Linear cutting anastomat with movable handle self-locking function

Abstract

The utility model discloses a linear type cutting anastomat with a movable handle self-locking function, which comprises a lower jaw component and an upper jaw component, the middle parts of the lower jaw component and the upper jaw component are rotatably hung together, the left end of the lower jaw component is provided with a nail propping seat component, and the right end of the lower jaw component is provided with a fixed handle; the left end of the upper jaw assembly is provided with a nail bin assembly, the right end of the upper jaw assembly is provided with an upper jaw framework, the middle of the upper jaw assembly is hinged to a movable handle obliquely extending to be located above the upper jaw framework, the top of the upper jaw framework is provided with a clamping hook assembly extending upwards, and in the closed locking state, the movable handle, the upper jaw framework and the fixed handle are closed and attached together. The clamping hook assembly and the movable handle are buckled, locked and connected together; in the unlocking state, the clamping hook assembly is separated from the movable handle, and the movable handle obliquely extends to be located above the upper jaw framework. During use, the clamping hook assembly and the movable handle are buckled, locked and connected together, separation of the movable handle and the upper jaw framework in the cutting and suturing process is effectively eradicated, and stability and safety are both good.

Description

Technical Field

[0001] This utility model relates to the field of medical device technology, specifically to a linear cutting stapler with a self-locking function for a movable handle. Background Technology

[0002] Currently, manual linear cutting staplers are widely used in open surgeries involving the transection, resection, and suturing of respiratory and digestive tract tissues such as the lungs, stomach, and intestines. Manual linear cutting staplers generally have an upper jaw assembly and a lower jaw assembly. The front ends of the upper jaw assembly and the lower jaw assembly form human tissue clamping, cutting, and suturing jaws. The front end of the upper jaw assembly has a staple cartridge assembly inside. The middle part of the upper jaw assembly has a human tissue clamping movable handle. The middle part of the upper jaw assembly and the middle part of the lower jaw assembly have a rotating hook component between the upper and lower jaws. The tail of the upper jaw assembly also has a cutting and suturing firing device.

[0003] Existing manual linear cutting staplers lack a self-locking mechanism for their tissue-holding handles. This can lead to separation between the handle and the upper jaw assembly during surgery, potentially causing the held tissue to detach from the jaws and increasing surgical risks. Therefore, this invention proposes a linear cutting stapler with a self-locking handle to address these technical problems. Summary of the Invention

[0004] The purpose of this invention is to overcome the defects in the existing technology and provide a linear cutting stapler with a self-locking movable handle. In use, the clamping cutting and suturing jaws between the upper jaw assembly (upper staple cartridge assembly) and the lower jaw assembly (upper staple seat assembly) hold the tissue to be cut and sutured. Then, the upper and lower jaw assemblies are rotatably connected together via a rotating hook assembly. Subsequently, the movable handle is pressed against the upper jaw skeleton and the fixed handle until it is flush with the upper jaw skeleton. At this point, the hook assembly on the upper jaw skeleton engages and locks with the movable handle, changing the linear cutting stapler from an unlocked state to a closed and locked state. This effectively prevents the movable handle from separating from the upper jaw skeleton during the cutting and suturing process, ensuring the stability and safety of the linear cutting stapler during surgical procedures. The overall structural design is ingenious and reasonable, with high feasibility for fabrication and implementation, and strong practicality.

[0005] To achieve the above objectives, the technical solution of this utility model is to design a linear cutting stapler with a self-locking movable handle, including a lower jaw assembly and an upper jaw assembly. The upper jaw assembly and the lower jaw assembly have rotating hooking components in their middle sections to allow them to rotate and connect together. The lower jaw assembly has a staple seat assembly at its left end and a fixed handle at its right end. The upper jaw assembly has a staple cartridge assembly at its left end, an upper jaw frame at its right end, and a movable handle that extends obliquely and is located above the upper jaw frame, hinged in the middle. The upper jaw frame has an upwardly extending hook assembly at its top. The linear cutting stapler has a closed and locked state and an unlocked state. In the closed and locked state, the movable handle, the upper jaw frame, and the fixed handle are closed and tightly fitted together, and the hook assembly is locked and connected to the movable handle. In the unlocked state, the hook assembly is disengaged from the movable handle, and the movable handle extends obliquely and is located above the upper jaw frame.

