CN218220748U

CN218220748U - Syringe needle protection type prefilled syringe

Info

Publication number: CN218220748U
Application number: CN202220613979.XU
Authority: CN
Inventors: 不公告发明人
Original assignee: Shanghai Xinyaopaike Medical Technology Co ltd
Current assignee: Shanghai Xinyaopaike Medical Technology Co ltd
Priority date: 2022-03-21
Filing date: 2022-03-21
Publication date: 2023-01-06
Anticipated expiration: 2032-03-21

Abstract

The utility model belongs to the technical field of embedment syringe in advance, especially, relate to a syringe needle protection type embedment syringe in advance. The utility model discloses an injection cylinder, syringe needle, needle installed part, protection casing unit and needle cover unit have played thereby cladding syringe needle and have avoided the syringe to stab other people's technological effect abandoning the in-process. The utility model has the advantages of it is following: firstly, the needle head is coated by the protective cover, so that the needle head is not exposed to stab other people, and the protective cover is not separated from the needle cylinder while the needle head is exposed; secondly, a plurality of stop hooks are arranged, so that the effect of fixing the stop hooks on the outer ring surface of the needle cylinder is realized when the protective cover is opened, and the stop hooks cannot slide downwards in the injection process; thirdly, a hollow structure is designed on the stop hook, and a cantilever and the stop hook are arranged in the hollow structure to jointly fix the protective cover, so that the stress is uniform; fourthly, the cantilever is provided with a chamfer structure corresponding to the main body part of the injector, so that the process of crossing the convex edge part is smoother, and the phenomenon of blocking is not easy to occur.

Description

Syringe needle protection type prefilled syringe

Technical Field

The utility model belongs to the technical field of embedment syringe in advance, especially, relate to a syringe needle protection type embedment syringe in advance.

Background

The pre-filled syringe is a new type of drug package, and from another point of view, it can be understood as "an injectable drug package". Since the prefilled syringe is also a kind of syringe, there is a risk that the needle of the syringe may hurt people when the syringe is discarded after use, so to solve this problem, there is a device for destroying the needle before discarding in the market, for example, chinese utility model patent with publication number CN210936412U, publication number 2020-07-07 discloses a needle shearing device of an integrated syringe, which includes: the first shearing part is internally defined with a first chamber which extends along the axial direction of the first shearing part and has an open end, the first chamber can accommodate the needle of the syringe and the syringe to pass through, the other end of the first shearing part is provided with a first shearing opening communicated with the first chamber, and the needle and the connecting part can pass through the first shearing opening; the first blade is arranged at the first shearing port; the second shearing part is internally limited with a second cavity which extends along the axial direction of the second shearing part and has an open end, one end of the second cavity is sleeved on the other end of the first shearing part, a driving part is arranged in the second shearing part, and the second shearing part can rotate around the axis of the second shearing part so that the driving part drives the connecting part to stop against the first blade and be broken off by the first blade.

However, such a shearing device has the following disadvantages: firstly, the injection work in the hospital is various, even a nurse is required to go to each ward to complete the injection task, the nurse is required to carry the shearing device, and the nurse cannot guarantee to remember to carry the shearing device at any time; secondly, the needle can fly out with probability in the shearing process, so that the needle is lost and even directly injures others; thirdly, the sheared needle still needs to be discarded, and although the volume of medical waste is greatly reduced and the medical waste can be treated in a centralized manner, the problem that the needle is exposed when discarded is not fundamentally solved, and the centralized treatment is time-consuming and labor-consuming.

In view of the above, there is a need for a prefilled syringe that ensures that the needle is not exposed and does not stick to others when discarded after use.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a syringe needle protection formula embedment syringe in advance, the utility model discloses an injection cylinder, syringe needle, needle installed part, protection casing unit and needle cover unit have played thereby the cladding syringe needle avoid the syringe to stab other people's technological effect abandoning the in-process.

The utility model provides a technical scheme that above-mentioned problem adopted is: a needle head protection type pre-filling and sealing injector comprises an injection needle cylinder, a needle head, a needle mounting part, a protective cover unit and a needle sleeve unit; wherein:

the needle head is mounted on the needle mounting member;

the needle sleeve unit is sleeved on the needle head and part of the needle mounting piece;

the protective cover unit is sleeved on the needle sleeve unit and part of the injection needle cylinder;

the protective cover unit comprises a protective cover main body and a front clamping piece arranged on the protective cover main body;

the needle mounting piece is arranged at the far end of the injection needle cylinder, and a groove is formed between the needle mounting piece and the injection needle cylinder and used for clamping the front clamping piece.

The further preferred technical scheme is as follows: the protective cover unit also comprises a rear clamping piece on the protective cover main body; wherein:

the proximal end of the rear engaging member axially jacks up the distal end of the maximum outer diameter of the needle mounting member.

The further preferred technical scheme is as follows: the protective cover unit also comprises a wide stop hook; wherein:

the far end of the wide stop hook is connected with the near end of the protective cover main body, and the near end of the wide stop hook is clamped in the groove.

The further preferred technical scheme is as follows: the protective cover unit also comprises a cantilever part and a cantilever opening; wherein:

the cantilever opening is arranged on the wide stop hook;

the cantilever part is arranged on the inner side surface of the cantilever port.

The further preferred technical scheme is as follows: the cantilever opening extends distally onto a portion of the shield body.

The further preferred technical scheme is as follows: the protective cover unit also comprises a narrow stop hook; wherein:

the distal end of the narrow stop hook is connected with the proximal end of the protective cover main body, and the proximal end of the narrow stop hook is clamped with one side of the proximal end of the maximum outer diameter position of the needle mounting piece;

the narrow stop hook is arranged between the two wide stop hooks.

The further preferred technical scheme is as follows: the wide stop hooks are symmetrically arranged.

The further preferred technical scheme is as follows: the narrow stop hooks are symmetrically arranged.

The further preferred technical scheme is as follows: the cantilever part comprises a cantilever elastic part and a cantilever clamping part; wherein;

the far end of the cantilever elastic part is arranged on the inner side surface of the cantilever port;

the far end of the cantilever clamping piece is arranged on the near end of the cantilever elastic piece;

when the protective cover main body is closed, the near end of the cantilever clamping piece abuts against one side of the near end of the position with the largest outer diameter of the needle mounting piece.

The further preferred technical scheme is as follows: the cantilever part further comprises a near-end chamfer; wherein:

the proximal chamfer is disposed at a proximal end of the cantilever snap, such that the cantilever snap passes over a maximum outer diameter of the needle mount when the shield body is open.

The further preferred technical scheme is as follows: the cantilever part further comprises a distal chamfer; wherein:

the distal chamfer is disposed at a distal end of the cantilever snap, such that the cantilever snap passes over a maximum outer diameter of the needle mount when the shield body is closed.

The further preferred technical scheme is as follows: the needle mount comprises a fin member; wherein:

when the protective cover main body is closed, the far end of the convex rib piece is clamped with the cantilever clamping piece, and the near end of the convex rib piece is clamped with the wide stop hook and the narrow stop hook.

The further preferred technical scheme is as follows: the needle mount comprises a rib chamfer; wherein:

the bead chamfer is disposed on the bead distal end, when the shield body is opened, the cantilever snap-fit exceeds the bead.

The needle head protection type pre-filled and sealed syringe component also comprises a sealing plug and a push rod inserted and arranged on the sealing plug.

A method of installing components of a needle-shielded pre-filled syringe, comprising the steps of:

the first step is as follows: installing the needle hub unit into the shield body;

the second step is that: mounting the shield body and needle hub unit on the needle mount;

the third step: installing the sealing plug in the syringe barrel;

the fourth step: mounting the push rod on the sealing plug.

A method of drug encapsulation of a component of a needle-shielded pre-encapsulated syringe, comprising the steps of:

1. placing the opening of the injection syringe upwards and vertical to a horizontal plane, and filling quantitative liquid medicines into the injection syringe;

2. installing the sealing plug in the injection syringe through a sleeve, wherein the maximum outer diameter of the sleeve is smaller than the minimum inner diameter of the injection syringe;

3. mounting the push rod on the sealing plug.

