| 摘要 |
PURPOSE:To improve high-speed stability by providing a control valve controlled based on the car speed or the like on the discharge passage from a servo valve and providing two reaction chambers, with their opening areas controlled by this control valve and introduced with front and rear pressures of a variable orifice, on a reaction mechanism. CONSTITUTION:A power steering device 10 is constituted with a rotary valve member 31 relatively rotated by the rotation of an input shaft 23 and a sleeve valve member 32, and a servo valve 30 distributively controlling the pressure fluid to a power cylinder 90 is provided. In addition, a reaction mechanism 50 pressing a plunger 51 to the input shaft 23 and applying the steering reaction force is provided. In this case, a control valve 70 is provided on a discharge passage 74 from the servo valve 30 to a tank T. This control valve 70 is constituted so as to slide a valve plug 72 by the energizing force of a solenoid 80 energized in response to the input signal such as the car speed and to control the opening area of a variable orifice 76. Pressure chambers 54, 55 introduced with front and rear pressures of the variable orifice 76 are provided on the reaction mechanism 50 in front and rear of the plunger 51. |
