CN116747141A - A blunt needle with an adjustable degree of curvature of the blunt surface and a method of using the same - Google Patents

Abstract

The invention discloses a blunt needle capable of adjusting the bending degree of a blunt surface and a use method thereof, and relates to the technical field of medical instruments. The first aspect, a dull needle of adjustable dull and stereotyped crooked degree, including cylindric needle bar, the needle bar top is equipped with the syringe needle, and the needle bar bottom is equipped with the needle file, is equipped with the infusion way that is used for carrying the liquid medicine in the needle bar, the syringe needle seals the needle bar top, runs through on the needle bar lateral wall to be equipped with the imbibition way that is linked together with the infusion way, is equipped with the push rod that sets up with the needle bar is coaxial in the infusion way, and the push rod is used for promoting the syringe needle and makes the syringe needle produce the bellied deformation of needle file direction of keeping away from, and the push rod top is connected with the syringe needle bottom, is equipped with the drive structure who is used for promoting the push rod and removes towards the syringe needle direction on the push rod. In a second aspect, a method of using a blunt needle that adjusts the degree of curvature of the blunt surface. The invention can change the bending degree of the top end of the needle head, avoid stabbing medical staff when the blunt needle is not used, and can puncture the rubber plug of the liquid medicine bottle when the blunt needle is used for sucking liquid medicine.

Description

A blunt needle with an adjustable degree of curvature of the blunt surface and a method of using the same

Technical field

The present invention relates to the technical field of medical devices, and in particular to a blunt needle with adjustable blunt surface curvature and a method of using the same.

Background technique

Syringes are medical tools commonly used by medical staff in their daily work. The needle tips of existing syringes are mostly sharp, which can easily cause needle stick injuries to medical staff. Needle stick injuries are currently the most common and unavoidable type of injury to medical staff. Iatrogenic injury. Needlestick injuries can cause physical trauma to medical staff and may also lead to hospital-borne infections. Needle stick injuries can easily occur when holding a syringe, when using a syringe to aspirate ampoules, and when using a syringe to penetrate a rubber stopper to aspirate medication.

As shown in Figure 1, the existing injection needle includes a needle shaft 1. The top section of the needle shaft 1 is a tip-shaped needle 2 with a cross-sectional area that decreases sharply along the top direction. The bottom end of the needle shaft 1 is provided with a The injection needle cover is arranged on the needle seat 3 on the top of the syringe. There is a sealing glue 20 between the outer wall of the needle bar 1 and the needle seat 3. The needle seat 3 is provided with a retaining ring for supporting the bottom end of the needle bar 1. The inside of the needle bar 1 An infusion channel 4 for transporting medicinal liquid is provided from the top to the bottom. This structure can easily cause needle stick injuries to the human body during use.

Contents of the invention

The object of the present invention is to provide a blunt needle with an adjustable degree of curvature of the blunt surface and a method of using it, which can change the degree of curvature of the tip of the needle, avoid stabbing medical staff when the blunt needle is not used, and use the blunt needle to absorb medicinal liquid. It can pierce the rubber stopper of the medicine bottle.

In order to solve the above technical problems, the present invention adopts the following solutions:

In the first aspect, a blunt needle with an adjustable degree of curvature of the blunt surface is only used for absorbing liquid medicine and should not be used for human body injection. It includes a cylindrical needle bar with a needle at the top and a needle at the bottom of the needle bar. The needle seat and the needle shaft are provided with an infusion channel for transporting medicinal liquid. The needle seals the top of the needle shaft. The side wall of the needle shaft is provided with a suction channel connected to the infusion channel. The infusion channel is provided with a suction channel connected to the needle shaft. A push rod arranged coaxially. The push rod is used to push the needle to cause the needle to bulge in a direction away from the needle seat. The top end of the push rod is connected to the bottom end of the needle. There is a push rod on the push rod for pushing the push rod to move in the direction of the needle. Driving structure, the needle is made of elastic alloy or plastic alloy;

When a blunt needle is not used, the tip of the needle has a flat surface perpendicular to the axis of the needle shaft;

