Abstract: A torque limiting drive and programmer/timer using same. A motor drives a driving member which has drive lugs engaging the central web of a plural-armed wave spring. The wave spring arms frictionally engaged radially oppositely facing annular friction surfaces on a driven member, which in a programmer/timer is the program cam, which upon rotation of the cam is operative for sequentially actuating electrical switches. User rotation of the cam when the motor is not operative allows the wave spring arms to slip against the annular friction surfaces permitting the user to position the cam as desired.

Abstract: A programmer for an appliance having a single timing motor drive for a rotating cam drum which actuates plural appliance program function switches. An advance pawl drives the cam drum in one direction when selectively engaged with a toothed wheel on the drum and drives through a first rotary frictional coupling. A gear train drives continuously through a second rotary frictional coupling and drives the cam drum in a reverse direction when the advance pawl is disengaged. When the pawl is engaged, the second rotary frictional coupling slips and is overdriven in a direction opposite its driving direction by said first frictional coupling.

Abstract: A programmer/timer for an appliance of the type having a rotatable cam drum advanced for sequential actuation and deactuation of a plurality of electrical switches. The drum is advanced or indexed intermittently by an oscillating advance pawl engaging a ratchet wheel and also continuously by a gear driven by a common motor for oscillating the advance pawl. The ratchet wheel has a hub which is frictionally engaged to drive the cam drum. The driven gear in turn is frictionally engaged with the hub to also drive the ratchet wheel. When the advance pawl engages the ratchet wheel for intermittent drive, the driven gear slips on the ratchet hub. Upon user selection, a separate cam track lifts the advance pawl to permit the driven gear to continuously drive the ratchet wheel.

Abstract: A programmer/timer for an appliance of the type having a rotatable cam drum advanced for sequential actuation and deactuation of a plurality of electrical switches. The drum is advanced or indexed intermittently by an oscillating advance pawl engaging a ratchet wheel and also continuously by a gear driven by a common motor for oscillating the advance pawl. The ratchet wheel has a hub which is frictionally engaged to drive the cam drum. The driven gear in turn is frictionally engaged with the hub to also drive the ratchet wheel. When the advance pawl engages the ratchet wheel for intermittent drive, the driven gear slips on the ratchet hub. Upon user selection, a separate cam track lifts the advance pawl to permit the driven gear to continuously drive the ratchet wheel.

Abstract: A programmer/timer for an appliance of the type having a rotatable program cam advanced by an oscillating pawl engaging a ratchet wheel for actuating at least one appliance function switch. A shaft is provided for enabling user positioning of the cam after limited rotational lost-motion for selecting the program interval. An annular member having a conical cam surface is received over the shaft and is helically cammed to the shaft. During the limited lost-motion rotation of the shaft, the collar moves axially and the conical cam surface lifts the pawl from the ratchet thereafter enabling user rotation of the program cam for positioning same for program interval selection.