Special thoracolumbar intervertebral disc dividing device for thoracolumbar vertebral body total resection

Abstract

The invention belongs to the technical field of medical instruments, and discloses a special thoracolumbar intervertebral disc separator for thoracolumbar vertebral body total resection, which comprises a grip, the outer surface of the grip is fixedly sleeved with an anti-slip ring, the middle of the bottom end of the grip is fixedly provided with an extension plate, and the rear side of the middle end in the extension plate is fixedly sleeved with a limiting rod. By arranging a limiting rod, a first gear, a tooth plate, an inclined rod and a movable block, when a hexagonal handle is rotated, a threaded rod can rotate, due to the fact that the outer surface of the threaded rod and the inner surface of the movable block are connected in a threaded and sleeving mode, along with rotation of the threaded rod, the movable block can drive one end of the inclined rod to move, and the inclined rod is driven to rotate; the inclined rod is driven to rotate, so that the other end of the inclined rod generates thrust on the rectangular block, the rectangular block is pushed to drive the two tooth plates to move oppositely, the tooth plates are separated from the first gear, then the first gear can be pushed to adjust the position of the first gear, and the first gear is fixed through the tooth plates after adjustment is completed.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and specifically relates to a thoracolumbar disc dissector dedicated for total resection of thoracolumbar vertebrae. Background Art

[0002] Thoracolumbar vertebrae refer to the collective name of thoracic vertebrae and lumbar vertebrae. They are both important components of the human spine, with different structural and functional characteristics. Thoracolumbar vertebrae jointly support the upper body of the human body, enabling the human body to maintain a normal standing and walking posture. The thoracic vertebrae are connected to the ribs to jointly form the thoracic cavity, protecting organs in the thoracic cavity such as the heart and lungs. The lumbar vertebrae protect important structures such as the spinal cord and nerve roots.

[0003] When performing total resection of thoracolumbar vertebrae, in order to improve the surgical efficiency, a corresponding thoracolumbar disc dissector is required to assist in the dissection operation. However, in the actual use process of the existing thoracolumbar disc dissector, most of the structures between the blade and the handle are designed in a fixed manner, so that the relative position between the blade and the handle cannot be adjusted. As a result, the length of the dissector is fixed. Due to the particularity of the surgical site, the fixed structural design makes the depth of the blade inserted into the human body during the operation fixed, thus limiting the applicable range of the thoracolumbar disc dissector. Even the handle may block the line of sight, bringing inconvenience to the operation. Therefore, it is necessary to improve this. Summary of the Invention

[0004] The purpose of the present invention is to provide a thoracolumbar disc dissector dedicated for total resection of thoracolumbar vertebrae to solve the problems raised in the above background art.

[0005] To achieve the above object, the present invention provides the following technical solution: a special thoracolumbar disc dissector for total resection of thoracolumbar vertebrae, including a grip. An anti-slip ring is fixedly sleeved on the outer surface of the grip. A extension plate is fixedly installed in the middle of the bottom end of the grip. A limiting rod is fixedly sleeved at the rear side of the middle end inside the extension plate. A first gear is movably sleeved on the top of the outer surface of the limiting rod. Tooth plates are respectively movably sleeved on the inner surfaces of the left and right ends of the extension plate. The number of the tooth plates is two. The tops of the opposite surfaces of the two tooth plates are respectively meshed and connected with the left and right sides of the outer surface of the first gear. Rectangular blocks are respectively fixedly installed at the tops of the two tooth plates. The outer surface of the rectangular block is movably sleeved with the inner surface of the top end of the extension plate. A round rod is movably sleeved inside the rectangular block. The outer surface of the round rod is fixedly sleeved with the inner surface of the top end of the extension plate. An inclined rod is hinged at the top end of the rectangular block. The other end of the inclined rod is hinged with a movable block. The outer surface of the movable block is movably sleeved with the inner surface of the bottom end of the grip. A threaded rod is threadedly sleeved inside the movable block. The outer surface of the threaded rod is movably sleeved with the inner surface of the middle end of the grip. A hexagonal handle is fixedly sleeved on the top of the outer surface of the threaded rod. The outer surface of the hexagonal handle is movably sleeved with the inner surface of the grip.