In the state of using a blunt needle, the push rod moves upward relative to the original position of the push rod itself, and the top of the needle becomes a convex shape with a flat top. The top edge of the needle is rounded, and the suction channel runs through the needle shaft to avoid connecting the outside of the needle shaft with the infusion channel. The suction channel is located adjacent to the needle, and the top of the push rod is flat. If a blunt needle is not used, use a blunt needle. The state before, that is, the state where the blunt needle is installed in front of the injection syringe, the state of using the blunt needle, that is, after the blunt needle is installed on the injection syringe, the blunt needle is about to, is being, or has pierced the rubber of the liquid medicine bottle or ampoule bottle blocked state. Its function is to adjust the position of the push rod through the setting of the needle material and the push rod, so that a height difference is formed between the top of the push rod and the top of the needle bar, causing the push rod to push the needle to deform, so that the top of the needle is flat. convex shape. Since the tip of the needle is flat when the blunt needle is not used, it is not easy to hurt the medical staff. However, when the blunt needle is used, the needle can smoothly pierce the rubber stopper of the medicinal solution bottle or ampoule bottle. The blunt needle achieves the effect of taking medicine. During the process of sucking the medicine liquid, the suction channel is immersed in the medicine liquid, and the piston rod of the injection syringe is pulled, and the medicine liquid can be sucked into the needle through the suction channel and the infusion channel in sequence. inside the cylinder.

Furthermore, when a blunt needle is used, the minimum area of the convex plane at the tip of the needle is 0.03141mm ² and the maximum area of the convex plane at the tip of the needle is 0.2827mm ² . Its function is to set the area range of the raised plane at the top of the needle so that the raised plane at the top of the needle can pierce the rubber stopper but not the human epidermis, so that it can pierce the rubber stopper and absorb the medicinal liquid without The effect of stabbing medical staff makes it possible to avoid stabbing medical staff even when using a blunt needle, which is highly safe.

Furthermore, the outer wall of the needle bar is provided with a snap-in structure for restricting the needle bar from moving toward the needle head. Its function is to fix the position of the needle bar through the setting of the snap-in structure, thereby preventing the needle bar from moving upward together when pushing the push rod to move toward the needle, so that the top of the push rod and the needle cannot move together. A height difference is formed at the top of the pole.

Further, the snap-in structure includes a snap-in groove provided on the inner wall of the needle seat and a snap-in block arranged on the outer wall of the needle bar, and the snap-in block is located in the snap-in groove. Its function is to achieve the fixing effect on the needle bar through the setting of the snap-in hole and the snap-in groove.

Further, the wall surface of the needle bar is provided with a snap-in placement slot for placing the snap-in block. The snap-in placement slot opens toward the inner wall of the needle seat. The snap-in slot is provided with a snap-in elastic piece, and the snap-in block is provided with a snap-in slot. Between the clamping elastic member and the inner wall of the needle seat. One end of the snap-in block is located in the snap-in groove, and the other end is in the snap-in placement slot. The snap-in elastic piece can be a spring piece or an elastic ball, such as a rubber ball. Its function is to, through the setting of the snap-in elastic member, during the process of inserting the needle bar into the needle seat, the inner wall of the needle seat squeezes the snap-in block into the snap-in groove. When the snap-in block moves to the height of the snap-in slot, At this time, due to the elastic effect of the clamping elastic member, the clamping block is pushed into the clamping groove, thereby completing the fixation of the needle bar.

Further, the length of the push rod is greater than the length of the needle bar. The driving structure includes a push plate provided at the bottom end of the push rod and a sealing ring provided on the inner wall of the needle seat. An infusion channel connected to the infusion channel is provided in the needle seat. ;

When a blunt needle is not used, the push plate and the sealing ring are in the same plane and the combination of the push plate and the sealing ring completely seals the infusion channel in the needle seat;

In the state of using a blunt needle, the push plate and the sealing ring are set separately. Its function is to close the infusion channel in the needle seat through the setting of the push plate and sealing ring when the blunt needle is not used, and pull out the piston rod of the injection syringe before installing the needle seat on the injection syringe. , so that air enters the injection syringe, and then install the needle seat on the injection syringe. While pressing the needle seat tightly on the injection syringe, push the piston rod toward the injection syringe to make the inside of the injection syringe The gas pushes the push plate upward, thereby connecting the infusion channel with the infusion channel and at the same time causing the center of the needle tip to protrude upward, and then the injection syringe equipped with the blunt needle can be used to suck the medicinal liquid.

