Novel double-nut fastening anti-loose connecting pair

Abstract

A second screw portion of a bolt is located above a first screw portion, the diameter of the second screw portion is smaller than that of the first screw portion, a first external thread is arranged on the first screw portion, a second external thread is arranged on the second screw portion, and the thread direction of the first external thread is opposite to that of the second external thread. The first nut can be screwed at the first external thread of the first screw rod part, the second nut can be screwed at the second external thread of the second screw rod part, the lower end of the second nut is fixedly connected with an extension sleeve, and the diameter of the extension sleeve is larger than that of the first screw rod part; the lower end face of the extension sleeve can abut against the upper end face of the first nut. According to the connecting pair, the problem that existing double nuts can rotate outwards to be loosened due to vibration can be solved, and in a further scheme, the first nut and the second nut can achieve the reliable limiting and fixing anti-loosening effect through the first anti-skid ring body, the second anti-skid ring body and the cotter pin.

Description

Technical Field

[0001] The utility model belongs to the field of fasteners, and in particular relates to a novel double-nut fastening and anti-loosening connection pair. Background Art

[0002] In many mechanical devices and equipment, the nuts of their fasteners often become loose due to vibration during operation of the devices and equipment; the fastening connection form of double nuts and bolts can increase the friction between the nuts and bolts through the axial force between the nuts, thereby achieving a certain anti-loosening effect, but its anti-loosening effect is still limited, and the two nuts will also rotate synchronously and loosen outward together due to strong vibration. Summary of the invention

[0003] Based on the content in the background technology, the present application provides a novel double-nut fastening anti-loosening connection pair to solve the problem that the existing double nuts may loosen due to synchronous rotation.

[0004] A novel double-nut fastening and anti-loosening connection pair comprises a bolt, a first nut, a second nut and an extension sleeve;

[0005] The bolt comprises a first screw portion and a second screw portion, the first screw portion and the second screw portion are fixedly connected, specifically, the first screw portion and the second screw portion are integrally formed, the second screw portion is located above the first screw portion, the diameter of the second screw portion is smaller than the diameter of the first screw portion, the first screw portion is provided with a first external thread, the second screw portion is provided with a second external thread, and the thread directions of the first external thread and the second external thread are opposite;

[0006] The first nut can be screwed onto the first external thread of the first screw portion, and the second nut can be screwed onto the second external thread of the second screw portion. An extension sleeve is fixedly connected to the lower end of the second nut, and the diameter of the extension sleeve is larger than the diameter of the first screw portion. When the first nut and the second nut are both tightened, the lower end surface of the extension sleeve can contact the upper end surface of the first nut.

[0007] The use principle of the above-mentioned novel double-nut fastening anti-loosening connection pair is as follows: after the bolt is assembled, first tighten the first nut on the first screw portion of the bolt. Since the first external thread of the first screw portion and the second external thread of the second screw portion have opposite thread directions, the rotation direction of the second nut is opposite to that of the first nut. After the first nut is fixed, tighten the second nut in the opposite direction on the second screw portion of the bolt, so that the lower end face of the second nut extension sleeve contacts the upper end face of the first nut. In this way, when the first nut tends to loosen outward due to vibration, the first nut squeezes the extension sleeve and transmits the torque to the second nut through the extension sleeve. Since the rotation direction of the second nut is opposite to that of the first nut, such torque will make the second nut tighten downward more, so that the first nut cannot be loosened outward at all, avoiding the problem of the double nuts rotating outward together and loosening.

[0008] In a further solution, the upper end portion of the first nut extends outward and is integrally connected to a first anti-slip ring body, and the lower end portion of the second nut extension sleeve extends outward and is integrally connected to a second anti-slip ring body. The first anti-slip ring body can conflict with the second anti-slip ring body. When the first anti-slip ring body conflicts with the second anti-slip ring body, the friction between the second nut extension sleeve and the first nut can be increased by increasing the contact area. The larger friction force can effectively prevent the second nut from loosening outward due to vibration.

