CN219282231U - Antitheft self-locking firmware - Google Patents

Abstract

The application discloses an anti-theft self-locking fastener, which comprises a bolt and a nut; the nut is of a frustum structure, a plurality of bayonets are formed in the upper side wall of the nut along the circumferential direction, and at least one inclined notch is formed in the lower side wall of the nut; when the nut and the bolt are screwed and tightened, the nut and the bolt are driven to be screwed through the unidirectional cooperation of the special tool and the bayonet until an object to be fastened is fastened; during the screwing process of the nut, the lower part of the nut is extruded by the fastened object to swing towards the closing direction of the oblique incision, so that the lower part of the nut radially extrudes the bolt to form an interference fit. The beneficial effects of this application: the bayonet is arranged on the side wall of the frustum-shaped nut, so that the nut can be screwed only by a special tool, and the anti-theft purpose is achieved. When the nut is tightly combined, the lower part of the nut can swing towards the closing direction of the oblique notch, and then self-locking is realized through radial interference fit between the lower part of the nut and the bolt.

Description

Antitheft self-locking firmware

Technical Field

The application relates to the technical field of fasteners, in particular to an anti-theft self-locking fastener.

Background

Fasteners generally refer to the mating assembly of a nut and a bolt. In order to improve the connection stability between the nut and the bolt and avoid the connection failure caused by the loosening or displacement of the nut, various nuts with self-locking functions are derived from the market, the self-locking function of the nut is realized by extruding the elastic piece, and the elastic piece deforms and extrudes the bolt which is meshed with the inner side for installation when the fastening nut is installed, so that the aim of locking and anti-skid is achieved.

However, the elastic member on the nut may generate deformation defects after multiple extrusion to affect screwing or unscrewing of the nut, so that the service life of the nut is short, and if the service life of the nut is to be prolonged, the performance of the elastic member needs to be improved, and generally, high requirements are imposed on the material and manufacturing process of the elastic member, which may result in an increase in manufacturing cost of the nut. Meanwhile, the existing self-locking nut generally has no anti-theft function.

Disclosure of Invention

One of the purposes of the application is to provide a fastener which is simple in structure and convenient to self-lock and burglary-proof.

In order to achieve at least one of the above objects, the technical scheme adopted in the application is as follows: an anti-theft self-locking fastener comprises a bolt and a nut; the nut is of a frustum structure, a plurality of bayonets are formed in the upper side wall of the nut along the circumferential direction, and at least one inclined notch is formed in the lower side wall of the nut; when the nut and the bolt are screwed and fastened, the nut and the bolt are driven to be screwed through the unidirectional cooperation of a special tool and the bayonet until an object to be fastened is fastened; during the screwing of the nut, the lower part of the nut is pressed by a fastened object to swing towards the closing direction of the oblique incision, so that the lower part of the nut radially presses the bolt to form an interference fit.

Preferably, the included angle of the oblique incision is alpha; the included angle alpha takes a value of 10 deg. -45 deg..

Preferably, a groove is formed in the lower end of the nut, a conical surface is formed in the side wall of the groove, and an included angle between the conical surface and a radial plane of the nut is alpha; the lower end surface of the nut is parallel to the radial plane of the nut when the lower part of the nut swings to be tightened in the direction in which the bevel cut is closed.

Preferably, the number of the oblique cuts is one.

Preferably, the diameter of the threaded hole in the center of the nut is d, and the depth X of the inclined notch extending into the threaded hole is 0 < X < d.

Preferably, the number of the oblique cuts is two, and the oblique cuts are symmetrically arranged on the lower side wall of the nut.

Preferably, the diameter of the threaded hole in the center of the nut is d, and the depth X of the inclined notch extending into the threaded hole is more than 0 and less than d/2.

Preferably, if the height of the nut is H, the height from the oblique notch to the lower end of the nut is 0.1H-0.3H.

Preferably, the height of the nut is H, and the bayonet is communicated with the upper end of the nut, so that the depth of the bayonet along the axial direction is 0.3H-0.6H.

