WO2023217041A1

WO2023217041A1 - Needle tip protection-type pre-fillable injection device, assembly, installation method for assembly, and method for using assembly

Info

Publication number: WO2023217041A1
Application number: PCT/CN2023/092552
Authority: WO
Inventors: 郭融
Original assignee: 上海新耀湃科医疗科技股份有限公司
Priority date: 2022-05-07
Filing date: 2023-05-06
Publication date: 2023-11-16
Also published as: CN114733007A

Abstract

A needle tip protection-type pre-fillable injection device, an assembly, an installation method for an assembly, and a method for using an assembly. The injection device comprises an injection syringe (11), a needle mounting member (12), an injection needle (13), and a needle protective sleeve (14); the needle mounting member (12) is arranged on the distal end of the injection syringe (11), and the needle mounting member (12) has a through hole (12a) which is in communication with the inside of the injection syringe (11); the injection needle (13) is mounted on the needle mounting member (12) by means of insertion into the through hole (12a); the needle protective sleeve (14) is sleeved onto the needle mounting member (12) and completely covers the injection needle (13); the injection syringe (11), the needle mounting member (12), the injection needle (13), and the needle protective sleeve (14) share a common axis. The present invention further comprises a protective cover unit (1), the protective cover unit (1) comprising: a protective cover (101) upon which sliding openings (102) are arranged, said cover obstructing the injection needle (13); and the protective cover unit (1) further comprises a flexible hook unit (2), the flexible hook unit (2) comprising flexible hooks (202) that extend into the sliding openings (102). By means of a protective cover unit sleeved on the needle mounting member on the injection syringe, and the flexible hook unit that fixes the protective cover unit, the present invention achieves the technical effect of conveniently and effectively covering the needle tip after injection.

Description

Needle-guarded prefilled syringes, components, how to install components, how to use components

Technical field

The invention belongs to the technical field of prefilled syringes, and in particular relates to needle-protected prefilled syringes, components, installation methods of the components, and usage methods of the components.

Background technique

A syringe is a common medical device that mainly uses a needle to extract or inject gas or liquid. This process is called injection. The syringe consists of a syringe with a small hole at the front and a matching piston rod. It is used to inject a small amount of The liquid or gas is injected into the area that is inaccessible by other methods, and the liquid or gas is squeezed out when the core rod is pushed in. However, disposable syringes have poor stability and need to be filled with medicine before use. It is very inconvenient to squeeze out the air after filling. Therefore, a pre-filled syringe that fills the medicine in advance and injects directly after opening was developed and popularized. Nowadays, , which was widely used in vaccination during the new coronavirus pneumonia epidemic and showed high market value.

However, existing prefilled syringes are often discarded randomly after use, and the needle is exposed, which is very dangerous. To solve the problem of needle exposure after discarding the syringe, nurses often put the removed needle protective cover back on. However, this has many disadvantages. On the one hand, the needle protective cover is customized for the needle and has a small opening. It is difficult to reinsert it after it is pulled out. On the other hand, the needle can easily stick to the nurse's hand during the reinsertion process, causing harm to medical staff. Infection can easily lead to further spread of the epidemic.

Therefore, to sum up, there is an urgent need for a prefilled syringe that can conveniently and effectively cover the needle after injection to prevent the needle from hurting people.

Contents of the invention

The object of the present invention is to provide a needle-protected pre-filled syringe, an assembly, an installation method of the assembly, and a method of using the assembly. The present invention uses a protective cover unit that is sleeved on the needle mounting member on the injection syringe, and fixes the protective cover unit. The elastic hook unit has the technical effect of conveniently and effectively covering the needle after injection.

The technical solution adopted by the present invention to solve the above problems is: a needle-protected pre-filled syringe, which includes an injection syringe, a needle mounting piece, an injection needle and a needle protective cover; wherein:

The needle mounting member is disposed at the distal end of the injection syringe. The needle mounting member has a through hole that communicates with the inside of the injection syringe. The injection needle is installed on the needle by inserting into the through hole. On the mounting piece, the needle protective sleeve is sleeved on the needle mounting piece and completely covers the injection needle, and the injection syringe, the needle mounting piece, the injection needle and the needle protective sleeve have a common axis;

A protective cover unit is also included, and the protective cover unit includes:

A protective cover for the sliding port is provided on it to block the injection needle;

It also includes an elastic hook unit, and the elastic hook unit includes an elastic hook arranged in the sliding opening.