Further, the inner wall of the needle bar is provided with an embedded groove, and the outer wall of the push rod is provided with a positioning protrusion;

When a blunt needle is not used, the positioning protrusion is provided in the embedding groove on the side away from the needle head in the axial direction of the needle bar;

In the state of using a blunt needle, the end of the positioning protrusion away from the axis of the push rod is located at the deepest point of the embedding groove. The positioning protrusion is a movable block. Its function is that through the setting of the embedding groove and the positioning protrusion, when a blunt needle is used, the positioning protrusion can be stuck in the embedding groove, thus preventing the needle from pushing the push rod back into the needle bar when the needle is used to pierce the rubber stopper. It shrinks, so it can maintain the shape of the needle during the process of piercing the rubber stopper, so that the needle can pierce the rubber stopper smoothly.

Furthermore, the push rod is provided with a positioning groove for placing the positioning protrusion. The positioning groove opens toward the inner wall of the needle bar. The positioning groove is provided with a positioning elastic piece. The positioning protrusion is arranged between the positioning elastic piece and the needle. between the inner walls of the rod. One end of the positioning protrusion is always located in the positioning groove. When using a blunt needle, the other end of the positioning protrusion is located in the embedding groove. The positioning elastic member can use a spring leaf or an elastic ball, such as a rubber ball. Its function is to push the positioning protrusion into the embedding groove when the push plate pushes the push rod to move toward the needle through the setting of the positioning elastic member, thus blocking the push rod. When the push rod receives the rubber stopper, it is transferred to the needle. When there is a reaction force, it plays a supporting role on the push rod.

Furthermore, when a blunt needle is not used, the distance between the end of the positioning protrusion away from the axis of the push rod and the deepest part of the embedding groove in the axial direction of the needle rod is greater than the thickness of the sealing ring. The deepest part of the embedding groove is the farthest distance between the embedding groove and the axial direction of the needle bar in the radial direction of the needle bar. Its function is to design the distance between the end of the positioning protrusion away from the axis of the push rod and the deepest part of the embedding groove and the thickness of the sealing ring, so that when the end of the positioning protrusion away from the axis of the push rod is located at the deepest part of the embedding groove. When upward, the push plate and sealing ring are completely separated.

In the second aspect, a method of using a blunt needle with an adjustable degree of curvature of a blunt surface, using the above-mentioned blunt needle with an adjustable degree of curvature of a blunt surface, includes the following steps:

Step S1, install the needle seat on the injection syringe;

Step S2: Control the driving structure to push the push rod to move toward the needle;

Step S3: Prick the seal of the medicinal solution bottle with a convex needle with a flat top, and suck the medicinal solution.

The invention has the beneficial effects:

1. Through the setting of the needle material and the push rod, the position of the push rod can be raised, so that a height difference is formed between the top of the push rod and the top of the needle bar, causing the push rod to push the needle to deform, so that the top of the needle forms a convex top with a flat top. Since the tip of the needle is flat when the blunt needle is not used, it is not easy to hurt the medical staff. However, when the blunt needle is used, the needle can smoothly pierce the rubber stopper of the medicinal solution bottle or ampoule bottle, making the blunt needle To achieve the effect of taking medicine, during the process of sucking the medicine liquid, immerse the suction channel into the medicine liquid, pull the piston rod of the injection syringe, and the medicine liquid can be sucked into the syringe through the suction channel and infusion channel in sequence. ;

2. Through the setting of the push plate and sealing ring, without using a blunt needle, seal the infusion channel in the needle seat. Before installing the needle seat on the injection syringe, pull out the piston rod of the injection syringe so that The air enters the injection syringe, and then the needle seat is installed on the injection syringe. While pressing the needle seat tightly on the injection syringe, push the piston rod toward the injection syringe to release the gas in the injection syringe. Push the push plate upward to connect the infusion channel with the infusion channel and at the same time make the center of the top of the needle protrude upward. Then the injection syringe equipped with the blunt needle can be used to suck the medicinal liquid.

Description of the drawings

Figure 1 is a schematic three-dimensional structural diagram of an injection needle in the prior art;

Figure 2 is a schematic three-dimensional structural diagram of the blunt needle in an unused state in Embodiment 1;

Figure 3 is a schematic top view of the blunt needle in an unused state in Embodiment 1;

Figure 4 is a schematic cross-sectional structural diagram at A-A in Figure 3;

Figure 5 is an enlarged structural schematic diagram of C in Figure 4;

Figure 6 is a schematic cross-sectional structural diagram at B-B in Figure 3;

Figure 7 is an enlarged structural diagram of D in Figure 6;

Figure 8 is a schematic cross-sectional structural diagram of the blunt needle at B-B when in use;

Figure 9 is an enlarged structural schematic diagram of E in Figure 8.

