Abstract: A housing includes a pan shaped front cover having a front open wall with a rectangular peripheral flange formed around the front wall and a pan shaped rear cover having a closed end and an open end to connect with the rectangular flange. A plurality of engaging members are formed on the peripheral flange. A pair of elongated plates spaced parallel and apart from one another having a length equal to the length between the front and rear cover. Each of the elongated plates have a front end with an engaging member and a rear end with another engaging member. An elongated recessed groove facing into the interior of the housing extends from the front end to the rear end. An auxiliary plate extends inclinedly from the intermediate of the elongated plate toward the front cover. The free end of the auxiliary plate has an engaging member. The rear ends of the elongated plates are connected by a transverse plate.

Abstract: A connector includes a pawl-like metal piece to be engaged with the axle or a rear wheel of a bicycle. The metal piece has two protrusions to be inserted in and connected to the joint ends of a plastic chain stay and a plastic seat stay, and a resin coated fabric material wrapped around each protrusion and each joint end. Spaced annular ridges are provided on the protrusions to engage with the resin coated fabric material. The fabric material is cohesively bonded to the corresponding plastic joint after application of heat.

Abstract: A looped racket frame has two frame portions which are symmetrically opposite with respect to the longitudinal axis of the frame to hold some transverse string lines passing through a central area of the string web. These opposite frame portions are provided with two elongated indentations at the inner peripheries thereof to enlarge the distance between the string holes which hold the transverse string lines, thereby lengthening the string lines passing through the central area.

Abstract: The cross section of the looped frame portion 20 of a racket varies with the changing thickness thereof as measured in a direction perpendicular to the plane of the looped frame portion. The looped frame portion has a first and a second portion 21, 22 divided by the longitudinal axis of the racket. The first portion 21 has the smallest cross-section at first point A2 adjacent to an uppermost point of the frame opposite to the throat of the racket and the largest cross-section at second point B2 adjacent to the throat. The second portion 22 has the largest cross-section at a point A1 which is symmetrically positioned on the racket frame with the point A2 of the smallest cross-section of the first portion 21 and the smallest cross-section at another point B1 which is symmetrically positioned on the racket frame with the point B2 of the largest cross-section of the first portion.

Abstract: A badminton racket frame comprising a ring frame, a throat, a shaft and a grip wherein said parts of the racket frame further comprising a layer made of carbon fiber reinforced plastics or fiber reinforced plastics having been soaked in a high polymer epoxy resin to form a prepreg sheet, and a solid independent foaming material as the core thereof. The present badminton racket frame is hot-pressing molded and has a shaft with the foaming material core therein having a diameter around one millimeter.

Abstract: This invention discloses an improved method of producing fiber glass or fiber graphite reinforced racket frames in which a shell made of a plurality of layers of resin-impregnated oriented graphite fibers is squeezed during the heating period to contact completely with the inner surface of a mold cavity by means of two interior pressure separately generated by compressed air and a foamable elastomer or rubber composition wrapped within the shell.