The protective cover unit also includes an elastic plate. The elastic plate is cantilevered in the sliding port, and the proximal end has a tendency to retract inward along the radial direction of the protective cover.

The proximal end of the elastic plate has a proximal stop surface, which is used to push up the elastic hook when the protective cover is closed, thereby locking the protective cover.

A distal stop surface is provided on the inside of the elastic plate, which is used to push up the elastic hook when the protective cover is opened, thereby locking the protective cover.

The elastic hook includes a radial plate, and the distal end of the radial plate is provided with a closing stop surface for lifting the proximal stop surface.

The elastic hook also includes an axial plate, and the proximal end of the axial plate is provided with an opening stop surface for pushing up the distal stop surface.

The proximal end of the axial plate expands radially outward along the protective cover. When the distal stop surface is pushed up, the elastic plate is pressed radially inward or pulled outward along the protective cover. The opening stop surface of the axial plate and the distal stop surface are separated from the lifted state.

A protruding block is provided on the inner surface of the proximal side of the elastic plate. When the needle protective cover is sleeved on the needle mounting member, the protruding block is pushed radially outward along the protective cover so that the The proximal stop surface on the elastic plate and the closing stop surface on the radial plate are released from the pushing state.

The proximal end of the protruding block has an opening guide surface. When the protective cover slides toward the proximal end, it is used to push up the axial plate of the elastic hook, so that the elastic hook crosses the protruding block.

The raised block also includes a closing guide surface, which is used to push up the axial plate of the elastic hook when the protective cover slides toward the distal end, so that the elastic hook passes over the raised block.

The protective cover unit further includes an expansion slot provided at the proximal end of the protective cover for expansion of the proximal end of the protective cover.

The protective cover unit also includes a guide slope provided at the proximal end of the protective cover for pushing up the axial plate of the elastic hook.

An assembly of the needle-protected pre-filled syringe, including a push rod and a piston; wherein:

The push rod is arranged on the piston;

The piston is installed in the injection syringe and used to push the medicinal liquid through the injection needle when the push rod is pushed in the distal direction.

A method for installing components of a needle-protected prefilled syringe, including the following steps:

S1. Install the needle protective sleeve into the protective cover along the axial direction;

S2. Sleeve the protective cover with the needle protective cover on the needle mounting piece along the axial direction;

S3. Push the piston into the injection syringe;

S4. Set the push rod on the piston.

A method for using components of a needle-protected prefilled syringe, including the following steps:

S1. Move the protective cover axially along the proximal direction of the injection syringe until the back side of the elastic hook contacts the distal side of the sliding port, thereby exposing the needle protective cover;

S2. Open the needle protective cover to expose the injection needle;

S3. Carry out injection operation;

S4. After the injection operation is completed, move the protective cover axially along the distal direction of the injection syringe until one side of the elastic hook hooks the proximal side of the sliding port, thereby completely covering the injection needle.

The invention has the following advantages:

First, it is easy to install and has a simple structure. During use, you only need to slide the protective cover along the injection syringe to open the injection and close it for disposal;

Second, an elastic hook is provided to hook with the side of the sliding port to fix the protective cover. The fixing effect is good and the protective cover is not easy to disengage from the engagement state;

Third, an elastic plate is provided. The elastic plate has a stop surface that snaps together with the elastic hook to fix the protective cover in an open state to facilitate the nurse to inject;

Fourth, after the nurse completes the injection, she can use two fingers to pinch the elastic plate to disengage the stop surface and the elastic hook, so that the protective cover is ejected towards the needle to close. The pinch-to-close method is also suitable for nurses with shorter fingers. Can be operated with one hand;

Fifth, when the needle protective cover covers the injection needle, the elastic plate and the elastic hook are released from the engagement state, allowing the nurse to easily open the protective cover and directly inject.

Description of the drawings

Figure 1 is a schematic structural diagram of an injection needle covered with a needle protective sleeve according to the present invention, and a protective cover unit and an elastic hook unit are installed on the injection syringe.

Figure 2 is a schematic structural diagram of the invention in which the needle protective sheath covers the injection needle and the elastic hook unit is installed on the injection syringe barrel.

Figure 3 is a schematic structural diagram of an elastic hook unit installed on the injection syringe of the present invention.

