Abstract: A circuit interrupter includes a circuit arrangement for sampling a conditioned current value and determining operating characteristics related to the current flow through an electrical circuit. Also included is a circuit arrangement for comparing the operating characteristics to preselectable tripping parameters and for initiating a trip condition when an operating characteristic exceeds a corresponding tripping parameter. Additionally, a fault indicating circuit arrangement energized by a backup energy source following interruption is also included as well as circuit arrangement for preventing interference to the display and operating circuits during power-up and power-down conditions.

Abstract: A transceiver provides a relatively constant output voltage from its linear amplifier by providing both current and voltage feedback to its operational amplifier. The present invention utilizes common components for both transmitting and receiving and provides an apparatus which can both transmit and receive power line carrier signals which can be used to communicate digital data through phase modulation of the carrier signal. The transceiver of the present invention can be operatively connected to a microprocessor through appropriate filtering and switching.

Abstract: Apparatus for detecting gap-type defects in power line equipment in response to broadband radio frequency noise generated by such faults. The apparatus includes a radio receiver coupled to an antenna to receive the noise and provide first signals responsive thereto. Squelch circuitry attenuates the first signals below a predetermined magnitude and outputs second signals responsive to first signals which exceed the predetermined magnitude. Sample and hold circuitry provides third signals in response to the second signals, i.e. in the time periods in which the second signals are not squelched. Filter circuitry separates gap noise from other local noise by determining the periodicity of the third signals, providing fourth signals in response to third signals having a predetermined repetitive rate. Indicator circuitry responsive to the fourth signals identifies the times in which periodic noise indicative of gap-type noise is detected.

Abstract: An FM antenna utilizes a generally rigid conductive element, as a dipole segment, that is connected in electrical communication with a capacitive segment. The capacitive segment can be manufactured from a preselected length of coaxial cable with the central conductor of the coaxial cable being connected in electrical communication with the dipole segment and with the cylindrical conductor, or braided shield, of the coaxial cable being connected to an electrical ground. A variable inductor is connected in electrical communication with the central conductor of the coaxial cable between the capacitive segment and an FM receiver. The central conductor of the capacitive element is connected serially between the dipole segment and the variable inductor. This configuration provides an omnidirectional antenna for use with FM receivers that is relatively small in size and inexpensive to manufacture.

Abstract: An electric meter is provided with a magnetically sensitive switch and a means for detecting the activation of the switch. A program is provided for sensing, recording and transmitting the status history of the magnetically sensitive switch to a remote device. The electric meter is connected in signal communication with a power line communication system and provided with the capability of transmitting and receiving messages in conjunction therewith. The electric meter senses the presence of a strong magnetic field in the region of the electric meter and, if other appropriate flags are not set, this information is used to determine that an effort to tamper with the meter by using magnetic fields has occurred.

Abstract: A dual-piston hydraulic brake master cylinder includes a large hydraulic piston which supplies an initial large brake fluid volume and a small hydraulic piston which continues to supply brake fluid to the brakes when the large piston stops moving forward in its cylinder at higher brake pressures. The small, central hydraulic piston is connected to the end of a piston rod extension of a pneumatic booster piston. The large piston surrounds the small piston and opens a reservoir line tilt-valve in the piston retracted position. A passageway between the large and small hydraulic chambers is open in the retracted position to allow communication of braking fluid therebetween. During brake actuation a seal arrangement interrupts this communication. The large and small hydraulic chambers supply the brake circuits through delivery passages.

Abstract: A gearshift range preconditioning system includes a gearshift device which, when manually-operated to effect a gear-change, initiates a signal to an electronic logic circuit which is coupled to the vehicle to receive vehicle-operating characteristics such as speed and engine RPMs. The electronic logic circuit evaluates this change request and the received operating characteristics in relation to predetermined optimum operating characteristics associated with optimum neutral gear ranges. The electronic logic unit then generates a neutral gear signal which is transmitted to a solenoid-valve-controlled neutral gear cylinder to effect operation of the vehicle transmission into the neutral position best suited for the specific vehicle-operating characteristics. An auxiliary range cylinder can effect selection of active gear positions between a high and a low state to achieve a doubling of possible active gear positions.

