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US4912934A Expired / Lapsed US ⏱️ 0.0 years remaining

Hermetically closed circulation type, vapor absorption refrigerator

Assignee: Hitachi Ltd
•
Filing: 1988-10-05
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Granted: 1990-04-03
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Expires: 2008-10-05
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Abstract

Abstract A hermetically closed circulation type, vapor absorption refrigerator which comprises a high temperature regenerator, a low temperature regenerator a condenser, an evaporator, an absorber and heat exchangers in a hermetically closed circulation system as essential constituent members composed of iron-based materials, where refrigeration is produced by repetitions of concentration of an absorbing solution sealed into the circulation system, dilution with a cooling medium and heat exchange, the inside wall of the high temperature regenerator being provided with a composite film of molybdenum oxides and iron oxide can be operated stably with a high reliability or corrosion resistance.

Inventors

  • 👤 Masahiko Itoh
  • 👤 Heihatiro Midorikawa
  • 👤 Kazutoshi Itoh
  • 👤 Yasumasa Furutani
  • 👤 Michihiko Aizawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 22:57
CPC Classifications
C; C09; C09K; C09K5/00; C09K5/02; C09K5/04; C09K5/047; C23; C23C; C23C22/00; C23C22/05; C23C22/60; C23C22/62; C23F; C23F11/00; C23F11/08; F; F25; F25B; F25B15/00; F25B15/008; F25B15/02; F25B15/06; F25B47/00; F25B47/003; Y; Y10; Y10S; Y10S62/00; Y10S62/20

