JP2015215141A - Heat exchanger and cooling system using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an economical heat exchanger which achieves a reduction in mold cost, which achieves improvement of heat exchange efficiency and defrosting efficiency and energy saving, and which can perform improvement of process quality, and a cooling system using the same.SOLUTION: A heat exchanger includes DB plate fins 3 independent at least at every two rows of refrigerant tubes, and FB plate fins 4 independent at every two rows of the refrigerant tubes, and it is configured so that the plurality of DB plate fins and FB plate fins are arranged by mutually having intervals. Thereby, as the heat exchanger is not divided at every two rows even for a specification of equal to or greater than four rows, the heat exchanger can retain the shape and core strength is enhanced. Also, by arranging the FB plate fins 4 in a straight pipe part 2a in which the DB plate fins 3 are difficult to arrange, the risk of rupture of hydraulic pipe expansion can be avoided. Also, heat conduction between rows can be facilitated and defrosting efficiency improves. Furthermore, boundary layer front edge effect, which is an advantage of independent fins, is maintained, so that cost performance becomes high.

Description

  The present invention relates to a heat exchanger used as a cooler (evaporator) in a household or commercial refrigerator, a showcase, and the like, and a cooling system using the heat exchanger.

  In recent years, for example, home refrigerators tend to fix the outer dimensions of the main body and increase the internal capacity, and as a result, cooling system-related parts are required to be more compact year by year. In commercial refrigerators as well, energy-saving models have become fully available, and as a result, there is a need for higher efficiency in cooling system-related parts.

  Under such circumstances, there is an increasing demand for compactness and high efficiency of heat exchangers.

  On the other hand, the demand for rationalization of component materials has increased due to soaring raw materials, and in addition to improving the performance of heat exchangers, there has been a demand for rationalization of thin materials.

  As an example, a dockbone (DG) type heat exchanger, that is, a serpentine-like refrigerant tube inserted into a so-called dogbone type long hole processed into a plate fin, and an economical aluminum pipe A dock bone type heat exchanger that can be used and has a high efficiency element is known (see, for example, Patent Document 1 and Patent Document 2).

  9 to 11 show conventional heat exchangers described in Patent Document 1 and Patent Document 2 described above.

  FIG. 9 is a front view of a conventional heat exchanger, and FIG. 10 is a side view of the heat exchanger.

  The conventional heat exchanger 101a includes a refrigerant tube 102 that is bent in a meandering manner at a predetermined pitch so that a plurality of rows and stages are formed continuously in a straight pipe portion and a curved pipe portion, a rectangular portion, and the rectangular portion. A plurality of long holes 105 made of circular arc portions provided on the short sides on both sides of the portion are provided on the center surface of the plate. Furthermore, it includes a DB plate fin 103a that is independent for at least two rows of refrigerant tubes, and a DB end fin 103b that is provided with a plurality of long holes 105 on the center surface of the plate and integrated with at least four rows of refrigerant tubes. . A plurality of DB plate fins 103a are arranged with a space therebetween, and the DB end fins 103b are arranged in the vicinity of the curved pipe portion of the refrigerant tube 102, and the refrigerant tube 102 is fixed through the long hole 105. . In the through-fixing method, the refrigerant tube 102 is expanded in diameter by a hydraulic pressure and is closely fixed to the arc portion of the long hole 105.

  The operation of the heat exchanger 101a configured as described above will be described below.

  First, since the DB plate fin 103a has a shape divided at least every two rows, the leading edge of the DB plate fin 103a appears many times in the row direction, that is, the air flow direction, and the heat transfer coefficient is maximized. It becomes. The conventional heat exchanger 101a is improved in efficiency by the boundary layer leading edge effect.

In addition, since the refrigerant tube 102 is expanded by hydraulic pressure and closely fixed to the arc portion of the long hole 105, a plurality of DB plate fins 103a arranged due to variations in the tube diameter accuracy and bending accuracy of the refrigerant tube 102 are provided. Even when there is a portion where the contact state between the refrigerant tube 102 and the long hole 105 is deteriorated when penetrating into the long hole 105, the variation is absorbed and the refrigerant tube 1 is absorbed.
The adhesion between 02 and the long hole 105 can be improved. That is, high efficiency is achieved by reducing the contact thermal resistance between the refrigerant tube 102 and the DB plate fin 103a.

