Labor-saving forceps with replaceable tips

Abstract

The present application relates to a kind of labor-saving forceps of head replacement, when replacing head, user only needs to separate left handle and right handle as far as possible, make left pin and right pin as close as possible, the interval between the outside of left pin and the outside of right pin is less than the interval between the upper side of left clamping groove and right clamping groove on the side away from first pivot shaft, so that user can directly take off left and right handle from left and right connecting arm, similarly, by the above-mentioned operation to left handle and right handle, left and right handle can also be directly assembled to the left and right connecting arm of another forceps head, so as to achieve the technical goal of disassembling and replacing forceps head without contacting forceps head, solve the technical problem of inconvenient head replacement of current forceps with replaceable head.

Description

Technical Field

[0001] This invention belongs to the field of hardware tool technology, specifically relating to a labor-saving pair of pliers that facilitates head replacement. Background Technology

[0002] Pliers are a common hardware tool in daily life and production, mainly used for clamping and cutting workpieces. Depending on different work requirements, pliers have also evolved to perform various functions such as wire stripping, wire crimping, and bending. Therefore, there are many types of pliers, and users often keep multiple different types on hand. The more pliers they have, the higher the cost and the more inconvenient it is to carry. To solve this technical problem, existing technology uses interchangeable plier heads, allowing one plier handle to be compatible with multiple plier heads of different functions or sizes. This achieves multiple functions while reducing the overall weight of the tool, lowering production costs, and improving portability.

[0003] The invention patent with patent number "202020858194.X" discloses a multi-specification easy-to-change pliers. When changing the head of this pliers, one hand needs to hold the pliers head to close the head, and the other hand needs to hold the handle to close the handle. Then the head and handle are separated. However, the pliers head is sometimes very dirty after use. When the user holds the pliers head to close it, it will contaminate the gloves or palm. When the contaminated gloves or palm hold the handle again, it will contaminate the handle. Therefore, it is difficult to keep the pliers handle and the user's hands or gloves clean when using this pliers in a poor working environment. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a force-saving pliers that is easy to change heads, thereby solving the technical problem of inconvenient head-changing operation of current interchangeable head pliers.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a labor-saving pliers for easy head changing, comprising a left and a right jaw hinged together, and a left and a right handle hinged together. The left jaw has a left pivot fixedly connected to its rear end, and the right jaw has a right pivot fixedly connected to its rear end. The left and right pivots overlap and are hinged together by a first pivot shaft. A left connecting arm extending to the left rear is connected to the left pivot, and a right connecting arm extending to the right rear is connected to the right pivot. The left connecting arm and the right... When the connecting arms move away from each other, the left and right jaws move closer together. A left clamping groove facing right is located on the rear edge of the left connecting arm near the right connecting arm, and a right clamping groove facing left is located on the rear edge of the right connecting arm near the left connecting arm. A spring is installed between the left and right pivot joints or between the left and right connecting arms. The elastic potential energy of the spring drives the left and right jaws to open and maintains a certain angle α between the left and right connecting arms. The components include the left jaw, right jaw, left pivot joint, right pivot joint, first pivot shaft, left connecting arm, right connecting arm, and spring. The springs together form a clamp head; a left hinge seat extending towards the right handle is fixedly connected to the front part of the left handle near the right handle, and a right hinge seat extending towards the left handle and cooperating with the left hinge seat is fixedly connected to the front part of the right handle near the left handle. The left and right hinge seats overlap each other and are hinged together by a second pivot axis, which is parallel to the first pivot axis. Two left clamping plates extend forward from the front end of the left handle, which are parallel to each other and perpendicular to the first pivot axis. A left clamping rod parallel to the first pivot axis connects the two left clamping plates. The left and right clamping pins are matched with the left clamping slot. Two right clamping plates extend forward from the front end of the right handle, which are parallel to each other and perpendicular to the first pivot axis. A right clamping pin is connected between the two right clamping plates, which is parallel to the first pivot axis and matches the right clamping slot. The left and right clamping pins are detachably engaged in the left and right clamping slots, respectively. When the included angle between the left and right connecting arms is α, the distance between the upper edges of the left and right clamping slots on the side away from the first pivot axis is greater than the minimum distance between the left side of the left clamping pin and the right side of the right clamping pin.

[0006] As a preferred embodiment, a blind hole is provided on the opposite side of the left and right connecting arms, with the openings of the two blind holes facing each other. The two ends of the spring are inserted into the two blind holes one by one and are fixedly connected to the left and right connecting arms by positioning pins that pass through the blind holes.

