US3916989A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat exchanger
Assignee: Hitachi Ltd
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Filing: 1974-08-26
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Granted: 1975-11-04
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Expires: 1994-08-26
Abstract
Abstract A crossed fin-and-tube type heat exchanger comprising a plurality of fins arranged in juxtaposition to each other, each said fin having a suitable surface area, and a plurality of heat conductive tubes passed through and securely fixed to said fins such that the heat exchanging medium in said heat conductive tubes and another heat exchanging medium (air) passing between said fins will perform heat exchange through said heat conductive tubes and said fins. Each of said fins is provided with a plurality of rectangular slits formed by raising up the cut edges such that they are all transverse to the air stream flowing between the fins sinously along the outer peripheries of said heat conductive tubes, the raised-up portion of each said slit forming a ridge having a wall continuous to the upright at both ends of the slit and parallel to the fins.
Inventors
- 👤 Fumio Harada
- 👤 Takehiko Yanagida
- 👤 Kunio Fujie
- 👤 Hajime Futawatari
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:11
CPC Classifications
F; F28; F28F; F28F1/00; F28F1/10; F28F1/12; F28F1/24; F28F1/32; F28F1/325; Y; Y10; Y10S; Y10S165/00; Y10S165/454; Y10S165/50; Y10S165/501; Y10S165/502
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
160 words
In a crossed fin-and-tube type heat exchanger including a plurality of juxtaposed fins each having a suitable surface area and a plurality of heat conductive tubes passed through and securely fixed to said juxtaposed fins such that a first heat exhanging medium in said tubes and a second heat exchanging medium passing between the fins will perform heat exchange through said heat conductive tubes and said fins, the improvement comprising a plurality of louvers defining slits formed in said fins to extend substantially raadially around said heat conductive tubes and transversely to said second heat exchange medium passing between the fins, each of said plurality of louvers being formed from slotted and raised-up portions of said fins, each of said raised-up portions having upright walls longitudinally opposed to each other and a ridge wall continuous to said upright walls therebetween, said ridge wall being formed substantially parallel to said juxtaposed fins and positioned in a space between said juxtaposed fins.
Claim 2
Dependent Claim
160 words
In a crossed fin-and-tube type heat exchanger including a plurality of juxtaposed fins each having a suitable surface area and a plurality of heat conductive tubes passed through and securely fixed to said juxtaposed fins such that a first heat exhanging medium in said tubes and a second heat exchanging medium passing between the fins will perform heat exchange through said heat conductive tubes and said fins, the improvement comprising a plurality of louvers defining slits formed in said fins to extend substantially raadially around said heat conductive tubes and transversely to said second heat exchange medium passing between the fins, each of said plurality of louvers being formed from slotted and raised-up portions of said fins, each of said raised-up portions having upright walls longitudinally opposed to each other and a ridge wall continuous to said upright walls therebetween, said ridge wall being formed substantially parallel to said juxtaposed fins and positioned in a space between said juxtaposed fins.
Claim 3
Dependent Claim
39 words
A crossed fin-and-tube Type heat exchanger as set forth in claim 1, wherein said upright walls are formed substantially parallel to said second heat exchanging medium passing between said fins along the outer peripheries of said heat conductive tubes.
Claim 4
Dependent Claim
75 words
A crossed fin-and-tube type heat exchanger as set forth in claim 2, wherein said plurality of heat conductive tubes include at least one row of aligned heat conductive tubes, and wherein said plurality of louvers include first louvers extending between each adjoining heat conductive tubes in the direction of the tube row and second louvers extending obliquely on each side of the tube row so that said second louvers are equiangular with said first louvers.
Claim 5
Dependent Claim
101 words
A crossed fin-and-tube type heat exchanger as set forth in claim 2, wherein said plurality of heat conductive tubes include at least two rows of aligned heat conductive tubes, and wherein said plurality of louvers include first louvers extending between each adjoining heat conductive tubes in respective rows of said at least two rows in the direction of the tube rows and second louvers extending obliquely only on each outer side of said two tube rows so that said second louvers are equiangular with said first louvers and the section of the fin between said tube rows is free of louvers.
Claim 6
Dependent Claim
123 words
A crossed fin-and-tube type heat exchanger as set forth in claim 2, wherein said plurality of heat conductive tubes include at least three rows of aligned heat conductive tubes, and wherein said plurality of louvers include first louvers extending between each adjoining heat conductive tubes in opposed outer rows of said three rows of tubes in the direction of the tube row, second louvers extending obliquely on each outer side of the opposed outer tube rows so that said second louvers are equiangular with said first louvers extending between adjoining tubes in said outer rows, and third louvers extending between each adjoining heat conductive tubes in a middle tube row of said three rows of tubes in the direction of the tube row.
Claim 7
Dependent Claim
83 words
A crossed fin-and-tube type heat exchanger as set forth in claim 2, wherein said plurality of heat conductive tubes include at least three rows of aligned heat conductive tubes, and wherein said plurality of louvers include first louvers extending between each adjoining hat conductive tubes in the middle row of said three rows of tubes in the direction of the tube row and second louvers extending obliquely only on each outer side of opposed outer tube rows of said three rows of tubes.
Claim 8
Dependent Claim
79 words
A crossed fin-and-tube type heat exchanger as set forth in claim 2, wherein said plurality of heat conductive tubes include at least three rows of aligned heat conductive tubes, and wherein said plurality of louvers include first louvers extending between each of two adjoining tube rows of said three rows of tubes in the direction of the tube row and second louvers extending obliquely on each outer side of opposed outer tube rows of said three rows of tubes.
Claim 9
Dependent Claim
26 words
A crossed fin-and-tube type heat exchanger as set forth in claim 2, wherein said plurality of louvers include oblique slits, said oblique louvers being slightly curved.
Claim 10
Dependent Claim
54 words
A crossed fin-and-tube type heat exchanger asset forth in claim 1, wherein said plurality of louvers are rectangularly shaped with the long dimension of the rectangular shape extending the radial direction from each of said plurality of tubes, said long dimension being transverse to the direction of passing of said second heat exchanging medium.
References Cited (Backward Citations)
US3135320A
Cited
US3438433A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-03 | 1979-05-05 | 1979-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-03 | 1983-05-05 | 1983-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-03 | 1987-05-05 | 1987-11-04 | $7700.00 | Window Closed / Lapsed |