The utility model has the advantages of it is following:

first, but utilize axial activity's protection casing to carry out the cladding to the syringe needle for the syringe needle can not expose and stab other people, and through the slip of protection casing, can expose the syringe needle in the injection process, the protection casing can not break away from with the cylinder, and the injection of being convenient for is accomplished the back and is directly pushed back, and cladding syringe needle is then abandoned again.

And secondly, a plurality of stopping hooks are arranged at the near end of the protective cover, so that the stability of the protective cover after the protective cover is fixed is improved, and when the protective cover is opened, the stopping hooks are tightly attached to the surface of the needle cylinder, so that the protective cover is fixed on the outer annular surface of the needle cylinder, and cannot slide downwards in the injection process.

Thirdly, a hollow structure is designed on the stop hook, and a cantilever and the stop hook are arranged in the hollow structure to jointly fix the protective cover, so that the stress is uniform.

Fourthly, the cantilever is provided with a chamfer structure corresponding to the main body part of the injector, so that the process of crossing the convex edge part is smoother, and the phenomenon of blocking is not easy to occur.

Drawings

Fig. 1 is an exploded view of the overall structure of the middle prefilled syringe of the present invention.

Fig. 2 is a schematic structural view of the protective cover unit installed on the needle mounting member when the middle needle sleeve unit is not coated on the needle head.

Fig. 3 is a schematic structural view of the needle guard unit installed on the needle mounting member when the middle needle guard unit is coated on the needle head.

Fig. 4 is a schematic structural view of the middle protective cover unit of the present invention.

Fig. 5 is a cross-sectional view of fig. 2 cut along line AA.

Fig. 6 is a cross-sectional view of fig. 3 cut along line BB.

Fig. 7 is an enlarged view of region a in fig. 5.

In the drawings, the reference numerals designate the following components: the syringe 11, the needle head 12, the needle mount 1, the shield unit 2, the needle sheath unit 3, the rib 101, the rib chamfer 102, the shield body 201, the wide stop hook 202, the cantilever member 203, the cantilever mouth 204, the narrow stop hook 205, the cantilever elastic member 203a, the cantilever engaging member 203b, the proximal chamfer 203c and the distal chamfer 203d.

Detailed Description

Defining:

1. a far end: the finger is directed towards one end of the needle.

2. Proximal end: the finger is far away from one end of the needle head.

3. Axis: refers to an object having a regular cross-section through a vertical line passing through its centroid.

4. Opening direction: refers to the direction in which the needle or needle hub unit can be exposed during operation.

5. Closing direction: refers to the direction in which the needle or needle hub unit can be covered during operation.

6. Sleeving: refers to the act of mounting the first component on the outer surface of the second component when the inner diameter of the first component is greater than the outer diameter of the second component.

7. Setting: refers to any means for joining two parts together by bonding, snapping, welding, screwing, placing, etc.

8. Jacking: the first finger component exerts a force on the second component, so that the second component moves towards the direction opposite to the position of the first component.

The following description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention.

Example (b): as shown in fig. 1 to 7, a needle-protected prefilled syringe comprises a syringe barrel 11, a needle 12, a needle mounting member 1, a shield unit 2 and a needle sheath unit 3; wherein:

the needle head 12 is mounted on the needle mount 1;

the needle sleeve unit 3 is sleeved on the needle head 12 and part of the needle mounting piece 1;

the protective cover unit 2 is sleeved on the needle guard unit 3 and part of the injection needle cylinder 11;

the protective cover unit 2 comprises a protective cover main body 201 and a front clamping piece arranged on the protective cover main body 201;

the needle mount 1 is disposed at the distal end of the syringe barrel 11, and a groove is formed between the needle mount and the syringe barrel 11 for engaging the front engaging member.

