CN209848026U - Injection head of needleless injector, injection head assembly and needleless injector - Google Patents

Abstract

The utility model relates to an injection head, injection head subassembly and needleless injector of needleless injector. According to the utility model discloses a needleless injector's injection head is formed with the injection microcavity including being used for fixing to needleless injector's base in the base, and the injection microcavity accesss to the injection micropore that is used for outside injection liquid medicine that forms at the front side of base at the front end of base one side, and the base rear side is equipped with the pjncture needle that protrudes to the rear side, and wherein, the pjncture needle has the cavity main part, and the cavity of cavity main part forms and injects the main route of microcavity intercommunication, is equipped with at least one opening at the lateral wall of the cavity main part of pjncture needle. Through the utility model discloses, can be with the components of a whole that can function performance structure split for the achievable components of a whole that can function independently part of processing technology, it can form wholly through the equipment mode, has both guaranteed the functionality from this and has ensured that processing technology easily realizes when the productization again, has realized controllable manufacturing cost.

Description

Injection head of needleless injector, injection head assembly and needleless injector

Technical Field

The utility model relates to a medical instrument for injecting liquid medicine. More particularly, the present invention relates to an injector head for a needleless injector, in particular a prefilled needleless injector, and a needleless injector, in particular a prefilled needleless injector, having such an injector head.

Background

The needleless injector does not need to use a needle, but is a medical device which can inject liquid medicine into the subcutaneous part of a patient through micropores at the end part by applying high pressure to the liquid medicine, thereby being capable of preventing the patient from suffering from acupuncture. Needleless injectors generally comprise a cartridge and a pusher. The medicine tube has the function of containing liquid medicine, the medicine tube shell and the piston inside the medicine tube seal the medicine liquid, and when the pusher pushes the piston to move, the medicine liquid is pressurized, ejected out at high speed through the micropores prefabricated at the front end of the medicine tube and injected into a human body. The cartridge is generally sterilized and used once. The pusher is a device for providing power for the movement of the piston in the cartridge. The pusher generally does not require sterilization and can be used once or repeatedly.

Currently, the drug tube is filled with drug solution in two ways, and the drug tube is pre-filled in a pharmaceutical factory (drug solution pre-filling) or the drug solution is introduced into the drug tube by using a tool such as a drug taking port during injection. The pre-filling of the liquid medicine saves the work of leading the liquid medicine into a medicine tube in the using process of a patient, and can improve the convenience of needle-free injection and the safety of medicines, so that some needle-free injector companies and pharmaceutical factories cooperate to develop and produce pre-filled needle-free injectors at present.

The key technology of the pre-filled needleless injector is to fill the liquid medicine into the medicine tube of the needleless injector. There are currently two commonly used solutions: in the first scheme, a medicine tube is used as a medicine container and is placed between a micropore of a needleless injector and a piston, a rubber cap is used for sealing the micropore end of the needleless injector, the rubber cap at the micropore end is removed during injection, and the piston is driven by a pusher to extrude medicine liquid for injection (a typical product is Pharmajet)Pre-filled)；In the second embodiment, the drug solution is stored in a separate drug vial, and is injected into the drug tube of the needleless injector from the drug vial through a pre-prepared passage before injection, and then the needleless injector is injected after the connection with the drug vial is removed.

The use of a prefilled needleless injection protocol has the following difficulties:

one difficulty is that: it is necessary to verify the safety of the drug storage in the cartridge and the compliance of the drug package usage. Most of the medicines are stored in a cartridge as a glass bottle and sealed with a rubber stopper of a specific material. Although polymer materials are also widely used in the field of drug packaging materials, the application examples which can be used as a basis for approval are not very common. It is difficult to form precise micro-holes in the glass cartridge and ensure that no debris is generated under high pressure injection conditions.

Difficulty two: the equipment reconstruction cost of the pharmaceutical factory is high. The canning production line of a pharmaceutical factory is designed and customized for products with standard specifications, and if the form and the specification of a pre-filled medicine tube in the liquid medicine pre-filling process are greatly different from those of the standard products, the initial equipment cost of the production is higher.

