To limit rise of temperature of a control unit controlling an automatic transmission and incorporated in it up to the predetermined temperature.
This control unit cooling device is provided with an upper part housing 40 formed to hold a control valve 30 from above and let cooling lubricating oil flow, a lower part housing 50 holding the control valve 30 from a lower part, provided with the control unit 100 provided with electronic parts 101 on it in the lower part, and having a passage 60 for letting the cooling lubricating oil in the upper part housing 40 pass through a clearance between the control valves 30, and a large unit arranged space 61 formed to let the cooling lubricating oil passing through the passage 60 flow onto an upper face of the control unit 100. Potential energy of the cooling lubricating oil is ensured and applied onto the upper face of the control unit 100 so that the cooling lubricating oil flows in the unit arranged space 61 to achieve efficient cooling.
IWATA AKIHITO
NODA KAZUYUKI
KAWAMURA TATSUYA
TOYOTA MOTOR CORP