In this embodiment, the injection needle cylinder 11 and the needle head 12 constitute a common injector device in the prior art, in order to facilitate pre-filling of a medicine, a push rod is not arranged in the injection needle cylinder 11, and after the medicine is filled by a downstream manufacturer, a proper push rod is added according to the specification of the needle cylinder 11 by itself to ensure sealing performance, the whole shield unit 2 is firstly sleeved on the needle guard unit 3, then the needle guard unit 3 and the needle head 12 are covered together in the installation process, and a part of the shield unit 2 is sleeved on the needle installation member 1.

After the medicine is filled, the using method of the syringe comprises the following steps:

a first step of pushing the protective cover unit 2 to the near end to expose the needle sleeve unit 3;

secondly, removing the needle sleeve unit 3 to expose the needle head 12;

thirdly, pushing the push rod to perform injection operation;

fourth, the shield unit 2 is pushed distally, recoating the needle 12, and discarded.

In addition, preferably, the shield main body 201 and the front engaging member are main components of the shield unit 2, the shield main body 201 is disposed at one side of the distal end of the shield unit 2, the front engaging member is disposed at one side of the proximal end of the shield unit 2, and the minimum inner diameter of the front engaging member is smaller than the maximum outer diameter of the needle mounting member 1 and the injection syringe 11, so that in the fourth step, the front engaging member can make the shield main body 201 stay at a position covering the needle head 12 by engaging with the groove, thereby achieving a protective effect.

Further, the front engaging piece can be expanded so that the minimum inner diameter is larger than the maximum outer diameter of the syringe barrel 11, and thus, in the first step, the protector body 201 slides proximally, thereby releasing the covering action of the needle 12 and performing the injection operation.

The protective cover unit 2 further comprises a rear clamping piece on the protective cover main body 201; wherein

The proximal end of the rear engaging member axially abuts the distal end of the needle mount 1 at the maximum outer diameter.

In this embodiment, the groove is a naturally formed feature of the maximum outer diameter of the needle mount 1 and the syringe 11, when the front engaging member is engaged in the groove, the distal end thereof axially pushes up the proximal end of the maximum outer diameter of the needle mount 1, and the proximal end of the rear engaging member axially pushes up the distal end of the maximum outer diameter of the needle mount 1, so that the front engaging member and the rear engaging member cooperate to clamp the maximum outer diameter of the needle mount 1, thereby firmly fixing the shield body 201 at the fourth step without relying on the force of the front engaging member engaged in the groove.

In addition, in the first step, in order to smoothly push the shield main body 201, the rear engaging member is manually expanded to release the engagement with the maximum outer diameter of the needle mount 1, so that the shield main body 201 is smoothly pushed.

Furthermore, preferably, when the needle guard unit 3 exists, the needle guard unit 3 radially jacks up the rear engaging member to release the engaging state with the maximum outer diameter of the needle mounting member 1, which is advantageous in that when the needle guard unit 3 exists, the shield main body 201 can be pushed only by a pushing force without manual expansion, and when the needle guard unit 3 is removed in the fourth step, the rear engaging member is engaged with the maximum outer diameter of the needle mounting member 1 again, the position of the shield main body 201 cannot be adjusted only by the pushing force, so that the needle C is protected.

The protective cover unit 2 further comprises a wide stop hook 202; wherein:

the distal end of the wide stop hook 202 is connected with the proximal end of the protective cover main body 201, and the proximal end of the wide stop hook 202 is clamped in the groove.

In this embodiment, the wide stop hook 202 is an expression of the front engaging member, and has an engaging block extending in the radial direction at the proximal end thereof for engaging in the groove, that is, for axially pushing up the proximal end surface of the needle mount 1 at the maximum outer diameter, and the wide stop hook 202 itself has elasticity and can be expanded in the inner diameter by bending so as to go out of the groove and release the engaged state.

The protective cover unit 2 further comprises a cantilever part 203 and a cantilever opening 204; wherein:

the cantilever port 204 is arranged on the wide stop hook 202;

the cantilever part 203 is mounted on the inner side of the cantilever opening 204.

