Abstract: An improvement of a homopole type AC generator which is of homopole type arrangement and is adapted to generate alternating current (AC) depending upon interlinkaging operation of magnetic fluxed comprising a rotor magnet rotatable by a roational force from outside, a yoke through which magnetic fluxes flow from the N pole of the rotor magnet to the S pole and forms a part of a magnetic circuit, and generating coils provided at positions interlinking with the magnetic cirucit, wherein a magnetic circuit connecting two rotary pole pieces which are provided on a rotary drive shaft at both sides of the rotor magnet is disconnected to eliminate a harmful magnetic circuit opposing the action of generation.

Abstract: Spur gears of which the engagement is made noiselessly because of three adjustment functions wherein the central errors of the gears as rotary bodies are compensated by specific method of freeing the wheel center of a gear in a train of gears. The foundation parts (rim parts) of the gear teeth are subjected to qualitative treatment so as to have a large elasticity against maximum bending. The moment of forces working on said teeth are made to have a ring shape and the gears are arranged to have a large backlash. The holding mechanism is constructed so that the rotational center of the ring-shaped gears may be slightly movable in relation with the rotation center of the gear shaft. Backlash due to excessive vibration of the wheel center is prevented by providing a P.C.D.