[0006] This utility model discloses a linear cutting stapler with a self-locking movable handle. In use, the clamping cutting and suturing jaws between the upper jaw assembly (upper staple cartridge) and the lower jaw assembly (upper staple seat) hold the tissue to be cut and sutured. Then, the upper and lower jaw assemblies are rotatably connected together via a rotating hook assembly. Next, the movable handle is pressed against the upper jaw skeleton and the fixed handle until it is flush with the upper jaw skeleton. At this point, the hook assembly on the upper jaw skeleton engages and locks with the movable handle, changing the linear cutting stapler from an unlocked state to a closed and locked state. This effectively prevents the movable handle from separating from the upper jaw skeleton during cutting and suturing, ensuring the stability and safety of the linear cutting stapler during surgical procedures. The overall structure is ingeniously and rationally designed, highly feasible to manufacture and implement, and highly practical.

[0007] The preferred technical solution is that the hook assembly includes a pin, a hook body, an arc-shaped reset spring, and a reset button. The pin is rotatably mounted on the front and rear side walls of the upper jaw frame. The connecting arm located at the lower end of the hook body is fixedly mounted on the middle of the pin. The hook body moves out from the inside of a hole at the top of the upper jaw frame and faces to the left, with the top of the hook body having a sloping structure that gradually extends downward from right to left. One end of the arc-shaped reset spring is inserted and fixed inside the right side of the connecting arm, and the other end extends out from the right end of the hole and overlaps and is fixed to the top of the upper jaw frame, with the concave arc side of the arc-shaped reset spring facing downward. The reset button is fixed to the end of the pin that extends out and is located outside the upper jaw frame. In the closed and locked state, the hook body is engaged with the top right end of the movable handle. The hook assembly has a clever and reasonable structural design, is easy to process and implement on a linear cutting stapler, and is highly feasible, ensuring the smooth preparation and implementation of the linear cutting stapler of this utility model.

[0008] A further preferred technical solution is that the reset button is located on the front outer side of the upper jaw frame, and a suture advance button is provided on the rear outer side of the upper jaw frame. The reset button and suture advance button are located on the front and rear sides of the upper jaw frame, effectively eliminating the potential for misoperation by medical personnel. Furthermore, their distribution conforms to ergonomic principles, ensuring the ease of use of the linear cutting stapler during surgical procedures.

[0009] A further preferred technical solution includes a nail box washer inside the upper jaw frame. The nail box washer has a U-shaped cross-section with the opening facing upwards, and the two ends of the pin are rotatably connected to the front and rear side walls of the nail box washer. This ensures the stability of the pin on the hook assembly on the upper jaw frame.

[0010] A further preferred technical solution includes a handle frame and a handle shell. The top of the handle frame has a second mounting hole and a locking hole at the right end. The top of the handle shell has a screw post extending downwards and a buckle extending downwards. The right end of the lower side of the top of the handle shell also has baffles on the front and rear sides and a notch between the two baffles. The handle shell is correspondingly fastened to the top of the handle frame. The two are fixedly connected by screws passing through the corresponding second mounting hole and the screw post. The buckle is inserted and fastened into the locking hole. The right end of the handle frame is located to the left of the two baffles. The top of the upper jaw frame also has a second channel for avoiding the lower end of the buckle. In the closed and locked state, the hook passes through the notch and engages with the top right end of the handle frame. The movable handle has a clever and reasonable structural design, in which the handle frame provides rigid support and the handle shell improves the grip comfort during use.

[0011] A further preferred technical solution is that a tail end shell is also installed at the right end of the upper jaw skeleton. In the closed and locked state, the tail end shell mates with the handle shell, further ensuring the grip comfort of the linear cutting stapler of this utility model during surgical operations.

[0012] A further preferred technical solution is that the lower jaw assembly has a pivot extending outward to the front and rear sides in the middle, and the upper jaw assembly is rotatably hooked to both ends of the pivot in the middle of the lower jaw assembly through a slot located in the middle of the front and rear side walls and opening downward. The pivot and the slot constitute the rotating hook assembly.

[0013] The upper left side of the front and rear side walls of the handle frame is provided with a mounting hole 1, and the lower left side of the front and rear side walls of the handle frame is provided with a hook groove with an opening facing the left. The left end of the handle frame is hinged to the upper middle part of the upper jaw assembly through a pivot 2 that passes through the mounting holes 1 on the front and rear sides. In the unlocked state, the hook grooves on the front and rear sides of the left end of the handle frame are engaged with the two ends of the pivot 1.

