CN214105485U - Low-resistance syringe rubber plug - Google Patents

Abstract

The utility model discloses a low-resistance syringe rubber plug, which is a silica gel plug and comprises a cavity for accommodating a core bar at the end part of a push rod, wherein the top end of the rubber plug is provided with an arched back which is arched upwards, an integrally formed upper sealing sheet is arranged on the circumference of the outer circumferential wall at the top end of the rubber plug, and the upper sealing sheet inclines outwards along the axial direction of the rubber plug; an upper annular groove is formed between the bottom edge of the arch back and the inner side surface of the upper sealing sheet; and the bottom end of the rubber plug is provided with a lower sealing sheet which is symmetrical to the upper sealing sheet. The utility model discloses a low resistance syringe plug has simple structure, can reduce the resistance of plug and a section of thick bamboo inner wall along with the degree of tightness between barrel internal pressure change automatically regulated plug and the barrel inner wall, still can keep sealed with the barrel inner wall simultaneously, avoids the advantage of weeping, sepage.

Description

Low-resistance syringe rubber plug

Technical Field

The utility model relates to the technical field of medical appliances, in particular to a low-resistance syringe rubber plug.

Background

The injector is an indispensable appliance in medical treatment, in order to prevent the leakage around the rubber plug of the injection and obtain a good leak-proof sealing effect, the piston must be pressed against the inner wall of the cylinder, if the interference between the cylinder and the rubber plug is too large, the sliding performance is affected, the rubber plug is difficult to freely move in the cylinder, an operator needs to use a larger initial driving force to move the rubber plug, and the injection liquid volume rate of the injector is uneven; particularly, in the case of anesthetic injection, the initial injection amount of the anesthetic is large due to the initial large driving force, so that a patient is likely to have severe allergic reaction due to sudden reception of a large amount of the anesthetic, thereby further causing medical accidents such as sudden arrhythmia or heart failure, and leakage occurs if the interference amount is small. Therefore, how to reduce the friction resistance between the inner wall of the syringe barrel and the rubber plug sliding in the syringe barrel becomes a difficult problem in the design of the current syringe.

Disclosure of Invention

An object of the utility model is to overcome the defect that exists among the prior art, provide a simple structure, can reduce the resistance of plug and a section of thick bamboo inner wall along with the degree of tightness between barrel internal pressure change automatically regulated plug and the barrel inner wall, still can keep sealed with the barrel inner wall simultaneously, avoid the low resistance syringe plug of weeping, sepage.

In order to achieve the purpose, the technical scheme of the utility model is to design a low-resistance syringe rubber plug which is a silica gel plug and comprises a cavity for accommodating a core bar at the end part of a push rod, wherein the top end of the rubber plug is provided with an arched back which is arched upwards, an integrally formed upper sealing sheet is arranged on the upper circumference of the outer circumferential wall at the top end of the rubber plug, and the upper sealing sheet inclines outwards along the axial direction of the rubber plug; an upper annular groove is formed between the bottom edge of the arch back and the inner side surface of the upper sealing sheet; and the bottom end of the rubber plug is provided with a lower sealing sheet which is symmetrical to the upper sealing sheet. When the rubber plug is in a static state, the rubber plug is in contact with the inner wall of the needle cylinder through the edge of the upper sealing piece and the edge of the lower sealing piece respectively, and the contact surface is the smallest. When liquid is pumped, the push rod is pulled backwards, the bottom surface of the rubber plug is extruded by external air pressure to move towards the core rod under the action of negative pressure in the cylinder, meanwhile, the inner wall of the bottom surface of the rubber plug is extruded by pulling force exerted on the core rod positioned in the cavity, so that the edge of the lower sealing sheet below the rubber plug is extruded towards the inner wall of the cylinder and slightly overturned, the contact surface of the edge of the lower sealing sheet and the inner wall of the cylinder is increased, the sealing property of the rubber plug and the inner wall of the cylinder is increased, and liquid medicine is sucked into the cylinder along with the action force of the negative pressure; along with the liquid medicine gets into in the cylinder, the negative pressure value reduces gradually, and the plug kick-backs, and the lower gasket kick-backs, has reduced the area of contact with cylinder inner wall spare again to the frictional resistance with cylinder inner wall spare has been reduced. When the push rod is pushed forward during injection, under the action of positive pressure in the cylinder and the action force of extruding the rubber plug from inside to outside at the top end of the core rod positioned in the cavity, the edge of the upper sealing sheet at the top end of the rubber plug is extruded towards the inner wall of the cylinder and slightly rolled, the contact surface between the edge of the upper sealing sheet and the inner wall of the cylinder is increased, and the liquid medicine is prevented from leaking between the rubber plug and the inner wall of the cylinder during pushing injection; when injecting liquid, because a section of thick bamboo malleation, the hunch back of plug also can be extruded and extrude to all around, be equipped with annular groove on the arch back between the base of hunch back and the medial surface of last gasket, the hunch back of body, the effect of mutually supporting between last annular groove and the last gasket three, make when the hunch back of body is extruded and when transmitting the extrusion force all around, the extrusion force transmits to annular groove department and is let out, the strength of gasket on the hunch back deformation extrusion has been reduced, the frictional force of last gasket and barrel inner wall has been reduced, thereby the resistance when the initial promotion resistance and the motion of plug has been reduced. The utility model discloses a plug is contradicted, the roll-over is sealed with the barrel inner wall through the edge of last gasket and lower gasket respectively, and through the hunch back, the effect of mutually supporting between annular groove and the last gasket three, has both guaranteed that plug and syringe inner wall are sealed, do not leak, reduces the frictional resistance of plug because of receiving production between extrusion and the cylinder inner wall again simultaneously, frictional resistance reduces to 0.1N to reach low resistance, the purpose of strong seal.

