Flat-type refrigerant tube having an improved pressure-resistant strength

• US 5,476,141 A
• Filed: 04/19/1994
• Issued: 12/19/1995
• Est. Priority Date: 04/19/1993
• Status: Expired due to Term

• Current Assignee: Sanden Corporation (Hisense Home Appliances Group Co., Ltd.)
• Original Assignee: Sanden Corporation (Hisense Home Appliances Group Co., Ltd.)
• Inventors: Tanaka, Hiroshi
• Primary Examiner(s): Flanigan, Allen J.
• Application Number:
  US08/229,668
• Time in Patent Office: 609 Days
• Field of Search: 165/173, 165/179, 165/183
• US Class Current: 165/183
• CPC Class Codes: F28D 1/05391 with multiple rows of conduits or with multi-channel conduits combined with a particular flow pattern, e.g. multi-row multi-stage radiators
• CPC Class Codes: F28D 2021/0084 Condensers
• CPC Class Codes: F28F 1/022 with multiple channels
• CPC Class Codes: F28F 1/40 the means being only inside the tubular element
• CPC Class Codes: F28F 3/04 the means being integral with the element

Abstract

A flat-type refrigerant tube for use in an heat exchanger which has a plurality of refrigerant passage chambers formed in a flat aluminum plate having a first end and a second end, the chambers extending from the one end to the opposite end in parallel with first another and arranged in a plane parallel to the flat outer surface of the flat tube, each of the chambers having a rectangular cross-section with four corners which is determined by a first pair of opposite sides with a dimension of A and a second pair of opposite sides with a dimension of B perpendicular to the first pair of opposite sides. Each of the four corners is formed with a curvature R determined by the following formula: 0.2 mm≦R≦D/2, where D equals A when A≦B but equals B when B<A. Each of the chambers can be provided with at least one of elongated ribs longitudinally extending on the inner surface thereof.

Claims

1. A refrigerant tube of a flat type which comprises a flat aluminum plate having a length from a first end to a second end, said plate having a plurality of chambers extending therein from the first end to the second end and arranged in parallel with each other in a plane parallel to said plate, each of said plurality of chambers being defined to have a rectangular cross-section by a first pair of wall surfaces which are parallel with and separated by a first dimension D from each other and a second pair of wail surfaces which are parallel with and separated by a second dimension greater than or equal to said first dimension from each other and perpendicular to said first pair of wall surfaces, said first pair of wall surfaces connecting to said second pair of wall surfaces to form four comers of each of said chambers having said rectangular cross-section, each of said comers being formed with a curvature R determined by the following formula:

space="preserve" listing-type="equation">0.2 mm≦

R<

<

D/2.

2. A refrigerant tube as claimed in claim 1, wherein at least said first pair of wall surfaces in each of said plurality of chambers has at least one elongated protrusion extending from said first end to said second end in parallel with said plurality of chambers.

3. A refrigerant tube as claimed in claim 2, wherein a plurality of said elongated protrusions each having a pair of rising edges separated by a width W are formed on at least said first pair of wall surfaces with a distance S remaining between rising edges of two adjacent ones of said elongated protrusions, said width W and said distance S being determined by the following formula:

space="preserve" listing-type="equation">S≦

W.

4. A refrigerant tube as claimed in claim 2, wherein said at least one elongated protrusion has a width W and a height H determined by the following formula:

space="preserve" listing-type="equation">4.5×

W≦

H.

7. A refrigerant robe as claimed in claim 1, wherein at least said second pair of wall surfaces in each of said plurality of chambers has at least one elongated protrusion extending from said first end to said second end in parallel with said plurality of chambers.

8. A refrigerant robe as claimed in claim 7, wherein a plurality of said elongated protrusions each having a pair of rising edges separated by a width W are formed on at least said second pair of wall surfaces with a distance S remaining between rising edges of two adjacent ones of said elongated protrusions, said width W and said distance S being determined by the following formula:

space="preserve" listing-type="equation">S≦

W.

9. A refrigerant tube as claimed in claim 7, wherein said at least one elongated protrusion has a width W and a height H determined by the following formula:

space="preserve" listing-type="equation">4.5×

W≦

H.

10. The refrigerant tube as claimed in claim 1, wherein D/2 equals 0.3 mm.

5. A refrigerant tube of a first type which comprises a flat aluminum plat having a length from a first end to a second end, said plate having a plurality of chambers extending therein from the first end to the second end and arranged in parallel with each other in a plane parallel to said plate, said plurality of chambers comprising two outermost chambers and inner chamber disposed between said two outermost chambers, each of said two outermost chambers having a U-shaped cross section and being defined by a pair of wall surfaces which are parallel to said plane and separated from each other by a first dimension A left therebetween, a curved wall surface being an inner surface of each of outermost opposite side walls of said tube and connecting between said pair of walls, and a wall surface being opposite to said curved wall surface and perpendicular to the pair of wall surfaces, said pair of wall surfaces connecting to said perpendicular wall surface to form two comers of said each of outermost chambers having the U-shaped cross-section, each of said inner chambers having a rectangular cross-section and being defined by a first pair of wall surfaces which are parallel to said plane and separated from each other by the first dimension A and a second pair of wall surfaces which are perpendicular to said first pair of wall surfaces and separated from each other by a second dimension B, said first pair of wall surfaces connecting to said second pair of wall surfaces to form four comers of each of the inner chambers having the rectangular cross-section, each of the comers of said outermost chambers and said inner chambers having a curvature R determined by the following formula:

space="preserve" listing-type="equation">0.2 mm≦

R<

<

D/2,

where D equals A when A≦

B but equals B when B<

A.

11. The refrigerant tube as claimed in claim 5, wherein D/2 equals 0.3 mm.

6. A heat exchanger comprising a plurality of refrigerant tubes of a flat type each having an interior and a length and arranged at an interval between each adjacent pair of said refrigerant robes, a plurality of corrugated radiator fins attached to said refrigerant robes to be interposed between each adjacent pair of said plurality of refrigerant tubes, and a pair of header pipes opposite to each other and each having an interior and each located at opposite ends of said plurality of refrigerant robes, respectively, each of said opposite ends of said plurality of refrigerant robes being inserted into one of a plurality of apertures formed in peripheral surfaces of said pair of header pipes and bonded to said pair of header pipes, respectively, so that the interior of said plurality of refrigerant robes communicates with the interior of said pair of header pipes, each of said plurality of refrigerant robes comprising a flat aluminum plate of a length from a first end to a second end with a plurality of chambers extending therein from the first end to the second end and arranged in parallel with each other in a plane parallel to said plate, each of said plurality of chambers being defined to have a rectangular cross-section by a first pair of wall surfaces which are parallel with and separated by a first dimension D from each other and a second pair of wall surfaces which are parallel with and separated by a second dimension greater than or equal to said first dimension from each other and perpendicular to said first pair of wall surfaces, said first pair of wall surfaces connecting to said second pair of wall surfaces to form four comers of each of said chambers having said rectangular cross-section, each of said comers being formed with a curvature R determined by the following formula:

space="preserve" listing-type="equation">0.2 mm≦

R<

<

D/2.

12. The refrigerant tube as claimed in claim 6, wherein D/2 equals 0.3 mm.