| 摘要 |
PROBLEM TO BE SOLVED: To provide a construction tool driving hydraulic apparatus capable of protecting a hydraulic actuator and respective apparatus parts.SOLUTION: In a construction tool driving hydraulic apparatus comprising a solenoid direction changeover valve 16 which changes a supply direction of working oil to a hydraulic motor 11 among clockwise turning, counterclockwise turning, and stopping and a changeover switch 21 which changes power supply to solenoids 16R, 16L of the solenoid direction changeover valve among the clockwise turning, counterclockwise turning, and stopping, and a throttle 17b which restricts flowing of the working oil from the hydraulic motor, an electric circuit 14 between the changeover switch and solenoid direction changeover valve is provided with contacts 23R, 23L which turn off power supply circuits 22R, 22L for different turning directions when the changeover switch is set to the clockwise or counterclockwise turning, respectively, and also provided with an off delay timer 24R, 24L which hold the contacts in a broken state only for a previously set time when a setting of the changeover switch is reset.SELECTED DRAWING: Figure 1 |
