US20110113824A1

US20110113824A1 - Evaporator

Info

Publication number: US20110113824A1
Application number: US13/003,284
Authority: US
Inventors: Husnu Kerpicci
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2008-07-07
Filing date: 2009-07-07
Publication date: 2011-05-19
Also published as: CN102089602A; WO2010003938A1; CN102089602B; EP2324305A1; EP2324305B1

Abstract

The present invention relates to an evaporator (1) comprising a sheet (2) and a microchannel tube (3) used in the cooling cycle, having channels (K) parallel to each other wherein the refrigerant flows.

Description

The present invention relates to an evaporator having a microchannel tube.
In cooling devices and air conditioners, the evaporator executes the cooling process by absorbing the ambient thermal energy. The wider the contact surface of the evaporator with the air is, the more efficient the heat exchange and hence the cooling process. One of the most preferred methods for widening the surface is bending the evaporator tubes in serpentine form and wrapping them on a conductor sheet. However, when microchannel tube providing more effective evaporation is desired to be used in evaporators instead of standard tube, a number of problems are encountered. For example, deformations may occur on the surface of the microchannel tube when it is desired to be wrapped on a sheet, which may prevent the refrigerant passing therein from flowing. Particularly in the evaporators used in cooling devices, when the microchannel tube used in the freezing chamber is desired to be used in the cooling chamber, the microchannel tube cannot be bent easily, therefore a thinner tube is required to be used in the cooling chamber.
In the state of the art the United States of America Patent Applications No U.S. Pat. No. 5,765,393 and US2006130517, the evaporator comprises microchannels and parallel tubes providing the refrigerant cycle to continue by the ends of the microchannels being disposed therein.
In the state of the art Japanese Patent Application No JP2002107069, the contact surface with the air is increased by bending the microchannel evaporator tube in spiral form. However, in this embodiment the microchannel tube occupies more space than desired in cooling devices due to the wide bending angle required for the microchannel tube to be bent without being deformed.
The aim of the present invention is the realization of an evaporator wherein the microchannel tube is used efficiently.
The evaporator realized in order to attain the aim of the present invention is explicated in the claims.
The evaporator comprises a microchannel tube and a sheet.
The evaporator furthermore comprises a microchannel tube that consists of channels arranged side by side on an axis vertical to the sheet so as one of them to be fixed to the sheet, and fixed on the sheet by bending around the axis whereon the channels are arranged in line.
In an embodiment of the present invention, the microchannel tube has a rectangular or elliptical cross section. The microchannel tube is fixed to the sheet from the narrow edge, while the side by side arranged channels are located on the wide edge. The microchannel tube is bent on the sheet surface with more than one bending wherein one surface of the narrow edge is deformed by becoming narrower without any change in the width of the wide edge. By means of the microchannel tube not being bent on the wide surface, the channels are prevented from being deformed in different rates and more than the other.
In an embodiment of the present invention, the microchannel tube is disposed on the sheet by bending in serpentine form.
In another embodiment of the present invention, the microchannel tube is fixed to the sheet by bending in spiral form.
The microchannel tube is enabled to be used longer in a narrow space in the cooling device by being bent in various forms. Bending of the microchannel tube around the axis whereon the channels are arranged vertically provides the microchannel tube to be bent easily without being damaged.
In an embodiment of the present invention, the evaporator comprises at least one support member fixed vertically on the sheet whereon the microchannel tube bears. The support member helps the microchannel tube to be fixed on the sheet by bearing on the microchannel tube.
In an embodiment of the present invention, the support member enables the microchannel tube to retain the shape given by being disposed on a similar line with the microchannel tube on the sheet.
In another embodiment of the present invention, the support member is shaped as a pin. The pins are fixed on the sheet along the direction, which the microchannel tube is desired to be disposed, at various distances.
In another embodiment of the present invention, the support member bears on the inner side of the bend portion of the serpentine shaped microchannel tube. Thus, the deformed bending points are strengthened.
In yet another embodiment of the present invention, the support member has a plate shape. The plate shaped support member contacting the microchannel tube increases the heat exchange with the sheet.
By means of the evaporator of the present invention, the microchannel tube is enabled to be fixed on the sheet by bending without being damaged. Thus, the efficiency of the evaporation process is increased by increasing the contact surface of the refrigerant with the air.