Figure 4 is a schematic structural diagram of a protective cover unit and an elastic hook unit installed on the injection syringe of the present invention.

Figure 5 is an exploded schematic diagram of the prefilled syringe in the present invention.

FIG. 6 is a schematic cross-sectional structural diagram along line A-A in FIG. 4 .

Figure 7 is an enlarged structural diagram of the elastic hook in Figure 6.

FIG. 8 is an enlarged structural diagram of the injection needle in FIG. 6 .

Figure 9 is a schematic structural diagram of the elastic hook in the present invention.

Figure 10 is a schematic structural diagram of the elastic hook from another side of the present invention.

Figure 11 is a schematic structural diagram of the protective cover unit in the present invention.

Figure 12 is a schematic structural diagram of the protective cover unit in the present invention from another side.

Figure 13 is a schematic structural diagram of the elastic plate in the present invention.

In the drawings, the components represented by each number are as follows: protective cover unit 1, elastic hook unit 2, injection syringe 11, needle mounting piece 12, injection needle 13, needle protective cover 14, protective cover 101, sliding port 102, elastic Plate 103, expansion groove 104, guide slope 105, elastic hook 202, proximal stop surface 103a, distal stop surface 103b, protruding block 103c, opening guide surface 103d, closing guide surface 103e, stop groove 201a, Radial plate 202a, axial plate 202b, closing stop surface 202c, opening stop surface 202d, through hole 12a.

Implementation

definition

1. Distal end: refers to the end far away from the drug injection port of the injection syringe.

2. Proximal end: refers to the end facing the drug injection port of the injection syringe.

3. Axis: refers to an object with a circular cross-section, the vertical line through the center of the circle.

4. Open: refers to the state of exposing the syringe needle or syringe needle and protective cover.

5. Closed: refers to the state of covering the syringe needle or syringe needle and protective sheath.

6. Setting: refers to any method used to arrange and combine two parts together through bonding, snapping, welding, screwing, placing, etc.

7. Pushing up: means that component one exerts force on component two, causing the component two to move or deform in the opposite direction to the position of component one.

The following descriptions are only preferred embodiments of the present invention and do not limit the scope of the present invention.

Embodiment: As shown in Figures 1-13, a needle-protected pre-filled syringe includes an injection syringe 11, a needle mounting part 12, an injection needle 13 and a needle protective cover 14; wherein:

The needle mounting member 12 is disposed at the distal end of the injection syringe 11. The needle mounting member 12 has a through hole 12a, which communicates with the inside of the injection syringe 11. The injection needle 13 is inserted into the through hole 12a. is installed on the needle mounting part 12, the needle protective cover 14 is sleeved on the needle mounting part 12 and completely covers the injection needle 13, the injection syringe 11, the needle mounting part 12, The injection needle 13 and the needle protective cover 14 have a common axis;

It also includes a protective cover unit 1, which includes:

A protective cover 101 with a sliding port 102 is provided on it to block the injection needle 13;

An elastic hook unit 2 is also included. The elastic hook unit 2 includes an elastic hook 202 disposed in the sliding opening 102 .

In this embodiment, the injection syringe 11, the needle mounting member 12, the injection needle 13 and the needle protective cover 14 are all necessary components of the syringe in the prior art to realize the filling and injection functions of medicines, so The installation method of the elastic hook unit 2 and the protective cover unit 1 is:

1. The elastic hook unit 2 is installed on the needle mounting member 12, and the hook bending direction is toward the proximal end of the injection syringe 11;

2. When the protective cover 101 of the protective cover unit 1 is sleeved and installed on the needle mounting member 12, it is sleeved on the elastic hook 202 of the elastic hook unit 2 through deformation, and will pass over the elastic hook 202. After that, the sliding opening 102 is placed on the elastic hook 202 .

The elastic hook 202 slides into the sliding port 102 during the socketing process, and hooks the proximal side of the sliding port 102, thereby achieving a blocking effect on the sliding of the protective cover 101 in the distal direction. .

After the installation is completed, the above components are handed over to the downstream manufacturer for filling of drugs. The drugs are filled from the drug injection port of the injection syringe 11, and then a push rod is installed on the injection syringe 11 through the drug injection port. and injection plunger to complete the pre-filling of the syringe.

