SPEED CHANGE GEAR

摘要

PURPOSE:To prevent a speed change shock even if a sudden pressure increase is caused on the hydraulic clutch side without bad influence upon the whole hydraulic system even if the clutch pressure is increased by interposing a pressure regulating mechanism of a pressure reducing valve type in an oil path of a hydraulic clutch and providing an accumulator branching off a pilot oil path for increasing the spring pressure. CONSTITUTION:A pressure regulating mechanism F is interposed in an oil path 8 for operating a hydraulic clutch B. The mechanism is formed like a pressure reducing valve constructed so that as a pressure spring of an intermediate oil path 8a on the hydraulic clutch B side of the oil path 6 is increased more than the spring pressure, the pressure of the intermediate oil path 8a is let escape to the tank side. A pilot oil path 32 for increasing the spring pressure with an increase in pressure of the intermediate oil path 8a is formed. Further, an accumulator G for increasing and decreasing the capacity corresponding to a preset speed change step is provided branching off the pilot oil pressure 32.