Adjustable spine osteotomy device

Abstract

The adjustable spine osteotomy device comprises two power distribution boxes, the ends, close to each other, of the two power distribution boxes are rotationally connected, a second driving rod is rotationally installed at the bottom of one power distribution box, and a knife handle rod is arranged below the second driving rod; a first driving mechanism is jointly mounted in the two power distribution boxes, a mounting rod is mounted at the bottom of the knife handle rod, a plurality of blades are rotatably mounted at the bottom end of the mounting rod, a second driving mechanism is arranged at the bottom end of the knife handle rod, and a recycling mechanism for collecting part of bone debris is arranged on the outer wall of the knife handle rod. According to the bone grinding device, before the multiple blades are used, the second driving mechanism arranged at the bottom end of the knife handle rod can be used for driving the unfolding angles between the multiple blades to be gradually adjusted, the use requirements of bone grinding of different patients can be met, the workload of doctors is reduced, meanwhile, the operation risk of the patients can be reduced, and the operation time of the patients can be shortened.

Description

Technical Field

[0001] The invention relates to the technical field of medical instruments, and in particular to an adjustable spinal osteotomy device. Background Art

[0002] Kyphosis is a common clinical disease, commonly known as hunchback, hunchback, etc. The causes include congenital, degenerative, ankylosing spondylitis, old spinal tuberculosis kyphosis, etc. The cervical pedicle V-shaped osteotomy, referred to as PSO technology, is generally used. It is a closed osteotomy that achieves bony contact between the anterior and middle columns by removing the posterior lamina and pedicles of the spine, and then closing the back to achieve bony contact between the anterior and middle columns. The PSO technology not only shortens the structure of the posterior column of the spine, but also shortens the anterior and middle columns of the spine accordingly. On the one hand, shortening osteotomy can achieve bone contact between the anterior and middle columns, making the spine more stable, and also increasing the spinal fusion rate. On the other hand, if the osteotomy site is high, excessive shortening of the posterior column will inevitably cause flexion and wrinkling of the spinal cord, leading to serious neurological complications. Based on these characteristics, the PSO technology is mainly suitable for angular curvatures with low positions and obvious vertebral deformities, while for those rigid oblong curvatures, this method is not chosen for correction as much as possible.

[0003] In the prior art, when performing PSO osteotomy in clinical practice, there is no suitable surgical instrument. The operation is often performed based on the clinical evaluation of the patient before the operation and the use of bone knives to chisel the bone based on the doctor's experience during the operation. The surgical instruments used are also conventional instruments, which can easily cause nerve damage to the patient, making the operation risky. Moreover, the surgical instruments used for osteotomy cannot be adjusted in angle according to the patient's condition, which makes the patient's operation time longer and the doctor's workload increases accordingly. Summary of the invention

[0004] The purpose of the present invention is to solve the shortcomings of the prior art and to provide an adjustable spinal osteotomy device.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] An adjustable spinal osteotomy device comprises two power distribution boxes, the two power distribution boxes are rotatably connected at one end thereof which is close to each other, a second driving rod is rotatably mounted on the bottom of one of the power distribution boxes, a handle rod is arranged below the second driving rod, a first driving mechanism for driving the handle rod to rotate is commonly installed inside the two power distribution boxes, a mounting rod is mounted on the bottom of the handle rod, a plurality of blades are rotatably mounted on the bottom end of the mounting rod, a second driving mechanism for driving the plurality of blades to adjust their rotation angles is arranged on the bottom end of the handle rod, and a recovery mechanism for collecting some bone debris is arranged on the outer wall of the handle rod.

[0007] Optionally, the first driving mechanism includes a first rotating shaft and a second rotating shaft rotatably installed inside two power distribution boxes, one end of the first rotating shaft is inserted inside the second rotating shaft, and one of the power distribution boxes has two internal threads installed on it for limiting the rotation between the first rotating shaft and the second rotating shaft.

[0008] Optionally, a first bevel gear and a second bevel gear are respectively installed on the outer walls of the ends away from the first rotating shaft and the second rotating shaft, a power transmission cylinder is installed at the top of one of the power distribution boxes, a first driving rod is rotatably installed inside the power transmission cylinder, a rotating handle is installed at the top of the first driving rod, and the bottom end of the first driving rod extends to the interior of one of the power distribution boxes where a third bevel gear meshing with the first bevel gear is installed.

