CN202188000U - Double-nut connecting bolt - Google Patents

Abstract

The utility model discloses a double-nut connecting bolt, which is composed of a screw rod, a flat washer, a fastening nut and a locking nut, and is characterized in that the radial dimension of the fastening nut is larger than the radial dimension of a standard nut with the same nominal diameter, and the axial thickness is larger than the axial thickness of a standard nut with the same nominal diameter. The cross-sectional area of the fastening nut is increased, the effective current-carrying cross-sectional area is increased, the contact resistance is reduced, the heat generation is reduced, the heat dissipation is increased, and the warping of the flat washer is overcome. The fastening nut is thickened, the torque force is increased, the pressure is increased, the thread is increased, and the thread is maintained for a long time without loosening. It is widely used in the power industry.

Description

A double nut connecting bolt

technical field

The utility model relates to a fastening part of electric equipment, in particular to a double-nut connecting bolt. the

Background technique

Generally, the bolt connection is composed of a screw, a nut, a spring washer and a flat washer. After the bolt is fastened to the workpiece, the nut does not move, but the spring washer has a large elastic force, and the material has a large internal stress. The lower surface of the cap and the upper surface of the flat pad generate pressure, and the flat pad transmits the pressure to the joint workpiece. There is also pressure equal to and opposite in direction between the flat pad and the workpiece. Since the spring washer is smaller than the flat washer, there is no pressure on the upper surface of the flat washer extending beyond the spring washer, so the flat washer is warped under the shear force of the workpiece upward and the spring washer downward, which leads to the contact surface deformation, the elastic force of the spring pad is released. After long-term operation, the contact surface is gradually deformed. As the spring pad gradually loses its elasticity, the crimping part becomes loose and the connection point is overheated. the

If the spring washer is canceled and the connection method of double nuts is used, in the connection position where vibration occurs frequently, the nut is easy to loose due to the lack of cushioning effect of the spring washer. After long-term operation, loosening of the crimping point and overheating of the connection point will also occur. . the

Contents of the invention

The purpose of this utility model is to solve the above-mentioned problems and provide a bolt that can not only overcome the deformation of the washer but also overcome the loosening caused by vibration. the

Realize the technical scheme of the present utility model is:

A double-nut connecting bolt is composed of a screw rod, a flat washer, a fastening nut and a locking nut, the radial dimension of the fastening nut is larger than that of a standard nut with the same nominal diameter, and the shaft The axial thickness is greater than the axial thickness of a standard nut of the same nominal diameter.

The screw is divided into a front part and a rear part, the diameter of the front part of the screw rod is smaller than that of the rear part of the screw rod, and the minimum inner diameter of the fastening nut is greater than the maximum outer diameter of the front part of the screw rod; the outer diameter of the front part of the screw rod and the rear part of the screw rod The thread direction is opposite; the internal thread of the fastening nut matches the external thread of the rear part of the screw, and the internal thread of the lock nut matches the external thread of the front part of the screw. the

The axial thickness of the fastening nut is preferably 1.2 times the axial thickness of the standard nut. the

The radial dimension of the fastening nut is preferably 1.2 times the radial dimension of the standard nut. the

The beneficial effects of the utility model are:

1. Increase the cross-sectional area of the fastening nut, increase the effective current-carrying cross-sectional area; reduce contact resistance; reduce heat generation; increase heat dissipation.

2. Thicken the fastening nut, increase the torque force, increase the pressure, increase the thread teeth, and keep it durable and not loose. the

3. Cancel the spring washer and increase the lock nut, and the internal thread of the lock nut is opposite to that of the fastening nut, so as to overcome the anti-warping of the flat pad; when the shock and vibration load is applied, the lock nut is used instead to be stable and reliable, eliminating The screw is loosened due to the cancellation of the spring washer; the lock nut replaces the spring washer of the ordinary bolt to increase the effective current-carrying cross-sectional area. the

Description of drawings

Figure 1 Schematic diagram of the connection structure of the utility model

Figure 2 Schematic diagram of the structure of the utility model embodiment

Symbols in the figure: 1—lock nut, 2—fastening nut, 3—flat washer, 4—screw, 5—workpiece, 6—first friction surface, 7—second friction surface, 8—front part of screw , 9—screw rod rear portion.

