, due to its forward concave curvature, it is jammed on the inner wall of the cylinder 2 when the piston 4 is pushed forward again and thus pushed forward or out again locks. It is therefore a high security against reuse of the Device 1 and protection of medical personnel against injury by an infected needle 8 is created.

To clarify the above-described functional positions of the vacuum container 16, further ring beads 26a, 27a comparable to the ring beads 26, 27 can be provided on the inner circumferential surface 6 of the hollow cylinder 2 and the outer circumferential surface 5 of the vacuum container 16, each of which can be pushed over by pressure or locking points 6 and in the retracted position according to FIG. 8. In order to improve the displaceability of the needle 8 in the stationary telescopic part 11a, it is advantageous to provide at least two inner beads 11c in the end regions thereof, which guide the needle 8. A liquid-tight seal between the hollow cylinder 2 and the vacuum container 16 is not required.

In the embodiment according to FIG. 9, in which a vacuum container is preferably also used, the device 51 is of a different construction. Here, a hollow cylinder 52 is provided, the end wall 53 of which is located at the rear end and which, with its front end open, can be pushed onto the rear end of a rod-shaped needle holder 55 forming a stationary piston 54. The hollow needle 56 sits in the existing central axial through-hole 57 of the needle holder 55 and protrudes with its front end by a larger amount and with its rear end by a smaller amount from the needle holder 55.

If a vacuum container 58 is realized, the sealing insert 59, which is plug-shaped here, is at a distance a from the front end of the hollow cylinder 52, this end, in the illustrated starting position, engaging over the rear end of the needle holder 55 by the dimension b without tilting. For manually felt definition of this starting position between the hollow cylinder 52 and the needle holder 55, a push-fit latching is provided, which is formed by a locking ring 62 formed on the outer surface 61 of the needle holder 55 and at least one locking ring partially receiving groove is formed in the inner circumferential surface of the hollow cylinder 52. In this starting position, the rear needle tip dips into a central recess 63 which is open at the front in the sealing insert 59, so that a tapered wall 64 faces it on the rear. For axial locking, a catch 65 is provided for the seal insert 59, which is formed by a catch ring on the outer surface of the seal insert 59 and a catch groove receiving it in the inner wall of the hollow cylinder 52.

In the approximately central region of the hollow cylinder 52, a flange 66 is formed thereon. A comparable flange 67 is formed in the front area of the needle holder 55 on its outer surface. The flanges 66, 67 serve to hold a packaging in the form of a protective cap 68, which can be attached from the front and with a tapered cap section 69 the protruding needle 56 and with a step-widened cap section 71 the needle holder 55 each at a radial distance engages, with the rear end of the protective cap 68 projecting slightly beyond the flange 66 to the rear. To lock the protective cap 68 in its mounted position, locking projections 72 can be formed on its inner wall, which engage one of the two flanges 66, 67, preferably the rear flange 66, in the fitted position of the protective cap 68. The protective cap 68 has a divergent conical shape toward the rear in order to make it easy to attach. The flanges 66, 67 are sized differently in terms of their diameter. In its plugged-on position, the flange 66 lies with its circumferential surface close to the inner surface of the protective cap 68, as a result of which excellent protection for the device 51 against soiling is achieved in a simple manner. The one or more locking projections 72 can also form stops for the one or more flanges 66, 67, at which the plug-on position of the protective cap 68 can be limited with radial clamping action against the one of the flanges 66, 67. Functionally, the device 51 corresponds to the previously described exemplary embodiments. Here too, the treatment liquid is automatically sucked in after piercing the sealing wall 64 and the treatment liquid is injected by moving the hollow cylinder 52 or vacuum container 58 in only one direction, namely by moving it forward. During this displacement, the latching 65 of the sealing insert 59 is overpressed, so that here too the sealing insert 59 on the inner wall of the vacuum holder 58 is able to slide, after the sealing insert 59 has struck against the needle holder 55 forming an abutment 73 of the vacuum container ter 58 is pushed over the sealing insert 59.

