Pre-tightening force applying device for over-screwing and under-screwing high-strength bolt

Abstract

The utility model belongs to the technical field of bolt tightening devices, and particularly relates to an over-screwing and under-screwing high-strength bolt pre-tightening force applying device which comprises an electric drill, a drill bit is installed at one end of the electric drill, at least two sliding frames are assembled at one end of the electric drill and located on the outer side of the drill bit, and lengthening frames are assembled at the ends, away from the electric drill, of the sliding frames through clamping structures. A clamping plate is arranged on the inner side of the end, away from the sliding frame, of the lengthened frame, a plurality of clamping teeth are arranged on the inner side of the clamping plate, and an attaching assembly is installed between the sliding frame and the electric drill, used for driving the sliding frame and the lengthened frame to be attached to the bolt and comprises at least one sliding strip arranged in the electric drill. The sliding frame located on the inner side of the electric drill is slidably connected with the sliding strip, and a sliding groove is formed between the electric drill and the sliding frame. According to the utility model, the tightening angle of the bolt can be automatically controlled while the pre-tightening force is applied, so that the bolt stops rotating between over-tightening and under-tightening, and the pre-tightening force of the bolt is ensured to be within a reasonable range.

Description

Technical Field

[0001] The utility model belongs to the technical field of bolt tightening devices, and particularly relates to a pre-tightening force applying device for over-tightened and under-tightened high-strength bolts. Background Art

[0002] The pre-tightening force applying device for high-strength bolts is a tool for applying pre-tightening force to high-strength bolts, and generally has two types: torque type and tension type.

[0003] The torque type pre-tightening force applying device generates pre-tightening force by applying torque to the nut or bolt head. Common ones include torque wrenches, twist-off type high-strength bolts, etc. The advantages of the torque type pre-tightening force applying device are simple structure, convenient operation, and low cost. However, the disadvantages are that the pre-tightening force is not easy to control, and it is greatly affected by factors such as thread friction, bolt material, and surface treatment, which easily cause over-tightening or under-tightening of the bolts.

[0004] After retrieval, the main problem of the existing pre-tightening force applying devices for high-strength bolts is that the torque type pre-tightening force applying device cannot accurately control the pre-tightening force, easily causes over-tightening or under-tightening of the bolts, and affects the performance and service life of bolt connections.

[0005] Therefore, aiming at the problems of the existing pre-tightening force applying devices for high-strength bolts, it is necessary to develop a pre-tightening force applying device for over-tightened and under-tightened high-strength bolts. Content of the Utility Model

[0006] The purpose of the utility model is to provide a pre-tightening force applying device for over-tightened and under-tightened high-strength bolts, which can automatically control the tightening angle of the bolt while applying the pre-tightening force, make the bolt stop rotating between over-tightening and under-tightening, and ensure that the pre-tension of the bolt is within a reasonable range.

[0007] The technical solution adopted by the utility model is specifically as follows:

[0008] A pre-tightening force applying device for over-tightened and under-tightened high-strength bolts includes an electric drill. One end of the electric drill is installed with a drill bit. At least two sliding frames are assembled on one end of the electric drill and located outside the drill bit. One end of the sliding frame away from the electric drill is assembled with an extension frame through a clamping structure. The inner side of the end of the extension frame away from the sliding frame is provided with a clamping plate, and the inner side of the clamping plate is provided with a plurality of clamping teeth.

[0009] A close-fitting component is installed between the sliding frame and the electric drill, and the close-fitting component is used to drive the sliding frame and the extension frame to closely fit the bolt.

[0010] The clamping component includes at least one sliding bar arranged inside the electric drill. The sliding frame located inside the electric drill is slidably connected to the sliding bar. A sliding groove is arranged between the electric drill and the sliding frame, and the width of the sliding groove is greater than the width of the sliding frame. A spring is arranged inside the electric drill and is connected to the sliding frame.

[0011] The clamping structure includes a lengthening bar extending from the lengthening frame. The lengthening frame and the lengthening bar are inserted into the inside of the sliding frame. The lengthening frame and the sliding frame are in interference fit. A plurality of clamping blocks are arranged on the outer side of the lengthening bar, and clamping grooves are arranged at positions corresponding to the clamping blocks on the inner side of the sliding frame.

[0012] A contact soft pad is arranged at one end of the clamping plate away from the sliding frame.

[0013] An inclined surface is arranged on the inner side between the lengthening frame and the clamping plate.

[0014] The clamping block is made of a flexible material.

