CN111692187B

CN111692187B - Anti-corrosion anti-loose combined fastener

Info

Publication number: CN111692187B
Application number: CN202010608579.5A
Authority: CN
Inventors: 管佳夫
Original assignee: Yuhuan Xingqi Power Co ltd
Current assignee: Yuhuan Xingqi Power Co.,Ltd.
Priority date: 2020-06-30
Filing date: 2020-06-30
Publication date: 2021-09-14
Anticipated expiration: 2040-06-30
Also published as: CN111692187A

Abstract

The invention belongs to the field of fasteners, and particularly relates to a corrosion-resistant anti-loosening combined fastener which comprises a nut, an internal thread, a bolt, an external thread A, a limiting rod, a return spring, a ring sleeve A, an external thread B, a spiral surface, a clamping block, a linkage rod and a volute spring, wherein three annular grooves A which are uniformly distributed in the axial direction are formed in a cylindrical surface where the external thread A of the bolt is located, and one annular groove A is communicated with the tail end of the cylindrical surface where the external thread A is located; according to the invention, through the special structure of the internal thread on the nut, the special structure of the external thread A on the bolt and the special structure of the external thread B on the ring sleeve A, the nut can be quickly installed and screwed into the bolt, meanwhile, the effective pre-tightening between the parts made of softer materials is realized, and the practical effect of the quick-assembling bolt in fastening the parts made of soft materials is avoided.

Description

Anti-corrosion anti-loose combined fastener

Technical Field

The invention belongs to the field of fasteners, and particularly relates to a corrosion-resistant anti-loose combined fastener.

Background

The maximum fastening angle of the traditional quick-mounting bolt is 90 degrees, so that the quick-mounting bolt is suitable for fastening connection between harder equipment and not suitable for fastening connection between softer equipment.

The quick mounting bolt in the prior art effectively improves the fastening efficiency of the quick mounting bolt to equipment in the process of fastening the equipment, thereby improving the working efficiency and accelerating the speed of bolt mounting.

When the traditional fast-assembling bolt is used for fastening equipment made of softer materials, if the threaded matching part of the nut and the bolt still does not finish effective pre-tightening on the equipment after the nut and the bolt are rotated for 90 degrees, when the nut is continuously rotated on the basis, the internal thread on the nut and the external thread of the bolt can be separated under the condition of continuously rotating the nut, and then the bolt and the nut which are originally in a fastening state are axially separated, so that the bolt and the nut completely lose efficacy in fastening the equipment.

After the conventional common bolt is used for effectively fastening equipment, the fastening state of the bolt needs to be locked by auxiliary components such as double nuts or elastic washers, so that the bolt in the effective fastening state of the equipment cannot be loosened after the equipment is frequently vibrated, and the bolt is ensured to continuously fasten the equipment.

Therefore, it is necessary to design a quick-assembly fastener which is suitable for equipment made of different hardness materials and can be locked and released by self.

The invention designs a corrosion-resistant anti-loose combined fastener to solve the problems.

Disclosure of Invention

In order to solve the defects in the prior art, the invention discloses a corrosion-resistant anti-loose combined fastener which is realized by adopting the following technical scheme.

In the description of the present invention, it should be noted that the terms "inside", "outside", "upper", "lower", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or orientations or positional relationships that the products of the present invention conventionally use, which are merely for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, or be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.

A corrosion-resistant anti-loose combined fastener comprises a nut, an internal thread, a bolt, an external thread A, a limiting rod, a return spring, a ring sleeve A, an external thread B, a spiral surface, a clamping block, a linkage rod and a volute spring, wherein three annular grooves A which are uniformly distributed in the axial direction are formed in a cylindrical surface where the external thread A of the bolt is located, and one annular groove A is communicated with the tail end of the cylindrical surface where the external thread A is located; a ring sleeve A is rotatably matched in each ring groove A; the outer side of each ring sleeve A is provided with an external thread B which has the same rotating direction and the same thread pitch as the external thread A; a volute spiral spring for rotationally resetting the ring sleeve A is arranged between the ring sleeve A and the bolt; the clamping block arranged on the inner wall of the ring sleeve A moves in the arc-shaped swing groove A on the inner wall of the corresponding ring groove A; the inner wall of each ring sleeve A is provided with a linkage rod, and the three linkage rods are sequentially matched; the tail end ring sleeve A rotating in the same direction with the rotation direction of the external thread A drives the other two ring sleeves A to synchronously rotate through the matching of the three linkage rods, and the innermost ring sleeve A rotating in the opposite direction to the rotation direction of the external thread A drives the other two ring sleeves A to synchronously and reversely rotate through the sequential matching of the three linkage rods.

