Retaining screw

Abstract

The utility model discloses a retaining screw which comprises a nut and a screw rod section connected to the inner end face of the nut. A plurality of ribs distributed in the circumferential direction of threads of the screw rod section are formed on the inner end face of the nut, the ribs extend and are folded from the outer circumference to the circle center in the radial direction of the nut, a retaining washer is arranged on the inner end face of the nut, a plurality of retaining grooves are formed in the end, opposite to the inner end face of the nut, of the retaining washer, and each rib can be correspondingly clamped into the corresponding retaining groove. The nut and the retaining washer are relatively fixed, the retaining screw is prevented from loosening and reversely rotating and falling off, a retaining matching structure does not need to be arranged at the joint, the structure is simple, and the installation efficiency is high. The other end of the retaining washer abuts against the head end of the screw rod section, the radial length of the retaining washer is gradually reduced, the retaining washer can be in interference fit with a hole in the connecting position, friction force of threaded connection is increased, the contact area between the retaining washer and the connecting position is increased, the inner end face of the nut can be prevented from directly applying too large pressure to the surface of the connecting position, and damage to the connecting position is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of screws, in particular to a backstop screw. Background Art

[0002] Screws, also known as screws, include threaded fasteners consisting of a nut as a head structure and a screw segment connected to the nut. They are a common fastener and are widely used in many industries such as machinery, electricity, transportation, and aerospace.

[0003] During the use of screws, the friction between the threaded connections is reduced due to various reasons such as vibration or mechanical movement or thermal contraction and creep of the material, which often causes the threaded connection to loosen, thereby causing the thread to rotate in the opposite direction or even fall off. Many of the commonly used backstop screws on the market are pre-processed with a backstop matching structure that cooperates with the screw stop structure on the connection point such as the surface of the equipment into which the thread is installed. For example, a convex point is processed on the screw and a groove is opened on the connection point.

[0004] However, the structure of the connection needs to be pre-processed, which limits the range of connections where the screws are applicable. Some connections are not necessarily suitable for setting a backstop fit structure. Once the corresponding backstop fit structure is set, the structure of the connection will undergo irreversible changes. In addition, the setting of the backstop fit structure is cumbersome, which affects the installation efficiency, increases the installation cost, and has high quality requirements.

[0005] Therefore, it is necessary to propose a new anti-retraction screw improvement plan to solve the above problems. Utility Model Content

[0006] In view of this, the purpose of the present invention is to provide a stop screw to solve the above problem.

[0007] In order to achieve the above-mentioned purpose, the utility model adopts the following technical solutions:

[0008] The utility model provides a back-stop screw, which comprises a nut and a screw rod section connected to the inner end surface of the nut.

[0009] Among them, a plurality of ribs are formed on the inner end face of the nut and are arranged circumferentially around the thread of the screw segment. The ribs extend and converge from the outer circumference to the center of the circle along the radial direction of the nut. A backstop washer is provided on the inner end face of the nut. A plurality of backstop grooves are formed at one end of the backstop washer facing the inner end face of the nut and are arranged at intervals to form an annular backstop groove. Each rib can be correspondingly snapped into the backstop groove to relatively fix the nut and the backstop washer. The other end of the backstop washer abuts against the head end of the screw segment. Along the axial direction of the screw segment toward the head end of the screw segment, the radial length of the backstop washer gradually decreases.

[0010] Preferably, the anti-retraction washer is provided with 12 anti-retraction grooves circumferentially surrounding the thread of the screw segment.

[0011] Preferably, six ribs are formed on the inner end surface of the nut, and adjacent ribs are arranged at equal intervals.

[0012] Preferably, the angle between the side surface of the rib and the inner end surface of the nut is a right angle.

[0013] Preferably, the backstop washer is a stainless steel washer, and the surfaces of the backstop washer and the nut are formed with a zinc-chromium coating.

[0014] Preferably, a main mold tail is formed on the end of the screw segment away from the nut.

[0015] Preferably, a plum-shaped countersunk groove is formed on the outer end surface of the nut.

[0016] Preferably, the radial length of the nut is set to 13.8-14.0 mm, the inner diameter length of the backstop washer is set to 5.35-5.45 mm, the outer diameter length of the screw segment is set to 5.82-5.96 mm, the radial length of the main mold tail is set to 4.2-4.4 mm, and the thickness of the main mold tail is set to 2.0-2.5 mm.

[0017] The technical effects achieved by the technical solution of the utility model include:

[0018] The above-mentioned back-retraction screw forms circumferentially arranged ribs on the inner end surface of the nut. By passing the back-retraction washer through the inner end surface of the nut, the ribs are clamped into the back-retraction groove of the back-retraction washer, so that the nut and the back-retraction washer are relatively fixed, limiting the rotation of the back-retraction screw, preventing the back-retraction screw from loosening and reversely falling off, and it is unnecessary to set a back-retraction matching structure at the connection. The structure is simple, can be adapted to more connection structures, has high installation efficiency, and has low installation cost.

