US3725644A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Input switch for reversing the sense of an amplifier in a single loop heating-cooking system
Assignee: Schneider Electric Buildings Americas Inc
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Filing: 1972-04-11
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Granted: 1973-04-03
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Expires: 1992-04-11
Abstract
Abstract A single-pole, double-throw switch and a pair of input resistors connected in series between the alternative terminals of said switch may be employed between a pair of condition sensitive terminals and a pair of input terminals for an amplifier to reverse the sense of the amplifier output.
Inventors
- 👤 R Bailey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 00:33
CPC Classifications
G; G05; G05D; G05D23/00; G05D23/19; G05D23/1927; G05D23/193; G05D23/1931; G05D23/1906; G05D23/1913; G05D23/20; G05D23/24
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
147 words
In combination, an amplifier having a pair of input terminals and an output terminal, a first input resistor, a second input resistor, one end of each of said input resistors coupled to a junction, a switching means having a common terminal selectively connected to one of a first and a second alternative terminals, said alternative terminals joined to respective other ends of said input resistors, a pair of signal terminals for coupling to respective signal sources, the other ends of said input resistors coupled to the respective terminals of one of said pairs of terminals, and the junction and said common terminal coupled to the respective terminals of the other of said pairs of terminals, whereby the sense of an output signal produced at said output terminal may be reversed by changing the connection of said common terminal from one to the other of said alternative terminals.
Claim 2
Dependent Claim
147 words
In combination, an amplifier having a pair of input terminals and an output terminal, a first input resistor, a second input resistor, one end of each of said input resistors coupled to a junction, a switching means having a common terminal selectively connected to one of a first and a second alternative terminals, said alternative terminals joined to respective other ends of said input resistors, a pair of signal terminals for coupling to respective signal sources, the other ends of said input resistors coupled to the respective terminals of one of said pairs of terminals, and the junction and said common terminal coupled to the respective terminals of the other of said pairs of terminals, whereby the sense of an output signal produced at said output terminal may be reversed by changing the connection of said common terminal from one to the other of said alternative terminals.
Claim 3
Dependent Claim
28 words
A combination according to claim 1 wherein said amplifier comprises an operational amplifier, said pair of input terminals comprising the inverting and non-inverting input terminals of said amplifier.
Claim 4
Dependent Claim
21 words
A combination according to claim 2 additionally comprising a feedback circuit between the output terminal and one of said input terminals.
Claim 5
Dependent Claim
40 words
A combination according to claim 2, wherein the pair of terminals coupled to said junction and the common terminal comprises the inverting and non-inverting input terminals, and additionally comprising a feedback resistor coupled between the output and inverting input terminals.
Claim 6
Dependent Claim
41 words
A combination according to claim 4, in which said input resistors are substantially equal, whereby the gain of said amplifier remains substantially constant as the connection of said common terminal is charged from one to The other of said alternative terminals.
Claim 7
Dependent Claim
59 words
A combination according to claim 2, wherein the inverting input terminal is coupled to said first input resistor, the non-inverting input terminal is coupled to said second input resistor, and additionally comprising a third input resistor coupled between the common terminal and one of said signal terminals, and a feedback resistor coupled between the output and inverting input terminals.
Claim 8
Dependent Claim
62 words
A combination according to claim 6, in which said first input resistor is selected to be substantially equal to the product divided by the sum of the resistances of said second and third input resistors, whereby the gain of said amplifier remains substantially constant as the connection of said common terminal is changed from one to the other of said alternative terminals.
Claim 9
Dependent Claim
16 words
A combination according to claim 1 wherein said switching means comprises a single-pole, double- throw switch.
Claim 10
Dependent Claim
34 words
A combination according to claim 1 additionally comprising operating means selectively changing the connection of said common terminal from one to the other of said alternative terminals in response to a variable sensed condition.
Claim 11
Dependent Claim
20 words
A combination according to claim 1 wherein said signal terminals comprise the output terminals of a condition sensitive impedance bridge.
Claim 12
Dependent Claim
36 words
A combination according to claim 1 wherein one of said signal terminals is connected to a source of reference voltage and the other of said signal terminals is connected to a source of condition sensitive voltage.
Claim 13
Dependent Claim
99 words
A combination according to claim 4, comprising in addition a pair of current supply lines, a temperature sensitive bridge receiving current from said supply lines and delivering a temperature responsive and a reference signal to the signal terminals, said bridge comprising a temperature sensitive resistor in a controlled space and a variable set point resistor, a conduit delivering a selected one of hot and chilled fluids to said space, an operator selectively changing the connection of said common terminal from one to the other of said alternative terminals in response to a change in the selection of said fluids.
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) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |