US3815813A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hot water heating system
Assignee: Saunier Duval SA
•
Filing: 1972-05-26
•
Granted: 1974-06-11
•
Expires: 1992-05-26
Abstract
Abstract In the hot water heating system disclosed herein, a sensing means such as a thermistor provides a first electrical control signal which represents deviation of outlet water temperature from preselected value and a flowmeter provides a pulsating electrical signal having a frequency which varies as a function of rate of flow through the heating system. An output signal is generated having a frequency equal to that of the pulsating signal and a squarewave pulse duration which varies as a function of the first control signal. Heater means are then energized by the output signal so as to provide a thermal input to the heating system which is substantially proportional to the product of water output temperature deviation and flow rate. This control minimizes output temperature fluctuations due to thermal inertia and heater lag.
Inventors
- 👤 J Charron
- 👤 F Sagnard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:12
CPC Classifications
F; F24; F24D; F24D19/00; F24D19/10; F24D19/1006; F24D19/1066; F24D19/1069; F23; F23N; F23N5/00; F23N5/02; F24H; F24H15/00; F24H15/10; F24H15/174; F24H15/175; F24H15/20; F24H15/212; F24H15/219; F24H15/238; F24H15/30; F24H15/305; F24H15/31; F24H9/00; F24H9/20; F24H9/2007; F24H9/2035; G; G01; G01K; G01K17/00; G01K17/06; G01K17/08; G01K17/10; G01K17/12; G01K17/16; G05; G05D; G05D23/00; G05D23/19; G05D7/00; G05D7/06; G05D7/0617; F23N2227/00; F23N2227/10; F24H15/355; F24H15/37
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
125 words
A hot water heating system comprising: sensing means for generating an electrical signal which varies as a function of the deviation of outlet water temperature from a preselected temperature; a flowmeter providing a pulsating electrical signal having a frequency which varies as a function of the rate of water flow through the heating system; means interconnected with and responsive to said sensing means and said flowmeter for generating a squarewave output signal having a frequency equal to said pulsating signal and a squarewave duration which varies as a function of said temperature deviation; and heater means controlled by said squarewave output signal for providing a thermal input to said heating system which is substantially proportional to the product of said deviation and said flow rate.
Claim 2
Dependent Claim
125 words
A hot water heating system comprising: sensing means for generating an electrical signal which varies as a function of the deviation of outlet water temperature from a preselected temperature; a flowmeter providing a pulsating electrical signal having a frequency which varies as a function of the rate of water flow through the heating system; means interconnected with and responsive to said sensing means and said flowmeter for generating a squarewave output signal having a frequency equal to said pulsating signal and a squarewave duration which varies as a function of said temperature deviation; and heater means controlled by said squarewave output signal for providing a thermal input to said heating system which is substantially proportional to the product of said deviation and said flow rate.
Claim 3
Dependent Claim
31 words
A hot water heating system as set forth in claim 1 wherein said sensing means includes a thermistor for providing an electrical signal which varies as a function of outlet temperature.
Claim 4
Dependent Claim
39 words
A hot water heating system as set forth in claim 2 further comprising means providing a reference signal representing said preselected temperature and means for combining said outlet temperature signal and said reference signal to obtain said deviation signal.
Claim 5
Dependent Claim
41 words
A hot water heating system as set forth in claim 1 wherein said heater means includes a gas burner and control means comprising a valve providing a proportionally variable flow of gas responsive to a pulse width modulated squarewave control signal.
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) | 1977-06-10 | 1977-12-10 | 1978-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-10 | 1981-12-10 | 1982-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-10 | 1985-12-10 | 1986-06-11 | $7700.00 | Window Closed / Lapsed |