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US5720340A Expired / Lapsed US ⏱️ 0.0 years remaining

Laminated type heat exchanger

Assignee: Denso Corp
•
Filing: 1996-07-16
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Granted: 1998-02-24
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Expires: 2016-07-16
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Abstract

Abstract A laminated type heat exchanger includes a plurality of refrigerant passages which are formed by pairs of core plates. Each core plate comprises an outer covering layer, a core layer, and an inner covering layer. The outer covering layer is made of a brazing material of which electric potential is more negative than the core layer while the inner covering layer is made of a brazing material of which electric potential is equal to or more positive than the core layer. The refrigerant passages are formed by brazing only the adjacent two of the inner covering layer. The outer covering layer works as a sacrificial corrosive material with respect to the inner covering layer and the core layer. Leakage of refrigerant from the brazed portions of the core plates is prevented, whereby the corrosion resistance of the laminated type heat exchanger is improved.

Inventors

  • 👤 Toshio Ohara
  • 👤 Yasukazu Aikawa
  • 👤 Yoshiharu Kajikawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 18:12
CPC Classifications
F; F28; F28F; F28F21/00; F28F21/08; F28F21/081; F28F21/084; F28D; F28D1/00; F28D1/02; F28D1/03; F28D1/0308; F28D1/0325; F28D1/0333; F28D1/0341; F28F19/00; F28F19/004; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/4935; Y10T29/49393

