CN208123221U - It is a kind of to determine torque anti-loosening locking bolt group - Google Patents

Abstract

The utility model relates to a fixed-torque anti-loosening locking bolt group, which includes bolts, fastening nuts and locking nuts. thread, the locking thread is arranged on the outside of the fastening thread, and the upper end surface of the fastening nut matched with the fastening thread is provided with a waist-shaped annular boss that is sunken toward the center. The lower end surface of the lower end is provided with a cylindrical boss matching the waist-shaped annular boss, the height of the waist-shaped annular boss and the cylindrical boss is equal to the pitch of the locking thread, and the waist-shaped annular boss The platform and the cylindrical boss are interference fit, and the tolerance of the interference fit matches the locking torque. During the screwing process of the utility model, the fixed-torque interlocking can be realized by using the cylindrical boss of the lock nut to embed into the waist-shaped boss of the fastening nut. In addition, the outer structure and size of the fastening nut and the lock nut are exactly the same, so that it is convenient to use a unified tool.

Description

A fixed torque anti-loosening locking bolt group

technical field

The utility model relates to a fixed-torque anti-loosening locking bolt group.

Background technique

Threaded fasteners, including screws, bolts and studs, are commonly used standard parts in various industries. Usually, threaded fasteners adopt single-thread ordinary threads, which generally will not loosen under a certain pre-tightening force, but when they are subjected to vibration, impact and variable loads, the frictional resistance between thread pairs will decrease instantaneously. If this phenomenon is repeated many times, it will cause the threaded fasteners to loosen, which will affect the normal operation of the machine if it is light, and will endanger the safety of the person and the machine if it is serious. Therefore, in order to ensure the safety and reliability of the connection, Effective anti-loosening measures must be taken.

There are various thread anti-loosening measures, among which double nut anti-loosening is a commonly used thread anti-loosening method. This anti-loosening method adopts the principle of two-way thread-to-top interlocking. When the trend of the fastening nut and the lock nut are opposite, the lock nut is tightened when the fastening nut is loosened, so as to prevent the fastening nut from loosening. However, this anti-loosening structure is unstable, and the anti-loosening effect of the thread cannot be guaranteed. In addition, when the thread is locked, a specific tool (torque wrench) is often required to determine whether the torque meets the requirements. The operator must lock the various bolts. The tightening torque is very clear, which is inconvenient for the use of general tools and the work of installers.

Utility model content

The purpose of the utility model is to provide a fixed-torque anti-loosening locking bolt group with good anti-loosening effect and controllable torque.

The technical scheme of the utility model is a fixed-torque anti-loosening locking bolt group, which includes bolts, fastening nuts, and locking nuts. thread and locking thread, the locking thread is arranged on the outside of the fastening thread, and the upper end surface of the fastening nut matched with the fastening thread is provided with a waist-shaped annular boss that is sunken toward the center. The lower end surface of the lock nut is provided with a cylindrical boss matching the waist-shaped annular boss, and the height of the waist-shaped annular boss and the cylindrical boss is equal to the pitch of the locking thread. The ring-shaped boss and the cylindrical boss are interference fit, and the tolerance of the interference fit matches the locking torque.

Preferably, for ease of operation, the pitch of the fastening thread is greater than that of the locking thread.

Preferably, the outer structures and dimensions of the fastening nut and the locking nut are exactly the same.

When locking, first screw the fastening nut to the fastening thread section of the bolt, and then screw the lock nut to the locking thread section of the bolt. During the screwing process, the cylindrical boss of the latter will be embedded in the waist-shaped boss of the former to achieve constant torque interlocking. In addition, the outer structure and size of the fastening nut and the lock nut are exactly the same, which facilitates the use of a unified tool.

The beneficial technical effect of the utility model is that the fastening nut and the lock nut with opposite rotation directions are used to form an interlock, so that the nut cannot move up and down. During the screwing process, the cylindrical boss of the lock nut is embedded in the waist of the fastening nut. In the type boss, the constant torque interlock can be realized. In addition, the outer structure and size of the fastening nut and the lock nut are exactly the same, which facilitates the use of a unified tool. The utility model has the advantages of simple structure, good anti-loosening effect, no specific torque tool, convenient installation and good versatility.

Description of drawings

Fig. 1 is the structural representation of the utility model embodiment;

Fig. 2 is the schematic diagram of the structure of the locking nut of the embodiment of the utility model;

Fig. 3 is a schematic diagram of the structure of the fastening nut of the embodiment of the utility model.

