Control valve and fluid motor arrangement

Claim 1

In combination, 1. a control valve for a rotary type hydraulic servo-actuating mechanism, comprising a. a hollow casing with a portion of one end defined as a valve portion, and at the other end a portion defined as a manifold portion, said manifold portion having passage means adapted to be connected to the hydraulic servo-actuating mechanism, and said casing further having in the valve portion a pressurized oil feeding port and a pressurized oil discharging port, and b. a spindle concentrically mounted in said hollow casing in a freely slidable and rotatable manner, said spindle having a pair of oil paths extending axially within said spindle from said valve portion to said manifold portion, long grooves spirally formed on the outer periphery of said spindle open to said valve portion, and radially extending oil paths connecting said axial oil paths with said long grooves; and 2. a feedback mechanism comprising a. a first pulley fitted on one end of said hollow casing, b. a rotary shaft adapted to be driven by the rotary type hydraulic servo-actuating mechanism, c. a second pulley mounted on said rotary shaft, said second pulley being disposed in alignment with said first pulley, and d. a belt tensioned between said pulleys, whereby the motion derived from the rotary type hydraulic servo-actuating mechanism is fed back to the control valve.