Accordingly, there is a need for a corresponding solution that can be used quickly, conveniently and safely with needleless injectors.

SUMMERY OF THE UTILITY MODEL

In order to overcome the above drawbacks, according to the present invention, an injector head for a needleless injector, in particular a prefilled needleless injector, and a needleless injector, in particular a prefilled needleless injector, having such an injector head are proposed.

According to the utility model discloses an injection head for needleless injector, including being used for fixing to the base of needleless injector, be formed with the injection microcavity in the base, the front end of injecting the microcavity accesss to the injection micropore that is used for outside injection liquid medicine that forms at the front side of base, and the base rear side is equipped with the pjncture needle that protrudes to the rear side, and wherein, the pjncture needle has the cavity main part, and the cavity of cavity main part forms and injects the main route of microcavity intercommunication, is equipped with at least one opening at the lateral wall of the cavity main part of pjncture needle.

According to a preferred embodiment of the invention, the hollow body is constructed integrally with the base.

According to a preferred embodiment of the invention, the hollow body is detachably connected to the base.

According to a preferred embodiment of the invention, the hollow body is connected to the base in a form-fitting manner.

According to the utility model discloses a preferred embodiment, the cavity main part is equipped with outstanding card foot and the base is equipped with corresponding draw-in groove, and the cavity main part passes through card foot and draw-in groove fixed connection each other with the base.

According to a preferred embodiment of the present invention, a sealing ring is provided between the hollow body and the base.

According to a preferred embodiment of the invention, the hollow body is detachably connected to the piercing needle tip.

According to a preferred embodiment of the invention, the hollow body and the piercing needle tip are connected to one another at the opening, in particular in a form-fitting manner.

According to a preferred embodiment of the invention, the puncture needle tip has no opening in the puncture direction.

According to a preferred embodiment of the invention, the injection microcavity has a cross-section, in particular a tapered cross-section, which tapers towards the injection micro-hole.

According to a preferred embodiment of the invention, the main passage has a uniform diameter or a non-uniform diameter.

According to a preferred embodiment of the invention, the mean diameter of the main passage is much greater than the mean diameter of the injection microcavity.

According to a preferred embodiment of the invention, the at least one opening is located close to the piercing needle tip.

According to another aspect of the present invention, an injection head assembly is provided, which comprises the injection head as described above and a fixing sleeve capable of detachably fixing the injection head.

According to a preferred embodiment of the invention, the fixing sleeve has a radially inwardly extending flange at the front end and thus forms the opening.

According to a preferred embodiment of the invention, the injection head has a contour matching the flange.

According to a further aspect of the invention, a needleless injector is proposed, in particular a prefilled needleless injector, comprising a tubular main body and a syringe assembly as described above detachably fixed at the front end of the main body, the main body comprising a front cartridge receiving chamber for receiving a cartridge and a pusher receiving chamber in which the pusher is arranged, a rear pusher receiving chamber and a transition between the cartridge receiving chamber and the pusher receiving chamber, wherein the cartridge can be placed between the syringe assembly and the pusher in an inner cavity of the main body, wherein the cartridge is a tubular container for receiving a liquid medicament and has a front rubber plug on a side close to the syringe assembly, a rear rubber plug on a side close to the pusher, and the pusher can pass through the transition when being axially moved by the force of the pusher, Against and push the rear plug.

According to a preferred embodiment of the invention, the front rubber plug has a recess on the side facing the injector head, which is adapted to the shape of the puncture needle tip, in order to be penetrated by the puncture needle tip.

According to a preferred embodiment of the present invention, the rear rubber plug has a concave portion matching the shape of the puncture needle tip on one side facing the injection head, so as to evacuate the liquid medicine contained in the medicine storage tube when the push rod pushes the rear rubber plug to be close to the front rubber plug.

According to a preferred embodiment of the invention, the pusher comprises an actuating mechanism and a push rod in contact with the actuating mechanism. In particular, the push rod has an enlarged-diameter end at the end in contact with the actuating mechanism and is embodied as a piston at the end opposite the actuating mechanism.

