CN220546445U

CN220546445U - Needle tip shielding type indwelling needle

Info

Publication number: CN220546445U
Application number: CN202222545378.2U
Authority: CN
Inventors: 于尚在; 于文敏; 王驰
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-09-26
Filing date: 2022-09-26
Publication date: 2024-03-01
Anticipated expiration: 2032-09-26

Abstract

A needle tip shielding type indwelling needle relates to the indwelling needle field, and comprises a three-way joint, a connecting catheter, a sleeve seat, a needle handle, a hemostatic sealing plug, a puncture needle tube, a needle following device, a sleeve and a sheath, wherein the front end of the sleeve seat is provided with a sleeve connecting hole, and a mounting cavity with an open rear end is arranged in the sleeve seat at the rear side of the sleeve connecting hole; the rear part of the sleeve is inserted in the sleeve connecting hole, the connecting catheter is communicated with the mounting cavity through the injection joint, a protective cap is arranged in the mounting cavity between the hemostatic sealing plug and the needle handle, the protective cap can be sleeved on the puncture needle tube in an axial sliding manner along the puncture needle tube, a traction wire is arranged between the rear end of the protective cap and the needle handle, the length of the traction wire is smaller than that of the puncture needle tube at the front side of the needle handle, and the sum of the length of the traction wire and the thickness of the protective cap is not smaller than that of the puncture needle tube at the front side of the needle handle. Has the advantages of simple structure, low cost, same appearance as the common Y-shaped indwelling needle, unchanged operation technique during use, simple operation and the like.

Description

Needle tip shielding type indwelling needle

Technical Field

The utility model relates to the field of indwelling needles, in particular to a needle tip shielding type indwelling needle which is simple in structure, low in cost, identical in appearance with a common Y-type indwelling needle, unchanged in operation method and simple in operation during use.

Background

The needle is used as an emerging transfusion tool for more than ten years to be widely applied clinically, and particularly, the method for transfusion of inpatients by the transfusion device is replaced to a great extent for the inpatients, and the transfusion device is characterized in that after a plastic soft sleeve is punctured by a steel needle and is brought into a vein of a human body, a puncture needle tube is drawn out, the sleeve is reserved in the human body, and next transfusion is directly performed through the sleeve reserved in the human body to connect the transfusion device without puncture, so that the transfusion device has the advantages that: the pain caused by repeated puncture can be reduced for the patient, and the workload can be greatly reduced for medical staff, so that the indwelling needle is widely accepted by doctors and patients and can be kept for a long time in the future.

The most common indwelling needle used clinically at present is a Y-shaped indwelling needle, the Y-shaped indwelling needle comprises a three-way joint, a connecting catheter, a sleeve seat, a needle handle, a hemostatic sealing plug, a puncture needle tube, a needle following device, a sleeve and a sheath, the front end of the sleeve seat is provided with a sleeve connecting hole, a sleeve seat at the rear side of the sleeve connecting hole is internally provided with a mounting cavity with an open rear end, and the mounting cavity is excessively connected with the sleeve connecting hole through a horn-shaped needle following hole; the rear part of the sleeve is inserted into the sleeve connecting hole, the needle following device is in a funnel shape and is in interference fit with the needle following hole, the front part of the needle following device is inserted into the rear end part of the sleeve, the rear end part of the sleeve is extruded and fixed in the sleeve connecting hole, the puncture needle tube is arranged in the sleeve in a penetrating way, the front end of the sleeve is contracted and tightly attached to the puncture needle tube, the hemostatic sealing plug is arranged in the mounting cavity at the rear side of the needle following device, the puncture needle tube is sealed with the inner side of the mounting cavity, the needle handle cover is arranged at the rear end of the mounting cavity, and the rear end of the puncture needle tube is fixedly connected with the needle handle; an injection joint is arranged on a sleeve seat between the hemostatic sealing plug and the needle following device, a connecting catheter is communicated with the inside of the installation cavity through the injection joint, a three-way joint is arranged at the other end of the connecting catheter, and a heparin cap and a protective cap are arranged on the three-way joint.

The existing production method of the Y-shaped indwelling needle comprises the following steps: inserting the front part of the needle following device into the rear end part of the sleeve, putting the front end of the sleeve into the sleeve connecting hole from the opening of the rear end of the mounting cavity forwards through the mounting cavity, pressing the needle following device forwards, and pressing the front end of the needle following device into the sleeve connecting hole; the rear end of the puncture needle tube is fixedly connected with the needle handle in a dispensing way after puncturing the hemostatic sealing plug; the front end of the puncture needle tube is placed into the sleeve from the opening at the rear end of the installation cavity forwards through the installation cavity and the needle following device, the hemostatic sealing plug is extruded into the sleeve seat, and the needle handle cover is arranged on the opening at the rear end of the installation cavity.

When the existing Y-shaped indwelling needle puncture needle tube is withdrawn after the puncture is finished, the needle point is exposed outside, and the puncture needle tube is easy to stab others due to sharpness of the puncture needle tube which is slightly careless; in recent years, there are many cases at home and abroad, especially when patients are infected with infectious diseases, so a safety measure for preventing the needle tip from stabbing other people is desired clinically, and for this reason, manufacturers have produced the products, such as: the utility model and creation name disclosed by the national intellectual property office is: the needle tube retraction type venous indwelling needle has the following application number: 201620262783.5, the utility model and the creative name are: a needle tube retraction type indwelling needle, application number is: 201720818622.4, while solving the disadvantages that the needle tip of the puncture needle tube is easy to stab others and causes cross infection risk when the puncture needle tube is withdrawn after the puncture is completed, has at least one of the disadvantages of complex structure, high manufacturing cost, large difference from the appearance of the conventional indwelling needle, changed operation technique, increased operation difficulty and the like. These problems are difficult to popularize and apply in a large area in the market.

Disclosure of Invention

The utility model aims to solve the defects of the prior art, and provides the needle tip shielding type indwelling needle which has the advantages of simple structure, low cost, same appearance as the commonly used Y-shaped indwelling needle, unchanged operation method and simple operation during use.

The technical scheme of the utility model is as follows:

a needle tip shielding type indwelling needle comprises a three-way joint, a connecting catheter, a cannula holder, a needle handle, a hemostatic sealing plug, a puncture needle tube, a needle following device, a cannula and a sheath, wherein the front end of the cannula holder is provided with a cannula connecting hole, an installation cavity with an open rear end is arranged in the cannula holder at the rear side of the cannula connecting hole, and the installation cavity is excessively connected with the cannula connecting hole through a horn-shaped needle following hole; the rear part of the sleeve is inserted into the sleeve connecting hole, the needle following device is in a funnel shape and is in interference fit with the needle following hole, the front part of the needle following device is inserted into the rear end part of the sleeve, the rear end part of the sleeve is extruded and fixed in the sleeve connecting hole, the puncture needle tube is arranged in the sleeve in a penetrating way, the front end of the sleeve is contracted and tightly attached to the puncture needle tube, the hemostatic sealing plug is arranged in the mounting cavity at the rear side of the needle following device, the puncture needle tube is sealed with the inner side of the mounting cavity, the needle handle cover is arranged at the rear end of the mounting cavity, and the rear end of the puncture needle tube is fixedly connected with the needle handle; an injection joint is arranged on a sleeve seat between the hemostatic sealing plug and the needle following device, a connecting catheter is communicated with the inside of the installation cavity through the injection joint, a three-way joint is arranged at the other end of the connecting catheter, and a heparin cap and a protective cap are arranged on the three-way joint; the hemostatic needle is characterized in that a protective cap is arranged in a mounting cavity between the hemostatic sealing plug and the needle handle, the protective cap can be sleeved on the puncture needle tube in an axial sliding manner along the puncture needle tube, a pull wire is arranged between the rear end of the protective cap and the needle handle, the length of the pull wire is smaller than that of the puncture needle tube at the front side of the needle handle, and the sum of the length of the pull wire and the thickness of the protective cap is not smaller than that of the puncture needle tube at the front side of the needle handle. The sheath is sleeved and fixed at the front part of the sleeve seat and is protected at the outer sides of the puncture needle tube and the sleeve.

According to the utility model, the hemostatic sealing plug is cylindrical, one side of the hemostatic sealing plug is provided with a needle tube inserting notch which is axially and radially communicated, and the puncture needle tube is inserted into the center of the hemostatic sealing plug from one side of the hemostatic sealing plug through the needle tube inserting notch. The size of the needle tube placement notch in the radial direction of the hemostatic plug is the radius of the hemostatic plug plus the radius of the puncture needle tube, and the puncture needle tube can be extruded into the center of the hemostatic plug through the needle tube placement notch and is coaxial with the hemostatic plug. The connection process of puncture needle tubing and hemostasis sealing plug does not destroy the inside tissue of hemostasis sealing plug, and sealed effectual, after the needle tubing is taken out, the condition of leaking blood leakage can never appear, proves through actual detection experiment that hemostasis sealing plug axial length can reach sealed hemostatic purpose at 1 millimeter, but in actual production, in order simple to operate, prevent unexpected emergence, hemostasis sealing plug axial length usually selects 2-4 millimeters, preferably 3 millimeters. The axial length of the hemostatic sealing plug of the existing Y-shaped indwelling needle is usually 6 mm. The structure can save the space in the installation cavity and provide space for the installation of the protective cap.

The protective cap is in a bottle cap shape with an open rear side, the middle part of the front side wall of the protective cap is provided with a needle tube sliding hole matched with the puncture needle tube, and the puncture needle tube can freely slide back and forth to pass through the needle tube sliding hole.

The protective cap is contacted with the inner wall of the installation cavity, and the friction force between the protective cap and the inner wall of the installation cavity is 0.1-10N, preferably 0.5-1N.

The front end of the protective cap and the rear end of the hemostatic sealing plug are provided with the stressed separating connecting piece, and when the stressed separating connecting piece is stressed to exceed the connecting force, the protective cap is separated from the hemostatic sealing plug; the joining force is 0.1 to 10N, preferably 0.5 to 1N.

The stressed separating connecting piece is characterized in that dispensing is arranged between the front end of the protective cap and the rear end of the hemostatic sealing plug, and the front end of the protective cap is partially bonded with the rear end of the hemostatic sealing plug; when the tensile separating force between the front end of the protective cap and the rear end of the hemostatic sealing plug is larger than the bonding force, the bonding fails and the protective cap is separated from the hemostatic sealing plug.

