Bolt locking device

Abstract

The utility model relates to the technical field of bolt looseness prevention, in particular to a bolt looseness prevention device which comprises a bolt, the bolt is sequentially sleeved with a flat gasket and a nut after penetrating through a workpiece, a positioning hole is formed in the bolt in the radial direction in a penetrating mode, one part of the positioning hole is shielded by the nut, and the other part of the positioning hole is connected with a positioning column in an inserted mode. The positioning column penetrates through the bolt and is clamped on the other side, away from the flat gasket, of the nut, so that the nut cannot move; the positioning column comprises an upper inclined wedge and a lower inclined wedge from top to bottom, the upper surface of the upper inclined wedge is attached to the positioning hole, the lower surface of the lower inclined wedge is close to the nut, the lower surface of the upper inclined wedge and the upper surface of the lower inclined wedge are attached to each other, and the attaching face is an inclined face. The locking device is strong in locking force, and cannot loosen even if bearing large vibration.

Description

Technical Field

[0001] The utility model relates to the technical field of bolt loosening prevention, in particular to a bolt loosening prevention device. Background Art

[0002] A bolt is a commonly used fastener, which consists of a head and a screw rod with external threads. It is usually used in combination with a nut to fasten parts with through holes and is easy to disassemble. It is widely used in daily life and industrial manufacturing. Due to the influence of the torque in the thread pair, relative displacement will occur between the contact surfaces, resulting in the gradual loosening of the bolt or nut. As Figure 1 shown, the existing bolt loosening prevention structure consists of a bolt, a flat gasket, a nut and a split pin. After the bolt is assembled, a hole is drilled in the bolt and the nut, and then the split pin is driven in for fixation.

[0003] The existing bolt loosening prevention structure in the above form has the following problems:

[0004] First, the cross-section of the split pin is small and the locking force it can bear is low; second, there is a gap between the hole and the split pin, and the split pin is prone to deformation and loosening after a long time. The bolt loosening prevention effect is not good and does not meet the needs of daily production. Summary of the Invention

[0005] In order to solve the problems of low locking force of the existing bolt loosening prevention structure in the form of split pins and easy deformation and loosening of the split pins during long-term use, the utility model provides a bolt loosening prevention device with strong locking force, which will not loosen even under large vibrations.

[0006] In order to achieve the above purpose, the technical solution of the utility model is:

[0007] A bolt loosening prevention device includes a bolt. After the bolt passes through a workpiece, a flat gasket and a nut are sleeved in sequence. A positioning hole is radially penetrated through the bolt. Part of the positioning hole is shielded by the nut, and the other part is inserted with a positioning post. The positioning post passes through the bolt and is stuck on the other side of the nut away from the flat gasket, so that the nut cannot displace;

[0008] The positioning post includes an upper wedge and a lower wedge from top to bottom. The upper surface of the upper wedge fits the positioning hole, the lower surface of the lower wedge abuts against the nut, the lower surface of the upper wedge and the upper surface of the lower wedge fit each other, and the fitting surface is an inclined surface. Thus, the height of the positioning post can be controlled by moving the positions of the upper and lower wedges.

[0009] Further, the upper wedge and the lower wedge have the same length. When in use, the upper wedge and the lower wedge are inserted from both sides respectively, and the bolt is located in the middle position between the upper wedge and the lower wedge, and the force is more stable.

[0010] Further, the angle between the mating surface of the upper wedge and the lower wedge and the horizontal plane is between 2° and 5°. The frictional force between the upper wedge and the lower wedge is large, preventing the upper wedge and the lower wedge from slipping.

[0011] Further, the positioning hole is an oval hole, and the upper surface of the upper wedge matches the oval hole. This facilitates the insertion of the upper wedge.

[0012] Further, the width of the positioning hole is not greater than one-fourth of the diameter of the bolt rod. This ensures the depth of the positioning hole in the bolt, increases the contact area between the upper and lower wedges and the inner wall of the positioning hole, making the connection more stable.