  In addition, by using these high efficiency elements, the material cost may be rationalized by downsizing the heat exchanger 101a or thinning the fin material.

  Further, the DB end fins 103b are arranged in the vicinity of the bent tube portion of the refrigerant tube 102, and the refrigerant tubes 102 are fixedly passed through the long holes 105, so that the shape of the heat exchanger in four or more rows can be maintained. The configuration having only 103a solves the disadvantage that the shape of the heat exchanger 101a cannot be fixed because the shape is divided every two rows.

  On the other hand, in order to improve the defrosting characteristics and promote energy saving, the so-called dogbone heat exchanger appropriately includes independent plate fins in at least two rows and plate fins integrated in at least four rows. A method of mixing is known (see, for example, Patent Document 3).

  FIG. 11 shows a conventional heat exchanger described in Patent Document 3. As shown in FIG.

  The conventional heat exchanger 101b shown in FIG. 11 is a so-called dogbone type heat exchanger, and four or more rows of meandered refrigerant tubes 102, and at least two independent DB plate fins 103a for each of the refrigerant tubes, DB end fins 103b integrated with at least four rows of refrigerant tubes are provided. A plurality of DB plate fins 103a and a plurality of DB end fins 103b are arranged at a specific ratio and spaced apart from each other, and the refrigerant tube 102 is fixed through the long hole 105. At this time, the defrosting heater 114 is arrange | positioned under the heat exchanger 101b.

  The operation of the heat exchanger 101b configured as described above will be described below.

  First, since the DB plate fin 103a has a shape divided at least every two rows, the front edge of the DB plate fin 103a appears many times in the row direction, that is, the air flow direction, and the heat transfer coefficient is maximized. . That is, like the above-described conventional heat exchanger 101a, the conventional heat exchanger 101b is also highly efficient due to the boundary layer leading edge effect. That is, since the DB plate fins 103a are divided into at least two rows, the heat transfer area in the same arrangement space is smaller than that of the DB end fins 103b integrated in at least four rows, but the drawbacks thereof are Higher efficiency is achieved by the leading edge effect of the boundary layer.

  Therefore, considering the heat exchange efficiency as a cooler, if the heat exchanger is configured with only the DB plate fins 103a as much as possible, the cost performance increases.

  On the other hand, if a heat exchanger is comprised only with DB plate fin 103a, the heat conduction from the lower part to the upper part at the time of defrosting will be bad, and defrosting efficiency will fall. However, by mixing the DB end fins 103b at a specific ratio as described above, the defrosting efficiency can be improved without reducing the heat exchange efficiency. That is, the heat of the defrost heater 114 disposed at the lower part of the heat exchanger 101b can be transferred to the DB end fin 103b and directly conducted to the upper part. Therefore, not only the defrosting efficiency is improved, but also by increasing the DB end fins 103b, the improvement in the heat exchange efficiency due to the increase in the heat transfer area and the decrease in the heat exchange efficiency due to the decrease in the leading edge are offset. However, by generating with a specific mixing ratio, the defrosting efficiency can be improved without reducing the heat exchange efficiency.

Japanese Patent Laid-Open No. 04-086491 JP 2007-093036 A JP 2010-261678 A

  However, in the former former heat exchanger 101a configuration, when the heat exchanger has a specification of four or more rows, the DB plate fins 103a are divided into at least two rows, so that the heat exchanger 101a has two rows. The shape cannot be maintained as a heat exchanger unless the position is fixed with some fixing tool. Therefore, the DB end fin 103b is used to hold the shape. However, since the DB end fin 103b is larger than the DB plate fin 103a, the processing mold becomes larger, and the size of the heat exchanger changes. Each had to have a mold and had the problem of increasing costs.

  In addition, when the straight tube portion length of the refrigerant tube 102 is different for each row, a portion where the refrigerant tube 102 cannot be fixed in contact with the arc portion of the DB plate fin 103a occurs, so there is a risk of rupture in the hydraulic pressure expansion process at that portion. Get higher. That is, when the diameter of the refrigerant tube 102 is increased by injecting liquid into the tube and pressurizing, the portion where the DB plate fin 103a is present is less likely to swell and the portion where the DB plate fin 103a is not present is slightly swelled, so there is a large variation in tube expansion. In special conditions such as the above, there is a possibility that the refrigerant tube 102 may rupture in the hydraulic expansion process. Therefore, there is a problem that the process quality is reduced, although it is slight.

