Standard Stoker Co. v. Berkley Mach. Works & Foundry Co.

SOPER, Circuit Judge.

This appeal involved four patents relating to automatic stokers for coal-burning railroad locomotives. Plaintiff, who is the largest manufacturer of such stokers, has marketed two types, conveniently termed type A and type B. The general principles of both types of stokers are quite old and beyond the protection of any patents. The four patents in question are for specific parts in the construction of these stokers and for such specific parts in combination with other parts, as hereinafter explained.

The type A stoker consists of a horizontal conveyor screw, running in a…