[0007] As a preferred embodiment, the rear end of the left connecting arm is a left clamping part whose thickness is adapted to the spacing between the two left clamping pieces, and a left clamping groove is provided in the left clamping part; the rear end of the right connecting arm is a right clamping part whose thickness is adapted to the spacing between the two right clamping pieces, and a right clamping groove is provided in the right clamping part.

[0008] As a preferred embodiment, the left rear side and rear end face of the left connecting arm are smoothly transitioned by an arc surface, forming an arc-shaped left gripper that bends backward and to the right at the rear end of the left connecting arm. The left gripper and the left connecting arm in front of it form a left clamping groove. Similarly, the right rear side and rear end face of the right connecting arm are smoothly transitioned by an arc surface, forming an arc-shaped right gripper that bends backward and to the left at the rear end of the right connecting arm. The right gripper and the right connecting arm in front of it form a right clamping groove. The left side of the two left clamping pieces forms a left insertion port for the left gripper to insert into. After the left gripper inserts into the two left clamping pieces through the left insertion port, the left locking pin is just inserted into the left clamping groove. The right side of the two right clamping pieces forms a right insertion port for the right gripper to insert into. After the right gripper inserts into the two right clamping pieces through the right insertion port, the right locking pin is just inserted into the right clamping groove.

[0009] As a preferred embodiment, the second pivot shaft is located at the front of the left hinge seat, and a locking hole with an axial direction parallel to the second pivot shaft is opened at the rear of the left hinge seat. The locking hole is an elongated hole. A locking groove extending forward is opened at the rear end of the right hinge seat. The part of the right hinge seat located on the side of the locking groove biased towards the left handle forms a locking hook. When the left and right pliers are closed, the axis of the first pivot shaft and the axis of the second pivot shaft are both located on the extension line of the major diameter of the locking hole, and the locking hole coincides with the locking groove. A locking pin is inserted into the locking hole. The locking pin can slide back and forth along the major diameter of the locking hole. When the locking groove coincides with the locking hole, the locking pin slides into the locking groove to lock the left and right handles together. When the locking pin slides out of the locking groove, the left and right handles are unlocked. The length of the locking hook is less than the difference between the major diameter of the locking hole and the diameter of the locking pin.

[0010] As a preferred embodiment, a torsion spring is sleeved on the second pivot shaft. One end of the torsion spring abuts against the left baffle inside the left handle or the left hinge seat, and the other end of the torsion spring abuts against the right baffle inside the right handle or the right hinge seat. The torque of the torsion spring drives the left and right locking pins to be stably engaged in the left and right clamping slots.

[0011] The beneficial effects of the present invention are as follows: When changing the head of the pliers described in this invention, the user only needs to separate the left and right handles as much as possible, making the left and right locking pins as close as possible, and making the distance between the outer side of the left locking pin and the outer side of the right locking pin less than the distance between the upper edges of the left and right clamping slots on the side away from the first pivot shaft. In this way, the user can directly remove the left and right handles from the left and right connecting arms. Similarly, through the above-mentioned operation of the left and right handles, the left and right handles can also be directly assembled onto the left and right connecting arms of another pliers head, thereby achieving the technical goal of disassembling and replacing the pliers head without contacting the pliers head, and solving the technical problem of inconvenient head changing operation of current interchangeable pliers. Attached Figure Description

[0012] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings, wherein: Figure 1This is an exploded view of the three-dimensional structure of the present invention; Figure 2 It is a three-dimensional diagram showing the specific connection structure of the left clamp head, the left pivot joint, and the left connecting arm; Figure 3 It is a three-dimensional diagram of the specific connection structure of the right clamp head, the right pivot joint, and the right connecting arm; Figure 4 This is a partial 3D structural diagram of the left handle; Figure 5 This is a partial 3D structural diagram of the right handle; Figure 6 This is a sectional view showing the connection relationship between the left and right handles and the pliers head; Figure 7 This is a diagram showing the state when the left and right handles are separated from the pliers head; Figures 1-7 In the middle: 1. Left jaw, 2. Right jaw, 3. Left handle, 4. Right handle, 5. Left pivot, 6. Right pivot, 7. First pivot shaft, 8. Left connecting arm, 9. Right connecting arm, 10. Left clamping groove, 11. Right clamping groove, 12. Spring, 13. Left hinge, 14. Right hinge, 15. Second pivot shaft, 16. Left clamping piece, 17. Left locking pin, 18. Right clamping piece, 19. Right locking pin, 20. Blind hole, 21. Positioning pin, 22. Left clamping part, 23. Right clamping part, 24. Left jaw, 25. Right jaw, 26. Left insertion port, 27. Right insertion port, 28. Locking hole, 29. Locking groove, 30. Locking hook, 31. Locking pin, 32. Torsion spring, 33. Left baffle, 34. Right baffle. Detailed Implementation

