Biopsy forceps with integrated forceps head and manufacturing method thereof

Abstract

The invention discloses a biopsy forceps with an integrated forceps head and a manufacturing method thereof. The integrated forceps head comprises an integrally formed left forceps head, a right forceps head and a forceps handle for connecting the left forceps head and the right forceps head, the forceps handle is folded in half, and a center hole is provided in the middle of the forceps handle; the left forceps head and the right forceps head provided at both ends of the forceps handle are elastic and are shaped to be in an initial state of opening in opposite directions. The integrated forceps head, a pull rod pin and a pull rod tube are assembled into a forceps head kit; the forceps head kit, a pull rod positioning block and a forceps head seat are assembled into a forceps head assembly; and the forceps head assembly, a pull cable, a spring tube and a control handle are assembled into the entire biopsy forceps; the structure and assembly process of the biopsy forceps are simplified.

Description

Technical Field

[0001] The invention relates to a biopsy forceps, in particular to a biopsy forceps with an integrated forceps head, and also to a manufacturing method of the biopsy forceps. Background Art

[0002] Biopsy forceps is a tool used to bite and sample the lesion in the abdominal cavity of the human body, and is generally used in conjunction with an endoscope. During endoscopic examination, when a pathological examination of the lesion is required, the biopsy forceps is inserted into the patient's body through the endoscope forceps channel to clamp the tissue of the lesion. Sampling with biopsy forceps is less painful and less traumatic, so it is very popular among doctors and patients.

[0003] Biopsy forceps generally consist of a clamp head assembly, a slender cable, a spring tube that is also slender and sleeved outside the cable, and a handle. One end of the cable is connected to the four-bar linkage in the clamp head assembly, and the other end is connected to the movable handle on the handle. One end of the spring tube is connected to the clamp head assembly, and the other end is connected to the handle. Pushing and pulling the movable handle drives the cable, and the cable drives the four-bar linkage to move. The four-bar linkage drives the two symmetrically arranged clamp heads on the clamp head assembly to open and close, thereby removing suspicious tissue from the body.

[0004] In the existing biopsy forceps head assembly, two independent forceps heads are connected to the forceps head bracket by rivets, and the two independent forceps heads are pushed and pulled by a four-bar linkage to realize the opening and closing control of the forceps heads. This forceps head assembly has a complex structure, a complex process during assembly, and is difficult to assemble. Summary of the invention

[0005] The primary technical problem to be solved by the present invention is to provide a biopsy forceps with an integrated forceps head.

[0006] Another technical problem to be solved by the present invention is to provide a method for manufacturing the biopsy forceps.

[0007] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0008] According to a first aspect of an embodiment of the present invention, a biopsy forceps with an integrated forceps head is provided, wherein the integrated forceps head includes an integrally formed left forceps head, a right forceps head and a forceps handle for connecting the left forceps head and the right forceps head, the forceps handle is folded in half, and a center hole is provided in the middle of the forceps handle; the left forceps head and the right forceps head arranged at both ends of the forceps handle are elastic and are formed into an initial state of being opened in opposite directions.

[0009] Preferably, the biopsy forceps also include a pull rod pin and a pull rod tube; the front end of the pull rod pin is stuck in front of the center hole, and the rear end of the pull rod pin is inserted into the center hole and connected and fixed with the pull rod tube to form a forceps head kit.

[0010] Preferably, the pull rod pin is a T-shaped flat-head pull rod pin.

[0011] Alternatively, preferably, the pull rod pin is a needle tip pull rod pin with a sampling needle portion at the front end; the rear end of the needle tip pull rod pin passes through the center hole and is plugged and fixed to the pull rod tube; the sampling needle portion extends forward in the sample storage groove between the left clamp head and the right clamp head. A protrusion protruding outward is formed at the front end of the sampling needle portion.

[0012] Preferably, the biopsy forceps further comprises a forceps head seat and a pull rod positioning block; wherein the forceps head seat is a sleeve having blind holes at both ends and a plugging arrangement in the middle, and a connecting hole penetrating the two blind hole areas is arranged in the plugging arrangement;

[0013] The tie rod positioning block is a round tube fixed on the outer wall of the tie rod tube;

[0014] The pull rod tube in the pliers head kit extends backward through the connecting hole, and the left pliers head and the right pliers head are confined in the blind hole at the front end of the pliers head seat; the pull rod positioning block is confined in the blind hole at the rear end of the pliers head seat, which is used to limit the maximum distance that the pliers head kit can be pushed forward.