In addition, it should be noted that the needle protective sheath 14 uses the existing pre-potted needle sheath materials and shapes that have been standardized and produced, instead of non-standard special-shaped protective caps. The advantages are:

1. Do not change user usage habits;

2. There is no need to re-evaluate the chemical compatibility of the rubber protective cap, which greatly reduces the project development cycle and product registration cycle;

3. Enhance customer confidence.

The method of using the prefilled syringe is:

1. Move the protective cover 101 axially along the proximal direction of the injection syringe 11 until the back side of the elastic hook 202 contacts the distal side of the sliding port 102, thereby exposing the needle protective cover. 14;

2. Open the needle protective cover 14 to expose the injection needle 13;

3. Carry out injection operations;

4. After the injection operation is completed, move the protective cover 101 axially along the distal direction of the injection syringe 11 until one side of the elastic hook 202 hooks the proximal side of the sliding port 102, thereby completely covering the housing. The injection needle 13.

The installation method of the prefilled syringe is as follows:

S1. Install the needle protective sleeve 14 into the protective cover 101 along the axial direction;

S2. Connect the protective cover 101 with the needle protective cover 14 to the needle mounting member 12 in the axial direction;

S3. Push the piston into the injection syringe 11;

S4. Set the push rod on the piston.

In this embodiment, the needle protective cover 14 is first installed in the protective cover 101, which facilitates the automated assembly of syringe components, simplifies the production line process, reduces the cost of the component installation process, and further improves market competitiveness.

It should be noted that the elastic hook 202 may be located at a part of the injection syringe 11 , a part of the needle mounting member 12 , or between the injection syringe 11 and the needle mounting member 12 part in between.

In addition, when the syringe leaves the factory, a light inspection will be performed on the syringe. The "light inspection" is to check whether the filling and plugging of the syringe is qualified through manual observation through the syringe. Most of the integrated protective covers on the market will affect this. A process, for example, the Chinese utility model with the announcement number CN214911888U and the announcement date of 2021-11-30 discloses a syringe needle protection device and a safety syringe, including a protective outer jacket, an installed inner sleeve, and a spring. This inner outer sleeve is connected This way blocks the view inside the syringe and affects the light inspection process. In this embodiment, the protective cover unit 2 only covers the needle installation tube 12 and the syringe 11 when the syringe is not in use. Part of the distal end will not affect the light inspection process.

However, the protective cover 101 needs to achieve a fixing effect after closing. Furthermore, the protective cover unit 1 also includes an elastic plate 103. The elastic plate 103 is cantilevered in the sliding opening 102, and has a proximal end along all directions. The protective cover 101 has a radial inward tendency.

The functions and implementation methods of the elastic plate 103 are as follows:

1. When the protective cover 101 is opened, the elastic hook 202 pushes up the elastic plate 103 outward in the radial direction of the protective cover 101, so that the elastic plate 103 accumulates elastic potential energy and loosens the protective cover. At 101, the elastic potential energy of the elastic plate 103 is released, driving the protective cover 101 to eject axially along the distal direction of the injection syringe 11, achieving the automatic closing effect;

2. When the protective cover 101 is closed, the proximal end surface of the elastic plate 103 pushes up the back of the hook of the elastic hook 202. In this way, when the protective cover 101 moves toward the proximal end, it is The back of the curved hook of the elastic hook 202 resists. When moving toward the far end, the elastic hook 202 hooks the inner side of the sliding opening 102 to achieve a locking effect.

In order to make the elastic plate 103 lock the elastic hook 202 more firmly, further, the proximal end of the elastic plate 103 has a proximal stop surface 103a, which is used to push up the elastic hook when the protective cover 101 is closed. 202, thereby locking the protective cover 101.

When the protective cover 101 is opened, the nurse still needs to pull it by hand, which is very inconvenient during the injection process. Furthermore, a distal stop surface 103b is provided on the inside of the elastic plate 103 for opening the protective cover 101. When the elastic hook 202 is pushed up, the protective cover 101 is locked.

When the elastic hook 202 pushes up the elastic plate 103 radially outward along the protective cover 101, according to the interaction principle of forces, the elastic plate 103 also pushes up the elastic plate 103 radially inward along the protective cover 101. The elastic hook 202 causes the elastic hook 202 to shrink. When it crosses the distal stop surface 103b, the elastic hook 202 rebounds back to its original shape, thus hooking the distal stop surface 103b, so that the The protective cover 101 cannot slide in the distal direction even under the push of the elastic plate 103 .

