Work Vehicle

Abstract

Provided is a work vehicle which is capable of appropriately setting the height of a work tool as a control threshold value for a ride control device or an automatic transmission control device, and which is excellent in operability, travel stability, and work efficiency. A value detected by an angle sensor ( 39 ) when a signal import switch ( 46 ) is operated by an operator is stored in a height position storage unit ( 35 b ) of a main controller ( 35 ) as height position information about a bucket ( 13 ) for excavation work. In the height position storage unit ( 35 b ), the height position of the bucket ( 13 ) for hauling work and the height position of the bucket ( 13 ) for loading work are stored in advance as offset values from the height position information about the bucket ( 13 ) for excavation work. In this way, the ride control device or the automatic transmission control device can be appropriately controlled regardless of the preference or habit of the operator.

1 . A work vehicle comprising: a work tool which is moved vertically within a predetermined movable range by driving of a lift cylinder; a sensor which detects a height position of the work tool; and a controller which serves to control driving of a control target; wherein:
 the controller includes a signal import unit which imports a detection signal of the sensor as a signal of an excavation position by manual operation of an operator, a height position storage unit in which a specific height position of the work tool is stored as an offset value from the excavation position as to the control of driving of the control target, and a signal generating unit which generates a control signal for the control target in accordance with a height position of the work tool obtained from the detection signal of the sensor as soon as the obtained height position reaches the height position of the work tool stored in the height position storage unit.   
     
     
         2 . A work vehicle according to  claim 1 , wherein:
 the control target includes a vibration suppression device by which circulation of hydraulic oil between the lift cylinder and a hydraulic pressure accumulator is changed over in accordance with a vehicle speed and the height position of the work tool.   
     
     
         3 . A work vehicle according to  claim 1 , wherein:
 the control target includes a transmission control device by which a speed stage of a transmission is changed over in accordance with a vehicle speed, an engine speed and the height position of the work tool.   
     
     
         4 . A work vehicle according to  claim 1 , wherein:
 the control target includes both a vibration suppression device by which opening/closing operation of a control valve provided in a hydraulic circuit connecting the lift cylinder and a hydraulic pressure accumulator is changed over in accordance with a vehicle speed and the height position of the work tool, and a transmission control device by which a speed stage of a transmission is shifted in accordance with the vehicle speed, an engine speed and the height position of the work tool.