| 摘要 |
PROBLEM TO BE SOLVED: To excellently operate both operation objects when operating both fork and mast simultaneously.SOLUTION: A flow rate control valve 34 is arranged between a hydraulic pump motor 30 and a lift descending proportional valve 32 to open and close a valve in accordance with a pressure difference between a pressure P1 between a lift cylinder 14 and a lift descending proportional valve 32 and a pressure P2 between the hydraulic pump motor 30 and the lift descending proportional valve 32, and a flow rate control valve 34 controls a flow rate to the hydraulic pump motor 30 side of the hydraulic oil exhausted from the lift cylinder 14 and a flow rate to a drain (oil tank T) side in response to a difference between a required revolution number of the hydraulic pump motor 30, which is required for performing a descending movement at an instructed speed in response to an operation quantity of a lift lever 22, and an actual revolution number of the hydraulic pump motor 30. |
