JPS642673U - - Google Patents

Description

[Brief explanation of the drawing]

1 to 5 show an embodiment of a hydraulic reaction force type power steering device according to the present invention, and FIG. 1 is a diagram showing the overall configuration of a hydraulic reaction force type power steering device to which the present invention is applied. , Figure 2 is an overall sectional view of the power steering device main body,
Fig. 3 is a sectional view of Fig. 2, Fig. 4 is a characteristic diagram of reaction force passage flow rate and reaction force pressure, Fig. 5 is a characteristic diagram of gear generation pressure with respect to handle torque, and Fig. 6 is a diagram of the conventional technology. 4 is a diagram corresponding to FIG. 4, and FIG. 7 is a diagram corresponding to FIG. 5 of the prior art. Explanation of symbols, 10... Supply pump, 13... Servo valve passage, 14... Reaction force passage, 17... Power cylinder, 18... Solenoid control valve, 20... Diversion valve, 21... Casing, 22... ...Inner hole, 25...
Valve spool, 28... Spring, 29... Control orifice, 30... Input room, 31... Control room,
32...First output chamber, 33...Second output chamber, 34
...first variable aperture section, 35...second variable aperture section,
50...Servo valve, 60...Reaction force mechanism.

Claims (1)

[Scope of utility model registration request] A servo valve that controls the supply and discharge of working fluid to a power cylinder that is activated based on the relative rotation of the input and output shafts and generates assist force, and a torsion spring characteristic between the two shafts depending on the applied pressure. a reaction force mechanism that changes the assist force by changing the assist force, and a flow divider valve that divides working fluid from the supply pump into a servo valve passage connected to the servo valve and a reaction force passage connected to the reaction force mechanism. , an electromagnetic control valve provided in the reaction passageway to control reaction force pressure applied to the reaction force mechanism according to running conditions such as vehicle speed; the diversion valve includes a casing having an inner hole; An input chamber and a control chamber are fitted into the hole so as to be slidable in the axial direction and communicated with the supply pump inside the inner hole, a first output chamber is communicated with the servo valve passage, and the reaction force passage is communicated with the input chamber. a spring that biases the valve spool in one axial direction; a control orifice formed between the input chamber and the control chamber; and a control orifice formed between the input chamber and the first output chamber. The valve spool includes a first variable throttle section formed between the chambers and a second variable throttle section formed between the control chamber and the second output chamber, and the valve spool is configured to move between the first and second output chambers by moving in its axial direction. 2. In the hydraulic reaction force type power steering device configured to increase and decrease the opening areas of the variable throttle parts in opposite directions, the spring constant of the spring constituting the flow dividing valve is increased and the initial installation load is decreased. A hydraulic reaction force type power source characterized in that the flow dividing characteristics of the flow dividing valve are set so that as the gear generation pressure generated in the servo valve passage increases, the flow dividing ratio to the reaction force passage becomes gentle and the slope gradually decreases. Steering device.