What is a Universal Joint?

The so-called universal joint refers to a mechanical structure that uses a ball-type connection to realize the power transmission of different shafts, which is a very important part of the equipment and belongs to the hydraulic parts. The combination of universal joint and drive shaft is called universal joint transmission. On vehicles with front engine rear wheel drive, the universal joint transmission is installed between the transmission output shaft and the drive axle main reducer input shaft; while vehicles with front engine front wheel drive omit the drive shaft and the universal joint is installed between the front axle half shaft, which is responsible for both driving and steering, and the wheels.

In the equipment driveline and other systems, in order to achieve some axis intersection or relative position often change the power transmission between the axis, must use universal transmission device. Universal transmission generally consists of universal joints and drive shafts, sometimes with intermediate support, mainly for the following positions: 1 - universal joint; 2 - drive shaft; 3 - front drive shaft; 4 - intermediate support.

Between the transmission and the drive axle of the engine front and rear wheel drive equipment. When the distance between the transmission and the drive axle is far, the driveshaft should be divided into two or even more sections and intermediate supports should be added. Between the distributor and the drive axle or between the drive axle and the drive axle for multi-axle-driven equipment. Due to the deformation of the frame, it will cause mutual position changes between the axles between the two transmission components of the universal joint fit between. Shown is between the engine and transmission.

Between the differential of the equipment with independent suspension and the differential. Between the differential of the steering drive axle and the wheels. In the power output unit and steering maneuvering mechanism of the equipment.

Universal Joint Fit

In a universal joint fit, the rotation of one part (output shaft) around its own axis is driven by the rotation of another part (input shaft) around its axis.

Universal joint is the universal joint, is to achieve variable angle power transmission machine parts, for the need to change the direction of the transmission axis position, it is the equipment drive system of the universal transmission device "joint" parts. Universal joint and drive shaft combination, called universal joint transmission device.

The structure and role of the universal joint is somewhat like the joints on the human limbs, which allows the angle between the connected parts to vary within a certain range. In order to meet the power transmission, adapt to the steering and equipment running up and down jump caused by the angle change, front drive equipment drive axle, half-shaft and wheel axle is often connected to the universal joint. However, due to the limitations of the axial size, the required deflection angle is relatively large, a single universal joint can not make the output shaft and the shaft into the shaft of the instantaneous angular velocity equal, easy to cause vibration, aggravate the damage to the components, and generate a lot of noise, so a wide variety of equal-speed universal joint. In the front drive equipment, each half-axle uses two equal-speed universal joints, the universal joint near the variable-speed drive axle is the inner half-axle universal joint, and the one near the axle is the outer half-axle universal joint. On rear drive equipment, the engine, clutch and transmission are mounted on the frame as a whole, while the drive axle is connected to the frame by elastic suspension, and there is a distance between them that needs to be connected. Equipment running road surface unevenness to produce jump, load changes or two assemblies installed bit difference, etc., will make the transmission output shaft and drive axle main reducer input shaft between the angle and distance changes, so in the rear drive equipment universal joint drive form are used double universal joint, is the drive shaft ends have a universal joint, its role is to make the drive shaft ends of the angle equal, so as to ensure that the output shaft and input shaft The function is to make the drive shaft ends of the angle equal, so as to ensure that the instantaneous angular velocity of the output shaft and input shaft is always equal.

Classification of Universal Joints

The universal joint can be divided into rigid universal joint and flexible universal joint according to whether the joint has obvious elasticity in the direction of torsion. Rigid universal joint can be divided into unequal velocity universal joint (commonly used for cross shaft type), quasi-equal velocity universal joint (such as double joint universal joint) and equal velocity universal joint (such as ball cage type universal joint).