Reference signs: 1. Needle bar; 2. Needle; 3. Needle seat; 4. Infusion channel; 5. Suction channel; 6. Push rod; 7. Driving structure; 8. Snap-in structure; 9. Snap-in groove ; 10. Snap block; 11. Snap placement slot; 12. Snap elastic piece; 13. Push plate; 14. Sealing ring; 15. Infusion channel; 16. Embedding slot; 17. Positioning protrusion; 18. Positioning Placement slot; 19. Positioning elastic piece; 20. Sealing glue.

Detailed ways

The present invention will be further described in detail below with reference to the examples and drawings, but the implementation of the present invention is not limited thereto.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "longitudinal", "lateral", and "horizontal" The orientation or positional relationships indicated by "inside", "outside", "front", "back", "top", "bottom", etc. are based on the orientation or positional relationship shown in the accompanying drawings, or when the inventive product is used. The conventionally placed orientations or positional relationships are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. Limitations of Invention.

In the description of the present invention, it should also be noted that, unless otherwise explicitly stated and limited, the terms "set", "open", "installed", "connected" and "connected" should be understood in a broad sense, for example, It can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, or it can be an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be an internal connection between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood on a case-by-case basis.

Example 1

In the first aspect, a blunt needle with an adjustable degree of blunt surface curvature, as shown in Figures 2 and 3, includes a hollow cylindrical needle bar 1 with a needle 2 at the top and a needle 2 at the bottom of the needle bar 1. There is a needle seat 3, and an infusion channel 4 for transporting medicinal liquid is provided in the needle bar 1. The needle 2 closes the top of the needle bar 1, and a suction channel 5 connected to the infusion channel 4 is provided on the side wall of the needle bar 1. , there is a cylindrical push rod 6 arranged coaxially with the needle bar 1 in the infusion channel 4. As shown in Figure 4, the top end of the push rod 6 is connected to the bottom end of the needle 2, and there is a push rod 6 on the push rod 6 for pushing the push rod. 6. The driving structure 7 moves in the direction of the needle 2. The needle 2 is made of plastic alloy. The plastic alloy can have a certain hardness and can produce a certain deformation and is not easy to rebound;

As shown in Figure 6, when a blunt needle is not used, the top end of the needle 2 is in a plane shape perpendicular to the axis of the needle bar 1;

As shown in Figure 8, when a blunt needle is used, the push rod 6 moves upward relative to its original position, and the top of the needle 2 takes on a convex shape with a flat top. The top edge of needle 2 is rounded, and the suction channel 5 runs through the needle shaft 1 to avoid connecting the outside of the needle shaft 1 with the infusion channel 4. The suction channel 5 is located adjacent to the needle 2, and the top of the push rod 6 is flat and is not used. The state of the blunt needle is the state before using the blunt needle, that is, the state where the blunt needle is installed in front of the injection syringe. The state of using the blunt needle is that after the blunt needle is installed on the injection syringe, the blunt needle is about to, is being, or has been pierced. The condition of the rubber stopper of the medicinal solution bottle or ampoule. Its function is that by setting the material of the needle 2 and the push rod 6, the position of the push rod 6 can be raised, so that a height difference is formed between the top of the push rod 6 and the top of the needle bar 1, so that the push rod 6 pushes the needle 2 to deform, thereby The top of the needle 2 is formed into a convex shape with a flat top. Since the top of the needle 2 is flat when the blunt needle is not used, it is not easy to puncture the medical staff, and when the blunt needle is used, the needle 2 can smoothly penetrate the medicine. The rubber stopper of the liquid bottle or ampoule allows the blunt needle to achieve the effect of taking medicine. During the process of absorbing the medicine liquid, immerse the suction channel 5 into the medicine liquid, pull the piston rod of the injection syringe, and the medicine liquid can be ejected. The liquid is inhaled into the syringe through the suction channel 5 and the infusion channel 4 in sequence. The injection syringe and piston rod are common existing technologies, so they will not be described again.

Specifically, when a blunt needle is used, the minimum area of the convex plane at the top of the needle 2 is 0.03141mm ² , and the maximum area of the convex plane at the top of the needle 2 is 0.2827mm ² . Its function is to set the area range of the convex plane at the top of the needle 2 so that the convex plane at the top of the needle 2 can pierce the rubber stopper but not the human epidermis, so that it can pierce the rubber stopper to absorb the medicinal liquid and also The effect of not stabbing medical staff makes it possible to avoid stabbing medical staff even when using a blunt needle, which is highly safe.