Two chutes A with 90-degree radian symmetrically arranged on the cylindrical surface of the internal thread of the nut are axially and slidably matched with the external thread A and the external thread B, and two chutes B with 90-degree radian symmetrically arranged on the cylindrical surface of the internal thread and the external thread A are axially and slidably matched with the chutes D with 90-degree radian symmetrically arranged on the cylindrical surface of the external thread B; the internal thread is matched with the external thread A and the external thread B; two helicoids which have the same rotating direction with the external thread B and are matched with the internal thread are symmetrically arranged on the external thread B.

A sliding chute C communicated with the three swinging grooves A is formed in the end face of the bolt, and a limiting rod matched with the three clamping blocks axially slides in the sliding chute C; three limit-releasing grooves matched with the clamping blocks are formed in the limiting rod, and a reset spring for resetting the limiting rod is installed in the sliding groove C.

As the further improvement of this technique, above-mentioned internal thread one corner have with corresponding helicoid complex effect inclined plane, guarantee that the helicoid on internal thread and the corresponding external screw thread B cooperates well, prevent that the internal thread on the nut from offseting with the helicoid top on the external screw thread B in the spout B on the external screw thread A and the spout D axial slip in-process on the external screw thread B along, guarantee that the nut is installed to the bolt smoothly.

As a further improvement of the technology, the three linkage rods are movably arranged in a swing groove B which is communicated with the inner cylindrical surfaces of the three ring grooves A in the bolt; and a guide block is arranged on the limiting rod and axially slides in a guide groove on the inner wall of the chute C. The swing groove B provides a movable space for three linkage rods arranged on the inner walls of the three ring sleeves A.

As a further improvement of the technology, the nut and the bolt are both made of 45 steel or 40 boron steel or 20 manganese titanium boron steel or 35CrMoA, so as to enhance the strength of the bolt and the nut.

As a further improvement of the technology, the bolt and the nut adopt an electroplating chromium process to enhance the corrosion resistance of the bolt and the nut.

As a further improvement of the technology, the volute spiral spring is nested in the annular groove A and is positioned in an annular groove B on the inner wall of the corresponding annular sleeve A; one end of the volute spiral spring is connected with the inner wall of the corresponding annular groove A, and the other end of the volute spiral spring is connected with the inner wall of the corresponding annular groove B. The annular groove A provides accommodating space for the spiral spring, and reduces the space occupied by the spiral spring on the bolt.

As a further improvement of the technology, an outer hexagonal ring sleeve B with the same central axis is arranged on the end surface of the tail end ring sleeve A, and the ring sleeve B is matched with a wrench; the tail end of the bolt is provided with a fixed column which is the same as the central axis, and the tail end of the fixed column is provided with a hexagonal boss matched with the wrench; one end of the reset spring is connected with the inner wall of the chute C, and the other end of the reset spring is connected with the end face of the limiting rod.

Compared with the traditional fast-assembling fastening bolt, the fast-assembling fastening bolt has the advantages that the fast installation and screwing of the nut to the bolt can be realized through the special structure of the internal thread on the nut, the special structure of the external thread A on the bolt and the special structure of the external thread B on the ring sleeve A, meanwhile, the effective pre-tightening of the soft material parts is realized, and the practical effect of the fast-assembling bolt in fastening the soft material parts is avoided. The bolt and the nut which are already in a fastening state can be locked by rotating the ring sleeve A in the same direction as the rotating direction of the external thread B, so that the bolt has the function of loosening and releasing the traditional bolt only through auxiliary components such as an elastic washer and the like, and the continuity of effective fastening of the bolt to the components is improved. In addition, the nut and the bolt in the invention are made of 45 steel or 40 boron steel or 20 manganese titanium boron steel or 35CrMoA, so the strength is high. Meanwhile, the bolt and the nut both adopt a chromium electroplating process, so the invention has stronger corrosion resistance. The invention has simple structure and better use effect.