[0013] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0014] like Figures 1-7 The illustrated easy-to-change-head pliers include a left jaw 1 and a right jaw 2 hinged together, a left handle 3 and a right handle 4 hinged together, and the rear end of the left jaw 1 ( Figure 1 The lower end of the pliers 1 shown is fixedly connected to a left pivot part 5, and the rear end of the right pliers 2 is fixedly connected to a right pivot part 6. The left pivot part 5 and the right pivot part 6 are overlapped and hinged together by a first pivot shaft 7. A left connecting arm 8 extending to the left rear is connected to the left pivot part 5, and a right connecting arm 9 extending to the right rear is connected to the right pivot part 6. When the left connecting arm 8 and the right connecting arm 9 are far apart, the left pliers 1 and the right pliers 2 are close to each other.

[0015] like Figure 2 and Figure 3 As shown, a left clamping groove 10 facing right is provided on the side edge of the rear end of the left connecting arm 8 near the right connecting arm 9, and a right clamping groove 11 facing left is provided on the side edge of the rear end of the right connecting arm 9 near the left connecting arm 8. Figure 1As shown, a spring 12 is provided between the left pivot 5 and the right pivot 6, or between the left connecting arm 8 and the right connecting arm 9. The elastic potential energy of the spring 12 drives the left jaw 1 and the right jaw 2 to open and keeps the left connecting arm 8 and the right connecting arm 9 at a certain angle α. In this embodiment, the angle α is 14°. In actual application, the size of the angle α can be adjusted as needed. The left jaw 1, the right jaw 2, the left pivot 5, the right pivot 6, the first pivot shaft 7, the left connecting arm 8, the right connecting arm 9, and the spring 12 together constitute a jaw.

[0016] A left hinge seat 13 extending towards the right handle 4 is fixedly connected to the front part of the left handle 3 near the side of the right handle 4. A right hinge seat 14 extending towards the left handle 3 and cooperating with the left hinge seat 13 is fixedly connected to the front part of the right handle 4 near the side of the left handle 3. The left hinge seat 13 and the right hinge seat 14 overlap each other and are hinged together by a second pivot shaft 15, which is parallel to the first pivot shaft 7. Two left clamping pieces 16 extend forward from the front end of the left handle 3, which are parallel to each other and perpendicular to the first pivot shaft 7. A left locking pin 17 parallel to the first pivot shaft 7 is connected between the two left clamping pieces 16. The left locking pin 17 matches the left clamping groove 10. Two right clamping pieces 18 extend forward from the front end of the right handle 4, which are parallel to each other and perpendicular to the first pivot shaft 7. A right locking pin 19 parallel to the first pivot shaft 7 is connected between the two right clamping pieces 18. The right locking pin 19 matches the right clamping groove 11.

[0017] like Figure 6 and Figure 7 As shown, the left locking pin 17 and the right locking pin 19 are detachably locked in the left clamping groove 10 and the right clamping groove 11, respectively. When the included angle between the left connecting arm 8 and the right connecting arm 9 is α, the spring 12 has no elastic potential energy. At this time, the distance L between the upper edges of the left clamping groove 10 and the right clamping groove 11 away from the first pivot shaft 7 is greater than the minimum distance S between the left side of the left locking pin 17 and the right side of the right locking pin 19. That is, when the minimum distance S between the left side of the left locking pin 17 and the right side of the right locking pin 19 is less than L, the left handle 3 and the right handle 4 can be automatically removed from the pliers. The user does not need to use his hands to grip the left pliers 1 and the right pliers 2 to close them.

[0018] like Figure 2 and Figure 3 As shown, a blind hole 20 is opened on each of the left connecting arm 8 and the right connecting arm 9 on opposite sides. The openings of the two blind holes 20 are opposite to each other, and combined with... Figure 1 As shown, the two ends of the spring 12 are inserted into the two blind holes 20 one by one and are fixedly connected to the left arm 8 and the right arm 9 respectively by the positioning pins 21 that pass through the blind holes 20.

