CN110680485A - Locking combined compression screw - Google Patents

Abstract

The invention discloses a locking combined compression screw, which comprises a component A, a component B and a component C, wherein the surface of the component A is provided with a first external thread 1 and a second external thread 2, one end of the component A, which is close to the second external thread 2, is of a hollow structure, and a first internal thread 3 is arranged in the hollow structure; the component B is a cylindrical hollow structure provided with a second internal thread 4 and a third internal thread, and a pressurizing structure is arranged at the end part of the component B close to the third internal thread 5; the component C comprises a third external thread 6 and a fourth external thread 7. Compared with the prior art, the locking combination compression screw provided by the invention can reduce the incidence rate of internal fixation failure, delayed healing of fracture deformity and bone nonunion.

Description

Locking combined compression screw

Technical Field

The invention relates to a medical fracture fixing device, in particular to an internal fixing system applied to compression fixation among fracture blocks.

Background

For treating fractures needing operations, such as dentate process fractures, intra-articular fractures and the like, fracture reduction, pressurization and strong fixation are realized through a lag screw; the invention relates to a combined compression screw which is an unlocked two-component lag screw, and the working principle is as follows: in the process of pressurizing the combined pressurizing screw, one component of the screw rotates around the other component, so that the length of the screw is shortened, the fracture seam is closed, the thread is lifted, pressurizing force is generated among fracture blocks, and the structural stability of the fracture part is reconstructed; if the external force acting on the fracture block is larger than the friction force maintaining the stable structure of the fracture part, the fracture block rotates, the two components of the compression combined screw may rotate, the length of the screw is lengthened, and in this state, the compression effect of the combined compression screw is lost, so that the fracture deformity is delayed to heal, and even the bone is not healed.

Disclosure of Invention

The invention aims to: overcomes the defects in the prior art, solves the problems in the prior art, and provides a combined compression screw capable of being locked, thereby reducing the incidence of internal fixation failure, delayed union of fracture deformity and bone nonunion.

The technical scheme of the invention is as follows: a locking combination compression screw: comprises a component A, a component B and a component C,

a firstexternal thread 1 and a secondexternal thread 2 are arranged on the surface of the component A, one end of the component A close to the secondexternal thread 2 is of a hollow structure, and a first internal thread 3 is arranged in the hollow structure;

the component B is of a hollow structure, a secondinternal thread 4 and a thirdinternal thread 5 are arranged in the hollow structure of the component B, and the secondinternal thread 4 is matched with the secondexternal thread 2 of the component A so as to realize the connection of the component A and the component B; the tail end of the component B close to the thirdinternal thread 5 is provided with a pressurizing structure;

the component C is formed by connecting two cylinders with different diameters, and the axes of the two cylinders are on the same straight line; the cylinder surface that the diameter is little is provided with thirdexternal screw thread 6, and the cylinder surface that the diameter is big is provided with fourth external screw thread 7, thirdexternal screw thread 6 with subassembly A's first internal thread 3 phase-matches to realize being connected of subassembly C and subassembly A, fourth external screw thread 7 with subassembly B's thirdinternal thread 5 phase-matches to realize being connected of subassembly C and subassembly A.

As a preferable aspect of the locking combination compression screw of the present invention:

the secondexternal thread 2 of the component A and the secondinternal thread 4 of the component B are a first pair of threads, the thirdexternal thread 6 of the component C and the first internal thread 3 of the component A are a second pair of threads, and the fourth external thread 7 of the component C and the thirdinternal thread 5 of the component B are a third pair of threads; the thread pitch and the thread rotation direction of the second pair of threads and the third pair of threads are the same, and the thread pitch and/or the thread rotation direction of the first pair of threads are different from those of the second pair of threads and the third pair of threads.

As a preferable aspect of the locking combination compression screw of the present invention:

the component A and the component C can be hollow, and the hollow part can be inserted with a guide pin, so that the operation accuracy is improved.

As a preferable aspect of the locking combination compression screw of the present invention:

the pressurizing structure of the component B is an expanded hemispherical structure, and the cross section knot of the pressurizing structure is the largest part of the component B; the surface of the pressurizing structure of the component B is provided with a fifthexternal thread 8, and the fifthexternal thread 8 can be screwed into a bone fracture plate or a bone, so that the stability of the screw-bone structure is improved.