[0006] Preferably, a fixing plate located outside the extension plate is fixedly installed on the outer surface of the first gear. A round shaft is movably sleeved inside the middle end of the fixing plate.

[0007] Preferably, a knife handle is fixedly sleeved on the left side of the outer surface of the round shaft. The outer surface of the knife handle is movably connected with the outer surface of the fixing plate. A second gear is fixedly sleeved on the right side of the outer surface of the round shaft. The outer surface of the second gear is movably sleeved with the inner surface of the fixing plate.

[0008] Preferably, a long rod is movably connected to the right side of the outer surface of the second gear. The right end of the long rod penetrates through the fixing plate and extends to the outside of the fixing plate. A short rod is fixedly sleeved inside the right end of the long rod. A rotating frame is movably sleeved on the outer surface of the short rod. The outer surface of the rotating frame is movably connected with the outer surface of the fixing plate. A dial is fixedly installed on the right side of the top end of the rotating frame.

[0009] Preferably, a fixing block is movably sleeved inside the right end of the long rod. The right end of the fixing block is fixedly connected with the right inner wall of the fixing plate. A first spring is fixedly installed at the left end of the fixing block. The other end of the first spring is fixedly installed on the left inner wall of the long rod.

[0010] Preferably, a blade is fixedly installed at the bottom end of the knife handle. A visual lens is fixedly sleeved inside the right end of the blade.

[0011] As a preferred embodiment of the present invention, a clamping plate is fixedly installed on the right side of the top of the blade, and the outer surface of the clamping plate is movably connected to the inner surface of the bottom end of the handle. A connecting rod is fixedly installed on the left end of the clamping plate, and the outer surface of the connecting rod is movably connected to the inner surface of the bottom left end of the handle.

[0012] As a preferred embodiment of the present invention, a rectangular groove is provided inside the connecting rod, a clamping block is movably sleeved inside the rectangular groove, and the right end of the clamping block is movably connected to the left end of the knife handle.

[0013] As a preferred embodiment of the present invention, a T-block is movably sleeved on the rear end of the clamping block, the right end of the T-block is fixedly connected to the left end of the knife handle, a second spring is fixedly installed on the front end of the T-block, and the other end of the second spring is fixedly connected to the inner surface of the clamping block.

[0014] The beneficial effects of the present invention are as follows:

[0015] 1. The present invention provides a limit rod, a first gear, a tooth plate, an inclined rod and a movable block. When the hexagonal handle is turned, the threaded rod will rotate. Since the outer surface of the threaded rod and the inner surface of the movable block are threadedly sleeved, the movable block will move with one end of the inclined rod as the threaded rod rotates, so that the other end of the inclined rod generates a thrust on the rectangular block, pushing the rectangular block to move the two tooth plates in opposite directions, thereby separating the tooth plate and the first gear. Subsequently, the first gear can be pushed to adjust the position of the first gear and fixed to it by the tooth plate after the adjustment is completed, thereby realizing the adjustment of the length of the disconnector.

[0016] 2. The present invention provides a circular shaft, a second gear, a long rod, a rotating frame and a first spring. When the paddle is turned, the rotating frame will rotate with the short rod as the axis. Since the short rod is movably sleeved inside the rotating frame, as the rotating frame rotates, the short rod will move with the long rod and compress the first spring. When the rotating frame rotates ninety degrees, the fixation of the long rod to the second gear can be released. At this time, the knife handle can be turned to make the knife handle rotate with the second gear and the blade with the circular shaft as the axis, thereby adjusting the angle and direction of the blade, which is convenient for cutting the inter-disk.

