Harry C Nagel, Age 702817 Mccully Rd, Allison Park, PA 15101

4171788, Oct 23, 1979

May 8, 1978

5/903428

Harry C. Nagel - Murrysville PA

Westinghouse Air Brake Company - Swissvale PA

B61L 2106

246 40

At the remote end of a Type C track circuit, the conventional diode and the winding of a power transfer relay connected in multiple are connected across the rails over a transfer relay front contact. This transfer relay and the track relay at the near end are normally energized by the same half cycle of track current from the alternating current (AC) source. If the AC source fails, a track battery is connected across the rails at the remote end in series with the diode and transfer relay multiple network over a transfer relay back contact. The diode is so poled that the track relay is energized from the track battery with the same polarity as the rectified alternating current and does not release during the transfer operation. The diode bypasses substantially all track battery current away from the transfer relay. When the AC source is restored, the transfer relay is initially energized by the rectified alternating current through a low impedance capacitor, connected in multiple width the track battery and transfer relay back contact, and picks up to restore normal track circuit operation.

4301490, Nov 17, 1981

Jul 9, 1979

6/055864

Harry C. Nagel - Murrysville PA
John J. Kuhn - Allison Park PA

American Standard Inc. - Swissvale PA

H02H 720

361 89

A solid-state overload protection circuit for protecting a multiple-stage compound transistor power amplifier. The overload protection circuit includes a current-limiting circuit for sensing or limiting the current during an overload condition. The current-limiting circuit includes a transistor which conducts to limit the current in the output stages of the multiple-stage power amplifier. A monitoring circuit including a timing circuit, a comparator, and a switching transistor monitors the duration of the overload condition and disables the input stages of the multiple-stage power amplifier when a prolonged overload condition persists.

4619425, Oct 28, 1986

Jul 17, 1981

6/284150

Harry C. Nagel - Murrysville PA

American Standard Inc. - New York NY

B61L 2100

246 34R

An alternating current code, alternately transmitted in each direction through the rails of a railroad track section, includes a selected number of pulses of alternately positive and negative polarity similar to a bi-polar DC code. Data is transmitted by pulse length, with long and short pulses representing binary digits 1 and 0, respectively. The code pattern, polarity and pulse length, is balanced to eliminate code distortion by track energy storage. The code pattern transmitted is determined, and received pulses are decoded, by a microprocessor with associated memory (PROM) which processes local input and output data. The processor also checks the operation of the associated apparatus, including input and output circuit and hardware integrity through monitor devices and feedback signals. A unique check signal output is produced only when the various monitor networks determine all operation is proper and that the various elements are free of faults. The generation of operating energy for the associated apparatus by a power supply unit is dependent upon its continued reception of this check signal from the processor.