Considering that Joker lived in an abandoned version of the 1939 World's Fair's House of Tomorrow, complete with animatronic wife, I just assume Captain Clown was a forgotten General Motors prototype.

Also, the Bat-Computer was made out of Bakelite, according to Bruce Timm.

He wasn't living at the world's fair yet by this point in the series. I think that may have only been in one of the movies. When they introduced Harley the joker was living in an old fun house.

As for the bat computer, i don't think i ever saw that interview with Bruce Timm. Link?

The movie is supposed to take place before the series, so Joker might have taken Captain Clown with him when he ditched the World's Fair hideout.

He also took the robot wife. But he broke that one on his own.

i'm talking about the animated movies, not the tim burton films.

Robots are important because you can kill them, Batman wouldn't have done that to a human henchman.

He seemed pretty broken up about it, too.

Joker's tapping that Harley Quinn business. He doesn't need sexbots.

He seems more into Captain Clown than he ever was into Harley.

emphasis