[0013] Further, the height of the positioning hole is greater than the height of the nut. This increases the area of the upper and lower wedges within the positioning hole, facilitating hammering.

[0014] By the above technical solution, the beneficial effects of the present utility model are as follows:

[0015] In the present utility model, a positioning post is provided outside the nut. The positioning post passes through the bolt to hold the nut in place and prevent it from displacing. The positioning post includes an upper wedge and a lower wedge. The upper wedge and the lower wedge are of equal length and opposite in direction. The lower surface of the upper wedge and the upper surface of the lower wedge are mutually fitted, and the mating surface is inclined. Thus, the height of the positioning post can be controlled by moving the relative positions of the upper and lower wedges, filling the positioning hole with the positioning post, and further preventing the nut from loosening.

[0016] Compared with the existing bolt anti-loosening structure composed of split pins, the cross-section of the upper and lower wedges is large, and there is no gap between the wedges and the nut. Even under large vibrations, it will not loosen, making it particularly suitable for nut anti-loosening of large vibration equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic diagram of the original bolt anti-loosening structure;

[0018] Figure 2 is the front view of the present utility model;

[0019] Figure 3 is the side view of the present utility model;

[0020] Figure 4 is the sectional view along Figure 3 line A-A in

[0021] In the drawings, the reference numerals are: 1 is the bolt, 11 is the positioning hole, 2 is the flat washer, 3 is the nut, 41 is the upper wedge, 42 is the lower wedge, and 5 is the workpiece. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] The present utility model will be further described below in conjunction with the drawings and specific embodiments:

[0023] AsFigures 2 to 4 As shown in the figure, this embodiment provides a bolt loosening prevention device, including a bolt 1. After the bolt 1 passes through a workpiece 5, a flat gasket 2 and a nut 3 are sequentially sleeved on the bolt 1. A positioning hole 11 is radially penetrated through the bolt 1. A part of the positioning hole 11 is shielded by the nut 3, and the other part is inserted with a positioning post. The positioning post passes through the bolt 1 and is stuck on the other side of the nut 3 away from the flat gasket 2, so that the nut 3 cannot be displaced.

[0024] In order to prevent the nut 3 from loosening, two nuts 3 are sleeved on the bolt 1. The first friction surface is between the nut 3 and the fastened workpiece 5, and the second friction surface is between the nut 3 and the nut 3. When the workpiece 5 is subjected to impact and vibration loads, the friction force of the first friction surface decreases, but the friction force of the second friction surface increases, thereby preventing the nut 3 from loosening.

[0025] In order to ensure the stable insertion of the positioning post in the positioning hole 11, the width of the positioning hole 11 is not greater than one-fourth of the rod diameter of the bolt 1; the height of the positioning hole 11 is greater than the height of the nut 3, and the positioning hole 11 is perpendicular to the central axis of the bolt 1.

[0026] The positioning post includes an upper wedge 41 and a lower wedge 42 from top to bottom. The upper wedge 41 and the lower wedge 42 are correspondingly arranged. The upper wedge 41 and the lower wedge 42 have the same length and opposite directions. During installation, the upper wedge 41 and the lower wedge 42 are inserted into the positioning hole 11 from both sides of the bolt 1 respectively.

[0027] In order to lock the nut, the upper surface of the upper wedge 41 fits the positioning hole 11, the lower surface of the lower wedge 42 is close to the nut 3, the lower surface of the upper wedge 41 and the upper surface of the lower wedge 42 are mutually attached, and the attachment surface is an inclined surface. Thus, the height of the positioning post can be controlled by moving the positions of the upper and lower wedges 42, and further the nut 3 is locked so that it cannot be displaced.

[0028] Preferably, the included angle between the attachment surface of the upper wedge 41 and the lower wedge 42 and the horizontal plane is between 2° and 5°. Within this included angle range, it is not easy for the upper wedge 41 and the lower wedge 42 to slip off each other.