The evaporator realized in order to attain the aim of the present invention is illustrated in the attached figures, where:

FIG. 1—is the perspective view of an evaporator.

FIG. 2—is the perspective view of detail X in FIG. 1.

FIG. 3—is the perspective view of an evaporator comprising pin shaped support members in an embodiment of the present invention.

FIG. 4—is the schematic view of an evaporator comprising a microchannel tube bending in different diameters between the support members in another embodiment of the present invention.

FIG. 5—is the perspective view of the usage of an evaporator in a cooling device with two chambers in another embodiment of the present invention.

FIG. 6—is the schematic view of an evaporator comprising a spiral shaped microchannel tube used in a cooling device with two chambers in another embodiment of the present invention.

FIG. 7—is the perspective view of an evaporator comprising a spiral shaped microchannel tube and a support member in another embodiment of the present invention.

The elements illustrated in the figures are numbered as follows:
1. Evaporator
2. Sheet
3. Microchannel tube
4. Support member
The symbols below are used to explain the evaporator (1) of the present invention.
K: Channel located in the microchannel tube (3)
A: Straight portion of the microchannel tube (3) bent in serpentine form
B: Bend portion of the microchannel tube (3) bent in serpentine form
E: Axis vertical to the sheet (2)
R₁: Radius of the bend portion
R₂: Radius of the curve formed while the microchannel tube (3) passes under one and over the other one of the two support members (4) located on the same plane
The evaporator (1) of the present invention comprises a sheet (2) and a microchannel tube (3) used in the cooling cycle, having arranged channels (K) parallel to each other wherein the refrigerant flows.
The evaporator (1) furthermore comprises a microchannel tube (3)

- fixed on the sheet (2)
- by bending around the axis (E) that is vertical to the sheet (2) and on which the channels (K) are in line,
- such that only one of its channels (K) will be in contact (FIGS. 1 and 2).

The channels (K) are provided to be deformed evenly by means of the bending of the microchannel tube (3) around the axis (E) whereon the channels (K) are arranged in order. Thus, the refrigerant flows in the channels (K) having equal cross sections. Furthermore, the side by side arranged channels (K) are bent easily around the axis (E) whereon the channels (K) are arranged.
In an embodiment of the present invention, the microchannel tube (3) has a rectangular cross section. The channels (K) are arranged side by side on the wide edge of the rectangular and the microchannel tube (3) is fixed to the sheet (2) from the narrow edge (FIGS. 1-2). The channels (K) arranged on a single line on the bending axis (E) are evenly and a little deformed while the microchannel tube (3) is bent around the narrow edge and the flow of the refrigerant passing therein is not prevented.
In an embodiment of the present invention, the evaporator (1) comprises a microchannel tube (3) tubed on the sheet (2) by being bent in serpentine form. In this embodiment, the microchannel tube (3) comprises more than one straight portion (A) shaped as lines parallel to each other and more than one bend portion (B) joining the straight portions (A) with leaps from right and from left respectively. The channels (K) arranged side by side in the microchannel tube (3) form the bend portions (B) by being deformed evenly on the axis (E) vertical to the sheet (2) (FIGS. 1 and 3).
In another embodiment of the present invention, the evaporator (1) comprises a microchannel tube (3) fixed on the sheet (2) by being tubed in spiral form on the sheet (2) surface. The spiral may be shaped as the Archimedes spiral (FIGS. 6-7) or the Fermat spiral.
In an embodiment of the present invention, the evaporator (1) comprises at least one support member (4) fixed on the sheet (2) whereon the microchannel tube (3) bears in the direction of the axis (E) whereon the channels (K) are arranged in line. The support member (4) is of a heat conducting material as the sheet (2) and welded or fastened with rivets almost to the entire surface of the sheet (2) with certain distances. The support member (4) helps the microchannel tube (3) to be fixed on the sheet (2) in the desired form (FIGS. 1-7).
In an embodiment of the present invention, the support member (4) extends along the microchannel tube (3) in accordance with the shape of the microchannel tube (3) formed by being bent.
In another embodiment of the present invention, the support member (4) is shaped as a pin.
In another embodiment of the present invention, the support member (4) bears on the inner side of the bend portion (B) of the serpentine shaped microchannel tube (3).
In another embodiment of the present invention, the support member (4) has a plate shape having almost the same width as the microchannel tube (3).
In yet another embodiment of the present invention, the evaporator (1) comprises a microchannel tube (3), wherein the diameter (R1) forming the passage from the straight portion (A) to the bend portion (B) of the serpentine is wider than the diameter (R2) forming the passage from the bend portion (B) to the straight portion (A) below, and which is fixed on a stretch-formed sheet (2) by passing under the support member (4) of the bend portion (B) that is almost at the same level as the straight support member (4) below and then by forming the straight portion (A) of the serpentine on the straight support member (4) below (FIG. 4). Thus no other fixing method is required.
In an embodiment of the present invention, the evaporator (1) is used in a cooling device with two chambers, one being cooler and the other freezer. The microchannel tube (3) is carried to the cooling chamber without any change in the form after being wrapped to the freezing chamber and is tubed on the sheet (2). Thus, the evaporation process of both the freezing and the cooling chambers can be realized by only one microchannel tube (3) without the need of any other add-on element. In an embodiment of the present invention, the wrapping device that wraps the microchannel tube (3) to the evaporator (1) bending in the freezing chamber by turning can also wrap the microchannel tube (3) on the sheet (2) located in the cooling chamber in spiral form in a similar way (FIGS. 5 and 6).
By means of the evaporator (1) of the present invention, the contact surface of the refrigerant with the air is increased by the microchannel tube (3), sheet (2) and support members (4). The refrigerant is enabled to move similarly from each channel (K) without being much deformed by means of the channels (K) arranged side by side in the microchannel tube (3) bending on the axis (E) vertical to the sheet (2). The support members (4) located on the sheet (2) strengthen the bending points of the microchannel tube (3) and help the given shape to remain as desired.

