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: A method of fabricating and the structure of a micro-electromechanical switch (MEMS) device provided with self-aligned spacers or bumps is described. The spacers are designed to have an optimum size and to be positioned such that they act as a detent mechanism for the switch to minimize problems caused by stiction. The spacers are fabricated using standard semiconductor techniques typically used for the manufacture of CMOS devices. The present method of fabricating these spacers requires no added depositions, no extra lithography steps, and no additional etching.

Abstract: The invention relates to a reed contact unit (1) for electric switching functions, comprising a metallic contact blank (2) featuring a base (3) with at least one contact arm (5) configured integral with it, and comprising an electrically non-conducting frame part (7) accommodating fixedly the base (3) of the contact blank (2). To avoid deformations and damage to the contact arms (5) of the reed contact units (1) when used in bulk, at least one of the long sides (12) and the front end (9) of the contact arm (5) are surrounded by at least one frame shank (8) configured integral with the frame part (7), the front end (9) of the contact arms (5) being fixable releasably in the frame shank (8).

Abstract: A motor starting device for de-energizing the starting winding the required motor speed is reached comprising electromagnetic means (3) to urge actuation of the switching means (20,21) and a latch member (10) controlled by a thermal temperature-balanced bimetallic strip (5) to prevent switching until the bimetallic strip (5) reaches a selected temperature through current flow flow therethrough.

Abstract: The invention provides a magneto-thermal device for overcurrent relays.The end of a core, whose axial position may be adjusted with respect to a mobile plate, placed opposite and pivoting about one end of the yoke, is secured against movement by a wedge which is guided in a groove belonging to a flange of the coil shell.This device may be used in any thermal relay where a stable and precise adjustment of the tripping current threshold is desired.

Abstract: A circuit breaker having an overload mechanism including an elongated bimetallic element having one end pivotally mounted in the circuit breaker housing and the other end pivotally positioned at one end of an armature element. The armature element has a latching surface engaging a trip arm to hold it in a set position. An overload current causes the bimetallic element to bend. Since the ends of the bimetallic element are constrained, its central portion moves causing the armature element to pivot disengaging its latching surface from the trip arm. The released trip arm pivots to a tripped position causing the breaker contacts to be opened.

Abstract: A flux shifting type trip device, which is electrically activated under the control of a static trip unit to mechanically initiate tripping of a circuit breaker automatically in response to an abnormal current condition in a protected circuit, is equipped with a thermal responsive element operative to directly, mechanically activate the trip device and thereby initiate circuit breaker tripping automatically in response to an excessive ambient temperature condition within the circuit breaker enclosure.

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.