The experimental process to derive the range of this cross-sectional area is as follows:

1. Calculation of the minimum cross-section where the blunt surface cannot penetrate the skin when vertical pressure is applied:

1.1. Pressure required to break the skin: According to the theory of Henry S et al. in the article Microfabricated microneedles: a novel approach to transdermal drug delivery, the insertion pressure for skin puncture is 3.183MPa.

1.2. Estimation of accidental poke force during vertical pressure: Randomly select 10 medical staff, simulate the normal action of pumping medicine, and test the force of accidental poke. Each person is tested 3 times. The average value is: 0.1N.

1.3. The minimum cross-section that does not puncture the skin when vertical pressure is applied: S=F/P. From this, the minimum cross-sectional area of the blunt surface under stress is S=0.03141mm ² , and the minimum radius R=0.1mm (if the cross-section is circular ).

2. The minimum cross-section that the blunt surface cannot penetrate the skin when vertical pressure is applied when sliding horizontally:

From New Zealand white rabbits, complete abdominal tissue with muscles covering an area of approximately 4 × 4 cm was removed after anesthesia. The muscle tissue is bluntly separated to expose the dermal layer of the skin to simulate normal human epidermis. 10 medical staff were selected, holding blunt needles 2 with different cross-sections, to simulate normal clinical operations and draw across the dermis of the experimental rabbit. When a blunt needle with a force-bearing surface radius of 0.0012mm is used, the skin can be scratched. Gradually increase the radius of the blunt surface. When using a blunt needle with a radius of 0.003 mm, the skin will not be scratched. Therefore, the minimum radius when sliding horizontally is 0.003mm.

3. Calculation of the maximum cross-section that a blunt surface under force can penetrate the rubber stopper:

3.1. Experimental design: According to the first method of measuring the puncture force of rubber stoppers and gaskets for injections (YBB00322004-2015), blunt needles with different cross-sections are used for puncture, starting from the blunt needle with a radius of R=0.1mm. Each time R increases by 0.025mm, measure the force used to pierce the rubber stopper.

3.2. Strength limit: According to regulations, the average puncture force shall not exceed 75N.

3.3. Maximum cross section: When R=0.3mm, the puncture force is 73N. When R=0.325mm, the puncture force exceeds 75N. Therefore, the maximum cross-section of the blunt force-bearing surface is selected to be 0.2827mm ² , R=0.3mm (assuming the cross-section is circular).

Specifically, as shown in FIG. 4 , the outer wall of the needle bar 1 is provided with a snap-in structure 8 for restricting the movement of the needle bar 1 toward the needle head 2 . The snap-in structure 8 is symmetrically arranged on the left and right sides of the axis of the needle bar 1 . Its function is to fix the position of the needle bar 1 through the setting of the snap-in structure 8, thereby preventing the needle bar 1 from being driven upward when the push rod 6 is moved toward the needle 2, thereby preventing the needle bar 1 from moving upward. The top end of push rod 6 and the top end of needle bar 1 form a height difference.

Specifically, as shown in Figure 5, the snap-in structure 8 includes a snap-in groove 9 provided on the inner wall of the needle seat 3 and a snap-in block 10 provided on the outer wall of the needle bar 1. The snap-in block 10 is located in the snap-in slot. Within 9. Its function is to achieve the fixing effect on the needle bar 1 through the arrangement of the snap-in hole and the snap-in groove 9 .

Specifically, as shown in Figure 5, the wall surface of the needle bar 1 is provided with a snap-in placement slot 11 for placing the snap-in block 10. The snap-in placement slot 11 opens toward the inner wall of the needle seat 3, and the snap-in slot 9 is placed in the slot. There is a snap-in elastic member 12 inside, and the snap-in block 10 is disposed between the snap-in elastic member 12 and the inner wall of the needle seat 3 . One end of the clamping block 10 is located in the clamping slot 9, and the other end is located in the clamping placement slot 11. The clamping elastic piece is a spring piece. The snap-in block 10 , the snap-in slot 9 and the snap-in placement slot 11 are all in the shape of a rectangular parallelepiped with the same cross-section along the radial direction of the needle bar 1 . Its function is that through the arrangement of the snap-in elastic member 12, when the needle bar 1 is inserted into the needle seat 3, the inner wall of the needle seat 3 squeezes the snap-in block 10 into the snap-in groove 9. When the snap-in block 10 When moving to the height of the engaging groove 9, due to the elastic effect of the engaging elastic member 12, the engaging block 10 is pushed into the engaging groove 9, thereby completing the fixation of the needle bar 1.

