US3819960A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Controller circuit
Assignee: LOVE CONTROLS CORP
•
Filing: 1973-01-26
•
Granted: 1974-06-25
•
Expires: 1993-01-26
Abstract
Abstract An improved controller that provides features, such as signal summing after amplification of the error signal, thereby minimizing adverse noise effects utilizing full scale amplification to enable analog display of the monitored parameter and conversion of a normal signal. The amplified error signal may be treated by a rate circuit to reduce lag problems. One of the amplifier stages includes feedback to provide proportioning output control through a solid state driver circuit that offers features, such as zero cross over detection, full cycle operation and excellent switching resolution. The novel circuitry provides a signal that is used in conjunction with the summed signal to provide automatic reset. The set point control accurately tracks the non-linear response characteristic of the sensing means such as thermocouples to provide a virtually errorless set point control signal to the summing circuit. A second set point control signal controls processes such as cooling, in addition to heating.
Inventors
- 👤 M Kohn
- 👤 A Alton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:15
CPC Classifications
G; G01; G01K; G01K7/00; G01K7/02; G01K7/021; G05; G05D; G05D23/00; G05D23/19; G05D23/1906; G05D23/1913; G05D23/20; G05D23/22
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
181 words
A controller for controlling the temperature at remote locations in a closed loop system, said controller comprising: switch means for energizing temperature varying equipment to vary the temperature at the remote locations, sensor means for supplying sensor signals that are functions of the temperatures at the remote locations, signal treatment means for supplying error signals responsive to the sensor signals, control signal source means for supplying control signals to cause the temperatures at the remote locations to reach desired levels, said control signal source means including set point siGnal source means for setting the desired temperature levels to a set point, means for summing the control signals and the error signals to obtain summed signals, amplifying means attached to said signal treatment means for amplifying said error signal prior to summing said control signals and said error signals, operational amplifier means operated responsive to the summed signals for providing output signals, and driver means operated responsive to said output signals to control the operation of said switch means to vary the temperatures at said remote locations to obtain said desired levels.
Claim 2
Dependent Claim
181 words
A controller for controlling the temperature at remote locations in a closed loop system, said controller comprising: switch means for energizing temperature varying equipment to vary the temperature at the remote locations, sensor means for supplying sensor signals that are functions of the temperatures at the remote locations, signal treatment means for supplying error signals responsive to the sensor signals, control signal source means for supplying control signals to cause the temperatures at the remote locations to reach desired levels, said control signal source means including set point siGnal source means for setting the desired temperature levels to a set point, means for summing the control signals and the error signals to obtain summed signals, amplifying means attached to said signal treatment means for amplifying said error signal prior to summing said control signals and said error signals, operational amplifier means operated responsive to the summed signals for providing output signals, and driver means operated responsive to said output signals to control the operation of said switch means to vary the temperatures at said remote locations to obtain said desired levels.
Claim 3
Dependent Claim
114 words
The controller of claim 1 wherein said amplifying means comprises differential amplifier means, said signal treatment means comprising a bridge circuit, said sensor means comprising thermocouple means having one end connected to a midpoint of one leg of the bridge circuit and the other end connected to one input of said differential amplifier, means for coupling the other input of said differential amplifier means to the midpoint of the other leg of said bridge, and a first amplifier means attached to the output of said differential amplifier means for further amplifying said error signals prior to the summing of said error signals and said control signals and, said first amplifier means providing impedance transformation.
Claim 4
Dependent Claim
109 words
The controller of claim 1 wherein the output signals of said operational amplifier means cycles on and off within a temperature band about the set point with a proportionally varying on-to-off time per cycle and with the output being entirely on below the band and entirely off above the band, whereby said output is in the form of a square wave signal within the band, said closed loop system having a stable point which may be offset from said set point, and said control signal source means further including reset signal source means for automatically providing reset signals to reset said stable point to conform to said set point.
Claim 5
Dependent Claim
71 words
The controller of claim 3 wherein said automatic reset signal source comprises window detector means attached to said differential amplifier means for determining when the temperature at said remote location is slightly above or slightly below said proportional band, clamping means attached to said window detector means for preventing the reset signals from being applied to said summing means unless said temperature at said remote location is within said proportional band.
