US3826100A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for controlling freezing apparatus
Assignee: Individual
•
Filing: 1972-05-19
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Granted: 1974-07-30
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Expires: 1992-05-19
Abstract
Abstract Method and apparatus for optimum recovery of an evaporating coolant in a direct contact type of freezing apparatus, such method including measuring the differential pressure in the supply or discharge duct to or from the freezing chamber and the pressure of the air in the space in which the apparatus is located resulting from the diffusion of coolant and air within the apparatus and using the pressure difference to control the discharge of air from the apparatus.
Inventors
- 👤 L Vahl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:23
CPC Classifications
A; A23; A23B; A23B2/00; A23B2/80; A23B2/803; A23B2/8033; F; F25; F25D; F25D29/00; F25D29/001
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
150 words
A method for controlling apparatus for freezing watercontaining substances, such as food, by contacting the substances directly with an evaporating coolant, wherein said apparatus includes a freezing chamber in which said evaporation takes place, duct means into which the substances enter and leave the freezing chamber and by which the freezing chamber is directly opened to the aTmosphere, a condensation chamber for recovering and recycling excess coolant and condensed evaporated coolant, and means for discharging air cooled by the condensation chamber from the freezing chamber to the atmosphere, the improvement comprising the steps of: measuring the difference in pressure between the ambient atmosphere and one of the duct means due to diffusion of coolant and air in the freezing chamber; producing a control signal indicative of said difference in pressure; and controlling the operation of the freezing apparatus in response to said control signal to improve recovery of the coolant.
Claim 2
Independent Claim
150 words
A method for controlling apparatus for freezing watercontaining substances, such as food, by contacting the substances directly with an evaporating coolant, wherein said apparatus includes a freezing chamber in which said evaporation takes place, duct means into which the substances enter and leave the freezing chamber and by which the freezing chamber is directly opened to the aTmosphere, a condensation chamber for recovering and recycling excess coolant and condensed evaporated coolant, and means for discharging air cooled by the condensation chamber from the freezing chamber to the atmosphere, the improvement comprising the steps of: measuring the difference in pressure between the ambient atmosphere and one of the duct means due to diffusion of coolant and air in the freezing chamber; producing a control signal indicative of said difference in pressure; and controlling the operation of the freezing apparatus in response to said control signal to improve recovery of the coolant.
Claim 3
Dependent Claim
28 words
The method of claim 1 wherein said control signal is used to control the discharge, through said discharge means, of the amount of air in said freezing apparatus.
Claim 4
Dependent Claim
19 words
The method of claim 2, wherein the discharge through said discharge means is accomplished by an adjustable suction pump.
Claim 5
Dependent Claim
37 words
The method of claim 2, wherein the discharge through said discharge means is accomplished by a downcomer which is filled with a cold air-coolant mixture and allows the cold air to gravitationally escape into the ambient atmosphere.
Claim 6
Dependent Claim
26 words
The method of claim 1 wherein said control signal operates on control means for controlling the rate of condensation of coolant evaporating in said freezing chamber.
Claim 7
Dependent Claim
51 words
The method of claim 5 wherein said control means is a control valve located between said freezing chamber and said condensation chamber, said control valve opening further as said difference of pressure exceeds a predetermined value and said control valve throttling when said difference of pressure falls below said predetermined value.
Claim 8
Dependent Claim
28 words
The method of claim 5, wherein operation of said control means is accomplished by operating a control valve located between said condensation chamber and said air discharge means.
Claim 9
Independent Claim
144 words
An apparatus for freezing water-containing substances, such as food, wherein the apparatus includes a freezing chamber in which freezing occurs by directly contacting the substances to be frozen with an evaporating coolant, duct means through which the water-containing substances enter and leave the freezing chamber and through which the freezing chamber is opened to the atmosphere, a condensation chamber for recovering and recycling excess coolant and means for discharging air cooled by said condensation chamber from the freezing chamber to the atmosphere, wherein the improvement comprises: means for measuring the difference in pressure between the ambient atmosphere and one of the duct means resulting from diffusion of coolant and air; means for producing a control signal indicative of the difference in pressure; and means for controlling operation of the freezing apparatus in response to said control signal to thereby improve recovery of the coolant.
Claim 10
Independent Claim
144 words
An apparatus for freezing water-containing substances, such as food, wherein the apparatus includes a freezing chamber in which freezing occurs by directly contacting the substances to be frozen with an evaporating coolant, duct means through which the water-containing substances enter and leave the freezing chamber and through which the freezing chamber is opened to the atmosphere, a condensation chamber for recovering and recycling excess coolant and means for discharging air cooled by said condensation chamber from the freezing chamber to the atmosphere, wherein the improvement comprises: means for measuring the difference in pressure between the ambient atmosphere and one of the duct means resulting from diffusion of coolant and air; means for producing a control signal indicative of the difference in pressure; and means for controlling operation of the freezing apparatus in response to said control signal to thereby improve recovery of the coolant.
Claim 11
Dependent Claim
15 words
The freezing apparatus of claim 8 wherein said discharge means is an adjustable suction pump.
Claim 12
Dependent Claim
19 words
The freezing apparatus of claim 8 wherein said discharge means is a downcomer filled with a cold air-coolant mixture.
Claim 13
Dependent Claim
52 words
The freezing apparatus of claim 8 wherein said control means is a control valve located between said freezing chamber and said condensation chamber, said control valve opening further as said difference of pressure exceeds a predetermined value and said control valve throttling when said difference of pressure falls below said predetermined value.
Claim 14
Dependent Claim
37 words
The freezing apparatus of claim 8 wherein said control means is a control valve located between said condensation chamber and said air discharge means, said control valve closing when said difference of pressure exceeds a predetermined value.
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) | 1977-07-29 | 1978-01-28 | 1978-07-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-29 | 1982-01-28 | 1982-07-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-29 | 1986-01-28 | 1986-07-30 | $7700.00 | Window Closed / Lapsed |