Internal wedge-shaped piece bolt and prestress adjusting method thereof

Abstract

The invention discloses an internal wedge-shaped piece bolt and a prestress adjusting method thereof, and relates to the technical field of bolt thread pre-tightening force. Comprising a bolt body, external threads are arranged on the outer wall of the bolt body, a nut is connected outside the bolt body, a wedge-shaped hole extending inwards is formed in the end face of the end, provided with the external threads, of the bolt body, and a threaded hole is formed in the bottom end of the wedge-shaped hole; a through hole is formed in the wedge-shaped piece in the axial direction of the wedge-shaped piece; the end, provided with the threads, of the pressure bolt penetrates through the through hole and is in threaded connection with the threaded hole, and along with increase of the thread screwing length of the pressure bolt and the threaded hole, a bolt head of the pressure bolt extrudes the wedge-shaped piece to move into the wedge-shaped hole, so that the position, provided with the external threads, of the bolt body and the nut are tensioned. According to the bolt with the internal wedge-shaped part, the bolt head of the pressure bolt continuously extrudes the wedge-shaped part, so that the wedge-shaped part extrudes the bolt body, the tightness and safety of connection are improved, and dangerous accidents caused by looseness of the bolt are avoided.

Description

Technical Field

[0001] The invention relates to the technical field of bolt thread preload, and more particularly to an internal wedge-shaped bolt and a preload adjustment method thereof. Background Art

[0002] Bolts are commonly used fasteners, usually made of metal materials, with threads to facilitate the combination with nuts or other components. Its main function is to connect and fix different components, and it is widely used in machinery, construction, automobiles, aviation and other fields. The design and selection of bolts are crucial to the safety and stability of the structure. As an important connector, bolts play an important role in traditional manufacturing and construction. In addition, with the continuous evolution of scientific and technological development and the continuous improvement of manufacturing processes, bolts play an increasingly important role in ensuring structural safety and performance.

[0003] At present, the main manufacturing process of bolts includes cutting, upsetting, heat treatment, turning, grinding, thread rolling, finished product processing, inspection and warehousing, etc. Since the thread surface is very sensitive to notches, bolts are prone to cracking during use, which can lead to failure of the overall equipment load-bearing components and even cause structural fractures leading to casualties.

[0004] Therefore, it is necessary to design an internal wedge bolt to solve the above-mentioned technical problems. Summary of the invention

[0005] In view of this, the present invention provides an internal wedge bolt to strengthen the tension between the bolt body and the nut, enhance the safety and reliability of the bolt connection, and avoid dangerous accidents caused by loosening of the bolt. In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0006] In one aspect, the present invention provides an internal wedge bolt, comprising:

[0007] A bolt body, wherein the outer wall of the bolt body is provided with an external thread, a nut is connected to the outside of the bolt body, a wedge-shaped hole is provided on the end surface of one end of the bolt body provided with the external thread and extends inwardly therefrom, and a threaded hole is provided at the bottom end of the wedge-shaped hole;

[0008] A wedge-shaped member, wherein the wedge-shaped member is provided with a through hole along its axial direction;

[0009] A pressure bolt, wherein one end of the pressure bolt is provided with a thread and passes through the through hole and is threadedly connected to the threaded hole. As the threaded engagement length of the pressure bolt and the threaded hole increases, the bolt head of the pressure bolt squeezes the wedge-shaped piece and moves into the wedge-shaped hole, so that the bolt body is provided with an external thread position and is tightened with the nut.

[0010] Furthermore, a wedge-shaped nut is provided at the bottom end of the wedge-shaped hole, the threaded hole is provided on the wedge-shaped nut, and the wedge-shaped nut is fixedly connected to the wedge-shaped hole.

[0011] Furthermore, a magnet is provided at one end of the wedge-shaped nut away from the wedge-shaped piece, and the wedge-shaped nut is connected to the upper and lower ends of the wedge-shaped hole through the magnet.

[0012] Furthermore, a pair of strain gauges is provided at the connection between the bolt body and the nut.

[0013] On the other hand, the present invention provides a method for adjusting the preload force of an internal wedge bolt, the method using the internal wedge bolt comprising the following steps:

[0014] S10: Connect the nut to the bolt body;

[0015] S20: placing the wedge into the wedge hole;

[0016] S30: Put the threaded end of the pressure bolt through the wedge-shaped piece and into the wedge-shaped hole, rotate the pressure bolt so that the pressure bolt and the threaded hole are threadedly matched, and the pressure bolt pushes the wedge-shaped piece to slide to adjust the preload force of the bolt body.

