Communications: electrical – Condition responsive indicating system – Specific condition
Patent
1980-02-06
1982-02-16
Caldwell, Sr., John W.
Communications: electrical
Condition responsive indicating system
Specific condition
310245, 310249, G08B 2100
Patent
active
043161863
ABSTRACT:
A wear-indicating brush and warning circuit is adapted to convey an indication that a dynamoelectric machine is in need of maintenance before the brush wears to the point that a rotor contact surface is damaged by contact with electrical connections to the brush. A brush (10) having current carrying pigtail leads (16) embedded therein includes a wear-detecting wire (20) embedded in the brush a short distance (A) beyond the lowest extent of the pigtail leads (16). The wire (20) is insulated over its periphery, including its tip (24), the insulation (26) being abraded by contact with the rotor contact surface (50), so that the wire (20) senses the voltage present thereon. Non-latching warning circuits (66, 66a), with and without the use of an isolating resistor within the dynamoelectric machine to permit the use of a single wire between the machine and the warning circuit to provide a brush wear indication. Also disclosed is a warning circuit for indicating that an input is electrically connected to a voltage, for indicating that a line (20) has contacted a rotor contact surface. The voltage sense may be negative or positive, over a wide range, so that the positioning and number of brushes (10) is irrelevant. The circuit (92) includes an oscillating voltage source (122) and comparison circuits (124, 126, 128) giving a warning indication when an input line is connected to a voltage and is unable to follow the oscillating voltage.
REFERENCES:
patent: 2590796 (1952-03-01), Schaffer
patent: 2691114 (1954-10-01), Lykins
patent: 2700760 (1955-01-01), Brown
patent: 2814684 (1957-11-01), Pascale
patent: 3439206 (1969-04-01), Grannells
patent: 3523288 (1970-08-01), Thompson
patent: 3681635 (1972-08-01), Bayer
patent: 3898492 (1975-08-01), Vassos et al.
patent: 4024525 (1977-05-01), Baumgartner et al.
patent: 4121207 (1978-10-01), Jones
patent: 4172988 (1979-10-01), Lowther
Dudley Carl K.
Purdy James A.
Caldwell Sr. John W.
DeClercq James P.
Eltra Corporation
Myer Daniel
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