Claim 6
Dependent Claim
100 words
The controller of claim 4 wherein said automatic reset signal source means comprises reset integrator means for measuring the on-to-off time proportion of said operational amplifier means output signals, said reset integrator means comprising a resistor capacitor network connected to the output of said operational amplifier, analog amplifier means coupled to said resistor capacitor net-work, and the output of said analog amplifier means being connected to said summing means to provide an automatic reset signal to vary the square wave output of said operational amplifier means as a function of any offset of said stable point from said set point.
Claim 7
Dependent Claim
95 words
The controller of claim 3 wherein said driver means includes trigger means operating responsive to the simultaneous receipt of a synchronous alternating current signal and the operational amplifier output on signals, said operational amplifier output signals cycling on and off within a temperature band with a proportional varying on-to-off time within the band, said output signal being on below the band and off above the band, and means responsive to the operation of said trigger means for providing energization pulses extending over substantially a complete cycle of said alternating current for energizing the switching devices.
Claim 8
Dependent Claim
74 words
The controller of claim 6 wherein said trigger means comprises means for providing square wave signals, differentiating means for differentiating said square wave signals, one shot multi-vibrator means operated responsive to said differentiated square wave signal, oscillator means operated responsive to the output of said one shot multi-vibrator means to provide the energization signals, and said one shot multi-vibrator means including a recovery circuit for speeding the recovery of said one shot multi-vibrator means.
Claim 9
Dependent Claim
13 words
The controller of claim 7 wherein said oscillator means comprises blocking oscillator means.
Claim 10
Dependent Claim
72 words
The controller of claim 1 wherein said control signal producing means includes first and second set point signal sources, second means for summing said amplified error signals and said control signals being connected to said second set point signal sources to provdie second summed signals, second operational amplifier means operated responsive to the second summed signals, and second driver means operated responsive to the output signal of said second operational amplifier means.
Claim 11
Dependent Claim
30 words
The controller of claim 9 wherein said second set point control signal is used for operating a cooling apparatus, and means for assuring fast turn off of said cooling apparatus.
Claim 12
Dependent Claim
101 words
The controller of claim 10 wherein timed negative feedback means are provided for said second operational amplifier means, said feedback means comprising a voltage divider network, timing network means connected between said voltage divider network and the inverting input of said second operational amplifier means, said timing network means comprising first and second series resistors, a feedback timing capacitor connected between the junction of said series resistors and ground, and means responsive to an output signal from said second operational amplifier means for turning on said cooling apparatus to couple an oppositely charged capacitor in parallel with said feedback timing capacitor.
Claim 13
Dependent Claim
94 words
The controller of claim 1 wherein feedback circuit means are provided for causing the output of said operational amplifier to cycle on and off, temperature band proximate to said set point so that the output signal is a square wave being a duty cycle with 0% on above the band and 100 percent on below the band with a proportional duty cycle within the band, said feedback circuit comprising a series resistor network connecting the output of the operational amplifier to the output and feedback capacitor means extending from said resistor network to ground.
Claim 14
Dependent Claim
184 words
A controller for controlling the temperature at remote locations in a closed loop system, said controller comprising: switch means for energizing temperature varying equipment to vary the temperature at the remote locations, sensor means for supplying sensor signals that are functions of the temperatures at the remote locations, signal treatment means for supplying error signals responsive to the sensor signals, control signal source means for supplying control signals to cause the temperatures at the remote locations to reach desired levels, means for summing the cntrol signals and the error signals to obtain summed signals, rate circuit means for receiving said error signals prior to said error signal being summed at said control signal, said rate circuit means comprising inactive elements said control signal source means including set point signal source means for setting the desired temperature levels to set point, operational amplifier means operated responsive to the summed signals for providing output signals, and driver means operated responsive to said output signals to control the operation of said switch means to vary the temperatures at said remote locations to obtain said desired temperature levels.
