JPH03128505U - - Google Patents

Description

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, FIG. 1 is a hydraulic circuit diagram showing the overall configuration of the vehicle suspension control device of the present invention, and FIG. 2 shows hydraulic pressure supplied to the control valve 16 shown in FIG. 1. A graph showing the relationship between the current value and the actuator pressure generated on the discharge side of the control valve 16 due to the current value, FIG.
6 is a block diagram showing the schematic configuration of the
5A to 5D are graphs showing the relationship between the current value supplied to the relief valve 30 shown in the figure and the relief pressure controlled by the relief valve 30 based on the current value. A flowchart showing the control procedure of the hydraulic pressure control executed by the control device 40, FIG. 6 is a timing chart showing the time change of the set pressure by the relief valve 30, and FIG. 7 shows the accumulator pressure (line pressure) PACC. 3 is a graph showing the relationship between relief pressures controlled by the relief valve 30. FIG. 4, 4F, 4R, 4FL, 4FR, 4RL, 4
RR...Oil passage, 6...Bypass passage (relief oil passage), 10...Oil pump, 12FL, 12F
R, 12RL, 12RR...Suspension unit, 13...Suspension spring, 14
... Hydraulic actuator, 15 ... Accumulator, 16 ... Control valve, 17 ... Oil passage, 18 ... Pilot check valve, 23 ... Check valve, 25
F, 25R...Accumulator, 27F, 27R
... Pilot check valve, 30 ... Relief valve, 32 ... Flow rate control valve, 36 ... Relief valve, 4
0...Electronic control unit, 42, 43...Pressure sensor.

Claims (1)

[Scope of utility model registration request] an oil pump that is constantly driven by the engine and generates working oil pressure; a hydraulic actuator that is interposed between the wheels and the vehicle body and maintains the vehicle height according to the magnitude of the supplied working oil pressure; and the hydraulic actuator and the oil. A control valve is disposed in the middle of the oil path connecting the pump and controls the supply and discharge of hydraulic pressure to the hydraulic actuator, and the oil path is branched between the oil pump and the control valve, and there is a control valve on the drain side from the oil pump. a bypass passage for discharging the hydraulic pressure of the oil pump; a relief valve means disposed in the bypass passage and capable of continuously changing and controlling the magnitude of the hydraulic pressure generated by the oil pump; the control valve and the bypass passage; an accumulator device connected to the oil path between the branch points where the oil pump branches, and accumulating the working hydraulic pressure generated by the oil pump; and check valve means for prohibiting the flow of hydraulic oil toward the direction, and the relief valve means is configured to control the oil pump when the accumulator pressure accumulated in the accumulator device reaches a first predetermined pressure. The hydraulic pressure to be generated is gradually reduced to a second predetermined pressure lower than the first predetermined pressure, while the accumulator pressure is lower than the first predetermined pressure.
The vehicle is characterized in that when the oil pump decreases to a third predetermined pressure that is lower than the second predetermined pressure and higher than the second predetermined pressure, the working oil pressure generated by the oil pump is gradually increased to the first predetermined pressure. Hydraulic suspension control device.