HYDRAULIC STEPLESS SPEED−CHANGE DEVICE AND POWER TRANSMISSION DEVICE

摘要

A hydraulic stepless speed−change device comprising a first variable capacity type hydraulic device provided with a first plunger and a plunger abutment and adapted to actuate the first plunger by the abutment, and a second hydraulic device provided with a second plunger and an output rotary section adapted to be rotated by abutting against the second plunger. The cylinder block is rotated around its axis and is provided with a first plunger hole and a second plunger hole for respectively receiving the first and second plungers. A hydraulic closed circuit connects the first and second plunger holes and causes the working oil to circulate between the first and second plunger holes. The stepless speed−change device has a distributing valve for controlling the circulation of the working oil in the hydraulic closed circuit, a valve hole formed in the cylinder block to receive the distributing valve, and a shaft extending through the cylinder block. The shaft and the cylinder block are synchronously rotated, and the output rotary section is supported for rotation around the shaft. The valve hole is formed in parallel with the shaft, and a constraining means is obliquely disposed with respect to the shaft and is rotated in synchronism with the cylinder block and reciprocates the distributing valve in its constrained state.