As a preferable aspect of the locking combination compression screw of the present invention:

the tail end of the hollow structure of the component A is provided with a hollow prismatic structure 11, and a screwdriver matched with the component A can control the component A through the hollow prismatic structure 11;

a firsthollow cross structure 13 is arranged in the pressurizing structure of the component B, and a screwdriver matched with the component B can control the component B through the firsthollow cross structure 13;

the tail end of the fourth external thread 7 of the component C is provided with afirst cross structure 15, and a screwdriver matched with the component C can operate and control the component C through thefirst cross structure 15.

As a preferable aspect of the locking combination compression screw of the present invention:

a first scale mark 9 is arranged between the firstexternal thread 1 and the secondexternal thread 2 of the component A, and the first scale mark 9 is a scale mark for indicating that the component B is assembled on the component A, namely when the component B is rotated on the secondexternal thread 2 of the component A through the secondinternal thread 4 thereof, the tail end of the component B is flush with the first scale mark 9.

As a preferable aspect of the locking combination compression screw of the present invention:

the outer surface of the component B is provided with asecond graduation line 10, and thesecond graduation line 10 is a graduation line indicating the depth of the component B implanted into the bone, namely: when the assembled component A and component B are implanted into the bone, the second graduation marks 10 on the component B are flush with the surface of the bone.

As a preferable aspect of the locking combination compression screw of the present invention:

the surface of the component A and/or the component B is formed with an uneven structure which can be filled with a medicament beneficial to bone healing.

As a preferable aspect of the locking combination compression screw of the present invention:

the surface of the component A and/or the component B is subjected to sand blasting or porous and hydroxyapatite protruding treatment to form micropores, so that the bone can grow in the micropores, and the stability of the bone-internal fixation structure is improved.

As a preferable aspect of the locking combination compression screw of the present invention:

a screwdriver matched with the locking combination compression screw, which comprises a screwdriver E, a screwdriver F and a screwdriver G,

one end of the driver E is aprismatic structure 12, and theprismatic structure 12 is matched with the hollow prismatic structure 11 of the component A, so that the driver E can operate the component A;

one end of the screwdriver F is a second hollow cross structure 14, and the second hollow cross structure 14 is matched with the firsthollow cross structure 13 of the component B, so that the screwdriver F can operate the component B;

one end of the screwdriver G is asecond cross-shaped structure 16, and thesecond cross-shaped structure 16 is matched with thefirst cross-shaped structure 15 of the component C, so that the screwdriver G can operate the component C;

the screwdriver F is a hollow structure, after the screwdriver F is connected with the component B through the second hollow cross structure 14 and the firsthollow cross structure 13, the outer diameter of the columnar structure of the screwdriver E and the screwdriver G is smaller than or equal to the inner diameter of the hollow structure of the screwdriver F, and the screwdriver E and the screwdriver G can respectively penetrate through the hollow structure of the screwdriver F to realize the operation and control of the component A and the component C.

A preferred version of the foregoing driver: the screwdriver E and the screwdriver F are respectively provided with afirst locking structure 17 and a second locking structure 18 which are matched with each other, the second locking structure 18 on the screwdriver F is pushed, and the locking between the screwdriver E and the screwdriver F is completed; the second locking structure 18 on the driver F is pushed in reverse to release the locking between the driver E and the driver F.

The invention has at least the following advantages:

1. the locking combined compression screw has simple and reliable screw compression and locking structure, convenient operation and mild learning curve, and is convenient for doctors to accumulate experience and improve the accuracy of the operation: the secondexternal thread 2 of the component A and the secondinternal thread 4 of the component B are a first pair of threads, the component B rotates by taking the component A as an axis, the length of a screw is shortened, thefirst thread 1 of the component A is pulled, a fracture seam is closed, cancellous bones around thefirst thread 1 are compressed, a pressurizing structure of the component B is combined to act on bones/gaskets/bone fracture plates, pressurizing force is generated, and fracture is pressurized and fixed; the thirdexternal thread 6 of the component C and the first internal thread 3 of the component A are a second pair of threads, the fourth external thread 7 of the component C and the thirdinternal thread 5 of the component B are a third pair of threads, and the thread pitches and the thread rotating directions of the second pair of threads and the third pair of threads are the same, so that the component C can be connected with the component A and the component B at the same time; when the assembly A, the assembly B and the assembly C are assembled, the requirement that the assembly A and the assembly B rotate relatively is that the first pair of threads and the second and third pairs of threads rotate synchronously, but the thread pitch and/or the thread rotating direction of the first pair of threads and the second and third pairs of threads are different, and the requirement that the assembly A and the assembly B rotate relatively does not exist, so that the assembly A and the assembly B are in a locking state after the assembly A, the assembly B and the assembly C are assembled. Therefore, the postoperative rehabilitation is very beneficial to postoperative recovery, and the falling, loosening and the like of the screw cannot be caused even if a patient performs certain movement.

