Grinding head for carrying a replaceable abrasive sheet

A grinding head for carrying replaceably an abrasive sheet and for detachable and driving connection to a portable rotary power unit, said head consisting of a flattened plate-shaped support member having a convex outer face and a concave inner face;

• a sheet of thin hardened padding secured to the outer face of said support member, and taking the form thereof, said padding sheet having substantially the same dimensions as said outer face of said support member;
• a shank having an inner end secured to and projecting centrally from the inner face of said support member;
• and having a screw-threaded inner end portion, and an outer end portion adapted to be detachably and drivingly connected to a portable rotary power unit;
• on said shank, a flattened plate-shaped clamping member of smaller diameter than that of said support member and having an inner concave face facing the inner face of said support member, an outer convex face, and a central hole through which said shank passes, the peripheral edge of said clamping member being clamped to the inner concave face of said support member;
• and a clamping nut on said screw-threaded portion of said shank;
• whereby marginal edge portions of an abrasive sheet applied to the outer face of said sheet of thin hardened padding, and overlapping the latter, can be folded between said support member and said clamping member and be clamped between same by tightening said nut.