[0017] 3. The present invention provides a connecting rod, a rectangular groove, a clamping block, a T-block and a second spring. When the clamping block is pulled, the clamping block will move along the outer surface of the T-block and compress the second spring, thereby separating the clamping block and the rectangular groove. At this time, pulling the blade can make the blade move outward along the inner surface of the bottom end of the handle with the clamping plate and the connecting rod, so that the blade and the handle can be quickly disassembled, thereby improving the convenience of using the thoracolumbar disc disconnector. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1It is a schematic diagram of the structure of the present invention;

[0019] Figure 2 It is a cross-sectional structural schematic diagram of the front side of the present invention;

[0020] Figure 3 It is a schematic cross-sectional structural diagram of the fixing plate of the present invention;

[0021] Figure 4 It is a schematic cross-sectional structural diagram of the side of the present invention;

[0022] Figure 5 for Figure 1 A schematic diagram of the local enlarged structure at point A in the middle;

[0023] Figure 6 for Figure 2 A schematic diagram of the local enlarged structure at B in the middle;

[0024] Figure 7 for Figure 3 A schematic diagram of the local enlarged structure at C in the middle;

[0025] Figure 8 for Figure 4 A schematic diagram of the local enlarged structure at D in the middle;

[0026] Figure 9 for Figure 4 Schematic diagram of the local enlarged structure at point E in the middle.

[0027] In the figure: 1. handle; 2. anti-slip ring; 3. extension plate; 4. limit rod; 5. first gear; 6. tooth plate; 7. rectangular block; 8. round rod; 9. inclined rod; 10. movable block; 11. threaded rod; 12. hexagonal handle; 13. fixed plate; 14. round shaft; 15. knife handle; 16. second gear; 17. long rod; 18. short rod; 19. rotating frame; 20. paddle; 21. fixed block; 22. first spring; 23. blade; 24. visual lens; 25. card plate; 26. connecting rod; 27. rectangular groove; 28. card block; 29. ​​T-block; 30. second spring. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] like Figures 1 to 9As shown in the figure, the embodiment of the present invention provides a thoracolumbar disc dissector dedicated for total resection of thoracolumbar vertebrae, which includes a handle 1. An anti-slip ring 2 is fixedly sleeved on the outer surface of the handle 1. A extension plate 3 is fixedly installed in the middle of the bottom end of the handle 1. A limiting rod 4 is fixedly sleeved at the rear side of the middle end inside the extension plate 3. A first gear 5 is movably sleeved on the top of the outer surface of the limiting rod 4. Tooth plates 6 are respectively movably sleeved on the inner surfaces of the left and right ends of the extension plate 3. The number of the tooth plates 6 is two. The tops of the opposite surfaces of the two tooth plates 6 are respectively meshed and connected with the left and right sides of the outer surface of the first gear 5. Rectangular blocks 7 are respectively fixedly installed at the tops of the two tooth plates 6. The outer surface of the rectangular block 7 is movably sleeved with the inner surface of the top end of the extension plate 3. A round rod 8 is movably sleeved inside the rectangular block 7. The outer surface of the round rod 8 is fixedly sleeved with the inner surface of the top end of the extension plate 3. The top end of the rectangular block 7 is hinged with an inclined rod 9. The other end of the inclined rod 9 is hinged with a movable block 10. The outer surface of the movable block 10 is movably sleeved with the inner surface of the bottom end of the handle 1. A threaded rod 11 is threadedly sleeved inside the movable block 10. The outer surface of the threaded rod 11 is movably sleeved with the inner surface of the middle end of the handle 1. A hexagonal handle 12 is fixedly sleeved on the top of the outer surface of the threaded rod 11. The outer surface of the hexagonal handle 12 is movably sleeved with the inner surface of the handle 1.

[0030] Due to the existence of the anti-slip ring 2, it will be convenient to hold the handle 1. When the hexagonal handle 12 is rotated, the threaded rod 11 will rotate, so that the movable block 10 threadedly sleeved with the threaded rod 11 drives the inclined rod 9 to move along the inner surface of the bottom end of the handle 1. Furthermore, a thrust is generated on the rectangular block 7 by the other end of the inclined rod 9, pushing the rectangular block 7 to drive the two tooth plates 6 to move away from each other along the outer surface of the round rod 8, thereby unlocking the locking of the tooth plate 6 on the first gear 5. When the position of the first gear 5 is adjusted, rotate the hexagonal handle 12 again. After resetting the tooth plate 6, the position of the first gear 5 can be locked by means of the tooth plate 6. In this way, the adjustment of the position of the first gear 5 can be realized and fixed after the adjustment is completed, thus realizing the adjustment of the length of the dissector.

