US4140067A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Furnace control system
Assignee: T JENSEN ASSOC Inc
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Filing: 1977-10-27
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Granted: 1979-02-20
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Expires: 1997-10-27
Abstract
Abstract A furnace control system to control burner operation of a multifuel furnace to reduce primary fuel consumption of either oil or gas of the multifuel furnace. The system controls a primary fuel to initially kindle a secondary fuel when the fire reaches a self-sustaining burning rate, the primary fuel is shut off but the burner fan continues to run to force a draft and insure complete combustion of the secondary fuel and the volatile gases. The furnace control system is utilized as original equipment manufacturer incorporated into the controls for a burner of a multifuel furnace or as a retrofit furnace control system to control the burner operation of the multifuel furnace.
Inventors
- 👤 Thomas A. Jensen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 01:55
CPC Classifications
F; F23; F23N; F23N1/00; F23N1/02; F23N1/025; F23N2237/00; F23N2237/02; F23N2237/08
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
168 words
A fuel control system to control burning of a primary and a secondary fuel in a multifuel furnace comprising: a. fuel burning chamber means in a multifuel furnace for burning a primary fuel and a secondary fuel; b. primary fuel burner for igniting fuels; c. burner fan means for introducing air into said fuel burning chamber; d. heat exchanger means in said fuel burning chamber; e. circulating fan means to transfer heat from said heat exchanger means to a surrounding environment; f. a combination fan limit control means connected to said burner fan means for controlling the supply of air to said fuel burning chamber means; g. a first relay means connected to said combination fan limit control means whereby said relay is actuated every time said combination fan limit control means is energized; and; h. lock-out means connected to said first relay means whereby said first relay means is disabled by said lock-out means after a predetermined number of energizations of said combination fan limit control means.
Claim 2
Dependent Claim
168 words
A fuel control system to control burning of a primary and a secondary fuel in a multifuel furnace comprising: a. fuel burning chamber means in a multifuel furnace for burning a primary fuel and a secondary fuel; b. primary fuel burner for igniting fuels; c. burner fan means for introducing air into said fuel burning chamber; d. heat exchanger means in said fuel burning chamber; e. circulating fan means to transfer heat from said heat exchanger means to a surrounding environment; f. a combination fan limit control means connected to said burner fan means for controlling the supply of air to said fuel burning chamber means; g. a first relay means connected to said combination fan limit control means whereby said relay is actuated every time said combination fan limit control means is energized; and; h. lock-out means connected to said first relay means whereby said first relay means is disabled by said lock-out means after a predetermined number of energizations of said combination fan limit control means.
Claim 3
Dependent Claim
16 words
The fuel control system of claim 1 wherein said first relay means is a stepping relay.
Claim 4
Dependent Claim
18 words
The fuel control system of claim 1 wherein said first relay means is a six position stepping relay.
Claim 5
Dependent Claim
18 words
The fuel control system of claim 1 wherein said first relay means is a twelve position stepping relay.
Claim 6
Dependent Claim
19 words
The fuel control system of claim 1 wherein said predetermined number is six to lock-out said first relay means.
Claim 7
Dependent Claim
37 words
The fuel control system of claim 1 wherein said lock-out means comprises a second relay means connected to first relay means whereby said second relay means disables said first relay means after said predetermined number is reached.
Claim 8
Dependent Claim
16 words
The fuel control system of claim 6 wherein said second relay means has normally closed contacts.
Claim 9
Dependent Claim
35 words
The fuel control system of claim 8 further comprising a third relay means connected to said second relay means whereby said third relay means closes a primary fuel valve after a predetermined temperature is reached.
Claim 10
Dependent Claim
16 words
The fuel control system of claim 8 wherein said third relay means has normally open contacts.
Claim 11
Dependent Claim
41 words
The fuel control system of claim 9 further comprising a fourth relay means connected to said second relay means whereby said fourth relay means in series with a primary fuel pressure switch disables a cadmium cell in said primary fuel burner.
Claim 12
Dependent Claim
16 words
The fuel control system of claim 10, wherein said fourth relay means has normally open contacts.
References Cited (Backward Citations)
US1858450A
Cited
US2176009A
Cited
US2848958A
Cited
US3223074A
Cited
US3702594A
Cited
US4024378A
Cited
US4047515A
Cited
US4078541A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-02-19 | 1982-08-21 | 1983-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-19 | 1986-08-21 | 1987-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-19 | 1990-08-21 | 1991-02-20 | $7700.00 | Window Closed / Lapsed |