Abstract: The invention relates to a fuel cell (2) comprising at least one membrane/electrode unit (10) comprising a first electrode and a second electrode, which electrodes are separated from one another by a membrane, and comprising at least one polar plate (40) which comprises a first distribution region (50) for distributing a fuel to the first electrode and a second distribution region (60) for distributing an oxidation agent to the second electrode. The first electrode and the second electrode of the at least one membrane electrode unit (10) are electrically connected by means of a conductor (90). The invention also relates to a fuel cell stack (5) which comprises a plurality of the claimed fuel cells (2).

Abstract: A method for detecting a change of an impedance of a magnetic field receiver of a metal detector, including: having a first network of passive components, including the impedance of the magnetic field receiver; having a second network of passive components, excluding the impedance of the magnetic field receiver; and processing a first measurement signal from a first node of the first network with a second measurement signal from a second node of the second network to detect the change in the impedance of the magnetic field receiver; wherein the first network, the second network, the first node, the second node is configured such that in an absence of an external influence which affects the impedance of the magnetic field receiver, the first measurement signal is substantially the same with the second measurement signal; and in a presence of the external influence, the first measurement signal is different from the second measurement signal.

Abstract: An annular ceramic washer has inner and outer cylindrical surfaces, first and second annular surfaces, and a winding path thick film resistor located on the inner surface. Metal washers are preferably brazed to the end ring surfaces. The annular ceramic washer is useful in vacuum tube applications in establishing a voltage on a target utilizing the voltage of an electrode coupled to the winding path thick film resistor.

Abstract: The present invention relates to an electrical resistor (1), in particular for measuring alternating currents of high frequency, comprising connectors (2, 3) for feeding the current to be measured and connectors (4, 5) for tapping the voltage to be measured and having a layered structure including at least one resistive layer (10), a return conducting layer (11) and any possibly provided insulating layers (7, 12, 21, 22, 24). To obtain a measuring resistance having a particularly good frequency response, a high long-term stability and an efficient cooling and which, moreover, is inexpensive to produce, it is provided for the resistive layer (10) together with the return conducting layer (11) and the possible insulating layers (7, 12, 21, 22, 24) to be part of a multilayered printed circuit board and to comprise a plurality of conductive tracks (14) extending from a central region of the resistive layer (10) towards outside.

Abstract: The low-inductance resistance device with a bi-directional Archimedian spiral layout is to reveal a resistance element with a single-layer or multilayer reverse spiral layout, having such features as winding, in a bi-directional Archimedian spiral or reverse bend layout, coating-like, film-like, ceramic or metallic resistance material round a cylindrical core. In addition, the low-inductance resistance device maybe comprised of a single layer or multiple layers, as appropriate, facilitating the off-set of its magnetic line of force and the reduction in the resistor's inductance, so that it may be applied to high-frequency circuits.

Abstract: A wire-based heating element is provided having first and second portions twisted about each other such that magnetic flux emitted from one portion is substantially cancelled by magnetic flux emitted from the other portion. A bonding material that fixedly connects the two portions of the heating element and restricts their movement relative to each other to thereby maximize the cancellation of magnetic flux. A substrate-based heating element is also provided having traces on opposed sides of a substrate and overlying each other to cancel magnetic flux. Electrical connection pads are located on the same side of the substrate, and the second trace extends passed the first trace to connect to the second connection pad. A lead connected to the first connection pad overlies the portion of the second trace that extends to the second connection pad to thereby cancel magnetic flux emissions from this portion of the second trace.

Abstract: A wire-based heating element is provided having first and second portions twisted about each other such that magnetic flux emitted from one portion is substantially cancelled by magnetic flux emitted from the other portion. A bonding material that fixedly connects the two portions of the heating element and restricts their movement relative to each other to thereby maximize the cancellation of magnetic flux. A substrate-based heating element is also provided having traces on opposed sides of a substrate and overlying each other to cancel magnetic flux. Electrical connection pads are located on the same side of the substrate, and the second trace extends passed the first trace to connect to the second connection pad. A lead connected to the first connection pad overlies the portion of the second trace that extends to the second connection pad to thereby cancel magnetic flux emissions from this portion of the second trace.

Abstract: A heater coil for an electron tube includes a spiral wire which is double wound to be cylindrical, and a connection wire which is formed on an upper face of the spiral wire in a horizontal plane. The connection wire is shaped to have at least two bent portions on the same plane.

Abstract: A magnetic variable resistor has an elongated band of electrically resistive magnetic material, with the side edges tapered to a sharp point so that the skin effect causes current to migrate to the edges to create greater resistance. A layer of insulating material can cover the band as it is coiled. Leads are secured to opposite ends of the band. An alternate form of the invention embeds the coiled band in a magnetic insulating material. Surface mount leads are flush with at least one surface of the insulating material.

Abstract: A protection arrangement for a high voltage tube includes a low inductance disk resistor connected in series with the anode of the tube. When an electrical discharge occurs within the tube, the increased anode current flows through the resistor which absorbs much of the potentially harmful energy surge. The resistor is a disk resistor having two counter-wound planar spirals of resistance wire electrically connected in parallel and counter-wound with respect to one another. Connection arrangements are provided to both electrically and mechanically connect the resistor to the high voltage tube.

Abstract: An electrical resistor having first and second cylindrical resistance windings helically wound closely adjacent one another about a common axis and wound in opposite directions about such axis. The helical windings of the resistor are connected in parallel and the resistor is provided with terminals for placing it in series with a circuit to provide a resistance in such circuit. The resistors are used in a power distribution system that includes a first system connected to a second system by a tie line. The resistors referred to as braking resistors are located adjacent at least one of the power sources and are connected to the tie line through one or more circuit breakers.

Abstract: A film-type cylindrical resistor in which the end caps fit over the environmentally protective coating. Both the resistive film and the environmentally protective coating are applied by screen printing. Termination films are provided at the ends of the resistive film, and are electrically contacted by the end caps. The method comprises screen printing the resistive and termination films, and the environmental coating, and then mounting the end caps by interference-fit connections.

Abstract: A low inductance resistor for high current limitation is arranged from a single conductor wrapped in a continuous direction to form a plurality of turns wherein current transport through each of the turns induces a corresponding magnetic field to oppose the magnetic field induced within each next adjacent turn. The resistor finds application within a current limiter unit which employs magnetic repulsion and gas pressure to direct arcs that occur between separating contacts to within the high voltage region of an arc chute. The resistor is connected across the arc to reduce the arc current to a low enough value so that the arc becomes extinguished within a predetermined period of time.

Abstract: A discharge resistor adapted to be mounted on a rotatable shaft of a dynamo-electric device comprises a pair of spirally wound, insulated resistor elements and means for supporting these elements approximately coaxially with the shaft. Each of the resistor elements is spirally wound in a flatwise manner with a bore having an effective diameter greater than that of the shaft, and insulation layers are provided between adjacent turns thereof. The resistor elements are arranged and connected electrically in series such that the inductive impedance appearing across the respective resistor elements effectively cancel each other.