[0015] According to a second aspect of an embodiment of the present invention, a method for manufacturing the above-mentioned biopsy forceps is provided, comprising the following steps of manufacturing an integrated forceps head:

[0016] (1) Punching out the outer contour of the integrated clamp head, and punching out two pressure relief holes located at the position of the clamp head and a center hole located at the center position;

[0017] (2) obtaining two spoon cups at both ends of the one-piece pliers head by stamping and stretching;

[0018] (3) folding out the overall shape of the integrated clamp head by stamping;

[0019] (4) The hardness and mechanical strength of the integrated pliers head are obtained through heat treatment.

[0020] Preferably, the method further comprises the following steps of assembling the pliers head kit: after the pull rod pin is passed through the central hole of the integrated pliers head, it is plugged into and fixed with the pull rod tube to form the pliers head kit.

[0021] Preferably, when assembling the needleless biopsy forceps, the pull rod pin used is a T-shaped flat-head pull rod pin; when assembling the needle biopsy forceps, the pull rod pin used is a needle tip pull rod pin with a sampling needle portion at the front end.

[0022] Preferably, the step of assembling the pliers head assembly is further included: the pliers head kit is installed into the pliers head seat, and the integrated pliers head is confined in the blind hole area at the front end of the pliers head seat; the pull rod tube is inserted into the blind hole area at the rear end of the pliers head seat after passing through the connecting hole, and a pull rod positioning block is provided on the outer wall of the rear end of the pull rod tube to limit the maximum distance that the pliers head kit can be pushed forward.

[0023] The present invention provides a biopsy forceps with an integrated forceps head, wherein the integrated forceps head includes an integrally formed left forceps head, a right forceps head, and a forceps handle for connecting the left forceps head and the right forceps head. The structure and assembly process of the biopsy forceps are simplified by assembling the integrated forceps head, a pull rod pin, and a pull rod tube into a forceps head kit; assembling the forceps head kit, a pull rod positioning block, and a forceps head seat into a forceps head assembly; and then assembling the forceps head assembly, a pull cable, a spring tube, and a control handle into the entire biopsy forceps. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of the forceps head assembly of the first biopsy forceps provided by the present invention;

[0025] Figure 2 It is a structural schematic diagram of the forceps head assembly of the second biopsy forceps provided by the present invention;

[0026] Figure 3A and Figure 3B They are respectively a front view schematic diagram and a top view schematic diagram of the outline of the one-piece biopsy forceps punched out;

[0027] Figure 4A and Figure 4B They are respectively a front view schematic diagram and a top view schematic diagram of a spoon cup with an integrated clamp head punched out;

[0028] Figure 5A and Figure 5B They are respectively a front view schematic diagram and a side view schematic diagram of a finished one-piece clamp head;

[0029] Fig. 6A and Figure 6B They are respectively a front view schematic diagram and a side view schematic diagram of a flat head tie rod pin;

[0030] Figure 7 It is a schematic diagram of the structure of the needle tip pull rod pin;

[0031] Fig. 8A and Figure 8B They are the front view schematic diagram and the side view schematic diagram of the tie rod tube respectively;

[0032] Fig. 9 is a schematic diagram of the structure of the assembled clamp head kit;

[0033] Fig.10 It is a structural schematic diagram of the clamp head seat;

[0034] Fig.11 It is a structural schematic diagram of the pull rod positioning block. DETAILED DESCRIPTION

[0035] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0036] In order to simplify the structure and manufacturing process of biopsy forceps, the present invention provides biopsy forceps with an integrated forceps head. The following is an introduction taking needleless biopsy forceps and needled biopsy forceps as examples.

[0037] First embodiment

[0038] like Figure 1 As shown, the needleless biopsy forceps with an integrated forceps head include an integrated forceps head 1, a flat-head pull rod pin 2, a pull rod tube 3, a pull rod positioning block 4 and a forceps head seat 10, wherein the integrated forceps head 1, the flat-head pull rod pin 2 and the pull rod tube 3 constitute a forceps head kit, and the forceps head kit, the forceps head seat 10 and the pull rod positioning block 4 are assembled to form a forceps head assembly.

