Beam was a manufacutuer that produced certain washing machine parts such as a transmission, fluid drive clutch, pump, etc. Then they sold these parts to other manufacturers who put together their own washers. Most of the manufactuers desiged their own tubs, agitators, and control panels but it was all Beam componets below.
The most famous of all brands to be of a Beam design was Speed Queen. But the very first Beam machine was the 1947 AMC Coronado, others included Hotpoint (until 1956), Easy, One Minute, Firestone. There are others I just can't think of them right now.
Any vintage Solenoid Speed Queen washer is a Beam machine.