Claims

1. An evaporator (1) comprising a sheet (2) and a microchannel tube (3) used in the cooling cycle, having arranged channels (K) parallel to each other wherein

the refrigerant flows, characterized by a microchannel tube (3)

fixed on the sheet (2)

by bending around the axis (E) that is vertical to the sheet (2) and on which the channels (K) are in line,

such that only one of its channels (K) will be in contact.

2. An evaporator (1) as in claim 1, characterized in that the microchannel tube (3) has a rectangular cross section, wherein the channels (K) are arranged side by side on the wide edge and which is fixed to the sheet (2) from over the narrow edge.

3. An evaporator (1) as in claims 1 and 2, characterized in that the microchannel tube (3) being fastened on the sheet by bending in serpentine form.

4. An evaporator (1) as in claims 1 and 2, characterized in that the microchannel tube (3) being fastened on the sheet by bending in spiral form.

5. An evaporator (1) as in any one of the above claims, characterized by one or more than one support member (4) fixed on the sheet (2) whereon the microchannel tube (3) bears in the direction of the axis (E) whereon the channels (K) are arranged in line.

6. An evaporator (1) as in claim 5, characterized in that the support member (4) extends along the microchannel tube (3) in accordance with the shape of the microchannel tube (3).

7. An evaporator (1) as in claim 5, characterized in that the support member (4) has a plate shape that has almost the same width as the microchannel tube (3).

8. An evaporator (1) as in claim 5, characterized in that the support member (4) is shaped as a pin.

9. An evaporator (1) as in claim 5, 6, 7 or 8, characterized in that the support member (4) bears on the inner side of the bend portion (B) of the microchannel tube (3) bent in serpentine form.

10. An evaporator (1) as in claims 5 to 9, characterized in that the microchannel tube (3) being fixed on the sheet (2) by being passed under one and over the other one of the support members (4) and thus by being compressed between the support members (4).

11. An evaporator (1) as in any one of the above claims, characterized by being used in a cooling device wherein the evaporation processes both in the freezing and the cooling chambers are realized by only one microchannel tube (3).