Screw connection anti-loosening assembly used under vibration working condition

Abstract

The invention discloses a screw connection anti-loosening assembly used under a vibration working condition. The screw connection anti-loosening assembly structurally comprises an outer hexagonal screw, a locked part and an integrated anti-loosening gasket. A screw hole and an anti-rotation hole are formed in the locked part; the anti-loose gasket is made of high-elasticity alloy, and the key improvement of the anti-loose gasket is that an anti-rotation part and an elastic locking part are integrated; the anti-rotation part is matched with an anti-rotation hole in a part through a non-cylindrical limiting rib, so that the gasket is prevented from rotating; the elastic locking part is composed of a plurality of elastic pawls which are evenly distributed in the circumferential direction, the free end of the elastic locking part faces the nut, and the warping direction is opposite to the screwing direction. When the screw is tightened, part of the inverted teeth are flattened to provide continuous axial elastic pre-tightening force, and vibration is compensated to cause attenuation of the pre-tightening force; meanwhile, wedge-shaped interference is formed between the inverted teeth which are not pressed and the side edge of the nut, and mechanical locking is formed. Through the synergistic effect of elastic pre-tightening and mechanical locking, the problem that the screw is loosened in the vibration environment is effectively solved, and the anti-loosening device has the advantages of being reliable in anti-loosening and compact in structure.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of anti-loose assemblies, and particularly relates to a screw connection anti-loose assembly for a vibration working condition. BACKGROUND

[0002] The existing anti-loose technologies, such as spring washers, toothed washers, double nuts and thread locking glue, have three limitations: first, the functions are single, and most of them can only prevent one of the two loose mechanisms, i.e., pre-tightening force attenuation or rotation loosening, and lack the ability to cope with both; second, the action modes are passive and static, for example, the anti-loose ability of the spring washer will decrease with the duration of vibration, and cannot dynamically maintain effective pre-tightening force during vibration; finally, all kinds of technologies have inherent defects, such as the spring washer is easy to be crushed and fail, the toothed washer will damage the workpiece surface and is difficult to be reused, the double nut structure is heavy and the assembly process is complex, and the thread glue has problems of difficult disassembly and aging. These limitations make it difficult for the existing solutions to provide reliable and long-term anti-loose protection in severe vibration working conditions. SUMMARY

[0003] The application provides a screw connection anti-loose assembly for a vibration working condition, which effectively solves the problem of screw loosening in a vibration environment through the synergistic effect of elastic pre-tightening and mechanical locking, and has the advantages of reliable anti-loose and compact structure.

[0004] In a first aspect, the application provides a screw connection anti-loose assembly for a vibration working condition, which comprises an external hexagonal screw (1), a locked part (2) and an integrated anti-loose washer (3). The locked part (2) is provided with a screw hole (21) for the external hexagonal screw (1) to pass through and at least one anti-rotation hole (22); The integrated anti-loose washer (3) is sleeved between the nut (11) of the external hexagonal screw (1) and the contact surface of the locked part (2), and the anti-loose washer (3) is made of a high-elasticity alloy material; The anti-loose washer (3) comprises an anti-rotation part having a non-cylindrical limiting rib (32) matched with the anti-rotation hole (22) on the locked part (2) for completely restricting the rotation of the anti-loose washer (3) relative to the locked part (2) in the circumferential direction, and an elastic locking part which is a plurality of elastic inverted teeth (33) uniformly distributed in the circumferential direction around the central through hole of the anti-loose washer (3), the root of the elastic inverted tooth (33) is connected with the body of the anti-loose washer (3), the free end thereof is tilted towards the nut (11), and the tilting direction is opposite to the tightening direction of the screw; When the hexagon socket screw (1) is tightened to a specified torque, the nut (11) presses the lock washer (3) so that part of the elastic tabs (33) is pressed flat, providing a continuous axial elastic preload to compensate for the loss of preload caused by vibration; at the same time, the other part of the elastic tabs (33a) exists in a pop-up state corresponding to the specific orientation of the nut (11), and the free end of the elastic tabs (33a) forms a wedge-shaped angle with the side plane of the nut (11), constituting a mechanical lock against the counterclockwise rotation of the screw. The elastic preload and the mechanical lock work together to achieve long-term anti-loosening in a vibrating environment.