The stressed separating connector is characterized in that a plug-in connecting column is arranged on one side of the front end of the protective cap, a plug-in hole matched with the plug-in connecting column is arranged on the rear end of the hemostatic sealing plug, and the plug-in connecting column is inserted into the plug-in hole in interference fit. The force generated by interference fit between the plug connection column and the plug hole is the connection force; the axial stretching separating force between the protective cap and the hemostatic sealing plug is larger than the force generated by the interference fit between the plug connection post and the plug hole, and the protective cap and the hemostatic sealing plug are separated.

A traction wire is arranged between one side of the rear end of the protective cap and the same side of the needle handle, and the stressed separation connecting piece is arranged between the protective cap and the hemostatic sealing plug on the side opposite to the traction wire. In the process that the needle handle pulls the protective cap backwards through the pulling wire, before the protective cap is not separated from the hemostatic sealing plug, the pulling wire can pull the protective cap to incline so that the tip end of the puncture needle tube is not opposite to the needle tube sliding hole, and when the pulling wire pulls the protective cap to be separated from the hemostatic sealing plug, the tip end part of the puncture needle tube is inserted into the side wall of the protective cap. The protection effect is better.

A traction wire is arranged between one side of the rear end of the protective cap and the same side of the needle handle, an auxiliary wire is arranged between the rear end of the protective cap and the needle handle, and the length of the auxiliary wire is 0.3-3 mm, preferably 1-2 mm, greater than that of the traction wire. After the traction wire pulls the protective cap to incline, so that the tip of the puncture needle tube is not opposite to the sliding hole of the needle tube, the auxiliary traction wire and the traction wire pull the protective cap backwards in the installation cavity together, and the dangerous condition that the tip of the puncture needle tube punctures the protective cap is possibly even caused by unstable friction force between the protective cap and the inner wall of the installation cavity and large change of the relative position between the tip of the puncture needle tube and the protective cap after the protective cap is excessively deformed due to unilateral traction of the traction wire is avoided.

The side protective cap is made of rubber materials. The protective cap has certain elasticity, and the tip of the puncture needle tube can be partially penetrated into the protective cap.

The axial dimension of the protective cap is 2-8 mm, preferably 3-5 mm; the wall thickness of the protective cap is 0.5-2 mm, preferably 1-1.5 mm; the length of the traction wire is 1-3 mm, preferably 1.5-2.5 mm, smaller than the length of the puncture needle tube at the front side of the needle handle; the sum of the length of the pulling wire and the thickness of the protective cap is 0.1-3 mm, preferably 0.6-2 mm, greater than the length of the puncture needle tube at the front side of the needle handle.

The tip of the puncture needle tube is positioned on the opposite side of the pull wire.

The stressed separation connecting piece is arranged between the protective cap and the hemostatic sealing plug at the opposite side of the traction wire. In the process that the needle handle pulls the protective cap backwards through the pulling wire, before the protective cap is not separated from the hemostatic sealing plug, the pulling wire can pull the protective cap to incline so that the tip end of the puncture needle tube is not opposite to the needle tube sliding hole, and when the pulling wire pulls the protective cap to be separated from the hemostatic sealing plug, the tip end part of the puncture needle tube is inserted into the side wall of the protective cap. The protection effect is better.

The traction wire is a twine, a cotton wire or a medical suture.

The inner diameter of the protective cap is 2-6 times of the diameter of the needle tube slide hole. Preferably 3-4 times.

According to the utility model, the needle handle is further improved, the front side of the needle handle is provided with a needle tube assembly hole, the front part of the needle tube assembly hole is provided with a dispensing hole in the shape of a reverse cone, and the needle handle at one side of the needle tube assembly hole is provided with a radial glue storage hole communicated with the dispensing hole. The effect of uniformly distributing 2-3 radial glue storage holes on the circumference of the needle tube assembly hole is better. The needle handle is provided with a needle tube assembly hole on the front side, a dispensing hole in a reverse cone is arranged at the front part of the needle tube assembly hole, when the needle handle is assembled, kong Nadian glue is dispensed firstly, and after a puncture needle tube is inserted into the needle tube assembly hole from the dispensing hole, the glue is mainly accumulated at the dispensing hole. The connection firmness of the puncture needle tube and the needle handle is required to be technical, and the separation force of the puncture needle tube and the needle handle is not less than 30N, so that the needle tube is prevented from falling off in a human body when being pulled out after the puncture is completed; to ensure this separation force, the reverse taper of the cylindrical portion of the needle shaft must be sufficiently large and deep, i.e., axially long. From the condition of the current product drawing and separating experiment, the whole puncture needle tube is connected with glue together and is separated from the glue dispensing hole of the inverted cone. According to the radial glue storage hole, the dried glue is not easy to separate from the glue dispensing hole, the connection firmness of the puncture needle tube and the needle handle is improved, and the product drawing and separating experiment proves that the separation force of the puncture needle tube and the needle handle is above 50N and most of the dried glue is separated from the puncture needle tube due to the arrangement of the glue dispensing hole. This structure cooperates with the pulling force demand of protective cap, prevents to increase the protective cap structure after, will puncture needle tubing and pull out the unexpected emergence that in-process pulling force increased and led to needle handle and puncture needle tubing to separate.

