| 摘要 |
<p>PURPOSE:To prevent the occurrence of judder sounds and provide high transmissibility of power by providing a controlling means for reducing working oil pressure in a hydraulic clutch when rotational variation exceeds a predetermined value and increasing the working oil pressure when the rotational variation is less than the predetermined value. CONSTITUTION:A signal of a rotational frequency detecting means 91 consisting of an engine rotational frequency detector 16 provided between an engine 11 and hydraulic clutch 14 and a propeller shaft rotational frequency detector 18 provided between a speed change gear train 12a and a propeller 13 is inputted to a rotational variation detecting means 92 of a working oil pressure controlling means 23. A rotational variation signal obtained here is inputted together with a signal of a Ns setter 22 to a control section 93 which processes these signals in a predetermined manner to control a pressure adjusting means, i.e., pressure intensifying valve and pressure reducing valve by the output. A pressure reduction adjusting valve 35 for reducing the working oil pressure from the same oil pump 29 is controlled by the adjusting means to operate the hydraulic clutch 14 for slip control through a forward-backing change-over valve 60 changed over by a manual change-over means 94 or the like.</p> |
