“Coupling” is the word translated into Chinese, so as the name implies, a coupling is a mechanical device that transfers torque from one shaft to another. This article will introduce different types of couplings and their applications in detail. “.
In a machine, power is transmitted through a transmission or gear, which must be connected using parallel shafts. When the shafts are placed in a straight line and connected end-to-end to transmit torque, a coupling is used.
There are many types of couplings, including sleeve couplings, split couplings, flange couplings, bushing pin type flexible couplings, and hydraulic couplings. Details are as follows:
Sleeve couplings are simple hollow cylinders or pipes, as shown in the figure above. These couplings are manufactured based on the diameter of the shaft to ensure a good fit between the shaft and the sleeve. The driven shaft and drive shaft are inserted into both sides of the sleeve and fixed through bolt holes to ensure integral rotation to transmit torque. Sleeve couplings can withstand light and medium loads and are mainly used in applications where shaft alignment is not required.
Unlike sleeve couplings made from a single part, split couplings are designed with different parts, as shown in the figure above. Their sleeves are semi cylindrical in order to facilitate installation on both shafts. Split couplings are fixed by two rows of bolts and can be easily assembled or disassembled without changing the shaft position. This type of coupling is very suitable for medium speed, medium, and heavy loads.
Flange couplings are easy to manufacture and operate in a manner similar to sleeve couplings, with flanges at both ends of the sleeve and threaded holes for bolt connections. As shown in the figure above, there is also a key component on the shaft and hub to prevent slipping. Flange couplings are mainly used in medium and heavy industrial applications.
The bushing pin type flexible coupling is an improved version of the flange model, as shown above. This type uses rubber bushings to ensure that the bolts are perfectly installed in the bolt holes. Rubber bushings provide a degree of flexibility to absorb vibration, making these couplings more flexible and able to function even in the event of shaft misalignment. They are very common in medium-sized applications, especially in electronic motors.
The hydraulic coupling consists of a turbine and a pump, as shown in the figure above. These two parts have blades installed at a certain angle. The pump is located at the end of the drive shaft, and the turbine is located on the driven shaft. When the drive shaft rotates due to centrifugal force, fluid enters the pump through the center, introducing an additional component called a reactor between the turbine and the pump, which serves as a torque converter and as an alternative to manual clutches in automatic transmission systems. Hydraulic couplings are mainly used in industrial and marine applications, in which controlled starting of the transmission is crucial.