Flat tube heat exchanger and outdoor unit of air-conditioning apparatus including the heat exchanger

Patent metadata

Field	Value
Publication number	US-9657996-B2
Application number	US-201314442464-A
Country	US
Kind code	B2
Filing date	Jun 21, 2013
Priority date	Dec 10, 2012
Publication date	May 23, 2017
Grant date	May 23, 2017

Abstract

A flat tube heat exchange apparatus that has flat tubes arranged at a regular pitch in the step direction which is orthogonal to the row direction of fins. If the step direction pitch of the flat tubes is defined as Dp, the coefficient of Dp is k, and if 0<k<0.5 or 0.5<k<1, the distance between a fin end at one side in the step direction of the fins, and the center of a flat tube in the thickness direction is k·Dp, and the distance between a fin end at the other side in the step direction of the fins, and the center of a flat tube in the thickness direction is (1−k)·Dp.

First claim

The invention claimed is:

1. An outdoor unit of an air-conditioning apparatus, the outdoor unit comprising
flat tube heat exchangers including a plurality of single-row flat tube heat exchangers that are coupled to each other, each of the single-row flat tube heat exchangers including
flat tubes each having a rounded rectangular shape with a high aspect ratio in cross section, the flat tubes allowing a heat exchange medium to flow therein, and
a plurality of plate-shaped fins each provided, at one end thereof, with a plurality of insertion portions in which the flat tubes in a state of being bent into U shapes having hairpin corners are inserted, the fins being jointed to the flat tubes by brazing in a state where the flat tubes are inserted in the insertion portions, wherein

in the flat tube heat exchangers,
the flat tubes are arranged at a predetermined pitch in a stage direction orthogonal to a row direction of the fins,
a distance between fin ends at one side in the stage direction of the fins and a center in a thickness direction of the flat tubes is k·Dp and a distance between fin ends at the other end in the stage direction of the fins and the center in the thickness direction of the flat tubes is (1−k)·Dp, where Dp is a pitch of the flat tubes in the stage direction and k is a coefficient of Dp, and either 0<k<0.5 or 0.5<k<1,
an odd-numbered one of the single-row flat tube heat exchangers is disposed in opposite orientation with respect to the stage direction to an even-numbered one of the single-row flat tube heat exchangers with regard to an air flow direction,
upper and lower ends of the odd-numbered one of the single-row flat tube heat exchangers are aligned with upper and lower ends of the even-numbered one of the single-row flat tube heat exchangers,
the fins are arranged orthogonally to the flat tubes, and
the one end of each of the fins that is provided with the insertion portions, and one end of each of the flat tubes that is positioned at a shallow side with respect to each of the insertion portions, are aligned with each other.

2. The outdoor unit of claim 1 , wherein k satisfies one of 0.25 and 0.75.

3. The outdoor unit of claim 1 , wherein
the fins of the flat tube heat exchangers have surfaces on which a plurality of heat exchange accelerators are disposed, and
the odd-numbered one of the single-row flat tube heat exchangers and the even-numbered one of the single-row flat tube heat exchangers are disposed such that
the heat exchange accelerators are disposed at a side of the odd-numbered one of the single-row flat tube heat exchangers opposite to a side of the even-numbered one of the single-row flat tube heat exchangers at which the heat exchange accelerators are disposed.

4. The outdoor unit of claim 3 , wherein
the heat exchange accelerators of the flat tube heat exchangers are lanced parts of surfaces of the fins or waffle-like portions that form uneven areas on the surfaces of the fins.

5. The outdoor unit of claim 1 , wherein
the flat tubes are inserted into the insertion portions that are cut out from a side of the fins, and
two of the single-row flat tube heat exchangers are coupled to each other such that sides of the two of the single-row flat tube heat exchangers at which the insertion portions of the fins are not open face each other.

6. Flat tube heat exchangers as a plurality of single-row flat tube heat exchangers that are coupled to each other, each of the single-row flat tube heat exchangers comprising:
flat tubes each having a rounded rectangular shape with a high aspect ratio in cross section, the flat tubes allowing a heat exchange medium to flow therein; and
a plurality of plate-shaped fins each provided, at one end thereof, with a plurality of insertion portions in which the flat tubes in a state of being bent into U shapes having hairpin corners are inserted, the fins being jointed to the flat tubes by brazing in a state where the flat tubes are inserted in the insertion portions, wherein
the flat tubes are arranged at a predetermined pitch in a stage direction orthogonal to a row direction of the fins,
a distance between fin ends at one side in the stage direction of the fins and a center in a thickness direction of the flat tubes is k·Dp and a distance between fin ends at the other end in the stage direction of the fins and the center in the thickness direction of the flat tubes is (1−k)·Dp, where Dp is a pitch of the flat tubes in the stage direction and k is a coefficient of Dp, and either 0<k<0.5 or 0.5<k<1,
an odd-numbered one of the single-row flat tube heat exchangers is disposed in opposite orientation with respect to the stage direction to an even-numbered one of the single-row flat tube heat exchangers with regard to an air flow direction,
upper and lower ends of the odd-numbered one of the single-row flat tube heat exchangers are aligned with upper and lower ends of the even-numbered one of the single-row flat tube heat exchangers,
the fins are arranged orthogonally to the flat tubes, and
the one end of each of the fins that is provided with the insertion portions, and one end of each of the flat tubes that is positioned at a shallow side with respect to each of the insertion portions, are aligned with each other.

7. The flat tube heat exchangers of claim 6 , wherein satisfies one of 0.25 and 0.75.

Assignees

• Mitsubishi Electric Corp

Inventors

• Okazawa Hiroki
• Morikawa Yudai
• Ikuta Hiroya
• Nakajima Takashi
• Toyoshima Hiroki
• Kato Takashi

Classifications

• F28D1/0478

  the conduits having a non-circular cross-section · CPC title

• F24F1/14

  Heat exchangers specially adapted for separate outdoor units · CPC title

• F28F2215/12

  with U-shaped slots for laterally inserting conduits · CPC title

• F28D1/0435

  Combination of units extending one behind the other (F28D1/0452 takes precedence) · CPC title

• F28D7/0066 Primary

  Multi-circuit heat-exchangers, e.g. integrating different heat exchange sections in the same unit or heat-exchangers for more than two fluids (F28D7/103 takes precedence) · CPC title