| 摘要 |
PROBLEM TO BE SOLVED: To identify a factor of failure of an oil cooling system in a transmission.SOLUTION: Failure of pipes P1, P2 is determined when a hydraulic pressure P is more than a second hydraulic pressure threshold value PS2, and an oil temperature T is higher than an oil temperature threshold value TS; failure of a hydraulic circuit of a transmission M is determined when the hydraulic pressure P is more than the second hydraulic pressure threshold value PS2, and the oil temperature T is the oil temperature threshold value TS or lower; failure of an oil cooler OC is determined when the hydraulic pressure P is a first hydraulic pressure threshold value PS1 or more, and is the second hydraulic pressure threshold value PS2 or less, and the oil temperature T is higher than the oil temperature threshold value TS; failure of the hydraulic circuit of the transmission M is determined, when the hydraulic pressure P is less than the first hydraulic pressure threshold value PS1, and the oil temperature T is higher than the oil temperature threshold value TS; and impossibility of failure determination of the oil cooling system is determined when the hydraulic pressure P is less than the first hydraulic pressure threshold value PS1 and the oil temperature T is the oil temperature threshold value TS or less. Thus, the factor of the failure of the oil cooling system can be determined while finely classifying the factors.SELECTED DRAWING: Figure 3 |
