| 摘要 |
PROBLEM TO BE SOLVED: To provide a hydraulic oil temperature estimation device which can estimate a temperature of hydraulic oil on the basis of a current for driving electric oil pumps.SOLUTION: A hydraulic oil temperature estimation device comprises: a load torque calculation part 13 which calculates load torque Tmop acting on electric oil pumps 11, 11a and 11b on the basis of a current Imop for driving the electric oil pumps 11, 11a and 11b whose rotation numbers and discharge amounts of hydraulic oil form linear shapes; a viscosity calculation part 14 which calculates the viscosity &ngr; of the hydraulic oil on the basis of the load torque Tmop; and an estimated oil temperature calculation part 16 which calculates an estimated oil temperature TEe of the hydraulic oil on the basis of the viscosity &ngr; of the hydraulic oil. Thereby, a temperature of the hydraulic oil can be easily estimated at a low cost on the basis of the current Imop for driving the electric oil pumps 11, 11a and 11b. |
