US3634699A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Condition-responsive control circuit
Assignee: Owens Corning
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Filing: 1970-03-03
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Granted: 1972-01-11
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Expires: 1990-03-03
Abstract
Abstract Apparatus for generating a signal for controlling a condition, such as liquid level, which may fall above, within or below a predetermined tolerance range. One of two switches is closed when the condition is out of tolerance in one direction and the other switch is closed when the condition is out of tolerance in the other direction. Closure of one switch charges a capacitor, while closure of the other switch discharges the capacitor. The state of charge on the capacitor, which is dependent upon the time and the direction in which the condition is out of tolerance, is maintained constant when both switches are open. The charge on the capacitor is applied to the gate of a field-effect transistor, which generates a control signal for bringing the condition within the tolerance range. The apparatus is particularly suitable for controlling the level of a pool of molten glass in an orificed feeder for forming glass fibers or filaments.
Inventors
- 👤 Melvin R Cox
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:38
CPC Classifications
G; G01; G01F; G01F23/00; G01F23/14; G01F23/16; G01F23/165; G01F23/168; G05; G05D; G05D9/00; G05D9/12
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
102 words
Apparatus for generating a signal for controlling a condition which may fall below, within or above a predetermined tolerance range comprising, in combination, a capacitor, means for exponentially charging said capacitor when the condition is out of tolerance in one direction, means for exponentially discharging said capacitor when the condition is out of tolerance in the other direction, the charge on said capacitor remaining substantially constant when the condition is within the tolerance range, and valve means having a high impedance gate terminal connected to said capacitor for generating a control signal which is a function of the charge on said capacitor.
Claim 2
Dependent Claim
102 words
Apparatus for generating a signal for controlling a condition which may fall below, within or above a predetermined tolerance range comprising, in combination, a capacitor, means for exponentially charging said capacitor when the condition is out of tolerance in one direction, means for exponentially discharging said capacitor when the condition is out of tolerance in the other direction, the charge on said capacitor remaining substantially constant when the condition is within the tolerance range, and valve means having a high impedance gate terminal connected to said capacitor for generating a control signal which is a function of the charge on said capacitor.
Claim 3
Dependent Claim
51 words
Apparatus for generating a signal for controlling a condition, as defined in claim l, wherein said valve means comprises a field-effect transistor having gate, source and drain electrodes, and means connecting said capacitor between said gate and said source electrodes, the control signal appearing between said source and said drain electrodes.
Claim 4
Dependent Claim
132 words
Apparatus for generating a signal for controlling a condition which may fall below, within or above a predetermined tolerance range comprising, in combination, first and second switches, means for closing said first switch when the condition is above the tolerance range, means for closing said second switch when the condition is below the tolerance range, said first and second switches both being open when the condition is within the tolerance rAnge, a capacitor, means for exponentially charging said capacitor when one of said switches is closed, means for exponentially discharging said capacitor when the other of said switches is closed, the charge on said capacitor remaining substantially constant when both of said switches are open, and means for generating a control signal which is a function of the charge on said capacitor.
Claim 5
Dependent Claim
132 words
Apparatus for generating a signal for controlling a condition which may fall below, within or above a predetermined tolerance range comprising, in combination, first and second switches, means for closing said first switch when the condition is above the tolerance range, means for closing said second switch when the condition is below the tolerance range, said first and second switches both being open when the condition is within the tolerance rAnge, a capacitor, means for exponentially charging said capacitor when one of said switches is closed, means for exponentially discharging said capacitor when the other of said switches is closed, the charge on said capacitor remaining substantially constant when both of said switches are open, and means for generating a control signal which is a function of the charge on said capacitor.
Claim 6
Dependent Claim
55 words
Apparatus for generating a signal for controlling a condition, as defined in claim 3, wherein said means for generating a control signal comprises a field-effect transistor having gate, source and drain electrodes, and means connecting said capacitor between said gate and said source electrodes, the control signal appearing between said source and said drain electrodes.
Claim 7
Dependent Claim
72 words
Apparatus for generating a signal for controlling a condition, as defined in claim 3, wherein said means for exponentially charging said capacitor includes a source of direct current, a resistor and means connecting said one switch, said source, said resistor and said capacitor in series, and wherein said means for exponentially discharging said capacitor includes a second resistor and means connecting said other switch, said second resistor and said capacitor in series.
Claim 8
Dependent Claim
55 words
Apparatus for generating a signal for controlling a condition, as defined in claim 5, wherein said means for generating a control signal comprises a field-effect transistor having gate, source and drain electrodes, and means connecting said capacitor between said gate and said source electrodes, the control signal appearing between said source and said drain electrodes.