[0017] It can be seen from the above technical solution that compared with the prior art, the present invention discloses an internal wedge bolt, in which one end of the pressure bolt with a thread is continuously screwed into the threaded hole, and the bolt head of the pressure bolt continuously squeezes the wedge, so that the wedge moves toward the direction close to the threaded hole, and the wedge squeezes the bolt body, thereby increasing the contact area between the bolt body and the nut, increasing the preload force between the threaded body and the nut, improving the tightness and safety of the connection, and avoiding dangerous accidents caused by loosening of the bolt. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0019] Figure 1 A schematic diagram of the structure of the internal wedge bolt provided by the present invention;

[0020] Figure 2 A cross-sectional view of an internal wedge bolt provided by the present invention;

[0021] Figure 3 A schematic diagram of the internal structure of the internal wedge-shaped bolt provided by the present invention;

[0022] Figure 4 A schematic diagram of the internal structure of the wedge nut provided by the present invention.

[0023] In the figure: 1. pressure bolt; 2. nut; 3. wedge-shaped piece; 4. bolt body; 5. wedge-shaped nut. DETAILED DESCRIPTION

[0024] 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.

[0025] See also Figure 1-4 In one aspect, an embodiment of the present invention discloses an internal wedge bolt, comprising:

[0026] The bolt body 4 has an external thread on its outer wall, the bolt body 4 is externally connected to the nut 2, a wedge-shaped hole is provided on the end surface of one end of the bolt body 4 with the external thread, and a threaded hole is provided at the bottom end of the wedge-shaped hole;

[0027] A wedge-shaped member 3, wherein the wedge-shaped member 3 is provided with a through hole along its axial direction;

[0028] A pressure bolt 1, one end of the pressure bolt 1 having a thread passes through a through hole and is threadedly connected to the threaded hole. As the threaded engagement length of the pressure bolt 1 and the threaded hole increases, the bolt head of the pressure bolt 1 squeezes the wedge 3 and moves into the wedge hole, so that the bolt body 4 having an external thread position is tightened with the nut 2.

[0029] After the nut 2 is connected to the bolt body 4, the wedge piece 3 is placed in the wedge-shaped hole, and the end of the pressure bolt 1 with a thread passes through the through hole of the wedge piece 3 and is threadedly connected to the threaded hole. The pressure bolt 1 is rotated to increase the length of the pressure bolt 1 and the threaded hole. During this process, the bolt head of the pressure bolt 1 squeezes the wedge piece 3 to move the wedge piece 3 toward the threaded hole, so that the wedge piece 3 pressurizes the bolt body 4, thereby increasing the contact area between the bolt body 4 and the nut 2, thereby increasing the tightness of the connection between the bolt body 4 and the nut 2.

[0030] In some embodiments, the wedge-shaped member 3 and the wedge-shaped hole are both truncated cone structures, and the diameter of the wedge-shaped hole gradually decreases as the wedge-shaped hole extends from one end of the bolt body 4 provided with an external thread toward the inside of the bolt body 4 .

[0031] The upper bottom end of the wedge 3 is placed into the wedge hole, and the end of the pressure bolt 1 provided with threads extends from the lower bottom end of the wedge 3 into the wedge and penetrates the wedge. In the process of increasing the length of the pressure bolt 1 and the threaded hole, the bolt head of the pressure bolt 1 squeezes the lower bottom end of the wedge to move the wedge into the wedge hole, thereby strengthening the connection between the nut 2 and the bolt body 4. The ability of the connection between the body bolt 4 and the nut 2 to resist cyclic external loads is strengthened, and fatigue failure of the connection between the bolt body 1 and the nut 2 under the action of cyclic external loads is avoided. At the same time, the loosening and wear of the connection of the bolt body 4 can be reduced, thereby extending the service life of the bolt body 4.

[0032] In some embodiments, a wedge-shaped nut 5 is disposed at the bottom end of the wedge-shaped hole, a threaded hole is disposed on the wedge-shaped nut 5, and the wedge-shaped nut 5 is fixedly connected to the wedge-shaped hole.

[0033] The wedge nut 2 is fixed in the wedge hole, and the pressure bolt 1 passes through the wedge piece 3 and is connected to the wedge nut 5. By increasing the length of the threaded connection between the pressure bolt 1 and the wedge nut 5, the bolt head of the pressure bolt 1 pushes the wedge piece 3 to move.