[0015] The technical effects achieved by the present utility model are as follows:

[0016] The present utility model can automatically control the tightening angle of the bolt while applying a pre-tightening force, stop the rotation of the bolt between over-tightening and under-tightening, ensure that the pre-tension of the bolt is within a reasonable range, and improve the reliability and safety of bolt connection. Description of the Drawings

[0017] Figure 1 is a schematic structural diagram of the present utility model;

[0018] Figure 2 is a schematic structural diagram among the lengthening frame, the inclined surface and the clamping teeth in the present utility model;

[0019] Figure 3 is a cross-sectional view of the electric drill in the present utility model;

[0020] Figure 4 is in the present utility model Figure 3 is an enlarged view of part A in.

[0021] In the drawings, the list of components represented by each reference numeral is as follows:

[0022] 1. Electric drill; 2. Drill bit; 3. Sliding frame; 4. Lengthening frame; 5. Clamping plate; 6. Clamping teeth; 7. Contact soft pad; 8. Inclined surface; 9. Sliding bar; 10. Spring; 11. Lengthening bar; 12. Clamping block; 13. Clamping groove; 14. Sliding groove. Detailed Embodiment

[0023] In order to make the purpose and advantages of the present utility model more clear and understandable, the present utility model will be specifically described below in conjunction with embodiments. It should be understood that the following text only describes one or several specific implementation manners of the present utility model, and does not strictly limit the scope of protection of the specific claims of the present utility model.

[0024] As Figures 1-4 shown, a device for applying pre-tightening force to an over- or under-tightened high-strength bolt includes a drill 1. One end of the drill 1 is equipped with a drill bit 2. When the drill 1 works, the drill bit 2 is connected to the bolt to be tightened. By starting the drill 1, the bolt to be tightened can be fastened to other objects through the drill bit 2. At least two sliding frames 3 are assembled on one end of the drill 1 and located outside the drill bit 2. One end of the sliding frame 3 away from the drill 1 is assembled with an extension frame 4 through a clamping structure. The inner side of one end of the extension frame 4 away from the sliding frame 3 is provided with a clamping plate 5. An inclined surface 8 is arranged inside between the extension frame 4 and the clamping plate 5. Through the arrangement of the inclined surface 8, the head of the bolt can slowly contact the clamping plate 5 through the inclined surface 8, thereby preventing the head of the bolt from being stuck. The width of the clamping plate 5 is greater than the width of the extension frame 4, and the outer side of the clamping plate 5 is flush with the extension frame 4. The thickness of the inner side of the clamping plate 5 is greater than the thickness of the extension frame 4. A plurality of teeth 6 are arranged on the inner side of the clamping plate 5. The teeth 6 and the object to be processed are mutually attached through a contact soft pad 7. Furthermore, when the head of the bolt contacts the teeth 6, it will prevent the bolt from continuing to rotate, so as to be able to adapt to the pre-tightening force between the bolt and the object to be processed. A contact soft pad 7 is arranged at one end of the clamping plate 5 away from the sliding frame 3. Through the arrangement of the contact soft pad 7, when the contact soft pad 7 contacts the object to be processed when the clamping plate 5 contacts it, the contact soft pad 7 contacts it first, avoiding damage to the object to be processed caused by the direct contact of the clamping plate 5 with it;

[0025] A close-fitting component is installed between the sliding frame 3 and the drill 1. The close-fitting component is used to drive the sliding frame 3 and the extension frame 4 to closely fit the bolt.

[0026] Referring to the attached Figure 3 , the close-fitting component includes at least one sliding bar 9 arranged inside the drill 1. The sliding frame 3 located inside the drill 1 is slidably connected to the sliding bar 9. When the sliding frame 3 and the sliding bar 9 are slidably connected to each other, the situation that the sliding frame 3 is skewed can be avoided, and further the situation that the external extension frame 4 follows and is skewed can be avoided. A sliding groove 14 is arranged between the drill 1 and the sliding frame 3, and the width of the sliding groove 14 is greater than the width of the sliding frame 3. Through this setting, the sliding frame 3 can slide inside the sliding groove 14. A spring 10 is arranged inside the drill 1, and the spring 10 is connected to the sliding frame 3;

[0027] Through the above description, when it is necessary to fasten a bolt, the bolt can be rotated by the drill bit 2 to achieve the fastening effect. When the head of the bolt is about to contact the object to be processed (generally, the diameter of the head of the bolt is a little larger than that of the body), it first contacts the inclined surface 8, and contacts the clamping plate 5 and the teeth 6 through the inclined surface 8. When contacting the inclined surface 8, the spring 10 can be compressed, and then the two sliding frames 3 move in a direction away from each other until the head of the bolt contacts the teeth 6. At this time, due to the arrangement of the spring 10, the spring 10 can drive the clamping plate 5 and the teeth 6 to clamp the head of the bolt, thereby restricting the rotation of the bolt. The teeth 6 are fixed obliquely inside the clamping plate 5, and the inclination is opposite to the rotation direction of the bolt, so that the teeth 6 can further restrict the head of the bolt, so that after the bolt rotates to a certain depth, its rotation is restricted, so that the bolt stops rotating between over-tightening and under-tightening, and stops rotating within the pre-tension value.