In this embodiment, the cantilever member 203 is one of the expressions of the rear engaging member, the cantilever mouth 204 is disposed near the distal end of the wide stop hook 202, and the cantilever member 203 is disposed on the inner side surface of the distal end of the cantilever mouth 204 and extends toward the proximal end, so that the proximal end of the cantilever mouth 204 and the proximal end of the wide stop hook 202 form a holding member for holding the needle mount 1 at the maximum outer diameter for engaging.

In addition, through setting up cantilever mouth 204 installation cantilever part 203 makes cantilever part 203 with wide ending position hook 202 integration, in fact when preparing, cantilever part 203 is promptly in the wide ending position hook 202 integrative preparation forms, has just not had the circumstances of cantilever part 203 perk, and such benefit lies in that the nurse can grasp with the similar gesture of taking the pencil when the injection protection casing unit 2, and the comfort level of nurse's use has been improved greatly to this kind of design of no edges and corners, compares in the protruding product of other cantilevers on the market, and use experience is better.

The cantilever opening 204 extends distally over a portion of the shield body 201.

In this embodiment, the extension of the cantilever opening 204 provides a larger internal space, allowing the cantilever member 203 with a longer radial length to be mounted, which in fact increases the radial expansion range of the cantilever member 203, making it easier to pass the maximum outer diameter of the needle mount 1 when opening the shield body 201.

The protective cover unit 2 further comprises a narrow stop hook 205; wherein:

the distal end of the narrow stop hook 205 is connected to the proximal end of the protective cover main body 201, and the proximal end of the narrow stop hook 205 is clamped with one side of the proximal end of the maximum outer diameter part of the needle mounting piece 1;

the narrow stop hook 205 is disposed between the two wide stop hooks 202.

In this embodiment, the narrow stop hook 205 actually functions the same as the wide stop hook 202, except that the cantilever 203 is not mounted on the narrow stop hook 205, and only functions to limit the radial movement of the shield main body 201 toward the distal end, but this design makes full use of the vacant positions between the wide stop hooks 202.

In addition, the two wide stop hooks 202 are generally disposed at the proximal end of the shield main body 201, and the narrow stop hooks 205 disposed between the wide stop hooks 202 can provide a balanced force, i.e. the wide stop hooks 202 and the cantilever member 203 clamp the maximum outer diameter of the needle mount 1, thereby preventing the shield main body 201 from shaking.

The wide stop hooks 202 are symmetrically arranged.

The narrow stop hooks 205 are symmetrically arranged.

In this embodiment, the wide stop hook 202 and the narrow stop hook 205 are symmetrically designed, so that the shield unit 2 is more beautiful, and the engaging force is balanced to reduce the shaking of the shield main body 201.

The cantilever member 203 comprises a cantilever elastic member 203a and a cantilever engaging member 203b, wherein;

the far end of the cantilever elastic piece 203a is arranged on the inner side surface of the cantilever opening 204;

the distal end of the cantilevered snap member 203b is disposed on the proximal end of the cantilevered resilient member 203 a;

when the shield body 201 is closed, the proximal end of the cantilever engaging member 203b abuts against the proximal side of the needle mount 1 at the maximum outer diameter.

In this embodiment, the cantilever member 203 is composed of two parts, the first part is a cantilever elastic member 203a disposed on the cantilever mounting opening 204 and radially bent toward the shield body 201, and the cantilever engaging member 203b is disposed on the end face of the distal end of the cantilever elastic member 203a, so that the end face of the cantilever engaging member 203b can be abutted against the distal end face at the maximum outer diameter of the needle mount 1, and is used for ejecting the distal end face at the maximum outer diameter of the needle mount 1 when closed and generating a friction force restriction effect on the surface of the syringe body a when opened.

The cantilever member 203 further comprises a proximal chamfer 203c; wherein:

the proximal chamfer 203c is provided proximal to the cantilevered engagement member 203b to allow the cantilevered engagement member 203b to clear the maximum outer diameter of the needle mount 1 when the shield body 201 is open.

In this embodiment, when the shield body 201 is pushed axially in the first step, the proximal chamfer 203c axially pushes up the distal end surface of the maximum outer diameter of the needle mount 1, and a radial force is generated to drive the cantilever elastic member 203a to expand radially, so as to pass over the maximum outer diameter of the needle mount 1, and the shield body 201 continues to move axially.