There is an embodiment according to the present invention, namely: the first pair of threads and the second and third pairs of threads have the same pitch and thread rotation direction, and locking between the assemblies is achieved by tightening the second and third pairs of threads, which is not as good as locking with different pitches and/or thread rotation directions.

2. After the locking combined compression screw is implanted into a body, all components of the screw are in a locking state, the structural stability of the locking combined compression screw can be improved, when external force acts on one fracture block and the fracture block is required to rotate relative to the other fracture block, the combined compression screw in the locking state controls the other fracture block to synchronously rotate with the fracture block acted by the external force, and therefore the incidence rate of fracture internal fixation failure, delayed healing of fracture deformity and bone nonunion is reduced.

3. The surface of the component A and/or the component B of the locking combined compression screw is provided with the uneven structure, and the uneven structure can be filled with medicines beneficial to bone healing, so that the healing rate of fracture is improved; the surface of the component A and/or the component B is subjected to sand blasting or porous and hydroxyapatite protruding treatment to form micropores, so that bone ingrowth is facilitated, the stability of a bone-internal fixation structure is improved, and the incidence rate of internal fixation failure is reduced.

Drawings

FIG. 1 is a schematic structural view of a locking combination compression screw assembly A of the present invention;

FIG. 2 is a schematic end view of the hollow structure of module A;

FIG. 3 is a schematic structural view of a locking combination compression screw assembly B of the present invention;

FIG. 4 is a schematic end view of the compression configuration of assembly B;

FIG. 5 is a schematic view of the combination of component A and component B;

FIG. 6 is a schematic structural view of a locking combination compression screw assembly C of the present invention;

FIG. 7 is a schematic end view of the assembly C near one end of the fourth external thread 7;

FIG. 8 is a schematic structural view of a combination of component A, component B and component C;

FIG. 9 is a schematic structural view of a driver E for locking a combination compression screw according to the present invention;

fig. 10 is a schematic structural view of a driver F for locking a combination compression screw according to the present invention;

fig. 11 is a structural schematic view of a combination of a driver E and a driver F;

fig. 12 is a schematic view of the combination of driver E and driver F in accordance with the present invention mated with combination a and assembly B;

fig. 13 is a schematic structural view of a driver G for locking a combination compression screw according to the present invention;

fig. 14 is a structural schematic view of a combination of a driver G and a driver F;

fig. 15 is a schematic structural view of the operation assembly C mated with the assembly a and the assembly B (the assembly a and the assembly B have completed connection) after the combination of the driver G and the driver F;

fig. 16 is a schematic view of a locking combination compression screw of the present invention implanted in a bone.

Detailed Description

The technical solution of the present invention is described in detail below with reference to the accompanyingdrawings 1 to 16 and embodiments, in which: 1. a first external thread; 2. a second external thread; 3. a first internal thread; 4. a second internal thread; 5. a third internal thread; 6. a third external thread; 7. a fourth external thread; 8. a fifth external thread; 9. a first scale mark; 10. a second scale mark; 11. a hollow prismatic structure; 12. a prismatic structure; 13. a first hollow cross structure; 14. a second hollow cross structure; 15. a first cross structure; 16. a second cross-shaped structure; 17. a first locking structure; 18. a second locking structure.

As shown in fig. 1 to 16, the present invention discloses a locking combination compression screw comprising a component a, a component B and a component C.

Referring to fig. 1 and 2, the component a has a cylindrical structure, a firstexternal thread 1 is disposed on a surface of one end, a hollow structure is disposed on the other end, a secondexternal thread 2 is disposed on the surface, a first internal thread 3 is disposed in the hollow structure, and a hollow prismatic structure 11 is disposed at a tail end of the hollow structure.

