To reconcile supporting of force of a direction perpendicular to a rotary shaft in a pivot bearing and assembling workability.
A part which is normally in contact with a pivot shaft 5 is made to have an inclined angle slightly larger than an inclined angle of the pivot shaft 5 to realize point contact with little frictional loss by supporting force of the direction perpendicular to the rotary shaft generated by engagement of a fifth wheel 12 and a rotor 3. A side close to an opening part of a pivot bearing 7 is made an inclined angle which is made much larger than an inclined angle of a conical surface, When assembling the pivot bearing 7, a method in which gears such as the rotor 3 and the fifth wheel 12 are inserted into a bottom plate 1 and a wheel train receptacle 2 is covered from the above is normally adopted. At this time, the rotor 3 becomes a slightly inclined state from the original rotary shaft by a gap between a tenon 6 and a noble stone bearing 8 of the rotor 3, but if the pivot shaft 5 is brought into contact with the conical surface of the pivot bearing 7 when the wheel train receptacle 2 is lowered from an upper side, the rotor 3 is subsequently guided according to the conical surface and reaches up to a top of a recess.
MINAMITANI TAKANORI
MACHIDA TADAYASU
TAKAHASHI SHIGEYUKI
MURAKAMI ATSUSHI