[0028] Refer to the attached Figure 3 and the attached Figure 4 , the clamping structure includes a long strip 11 extending from the extension frame 4, and the extension frame 4 and the long strip 11 are inserted into the inside of the sliding frame 3. The extension frame 4 and the sliding frame 3 are in interference fit. The extension frame 4 and the sliding frame 3 can be in interference fit through a material such as rubber. Then, after the extension frame 4 is inserted into the inside of the sliding frame 3, the movement of the extension frame 4 is restricted. A plurality of clamping blocks 12 are arranged on the outer side of the long strip 11, and clamping grooves 13 are arranged at positions corresponding to the clamping blocks 12 on the inner side of the sliding frame 3. The clamping blocks 12 are made of flexible material. Through this setting, the clamping blocks 12 can deform when inserted into the inside of the sliding frame 3 and can move into the inside of the clamping grooves 13 when contacting the clamping grooves 13;

[0029] According to the above description, after the extension frame 4 and the long strip 11 are inserted into the inside of the sliding frame 3, the movement of the extension frame 4 is restricted by the interference fit between the extension frame 4 and the inner side of the sliding frame 3. And through a plurality of clamping blocks 12 respectively inserted into the inside of the clamping grooves 13, the movement of the extension frame 4 is further restricted, thus realizing the installation and fixation of the extension frame 4 on the sliding frame 3. When it is necessary to drill or fasten other bolts or other objects, the extension frame 4 can be removed to avoid interfering with the use of the electric drill 1.

[0030] The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and retouches can be made, and these improvements and retouches should also be regarded as the protection scope of the present invention. The structures, devices and operation methods not specifically described and explained in the present invention, unless otherwise specified and limited, are implemented according to the conventional means in the art.

Claims

1. A device for applying pre-tightening force to over-tightened high-strength bolts, comprising an electric drill (1), characterized in that: A drill bit (2) is installed at one end of the electric drill (1); at least two sliding frames (3) are installed at one end of the electric drill (1) and outside the drill bit (2); an extension frame (4) is installed at one end of the sliding frame (3) away from the electric drill (1) through a clamping structure; a clamping plate (5) is arranged on the inner side of the end of the extension frame (4) away from the sliding frame (3); and a plurality of clamping teeth (6) are arranged on the inner side of the clamping plate (5); A close fitting assembly is installed between the sliding frame (3) and the electric drill (1), and the close fitting assembly is used to drive the sliding frame (3) and the extension frame (4) to close the bolts.

2. The device for applying pre-tightening force to over-tightened high-strength bolts according to claim 1, characterized in that: The clamping component comprises at least one sliding bar (9) arranged inside the electric drill (1); the sliding frame (3) located inside the electric drill (1) is slidably connected to the sliding bar (9); a sliding groove (14) is arranged between the electric drill (1) and the sliding frame (3); the width of the sliding groove (14) is greater than the width of the sliding frame (3); a spring (10) is arranged inside the electric drill (1), and the spring (10) is connected to the sliding frame (3).

3. The pre-tightening force applying device for over-tightened high-strength bolts according to claim 1, characterized in that: The clamping structure comprises an extension strip (11) extending from an extension frame (4), and the extension frame (4) and the extension strip (11) are inserted into the interior of the sliding frame (3), the extension frame (4) and the sliding frame (3) are interference fit, a plurality of clamping blocks (12) are arranged on the outer side of the extension strip (11), and a clamping groove (13) is arranged on the inner side of the sliding frame (3) and at a position corresponding to the clamping block (12).

4. The device for applying pre-tightening force to over-tightened high-strength bolts according to claim 1, characterized in that: A contact pad (7) is provided at one end of the clamping plate (5) away from the sliding frame (3).

5. The device for applying pre-tightening force to over-tightened high-strength bolts according to claim 1, characterized in that: An inclined surface (8) is provided on the inner side between the extension frame (4) and the clamping plate (5).

6. The device for applying pre-tightening force to over-tightened high-strength bolts according to claim 3, characterized in that: The card block (12) is made of flexible material.

Images