The preparation method of needle tip shielding type indwelling needle comprises the steps of inserting the front part of a needle following device into the rear end part of a sleeve, putting the front end of the sleeve into a sleeve connecting hole from an opening at the rear end of a mounting cavity forwards through the mounting cavity, pressing the needle following device forwards, and pressing the front end of the needle following device into the sleeve connecting hole; is characterized in that one side of the puncture needle tube is placed in the center of the hemostatic sealing plug through the needle tube placement notch; the protective cap is sleeved on the puncture needle tube through the rear end of the puncture needle tube; the two ends of the traction wire are fixedly connected with the rear end of the protective cap and the needle handle respectively; the rear part of the puncture needle tube is fixedly connected with the needle handle in a dispensing way; the front end of the puncture needle tube is placed into the sleeve tube from the opening at the rear end of the installation cavity forwards through the installation cavity and the needle following device, the hemostatic sealing plug and the protective cap are extruded into the sleeve tube seat together, and the needle handle cover is arranged on the opening at the rear end of the installation cavity.

When the utility model is used, all operation methods are the same as the existing Y-shaped indwelling needle. After the puncture is completed, when the puncture needle tube is withdrawn, the traction wire is continuously unfolded along with the withdrawal of the needle handle and the puncture needle tube, when the needle point of the puncture needle tube enters the protective cap, the traction wire is straightened, and when the puncture needle tube is continuously withdrawn, the traction wire pulls the protective cap backwards; when the protective cap is completely separated from the sleeve seat, the protective cap is shifted due to the fact that the pulling wire is pulled on one side, the hole, matched with the puncture needle tube, on the protective cap after shifting is not opposite to the needle point, and the needle point cannot be exposed, so that the protective effect is achieved. The utility model has the advantages of simple structure, low cost, same appearance as the common Y-shaped indwelling needle, unchanged operation technique during use, simple operation and the like.

Drawings

Fig. 1 is a schematic structural view of the present utility model.

Fig. 2 is a partial enlarged view at a of fig. 1.

Fig. 3 is a schematic view of yet another construction of the present utility model.

Fig. 4 is a partial enlarged view at B of fig. 3.

Figure 5 is a schematic cross-sectional view of a hemostatic plug according to the utility model.

Fig. 6 is a schematic structural view of the helmet of the present utility model.

Fig. 1 and 2 are schematic structural diagrams of embodiment 1; fig. 3 and 4 are schematic structural diagrams of embodiment 2.

Detailed Description

The utility model is further described below with reference to the accompanying drawings:

example 1

The needle tip shielding type indwelling needle shown in fig. 1 and 2 comprises a three-way joint 13, a connecting catheter 11, a sleeve seat 5, a needle handle 8, a hemostatic sealing plug 10, a puncture needle tube 2, a needle following device 4, a sleeve 3 and a sheath 1, wherein the front end of the sleeve seat 5 is provided with a sleeve connecting hole, a mounting cavity 6 with an open rear end is arranged in the sleeve seat 5 at the rear side of the sleeve connecting hole, and the mounting cavity 6 is excessively connected with the sleeve connecting hole through a horn-shaped needle following hole; the rear part of the sleeve 3 is inserted into a sleeve connecting hole, the needle following device 4 is in a funnel shape and is in interference fit with a needle following hole, the front part of the needle following device 4 is inserted into the rear end part of the sleeve 3, the rear end part of the sleeve 3 is extruded and fixed in the sleeve connecting hole, the puncture needle tube 2 is arranged in the sleeve 3 in a penetrating way, the front end of the sleeve 3 is shrunk and tightly attached to the puncture needle tube 2, the hemostatic sealing plug 10 is arranged in the mounting cavity 6 at the rear side of the needle following device 4, the puncture needle tube 2 is sealed with the inner side of the mounting cavity 6, the needle handle 8 is covered on the opening at the rear end of the mounting cavity 6, and the rear end of the puncture needle tube 2 is fixedly connected with the needle handle 8; an injection joint 7 is arranged on one side of the sleeve seat 5 between the hemostatic sealing plug 10 and the needle following device 4, a connecting conduit 11 is communicated with the inside of the installation cavity 6 through the injection joint 7, the other end of the connecting conduit 11 is connected with a three-way joint 13, and a heparin cap and a protective cap are arranged on the three-way joint 13 and used for an injector; a hemostatic clamp 12 is arranged on the connecting catheter 11; the above structure is the same as the prior art and will not be described again. The utility model is characterized in that a protective cap 9 is arranged in a mounting cavity 6 between a hemostatic sealing plug 10 and a needle handle 8, the protective cap 9 can be sleeved on a puncture needle tube 2 in a freely sliding way along the axial direction of the puncture needle tube, the protective cap 9 is in a bottle cap shape with an open rear side, the middle part of the front side wall of the protective cap is provided with a needle tube sliding hole 20 matched with the puncture needle tube 2, and the puncture needle tube 2 can freely slide back and forth through the needle tube sliding hole 20; the inner part 17 of the bottle cap-shaped protective cap 9 is a protective cavity, and as can be seen from fig. 6, the section of the protective cavity 17 is in a trapezoid shape with a small front part and a large rear part, the inner diameter of the protective cap (the diameter of the protective cavity 17) is 3-4 times of the diameter of the needle tube slide hole 20, and the protective cap is more beneficial to penetrating through the needle tube tip to enter the protective cavity and covering and protecting the needle tube tip after being inclined. In this embodiment, the puncture needle tube 2 is in clearance fit with the needle tube sliding hole 20, the protective cap is in clearance fit with the installation cavity of the sleeve seat, and the clearance between the puncture needle tube and the needle tube sliding hole is larger than the clearance between the protective cap and the sleeve seat. A traction wire 15 is arranged between one side of the rear end of the protective cap 9 and the front side of the needle handle 8 in the mounting cavity, the length of the traction wire between the rear end of the protective cap 9 and the front side of the needle handle 8 in the mounting cavity is smaller than the length of the puncture needle tube of the needle handle on the front side of the mounting cavity, and the sum of the length of the traction wire and the thickness of the protective cap (the dimension of the protective cap in the axial direction of the puncture needle tube) is not smaller than the length of the puncture needle tube of the needle handle on the front side of the mounting cavity; as can be seen in fig. 2, the traction wire 15 is bent inside the protection cavity. The sheath 1 is sleeved and fixed at the front part of the sleeve seat and is protected at the outer sides of the puncture needle tube and the sleeve, and the tip of the puncture needle tube is protected by the sheath 1 before the use.