  In the latter conventional heat exchanger 101a, when the heat exchanger has a specification of four or more rows, the DB plate fins 103a are divided into at least two rows, so that the heat exchanger 101a has two rows. The heat from the defrosting heater 114 installed in the lower part is hardly transmitted even though there is heat conduction by the DB end fin 103b. That is, there is a problem that the amount of power consumption is increased by slightly increasing the heating time. However, there are heat conduction from the refrigerant tube 102 and heat transfer by air, and the defrosting efficiency can be limited to a slight decrease depending on the number of DB end fins 103b.

  Further, in this configuration of the heat exchanger 101b, in order to further improve the defrosting efficiency, the mixing ratio of the DB end fins 103b may be increased. However, the ratio of the DB plate fins 103a is decreased, so that the boundary layer leading edge effect is obtained. However, there is a problem that the heat exchange efficiency is reduced.

  The present invention solves the above-mentioned conventional problems, compensates for the disadvantages of the independent fin type, reduces the mold cost, improves heat exchange efficiency and defrosting efficiency, saves energy, and improves process quality. An object of the present invention is to provide an economical heat exchanger that can be used and a cooling system using the heat exchanger.

  In order to solve the above-described conventional problems, the heat exchanger according to the present invention is a refrigerant in which a straight pipe portion and a curved pipe portion are formed in a meandering manner at a predetermined pitch so that a plurality of rows and stages are formed. A tube, a plurality of long holes made of a rectangular portion and circular arc portions provided on both short sides of the rectangular portion are provided in the center surface of the plate, and at least two DB plate fins independent for each two rows of the refrigerant tubes, a rectangular portion, and A plurality of semi-long holes made of circular arc portions provided on one short side of the rectangular portion are provided in the plate end surface, and at least two FB plate fins independent for each of the refrigerant tube rows, and the DB plate fin and the FB A plurality of plate fins are arranged with a space between each other, and the refrigerant tube is penetrated and fixed in the long hole and the semi-long hole.

  Thereby, by combining the DB plate fin and the FB plate fin, even when the refrigerant tube has a specification of four or more rows, the shape can be maintained and the core strength can be increased because it is not divided every two rows. Furthermore, since an extra large mold for DB end fins for penetrating and fixing four or more rows of refrigerant tubes is not required, the mold cost can be reduced. Further, even if the DB plate fin is a straight pipe portion that is difficult to place, it can be placed as long as it is an FB plate fin having a semi-long hole, thereby avoiding the risk of expanding the tube.

  If a defrost heater is provided at the lower part of the heat exchanger, the heat of the defrost heater is directly transmitted to the DB plate fin, the refrigerant tube, the FB plate fin, and the refrigerant tube. Is performed for the number of DB plate fins and FB plate fins, so that the heat conduction is greatly promoted and the defrosting efficiency is improved. Moreover, since the boundary layer leading edge effect, which is an advantage of the independent fin, is maintained, the cost performance is increased. Therefore, an economical heat exchanger that can compensate for the disadvantages of the independent fin type, reduce the mold cost, improve the heat exchange efficiency and defrosting efficiency, save energy, and improve the process quality is also used. A cooling system can be provided.

  The heat exchanger of the present invention and the cooling system using the same compensate for the disadvantages of the independent fin type, reduce the mold cost, improve the heat exchange efficiency and defrosting efficiency, save energy, and improve the process quality. It is also possible to provide an economical heat exchanger that can also be used and a cooling system using the heat exchanger.