[0009] Optionally, a fourth bevel gear is installed at the top end of the second driving rod, the fourth bevel gear is meshed with the second bevel gear, and a first threaded connection portion is provided at the top end of the handle rod, and the first threaded connection portion is threadedly connected to the bottom end of the second driving rod.

[0010] Optionally, the second driving mechanism includes a movable sleeve slidably mounted on the outer wall of the mounting rod, a plurality of connecting rods are rotatably mounted on the outer wall of the movable sleeve, and ends of the plurality of connecting rods away from the movable sleeve are rotatably connected to corresponding blades.

[0011] Optionally, the bottom end of the tool handle rod is rotatably installed with two cams, and both ends of the rotating rod are provided with second threaded connection parts. The outer wall of the bottom end of the tool handle rod is installed with a fixing frame, and the two second threaded connection parts are respectively threaded through both sides of the fixing frame and are installed with fastening nuts.

[0012] Optionally, two vertical plates are symmetrically installed at the bottom end of the handle rod, through grooves are opened inside the two vertical plates, and two support rods sliding up and down in the through grooves are installed on the outer wall of the movable sleeve.

[0013] Optionally, a transverse plate is installed at the top end of the two support rods, and the top ends of the two transverse plates are respectively located and abut against the outer walls of the two cams.

[0014] Optionally, the recovery mechanism includes a transparent sleeve, two connecting sleeves are installed on the inner wall of the transparent sleeve, the handle rod is rotatably connected to the two connecting sleeves, and a protective sleeve is slidably installed on the outer wall of the transparent sleeve.

[0015] Optionally, the outer wall of the handle rod is provided with a spiral groove, the bottom end of the transparent sleeve is installed with a conical rubber sleeve, the top end of the rubber sleeve abuts against the outer wall of the handle rod, and two cover plates are rotatably installed on the top of the transparent sleeve.

[0016] The beneficial effects of the present invention are:

[0017] 1. In the present invention, before the multiple blades are used, the second driving mechanism arranged at the bottom end of the handle rod can be used to gradually adjust the deployment angles between the multiple blades, which can meet the bone grinding requirements of different patients, reduce the workload of doctors, and also reduce the surgical risks and operation time of patients.

[0018] 2. In the present invention, when the device is used to grind and remove the patient's bones, the two fastening bolts are manually screwed so that the two fastening bolts, which are close to each other, are moved and extended in a direction away from the second rotating shaft. The other power distribution box is manually rotated to drive the second driving rod and the handle rod thereunder to rotate and adjust, so that the inclination angles of the multiple blades in use can be freely controlled and adjusted according to needs, thereby improving the efficiency and safety of bone grinding.

[0019] 3. In the present invention, the protective cover arranged on the outer wall of the transparent cover can protect multiple blades during use, so that the multiple blades are not easily contacted with surrounding bones or bone nerves that do not need to be polished, thereby improving the safety during surgery. The protective cover can move up and down the outer wall of the transparent cover to adapt to the use requirements of multiple blades entering different depths inside the bone during operation.

[0020] 4. In the invention, a spiral groove is provided on the outer wall of the knife handle rod, and part of the bone debris generated by grinding bones with multiple blades can be transported upward along the groove, so that part of the bone debris can enter the interior of the transparent cover for collection, which is convenient for the subsequent unified collection of bone debris; after the operation on the patient is completed, the knife handle rod can be removed from the bottom end of the second driving rod, and the two cover plates can be rotated open to facilitate the bone debris collected inside the transparent cover to be poured out for reuse. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0022] Figure 1 This is a schematic diagram of the overall structure of an adjustable spinal osteotomy device proposed by the present invention;

[0023] Figure 2 for Figure 1 A schematic diagram of the structure of the two power distribution boxes and the interior of the transparent cover;

[0024] Figure 3 is a schematic structural diagram of the first driving mechanism in the present invention;

[0025] Figure 4 It is a structural schematic diagram of the knife handle rod in the present invention;

[0026] Figure 5 It is a schematic diagram of the structure of the present invention with two cover plates opened;

[0027] Figure 6 It is a schematic diagram of the structure of multiple blades in the present invention;

[0028] Figure 7 It is a structural schematic diagram of the moving sleeve and the horizontal plate in the present invention;

[0029] Figure 8 It is a schematic diagram of the structure in which two cams are separated from the tool handle rod in the present invention.

