Product Description
A hydraulic coupling is a mechanical device that transmits rotational speed using a liquid medium. It connects the driving input shaft end to the original driving mechanism and the driven output shaft end to the load shaft end. By adjusting the pressure of the liquid medium, the rotational speed of the output shaft can be altered. In an ideal state, as the pressure approaches infinity, the output speed equals the input speed, similar to a rigid coupling. As the pressure decreases, the output speed correspondingly drops. Continuously changing the medium pressure allows for a stepless adjustment of the output speed below the input speed. The principle of power control and speed regulation, as well as the efficiency, of the hydraulic coupling are based on its aforementioned characteristics. The hydraulic coupler is an energy-consuming mechanical speed regulation device; the deeper the speed regulation (the lower the speed), the greater the loss, especially for constant torque loads. Since the original driving input power remains unchanged, the loss power increases proportionally with the speed loss. For loads like fans and pumps, where the load torque varies with the square of the speed, the original driving input power decreases with the square of the speed, resulting in relatively smaller loss power. However, the output power decreases with the cube of the speed, and the speed regulation efficiency is still very low. The speed regulation efficiency curve of the hydraulic coupling shows an average efficiency of around 50%. A non-rigid coupling that uses a liquid as the working medium, also known as a hydraulic coupling.
Product Real Photos
Product Features
The impeller and turbine of a hydraulic coupling form a sealed working chamber that allows for the circulation of fluid. The impeller is mounted on the input shaft, while the turbine is mounted on the output shaft. As the power unit (internal combustion engine, electric motor, etc.) rotates the input shaft, the fluid is ejected by the centrifugal impeller. This high-speed fluid, upon entering the turbine, drives it to rotate, transferring the energy obtained from the impeller to the output shaft. The fluid then returns to the impeller, creating a continuous cycle. The hydraulic coupling transmits torque by changing the momentum of the fluid interacting with the blades of the impeller and turbine. Its output torque is equal to the input torque minus the friction torque, hence it is always less than the input torque. The input and output shafts of the hydraulic coupling are connected by the fluid, with no rigid connections between the working components. The hydraulic coupling's features include: it can eliminate shocks and vibrations; the output speed is lower than the input speed, and the speed difference between the two shafts increases with the load; it has good overload protection and starting performance; when the load is too high and the shaft stops, the input shaft can still rotate without damaging the power unit; and when the load decreases, the output shaft speed increases until it approaches the input shaft speed. The transmission efficiency of the hydraulic coupling is equal to the ratio of the output shaft speed multiplied by the output torque (output power) to the input shaft speed multiplied by the input torque (input power). Generally, a hydraulic coupling can achieve higher efficiency when the normal operating speed ratio is above 0.95. The characteristics of the hydraulic coupling vary due to the different shapes of the working chamber and the impeller and turbine. If the oil in the hydraulic coupling is drained, the coupling is disengaged, serving as a clutch.