The front view of the heat exchanger in Embodiment 1 of this invention Side view of the heat exchanger in the first embodiment Front view of DB plate fin in the first embodiment Front view of FB plate fin in the first embodiment Front view of heat exchanger according to Embodiment 2 of the present invention Front view of a heat exchanger according to Embodiment 3 of the present invention Front view of heat exchanger according to Embodiment 4 of the present invention Schematic diagram of the cooling system in the fourth embodiment Front view of conventional heat exchanger Side view of the heat exchanger Front view of another conventional heat exchanger

  According to a first aspect of the present invention, there is provided a refrigerant tube formed in a meandering manner at a predetermined pitch so that a plurality of rows and steps are continuously formed in a straight pipe portion and a curved pipe portion, and a rectangular portion and short sides on both sides of the rectangular portion. A plurality of long holes made of circular arc portions provided on the sides are provided in the center surface of the plate, and at least the DB plate fins independent for each two rows of the refrigerant tubes, and the circular arc portions provided on the rectangular portion and one short side of the rectangular portion A plurality of semi-long holes formed on the end face of the plate, and independent FB plate fins at least every two rows, and a plurality of the DB plate fins and the FB plate fins are arranged with a space between each other, The refrigerant tube is configured to pass through and be fixed to the long hole and the semi-long hole.

By combining such a configuration, that is, the DB plate fin and the FB plate fin, even when the refrigerant tube has a specification of four or more rows, it is not divided every two rows, so that the shape can be maintained and the core strength is increased. Furthermore, since no extra mold for DB end fins that penetrate and fix four or more rows of refrigerant tubes is required, the mold cost can be reduced. Therefore, a highly efficient and economical heat exchanger can be provided by making use of the characteristics of the independent fins. Further, even if the DB plate fin is a straight pipe portion that is difficult to place, it can be placed as long as it is an FB plate fin having a semi-long hole, thereby avoiding the risk of expanding the tube.

  If a defrost heater is provided at the lower part of the heat exchanger, the heat of the defrost heater is directly transmitted to the DB plate fin, the refrigerant tube, the FB plate fin, and the refrigerant tube. Is performed for the number of DB plate fins and FB plate fins, so that the heat conduction is greatly promoted and the defrosting efficiency is improved. Moreover, since the boundary layer leading edge effect, which is an advantage of the independent fin, is maintained, the cost performance is increased. Therefore, an economical heat exchanger that can compensate for the disadvantages of the independent fin type, reduce the mold cost, improve the heat exchange efficiency and defrosting efficiency, save energy, and improve the process quality is also used. A cooling system can be provided.

  According to a second aspect of the present invention, in the heat exchanger of the first aspect, the FB plate fin is arranged in a straight pipe portion where the DB plate fin of the refrigerant tube is difficult to arrange.

  By adopting such a configuration, as described in the first invention, the FB plate fin can be arranged in the straight pipe portion where the DB plate fin is difficult to arrange, thereby avoiding the risk of rupture of the hydraulic pressure expansion pipe. Therefore, an economical heat exchanger capable of improving process quality and improving yield can be provided.

  According to a third aspect of the present invention, in the heat exchanger of the first aspect, the straight pipe portion in which the DB plate fin of the refrigerant tube is difficult to arrange is processed and hardened.

  As a result, the bare pipe part of the straight pipe part is less likely to swell due to hydraulic pressure or the like than other straight pipe parts due to work hardening, so that the risk of expansion rupture can be avoided, the process quality can be improved, and the yield can be improved. An exchanger can be provided.

  According to a fourth aspect of the present invention, in the heat exchanger of the first aspect, the straight pipe portion in which the DB plate fin of the refrigerant tube is difficult to arrange is made smaller than the refrigerant tube diameter.

  As a result, the bare pipe part of the straight pipe part is reduced in diameter and is less likely to swell due to hydraulic pressure, etc. than other straight pipe parts, the risk of expanding pipe rupture can be avoided, process quality can be improved, and yield can be improved. An exchanger can be provided.

  According to a fifth aspect of the present invention, in the heat exchanger of the first to fourth aspects, the DB plate fin independent for each two rows of refrigerant tubes and the FB plate fin independent for every two rows of refrigerant tubes are DB plates. The fins are arranged in the row direction from the refrigerant tubes to the refrigerant tubes and from the refrigerant tubes to the FB plate fins.

