摘要 |
This invention relates to a reduction mechanism including two gear trains, of different speed reductions, for rotating one cam, both gear trains having different input gears but a same output gear, said input gears being rotatable by a step-up gear mounted on a pivotable lever and rotatable by a driving pinion coupled to a motor, a second pivotable lever having followers responsive to ramp means provided on said cam for suddenly pivoting said first lever through a spring linked to said two levers and thus moving said step-up gear into engagement with the input gear of one or the other of said two gear trains. |