According to a preferred embodiment of the present invention, the fixing sleeve is fixed to the front end of the main body by a screw connection or a snap connection.

According to a preferred embodiment of the invention, the injection head is reusable.

Since the liquid has a certain viscosity, when the liquid medicine is ejected from the micropore of the injection head in a high-pressure and high-speed state during needleless injection, the larger the cross-sectional area of the passage, the smaller the energy loss (resistance) to the flow process of the passage, and the smaller the energy required for realizing the injection. Therefore, the utility model discloses in, guaranteed through novel structural design that the liquid medicine passageway has enough sectional area except that the micropore, guarantee the functionality of needleless injection. Meanwhile, the possibility of rubber scraps generated when the rubber plug is punctured can be reduced when the tip of the medicine storage tube sealing rubber plug is punctured in the traditional needleless injector, so that the possibility of the rubber scraps entering a medicine liquid passage is reduced. Furthermore, the technical scheme of the utility model considered technology realizability and the processing equipment degree of difficulty, can be the components of a whole that can function performance structure split that the processing technology can realize, it can form wholly through the equipment mode, has both guaranteed the functionality from this and has ensured that the processing technology easily realizes when productization again, has realized controllable manufacturing cost.

Drawings

Fig. 1 shows a cross-sectional view of a portion of the assembly of a needleless injector in accordance with the present invention.

Fig. 2 shows a cross-sectional view of a needleless injector according to the present invention, incorporating an injector head assembly of a preferred embodiment of the present invention.

Figure 3 shows a cross-sectional view of one embodiment of an injection head according to the present invention.

Figure 4 shows a cross-sectional view of another embodiment of an injection head according to the present invention.

Figure 5 shows a cross-sectional view of yet another embodiment of an injection head according to the present invention.

Figure 6 shows a cross-sectional view of a particular construction of a cartridge according to the invention.

Fig. 7 shows a needleless injector according to the present invention in operation.

Detailed Description

Hereinafter, a needle-free injector and an injector head for a needle-free injector according to the present invention will be described in detail with reference to the accompanying drawings. Given the following are only preferred embodiments according to the invention, on the basis of which other ways of implementing the invention can be imagined by those skilled in the art, which also fall within the scope of the invention.

In this specification, one end of the injection head of the needle-less injector, which applies the liquid medicine to the skin of the patient, is a front end, and the other longitudinal end of the needle-less injector is a rear end. Positional terms such as "front", "rear", "left", "right" and the like are set with reference to the front and rear ends of the needleless injector.

The needleless injector 1 of the present invention, particularly a prefilled needleless injector, mainly comprises a main body 10 and an injector head assembly 11 detachably fixed to a front end of the main body 10. As can be seen in particular with reference to fig. 1, the body 10 is generally cylindrical and comprises a drug storage tube receiving cavity 12 at the front, a pusher receiving cavity 13 at the rear and a transition 14 between the drug storage tube receiving cavity 12 and the pusher receiving cavity 13, wherein the drug storage tube receiving cavity 12 is for receiving a drug storage tube 60 (see fig. 2 and 7) and a pusher is provided in the pusher receiving cavity 13. The pusher comprises, for example, an actuating mechanism 30 at the rear and a push rod 40 at the front in contact with the actuating mechanism 30, the push rod 40 having, for example, an end portion with an enlarged diameter at the end in contact with the actuating mechanism 30, i.e., the rear end, thereby being capable of axial movement in the internal cavity of the body 10 under the force of the actuating mechanism 30. The end of the push rod 40 opposite the actuating mechanism 30, i.e., the forward end, may be embodied, for example, as a piston that is movable through the transition 14, against and pushing a rear plug 62 of a drug storage tube 60 received in the drug storage tube receiving chamber 12 (see fig. 7) when the push rod 40 is moved axially by the force of the actuating mechanism 30.

