US2819570A - Safety device for grinding machines - Google ...
US2819570A US633454A US63345457A US2819570A US 2819570 A US2819570 A US 2819570A US 633454 A US633454 A US 633454A US 63345457 A US63345457 A US 63345457A US 2819570 A US2819570 A US 2819570A Authority US United States Prior art keywords grinding safety shield abrasive ring segment Prior art date Legal status …