[0039] Specifically, the structure of the integrated clamp head 1 is as follows: Figure 5A and 5B As shown, it includes an integrally formed left pliers head 1a, a right pliers head 1b and a pliers handle 1c for connecting the left pliers head 1a and the right pliers head 1b. The integral pliers head is integrally formed by a stamping process from a stainless steel material. The pliers handle 1c is folded in half, and a center hole 1d is provided in the middle of the pliers handle 1c (see Figure 3B and Figure 4B The left clamp head 1a and the right clamp head 1b disposed at both ends of the clamp handle 1c are elastic and are shaped to be in an initial state of being naturally opened to opposite sides; pressure relief holes 1e are formed in the left clamp head 1a and the right clamp head 1b, respectively.

[0040] like Fig. 6A and Figure 6B The flat-head pull rod pin 2 shown is a T-shaped pull rod pin with a larger front and a smaller rear. The diameter of the head of the flat-head pull rod pin 2 is larger than the diameter of the center hole 1d. The diameter of the cylinder at the rear of the flat-head pull rod pin 2 is equal to or smaller than the diameter of the center hole 1d and is roughly equal to the inner diameter of the pull rod tube 3. The front end of the flat-head pull rod pin 2 is stuck in front of the center hole 1d. After the cylinder at the rear of the flat-head pull rod pin 2 is inserted into the center hole 1d of the integrated clamp head 1, it is Fig. 8A and Figure 8B The pull rod tube 3 shown is plugged and fixed to form a clamp head kit. The structure of the clamp head kit is as shown in FIG. Fig. 9 shown.

[0041] like Fig. 8A and Figure 8B The pull rod tube 3 shown is a section of a round tube. Fig.11The tie rod positioning block 4 shown is another section of a circular tube; the inner diameter of the tie rod positioning block 4 is equal to the outer diameter of the tie rod tube 3 .

[0042] like Fig.10 The clamp head seat 10 shown is a sleeve with blind holes at both ends and a plug in the middle, and a connecting hole 13 penetrating the two blind hole areas 11 and 12 is provided in the plug.

[0043] like Figure 1 As shown, the pliers head set is assembled inside the pliers head seat 10 to form a pliers head assembly. The rod tube 3 in the pliers head set extends backward through the connecting hole 13, and the left pliers head 1a and the right pliers head 1b are restricted in the blind hole 11 at the front end of the pliers head seat 10; the rod positioning block 4 is a round tube fixed on the outer wall of the rod tube 3, and the rod positioning block 4 is restricted in the blind hole 12 at the rear end of the pliers head seat 10, which is used to limit the maximum distance that the pliers head set can be pushed forward.

[0044] The clamp head assembly is subjected to the same processes as the current biopsy forceps assembly process, such as cable docking, spring tube welding, and handle assembly, to obtain a complete biopsy forceps.

[0045] use Figure 1 After the shown forceps head assembly is assembled into a biopsy forceps, when the pull rod tube 3 is pulled downward by the action of the cable, the integrated forceps head 1 moves downward toward the forceps head seat 10. Since the side walls of the left forceps head 1a and the right forceps head 1b are in contact with the forceps head seat 10, the forceps heads are squeezed and forced to close, thereby realizing the closing function of the forceps heads; when the pull rod tube 3 is pushed to move upward, the integrated forceps head 1 extends out from the forceps head seat, and with the help of the elastic characteristics of the forceps heads themselves, the left forceps head 1a and the right forceps head 1b open.

[0046] In this embodiment, the integrated clamp head, the flat head pull rod pin and the pull rod tube are assembled together to obtain a clamp head kit, and the clamp head kit, the pull rod positioning block and the clamp head seat are assembled together to obtain a clamp head assembly. Compared with the clamp head assembly with a four-bar structure, the above clamp head assembly has a simple structure, low cost and convenient assembly. In addition to eliminating the parts of the four-bar connection, the above biopsy forceps also simplifies the assembly process such as rivet welding, greatly improving the production and processing efficiency.

[0047] In addition, since the forceps head used in the biopsy forceps is an integrated forceps head obtained by a stamping process, the assembly accuracy is high, which can effectively improve the fit of the forceps head assembly and reduce the bleeding problem caused by sampling.

