US4470272A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hermetically circulating, absorption type refrigerator
Assignee: Hitachi Ltd
•
Filing: 1982-08-26
•
Granted: 1984-09-11
•
Expires: 2002-08-26
Abstract
Abstract In a hermetically circulating, absorption type refrigerator based on a closed circulation system of constituent members comprised of a successive communication of a regenerator, a condenser, an evaporator, an absorber and a heat exchanger, refrigeration being produced by repetitions of concentration, refrigerant dilution, and heat exchange of an aqueous concentrated lithium bromide solution sealed in the circulation system, the aqueous concentrated lithium bromide solution contains at least one each of (a) an inhibitor having a boiling point higher than the solution temperature in the regenerator and (b) an inhibitor having a boiling point lower than the solution temperature in the regenerator. Corrosion of metallic materials used in a refrigerant circulation loop of the refrigerator and those in the absorbing solution circulation loop can be effectively prevented.
Inventors
- 👤 Masahiko Itoh
- 👤 Heihatiro Midorikawa
- 👤 Akira Minato
- 👤 Kenzi Machizawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:38
CPC Classifications
F; F25; F25B; F25B47/00; F25B47/003; F25B15/00; F25B15/008; F25B15/02; F25B15/06; Y; Y02; Y02A; Y02A30/00; Y02A30/27; Y02B; Y02B30/00; Y02B30/62
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
166 words
A hermetically circulating, absorption type refrigerator having metallic elements providing a refrigerant circulation loop comprises of a condenser and an evaporator containing water as a refrigerant and a closed circulation system comprised of a successive communication of a regenerator, the condenser, the evaporator, an absorber and a heat exchanger, refrigeration being produced by repetitions of concentration, refrigerant dilution, and heat exchange of an aqueous concentrated lithium bromide solution as an absorbing solution sealed in the circulation system, the improvement wherein said aqueous concentrated lithium bromide solution contains at least one each of (a) an inhibitor which has a boiling point higher than the solution temperature in the regenerator and which is an inorganic chromate, molybdate, nitrate, nitrite, tungstate, borate, silicate or phosphate, ruthenium chloride, benztriazole, tolyltriazole, 1,3-diethyl-2-thiourea, thiosinamine, sodium thioxyanate, diphenyl thiocarbazide, or 1-acetyl-2-thiourea and (b) an inhibitor which has a boiling point lower than the solution temperature in the regenerator and which is morpholine, pyrrolidine, 2-methylpyrrolidine, 3-methylpyrrolidine, piperidine, 2-methylpiperidine, hexamethyleneimide, mercaptoacetic acid, thiazole or isothiazole.
Claim 2
Dependent Claim
166 words
A hermetically circulating, absorption type refrigerator having metallic elements providing a refrigerant circulation loop comprises of a condenser and an evaporator containing water as a refrigerant and a closed circulation system comprised of a successive communication of a regenerator, the condenser, the evaporator, an absorber and a heat exchanger, refrigeration being produced by repetitions of concentration, refrigerant dilution, and heat exchange of an aqueous concentrated lithium bromide solution as an absorbing solution sealed in the circulation system, the improvement wherein said aqueous concentrated lithium bromide solution contains at least one each of (a) an inhibitor which has a boiling point higher than the solution temperature in the regenerator and which is an inorganic chromate, molybdate, nitrate, nitrite, tungstate, borate, silicate or phosphate, ruthenium chloride, benztriazole, tolyltriazole, 1,3-diethyl-2-thiourea, thiosinamine, sodium thioxyanate, diphenyl thiocarbazide, or 1-acetyl-2-thiourea and (b) an inhibitor which has a boiling point lower than the solution temperature in the regenerator and which is morpholine, pyrrolidine, 2-methylpyrrolidine, 3-methylpyrrolidine, piperidine, 2-methylpiperidine, hexamethyleneimide, mercaptoacetic acid, thiazole or isothiazole.
Claim 3
Dependent Claim
20 words
The hermetically circulating, absorption type refrigerator according to claim 1, wherein the inhibitor having a low boiling point is morpholine.
Claim 4
Dependent Claim
38 words
The hermetically circulating, absorption type refrigerator according to claim 1, wherein the aqueous absorbing solution contains sodium molybdate and benztriazole as the inhibitor having a high boiling point and morpholine as the inhibitor having a low boiling point.
Claim 5
Dependent Claim
27 words
The hermetically circulating, absorption type refrigerator according to claim 1, wherein the lithium bromide solution contains the low-boiling inhibitor at a concentration of 100 ppm by weight.
Claim 6
Dependent Claim
40 words
The hermetically circulating, absorption type refrigerator according to claim 1, wherein the aqueous absorbing solution contains 0.03-0.05% by weight of morpholine, pyrrolidine, piperidine or 2-methylpiperidine or 0.05 to 0.08% by weight of mercaptoacetic acid or isothiazole as the low-boiling inhibitor.
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) | 1987-09-11 | 1988-03-12 | 1988-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-11 | 1992-03-12 | 1992-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-11 | 1996-03-12 | 1996-09-11 | $7700.00 | Window Closed / Lapsed |