Propelling clutch apparatus for a working vehicle

摘要

A propelling clutch apparatus for a working vehicle comprises a friction type hydraulic clutch mounted on a propelling line, a valve for adjusting an oil pressure applied to the hydraulic clutch, a sensor for detecting angular acceleration of a rotary shaft included in the propelling line, and a control unit for controlling the hydraulic clutch in response to a change in a vehicle running state. The control unit effects controls in three stages. The first stage includes a preliminary step of narrowing spaces between friction disks of the hydraulic clutch by applying the oil pressure at a maximum level to the hydraulic clutch for a predetermined time from receipt of a clutch engaging command, and a subsequent main step of applying the oil pressure with predetermined characteristics. The second stage is for maintaining the hydraulic clutch in a half-clutch state when the angular acceleration in an accelerating direction or a decelerating direction reaches a predetermined value. The third stage is for fully engaging the hydraulic clutch.