Product Introduction

A hydraulic coupler is a mechanical device that transfers rotational speed using a liquid medium. Its driving input shaft is connected to the original drive, while the 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. Ideally, as the pressure approaches infinity, the output speed equals the input speed, akin to a rigid coupling. As pressure decreases, the output speed correspondingly reduces. Continuously changing the medium pressure allows for variable speed adjustment below the input speed. The principle of power control and speed regulation of a hydraulic coupler, along with its efficiency, is based on the aforementioned characteristics. A 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 drive input power remains constant, 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 drive input power decreases with the square of the speed, resulting in relatively lower loss power. However, the output power decreases cubically with the speed, and the speed regulation efficiency remains low. The speed regulation efficiency curve of a hydraulic coupler shows an average efficiency of around 50%. A non-rigid coupling that operates with a liquid as the working medium, also known as a hydraulic coupling.

Product Actual Photos

Product Features

The impeller and turbine of a hydraulic coupling form a sealed working chamber that allows for the circulating flow of liquid. The impeller is mounted on the input shaft, while the turbine is mounted on the output shaft. As the power unit (such as an internal combustion engine or electric motor) drives the input shaft to rotate, the liquid is ejected by the centrifugal impeller. This high-speed liquid enters the turbine, causing it to rotate and transferring the energy obtained from the impeller to the output shaft. The liquid then returns to the impeller, creating a continuous flow cycle. The hydraulic coupling transmits torque by changing the momentum moment through the interaction between the liquid and 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 liquid, and there is no rigid connection between the working components. The hydraulic coupling features the ability to eliminate shock and vibration; the output speed is lower than the input speed, and the speed difference between the two shafts increases with the load; excellent overload protection and starting performance; when the load is too high and the rotation stops, the input shaft can still rotate without causing damage to 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 high 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, acting as a clutch.