US3589846A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Burner control system
Assignee: Therm O Disc Inc
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Filing: 1970-03-23
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Granted: 1971-06-29
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Expires: 1990-03-23
Abstract
Abstract A burner ignition and control system including two solenoid valves connected in series between the fuel supply and burner. An electrical resistance-type ignitor is provided to cause ignition and a sensor determines when the ignitor is in ignition condition and when combustion occurs properly. The circuit is arranged to provide automatic recycling when combustion does not occur or is prematurely terminated. A delay is provided when recycling occurs during which the burner and related system is purged of unburned fuel or products of combustion. The sensor is an ambient temperature compensated device operated by a bimetallic element to sense the rate of radiant heat emission from the ignitor and burner. The sensor is not directly exposed to the high temperature conditions at the ignitor and in the combustion zone so a simple bimetallic element is directly connected to operate the sensor switch.
Inventors
- 👤 Donald E Place
- 👤 Donald J Schmitt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:44
CPC Classifications
F; F23; F23N; F23N5/00; F23N5/02; F23N5/04; F23N5/045; F23N5/20; F23N5/206; F23N2227/00; F23N2227/04; F23N2227/38; F23N2233/00; F23N2233/06
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
158 words
A burner control system comprising a burner, a pair of solenoid valves connected in series with said burner operable to supply fuel to said burner only when both valves are open, intermittently operable igniter means, sensing means provided with switching means, and circuit means connecting said switch means with said solenoid valves and said igniter means, said sensing means and said circuit means being arranged to produce a cycle of operation each time ignition is required in which one of said valves is opened only when said sensing means determine that flame is not present and said igniter means are not in an ignition condition and thereafter opening said second of said valves only when said sensing means determine that said igniter is in an ignition condition, said sensing means and circuit means operating to cause said valves to terminate fuel flow when ignition does not occur within a predetermined interval after the flow of fuel is initiated.
Claim 2
Dependent Claim
158 words
A burner control system comprising a burner, a pair of solenoid valves connected in series with said burner operable to supply fuel to said burner only when both valves are open, intermittently operable igniter means, sensing means provided with switching means, and circuit means connecting said switch means with said solenoid valves and said igniter means, said sensing means and said circuit means being arranged to produce a cycle of operation each time ignition is required in which one of said valves is opened only when said sensing means determine that flame is not present and said igniter means are not in an ignition condition and thereafter opening said second of said valves only when said sensing means determine that said igniter is in an ignition condition, said sensing means and circuit means operating to cause said valves to terminate fuel flow when ignition does not occur within a predetermined interval after the flow of fuel is initiated.
Claim 3
Dependent Claim
38 words
A burner control system as set forth in claim 1 wherein a fan is provided which operates continuously when said circuit means are energized to evacuate unburned fuel or products of combustion from the area of said burner.
Claim 4
Dependent Claim
36 words
A burner control system as set forth in claim 2 wherein power is supplied to said control systems through switch means associated with said fan to power said circuit means only when said fan is operating.
Claim 5
Dependent Claim
31 words
A burner control system as set forth in claim 2 wherein said control system provides a purging delay during which said fan operates before fuel can be supplied to said burner.
Claim 6
Dependent Claim
49 words
A burner control system as set forth in claim 4 wherein said igniter means is an electrical resistance heating device with sufficient thermal mass to provide a heating delay before it reaches a temperature sufficiently high to operate said sensing means, and said heating delay provides said purging delay.
Claim 7
Dependent Claim
91 words
A burner control system as set forth in claim 1 wherein said igniter means is an electrical heating device operable when supplied with rated voltage to reach a temperature above ignition temperature, and said circuit continues to supply a low voltage below said rated voltage to said igniter means while combustion continues, said low voltage being sufficient to maintain said igniter means at a low temperature above ambient temperature and below ignition temperature, said sensing means initiating opening of said second valve only when said igniter means is above ignition temperature.
Claim 8
Dependent Claim
28 words
A burner control system as set forth in claim 6 wherein rated voltage is supplied to said igniter only when at least one of said valves is closed.
Claim 9
Dependent Claim
46 words
A burner control system as set forth in claim 1 wherein said igniter emits radiant heat at a rate which is a direct function of its temperature, and said sensing means are sensitive to and operate in response to the rate of emission of radiant heat.
