Patent ID: 11891781
Assignee: HITACHI CONSTRUCTION MACHINERY CO., LTD.
Field: Civil engineering (Other fields)
Classification: CPC E  F  B | IPC E  F

Claim 0:
1. A loading vehicle comprising:
a vehicle body including a plurality of wheels;
an engine mounted on the vehicle body;
a variable displacement traveling hydraulic pump that is driven by the engine;
a traveling hydraulic motor that is connected to the traveling hydraulic pump through a closed circuit and transmits drive force of the engine to the plurality of wheels;
a working device that is mounted rotatably in a vertical direction with respect to the vehicle body;
a loading hydraulic pump that is driven by the engine and supplies hydraulic oil to the working device; and a discharge pressure sensor that detects discharge pressure of the loading hydraulic pump,
wherein the loading vehicle further comprises:
a controller configured to control input torque of the traveling hydraulic pump; and
a solenoid proportional valve configured to generate control pressure for controlling displacement volume of the traveling hydraulic pump based on a control signal output from the controller, and wherein the controller is configured to:
calculate the displacement volume of the traveling hydraulic pump based on the discharge pressure of the loading hydraulic pump detected by the discharge pressure sensor so that maximum input torque of the traveling hydraulic pump decreases as the discharge pressure of the loading hydraulic pump or the input torque of the loading hydraulic pump increases; and
output a control signal corresponding to the calculated displacement volume to the solenoid proportional valve.