JP2008261542A - Evaporator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an evaporator free from degradation of cooling performance even when frost is attached, by suppressing attachment of frost to a plate fin. <P>SOLUTION: This evaporator 1 has a plurality of plate fins 4 laid at prescribed intervals, and a refrigerant pipe 5 penetrating through the plate fins 4 and arranged in a meandering state. A refrigerant inlet part 51 of the refrigerant pipe 5 is provided with an exposed pipe part 52 laid at an upper part of top end faces of the plate fins 4 along the arrangement direction A without penetrating through the plate fins 4. As the exposed pipe part 52 is kept in a state of lowest temperature by allowing the refrigerant to flow therein, a temperature of the exposed pipe part 52 is lower than the plate fins 4. As the frost has a property that it attaches to a part of lower temperature, the frost generated in the evaporator 1, attaches to the exposed pipe part 52. As a result, the attachment of frost to the plate fins 4 can be suppressed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an evaporator in which the cooling performance does not deteriorate even if frost adheres by suppressing adhesion of frost to the plate fins.

  The evaporator mounted on the air cooler includes a plurality of plate fins arranged at predetermined intervals, and a refrigerant pipe that passes through these plate fins and is drawn in a meandering state. The air to be cooled is cooled by heat exchange with the refrigerant when passing between the plate fins.

  If the air to be cooled contains moisture, part of the moisture is solidified by the evaporator and becomes frost and adheres to the plate fins. When the air in the sealed space is cooled, frost adheres to the plate fins in a certain amount. However, when the inside of the temperature chamber of the environmental test device is cooled by an air cooler, the outside air containing moisture flows in and out of the work, so frost accumulates as the operation time elapses, and the plate Clogging may occur between the fins.

  When clogging occurs between the plate fins, sufficient heat exchange between the refrigerant and the air is not performed, so that the cooling performance is deteriorated. In addition, since the air flow path is closed, an abnormality such as a decrease in atmospheric pressure may occur inside the air cooler and the apparatus may be stopped.

Here, a technique capable of avoiding a decrease in cooling performance or closing of an air flow path even when frost adheres by changing the shape and arrangement interval of plate fins is described in Patent Document 1. Yes.
JP 7-12490 A

  However, in the above technique, air flows due to frost accumulated between a cylindrical container forming an air flow path and fins attached to a refrigerant pipe of an evaporator disposed in the cylindrical container. In order to prevent the passage from being closed and to prevent the frost accumulated between the plate fins from being closed, it is possible to avoid closing the air flow path and lowering the cooling performance due to clogging. Absent.

  In view of these points, an object of the present invention is to provide an evaporator and an evaporator with frost that prevent cooling performance from being deteriorated even if frost adheres by suppressing adhesion of frost between plate fins. It is to propose a prevention method.

  In order to solve the above problems, an evaporator according to the present invention includes a plurality of plate fins arranged at a predetermined interval, a refrigerant pipe routed through the plate fins, An exposed tube portion formed in the refrigerant inlet portion of the refrigerant tube and routed along the arrangement direction of the plate fins without penetrating the plate fins, and between the plate fins and the exposed tube portion. A heat exchange path through which air to be cooled flows, and the exposed pipe portion is disposed outside the plate fin.

  According to the present invention, the refrigerant pipe includes the exposed pipe portion at the refrigerant inlet portion where the temperature is lowest when the refrigerant flows in. Therefore, the temperature of the exposed tube portion is lower than that of the plate fin. Since frost has a property of adhering to a lower temperature portion, frost generated when the air to be cooled passes through the heat exchange path adheres to the exposed pipe portion. As a result, frost can be prevented from adhering to the plate fins, so that clogging occurs between the plate fins even when the evaporator is operated for a long time in an environment where moisture outside air flows in. Can be avoided. Therefore, the cooling capacity of the evaporator does not decrease due to frost adhesion. Further, the heat exchange path is not closed due to adhesion of frost.