Detailed ways

As shown in Figure 1 and Figure 2: a double nut connecting bolt is composed of a screw rod 4, a flat washer 3, a fastening nut 2 and a locking nut 1, and the radial dimension ratio of the fastening nut 2 is The radial dimension of the standard nut with the same nominal diameter is 1.2 times larger, and the axial thickness is 1.2 times larger than the axial thickness of the standard nut with the same nominal diameter. Described screw rod is divided into screw rod front part 8 and screw rod rear part 9, and its screw rod front part 8 diameter is less than screw rod rear part 9 diameters, and the minimum inner diameter of fastening nut 2 is greater than the maximum outer diameter of screw rod front part 8; The direction of the external thread on the part 8 and the rear part 9 of the screw is opposite; the internal thread of the fastening nut 2 is compatible with the external thread of the rear part 9 of the screw, and the internal thread of the locking nut 1 is suitable for the external thread of the front part 8 of the screw match. the

Increase the cross-sectional area of the fastening nut 2 to increase the effective current-carrying cross-sectional area; reduce contact resistance; reduce heat generation; increase heat dissipation. Thicken the fastening nut 2, increase the torque force, increase the pressure, increase the thread teeth, and keep it durable and not loose. Cancel spring washer, add lock nut 1, and the internal thread of lock nut 1 is opposite to that of fastening nut 2, so as to overcome the anti-warping of flat pad; under the action of impact and vibration load, use lock nut 1 instead to be stable and reliable , to eliminate the loosening of the screws caused by canceling the spring washers; the lock nut 1 replaces the spring washers of ordinary bolts to increase the effective current-carrying cross-sectional area. the

The contact surface between the workpiece 5 and the fastening nut 2 is called the first friction surface 6 , and the contact surface between the fastening nut 2 and the locking nut 1 is called the second friction surface 7 . When impact and vibration loads are applied, the friction force of the first friction surface 6 decreases, and the fastening nut 2 tends to loosen, that is, the nut rotates clockwise. At this time, on the second friction surface 7, the lock nut 1 is subjected to the friction force of the fastening nut 2 so that it also has a tendency to rotate clockwise. Since the direction of rotation of the lock nut 1 is opposite to that of the fastening nut 1, Therefore, the loosening force of the fastening nut 1 is directly converted into the tightening force of the locking nut 1, thereby ensuring that the bolt does not loosen. the

Claims (4)

1. double nut attachment bolt; Be made up of screw rod, plain cushion, fastening nut and lock nut, it is characterized in that: the radial dimension of said fastening nut is bigger than the radial dimension of the standard cap of identical nominal diameter, axial thickness is bigger than the axial thickness of the standard cap of identical nominal diameter.

2. double nut attachment bolt according to claim 1 is characterized in that: said screw rod is divided into front and rear, and the anterior diameter of its screw rod is less than screw rod rear portion diameter, and the minimum diameter of fastening nut is greater than the anterior maximum outside diameter of screw rod; Said screw rod front portion is in the opposite direction with the outside thread on the screw rod rear portion; The internal thread of fastening nut and screw rod rear external thread are suitable, and the anterior outside thread of the internal thread of lock nut and screw rod is suitable.

3. double nut attachment bolt according to claim 1 and 2 is characterized in that: the axial thickness of said fastening nut is 1.2 times of axial thickness of standard cap.

4. double nut attachment bolt according to claim 1 and 2 is characterized in that: the radial dimension of said fastening nut is 1.2 times of radial dimension of standard cap.

Images