1. The structure of the rotary motor
The structure of the rotary motor includes a housing, a cylinder, a plunger, a balance valve, a valve plate, a brake, and so on. Its function is that the slewing motor drives the upper car body to slew through the planetary gear reduction mechanism.
(2) Working principle of slewing motor
Motor working principle:
The slewing motor is a swash plate type plunger motor, which generates torque by applying high-pressure hydraulic oil to the reciprocating plunger.
T(torque)=△P×V(row)÷2Ⅱ
(3) Working process of slewing motor
Slewing start work (action)
①The pilot joystick makes a right turn operation
②The high-pressure oil from the main pump is supplied to the MA port through the main valve
③ The MA port pressure rises and the motor starts to rotate
④The low-pressure oil from the motor returns to the tank through the main valve from port B. Note: Red is high pressure, green is low pressure
When the rotation stops, the main valve cuts off the motor's inlet and outlet circuits, but the motor will still rotate due to the inertial force. Therefore, the pressure on the MB side of the motor will rise sharply, relying on the back pressure to brake. If the pressure is abnormally high, the motor will be damaged. At this time, the abnormally high-pressure oil will flow from the motor outlet end (high-pressure end) to the low-pressure end, thereby preventing damage to the motor.