In order to improve the sealing performance of the rubber plug and the cylinder body during injection, the preferable technical scheme is that the height difference is formed between the top end of the core rod and the top end inside the cavity, and the outer circumference of the core rod is in clearance fit with the inner wall of the circumference of the cavity. The top end of the core rod and the top end of the cavity inner ratio have a height difference, and when the cylinder is in positive pressure, the deformation amount of the rubber plug is improved, so that the extrusion force of the rubber plug on the upper sealing sheet is improved, and the sealing property of the rubber plug and the cylinder body is further improved.

In order to further balance the effects of improving the sealing property of the rubber plug and reducing the frictional resistance of the rubber plug, a further preferred technical scheme is that the included angle between the upper sealing sheet, the lower sealing sheet and the outer circumferential surface of the rubber plug is 10-30 degrees.

In order to facilitate the turning over of the edges of the sealing pieces, the preferable technical scheme is that the inner side surfaces of the edges of the upper sealing piece and the lower sealing piece are inclined surfaces, the included angle between the inner side surface and the outer side surface is 20-30 degrees, and the minimum thickness of the edges is 0.05-0.1 mm.

The further preferable technical proposal is that the width of the bottom surface of the upper annular groove is 0.2mm-0.5mm, and the depth is 0.2mm-0.6 mm.

The technical scheme is that the outer circumferential wall of the rubber plug is further provided with a sealing ring, the sealing ring is in interference fit with the inner wall of the needle cylinder, and the interference magnitude in a static state is 8-10 threads.

The further preferred technical scheme is that a fluorosilicone oil lubricating layer is also adhered to the outer wall of the rubber plug.

The utility model has the advantages and the beneficial effects that: the syringe rubber plug has the advantages of simple structure, capability of automatically adjusting the sealing degree between the rubber plug and the inner wall of the barrel along with the change of the pressure in the barrel, reduction of the resistance between the rubber plug and the inner wall of the barrel, and capability of keeping sealing with the inner wall of the barrel simultaneously to avoid liquid leakage and liquid seepage. The rubber plug of the utility model is butted with the inner wall of the cylinder body and is turned and sealed through the edges of the upper sealing sheet and the lower sealing sheet, and the mutual matching effect among the arch back, the annular groove and the upper sealing sheet ensures that the rubber plug and the inner wall of the needle cylinder body are sealed and do not leak, and simultaneously reduces the frictional resistance generated between the rubber plug and the inner wall of the needle cylinder due to extrusion, and the frictional resistance is reduced to 0.1N, thereby achieving the purposes of low resistance and strong sealing; the top end of the core rod and the top end of the cavity inner ratio have a height difference, and when the cylinder is in positive pressure, the deformation amount of the rubber plug is improved, so that the extrusion force of the rubber plug on the upper sealing sheet is improved, and the sealing property of the rubber plug and the cylinder body is further improved.

Drawings

Fig. 1 is a schematic diagram of the longitudinal section structure of the rubber plug of the present invention.

In the figure: 1. a cavity; 2. a step surface; 3. an arch back; 4. an upper sealing sheet; 5. an upper annular groove; 6. a lower sealing sheet; 7. an inclined surface; 8. and (4) a sealing ring.