Referring to fig. 3 and 4, the component B is a cylindrical structure with a hollow interior, a secondinternal thread 4 and a thirdinternal thread 5 are arranged in the hollow structure of the component B, a pressurizing structure is arranged at one end of the component B close to the thirdinternal thread 5, the pressurizing structure is an expanded hemispherical structure, a fifthexternal thread 8 is arranged on the surface of the pressurizing structure of the component B, and a firsthollow cross structure 13 is arranged in the pressurizing structure.

Referring to fig. 6 and 7, the assembly C is formed by connecting two cylinders with different diameters, and the axes of the two cylinders are on the same straight line; the surface of the cylinder with the small diameter is provided with a thirdexternal thread 6, the surface of the cylinder with the large diameter is provided with a fourth external thread 7, and the tail end of the fourth external thread 7 is provided with afirst cross structure 15.

Fig. 8 is a schematic structural diagram of the combination of the component a, the component B and the component C, and the combination process may be: subassembly A and subassembly B are connected with secondinternal thread 4 through secondexternal screw thread 2, then subassembly C is provided with the one end of thirdexternal screw thread 6 and passes the inside hollow structure of subassembly B, and stretch into the inside hollow structure of subassembly A, next the rotation subassembly C, thirdexternal screw thread 6 and first internal thread 3 match each other, realize that subassembly C and subassembly A are connected, and meanwhile, fourth external screw thread 7 and thirdinternal thread 5 match each other, realize that subassembly C and subassembly B are connected.

Fig. 9 is a schematic structural diagram of a driver E, the driver E is divided into a rod part and a handle, the end of the rod part is provided with aprismatic structure 12 and afirst locking structure 17, and theprismatic structure 12 is matched with the hollow prismatic structure of the component a to realize the operation of the driver E on the component a.

Fig. 10 is a structural schematic diagram of a screwdriver F, wherein the screwdriver F is a hollow structure and consists of a rod part and a handle, and a second hollow cross structure 14 arranged at the tail end of the rod part is matched with a secondhollow cross structure 13 of the component B to realize the operation of the screwdriver F on the component B;

fig. 11 is a structural schematic diagram of the combination of the driver E and the driver F, the driver E passes through the internal hollow structure of the driver F, and the combination of the driver E and the driver F is realized; thefirst locking structure 17 of the driver E and the second locking structure 18 of the driver F interact to realize the locking and unlocking of the driver E and the driver F.

Fig. 12 is a schematic view of the structure of the matching of the drivers E and F with the components a and B; after the screwdriver E and the screwdriver F are combined, the second hollow cross structure 14 of the screwdriver F is matched with the second hollow cross structure 13 of the component B to realize the operation of the screwdriver F on the component B, the rod part of the screwdriver E penetrates through the hollow structure in the component B, and the prismatic structure 12 at the tail end of the rod part is matched with the prismatic structure in the component A to realize the operation of the screwdriver E on the component A; when the screwdriver E and the screwdriver F are in a locked state, the component A and the component B do not move relatively, the screwdriver E and the screwdriver F synchronously implant the component A and the component B into bones, the operation habit of a doctor is not changed, and the learning curve is smooth; when bottle opener E and bottle opener F are in non-locking state, bottle opener E control assembly A does not rotate, and bottle opener F control assembly B makes subassembly B rotate around assembly A, shortens screw length, and the first screw thread 1 of pulling subassembly A is carried, compresses cancellous bone, produces and adds pressure, and this technique makes the doctor can well judge the change of adding pressure, is favorable to reducing the smooth silk incidence of screw, improves the fixed effect of screw.

Fig. 13 is a structural schematic diagram of a screwdriver G, the screwdriver F is composed of a rod part and a handle, a fortieth-shaped structure arranged at the tail end of the rod part is used for operating 16 to be matched with a thirty-shapedstructure 13 of a component C, and the component C is operated by the screwdriver G; the handle of the screwdriver G is provided with a rough surface, which is beneficial to the operation and use of the screwdriver G.

Fig. 14 is a schematic structural view of the driver G passing through the interior of the driver F.

Fig. 15 is a schematic view of the structure of the driver G passing through the hollow structure inside the driver F to match the component C with the components a and B. The component C is inserted into the hollow structure in the component B by the screwdriver G, and at the moment, one end of the thirdexternal thread 6 of the component C is inserted into the hollow structure in the component A; next, the component B is controlled not to rotate by the driver F, and the component C is rotated by the driver G so that the thirdexternal thread 6 of the component C matches the first internal thread 3 of the component a, and the fourthexternal thread 6 of the component C matches the thirdinternal thread 5 of the component B, and at this time, the component a and the component B are in a locked state.