For the non-releasable locking of the vacuum container 58 in its fully pushed forward position, a sawtooth-shaped locking ring 74 is provided on the lateral surface of the needle holder 55 in its front area, which locks into the existing locking groove on the inner wall of the vacuum container 58 and a withdrawal of the vacuum container and thus further use of the device 1 prevented.

With the exception of the sealing insert 19 or 59, which preferably consists of soft elastic rubber, and the needle 8 or 56, all other parts are preferably made of plastic and are produced by injection molding.

Claims

Method for operating a device (1; 51) for delivering, in particular for injection, a medical treatment liquid to a body to be treated using a cylinder-piston unit with a hollow needle (8; 56), in which the liquid sucked the cylinder space and then when the movable part (4; 52) of the cylinder-piston unit is advanced through the needle, characterized by the use of a vacuum container (16.) arranged in the cylinder-piston unit behind the needle (8; 56) ; 58), which is moved forward with the movable part (4; 52) after immersing the needle in the liquid to be sucked in, the front wall (22; 64) of the vacuum container being pierced with the rear end of the needle and the Liquid is sucked into the vacuum container, and then the liquid by moving the movable part (4; 52) and by compressing or pushing the vacuum container together s (16; 58) from the vacuum container (16; 58) is expressed by the needle (8; 56).

2. The method according to claim 1, characterized in that in the formation of the movable part (4; 52) of the cylinder piston unit as a vacuum container (16; 58) the latter both for piercing and for moving forward and the front end wall (19) in the Vacuum container (16; 58) is inserted.

3. The method according to claim 1 or 2, characterized in that a cylinder-piston unit with a recessed therein needle (8; 56) is used and that when moving the movable part (4; 52), the needle (8th ; 56) is pushed out before being immersed by pushing the movable part (4 59) in the same direction of movement.

4. The method according to one of the above *: ^* several of the preceding claims, characterized in that the movable part (4; 52) in its advanced position with a part (11b) supporting the needle (8; 56) and locked after injection or administration of the aspirated liquid can be withdrawn into the cylinder-piston unit.

5. The device, in particular for performing the method according to one or more of claims 1 to 4, consisting of a cylinder-piston unit, the cylinder space by an axial displacement of the movable part (4; 52) of the cylinder-piston unit its size can be varied, and a hollow needle (8; 56) which extends through the front end of the cylinder-piston unit and extends from the outside inwards and is held in a needle holder (11; 55) which it projects with its rear end, characterized in that a vacuum container (16; 58) is provided in the cylinder space behind the needle (8; 56), which is closed at its preferably front end by a sealing insert (19; 59) and by advancing the movable part (4; 52) of the Cylinder-piston unit can be advanced so far that the rear needle tip pierces the front end wall (22; 64) of the vacuum container (16; 58), and by further advancing the movable part (4; 52) of the cylinder-piston unit Vacuum container (16; 58) can be compressed or pushed together.

6. The device according to claim 5, characterized in that one of the end walls (19; 59) of the vacuum container (16; 58), preferably its front end wall (19), can be inserted into it, the latter being arranged upstream of an abutment (31) that the vacuum container (16; 58) can be pushed on.

7. Apparatus according to claim 5 or 6, characterized in that the rear needle tip projects beyond the needle holder (11; 55) by an amount which is greater than the thickness of the sealing insert (19; 59) that the needle holder in its rear end region in its cross-sectional shape and size is equal to or smaller than the inner cross-sectional shape and size of the vacuum container (16; 58) and that the movable part (4; 52) with a relative displacement between the vacuum container (16; 58) and the sealing insert (19 ; 59) on the rear end region of the needle holder (11; 55) can be pushed.

8. The device according to one or more of the preceding claims, characterized in that the cylinder-piston unit einfas¬ a front side by an end wall (3) closed and back open Hohlzylin¬ der (2) and one from behind in the hollow cylinder (2) Send piston (4) and that the needle holder (11) is formed by a tubular connector (12) extending from the end wall (3) to the rear.

9. The device according to claim 8, characterized in that the piston (4) is the movable part and is formed by the vacuum container (16).

10. The device according to one or more of the preceding claims, that the rear end of the piston (4) is inserted into the rear end thereof

Position with the rear end of the hollow cylinder (2) approximately completes.

11. The device according to one or more of the preceding claims, d a d u r c h g e k e n n z e i c h n e t that the movable part (4; 52) is assigned a retraction lock.

12. The apparatus according to claim 11, characterized in that on the inner circumferential surface (6) of the hollow cylinder (2) and de outer circumferential surface (5) of the piston (4) a toothing (32, 33) with one behind the other in the longitudinal direction of the cylinder-piston unit the lying teeth is provided, which allows the piston (4) to be pushed forward, but prevents the piston (4) from being retracted.

13. The device according to one or more of the preceding claims, characterized in that the needle holder (11) is longitudinally displaceable or telescopic and in its rear region (11b) by a coupling device (39, 41) with the piston (4) in it pushed forward position for a common withdrawal movement can be connected, in particular locked.

14. The apparatus according to claim 13, so that the rear telescopic part (11b) can be pushed onto the front telescopic part (11a).

15. The apparatus according to claim 14, characterized in that Rastha¬ ken (36) are arranged at the front end of the rear tele “Kopteile (11b), one in the front area of Hollow cylinder (2) arranged, with its periphery in contact with the inner surface (6) of the hollow cylinder (2) in contact with the locking disk (38) can preferably be locked in a hole (37) thereof.

16. Device according to one or more of the preceding claims, characterized in that the displaceable end wall is a sealing insert (19) which is cup-shaped with a bottom wall (19) and a peripheral wall (21) projecting forwardly therefrom, and in that the peripheral wall ( 21) is radially clamped between the inner wall of the vacuum container (16) and a preferably sleeve-shaped clamping ring (23) which has a flange (25) at its front end which is larger than the inner Guer section dimension of the vacuum container (16).

17. The apparatus of claim 16, d a d u r c h g e k e n n z e i c h n e t that the clamping ring (23) on its outer lateral surface has locking and / or sealing beads or lips.

18. The apparatus of claim 16 or 17, d a d u r c h g e k e n n z e i c h n e t that on the inner and / or outer peripheral surface of the peripheral wall (21) of the sealing insert (19) locking and / or sealing beads or lips are provided.

19. The device according to one or more of the preceding claims, characterized in that the flange (25) with the front edge of the vacuum container (16) facing it can be fastened, in particular latched, preferably by a rearwardly extending peripheral wall (25a ), which can be snapped into a circumferential groove of the vacuum container (16).

20. The device according to one or more of the preceding claims, characterized in that between the inner peripheral surface (6) of the hollow cylinder (2) and the outer peripheral surface (5) of the piston (4) formed by annular beads (26, 27) locking elements are effective, which in the starting position, in the suction position, in the end position and / or in the retracted position of the piston (4) correspond with each other and specify pushable snap points.

21. The device according to one or more of the preceding claims, d a d u r c h g e k e n n z e i c h n e t that the movable part of the cylinder-piston unit

Cylinder (58) is from behind on one

Needle holder (55) forming stationary piston (54) can be pushed.

22. The apparatus according to claim 21, so that it has a protective cap (68) which can be pushed tightly from the front onto the preferably circular cylinder (58).

23 Device according to claim 22, so that the cylinder (58) and preferably also the needle holder (55) each have a flange (66, 67) on which the protective cap (68) is seated.

24. The device, in particular according to one or more of the preceding claims, characterized in that it has at the front end a preferably cylindrical socket (13) surrounding the needle (56), onto which the protective cap (42) can be attached, and the protective cap ( 42) has a central base (43) and can be plugged on with one or the other end, with at least one latching element (42a) on one end region of the protective cap (42) which cannot be detached from a latching recess (44) on the nozzle (1) can be snapped into place.

25. The device according to one or more of the preceding claims, that a handle (33) is arranged on the back of the vacuum container (16), preferably integrally formed, on the back.

26. The device according to one or more of the preceding claims, d a d u r c h g e k e n n e e c h n e t that a hollow cylindrical protective cap (45) is assigned to the rear, which can be used between the vacuum container (16) and the hollow cylinder (2).