Claim 15
Dependent Claim
184 words
A controller for controlling the temperature at remote locations in a closed loop system, said controller comprising: switch means for energizing temperature varying equipment to vary the temperature at the remote locations, sensor means for supplying sensor signals that are functions of the temperatures at the remote locations, signal treatment means for supplying error signals responsive to the sensor signals, control signal source means for supplying control signals to cause the temperatures at the remote locations to reach desired levels, means for summing the cntrol signals and the error signals to obtain summed signals, rate circuit means for receiving said error signals prior to said error signal being summed at said control signal, said rate circuit means comprising inactive elements said control signal source means including set point signal source means for setting the desired temperature levels to set point, operational amplifier means operated responsive to the summed signals for providing output signals, and driver means operated responsive to said output signals to control the operation of said switch means to vary the temperatures at said remote locations to obtain said desired temperature levels.
Claim 16
Dependent Claim
67 words
The controller of claim 13 wherein the output of said amplifying means is connected to rate circuit means, said rate circuit means comprising a first capacitor in parallel with the first resistor, said parallel combination of said first Capacitor and first resistor connected in series with a second resistor, and said second resistor being connected to the means for summing the control signals and the error signals.
Claim 17
Dependent Claim
192 words
A controller for controlling the temperature at remote locations in a closed loop system, said controller comprising: switch means for energizing temperature varying equipment to vary the temperature at the remote locations, signal treatment means for supplying error signals responsive to the sensor signals, control signal source means for supplying control signals to cause the temperatures at the remote locations to reach desired levels, said control signal source means including set point signal source means for setting the desired temperature levels to a set point, said set point signal source means comprising constant current source means, digital switch means coupled to said constant current source means to provide set point signals that are functions of the resistance of said digital switch means, said digital switch means simulating the characteristic curve of said sensor means, means for summing the control signals and the error signals to obtain summed signals, operational amplifier means operated responsive to the summed signals for providing output signals, and driver means operated responsive to said output signals to control the operation of said switch means to vary the temperatures at said remote locations to obtain said desired temperature levels.
Claim 18
Dependent Claim
192 words
A controller for controlling the temperature at remote locations in a closed loop system, said controller comprising: switch means for energizing temperature varying equipment to vary the temperature at the remote locations, signal treatment means for supplying error signals responsive to the sensor signals, control signal source means for supplying control signals to cause the temperatures at the remote locations to reach desired levels, said control signal source means including set point signal source means for setting the desired temperature levels to a set point, said set point signal source means comprising constant current source means, digital switch means coupled to said constant current source means to provide set point signals that are functions of the resistance of said digital switch means, said digital switch means simulating the characteristic curve of said sensor means, means for summing the control signals and the error signals to obtain summed signals, operational amplifier means operated responsive to the summed signals for providing output signals, and driver means operated responsive to said output signals to control the operation of said switch means to vary the temperatures at said remote locations to obtain said desired temperature levels.
Claim 19
Dependent Claim
19 words
The controller of claim 15 wherein said digital switch means is connected to provide positive or negative set points.
Claim 20
Dependent Claim
56 words
The controller of claim 16 wherein safety means are provided to detect certain deviations from the normal otuput of said constant current source, and means responsive to the detection of said deviations for changing the output of said set point signal source to prevent failure of the closed loop system if said digital switch means opens.
Claim 21
Dependent Claim
166 words
A controller comprising a source of electrical power, thermocouple means, operational amplifier means connected to said source and to said thermocouple means and responsive to said thermocouple means for manifesting a first output signal when the temperature of said thermocouple means is below a predetermined limit, and a second output signal when the temperature of said thermocouple means is above said predetermined limit, sensing means connected to said source of power for sensing a restoration of power after an interruption thereof, means for connecting said sensing means with said operational amplifier means for forcing said operational amplifier means to manifest said first output signal for a predetermined interval following said restoration, amplifying means for amplifying the signals from said thermocouple means, control signal source means for providing signals to set the controller to provide a desired temperature at said thermocouple means, and means for summing said control signals and the amplified signals from said thermocouple means connected between said amplifying means and said operational amplifier means.
