Heat exchanger and method for manufacturing plate-shaped fins for heat exchanger

Patent metadata

Field	Value
Publication number	US-10041739-B2
Application number	US-201415504467-A
Country	US
Kind code	B2
Filing date	Sep 8, 2014
Priority date	Sep 8, 2014
Publication date	Aug 7, 2018
Grant date	Aug 7, 2018

Abstract

Plate-shaped fins of a heat exchanger each include, at circumferential portions thereof defining a notch in which a heat transfer tube having a flattened shape is disposed, fin collars formed by being raised from the circumferential portions. Each of the fin collars includes, in a position that faces a long axis side surface of the heat transfer tube, at least one reflare section bent in a direction opposite to the side surface. At least one of the reflare sections defining fin pitches between the adjoining plate-shaped fins is formed so that a reflare tip portion, which is a tip portion of the reflare section, is drawn apart from a contact side surface of the plate-shaped fin with which the reflare section comes into contact.

First claim

The invention claimed is:

1. A heat exchanger comprising:
a plurality of plate-shaped fins stacked at predetermined fin pitches, each of the plate-shaped fins being provided with a plurality of notches arranged in a longitudinal direction of the plate-shaped fins; and
a plurality of heat transfer tubes having a flattened shape, each of the heat transfer tubes being extended in a stacking direction of the plate-shaped fins and disposed in a corresponding one of the notches,
each of the plurality of plate-shaped fins including, at circumferential portions thereof defining the notches, fin collars being in contact with an outer circumference of the heat transfer tube,
each of the fin collars including at least one reflare section bent in a direction opposite to a side surface of the heat transfer tube being in contact with the fin collar,
the plate-shaped fins being arranged at the predetermined fin pitches so that the reflare section of one of the adjoining plate-shaped fins comes into contact with another one of the adjoining plate-shaped fins,
the at least one reflare section having a tip portion drawn apart from the adjoining plate-shaped fin,
each of the heat transfer tubes having a plurality of flow passages formed inside thereof arranged in a long axis direction of the heat transfer tube,
in a state where the reflare section having the tip portion is observed in a long axis direction of corresponding one of the heat transfer tubes, an angle θ formed by the tip portion and a contact side surface of the plate-shaped fin being in contact with the reflare section having the tip portion satisfying 0 degrees <θ<90 degrees.

2. The heat exchanger of any one of claim 1 , wherein,
in each of the fin collars provided at the circumferential portions defining the same notch, a plurality of the reflare sections each having the tip portion are provided along the long axis direction of corresponding one of the heat transfer tubes.

3. A heat exchanger comprising:
a plurality of plate-shaped fins stacked at predetermined fin pitches, each of the plate-shaped fins being provided with a plurality of notches arranged in a longitudinal direction of the plate-shaped fins; and
a plurality of heat transfer tubes having a flattened shape, each of the heat transfer tubes being extended in a stacking direction of the plate-shaped fins and disposed in a corresponding one of the notches,
each of the plurality of plate-shaped fins including, at circumferential portions thereof defining the notches, fin collars being in contact with an outer circumference of the heat transfer tube,
each of the fin collars including at least one reflare section bent in a direction opposite to the side surface of the heat transfer tube being in contact with the fin collar,
the plate-shaped fins being arranged at the predetermined fin pitches so that the reflare section of one of the adjoining plate-shaped fins comes into contact with another one of the adjoining plate-shaped fins,
the at least one reflare section having a tip portion drawn apart from the adjoining plate-shaped fin,
each of the heat transfer tubes having a plurality of flow passages formed inside thereof arranged in a long axis direction of the heat transfer tube,
in each of the fin collars provided at the circumferential portions defining the same notch, a plurality of the reflare sections each having the tip portion are provided along the long axis direction of corresponding one of the heat transfer tubes,
a distance between a first end portion serving as a windward side end portion of the heat transfer tube and the tip portion that is closest to the first end portion being longer than a distance between a second end portion serving as a leeward side end portion of the heat transfer tube and the tip portion that is closest to the second end portion.