Abstract: A pulse train presence detector for a system having a number of interruptible devices, consists of a pulse generator, interface device which receives a periodic trigger signal and outputs a pulse train signal in response thereto, the pulse train signal is communicated to an NPN transistor and operates the transistor to alternating "on" and "off" states. A first current path is established during the transistor "off" state through which a first current flows and charges a first capacitor. A second current path branches off from the first current path, wherein a second current flows when the transistor is "on". A forward-biased diode in the first current path and an adjacent reverse-biased diode in the second current path block cross-flowing of currents between the respective paths. A second capacitor in the second current path is charged when the transistor is "on".

Abstract: A contactless proximity switch and mounting arrangement for determining the position of a movable member within a cylinder which has two end covers secured on the cylinder by means of a plurality of tie rods, includes a switch housing which secures to one of the tie rods. A contact opening formed in the switch housing has disposed therein, a switch having a pair of contacts and a permanent magnet disposed in a fixed manner. One pole of the permanent magnet is connected to a first contact, while the second pole is disposed in a contacting relation to the cylinder. A second contact is electrically coupled to the cylinder at a position a predetermined distance from where the second pole is disposed. As the movable member, which is constructed of a ferromagnetic material, nears the switch housing, the air gap between the second contact and second pole is bridged and the contacts close indicating the proximity of the movable member to the switch element.

Abstract: A fluid flow control apparatus having an adjustable throttling arrangement for controlling the flow of fluid between working cylinders associated with sections of an articulated vehicle, has a housing which is essentially symmetric in shape. Two working connections are formed at symmetrically opposite ends of the housing and connect to the working cylinders. Two passageways, formed in the housing to connect the two working connections, are also symmetrically formed and are approximately equivalent in length. The first passageway uses a check valve arrangement to restrict fluid flow from the first working connection to the second working connection while the second passageway uses a similar check valve arrangement to restrict fluid flow in the opposite direction. The two passageways interconnect at a crossover duct which acts as a guide for the throttling arrangement.

Abstract: A combination gear-selector, sensor device for use with vehicle transmissions having a plurality of gear positions and certain special gear functions and being controlled by an electronic circuit includes a shift lever having a first, square magnet which, when moved over distinct gear position sensors, indicates selection of a certain gear. A rod coaxially disposed within the shift lever has a second, rectangular magnet, displaced to one side of the first magnet, which when vertically moved over a first function sensor, indicates selection of that function which can be to skip a gear. A coaxial tube surrounds the rod member within the shift lever and has a third, rectangular magnet, displaced to an opposite side of the first magnet, which can be moved over a second function sensor to indicate selection of a second special function.

Abstract: The invention relates to an electromagnetically-operated multi-way valve, which exhibits two valves (an inlet and an outlet) opposite one another. Corresponding to each of the two valves, there is an armature which interacts with a coil, located between the two valves. A coil bracket, disposed through the coil, has a passageway which, upon certain valve conditions, allows communication from the inlet valve to the outlet valve. One of the two valves can be activated against the force of a first spring by the first armature, and the other of the two valves can be activated against the force of a second spring by the second armature. The two springs are designed so that different magnetic forces are required to operate the two valves. The different magnetic forces are produced by a change of the current flowing in the coil. Since there is a separate armature for each valve, which can be operated by one current-controlled coil, it is possible to operate the two valves independent of one another.

Abstract: A position-sensing potentiometer arrangement for sensing the position of a movable piston and piston rod configuration within a linear actuator includes a first support member extending longitudinally within an open-ended recess formed in the rod and a sliding contact mounted thereon. A tubular support is mounted to a stationary closed end of the linear actuator and extends into the recess to surround a portion of the first support member and a center support member which is also mounted on the closed end of the a actuator. A longitudinally-extending resistance element and a parallel conductor element are mounted on and supported by the center support member. As the first support member moves through the tubular support, the sliding contacts couple the resistance element to the conductor element to provide a resistance value variable as a function of the position of the piston rod.

Abstract: A work cylinder having a piston of single-body construction and a cushioning arrangement integrally formed on the piston includes a cylinder housing having a chamber formed therein divided into first and second work chambers by the piston. First and second piston extensions extend into first and second graduated chamber portions formed at opposite ends of the cylinder housing. A sealing material, bonded to the exterior surface of the piston, exhibits a dual cup-shaped piston seal around the center portion and annular cushion seals on the piston extensions. The cushion seals are at an angle such that, when in contact with a first chamber reduction, a seal results. Additionally, in the opposite direction, the cushion seals act as a check valve whereby fluid pressure introduced to a second chamber reduction depresses the cushion seals and flows into the selected work chamber.