[0030] In the figure: 1. power distribution box; 2. power transmission cylinder; 3. first drive rod; 4. rotating handle; 5. fastening bolt; 6. second drive rod; 7. knife handle rod; 8. transparent cover; 9. protective cover; 10. blade; 11. third bevel gear; 12. first bevel gear; 13. second bevel gear; 14. fourth bevel gear; 15. first rotating shaft; 16. second rotating shaft; 17. groove; 18. first threaded connection; 19. rubber sleeve; 20. fixed frame; 21. cam; 22. movable sleeve; 23. connecting rod; 24. vertical plate; 25. support rod; 26. horizontal plate; 27. fastening nut; 28. second threaded connection; 29. ​​mounting rod; 30. through groove; 31. connecting sleeve; 32. cover plate. DETAILED DESCRIPTION

[0031] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than 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.

[0032] Reference Figure 1-Figure 8 An adjustable spinal osteotomy device includes two power distribution boxes 1, the two power distribution boxes 1 are connected at one end thereof, a second driving rod 6 is rotatably mounted at the bottom of one of the power distribution boxes 1, a handle rod 7 is arranged below the second driving rod 6, a first driving mechanism for driving the handle rod 7 to rotate is installed inside the two power distribution boxes 1, a mounting rod 29 is installed at the bottom of the handle rod 7, a plurality of blades 10 are rotatably mounted at the bottom end of the mounting rod 29, a second driving mechanism for driving the plurality of blades 10 to adjust the rotation angle is arranged at the bottom end of the handle rod 7, and a recovery mechanism for collecting part of the bone debris is arranged on the outer wall of the handle rod 7. In this embodiment, the plurality of blades 10 cooperate with each other to form a conical shape, so that after the handle rod 7 drives the plurality of blades 10 to rotate and grind and remove the bone, the notch of the bone is V-shaped, which can effectively improve the fusion rate of the patient's spine and make the spine more stable.

[0033] As a technical optimization solution of the present invention, the first driving mechanism includes a first rotating shaft 15 and a second rotating shaft 16 rotatably mounted inside two power distribution boxes 1, one end of the first rotating shaft 15 is inserted inside the second rotating shaft 16, and two fastening bolts 5 for limiting the rotation between the first rotating shaft 15 and the second rotating shaft 16 are installed on the internal thread of one of the power distribution boxes 1. The first rotating shaft 15 is inserted inside the second rotating shaft 16, so that the first rotating shaft 15 and the second rotating shaft 16 can rotate relative to each other, and the two fastening bolts 5 are screwed so that the ends of the two fastening bolts 5 that are close to each other extend to the inside of the second rotating shaft 16, so that the first rotating shaft 15 can be limited and fixed, so that the first rotating shaft 15 can drive the second rotating shaft 16 to rotate together while rotating.

[0034] As a technical optimization solution of the present invention, the outer wall of the end away from the first rotating shaft 15 and the second rotating shaft 16 is respectively installed with the first bevel gear 12 and the second bevel gear 13, the top of one of the power distribution boxes 1 is installed with the power transmission cylinder 2, the first driving rod 3 is rotatably installed inside the power transmission cylinder 2, the top of the first driving rod 3 is installed with the rotating handle 4, the bottom end of the first driving rod 3 extends to the inside of one of the power distribution boxes 1, and the third bevel gear 11 meshing with the first bevel gear 12 is installed. By rotating the rotating handle 4, the first driving rod 3 and the third bevel gear 11 are driven to rotate, so that the first bevel gear 12 meshing with the third bevel gear 11 drives the first rotating shaft 15 and the second rotating shaft 16 to rotate together.