Claim 10
Dependent Claim
37 words
A burner control system as set forth in claim 8 wherein said sensing means are located so that conductive and convective flow of heat from said burner and igniter means to said sensing means is relatively insignificant.
Claim 11
Dependent Claim
22 words
A burner control system as set forth in claim 8 wherein said sensing means are substantially insensitive to convective and conductive heat.
Claim 12
Dependent Claim
22 words
A burner control system as set forth in claim 8 wherein said sensing means are substantially unaffected by changes in ambient temperature.
Claim 13
Dependent Claim
77 words
A burner control system as set forth in claim 1 wherein said sensing means include support means, a bimetallic element providing at least two substantially parallel legs joined at one end, the other end of a first of said legs being supported by said support means, a switching contact carried by the other end of the second of said legs, said support means providing radiant energy communication between said igniter means and only one of said legs.
Claim 14
Dependent Claim
26 words
A burner control system as set forth in claim 12 wherein said support means provide radiant energy communication between said igniter means and said first leg.
Claim 15
Dependent Claim
161 words
A burner control system comprising a burner, a source of fluid fuel, first and second normally closed solenoid valves connected in series between said source and burner, an electrically operable resistance-type igniter, sensor means including a normally closed sensor switch operable to determine when said igniter is in condition to cause ignition and open said sensor switch, a holding switch connected so that it is in a first position when said first valve is closed and in a second position when said first valve is open, and a pair of power lines adapted to be supplied with line voltage, said second valve being connected in parallel with said sensor switch and being connected across said line in series with said igniter, and said first valve being connected across said lines in series with said sensor switch when said holding switch is in said first position and being connected across said lines directly when said holding switch is in said second position.
Claim 16
Dependent Claim
161 words
A burner control system comprising a burner, a source of fluid fuel, first and second normally closed solenoid valves connected in series between said source and burner, an electrically operable resistance-type igniter, sensor means including a normally closed sensor switch operable to determine when said igniter is in condition to cause ignition and open said sensor switch, a holding switch connected so that it is in a first position when said first valve is closed and in a second position when said first valve is open, and a pair of power lines adapted to be supplied with line voltage, said second valve being connected in parallel with said sensor switch and being connected across said line in series with said igniter, and said first valve being connected across said lines in series with said sensor switch when said holding switch is in said first position and being connected across said lines directly when said holding switch is in said second position.
Claim 17
Dependent Claim
26 words
A burner control system as set forth in claim 14 wherein said holding switch is operated by the solenoid of said first valve and provides overlap.
Claim 18
Dependent Claim
40 words
A burner control system as set forth in claim 14 wherein said igniter provides sufficient thermal mass to remain above ignition temperature for the period of time necessary for fuel to reach said burner after said valves are both open.
Claim 19
Dependent Claim
48 words
A burner control as set forth in claim 14 wherein the resistance of said second solenoid valve and the resistance of said igniter are arranged so that sufficient current is present to open said second valve when it is connected across said lines in series with said igniter.
Claim 20
Dependent Claim
41 words
A burner control system as set forth in claim 14 wherein the resistance of said two solenoid valves is arranged so that insufficient current is present to open said first valve when said valves are connected in series across said lines.
Claim 21
Dependent Claim
186 words
A burner control system comprising a burner, a source of fluid fuel, first and second normally closed solenoid valves connected in series between said source and burner, an electrically operable igniter, sensor means including a normally closed sensor switch operable to determine when said ignitor is in condition to cause ignition and open said sensor switch, a pair of power lines adapted to be supplied with electrical power, said first valve including first coil means connected in parallel with said ignitor, said valve including second coil means connected in parallel with said sensor switch, said ignitor and said first coil means being connected in series with said second coil means and said switch across said power lines when said valves are closed, and holding means operable to hold said first valve open when said seNsor switch is open, said second coil means opening said second valve only when power is applied to said power lines and said sensor switch is open, said first coil means causing said first valve to open only when power is applied to said power lines and said sensor switch is closed.
