Anti-fracture nail extractor

Abstract

The invention relates to the technical field of nail taking devices, and discloses an anti-fracture nail taking device which comprises a handle and a sleeve arranged at the bottom end of the handle, a bit is detachably mounted on the sleeve, and the anti-fracture nail taking device further comprises a rotating shaft fixedly mounted in the center of the top of the sleeve and rotationally connected with the handle; the floating ring is movably arranged between the bottom end of the handle and the top of the sleeve and is downwards supported by the elastic supporting mechanism; limiting teeth are evenly arranged on the edge side of the bottom of the floating ring, pushing teeth are evenly arranged on the edge side of the top of the sleeve, and the limiting teeth are meshed with the pushing teeth. According to the anti-fracture screw extractor, when the torque is overloaded, the floating ring can provide buffering, the situation that the screwdriver bit continuously applies overlarge torque is avoided, then the internal stress can be gradually released in the screwing-out process of a screw, stress concentration is reduced, and the risk of screw fracture is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of nail removers, in particular to a fracture-resistant nail remover. Background Art

[0002] In orthopedics, implanted screws are used to fix fracture sites to promote fracture healing. When the fracture healing is complete or the patient feels uncomfortable due to the implantation of screws, the screws need to be removed in time. However, during the removal of screws, some problems often occur: Screws that have been implanted for a long time may have stress concentration while being subjected to biomechanical effects, especially in the head and middle areas. In this case, if excessive torque is applied directly when unscrewing the screw, it may cause the screw to break, increasing the difficulty of the operation. In addition, if the screw has been implanted for a long time, the bone tissue may have partially wrapped around the screw thread, causing the screw to be tightly combined with the bone structure. In this case, if the screw is forcibly unscrewed, the bone tissue is likely to reversely lock the screw, making it more difficult to unscrew the screw, and even causing the screw to break.

[0003] In the prior art, it is not easy to avoid the above problems when using nail removal tools such as manual screwdrivers, electric screwdrivers, and impact nail removers, which results in the screws being easily broken during the nail removal process. Summary of the invention

[0004] 1. Technical issues to be resolved In view of the deficiencies in the prior art, the present invention provides an anti-fracture nail remover, which has the advantage of preventing screws from breaking.

[0005] (II) Technical solution In order to achieve the above-mentioned purpose of preventing screw breakage, the present invention provides the following technical solution: an anti-breakage nail remover, comprising a handle and a sleeve arranged at the bottom end of the handle, a screwdriver bit being detachably mounted on the sleeve, and further comprising: The rotating shaft is fixedly mounted at the center of the top of the sleeve and is rotatably connected to the handle; A floating ring is movably disposed between the bottom end of the handle and the top of the sleeve and is supported downward by an elastic support mechanism; The sides of the bottom of the floating ring are evenly provided with limiting teeth, and the sides of the top of the sleeve are evenly provided with pushing teeth, and the limiting teeth are engaged with the pushing teeth.

[0006] As a preferred technical solution of the present invention, a shaft groove for allowing the rotating shaft to pass through is formed at the center of the floating ring.

[0007] As a preferred technical solution of the present invention, the elastic support mechanism includes a top rod, an inner plate, an inner cavity and a spring; A push rod is fixedly installed on the side of the top of the floating ring, and an inner plate is fixedly connected to the top of the push rod. The inner plate is movably arranged in an inner cavity opened inside the handle and is supported downward by a spring.

[0008] As a preferred technical solution of the present invention, the inner plate is a piston, and an oil hole is formed through it; The inner cavity is filled with damping oil.

[0009] As a preferred technical solution of the present invention, the oil hole is a tapered hole with a larger top end and a smaller bottom end.

[0010] As a preferred technical solution of the present invention, a vertical hole is opened at the center of the bottom end of the handle, and the rotating shaft is rotatably installed in the vertical hole through a fixed bearing.

[0011] As a preferred technical solution of the present invention, a friction disc is fixedly mounted on the top end of the rotating shaft, and the friction disc is rotatably arranged in a transmission cavity opened inside the handle; The top of the piston is fixedly connected with an annular friction plate via an L-shaped rod, and the annular friction plate is movably sleeved on the rotating shaft; A reverse transmission mechanism is also provided, and when the annular friction plate rotates, the friction disc can be driven to rotate in the reverse direction through the reverse transmission mechanism.

[0012] As a preferred technical solution of the present invention, the reverse transmission mechanism comprises a vertical transmission disc 1 and a transmission disc 2, and the transmission disc 1 and the transmission disc 2 are both rotatably installed in the transmission cavity through a transverse axis; The top of the transmission disc 1 contacts the side of the bottom of the friction disc, and the bottom contacts the transmission disc 2. The bottom of the transmission disc 2 can contact the annular friction plate.

[0013] As a preferred technical solution of the present invention, when the annular friction plate moves upward, it can contact with the transmission disc two.