[0048] Second embodiment

[0049] like Figure 2As shown, a needle biopsy forceps with an integrated forceps head includes an integrated forceps head 1, a needle tip pull rod pin 5, a pull rod tube 3, a pull rod positioning block 4 and a forceps head seat 10, wherein the integrated forceps head 1, the needle tip pull rod pin 5 and the pull rod tube 3 constitute a forceps head kit, and the forceps head kit, the forceps head seat 10 and the pull rod positioning block 4 are assembled to form a forceps head assembly.

[0050] Among them, in the forceps head kit, except that the needle tip pull rod pin 5 is different from the flat head pull rod pin 2 used in the first embodiment, the rest of the structure is the same as the structure of the needleless biopsy forceps provided in the first embodiment. In the needle biopsy forceps provided in this embodiment, Figure 7 The needle tip pull rod pin 5 shown is a pull rod pin with a sampling needle portion 5a at the front end, and a protrusion 5c protruding outward is provided at the front end of the sampling needle portion 5a. The sampling needle portion 5a extends forward in the sample storage groove between the left clamp head 1a and the right clamp head 1b, and the rear end 5b of the needle tip pull rod pin 5 passes through the central hole 1d of the integrated clamp head 1 and is plugged and fixed with the pull rod tube 3 to form a clamp head kit.

[0051] In this embodiment, the process of assembling the forceps head kit, the forceps head seat 10 and the pull rod positioning block 4 into the forceps head assembly, and the process of assembling the forceps head assembly and other parts into the biopsy forceps are the same as those in the first embodiment and will not be repeated here.

[0052] In the needle biopsy forceps, a long strip sample storage slot is provided in the forceps head seat 10. By pulling the integrated forceps head 1 backward or pushing the integrated forceps head 1 forward, the integrated forceps head 1 can be opened and closed multiple times continuously to complete multiple continuous sampling; the sample tissues obtained by multiple samplings are sequentially stored on the sampling needle portion 5a between the left forceps head 1a and the right forceps head 1b. During the multiple opening and closing of the disposable forceps head 1, the protrusion 5c provided at the front end of the sampling needle portion 5a can prevent the sample tissue stored on the sampling needle portion 5a from falling off.

[0053] The needle biopsy forceps provided in this embodiment also has the advantages of simple structure, low cost and convenient assembly. In addition to eliminating the parts of the four-link, the above structure also simplifies the assembly process such as rivet welding, greatly improving the production and processing efficiency.

[0054] Likewise, since the forceps head used in the biopsy forceps is an integrated forceps head obtained by a stamping process, the assembly accuracy is high, which can effectively improve the fit of the forceps head assembly and reduce the bleeding problem caused by sampling.

[0055] Third embodiment

[0056] The structures of the two biopsy forceps are introduced in detail above, and the corresponding manufacturing methods are introduced below.

[0057] The present invention also provides a method for manufacturing a biopsy forceps with an integrated forceps head, comprising the following steps: manufacturing an integrated forceps head; assembling the integrated forceps head, a pull rod pin, and a pull rod tube into a forceps head kit; assembling the forceps head kit, a forceps head seat, and a pull rod positioning block into a forceps head assembly; and assembling the forceps head assembly, a pull cable, a spring tube, and a control handle into a biopsy forceps. The material used for the entire forceps head assembly can be a stainless steel material that meets medical standards, for example, 2Cr13, 3Cr13, and other materials that meet the standard requirements of biopsy forceps are used.

[0058] Specifically, firstly, the integrated pliers head 1 is manufactured by adopting a stamping process.

[0059] The manufacturing steps of the integrated clamp head 1 are as follows:

[0060] (1) Figure 3A and Figure 3B As shown, the outer contour of the integrated clamp head 1 is punched out, and two pressure relief holes 1e located at the clamp head position and a center hole 1d set at the center position are punched out;

[0061] (2) Figure 4A and Figure 4B As shown, two spoon cups (i.e., the left tongs head 1a and the right tongs head 1b) are obtained at both ends of the one-piece tongs head 1 by stamping and stretching;

[0062] (3) Figure 5A and 5B As shown, the overall shape of the integrated clamp head 1 is folded out by stamping;

[0063] (4) The hardness and mechanical strength of the integrated pliers head 1 are obtained through heat treatment.