Drawings

Fig. 1 is an overall schematic view of the present invention.

FIG. 2 is a cross-sectional view of the bolt, spiral spring and collar A.

FIG. 3 is a cross-sectional view of the bolt and the stop lever.

FIG. 4 is a cross-sectional view of the bolt, the linkage rod, the spiral spring and the ring cover A.

Fig. 5 is a schematic cross-sectional view of the ring sheath a, the locking block, the limiting rod, the bolt and the linkage rod.

Fig. 6 is a schematic view of a nut.

Fig. 7 is a schematic cross-sectional view of a bolt and its bolt.

Fig. 8 is a schematic cross-sectional view of the arrangement of the swing groove B and the sliding groove C on the bolt.

Fig. 9 is a schematic view of a stop lever.

Fig. 10 is a schematic cross-sectional view of the cuff B.

Number designation in the figures: 1. a nut; 2. an internal thread; 3. a chute A; 4. an acting bevel; 5. a bolt; 6. an external thread A; 7. a chute B; 8. a ring groove A; 9. a swinging groove A; 10. a chute C; 11. a swing groove B; 12. a limiting rod; 13. a limit relief groove; 14. a guide block; 15. a return spring; 16. a ring sleeve A; 17. an external thread B; 18. a chute D; 19. a helicoid; 20. a ring groove B; 21. a clamping block; 22. a linkage rod; 23. a volute spiral spring; 24. a guide groove; 25. a ring sleeve B; 27. fixing a column; 28. hexagonal boss.

Detailed Description

The drawings are schematic illustrations of the implementation of the present invention to facilitate understanding of the principles of structural operation. The specific product structure and the proportional size are determined according to the use environment and the conventional technology.

As shown in fig. 1, 2 and 3, the device comprises a nut 1, an internal thread 2, a bolt 5, an external thread a6, a limiting rod 12, a return spring 15, a ring sleeve a16, an external thread B17, a spiral surface 19, a clamping block 21, a linkage rod 22 and a spiral spring 23, wherein as shown in fig. 7, three annular grooves A8 which are uniformly distributed in the axial direction are formed on a cylindrical surface where the external thread a6 of the bolt 5 is located, and one annular groove A8 is communicated with the tail end of the cylindrical surface where the external thread a6 is located; as shown in fig. 1, 2 and 3, a ring sleeve a16 is rotatably matched in each ring groove A8; as shown in fig. 1 and 10, the outer side of each ring sleeve a16 is provided with an external thread B17 which is the same as the thread a6 in the same direction and pitch; as shown in fig. 3 and 4, a spiral spring 23 for rotationally restoring the ring sleeve a16 is arranged between the ring sleeve a16 and the bolt 5; as shown in fig. 5, 7 and 10, the latch 21 mounted on the inner wall of the ring sheath a16 moves in the arc-shaped swing groove a9 on the inner wall of the corresponding ring groove A8; as shown in fig. 3, 5 and 10, the inner wall of each ring sleeve a16 is provided with a linkage rod 22, and the three linkage rods 22 are sequentially matched; as shown in fig. 1, 3 and 5, the terminal ring sleeve a16 rotating in the same direction as the rotation direction of the external thread a6 drives the other two ring sleeves a16 to rotate synchronously through the cooperation of the three linking rods 22, and the innermost ring sleeve a16 rotating in the opposite direction to the rotation direction of the external thread a6 drives the other two ring sleeves a16 to rotate synchronously and reversely through the sequential cooperation of the three linking rods 22.

As shown in fig. 1 and 6, two sliding grooves A3 with 90-degree radian symmetrically formed on the cylindrical surface where the internal thread 2 of the nut 1 is located are axially and slidably matched with the external thread a6 and the external thread B17; as shown in fig. 6, 7 and 10, the internal thread 2 is axially in sliding fit with two 90-degree-radian sliding grooves B7 symmetrically formed on the cylindrical surface on which the external thread a6 is located and two 90-degree-radian sliding grooves D18 symmetrically formed on the cylindrical surface on which the external thread B17 is located; the internal thread 2 is matched with the external thread A6 and the external thread B17; the external thread B17 is symmetrically provided with two helicoids 19 which have the same rotating direction as the external thread B17 and are matched with the internal thread 2.

