Patent Application
20050092473
The present invention relates to heat exchangers, and more particularly to universal fins that can be used in fin on tube heat exchangers.
Heat exchangers are used in a wide variety of applications and come in a wide variety of configurations to fit these various applications. One particular application in which heat exchangers are used is as condensers in refrigeration cabinets. The condensers in the refrigeration cabinets can come in a variety of configurations. When a condenser is installed underneath the refrigeration cabinet, the heat exchanger is generally a wire-on-tube condenser. These condensers underneath the refrigeration cabinet have a much larger horizontal dimension then vertical dimension, assuming a horizontal air flow. When the condensers are installed in the machine compartment of the refrigeration cabinet, the condensers will have a larger vertical dimension than horizontal dimension, assuming a horizontal air flow. Because these condensers have a larger vertical dimension then horizontal dimension, the configuration of these condensers is typically that of a jelly-roll condenser or a multi-layer wire-on-tube configuration. Therefore, the configuration of the condenser in a refrigeration cabinet can vary depending on whether the condenser is positioned underneath the refrigeration cabinet or within a machine compartment of the cabinet.
Because the configurations vary, a manufacturer of refrigeration cabinets must have available a variety of heat exchanger configurations dependent on where the condenser is to be placed. In an effort to simplify the manufacturing process and to reduce cost, it would be desirable to have a common condenser configuration that can be used in either location. It would be further desirable if the common condenser configuration can utilize a universal fin that could be cut or separated to form one or more fins for either configuration regardless of the vertical or horizontal dimensions of the condenser configuration.
In domestic refrigerators, heat exchangers are used to form both evaporators and condensers. When the heat exchangers are configured to be evaporators in domestic refrigerators, they have a relatively small inlet for air and a comparably long air path through the evaporator. That is, assuming a vertical airflow, the evaporators are configured to have a much larger vertical dimension than horizontal dimension.
The heat exchangers that are typically configured to perform as either evaporators or condensers for domestic refrigerators use a tube and fin pattern that is different depending upon whether the heat exchangers are configured as evaporators or condensers. The different configurations do not allow for the use of a common fin to make the heat exchangers. Therefore, a manufacturer of these heat exchangers must maintain not only different configurations but also a variety of fin patterns that can be used on the differing configurations of the heat exchangers. It would be desirable if the configurations of the heat exchangers were similar enough that a universal or common fin pattern could be used to provide fins for the heat exchanger regardless of whether the heat exchangers are configured as condensers or as evaporators. The use of a universal or common fin pattern will reduce the cost of manufacturing the heat exchanger by reducing the variety of fins the manufacturer of heat exchangers will be required to produce and/or stock and reducing the capital investment required to purchase and maintain stamping dies for each different fin pattern.
Therefore, it would be desirable to provide a heat exchanger that can be configured with either a larger number of tube passes parallel to the airflow or tube passes perpendicular to the airflow and that will utilize the same universal or common fin pattern. The use of a common or universal fin pattern thereby reduces the cost to manufacture and provide heat exchangers of varying configurations. Additionally, it would be desirable if the tube pattern were such that the tube passes were oriented relative to the airflow for an optimal or highly efficient heat transfer.
The present invention allows for the construction of heat exchangers that can be configured as either evaporators or condensers and utilize a common or universal fin regardless of the number of vertical and horizontal tube passes in the heat exchangers. A universal fin for use in a fin on tube heat exchanger according to the principles of the present invention includes a sheet of heat conducting material that is configured to be separated to form one or more fins for use on the fin on tube heat exchanger regardless of a number of vertical and horizontal pairs of tubing segments in the heat exchanger. The sheet has a width and a height. There are a plurality of openings in the sheet. Each of the openings is configured to allow a pair of generally parallel tubing segments of the heat exchanger to pass therethrough. The openings are canted relative to the width and height of the sheet. The openings are arranged on the sheet into a plurality of rows and a plurality of columns with adjacent rows being generally equally spaced apart and adjacent columns being generally equally spaced apart. The spacing between adjacent rows and adjacent columns is dimensioned to allow the sheet to be separated between at least one of the adjacent rows and the adjacent columns to form one or more fins that each contain a plurality of openings at least equal to a number of pairs of tubing segments in the heat exchanger.