[0029] As an implementable manner, the positioning hole 11 is a waist-shaped hole. The upper surface of the upper wedge 41 matches the waist-shaped hole and is arc-shaped. The lower surface of the lower wedge 42 is flat. When the upper wedge 41, the lower wedge 42 and the nut 3 are locked, the lower surface of the lower wedge 42 closely adheres to the nut 3. The upper surface of the upper wedge 41 is arc-shaped, and its resistance to entering the positioning hole 11 is smaller. At the same time, it avoids damage to the material caused by sharp corners. After the upper wedge 41 is knocked in, the contact area between the arc-shaped surface and the positioning hole 11 is large, so that more friction force is generated, and when the upper wedge 41 is subjected to a lateral force or a tensile force, it is more difficult to loosen or pull out.

[0030] During use, the flat gasket 2 and the nut 3 are successively sleeved onto the bolt 1. The inclined surfaces of the upper wedge 41 and the lower wedge 42 are made to correspond, and they are respectively inserted into the positioning holes 11 from both sides. By adjusting the positions of the upper wedge 41 and the lower wedge 42, the heights of the upper wedge 41 and the lower wedge 42 in the positioning holes 11 can be adjusted. After the upper wedge 41 and the lower wedge 42 fill the positioning holes 11, the upper wedge 41 is hammered until the upper wedge 41 and the lower wedge 42 are in interference fit in the positioning holes 11 and there is no gap between the lower wedge 42 and the nut 3. Then, the upper wedge 41 and the lower wedge 42 are welded together, thus realizing the function of preventing the nut 3 from loosening.

[0031] Compared with the bolt loosening prevention structure composed of existing split pins, the cross-sections of the upper and lower wedges are large, and the locking force they bear is more than 10 times that of the split pin. There is no gap between the wedge and the nut, and it will not loosen even when subjected to large vibrations, which is especially suitable for preventing the nuts of large vibrating equipment from loosening.

[0032] The above-described embodiments are only the preferred embodiments of the present invention and do not limit the scope of implementation of the present invention. Therefore, any equivalent changes or modifications made according to the structures, features, and principles described in the scope of the present invention patent shall be included within the scope of the present invention's patent application.

Claims

1. A bolt loosening prevention device, comprising a bolt (1), wherein the bolt (1) passes through a workpiece (5) and is sequentially sleeved with a flat gasket (2) and a nut (3), characterized in that, A positioning hole (11) is radially penetrated through the bolt (1). Part of the positioning hole (11) is shielded by the nut (3), and the other part is inserted with a positioning post. The positioning post passes through the bolt (1) and is stuck on the other side of the nut (3) away from the flat gasket (2), so that the nut (3) cannot be displaced. The positioning post includes an upper wedge (41) and a lower wedge (42) from top to bottom. The upper surface of the upper wedge (41) fits the positioning hole (11). The lower surface of the lower wedge (42) is close to the nut (3). The lower surface of the upper wedge (41) and the upper surface of the lower wedge (42) fit each other, and the fitting surface is an inclined surface.

2. The bolt loosening prevention device according to claim 1, characterized in that, The upper wedge (41) and the lower wedge (42) have the same length.

3. A bolt loosening prevention device according to claim 1, characterized in that, The included angle between the fitting surface of the upper wedge (41) and the lower wedge (42) and the horizontal plane is between 2° and 5°.

4. A bolt loosening prevention device according to claim 1, characterized in that, The positioning hole (11) is an oval hole, and the upper surface of the upper wedge (41) matches the oval hole.

5. A bolt loosening prevention device according to claim 1, characterized in that, The width of the positioning hole (11) is not greater than one-fourth of the diameter of the bolt (1) rod.

6. A bolt loosening prevention device according to claim 1, characterized in that, The height of the positioning hole (11) is greater than the height of the nut (3).

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