The cantilever member 203 further comprises a distal chamfer 203d; wherein:

the distal chamfer 203d is provided at the distal end of the cantilevered engagement member 203b to allow the cantilevered engagement member 203b to clear the maximum outer diameter of the needle mount 1 when the shield body 201 is closed.

In this embodiment, when the fourth step pushes the shield main body 201 axially, the distal chamfer 203d axially jacks up the proximal end surface of the maximum outer diameter of the needle mounting member 1 to drive the cantilever elastic member 203a to expand radially, so as to pass over the maximum outer diameter of the needle mounting member 1, and the cantilever engaging member 203b is engaged with the distal end of the maximum outer diameter of the needle mounting member 1.

The needle mount 1 comprises a fin 101, wherein:

when the shield body 201 is closed, the distal end of the rib 101 engages the cantilevered engagement members 203b, and the proximal end of the rib 101 engages the wide stop hook 202 and the narrow stop hook 205.

In this embodiment, the rib 101 is a representation of the maximum outer diameter of the needle mount 1, and functions to lift the distal end of the rib from the cantilever latch 203b, lift the proximal end of the rib from the wide stop hook 202 and the narrow stop hook 205, and form an annular groove with the syringe barrel 11 for engaging the proximal end latch of the wide stop hook 202 and the narrow stop hook 205.

Further, the rib 101 is formed so as not to be disengaged from the shield main body 201 regardless of the rotation thereof once it is caught.

The needle mount 1 comprises a rib chamfer 102, wherein:

the rib chamfer 102 is provided on the distal end of the rib 101 to allow the cantilevered engagement member 203b to clear the rib 101 when the shield body 201 is opened.

In this embodiment, the chamfer slope of the rib chamfer 102 is the same as the chamfer slope of the distal chamfer 203d, such that in the first step, the distal chamfer 203d abuts the rib chamfer 102, thereby increasing the radial expansion force of the cantilever spring 203a and facilitating the cantilever 203 to pass over the rib 101.

The needle head protection type pre-filled and sealed syringe component also comprises a sealing plug and a push rod which is inserted and arranged on the sealing plug.

In this embodiment, a locking groove for installing one end of the pushing rod is left behind the sealing plug.

the first step is as follows: the needle hub unit 3 is installed in the shield body 2;

the second step is that: mounting the shield body 2 and needle hub unit 3 on the needle mount 1;

the third step: mounting the sealing plug in the syringe barrel 11;

the fourth step: mounting the push rod on the sealing plug.

In this embodiment, the protection cover main body 2 and the needle hub unit 3 are mounted together in a simple manner, so as to be conveniently applied to the assembly line type mounting process.

A method of drug potting of components of a needle-protected pre-filled syringe comprising the steps of:

1. placing the opening of the injection needle cylinder 11 upwards and vertical to the horizontal plane, and filling quantitative liquid medicines into the injection needle cylinder 11;

2. the sealing plug is arranged in the injection syringe 11 through a sleeve, and the maximum outer diameter of the sleeve is smaller than the minimum inner diameter of the injection syringe;

3. mounting the push rod on the sealing plug.

In this embodiment, after the sealing plug is installed in the injection syringe 11, no air is left in the injection syringe 11, and an operator can directly perform injection.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention within the knowledge of those skilled in the art. These are non-inventive modifications, which are intended to be protected by patent laws within the scope of the appended claims.

Claims

1. A needle head protection type pre-filling and sealing injector comprises an injection needle cylinder (11) and a needle head (12), and is characterized by further comprising a needle mounting piece (1), a protective cover unit (2) and a needle sleeve unit (3); wherein:

the needle head (12) is mounted on the needle mount (1);

the needle sleeve unit (3) is sleeved on the needle head (12) and part of the needle mounting piece (1);

the protective cover unit (2) is sleeved on the needle sleeve unit (3) and part of the injection needle cylinder (11);

the protective cover unit (2) comprises a protective cover main body (201) and a front clamping piece arranged on the protective cover main body (201);

the needle mounting piece (1) is arranged at the far end of the injection needle cylinder (11), and a groove is formed between the needle mounting piece and the injection needle cylinder (11) and used for clamping the front clamping piece.