[0014] The advantages and beneficial effects of this utility model are as follows:

[0015] 1. This utility model discloses a linear cutting stapler with a self-locking movable handle. In use, the clamping cutting and suturing jaws between the upper jaw assembly (upper staple cartridge) and the lower jaw assembly (upper staple seat) hold the tissue to be cut and sutured. Then, the upper and lower jaw assemblies are rotatably connected together via a rotating hook assembly. Subsequently, the movable handle is pressed against the upper jaw skeleton and the fixed handle until it adheres to the upper jaw skeleton. At this point, the hook assembly on the upper jaw skeleton engages and locks with the movable handle, changing the linear cutting stapler from an unlocked state to a closed and locked state. This effectively prevents the movable handle from separating from the upper jaw skeleton during cutting and suturing, ensuring the stability and safety of the linear cutting stapler during surgical procedures. The overall structure is ingeniously and rationally designed, highly feasible to manufacture and implement, and highly practical.

[0016] 2. The hook assembly has a clever and reasonable structural design, which makes it easy to process and implement on a linear cutting stapler, and is highly feasible, ensuring that the linear cutting stapler of this utility model can be successfully prepared and implemented.

[0017] 3. The reset button is located on the front outer side of the upper jaw frame, and the suture advance button is located on the rear outer side of the upper jaw frame. The reset button and the suture advance button are located on the front and rear sides of the upper jaw frame, effectively eliminating the risk of misoperation by medical personnel. Furthermore, their distribution conforms to ergonomic principles, ensuring the ease of use of the linear cutting stapler of this utility model during surgical operations.

[0018] 4. The active handle has a clever and reasonable structural design. The handle frame provides rigid support, while the handle shell improves the grip comfort when using the active handle.

[0019] 5. A tail end shell is also installed at the right end of the upper jaw skeleton. In the closed and locked state, the tail end shell mates with the handle shell, further ensuring the grip comfort of the linear cutting stapler of this utility model during surgical operation. Attached Figure Description

[0020] Figure 1 This is a front view (unlocked state) of the linear cutting stapler with a self-locking function of the movable handle according to this utility model;

[0021] Figure 2 This is the front right view of the hook component;

[0022] Figure 3 This is the front left view of the hook component;

[0023] Figure 4 This is a partial view of the right end of the linear cutting stapler with a self-locking function of the movable handle according to this utility model;

[0024] Figure 5 This is a partial view of the right end of the linear cutting stapler with a self-locking function of the movable handle of this utility model (the upper jaw skeleton is hidden);

[0025] Figure 6 This is a perspective view of a linear cutting stapler with a self-locking function for a movable handle according to this utility model (handle housing is hidden);

[0026] Figure 7 This is a front view (closed and locked state) of a linear cutting stapler with a self-locking function of a movable handle according to this utility model;

[0027] Figure 8 This is a partial cross-sectional view (closed and locked state) of a linear cutting stapler with a self-locking function of a movable handle at the position of the hook assembly according to this utility model.

[0028] Figure 9 It is a 3D diagram of the handle frame;

[0029] Figure 10 It is a three-dimensional view of the handle shell from an upward angle;

[0030] Figure 11 It is a 3D diagram of the active handle.

[0031] In the diagram: 1. Lower jaw assembly; 2. Fixed handle; 3. Upper jaw assembly; 4. Movable handle; 5. Sewing advance button; 6. Hook assembly; 1-1. Rotating shaft one; 3-1. Upper jaw skeleton; 3-1a. Hole one; 3-1b. Hole two; 3-2. Nail cartridge gasket; 3-3. Slot; 3-4. Tail end shell; 4-1. Handle skeleton; 4-1a. Mounting hole one; 4-1b. Hook groove; 4-1c. Mounting hole two; 4-1d. Slot; 4-2. Handle shell; 4-2a. Screw hole post; 4-2b. Buckle; 4-2c. Baffle; 4-2d. Notch; 6-1. Pin; 6-2. Hook body; 6-2a. Connecting arm; 6-3. Arc-shaped reset spring; 6-4. Reset button. Detailed Implementation

[0032] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solution of this utility model and should not be construed as limiting the scope of protection of this utility model.