In addition, when the elastic hook 202 hooks the distal stop surface 103b, it will make a "pop" sound to remind the nurse that the protective cover 101 has been locked and injection can be performed.

In order to cooperate with the proximal stop surface 103a, further, the elastic hook 202 includes a radial plate 202a. The distal side of the radial plate 202a is provided with a closing stop surface 202c for lifting the proximal stop surface 103a. End stop plane 103a.

When the closing stop surface 202c pushes up the proximal stop surface 103a, a "pop" sound will also be made to remind the nurse that the protective cover 101 has been locked and can be discarded.

At the same time, in order to cooperate with the distal stop surface 103b, further, the elastic hook 202 also includes an axial plate 202b. The proximal side of the axial plate 202b is provided with an opening stop surface 202d for jacking up. The distal stop surface 103b.

After the injection is completed, the protective cover 101 needs to be closed. In order to make the closing process smoother, further, the proximal end of the axial plate 202b expands radially outward along the protective cover 101 to push up the distal stop. When facing 103b, by pressing the elastic plate 103 radially inward or pulling the elastic plate 103 outward along the protective cover 101, the opening stop surface 202d of the axial plate 202b is aligned with the distal stop surface 103b. Get out of the jacked state.

When the elastic plate 103 is pulled radially outward, the distal stop surface 103b moves radially outward, and is separated from the opening stop surface 202d of the axial plate 202b.

The principle of pressing the elastic plate 103 radially inward to release the opening stop surface 202d of the axial plate 202b and the distal stop surface 103b from the jacked-up state is as follows:

When the elastic plate 103 expands under force, the proximal end expands to a greater extent than the distal end. The inner surface of the elastic plate 103 tilts outward from the distal end to the proximal end. The inclination mode of the axial plate 202b is consistent with the above. The inner side of the elastic plate 103 is inclined in a consistent manner, so that when the elastic plate 103 is pressed radially inward along the protective cover 101, because the length of the elastic plate 103 is longer, the length of the axial plate 202b is longer. Short, when squeezed for the same distance, the axial plate 202b shrinks more obviously. Therefore, when squeezed to a certain extent, the opening stop surface 202d of the axial plate 202b and the distal stop surface 103b disengaged, and the protective cover 101 is closed under the pushing action of the elastic plate 103 .

The advantage of this design is that after the nurse completes the injection, she only needs to use her thumb and index finger to gently pinch to close the protective cover 101. Compared with the push-to-close method, the pinch-to-close method can close the protective cover 101. There is no need for the nurse to exert force on the palm of the hand, and there is no need to move the thumb and index finger away from the palm. For nurses with shorter fingers, it can also be operated with one hand, which is an ingenious design. At the same time, pinching inward is more convenient than turning outward. There is no need to find an angle, there is no need to insert nails into the sliding opening 102, and the operation does not even need to be observed by a nurse with naked eyes.

In order to prevent the need to lift the elastic plate 103 when the protective cover 101 is opened, further, a protruding block 103c is provided on the inner surface of the proximal side of the elastic plate 103, and the needle protective sleeve 14 is sleeved on When the needle mounting member 12 is on, the protruding block 103c is pushed radially outward along the protective cover 101, so that the proximal stop surface 103a on the elastic plate 103 is in contact with the proximal stop surface 103a on the radial plate 202a. The closing stop surface 202c releases the jacking state.

In order to prevent the protruding block 103c from affecting the opening process of the protective cover 101, further, the proximal end side of the protruding block 103c has an opening guide surface 103d for when the protective cover 101 slides toward the proximal end. Push up the axial plate 202b of the elastic hook 202, so that the elastic hook 202 passes over the protruding block 103c.

In order to prevent the protruding block 103c from affecting the closing process of the protective cover 101, further, the protruding block 103c also includes a closing guide surface 103e, which is used to lift the protective cover 101 when it slides toward the distal end. The axial plate 202b of the elastic hook 202 allows the elastic hook 202 to cross the protruding block 103c.

