Locking-mode-selectable lock bolt and nut device

Abstract

A locking-mode-selectable lock bolt and nut device comprises a bolt and a nut, the main fastening nut is arranged on the bolt in a sleeving manner; the fixed locknut is arranged on the bolt in a sleeving manner and is positioned above the main fastening nut; wherein a bolt locking groove is formed in the outer wall of one side of the bolt in the length direction, the section of the bolt locking groove is triangular, an acute angle is formed by two side faces in the bolt locking groove, one side face is arranged in the radial direction of the bolt, and the other side face is an inclined face; mounting through holes are symmetrically formed in two opposite surfaces of the fixed locknut, and a screw hole, a round hole and a square hole are sequentially formed in each mounting through hole from outside to inside; the inner diameter of the round hole is larger than that of the screw hole, and the width of the square hole is smaller than that of the round hole. And the two locking assemblies are respectively inserted into the two mounting through holes of the fixed locknut.

Description

Technical Field

[0001] The present invention relates to the technical field of bolt connection, and in particular to a bolt and nut device with optional locking mode to prevent loosening. Background Art

[0002] When bolts and nuts are connected, a double-nut structure is often used for tightening in conditions with minimal vibration. This is also known as a double-nut locking mechanism. When two double-nuts are tightened, there is constant pressure between them. Any rotation of either nut requires overcoming the friction between the threads. Even if the external load changes, if specialized technical measures are used to prevent the upper nut from loosening, the pressure between the double-nuts remains constant, thus preventing loosening.

[0003] In the prior art, double nut anti-loosening is usually the first to loosen when there is a large vibration, and then the main fastening nut is also loosened, which eventually leads to connection failure. Summary of the Invention

[0004] The purpose of the present invention is to design a bolt and nut anti-loosening device with optional locking mode, which effectively prevents the loosening of the fastening bolts, has a good anti-loosening effect, and can be widely used in the connection of equipment with large vibrations.

[0005] To achieve the above object, the technical solution of the present invention is:

[0006] A bolt and nut anti-loosening device with optional locking mode, comprising:

[0007] Bolts can be passed through the two connecting plates;

[0008] The main fastening nut is sleeved on the bolt;

[0009] The fixed anti-loosening nut is sleeved on the bolt and located above the main fastening nut; wherein,

[0010] The bolt has an outer wall on one side thereof with a bolt locking groove along its length. The length of the bolt locking groove is less than the thickness of the two connecting plates plus the thickness of the main fastening nut. The cross section of the bolt locking groove is triangular, and the two side surfaces in the bolt locking groove form an acute angle, one of which is arranged along the radial direction of the bolt, and the other side surface is an inclined surface.

[0011] The fixing locknut has two symmetrically arranged mounting holes on two opposite sides thereof, and the mounting holes are sequentially provided with a screw hole, a round hole and a square hole from the outside to the inside; wherein the inner diameter of the round hole is larger than the inner diameter of the screw hole, and the width of the square hole is smaller than the inner diameter of the round hole;

[0012] Two locking assemblies are respectively inserted into the two mounting holes of the fixed anti-loosening nut; the locking assemblies include:

[0013] The one-way locking pin has a front portion that is a triangle that matches the bolt locking groove, a middle portion that is a cube or a cuboid that matches the square hole, and a rear portion that is a first short axis protruding from the center of the rear end face of the cube or cuboid;

[0014] A locking pin screw, the outer diameter of which matches the screw hole, and a second short axis protruding from the center of the front end surface of the locking pin screw, the second short axis being arranged opposite to the first short axis with a gap therebetween;

[0015] The spring is sleeved on the first short shaft and the second short shaft.

[0016] Preferably, the gap between the second short axis and the first short axis is greater than the depth of the bolt locking groove of the bolt, and is also greater than the length of the external thread of the locking pin screw.

[0017] Preferably, the length of the internal thread of the screw hole in the installation through hole of the fixed anti-loosening nut is less than or equal to the length of the external thread of the locking pin screw in the locking assembly.

[0018] In the optional locking method anti-loosening bolt and nut device of the present invention,

[0019] The locking assembly includes a one-way locking pin, a spring, and a locking pin screw. To install it on the fixed anti-loosening nut, first install the one-way locking pin in the square hole with the inclined surface facing the fixed anti-loosening nut, then install the spring on the boss behind the one-way locking pin, and finally screw the locking pin screw into the fixed anti-loosening nut thread. At the same time, the first short axis of the locking pin screw is embedded in the spring. The locking pin screw is screwed into the fixed anti-loosening nut thread until the outer surface is flush with the outer surface of the fixed anti-loosening screw. The distance between the one-way locking pin and the first and second short axes of the locking pin screw is designed to be greater than the depth of the bolt locking groove on the bolt, and also greater than the set thread length of the locking pin screw. The outside of the locking pin screw is provided with a cross slot for screwdrivers.