Preferably, the anti-theft self-locking firmware further comprises a gasket; when the nut and the bolt are fastened, the gasket is suitable for being contacted with a fastened object, and then the lower end of the nut is pressed by the gasket to swing towards the closing direction of the oblique incision.

Compared with the prior art, the beneficial effect of this application lies in:

the nut is arranged to be of a frustum structure, and the plurality of bayonets are arranged on the side wall of the upper portion of the nut along the circumferential direction, so that screwing of the nut can only be carried out through matching of a special tool and the bayonets, and the anti-theft purpose is achieved. Simultaneously, through set up the inclined notch in the lower part of nut to when the nut is tight, the lower part of nut can swing to the closed direction of inclined notch, and then realizes the auto-lock through the radial interference fit of nut lower part and bolt.

Drawings

Fig. 1 is a schematic diagram of the overall structure of the present utility model.

Fig. 2 is a schematic structural view of one embodiment of the nut of the present utility model.

Fig. 3 is a schematic cross-sectional view of the nut of the embodiment of fig. 2 in accordance with the present utility model.

Fig. 4 is a schematic diagram of the present utility model in a state of being fastened together.

Fig. 5 is a schematic view of the nut of the embodiment of fig. 2 in the present utility model when tightened.

Fig. 6 is a schematic view of another embodiment of the nut of the present utility model.

Fig. 7 is a schematic view of the nut of the embodiment of fig. 6 in the present utility model when tightened.

In the figure: nut 100, bayonet 110, bevel 120, first side 121, second side 122, groove 130, tapered surface 131, bolt 200, spacer 300.

Detailed Description

The present application will be further described with reference to the specific embodiments, and it should be noted that, on the premise of no conflict, new embodiments may be formed by any combination of the embodiments or technical features described below.

In the description of the present application, it should be noted that, for the azimuth terms such as terms "center", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., the azimuth and positional relationships are based on the azimuth or positional relationships shown in the drawings, it is merely for convenience of describing the present application and simplifying the description, and it is not to be construed as limiting the specific protection scope of the present application that the device or element referred to must have a specific azimuth configuration and operation, as indicated or implied.

It should be noted that the terms "first," "second," and the like in the description and in the claims of the present application are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order.

One of the preferred embodiments of the present application, as shown in fig. 1-7, is a self-locking anti-theft fastener comprising a bolt 200 and a nut 100. The nut 100 has a truncated cone structure, a plurality of bayonets 110 are provided on an upper sidewall of the nut 100 in a circumferential direction, and at least one inclined slit 120 is provided on a lower sidewall of the nut 100. When the nut 100 and the bolt 200 are screwed and tightened, the nut 100 and the bolt 200 can be driven to be screwed with the bolt 200 by being engaged with the bayonet 110 by a special tool and then by unidirectional rotation of the special tool until the nut 100 and the bolt 200 fasten an object to be fastened. In the screwing process of the nut 100, the lower portion of the nut 100 is pressed by a fastened object to swing in the closing direction of the oblique notch 120, so that the lower portion of the nut 100 can radially press the bolt 200 to form interference fit, and self-locking of the nut 100 can be achieved through interference fit of the nut 100 to the bolt 200.

It will be appreciated that conventional nuts 100 and bolts 200 are typically intermittently engaged with each other when the connection is made. In this application, however, the axis of the fitting hole at the center of the lower portion of the nut 100 is offset from the axis of the bolt 200 due to the lower portion of the nut 100 being offset during the screwing with the bolt 200. And in the process of shifting the lower part of the nut 100, one end of the inclined notch 120 of the lower part of the nut 100, which is far away from the center, moves towards the axis direction of the bolt 200, so that the fit hole of the lower part of the nut 100 and the bolt 200 are changed from clearance fit into interference fit, and further, a radial locking moment can be formed on the bolt 200, and the nut 100 and the bolt 200 can be ensured to keep self-locking through the locking moment. Because the lower portion of the nut 100 is deformed plastically, the lower portion of the nut 100 can still ensure the deformation and the self-locking of the bolt 200 after the tightening force of the nut 100 is lost.

It is also understood that when the lower portion of the nut 100 swings in the closing direction of the bevel cut 100 under compression, the self-locking torque can be adjusted by the closing degree of the bevel cut 100. In general, the larger the tightening force applied to the nut 100, the larger the pressing force of the fastened object to the lower portion of the nut 100, and thus the larger the amplitude of the lower portion swing of the nut 100, so that the larger the closing amount of the oblique slit 100, the larger the interference e generated. I.e. the lower part of the nut 100 is dynamic to the self-locking moment of the bolt 200, which can be chosen according to the actual needs. Wherein, when the oblique incision 100 is completely closed, the interference e is maximum, namely the self-locking moment is maximum; meanwhile, the complete closing of the oblique notch 100 can also effectively improve the stability of the using structure of the nut 100. Therefore, for ease of understanding, the following description will be presented with the oblique incision 100 fully closed during self-locking.

In this embodiment, the number of bayonets 110 may be set according to practical needs, for example, as shown in fig. 1, 2 and 4, the number of bayonets 110 is four, and the bayonets 110 are equally spaced along the circumferential direction on the upper side wall of the nut 100.

Specifically, as shown in fig. 1, 2 and 4, all the bayonets 110 are provided with unidirectional openings along the circumferential direction, and the directions of the openings along the circumferential direction of all the bayonets 110 are the same. So that it would not be possible to mate with the opposing two bayonets 110 using a conventional wrench; i.e. the bayonet 110 in this embodiment can only be mated by means of a special tool. Thereby having good anti-theft effect.

It will be appreciated that the specific configuration of the bayonet 110 is varied and only the above-described anti-theft effect is required.

In this embodiment, the upper end of the bayonet 110 may be in communication with the upper end of the nut; the height of the nut 100 may be set to H, and the depth of the bayonet 110 in the axial direction may be 0.3H to 0.6H.

It will be appreciated that since the bayonet 110 is used to mate with a special tool for the screwing of the nut 100, the depth of the bayonet 110 is the mating width with the special tool. Further, in order to secure the fitting stability between the bayonet 110 and the special tool, the depth of the bayonet 110 may be set deep, and may be preferably half the height of the nut 100.

In this embodiment, the height from the oblique notch 120 to the lower end of the nut 100 is 0.1H-0.3H; there is a gap of 0.1H-0.6H between the bevel 120 and the bayonet 110.

It will be appreciated that in order to avoid interference between the machining of the bevel 120 and the bayonet 110, the bevel 120 and the bayonet 110 may be generally spaced apart in the axial direction.

In this embodiment, the anti-theft self-locking fastener of the present application further includes a gasket 300; when the tightening of the nut 100 and the bolt 200 is performed, the washer 300 may be brought into contact with an object to be tightened, and thus the lower end of the nut 100 swings in the closing direction of the diagonal slit 120 by pressing with the washer 300.

It will be appreciated that in order to avoid damage to the object being fastened during tightening of the nut 100, insulation may be provided by the spacer 300. Meanwhile, the compression force bearing area of the nut 100 to be fastened can be increased through the gasket 300, so that damage to the fastened object can be further reduced.

In this embodiment, the included angle of the oblique incision 120 is α; the included angle alpha takes a value of 10 deg. -45 deg..

It should be noted that, the larger the value of the included angle α, the larger the interference e generated with the bolt 200 after the lower portion of the nut 100 swings, that is, the larger the generated self-locking moment. However, if the value of the included angle α is too large, the plastic deformation caused by the swing of the lower portion of the nut 100 is larger, and the lower portion of the nut 100 is likely to be broken. Therefore, the included angle alpha is not easy to be excessively large, and the common value range is 10 degrees to 45 degrees, and the preferable range is 15 degrees to 20 degrees.

In this embodiment, as shown in fig. 3 to 7, a groove 130 is provided at the lower end of the nut 100, a tapered surface 131 is provided on the side wall of the groove 130, and an included angle between the tapered surface 131 and a radial plane of the nut 100 is also α; when the lower portion of the nut 100 swings to be tightened in the direction in which the oblique cut 120 is closed, the lower end surface of the nut 100 is parallel to the radial plane of the nut 100, i.e., the groove 130 of the lower end surface of the nut 100 is not already present.

It can be appreciated that by providing the groove 130 on the lower end surface of the nut 100, deformation resistance of the lower portion of the nut 100 when being extruded can be reduced, that is, deformation of the lower portion of the nut 100 is facilitated, and self-locking of the nut 100 can be facilitated. And the included angle between the conical surface 131 and the radial plane of the nut 100 is at least equal to the included angle between the oblique notch 120, so that in the process of contact extrusion between the lower end of the nut 100 and the gasket 300, the lower end surface of the nut 100 has enough axial compression stroke to drive the lower part of the nut 100 to swing until the oblique notch 120 is closed.

Of course, the included angle between the tapered surface 131 and the radial plane of the nut 100 may be greater than the included angle α, and when the oblique slit 120 is closed, the groove 130 still exists on the lower end surface of the nut 100, so that the lower end surface of the nut 100 makes partial surface contact with the gasket 300, and the extrusion structure of the nut 100 and the gasket 300 is easily unstable.

In the present embodiment, the bevel 120 is formed with a first side 121 and a second side 122; wherein the first side 121 is adjacent to the upper portion of the nut 100 and the second side 122 is adjacent to the lower portion of the nut 100, such that an oblique cut 120 is formed between the first side 121 and the second side 122.

It will be appreciated that, in order to meet the requirement of self-locking the lower portion of the nut 100 to the bolt 200, the first side 121 and the second side 122 are arranged in the following three ways.

Setting mode one: as shown in fig. 3-7, the second side 122 is perpendicular to the axis of the nut 100, i.e., parallel to the radial plane of the nut 100. The first side 121 is inclined to the second side 122 toward the upper portion of the nut 100 such that a desired bevel cut 100 is formed between the first side 121 and the second side 122.

Setting mode II: the second side 122 and the first side 121 are each inclined with respect to a radial plane of the nut 100 in a direction toward an upper portion of the nut 100 such that an oblique cut 100 is formed between the first side 121 and the second side 122.

Setting mode III: the first side 121 is inclined with respect to a radial plane of the nut 100 in a direction toward an upper portion of the nut 100, and the second side 122 is inclined with respect to a radial plane of the nut 100 in a direction toward a lower portion of the nut 100 such that a desired bevel cut 100 is formed between the first side 121 and the second side 122. Also, the first side 121 needs to be at a greater angle to the radial plane of the nut 100 than the second side 122.

In general, when the first side 121 and the second side 122 are attached to each other, the second side 122 moves radially relative to the first side 121 to press the bolt 200, so as to achieve interference fit with the bolt 200 for self-locking.

It will be appreciated that, of the three arrangements described above, the second side 122 of the first arrangement is a reference plane parallel to the radial plane, which facilitates machining. Therefore, the first side edge 121 and the second side edge 122 are preferably arranged in the first arrangement manner, and the following description will also take the first arrangement manner as an example.

In this embodiment, the number of the oblique slits 100 may be one or more. For ease of understanding, the following detailed description will be made with respect to the number of the oblique slits 100 as one and two.

When the number of the oblique cuts 100 is one, as shown in fig. 6 and 7, the lower and upper parts of the nut 100 are connected by a partial region located at one side. At this time, in order to ensure that the lower part of the nut 100 can generate enough self-locking moment on the bolt 200 after swinging until the inclined notch 100 is closed, the depth X of the inclined notch 120 extending into the central threaded hole of the nut 100 is 0 < X < d, and preferably 0.2d is less than or equal to X and less than or equal to 0.8d; where d is the diameter of the threaded bore.