As shown in fig. 7 and 8, a chute C10 communicated with the three swinging grooves a9 is arranged on the end surface of the bolt 5. As shown in fig. 4, 5 and 7, a limiting rod 12 matched with the three clamping blocks 21 is axially slid in the sliding groove C10; as shown in fig. 3, 5 and 9, the limiting rod 12 is provided with three limiting-releasing grooves 13 engaged with the latch 21, and the sliding groove C10 is provided with a return spring 15 for returning the limiting rod 12.

As shown in fig. 6, one corner of the internal thread 2 has an acting inclined surface 4 which is matched with the corresponding spiral surface 19, so that the internal thread 2 is ensured to be well matched with the spiral surface 19 on the corresponding external thread B17, the internal thread 2 on the nut 1 is prevented from abutting against the top end of the spiral surface 19 on the external thread B17 in the process of axially sliding along the sliding groove B7 on the external thread a6 and the sliding groove D18 on the external thread B17, and the nut 1 is ensured to be smoothly mounted on the bolt 5.

As shown in fig. 3, 5 and 7, the three linking rods 22 are movably arranged in a swing groove B11 in the bolt 5, which is communicated with the inner cylindrical surfaces of the three ring grooves A8; the limiting rod 12 is provided with a guide block 14, and the guide block 14 axially slides in a guide groove 24 on the inner wall of the slide groove C10. The swing groove B11 provides a moving space for the three linking rods 22 arranged on the inner walls of the three ring sleeves A16.

As shown in fig. 1, the nut 1 and the bolt 5 are made of 45 steel or 40 boron steel or 20 manganese titanium boron steel or 35CrMoA to enhance the strength of the nut 1 of the bolt 5.

As shown in fig. 1, the bolt 5 and the nut 1 are processed by chrome plating to enhance corrosion resistance of the bolt 5 and the nut 1.

As shown in fig. 2, 4 and 10, wrap spring 23 is nested in groove A8 and is seated in groove B20 on the inner wall of the corresponding ring housing a 16; one end of scroll spring 23 is connected to the inner wall of the corresponding groove A8, and the other end is connected to the inner wall of the corresponding groove B20. Groove A8 provides a space for spiral spring 23 to accommodate, and reduces the space occupied by spiral spring 23 on bolt 5.

As shown in fig. 1 and 2, an outer hexagonal ring B25 with the same central axis is arranged on the end surface of the end ring sleeve a16, and the ring sleeve B25 is matched with a wrench; a fixing column 27 which is the same as the central axis is arranged at the tail end of the bolt 5, and a hexagonal boss 28 matched with a wrench is arranged at the tail end of the fixing column 27; one end of the return spring 15 is connected with the inner wall of the chute C10, and the other end is connected with the end face of the limiting rod 12.

According to the invention, the height of the nut 1 is greater than that of the ring sleeve A16, the height of the ring sleeve A16 is equal to that of the adjacent external thread A6, the nut 1 is ensured to be screwed with the external thread A6 and simultaneously interact with the ring sleeve A16, and further, after the nut 1 rotates for 90 degrees relative to the bolt 5, the nut 1 drives the ring sleeve A16 to synchronously rotate for 90 degrees and is continuously meshed with the external thread B17 on the ring sleeve A16 when the nut 1 is gradually separated from the external thread A6 on the bolt 5, so that the external thread A6 and the external thread B17 form a complete thread, and the internal thread 2 of the nut 1 is ensured to be screwed with the external thread B17 on the corresponding ring sleeve A16 when the external thread A6 on the bolt 5 is completely separated, and the equipment is continuously fastened.