[0019] In practical applications, the spring 12 can also be installed between the left pivot 5 and the right pivot 6, and sleeved on the first pivot shaft 7, as shown in the structure of a multi-specification easy-to-change pliers disclosed in the invention patent with patent number "202020858194.X".

[0020] The rear end of the left connecting arm 8 has a left clamping portion 22 whose thickness is adapted to the spacing between the two left clamping plates 16, in order to improve the connection stability between the left connecting arm 8 and the left handle 3. A left clamping groove 10 is provided in the left clamping portion 22. The rear end of the right connecting arm 9 has a right clamping portion 23 whose thickness is adapted to the spacing between the two right clamping plates 18, in order to improve the connection stability between the right connecting arm 9 and the right handle 4. A right clamping groove 11 is provided in the right clamping portion 23.

[0021] In this embodiment, the left rear side and rear end face of the left connecting arm 8 are smoothly transitioned by an arc surface, forming a rearward and rightward curved arc-shaped left gripper 24 at the rear end of the left connecting arm 8. The left gripper 24 and the left connecting arm 8 in front of it form a left clamping groove 10. Similarly, the right rear side and rear end face of the right connecting arm 9 are smoothly transitioned by an arc surface, forming a rearward and leftward curved arc-shaped right gripper 25 at the rear end of the right connecting arm 9. The right gripper 25 and the right connecting arm 9 in front of it form a left clamping groove 10. The left side of the two left clamping pieces 16 forms a left insertion port 26 for the left clamping claw 24 to be inserted. After the left clamping claw 24 is inserted into the two left clamping pieces 16 through the left insertion port 26, the left locking pin 17 is just inserted into the left clamping groove 10. The right side of the two right clamping pieces 18 forms a right insertion port 27 for the right clamping claw 25 to be inserted. After the right clamping claw 25 is inserted into the two right clamping pieces 18 through the right insertion port 27, the right locking pin 19 is just inserted into the right clamping groove 11.

[0022] The curved left jaw 24 and right jaw 25 are more conducive to insertion into the left insertion port 26 and right insertion port 27, and also allow for a larger distance between the free ends of the left jaw 24 and right jaw 25, making it easier for the left locking pin 17 and right locking pin 19 to engage and disengage.

[0023] Based on the above technical solution, this embodiment makes the following further improvements: Figure 1 , Figure 4 and Figure 5The second pivot shaft 15 is located at the front of the left hinge seat 13. A locking hole 28, axially parallel to the second pivot shaft 15, is opened at the rear of the left hinge seat 13. The locking hole 28 is an elongated hole. A locking groove 29 extending forward is opened at the rear end of the right hinge seat 14. The portion of the right hinge seat 14 located on the side of the locking groove 29 biased towards the left handle 3 forms a locking hook 30. When the left pliers 1 and right pliers 2 are closed, the axes of the first pivot shaft 7 and the second pivot shaft 15 are both located at the locking point. On the extended line of the major diameter of the hole 28, and the locking hole 28 coincides with the locking groove 29, a locking pin 31 is inserted into the locking hole 28. The locking pin 31 can slide back and forth along the major diameter of the locking hole 28. When the locking groove 29 coincides with the locking hole 28, the locking pin 31 slides into the locking groove 29 to lock the left handle 3 and the right handle 4 together. When the locking pin 31 slides out of the locking groove 29, the left handle 3 and the right handle 4 are unlocked. The length of the locking hook 30 is less than the difference between the major diameter of the locking hole 28 and the diameter of the locking pin 31.

[0024] The above structure allows the left handle 3 and the right handle 4 to lock together, preventing the jaws of the pliers from being constantly open when the user is not using them, which is inconvenient to carry, and also preventing the handles and pliers head from automatically detaching.

[0025] In this embodiment, a torsion spring 32 is further fitted onto the second pivot shaft 15. One end of the torsion spring 32 abuts against the left baffle 33 inside the left hinge seat 13, and the other end of the torsion spring 32 abuts against the right baffle 34 inside the right hinge seat 14. The torque of the torsion spring 32 drives the left locking pin 17 and the right locking pin 19 to be stably engaged in the left clamping groove 10 and the right clamping groove 11. After the torsion spring 32 is set, the left handle 3 and the right handle 4 are kept connected to the pliers head by the elastic force of the torsion spring 32. When the user needs to replace the pliers head, he can forcefully overcome the elastic force of the torsion spring 32 to bring the left locking pin 17 and the right locking pin 19 closer together.