[0031] Wherein, a fixing plate 13 located outside the extension plate 3 is fixedly installed on the outer surface of the first gear 5. A round shaft 14 is movably sleeved inside the middle end of the fixing plate 13.

[0032] The inner surface of the fixing plate 13 and the outer surface of the round shaft 14 are both smooth, which ensures that the round shaft 14 will not get stuck when rotating along the inside of the middle end of the fixing plate 13.

[0033] Wherein, a knife handle 15 is fixedly sleeved on the left side of the outer surface of the round shaft 14. The outer surface of the knife handle 15 is movably connected with the outer surface of the fixing plate 13. A second gear 16 is fixedly sleeved on the right side of the outer surface of the round shaft 14. The outer surface of the second gear 16 is movably sleeved with the inner surface of the fixing plate 13.

[0034] When the handle 15 is rotated, the handle 15 will drive the second gear 16 to rotate together through the round shaft 14.

[0035] A long rod 17 is movably connected to the right side of the outer surface of the second gear 16. The right end of the long rod 17 penetrates through the fixing plate 13 and extends to the outside of the fixing plate 13. A short rod 18 is fixedly sleeved inside the right end of the long rod 17. A rotating frame 19 is movably sleeved on the outer surface of the short rod 18. The outer surface of the rotating frame 19 is movably connected to the outer surface of the fixing plate 13. A dial 20 is fixedly installed on the right side of the top of the rotating frame 19.

[0036] When the dial 20 is toggled, the rotating frame 19 will rotate around the short rod 18 as the axis, so that the long rod 17 will move towards the rotating frame 19 driven by the short rod 18, thereby unlocking the rotation position of the long rod 17 on the second gear 16.

[0037] A fixing block 21 is movably sleeved inside the right end of the long rod 17. The right end of the fixing block 21 is fixedly connected to the right inner wall of the fixing plate 13. A first spring 22 is fixedly installed at the left end of the fixing block 21. The other end of the first spring 22 is fixedly installed on the left inner wall of the long rod 17.

[0038] When the long rod 17 moves along the outer surface of the fixing block 21, the first spring 22 will be compressed, and under the restoring action of the first spring 22, the long rod 17 will be forced to return to its original position.

[0039] A blade 23 is fixedly installed at the bottom end of the handle 15. A visual lens 24 is fixedly sleeved inside the right end of the blade 23.

[0040] The right end of the blade 23 is blunt and has an inclined surface, so as to separate the paravertebral tissue and the ventral large blood vessels. The presence of the visual lens 24 can see the ventral large blood vessels of the vertebral body, thereby avoiding damaging the large blood vessels.

[0041] A clamping plate 25 is fixedly installed on the right side of the top of the blade 23. The outer surface of the clamping plate 25 is movably sleeved with the inner surface of the bottom end of the handle 15. A connecting rod 26 is fixedly installed at the left end of the clamping plate 25. The outer surface of the connecting rod 26 is movably sleeved with the inner surface of the bottom left end of the handle 15.

[0042] Due to the presence of the clamping plate 25 and the connecting rod 26, it will play a role in positioning the connection between the blade 23 and the handle 15.

[0043] A rectangular groove 27 is opened inside the connecting rod 26. A clamping block 28 is movably sleeved inside the rectangular groove 27. The right end of the clamping block 28 is movably connected to the left end of the handle 15.

[0044] The front side of the bottom end of the clamping block 28 is an inclined surface, and the position of the connecting rod 26 will be locked under the cooperation between the rectangular groove 27 and the clamping block 28 .

[0045] Among them, the rear end of the clamping block 28 is movably sleeved with a T-block 29, the right end of the T-block 29 is fixedly connected to the left end of the handle 15, and the front end of the T-block 29 is fixedly installed with a second spring 30, and the other end of the second spring 30 is fixedly connected to the inner surface of the clamping block 28.

[0046] Due to the existence of the T-shaped block 29 , the movement of the clamping block 28 will be limited, and the existence of the second spring 30 can enable the clamping block 28 to return to its original position after moving along the outer surface of the T-shaped block 29 .

