CONTROL METHOD FOR V-BELT TYPE STEPLESS TRANSMISSION GEAR BOX

摘要

PURPOSE:To improve the response of speed-change in a device controlling the gaps of V-belt grooves of pulleys by means of a speed-change control valve operated by a speed-change motor by controlling the rotational speed of the speed-change motor to be increased when a sudden speed-change is required. CONSTITUTION:A captioned transmission gear box obtains the speed-changing work by varying the width of V-shaped pulley grooves between fixed and movable cone plates 26 and 30 and between 42 and 46 of pulleys 24 and 34 by pressurized oil supplied to a cylinder chamber 28 of the drive pulley 24 provided on a drive shaft 22 driven by an engine and a cylinder chamber 44 of the driven pulley 34 provided on a driven shaft 40 via a speed-change control valve 106. The speed-change control valve 106 is controlled by a speed-change motor 110 via a speed-change operation mechanism 112. In this case, the rotational speed of the speed-change motor 110 is controlled to be increased when the difference between the actual rotation position and a target rotation position of the speed- change motor 110 is over a fixed value to require a sudden speed change.