| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To solve the following problem: when a brake switch is turned on and a clutch is simultaneously disconnected while a vehicle runs on a slope, there may exist slight slip-down on the slope so that the clutch is disconnected before generating required braking force necessary for braking the vehicle. <P>SOLUTION: A hydraulic mechanical transmission provides a hydraulic transmitting portion using a hydraulic continuously variable transmission mechanism (HST21), and a differential mechanism (10) using a planetary gear connected with both the hydraulic transmitting portion and a mechanical transmitting portion. A HST speed change ratio is decreased from a predetermined value to an approximately zero, or the HST speed change ratio is increased from an approximately zero to the predetermined value. A HST speed change ratio controlling curve as a function between the HST speed change ratio and time is set up and registered in advance, and the HST speed change ratio is changed and controlled along the HST speed change ratio controlling curve when the brake switch 96 operated by a brake operating means (35) is turned on or off. <P>COPYRIGHT: (C)2004,JPO&NCIPI</p> |