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 218 words
A laminated type heat exchanger comprising: a pair of core plates joined to form a fluid passage therebetween and laminated in plural numbers to form a passage unit; a tank portion having a tube-like shape and integrally formed with each of said core plates at a longitudinal end of said core plates to form a tank in fluid communication with said passage unit; and corrugated fins disposed between adjacent pairs of core plates, wherein each of said core plates comprises laminated layers of a core layer, an outer covering layer disposed on an outer side of said tank portion and said fluid passage and made of a material of which electrical potential is more negative than said core layer, and an inner covering layer disposed on an inner side of said tank portion and said fluid passage and made of a material of which electrical potential is more positive than said core layer; said pair of core plates being joined only with said inner covering layers thereof; and said tank portion having a flange portion at an end thereof, which is bent to protrude outward from an outer surface of said tank portion and to expose said inner covering layer to be joined with said inner covering layer of another tank portion of adjacent pair of core plates.
Claim 2
Dependent Claim 218 words
A laminated type heat exchanger comprising: a pair of core plates joined to form a fluid passage therebetween and laminated in plural numbers to form a passage unit; a tank portion having a tube-like shape and integrally formed with each of said core plates at a longitudinal end of said core plates to form a tank in fluid communication with said passage unit; and corrugated fins disposed between adjacent pairs of core plates, wherein each of said core plates comprises laminated layers of a core layer, an outer covering layer disposed on an outer side of said tank portion and said fluid passage and made of a material of which electrical potential is more negative than said core layer, and an inner covering layer disposed on an inner side of said tank portion and said fluid passage and made of a material of which electrical potential is more positive than said core layer; said pair of core plates being joined only with said inner covering layers thereof; and said tank portion having a flange portion at an end thereof, which is bent to protrude outward from an outer surface of said tank portion and to expose said inner covering layer to be joined with said inner covering layer of another tank portion of adjacent pair of core plates.
Claim 3
Dependent Claim 43 words
A laminated type heat exchanger according to claim 1, wherein a middle layer of which electrical potential is more negative than said core layer and more positive than said outer covering layer is formed between said core layer and said outer covering layer.
Claim 4
Dependent Claim 24 words
A laminated type heat exchanger according to claim 1, wherein said outer covering layer and said inner covering layer are made of brazing materials.
Claim 5
Dependent Claim 18 words
A laminated type heat exchanger according to claim 1, wherein said core plates are made of aluminum alloys.
Claim 6
Dependent Claim 25 words
A laminated type heat exchanger according to claim 1, wherein said laminated type heat exchanger is used for an evaporator of an air conditioning system.
Claim 7
Dependent Claim 44 words
A laminated type heat exchanger according to claim 1, wherein said outer covering layer is made of A4104 and 2-5 wt % Zn, said core layer is made of A3003, and said inner covering layer is made of A4104 and 0.5 wt % Cu.
Claim 8
Dependent Claim 17 words
A laminated type heat exchanger according to claim 1, wherein said core layer is added with titanium.
Claim 9
Dependent Claim 220 words
A laminated type heat exchanger comprising: a pair of core plates joined to form a fluid passage therebetween and laminated in plural numbers to form a passage unit; a tank portion having a tube-like shape, integrally formed with each of said core plates at a longitudinal end of said core plates to protrude approximately in a perpendicular direction relative to said core plates and to have a flange portion at an end opposite to a core plate side end thereof, said tank portion forming a tank in fluid communication with said passage unit; and corrugated fins disposed between adjacent pairs of core plates to face said flange portion of said tank portion, wherein each of said core plates comprises laminated layers of a core layer, an outer covering layer disposed on an outer side of said tank portion and said fluid passage, and an inner covering layer disposed on an inner side of said tank portion and said fluid passage and made of a material of which electrical potential is more positive than said core layer; and said flange portion of said tank portion protrudes outward from an outer surface of said tank portion and exposes said inner covering layer thereon to be joined only with said inner covering layer of another tank portion of adjacent pair of core plates.
Claim 10
Dependent Claim 220 words
A laminated type heat exchanger comprising: a pair of core plates joined to form a fluid passage therebetween and laminated in plural numbers to form a passage unit; a tank portion having a tube-like shape, integrally formed with each of said core plates at a longitudinal end of said core plates to protrude approximately in a perpendicular direction relative to said core plates and to have a flange portion at an end opposite to a core plate side end thereof, said tank portion forming a tank in fluid communication with said passage unit; and corrugated fins disposed between adjacent pairs of core plates to face said flange portion of said tank portion, wherein each of said core plates comprises laminated layers of a core layer, an outer covering layer disposed on an outer side of said tank portion and said fluid passage, and an inner covering layer disposed on an inner side of said tank portion and said fluid passage and made of a material of which electrical potential is more positive than said core layer; and said flange portion of said tank portion protrudes outward from an outer surface of said tank portion and exposes said inner covering layer thereon to be joined only with said inner covering layer of another tank portion of adjacent pair of core plates.
Claim 11
Dependent Claim 27 words
A laminated type heat exchanger according to claim 8, wherein electric potential of said inner covering layer is almost equal to electric potential of said core layer.
Claim 12
Dependent Claim 28 words
A laminated type heat exchanger according to claim 1, wherein a difference in electrical potentials between said inner covering layer and said core layer is about 0-20 mV.
Claim 13
Dependent Claim 24 words
A laminated type heat exchanger according to claim 1, wherein said corrugated fins are fixed to said outer covering layer of said core plates.
Claim 14
Dependent Claim 187 words
A core plate for a laminated type heat exchanger in which fluid flows for exchanging heat with an outside atmosphere, said core plate comprising: a core member having a passage portion for forming a fluid passage with another core plate, and a tank portion formed at a longitudinal end of said passage portion to protrude approximately perpendicularly with respect to the passage portion, said tank portion having a tube-like shape with flange portions at both ends thereof; an outer covering layer having more negative electrical potential than said core member, said outer covering layer formed on a first surface of said core member to be entirely exposed to said outside atmosphere; and an inner covering layer having more positive electrical potential than said core member, said inner covering layer formed on a second surface of said core member to be isolated from said outside atmosphere, said second surface of said core member including end surfaces of said flange portions of said tank portion, said end surfaces of said flange portions which are to be joined to other core plates, respectively, to form said laminated type heat exchanger.
Claim 15
Dependent Claim 187 words
A core plate for a laminated type heat exchanger in which fluid flows for exchanging heat with an outside atmosphere, said core plate comprising: a core member having a passage portion for forming a fluid passage with another core plate, and a tank portion formed at a longitudinal end of said passage portion to protrude approximately perpendicularly with respect to the passage portion, said tank portion having a tube-like shape with flange portions at both ends thereof; an outer covering layer having more negative electrical potential than said core member, said outer covering layer formed on a first surface of said core member to be entirely exposed to said outside atmosphere; and an inner covering layer having more positive electrical potential than said core member, said inner covering layer formed on a second surface of said core member to be isolated from said outside atmosphere, said second surface of said core member including end surfaces of said flange portions of said tank portion, said end surfaces of said flange portions which are to be joined to other core plates, respectively, to form said laminated type heat exchanger.
Claim 16
Dependent Claim 41 words
A core plate according to claim 12, further comprising a middle layer formed between said core member and said outer covering layer, electrical potential of which is more negative than said core member and more positive than said outer covering layer.
Claim 17
Dependent Claim 22 words
A core plate according to claim 12, wherein said outer covering layer and said inner covering layer are made of brazing materials.
Claim 18
Dependent Claim 16 words
A core plate according to claim 12, wherein said core plates are made of aluminum alloys.
Claim 19
Dependent Claim 23 words
A core plate according to claim 12, wherein said laminated type heat exchanger is used for an evaporator of an air conditioning system.
Claim 20
Dependent Claim 41 words
A core plate according to claim 12, wherein said outer covering layer is made of A4104 and 2-5 wt % Zn, said core member is made of A3003, and said inner layer is made of A4104 and 0.5 wt % Cu.
Claim 21
Dependent Claim 15 words
A core plate according to claim 12, wherein titanium is added to said core member.

References Cited (Backward Citations)

JPS6383596A Cited
JPS63273792A Cited
JPS6442394A Cited
JPH0285697A Cited
US4949543A Cited
US5042574A Cited
US5125452A Cited
JPH04131698A Cited
US5176205A Cited
JPH0611295A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2001-02-23 2001-08-25 2002-02-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2005-02-23 2005-08-25 2006-02-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2009-02-23 2009-08-25 2010-02-24 $7700.00 Window Closed / Lapsed

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