[0005] In an embodiment, the number of elastic tabs (33) is set to a number that is not a multiple of 6, and the nut (11) of the hexagon socket screw (1) is a regular hexagon. By setting N to be a multiple of 6, it is ensured that at any tightening angle of the screw, at least one of the elastic tabs (33) can form effective interference with the middle region of the side length of the nut (11), avoiding the locking failure caused by all tabs being located at the corner of the nut.

[0006] In an embodiment, the number N of elastic tabs (33) is equal to 7 or equal to 8.

[0007] In an embodiment, the cross section of the elastic tabs (33) is wedge-shaped, and the side close to the center hole of the lock washer (3) is a resisting surface, which forms an angle greater than 90 degrees with the side plane of the nut.

[0008] In an embodiment, the cross section of the limiting rib (32) is non-circular, and the limiting hole (22) is a non-circular hole matched therewith, for completely constraining the lock washer (3) in the circumferential direction.

[0009] In an embodiment, the non-circular cross section is D-shaped, rectangular or elliptical.

[0010] In an embodiment, the lock washer (3) is made of spring steel and is subjected to quenching and tempering treatment.

[0011] The application discloses a screw connection anti-loosening assembly for a vibrating working condition, which comprises an outer hexagonal screw, a locked part and an integrated anti-loosening washer. BRIEF DESCRIPTION OF DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0013] Figure 1 A structural schematic diagram of the screw connection anti-loosening assembly for the vibrating working condition provided in an embodiment of the present application is shown in the figure. Figure 2a A three-dimensional structural schematic diagram of the integrated anti-loosening washer in the embodiment is shown in the figure. Figure 1 A three-dimensional structural schematic diagram of the integrated anti-loosening washer in the embodiment is shown in the figure. Figure 2b A three-dimensional structural schematic diagram of the integrated anti-loosening washer in the embodiment is shown in the figure. Figure 1 A three-dimensional structural schematic diagram of the integrated anti-loosening washer in the embodiment is shown in the figure. DETAILED DESCRIPTION

[0014] In the following description, specific details are set forth in order to provide a thorough understanding of the embodiments of the present application. However, persons skilled in the art should understand that the present application can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits and methods are omitted so as not to obscure the description of the present application with unnecessary details.

[0015] It should be understood that when used in the specification and the appended claims of the present application, the term "comprising" indicates the presence of the described features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0016] It should also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items, and that the term "at least one of' as used herein refers to at least one or more items in the associated list and that the term "permutations" as used herein refers to any and all possible combinations of one or more of the associated listed items.

[0017] As used in the description of the application and the appended claims, the term "if' can be interpreted to mean "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrase "if it is determined" or "if [a described condition or event] is detected" can be interpreted to mean "upon determining" or "in response to determining" or "upon detecting [the described condition or event]" or "in response to detecting [the described condition or event]," depending on the context.

[0018] In addition, the terms "first", "second", "third", etc. as used in the description of the application and the appended claims are merely used for distinguishing between similar underlying features and do not connote or imply any relative importance.

[0019] Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the application. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" or "in some embodiments" or "in other embodiments" or "in still other embodiments" in various places throughout this specification are not necessarily all referring to the same embodiment, unless otherwise specifically stated. The term "comprising," "including," "containing," and variations thereof as used herein are meant to encompass the presence of stated features, structures, or characteristics, but do not preclude the presence or addition of one or more other features, structures, or characteristics. The term "comprising" means "including, containing, or comprising, but not limited to."

[0020] Reference will now be made, by way of example only, to the drawings in which Figure 1 and Figure 2, Figure 1 Figure 1 is a structural schematic diagram of a screw connection anti-loosening assembly in a vibration working condition according to an embodiment of the application. Figure 2 is a perspective structural schematic diagram of an integrated anti-loosening washer shown in Figure 1. Figure 1 Figure 2 is a perspective structural schematic diagram of an integrated anti-loosening washer shown in Figure 1.

[0021] As can be seen from Figure 1 It can be seen that the anti-loosening assembly (10) is mainly composed of three parts, namely, an external hexagonal screw (1), a locked part (2), and an integrated anti-loosening washer (3). The locked part (2) is provided with a screw hole (21) through which the external hexagonal screw (1) passes and at least one anti-rotation hole (22).

