Patent ID: 11926986
Assignee: KAWASAKI JUKOGYO KABUSHIKI KAISHA
Field: Civil engineering (Other fields)
Classification: CPC E  F | IPC E  F

Claim 5:
6. The hydraulic excavator drive system according to claim 1, comprising:
a boom operator;
an arm operator;
a bucket operator; and
control circuitry that controls the electric motor and the second switching valve, wherein
when the second switching valve is in an open position in which the second switching valve opens the relay line, an opening area of the second switching valve is changeable, and
when the second switching valve is in the open position,
if neither the arm operator nor the bucket operator is operated, the control circuitry controls the second switching valve to maximize the opening area of the second switching valve, and
if either one of the arm operator or the bucket operator is operated, the control circuitry controls the second switching valve such that the second switching valve functions as a restrictor.