Referring to fig. 2, there is shown a cross-sectional view of a needleless injector 1 in accordance with the present invention having a syringe head assembly 11 and a drug storage tube 60 mounted therein. The injector head assembly 11 comprises an injector head 50 and a fixing sleeve 20 capable of detachably fixing the injector head 50 to the body 10 of the needle-free injector 1. The fixing sleeve 20 has a substantially cylindrical shape, a rear end of which is completely opened so as to be detachably fitted over the front end of the main body 10, and the rear end of the fixing sleeve 20 may be fixed to the front end of the main body 10, for example, on an outer circumferential surface of the front end of the main body 10, for example, by screwing, snapping, or the like. The front end of the fixing sleeve 20 has a radially inwardly extending flange 21 and thus forms an opening 22 (see fig. 1). The injection head 50 may have a profile matching the flange 21 so as to be held securely in place at the front end of the body 10 when secured by the securing sleeve 20 and so that the front end of the injection head 50 can protrude out of the opening 22.

In using the needleless injector 1 according to the present invention, the drug storage tube 60 is first placed in the drug storage tube accommodating chamber 12 of the main body 10, and then the fixing sleeve 20 is fixed to the front end of the main body 10 together with the injector head 5. Thus, the needleless injector 1 of the present invention is in the ready-to-operate state.

Referring to fig. 3, a cross-sectional view of one embodiment of an injector head 50 according to the present invention is shown. The injector head according to the present invention comprises a seat 51 for fixing in the needle-free injector 1, more precisely on the fixing sleeve 20 of the needle-free injector 1, which has a profile corresponding to the configuration of the fixing sleeve 20. An injection micro-cavity 52 is formed in the base 51, a front end of the injection micro-cavity 52 is opened to an injection micro-hole 53 formed at one side of the base 51 for injecting the medical fluid 64 outward, a puncture needle 54 protruding rearward is provided at a rear side of the base 51 opposite to the injection micro-hole 53, the puncture needle includes a hollow body 541 protruding on the base 51, and a puncture needle tip 542 is provided at an end of the hollow body 541 at a side away from the base 51 to penetrate a front rubber plug 61 of the medical fluid reservoir 60 accommodated in the needle-less injector 1 (which will be described in detail below). Wherein the hollow body 541 is a structure (for example, a cylinder) with a hollow inside and the cavity of the hollow body 541 forms a main passage 55 communicating with the injection micro-cavity 52, at least one opening 56 is provided on the sidewall of the hollow body 541 of the puncture needle 54, preferably near the puncture needle tip 542, the opening 56 being capable of introducing the medical fluid 64 contained in the drug storage tube 60 into the main passage 55 after the puncture needle tip 542 penetrates the front rubber plug 61. Although only one opening 56 is shown in fig. 3, it is understood that a plurality of openings 56, for example, 2, 3, 4, 5, 6 openings 56, may be provided in the sidewall of the piercing needle 54 as desired, and the size, configuration, and arrangement of the openings 56 can be set as desired in relation to the desired injection effect. The puncture tip 542 is not open in the puncture direction, i.e., in the axial direction. In particular, in the embodiment according to fig. 3, the piercing needle 54 is preferably constructed in one piece with the base 51. On the other hand, in order to achieve a faster flow rate of the liquid medicine at the time of needle-free injection, the injection micro-chamber 52 has a cross section tapered toward the injection micro-hole 53, for example, a tapered cross section, and the main passage 55 may have a uniform diameter (cylindrical shape) or a non-uniform diameter (tapered cross section), for example, the main passage 55 may also have a cross section tapered toward the injection micro-hole 53, that is, a tapered cross section. The average diameter of the main passage 55 is much larger than that of the injection micro-cavity 52, so as to reduce the flow resistance and realize a faster flow rate when the liquid medicine flows out through the injection micro-holes 53. In particular, the injection micro-holes 53 should be precisely shaped so as to form a concentrated jet.

