| 摘要 |
PURPOSE:To improve an oil feed function and durability of a pump. by a method wherein a solenoid valve which is opened and closed by a signal from a float switch arranged to each oil path is provided to each oil discharge piping and besides, a common solenoid which opens a by-pass between an oil tank and oil discharge pump when all of those solenoid valves are closed, is also provided thereto. CONSTITUTION:When a quantity of oil in each oil paths 51-56 becomes not more than a minimum allowable valve, a signal is emitted by the detection with a float switch 64, and a solenoid valve 65 is closed by this signal. Therefore, oil discharge is temporarily stopped and the level of oil rises. Then, when the quantity of oil reaches a maximum allowable level, a signal is emitted by the detection with the float switch 64, and the solenoid valve 65 is opened by this signal to start again oil discharge. Thus, each oil path maintains a predetermined oil face level. Further, when waste oil is not circulated to an oil discharge pump 63 from the oil paths 51-56 because all the solenoid valves 65 are closed, a common solenoid valve 67 is opened by an electric signal. Then, the oil discharge pump 63 is interconnected with an oil tank 30 through a by-pass 66, and the oil circulates through the by-pass circuit via the oil discharge pump 63. |