Claim 22
Dependent Claim
166 words
A controller comprising a source of electrical power, thermocouple means, operational amplifier means connected to said source and to said thermocouple means and responsive to said thermocouple means for manifesting a first output signal when the temperature of said thermocouple means is below a predetermined limit, and a second output signal when the temperature of said thermocouple means is above said predetermined limit, sensing means connected to said source of power for sensing a restoration of power after an interruption thereof, means for connecting said sensing means with said operational amplifier means for forcing said operational amplifier means to manifest said first output signal for a predetermined interval following said restoration, amplifying means for amplifying the signals from said thermocouple means, control signal source means for providing signals to set the controller to provide a desired temperature at said thermocouple means, and means for summing said control signals and the amplified signals from said thermocouple means connected between said amplifying means and said operational amplifier means.
Claim 23
Dependent Claim
33 words
The controller of claim 18 and rate circuit means coupled to operate on said error signal between said amplifier means and said operational amplifier, and the components of said rate circuit being passive.
Claim 24
Dependent Claim
57 words
The controller of claim 18 including set point signal source means for providing a set point signal to cause the temperature at the location of the sensor to reach and maintain a set point, said set point signal source comprising constant current means and two terminal digital resistor means for simulating the characteristic curve of the sensor.
Claim 25
Dependent Claim
171 words
A controller comprising sensing means for producing an electrical signal in response to the value of a physical parameter, the controller having an output terminal, proportional signal generating means connected to said sensing means and responsive to said electrical signal for producing a proportional signal at said output terminal, said proportional signal having a duty cycle related to the deviation of the sensed level of said parameter from a preselected level over a given range of said parameter, said proportional signal generating means comprising an operational amplifier, a first voltage divider connected to the output of said operational amplfiier, negative feedback means connecting said first voltage divider to the inverting input of said amplifier for supplying negative feedback to said amplifier, a second voltage divider connected with the output of said operational amplifier, means for connecting said second voltage divider to the non-inverting input of said operational amplifier to supply positive feedback to said operational amplifier, and capacitor means connected between said negative feedback means and a source of reference potential.
Claim 26
Dependent Claim
171 words
A controller comprising sensing means for producing an electrical signal in response to the value of a physical parameter, the controller having an output terminal, proportional signal generating means connected to said sensing means and responsive to said electrical signal for producing a proportional signal at said output terminal, said proportional signal having a duty cycle related to the deviation of the sensed level of said parameter from a preselected level over a given range of said parameter, said proportional signal generating means comprising an operational amplifier, a first voltage divider connected to the output of said operational amplfiier, negative feedback means connecting said first voltage divider to the inverting input of said amplifier for supplying negative feedback to said amplifier, a second voltage divider connected with the output of said operational amplifier, means for connecting said second voltage divider to the non-inverting input of said operational amplifier to supply positive feedback to said operational amplifier, and capacitor means connected between said negative feedback means and a source of reference potential.
Claim 27
Dependent Claim
66 words
The controller of claim 21 including first amplifier means connected to said sensing means for providing an amplified error signal, control signal source means for providing control signals to control the output signal to cause said physical parameter to reach and maintain a set point, and summing means for summing said amplified error signals and said control signals between said amplifier means and said operational amplifier.
Claim 28
Dependent Claim
20 words
The controller of claim 22 wherein passive rate circuit means are provided between said amplifier means and said summing means.
Claim 29
Dependent Claim
35 words
The controller of claim 22 wherein said control signal source means comprises constant current source means, digital switch means coupled to said constant current source means to simulate the characteristic curve of said sensing means.
Claim 30
Dependent Claim
43 words
The controller of claim 22 wherein said control signal source means comprises automatic reset signal source means for providing a signal to reset any offset between a stable parameter reached under the control of the controller and the set point of control signals.
Claim 31
Dependent Claim
25 words
The controller of claim 25 and means for preventing a reset signal when the error signal is not within the given range of said parameter.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-24 | 1977-12-24 | 1978-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-24 | 1981-12-24 | 1982-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-24 | 1985-12-24 | 1986-06-25 | $7700.00 | Window Closed / Lapsed |