[0033] Example

[0034] like Figures 1-11As shown, this utility model is a linear cutting stapler with a self-locking movable handle, including a lower jaw assembly 1 and an upper jaw assembly 3. The upper jaw assembly 3 and the lower jaw assembly 1 are provided with a rotating hook assembly in the middle, allowing them to rotate and connect together. The lower jaw assembly 1 has a staple seat assembly at its left end and a fixed handle 2 at its right end. The upper jaw assembly 3 has a staple cartridge assembly at its left end, an upper jaw frame 3-1 at its right end, and a movable handle 4, inclined and extending above the upper jaw frame 3-1, hinged in the middle. The upper jaw frame 3-1 has an upwardly extending hook assembly 6 at its top. The linear cutting stapler has a closed and locked state and an unlocked state. In the closed and locked state, the movable handle 4, the upper jaw frame 3-1, and the fixed handle 2 are closed and tightly fitted together, and the hook assembly 6 is locked and connected to the movable handle 4. In the unlocked state, the hook assembly 6 is disengaged from the movable handle 4, and the movable handle 4 extends inclinedly above the upper jaw frame 3-1.

[0035] Preferably, the hook assembly 6 includes a pin 6-1, a hook body 6-2, an arc-shaped reset spring 6-3, and a reset knob 6-4. The pin 6-1 is rotatably mounted on the front and rear side walls of the upper jaw frame 3-1. The connecting arm 6-2a located at the lower end of the hook body 6-2 is fixedly mounted on the middle of the pin 6-1. The hook body 6-2 moves out from the hole 3-1a at the top of the upper jaw frame 3-1 and faces to the left. The top of the hook body 6-2 is designed to gradually curve from right to left. The downward-extending slope structure has one end of the arc-shaped reset spring 6-3 inserted and fixed inside the right side of the connecting arm 6-2a, and the other end passing through the right end of the channel 3-1a and overlapping and fixed to the top of the upper jaw frame 3-1. The concave arc side of the arc-shaped reset spring 6-3 faces downward. The reset button 6-4 is fixed to one end of the pin 6-1 that passes through and is located outside the upper jaw frame 3-1. In the closed and locked state, the hook 6-2 is engaged with the top right end of the movable handle 4.

[0036] More preferably, the reset button 6-4 is located on the front outer side of the upper jaw frame 3-1, and the upper jaw frame 3-1 is provided with a sewing push button 5 on the rear outer side.

[0037] More preferably, the upper jaw frame 3-1 is further provided with a nail box gasket 3-2 inside. The cross-section of the nail box gasket 3-2 is a U-shaped structure with the opening facing upwards. The two ends of the pin shaft 6-1 are also rotatably connected to the front and rear side walls of the nail box gasket 3-2.

[0038] More preferably, the movable handle 4 includes a handle frame 4-1 and a handle housing 4-2. The top of the handle frame 4-1 has a mounting hole 4-1c and a locking hole 4-1d located at the right end. The top of the handle housing 4-2 has a screw post 4-2a extending downward and a buckle 4-2b extending downward. The right end of the lower side of the top of the handle housing 4-2 also has baffles 4-2c located on the front and rear sides and a notch 4-2d located between the two baffles 4-2c. The handle housing 4-2 is correspondingly fastened and installed on the top of the handle frame 4-1. The two parts are fixedly connected together by screws that pass through the corresponding mounting holes 4-1c and screw holes 4-2a. The buckle 4-2b is inserted and fastened inside the buckle hole 4-1d. The right end of the handle frame 4-1 is located to the left of the two baffles 4-2c. The top of the upper jaw frame 3-1 also has a channel 3-1b for avoiding the lower end of the buckle 4-2b. In the closed and locked state, the hook 6-2 passes through the notch 4-2d and is engaged with the top of the right end of the handle frame 4-1.

[0039] More preferably, a tail end shell 3-4 is also installed at the right end of the upper jaw frame 3-1.

[0040] More preferably, the lower jaw assembly 1 has a pivot 1-1 extending outward to the front and rear sides in the middle, and the upper jaw assembly 3 is rotatably hooked to both ends of the pivot 1-1 in the middle of the lower jaw assembly 1 through a slot 3-3 located in the middle of the front and rear side walls and opening downward. The pivot 1-1 and the slot 3-3 constitute the rotating hook assembly.

