Abstract: A manufacturing method and apparatus for gears for a speed change device. The gears having a large end and a small end forming a reverse-tapered tooth part on an outer circumference thereof, spline teeth of an intermediate material having the small end provided in a rim of the large end thereof, a plurality of dies having a radial shape and an inclination angle to a gear axial line and slidably holding to an inclined axial line on a holding member are slid from outside of the radiation direction toward the center by a pushing cam mechanism, thereby pushing the reverse-tapered blade part formed at the leading end of the die, the spline teeth are formed in the reverse-tapered tooth part, and the die is slid by an extracting mechanism from the center of the radiation direction toward the outside along the inclined axial line.

Abstract: [Problems] To present a manufacturing method of gears for a speed change device, capable of manufacturing gears for a speed change device by using a manufacturing apparatus, small in the load when forming, and small and simple in structure, and capable of obtaining gears for a speed change device not limited in gear deforming positions, small in generation of strain, and large in strength.

Abstract: A low cost computer is suitable for small size configuration. Casings 4 and 32 are formed by aluminum, which is a heat radiating material, and CPUs 6 and 36, hard disk devices 8 and 38, control ICs 40 and 42 and a memory IC are mounted on the casing 4 directly or by the heat radiating material. The casings 4 and 32 are utilized as heat radiators, thereby making the entire computer a smaller size.