  In the present invention, the plate fin has a rectangular outline, and the refrigerant pipe is in a meandering state from the first end face side of the plate fin toward the second end face facing the first end face. It is preferable that the exposed pipe portion is arranged outside the first end face along the first end face of each plate fin. The temperature on the first end face side of the plate fin on which the upstream side of the refrigerant flow path in the refrigerant pipe is routed is compared with the temperature on the second end face side on which the downstream side of the refrigerant flow path in the refrigerant pipe is routed. It is low. Therefore, if the exposed tube portion is provided outside the first end surface, frost is likely to adhere to the exposed tube portion. Moreover, even if frost adheres to the exposed tube portion, the flow of air passing through the heat exchange path between the plate fins is not hindered.

  Further, the plate fin has a rectangular outline, and the refrigerant pipe is drawn in a meandering state from the first end face side of the plate fin toward the second end face facing the first end face. The exposed tube portion may be disposed outside the end surface along one end surface orthogonal to the first end surface and the second end surface of the plate fin.

  The plate fins arranged at a predetermined interval include a first plate fin group arranged at a predetermined interval, and a second plate fin group arranged at a predetermined interval, and the first The plate fin group and the second plate fin group are separated from each other by a predetermined distance in a direction orthogonal to the plate fin arrangement direction, and the exposed tube portion is located between the first plate fin group and the second plate fin group. It can also be arranged.

  In the present invention, in order to increase the surface area of the exposed tube portion and attach more frost to the exposed tube portion, the exposed tube portion has auxiliary plate fins arranged at a wider interval than the interval between the plate fins. It is preferable that the portion is routed so as to penetrate these auxiliary plate fins. Since the area where frost can be attached is large, even when the evaporator is operated for a long time, the plate fins are not clogged.

  Next, the present invention relates to a method for preventing frost formation of an evaporator, wherein the refrigerant inlet portion of a refrigerant pipe routed in a state of penetrating a plurality of plate fins arranged at a predetermined interval is used for these. An exposed pipe portion having a predetermined length drawn in the arrangement direction of the plate fin without penetrating the plate fin is formed, and the air to be cooled is passed through the exposed pipe portion and each of the directions in the direction intersecting the arrangement direction of the plate fin. It flows along the heat exchange path passing between the plate fins, and the moisture contained in the air to be cooled adheres to the outer peripheral surface portion of the exposed tube portion as frost.

  In the present invention, in order to attach a lot of frost to the exposed tube portion, a plurality of auxiliary plate fins are arranged at a wider interval than the plate fin, and the exposed tube portion is penetrated by these auxiliary plate fins. It is preferable that the moisture contained in the air to be cooled adheres as frost to the outer peripheral surface portion of the exposed tube portion and the surface portion of the auxiliary plate fin.

  According to the present invention, the refrigerant pipe includes the exposed pipe portion at the refrigerant inlet portion where the temperature is lowest when the refrigerant flows in. Therefore, the temperature of the exposed tube portion is lower than that of the plate fin. Since frost has a property of adhering to a lower temperature portion, frost generated when the air to be cooled passes through the heat exchange path adheres to the exposed pipe portion. As a result, frost can be prevented from adhering to the plate fins, so that clogging occurs between the plate fins even when the evaporator is operated for a long time in an environment where moisture outside air flows in. Can be avoided. Therefore, the cooling capacity of the evaporator does not decrease due to frost adhesion. Further, since the heat exchange path is not closed due to the attachment of frost, an abnormality such as a decrease in atmospheric pressure occurs in the air cooler equipped with the evaporator, and the apparatus is not stopped.

  Hereinafter, an evaporator to which the present invention is applied will be described with reference to the drawings. FIG. 1 is an explanatory view schematically showing main components of the evaporator of this example. (a) is a schematic front view, (b) is a schematic perspective view.

