Burner control system

Claim 2

Burner control apparatus for use with a fuel burner installation having a combustion chamber, means to apply a request for burner operation signal to the burner control apparatus, combustion chamber ignition and fuel supply means, and flame sensing means for sensing the presence of flame in the combustion chamber, comprising: a burner lock-out switch and a lock-out switch actuator, control means for said combustion chamber ignition and fuel supply means, flame indication means responsive to said flame sensing means to produce a signal indicative of the flame condition in said combustion chamber, first and second energizing circuits for said lock-out switch actuator, said first energizing circuit including a latchable switch means adapted when triggered to latch in a closed mode for the duration of a request for operation signal, said seCond energizing circuit including first and second switch means connected in series, said first switch means adapted to close and open respectively in response to the presence and absence of a request for operation signal, said second switch means adapted to close and open respectively in response to flame and no-flame indications from said flame indication means, and circuitry cross-coupling said latchable switch means with said first switch means, said circuitry including a trigger circuit responsive to said first switch means being closed to trigger said latchable switch means, and a feedback circuit responsive to said latchable switch means closing to reset said first switch means in an open mode.

Claim 3

The burner control apparatus of claim 1, wherein said second switch means is connected in a circuit to override said trigger circuit and prevent triggering of said latchable switch means when said second switch means is closed.

Claim 4

The burner control apparatus of claim 1, and further including an additional switch means connected in said first energizing circuit in series with said latchable switch means, said additional switch means adapted to close and open respectively in response to no-flame and flame indications from said flame indication means to respectively enable and prevent completion of said first energizing circuit.

Claim 5

The burner control apparatus of claim 1, wherein said latchable switch means is connected to said control means to enable latching of said control means in an energized state when said latchable switch means is latched.

Claim 6

Burner control apparatus for use with a fuel burner installation having a combustion chamber, means to apply a request for burner operation signal to the burner control apparatus, combustion chamber ignition and fuel supply means, and flame sensing means for sensing the presence of flame in the combustion chamber, comprising: a burner lock-out switch and a lock-out switch actuator, control means for said combustion chamber ignition and fuel supply means, flame indication means responsive to said flame sensing means to produce a signal indicative of the flame condition in said combustion chamber, first and second switch means connected in series to complete a first energizing circuit for said lock-out switch actuator, said first switch means also being connected to said control means and adapted to latch said control means for the duration of a request for operation signal, said second switch means adapted to close and open respectively in response to no-flame and flame indications from said flame indication means, and third and fourth switch means connected in series to complete a second energizing circuit for said lock-out switch actuator, said third switch means also being connected in a trigger circuit for said first switch means and responsive to a request for operation signal to complete said trigger circuit, said fourth switch means adapted to close and open respectively in response to flame and no-flame indications from said flame indication means.

Claim 7

Burner control apparatus for use with a fuel burner installation having a combustion chamber, means to apply a request for burner operation signal to the burner control apparatus, combustion chamber ignition and fuel supply means, and flame sensing means for sensing the presence of flame in the combustion chamber, comprising: a burner lock-out switch and a lock-out switch actuator, control means for said combustion chamber ignition and fuel supply means, flame indication means responsive to said flame sensing means to produce a signal indicative of the flame condition in said combustion chamber, first and second switch means connected in series to complete a first energizing circuit for said lock-out switch actuator, said first switch means also being connected to said control means and adapted to latch said control means for the duration of a request for operation signal, said second switch means adapted to close and open respectively in response to no-flame and flame indications from said flame indication means, and third and fourth switch means connected in series to complete a second energizing circuit for said lock-out switch actuator, said third switch means also being connected in a trigger circuit for said first switch means and responsive to a request for operation signal to complete said trigger circuit, said fourth switch means adapted to close and open respectively in response to flame and no-flame indications from said flame indication means.

Claim 8

The burner control apparatus of claim 5, said fourth switch means in addition being connected when closed to override said trigger circuit and prevent triggering of said first switch means.

Claim 9

Burner control apparatus for use with a fuel burner installation having a combustion chamber, means to apply a request for burner operation signal to the burner control apparatus, combustion chamber ignition and fuel supply means, and flame sensing means for sensing the presence of flame in the combustion chamber, comprising: a burner lock-out switch and a lock-out switch actuator, control means for said combustion chamber ignition and fuel supply means, a first circuit responsive to the combination of a request for operation signal and a no-flame indication signal from said flame sensing means to complete energizing circuits for said lock-out switch actuator and said control means, said first circuit including a solid state Latchable means connected to latch a completed control means energizing circuit for the duration of a request for operation signal, a second circuit responsive to the combination of a request for operation signal and a flame indication signal from said flame sensing means to complete an energizing circuit for said lock-out switch actuator, and said latchable means being coupled with said second circuit to latchably override a request for operation signal applied thereto and thereby inhibit completion by said second circuit of an energizing circuit for said lock-out switch actuator, whereby said second circuit is enabled to complete an energizing circuit for said lock-out switch actuator in response to a request for operation signal only when said request for operation signal is preceded by said flame indication signal.