[0026] The working process of this invention is as follows: When the user needs to connect a new pliers head and handle, the user can hold the left handle 3 and the right handle 4 to separate the left handle 3 and the right handle 4 to the maximum angle, so that the distance between the left locking pin 17 and the right locking pin 19 is minimized. At this time, the user can directly insert the left locking pin 17 and the right locking pin 19 between the left jaw 24 at the rear end of the left connecting arm 8 of the pliers head and the right jaw 25 at the right end of the right connecting arm 9, and lock the left locking pin 17 and the right locking pin 19 into the left clamping groove 10 and the right clamping groove 11 respectively.

[0027] Then the user can close the left handle 3 and the right handle 4, and the jaws will be stably and reliably connected to the left handle 3 and the right handle 4. When the user grips the left handle 3 and the right handle 4 to bring them closer together, the left locking pin 17 and the right locking pin 19 will separate further, driving the left connecting arm 8 and the right connecting arm 9 to separate outwards, while the left jaw 1 and the right jaw 2 will come closer together to clamp or cut the workpiece.

[0028] When the user needs to replace the pliers head, the user can insert the pliers head into the storage slot or suspend it downwards. The user then holds the left handle 3 and the right handle 4 again, separating them to their maximum angle to minimize the distance between the left locking pin 17 and the right locking pin 19. At this point, the user can directly remove the left handle 3 and the right handle 4 from the left jaw 24 and the right jaw 25 at the rear of the pliers head, or allow the pliers head to detach directly from the front end of the left handle 3 and the right handle 4. The user can then repeat the above process of connecting the new pliers head to replace it.

[0029] The technical solution described in this invention eliminates the need for users to hold the pliers head when changing it, thus greatly improving the convenience of pliers head replacement and avoiding the technical problem of contamination of the user's hands or gloves by the pliers head.

[0030] The above embodiments are merely illustrative of the principles and effects of the present invention, as well as some of the application examples, and are not intended to limit the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the inventive concept of the present invention, and these modifications and improvements all fall within the protection scope of the present invention.

Claims

1. A pair of force-saving pliers for easy head changing, comprising a left plier head (1) and a right plier head (2) hinged together, and a left handle (3) and a right handle (4) hinged together, characterized in that, The rear end of the left jaw (1) is fixedly connected to a left pivot (5), and the rear end of the right jaw (2) is fixedly connected to a right pivot (6). The left pivot (5) and the right pivot (6) are overlapped and hinged together by a first pivot shaft (7). A left connecting arm (8) extending to the left rear is connected to the left pivot (5), and a right connecting arm (9) extending to the right rear is connected to the right pivot (6). When the left connecting arm (8) and the right connecting arm (9) are far apart, the left jaw (1) and the right jaw (2) are close to each other. A left clamping groove facing the right is opened on the side edge of the rear end of the left connecting arm (8) near the right connecting arm (9). 10) A right clamping groove (11) facing the left is provided on one side edge of the rear end of the right arm (9) near the left arm (8). A spring (12) is provided between the left pivot (5) and the right pivot (6) or between the left arm (8) and the right arm (9). The elastic potential energy of the spring (12) drives the left clamp head (1) and the right clamp head (2) to open and keep the left arm (8) and the right arm (9) at a certain angle α. The left clamp head (1), the right clamp head (2), the left pivot (5), the right pivot (6), the first pivot shaft (7), the left arm (8), the right arm (9) and the spring (12) together constitute a clamp head. A left hinge seat (13) extending towards the right handle (4) is fixedly connected to the front part of the left handle (3) near the right handle (4). A right hinge seat (14) extending towards the left handle (3) and cooperating with the left hinge seat (13) is fixedly connected to the front part of the right handle (4) near the left handle (3). The left hinge seat (13) and the right hinge seat (14) overlap each other and are hinged together by a second pivot shaft (15). The second pivot shaft (15) is parallel to the first pivot shaft (7). Two parallel pieces extend forward from the front end of the left handle (3). The left clamping piece (16) is perpendicular to the first pivot shaft (7). A left locking pin (17) parallel to the first pivot shaft (7) is connected between the two left clamping pieces (16). The left locking pin (17) matches the left clamping groove (10). Two right clamping pieces (18) parallel to each other and perpendicular to the first pivot shaft (7) extend forward from the front end of the right handle (4). A right locking pin (19) parallel to the first pivot shaft (7) is connected between the two right clamping pieces (18). The right locking pin (19) matches the right clamping groove (11). The left locking pin (17) and the right locking pin (19) are detachably locked in the left clamping groove (10) and the right clamping groove (11), respectively. When the included angle between the left connecting arm (8) and the right connecting arm (9) is α, the distance between the upper edge of the left clamping groove (10) and the right clamping groove (11) away from the first pivot shaft (7) is greater than the minimum distance between the left side of the left locking pin (17) and the right side of the right locking pin (19).