The working process of the invention is as follows: in the initial state, the latch 21 contacts the limiting rod 12, the limit-releasing groove 13 on the limiting rod 12 is staggered with the latch 21, and the spiral spring 23 is in the pre-compression energy-storage state. The ring groove D on the ring sleeve A16 is opposite to the external thread A6 on the bolt 5, and the external thread B17 on the ring sleeve A16 is opposite to the sliding groove B7 on the bolt 5. The external thread B17 on the collar a16 forms a complete thread with the external thread a6 on the bolt 5. Three traces 22 are in contact in sequence.

When the device needs to be fastened by using the invention, the bolt 5 is firstly inserted into a round hole at the fastening position of the device, and then the two parts of the internal thread 2 with the radian of ninety degrees on the inner wall of the nut 1 are opposite to the sliding groove B7 on the bolt 5 and the screw surface 19 of the external thread B17 on the ring sleeve A16.

The nut 1 is slid fast axially onto the bolt 5, the internal thread 2 on the nut 1 first interacting with the helical surface 19 of the external thread B17 on the end collar a 16. The internal thread 2 on the nut 1 drives the tail end ring sleeve A16 to rotate along the direction opposite to the rotating direction of the external thread A6 relative to the bolt 5 through the spiral surface 19 of the external thread B17 on the ring sleeve A16, the spiral spring 23 of the ring sleeve A16 which generates rotation is further compressed to store energy, the fixture block 21 is separated from the limiting rod 12 along with the rotation of the ring sleeve A16, and the rotating ring sleeve A16 drives the linkage rod 22 arranged on the inner wall of the rotating ring sleeve A16 to be separated from the linkage rod 22 arranged on the inner wall of the adjacent ring sleeve A16. Since the screw surface 19 on the external thread B17 of the ring a16 has the same screw direction as the screw direction of the external thread B17, during the relative axial movement of the internal thread 2 of the nut 1 with respect to the external thread B17 on the ring a16, the external thread B17 on the ring a16 does not engage in the internal thread 2 on the nut 1 in the opposite direction under the restoring action of the corresponding spiral spring 23, so that the axial sliding of the nut 1 with respect to the bolt 5 is prevented. The two-part external thread B17 on the ring a16 and the two-part external thread a6 on the bolt 5 slide axially in two slide grooves A3 on the inner wall of the nut 1.

If a certain ring A16 on the bolt 5 is partially located in the bolt 5 hole on the device and partially exposed out of the bolt 5 hole on the device. The axial movement of the nut 1 relative to the bolt 5 is stopped when the nut 1 is about to pass the external thread a6 closest to the side wall of the device. The nut 1 is slightly adjusted in the axial direction with respect to the bolt 5 so that the internal thread 2 on the nut 1 and the external thread a6 on the bolt 5 are in a pre-screwing opposed state, and starts to screw the nut 1 onto the external thread a6 on the bolt 5 and brings the nut 1 close to the apparatus side wall.

Simultaneously, the nut 1 starts to be screwed with the external thread B17 on the ring sleeve A16 which is partially exposed out of the hole of the bolt 5 on the equipment. Because the fixture block 21 installed on the inner wall of the ring sleeve A16 partially exposed out of the hole of the bolt 5 on the device is still in contact with the limiting rod 12, the ring sleeve A16 partially exposed out of the hole of the bolt 5 on the device cannot rotate relative to the bolt 5 under the action of the nut 1. When nut 1 is disengaged from previously applied collar a16, collar a16, previously applied to nut 1, is momentarily returned to its original position by the action of the corresponding wrap spring 23.

If a certain external thread A6 on the bolt 5 is partially positioned in the bolt 5 hole on the equipment and partially exposed out of the bolt 5 hole on the equipment. When the nut 1 axially reaches the side wall of the device, the ring A16 in the nut 1 is still not reset by the thread 2 in the nut 1. At this time, the nut 1 is slightly adjusted in the axial direction with respect to the bolt 5 so that the internal thread 2 on the nut 1 and the external thread a6 on the bolt 5 are in a pre-screwing opposing state, and the nut 1 starts to be screwed onto the external thread a6 on the bolt 5 and the nut 1 is fastened to the device.