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 202 words
A process for forming an anti-corrosive film on the inside wall of a high temperature regenerator of a hermetically closed circulation type, vapor absorption refrigerator comprising a high temperature regenerator, a low temperature regenerator, a condenser, an evaporator, an absorber and heat exchangers in a hermetically closed circulation system as essential constituent members composed of iron-based materials, which comprises providing a solution recycle line and a cooling medium supply line to the high temperature regenerator, sealing an aqueous solution containing molybdate ions and having a pH of 7.5 to 11 as a film-forming solution into the high temperature regenerator in advance to a refrigerating operation, recycling the film-forming solution in the high temperature regenerator through the solution recycle line while heating the high temperature refrigerator and supplying a cooling medium to the high temperature regenerator in an amount to balance the amount of water vapor evaporated from the film-making solution through the cooling medium supply line, thereby subjecting the high temperature regenerator to a film-forming operation and forming an anti-corrosive film on the inside wall of the high temperature regenerator, then closing the solution recycle line and the cooling medium supply line and withdrawing the film-forming solution from the high temperature regenerator.
Claim 2
Dependent Claim 202 words
A process for forming an anti-corrosive film on the inside wall of a high temperature regenerator of a hermetically closed circulation type, vapor absorption refrigerator comprising a high temperature regenerator, a low temperature regenerator, a condenser, an evaporator, an absorber and heat exchangers in a hermetically closed circulation system as essential constituent members composed of iron-based materials, which comprises providing a solution recycle line and a cooling medium supply line to the high temperature regenerator, sealing an aqueous solution containing molybdate ions and having a pH of 7.5 to 11 as a film-forming solution into the high temperature regenerator in advance to a refrigerating operation, recycling the film-forming solution in the high temperature regenerator through the solution recycle line while heating the high temperature refrigerator and supplying a cooling medium to the high temperature regenerator in an amount to balance the amount of water vapor evaporated from the film-making solution through the cooling medium supply line, thereby subjecting the high temperature regenerator to a film-forming operation and forming an anti-corrosive film on the inside wall of the high temperature regenerator, then closing the solution recycle line and the cooling medium supply line and withdrawing the film-forming solution from the high temperature regenerator.
Claim 3
Dependent Claim 27 words
A process according to claim 1, wherein the heating of the high temperature regenerator is carried out at the boiling point or higher of the film-forming solution.
Claim 4
Dependent Claim 21 words
A process according to claim 1, wherein the anti-corrosive film is a composite oxide film of molybdenum oxides and iron oxide.
Claim 5
Dependent Claim 25 words
A process according to claim 3, wherein the composite oxide film is richer in the molybdenum oxides outwardly from the inside wall in the film.
Claim 6
Dependent Claim 25 words
A process according to claim 3, wherein the composite oxide film is richer in the iron oxide inwardly toward the inside wall in the film.
Claim 7
Dependent Claim 95 words
A process for forming an anti-corrosive film on the inside wall of a high temperature regenerator of a hermetically closed circulation type, vapor absorption refrigerator comprising a high temperature regenerator, a low temperature regenerator, a condenser, an evaporator, an absorber and heat exchangers in a hermetically closed circulation system as essential constituent members composed of iron-based materials, which comprises introducing a film-making solution into the high temperature regenerator and heating the high temperature regenerator in the presence of the film-making solution, thereby forming an anti-corrosive film on the inside wall of the high temperature regenerator.
Claim 8
Dependent Claim 95 words
A process for forming an anti-corrosive film on the inside wall of a high temperature regenerator of a hermetically closed circulation type, vapor absorption refrigerator comprising a high temperature regenerator, a low temperature regenerator, a condenser, an evaporator, an absorber and heat exchangers in a hermetically closed circulation system as essential constituent members composed of iron-based materials, which comprises introducing a film-making solution into the high temperature regenerator and heating the high temperature regenerator in the presence of the film-making solution, thereby forming an anti-corrosive film on the inside wall of the high temperature regenerator.
Claim 9
Dependent Claim 27 words
A process according to claim 6, wherein the heating of the high temperature regenerator is carried out at the boiling point or higher of the film-forming solution.
Claim 10
Dependent Claim 21 words
A process according to claim 6, wherein the anti-corrosive film is a composite oxide film of molybdenum oxides and iron oxide.
Claim 11
Dependent Claim 25 words
A process according to claim 8, wherein the composite oxide film is richer in the molybdenum oxides outwardly from the inside wall in the film.
Claim 12
Dependent Claim 25 words
A process according to claim 8, wherein the composite oxide film is richer in the iron oxide inwardly toward the inside wall in the film.
Claim 13
Dependent Claim 104 words
A hermetically closed circulation type, vapor absorption refrigerator which comprises a high temperature regenerator, a low temperature regenerator, a condenser, an evaporator, an absorber and heat exchangers in a hermetically closed circulation system as essential constituent members composed of iron-based materials, where refrigeration is produced by repetitions of concentration of an absorbing solution sealed into the circulation system, dilution with a cooling medium and heat exchange, and recycle piping being provided at the high temperature regenerator, thereby passing a film-making solution in a liquid state through the high temperature regenerator and forming an anti-corrosive film on an inside wall of the high temperature regenerator.
Claim 14
Dependent Claim 104 words
A hermetically closed circulation type, vapor absorption refrigerator which comprises a high temperature regenerator, a low temperature regenerator, a condenser, an evaporator, an absorber and heat exchangers in a hermetically closed circulation system as essential constituent members composed of iron-based materials, where refrigeration is produced by repetitions of concentration of an absorbing solution sealed into the circulation system, dilution with a cooling medium and heat exchange, and recycle piping being provided at the high temperature regenerator, thereby passing a film-making solution in a liquid state through the high temperature regenerator and forming an anti-corrosive film on an inside wall of the high temperature regenerator.
Claim 15
Dependent Claim 37 words
A hermetically closed circulation type vapor absorption refrigerator according to claim 11 wherein the anti-corrosive film is a composite oxide film richer in molybdenum oxides than in other oxides outwardly from the inside wall in the film.
Claim 16
Dependent Claim 37 words
A hermetically closed circulation type vapor absorption refrigerator according to claim 11, wherein the anti-corrosive film is a composite oxide film richer in iron oxide than in other oxides inwardly toward the inside wall of the film.
Claim 17
Dependent Claim 50 words
A hermetically closed circulation type vapor absorption refrigerator according to claim 11, wherein the absorbing solution is an aqueous lithium bromide solution containing a small amount of an alkali hydroxide and at least one of very small amounts of molybdate and nitrate and a small amount of a higher alcohol.
Claim 18
Dependent Claim 67 words
A hermetically closed circulation type, vapor absorption refrigerator according to claim 11, wherein the absorbing solution is an aqueous absorbing solution containing 50 to 70% by weight of LiBr, 0.05 to 1.0% by weight of LiOH, 10 to 150 ppm of Li 2 MoO 4 as MoO 4 2- , and 5 to 350 ppm of LiNO 3 as NO 3 - , the balance being water.
Claim 19
Dependent Claim 63 words
A hermetically closed circulation type, vapor absorption refrigerator according to claim 11, wherein the absorbing solution is an aqueous absorbing solution containing 50 to 70% by weight of LiBr, 0.05 to 1.0% by weight of LiOH, 10 to 400 ppm of Li 2 MoO 4 as MoO 4 2- , and 0.2 to 3% by weight of sec-octyl alcohol, the balance being water.
Claim 20
Dependent Claim 51 words
A hermetically closed circulation type, vapor absorption refrigerator according to claim 11, wherein the absorbing solution is an aqueous absorbing solution containing 50 to 70% by weight of LiBr, 0.05-0.5% by weight of LiOH and 50 to 350 ppm of LiNO 3 as NO 3 - , the balance being water.

References Cited (Backward Citations)

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US4487036A Cited
JPS6029872A Cited
JPS6211550A Cited
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JPH04226917A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-04-02 1993-10-02 1994-04-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-04-02 1997-10-02 1998-04-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-04-02 2001-10-02 2002-04-03 $7700.00 Window Closed / Lapsed

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