COMPONENT OPERATION / Travel Device Travel Mode Selection Valve The travel speed mode changes as the displacement angle of swash plate (3) is changed by tilt piston (5). Slow Speed (Maximum Displacement Angle) 1. Spool (8) in travel mode selection valve (1) is held in neutral by the spring (2) force. 2. As pressure oil from the control valve is blocked by spool (8) through the counterbalance valve. The circuit to tilt pistons (5) is opened to the hy- draulic oil tank. 3. Therefore, as the displacement angle of swash plate (3) is fixed to the larger side, the plunger (6) stroke becomes maximum.
As amount of oil re- quired to rotate the travel motor becomes maxi- mum, the travel motor rotates at low speed. (Refer to the Control System group/SYSTEM as for the control circuit.) To Hydraulic Oil Tnak Valve T1J1-03-05-007 1 - Travel Mode Selection Valve 3 - Swash Plate 5 - Tilt Piston 7 - Pilot Pressure (From So- lenoid Valve Unit (SI)) 2 - Spring 4 - Ball 6 - Plunger 8 - Spool T3-5-10 1 8 7 2 5 6 4 3 5 4 Counterbalance 3 Valve From Control