Screw-fitting clip and object-engaging mechanism using the same

An object engaging mechanism comprising a screw-fitting clip and a tapping screw to which said screw-fitting clip is to be fitted, wherein:

• said screw-fitting clip comprises a plurality of elastic engaging claws protruding radially from an edge of a center hole of an annular disk at an inclined angle relative to a surface of said annular disk, a plurality of protruding pieces arranged on an outer peripheral portion of said annular disk and extending away from said annular disk on a same side as said elastic engaging claws, and a plurality of claw pieces arranged on said annular disk and extending away from said annular disk on an opposite side as said elastic engaging claws and said protruding pieces;
• said tapping screw comprises a plurality of ridges and has a thread profile such that a first side of said ridges facing a shank end of said tapping screw is an outwardly convex curved flank, and a second side of said ridges is a gently inwardly concave curved flank;
• said elastic engaging claws of said screw-fitting clip have tips which are formed with bent end portions corresponding to said thread profile of said tapping screw;
• and
• said screw-fitting clip and said tapping screw engage an object therebetween by a forcible pushing operation whereby said shank end of said tapping screw is inserted through said center hole of said annular disk of said screw-fitting clip until a bearing surface of said annular disk reaches the object to be engaged, and said tips of said elastic engaging claws of said screw-fitting clip are fitted between said ridges of said tapping screw against a base portion of said inwardly concave curved flank of said ridges.