According to a further improvement of the embodiment, the puncture needle tube 2 is in clearance fit with the needle tube sliding hole 20, the protective cap is in interference fit with the installation cavity of the sleeve seat, the protective cap is in contact with the inner wall of the installation cavity, the friction force between the protective cap and the inner wall of the installation cavity when the protective cap axially slides in the installation cavity is 1N-3N, and the static friction force between the protective cap and the inner wall of the installation cavity is not more than 5N. As can be seen from fig. 2 and 6, the cross section of the bottle cap-shaped protective cap 9 is trapezoid with small front and large rear, so that the friction force between the protective cap and the sleeve seat can be controlled conveniently; the structure can effectively prevent the protective cap from being pulled out from the rear end of the installation cavity in advance in the process of pulling out the puncture needle tube 2, and prevent the protective failure caused by slight adhesion or knotting of the traction wire. An auxiliary wire is arranged between the rear end of the protective cap and the needle handle at the opposite side of the traction wire, the auxiliary wire and the traction wire 15 are symmetrically arranged at the left side and the right side of the puncture needle tube 2, and the length of the auxiliary wire is 1-2 mm longer than that of the traction wire; after the traction wire pulls the protective cap to incline, so that the tip of the puncture needle tube is not opposite to the sliding hole of the needle tube, the auxiliary traction wire and the traction wire pull the protective cap backwards in the installation cavity together, and the dangerous condition that the protective cap is punctured by the tip of the puncture needle tube even is possibly caused by unstable friction force between the protective cap and the inner wall of the installation cavity and large change of the relative position between the tip of the puncture needle tube after the traction wire is pulled on one side to deform the protective cap is avoided.

According to the utility model, the hemostatic sealing plug 10 is in a cylindrical shape matched with the inner wall of the mounting cavity, one side of the hemostatic sealing plug 10 is provided with a needle tube inserting notch 19 which is axially (front and back) communicated and radially arranged, and the puncture needle tube 2 is inserted into the center of the hemostatic sealing plug from one side of the hemostatic sealing plug 10 through the needle tube inserting notch 19; the needle insertion notch 19 is a slit cut in the radial direction thereof on one side of the hemostatic plug 10. The size of the needle tube placement notch in the radial direction of the hemostatic plug is the radius of the hemostatic plug plus the radius of the puncture needle tube, and the puncture needle tube can be extruded into the center of the hemostatic plug through the needle tube placement notch and is coaxial with the hemostatic plug. The connection process of the puncture needle tube and the hemostatic sealing plug does not damage tissues in the hemostatic sealing plug, the sealing effect is good, when the needle tube is withdrawn, the condition of blood leakage and liquid leakage can not occur, and the practical detection experiment proves that the axial length of the hemostatic sealing plug can achieve the aim of sealing hemostasis at 1 millimeter, and in practical production, the axial length of the hemostatic sealing plug is usually 2-5 millimeters, preferably 3-4 millimeters, for the convenience of installation and the prevention of accidents. The axial length of the hemostatic sealing plug of the existing Y-shaped indwelling needle is usually 6-8 mm. The structure can save the space in the installation cavity and provide space for the installation of the protective cap.

