Patent ID: 7036572

Claim:
An oil cooler structure of an automatic transmission comprising: an upper tube elate and a lower tube plate together forming an oil circulation space defining oil holes at a top and a bottom: an oil passage defined by an upper tube plate plane part and a lower tube plate plane part, said oil passage communicating with said oil circulation space intermediate of said top and bottom oil holes and extending longitudinally for a first distance; and an upper tube plate reinforcement and a lower tube plate reinforcement each arranged in a layer in said oil passage formed between the plane part of the upper tube plate and the plane part of the lower tube plate and extending away from the upper and lower tube plates for a second distance less than the first distance, said plane parts respectively welded to said upper tube plate reinforcement and said lower tube plate reinforcement and embossed parts thereof protruding toward the center of said oil passage being mutually abutted and welded together.