CN118224171A

CN118224171A - Anti-loose assembly

Info

Publication number: CN118224171A
Application number: CN202310104191.5A
Authority: CN
Inventors: 李琪; 袁新璐; 余磊
Original assignee: Lhasa Yuzhixin Technology Co ltd
Current assignee: Lhasa Yuzhixin Technology Co ltd
Filing date: 2023-02-13
Publication date: 2024-06-21

Abstract

The invention discloses a locking assembly, which comprises: the nut and the gasket are regular hexagons with the side length Lx, a plurality of wedge blocks are arranged on the nut and the gasket, the wedge blocks are mutually embedded on the contact surfaces of the nut and the gasket, the wedge blocks comprise a first wedge surface and a second wedge surface, the first wedge surface is an inclined surface with the direction opposite to the direction of the inclined surface of the thread, the second wedge surface is a step elevation with the vertical height L adjacent to the first wedge surface, when the gasket rotates around the fastening direction of the nut, the pretightening force is increased to the maximum degree, when the gasket rotates around the loosening direction of the nut, the locking component is stably self-locked as a target, the optimal value range of the wedge angle of the wedge block is obtained, and the locking performance of the locking component is enhanced.

Description

Anti-loose assembly

The invention belongs to the technical field of anti-loosening fasteners, and particularly relates to an anti-loosening assembly.

Background

Nuts and gaskets are commonly used fasteners, and the nuts and gaskets are commonly matched for use, so that under the conditions of high-frequency and large-amplitude vibration or impact, the nuts can rotate relative to the bolts, and the fastened objects are loosened and shifted, namely the fastened objects are failed. For this reason, anti-loosening fasteners have been studied, and one of the directions of research is to use wedge-shaped block structures to form self-locking for anti-loosening purposes, and many products of this type are currently available.

Chinese patent application CN201811493116.8 discloses a fastening component, through setting up the wedge interlock tooth of interlock each other on gasket, the nut contact surface, through the cooperation of interlock tooth, prevent the relative rotation between gasket, the nut, reach the purpose of preventing loosening. As shown in fig. 1 of patent CN201811493116.8, the heights of the wedge-shaped engaging teeth on the nut are sequentially increased along the rotation direction of the nut during fastening, that is, the inclination direction of the wedge-shaped block is the same as the rotation direction of the thread (e.g., the thread is a right-handed thread with a right-high left-low in fig. 1, and the engaging teeth also have a right-high left-low shape). However, when the nut and gasket assembly is used, the gasket tends to rotate after vibrating, and when the gasket rotates around the nut fastening direction (considered as positive direction), the inclined surfaces of the nut and the gasket, which are in contact with each other, relatively slide to give smaller fastening component force to the nut, which is beneficial to increasing the fastening effect, which is hoped to be seen by us; however, when the washer rotates reversely, the washer can give a very large component force to the nut to push the nut to rotate and loosen because the washer and the washer are completely matched and have vertical contact in the rotation direction and have no relative sliding space, which is undesirable, however, the rotation direction and the frequency of the washer cannot be controlled, and the washer often exist in two directions simultaneously, which leads to failure of the anti-loosening fastener.

In order to solve the above problems, the applicant proposes a locking nut and washer assembly, see chinese patent application CN202111429659.5, in which the height of the wedge on the nut decreases in the nut tightening rotation direction, i.e. the inclination direction of the wedge is opposite to the thread rotation direction. So that when the gasket rotates around the nut tightening direction under the reciprocating vibration, the nut is screwed, which is beneficial to anti-loose. When the gasket rotates reversely around the nut fastening direction, the gasket can slide relative to the nut, when the nut rotates relatively with the gasket, the lower end face of the wedge-shaped block of the nut and the upper end face of the wedge-shaped block of the gasket slide relatively and then are in dislocation compaction contact, and finally self-locking is formed, so that fastening failure caused by rotation of the gasket along the loosening direction in the traditional wedge-shaped anti-loosening assembly is overcome.

However, for the anti-loose assembly in CN202111429659.5, the applicant found in further practice that it also had the following problems: (1) The oblique direction of the wedge block is opposite to the screwing direction of the screw thread, so that a foundation condition of self-locking wedging after the nut and the gasket slide relatively when the gasket rotates along the loosening direction is formed. However, when the fastener is in service, the external load is complex and changeable, the rotation of the gasket under the vibration effect is in an alternating state, namely the amplitude and the direction of each rotation are different, in the process, the nut and the gasket can not enter a self-locking compaction state along the wedge block at a delayed time, and multiple and reciprocating relative sliding still exists between the nut and the gasket, so that the nut is loosened and the fastening is invalid. (2) In the reciprocating vibration process, when the gasket rotates around the nut fastening direction, the pretightening force caused by screwing the nut is increased slightly, the pretightening force is insufficient to resist loosening, and the movement of the gasket around the nut fastening direction is not effectively utilized.

For the self-locking condition of the wedge-shaped anti-loosening assembly, in the prior art, as in CN201721641957.X and CN201921281731.2, the wedge angle of the wedge-shaped block is simply set to be larger than the lead angle of the thread, the friction force of the nut and the gasket in service is not considered, the friction force is a key factor of maintaining self-locking of the gasket and the nut, and the setting of the wedge angle neglecting the friction force often has the adverse effects that the wedge angle is too small to effectively wedge, or the sliding is easily generated due to the too large wedge angle. In addition, the self-locking condition is not suitable for the anti-loosening component with the wedge block inclination direction opposite to the thread rotation direction due to different stress states in service.

Therefore, (1) how to ensure that the anti-loose assembly with the inclination direction of the wedge block and the rotation direction of the screw thread are in a self-locking state rapidly, stably and reliably. (2) How to effectively utilize the rotation of the gasket along the nut fastening direction in vibration, improve pretightening force and resist loosening is a problem to be solved in the prior art.

Disclosure of Invention

In order to solve the problems in the prior art, the invention aims to provide a locking assembly which can quickly, stably and reliably enter a self-locking state, and meanwhile, the rotation of a gasket along the tightening direction of a nut in reciprocating vibration is effectively utilized, so that the pretightening force is enhanced, and the possibility of loosening a fastener is reduced.

In order to achieve the above object, the present invention provides the following technical solutions:

a locking assembly, comprising: the nut and the gasket are regular hexagons with the side length Lx, a plurality of wedge blocks are arranged on the nut and the gasket, the wedge blocks are mutually embedded on the contact surfaces of the nut and the gasket, the wedge blocks comprise a first wedge surface and a second wedge surface, the first wedge surface is an inclined surface with the direction opposite to that of the inclined surface of the thread, the second wedge surface is a step elevation with the vertical height L adjacent to the first wedge surface, and the nut and the gasket are characterized in that the acute angle included angle between the inclined surface and the horizontal plane is a wedge angle alpha, and the wedge angle alpha is in a value range of:

arctan(L/Lx)<α<arctan(2L/Lx)

wherein: alpha is a wedge angle; l is the vertical height of the elevation of the step; lx is the side length of the nut and the gasket.

Preferably, the wedge angle α simultaneously satisfies the following relationship:

wherein: alpha is a wedge angle; beta is the thread lead angle; k0 is the friction coefficient between the gasket and the surface of the fastened object; k1 is the thread friction coefficient; k2 is the contact surface friction coefficient between the wedge blocks.

Preferably, the vertical height of the step elevation is the vertical distance between the highest point and the lowest point of the wedge block where the step elevation is located.

Preferably, the range of the friction coefficient k1 of the thread is 0.1< k1<0.2, and the range of the friction coefficient k2 of the contact surface between the wedge blocks is 0.1< k2<0.2.

Preferably, the first wedge surface of the wedge block on the nut and the first wedge surface of the wedge block on the gasket are arranged vertically opposite and are mutually attached, and the second wedge surface of the wedge block on the nut and the second wedge surface of the wedge block on the gasket are arranged horizontally opposite and are mutually attached.

Preferably, the vertical height of the step elevation formed by the second wedge surface of the wedge block on the nut is equal to that of the step elevation formed by the second wedge surface of the wedge block on the gasket, and the inclined plane wedge angle alpha formed by the first wedge surface of the wedge block on the nut is equal to that of the first wedge surface of the wedge block on the gasket.

Preferably, the surface of the pad contacting the fastened object is flat.

Preferably, the number of wedge blocks on the nut and the number of wedge blocks on the washer are 3 or 6.

Compared with the prior art, the anti-loosening assembly provided by the invention has the following beneficial technical effects:

1. The invention aims at maximizing the pretightening force when the gasket rotates in the screwing direction of the nut in vibration, and determines the value range of the wedge angle alpha of the wedge block according to the vertical height of the step elevation and the side length of the nut and the gasket. After the gasket pushes the nut to screw down through the step elevation, the inclined surface of the lower end surface of the wedge block slides along the inclined surface of the upper end surface of the wedge block due to the existence of the wedge angle in a specific range, and the wedge blocks can be wedged to the greatest extent so as to increase the pretightening force and resist loosening.

2. According to the invention, when the gasket rotates along the loosening direction of the nut, the nut and the gasket slide relatively to form wedging self-locking, the direct and key factors of maintaining self-locking of the fastener, namely friction force, are taken as main considerations, and the wedge angle value range of the wedge block is accurately calculated according to the friction coefficient between threads, the friction coefficient between the wedge blocks, the friction coefficient between the gasket and the surface of the fastened object and the thread lift angle. When the gasket is rotated in a loosening direction, the gasket and the nut slide along the wedge-shaped block with a specific wedge angle so as to quickly, stably and reliably enter a self-locking state, the nut and the gasket are mutually pressed, relative sliding does not occur, and further loosening is avoided. The problem that the wedge-shaped anti-loose assembly is difficult to effectively self-lock in the service process in the prior art is solved. The self-locking condition of the anti-loosening component suitable for the inclination direction of the wedge block and the reverse rotation direction of the thread is obtained.

3. According to the invention, the pre-tightening force is increased to the greatest extent when the gasket rotates along the nut tightening direction, and the stable self-locking is adopted as a target when the gasket rotates along the nut loosening direction, so that the corresponding value range of the wedge angle of the wedge-shaped block inclined surface is respectively determined, and the two values are crossed to obtain the optimal value range of the wedge angle, thereby effectively preventing the anti-loosening assembly from losing efficacy in reciprocating vibration.

4. Proper wedge blocks are arranged, so that proper contact stress is obtained, abrasion is not easy, a better mode effect can be brought, and meanwhile, the difficulty of a production process is reduced.

5. The surface of the gasket contacted with the fastened object is smooth, and structures such as small teeth and the like are not arranged, so that uneven stress caused by the arrangement of the small teeth on the lower surface of the gasket is avoided, the anti-loosening effect is influenced, and the surface of the fastened object is prevented from being damaged by the gasket.

Drawings

FIG. 1 is a schematic view of the overall structure of a locking assembly;

FIG. 2 is a schematic view of a wedge on the anti-lock assembly;

FIG. 3 is a schematic view of a nut;

FIG. 4 is a schematic diagram of a gasket;

FIG. 5 is a schematic view of the working state structure of the locking assembly;

fig. 6 is a wedge expansion schematic.

Wherein the reference symbols in the figures have the following meanings:

1. a nut; 2. a gasket; 3. a single-head bolt; 4. a fastened object; 5. wedge blocks; 6. a first wedge surface; 7. and a second wedge surface.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. It will be apparent that the described embodiments are some, but not all, embodiments of the invention.

Thus, the following detailed description of the embodiments of the invention is not intended to limit the scope of the invention, as claimed, but is merely representative of some embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It should be noted that, under the condition of no conflict, the embodiments of the present invention and the features and technical solutions in the embodiments may be combined with each other.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.

In the description of the present invention, it should be noted that, the terms "upper", "lower", and the like indicate an azimuth or a positional relationship based on the azimuth or the positional relationship shown in the drawings, or an azimuth or a positional relationship conventionally put in use of the inventive product, or an azimuth or a positional relationship conventionally understood by those skilled in the art, such terms are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the apparatus or element to be referred must have a specific azimuth, be constructed and operated in a specific azimuth, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like, are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.

As shown in fig. 1 to 6, the invention provides a locking assembly, when the locking assembly is used, one end of a single-head bolt 3 passes through a middle through hole of a fastened object 4, a gasket 2 is sleeved on the single-head bolt 3, and then the gasket 2 is compressed by a nut 1.

The locking subassembly includes: the nut 1 and the gasket 2 are regular hexagons with Lx side lengths, the nut 1 and the gasket 2 are provided with a plurality of wedge blocks 5, the wedge blocks 5 are mutually embedded on contact surfaces of the nut 1 and the gasket 2, the wedge blocks 5 comprise a first wedge surface 6 and a second wedge surface 7, the first wedge surface 6 is an inclined surface with the direction opposite to that of a thread inclined surface, the second wedge surface 7 is a step elevation adjacent to the first wedge surface 6, the vertical height of the step elevation is L, the vertical height of the step elevation is the vertical distance between the highest point and the lowest point of the wedge block 5 where the step elevation is located, and the acute angle included angle between the inclined surface and the horizontal plane is the wedge angle alpha.

When the vibration middle gasket 2 rotates towards the tightening direction of the nut 1, the maximum pretightening force is increased, and the value range of the wedge angle alpha is determined according to the vertical height L of the step elevation 5 and the side length Lx of the nut 1 and the gasket 2, wherein the value range is as follows:

arctan(L/Lx)<α<arctan(2L/Lx)

Wherein: alpha is a wedge angle; l is the vertical height of the elevation of the step; lx is the side length of the nut 1 and the washer 2.

The wedge 5 of nut 1 sets up the lower terminal surface at nut 1, the wedge 5 of gasket 2 sets up in the up end of gasket 2, the lower terminal surface of wedge 5 on the nut 1 is first wedge face 6, the side end face of wedge 5 on the nut 1 is second wedge face 7, the wedge 5 up end on the gasket 2 is first wedge face 6, the side end face of wedge 5 on the gasket 2 is second wedge face 7, the first wedge face 6 on nut 1, the gasket 2 sets up relatively from top to bottom and laminating each other, the nut 1, the second wedge face 7 on the gasket 2 is controlled relatively and is set up and laminating each other. The vertical heights of the step vertical faces formed by the second wedge faces 7 on the nut 1 and the gasket 2 are equal, and the inclined wedge angles alpha formed by the first wedge faces 6 on the nut 1 and the gasket 2 are equal.

When the gasket 2 rotates in the screwing direction of the nut 1 in vibration, the gasket 2 moves the nut 2 to screw down through the step elevation of the second wedge surface 7, the inclined surface of the lower end surface of the wedge block 5 of the nut 1 slides along the inclined surface of the upper end surface of the wedge block 5 of the gasket 2, and the wedge blocks 5 can be wedged to the greatest extent due to the wedge angle alpha in the value range, so that the pretightening force is increased, and looseness is resisted.

Preferably, the wedge-tightening self-locking is formed by relatively sliding the nut 1 and the gasket 2, the friction force is taken as a main consideration factor, a corresponding balance relation is established, and the value range of the wedge angle alpha is determined according to the thread lead angle beta, the friction coefficient k0 between the gasket and the surface of the fastened object, the thread friction coefficient k1 and the contact surface friction coefficient k2 between wedges:

When the wedge angle alpha meets the relation, the lower end face of the wedge block 5 of the nut 1 and the upper end face of the wedge block 5 of the gasket 2 are in dislocation compression contact after sliding relatively, so that the height of the nut 1 and gasket 2 assembly is changed, the anti-loosening assembly rapidly and stably enters a self-locking state, the nut 1 and the gasket 2 are wedged tightly with each other, the gasket 2 does not drive the nut 1 to loosen any more, and a reliable anti-loosening effect is achieved.

According to the invention, the pre-tightening force is increased to the greatest extent when the gasket rotates along the nut tightening direction, and the stable self-locking is adopted as a target when the gasket rotates along the nut loosening direction, so that the corresponding value range of the wedge angle of the wedge-shaped block inclined surface is respectively determined, and the two values are crossed to obtain the optimal value range of the wedge angle, thereby effectively preventing the anti-loosening assembly from losing efficacy in reciprocating vibration.

For example, for a locking component with a regular hexagon side length of 25mm, a step elevation vertical height of 2mm and a thread lift angle of 3.03 degrees, an optimal wedge angle range is obtained by combining a friction coefficient k0 between a gasket and the surface of a fastened object, a thread friction coefficient k1 and an indirect contact surface friction coefficient k2 between wedge blocks, and 5 degrees is taken as a wedge angle value. The anti-loosening assembly is subjected to anti-loosening performance test on a transverse vibration testing machine, the test frequency is 12.5Hz, the vibration times are 1500 times, the residual fastening force/initial fastening force measured after the test is 94.6%, and the anti-loosening performance is good.

Preferably, the screw friction coefficient k1 is in the range of: the range of the friction coefficient k2 between the contact surfaces of the wedge blocks is 0.1< k1< 0.2: 0.1< k2<0.2.

Preferably, the number of wedge blocks on the nut 1 and the number of wedge blocks on the washer 2 are 3 or 6. The more wedge blocks, the smaller the bearing area of the wedge blocks under the same external force, the larger the friction force and pressure on the wedge blocks, and the more serious the abrasion and damage. The selection of the number can obtain proper contact stress and is not easy to wear, so that a better anti-loosening effect can be brought, and meanwhile, the method is also an optimal selection in the aspect of difficulty of a production process.

Preferably, the surface of the gasket 2 contacted with the fastened object 4 is flat, no small teeth and other structures are arranged, uneven stress caused by the small teeth arranged on the lower surface of the gasket 2 is avoided, the anti-loosening effect is affected, and the gasket 2 is prevented from damaging the surface of the fastened object 4.

The above embodiments are only for illustrating the present invention and not for limiting the technical solutions described in the present invention, and although the present invention has been described in detail in the present specification with reference to the above embodiments, the present invention is not limited to the above specific embodiments, and thus any modifications or equivalent substitutions are made to the present invention; all technical solutions and modifications thereof that do not depart from the spirit and scope of the invention are intended to be included in the scope of the appended claims.

Claims

1. A locking assembly, comprising: the nut and the gasket are regular hexagons with the side length Lx, a plurality of wedge blocks are arranged on the nut and the gasket, the wedge blocks are mutually embedded on the contact surfaces of the nut and the gasket, the wedge blocks comprise a first wedge surface and a second wedge surface, the first wedge surface is an inclined surface opposite to the direction of a thread inclined surface, the second wedge surface is a step elevation with the vertical height L adjacent to the first wedge surface, and the nut and the gasket are characterized in that the acute angle included angle between the inclined surface and the horizontal plane is a wedge angle alpha, and the wedge angle alpha is in a value range of:

arctan(L/Lx)<α<arctan(2L/Lx)

2. A locking assembly according to claim 1, wherein the wedge angle α simultaneously satisfies the following relationship:

3. A locking assembly as claimed in claim 1, wherein the vertical height of the step elevation is the vertical distance between the highest point and the lowest point of the wedge.

4. The locking assembly according to claim 2, wherein the range of the thread friction coefficient k1 is 0.1< k1<0.2, and the range of the contact surface friction coefficient k2 between the wedge blocks is 0.1< k2<0.2.

5. The locking assembly of claim 2, wherein the first wedge surface of the wedge on the nut and the first wedge surface of the wedge on the washer are disposed opposite one another and are in abutting engagement with one another, and the second wedge surface of the wedge on the nut and the second wedge surface of the wedge on the washer are disposed opposite one another and are in abutting engagement with one another.

6. A locking assembly as claimed in claim 2, wherein the second wedge surface of the upper nut wedge is equal to the second wedge surface of the upper gasket wedge in vertical height to form a stepped elevation, and the first wedge surface of the upper nut wedge is equal to the first wedge surface of the upper gasket wedge in wedge angle α.

7. A locking assembly as recited in claim 1, wherein the washer has a flat surface in contact with the object to be fastened.

8. A locking assembly as claimed in claim 1, wherein the number of wedge blocks on the nut and the number of wedge blocks on the washer are each 3 or 6.