2. The easy-to-change, labor-saving pliers according to claim 1, characterized in that, A blind hole (20) is opened on the opposite side of the left arm (8) and the right arm (9). The two blind holes (20) are opposite to each other. The two ends of the spring (12) are inserted into the two blind holes (20) one by one and are fixedly connected to the left arm (8) and the right arm (9) by the positioning pin (21) that passes through the blind hole (20).

3. The easy-to-change, labor-saving pliers according to claim 1, characterized in that, The rear end of the left connecting arm (8) is a left clamping part (22) whose thickness is adapted to the distance between the two left clamping pieces (16), and a left clamping groove (10) is provided in the left clamping part (22). The rear end of the right connecting arm (9) is a right clamping part (23) whose thickness is adapted to the distance between the two right clamping pieces (18), and a right clamping groove (11) is provided in the right clamping part (23).

4. The easy-to-change, labor-saving pliers according to claim 1, characterized in that, The left and rear sides of the left connecting arm (8) are smoothly transitioned by an arc surface, forming a curved left gripper (24) that bends backward and to the right. The left gripper (24) forms a left clamping groove (10) with the left connecting arm (8) in front of it. The right and rear sides of the right connecting arm (9) are smoothly transitioned by an arc surface, forming a curved right gripper (25) that bends backward and to the left. The right gripper (25) forms a right clamping groove (11) with the right connecting arm (9) in front of it. The left side of the two left clamping pieces (16) forms a left insertion port (26) for the left clamping claw (24) to be inserted. After the left clamping claw (24) is inserted into the two left clamping pieces (16) through the left insertion port (26), the left locking pin (17) is just inserted into the left clamping groove (10). The right side of the two right clamping pieces (18) forms a right insertion port (27) for the right clamping claw (25) to be inserted. After the right clamping claw (25) is inserted into the two right clamping pieces (18) through the right insertion port (27), the right locking pin (19) is just inserted into the right clamping groove (11).

5. The easy-to-change, labor-saving pliers according to claim 1, characterized in that, The second pivot shaft (15) is located at the front of the left hinge seat (13). The rear of the left hinge seat (13) has a locking hole (28) axially parallel to the second pivot shaft (15). The locking hole (28) is an elongated hole. The rear end of the right hinge seat (14) has a locking groove (29) extending forward. The part of the right hinge seat (14) located on the side of the locking groove (29) biased towards the left handle (3) forms a locking hook (30). When the left pliers (1) and the right pliers (2) are closed, the axis of the first pivot shaft (7) and the axis of the second pivot shaft (15) are both located in the locking hole (28). On the extended line of the major diameter of the locking hole (28) and the locking groove (29), a locking pin (31) is inserted into the locking hole (28). The locking pin (31) can slide back and forth along the major diameter of the locking hole (28). When the locking groove (29) coincides with the locking hole (28), the locking pin (31) slides into the locking groove (29) to lock the left handle (3) and the right handle (4) together. When the locking pin (31) slides out of the locking groove (29), the left handle (3) and the right handle (4) are unlocked. The length of the locking hook (30) is less than the difference between the major diameter of the locking hole (28) and the diameter of the locking pin (31).

6. The easy-to-change, labor-saving pliers according to claim 1, characterized in that, A torsion spring (32) is sleeved on the second pivot shaft (15). One end of the torsion spring (32) abuts against the left baffle (33) inside the left handle (3) or the left hinge seat (13), and the other end of the torsion spring (32) abuts against the right baffle (34) inside the right handle (4) or the right hinge seat (14). The torque of the torsion spring (32) drives the left locking pin (17) and the right locking pin (19) to be stably locked in the left clamping groove (10) and the right clamping groove (11).

Images