[0041] The upper left side of the front and rear side walls of the handle frame 4-1 is provided with mounting holes 4-1a, and the lower left side of the front and rear side walls of the handle frame 4-1 is provided with hook grooves 4-1b with openings facing the left. The left end of the handle frame 4-1 is hinged to the upper middle part of the upper jaw assembly 3 through a pivot shaft 2 that passes through the mounting holes 4-1a on the front and rear sides. In the unlocked state, the hook grooves 4-1b on the front and rear sides of the left end of the handle frame 4-1 are engaged with the two ends of the pivot shaft 1-1.

[0042] The operating principle of this utility model of a linear cutting stapler with a self-locking function of a movable handle is as follows:

[0043] The clamping and cutting suture jaws between the upper jaw assembly 3 (upper staple cartridge assembly) and the lower jaw assembly 1 (upper staple seat assembly) hold the tissue to be cut and sutured. Then, the upper jaw assembly 3 and the lower jaw assembly 1 are rotated and connected together via a rotating hook assembly. At this point, the linear cutting stapler is in the unlocked state. Next, the movable handle 4 is pressed against the upper jaw skeleton 3-1 and the fixed handle 2 until the movable handle 4 is in contact with the upper jaw skeleton 3-1. At this point, the hook 6-2 on the hook assembly 6 passes through the notch 4-2d on the movable handle 4 and engages with the top right end of the handle skeleton 4-1 (see Appendix). Figure 8 Position ①), at this time the linear cutting stapler is in the closed and locked state, and the elastic driving force of the arc-shaped reset spring 6-3 keeps the hook 6-2 in a state of tight contact with the top right end of the handle frame 4-1; hold the movable handle 4 and the fixed handle 2 with one hand, and hold the suture advance button 5 with the other hand and push it towards the anvil assembly to perform subsequent cutting and suture operations; when it is necessary to change the staple cartridge, move the reset button 6-4 from bottom to top towards the anvil assembly, at this time the hook 6-2 moves away from the movable handle 4 and disengages from the right end of the handle frame 4-1 (see Appendix). Figure 8 Position ②), the linear cutting stapler changes from the closed and locked state back to the unlocked state, so that the upper jaw assembly 3 and the lower jaw assembly 1 can be separated and a new staple cartridge assembly can be replaced.

[0044] This utility model discloses a linear cutting stapler with a self-locking movable handle. In use, the clamping cutting and suturing jaws between the upper jaw assembly (upper staple cartridge) and the lower jaw assembly (upper staple seat) hold the tissue to be cut and sutured. Then, the upper and lower jaw assemblies are rotatably connected together via a rotating hook assembly. Next, the movable handle is pressed against the upper jaw skeleton and the fixed handle until it is flush with the upper jaw skeleton. At this point, the hook assembly on the upper jaw skeleton engages and locks with the movable handle, changing the linear cutting stapler from an unlocked state to a closed and locked state. This effectively prevents the movable handle from separating from the upper jaw skeleton during cutting and suturing, ensuring the stability and safety of the linear cutting stapler during surgical procedures. The overall structure is ingeniously and rationally designed, highly feasible to manufacture and implement, and highly practical.

[0045] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A linear cutting stapler with a self-locking movable handle, comprising a lower jaw assembly (1) and an upper jaw assembly (3), wherein the upper jaw assembly (3) and the lower jaw assembly (1) are provided with a rotating hook assembly for rotating and hooking them together, the lower jaw assembly (1) has a staple seat assembly at its left end and a fixed handle (2) at its right end, the upper jaw assembly (3) has a staple cartridge assembly at its left end and an upper jaw frame (3-1) at its right end, and a movable handle (4) extending obliquely above the upper jaw frame (3-1) is hinged in the middle, characterized in that, The upper jaw frame (3-1) has an upwardly extending hook assembly (6) at its top. The linear cutting stapler has a closed locking state and an unlocked state. In the closed locking state, the movable handle (4), the upper jaw frame (3-1), and the fixed handle (2) are closed and pressed together, and the hook assembly (6) is fastened and locked together with the movable handle (4). In the unlocked state, the hook assembly (6) is disengaged from the movable handle (4), and the movable handle (4) extends obliquely above the upper jaw frame (3-1).

