Patent ID: 6052644
Filing Date: 2000-04-18
Classification: B60K,B60W,B60Y,F16H

Abstract:
An apparatus suitable for limiting a vehicle speed of a working vehicle, wherein the working vehicle includes:an accelerator pedal;a depressing stroke detector, for detecting a depressing stroke amount of said accelerator pedal;an engine control device, for outputting an accelerating signal based on a magnitude of a depressing stroke signal inputted from said depressing stroke detector; andan engine, a speed of which is controlled by said accelerating signal;said apparatus comprising:a vehicle speed detector, for detecting a vehicle speed of the working vehicle to output a vehicle speed signal; anda vehicle speed control device, connectable to said depressing stroke detector, said vehicle speed detector, and said engine control device, and having:a vehicle speed limit control means,an acceleration-deceleration/constant speed judging means, anda control gain changing means;wherein said vehicle speed limit control means:inputs said vehicle speed signal and said depressing stroke signal to compare said vehicle speed signal with a predetermined vehicle speed limit value,judges a vehicle speed limit traveling period, when said vehicle speed signal is equal to or greater than said predetermined vehicle speed limit value, to calculate a corrected depressing stroke signal by a control gain which obtains a correction amount of said depressing stroke signal, based on a deviation value between said vehicle speed signal and said predetermined vehicle speed limit value so that said deviation value becomes smaller, to output said corrected depressing stroke signal to said engine control device; andwherein said acceleration-deceleration/constant speed judging means:judges a stable vehicle speed period, when said deviation value in said vehicle speed limit traveling period is less than or equal to a predetermined value over a predetermined period of time, andjudges an acceleration-deceleration period, in a case other than said stable vehicle speed period, to output to said control gain changing means a result of a judgment by said acceleration-deceleration/constant speed judging means; andwherein said control gain changing means outputs, to said vehicle speed limit control means, a control gain in said stable vehicle speed period or a control gain in said acceleration-deceleration period, based on the results of the judgment by said acceleration-deceleration/constant speed judging means.