Abstract: An overload/open-phase tripping device for a circuit breaker includes a plurality of bimetallic elements arranged in a row; a differential shifter mechanism; and a tripping lever for transmitting a force applied by the differential shifter mechanism to a switching mechanism. The differential shifter mechanism includes a push shifter having a plurality of operation ends; a pull shifter having a plurality of operation ends; and a differential lever disposed between the push shifter and the pull shifter. The differential lever is provided with an action end for applying the force to the tripping lever upon an overload, and an action end for applying the force to the tripping lever upon an open-phase. The two action ends face the tripping lever, and the action end for the open-phase is located at a position farther from the tripping lever than the action end for the overload.

Abstract: A surge suppressing device includes a voltage-dependent resistor having an opening formed therethrough. A pair of preformed pads formed of an electrically conductive material is located adjacent a first and second side respectively of the voltage-dependent resistor proximate the opening. The electrically conductive material flows through the opening creating an electrical short between the first and second sides when the voltage-dependent resistor is heated in response to excessive leakage current flowing therethrough.

Abstract: A thermal cycling switch has an insulated housing carrying a centrally located rotating cam. The cam operates a first ON/OFF switch connectable between a pair of contacts that are connected to one side of a load and one power line. The rotary cam also moves an adjusted contact mounted on an adjustable arm which cooperates with a cyling arm contact to operate as another switch between the other side of the load and another power line. The cycling arm includes a bimetal member which is electrically insulated at the base, as well as a current conducting strip formed of pure nickel metal extending along the low expansion side of the bimetal member.

Abstract: There is disclosed a circuit breaker overcurrent tripping device. This tripping device includes: a fixed iron core accommodating a bimetallic strip in which a flow of an electric current is present, the bimetallic strip bending when an overcurrent is present; a movable iron core attracted to the fixed iron core when the electric current becomes a short circuit accident current; a tripping mechanism operated both by the movement of the movable iron core or the bending of the bimetallic strip; a fixed contact point connected via a connecting wire to a load terminal; a movable contact point fixed to the movable iron core and connected via a conductor wire to a fixed end of the bimetallic strip; and a flexible conductor for connecting a free end of the bimetallic strip to the load terminal. In this configuration, the fixed iron core is wound with at least one turn of the flexible conductor, thereby increasing the magnetic force attracting the movable iron core to the fixed iron core.

Abstract: A circuit breaker is provided of the push-pull type for use in the cockpit of an aircraft wherein the plunger of the circuit breaker is illuminated upon the opening of a circuit. The illumination immediately attracts the pilot's attention so that corrective action can be taken. A bi-metallic strip bows when it is heated due to overloading of the circuit causing the plunger to be extended and to complete a secondary circuit to a light located within the head of the plunger. A number of the circuit breakers are electrically interconnected to provide a visual indication to the pilot that a fault condition has occurred in one of the monitored aircraft circuits. In addition, an indicator is available to inform the pilot that a second fault condition has occurred subsequent to the occurrence of a first fault condition while the first fault condition remains.

Abstract: A thermal relay having main contacts and normally closed auxiliary contacts, a thermally responsive actuator for sequentially operating the main and normally closed auxiliary contacts, and an electric heater for causing said thermally responsive actuator to move. The power supplied to the electric heater is controlled by the auxiliary contacts so that the position of the thermally responsive actuator in the operated position is self-regulated. Because the position of the thermally responsive actuator in the operated position is self-regulated, the time for deactuation of the relay is reduced from prior art relays. One use of the relay of the invention is that of a cornering relay in an automobile signal light system whereby the relay is actuated by the signal light flasher to actuate a cornering lamp.

Abstract: The invention relates to a timing pulse generating switch assembly, particularly for the monitoring circuit of an oil or gas furnace, having at least one snap switch provided with a contact arm which carries the movable contact. The movable contact arm is fixed with respect to the housing at one end and there is provided a snap system which adjusts the contact arm. The snap system possesses a snap arm which is fixed with respect to the housing at one end and is preferably formed by the contact arm. The snap system includes a snap spring which is articulated to the snap arm and, at its other end, is articulated to a slide that is reciprocatable by a bimetallic member. The switch assembly includes and is influenced by a locking element that is actuated by separate means such as the armature of a relay. The locking element functions to block the movable contact in its rest position as well as in its operating position by using a blocking member which is carried along by the slide.