Product Description

A hydraulic coupler is a mechanical device that uses a liquid medium to transmit rotational speed. Its driven input shaft is connected to the original drive, while its driven output shaft is connected to the load shaft. 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, akin to a rigid coupling. As pressure decreases, the output speed correspondingly drops. Continuously changing the medium pressure allows for stepless adjustment of the output speed below the input speed. The principle of power control and speed regulation for hydraulic couplers, as well as their efficiency, are based on the aforementioned characteristics. A hydraulic coupler is a power-consuming mechanical speed regulation device; the deeper the speed regulation (the lower the speed), the greater the loss, particularly for constant torque loads. Since the input power of the original transmission remains unchanged, the loss of power increases proportionally with the speed loss. For loads like fans and pumps, as the load torque varies with the square of the speed, the input power of the original transmission decreases at a rate proportional to the square of the speed, resulting in relatively smaller loss of power. However, the output power decreases at a cubic rate of the speed, and the speed regulation efficiency remains low. The speed regulation efficiency curve of hydraulic couplers 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 pump wheel and turbine of a hydraulic coupler form a sealed working chamber that allows for the cyclic flow of liquid. The pump wheel 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 liquid is ejected by the centrifugal pump wheel. This high-speed liquid, upon entering the turbine, drives it to rotate, transferring the energy obtained from the pump wheel to the output shaft. The liquid then returns to the pump wheel, creating a continuous flow. The hydraulic coupler transmits torque by changing momentum through the interaction between the liquid and the blades of the pump wheel and turbine. Its output torque is equal to the input torque minus the friction torque, thus its output torque is always less than the input torque. The input and output shafts of the hydraulic coupler are connected by the liquid, and there is no rigid connection between the working components. The characteristics of the hydraulic coupler include: the ability to eliminate shocks and vibrations; an output speed lower than the input speed, with the speed difference between the two shafts increasing with the load; good overload protection and starting performance, allowing the input shaft to continue rotating even when the load is too high and the output shaft stops, thus preventing damage to the power unit; when the load decreases, the output shaft speed increases until it approaches the input shaft speed. The transmission efficiency of the hydraulic coupler is equal to the ratio of the product of the output shaft speed and output torque (output power) to the product of the input shaft speed and input torque (input power). Generally, a hydraulic coupler can achieve higher efficiency when the normal operating speed ratio is above 0.95. The characteristics of the hydraulic coupler vary due to differences in the shape of the working chamber and the pump wheel and turbine. If the oil in the hydraulic coupler is drained, the coupler is disengaged, acting as a clutch.