FIG. 16 is a schematic view of a locking combination compression screw according to the present invention implanted into a bone, wherein component A and component B interact to generate a compressive force for compression fixation of a fracture; the component C is matched and locked with the component A and the component B to realize the locking of the component A and the component B; when external force acts on one of the fracture blocks to enable the fracture block to rotate relative to the other fracture block, the component A and the component B in the locking state cannot rotate mutually, and the occurrence rate of delayed healing of fracture deformity and bone nonunion caused by internal fixation failure due to the fact that the component A and the component B rotate mutually and the length of a screw is lengthened is avoided.

The ipsilateral intra-articular fracture referred to in the present patent refers to the side that comes into contact with the compression structure of the component B, and the contralateral intra-articular fracture refers to a fracture that corresponds to the ipsilateral intra-articular fracture.

The technical scheme of the invention is suitable for treating various fractures, in particular to intra-articular fracture, femoral neck fracture, dentate process fracture and the like. The following is a detailed description of the use of the device according to the invention in connection with a tibial plateau fracture surgery:

the first step is as follows: according to the standard operation flow, disinfecting and laying a sheet, exposing the fracture according to the standard operation approach, resetting, temporarily fixing the fracture by using a Kirschner wire or a resetting clamp, and confirming good resetting through fluoroscopy; and (3) punching a proper part of the fracture block in the ipsilateral joint to the fracture block in the contralateral joint by using the special rotating head for operation, and measuring the depth of the nail hole.

The second step is that: based on the depth of the nail hole being measured, the appropriate length of assembly a and assembly B is selected and assembled so that the end of assembly B is flush with the first graduation marks 9 on assembly a. According to the requirement, the groove structures on the surfaces of the component A and the component B are filled with substances for promoting bone healing, such as bone morphogenetic proteins and the like.

The third step: screw implantation, reduction and compression fixation of fracture: combining the driver E and the driver F, so that the prism-shaped structure 12 at the tail end of the driver E is embedded with the hollow prism-shaped structure 11 at the tail part of the component A, the second hollow cross-shaped structure 14 at the tail end of the driver F is embedded with the first hollow cross-shaped structure 13 of the component B, and then pushing the second locking structure 18 on the external driver F to act on the first locking structure 17 on the internal driver E to complete the locking between the driver E and the driver F, wherein the component A, the component B, the driver E and the driver F are integrated as a whole as shown in FIG. 12; next, the assembled component A and component B are implanted into the bone through the locked screwdriver E and screwdriver F until the second scale mark 10 on the component B is flush with the bone surface; then, a second locking structure 20 on the external screw driver F is pushed reversely, so that the screw driver F and the screw driver F are unlocked, the screw driver E is used for controlling the component A not to rotate, the screw driver F is rotated clockwise, the component B is rotated clockwise by taking the component A as an axis, the integral length after the component A and the component B are combined is shortened, the fracture is reduced, the first thread 1 of the component A is pulled, cancellous bone around the first thread 1 is compressed, pressure is generated, and the fracture stability is reconstructed; in the process, doctors can carefully experience the change of the pressurizing force to accumulate clinical experience for the next operation;

the fourth step: the screw locking steps are as follows: firstly, the screw driver E is drawn out of the screw driver F; then, selecting a component C with a proper length, matching thesecond cross structure 15 of the component C with thesecond cross structure 16 of the driver G, and then operating the component C by the driver G to insert into the component B through the hollow structure of the driver F, wherein one end of the thirdexternal thread 6 of the component C is inserted into the hollow structure of the component A, and the state is shown in FIG. 12; next, the component B is controlled not to rotate by the screwdriver F, and the component C is rotated by the screwdriver G, so that the thirdexternal thread 6 of the component C is matched with the first internal thread 3 of the component A, and the fourthexternal thread 6 of the component C is matched with the thirdinternal thread 5 of the component B; so that the components a and B are in a locked state as shown in fig. 16; finally, the component C is screwed, so that the component C and the component A are locked with the component B, and the possibility of loosening of the component C is reduced.

