US Patent 11529747 Back shaver

A back shaver includes a cutter head assembly and a handle. The handle is connected to the cutter head assembly. The cutter head assembly includes cutter heads, a cutter head frame, and a connecting member. The cutter heads are embedded in a front surface of the cutter head frame. A back surface of the cutter head frame is connected to the connecting member through a rotating shaft. Elastic components are disposed on one side, distal from the handle, of the connecting member. Sliding blocks are disposed on the back surface of the cutter head frame. When the handle is operated, a first force moment is applied to the cutter head frame through the connecting member, and a free end of each of the elastic components slides along a first end of a corresponding one of the sliding blocks to a second end of the corresponding one of the sliding blocks.