Claim 9
Dependent Claim
162 words
In apparatus of forming glass filaments and including an orificed feeder for holding a pool of molten glass from which glass filaments are drawn and a glass premelter for delivering a stream of molten glass to the feeder, apparatus for controlling the surface level of the pool of molten glass in the feeder comprising, in combination, a capacitor, means for exponentially charging said capacitor when the surface level is out of a predetermined tolerance range in one direction, means for exponentially discharging said capacitor when the surface level is out of the tolerance range in an opposite direction, the charge on said capacitor remaining substantially constant when the surface level is within the predetermined tolerance range, valve means having a high-impedance gate terminal connected to said capacitor for generating a control signal which is a function of the charge on said capacitor, and means responsive to such control signal for controlling the stream of molten glass from the premelter to the feeder.
Claim 10
Dependent Claim
162 words
In apparatus of forming glass filaments and including an orificed feeder for holding a pool of molten glass from which glass filaments are drawn and a glass premelter for delivering a stream of molten glass to the feeder, apparatus for controlling the surface level of the pool of molten glass in the feeder comprising, in combination, a capacitor, means for exponentially charging said capacitor when the surface level is out of a predetermined tolerance range in one direction, means for exponentially discharging said capacitor when the surface level is out of the tolerance range in an opposite direction, the charge on said capacitor remaining substantially constant when the surface level is within the predetermined tolerance range, valve means having a high-impedance gate terminal connected to said capacitor for generating a control signal which is a function of the charge on said capacitor, and means responsive to such control signal for controlling the stream of molten glass from the premelter to the feeder.
Claim 11
Dependent Claim
126 words
Apparatus for controlling the surface level of a pool of molten glass in an orificed feeder for forming glass filaments, as defined in claim 7, wherein said means for exponentially charging said capacitor includes a first switch, a resistor, a source of direct current, means connecting said first switch, and said source, said resistor and said capacitor in series, and means for closing said first switch when the surface level is out of tolerance in the one direction, and wherein said means for exponentially discharging said capacitor includes a second switch, a second resistor, means connecting said second switch, said second resistor and said capacitor in series, and means for closing said second switch when the surface level is out of tolerance in the opposite direction.
Claim 12
Dependent Claim
67 words
Apparatus for controlling the surface level of a pool of molten glass in an orificed feeder for forming glass filaments, as defined in claim 8, wherein said valve means for generating a control signal comprises a field-effect transistor having gate, source and drain electrodes, and means connecting said capacitor between said gate and said source electrodes, the control signal appearing between said source and said drain electrodes.
Claim 13
Dependent Claim
92 words
Apparatus for controlling the surface level of a pool of molten glass in an orificed feeder for forming glass filaments, as defined in claim 8, wherein said means for controlling the stream of molten glass from the premelter to the feeder comprises means for electrically heating said premelter, and means responsive to such control signal for increasing current to said electrically heating means when the surface level is below the predetermined tolerance range and for decreasing current to said electrical heating means when the surface level is above the predetermined tolerance range.
Claim 14
Dependent Claim
147 words
Apparatus for controlling the surface level of a pool of molten glass in an orificed feeder for forming glass filaments, as defined in claim 8, wherein said first switch is pressure responsive and is closed when an applied pressure exceeds a first predetermined pressure, said second switch is pressure responsive and is closed when an applied pressure is below a second predetermined pressure less than said first pressure, and wherein said means for closing said first switch and said means for closing said second switch comprises a hollow probe having a gas discharge end positioned within the feeder below the surface of the pool of molten glass, means for supplying a constant flow of gas to said probe, the pressure of such gas varying with the surface level of the pool of molten glass, and means for applying the gas pressure to said first and second switches.
Claim 15
Dependent Claim
146 words
Apparatus for controlling the surface level of a pool of molten glass in an orificed feeder for forming glass filaments, as defined in claim 8, wherein said first switch is pressure responsive and is closed when an applied pressure is below a first predetermined pressure, said second switch is pressure responsive and is closed when an applied pressure exceeds a second pressure greater than said first pressure, and wherein said means for closing said first switch and said means for closing said second switch comprises a hollow probe having a gas discharge end positioned within the feeder below the surface of the pool of molten glass, means for supplying a constant flow of gas to said probe, the pressure of such gas varying with the surface level of the pool of molten glass, and means for applying the gas pressure to said first and second switches.
Claim 16
Dependent Claim
126 words
Apparatus for controlling the surface level of a pool of liquid in a container as liquid is removed from the container comprising, in combination, a capacitor, means for exponentially charging said capacitor when the liquid surface level is out of a predetermined tolerance range in one direction, means for exponentially discharging said capacitor when the liquid surface level is out of the tolerance range in an opposite direction, the charge on said capacitor remaining substantially constant when the surface level is within the predetermined tolerance range, valve means having a high-impedance gate terminal connected to said capacitor for generating a control signal which is a function of the charge on said capacitor, and means responsive to such control signal for supplying additional liquid to the container.
