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    1.
    发明专利
    未知

    公开(公告)号：DE1401937A1

    公开(公告)日：1968-11-21

    申请号：DE1401937

    申请日：1960-07-20

    Applicant: ELECTRONICS CORP AMERICA

    Inventor： GRAVES DONALD L

    IPC: F23N5/08 ,  F23N5/22

    Abstract: 906,682. Controlling burners. ELECTRONICS CORPORATION OF AMERICA. Aug. 17, 1960 [Aug. 31, 1959], No. 28565/60. Class 75 (1). [Also in Group XL (b)] A device for the automatic control of a burner comprising a pilot valve, ignition means, and a main fuel valve, comprises a detector primarily sensitive to U.V. radiation, flame relay means actuated thereby, and a timer which has a plurality of switches to turn on the ignition means and a pilot valve during a first time interval, to turn off the ignition means during a second time interval, and to then turn on the main fuel valve only if the detector has sensed a flame during the second interval. In response to the closing of a thermostatic switch 21 a relay 23 operates to switch (via its contact 87) power on to a timer motor 99 and a burner motor 11, which supplies air to the burner initially for purging and then for combustion. After ten seconds motion of the timer its contact 101 is closed to hold the supply to the burner motor and its contact 73 is opened so that relay 23 is held operated only by connection via its contact 81 and the resistive coil 41 of a thermal lockout switch 39. After a further twenty seconds, timer contact 103 is closed to energize an ignition transformer 17 and a pilot fuel valve 15 and consequent upon the sensing of U.V. radiation by the detector 33 from either the flame or ignition the flame relay 27 is caused to operate. Five seconds later timer contacts 107 and 115 are opened so that the ignition transformer is de-energized but the pilot fuel continues to be energized via contact 125 of flame relay 27. After a further five seconds timer contact 127 is closed to connect power on to a main fuel valve 13. In the event of flame relay 27 being deenergized due to failure of the pilot flame or the main flame both fuel valves are disconnected by the opening of flame relay contact 125 and the simultaneous switching of the contact 77 removes the shunt across the resistive coil 41 of the thermal lockout switch 39 which then operates to de-energize relay 23 and operate an alarm 19; manual intervention is then necessary to restore the switch 39. If, however, the cycle proceeds normally, some time after the main fuel valve 13 has been switched on timer contact 95 is operated to disconnect the timer motor. Shutdown, initiated by the opening of the thermostat switch 21, results in the main fuel valve 13 being disconnected and relay 23 being de-energized, this latter causing restoration of its contact 87 to connect power to the timer motor 99, which then rotates to restore the initial circuit conditions. The circuit is stated to fail safe in the event of power failure. .

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