[0022] In the embodiment, the anti-rotation hole (22) is preferably located beside the screw hole (21). The integrated anti-loosening washer (3) is sleeved between the nut (11) of the outer hexagonal screw (1) and the contact surface of the locked part (2). The anti-loosening washer (3) is made of a high-elastic alloy material, which ensures good fatigue strength and elastic recovery capacity.

[0023] As shown in FIG. 2, the anti-loosening washer (3) includes an anti-rotation part having a non-cylindrical limiting rib (31) matched with the anti-rotation hole (22) on the locked part (2), which is used to completely constrain the rotation of the anti-loosening washer (3) relative to the locked part (2) in the circumferential direction. In the embodiment, the cross section of the limiting rib (31) can be D-shaped, rectangular, or elliptical, etc. During assembly, the limiting rib (31) is accurately inserted into the anti-rotation hole (22) on the locked part (2) which is completely matched with the shape. The non-circular matching relationship realizes the complete constraint of the anti-loosening washer (3) in the circumferential direction, which ensures that the washer will not rotate relative to the locked part (2) under any circumstances, and establishes a stable foundation for the subsequent locking function.

[0024] An elastic locking part is a plurality of elastic inverted teeth (33) uniformly distributed in the circumferential direction around the central through hole of the anti-loosening washer (3). As shown in FIG. 2, the elastic inverted teeth (33) are formed by stamping or other plastic processing, the roots of which are connected with the body of the anti-loosening washer (3), and the free ends thereof are tilted towards the nut (11) in the opposite direction of the tightening direction of the screw, i.e. in the counterclockwise direction. When the outer hexagonal screw (1) is tightened to a specified torque, the nut (11) will press the underlying anti-loosening washer (3), so that part of the elastic inverted teeth (33) is elastically flattened, continuously providing an axial elastic pre-tightening force to compensate for the loss of pre-tightening force caused by vibration; at the same time, another part of the elastic inverted teeth (33a) exists in a tilted state corresponding to the specific orientation of the nut (11), and the tilted free end forms a wedge-shaped angle with the side plane of the nut (11), constituting a mechanical locking against the counterclockwise rotation of the screw. The elastic pre-tightening force and the mechanical locking work together to achieve long-term anti-loosening in a vibrating environment.

[0025] Specifically, since the lower surface of the nut (11) is a flat surface, and the upper surface of the anti-loosening washer (3) is an uneven surface with tilted inverted teeth (33), during tightening, part of the elastic inverted teeth (33) will be directly flattened by the nut (11) (as shown in FIG. 3), and the other part of the elastic inverted teeth (33a) will be tilted in the opposite direction of the tightening direction of the screw, i.e. in the counterclockwise direction. Figure 2bThe flattened teeth (33) act like compressed micro-springs, generating a constant upward axial elastic rebound force acting on the nut (11). This force is directly translated into additional pre-tightening force of the screw joint, dynamically compensating the pre-tightening force decay caused by vibration, effectively suppressing "pre-tightening relaxation".

[0026] Since the elastic teeth (33) are evenly distributed in the circumference, and the nut (11) is a regular hexagon, at any final tightening angle of the screw, there will always be another part of the elastic teeth (33) that cannot be pressed flat by the flat surface of the nut (11), and remains in the raised state (as shown in Figure 2b The raised teeth (33) have their raised free ends located right on the rotation path of the nut (11) and form a sharp wedge angle with the flat surface of the nut (11). Figure 1

[0027] When the device vibrates and tries to drive the screw (1) to rotate counterclockwise, the flat surface of the nut (11) will approach and contact the free end of the raised tooth (33). Since the root of the tooth (33) is fixed (by the anti-rotation part), and the side close to the central through-hole (31) is designed as a resistance surface (the angle between this surface and the flat surface of the nut is greater than 90 degrees), the counterclockwise torque will be converted into a force that presses the tooth (33) more tightly against the surface of the locked part (2), generating a large friction force and mechanical interference, thus firmly locking the rotation of the screw like a wedge. At this time, the constant axial pre-tightening force provided by the flattened teeth (33) ensures the tight contact between the connecting surfaces, providing the necessary normal pressure for mechanical locking; and the reliable mechanical locking ensures that the axial pre-tightening force will not be quickly lost due to the slight rotation of the screw. These two mechanisms complement each other and together form a highly reliable and long-lasting anti-loose system in a vibrating environment.

