1. Hitachi excavator rotary buffer valve
When the swing control lever is pulled to the neutral position to stop the operation, the oil return line of the swing motor is blocked, and the oil pressure of the oil return line rises. At this time, it is still driven by the inertial force of the upper swing platform. Concave rotary motor, so it is called Zhuannaida to suck oil from the oil inlet to reduce the pressure of the oil inlet l. Then, the motor stops rotating, and the high oil pressure that appears at the oil return port pushes the motor back from the stop position until the pressure at the oil inlet and the oil return port is balanced, and the rotary motor repeats clockwise and counterclockwise synchronization. Rotation: The function of the same rotation buffer valve is to make the motor realize this kind of rotation conversion as soon as possible so that the upper interrotating platform can rotate smoothly.
Rotary cushion valve is composed of valve 1, valve 2, valve 3 and solenoid valve 4. The oil ports AM and BM are connected to the rotary motor and the pilot pressure oil that enters the valve 1 is sent to the oil port PS. The signal from the PVC causes the solenoid valve 4 to operate.
When the rotary joystick is in the neutral position (the rotary pressure switch is in the OF position) and the temperature of the hydraulic oil detected by the T sensor is higher than 20°C (68F), the engine controller (EC) does not send any signal to energize the solenoid valve 4. Therefore, the solenoid valve 4 is closed. Then, the valve 1 is opened to realize the function of slewing buffer.
When the rotary joystick is in the operating position (the rotary pressure switch is in the ON position) or the temperature of the hydraulic oil detected by the T sensor is lower than 20°C (68°C), the engine controller (EC) sends a signal to energize the solenoid valve 4, so , Solenoid valve 4 is activated. Then, the pilot oil flows from the oil port to the valve 1. It is closed, which eliminates the function of the swing buffer valve and restores the normal swing operation.
Rotary cushion valve is composed of valve 1, valve 2, valve 3 and solenoid valve 4. The ports AM and BM are connected to the swing motor. The pilot pressure oil entering valve 1 is sent to port PS. The signal from the PVC causes the solenoid valve 4 to operate.
When the rotary joystick is in the neutral position (the rotary pressure switch is in the OF position) and the temperature of the hydraulic oil detected by the T sensor is higher than 20°C (68F), the engine controller (EC) does not send any signal to energize the solenoid valve 4 , So the solenoid valve 4 is closed. Then, valve 1 is opened to realize the function of slewing buffer
When the rotary joystick is in the operating position (the rotary pressure switch is in the ON position) or the temperature of the hydraulic oil detected by the T sensor is lower than 20°C (68F), the engine controller (EC) sends a signal to energize the solenoid valve 4, so that, The solenoid valve 4 is activated. Then the pilot oil flows from the port four to the valve 1. Make it close, eliminate the function of the swing buffer valve, and restore the normal swing operation
2, rotary gearbox
The rotary reducer is a two-stage planetary gear reducer, and its structure is shown in Figure 5-11. The first-stage ring gear 2 and the second-stage ring gear 4 are installed in the housing. The shell is bolted to the main frame, so the ring gears 2 and 4 are fixed. The output shaft 10 of the rotary motor drives the first-stage sun gear 9 and the power is transmitted to the second-stage sun gear 7 through the first-stage planetary gear 1 and the planet carrier 8. The second-stage sun gear drives the transmission shaft 5 through the second-stage planetary gear 3 and the planet carrier 6.
The transmission shaft 5 meshes with the ring gear of the slewing bearing through gears, and the slewing bearing is connected to the base with bolts to drive the upper slewing platform to rotate.