It will be appreciated that the sidewall portion of recess 130 of the lower end face of nut 100 is tapered surface 131, tapered surface 131 axially facing oblique cut 120, such that, after nut 100 is tightened, tapered surface 131 may flatten to conform to shim 300.

When the number of the bevel cuts 100 is two, as shown in fig. 2 to 5, the lower and upper parts of the nut 100 are connected by a partial region in the middle of the radial plane, so that the bevel cuts 100 are formed between the lower and upper parts of the nut 100 at both sides of the connection position. At this time, in order to ensure that the lower portion of the nut 100 can generate sufficient self-locking torque to the bolt 200 after swinging until the bevel cut 100 is closed, the depth X of the bevel cut 120 extending into the threaded hole is 0 < X < d/2. At the same time, the lower part of the nut 100 is prevented from being broken after swinging, and the value of X is preferably 0.d-0.3 d.

It will be appreciated that the recess 130 in the lower end face of the nut 100 is a frustoconical recess, i.e., all of the sidewalls of the recess 130 are tapered surfaces 131, such that after the nut 100 is tightened, the entire recess 130 is flattened to conform to the gasket 300.

The foregoing has outlined the basic principles, main features and advantages of the present application. It will be appreciated by persons skilled in the art that the present application is not limited to the embodiments described above, and that the embodiments and descriptions described herein are merely illustrative of the principles of the present application, and that various changes and modifications may be made therein without departing from the spirit and scope of the application, which is defined by the appended claims. The scope of protection of the present application is defined by the appended claims and equivalents thereof.

Claims (10)

1. An anti-theft self-locking fastener comprises a bolt and a nut; the method is characterized in that: the nut is of a frustum structure, a plurality of bayonets are formed in the upper side wall of the nut along the circumferential direction, and at least one inclined notch is formed in the lower side wall of the nut; when the nut and the bolt are screwed and fastened, the nut and the bolt are driven to be screwed through the unidirectional cooperation of a special tool and the bayonet until an object to be fastened is fastened; during the screwing of the nut, the lower part of the nut is pressed by a fastened object to swing towards the closing direction of the oblique incision, so that the lower part of the nut radially presses the bolt to form an interference fit.

2. The antitheft self-locking fastener of claim 1 wherein: the included angle of the oblique notch is alpha; the included angle alpha takes a value of 10 deg. -45 deg..

3. The antitheft self-locking fastener of claim 2 wherein: the lower end of the nut is provided with a groove, the side wall of the groove is provided with a conical surface, and the included angle between the conical surface and the radial plane of the nut is alpha; the lower end surface of the nut is parallel to the radial plane of the nut when the lower part of the nut swings to be tightened in the direction in which the bevel cut is closed.

4. The antitheft self-locking fastener of claim 1 wherein: the number of the oblique cuts is one.

5. The antitheft self-locking fastener of claim 4 wherein: the diameter of the threaded hole in the center of the nut is d, and the depth X of the inclined notch extending into the threaded hole is 0.1d or more and 0.9d or less.

6. The antitheft self-locking fastener of claim 1 wherein: the number of the oblique cuts is two, and the oblique cuts are symmetrically arranged on the side wall of the lower portion of the nut.

7. The antitheft self-locking fastener of claim 6 wherein: the diameter of the threaded hole in the center of the nut is d, and the depth X of the inclined notch extending into the threaded hole is 0.1d or more and 0.4d or less.

8. The antitheft self-locking fastener of any one of claims 1-7 wherein: and if the height of the nut is H, the height from the oblique notch to the lower end of the nut is 0.1H-0.3H.

9. The antitheft self-locking fastener of claim 8 wherein: the bayonet is communicated with the upper end of the nut, and the depth of the bayonet along the axial direction is 0.3H-0.6H.

10. The antitheft self-locking fastener of claim 1 wherein: the anti-theft self-locking firmware further comprises a gasket; when the nut and the bolt are fastened, the gasket is suitable for being contacted with a fastened object, and then the lower end of the nut is pressed by the gasket to swing towards the closing direction of the oblique incision.

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