A fin on tube heat exchanger having a fin formed from a universal fin sheet is also disclosed. The heat exchanger includes a tube portion having a plurality of straight segments of tubing interconnected by a plurality of connecting segments of tubing with each connecting segment interconnecting two straight segments. The straight and connecting segments are arranged in a sinuous configuration. The tube portion has a known quantity of vertical and horizontal pairs of tube passes. There is at least one fin on the tube portion. The fin is separated from a universal fin sheet having a width, a height and a plurality of openings with each opening configured to allow a pair of tube passes to pass therethrough. The openings are arranged on the universal fin sheet into a plurality of rows and a plurality of columns with adjacent rows being generally equally spaced apart and adjacent columns being generally equally spaced apart. The spacing between adjacent rows and adjacent columns is dimensioned so that the universal fin sheet can be separated between at least one of the adjacent rows and adjacent columns to form the fin having a quantity of openings at least equal to the number of pairs of tube passes regardless of a number of vertical and horizontal pairs of tube passes in the tube portion. The fin formed thereby has a quantity of openings at least equal to the number of pairs of tube passes in the tube portion and is arranged on the tube portion with each pair of tube passes of the tube portion passing through one of the openings in the fin.
The present invention also discloses a method of making a fin on tube heat exchanger. The method includes: (1) separating at least one fin having a predetermined quantity of openings from a preformed universal fin sheet that is configured to be separated to provide one or more fins for use on a heat exchanger regardless of a number of vertical and horizontal pairs of tube passes in a tube portion of the heat exchanger on which the at least one fin is to be used; and (2) positioning the fin on the tube portion of the heat exchanger with pairs of tube passes passing through the openings.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
FIGS. 8B-D are front elevation views of exemplary continuous fins that can be formed from the universal fin of
The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
Referring now to
Referring now to
The tube portion 30 has a plurality of horizontal and vertical tube passes 38. A tube pass 38 is defined as the part of the tube portion 30 that passes through a common opening 22 in a fin 28. The tube portion 30 will be configured for the specific application in which the heat exchanger 32 is desired to be used. That is, the number of vertical and horizontal tube passes 38 will vary depending upon the application in which the heat exchanger 32 formed from the tube portion 30 is to be used. For example, as shown in
Each tube pass 38 is comprised of a pair 40 of straight segments 34 which pass through all or a portion of the fins 28 on the heat exchanger 32. The two straight segments 34 are interconnected by a connecting segment 36. The straight segments 34 and the connecting segments 36 are formed into a sinuous or serpentine tube portion 30, as is known in the art, to be used in the heat exchanger 32. Preferably, each straight segment 34 that forms a pair 40 of straight segments are parallel to one another. Even more preferably, all the straight segments 34 that comprise tube passes 38 are generally parallel. A single straight segment 34 could also pass through all or a portion of each fin 28 on the heat exchanger 32.
Preferably, the tube portion 30 is configured so that adjacent horizontal tube passes 38 are uniformly spaced apart. Also preferably, adjacent vertical tube passes 38 are uniformly spaced apart. Even more preferably, the spacing between adjacent horizontal tube passes 38 is generally the same as the spacing between adjacent vertical tube passes 38. The uniform spacing between adjacent horizontal and vertical tube passes 38 enables the universal fin 20 to provide one or more fins 28 to be used with the tube portion 30 to form heat exchangers 32 regardless of the number of horizontal and vertical tube passes 38, as will be described in more detail below.
The tube portion 30 can be made in a variety of manners. For example, as shown in
Referring now to
As was stated above, the universal fin 20 is configured so that one or more fins 28 can be separated from the universal fin 20 and used on a heat exchanger 32 regardless of the number of horizontal or vertical tube passes 38 that comprise the heat exchanger 32. To enable the universal fin 20 to provide one or more fins 28 for use on a heat exchanger 32 regardless of the number of horizontal and vertical tube passes 38, the spacing between the openings 22 on the universal fin 20 generally need to be the same as the spacing between the tube passes 38 on a tube portion 30. Preferably, adjacent columns 24 of openings 22 are generally equally spaced apart. Also preferably, adjacent rows 26 of openings 22 are generally equally spaced apart. The tube portion 30 is configured so that the spacing between vertical tube passes 38 is generally the same as the spacing between adjacent rows 26 of openings 22 in the universal fin 20 and the spacing between horizontal tube passes 38 is generally the same as the spacing between adjacent columns 24 of openings 22 in the universal fin 20.
Because the tube portion 30 is configured so that the spacing between vertical and horizontal tube passes 38 are the same as the spacing between the columns 24 and the rows 26, the universal fin 20 can be separated between the rows 26 and/or columns 24 to form one or more continuous fins 28 that can be used on the tube portion 30 to form a heat exchanger 32 regardless of the number of horizontal and vertical tube passes 38. For example, when the tube portion 30 is configured into the shape shown in
Preferably, the universal fin 20 is separated so as to form a plurality of continuous fins 28 having the same number of columns 24 and rows 26 so that the plurality of fins 28 can be aligned to form a fin bank 50 through which the tube passes 38 of the tube portion 30 pass. That is, the plurality of fins 28 formed from a universal fin 20 are positioned on the tube portion 30 and spaced along the tube passes 38 to form an efficient heat exchanger 32. It should be appreciated that the universal fin 20 can be separated so as to form continuous fins 28 having more or less number of columns 24 and/or rows 26 than the number of horizontal and/or vertical tube passes 38 if desired and still be within the scope of the present invention.