Claim 10

Burner control apparatus for use with a fuel burner installation having a combustion chamber, means to apply a request for burner operation signal to the burner control apparatus, combustion chamber ignition and fuel supply means, and flame sensing means for sensing the presence of flame in the combustion chamber, comprising: a burner lock-out switch and a lock-out switch actuator, control means for said combustion chamber ignition and fuel supply means, a first circuit responsive to the combination of a request for operation signal and a no-flame indication signal from said flame sensing means to complete energizing circuits for said lock-out switch actuator and said control means, said first circuit including a solid state Latchable means connected to latch a completed control means energizing circuit for the duration of a request for operation signal, a second circuit responsive to the combination of a request for operation signal and a flame indication signal from said flame sensing means to complete an energizing circuit for said lock-out switch actuator, and said latchable means being coupled with said second circuit to latchably override a request for operation signal applied thereto and thereby inhibit completion by said second circuit of an energizing circuit for said lock-out switch actuator, whereby said second circuit is enabled to complete an energizing circuit for said lock-out switch actuator in response to a request for operation signal only when said request for operation signal is preceded by said flame indication signal.

Claim 11

The burner control apparatus of claim 7, including a trigger circuit for said latchable means coupling said second circuit and said latchable means, said trigger circuit being actuable in response to the combination of a request for operation signal and said no-flame indication signal.

Claim 12

The burner control apparatus of claim 8, wherein said second circuit includes flame indication signal responsive means to override said trigger circuit and prevent triggering of said latchable means.

Claim 13

Burner control apparatus for use with a fuel burner installation having a combustion chamber, means to apply a request for burner operation signal to the burner control apparatus, combustion chamber ignition and fuel supply means, and flame sensing means for sensing the pressure of flame in the combustion chamber, comprising: an input terminal to receive a request for burner operation signal, a burner lock-out switch and a lock-out actuator, said actuator connected to said input terminal for energization by a request for burner operation signal, control means for said combustion chamber ignition and fuel supply means, connected for energization to said input terminal, flame indication means responsive to said flame sensing means to produce a signal indicative of the flame condition in said combustion chamber, a silicon controlled rectifier connected with its anode-cathode circuit in a first energizing circuit for said lock-out actuator in series with said lock-out actuator, a latching circuit connected to the anode of said silicon controlled rectifier and adapted to apply a latching signal thereto from said input terminal for the duration of a request for operation signal, first and second switching transistors connected with their collector-emitter circuits in series in a second energizing circuit for said lock-out actuator, said first switching transistor connected for gating in response to a request for operation signal at said input terminal, said second switching transistor connected to said flame indication means for gating in response to a flame signal, a voltage divider circuit connected in series with the collector-emitter circuit of said first switching transistor, said voltage divider circuit adapted to provide a trigger signal to the gate of said silicon controlled rectifier in response to gating of said first switching transistor, the anode-cathode circuit of said silicon controlled rectifier in addition being connected in a grounding circuit between the base of said first switching transistor and ground potential, whereby said silicon controlled rectifier when conductive completes said grounding circuit to remove a gating signal from said first switching transistor and reset said first switching transistor in a non-conductive mode.

Claim 14

Burner control apparatus for use with a fuel burner installation having a combustion chamber, means to apply a request for burner operation signal to the burner control apparatus, combustion chamber ignition and fuel supply means, and flame sensing means for sensing the pressure of flame in the combustion chamber, comprising: an input terminal to receive a request for burner operation signal, a burner lock-out switch and a lock-out actuator, said actuator connected to said input terminal for energization by a request for burner operation signal, control means for said combustion chamber ignition and fuel supply means, connected for energization to said input terminal, flame indication means responsive to said flame sensing means to produce a signal indicative of the flame condition in said combustion chamber, a silicon controlled rectifier connected with its anode-cathode circuit in a first energizing circuit for said lock-out actuator in series with said lock-out actuator, a latching circuit connected to the anode of said silicon controlled rectifier and adapted to apply a latching signal thereto from said input terminal for the duration of a request for operation signal, first and second switching transistors connected with their collector-emitter circuits in series in a second energizing circuit for said lock-out actuator, said first switching transistor connected for gating in response to a request for operation signal at said input terminal, said second switching transistor connected to said flame indication means for gating in response to a flame signal, a voltage divider circuit connected in series with the collector-emitter circuit of said first switching transistor, said voltage divider circuit adapted to provide a trigger signal to the gate of said silicon controlled rectifier in response to gating of said first switching transistor, the anode-cathode circuit of said silicon controlled rectifier in addition being connected in a grounding circuit between the base of said first switching transistor and ground potential, whereby said silicon controlled rectifier when conductive completes said grounding circuit to remove a gating signal from said first switching transistor and reset said first switching transistor in a non-conductive mode.

Claim 15

The burner control apparatus of claim 10, wherein said second switching transistor is connected in a low impedance ground circuit bridging said voltage divider circuit, whereby the voltage across said voltage divider circuit is restrained to a non-triggering level for said silicon controlled rectifier during conduction of said second switching transistor.

Claim 16

The burner control apparatus of claim 10, and further including an additional switching transistor in said first energizing circuit in series with the anode-cathode circuit of said silicon controlled rectifier, said additional switching transistor connected to said flame indication means to be gated in response to a no-flame signal and thereby enable completion of said first energizing circuit when said silicon controlled rectifier is conductive.

Claim 17

The burner control apparatus of claim 10, wherein the anode-cathode circuit of said silicon controlled rectifier is connected in series with said control means in said latching circuit for said silicon controlled rectifier.