A hydraulic motor is part of a hydraulic drive system that uses pressurized fluid to move a cylinder and make a machine function. An electric motor, combustion engine, or some other type of generator, pressurizes hydraulic fluid through a series of valves and pipes to control the system. This fluid physically pushes either a hydraulic cylinder or motor and drives the machinery. The motor itself is the actuator that converts the fluid's pressure into torque and rotation.
Gears can be added to a hydraulic motor to change the level of torque administered to a specific operation. For example, a military vehicle that needs to travel over many different types of land will have different gears to control the amount of pressure used to push the hydraulic motor. Pavement will need less hydraulic power to move the vehicle, while dirt or mud may need more.
Different types of plungers or pistons can be used in the motor. The most common type is an axial plunger. The pistons for the motor are designed to be parallel to allow for continuously adjustable sweeps to make the hydraulic motor operate more efficiently. Speed of the hydraulic motor ranges from 1200 to 1800 rpm. In order to increase the speed of a hydraulic motor, radial pistons can be used. These pistons make short sweeps in the engine, allowing for increased speed. However, the maximum level of torque decreases as an effect of these short sweeps.
One of the disadvantages of a hydraulic motor is that it allows for leakage through a connection in the drive system. This helps prevent the engine from locking up as it turns. This means that the motor needs some sort of braking mechanism to ensure that the system remains properly secure. It also requires routine monitoring of gauges that display the fluid levels. A safe operating system is important for the continued use of the machine.
First developed during the 1700s, hydraulic motors are notable for the fact that they can produce more power than other motors of the same size. They can take on larger loads than traditional electric motors and are most commonly used in aircraft, construction vehicles, and automobiles. In addition, a large volume of industrial machinery uses hydraulic motors to perform heavy lifting tasks and in situations that require strong pressurized actions such as injection moulding. These can be constructed as small components to a complex mechanism or one very large hydraulic motor performing a single task.