Abstract: An electromechanical programmer having a user push-push reset action on the shaft of a rotary cam drum for actuating plural appliance function switches. Successive user push movements alternately latch and release the shaft between first and second axial positions. In the first axial position the shaft moves an auxiliary cam to close a line power switch for energizing a motorized cam drum advance and powering the program switches; and, the shaft is free-rotating with respect to the cam drum. In the second axial position the shaft moves an auxiliary cam to open the line power switch; and, the shaft is clutched to the drum to enable user rotation of the drum for appliance program interval selection.

Abstract: A electrical programmer (10, 120) is provided that features a first gear (18) that is rotated at a uniform rate by a drive source (16) and operative to rotate a driven gear (30) and an intermediate member (20) which, in turn, respectively operate to rotate a second cam (38) uniformally and a first cam (52) intermittently to open and close a first switch as a function of its uniform rotation; and, cam (52) is operative to open and close a second switch as a function of its intermittent rotation. Programmer (10, 120) preferably includes a rotary drum (110) operable to engage a plurality of electrical contacts in conjunction with the operation of the first and second sub-interval switches.

Abstract: A switch assembly to provide snap action switching on a cam rise in a program timer includes a follower assembly on the free end of a first blade to engage the program member to reference the first blade relative to the program member. A cam follower for actuating a second blade has a relatively high coefficient of friction between it and the follower assembly so that when a steep cam rise is encountered the horizontal force from the cam rise forces the cam follower tightly against the follower assembly, to lock the cam follower to the follower assembly. At the end of the cam rise, the horizontal force is released and the snap action occurs.

Abstract: A program timer wherein a single three blade switch assembly is utilized for both the line switching function and a cam track operated switch.

Abstract: The timing cam is advanced for switching purposes by the large reciprocating pawl acting on the ratchet teeth molded on the timing cam. When the program requires a timed period during which conditions remain the same the ratchet teeth are spaced so the pawl cannot pick up the next tooth until the cam is advanced by the small pawl acting on the separate ratchet provided with small, closely spaced teeth. This ratchet has a pinion gear driving the ring gear molded inside the timing cam. The steps imparted to the timing cam by the small pawl and ratchet are very small and consume appreciable time--the length of time taken to position the next tooth for engagement by the large pawl being determined by the space between the large teeth.

Abstract: The timer has switches including upper and lower passive blades and an active blade therebetween. The distal end of the lower passive blade has depending spacers which straddle the cam upon which the follower on the distal end of the active blade rides. The spacers reference the lower passive blade off the hub of the drum type program cam. The lower passive blade is provided with a rest or stop for the upper passive blade limiting downward movement of that blade. With precision molding, both passive blades are accurately referenced from the cam hub and the location of the follower which actuates the active blade is precisely located. Accuracy of switching is increased without increased precision in manufacture. Use of two cam tracks permits simultaneous actuation of the active and "passive" blades to effect faster switching. It is possible to provide a "make-make" arrangement instead of the double throw arrangement.