Example 2

The needle tip shielding type indwelling needle shown in fig. 3 and 4 comprises a three-way joint 13, a connecting catheter 11, a sleeve seat 5, a needle handle 8, a hemostatic sealing plug 10, a puncture needle tube 2, a needle following device 4, a sleeve 3 and a sheath 1, wherein the front end of the sleeve seat 5 is provided with a sleeve connecting hole, the sleeve seat 5 at the rear side of the sleeve connecting hole is internally provided with a mounting cavity 6 with an open rear end, and the mounting cavity 6 is excessively connected with the sleeve connecting hole through a horn-shaped needle following hole; the rear part of the sleeve 3 is inserted into a sleeve connecting hole, the needle following device 4 is in a funnel shape and is in interference fit with a needle following hole, the front part of the needle following device 4 is inserted into the rear end part of the sleeve 3, the rear end part of the sleeve 3 is extruded and fixed in the sleeve connecting hole, the puncture needle tube 2 is arranged in the sleeve 3 in a penetrating way, the front end of the sleeve 3 is shrunk and tightly attached to the puncture needle tube 2, the hemostatic sealing plug 10 is arranged in the mounting cavity 6 at the rear side of the needle following device 4, the puncture needle tube 2 is sealed with the inner side of the mounting cavity 6, the needle handle 8 is covered on the opening at the rear end of the mounting cavity 6, and the rear end of the puncture needle tube 2 is fixedly connected with the needle handle 8; an injection joint 7 is arranged on one side of the sleeve seat 5 between the hemostatic sealing plug 10 and the needle following device 4, a connecting conduit 11 is communicated with the inside of the installation cavity 6 through the injection joint 7, the other end of the connecting conduit 11 is connected with a three-way joint 13, and a heparin cap and a protective cap are arranged on the three-way joint 13 and used for an injector; a hemostatic clamp 12 is arranged on the connecting catheter 11; the above structure is the same as the prior art and will not be described again. The utility model is characterized in that a protective cap 9 is arranged in a mounting cavity 6 between a hemostatic sealing plug 10 and a needle handle 8, the protective cap 9 can be sleeved on a puncture needle tube 2 in a freely sliding way along the axial direction of the puncture needle tube, the protective cap 9 is in a bottle cap shape with an open rear side, the middle part of the front side wall of the protective cap is provided with a needle tube sliding hole 20 matched with the puncture needle tube 2, and the puncture needle tube 2 can freely slide back and forth through the needle tube sliding hole 20; the inner part 17 of the bottle cap-shaped protective cap 9 is a protective cavity, and as can be seen from fig. 6, the section of the protective cavity 17 is in a trapezoid shape with a small front part and a large rear part, the inner diameter of the protective cap (the diameter of the protective cavity 17) is 3-4 times of the diameter of the needle tube slide hole 20, and the protective cap is more beneficial to penetrating through the needle tube tip to enter the protective cavity and covering and protecting the needle tube tip after being inclined. In the embodiment, the puncture needle tube 2 is in clearance fit with the needle tube sliding hole 20, the protective cap is in clearance fit with the installation cavity of the sleeve seat, a stress separation connecting piece is arranged between the front end of the protective cap 9 and the rear end of the hemostatic sealing plug 10, and when the stress separation connecting piece receives (axial) tensile force exceeding the connecting force, the protective cap is separated from the hemostatic sealing plug; the joining force is 0.1 to 10N, preferably 1 to 3N. As can be seen from fig. 4, the stressed release connector in the utility model is that a plug-in connection column 16 is arranged on one side of the front end of the protective cap 9, a plug-in hole matched with the plug-in connection column 16 is arranged on the rear end of the hemostatic sealing plug, and the plug-in connection column 16 is inserted into the plug-in hole in an interference fit manner. The force generated by the interference fit of the plug connection column 16 and the plug insertion hole, which can overcome the axial pulling and separate the plug connection column from the plug insertion hole, is a connecting force; the axial stretching separating force between the protective cap and the hemostatic sealing plug is greater than the force generated by interference fit between the plug connection column and the plug hole, and the protective cap and the hemostatic sealing plug are separated; the structure can effectively prevent the protective cap from being pulled out from the rear end of the installation cavity in advance in the process of pulling out the puncture needle tube 2, before the protective cap is separated from the hemostatic sealing plug, the traction wire 15 is straightened and tightened, the tip of the puncture needle tube enters the protective cavity 17, after the protective cap is pulled and inclined, the protective cap is separated from the hemostatic sealing plug, the tip of the puncture needle tube is inserted on the side wall of the protective cap under the action of elasticity and tension, and the protective failure caused by slight adhesion or knotting of the traction wire can be effectively prevented, so that the protective effect is better. A traction wire 15 is arranged between one side of the rear end of the protective cap 9 and the front side of the needle handle 8 in the mounting cavity, the length of the traction wire between the rear end of the protective cap 9 and the front side of the needle handle 8 in the mounting cavity is smaller than the length of the puncture needle tube of the needle handle on the front side of the mounting cavity, and the sum of the length of the traction wire and the thickness of the protective cap (the dimension of the protective cap in the axial direction of the puncture needle tube) is not smaller than the length of the puncture needle tube of the needle handle on the front side of the mounting cavity; as can be seen in fig. 4, the traction wire 15 is arranged bent inside the protection cavity. The stressed separating connecting piece can also be formed by setting adhesive dots between one side of the front end of the protective cap and the rear end of the hemostatic sealing plug, and locally bonding the front end of the protective cap and the rear end of the hemostatic sealing plug, namely bonding the protective cap and the hemostatic sealing plug in an adhesive dot manner, wherein the bonding force is a connecting force; when the tensile separating force between the front end of the protective cap and the rear end of the hemostatic sealing plug is larger than the bonding force, the bonding fails and the protective cap is separated from the hemostatic sealing plug.

A traction wire is arranged between one side of the rear end of the protective cap and the front side of the needle handle in the installation cavity, the stress separation connecting piece is arranged between the protective cap and the hemostatic sealing plug on the side opposite to the traction wire, namely, the traction wire and the stress separation connecting piece are arranged on two sides of the puncture needle tube. In the process that the needle handle pulls the protective cap backwards through the pulling wire, before the protective cap is not separated from the hemostatic sealing plug, the pulling wire can pull the protective cap to incline so that the tip of the puncture needle tube is not opposite to the needle tube sliding hole (the tip of the puncture needle tube is opposite to the inner wall of the protective cap), and when the pulling wire pulls the protective cap to be separated from the hemostatic sealing plug, the tip part of the puncture needle tube is inserted into the side wall of the protective cap; the protection effect is better.