At the same time, inner ring a16 of nut 1 returns to its original position with the nut 1 being screwed onto bolt 5 by the return action of the corresponding spiral spring 23. When the nut 1 is screwed on the bolt 5 by an angle of 90 degrees, the ring sleeve A16 in the nut 1 is completely reset, and the fixture block 21 is contacted with the limiting rod 12 again. As the nut 1 continues to rotate, the internal threads 2 on the nut 1 begin to thread with the external threads B17 on the collar a16 located therein.

At this time, the fixture block 21 installed on the inner wall of the ring sleeve a16 inside the nut 1 contacts with the limiting rod 12, so that the ring sleeve a16 is prevented from rotating under the driving of the nut 1, thereby ensuring that the nut 1 cannot rotate relative to the bolt 5 under the driving of the nut 1 in the screwing process of the nut 1 and the external thread B17 on the ring sleeve a16, ensuring that the external thread B17 on the ring sleeve a16 is well screwed with the nut 1, increasing the screwing axial stroke of the nut 1 relative to the bolt 5, further fastening the equipment by the nut 1, and being applicable to fastening equipment made of softer materials.

When the nut 1 is screwed with the external thread B17 on the ring sleeve A16 or the external thread A6 on the bolt 5 to effectively fasten the equipment, the limiting rod 12 is pulled outwards, the return spring 15 is further stretched to store energy, and the limit releasing grooves 13 on the limiting rod 12 are respectively opposite to the corresponding clamping blocks 21. Then, through the matching of two wrenches with the hexagonal boss 28 and the outer hexagonal ring sleeve B25 on the fixed column 27, the ring sleeve B25 is rotated along the same direction as the rotation direction of the external thread a6 relative to the bolt 5, the ring sleeve B25 drives the ring sleeve a16 at the tail end to rotate synchronously, the ring sleeve a16 at the tail end drives the other two ring sleeves a16 to rotate synchronously by a slight angle through the linkage rod 22, the spiral spring 23 corresponding to the ring sleeve a16 releases a little energy and is still in a compression energy storage state, and the fixture block 21 enters the corresponding limit-releasing groove 13 on the limiting rod 12 by a slight distance. The ring sleeve A16 directly acting on the nut 1 rotates in the same direction relative to the nut 1 in a fastening state, the external thread B17 on the ring sleeve A16 and the internal thread 2 of the nut 1 generate relative movement along the axial direction, the external thread B17 on the ring sleeve A16 drives the nut 1 to have an axial inward movement trend through the internal thread 2 on the nut 1, so that the internal thread 2 on the nut 1 and the external thread A6 on the bolt 5 are axially extruded, the state between the nut 1 and the bolt 5 is locked, and looseness is prevented between the nut 1 and the bolt 5 in an effective fastening state when frequent vibration occurs to equipment.

When it is necessary to disassemble the nut 1 and the bolt 5 in the fastening state, the nut 1 is rotated reversely, the nut 1 drives the ring sleeve a16 engaged therewith to rotate reversely relative to the bolt 5, and the corresponding spiral spring 23 is further compressed. The ring sleeve A16 matched with the nut 1 drives the corresponding block 21 to be separated from the corresponding limit releasing groove 13 on the limit rod 12. Meanwhile, the ring A16 engaged with the nut 1 drives the other two rings A16 to reset relative to the bolt 5 through the corresponding linkage rods 22. When the clamping blocks 21 on the three ring sleeves A16 are simultaneously separated from the corresponding limit-releasing grooves 13, the limit rod 12 is instantaneously reset under the action of the reset spring 15. At this point, reverse rotation of the nut 1 is continued until the nut 1 is completely unscrewed from the bolt 5.

In conclusion, the beneficial effects of the invention are as follows: according to the invention, through the special structure of the internal thread 2 on the nut 1, the special structure of the external thread A6 on the bolt 5 and the special structure of the external thread B17 on the ring sleeve A16, the nut 1 can be quickly installed and screwed into the bolt 5, meanwhile, the effective pre-tightening of the softer material parts is realized, and the practical effect of the quick-assembling bolt 5 in fastening the soft material parts is avoided. The bolt 5 and the nut 1 which are already in a fastened state can be locked by rotating the ring sleeve A16 in the same direction as the rotating direction of the external thread B17, so that the bolt 5 has the function of loosening and releasing the traditional bolt 5 only through auxiliary components such as elastic washers, and the continuity of effective fastening of the bolt 5 to the components is improved. In addition, since the nut 1 and the bolt 5 of the present invention are made of 45 steel or 40 boron steel or 20 manganese titanium boron steel or 35CrMoA, the strength thereof is high. Meanwhile, the bolt 5 and the nut 1 both adopt a chromium electroplating process, so that the invention has stronger corrosion resistance.

Claims

1. A corrosion-resistant anti-loose combined fastener is characterized in that: the spiral spring comprises a nut, an internal thread, a bolt, an external thread A, a limiting rod, a return spring, a ring sleeve A, an external thread B, a spiral surface, a clamping block, a linkage rod and a spiral spring, wherein three annular grooves A which are uniformly distributed in the axial direction are formed in a cylindrical surface where the external thread A of the bolt is located, and one annular groove A is communicated with the tail end of the cylindrical surface where the external thread A is located; a ring sleeve A is rotatably matched in each ring groove A; the outer side of each ring sleeve A is provided with an external thread B which has the same rotating direction and the same thread pitch as the external thread A; a volute spiral spring for rotationally resetting the ring sleeve A is arranged between the ring sleeve A and the bolt; the clamping block arranged on the inner wall of the ring sleeve A moves in the arc-shaped swing groove A on the inner wall of the corresponding ring groove A; the inner wall of each ring sleeve A is provided with a linkage rod, and the three linkage rods are sequentially matched; the tail end ring sleeve A rotating in the same direction with the rotation direction of the external thread A drives the other two ring sleeves A to synchronously rotate through the matching of the three linkage rods, and the innermost ring sleeve A rotating in the opposite direction to the rotation direction of the external thread A drives the other two ring sleeves A to synchronously and reversely rotate through the sequential matching of the three linkage rods;

two chutes A with 90-degree radian symmetrically arranged on the cylindrical surface of the internal thread of the nut are axially and slidably matched with the external thread A and the external thread B, and two chutes B with 90-degree radian symmetrically arranged on the cylindrical surface of the internal thread and the external thread A are axially and slidably matched with the chutes D with 90-degree radian symmetrically arranged on the cylindrical surface of the external thread B; the internal thread is matched with the external thread A and the external thread B; the external thread B is symmetrically provided with two helicoids which have the same rotating direction as the external thread B and are matched with the internal thread;

2. A corrosion resistant loose resistant combination fastener as defined in claim 1, wherein: one corner of the internal thread is provided with an acting inclined plane matched with the corresponding spiral surface.

3. A corrosion resistant loose resistant combination fastener as defined in claim 1, wherein: the three linkage rods are movably arranged in a swing groove B communicated with the inner cylindrical surfaces of the three annular grooves A in the bolt; and a guide block is arranged on the limiting rod and axially slides in a guide groove on the inner wall of the chute C.

4. A corrosion resistant loose resistant combination fastener as defined in claim 1, wherein: the nut and the bolt are made of 45 steel, 40 boron steel, 20 manganese titanium boron steel or 35 CrMoA.

5. A corrosion resistant loose resistant combination fastener as defined in claim 1, wherein: the bolt and the nut both adopt a chromium electroplating process.

6. A corrosion resistant loose resistant combination fastener as defined in claim 1, wherein: the volute spiral spring is nested in the annular groove A and is positioned in an annular groove B on the inner wall of the corresponding ring sleeve A; one end of the volute spiral spring is connected with the inner wall of the corresponding annular groove A, and the other end of the volute spiral spring is connected with the inner wall of the corresponding annular groove B.

7. A corrosion resistant loose resistant combination fastener as defined in claim 1, wherein: the end surface of the tail end ring sleeve A is provided with an outer hexagonal ring sleeve B which is coaxial with the central axis, and the ring sleeve B is matched with a wrench; the tail end of the bolt is provided with a fixed column which is the same as the central axis, and the tail end of the fixed column is provided with a hexagonal boss matched with the wrench; one end of the reset spring is connected with the inner wall of the chute C, and the other end of the reset spring is connected with the end face of the limiting rod.