[0035] As a technical optimization solution of the present invention, a fourth bevel gear 14 is installed at the top of the second driving rod 6, and the fourth bevel gear 14 is meshed with the second bevel gear 13. A first threaded connection portion 18 is provided at the top of the handle rod 7, and the first threaded connection portion 18 is threadedly connected with the bottom end of the second driving rod 6. When the second rotating shaft 16 drives the second bevel gear 13 to rotate, it can drive the fourth bevel gear 14 meshed with the second bevel gear 13 and the second driving rod 6 to rotate together, and drive the handle rod 7 below to rotate, so as to achieve the effect of controlling the rotation of the handle rod 7; and the handle rod 7 and the second driving rod 6 are threadedly connected through the first threaded connection portion 18, so that the handle rod 7 can be disassembled after use.

[0036] As a technical optimization solution of the present invention, the second driving mechanism includes a moving sleeve 22 slidably mounted on the outer wall of the mounting rod 29, and a plurality of connecting rods 23 are rotatably mounted on the outer wall of the moving sleeve 22, and the ends of the plurality of connecting rods 23 away from the moving sleeve 22 are respectively rotatably connected to the corresponding blades 10. The moving sleeve 22 slides up and down on the outer wall of the mounting rod 29, and can push the plurality of blades 10 to rotate toward or away from the mounting rod 29 with the help of the plurality of connecting rods 23, so as to achieve the effect of controlling the deployment angle of the plurality of blades 10.

[0037] As a technical optimization solution of the present invention, two cams 21 are installed at the bottom end of the handle rod 7 through the rotation of the rotating rod, and second threaded connection parts 28 are provided at both ends of the rotating rod. A fixing frame 20 is installed on the outer wall of the bottom end of the handle rod 7, and the two second threaded connection parts 28 are respectively threadedly installed with fastening nuts 27 through the two sides of the fixing frame 20. The two cams 21 can be driven to rotate together outside the handle rod 7 by rotating the rotating rod; after the cam 21 rotates to a suitable state, the rotating rod can be limited and fixed by means of two fastening nuts 27, thereby fixing the position of the cam 21.

[0038] As a technical optimization solution of the present invention, two vertical plates 24 are symmetrically installed at the bottom end of the handle rod 7, and through grooves 30 are opened inside the two vertical plates 24. Two support rods 25 that slide up and down in the through grooves 30 are installed on the outer wall of the movable sleeve 22. The two support rods 25 move up and down in the through grooves 30, which can provide a guiding effect for the up and down movement of the movable sleeve 22.

[0039] As a technical optimization solution of the present invention, a transverse plate 26 is installed at the top of the two support rods 25, and the tops of the two transverse plates 26 are respectively located at the outer walls of the two cams 21 and abut against each other. By rotating the rotating rod to drive the two cams 21 to rotate downward, the two transverse plates 26 below can be pushed, so that the two transverse plates 26 drive the two support rods 25 and the movable sleeve 22 to move downward together. After the rotating rod is limited and fixed by two fastening nuts 27, the two cams 21 can limit the upward movement of the transverse plates 26 to ensure that the angles of the multiple blades 10 will not change when in use.

[0040] As a technical optimization solution of the present invention, the recovery mechanism includes a transparent cover 8, two connecting covers 31 are installed on the inner wall of the transparent cover 8, the handle rod 7 is rotatably connected to the two connecting covers 31, and a protective cover 9 is slidably installed on the outer wall of the transparent cover 8. The protective cover 9 can protect the blade 10 when it is used around the blade 10, and the blade 10 is not easy to contact the surrounding bones or bone nerves that do not need to be polished, which can improve the safety during the operation; the protective cover 9 can move up and down on the surface of the transparent cover 8 to meet the use requirements of the blade 10 entering different depths inside the bone during operation.

[0041] As a technical optimization solution of the present invention, the outer wall of the handle rod 7 is provided with a spiral groove 17, the bottom end of the transparent cover 8 is installed with a conical rubber cover 19, the top end of the rubber cover 19 is in contact with the outer wall of the handle rod 7, and two cover plates 32 are rotatably installed on the top of the transparent cover 8. The handle rod 7 drives the multiple blades 10 to rotate, and the multiple blades 10 can grind and remove the vertebrae. Part of the bone debris generated by grinding can be transported upward along the spiral groove 17 on the outer wall of the handle rod 7, pushing the rubber cover 19, so that part of the bone debris can enter the interior of the transparent cover 8 for collection, which is convenient for the subsequent unified collection and reuse of the bone debris.