Detailed ways

The utility model will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

Referring to the accompanying drawings, a set of fixed-torque anti-loosening locking bolts includes a bolt 1, a fastening nut 2, and a locking nut 3. The tail of the bolt 1 is provided with two sections of stepped and oppositely-rotated fastening bolts. thread 2 and locking thread 3, the locking thread 3 is arranged on the outer side of the fastening thread, and the upper end surface of the fastening nut 2 matched with the fastening thread is provided with a waist-shaped annular protrusion concave toward the center Platform 7, a cylindrical boss 6 that matches the waist-shaped annular boss 7 is provided on the lower end surface of the lock nut 3, and the height of the waist-shaped annular boss 7 and the cylindrical boss 6 is equal to The pitch of the locking thread, the waist-shaped annular boss 7 and the cylindrical boss 6 are an interference fit, and the tolerance of the interference fit matches the locking torque. In order to facilitate operation, the pitch of the fastening thread greater than the pitch of the locking thread, the external structure and size of the fastening nut 2 and the locking nut 3 are exactly the same, when locking, first screw the fastening nut 2 to the fastening thread section of the bolt 1, and then tighten The nut 3 is screwed to the locking thread section of the bolt 1 . During the screwing process, the cylindrical boss 6 of the latter will be embedded in the annular boss 7 of the former to realize constant torque interlocking. In addition, the outer structures and dimensions of the fastening nut 2 and the locking nut 3 are exactly the same, which facilitates the use of uniform tools.

With reference to accompanying drawings 1 , 2 and 3 , the working principle of the fixed torque anti-loosening locking bolt group of the present invention will be described. The fixed torque anti-loosening locking bolt group is composed of a double-threaded bolt 1, a fastening nut 2, a locking nut 3, a fastened part 4 and a fastening part 5. The tail of the double-threaded bolt 1 is stepped, including two sections of external threads with opposite directions and different sizes. The double-threaded bolt 1 first passes through the fastened part 4 and the fastening part 5, and then fastened with the fastening nut 2 , when the fastening nut 2 is installed, it must be ensured that the annular boss 7 of the concave structure faces the tail of the bolt, and it is screwed into the large thread section of the double-threaded bolt 1; finally, it is fastened with the lock nut 3 and screwed into the small thread section of the double-threaded bolt 1, Note that the circular boss 6 on the end face of the lock nut 3 faces the lock nut 2. After reaching the specified torque, it will squeeze into the groove of the ring boss 7 of the lock nut 2, so that the lock nut 2 and the lock nut 3 are interlocked and become one; at the same time, because the two sections of the double-threaded bolt 1 have opposite threads, the nut group composed of the fastening nut 2 and the lock nut 3 is interlocked on the double-threaded bolt 1 and cannot move up and down. The purpose of anti-loosening of fasteners. When the fastened parts need to be disassembled, the fastening nut 2 and the lock nut 3 must reach the specified torque before they can be disassembled. After disassembly, the two nuts become independent entities and can be easily disassembled.

The diameter of the near-end thread of the bolt head of the double-threaded bolt 1 in the utility model is greater than the diameter of the distal thread, and the diameter of the internal thread of the fastening nut 2 is greater than the diameter of the internal thread of the lock nut 3 . The upper end surface of fastening nut 2 has the annular boss 7 of concave structure, and the lower end surface of lock nut 3 has circular boss 6, and the height of boss is all equal to the pitch of small thread section of double-threaded bolt 1, and the screw When fitting, the circular boss 6 of the latter will be embedded in the groove of the former annular boss 7 to realize interlocking; in order to make the bosses on the fastening nut 2 and the locking nut 3 can cooperate and lock, it must be guaranteed The amount of outcropping of the thread after the fastening nut 2 is screwed in. At the same time, the locking nut 3 must be designed with a non-screwing groove of a certain height, and the diameter of the groove must be larger than the large thread diameter of the double-threaded bolt 1.

The above is just a kind of embodiment of the present utility model, a preferred example, the scope of protection of the utility model application is not limited to the described embodiment, all technical solutions equivalent to the present embodiment all belong to the protection scope of the present utility model .

Claims (3)

1. A set of fixed-torque anti-loosening locking bolts, which comprises bolts, fastening nuts, and locking nuts, is characterized in that, the tail of the bolt is provided with two sections of step-shaped fastening threads opposite in direction of rotation and Locking thread, the locking thread is arranged on the outside of the fastening thread, the upper end surface of the fastening nut matched with the fastening thread is provided with a waist-shaped annular boss that is sunken toward the center, on the lock The lower end surface of the tight nut is provided with a cylindrical boss matching the waist-shaped annular boss, and the height of the waist-shaped annular boss and the cylindrical boss is equal to the pitch of the locking thread. The annular boss and the cylindrical boss are interference fit, and the tolerance of the interference fit matches the locking torque. 2 . The fixed-torque anti-loosening locking bolt set according to claim 1 , wherein the pitch of the fastening thread is greater than that of the locking thread. 3 . 3 . The fixed-torque anti-loosening lock bolt set according to claim 1 or claim 2 , wherein the outer structures and dimensions of the fastening nut and the lock nut are exactly the same. 4 .