Abstract: A plastic fastener assembly is provided which has a base with an upstanding stab which has a single first tooth formed on one side of the stab and at least one second tooth formed on the opposite side of the stab. A cover defines an opening for receiving the stab. The cover has a control rail adjacent the opening and a flap extending into the opening opposite the central rail. The rail slides along the surface of the first tooth during assembly and urges the first tooth and stab toward the flap until the rail engages the notch of the first tooth. The flap automatically moves from the base during assembly as the first tooth and stab move toward the flap. The flap engages the second tooth when assembled inhibiting separation of the stab and cover.

Abstract: A contact assembly for electrical circuit breakers has a contact lever and a lever support with the contact lever mounted thereon in an articulate fashion. The support lever is flexibly positioned around a fixed pivot bearing by a drive linkage device for on- and off-switching cycles. A pressure lever is used to introduce a current-dependent force onto the contact levers in order to increase the contact force. The pressure lever is similarly flexibly mounted onto the lever support. The contact lever and the pressure lever operate jointly via their working surfaces which permit a conveyance of force in terms of an increase of the contact force. When switching on the contact assembly, the pressure lever is decoupled from the contact lever so that the tendency to bounce is reduced.

Abstract: An inductive load 1, more specifically a direct current motor, is fed by a direct current source through a semiconductor regulator which contains two parallel switching controllable semiconductor rectifier elements with identical conduction direction which in turn are in series with a respective one-half of center tapped output autotransformer. Parallel to the semiconductor regulator is an additional and identical semiconductor regulator. The center tap points of both semiconductor regulator autotransformers are connected with the terminals of a third output autotransformer which is similarly center tapped, whereby the center tap point of the third output autotransformer is connected to a terminal (+) of the inductive load. The control assembly is made in such a manner that it produces clock frequency signals with identical control levels for both semiconductor rectifier elements; however, these signals for the two parallel switching arrangements are, electrically offset by 90 degrees.

Abstract: A current limiting circuit breaker is provided which has a stationary contact assembly and a movable contact bridge. A contact carrier is connected to the contact bridge and biases the contact bridge toward the closed position. The downward biasing force on the contact bridge is mechanically reduced in response to a preselected amount of opening movement of the contact bridge.

Abstract: An nth order magnetic multipole arrangement for influencing the trajectory of charged particles is disclosed. In order to avoid using structural parts that are manufactured separately, it has been found to provide as the multipole arrangement, the stator of a multi-pole alternating current machine, the stator winding of which is fed by a voltage source in such a way that the produce of current and number of turns (number of ampere turns) in a groove or group of grooves disposed under the azimuth angle .theta. is proportional to cos (n .theta.), n corresponding to the order (order number) of the multipole arrangement, and the factors a and b being taken from the ratio b/a which states the orientation of the multipole relative to the azmith angle .theta.=0. As the multipole arrangement there may be provided also a stator, excited by permanent magnets, of a direct current machine.

Abstract: A microprocessor based trip unit for a circuit breaker is disclosed. The instantaneous current magnitudes in each phase and in the neutral of the circuit being protected are simultaneously and sequentially sampled by respective sample and hold circuits. The measured values are then applied to a respective analog-to-digital converter and the digitized values are sequentially applied to a microprocessor. The microprocessor calculates true RMS current and sums the signals of all phases and neutral to determine presence and magnitude of a ground fault current. To permit use of an 8-bit microprocessor, while maintaining high resolution of measured current over a large range, novel automatic scale adjustment is provided. The memory of prior thermal history of the circuit breaker is provided electronically by a capacitor circuit which is discharged at a rate representative of the rate of cooling of the circuit breaker.

Abstract: A stationary contact assembly is provided for a current limiting circuit breaker. The contact assembly includes a curved input arm which has a contact fastened thereon and a generally straight output arm which also has a contact fastened thereon and which has an opening for receiving the contact end of the input arm. The contacts are encapsulated in an insulating material which separates the contact arms from each other. A magnetic element is also embedded in the encapsulation material between the input and output contact arms. As current flows through the contact arms, a field is developed about the magnetic element which draws in an armature which reduces the opening force of the contacts.

Abstract: A current transformer is provided for the electronic trip unit of a molded case circuit breaker. The current transformer has a core with a winding encoiled about the core and a bus spiraled about the core. The spiral bus establishes a current path from one end of the bus to the other which will conduct current through the core in a spiral fashion. The spiral bus design effectively rotates the bus 90 degrees achieving a narrow transformer design which fits into the electronic trip unit without increasing the width of the trip unit.

Abstract: A magnetic structure is provided for calibrating a circuit breaker. The magnetic structure includes an E-shaped core which has an adjustable center post for varying the magnetic force between the core and armature by changing the gap between the center post and the armature. Variations in the field for a given current allow the tripping current for the circuit breaker to be precisely calibrated.

Abstract: A system for operating electrical equipment such as circuit breakers from a remote point is disclosed. A flexible push-pull type cable connects a linkage coupled to a pivoted handle and to a remote slider mechanism. The slider serves as a slave operator to effect reciprocation of a handle or similar operator element.

Abstract: The average winding diameter of a finite roller band length wound on a supply coil is increased by having the roller band rewound from the supply coil to a storage coil of a larger than the winding diameter, which encloses the supply coil concentrically. During the uncoiling of the band stored on the storage coil for purposes of a continuous manufacturing operation, a welding device is arranged in the annular area between the external diameter of the supply coil and the internal diameter of the storage coil and welds the band trailing end of the storage coil together with the band and leading end of the supply coil. The contents of the supply coil are then taken over by the storage coil, and while this material is uncoiled, a further supply coil is inserted and its leading edge welded to the end of the storage coil.