Referring to fig. 4, a cross-sectional view of another embodiment of an injector head 50 according to the present invention is shown. This differs from fig. 3 in that the puncture needle 54 is not integrally formed with the base 51, but is connected in a detachable manner, in particular in a form-fitting manner. For this purpose, the hollow body 541 of the puncture needle 54 is provided with a projecting catch 543 and the base 51 with a corresponding catch 511, see the exploded sectional view on the right in fig. 4, the hollow body 541 and the base 51 being fixedly connected to one another by means of the catch 543 and the catch 511. Further, a seal ring 57 is preferably provided between the hollow body 541 and the base 51.

Referring to fig. 5, a cross-sectional view of yet another embodiment of an injector head 50 according to the present invention is shown. It differs from fig. 3 in that the hollow body 541 of the puncture needle 54 is constructed integrally with the base 51, while the hollow body 541 and the puncture needle tip 542 are detachably connected, in particular at the opening 56, preferably in a form-fitting manner (see fig. 5, right-hand exploded sectional view). Furthermore, it is conceivable, similarly to the embodiment shown in fig. 5, to modify the embodiment shown in fig. 4, that the hollow body 541 and the piercing needle tip 542 are also detachably connected, in particular at the opening 56, preferably in a form-fitting manner.

Referring to fig. 6, a cross-sectional view of a particular construction of a drug storage tube 60 according to the present invention is shown. The drug storage tube 60 for containing the drug solution 64 may be cylindrical with a front plug 61 on the side near the injector head 50, a rear plug 62 on the side near the pusher 40, and surrounded on the circumferential side by a drug tube wall 63, similar to the current cartridge bottles commonly used for biopharmaceuticals. The drug tube wall 63 may be made of glass or polymer, and it is considered that the drug tube wall 63 is thicker to withstand the high pressure during injection, and the front rubber plug 61 and the rear rubber plug 62 may be made of materials compatible with the drug. With the drug storage tube 60 disposed in the main body 10, the push rod 40 under the action of the pusher 30 can, for example, press a piston against the rear rubber plug 62 and push the rear rubber plug 62 to move axially, thereby squeezing the drug solution 64 contained in the drug storage tube 60. Preferably, the front rubber plug 61 has a recess 611 on the side facing the injector head 50 matching the shape of the puncture needle tip 541, in order to be penetrated by the puncture needle tip 541. Preferably, the rear rubber plug 62 has a recess 621 on the side facing the syringe 50, which is matched with the shape of the puncture needle tip 541, so as to empty the medical fluid 64 contained in the drug storage tube 60 when the push rod 40 pushes the rear rubber plug 62 close to the front rubber plug 61.

Referring to fig. 7, there is shown a needle-less injector 1 according to the present invention in an operating state, wherein the push rod 40 is moved by the piston at the front end thereof by the actuating mechanism 30 to push the rear plug 62 of the drug storage tube 60, thereby squeezing the drug solution 64 contained in the drug storage tube 60, so that it rapidly reaches the injection micro-cavity 52 from the opening 56 in the puncture needle 54 piercing the front plug 61 of the drug storage tube 60, the main passage 54 and is ejected from the injection micro-hole 53.

From the foregoing, those skilled in the art will readily recognize alternative structures to those disclosed as possible and that combinations of the disclosed embodiments can be made to produce new embodiments, which also fall within the scope of the appended claims.

Claims (27)

1. An injector head for a needleless injector, the injector head comprising a base for fixing to the needleless injector, an injection microcavity formed in the base, the front end of the injection microcavity leading to injection micropores formed in the front side of the base for injecting a liquid medicine outwardly, the base being provided at its rear side with a puncture needle projecting rearwardly, characterized in that the puncture needle has a hollow body and a puncture needle tip provided at the end of the hollow body, the cavity of the hollow body forming a main passage communicating with the injection microcavity, the side wall of the hollow body of the puncture needle being provided with at least one opening.

2. The injector head for a needle-free injector according to claim 1, wherein the hollow body is integrally constructed with the base.

3. The injector head for a needleless injector as in claim 1 wherein said hollow body is removably attached to said base.

4. An injector head for a needleless injector as in claim 3 wherein said hollow body is connected to said base in a form-fitting manner.