[0009] In a further solution, a plurality of limiting holes are respectively provided on the first anti-slip ring body and the second anti-slip ring body. When the first nut and the second nut are tightened, the first anti-slip ring body of the first nut contacts the second anti-slip ring body of the second nut. After at least one cotter pin passes through their relative limiting holes, the tail of the cotter pin is pulled open to limit and lock the first anti-slip ring body and the second anti-slip ring body, so that the first anti-slip ring body and the second anti-slip ring body cannot rotate relative to each other. Even if the first nut and the second nut cannot rotate relative to each other, and the first nut and the second nut have opposite rotation directions and cannot rotate synchronously, the first nut and the second nut can finally obtain a reliable limiting and fixing anti-loosening effect.

[0010] Through the above technical solution, the utility model at least includes the following beneficial effects:

[0011] The novel double-nut fastening and anti-loosening connection pair described in the present application, through the design of the second screw portion and the extension sleeve and other structures, makes the first nut and the second nut have opposite rotation directions. When the first nut tends to loosen outward due to vibration, the first nut squeezes the extension sleeve and transmits the torque to the second nut through the extension sleeve. Since the second nut and the first nut have opposite rotation directions, such torque will make the second nut tighten downward, making it impossible for the first nut to loosen outward at all, avoiding the problem of the existing double nuts rotating outward together and loosening due to vibration.

[0012] In a further solution, through the design of the structure of components such as the first anti-slip ring body, the second anti-slip ring body and the cotter pin, the first nut and the second nut can both obtain a reliable limit-fixed anti-loosening effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the overall structure of a novel double-nut fastening anti-loosening connection pair described in the implementation manner of the present application;

[0014] Figure 2 It is an exploded schematic diagram of a novel double-nut fastening anti-loosening connection pair described in an embodiment of the present application. DETAILED DESCRIPTION

[0015] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. These drawings are simplified schematic diagrams that only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the structures related to the present invention.

[0016] In the description of this application, it should be understood that if there are terms such as "upper", "lower", "left", "right", "front", "rear", etc. indicating the orientation or positional relationship, they are based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship are only used for exemplary description and cannot be understood as limiting this patent; if there are terms such as "first", "second", etc., they are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the said features. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to the specific circumstances.

[0017] In the description of the utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the utility model can be understood according to specific circumstances.

[0018] refer to Figure 1 and Figure 2 A novel double-nut fastening and anti-loosening connection pair comprises a bolt 3, a first nut 1, a second nut 2 and an extension sleeve 201;

[0019] The bolt 3 includes a first screw portion 301 and a second screw portion 302, the first screw portion 301 and the second screw portion 302 are fixedly connected, specifically, the first screw portion 301 and the second screw portion 302 are integrally formed, the second screw portion 302 is located above the first screw portion 301, the diameter of the second screw portion 302 is smaller than the diameter of the first screw portion 301, the first screw portion 301 is provided with a first external thread 303, the second screw portion 302 is provided with a second external thread 304, and the thread directions of the first external thread 303 and the second external thread 304 are opposite;

[0020] The first nut 1 can be screwed on the first external thread 303 of the first screw portion 301, and the second nut 2 can be screwed on the second external thread 304 of the second screw portion 302. The lower end of the second nut 2 is fixedly connected with an extension sleeve 201, and the diameter of the extension sleeve 201 is larger than the diameter of the first screw portion 301. When the first nut 1 and the second nut 2 are both tightened, the lower end surface of the extension sleeve 201 can contact the upper end surface of the first nut 1.

[0021] The use principle of the novel double nut fastening anti-loosening connection pair is as follows: after the bolt 3 is assembled, the first nut 1 is first tightened on the first screw part 301 of the bolt 3. Since the first external thread 303 of the first screw part 301 and the second external thread 304 of the second screw part 302 have opposite thread directions, the rotation direction of the second nut 2 is opposite to that of the first nut 1. After the first nut 1 is fixed, the second nut 2 is tightened in the opposite direction on the second screw part 302 of the bolt 3, so that the lower end surface of the extension sleeve 201 of the second nut 2 contacts the upper end surface of the first nut 1. In this way, when the first nut 1 tends to loosen outward due to vibration, the first nut 1 squeezes the extension sleeve 201 and transmits the torque to the second nut 2 through the extension sleeve 201. Since the rotation direction of the second nut 2 is opposite to that of the first nut 1, such torque will make the second nut 2 tighten downward more, so that the first nut 1 cannot be loosened outward at all, avoiding the problem that the double nuts will rotate outward together and loosen.

