Spring driven timer

Claim 1

In a spring driven timer which is manually settable to select a time interval: an upper inverted cup-shaped cover having means centrally therein securing it to the top of a vertically extending shaft; a base member having a housing cover member mounted thereon and defining a mechanism space above said base member and below said housing cover member; timer mechanism comprising spaced upper and lower frame plates supporting a timer gear train, the upper plate being mounted on said housing cover member and said lower plate being mounted on said base member; said shaft extending downwardly through and being journaled in said housing cover member and in said lower plate and having a lower terminal portion extending below said lower plate into a space within said base below said lower plate; a gear mounted corotatably on said shaft in limited spaced relation above said lower plate and coupled with said gear train; a main spring coiled about said shaft above said upper plate and anchored at one end to said shaft and at its opposite end to said housing cover member; a bell carried by said housing cover member outside of said mechanism space; means for sounding said bell in one rotary position of said shaft and including actuating cam structure carried by the lower terminal portion of said shaft below said lower plate and effecting releasable coupling with a bell striker and actuator mounted on said lower plate; and means for limiting rotation of said shaft to about 360* during manual setting of the timer by rotation of said shaft through said upper cover and including a first limit member corotatably secured to said shaft between said gear and said housing cover member and a second limit member comprising a plate mounted about said shaft below said lower plate and above said actuating cam structure, said second limit member having a stop lever projecting upwardly through an aperture in said lower plAte and being engageable by a stop dog on said first limit member, said aperture being of a width to limit movement of said lever in either rotary direction to about equal the angular extent of said dog plus twice the thickness of the lever whereby to permit the 360* rotation of the shaft.