Claim 22
Dependent Claim
186 words
A burner control system comprising a burner, a source of fluid fuel, first and second normally closed solenoid valves connected in series between said source and burner, an electrically operable igniter, sensor means including a normally closed sensor switch operable to determine when said ignitor is in condition to cause ignition and open said sensor switch, a pair of power lines adapted to be supplied with electrical power, said first valve including first coil means connected in parallel with said ignitor, said valve including second coil means connected in parallel with said sensor switch, said ignitor and said first coil means being connected in series with said second coil means and said switch across said power lines when said valves are closed, and holding means operable to hold said first valve open when said seNsor switch is open, said second coil means opening said second valve only when power is applied to said power lines and said sensor switch is open, said first coil means causing said first valve to open only when power is applied to said power lines and said sensor switch is closed.
Claim 23
Dependent Claim
43 words
A burner control system as set forth in claim 19 wherein said second coil means is operable to open said second valve when a voltage is applied to said second coil means which is less than the voltage applied to said power lines.
Claim 24
Dependent Claim
45 words
A burner control system as set forth in claim 20 wherein opening of said sensor switch causes substantial drop in the voltage applied to said ignitor and causes sufficient voltage to be applied to said second coil means to cause opening to said second valve.
Claim 25
Dependent Claim
44 words
A burner control system as set forth in claim 19 wherein said ignitor is a resistance-type ignitor and provides sufficient thermal mass to remain above ignition temperatures for the period of time necessary for fuel to reach said burner after said valves are open.
Claim 26
Dependent Claim
43 words
A burner control system as set forth in claim 19 wherein said first and second coil means are arranged so that insufficient current is applied to said first coil means to cause said first valve to open when said sensor switch is open.
Claim 27
Dependent Claim
182 words
A burner control system comprising a burner, a source of fluid fuel, first and second normally closed solenoid valves connected in series between said source and burner, an electrically operated ignitor, sensor means including a normally closed sensor switch operable to determine when said ignitor is in condition to cause ignition and open said sensor switch, a pair of power lines adapted to be supplied with electrical power, said first valve including first coil means connected in series with said sensor switch, said first coil means operating to open said first valve only when power is applied to said power lines and said sensor switch is closed, said second valve including second coil means connected in parallel with said sensor switch and being shunted thereby when said sensor switch is closed, said second coil means operating to open said second valve only when power is applied to said power lines and said sensor switch is opened, and holding means operable to hold said first valve open when said sensor switch is open and power continues to be supplied to said power lines.
Claim 28
Dependent Claim
182 words
A burner control system comprising a burner, a source of fluid fuel, first and second normally closed solenoid valves connected in series between said source and burner, an electrically operated ignitor, sensor means including a normally closed sensor switch operable to determine when said ignitor is in condition to cause ignition and open said sensor switch, a pair of power lines adapted to be supplied with electrical power, said first valve including first coil means connected in series with said sensor switch, said first coil means operating to open said first valve only when power is applied to said power lines and said sensor switch is closed, said second valve including second coil means connected in parallel with said sensor switch and being shunted thereby when said sensor switch is closed, said second coil means operating to open said second valve only when power is applied to said power lines and said sensor switch is opened, and holding means operable to hold said first valve open when said sensor switch is open and power continues to be supplied to said power lines.
Claim 29
Dependent Claim
62 words
A burner control system as set forth in claim 24 wherein said ignitor is connected in series with said sensing switch and said second coil means and said ignitor is a resistance-type ignitor, the voltage applied to said ignitor when said sensing switch is open being insufficient to maintain said ignitor at a sufficiently high temperature to maintain said sensing switch open.
Claim 30
Dependent Claim
43 words
A burner control system as set forth in claim 25 wherein said second coil means is operable to open said second valve when a voltage is applied to said second coil means which is less than the voltage applied to said power lines.
Claim 31
Dependent Claim
44 words
A burner control system as set forth in claim 26 wherein said ignitor is a resistance-type ignitor and provides sufficient thermal mass to remain above ignition temperatures for the period of time necessary for fuel to reach said burner after said valves are open.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-28 | 1974-12-28 | 1975-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-28 | 1978-12-28 | 1979-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-28 | 1982-12-28 | 1983-06-29 | $7700.00 | Window Closed / Lapsed |