中科微点-全球专利检索

  1. Login
  2. Sign Up

Search Results

412 records (took 0.029 seconds)

    IMPROVEMENTS IN OR RELATING TO ELECTRICAL CONTROL CIRCUITS FOR BURNERS
    101.
    发明专利
    IMPROVEMENTS IN OR RELATING TO ELECTRICAL CONTROL CIRCUITS FOR BURNERS 未知

    公开(公告)号：GB1223057A

    公开(公告)日：1971-02-17

    申请号：GB2616468

    申请日：1968-05-31

    Applicant: ELECTRONICS CORP AMERICA

    IPC: F23N5/08 ,  F23N5/20

    Abstract: 1,223,057. Controlling burners. ELECTRONICS CORP. OF AMERICA. 31 May, 1968 [22 June, 1967], No. 26164/68. Heading F4T. [Also in Division G1] In a burner control system which includes a pilot fuel control 35, a main fuel control 36, an ignition control 34, a timer motor 30 to provide an initial purge period, an ignition period and a combustion interval, and a flame detector 26 sensitive to ultraviolet radiation, the circuit includes means responsive to the flame detector and normally has monostable characteristics so that there is an indication of flame only when the flame detector senses a flame condition, the system including an arrangement for converting the flame detector responsive circuit to a bistable mode in which flame continues to be indicated after the detector provides a transient flame condition signal during the initial period but returning the circuit to monostable condition prior to the ignition period to check the flame sensor and its circuitry for false indications of flame, a safety circuit shutting down the system in safe condition when a flame signal is provided for a predetermined interval of time during the said initial period. Detector 26 is of the Geiger-Muller type and is coupled by a resistor 60 to an inductor 62 having output lines 64, 66 coupled through diodes 68 to provide an input signal to a controlled rectifier 24. A mode conversion circuit connected across the controlled rectifier includes a resistor 108, capacitor 110 and timer contacts 30-13, the flame sensor circuitry being converted from monostable to bi-stable mode when at seven seconds the contacts 30-13 close. A purge cycle continues for twenty six seconds and then contacts 30-13 open to restore the circuitry to its monostable mode. If a flame signal is generated during this purge interval the flame relay remains energized whether the signal is transient or continuous. Current flows in a lock-out heater 32 of magnitude sufficient to open contacts 32-1 after a short time to de-energize control relay coil 20 and to close contacts 32-2 and signal an alarm. Contacts 20-3 are opened so that no ignition sequence may be initiated. The timer motor circuit is completed however and the timer motor runs until contacts 30-1 open at sixty seconds and the system is reset in a safe condition but cannot be restarted until switch 32 is manually reset. If no false flame signal is generated during the bi-stable mode interval and ignition takes place the combustion cycle continues until the call for heat is terminated by the opening of switch 16. Flame failure causes lockout heater 32 to be energized so that the system is locked out.

    102.
    发明专利
    未知

    公开(公告)号：FR2011108A1

    公开(公告)日：1970-02-27

    申请号：FR6920157

    申请日：1969-06-17

    Applicant: ELECTRONICS CORP AMERICA

    IPC: F23N5/18 ,  F23N5/20 ,  F23N5/00 ,  G05B19/00

    Abstract: 1,262,947. Controlling burners. ELECTRONICS CORP., OF AMERICA. 29 May, 1969 [17 June, 1968], No. 27171/69. Heading F4T. Burner control apparatus for use with a fuel burner installation having a combustion chamber, a fuel flow control 28 and an ignition control 26 comprises four timing circuits containing respectively unijunction transistors 50, 70, 90 and 110. Operation commences when switch 14 is closed, thereby energizing damper control 22 and main control relay 20. This relay closes contacts. 20-1, to energize blower 16, and also closes contacts 20-2. When air flow has been established in the combustion chamber, flow switch 16-1 closes. If at this stage detector 62a generates a spurious flame signal, indicating a fault in the installation, transistor 86 becomes conducting and energizes flame relay 82. Contacts 82-2 are thereby closed to complete a current path to coil 44. This in turn opens contacts 44-1, de-energizing the circuit, and closes contacts 44-2 to sound an alarm. If there is no spurious flame signal, the sequence of timing operations commences. The first timing circuit, containing transistor 50, controls a first, or pre-purge, timing interval (T1, Fig. 3, not shown). When the potential on capacitor 52 exceeds that on the emitter of transistor 50, the capacitor discharges through this transistor to energize the coil 60. When this happens contacts 60-1 open; contacts 60-2 close, completing a holding circuit for coil 60; contacts 60-3 close, energizing the second and third timing circuits; contacts 60-4 open, deenergizing damper control 22; contacts 60-5 close, energizing pilot fuel control 24 and ignition control 26; contacts 60-6 open, cutting off transistor 86 from the power supply; contacts 60-7 open; and contacts 60-8 close. At this stage, pilot fuel is flowing and ignition control 26 is operating, but since transistor 86 is not energized, detection of ignited pilot fuel will not result in energization of relay 80 and consequent shut-down of the installation. The second timing circuit, containing transistor 70, is energized when contacts 60-3 close and controls a second timing interval (T2). When a portion of the corresponding relay 82 is energized thereby energizing the fourth timing circuit, contacts 82-1 open; contacts 82-2 close; contacts 82-3 open to de-energize the ignition control; contacts 82-4 close to energize transistor 86 and thereby provide a holding circuit for coil 82 if flame is present; and contacts 82-5 close. The third timing circuit, containing transistor 90, is also energized when contacts 60-3 close and controls a third timing interval (T3), longer than the second. When the relay 98 is energized, contacts 98-1 open; contacts 98-2 close, providing a holding circuit for coil 98; contacts 98-3 close; and contacts 98-4 close to initiate fuel flow into the combustion chamber, where the fuel is ignited by the pilot flame. The fourth timing circuit, containing transistor 110, is energized when coil 82 is energized and controls a fourth timing interval (T4). When transistor 110 becomes conducting, transistor 120 is rendered non-conducting and coil 60 is de-energized. Accordingly, contacts 60-1 close; contacts 60-2 open; contacts 60-3 open, deenergizing the second and third timing circuits; contacts 60-4 close, re-energizing the damper; contacts 60-5 open, de-energizing the pilot control; contacts 60-6 close; contacts 60-7 close, establishing a holding circuit for coil 98; and contacts 60-8 open. Should flame failure occur after main fuel flow has started, transistor 86 will cease conducting and coil 82 will be de-energized. Thus, contacts 82-1 close to energize lock-out actuator 44. Contacts 44-1 open, disabling all the relays and their associated controls, and contacts 44-2 close, energizing the alarm 18. Should air flow cease at any time, switch 16-1 opens to deenergize the relays and shut down the installation in a safe condition.

    103.
    发明专利
    未知

    公开(公告)号：DE1526223A1

    公开(公告)日：1969-12-04

    申请号：DE1526223

    申请日：1966-09-02

    Applicant: ELECTRONICS CORP AMERICA

    Inventor： GIUFFRIDA PHILIP ,  PRATT JOHN

    IPC: F23N5/08

    Abstract: 1,101,630. Photo-electric flame sensor. ELECTRONICS CORPORATION OF AMERICA. Aug.18, 1966 [Sept.2, 1965], No. 36983/66. Heading G1A. An avalanche breakdown type of detector sensing ultraviolet radiation from a flame is fed with A. C. via a circuit which is resonant at a frequency substantially greater than the A. C. frequency. When the detector is in its low impedance avalanche breakdown, so that each half cycle current flow through the detector upon avalanche is quenched before the A. C. changes polarity. As shown in Fig. 2 600V. A. C. are fed to a detector 116, comprising tungsten electrodes in a hydrogen atmosphere, through capacitor 112 and inductance 120 which together form the required resonance circuit. The inductance 120, which is an autotransformer, reflects pulses created by each half cycle avalanche via diodes 134, 136 to charge capacitor 150 which slowly discharges into capacitor 164. If pulses arrive at a sufficient rate, the controlled rectifier 160 is made conductive and current flows through relay coil 162. A capacitor may be provided on the primary side of transformer 100 to provide a circuit which is resonant at the A. C. frequency. In another arrangement Fig. 1 (not shown) the detector is in the secondary circuit of an autotransformer whose primary circuit together with a capacitor forms a circuit which is resonant at the A. C. frequency when the detector has not broken down but resonant at a much higher frequency when the detector has broken down. Circuitry for collecting the breakdown pulses is similar to Fig. 2. In a third arrangement Fig. 3 (not shown), the required resonant circuit comprises a capacitor bridging the detector and inductor in series.

Patent Agency Ranking