[0020] The lockable variable thread anti-loosening bolt and nut device of the present invention is characterized in that the position where the locking pin screw enters is used as a selective nut locking method. In the first locking method, when the locking pin screw is flush with the fixed anti-loosening nut, the spring pushes the one-way locking pin to enter the bolt locking groove on the bolt, and the anti-loosening nut can still be rotated normally in the clockwise direction, but the fixed anti-loosening nut cannot be tightened in the reverse direction. In normal use, the fixed anti-loosening nut is tightened, and the one-way locking pin enters the bolt locking groove, locking the bolt and anti-loosening nut. At this time, if the locking pin screw is removed, the spring and one-way locking pin of the locking system can also be removed, and the fixed anti-loosening nut and main fastening nut can now be removed. In the second locking method, after the fixed anti-loosening nut is tightened, the one-way locking pin continues to be screwed into the locking pin screw until the fixed anti-loosening nut thread is completely unscrewed. At this time, the locking pin screw cannot be removed, and the one-way locking pin is permanently fixed in the bolt locking groove, permanently locking the bolt and anti-loosening nut. The present invention can effectively prevent the bolts from loosening, has a good effect in preventing the connection from loosening, and can be widely used for connecting equipment with large vibrations.

[0021] Compared with the prior art, the advantages of the present invention are:

[0022] The present invention adopts the change of the thread position of the threaded pin and the one-way locking pin of the locking system to embed the anti-loosening nut into the bolt locking groove of the bolt, so that the anti-loosening nut and the bolt achieve an anti-loosening structure; at the same time, the locking pin is screwed into the fixed anti-loosening nut position, so that the fixed anti-loosening nut is in a locked state, a disassembled state and a permanently locked state.

[0023] The present invention has a simple structure, effectively prevents the fastening bolts from loosening, has a good effect of preventing connection loosening, has a low production cost, and can be widely used for connecting equipment with large vibrations. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A front view of an embodiment of the present invention;

[0025] Figure 2 This is a schematic structural diagram of Example 1 of the present invention;

[0026] Figure 3 This is a schematic structural diagram of Example 2 of the present invention;

[0027] Figure 4 This is a schematic structural diagram of a bolt in an embodiment of the present invention;

[0028] Figure 5 is a top view of a bolt in an embodiment of the present invention;

[0029] Figure 6 for Figure 5 AA section view;

[0030] Figure 7 This is a schematic structural diagram of a fixed anti-loosening nut according to an embodiment of the present invention;

[0031] Figure 8 for Figure 7 BB cross-sectional view;

[0032] Figure 9 for Figure 7 CC cross-sectional view;

[0033] Figure 10 Schematic diagram of the enlarged structure of the locking assembly in an embodiment of the present invention. DETAILED DESCRIPTION

[0034] See also Figures 1 to 10 The optional locking method anti-loosening bolt and nut device of the present invention includes:

[0035] Bolt 1 can be passed through the two connecting plates 100;

[0036] The main fastening nut 2 is sleeved on the bolt 1;

[0037] The fixed anti-loosening nut 3 is sleeved on the bolt 1 and is located above the main fastening nut 2; wherein,

[0038] The bolt 1 has a bolt locking groove 11 formed on its outer wall along its length. The length L11 of the bolt locking groove 11 is less than the thickness of the two connecting plates 100 plus the thickness of the main fastening nut 2. The cross-section of the bolt locking groove 11 is triangular, and the two side surfaces of the bolt locking groove 11 form an acute angle, one of which is arranged along the radial direction of the bolt 1, and the other side is an inclined surface.

[0039] The fixing locknut 3 has two symmetrically arranged mounting holes 31 and 31' on two opposite surfaces. The mounting hole 31 (taking the mounting hole 31 as an example, the same below) is provided with a screw hole 311, a round hole 312 and a square hole 313 from the outside to the inside. The inner diameter of the round hole 312 is larger than that of the screw hole 311, and the width of the square hole 313 is smaller than that of the round hole 312.

[0040] The two locking components 4 and 4' are respectively inserted into the two mounting holes 31 of the fixing nut 3; the locking component 4 (taking the locking component 4 as an example, the same below) includes:

[0041] The one-way locking pin 41 has a front portion formed as a triangular body 411 that matches the bolt locking groove 11, a middle portion formed as a cube 412 or a rectangular parallelepiped that matches the square hole 313, and a rear portion formed as a first short axis 413 protruding from the center of the rear end face of the cube 412 or the rectangular parallelepiped;

[0042] The outer diameter of the locking pin screw 42 matches the screw hole 311. A second short axis 421 is protruded from the center of the front end surface of the locking pin screw 42. The second short axis 421 is arranged opposite to the first short axis 413, maintaining a gap H. Preferably, the internal thread length L311 of the screw hole 311 is the same as or less than the external thread length L42 of the locking pin screw 42.