[0014] (III) Beneficial effects Compared with the prior art, the present invention provides a nail remover that is anti-fracture and has the following beneficial effects: 1. When the torque is overloaded, the floating ring of the anti-fracture nail remover can provide a buffer to prevent the screwdriver from continuously applying excessive torque, thereby gradually releasing the internal stress of the screw during the unscrewing process, reducing stress concentration and the risk of screw breakage.

[0015] 2. The anti-fracture nail remover can automatically tighten the screw bit when the torque is overloaded, so that the bone ingrowth tissue can be gradually loosened during the screw removal process, avoiding the reverse locking of the screw by the bone tissue, thereby improving the success rate of screw removal and further reducing the risk of screw breakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 is an enlarged schematic diagram of the handle portion of the present invention; Figure 3 is a cross-sectional view of the handle portion of the present invention; Figure 4 It is an enlarged schematic diagram of the floating ring part of the present invention; Figure 5 For the present invention Figure 3 The enlarged schematic diagram of point A in the middle; Figure 6 It is an enlarged schematic diagram of the friction disc part of the present invention.

[0017] In the figure: 1. handle; 2. sleeve; 3. bit; 4. rotating shaft; 5. fixed bearing; 6. floating ring; 7. shaft groove; 8. limit tooth; 9. push tooth; 10. push rod; 11. piston; 12. inner cavity; 13. spring; 14. oil hole; 15. L-shaped rod; 16. annular friction plate; 17. friction disc; 18. transmission disc 1; 19. transmission disc 2; 20. transmission cavity. DETAILED DESCRIPTION

[0018] 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.

[0019] Embodiment 1: See also Figure 1-Figure 5 A fracture-proof nail remover comprises a handle 1 and a sleeve 2 arranged at the bottom end of the handle 1, a screwdriver bit 3 is detachably mounted on the sleeve 2, and a connection method between the screwdriver bit 3 and the sleeve 2 can be referred to the prior art by those skilled in the art, which will not be described in detail here.

[0020] like Figure 3 As shown, a rotating shaft 4 is fixedly installed at the center of the top of the sleeve 2, and the rotating shaft 4 is rotatably connected to the handle 1. Specifically, a vertical hole is opened at the center of the bottom end of the handle 1, and the rotating shaft 4 is rotatably installed in the vertical hole through a fixed bearing 5, so that the handle 1 and the sleeve 2 can rotate independently of each other; In the present invention, a floating ring 6 is movably arranged between the bottom end of the handle 1 and the top of the sleeve 2. Figure 4As shown, a shaft groove 7 for the rotating shaft 4 to pass through is formed at the center of the floating ring 6, and limiting teeth 8 are evenly arranged on the sides of the bottom of the floating ring 6, and pushing teeth 9 are evenly arranged on the sides of the top of the sleeve 2. The limiting teeth 8 are engaged with the pushing teeth 9. In addition, the floating ring 6 is supported downward by an elastic support mechanism; During normal operation, the floating ring 6 is supported downward by the elastic support mechanism, the limiting teeth 8 are engaged with the pushing teeth 9, and when the handle 1 is turned, the sleeve 2 and the bit 3 are also turned, so that the screw can be loosened; When the torque is too large, the floating ring 6 will be forced to move upward and compress the elastic support mechanism due to excessive force. At this time, the limit teeth 8 and the push teeth 9 can be temporarily separated to release part of the torque; Therefore, when the torque is overloaded, the floating ring 6 can provide a buffer to prevent the bit 3 from continuously applying excessive torque, thereby gradually releasing the internal stress of the screw during the unscrewing process, reducing stress concentration and lowering the risk of screw breakage.

[0021] In this embodiment, the elastic support mechanism includes a top rod 10, an inner plate, an inner cavity 12 and a spring 13. Specifically, Figure 5 As shown, a push rod 10 is fixedly installed on the side of the top of the floating ring 6, and the top of the push rod 10 is fixedly connected to an inner plate. The inner plate is movably arranged in an inner cavity 12 opened inside the handle 1, and is supported downward by a spring 13. Therefore, the floating ring 6 is supported downward by the spring 13 so that the limiting tooth 8 and the pushing tooth 9 are engaged. When the torque is overloaded, the spring 13 is also compressed to achieve a torque buffering effect.

[0022] Furthermore, the inner plate can be set as the piston 11, and an oil hole 14 can be opened through it. In addition, the inner cavity 12 is filled with damping oil. In this way, the flow of damping oil in the oil hole 14 can make the piston 11 (i.e., the inner plate) move downward more slowly, avoiding the limit tooth 8 and the push tooth 9 from re-engaging just after separation, so that the handle 1 can maintain idling for a period of time.

[0023] like Figure 5 As shown, the oil hole 14 is a tapered hole with a larger top end and a smaller bottom end, so that the piston 11 moves upward more easily and moves downward more slowly, which is more conducive to maintaining the idling of the handle 1.

[0024] Embodiment 2: See also Figure 2 and Figure 6On the basis of the first embodiment, in this embodiment, when the handle 1 idles due to torque overload, the sleeve 2 and the screw bit 3 can automatically tighten the screw for a short distance, and adopt a loosening-tightening-loosening method to make the thread move back and forth slightly, which can gradually loosen the bone tissue surrounding the screw, making the final screwing resistance smaller, so that the bone ingrowth tissue can be gradually loosened during the screwing process, avoiding the reverse locking of the screw by the bone tissue, improving the success rate of screwing out, and further reducing the risk of screw breakage.

