SCREW TECHNOLOGY CO., LIMITED

SCREW TECHNOLOGY CO., LIMITED

Type of coupling, connected with ball screw

2021 11/23

Rigid coupling
The advantage of a rigid coupling is that it can accurately transmit torque, but the requirements for the concentricity of the two shafts are very high, that is to say, the two rotating shafts are required to be on the same straight line. If the concentricity deviation is too large, it will not only affect the coupling Its performance may even affect its lifespan. Rigid couplings can be divided into the following categories:

Sleeve coupling: The coupling connects two shafts in the form of a shaft sleeve. It has a simple structure, small size, and low price, but it is time-consuming and inconvenient to assemble and disassemble.
Clamp coupling, or split-muff coupling or compression coupling: A coupling is a clamp that can be opened and attached with bolts. The two shafts can be connected by locking bolts after installation. The advantage is that the coupling can be assembled or dismantled without moving the two shafts. However, the concentricity of the two shafts is low, the coupling structure is more complicated, and the balance accuracy is poor. good.
Flange coupling: The coupling is divided into two parts, both with flanges. When assembling, first fix the two parts of the coupling with the key and the shaft respectively, and then use the bolt to combine the two parts of the coupling. Its structure It is simple and can transmit large torque, but the requirements for the concentricity of the two shafts are also very high.
Flexible coupling
The flexible coupling allows torque to be transmitted when there is axial, radial or angular deviation. Examples are as follows:

Bushed pin type coupling (Bushed pin type coupling): consists of two shaft sleeves, one shaft sleeve is attached with a pin and a sleeve made of elastic material, the other has a corresponding pin hole, using a pin with an elastic sleeve To transmit torque, it is flexible in the axial direction and has good dynamic characteristics, but there may be a problem of different forces on each pin.
Universal joint: It is a joint that connects two rigid rods. The joint consists of a pair of ordinary hinges with a relative orientation of 90°. The two rigid rods can operate at any angle, but when the drive shaft rotates at a constant speed, the driven shaft There will be changes in movement.
Cross Slider Coupling: It is specially used in occasions where the drive shaft and the driven shaft are parallel and not collinear. The disk connected to the drive shaft and the drive shaft has corresponding tongue and grooves. When rotating, the slider disk will move radially.
Bellows coupling (Bellows coupling): Composed of bellows and shaft sleeve, simple structure, small backlash, but also small transmission torque.
Claw coupling: A cross-shaped elastic body is added between the two shafts of the coupling to increase flexibility and reduce vibration.
Thompson coupling: an improved double universal joint that can transmit torque at constant speed.
Disc coupling: A stainless steel disc spring (or two disc springs with a rigid intermediate block in between) is added between the two shafts of the coupling. It is commonly used in servo systems, but because of its precision, Improper installation or use can easily cause damage.
Diaphragm coupling (Diaphragm coupling): also known as a diaphragm coupling, uses a diaphragm as the elastic material in the coupling, and uses the deformation of the (metal) diaphragm of a specific shape to absorb the misalignment of the unit. The metal diaphragm can increase the rotational stiffness, and the plastic or rubber diaphragm can absorb vibration. It has the advantages of high strength, light weight, high power density, strong ability to compensate misalignment, and small additional force on the unit. It is especially suitable for high-speed and high-power turbo-compressor units that are sensitive to coupling weight and suspension bending moments.
Gear coupling: The gear is used as a power transmission method. The transmission torque is relatively large, but backlash and maintenance are the biggest problems.
Straight toothed rat tooth disc clutch
Torque limit coupling
The torque limiting coupling can protect the system from excessive torque.