5. The injector head for a needleless injector according to claim 4, wherein said hollow body is provided with a protruding catch and said base is provided with a corresponding catch, said hollow body and said base being fixedly connected to each other by said catch and said catch.

6. An injector head for a needleless injector as claimed in any of claims 3 to 5 in which a sealing ring is provided between the hollow body and the base.

7. An injector head for a needle-free injector according to any of claims 1 to 3, characterized in that the hollow body is detachably connected to the piercing needle tip.

8. The injector head for a needle-free injector according to claim 7, wherein the hollow body and the piercing tip are connected to each other at the opening.

9. An injector head for a needle-free injector according to claim 7, characterized in that the hollow body is connected in a form-fitting manner to the piercing needle tip.

10. An injector head for a needle-free injector according to any of the preceding claims 1 to 3, characterized in that the piercing tip is free of openings in the piercing direction.

11. The injector head for a needle-free injector according to any of the preceding claims 1 to 3, characterized in that the injection microcavity has a cross-section that tapers towards the injection micropores.

12. The injector head for a needleless injector according to claim 11, wherein said injection microcavity has a tapered cross-section.

13. An injector head for a needleless injector as claimed in any of claims 1 to 3 wherein the primary passageway has a uniform diameter or a non-uniform diameter.

14. An injector head for a needleless injector as claimed in any of claims 1 to 3 in which the mean diameter of the primary passageway is substantially greater than the mean diameter of the injection microcavity.

15. An injector head for a needle-free injector according to any of claims 1 to 3, characterised in that the at least one opening is adjacent the piercing tip.

16. An injector head assembly comprising an injector head and a retaining sleeve adapted to releasably retain the injector head, wherein the injector head is an injector head for a needleless injector according to any of claims 1 to 15.

17. The injector head assembly of claim 16, wherein the retaining sleeve has a radially inwardly extending flange at the forward end and defines an opening therethrough.

18. The injector head assembly of claim 17, wherein the injector head has a profile that mates with the flange.

19. A needleless injector comprising a cylindrical main body and an injector head assembly detachably fixed at the front end of the main body, wherein the main body comprises a front drug storage tube accommodating cavity, a rear pusher accommodating cavity and a transition part between the drug storage tube accommodating cavity and the pusher accommodating cavity, the drug storage tube accommodating cavity is used for accommodating a drug storage tube and is provided with a pusher in the pusher accommodating cavity, the drug storage tube can be placed between the injector head assembly and the pusher in an inner cavity of the main body, the drug storage tube is a cylindrical container for accommodating drug liquid and is provided with a front rubber plug at one side close to the injector head assembly and a rear rubber plug at one side close to the pusher, and the pusher can penetrate through the transition part when axially moved under the action of force of the pusher, Abutting and pushing the rear plug, characterized in that the injection head assembly is an injection head assembly according to any of the preceding claims 16 to 18.

20. A needle-free injector according to claim 19, characterised in that the front part of the plug has a recess on the side facing the injector head which matches the shape of the piercing needle tip.

21. A needleless injector as claimed in claim 19 or claim 20 wherein said pusher comprises an actuator mechanism and a push rod in contact with said actuator mechanism.

22. The needle free injector of claim 21, wherein the rear plug has a recess on a side facing the injector head that matches the shape of the piercing needle tip to facilitate emptying of the drug contained in the drug storage tube when the push rod pushes the rear plug against the front plug.

23. The needle free injector of claim 21, wherein the pushrod has an enlarged diameter end at the end in contact with the actuation mechanism.

24. A needle free injector as claimed in claim 21, characterised in that the push rod is embodied as a piston at the end opposite the actuation mechanism.

25. A needleless injector as claimed in claim 19 or claim 20 wherein the fixing sleeve is secured to the forward end of the body by a screw-thread connection or a snap-fit connection.

26. A needleless injector as claimed in claim 19 or claim 20 wherein the injector head is reusable.

27. A needleless injector as claimed in claim 19 or claim 20 wherein said needleless injector is a pre-filled needleless injector.