[0043] The spring 43 is sleeved on the first short shaft 413 and the second short shaft 421 .

[0044] Preferably, the gap H between the second short axis 421 and the first short axis 413 is greater than the depth h of the bolt locking groove 11 of the bolt 1 , and is also greater than the length L42 of the external thread of the locking pin screw 42 .

[0045] When in use, tighten the main fastening nut 2 and the bolt 1 on the equipment or facility, and after meeting the pre-tightening requirements, screw the fixed anti-loosening nut 3 completely into the bolt 1 until one of the locking components 4 holes of the fixed anti-loosening nut 3 overlaps with the bolt locking groove 11, install the one-way locking pin 41 in the square hole with the inclined surface facing the fixed anti-loosening nut 3, and then install the spring on the first short axis at the rear of the one-way locking pin 41, and finally screw the locking pin screw 42 into the thread of the fixed anti-loosening nut 3, and at the same time, the second short axis of the locking pin screw 42 is embedded in the spring; wait until the hole position of the other locking component 4' overlaps with the bolt locking groove 11, and install another set of locking components 4 as described above. The distance H between the first and second short axes of the one-way locking pin 41 and the locking pin screw 42 is designed to be greater than the depth h of the bolt locking groove 11 opened by the bolt 1. The one-way locking pin 41 ensures that the fixed anti-loosening nut 3 is screwed in normally, and continues to screw in the fixed anti-loosening nut 3 until the fixed anti-loosening nut 3 is tightened in place. The one-way locking pin 41 of one set of locking assemblies 4 is embedded in the bolt locking groove 11. At this time, the fixed anti-loosening nut 3 will not rotate due to vibration and external force, ensuring that the bolt and nut are locked.

[0046] To remove the bolt and nut mechanism, first unscrew the locking pin screw 42 of the locking assembly 4, then remove the spring 43 and the one-way locking pin 41; then remove the other set of locking assemblies 4. The fixed anti-loosening nut 3 can be unscrewed, and finally remove the main fastening nut 2.

[0047] If the bolt and nut need to be locked permanently on site and not removed later, the locking pin screw 42 of the locking assembly 4 at the locking position must be screwed in first until the locking pin screw 42 is completely screwed into the internal thread of the locking screw that fixes the anti-loosening nut 3. At this time, the locking pin screw 42 cannot be screwed out, and the one-way locking pin 41 at this position is permanently embedded in the bolt locking groove 11 (see Figure 3 ), so that the fixed anti-loosening nut 3 cannot be rotated, ensuring that the bolt and nut are locked.

Claims

1. A bolt and nut anti-loosening device with optional locking mode, comprising: Bolts can be passed through the two connecting plates; The main fastening nut is sleeved on the bolt; The fixed anti-loosening nut is sleeved on the bolt and is located above the main fastening nut; its characteristics are: The bolt has an outer wall on one side thereof with a bolt locking groove along its length. The length of the bolt locking groove is less than the thickness of the two connecting plates plus the thickness of the main fastening nut. The cross section of the bolt locking groove is triangular, and the two side surfaces in the bolt locking groove form an acute angle, one of which is arranged along the radial direction of the bolt, and the other side surface is an inclined surface. The fixing locknut has two symmetrically arranged mounting holes on two opposite sides thereof, and the mounting holes are sequentially provided with a screw hole, a round hole and a square hole from the outside to the inside; wherein the inner diameter of the round hole is larger than the inner diameter of the screw hole, and the width of the square hole is smaller than the inner diameter of the round hole; Two locking assemblies are respectively inserted into the two mounting holes of the fixed anti-loosening nut; the locking assemblies include: The one-way locking pin has a front portion that is a triangle that matches the bolt locking groove, a middle portion that is a cube or a cuboid that matches the square hole, and a rear portion that is a first short axis protruding from the center of the rear end face of the cube or cuboid; A locking pin screw, the outer diameter of which matches the screw hole, and a second short axis protruding from the center of the front end surface of the locking pin screw, the second short axis being arranged opposite to the first short axis with a gap therebetween; The spring is sleeved on the first short shaft and the second short shaft.

2. The bolt and nut device with optional locking method for preventing loosening according to claim 1, characterized in that: The gap between the second short axis and the first short axis is greater than the depth of the bolt locking groove of the bolt, and is also greater than the length of the external thread of the locking pin screw.

3. The bolt and nut device with optional locking method for preventing loosening according to claim 1, characterized in that: The length of the internal thread of the screw hole in the installation through hole of the fixed anti-loosening nut is less than or equal to the length of the external thread of the locking pin screw in the locking assembly.

Images