[0064] Since the forceps head used in the biopsy forceps provided by the present invention is an integrated forceps head obtained by stamping and forming technology, the assembly accuracy is high, which can effectively improve the fit of the forceps head assembly and reduce the bleeding problem caused by sampling.

[0065] Secondly, the integrated pliers head 1, the pull rod pin (the flat-head pull rod pin 2 or the needle-point pull rod pin 5), and the pull rod tube are assembled together to form a pliers head kit.

[0066] The steps of assembling the pliers head set are as follows: after the pull rod pin (flat pull rod pin 2 or needle tip pull rod pin 5) is passed through the central hole 1d of the integrated pliers head 1, it is plugged and fixed with the pull rod tube 3, thereby completing the assembly of the pliers head set. Specifically, the pull rod pin and the pull rod tube 3 can be welded into one by laser welding.

[0067] When assembling the needleless biopsy forceps, the pull rod pin used is as follows Fig. 6A and Figure 6BThe flat head pull rod pin 2 shown in the T-shape; when assembled with the needle biopsy forceps, the pull rod pin used is as shown in the Figure 7 The front end of the needle tip pull rod pin 5 is shown to have a sampling needle portion 5a. Both the flat head pull rod pin 2 and the needle tip pull rod pin 5 can be obtained by machining.

[0068] Third, the pliers head assembly is formed by assembling the pliers head kit, the pliers head seat 10 and the pull rod positioning block together.

[0069] like Fig. 8A and Figure 8B As shown, a section of stainless steel pipe can be cut out by wire cutting as the tie rod pipe 3. Fig.11 The tie rod positioning block 4 shown is another section of a circular tube; the inner diameter of the tie rod positioning block 4 is almost equal to the outer diameter of the tie rod tube 3 .

[0070] like Fig.10 The clamp head seat 10 shown is a sleeve with blind holes at both ends and a plug in the middle, and a connecting hole 13 penetrating the two blind hole areas 11 and 12 is provided in the plug.

[0071] To assemble the pliers head assembly: Install the pliers head assembly into Fig.10 In the clamp head seat 10 shown in the figure, the integrated clamp head 1 is confined in the blind hole area 11 at the front end of the clamp head seat 10; the tie rod tube 3 is inserted into the blind hole area 12 at the rear end of the clamp head seat 10 after passing through the connecting hole 13; then the tie rod positioning block 4 is set on the outer wall of the tie rod tube 3, and after determining the position of the tie rod positioning block 4, the tie rod positioning block 4 and the tie rod tube 3 are welded into one body by laser welding to obtain the clamp head assembly. The function of the tie rod positioning block 4 is to limit the maximum distance that the clamp head kit can be pushed forward. The position of the tie rod positioning block 4 must ensure that when the tie rod positioning block 4 is pushed to the blocking part of the clamp head seat 10, the integrated clamp head 1 will not be pushed out of the clamp head seat 10.

[0072] Finally, the clamp head assembly is subjected to the same processes as the current biopsy forceps assembly process, such as cable docking, spring tube welding, and handle assembly, to obtain a complete biopsy forceps.

[0073] After the forceps head assembly is used to assemble the biopsy forceps, when the pull rod tube is pulled downward by the action of the pull cable, the integrated forceps head 1 moves downward toward the forceps head seat 10. Since the side walls of the left forceps head 1a and the right forceps head 1b are in contact with the forceps head seat 10, the two forceps heads of the integrated forceps head 1 are squeezed and forced to close, thereby realizing the closing function of the forceps heads; when the pull rod tube is pushed upward, the left forceps head 1a and the right forceps head 1b are respectively extended from the forceps head seat 10, and the elastic characteristics of the integrated forceps head 1 are used to realize the opening function of the forceps heads.

[0074] The present invention provides a novel biopsy forceps, wherein the forceps head assembly is composed of an integrated forceps head 1, a needle-tip pull rod pin 5 or a flat-head pull rod pin 2, a pull rod tube 3, a pull rod positioning block 4 and a forceps head seat 10. The invention has the advantages of simple assembly and low cost. Compared with various types of forceps head assemblies currently used, the connecting rod parts are omitted, the assembly process such as rivet welding is simplified, and the production and processing efficiency is greatly improved.

