US4755730A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable resistance output motor controller
Assignee: HEAT-TIMER Corp A CORP OF DE
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Filing: 1987-12-04
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Granted: 1988-07-05
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Expires: 2007-12-04
Abstract
Abstract In a thermostatic control system a solid state motor controller is provided by reproducing a potentiometer tracking with a CPU producing appropriate complimentary square wave signals having the duty cycle thereof proportional to a sensed temperature. The square wave signals are fed to circuits which are disposed across two output resistors and the effective resistance of the two resistors are varied in response to the duty cycle.
Inventors
- 👤 David Sandelman
- 👤 Douglas J. Lionetti
- 👤 Daniel E. Shprecher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 02:06
CPC Classifications
H; H02; H02P; H02P23/00; H02P23/16; Y; Y10; Y10S; Y10S388/00; Y10S388/923; Y10S388/933; Y10S388/934
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
142 words
In a control system having a motor controller and a motor controlled by the motor controller for controlling the value of a sensed parameter in response to a change in the same, the improvement wherein the motor controller comprises: first and second output resistors connected in series; one motor control output terminal at the juncture of the two output resistors and a respective second motor control output terminal at the other ends of the two output resistors; means responsive to the sensed parameter for producing a periodic control signal having a duty cycle responsive to the control action required to change the controlled parameter; and first and second means respectively connected in parallel and with the first and second resistors and responsive to the control signal for varying the effective resistance between the one output terminal and the other two output terminals.
Claim 2
Dependent Claim
142 words
In a control system having a motor controller and a motor controlled by the motor controller for controlling the value of a sensed parameter in response to a change in the same, the improvement wherein the motor controller comprises: first and second output resistors connected in series; one motor control output terminal at the juncture of the two output resistors and a respective second motor control output terminal at the other ends of the two output resistors; means responsive to the sensed parameter for producing a periodic control signal having a duty cycle responsive to the control action required to change the controlled parameter; and first and second means respectively connected in parallel and with the first and second resistors and responsive to the control signal for varying the effective resistance between the one output terminal and the other two output terminals.
Claim 3
Dependent Claim
31 words
The system according to claim 1, wherein the control signal producing means comprises means for producing the control signal and its inverse for applying to the first and second means respectively.
Claim 4
Dependent Claim
130 words
In a thermostatic control system having a motor controller and a motor controlled by the motor controller for controlling heat in response to a desired change in temperature, the improvement wherein the motor controller comprises: first and second output resistors connected in series; one motor control output terminal at the junction of the two output resistors and two motor control output terminals at the other ends of the two output resistors; means responsive to a sensed temperature for producing a periodic control signal having a duty cycle responsive to the sensed temperature; and first and second means connected in parallel with the first and second output resistors respectively and responsive to the control signal for varying the effective resistance between the one output terminal and the other two output terminals.
Claim 5
Dependent Claim
130 words
In a thermostatic control system having a motor controller and a motor controlled by the motor controller for controlling heat in response to a desired change in temperature, the improvement wherein the motor controller comprises: first and second output resistors connected in series; one motor control output terminal at the junction of the two output resistors and two motor control output terminals at the other ends of the two output resistors; means responsive to a sensed temperature for producing a periodic control signal having a duty cycle responsive to the sensed temperature; and first and second means connected in parallel with the first and second output resistors respectively and responsive to the control signal for varying the effective resistance between the one output terminal and the other two output terminals.
Claim 6
Dependent Claim
14 words
The system according to claim 3, wherein the first and second means comprise relays.
Claim 7
Dependent Claim
12 words
The system according to claim 4, wherein said relays are photovoltaic relays.
Claim 8
Dependent Claim
34 words
The system according to claim 3, wherein each of the first and second means comprises a diode bridge rectifier having a switch across the input thereof and the output resistor across the output thereof.
Claim 9
Dependent Claim
59 words
The system according to claim 6, wherein the switch is a transistor switch and the first and second means each further comprise a phototransistor connected to the transistor switch for activating same to open and short the input of the diode bridge rectifier and a light emitting diode receptive of the control signal for applying light to the phototransistor.
Claim 10
Dependent Claim
30 words
The system according to claim 7, wherein control signal producing means comprises means for producing the control signal and its inverse for applying to the first and second means respectively.
Claim 11
Dependent Claim
98 words
A motor controller comprising: first and second output resistors connected in series; one motor control output terminal at the juncture of the two output resistors and two motor control output terminals at the other ends of the two output resistors; means responsive to a sensed parameter for producing a periodic control signal having a duty cycle responsive to the sensed parameter; and first and second means connected in parallel with the first and second output resistors respectively and responsive to the control signal for varying the resistance between the one output terminal and the other two output terminals.
Claim 12
Dependent Claim
98 words
A motor controller comprising: first and second output resistors connected in series; one motor control output terminal at the juncture of the two output resistors and two motor control output terminals at the other ends of the two output resistors; means responsive to a sensed parameter for producing a periodic control signal having a duty cycle responsive to the sensed parameter; and first and second means connected in parallel with the first and second output resistors respectively and responsive to the control signal for varying the resistance between the one output terminal and the other two output terminals.
Claim 13
Dependent Claim
15 words
The system according to claim 9, wherein said first and second means comprise photovoltaic relays.
Claim 14
Dependent Claim
34 words
The system according to claim 9, wherein each of the first and second means comprises a diode bridge rectifier having a switch across the input thereof and the output resistor across the output thereof.
Claim 15
Dependent Claim
59 words
The system according to claim 11, wherein the switch is a transistor switch and the first and second means each further comprises a phototransistor connected to the transistor switch for activating same to open and short the input of the diode bridge rectifier, and a light emitting diode receptive of the control signal for applying light to the phototransistor.
Claim 16
Dependent Claim
31 words
The system according to claim 12, wherein said control signal producing means comprises means for producing the control signal and its inverse for applying to the first and second means respectively.
References Cited (Backward Citations)
US4225812A
Cited
US4216421A
Cited
US4221996A
Cited
US4426604A
Cited
US4599548A
Cited
US4722669A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-07-05 | 1992-01-04 | 1992-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-07-05 | 1996-01-04 | 1996-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-07-05 | 2000-01-04 | 2000-07-05 | $7700.00 | Window Closed / Lapsed |