[0022] In a further embodiment, the upper end of the first nut 1 extends outward and is integrally connected to a first anti-slip ring body 101, and the lower end of the second nut extension sleeve 201 extends outward and is integrally connected to a second anti-slip ring body 202, and the first anti-slip ring body 101 can conflict with the second anti-slip ring body 202; when the first anti-slip ring body 101 conflicts with the second anti-slip ring body 202, the friction between the extension sleeve 201 of the second nut 2 and the first nut 1 can be increased by increasing the contact area, and the larger friction can effectively prevent the second nut 2 from being loosened outward due to vibration.

[0023] The first anti-slip ring body 101 and the second anti-slip ring body 202 are respectively provided with a plurality of limiting holes 12. When the first nut 1 and the second nut 2 are tightened, the first anti-slip ring body 101 of the first nut 1 contacts the second anti-slip ring body 202 of the second nut 2. After at least one cotter pin 4 passes through their relative limiting holes 12, the tail of the cotter pin 4 is opened to limit and lock the first anti-slip ring body 101 and the second anti-slip ring body 202, so that the first anti-slip ring body 101 and the second anti-slip ring body 202 cannot rotate relative to each other, that is, the first nut 1 and the second nut 2 cannot rotate relative to each other, and the first nut 1 and the second nut 2 cannot rotate synchronously in the same direction even though they have opposite rotation directions, so that the first nut 1 and the second nut 2 can finally obtain a reliable limiting and fixing anti-loosening effect.

[0024] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Based on the present invention and the above description, relevant personnel can make various changes and modifications without departing from the technical idea of ​​the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A new type of double nut fastening anti-loosening connection pair, characterized by: It comprises a bolt (3), a first nut (1), a second nut (2) and an extension sleeve (201); The bolt (3) comprises a first screw portion (301) and a second screw portion (302), the first screw portion (301) and the second screw portion (302) being fixedly connected, the second screw portion (302) being located above the first screw portion (301), the diameter of the second screw portion (302) being smaller than the diameter of the first screw portion (301), the first screw portion (301) being provided with a first external thread (303), the second screw portion (302) being provided with a second external thread (304), and the thread directions of the first external thread (303) and the second external thread (304) being opposite; The first nut (1) can be screwed onto the first external thread (303) of the first screw portion (301), and the second nut (2) can be screwed onto the second external thread (304) of the second screw portion (302). The lower end of the second nut (2) is fixedly connected to an extension sleeve (201), and the diameter of the extension sleeve (201) is greater than the diameter of the first screw portion (301). When the first nut (1) and the second nut (2) are both tightened, the lower end surface of the extension sleeve (201) can contact the upper end surface of the first nut (1).

2. A novel double nut fastening anti-loosening connection pair according to claim 1, characterized in that: The upper end of the first nut (1) extends outwards and is integrally connected to a first anti-slip ring body (101), and the lower end of the extension sleeve (201) extends outwards and is integrally connected to a second anti-slip ring body (202), and the first anti-slip ring body (101) can collide with the second anti-slip ring body (202).

3. A novel double nut fastening and anti-loosening connection pair according to claim 2, characterized in that: The first anti-slip ring body (101) and the second anti-slip ring body (202) are respectively provided with a plurality of limiting holes (12). When the first nut (1) and the second nut (2) are tightened, the first anti-slip ring body (101) of the first nut (1) abuts against the second anti-slip ring body (202) of the second nut (2), and after at least one cotter pin (4) passes through the corresponding limiting holes (12), the tail of the cotter pin (4) is pulled open.

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