2. The linear cutting stapler with a self-locking function of the movable handle as described in claim 1, characterized in that, The hook assembly (6) includes a pin (6-1), a hook body (6-2), an arc-shaped reset spring (6-3), and a reset knob (6-4). The pin (6-1) is rotatably mounted on the front and rear side walls of the upper jaw frame (3-1). The connecting arm (6-2a) located at the lower end of the hook body (6-2) is fixedly mounted on the middle of the pin (6-1). The hook body (6-2) moves out from the hole (3-1a) at the top of the upper jaw frame (3-1) and faces to the left. The top of the hook body (6-2) is designed to gradually extend from right to left. The downward-extending slope structure has one end of the arc-shaped reset spring (6-3) inserted and fixed inside the right side of the connecting arm (6-2a), and the other end passing through the right end of the first hole (3-1a) and overlapping and fixed to the top of the upper jaw frame (3-1). The concave arc side of the arc-shaped reset spring (6-3) faces downward. The reset knob (6-4) is fixed to one end of the pin (6-1) that passes through and is located outside the upper jaw frame (3-1). In the closed and locked state, the hook (6-2) is engaged with the top right end of the movable handle (4).

3. The linear cutting stapler with a self-locking function of the movable handle as described in claim 2, characterized in that, The reset button (6-4) is located on the front outer side of the upper jaw frame (3-1), and the upper jaw frame (3-1) is provided with a stitching push button (5) on the rear outer side.

4. The linear cutting stapler with a self-locking function of the movable handle as described in claim 3, characterized in that, The upper jaw frame (3-1) is also provided with a nail box gasket (3-2) inside. The cross-section of the nail box gasket (3-2) is a U-shaped structure with the opening facing upward. The two ends of the pin (6-1) are also rotatably connected to the front and rear side walls of the nail box gasket (3-2).

5. The linear cutting stapler with a self-locking function of the movable handle as described in claim 4, characterized in that, The movable handle (4) includes a handle frame (4-1) and a handle shell (4-2). The top of the handle frame (4-1) has a mounting hole (4-1c) and a snap hole (4-1d) located at the right end. The top of the handle shell (4-2) has a screw post (4-2a) extending downward and a snap fastener (4-2b) extending downward. The right end of the lower side of the top of the handle shell (4-2) also has baffles (4-2c) located on the front and rear sides and a notch (4-2d) located between the two baffles (4-2c). The handle shell (4-2) is correspondingly fastened and installed on the top of the handle frame (4-1). The two parts are fixedly connected together by screws that pass through the corresponding mounting hole 2 (4-1c) and screw hole post (4-2a), and the buckle (4-2b) is inserted and fastened into the buckle hole (4-1d). The right end of the handle frame (4-1) is located on the left side of the two baffles (4-2c). The top of the upper jaw frame (3-1) also has a channel 2 (3-1b) for avoiding the lower end of the buckle (4-2b). In the closed and locked state, the hook (6-2) passes through the notch groove (4-2d) and is engaged with the top of the right end of the handle frame (4-1).

6. The linear cutting stapler with a self-locking function of the movable handle as described in claim 5, characterized in that, A tail end shell (3-4) is also installed at the right end of the upper jaw frame (3-1).

7. The linear cutting stapler with a self-locking function of the movable handle as described in claim 6, characterized in that, The lower jaw assembly (1) has a pivot (1-1) extending outward to the front and rear sides in the middle. The upper jaw assembly (3) is rotatably hooked to both ends of the pivot (1-1) in the middle of the lower jaw assembly (1) through a slot (3-3) located in the middle of the front and rear side walls and opening downward. The pivot (1-1) and the slot (3-3) constitute the rotating hook assembly. The upper left side of the front and rear side walls of the handle frame (4-1) is provided with mounting hole 1 (4-1a), and the lower left side of the front and rear side walls of the handle frame (4-1) is provided with hook groove (4-1b) with opening facing the left. The left end of the handle frame (4-1) is hinged to the upper middle part of the upper jaw assembly (3) through the rotating shaft 2 passing through the mounting hole 1 (4-1a) on the front and rear sides. In the unlocked state, the hook groove (4-1b) on the front and rear sides of the left end of the handle frame (4-1) is engaged with the two ends of the rotating shaft 1 (1-1).

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