[0028] In an embodiment, the number of elastic teeth (33) is set to be a divisor of 6, and the nut (11) of the external hexagonal screw (1) is a regular hexagon. By setting N to be a divisor of 6, it is ensured that at any tightening angle of the screw, at least one of the elastic teeth (33) can form effective interference with the middle region of the side length of the nut (11), avoiding the locking failure caused by all teeth being located at the corner of the nut.

[0029] In an embodiment, the number N of elastic teeth (33) is equal to 7 or equal to 8.

[0030] ​Specifically, to ensure the reliability of the locking, the number N of the elastic inverted teeth 33 is set to be not equal to the divisor of 6 (the number of the sides of the outer hexagonal nut), for example, N=7 or N=8. The purpose of this design is to ensure that at least one elastic inverted tooth 33a can be located below the middle region of a side length 11a of the nut 11 to form effective wedge interference, by virtue of the mathematical co-prime relationship, no matter at which angle the screw 1 stops after being tightened. If N is the divisor of 6 (for example, 3 or 6), it is possible that all the inverted teeth are just aligned with the six corners of the nut 11, resulting in the weakening or even failure of the locking function.

[0031] In an embodiment, the anti-loose washer (3) is made of spring steel and is subjected to quenching and tempering treatment. Specifically, the anti-loose washer (3) is preferably made of 60Si2MnA or similar spring steel. During manufacturing, the quenching and tempering heat treatment process is required. Quenching can improve the strength and hardness of the material, while tempering can eliminate internal stress and impart the desired elasticity to the material. By precisely controlling the heat treatment process parameters, the surface hardness of the washer can reach HRC 42-48, so as to ensure that the elastic inverted teeth 33 have sufficient strength and wear resistance, and also achieve excellent elastic performance.

[0032] The application discloses a screw connection anti-loose assembly for a vibration working condition, which comprises an outer hexagonal screw, a locked part and an integrated anti-loose washer. The locked part is provided with a screw hole and an anti-rotation hole. The anti-loose washer is made of high-elasticity alloy, and the key improvement lies in that the anti-rotation part and the elastic locking part are integrated. The anti-rotation part is matched with the anti-rotation hole on the part through a non-cylindrical limiting rib, so that the rotation of the washer is prevented. The elastic locking part is composed of a plurality of elastic inverted teeth which are uniformly distributed in the circumferential direction, the free ends of the elastic inverted teeth are directed towards the nut and are tilted towards the opposite direction of the tightening direction. When the screw is tightened, part of the inverted teeth are flattened to provide a continuous axial elastic pre-tightening force, so as to compensate for the pre-tightening force attenuation caused by vibration. Meanwhile, the inverted teeth which are not subjected to pressure form wedge interference with the side of the nut, thereby constituting mechanical locking. The anti-loose assembly effectively solves the problem of screw loosening in the vibration environment through the synergistic effect of elastic pre-tightening and mechanical locking, and has the advantages of reliable anti-loose and compact structure.

[0033] In addition, the anti-loose assembly (10) in the first aspect is applied to a high-voltage switch device in the embodiment. The high-voltage switch device is a key control and protection device in a power system, and the reliability and service life of the operation of the high-voltage switch device are directly related to the safe and stable operation of the power grid.

[0034] The high-voltage switchgear provided in this application embodiment, exemplarily, includes a permanent magnet mechanism, an iron core, and an insulating tie rod. The iron core and the insulating tie rod are connected by a screw connection structure to achieve power transmission. This connection point (i.e., the connecting flange of the iron core and the insulating tie rod) is a key mechanical interface in the entire operation transmission chain. The screw connection structure is the anti-loosening component as described in the first aspect above. When the high-voltage switch performs an opening or closing operation, the permanent magnet mechanism releases enormous energy, driving the iron core to produce extremely fast linear motion (usually completed within milliseconds). This instantaneous start-stop and reversing process will induce strong, transient mechanical vibrations and impacts in the iron core, the insulating tie rod, and their connecting structure. This vibration is not a gentle, continuous vibration, but an impact vibration with high acceleration and high frequency characteristics. Under this dynamic environment, traditional screw anti-loosening solutions are prone to failure, specifically manifested in the rapid "crushing" of the spring washer and loss of elasticity. Ordinary flat washers or double-nut structures cannot resist high-frequency micro-rotation, and the screw connection will quickly experience preload decay, leading to fretting wear on the mating surface, further aggravating loosening. If this critical connection point becomes loose, it can lead to inaccurate transmission, drift in operating time characteristics, abnormal impacts and noise, and in severe cases, it may cause equipment to malfunction or fail to operate, resulting in huge safety hazards and economic losses.

