US3922527A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Temperature control apparatus
Assignee: National Forge Co
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Filing: 1974-12-26
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Granted: 1975-11-25
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Expires: 1994-12-26
Abstract
Abstract The disclosed invention describes an apparatus and method for bringing a system having high interactive portions to a predetermined temperature distribution. The invention includes a difference controller which provides, through two separate drivers, a fixed total amount of energy to the system being controlled. If the system being controlled also has a long cycle time, second and third temperature controllers may be used to bring the system to the equilibrium temperature with a minimum amount of overshoot. The invention is particularly advantageous when used in connection with a high pressure, high temperature vessel useful in growing quartz crystals.
Inventors
- 👤 Donald E Witkin
- 👤 Arnold G Bowles
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 01:50
CPC Classifications
C; C30; C30B; C30B29/00; C30B29/10; C30B29/16; C30B29/18; C30B7/00; C30B7/10; G; G05; G05D; G05D23/00; G05D23/19; G05D23/1927; G05D23/193; G05D23/1932; G05D23/1934; G05D23/20; G05D23/22; Y; Y10; Y10T; Y10T117/00; Y10T117/10; Y10T117/1004; Y10T117/1008; Y10T117/1024; Y10T117/1096
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
150 words
A temperature control apparatus for controlling a differential temperature between at least two locations in a system comprising a first temperature sensing means for providing an output indicative of temperature at a first location, a second temperature sensing means for providing an output indicative of temperature at a second location, a temperature controller for providing an output signal responsive to the outputs of both the first and second temperature sensing means, driver means responsive to the output signal of the temperature controller for applying a first variable amount of energy to a first heater element associated with said first location and for applying a second variable amount of energy to a second heater element associated with the second location, and said driver means having a total energy output to said first and second heater elements which is substantially independent of the value of the output signal from the temperature controller.
Claim 2
Dependent Claim
150 words
A temperature control apparatus for controlling a differential temperature between at least two locations in a system comprising a first temperature sensing means for providing an output indicative of temperature at a first location, a second temperature sensing means for providing an output indicative of temperature at a second location, a temperature controller for providing an output signal responsive to the outputs of both the first and second temperature sensing means, driver means responsive to the output signal of the temperature controller for applying a first variable amount of energy to a first heater element associated with said first location and for applying a second variable amount of energy to a second heater element associated with the second location, and said driver means having a total energy output to said first and second heater elements which is substantially independent of the value of the output signal from the temperature controller.
Claim 3
Dependent Claim
27 words
The temperature control apparatus of claim 1 wherein said temperature controller is responsive to the difference in temperatures sensed by said first and second temperature sensing means.
Claim 4
Dependent Claim
63 words
The temperature control apparatus of claim 2 wherein said driver means includes a first driver responsive to the output signal of the temperature controller for applying said first variable amount of energy to said first heater element, and a second driver responsive to the output signal of the temperature controller for applying said second variable amount of energy to said second heater element.
Claim 5
Dependent Claim
31 words
The temperature control apparatus of claim 3 wherein said first and second temperature sensing means are thermocouples and the total energy applied to said first and second heater elements is constant.
Claim 6
Dependent Claim
29 words
The temperature control apparatus of claim 3 wherein the energy output of each of said first and second drivers is proportional to the output signal of the temperature controller.
Claim 7
Dependent Claim
91 words
The temperature control apparatus of claim 2 including a second temperature controller for providing an output signal responsive to the output of said first temperature sensing means, a third driver responsive to the output signal of said second temperature controller for providing output energy to a third heater element associated with said first location, and said second controller having a set point offset at an end of a proportional band for said controllEr at which energy applied to said second heater is significantly below the maximum output for the third driver.
Claim 8
Dependent Claim
18 words
The temperature control apparatus of claim 6 wherein said second controller has a high gain and no reset.
Claim 9
Dependent Claim
106 words
The temperature control apparatus of claim 6 including a third temperature controller having a signal output responsive to the temperature sensed at one of said two locations, a fourth driver responsive to the signal output of said third temperature controller for applying energy to a fourth heater element associated with said second location, said third temperature controller and said fourth driver applying a first predetermined energy when the temperature at said one location is below a predetermined value and a second predetermined energy when the temperature at said one location is above said predetermined value, said second predetermined energy being less than said first predetermined energy.
Claim 10
Dependent Claim
21 words
The temperature control apparatus of claim 8 including means associated with said first location for introducing heat loss into the system.
Claim 11
Dependent Claim
217 words
A temperature control apparatus for bringing to a desired temperature equilibrium a system having a large thermal time lag comprising a temperature sensing means for providing an output indicative of the temperature of the system, a first temperature controller for providing an output signal responsive to the output of said temperature sensing means, a first driver responsive to said output signal of said controller for applying energy to a first heater for heating said system, said temperature controller having a set point offset near a high end of a proportional band for said controller whereby at equilibrium the energy applied to said first heater is significantly less than a maximum output energy of the first driver, a second controller for providing a second output signal responsive to the temperature of said system, said second signal having a first value when said temperature is below a predetermined level and a second value when said temperature is above said predetermined level, and a second driver for applying a first amount of energy to a second heater element in response to the first value of said second signal and a second amount of energy to said second heater in response to the second value of said signal, said second amount of energy being less than said first amount of energy.
Claim 12
Dependent Claim
217 words
A temperature control apparatus for bringing to a desired temperature equilibrium a system having a large thermal time lag comprising a temperature sensing means for providing an output indicative of the temperature of the system, a first temperature controller for providing an output signal responsive to the output of said temperature sensing means, a first driver responsive to said output signal of said controller for applying energy to a first heater for heating said system, said temperature controller having a set point offset near a high end of a proportional band for said controller whereby at equilibrium the energy applied to said first heater is significantly less than a maximum output energy of the first driver, a second controller for providing a second output signal responsive to the temperature of said system, said second signal having a first value when said temperature is below a predetermined level and a second value when said temperature is above said predetermined level, and a second driver for applying a first amount of energy to a second heater element in response to the first value of said second signal and a second amount of energy to said second heater in response to the second value of said signal, said second amount of energy being less than said first amount of energy.
Claim 13
Dependent Claim
27 words
The temperature control apparatus of claim 10 including means to introduce heat loss into said system and said first controller having a high gain and no reset.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-24 | 1979-05-26 | 1979-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-24 | 1983-05-26 | 1983-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-24 | 1987-05-26 | 1987-11-25 | $7700.00 | Window Closed / Lapsed |