Abstract: An electrical switch contact arrangement having a spring which snaps the movable arcing contact away from the stationary arcing contact at a high rate of speed to open the arcing contacts, but only after the movable main contact has moved through a considerable portion, for example, at least about 50%, of its opening movement away from the stationary main contact. The spring is tensioned as the main contacts open. At an intermediate point during the opening movement of the movable main contact, the moveable main contact positively initiates opening movement of the arcing contacts whereupon the spring snaps the arcing contacts open at a high rate of speed independent of the opening speed of the main contacts.

Abstract: A manual operator for opening and closing an electrical switch, including a switch-driving element, a relatively rotatable handle element, and a resilient transmission, e.g., a leaf spring or springs, extending between the two elements. An abutment is fixed to one of the elements and a follower is fixed to the other, the abutment engaging the follower only after the resilient transmission has been tensioned by rotation of the handle element. When the driving element engages a portion of the switch mechanism, initial rotation of the handle causes the resilient transmission to be tensioned and the abutment to engage the follower. Further rotation of the handle is transmitted through the abutment and follower to the driving element to initiate the movement of the switch mechanism, following which the tensioned resilient transmission instantly shifts the switch mechanism through the remainder of its movement to snap the switch open or closed.

Abstract: Dead-bolt locking apparatus includes a door-carried dead-bolt mechanism having oppositely projecting dead-bolts on dual aligned slides, and a key-controlled cam-lock unit receivable in a cavity in the dead-bolt mechanism. The cam-lock unit is inserted into the cavity with the lock of the cam-lock unit "unlocked", developing balanced outward thrust on the door-securing dead-bolt slides. Locking the cylinder lock then secures the cam-lock unit against removal and thereby locks the dead-bolt apparatus.

Abstract: A switch for interrupting electric power to the customer of a utility, the switch including two female contacts for accepting the male plug-in contacts of a watt-hour meter, and two male contacts for insertion into the female contacts which ordinarily receive the male contacts of the meter. A switch is located between one of each female contact and its corresponding male contact, and an operator, such as a solenoid, opens the switch(es) in response to a signal, so as to disconnect the customer's load from the utility source. A latch holds the switch(es) open until another signal causes a second operator, such as a solenoid, to deactivate the latch and permit the switch(es) to reclose. An auxiliary switch in the circuits for energizing the two solenoids deenergizes the first solenoid when the switch(es) are latched open, and deenergizes the second solenoid when the switch(es) become unlatched and move toward their closed condition.