Specifically, as shown in Figures 4 and 5, the length of the push rod 6 is greater than the length of the needle bar 1, and the driving structure 7 includes a push plate 13 provided at the bottom end of the push rod 6 and a seal provided on the inner wall of the needle seat 3 Ring 14, the needle seat 3 is provided with an infusion channel 15 connected with the infusion channel 4, the push plate 13 is disc-shaped, the sealing ring 14 is annular, the thickness of the push plate 13 and the sealing ring 14 (i.e. on its own axis The outer wall of the sealing ring 14 is fixedly connected to the inner wall of the needle seat 3. The inner wall of the sealing ring 14 is in the shape of a concave arc surface. The sealing ring 14 is made of elastic material that can produce slight deformation. The push plate The outer wall of 13 is in the shape of an arc with the same curvature as the inner wall of the sealing ring 14. When a blunt needle is not used, the outer wall of the push plate 13 is in close contact with the inner wall of the seal ring 14. The outer wall of the push plate 13 is in contact with the seal. The design of the arc surface of the inner wall of the ring 14 can avoid the misalignment of the push plate 13 and the sealing ring 14 without using a blunt needle, improve the sealing effect of the combination of the push plate 13 and the sealing ring 14, and ensure that the injection is pushed inward. When the piston rod of the syringe is inserted, the air in the injection syringe can accumulate enough pressure to cause slight deformation of the sealing ring 14, and push the push plate 13 out of the sealing ring 14;

As shown in Figure 6, when a blunt needle is not used, the push plate 13 and the sealing ring 14 are in the same plane, and the combination of the push plate 13 and the sealing ring 14 completely seals the infusion channel 15 in the needle seat 3;

As shown in FIG. 8 , in the state of using a blunt needle, the push plate 13 and the sealing ring 14 are provided separately. Its function is to seal the infusion channel 15 in the needle seat 3 through the arrangement of the push plate 13 and the sealing ring 14 when the blunt needle is not used. Before the needle seat 3 is installed on the injection syringe, the injection can be pulled out. The piston rod of the syringe allows air to enter the injection syringe. After installing the needle seat 3 on the injection syringe, push the piston rod toward the injection syringe while pressing the needle seat 3 tightly on the injection syringe. Move so that the gas in the injection syringe pushes up the push plate 13, thereby connecting the infusion channel 15 with the infusion channel 4 and at the same time causing the top center of the needle 2 to protrude upward, and then the injection syringe equipped with this blunt needle can be used. Carry out the operation of absorbing liquid medicine.

Specifically, as shown in Figure 7, the inner wall of the needle bar 1 is provided with an embedding groove 16, and the outer wall of the push rod 6 is provided with a positioning protrusion 17;

As shown in Figure 7, when a blunt needle is not used, the positioning protrusion 17 is provided in the embedding groove 16 on the side away from the needle head 2 in the axial direction of the needle bar 1;

As shown in FIG. 9 , in the state of using a blunt needle, the end of the positioning protrusion 17 away from the axis of the push rod 6 is located at the deepest part of the embedding groove 16 . The positioning protrusion 17 is a movable block. Its function is that through the arrangement of the embedding groove 16 and the positioning protrusion 17, when a blunt needle is used, the positioning protrusion can be stuck in the embedding groove 16, thereby preventing the needle 2 from pushing the push rod when the needle 2 is used to pierce the rubber stopper. 6 retracts into the needle shaft 1, so that the shape of the needle 2 during the process of piercing the rubber stopper can be maintained, so that the needle 2 can pierce the rubber stopper smoothly.

