CN112354025B

CN112354025B - Disposable positive and negative pressure syringe

Info

Publication number: CN112354025B
Application number: CN202011273954.1A
Authority: CN
Inventors: 赵思含
Original assignee: Xian Jiaotong University
Current assignee: Xian Jiaotong University
Priority date: 2020-11-14
Filing date: 2020-11-14
Publication date: 2021-07-09
Anticipated expiration: 2040-11-14
Also published as: CN112354025A

Abstract

The disposable positive and negative pressure syringe comprises a syringe, a needle head, a piston and a push rod, wherein the syringe and the piston are in interference fit and have an oval structure with a rotation stopping function; fixed mounting has the nut to the inboard coaxial inlaying of piston stopper axon rear end, it has a plurality of dilatation joints to make along the axial on the nut, the nut has the axial hole, the hole is big centrum structure in little back before, and hole inner wall system has the internal thread, the nut closes the axial front end of the expansion bolt of adaptation cylinder structure soon through the internal thread, expansion bolt axle rear end links firmly as an organic wholely with push rod axle is coaxial to the front end. According to the invention, by utilizing the expansion bolt principle, the expansion bolt is screwed into the nut by rotating the push rod, so that the nut is continuously expanded, the piston is expanded, the displacement of the piston is prevented, and the effect of stable negative pressure suction is realized to suck thick liquid; can generate positive pressure and negative pressure; simple structure, convenient use and suitability for popularization.

Description

Disposable positive and negative pressure syringe

Technical Field

The invention belongs to the technical field of medical equipment, relates to an intravenous injector, and particularly relates to a disposable positive and negative pressure injector.

Background

The syringe is generally composed of a cylindrical hollow syringe, a piston push rod arranged in the hollow syringe, a fixed-distance piston arranged at the front end of the piston push rod and a needle arranged at the front end of the syringe. When the liquid sucking and pushing device is used, the piston is in interference fit with the inner wall of the needle cylinder to form a closed space, and liquid is sucked or pushed out. In the prior art, during daily diagnosis and treatment activities, when a patient is subjected to vascular puncture, seroperitoneum puncture and lump cytology biopsy, a common injector is usually adopted, and a piston push rod needs to be pulled by hands to enable the inner wall of a needle cylinder to be in interference fit with a piston, so that a closed space is formed to generate negative pressure, and effective suction can be realized. In the process, the common injector easily causes the position of the injector and the needle to move, the negative pressure suction stability is poor, the negative pressure suction effect is unstable, and the suction effect is influenced.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide a disposable positive and negative pressure injector which is designed by utilizing the expansion bolt principle, has simple structure and convenient use, and can generate positive pressure or negative pressure; the positive pressure pushes the piston rod of the syringe forward, so that the air or liquid in the syringe can be continuously pressed; when the negative pressure suction needle is used, according to the expansion bolt principle, after the needle head enters a solid part of an object, the needle head is sealed, firstly, the piston push rod of the needle cylinder is pulled backwards to generate moderate negative pressure, and then the piston push rod is rotated to enable the piston to expand and be clamped on the inner wall of the needle cylinder to generate continuous negative pressure so as to suck thick liquid.

In order to achieve the purpose, the invention adopts the technical scheme that:

the disposable positive and negative pressure syringe comprises a syringe, a needle head, a piston and a push rod, wherein the syringe and the piston are in interference fit and have an oval structure with a rotation stopping function; fixed mounting has the nut to the inboard coaxial inlaying of piston stopper axon rear end, it has a plurality of dilatation joints to make along the axial on the nut, the nut has the axial hole, the hole is big centrum structure in little back before, and hole inner wall system has the internal thread, the nut closes the axial front end of the expansion bolt of adaptation cylinder structure soon through the internal thread, expansion bolt axle rear end links firmly as an organic wholely with push rod axle is coaxial to the front end.

Preferably, the syringe, the needle, the piston, the push rod, the nut and the expansion bolt are all disposable products.

Preferably, the expansion bolts are made of hard plastic or metal.

Preferably, the piston is made of elastic material and has an elliptic cylinder structure; the needle cylinder is made of hard materials and the cavity of the needle cylinder is of an elliptic cylinder structure.

Preferably, the nut is made of hard material and fixedly connected with the piston in an embedded mode into a whole.

Preferably, the nut has a regular prism structure or a regular cylinder structure.

Preferably, the expansion gaps are arranged at the front end of the nut, and the number of the expansion gaps is one.

Preferably, the expansion blades formed between the adjacent expansion gaps are axially and symmetrically distributed along the long axis direction by taking the short axis of the elliptic piston as a symmetry axis.

Preferably, the needle cylinder is provided with a scale which is matched with the volume of the liquid contained in the needle cylinder.