Abstract: An a.c. contactor with an armature activated by a magnetic system, which is effectively connected to a return spring-loaded contactor onto which the movable contact component of the contact system is mounted. The contact carrier is herein fitted with an auxiliary mass and placed in effective contact with the armature by a coupling spring, wherein the auxiliary mass is movable in relationship to the contact carrier and an additional spacer bar component, with which the armature is coupled. The coupling spring supported on one end by the contact carrier, can on the other end connect to an offset end of the spacer component which is pressed against the auxiliary mass, whereby the auxiliary mass connects with a catch of a contact carrier or else is spring-loaded against the direction of motion of the contact carrier towards a stop on the contact carrier via a separate auxiliary spring. These improvements dampen and delay the recoil of the contact carrier experienced during switching of the a.c. contactor.

Abstract: A simple and space-saving, nevertheless effective and low-noise apparatus for the interior compartment air of a motor vehicle, to impact a temperature sensor of an automatic heating or air-conditioning system is provided. This invention achieves these results by providing, in place of a separate auxiliary fan, an auxiliary air current drawn from the interior compartment and sensing the temperature of that current with a sensor. The impeller of the fan used for circulation in the interior compartment is also equipped with supplemental blades outside its actual main air current to generate an auxiliary air current which is drawn through a separate air channel from the interior compartment passing over the sensor. This air channel, such as a flexible hose, is suitably mounted between the air discharge opening on the dashboard and an air-feed opening in the spiral housing backwall of the fan.

Abstract: A disconnect switch for metal-enclosed, compressed gas-insulated high-voltage switchgear, having two resistors for the suppression of high-frequency oscillations caused by the occurrence of a pre-flashover arc, each located along the longitudinal axis of and electrically connected to a moveable rod. Furthermore, a movable insulating tube covers the disconnect gap substantially before the resistors make or break contact with each other. Each resistor is comprised of several resistive elements which lie adjacent to one another between two contact plates at each end and are molded of hardened cast resin. Each element is comprised of a ceramic plate with baked-on strips of resistive material which have contacts on all four edges.

Abstract: A voltage regulator using electronic control of two static switch circuits to permit tap changing without arcing at the switched electrical contacts, without interrupting the load current, and without inducing sizable circulating currents. As a mechanical drive connects a new tap to the auxiliary winding, current through the new winding is blocked by an auxiliary static switch. The drive next opens the main switch delivering current to the load. The opening of the main switch immediately allows the main static switch circuit to "turn on" to prevent arcing and load interruption until the next current zero. The main static switch control senses no current passing through the main switch and ceases gating, and therefore conduction, of the main static switch. Since neither the main static switch nor the auxiliary static switch is conducting current from the auxiliary winding, the load voltage begins dropping and the voltage across the auxiliary static switch begins rising.

Abstract: An electrical machine in which power is supplied to the rotor via brushes and sliprings having an improved brush-dust suction apparatus, including brush supports and ring-shaped collecting chambers which are penetrated by brush bolts. The suction openings of these collecting chambers circumscribe the slipring in a ring pattern. Each collecting chamber is connected by thick-walled glass cylinders to a common collecting chamber, which is connected to a negative pressure source, when the air and the brush dust entrained in the air is conveyed to an exterior chamber. The brush supports are fastened by insulators to the collecting chamber and are mutually reinforced by insulator bolts.

Abstract: A method for producing a winding for large AC salient pole dynamoelectric machine comprising winding an array of conductors in edgewise fashion about a pole body and then securing the conductor ends such that the array forms a single layer edgewise wound conductor.

Abstract: This invention pertains to a three-phase reversing contactor with fixed-mounted contact parts serving the input and the output, and a connection by contact bridges from the input to the output. A common drive mechanism is provided for all the contact bridges, and a shift mechanism to change the configuration of the contact bridges, while in the OPEN position, relative to the fixed-mounted contact parts is also provided. Through the application of the two independently movable contact bridge carriers, which by use of an auxiliary magnet can be selectively brought into functional contact with the common drive mechanism by a reversing yoke, the drive output for the auxiliary magnets can be kept low. As there is a fixed configuration of contact bridges to the fixed-mounted contact parts, the major wiring work can be performed in the shop by the use of correspondingly formed fixed-mounted contact parts.

Abstract: A method of sealing cavities open on one side, preferably cavities of electrical equipment housings fitted with various components. A measured quantity of an encapsulant, preferably polyurethane foam, is inserted into the cavity. Thereafter the opening is covered by a permeable, absorbent fabric, preferably of polypropylene, which is covered first by an elastic and then a rigid layer. After hardening, the fabric is removed from the surface of the encapsulant.

Abstract: A switching device is provided for electrical switchgear, particularly contactors. The switching device includes a step-shaped, bowed current lead with a contact portion cooperating with a contact portion of a switch bridge. The switching device also includes a U-shaped arc chute and a fastening bolt. The arc chute surrounds the contact portion with an air gap so that the electrical connection is made solely via the fastening bolt. The edge portions of the arc chute are set back in the area of the contact portion so that the contact portion of the contact bridge cannot come in contact with the arc chute even though the contact bridge may be obliquely positioned.