Specifically, as shown in Figure 7, the push rod 6 is provided with a positioning groove 18 for placing the positioning protrusion 17. The positioning groove 18 opens toward the inner wall of the needle bar 1, and the positioning groove 18 is provided with a positioning elasticity. Part 19, the positioning protrusion 17 is provided between the positioning elastic part 19 and the inner wall of the needle bar 1. One end of the positioning protrusion 17 is always located in the positioning groove 18 . When using a blunt needle, the other end of the positioning protrusion 17 is located in the embedding groove 16 . The positioning elastic member 19 adopts a spring leaf. The positioning groove 18 is in the shape of a rectangular parallelepiped, and the positioning protrusion 17 is in the shape of a wedge-shaped block. Specifically, the positioning protrusion 17 is in the form of a right-angled trapezoidal cylinder with a sloping plate facing the inner wall of the needle bar 1, and the positioning protrusion 17 is away from the needle 2. The end surface area in the direction is larger than the end surface area of the positioning protrusion 17 facing the needle 2. The shape and size of the embedding groove 16 is the same as the end of the positioning protrusion 17 facing the inner wall of the needle bar 1. The positioning protrusion when a blunt needle is not used Between the position on the inner wall of the needle bar 1 corresponding to 17 and the embedding groove 16, there is an arc-shaped gentle rising slope that slowly approaches the axis of the needle bar 1 from the needle seat 3 to the needle head 2. Its function is that, through the arrangement of the positioning elastic member 19, when the push plate 13 pushes the push rod 6 to move in the direction of the needle 2, the positioning protrusion 17 can be pushed into the embedding groove 16, thereby blocking the push rod 6. When the rod 6 receives the reaction force transmitted from the rubber stopper to the needle 2, it supports the push rod 6.

Specifically, when a blunt needle is not used, the distance between the end of the positioning protrusion 17 away from the axis of the push rod 6 and the deepest part of the embedding groove 16 in the axial direction of the needle rod 1 is greater than the thickness of the sealing ring 14 . The deepest part of the embedding groove 16 is the farthest distance between the embedding groove 16 and the axial direction of the needle bar 1 in the radial direction of the needle bar 1 . Its function is to design the distance between the end of the positioning protrusion 17 away from the axis of the push rod 6 and the deepest part of the embedded groove 16 and the thickness of the sealing ring 14 so that when the end of the positioning protrusion 17 is far away from the axis of the push rod 6 When located at the deepest point of the embedding groove 16 , the push plate 13 is completely separated from the sealing ring 14 .

Specifically, as shown in Figure 2, a sealing glue 20 is provided between the outer wall of the needle bar 1 and the top of the needle seat 3, and a blocking ring for supporting the bottom end of the needle bar 1 is provided in the needle seat 3.

In the second aspect, a method of using a blunt needle with an adjustable degree of curvature of a blunt surface, using the above-mentioned blunt needle with an adjustable degree of curvature of a blunt surface, includes the following steps:

Step S1, install the needle seat 3 on the injection syringe;

Step S2, control the driving structure 7 to push the push rod 6 to move in the direction of the needle 2;

Step S3: Prick the seal of the medicinal solution bottle with the convex needle 2 with a flat top, and suck the medicinal solution.

The working principle of this embodiment is explained as follows: first, pull out the piston rod of the injection syringe to allow air to enter the injection syringe, then install the needle seat 3 on the injection syringe, and press the needle seat 3 tightly on the injection syringe. while pushing the piston rod to move toward the needle barrel, the air pressure between the piston rod and the push plate 13 gradually increases, and finally the push plate 13 is pushed open, so that the push plate 13 drives the push rod 6 to move toward the needle 2. Since the needle rod 1 Fixed by the clamping structure 8, the needle 2 is pushed upward by the top of the push rod 6. There is a height difference between the top of the push rod 6 and the top of the needle bar 1. The top of the needle 2 has a convex shape with a flat top, and at the same time, the positioning protrusion 17 passes Slowly ascending the slope, it is gradually pushed into the positioning groove 18 until the positioning protrusion 17 reaches the height of the embedding groove 16. Under the push of the positioning elastic member 19, the positioning protrusion 17 snaps into the embedding groove 16, completing the push rod. 6 height fixed.

The above are only preferred embodiments of the present invention and do not limit the present invention in any form. According to the technical essence of the present invention and within the spirit and principles of the present invention, any simple modifications to the above embodiments may be made. Modifications, equivalent substitutions and improvements, etc., all still fall within the protection scope of the technical solution of the present invention.

