Abstract: A vertical spindle duplex head for a grinder includes an annular pressure wheel and a receiver wheel arranged to rotate and revolve workpieces between the annular surfaces of the pressure wheel and the receiver wheel and a grindstone for one end portion of the workpieces driven in the opposite directions of rotation of the pressure wheel and receiver wheel and at their different rotational ratios. The workpieces rotate and revolve between these wheels, thereby grinding their end face by means of a grindstone arranged around the external periphery of a rotary carrier.

Abstract: A device for preventing creep of the outer ring of an antifriction bearing relative to the housing supporting the outer ring. The bearing outer ring has a circumferential groove formed in its outer periphery eccentrically thereof and having fitted therein a bandlike resilient ring which has a curved protruding portion larger than the depth of the groove. In the vicinity of the protruding portion, the resilient ring has its opposite end portions lapped over each other within the groove. When the outer ring acts to creep within the housing, the shallow groove portion of the groove approaches the protruding portion and lapped end portions of the ring, causing the end portions to act as a wedge between the housing and the outer ring to stop the creep.