[0019] The radial length of the stop washer is gradually reduced, and it can be interference-fitted with the corresponding connection hole of the connection, which can further play the role of fastening the nut and the connection and nut, and increase the friction of the threaded connection. In addition, the stop washer increases the contact area between the connection and the connection, which can prevent the inner end face of the nut from directly applying excessive pressure to the surface of the connection, thereby reducing the possibility of damage to the connection.

[0020] The retaining screw can be used as a grounding screw, and the retaining groove of the retaining washer is used to clamp the installed power cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the structure of the stop screw provided by the embodiment of the utility model;

[0022] Figure 2 It is a schematic diagram of the docking state between the stop groove and the rib in the stop screw;

[0023] Figure 3 It is a schematic structural diagram of the side where the outer end surface of the nut in the back-stop screw is located.

[0024] The reference numerals in the above drawings are:

[0025] Nut 1, inner end face 1a of nut, outer end face 1b of nut, plum blossom countersunk groove 10, rib 11, screw segment 2, main mold tail 21, anti-retraction washer 3, anti-retraction groove 30. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the utility model clearer, the specific embodiments of the utility model are described in detail below in conjunction with the accompanying drawings. Examples of these preferred embodiments are illustrated in the accompanying drawings. The embodiments of the utility model shown in the accompanying drawings and described according to the accompanying drawings are merely exemplary, and the utility model is not limited to these embodiments.

[0027] It should also be noted that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the solution according to the present invention are shown in the accompanying drawings, while other details that are not very relevant are omitted.

[0028] Combination Figures 1 to 3 As shown, an embodiment of the utility model provides a back-stop screw, which includes a nut 1 and a screw segment 2 connected to the inner end surface 1 a of the nut 1 .

[0029] Among them, a plurality of ribs 11 are formed on the inner end face 1a of the nut 1 and are arranged circumferentially around the threads of the screw segment 2. The ribs 11 extend and converge from the outer circumference to the center of the circle along the radial direction of the nut 1 to form a multi-blade structure. A backstop washer 3 is provided on the inner end face 1a of the nut 1. The backstop washer 3 passes through the screw segment 2 and is inserted and covers the inner end face 1a of the nut 1. The backstop washer 3 is formed with a plurality of backstop grooves 30 arranged at intervals to form an annular shape at one end facing the inner end face 1a of the nut 1. Each rib 11 can be correspondingly snapped into the backstop groove to fix the nut 1 and the backstop washer 3 relatively. The other end of the backstop washer 3 abuts against the head end of the screw segment 2. Along the axial direction of the screw segment 2 toward the head end of the screw segment 2, the radial length of the backstop washer 3 gradually decreases to form a truncated cone.

[0030] The above-mentioned backstop screw is installed on the connection point such as the surface of the equipment. After the screw segment 2 is fixed to the connection point by threaded connection, the backstop washer 3 is clamped between the nut 1 and the connection point. The rib 11 on each nut 1 is clamped with a corresponding backstop groove, so that the nut 1 and the backstop washer 3 are relatively fixed, and the rotation of the backstop screw is restricted to prevent the backstop screw from loosening and reverse falling off; the backstop washer 3 can be interference fit with the corresponding connection hole of the connection point, which can further play the role of tightening the nut and the connection point and the nut, and increase the friction of the threaded connection; and the backstop washer 33 can increase the contact area between the connection points such as the surface of the assembled machine and equipment, and can avoid the inner end face 1a of the nut 2 directly applying excessive pressure to the surface of the connection point, play a role of shock absorption and buffering, and reduce the possibility of damage to the connection point; when the backstop screw is used as a grounding screw, etc., the backstop groove of the backstop washer can be used to clamp and grasp the installed power cable.

[0031] The anti-retreat grooves 30 on the anti-retreat washer 3 are arranged in a regular and symmetrical distribution, and can be used as standard parts rather than special shapes, which can facilitate the production of the anti-retreat washer 3, improve work efficiency, reduce production costs, and also appear beautiful and neat. Of course, technicians in this field can reasonably modify it according to their own needs, change the distribution and shape of the anti-retreat grooves 30 of the anti-retreat washer 3. For example, in this embodiment, the anti-retreat washer 3 is formed with 12 anti-retreat grooves 30 around the thread circumference of the screw segment 2, and each anti-retreat groove 30 is distributed at equal intervals.

