US3753356A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Means and method for determining the liquid refrigerant charge in a refrigeration system
Assignee: Ardco Inc
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Filing: 1972-05-08
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Granted: 1973-08-21
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Expires: 1992-05-08
Abstract
Abstract Dual sight glass system in the liquid line of a refrigerant circuit. One of the two sight glasses is disposed in the line at a receiver inlet and is inspected to determine the presence of liquid refrigerant in excess of the proper maximum amount. The second sight glass is disposed at the receiver outlet and is inspected to determine whether the liquid refrigerant in the system is insufficient. The latter device and its operation are known by themselves. The refrigerant circuit is hermetically sealed.
Inventors
- 👤 D Kramer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 05:53
CPC Classifications
F; F25; F25B; F25B41/00; F25B41/006; F25B43/00; F25B43/006
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
84 words
Apparatus for indicating the liquid refrigerant charge in the refrigerant circuit of a refrigeration or air conditioning system of the type having a condenser and expansion means, comprising: a hermetically closed, refrigerant containing structure; first and second sight glass units each providing means for visually observing a flow of fluid through the same, and tubing means for bringing a liquid refrigerant stream discharged from the condenser consecutively through the first sight glass, the said structure, and the second sight glass, to the expansion means.
Claim 2
Dependent Claim
84 words
Apparatus for indicating the liquid refrigerant charge in the refrigerant circuit of a refrigeration or air conditioning system of the type having a condenser and expansion means, comprising: a hermetically closed, refrigerant containing structure; first and second sight glass units each providing means for visually observing a flow of fluid through the same, and tubing means for bringing a liquid refrigerant stream discharged from the condenser consecutively through the first sight glass, the said structure, and the second sight glass, to the expansion means.
Claim 3
Dependent Claim
12 words
Apparatus as claimed in claim 1, wherein said structure is a receiver.
Claim 4
Dependent Claim
13 words
Apparatus as claimed in claim 1, wherein said structure is a filter dryer.
Claim 5
Dependent Claim
13 words
Apparatus as claimed in claim 1, wherein said structure is a liquid subcooler.
Claim 6
Dependent Claim
34 words
Apparatus as claimed in claim 1, wherein said structure is a horizontally elongated tank tilted toward one end, the portion of said tubing connecting to the expansion means being connected to said one end.
Claim 7
Independent Claim
76 words
A method of determining the liquid refrigerant charge in a hemetically closed refrigerant circuit of a refrigeration or air conditioning system which has, in sequence, a condenser, a liquid refrigerant containing structure, and an expansion means, said method comprising: visually observing the condition of any fluid entering said structure to note a possible overcharge of liquid refrigerant; and visually observing the condition of any fluid leaving said structure to note a possible undercharge of liquid refrigerant.
Claim 8
Independent Claim
76 words
A method of determining the liquid refrigerant charge in a hemetically closed refrigerant circuit of a refrigeration or air conditioning system which has, in sequence, a condenser, a liquid refrigerant containing structure, and an expansion means, said method comprising: visually observing the condition of any fluid entering said structure to note a possible overcharge of liquid refrigerant; and visually observing the condition of any fluid leaving said structure to note a possible undercharge of liquid refrigerant.
Claim 9
Independent Claim
59 words
A method of determining the liquid refrigerant charge in a hermetically closed refrigerant circuit which has, in sequence, a condenser, a liquid refrigerant containing structure, and an expansion means, said method comprising: observing whether bubbling liquid enters said structure, to avoid an overcharge of refrigerant; and observing whether clear liquid leaves said structure, to avoid an undercharge of refrigerant.
Claim 10
Independent Claim
59 words
A method of determining the liquid refrigerant charge in a hermetically closed refrigerant circuit which has, in sequence, a condenser, a liquid refrigerant containing structure, and an expansion means, said method comprising: observing whether bubbling liquid enters said structure, to avoid an overcharge of refrigerant; and observing whether clear liquid leaves said structure, to avoid an undercharge of refrigerant.
Claim 11
Independent Claim
66 words
A method of avoiding an overcharge of refrigerant in a refrigerant circuit which has, in sequence, a condenser, a liquid refrigerant containing structure, and an expansion means, said method including: observing the condition of fluid, entering said structure, to determine an overcharge of refrigerant by a clear conditon of said fluid and to determine the absence of such overcharge by a bubbling condition of said fluid.
Claim 12
Independent Claim
66 words
A method of avoiding an overcharge of refrigerant in a refrigerant circuit which has, in sequence, a condenser, a liquid refrigerant containing structure, and an expansion means, said method including: observing the condition of fluid, entering said structure, to determine an overcharge of refrigerant by a clear conditon of said fluid and to determine the absence of such overcharge by a bubbling condition of said fluid.
References Cited (Backward Citations)
US2325657A
Cited
US2608301A
Cited
US2844026A
Cited
US3177929A
Cited
US3150498A
Cited
US3108566A
Cited
US3225555A
Cited
US3545227A
Cited
US3525231A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-20 | 1977-02-19 | 1977-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-20 | 1981-02-19 | 1981-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-20 | 1985-02-19 | 1985-08-21 | $7700.00 | Window Closed / Lapsed |