What is the difference between a hydraulic pump and a hydraulic motor?

Hydraulic pumps and hydraulic motors are essential hydraulic components on every excavator. The structure and working principle are very similar. Some small whites outside the industry sometimes confuse these two things. Some people say that hydraulic pumps and hydraulic motors are like a pair of lovers, one attack and one attack; some people say that hydraulic pumps and hydraulic motors like generators and motors, one identity two positions. Is this description right? What is the difference between the two?

Similarities between hydraulic motors and hydraulic pumps:

(1) In principle, the hydraulic motor and the hydraulic pump are reversible. If the motor is driven, the output is hydraulic energy (pressure and flow), which is the hydraulic pump; if the pressure oil is input, the output is mechanical energy. The moment and speed) become hydraulic motors.

(2) From a structural point of view, the two are similar.

(3) In terms of working principle, both of them use the change of the sealed working volume to absorb oil and discharge oil. For the hydraulic pump, the oil is sucked when the working volume is increased, and the high pressure oil is discharged when the working volume is decreased. For the hydraulic motor, the high pressure oil is entered when the working volume is increased, and the low pressure oil is discharged when the working volume is decreased.

The difference between hydraulic motor and hydraulic pump:

(1) The hydraulic pump is an energy device, and the hydraulic motor is an actuator. The hydraulic pump is a conversion device that converts the mechanical energy of the motor into hydraulic energy. The output flow and pressure are expected to be high in volumetric efficiency. The hydraulic motor is a device that converts the pressure energy of the liquid into mechanical energy, and outputs torque and rotational speed, and the mechanical efficiency is desired.

(2) The steering of the output shaft of the hydraulic motor must be able to rotate forward and reverse, so its structure is symmetrical; and some hydraulic pumps (such as gear pumps, vane pumps, etc.) have clear regulations for steering, only one-way rotation, You cannot change the direction of rotation at will.

(3) In addition to the inlet and outlet ports, the hydraulic motor also has a separate leakage port; the hydraulic pump generally only has inlet and outlet ports (except for the axial piston pump), and the leakage oil inside is connected to the inlet port.