Abstract: A vital inverter driver includes an oscillator which, upon energization, outputs a signal of predetermined frequency to two identical parallel-arranged counter circuits, which step down the oscillator output to the desired frequency. One counter output is fed to an inverting amplifier, while the other is coupled to a noninverting amplifier, thereby resulting in output count signals of identical frequency and amplitude but being 180.degree. out of phase. A summing circuit, having two series-resistance arrangements with different resistance values for weighting purposes, and a summing transformer passes a signal of a predetermined magnitude through an overload protection device which could be a fuse or a breaker, when the output count signals are 180.degree. out of phase. When the count signals are other than 180.degree.

Abstract: A mechanical release arrangement for a fluid-pressure-operated braking cylinder having an emergency brake/parking brake feature includes a cylinder housing having formed therein a brake actuation portion, an emergency portion, an intermediate lever portion, and a coaxially-disposed brake-release arrangement interacting therewith. An actuator piston is movable within one pressure chamber and has a hollow rod portion extending therefrom on which the lever arrangement is secured. An emergency piston is retracted to a release position against the force of a spring arrangement by fluid pressure communicated to an emergency chamber. An extension sleeve extends from the emergency piston and has a first toothed portion formed at one end. A release rod extends through the extension sleeve and has a second toothed portion formed near a reduced diameter end.

Abstract: An arrangement for determining the position of a core within a coil improves a voltage across the coil upon generation of an initiating voltage pulse. The initiating voltage pulse can originate from a microprocessor or other electrical timing logic circuit. The charging current in the coil is developed from this initiated time until either a predetermined current level is reached in one embodiment or a predetermined time duration is reached in another embodiment. A microprocessor or other electrical measuring circuit measures either the time duration to reach the predetermined current level or the discharge time following current charging for the predetermined time duration. A microprocessor or other electrical logic circuit derives the core position from the measured time to reach the predetermined current level or the measured discharge time following current charging for the predetermined time duration.

Abstract: A fail-safe voltage-limiting circuit for an audio frequency-controlled railway track circuit includes a pair of NPN transistors arranged in the manner of a darlington pair, wherein the base connector of the first transistor receives an amplitude-modulated signal from a filter and detector circuit connected to the rails. A first pair of resistors arranged in series between the positive and negative system battery lines, includes a first fail-safe resistors also connected to the collector of the first transistor. The ratio of the first and second resistors are selected to limit the positive excursion of the input signal, thus clipping excess noise at this limit. A second pair of resistors is coupled to the second transistor to limit the negative excursion of the amplitude-modulated input signal. The second pair of resistors includes a second fail-safe resistor connected to the emitter of the second transistor and a third resistor connected in series to the second fail-safe resistor at this junction as well.

Abstract: A propeller pitch controlling arrangement having a fuel economizer feature for use on marine vessels, has a mode selector valve operable to a normal mode and an economizer mode. In the economizer mode, a first pilot signal is transmitted to a path selector valve to establish a first flow path to a propeller pitch servomechanism. A second pilot signal is transmitted from a relay valve when the marine vessel speed drops below a predetermined value. The second pilot signal moves the path selector valve to a second position establishing a second flow path to the propeller pitch servomechanism. A first selected fluid pressure from a regulating valve arrangement mechanically linked to the engine fuel rack, is directed to the propeller pitch servomechanism when the first flow path is established. This first selected fluid pressure is proportional to the movement to the engine fuel rack.

Abstract: A fluid-pressure-operated, double-acting working cylinder which dampens the final braking of the work piston, includes a cylinder housing with a movable work piston disposed therein, the work piston dividing the cylinder into two work chambers. A piston rod, on which the work piston is mounted, extends through the housing. At least one auxiliary braking member is disposed on at least one side of the work piston in an offset slidable relation to the work piston. A braking arrangement disposed on the auxiliary braking member is controlled by fluid pressure to brake the auxiliary braking member to a desired position within the cylinder. A dampening chamber, a dampening spring configuration is disposed between the auxiliary braking member work piston such that, following braking of the auxiliary braking member, continued movement of the work piston is effectively dampened.