[0025] For details, please refer to Figure 3 A friction disc 17 is fixedly mounted on the top of the rotating shaft 4. The friction disc 17 is rotatably arranged in a transmission chamber 20 opened inside the handle 1. In addition, an annular friction plate 16 is fixedly connected to the top of the piston 11 through an L-shaped rod 15. The annular friction plate 16 is movably sleeved on the rotating shaft 4. When the annular friction plate 16 rotates, the friction disc 17 can be driven to rotate in the reverse direction through the reverse transmission mechanism. In this embodiment, the reverse transmission mechanism includes a vertical transmission disc 18 and a transmission disc 2 19, both of which are installed in the transmission cavity 20 by rotating about a horizontal axis, the top of the transmission disc 18 contacts the side of the bottom of the friction disc 17, and the bottom contacts the transmission disc 2 19, and the bottom of the transmission disc 2 19 can contact the annular friction plate 16. Specifically, when the annular friction plate 16 moves upward, it can contact the transmission disc 2 19; Therefore, when the torque overload causes the piston 11 to move upward, the piston 11 will also drive the annular friction plate 16 to move upward through the L-shaped rod 15, so that it contacts the second transmission disc 19. After the annular friction plate 16 contacts the second transmission disc 19, when the handle 1 is idle again, the transmission of the first transmission disc 18 and the second transmission disc 19 can make the friction disc 17 rotate in the opposite direction, thereby achieving "re-tightening". The realization of the re-tightening also utilizes the slow downward movement of the piston 11 due to the damping oil, so that the annular friction plate 16 can effectively contact with the transmission plate 2 19 within a time window, rather than "touching and separating".

[0026] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An anti-fracture nail remover, comprising a handle (1) and a sleeve (2) arranged at the bottom end of the handle (1), wherein a screwdriver bit (3) is detachably mounted on the sleeve (2), characterized in that: Also includes: A rotating shaft (4) is fixedly mounted at the center of the top of the sleeve (2) and is rotatably connected to the handle (1); A floating ring (6) is movably disposed between the bottom end of the handle (1) and the top of the sleeve (2), and is supported downward by an elastic support mechanism; Limiting teeth (8) are evenly arranged on the sides of the bottom of the floating ring (6), and pushing teeth (9) are evenly arranged on the sides of the top of the sleeve (2), and the limiting teeth (8) are engaged with the pushing teeth (9).

2. The anti-fracture nail remover according to claim 1, characterized in that: A shaft groove (7) for allowing the rotating shaft (4) to pass through is formed at the center of the floating ring (6).

3. The anti-fracture nail remover according to claim 1, characterized in that: The elastic support mechanism comprises a push rod (10), an inner plate, an inner cavity (12) and a spring (13); A push rod (10) is fixedly mounted on the side of the top of the floating ring (6), and an inner plate is fixedly connected to the top of the push rod (10). The inner plate is movably arranged in an inner cavity (12) opened inside the handle (1) and is supported downward by a spring (13).

4. The anti-fracture nail remover according to claim 3, characterized in that: The inner plate is a piston (11) and has an oil hole (14) extending therethrough; The inner cavity (12) is filled with damping oil.

5. The anti-fracture nail remover according to claim 4, characterized in that: The oil hole (14) is a tapered hole with a larger top end and a smaller bottom end.

6. The anti-fracture nail remover according to claim 4 or 5, characterized in that: A vertical hole is provided at the center of the bottom end of the handle (1), and the rotating shaft (4) is rotatably mounted in the vertical hole via a fixed bearing (5).

7. The anti-fracture nail remover according to claim 6, characterized in that: A friction disc (17) is fixedly mounted on the top end of the rotating shaft (4), and the friction disc (17) is rotatably disposed in a transmission cavity (20) provided inside the handle (1); The top of the piston (11) is fixedly connected to an annular friction plate (16) via an L-shaped rod (15), and the annular friction plate (16) is movably sleeved on the rotating shaft (4); A reverse transmission mechanism is also provided, and when the annular friction plate (16) rotates, the friction disc (17) can be driven to rotate in the reverse direction through the reverse transmission mechanism.

8. The anti-fracture nail remover according to claim 7, characterized in that: The reverse transmission mechanism comprises a vertical transmission disc 1 (18) and a transmission disc 2 (19), wherein the transmission disc 1 (18) and the transmission disc 2 (19) are both rotatably mounted in the transmission cavity (20) via a transverse axis; The top of the transmission disc 1 (18) contacts the side of the bottom of the friction disc (17), and the bottom contacts the transmission disc 2 (19). The bottom of the transmission disc 2 (19) can contact the annular friction plate (16).

9. The anti-fracture nail remover according to claim 8, characterized in that: When the annular friction plate (16) moves upward, it can contact the second transmission plate (19).

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