  As shown in FIG. 1, the evaporator 1 includes left and right side plates 2 and 3, a plurality of plate fins 4 arranged at a predetermined interval between the side plates 2 and 3, and a plurality of refrigerant tubes 5. have. The plate fins 4 have a rectangular outline, and many are arranged at narrow intervals in order to increase the heat transfer area from the refrigerant flowing through the refrigerant pipe 5. The arrangement direction A is orthogonal to the heat exchange path B through which the air to be cooled flows.

  Each refrigerant pipe 5 is made of copper, and is formed in the refrigerant inlet portion 51 into which the refrigerant flows and the refrigerant inlet portion 51, and is routed along the arrangement direction A of the plate fins 4 without penetrating the plate fins 4. The exposed pipe portion 52, the meandering pipe portion 53 that passes through the plate fin 4 and is drawn in a meandering state following the exposed pipe portion 52, and the refrigerant outlet portion 54 that discharges the refrigerant.

  The refrigerant inlet portion 51 is attached to the upper end portion of the right side plate 2. The exposed pipe portion 52 continuing from the refrigerant inlet portion 51 is drawn in a meandering state above (outside) the upper end surface (first end surface) 4 a of the plate fin 4. The serpentine tube portion 53 that follows is drawn from the upper end surface (first end surface) 4a of the plate fin 4 toward the lower end surface (second end surface) 4b. The exposed tube portion 52 and the meandering tube portion 53 are fixed to the side plates 2 and 3 with portions close to the left and right bent ends penetrating the left and right side plates 2 and 3, respectively. The refrigerant outlet portion 54 is attached to the lower end portion of the right side plate 2.

  In the evaporator 1 of this example, the refrigerant sent from a condenser (not shown) is distributed to each refrigerant pipe 5 by the flow divider 6 and flows into the refrigerant inlet portion 51. The refrigerant that has flowed first flows through the exposed pipe portion 52, and then flows through the meandering pipe portion 53 from the upper end surface 4 a to the lower end surface 4 b of the plate fin 4. While the refrigerant flows through the refrigerant pipe 5, the refrigerant exchanges heat with the air flowing through the heat exchange path B passing between the exposed pipe portion 52 and the plate fin 4, and cools the air. Thereafter, the refrigerant is discharged from the refrigerant outlet portion 54 and sent to the compressor (not shown) through the recovery pipe 7.

  Here, since the exposed tube portion 52 is formed following the refrigerant inlet portion 51 whose temperature is lowest when the refrigerant flows, the temperature of the exposed tube portion 52 is lower than that of the plate fin 4. Since the frost has a property of adhering to a lower temperature portion, the frost generated when the air to be cooled passes through the heat exchange path B adheres to the exposed pipe portion 52.

  According to this example, since the frost generated in the evaporator 1 adheres to the exposed pipe portion 52, the adhesion of frost to the plate fin 4 can be suppressed. Therefore, it is possible to avoid clogging between the plate fins 4 even when the evaporator 1 is operated for a long time in an environment in which outside air containing moisture flows. Therefore, the cooling capacity does not decrease due to frost adhesion. In addition, since the heat exchange path B is not closed due to adhesion of frost, an abnormality such as a decrease in atmospheric pressure is caused in the air cooler equipped with the evaporator 1 of this example, and the apparatus is stopped. There is no end.

  Further, according to this example, the refrigerant pipe 5 is drawn in a meandering state from the upper end face 4 a to the lower end face 4 b of the plate fin 4, and the exposed pipe portion 52 is formed on the upper end face 4 a of the plate fin 4. It is arranged above. The temperature on the upper end surface 4a side of the plate fin 4 on the upstream side of the refrigerant flow path in the refrigerant tube 5 is lower than the temperature on the lower end surface 4b side, and an exposed tube portion 52 is provided in this portion. Therefore, frost tends to adhere to the exposed tube portion 52. Further, since the exposed pipe portion 52 is located above the upper end surface 4a of the plate fin 4, even if frost adheres thereto, the flow of air passing between the plate fins 4 is not hindered. .