[0075] In summary, the biopsy forceps with an integrated forceps head provided by the present invention are assembled into a forceps head kit by combining an integrated forceps head, a pull rod pin, and a pull rod tube; and the forceps head kit, a pull rod positioning block, and a forceps head seat are assembled into a forceps head assembly; and the forceps head assembly, a pull cable, a spring tube, and a control handle are assembled into the entire biopsy forceps; thereby simplifying the structure and assembly process of the biopsy forceps.

[0076] The above is a detailed description of the biopsy forceps with an integrated forceps head and the manufacturing method thereof provided by the present invention. For those skilled in the art, any obvious changes made to it without departing from the essential spirit of the present invention will constitute an infringement of the patent right of the present invention and will bear corresponding legal liabilities.

Claims

1. A biopsy forceps with an integrated forceps head, characterized in that The invention comprises an integrated pliers head, wherein the integrated pliers head comprises an integrally formed left pliers head, a right pliers head and a pliers handle for connecting the left pliers head and the right pliers head, wherein the pliers handle is folded in half and a central hole is provided in the middle of the pliers handle; the left pliers head and the right pliers head provided at both ends of the pliers handle are elastic and are formed to be in an initial state of opening in opposite directions; The biopsy forceps also include a needle tip pull rod pin and a pull rod tube with a sampling needle portion at the front end; wherein the outer diameter of the front end of the needle tip pull rod pin is larger than the aperture of the center hole, and the outer diameter of the rear end of the needle tip pull rod pin is smaller than the aperture of the center hole; the inner diameter of the pull rod tube matches the outer diameter of the rear end of the pull rod pin, and the outer diameter of the pull rod tube is larger than the aperture of the center hole; The rear end of the needle tip pull rod pin passes through the central hole and is plugged and fixed with the pull rod tube to form a clamp head kit; the sampling needle portion extends forward in the sample storage groove between the left clamp head and the right clamp head, and a protrusion protruding outward is formed at the front end of the sampling needle portion; The integrated clamp head is pulled or pushed to open and close the integrated clamp head for multiple times in succession, and drives the sampling needle to move synchronously, so that the sample tissues obtained by multiple samplings are sequentially stored on the sampling needle.

2. The biopsy forceps according to claim 1, characterized in that It also includes a clamp head seat and a pull rod positioning block; wherein the clamp head seat is a sleeve with blind holes at both ends and a plug in the middle, and a connecting hole penetrating the two blind hole areas is provided in the plug; The pull rod tube in the pliers head kit extends backward through the connecting hole, and the left pliers head and the right pliers head are confined in the blind hole at the front end of the pliers head seat; the pull rod positioning block is a round tube fixed on the outer wall of the pull rod tube, and the pull rod positioning block is confined in the blind hole at the rear end of the pliers head seat, and is used to limit the maximum position of the pliers head kit pushed forward.

3. A method for manufacturing a biopsy forceps with an integrated forceps head, characterized in that The method comprises the following steps of manufacturing an integrated pliers head: (1) Punching out the outer contour of the integrated pliers head, and punching out two pressure relief holes and a center hole at the center of the pliers head; (2) obtaining two spoon cups at both ends of the one-piece pliers head by stamping and stretching; (3) folding out the overall shape of the integrated clamp head by stamping; (4) obtaining the hardness and mechanical strength of the integrated clamp head through heat treatment; Also included are the following steps to assemble the pliers head kit: After a needle tip pull rod pin with a sampling needle portion at the front end is passed through the center hole, it is plugged and fixed with the pull rod tube to form a pliers head kit; wherein, the outer diameter of the front end of the needle tip pull rod pin is larger than the aperture of the center hole, and the outer diameter of the rear end of the needle tip pull rod pin is smaller than the aperture of the center hole; the inner diameter of the pull rod tube matches the outer diameter of the rear end of the needle tip pull rod pin, and the outer diameter of the pull rod tube is larger than the aperture of the center hole, and a protrusion protruding outward is formed at the front end of the sampling needle portion.

4. The manufacturing method according to claim 3, characterized in that It also includes the following steps of assembling the pliers head assembly: installing the pliers head kit into the pliers head seat, and the integrated pliers head is confined to the blind hole area at the front end of the pliers head seat; the pull rod tube passes through the connecting hole and is inserted into the blind hole area at the rear end of the pliers head seat, and a pull rod positioning block is provided on the outer wall at the rear end of the pull rod tube to limit the maximum distance that the pliers head kit can be pushed forward.

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