[0032] Exemplarily, six ribs 11 are formed on the inner end surface 1 a of the nut 1 , and in order to cooperate with the distribution of the stop grooves 30 to play a stopping role with uniform force, the adjacent ribs 11 are arranged with equal spacing.

[0033] In this embodiment, the angle between the side surface of the rib 11 and the inner end surface 1 a of the nut 1 is a right angle, that is, the rib 11 and the inner end surface 1 a of the nut 1 are perpendicular to each other.

[0034] The anti-retraction washer 3 is a stainless steel washer. In this example, the nut 1, the screw segment 2 and the anti-retraction washer 3 are preferably made of SUS430 stainless steel. The surfaces of the anti-retraction washer 3 and the nut 1 are formed with a zinc-chromium coating, that is, they are surface treated with Dacromet. During the production, the screw segment 2 is formed by heading, inserting the anti-retraction washer 3, and rolling the threads. Then, the entire anti-retraction screw is subjected to the above-mentioned Dacromet, shot blasting, sandblasting, and salt spray treatment for 360 hours to ensure that the anti-retraction screw is not easy to rust.

[0035] Specifically, a main mold tail 21 is formed on the end of the screw segment 2 away from the nut 1. The main mold tail 21 of the screw segment 2 can be used to adjust the axial length of the screw segment 2 according to the connection, and is flush with the specific structure in conjunction with the stop washer 3. The main mold tail 21 is convenient for passing through the through hole of the connection for fixed connection.

[0036] like Figure 3 The diagram shown corresponds to the front view from the side where the outer end face of the nut in the stop screw is located. Furthermore, a plum blossom countersunk groove 10 is formed on the outer end face 1b of the nut 1, and the plum blossom countersunk groove 10 is convenient for assembly.

[0037] Combination Figure 1 and Figure 2 As shown, the preferred specifications and dimensions of the upper part of the above-mentioned stop screw are as follows:

[0038] The radial length D1 of the nut 1 is set to 13.8-14.0 mm, the inner diameter length D2 of the backstop washer 3 is set to 5.35-5.45 mm, the outer diameter length D3 of the screw segment 2 is set to 5.82-5.96 mm, the radial length D4 of the main mold tail 21 is set to 4.2-4.4 mm, and the thickness H1 of the main mold tail 21 is set to 2.0-2.5 mm.

[0039] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0040] The above is only a specific implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A stop screw, characterized in that: It comprises a nut (1) and a screw segment (2) connected to the inner end surface (1a) of the nut (1). The inner end surface (1a) of the nut (1) is provided with a plurality of ribs (11) which are arranged circumferentially around the threads of the screw segment (2); the ribs (11) extend and converge from the outer circumference to the center of the circle along the radial direction of the nut (1); a backstop washer (3) is provided on the inner end surface (1a) of the nut (1); a plurality of backstop grooves (30) which are arranged in an annular shape and are spaced apart from each other are formed on the end of the backstop washer (3) facing the inner end surface (1a) of the nut (1); each rib (11) can be correspondingly snapped into the backstop groove so that the nut (1) and the backstop washer (3) are relatively fixed; the other end of the backstop washer (3) abuts against the head end of the screw segment (2); and the radial length of the backstop washer (3) gradually decreases along the axial direction of the screw segment (2) toward the head end of the screw segment (2).

2. The stop screw according to claim 1, characterized in that: The anti-retraction washer (3) is provided with 12 anti-retraction grooves (30) surrounding the thread circumference of the screw segment (2).

3. The stop screw according to claim 2, characterized in that: Six ribs (11) are formed on the inner end surface (1a) of the nut (1), and adjacent ribs (11) are arranged at equal intervals.

4. The stop screw according to claim 1, characterized in that: The angle between the side surface of the rib (11) and the inner end surface (1a) of the nut (1) is a right angle.

5. The stop screw according to claim 1, characterized in that: The anti-retraction washer (3) is a stainless steel washer, and zinc-chromium coatings are formed on the surfaces of the anti-retraction washer (3) and the nut (1).

6. The stop screw according to claim 1, characterized in that: A main mold tail (21) is formed on the end of the screw segment (2) away from the nut (1).

7. The stop screw according to claim 1, characterized in that: A plum blossom countersunk groove (10) is formed on the outer end surface (1b) of the nut (1).

8. The stop screw according to claim 6, characterized in that: The radial length of the nut (1) is set to 13.8-14.0 mm, the inner diameter length of the backstop washer (3) is set to 5.35-5.45 mm, the outer diameter length of the screw segment (2) is set to 5.82-5.96 mm, the radial length of the main mold tail (21) is set to 4.2-4.4 mm, and the thickness of the main mold tail (21) is set to 2.0-2.5 mm.

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