When the protective cover 101 is sleeved and installed on the needle mounting member 12, it is simultaneously sleeved on the elastic hook 202 through deformation. However, the protective cover 101 has a certain thickness and is difficult to deform, making installation difficult. Further, , the protective cover unit 1 further includes an expansion slot 104 provided at the proximal end of the protective cover 101 for expansion of the proximal end of the protective cover 101 .

After the expansion groove 104 is provided, when the protective cover 101 is deformed, the expansion groove 104 can be expanded to provide the protective cover 101 with space for movement, so that it can more easily cross the elastic hook. 202.

In order to make the process of the protective cover 101 passing over the elastic hook 202 smoother, further, the protective cover unit 1 also includes a guide slope 105 provided at the proximal end of the protective cover 101 for pushing up the elastic hook 202 . Hook 202's axial plate 202b.

The inclination angle of the guide slope 105 is similar to that of the axial plate 202b. When the axial plate 202b is lifted up, the proximal end of the protective cover 101 is expanded, thereby crossing the elastic hook 202.

The push rod is arranged on the piston;

The piston is installed in the injection syringe 11 and used to push the medical liquid through the injection needle 13 when the push rod is pushed in the distal direction.

In this embodiment, the key point is that the push rod and the piston are detachably connected together, so that the piston can be easily installed in the injection syringe 11 in a mechanical and automated manner. The piston assembly method and the drug potting method are as follows:

S1. Place the syringe: Grasp the syringe body and make the injection syringe 11 vertical and horizontal, with the proximal opening facing upward;

In this embodiment, the "grabbing" step generally uses a programmed mechanical arm. The core of the program design is to keep the injection syringe 11 in a vertical state when it reaches the position to be potted, so that The liquid level after filling the medicine is perpendicular to the axial direction of the injection syringe 11 so that no air or less air remains after packaging but does not affect the injection process.

S2. Filling drugs: filling designated drugs into the injection syringe 11;

In this embodiment, the "designated drug" refers to a drug that is filled by itself according to customer needs. For example, if a manufacturer fills the new coronavirus vaccine, the designated drug is an inactivated new coronavirus.

S3. Sleeve plugging: insert the sleeve with the piston into the injection syringe 11, leaving a gap between the outer ring surface of the sleeve and the inner ring surface of the injection syringe 11, and then use the sleeve The barrel push rod pushes the piston into the injection syringe 11 along the inner annular surface of the sleeve;

In this embodiment, the piston is a device commonly used in syringes for pushing medicine. The piston is generally made of medical rubber. It is in a compressed state in the sleeve and will expand to fit after leaving the sleeve. The inner surface of the injection syringe 11.

In addition, the sleeve is an elongated steel tube, and the injection syringe 11 is inserted from the crimp, and then the piston is sent to a designated position using a sleeve push rod installed in the sleeve. , the designated position means that after the piston leaves the sleeve, it can be just above the liquid level of the medicinal liquid, with no air or less air left in between but does not affect the injection process.

S4. Install the push rod: Insert the push rod into the injection syringe 11 and install it on the piston to complete the potting process.

In this embodiment, a mounting slot is left at the proximal end of the piston for mounting the push rod, and a mechanical arm is used to rotate the push rod and insert it into the mounting slot.

S5. Carry out light inspection on the filled syringes, label them, and finally complete the packaging.

The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those of ordinary skill in the technical field, other modifications can be made without departing from the spirit of the present invention. Make various modifications. These modifications are non-creative and are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims

A needle-protected pre-filled syringe, including an injection syringe barrel (11), a needle mounting piece (12), an injection needle (13) and a needle protective cover (14); wherein:

The needle mounting part (12) is provided at the distal end of the injection syringe (11). The needle mounting part (12) has a through hole (12a) that communicates with the inside of the injection syringe (11). The injection needle (13) is installed on the needle mounting part (12) by inserting into the through hole (12a), and the needle protective cover (14) is sleeved on the needle mounting part (12) and completely Covering the injection needle (13), the injection syringe barrel (11), the needle mounting member (12), the injection needle (13) and the needle protective sleeve (14) have a common axis;

It is characterized in that it also includes a protective cover unit (1), and the protective cover unit (1) includes:

A protective cover (101) of the sliding port (102) is provided on it to block the injection needle (13);