Claims (10)

1. The utility model provides an obtuse needle of adjustable blunt face crooked degree, includes cylinder form needle bar (1), and needle bar (1) top is equipped with syringe needle (2), and needle bar (1) bottom is equipped with needle file (3), is equipped with infusion way (4) that are used for carrying the liquid medicine in needle bar (1), its characterized in that: the needle head (2) seals the top end of the needle rod (1), a liquid suction channel (5) communicated with the infusion channel (4) is penetrated through the side wall of the needle rod (1), a push rod (6) coaxially arranged with the needle rod (1) is arranged in the infusion channel (4), the top end of the push rod (6) is connected with the bottom end of the needle head (2), and a driving structure (7) for pushing the push rod (6) to move towards the needle head (2) is arranged on the push rod (6);

in the state of not using the blunt needle, the top end of the needle head (2) is in a plane shape which is perpendicular to the axis of the needle rod (1);

in the state of using the blunt needle, the push rod (6) moves upwards relative to the original position of the push rod (6), and the top end of the needle head (2) is in a convex shape with the top end being a plane.

2. An adjustable according to claim 1Dull needle of dull face bending degree, its characterized in that: in the state of using the blunt needle, the minimum area of the plane of the protruding top end of the needle head (2) is 0.03141mm ² The maximum area of the plane of the protrusion at the top end of the needle head (2) is 0.2827mm ² 。

3. The blunt needle of claim 1, wherein the blunt surface is adjustable for degree of curvature, wherein: the outer wall of the needle bar (1) is provided with a clamping structure (8) for limiting the needle bar (1) to move towards the needle head (2).

4. A blunt needle with adjustable degree of curvature of blunt surface as claimed in claim 3, wherein: the clamping structure (8) comprises a clamping groove (9) arranged on the inner wall of the needle seat (3) and a clamping block (10) arranged on the outer wall of the needle rod (1), wherein the clamping block (10) is positioned in the clamping groove (9).

5. The blunt needle of claim 4, wherein the blunt surface is curved to an adjustable degree: the needle bar is characterized in that a clamping placing groove (11) for placing a clamping block (10) is formed in the wall surface of the needle bar (1), the clamping placing groove (11) is opened towards the inner wall direction of the needle seat (3), a clamping elastic piece (12) is arranged in the placing groove of the clamping groove (9), and the clamping block (10) is arranged between the clamping elastic piece (12) and the inner wall of the needle seat (3).

6. The blunt needle of claim 1, wherein the blunt surface is adjustable for degree of curvature, wherein: the length of the push rod (6) is greater than that of the needle rod (1), the driving structure (7) comprises a push plate (13) arranged at the bottom end of the push rod (6) and a sealing ring (14) arranged on the inner wall of the needle seat (3), and an infusion channel (15) communicated with the infusion channel (4) is arranged in the needle seat (3);

in the state of not using the blunt needle, the push plate (13) and the sealing ring (14) are positioned in the same plane, and the whole body after the push plate (13) and the sealing ring (14) are combined seals the transfusion channel (15) in the needle seat (3);

in the state of using the blunt needle, the push plate (13) is separated from the sealing ring (14).

7. The blunt needle of claim 6, wherein the blunt surface is curved to an adjustable degree: an embedded groove (16) is formed in the inner wall of the needle bar (1), and a positioning protrusion (17) is formed in the outer wall of the push rod (6);

in the state of not using the blunt needle, the positioning bulge (17) is arranged on one side of the embedded groove (16) far away from the needle head (2) in the axial direction of the needle rod (1);

in the state of using the blunt needle, the end of the positioning protrusion (17) away from the axis of the push rod (6) is positioned at the deepest part of the embedded groove (16).

8. The blunt needle of claim 7, wherein the blunt surface is curved to an adjustable degree: the push rod (6) is internally provided with a positioning placing groove (18) for placing a positioning bulge (17), the positioning placing groove (18) is opened towards the inner wall direction of the needle rod (1), the positioning placing groove (18) is internally provided with a positioning elastic piece (19), and the positioning bulge (17) is arranged between the positioning elastic piece (19) and the inner wall of the needle rod (1).

9. The blunt needle of claim 7, wherein the blunt surface is curved to an adjustable degree: in the state of not using the blunt needle, the distance between the end of the positioning protrusion (17) far away from the axis of the push rod (6) and the deepest embedded groove (16) in the axial direction of the needle rod (1) is larger than the thickness of the sealing ring (14).

10. A method of using a blunt needle with adjustable degree of curvature of the blunt surface, comprising: a blunt needle for use in any of claims 1-9 with an adjustable degree of curvature of the blunt surface, comprising the steps of:

s1, mounting a needle seat (3) on an injection syringe;

s2, controlling a driving structure (7) to push a push rod (6) to move towards the needle head (2);

and S3, puncturing the seal of the liquid medicine bottle by a needle head (2) with a plane top end in a protruding shape, and sucking the liquid medicine.