SIGNAL PRESSURE DELAY DEVICE

PURPOSE: To simplify an oil passage structure by lapping notches of a spool with a sleeve land at a neutral position, interrupting an oil passage in the spool, arranging a throttle composed of a notch and a circular groove, and releasing an oil passage in the spool through the throttle when the spool is moved. CONSTITUTION: Notches 4a, 4b of a spool 1 are lapped over a land 6 of a sleeve 3 at a neutral position. An inner spool oil passage 5a is not communicated, for generating no flow of pressure oil. when the spool 1 is moved against a first spring 2a, a throttle composed of the first notch 4a and a first circular groove 8a is opened. The pressure oil flows sequentially through the oil passage 5a in the first spool, a through-hole 7a, the first notch 4a, the first circular groove 8a, a through-hole 7b, and an oil passage 5b in a second spool. Spring reaction of a first spring 2a determines cracking pressure, and delay of signal pressure is determined by throttle. The same is true in the case that the pressure oil flows in an opposite direction. Both direction flow is attained by a common oil passage, so that whole of a device is downsized.