It also includes an elastic hook unit (2), which includes an elastic hook (202) extending into the sliding opening (102).
A needle-protected pre-filled syringe according to claim 1, characterized in that the protective cover unit (1) further includes an elastic plate (103), the elastic plate (103) cantilevered on the sliding In the mouth (102), the proximal end has a tendency to retract radially along the protective cover (101).
A needle-protected pre-filled syringe according to claim 2, characterized in that the proximal end of the elastic plate (103) has a proximal stop surface (103a) for closing the protective cover (101). When the elastic hook (202) is pushed up, the protective cover (101) is locked.
A needle-protected pre-filled syringe according to claim 3, characterized in that a distal stop surface (103b) is provided inside the elastic plate (103) for opening the protective cover (101). When the elastic hook (202) is pushed up, the protective cover (101) is locked.
A needle-protected pre-filled syringe according to claim 4, characterized in that the elastic hook (202) includes a radial plate (202a), and a closing device is provided on the distal side of the radial plate (202a). The stop surface (202c) is used to push up the proximal stop surface (103a).
A needle-protected pre-filled syringe according to claim 5, characterized in that the elastic hook (202) further includes an axial plate (202b), and the proximal side of the axial plate (202b) is provided with The opening stop surface (202d) is used to push up the distal stop surface (103b).
A needle-protected pre-filled syringe according to claim 6, characterized in that the proximal end of the axial plate (202b) expands radially outward along the protective cover (101) to push up the distal end. When the end stop surface (103b) is at the end stop position (103b), by pressing the elastic plate (103) radially inward or pulling the elastic plate (103) outward along the protective cover (101), the opening stop position of the axial plate (202b) is The surface (202d) and the distal stop surface (103b) are out of the jacking state.
A needle-protected pre-filled syringe according to claim 5, characterized in that a protruding block (103c) is provided on the inner surface of the proximal side of the elastic plate (103), and the needle protective cover (14 ) is sleeved on the needle mounting piece (12), push the protruding block (103c) radially outward along the protective cover (101), so that the proximal end of the elastic plate (103) The stop surface (103a) and the closing stop surface (202c) on the radial plate (202a) are released from the lifted state.
A needle-protected pre-filled syringe according to claim 8, characterized in that the proximal end side of the raised block (103c) has an opening guide surface (103d), and the protective cover (101) moves toward the proximal end. When sliding, the axial plate (202b) is used to push up the elastic hook (202), so that the elastic hook (202) passes over the raised block (103c).
A needle-protected pre-filled syringe according to claim 9, characterized in that the raised block (103c) also includes a closing guide surface (103e). When the protective cover (101) slides toward the distal end, , used to push up the axial plate (202b) of the elastic hook (202), so that the elastic hook (202) passes over the raised block (103c).
A needle-protected pre-filled syringe according to claim 1, characterized in that the protective cover unit (1) further includes an expansion groove (104) provided at the proximal end of the protective cover (101), For proximal expansion of the shield (101).
A needle-protected pre-filled syringe according to claim 6, characterized in that the protective cover unit (1) further includes a guide slope (105) provided at the proximal end of the protective cover (101). On the axial plate (202b) that pushes up the elastic hook (202).
An assembly including the needle-protected pre-filled syringe according to any one of claims 1 to 12, characterized in that it includes a push rod and a piston; wherein:

The push rod is arranged on the piston;

The piston is installed in the injection syringe (11) and is used to push the medicinal liquid through the injection needle (13) when the push rod is pushed in the distal direction.
A method for installing components of a needle-protected pre-filled syringe according to any one of claims 13, characterized in that it includes the following steps:

S1. Install the needle protective sleeve (14) into the protective cover (101) along the axial direction;

S2. Connect the protective cover (101) with the needle protective cover (14) to the needle mounting piece (12) in the axial direction;

S3. Push the piston into the injection syringe (11);

S4. Set the push rod on the piston.
A method of using the assembly of the needle-protected pre-filled syringe according to any one of claims 13, characterized in that it includes the following steps:

S1. Move the protective cover (101) axially along the proximal direction of the injection syringe (11) until the back side of the elastic hook (202) contacts the distal side of the sliding port (102) , thereby exposing the needle protective cover (14);

S2. Open the needle protective cover (14) and expose the injection needle (13);

S3. Carry out injection operation;

S4. After the injection operation is completed, move the protective cover (101) axially along the distal direction of the injection syringe (11) until one side of the hook of the elastic hook (202) hooks the sliding port (102) proximal side, thus completely covering the injection needle (13).