Abstract: A resettable thermal switch utilizing the principle that the permeability of a ferromagnetic material is sensitive to temperature variations in the vicinity of the Curie temperature. The resettable ferromagnetic thermal switch includes a resilient arm having a ferromagnetic aspect associated therewith (inherently or by attachment), an electrical contact including a stationary contact component and a movable contact component located at a distal location of the resilient arm, and a magnet located on one side of the resilient arm. The resilient arm has a predetermined inherent spring force urging the movable contact component toward or away from the stationary contact component depending on whether the electrical contact is to be spring biased closed or spring biased open, respectively. The magnet is located to provide a magnetic attraction force with the temperature dependent permeability of the ferromagnetic aspect in opposition to the inherent spring force.
Abstract: An apparatus and method for actuating and deactuating an electro-mechanical switch utilizing an energy-storing actuator is disclosed. An electro-mechanical switch can be configured to include an (internal or external) lever. A first magnet having a first magnetic field thereof is generally located on the (internal or external) lever of the electro-mechanical switch. A second magnet having a second magnetic field thereof is generally located on an energy-storing actuator, such as a bi-metal coil, wherein the second magnetic field of the second magnet opposes the first magnetic field of the first magnet to form an opposing magnetic force thereof in order to actuate and deactuate the electro-mechanical switch.
Abstract: A circuit breaker (10) has a current carrying bimetallic element (18) which bends upon self-heating and upon being subjected to a selected overload current transfers motion to a connecting plate (32) which displaces a latch surface (42b) from a catch (34a) of a bell crank mechanism (34) allowing a spring biased operating member (28) to move movable contact means (12) out of contact engagement with stationary contact means (14) thereby tripping the circuit breaker. An arc sensing circuit (52) is coupled to the load circuit and upon sensing selected arcs causes an arc responsive actuator (56, 62) to be energized to transfer motion to the latch (42) to trip the circuit breaker.
Abstract: A thermostat for regulating the temperature of a space includes: means movable in the thermostat for sensing the temperature of the space; a switch device having means for switching between a pair of switching positions; and a pair of permanent magnet means for magnetic coupling relation with the switching means. Means is provided for translating the temperature sensing movement of the sensing means to the magnet means pair so as to attract the switching means from one of its switching positions to the other thereof.
Abstract: A control unit for an electric motor in a vacuum cleaner which stops the motor when the motor temperature exceeds a certain level. The control unit is utilized with a vacuum cleaner having a low voltage circuit for controlling the motor speed and is simple and inexpensive, as well as safe in operation.