  Furthermore, since the exposed tube portion 52 is drawn in a meandering state so as to increase its surface area, a large amount of frost can be attached to the exposed tube portion 52.

  The evaporator 1 of this example is installed such that the arrangement direction A of the plate fins 4 is the horizontal direction and the exposed pipe portion 52 is on the upper side, but the installation of the evaporator 1 is limited to this state. It is not something. For example, it may be installed upside down so that the exposed tube portion 52 faces down. Further, the exposed tube portion 52 may be installed so as to face the heat exchange path B. Further, the plate fins 4 may be installed such that the arrangement direction A is a vertical direction. In this case, the exposed tube portion 52 may be disposed on either side in the horizontal direction.

(Modification of the above form)
Next, an example in which a plate fin is attached to the exposed tube portion in the above evaporator will be described. FIG. 2 is an explanatory view schematically showing main components of the evaporator of this example. (a) is a schematic front view, (b) is a schematic perspective view. In addition, since the same structure as said example is provided except the shape of a part plate fin and the structure of an exposed pipe part, the same code | symbol is attached | subjected to a corresponding structure and the description is abbreviate | omitted.

  In the evaporator 1A of the present example, among the plurality of arranged plate fins 4, plate fins arranged every predetermined number are formed into vertically long plate fins 4A. Further, in the vertically long plate fin 4 </ b> A, the exposed pipe portion 52 is penetrated through a fin portion (auxiliary plate fin) 40 protruding upward from the upper end surface 4 a of the other plate fin 4.

  According to this example, since the surface area of the exposed tube portion 52 can be increased by the fin portion 40, a lot of frost can be attached to the exposed tube portion 52 and the fin portion 40. As a result, the adhesion of frost to the plate fins 4 can be suppressed over a long period of time, so that even when the evaporator 1 is operated for a long time in an environment in which outside air containing moisture flows in, the plate It is possible to avoid clogging between the fins 4.

  Instead of the plate fins 4A, a plurality of auxiliary plate fins that are configured separately from the plate fins 4 are prepared, and these auxiliary plate fins are spaced apart from the plate fins 4 at the upper end surface of the plate fins 4. It may be arranged above 4a, and the exposed tube portion 52 may be led through these auxiliary plate fins.

(Other embodiments)
In the above example, all of the exposed tube portions 52 are formed above the upper end surface 4a of the plate fin 4, but the arrangement of the exposed tube portions 52 is not limited to this. FIG. 3 shows an arrangement example of the exposed tube portion.

  3 (a) and 3 (b), the exposed pipe portion 52 has one end face 4c orthogonal to the upper end face (first end face) 4a and the lower end face (second end face) 4b of the plate fin 4 having a rectangular outline, 4d is arranged outside the end faces 4c and 4d. In (a), the exposed pipe portion 52 is arranged on the upstream side of the heat exchange path B from the plate fin 4, and in (b), the exposed pipe portion 52 is arranged on the downstream side of the heat exchange path B from the plate fin 4. Has been.

  FIG. 3 (c) shows a first plate fin group 41 arranged at a predetermined interval and a second plate fin group 42 arranged at a predetermined interval as plate fins arranged at a predetermined interval. And the first plate fin group 41 and the second plate fin group 42 have a configuration in which they are arranged at a predetermined distance in a direction orthogonal to the arrangement direction (plate fin arrangement direction) A of the plate fins constituting them. I have. The first plate fin group 41 and the second plate fin group 42 are routed with the meandering pipe portion 53 penetrating therethrough. The exposed tube portion 52 is drawn in a meandering state between the first plate fin group 41 and the second plate fin group 42.