Compared with the prior art, the invention has the beneficial effects that:

1. the invention carries out vascular puncture, hydrothorax and hydrops in the abdominal cavity and lump cytology biopsy on a patient, and utilizes the expansion bolt principle: firstly, drawing the push rod backwards to form negative pressure, then rotating the push rod clockwise, continuously screwing the nut by virtue of an expansion bolt at the front end of the push rod to expand the nut, so that the piston is expanded by the expanded nut, firmly limited and tightly fixed on the inner side wall of the needle cylinder at a negative pressure forming position and is fixed, continuous negative pressure is formed, and then thick liquid is sucked; the operation is stable, the negative pressure is stable, and the suction effect is excellent; when the bolt is withdrawn, the nut returns to normal state, the expansion blade of the nut is closed, the piston returns to normal volume, and the injector is used for normal positive pressure injection.

2. The design of the elliptic piston and the needle cylinder can generate torsion with the needle cylinder when the push rod rotates, so that the piston and the needle cylinder can not rotate in the same direction, and the expansion bolt can conveniently exert the expansion function; when the push rod is screwed into the nut continuously, the expanded nut is expanded to expand the piston, so that resistance is generated between the piston and the needle cylinder, the negative pressure position is stabilized, and continuous negative pressure can be generated.

3. The invention keeps the appearance and the material of a common injector, and has the advantages of production and manufacturing modes and low cost; has the functions of positive pressure injection and negative pressure stable suction; the medicine can be widely used, and has great clinical requirements; the traditional puncture mode adopts negative pressure puncture, and the inconvenience brought to clinic because a common injector cannot generate continuous negative pressure is solved; so that the puncture of blood vessels, seroperitoneum, phyma and the like is more accurate and simpler.

Drawings

FIG. 1 is a partial sectional structural schematic view of the present invention.

Fig. 2 is a schematic view of the push rod structure of the present invention.

Detailed Description

The following examples are given to facilitate a better understanding of the invention, but do not limit the invention. The following examples are only a part of the present invention, and not all of them. The components used in the following examples are commercially available unless otherwise specified.

In the present invention, unless otherwise explicitly specified or limited, unless otherwise specified or limited, the directional words "upper, lower, left, right, front, rear, inner, outer, vertical, horizontal" and the like included in the terms simply represent the orientation of the term in the normal use state, or for the convenience of describing the present invention and simplifying the description, or for the colloquial understanding of those skilled in the art, unless otherwise explicitly specified or limited, should not be construed as limiting the technical solution.

As shown in fig. 1, the disposable positive and negative pressure syringe of the present invention comprises a barrel 1, a needle 2, a piston 3 and a plunger 4.

The improvement of the invention lies in that: the syringe 1 and the piston 3 are in interference fit and have an oval structure with a rotation stopping function. In the above embodiment, preferably: the piston 3 is made of elastic material and has an elliptic cylinder structure; the needle cylinder 1 is made of hard material and the cavity is an elliptic cylinder structure.

According to the design of the elliptic piston 3 and the needle cylinder 1, when the push rod 4 rotates, torsion can be generated between the push rod and the needle cylinder 1, so that the piston 3 and the needle cylinder 1 can not rotate in the same direction, and an expansion bolt 6 described later can conveniently exert the expansion function; when the push rod 4 is continuously screwed into the nut 5, the nut 5 expanding the expansion expands the piston 3, the piston 3 expands, so that great resistance is generated between the piston 3 and the inner side wall of the needle cylinder 1, the negative pressure position is stabilized, continuous negative pressure can be generated, and thick liquid can be conveniently and stably pumped.

Namely, the piston 3 is coaxially embedded and fixed with a mounting nut 5 at the inner side of the rear end of the axial body. In the above embodiment, preferably: the nut 5 is made of hard material, and the shape thereof is a regular cylinder structure and is fixedly connected with the piston 3 in an embedded manner.

Or: in the above embodiment, preferably: the nut 5 is made of hard material, and the shape thereof is a regular prism structure and is fixedly connected with the piston 3 in an embedded manner.

On the basis, an expansion joint 501 is axially formed on the nut 5; in the above embodiment, preferably: the front end of the nut 5 is provided with 2-4 expansion gaps 501; the expansion blades formed by the adjacent expansion gaps 501 are axisymmetrically distributed along the long axis direction with the short axis of the elliptical piston 3 as the symmetry axis to stabilize axisymmetric expansion.

The nut 5 is provided with a through axial inner hole which is in a cone structure with a small front part and a big back part, the inner wall of the inner hole is provided with an internal thread 502 (the direction is shown in figure 1, the front part is the left part, the back part is the right part), and the axial front end of the expansion bolt 6 which is matched with the cylindrical structure is screwed through the internal thread 502; the rear end of the expansion bolt 6 is coaxially and fixedly connected with the front end of the push rod 4 into a whole, as shown in figure 2. The nut 5 is expanded by screwing the internal thread 502 formed in the nut 5 through the expansion bolt 6.