Claim 17
Dependent Claim
126 words
Apparatus for controlling the surface level of a pool of liquid in a container as liquid is removed from the container comprising, in combination, a capacitor, means for exponentially charging said capacitor when the liquid surface level is out of a predetermined tolerance range in one direction, means for exponentially discharging said capacitor when the liquid surface level is out of the tolerance range in an opposite direction, the charge on said capacitor remaining substantially constant when the surface level is within the predetermined tolerance range, valve means having a high-impedance gate terminal connected to said capacitor for generating a control signal which is a function of the charge on said capacitor, and means responsive to such control signal for supplying additional liquid to the container.
Claim 18
Dependent Claim
128 words
Apparatus for controlling the surface level of a pool of liquid in a container, as defined in claim 13, wherein said means for exponentially charging said capacitor includes a first switch, a resistor, a source of direct current, means connecting said first switch, said source, said resistor and said capacitor in series, and means for closing said first switch when the surface level is out of tolerance in the one direction; wherein said means for exponentially discharging said capacitor includes a second switch, a second resistor, means connecting said second switch, said second resistor and said capacitor in series, and means for closing said second switch when the surface level is out of tolerance in the opposite direction; and wherein said valve means comprises a field effect transistor.
Claim 19
Dependent Claim
107 words
Apparatus for generating a signal for controlling a condition which may fall below, within or above a predetermined tolerance range comprising, in combination, an energy storage device, means for increasing the energy stored in said device when the condition is out of tolerance in one direction, means for decreasing the energy stored in said device when the condition is out of tolerance in the other direction, the stored energy in said device remaining substantially constant when the condition is within the tolerance range, and means connected to said energy storage device for generating a control signal which is a function of the energy stored in said device.
Claim 20
Dependent Claim
107 words
Apparatus for generating a signal for controlling a condition which may fall below, within or above a predetermined tolerance range comprising, in combination, an energy storage device, means for increasing the energy stored in said device when the condition is out of tolerance in one direction, means for decreasing the energy stored in said device when the condition is out of tolerance in the other direction, the stored energy in said device remaining substantially constant when the condition is within the tolerance range, and means connected to said energy storage device for generating a control signal which is a function of the energy stored in said device.
Claim 21
Dependent Claim
129 words
Apparatus for controlling the surface level of a pool of liquid in a container as liquid is removed from the container comprising, in combination, an energy storage device, means for increasing the energy stored in said device when the surface level is out of a predetermined tolerance range in one direction, means for decreasing the energy stored in said device when the surface level is out of the tolerance range in the other direction, the stored energy in said device remaining substantially constant when the surface level is within the tolerance range, means connected to said energy storage device for generating a control signal which is a function of the energy stored in said device, and means responsive to the control signal for supplying additional liquid to the container.
Claim 22
Dependent Claim
129 words
Apparatus for controlling the surface level of a pool of liquid in a container as liquid is removed from the container comprising, in combination, an energy storage device, means for increasing the energy stored in said device when the surface level is out of a predetermined tolerance range in one direction, means for decreasing the energy stored in said device when the surface level is out of the tolerance range in the other direction, the stored energy in said device remaining substantially constant when the surface level is within the tolerance range, means connected to said energy storage device for generating a control signal which is a function of the energy stored in said device, and means responsive to the control signal for supplying additional liquid to the container.
Claim 23
Dependent Claim
132 words
Apparatus for controlling the surface level of a pool of molten glass in a container as molten glass is continuously removed from the container compromising, in combination, an energy storage device, means for increasing the energy stored in said device when the surface level is out of a predetermined tolerance range in one direction, means for decreasing the energy stored in said device when the surface level is out of the tolerance range in the other direction, the stored energy in said device remaining substantially constant when the surface level is within the tolerance range, means connected to said energy storage device for generating a control signal which is a function of the energy stored in said device, and means responsive to the control signal for supplying additional glass to the container.
Claim 24
Dependent Claim
132 words
Apparatus for controlling the surface level of a pool of molten glass in a container as molten glass is continuously removed from the container compromising, in combination, an energy storage device, means for increasing the energy stored in said device when the surface level is out of a predetermined tolerance range in one direction, means for decreasing the energy stored in said device when the surface level is out of the tolerance range in the other direction, the stored energy in said device remaining substantially constant when the surface level is within the tolerance range, means connected to said energy storage device for generating a control signal which is a function of the energy stored in said device, and means responsive to the control signal for supplying additional glass to the container.
Claim 25
Dependent Claim
52 words
Apparatus for controlling the surface level of a pool of molten glass in a container, as defined in claim 17, wherein said energy storage device is a capacitor, and wherein said means for generating a control signal includes a field effect transistor having a high impedance gate terminal connected to said capacitor.
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) | 1975-01-10 | 1975-07-12 | 1976-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-10 | 1979-07-12 | 1980-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-10 | 1983-07-12 | 1984-01-11 | $7700.00 | Window Closed / Lapsed |