[0034] In some embodiments, a magnet is provided at one end of the wedge nut 5 away from the wedge piece 3, and the wedge nut 5 is connected to the upper and lower ends of the wedge hole through the magnet.

[0035] The connection between the wedge nut 5 and the bottom end of the wedge hole is strengthened by a magnet to prevent the wedge nut 5 from causing the connection between the pressure bolt 1 and the wedge nut 5 to loosen due to its own gravity when the bolt body 4 and the nut 2 are vertically matched, thereby preventing the connection between the bolt body 4 and the nut 2 from loosening.

[0036] In some embodiments, the length of the pressure bolt 1 is smaller than the length of the wedge-shaped hole and larger than the length between the wedge-shaped nut 5 and an end face of the bolt body 4 provided with an external thread, to ensure that before the pressure bolt 1 is matched with the wedge-shaped nut 5, there is no extrusion between the pressure bolt 1 and the wedge-shaped member 3, so that during the process of the thread of the pressure bolt 1 matching with the thread of the wedge-shaped nut 5, the pressure bolt 1 can gradually and completely extend into the wedge-shaped hole.

[0037] In some embodiments, a pair of strain gauges is provided at the connection between the bolt body 4 and the nut 2 .

[0038] When the bolt head of the pressure bolt 1 presses the wedge 3 downward, the bolt body 4 squeezes the nut 2 under the action of the wedge 3. The change of the preload force between the bolt body 4 and the nut 2 is calculated by the deformation of the strain gauge. The torque of the pressure bolt 1 is adjusted according to actual needs to adjust the preload force between the bolt body 4 and the nut 2.

[0039] On the other hand, an embodiment of the present invention discloses a method for adjusting the preload force of an internal wedge bolt. The method uses the internal wedge bolt and includes the following steps:

[0040] S10: Connect the nut 2 to the bolt body 4;

[0041] S20: placing the wedge-shaped member 3 into the wedge-shaped hole;

[0042] S30: insert the threaded end of the pressure bolt 1 through the wedge-shaped piece 3 and into the wedge-shaped hole, rotate the pressure bolt 1 so that the pressure bolt 1 is threadedly matched with the threaded hole, and the pressure bolt 1 pushes the wedge-shaped piece 3 to slide to adjust the preload force of the bolt body.

[0043] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0044] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An internal wedge bolt, characterized in that: include: A bolt body, wherein the outer wall of the bolt body is provided with an external thread, a nut is connected to the outside of the bolt body, a wedge-shaped hole is provided on the end surface of one end of the bolt body provided with the external thread and extends inwardly therefrom, and a threaded hole is provided at the bottom end of the wedge-shaped hole; A wedge-shaped member, wherein the wedge-shaped member is provided with a through hole along its axial direction; A pressure bolt, wherein one end of the pressure bolt is provided with a thread and passes through the through hole and is threadedly connected to the threaded hole. As the threaded engagement length of the pressure bolt and the threaded hole increases, the bolt head of the pressure bolt squeezes the wedge-shaped piece and moves into the wedge-shaped hole, so that the bolt body is provided with an external thread position and is tightened with the nut.

2. The internal wedge bolt according to claim 1, characterized in that A wedge-shaped nut is arranged at the bottom end of the wedge-shaped hole, the threaded hole is arranged on the wedge-shaped nut, and the wedge-shaped nut is fixedly connected to the wedge-shaped hole.

3. The internal wedge bolt according to claim 2, characterized in that A magnet is arranged at one end of the wedge-shaped nut away from the wedge-shaped piece, and the wedge-shaped nut is connected to the upper and lower ends of the wedge-shaped hole through the magnet.

4. The internal wedge bolt according to claim 1, characterized in that A pair of strain gauges is provided at the connection between the bolt body and the nut.

5. A method for adjusting the preload force of an internal wedge bolt, characterized in that: The adjustment method uses the internal wedge bolt according to any one of claims 1 to 4, comprising the following steps: S10: Connect the nut to the bolt body; S20: placing the wedge into the wedge hole; S30: Put the threaded end of the pressure bolt through the wedge-shaped piece and into the wedge-shaped hole, rotate the pressure bolt so that the pressure bolt and the threaded hole are threadedly matched, and the pressure bolt pushes the wedge-shaped piece to slide to adjust the preload force of the bolt body.

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