In the above embodiment, preferably: the expansion bolts 6 are made of hard plastic or metal.

In the above embodiment, preferably: the syringe 1, the needle head 2, the piston 3, the push rod 4, the nut 5 and the expansion bolt 6 are all disposable products.

On the basis, the scale made on the syringe 1 is matched with the volume of the liquid contained in the syringe.

The working principle of the invention is as follows: the invention carries out vascular puncture, hydrothorax and hydrops in the abdominal cavity and lump cytology biopsy on a patient, and utilizes the expansion bolt principle: after the needle head 2 is inserted into the solid tissue, the push rod 4 is firstly pulled backwards to form negative pressure; then the push rod 4 is rotated clockwise, the nut 5 with the internal thread taper hole is gradually expanded by continuously screwing the expansion bolt 6 at the front end of the push rod 4 into the nut 5, so that the piston 3 is expanded by the expanded nut 5, the piston 3 is firmly limited and tightly fixed at the negative pressure forming position of the inner side wall of the needle cylinder 1, continuous negative pressure is formed, and then thick liquid is sucked; the operation is stable, the negative pressure suction is stable, and the suction effect is excellent; when the expansion bolt 6 is spirally withdrawn, the nut 5 is recovered to be in a normal state, the expansion blade of the nut 5 is closed, the piston 3 is recovered to be in a normal volume, and the injector is normally injected by positive pressure.

From the above description it can be found that: the invention keeps the appearance and the material of a common injector, and has the advantages of production and manufacturing modes and low cost; has the functions of positive pressure injection and negative pressure stable suction; the medicine can be widely used, and has great clinical requirements; the traditional puncture mode adopts negative pressure puncture, and the inconvenience brought to clinic because a common injector cannot generate continuous negative pressure is solved; so that the puncture of blood vessels, seroperitoneum, lumps and the like is more accurate, simple and stable.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description is described in terms of one embodiment, this embodiment does not include only a single embodiment, but such description is merely for clarity, and those skilled in the art will recognize that the embodiments described in this embodiment can be combined as appropriate to form other embodiments as would be understood by those skilled in the art.

The above-mentioned embodiments are merely preferred embodiments of the present invention, which are not intended to limit the scope of the present invention, and therefore, all equivalent changes made by the contents of the claims of the present invention should be included in the claims of the present invention.

Claims

1. The disposable positive and negative pressure syringe comprises a syringe (1), a needle head (2), a piston (3) and a push rod (4), and is characterized in that the syringe (1) and the piston (3) are in interference fit and have an oval structure with a rotation stopping function; piston (3) stopper body axle is to inboard coaxial fixed mounting of inlaying of rear end has nut (5), it has a plurality of expansion joints (501) to go up along axial system in nut (5), nut (5) have the axial hole, the hole is big centrum structure in the front and back, and hole inner wall system has internal thread (502), nut (5) close the axial front end of expansion bolt (6) of adaptation cylinder structure soon through internal thread (502), expansion bolt (6) axial rear end links firmly as an organic whole with push rod (4) axial front end is coaxial.

2. The disposable positive and negative pressure syringe as claimed in claim 1, wherein the barrel (1), needle (2), piston (3), plunger (4), nut (5), and expansion bolt (6) are all disposable articles.

3. The disposable positive and negative pressure syringe according to claim 1 or 2, wherein the expansion bolt (6) is made of hard plastic or metal.

4. The disposable positive and negative pressure syringe according to claim 1 or 2, wherein the piston (3) is made of an elastic material and has an outer shape of an elliptic cylinder structure; the needle cylinder (1) is made of hard materials, and the cavity of the needle cylinder is of an elliptic cylinder structure.

5. The disposable positive and negative pressure syringe as claimed in claim 1 or 2, wherein the nut (5) is made of hard material and is fixedly connected with the piston (3) in an embedded manner.

6. The disposable positive and negative pressure syringe according to claim 5, wherein the nut (5) has a regular prism structure or a regular cylinder structure in its outer shape.

7. The disposable positive and negative pressure syringe as claimed in claim 1, wherein the expansion slits (501) are provided at the front end of the nut (5) in a number of 2-4.

8. The disposable positive and negative pressure syringe as claimed in claim 1 or 7, wherein the expansion blades formed between the adjacent expansion slits (501) are axisymmetrically distributed in the direction of the major axis with the minor axis of the elliptical piston (3) as the axis of symmetry.

9. The disposable positive and negative pressure syringe according to claim 1, wherein the needle cylinder (1) is graduated to match the volume of liquid contained therein.