Optionally, to facilitate the separation of the universal fin 20 to form one or more continuous fins 28, the universal fin 20 can be provided with indicia 51 that extends between the adjacent columns 24 and/or between adjacent rows 26. The indicia 51 indicates locations on the universal fin 20 where the universal fin 20 can be separated to form the one or more fins 28. The indicia 51 can be perforations in the universal fin 20. The perforations facilitate the separating of the one or more fins 28 from the universal fin 20.
The one or more continuous fins 28 formed from the universal fin 20 are assembled on the tube portion 30 by either sliding the tube passes 38 through the openings 22 until the fins 28 are positioned in desired locations on the tube portion 30, or by sliding the fins 28 along the tube passes 38 until the fins 28 are located at desired positions on the tube portion 30. The fins 28 can then be secured to the tube portion 30, by a variety of methods. Preferably the fins 28 are attached to the tube portion by a mechanical or interference fit. The openings 22 can be configured so that the end portions 48 deform slightly as a result of the tube passes 38 extending through the openings 22. The deformation of the end portions 48 mechanically retain the fins 28 at desired locations on the tube portion 30 and provide good surface contact between fins 28 and tube portion 30. Alternatively, other methods of attaching the fins 28 to the desired location of the tube portion 30, such as by brazing and/or adhesives, may be employed.
The one or more continuous fins 28 that are made from the universal fin 20 can be separated from the universal fin 20 in a variety of ways. For example, the universal fin 20 can be cut between adjacent rows 26 and/or adjacent columns 24 to form the one or more fins 28 having a desired number of columns 24 and rows 26 of openings 22. Other methods of separating the universal fin 20 between the columns 24 and/or rows 26, as will be apparent to those skilled in the art, can also be employed without departing from the scope of the invention as defined by the claims.
The universal fin 20 can be formed by a variety of methods, as will be apparent to those skilled in the art. For example, as shown in
As was mentioned above, the configuration of the tube portion 30 in a heat exchanger 32 will vary depending upon the application in which the heat exchanger 32 is desired to be used. For example, when the heat exchanger 32 is desired to be used in a domestic refrigerator, the heat exchanger 32 can be configured to be either an evaporator 56 or a condenser 58. When heat exchanger 32 is configured to be a condenser 58 for application in a machine compartment, the heat exchanger 32 will have a general shape as shown in
The tube portion 30 can also be configured so the heat exchanger 32 takes the form of an evaporator or a condenser 56 for application underneath a refrigerator. The evaporator or condenser 56 is characterized having a relatively small inlet for air flow and a comparably long path through the evaporator or condenser 56 through which the air flows. Therefore, as can be seen in
Optionally, but preferably, the spacing between adjacent columns 24 is generally equal to the spacing between adjacent rows 26. When the spacing between adjacent columns 24 and adjacent rows 26 is the same, the tube portion 30 which is configured to use one or more continuous fins 28 from the universal fin 20 has the vertical and horizontal tube passes 38 also equally spaced apart and equal to the spacings between the adjacent columns 24 and adjacent rows 26. The tube portion 30 can then utilize the universal fin 20 to provide one or more continuous fins 28 to be assembled with the tube portion 30 to form a heat exchanger 32 having any desired number of vertical and horizontal tube passes 38.
Referring now to
The partial overlapping of an opening 22′ in one column 24′ with an opening 22′ in an adjacent column 24′ allows for closer spacing between tube passes 38′ in a heat exchanger 32′ formed with scalloped fins 28′, such as the heat exchanger 32′ shown in
As will be apparent to those skilled in the art, the universal fin 20 can be used to provide one or more continuous fins 28, 28′ for a variety of configurations of a heat exchanger 32, 32′ that has horizontal and vertical tube passes that are spaced apart generally equal to the spacings between the columns 24, 24′ and rows 26, 26′ of openings 22, 22′ in the universal fin 20, 20′. Therefore, while the universal fin 20, 20′ has been shown as being able to provide one or more continuous fins 28, 28′ for use in a 2×8 configuration and an 8×4 configuration, it should be understood that universal fin 20, 20′ can be used to provide fins 28, 28′ for n×n configurations, where n is a positive integer, without departing from the scope of the invention as defined by the claims.
The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.