  In any case, the refrigerant flowing into the refrigerant pipe 5 first flows from the refrigerant inlet part 51 through the exposed pipe part 52 and then through the meandering pipe part 53. Therefore, since the temperature of the exposed tube portion 52 is lower than the temperature of the plate fin 4, the generated frost can be attached to the exposed tube portion 52, and adhesion to the plate fin 4 can be suppressed. In any example, auxiliary plate fins arranged at a wider interval than the plate fins 4 can be attached to the exposed tube portion 52.

It is the schematic front view and schematic perspective view for demonstrating the evaporator to which this invention is applied. It is the schematic front view and schematic perspective view for demonstrating the evaporator which attached the plate fin to the exposed pipe part. (A) and (b) are examples of the arrangement of the exposed tube portions, wherein the exposed tube portions are arranged along one end surface orthogonal to the first end surface and the second end surface of the plate fin having a rectangular outline. It is an example arrange | positioned on the outer side, (c) is the 1st plate fin group arranged at the predetermined interval as the plate fin arranged at the predetermined interval, and the second arranged at the predetermined interval. It is an example which has a plate fin group and the exposure pipe | tube part is arrange | positioned between the 1st plate fin group and the 2nd plate fin group.

Explanation of symbols

1, 1A Evaporator 4, 4A Plate fin 5 Refrigerant pipe 6 Divider 7 Recovery pipe 51 Refrigerant inlet part 52 Exposed pipe part 53 Meander pipe part 54 Refrigerant outlet part A Plate fin arrangement direction B Heat exchange path

Claims (7)

A plurality of plate fins arranged at predetermined intervals;
A refrigerant pipe drawn through these plate fins, and
An exposed pipe portion that is formed in the refrigerant inlet portion of the refrigerant pipe and is routed along the arrangement direction of the plate fins without penetrating the plate fins;
A heat exchange path through which air to be cooled flows between the plate fins and via the exposed pipe portion,
The evaporator is characterized in that the exposed tube portion is disposed outside the plate fin. In claim 1,
The plate fin has a rectangular outline,
From the first end face side of the plate fin, toward the second end face facing the first end face, the refrigerant pipe is drawn in a meandering state,
The evaporator is characterized in that the exposed pipe portion is disposed outside the first end face along the first end face of each plate fin. In claim 1,
The plate fin has a rectangular outline,
From the first end face side of the plate fin, toward the second end face facing the first end face, the refrigerant pipe is drawn in a meandering state,
The evaporator is characterized in that the exposed pipe portion is disposed outside the end face along one end face perpendicular to the first end face and the second end face of the plate fin. In claim 1,
As the plate fins arranged at a predetermined interval, a first plate fin group arranged at a predetermined interval, and a second plate fin group arranged at a predetermined interval,
The first plate fin group and the second plate fin group are separated by a predetermined distance in a direction perpendicular to the plate fin arrangement direction,
The evaporator is characterized in that the exposed tube portion is disposed between the first plate fin group and the second plate fin group. In any one of claims 1 to 4,
Auxiliary plate fins arranged at a wider interval than the plate fin interval,
The evaporator is characterized in that the exposed pipe portion is drawn through the auxiliary plate fins. A predetermined length routed in the arrangement direction of the plate fins without penetrating these plate fins into the refrigerant inlet portion of the refrigerant pipe routed through the plurality of plate fins arranged at predetermined intervals Forming the exposed tube part,
The air to be cooled is caused to flow along a heat exchange path passing between the exposed pipe portion and each plate fin in a direction crossing the arrangement direction of the plate fins,
A method for preventing frost formation in an evaporator, wherein moisture contained in air to be cooled is attached as frost to an outer peripheral surface portion of the exposed pipe portion. In claim 6,
Arranging a plurality of auxiliary plate fins at wider intervals than the plate fins,
Pull the exposed pipe part through the auxiliary plate fins,
A method for preventing frost formation in an evaporator, wherein moisture contained in air to be cooled is attached as frost to the outer peripheral surface portion of the exposed tube portion and the surface portion of the auxiliary plate fin.

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