[0047] Working principle and usage process:

[0048] First, when the length of the thoracolumbar disc disconnector is too short, the operator turns the hexagonal handle 12 to rotate the threaded rod 11, so that the movable block 10 threadedly sleeved on the outer surface of the threaded rod 11 moves along the inner surface of the bottom end of the handle 1 with the inclined rod 9, so that the other end of the inclined rod 9 generates a thrust on the rectangular block 7, pushing the rectangular block 7 with the two tooth plates 6 to move in opposite directions along the outer surface of the round rod 8 until the tooth plates 6 and the first gear 5 are completely separated. Then the operator pushes the knife handle 15, so that the knife handle 15 can move along the outer surface of the limit rod 4 with the first gear 5 through the fixed plate 13 until the knife handle 15 moves to a suitable position. Then the operator turns the hexagonal handle 12 in the opposite direction to restore the tooth plate 6 to its original position and lock the position of the first gear 5. In this way, the position of the knife handle 15 and the blade 23 can be adjusted and their positions can be fixed after the adjustment, thereby adjusting the length of the disconnector.

[0049] When the angle of the blade 23 needs to be adjusted, the operator turns the paddle 20 to make the rotating frame 19 rotate with the short rod 18 as the axis. At this time, as the rotating frame 19 rotates, the short rod 18 will move the long rod 17 toward the rotating frame 19 and compress the first spring 22. When the rotating frame 19 rotates ninety degrees, the long rod 17 will separate from the second gear 16. Then the operator turns the blade 23 to make the blade 23 rotate with the circular shaft 14, the handle 15, and the second gear 16 with the circular shaft 14 as the axis until the blade 23 rotates to a suitable angle. At this time, the operator turns the paddle 20 again to reset the rotating frame 19. Under the recovery action of the first spring 22, the long rod 17 can be re-embedded in the tooth groove on the outer surface of the second gear 16, thereby locking the rotation position of the second gear 16, the handle 15 and the blade 23, so as to achieve the adjustment of the angle and direction of the blade 23, thereby facilitating the cutting of the interplate.

[0050] When the blade 23 needs to be disassembled, the operator pulls the clamping block 28, causing the clamping block 28 to move along the outer surface of the T-shaped block 29 and compress the second spring 30, so that the clamping block 28 is separated from the rectangular groove 27, releasing the locking of the clamping block 28 on the connecting rod 26. Subsequently, the operator twitches the blade 23, and the blade 23 can be separated from the inside of the tool handle 15 with the clamping plate 25 and the connecting rod 26, thus realizing the rapid disassembly of the blade 23. At the same time, when installing the blade 23, since the right side of the bottom end of the clamping block 28 is beveled, the operator only needs to align the clamping plate 25 and the connecting rod 26 with the inner surface of the bottom end of the tool handle 15 and push the connecting rod 26 towards the tool handle 15, so that the connecting rod 26 presses the bevel surface of the clamping block 28, causing the clamping block 28 to move and compress the second spring 30. Under the restoring action of the second spring 30, when the clamping block 28 aligns with the rectangular groove 27, the clamping block 28 will return to its original position and be embedded in the rectangular groove 27. In this way, the connection and installation between the blade 23 and the tool handle 15 can be completed, thus improving the convenience of using the thoracolumbar discectomy forceps.

[0051] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device.

[0052] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A thoracolumbar discectomy device for total thoracic and lumbar corpectomy, comprising a handle (1), characterized in that: The outer surface of the handle (1) is fixedly sleeved with an anti-slip ring (2), the middle part of the bottom end of the handle (1) is fixedly installed with an extension plate (3), the rear side of the middle end of the extension plate (3) is fixedly sleeved with a limit rod (4), the top of the outer surface of the limit rod (4) is movably sleeved with a first gear (5), the inner surfaces of the left and right ends of the extension plate (3) are movably sleeved with tooth plates (6), the number of the tooth plates (6) is two, the tops of the opposite surfaces of the two tooth plates (6) are respectively meshed with the left and right sides of the outer surface of the first gear (5), the tops of the two tooth plates (6) are respectively fixedly installed with rectangular blocks (7), the outer surface of the rectangular block (7) and the inner surface of the top of the extension plate (3) are movably sleeved. The rectangular block (7) is movably sleeved with a round rod (8) inside, the outer surface of the round rod (8) is fixedly sleeved with the inner surface of the top end of the extension plate (3), the top end of the rectangular block (7) is hinged with an inclined rod (9), the other end of the inclined rod (9) is hinged with a movable block (10), the outer surface of the movable block (10) is movably sleeved with the inner surface of the bottom end of the handle (1), the inner thread of the movable block (10) is sleeved with a threaded rod (11), the outer surface of the threaded rod (11) is movably sleeved with the inner surface of the middle end of the handle (1), the top of the outer surface of the threaded rod (11) is fixedly sleeved with a hexagonal handle (12), the outer surface of the hexagonal handle (12) is movably sleeved with the inner surface of the handle (1).

