Apparatus and method for controlling angular relation between two rotating shafts

A method of replacing a pair of timing gears on a pair of parallel shafts for rotating said shafts in a precise timed relation to each other;

• said method comprising the following steps;
• removing the timing gears from said shafts;
• mounting a first replacement timing gear on a first shaft in fixed relation thereon;
• providing a second replacement timing gear for the second shaft, the second replacement timing gear having a pair of concentric inner and outer timing gear portions;
• providing cooperating members on the outer periphery of said inner gear portion and on the inner periphery of said outer gear portion for interfitting to permit relative longitudinal movement between said gear portions and to provide a rotational drive connection between said gear portions;
• mounting said inner concentric gear portion on said second shaft in fixed relation thereon;
• fixing said first shaft and timing gear thereon against rotation;
• rotating said second shaft and inner concentric gear portion thereon to a precise angular relation relative to the fixed position of said first shaft,
• then fixing said second shaft against rotation;
• and
• then moving said outer gear portion longitudinally onto said concentric inner gear portion for interfitting of said cooperating members on said gear portions and for engaging said first timing gear in a rotational force transmitting relation.