2. A needle-protected pre-filled and sealed syringe according to claim 1, characterised in that the shield unit (2) further comprises a rear catch on the shield body (201); wherein:

the proximal end of the rear clamping piece axially jacks up the distal end of the maximum outer diameter position of the needle mounting piece (1).

3. A needle-protected pre-filled and sealed syringe according to claim 1, characterised in that said protective cover unit (2) further comprises a wide stop hook (202); wherein:

the far end of the wide stop hook (202) is connected with the near end of the protective cover main body (201), and the near end of the wide stop hook (202) is clamped in the groove.

4. A needle-shielded pre-filled and sealed syringe according to claim 3, characterized in that the shield unit (2) further comprises a cantilever member (203), and a cantilever mouth (204); wherein:

the cantilever opening (204) is arranged on the wide stop hook (202);

the cantilever part (203) is arranged on the inner side surface of the cantilever opening (204).

5. A needle-protected pre-filled and sealed syringe according to claim 4, characterised in that the cantilever port (204) extends distally to part of the shield body (201).

6. A needle-shielded pre-filled and sealed syringe according to claim 4, characterized in that said protective cover unit (2) further comprises a narrow stop hook (205); wherein:

the far end of the narrow stop hook (205) is connected with the near end of the protective cover main body (201), and the near end of the narrow stop hook (205) is clamped with one side of the near end of the maximum outer diameter position of the needle mounting piece (1);

the narrow stop hook (205) is arranged between the two wide stop hooks (202).

7. A needle-protected pre-filled and sealed syringe according to claim 3, characterised in that the wide stop hooks (202) are symmetrically arranged.

8. A needle-shielded pre-filled and sealed syringe according to claim 6, characterised in that the narrow stop hooks (205) are symmetrically arranged.

9. The needle-shielded pre-filled and sealed syringe according to claim 6, wherein the cantilever member (203) comprises a cantilever elastic member (203 a) and a cantilever snap-fit member (203 b); wherein;

the far end of the cantilever elastic part (203 a) is arranged on the inner side surface of the cantilever opening (204);

the far end of the cantilever clamping piece (203 b) is arranged on the near end of the cantilever elastic piece (203 a);

when the protective cover main body (201) is closed, the near end of the cantilever clamping piece (203 b) abuts against the near end side of the position with the largest outer diameter of the needle mounting piece (1).

10. A needle-shielded pre-filled and sealed syringe according to claim 9, characterized in that said cantilever member (203) further comprises a proximal chamfer (203 c); wherein:

the proximal chamfer (203 c) is provided proximal to the cantilever engagement member (203 b) to allow the cantilever engagement member (203 b) to pass over the maximum outer diameter of the needle mount (1) when the shield body (201) is open.

11. A needle-shielded pre-filled and sealed syringe according to claim 9, characterized in that said cantilever member (203) further comprises a distal chamfer (203 d); wherein:

the distal chamfer (203 d) is provided at the distal end of the cantilevered engagement member (203 b) to allow the cantilevered engagement member (203 b) to pass over the maximum outer diameter of the needle mount (1) when the shield body (201) is closed.

12. A needle-shielded pre-filled and sealed syringe as claimed in claim 9, characterized in that the needle mount (1) comprises a fin (101); wherein:

when the protective cover main body (201) is closed, the far end of the rib piece (101) is clamped with the cantilever clamping piece (203 b), and the near end of the rib piece (101) is clamped with the wide stop hook (202) and the narrow stop hook (205).

13. A needle-shielded pre-filled and sealed syringe according to claim 12, characterized in that the needle mount (1) comprises a rib chamfer (102); wherein:

the rib chamfer (102) is provided on the distal end of the rib (101) to allow the cantilevered engagement member (203 b) to clear the rib (101) when the shield body (201) is opened.