2. The thoracolumbar disc disconnector for thoracic and lumbar corpectomy according to claim 1, characterized in that: A fixing plate (13) located outside the extension plate (3) is fixedly mounted on the outer surface of the first gear (5), and a circular shaft (14) is movably sleeved inside the middle end of the fixing plate (13).

3. The thoracolumbar disc disconnector for thoracic and lumbar corpectomy according to claim 2, characterized in that: A knife handle (15) is fixedly sleeved on the left side of the outer surface of the circular shaft (14), and the outer surface of the knife handle (15) is movably connected to the outer surface of the fixed plate (13). A second gear (16) is fixedly sleeved on the right side of the outer surface of the circular shaft (14), and the outer surface of the second gear (16) is movably sleeved to the inner surface of the fixed plate (13).

4. The thoracolumbar disc disconnector for thoracic and lumbar corpectomy according to claim 3, characterized in that: A long rod (17) is movably connected to the right side of the outer surface of the second gear (16); the right end of the long rod (17) penetrates the fixed plate (13) and extends to the outside of the fixed plate (13); a short rod (18) is fixedly sleeved inside the right end of the long rod (17); a rotating frame (19) is movably sleeved on the outer surface of the short rod (18); the outer surface of the rotating frame (19) is movably connected to the outer surface of the fixed plate (13); and a paddle (20) is fixedly installed on the right side of the top end of the rotating frame (19).

5. The thoracolumbar disc disconnector for thoracic and lumbar corpectomy according to claim 4, characterized in that: A fixing block (21) is movably sleeved at the right end of the interior of the long rod (17); the right end of the fixing block (21) is fixedly connected to the right inner wall of the fixing plate (13); a first spring (22) is fixedly mounted at the left end of the fixing block (21); the other end of the first spring (22) is fixedly mounted on the left inner wall of the long rod (17).

6. The thoracolumbar disc disconnector for thoracolumbar corpectomy according to claim 3, characterized in that: A blade (23) is fixedly mounted on the bottom end of the knife handle (15), and a visual lens (24) is fixedly sleeved inside the right end of the blade (23).

7. The thoracolumbar disc disconnector for thoracic and lumbar corpectomy according to claim 6, characterized in that: A clamping plate (25) is fixedly mounted on the right side of the top end of the blade (23), and the outer surface of the clamping plate (25) is movably sleeved with the inner surface of the bottom end of the handle (15). A connecting rod (26) is fixedly mounted on the left end of the clamping plate (25), and the outer surface of the connecting rod (26) is movably sleeved with the inner surface of the bottom left end of the handle (15).

8. The thoracolumbar disc disconnector for thoracic and lumbar corpectomy according to claim 7, characterized in that: A rectangular groove (27) is provided inside the connecting rod (26), a clamping block (28) is movably sleeved inside the rectangular groove (27), and the right end of the clamping block (28) is movably connected to the left end of the knife handle (15).

9. The thoracolumbar disc disconnector for thoracic and lumbar corpectomy according to claim 8, characterized in that: A T-block (29) is movably sleeved at the rear end of the clamping block (28); the right end of the T-block (29) is fixedly connected to the left end of the knife handle (15); a second spring (30) is fixedly installed at the front end of the T-block (29); the other end of the second spring (30) is fixedly connected to the inner surface of the clamping block (28).

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