[0042] In the present invention, when the user uses the device, the first driving rod 3 and the third bevel gear 11 are driven to rotate by rotating the rotating handle 4, so that the first bevel gear 12 meshing with the third bevel gear 11 drives the first rotating shaft 15 and the second rotating shaft 16 to rotate together. When the second rotating shaft 16 drives the second bevel gear 13 to rotate, it can drive the fourth bevel gear 14 meshing with the second bevel gear 13 and the second driving rod 6 to rotate together, and drive the handle rod 7 below to rotate, so as to achieve the effect of controlling the handle rod 7 and the multiple blades 10 at the bottom to rotate synchronously, so that the rotating multiple blades 10 can grind and remove the bones to be ground, and the grinding gaps of the multiple blades 10 are V-shaped.

[0043] At the same time, before the multiple blades 10 are used, the two cams 21 can be driven to rotate downward by a certain angle by manually rotating the rotating rod, so that the two horizontal plates 26 below can be pushed, so that the two horizontal plates 26 drive the two supporting rods 25 and the movable sleeve 22 to move downward together. After the rotating rod is limited and fixed by two fastening nuts 27, the two cams 21 can limit the upward movement of the horizontal plate 26, and limit the upward movement of the movable sleeve 22 on the outer wall of the mounting rod 29, so as to ensure that the multiple blades 10 will not automatically rotate in the direction close to the mounting rod 29 when in use; and When controlling the rotating rod to drive the cam 21 to rotate downward and controlling the downward movement distance of the lower horizontal plate 26 and the movable sleeve 22, the rotating rod can be controlled to drive the two cams 21 to rotate downward at a smaller angle first, so as to drive the angle adjustment range between the multiple blades 10 to be smaller. After the multiple blades 10 grind a part of the bone, the blades 10 are taken out, and the rotating rod is continued to be controlled to drive the two cams 21 to rotate downward, so that the rotation angle of the two cams 21 increases, thereby driving the angle adjustment range between the multiple blades 10 to gradually increase. The bone can be grinded and adjusted multiple times to reach the final preset angle, which can meet the use requirements of different bone grinding.

[0044] During use, the two fastening bolts 5 are manually screwed so that the ends of the two fastening bolts 5 that are close to each other move and extend in a direction away from the second rotating shaft 16. At this time, the restriction between the first rotating shaft 15 and the second rotating shaft 16 is removed, and the other power distribution box 1 can be manually rotated to drive the second driving rod 6 and the handle rod 7 thereunder to rotate and adjust, so that the inclination angle of the multiple blades 10 during use can be freely controlled and adjusted according to needs, which can improve the efficiency and safety of bone grinding.

[0045] The protective cover 9 arranged on the outer wall of the transparent cover 8 can protect the multiple blades 10 during use, so that the multiple blades 10 are not easily contacted with the surrounding bones or bone nerves that do not need to be polished, which can improve the safety during the operation. The protective cover 9 can move up and down on the outer wall of the transparent cover 8 to adapt to the use requirements of the multiple blades 10 entering different depths inside the bone during operation.

[0046] Since the outer wall of the handle rod 7 is provided with a spiral groove 17, part of the bone debris generated by grinding bones with multiple blades 10 can be transported upward along the spiral groove 17 on the outer wall of the handle rod 7, and when transported to the position of the rubber sleeve 19, the rubber sleeve 19 can be pushed, so that part of the bone debris can enter the interior of the transparent sleeve 8 for collection, which is convenient for the subsequent unified collection of bone debris.

[0047] After the operation on the patient is completed, the handle rod 7 can be disassembled from the bottom end of the second driving rod 6, and the two cover plates 32 on the top of the transparent cover 8 can be rotated upward to open, so that the bone fragments collected in the transparent cover 8 can be poured out for reuse.