Detailed Description

The following description will further describe embodiments of the present invention with reference to the accompanying drawings and examples. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

As shown in fig. 1, the utility model relates to a low resistance syringe rubber plug, which is a silica gel plug and comprises a cavity 1 for accommodating a core bar at the end part of a push rod, and the inner wall of the opening of the cavity is provided with a step surface 2 matched with the core bar; the top end of the rubber plug is provided with an arch back 3 which is arched upwards, the periphery of the outer circumferential wall of the top end of the rubber plug is provided with an integrally formed upper sealing sheet 4, and the upper sealing sheet inclines outwards along the axial direction of the rubber plug; an upper annular groove 5 is arranged between the bottom edge of the arch back and the inner side surface of the upper sealing sheet; and a lower sealing sheet 6 which is symmetrical to the upper sealing sheet is arranged at the bottom end of the rubber plug. The lower bottom surface of the rubber plug is also provided with a lower annular groove. The top end of the core rod and the top end inside the cavity have a height difference, and the outer circumference of the core rod is in clearance fit with the inner wall of the circumference of the cavity.

The included angle between the upper sealing piece, the lower sealing piece and the outer circumferential surface of the rubber plug is 20 degrees.

The inner side surfaces of the edges of the upper sealing piece and the lower sealing piece are inclined surfaces 7, the included angle between the inner side surface and the outer side surface is 25 degrees, and the minimum thickness of the edges is 0.08 mm.

The width of the bottom surface of the upper annular groove is 0.35mm, and the depth of the bottom surface of the upper annular groove is 0.4 mm.

And the outer circumferential wall of the rubber plug is also provided with a sealing ring 8, the sealing ring is in interference fit with the inner wall of the needle cylinder, and the interference magnitude in a static state is 9 threads.

The rubber plug with the structure of the embodiment is 14.44mm-14.48mm in outer diameter and 50A in hardness is assembled into a PE syringe cylinder, an initial impulse force test is carried out by adopting a comprehensive tester for the performance of a syringe needle conical joint with model number 1902-e, and the test result shows that the initial impulse force of each embodiment is reduced to 0.2N, the minimum sliding force is 0.04N, the average force is 0.12N, and the syringe does not generate water drop leakage at the hydraulic pressure of 300Kpa (30 seconds).

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the technical principle of the present invention, and these improvements and decorations should also be regarded as the protection scope of the present invention.

Claims (7)

1. A low-resistance syringe rubber plug is characterized in that the rubber plug is a silica gel plug and comprises a cavity for accommodating a core rod at the end part of a push rod, and the inner wall of the opening of the cavity is provided with a step surface matched with the core rod; the top end of the rubber plug is provided with an arch back which is arched upwards, the periphery of the outer circumferential wall of the top end of the rubber plug is provided with an integrally formed upper sealing sheet, and the upper sealing sheet inclines outwards along the axial direction of the rubber plug; an upper annular groove is formed between the bottom edge of the arch back and the inner side surface of the upper sealing sheet; and the bottom end of the rubber plug is provided with a lower sealing sheet which is symmetrical to the upper sealing sheet.

2. The low resistance syringe rubber plug of claim 1 wherein there is a height difference between the top end of the core rod and the top end of the cavity interior, the outer circumference of the core rod is in clearance fit with the circumferential inner wall of the cavity.

3. The low resistance syringe rubber plug according to claim 2, wherein the included angle between the upper sealing piece, the lower sealing piece and the outer circumferential surface of the rubber plug is 10-30 °.

4. The low-resistance syringe rubber plug according to claim 3, wherein the inner side surfaces of the edges of the upper sealing sheet and the lower sealing sheet are inclined surfaces, the included angle between the inner side surface and the outer side surface is 20-30 degrees, and the minimum thickness of the edges is 0.05-0.1 mm.

5. The low resistance syringe rubber plug of claim 4 wherein the bottom surface of the upper annular groove has a width of 0.2mm to 0.5mm and a depth of 0.2mm to 0.6 mm.

6. The low-resistance syringe rubber plug according to claim 5, wherein the outer circumferential wall of the rubber plug is further provided with a sealing ring, the sealing ring is in interference fit with the inner wall of the needle cylinder, and the interference in a static state is 8-10 threads.

7. The low resistance syringe rubber plug of claim 6 wherein the outer wall of the rubber plug is further adhered with a fluorosilicone oil lubricating layer.

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