Hamilton Manfg. Co. v. Poll.

The bill was filed to enjoin infringement of patent and for other relief. Plaintiff had decree. Defendants have appealed.

The contest was narrowed at the hearing to alleged infringement of claims to an automatic steering device on a planting machine manufactured and sold by plaintiff on which plaintiff has patent No. 1,723,-073. It is thus claimed:

“A frame having a swivel yoke and a caster wheel in said yoke, a guide wheel pivotally connected to said yoke and positioned ahead of said caster wheel and adapted to travel in a guide furrow. ’ ’

Defendants also make and sell planting machines on…