Patent ID: 7097021

Claim:
A running control device for a forklift comprising: a forward-reverse selected direction detection sensor which detects a traveling direction selected by forward-reverse selection means; a transmission which has a forward clutch and a reverse clutch that respectively switch the traveling direction of the vehicle to the forward direction and reverse direction, and which transmits a driving torque of an engine to drive wheels via the forward clutch and reverse clutch; a brake which applies a braking force to the vehicle; and a controller which outputs respective engaging force control commands to the forward clutch and reverse clutch of the transmission so that a magnitude of the vehicle driving torque is controlled by the control of engaging forces of the clutches, and which outputs a braking force control command to the brake to control the braking force, on the basis of signals indicating the selected traveling direction detected by the forward-reverse selected direction detection sensor; wherein a vehicle speed sensor that detects the vehicle speed of the forklift is provided, and the controller checks the selected traveling direction detected by the forward-reverse selected direction detection sensor, and, when the selected traveling direction is switched, outputs a first clutch pressure control command that disengages the forward clutch or reverse clutch of the transmission ( 19 ) and a first braking force control command that maintains a braking torque by the brake ( 23 ); when the vehicle speed detected by the vehicle speed sensor ( 13 ) becomes a specified vehicle speed α or less, outputs a second clutch pressure control command that gradually increases an engaging torque for the forward clutch or reverse clutch of the transmission ( 19 ) and a second brake pressure control command that gradually decreases the braking torque by the brake ( 23 ); at a specified time of t 0 prior to the point of time at which the vehicle speed reaches zero, outputs a third brake pressure control command that causes a braking torque by the brake ( 23 ) to be substantially zero; and when traveling direction of the forklift is reversed, outputs a third clutch pressure control command that gradually increases the engaging torque for the forward clutch or the reverse clutch of the transmission ( 19 ) until the clutch pressure is raised to 100%, whereby deceleration and acceleration of the forklift is maintained substantially constant during a period of time from the switching operation of traveling direction until a clutch pressure is raised to 100% after the reversal of the traveling direction.