[0035] To address this specific technical problem, this embodiment explicitly states that the screw connection structure between the iron core and the insulating tie rod employs an anti-loosening component. When the permanent magnet mechanism generates a severe impact, the continuous axial preload provided by the flattened elastic teeth on the anti-loosening washer acts like a set of "buffer springs," dynamically absorbing and compensating for the instantaneous fluctuations in preload caused by the impact, always keeping the connection surface in a compressed state, effectively suppressing fretting wear. At the instant the iron core's movement suddenly stops, the enormous inertial force attempts to cause the screw connection to rotate in the opposite direction. At this moment, the mechanical locking mechanism formed by the spring-loaded elastic teeth and the side of the nut immediately comes into play. This locking action, based on a rigid constraint of physical interference, can respond instantly and effectively resist this inertial rotation tendency, with reliability and immediacy far exceeding traditional solutions relying on friction.

[0036] By applying anti-loosening components to the core-insulation tie rod connection of high-voltage switchgear, the accuracy and consistency of power transmission are ensured. This avoids characteristic drift caused by loose connections and effectively suppresses fretting wear on the connection surfaces, reducing maintenance needs and downtime. It fundamentally eliminates the potential for major operational accidents caused by loose critical mechanical connections.

[0037] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A screw connection anti-loosening component for use under vibration conditions, characterized in that, include: External hexagonal screw (1), locked part (2) and integrated anti-loosening washer (3); The locked part (2) has a screw hole (21) for the external hexagonal screw (1) to pass through and at least one anti-rotation hole (22). The integrated anti-loosening washer (3) is sleeved between the nut (11) of the external hexagonal screw (1) and the contact surface of the locked part (2), and the anti-loosening washer (3) is made of a high elastic alloy material; The anti-loosening washer (3) includes: an anti-rotation part having a non-cylindrical limiting rib (32) that cooperates with the anti-rotation hole (22) on the locked part (2) for completely restraining the rotation of the anti-loosening washer (3) relative to the locked part (2) in the circumferential direction; and an elastic locking part consisting of a plurality of elastic back teeth (33) evenly distributed in the circumferential direction around the central through hole on the anti-loosening washer (3), the root of the elastic back teeth (33) being connected to the body of the anti-loosening washer (3), and the free end of the teeth tilting upward toward the nut (11) in the opposite direction to the tightening direction of the screw. When the external hexagonal screw (1) is tightened to the specified torque, the nut (11) presses against the anti-loosening washer (3), causing part of the elastic back teeth (33) to be elastically flattened, continuously providing axial elastic preload to compensate for the preload loss caused by vibration; at the same time, another part of the elastic back teeth (33a) are in a spring-up state due to their specific orientation corresponding to the nut (11), and their raised free end forms a wedge angle with the side plane of the nut (11), constituting a mechanical lock for the screw to rotate counterclockwise; The elastic preload and the mechanical locking work together to achieve long-term anti-loosening under vibration conditions.

2. The anti-loosening component according to claim 1, characterized in that, The number of the elastic back teeth (33) is set to a factor not equal to 6, and the nut (11) of the external hexagonal screw (1) is a regular hexagon.

3. The anti-loosening component according to claim 2, characterized in that, The number N of the elastic reverse teeth (33) is equal to 7 or equal to 8.

4. The anti-loosening component according to claim 1, characterized in that, The cross-section of the elastic reverse tooth (33) is wedge-shaped, and the side of it near the central through hole of the anti-loosening washer (3) is a resistance surface. The angle between the resistance surface and the side plane of the nut is greater than 90 degrees.

5. The anti-loosening component according to claim 1, characterized in that, The cross-section of the limiting rib (32) is non-circular, and the limiting hole (22) is a matching non-circular hole, used to completely constrain the anti-loosening gasket (3) in the circumferential direction.

6. The anti-loosening component according to claim 5, characterized in that, The non-circular cross-section is D-shaped, rectangular, or elliptical.

7. The anti-loosening component according to claim 1, characterized in that, The anti-loosening gasket (3) is made of spring steel and has been quenched and tempered.

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