The protective cap is made of rubber materials. The protective cap has certain elasticity, and the tip of the puncture needle tube can be partially penetrated into the protective cap.

The tip of the puncture needle tube is positioned at the opposite side of the traction wire, and the tip of the puncture needle tube and the traction wire are respectively positioned at the two sides of the axis of the puncture needle tube.

The stress separation connecting piece is arranged between the protective cap and the hemostatic sealing plug on the opposite side of the traction wire, namely the traction wire and the stress separation connecting piece are arranged on two sides of the puncture needle tube. In the process that the needle handle pulls the protective cap backwards through the pulling wire, before the protective cap is not separated from the hemostatic sealing plug, the pulling wire can pull the protective cap to incline so that the tip of the puncture needle tube is not opposite to the needle tube sliding hole (the tip of the puncture needle tube is opposite to the inner wall of the protective cap), and when the pulling wire pulls the protective cap to be separated from the hemostatic sealing plug, the tip part of the puncture needle tube is inserted into the side wall of the protective cap. The protection effect is better. The traction wire is a flexible wire which can be bent, such as a twine, a cotton thread or a medical suture line. The elastic deformation amount of the flexible wire which is stretched by external force is smaller than 5%, and the elastic deformation amount of the flexible wire which is stretched by external force is preferably 0.5-2%. The flexible wire can be elastically retracted backwards after being elastically deformed, the front side wall of the protective cap positioned in front of the tip of the puncture needle tube can be pulled backwards, the tip of the puncture needle tube is made to puncture the front side wall of the protective cap, the stability is improved, and the protective effect is better.

According to the utility model, a needle handle 8 is further improved, a needle tube assembly hole is formed in the front side of the inner part of the installation cavity, a dispensing hole 18 in the shape of a reverse cone is formed in the front part of the needle tube assembly hole, and a radial glue storage hole 14 which is perpendicular to the needle tube assembly hole and communicated with the dispensing hole is formed in the needle handle on one side of the needle tube assembly hole in the rear part of the dispensing hole 18; a communication flow passage is arranged on the mounting cavity between the radial glue storage hole 14 and the glue dispensing hole 18, and the radial glue storage hole 14 radially penetrates through the side wall of the mounting cavity. The effect of uniformly distributing 2-3 radial glue storage holes 14 on the circumference of the needle tube assembly hole is better. The needle handle is provided with a needle tube assembly hole on the front side of the inner part of the installation cavity, the front part of the needle tube assembly hole is provided with a dispensing hole in a reverse cone shape, when the needle handle is assembled, kong Nadian glue is dispensed firstly, and after the puncture needle tube is inserted into the needle tube assembly hole from the dispensing hole, the glue is mainly accumulated at the dispensing hole. The connection firmness of the puncture needle tube and the needle handle is required to be technical, and the separation force of the puncture needle tube and the needle handle is not less than 30N, so that the needle tube is prevented from falling off in a human body when being pulled out after the puncture is completed; to ensure this separation force, the reverse taper of the cylindrical portion of the needle shaft must be sufficiently large and deep, i.e., axially long. From the condition of the current product drawing and separating experiment, the whole puncture needle tube is connected with glue together and is separated from the glue dispensing hole of the inverted cone. According to the radial glue storage hole, the dried glue is not easy to separate from the glue dispensing hole, the connection firmness of the puncture needle tube and the needle handle is improved, and the product drawing and separating experiment proves that the separation force of the puncture needle tube and the needle handle is above 50N and most of the dried glue is separated from the puncture needle tube due to the arrangement of the glue dispensing hole. This structure cooperates with the pulling force demand of protective cap, prevents to increase the protective cap structure after, will puncture needle tubing and pull out the unexpected emergence that in-process pulling force increased and led to needle handle and puncture needle tubing to separate.

The utility model relates to a preparation method of a needle tip shielding type indwelling needle, which comprises the following steps: in the assembly process, the front part of the needle following device is inserted into the rear end part of the sleeve, the front end of the sleeve is placed into the sleeve connecting hole from the opening at the rear end of the mounting cavity forwards through the mounting cavity, the needle following device is pressed forwards, and the front end of the needle following device is pressed into the sleeve connecting hole; the puncture needle tube is placed in the center of the hemostatic sealing plug from one side of the hemostatic sealing plug through the needle tube placement notch; the protective cap is sleeved on the puncture needle tube through the rear end of the puncture needle tube, and is connected with the hemostatic sealing plug through a force-separating connecting piece; the two ends of the traction wire are fixedly connected with the rear end of the protective cap and the needle handle respectively; the rear part of the puncture needle tube is inserted into a needle tube assembly hole of the needle handle and fixedly connected with the needle handle in a dispensing mode; the front end of the puncture needle tube is placed into the sleeve tube from the opening at the rear end of the installation cavity forwards through the installation cavity and the needle following device, the hemostatic sealing plug and the protective cap are extruded into the sleeve tube seat together, and the needle handle cover is arranged on the opening at the rear end of the installation cavity.