4. The heat exchanger of claim 1 , wherein each of the notches includes, at an opening side end portion thereof, a guiding portion that is larger in width than the notch.

5. The heat exchanger of claim 1 , wherein the plurality of plate-shaped fins are provided with at least either scratches or slits.

6. A method for manufacturing the plate-shaped fins for the heat exchanger of claim 1 , comprising:
forming a plurality of groups of prepared holes at intervals in a plate-shaped member, each of the groups of prepared holes including at least two first prepared holes;
forming a cut line in each of the groups of prepared holes to connect the first prepared holes;
subjecting the cult line to burring processing to form raised portions that are to become the fin collars and an opening that is to become the notches;
subjecting the raised portions to reflare processing to form the reflare sections; and
cutting the plate-shaped member along an array direction of the groups of prepared holes to form the fin collars and the notches.

7. The method of claim 6 for manufacturing the plate-shaped fins for the heat exchanger, wherein the cut line that is formed is formed to have at least one point of intersection with an imaginary line connecting centers of the first prepared holes located at both ends of the same group of prepared holes.

8. The method of claim 6 , for manufacturing the plate-shaped fins for the heat exchanger, further comprising, between forming the raised portion and forming the reflare section, performing ironing or drawing on the raised portions so that a maximum height FCmax of each of the raised portions satisfies 1.0<(FCmax/FP) <2.0, wherein FP is the fin pitch.

9. The method of claim 6 for manufacturing the plate-shaped fins for the heat exchanger in which each of the notches includes, at an opening side end portion thereof, a guiding portion that is larger in width than the notch, wherein in forming the plurality of groups of prepared holes, a second prepared hole that is larger in diameter than the first prepared holes and is to become the guiding portion is formed in a position between the first prepared holes located at both ends of the same group of prepared holes.

10. The method of claim 6 for manufacturing the plate-shaped fins for the heat exchanger, further comprising pressing the plate-shaped member to form at least either scratches or slits.

11. The heat exchanger of claim 3 , wherein in the fin collars provided at the circumferential portions defining the same notch, the reflare sections each having the tip portion are provided in positions that face both long axis side surfaces of the heat transfer tube that come into contact with the fin collars, and
the plurality of the tip portions are alternately provided on both long axis side surfaces of the heat transfer tube that come into contact with the fin collars.

12. A heat exchanger comprising:
a plurality of plate-shaped fins stacked at predetermined fin pitches, each of the plate-shaped fins being provided with a plurality of notches arranged in a longitudinal direction of the plate-shaped fins; and
a plurality of heat transfer tubes having a flattened shape, each of the heat transfer tubes being extended in a stacking direction of the plate-shaped fins and disposed in a corresponding one of the notches,
each of the plurality of plate-shaped fins including, at circumferential portions thereof defining the notches, fin collars being in contact with an outer circumference of the heat transfer tube,
each of the fin collars including at least one reflare section bent in a direction opposite to the side surface of the heat transfer tube being in contact with the fin collar,
the plate-shaped fins being arranged at the predetermined fin pitches so that the reflare section of one of the adjoining plate-shaped fins com

Assignees

• Mitsubishi Electric Corp

Inventors

• Nakamura Shin
• Ishibashi Akira
• Higashiiue Shinya
• Ito Daisuke
• Matsui Shigeyoshi
• Ugajin Yuki
• Okazaki Takashi
• Mochizuki Atsushi

Classifications

• F25B39/00

  Evaporators; Condensers · CPC title

• F28F1/32 Primary

  the means having portions engaging further tubular elements · CPC title

• B21D53/08

  of both metal tubes and sheet metal (connecting tubes in openings B21D39/06) · CPC title

• F28D2021/0071

  Evaporators · CPC title

• F28D1/0535

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