GB1473292A - Clutch - Google Patents

Abstract

1473292 Positive clutches; clutch control; couplings UNITED GAS INDUSTRIES Ltd 3 June 1974 [20 June 1973] 29331/73 Headings F2C F2L and F2U In a clutch arrangement an output shaft 11 is rigidly coupled to an input member 18 or to a composite gear 22 depending on the axial position of member 18, which member disconnects the rigid drive between gear 22 and shaft 11 when coupled to shaft 11. A coupling collar 16 is axially movable on shaft 11 and fixed for rotation with it by a pin 15 which passes through notches 14 in collar 16 and through a hole 17 in shaft 11, this collar having teeth engaged by teeth on member 18 when member 18 is moved in a direction A<SP>1</SP>. A leaf spring 24 biases gear 22, loosely mounted on shaft 11, to the left as shown via a coupling disc 23 to engage facial teeth 27 on gear 22 with pin 15 and rigidly connect gear 22 and shaft 11. The gear 22 is disengaged from pin 15 when member 18 moves in direction A<SP>1</SP> to engage collar 14 and move this to move gear 22 axially against spring 24. A spiral spring 29 interconnects coupling disc 23 and shaft 11, the friction coupling between disc 23 and gear 22 slipping when member 18 is engaged with collar 16 and if gear 22 is braked (by means not shown). As described the clutch is included in a timing device with member 18 driven by an electric motor through a gear 20, an output gear 12 on shaft 11 connected to timing gears of such as a time switch and gear 26 connected to an escapement. With member 18 engaging collar 16 and pin 15 disengaged from teeth 27 the escapement which is part of a reserve spring drive may intermittently release and hold gear 22, which gear can rotate faster than shaft 11 when released due to the unwinding of spring 29. The member 18 may be moved in directions A and A<SP>1</SP> by a solenoid.