Abstract: A bi-stable clutch is introduced comprising an input and output shaft, a hub assembly attached to output shaft, a hub assembly attached to output shaft and operatively associated with a friction ring which rotates with output shaft of the unique bi-stable clutch. The input shaft is connected to a rotor which drives an armature plate to which the rotor is rotatably attached. The rotor and armature plate are forced apart when the clutch is engaged creating an air gap between the two large enough to not be overcome by the permanent magnet field attracting the armature plate due to a force caused by compression coil springs and the armature plate remains in contact with the rotor and the clutch remains engaged without continuous current transmitting torque from the input to the output shaft.

Abstract: Apparatus for selectively enabling and disabling a process depending on the instantaneous value of a measurement made during the process in accordance with a predetermined program recorded by shading adjacent segments on an area of a record means the length of which is an analog of the total range of the measurement with each of the segments representing an interval of the measurement during which the process is to be enabled or disabled. A plurality of memory cores in one to one correspondence with subsegments of the measurement range analog are caused during programming to occupy one of two bistable states in response to a light sensor responsive to the light originating from an incident source and reflected by the program record. After programming, the memory cores are interrogated in accordance with the instantaneous value of measurement and a process control switch is set to a state corresponding to the state of the last interrogated memory core.