Abstract: Members to be coupled have hollow coupling parts at opposite side surfaces, a coupling member has, at opposite ends, press-fitting parts which are press-fitted in the hollow coupling parts, and angle shape concavities and convexities having crests which are corrupted upon press-fitting are formed on at least either one of an inner peripheral surface of the hollow coupling part and an outer peripheral surface of the press-fitting part. When the opposite end parts of the coupling members are press-fitted in the hollow coupling parts of the members to be coupled, the crests of concave parts of the angle shape concavities and convexities are corrupted by the opposed surface so as to be made into close contact with and firmly coupled to the associated surface, thereby it is possible to surely couple a pair of members to be coupled with a simple work.

Abstract: A rectangular cloth fixing frame for use in painting or embroidery. The frame including a plurality of frame portions. Each frame portion including a surface projection near an outer periphery of a front surface thereof and a fixing fitting groove on the outer peripheral end surface. Corner members connect the frame portions so as to form the cloth fixing frame. A cloth such as a canvas of a desired shape is spread over the rectangular frame, a plurality of fixing elements are driven through the canvas and into the fixing fitting groove to thereby fix the canvas to the rectangular frame under tension.