| 摘要 |
<p>PURPOSE: To use a small diameter output driven hydraulic retarder by using a friction brake to be used for generating a low forward drive ratio for speed reduction at other forward drive ratioes. CONSTITUTION: Cooling and circulation flow is established by a cooling means having a passage 90 and a throttle part 91 provided in a hydraulic retarder supply passage 74. This passage 90 is pressurized only when fluid is utilized for cooling and lubricating a friction brake 14 as the hydraulic speed reducer supply passage 74 is pressurized when actuation of a hydraulic retarder 26 is necessary. The passage 90 communicates fluid with at least one nozzle, that is a liquid discharging passage 92 provided in a housing for the friction brake 14. The liquid discharging passage 92 is normally closed by a plate 94 as an extended part of a secondary piston 84. As the secondary piston 84 moves left, the plate 94 also moves left, and a friction disc 32 of the friction brake 14 is partially engaged with a plate 36.</p> |
