Abstract: A racket frame, which has a frame main body 12 made of a fiber reinforced plastic, an ionomer film 13 covering the frame main body 12, and a coating film 15 formed over the ionomer film 13, is provided with a gas permeable porous material film 14 interposed between the ionomer film 13 and the coating film 15 so as to reduce voids inside the frame main body 12 and between the frame main body 12 and the ionomer film 13. Since voids are reduced inside the frame main body 12 and between the frame main body 12 and the ionomer film 13, and since the ionomer film 13 is reinforced with the gas permeable porous material film 14, the racket frame has an excellent mechanical strength. Adhesion between the frame main body 12 and the ionomer film 13 is excellent. Adhesion between the gas permeable porous material film 14 and the coating film 15 is good.

Abstract: A motor using Hall effect elements is disclosed, in which a disk-shaped multi-pole magnet which is circumferentially divided into a plurality of magnetic poles each magnetized in an opposite polarity to its adjacent magnetic poles is attached to a rotary shaft and a magnetic circuit is constituted by the multi-pole magnet and a yoke plate disposed to face the multi-pole magnet. A pair of Hall effect elements are disposed within a magnetic field of the multi-pole magnet to detect positions of the respective magnetic poles of the multi-pole magnet. Output voltages from the pair of Hall effect elements are supplied to a pair of drive coils, respectively, to generate driving magnetic fluxes therein. A pair of pole pieces are mounted on the yoke plate to face the pair of Hall effect elements, respectively.