The oil temperature control unit null in the hydraulic

摘要

PURPOSE: To improve workability just after start by shortening warm-up time when starting a hydraulic equipment or the like. ;CONSTITUTION: An oil cooler 4 is connected to the downstream part of a hydraulic circuit, and a bypass oil duct 6 is provided at the oil cooler 4. An electromagnetic opening/closing valve 7 is arranged at the bypass oil duct 6, and a temperature sensor 9 is provided at an oil duct 8 toward the oil cooler 4. Then, the temperature sensor 9 is connected to the electromagnetic opening/closing valve 7 through a control part 10. Thus, when the oil temperature calculated based on the value detected by the temperature sensor 9 is low in the case of starting the hydraulic equipment or the like, hydraulic oil does not flow into the oil cooler 4 by opening the electromagnetic opening/closing valve 7, so that the oil temperature of hydraulic oil can be speedily raised and the warm-up time can be shortened.;COPYRIGHT: (C)1995,JPO