Views:7 Author:Site Editor Publish Time: 2020-06-05 Origin:Site
The joint bearing is a kind of spherical plain bearing. Its sliding contact surface is an inner sphere and an outer sphere. It can rotate and swing at any angle during movement. Do you know how to apply the joint bearing?
The joint bearing is widely used in engineering hydraulic cylinder, forging machine tools, engineering machinery, automation equipment, automobile shock absorber, hydraulic machinery and other industries. The joint bearings belong to spherical plain bearings. Its basic type is composed of inner and outer rings with a spherical sliding contact surface. According to its structure and type, it can bear radial load, axial load, or combined load of radial and axial simultaneous action.
Because the spherical sliding contact area of the spherical bearing is large, and the inclination angle is large, and most of the joint bearings adopt special processing methods, such as surface phosphating, galvanizing, chrome plating or external sliding surface lining, pad inlay, spraying, etc. Therefore, it has a large load capacity and impact resistance, and it has the characteristics of anti-corrosion, wear, self-aligning, good lubrication or no lubrication pollution. Even if the installation is misplaced, it can work normally. Therefore, the joint bearing is widely used in low speed swing motion, tilt motion and rotary motion.
The joint bearing has two spherical contact surfaces, which is called coordinated contact. The calculation method of the mechanical characteristics of the joint bearing plays an important role in the structural design and wear analysis of the shaft bearing. It is a very complex problem to calculate the contact pressure on the spherical surface. The existing Hertz model can not be used to calculate the contact pressure distribution on the spherical surface because it is limited to the elastic half space.
At present, there is already a unified model of spherical contact, namely the Fang model, which can better solve the problem of the contact pressure distribution of small deformation spherical surface. This model is applicable to both non-coordinated contact and coordinated contact. However, the contact area of the spherical bearing is not a complete spherical surface, and the calculation of its contact pressure distribution needs to be further calculated on the basis of the complete spherical coordinated contact model. In addition, the free boundary effect will also appear in the use of the car bearing, which will have a certain impact on the application of the joint bearing. The free boundary effect produces contact pressure concentration and large pressure gradient at the outer ring edge of the journal bearing.
Nowadays, there is a new type of rolling joint bearing structure, namely rod end joint bearing, which has the characteristics of simple structure, low friction coefficient, long service life and replaceable parts. It can replace the traditional joint bearing to achieve swing motion. The new bearing has a simple structure, and the swinging movement process is realized by the rolling contact friction movement of the needle bearing. Needle roller bearings are the key supporting parts for swinging motion. When the needle roller bearings wear out and fail, they can be removed and replaced.