[0048] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. An adjustable spinal osteotomy device, comprising two power distribution boxes (1), characterized in that: The two power distribution boxes (1) are rotatably connected at one end thereof, a second driving rod (6) is rotatably mounted at the bottom of one of the power distribution boxes (1), a handle rod (7) is arranged below the second driving rod (6), a first driving mechanism for driving the handle rod (7) to rotate is commonly installed inside the two power distribution boxes (1), a mounting rod (29) is installed at the bottom of the handle rod (7), a plurality of blades (10) are rotatably mounted at the bottom end of the mounting rod (29), a second driving mechanism for driving the plurality of blades (10) to adjust their rotation angles is arranged at the bottom end of the handle rod (7), and a recovery mechanism for collecting some bone debris is arranged on the outer wall of the handle rod (7).

2. The adjustable spinal osteotomy device according to claim 1, characterized in that: The first driving mechanism comprises a first rotating shaft (15) and a second rotating shaft (16) rotatably mounted inside two power distribution boxes (1), one end of the first rotating shaft (15) being inserted inside the second rotating shaft (16), and two fastening bolts (5) for limiting the rotation between the first rotating shaft (15) and the second rotating shaft (16) being installed on the internal threads of one of the power distribution boxes (1).

3. The adjustable spinal osteotomy device according to claim 2, characterized in that: The first bevel gear (12) and the second bevel gear (13) are respectively mounted on the outer wall of the ends away from the first rotating shaft (15) and the second rotating shaft (16); a power transmission cylinder (2) is mounted on the top of one of the power distribution boxes (1); a first driving rod (3) is rotatably mounted inside the power transmission cylinder (2); a rotating handle (4) is mounted on the top of the first driving rod (3); and a third bevel gear (11) meshing with the first bevel gear (12) is mounted on the bottom end of the first driving rod (3) extending to the inside of one of the power distribution boxes (1).

4. The adjustable spinal osteotomy device according to claim 3, characterized in that: A fourth bevel gear (14) is installed at the top end of the second driving rod (6), and the fourth bevel gear (14) is meshed with the second bevel gear (13). A first threaded connection part (18) is provided at the top end of the handle rod (7), and the first threaded connection part (18) is threadedly connected to the bottom end of the second driving rod (6).

5. The adjustable spinal osteotomy device according to claim 1, characterized in that: The second driving mechanism comprises a movable sleeve (22) slidably mounted on the outer wall of the mounting rod (29); a plurality of connecting rods (23) are rotatably mounted on the outer wall of the movable sleeve (22); and one end of the plurality of connecting rods (23) away from the movable sleeve (22) is rotatably connected to the blades (10) corresponding thereto.

6. The adjustable spinal osteotomy device according to claim 5, characterized in that: The bottom end of the handle rod (7) is rotatably mounted with two cams (21), and both ends of the rotating rod are provided with second threaded connection parts (28). The outer wall of the bottom end of the handle rod (7) is mounted with a fixing frame (20), and the two second threaded connection parts (28) are respectively threadedly mounted with fastening nuts (27) passing through two sides of the fixing frame (20).

7. The adjustable spinal osteotomy device according to claim 6, characterized in that: Two vertical plates (24) are symmetrically mounted at the bottom end of the handle rod (7), and through grooves (30) are provided inside the two vertical plates (24). Two support rods (25) that slide up and down in the through grooves (30) are mounted on the outer wall of the movable sleeve (22).

8. The adjustable spinal osteotomy device according to claim 7, characterized in that: A transverse plate (26) is installed at the top end of the two support rods (25), and the top ends of the two transverse plates (26) are respectively located on the outer walls of the two cams (21) and abut against each other.

9. The adjustable spinal osteotomy device according to claim 1, characterized in that: The recovery mechanism comprises a transparent sleeve (8), the inner wall of the transparent sleeve (8) is equipped with two connecting sleeves (31), the handle rod (7) is rotatably connected to the two connecting sleeves (31), and the outer wall of the transparent sleeve (8) is slidably equipped with a protective sleeve (9).

10. The adjustable spinal osteotomy device according to claim 9, characterized in that: The outer wall of the knife handle rod (7) is provided with a spiral groove (17); the bottom end of the transparent sleeve (8) is provided with a conical rubber sleeve (19); the top end of the rubber sleeve (19) abuts against the outer wall of the knife handle rod (7); and two cover plates (32) are rotatably installed on the top of the transparent sleeve (8).

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