The preparation method of the needle tip shielding type indwelling needle comprises the following steps: in the assembly process, the front part of the needle following device is inserted into the rear end part of the sleeve, the front end of the sleeve is placed into the sleeve connecting hole from the opening at the rear end of the mounting cavity forwards through the mounting cavity, the needle following device is pressed forwards, and the front end of the needle following device is pressed into the sleeve connecting hole; the puncture needle tube is placed in the center of the hemostatic sealing plug from one side of the hemostatic sealing plug through the needle tube placement notch; the protective cap is sleeved on the puncture needle tube through the rear end of the puncture needle tube; the two ends of the traction wire are fixedly connected with the rear end of the protective cap and the needle handle respectively; the rear part of the puncture needle tube is inserted into a needle tube assembly hole of the needle handle and fixedly connected with the needle handle in a dispensing mode; the front end of the puncture needle tube is placed into the sleeve through the mounting cavity forwards and the needle following device from the opening at the rear end of the mounting cavity; the hemostatic sealing plug is extruded and installed into the sleeve seat, the protective cap is installed in the sleeve seat, and the needle handle cover is arranged on the opening at the rear end of the installation cavity.

Claims

1. A needle tip shielding type indwelling needle comprises a three-way joint, a connecting catheter, a cannula holder, a needle handle, a hemostatic sealing plug, a puncture needle tube, a needle following device, a cannula and a sheath, wherein the front end of the cannula holder is provided with a cannula connecting hole, an installation cavity with an open rear end is arranged in the cannula holder at the rear side of the cannula connecting hole, and the installation cavity is excessively connected with the cannula connecting hole through a horn-shaped needle following hole; the rear part of the sleeve is inserted into the sleeve connecting hole, the needle following device is in a funnel shape and is in interference fit with the needle following hole, the front part of the needle following device is inserted into the rear end part of the sleeve, the rear end part of the sleeve is extruded and fixed in the sleeve connecting hole, the puncture needle tube is arranged in the sleeve in a penetrating way, the front end of the sleeve is contracted and tightly attached to the puncture needle tube, the hemostatic sealing plug is arranged in the mounting cavity at the rear side of the needle following device, the puncture needle tube is sealed with the inner side of the mounting cavity, the needle handle cover is arranged at the rear end of the mounting cavity, and the rear end of the puncture needle tube is fixedly connected with the needle handle; an injection joint is arranged on a sleeve seat between the hemostatic sealing plug and the needle following device, a connecting catheter is communicated with the inside of the installation cavity through the injection joint, a three-way joint is arranged at the other end of the connecting catheter, and a heparin cap and a protective cap are arranged on the three-way joint; the hemostatic needle is characterized in that a protective cap is arranged in a mounting cavity between the hemostatic sealing plug and the needle handle, the protective cap can be sleeved on the puncture needle tube in an axial sliding manner along the puncture needle tube, a pull wire is arranged between the rear end of the protective cap and the needle handle, the length of the pull wire is smaller than that of the puncture needle tube at the front side of the needle handle, and the sum of the length of the pull wire and the thickness of the protective cap is not smaller than that of the puncture needle tube at the front side of the needle handle.

2. The needle tip shielding type indwelling needle according to claim 1, wherein said hemostatic plug is cylindrical, a needle tube insertion slot is provided on one side of the hemostatic plug, said needle tube is inserted into the center of the hemostatic plug from one side of the hemostatic plug through the needle tube insertion slot.

3. The needle tip shielding type indwelling needle according to claim 1 or 2, wherein said protecting cap is in the shape of a cap with an opening at the rear side, a needle tube sliding hole matched with the puncture needle tube is provided in the middle part of the front side wall of the protecting cap, and the puncture needle tube can freely slide back and forth through the needle tube sliding hole.

4. The needle tip shielding type indwelling needle according to claim 1, wherein the protecting cap is in contact with the inner wall of the installation cavity, and the friction force between the protecting cap and the inner wall of the installation cavity is 0.1-10N.

5. The needle tip shielding type indwelling needle according to claim 1, wherein a force-bearing disengaging connector is arranged between the front end of the protecting cap and the rear end of the hemostatic sealing plug, and when the force-bearing disengaging connector is subjected to a tensile force exceeding the connecting force, the protecting cap is separated from the hemostatic sealing plug; the connection force is 0.1-10N.

6. The needle tip shielding type indwelling needle according to claim 5, wherein said force-bearing disengaging connector is provided with a plug-in connecting post on one side of the front end of the protecting cap, a plug-in hole matched with the plug-in connecting post is provided on the rear end of the hemostatic sealing plug, and the plug-in connecting post is inserted into the plug-in hole in interference fit.

7. The needle tip shielding type indwelling needle according to claim 6, wherein a pulling wire is arranged between one side of the rear end of the protecting cap and the same side of the needle handle, and the stress disengaging connector is arranged between the protecting cap and the hemostatic sealing plug on the side opposite to the pulling wire.

8. The needle tip shielding type indwelling needle according to claim 4, wherein a traction wire is arranged between one side of the rear end of the protective cap and the same side of the needle handle, an auxiliary wire is arranged between the rear end of the protective cap and the opposite side of the traction wire and the needle handle, and the length of the auxiliary wire is 0.3-3 mm greater than that of the traction wire.

9. The needle tip shielding type indwelling needle according to claim 1, wherein a needle tube assembly hole is formed in the front side of the needle handle, a dispensing hole in the shape of a reverse cone is formed in the front of the needle tube assembly hole, and a radial glue storage hole is formed in the needle handle on one side of the needle tube assembly hole.