The fifth step: implanting a plurality of locking combined compression screws according to the same flow according to the requirement, performing fluoroscopy again to confirm that the fracture reduction and the internal fixation position are good, flushing the wound surface, stopping bleeding exactly, and then suturing to the skin in sequence;

and a sixth step: the relevant size in the operation can be continuously adjusted according to different disease conditions;

the above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims (9)

1. A locking combination compression screw characterized by: comprises a component A, a component B and a component C,

a first external thread 1 and a second external thread 2 are arranged on the surface of the component A, one end of the component A close to the second external thread 2 is of a hollow structure, and a first internal thread 3 is arranged in the hollow structure;

the component B is of a hollow structure, a second internal thread 4 and a third internal thread 5 are arranged in the hollow structure, and the second internal thread 4 is matched with the second external thread 2 of the component A so as to realize the connection of the component A and the component B; the end part of the component B close to the third internal thread 5 is provided with a pressurizing structure;

the subassembly C surface is provided with third external screw thread 6 and fourth external screw thread 7, third external screw thread 6 with the first internal thread 3 phase-match of subassembly A to realize being connected of subassembly C and subassembly A, fourth external screw thread 7 with the third internal thread 5 phase-match of subassembly B, in order to realize being connected of subassembly C and subassembly A.

2. The locking combination compression screw of claim 1, wherein:

the second external thread 2 of the component A and the second internal thread 4 of the component B are a first pair of threads, the third external thread 6 of the component C and the first internal thread 3 of the component A are a second pair of threads, and the fourth external thread 7 of the component C and the third internal thread 5 of the component B are a third pair of threads; the thread pitch and the thread rotation direction of the second pair of threads and the third pair of threads are the same, and the thread pitch and/or the thread rotation direction of the first pair of threads are different from those of the second pair of threads and the third pair of threads.

3. The locking combination compression screw of claim 1, wherein:

the pressurizing structure of the component B is an expanded hemispherical structure arranged at one end, close to the third internal thread 5, of the component B, a fifth external thread 8 is arranged on the surface of the pressurizing structure of the component B, and the fifth external thread 8 can be screwed into a bone fracture plate or a bone.

4. The locking combination compression screw of claim 1, wherein:

be provided with first scale mark 9 between subassembly A's first external screw thread 1 and the second external screw thread 2, first scale mark 9 is the scale mark of instructing subassembly B assembly degree of depth on subassembly A, and when subassembly B second internal thread 4 rotated on subassembly A second external screw thread 2 promptly, subassembly B is terminal to flush with first scale mark 9.

5. The locking combination compression screw of claim 1, wherein: the surface of the component B is provided with a second scale mark 10, the second scale mark 10 is a scale mark for indicating the depth of the component B implanted into the bone, namely when the assembled component A and the assembled component B are implanted into the bone, the second scale mark 10 on the component B is flush with the surface of the bone.

6. The locking combination compression screw of claim 1, wherein: the surface of the component A and/or the component B is formed with an uneven structure which can be filled with a medicament beneficial to bone healing.

7. The locking combination compression screw of claim 1, wherein: the surface of the component A and/or the component B is subjected to sand blasting or porous and hydroxyapatite protruding treatment to form micropores.

8. A driver for use with the locking combination compression screw of any one of claims 1 to 7, wherein: comprises a screwdriver E, a screwdriver F and a screwdriver G,

the screwdriver E is provided with a prismatic structure 12 at one end, and the prismatic structure 12 is matched with the hollow prismatic structure 11 of the component A, so that the screwdriver E can operate the component A;

the end of the screw driver F is provided with a second hollow cross structure 14, and the second hollow cross structure 14 is matched with a first hollow cross structure 13 arranged in the pressurizing structure of the component B, so that the screw driver F can operate the component B;

the end of the screwdriver G is provided with a second cross-shaped structure 16, and the second cross-shaped structure 16 is matched with the first cross-shaped structure 15 arranged at the tail end of the fourth external thread 7 of the component C, so that the screwdriver G can operate the component C;

the screwdriver F is a hollow structure, and after the screwdriver F is connected with the component B through the second hollow cross structure 14 and the first hollow cross structure 13, the screwdriver E and the screwdriver G can respectively penetrate through the screwdriver F to realize the operation and control of the component A and the component C.

9. The driver of claim 8 wherein: the screwdriver E and the screwdriver F are respectively provided with a first locking structure 17 and a second locking structure 18 which are matched with each other, the second locking structure 18 on the screwdriver F is pushed, and the locking between the screwdriver E and the screwdriver F is completed; the second locking structure 18 on the driver F is pushed in reverse to release the locking between the driver E and the driver F.

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