  By adopting such a configuration, in addition to the effects of the first to fourth heat exchangers, the heat conduction between the rows described in the first invention, that is, to the DB plate fin, the refrigerant tube, the FB plate fin, and the refrigerant tube. Heat can be transmitted directly and continuously without interruption, and the defrosting efficiency can be further improved. Moreover, since the boundary layer leading edge effect, which is an advantage of the independent fin, is maintained, the cost performance is increased. Therefore, both the heat exchange efficiency and the defrosting efficiency can be improved, and an environment-friendly heat exchanger that can contribute to energy saving can be provided.

According to a sixth aspect of the present invention, there is provided a refrigerant tube formed in a meandering manner at a predetermined pitch so that a plurality of rows and steps are continuously formed in a straight pipe portion and a curved pipe portion, a rectangular portion, and short sides on both sides of the rectangular portion. The DB provided with a plurality of long holes made of circular arc portions provided on the side in the center surface of the plate, and provided with at least a DB plate fin independent for each two rows of the refrigerant tubes, and a plurality of the DBs arranged at intervals.
A heat exchanger in which the refrigerant tube is passed through and fixed to the long hole of the plate fin, and the straight pipe portion of the portion of the meandering refrigerant tube in which the DB plate fin is difficult to place is processed and hardened. It is a configuration.

  By adopting such a configuration, since the bare tube portion is work-hardened, it is difficult to swell due to the hydraulic pressure as compared with other straight tube portions, so that the risk of tube rupture can be avoided. Therefore, an economical heat exchanger capable of improving process quality and improving yield can be provided.

  According to a seventh aspect of the present invention, there is provided a refrigerant tube formed in a meandering manner at a predetermined pitch so that a plurality of rows and steps are continuously formed in a straight pipe portion and a curved pipe portion, a rectangular portion, and short sides on both sides of the rectangular portion. The DB provided with a plurality of long holes made of circular arc portions provided on the side in the center surface of the plate, and provided with at least a DB plate fin independent for each two rows of the refrigerant tubes, and a plurality of the DBs arranged at intervals. A heat exchanger in which the refrigerant tube penetrates and is fixed to the long hole of the plate fin, and the straight pipe portion of the portion of the meandering refrigerant tube where the DB plate fin is difficult to be arranged is smaller than the refrigerant tube diameter. The configuration is reduced.

  By adopting such a configuration, since the bare pipe portion of the straight pipe portion has a small diameter, it is difficult to swell due to the hydraulic pressure as compared with other straight pipe portions, and therefore, the risk of tube expansion burst can be avoided. Therefore, an economical heat exchanger capable of improving process quality and improving yield can be provided.

  An eighth invention is a cooling system comprising a compressor, a condenser, a pressure reducing device, an evaporator, and a defrosting heater disposed in a lower part of the evaporator, wherein the evaporator is first to seventh. This is a cooling system composed of any one of the heat exchangers.

  By adopting such a configuration, in addition to the effects of the present invention, the heat source of the defrost heater disposed at the lower portion can be efficiently transmitted to the upper portion, so that the defrost efficiency is also improved. In addition, since the boundary layer leading edge effect, which is an advantage of the independent fin, is also maintained, the cost performance is increased. Therefore, both the heat exchange efficiency and the defrosting efficiency can be improved, and an environment-friendly cooling system that can contribute to energy saving can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
1 is a front view of a heat exchanger according to Embodiment 1 of the present invention, FIG. 2 is a side view of the heat exchanger according to Embodiment 1, and FIG. 3 is a view of a DB plate fin according to Embodiment 1. FIG. 4 is a front view of the FB plate fin in the first embodiment.

  1 to 4, the heat exchanger 1 includes a refrigerant tube 2 that is bent in a meandering manner at a predetermined pitch so that a plurality of rows and steps are continuously formed in a straight pipe portion 2 a and a curved pipe portion 2 b. In addition, a plurality of long holes 5 each having a rectangular portion 5a and a circular arc portion 5b provided on both short sides of the rectangular portion 5a are provided on the center surface of the plate. Further, at least two rows of independent DB (DOG BONE, dogbone) plate fins 3 and a semi-long hole 6 consisting of a rectangular portion 6a and a circular arc portion 6b provided on one short side of the rectangular portion 6a are provided on the plate end surface. A plurality of FB (FIST BONE, fistbone) plate fins 4 are provided at least every two rows, and a plurality of DB plate fins 3 and FB plate fins 4 are arranged with an interval between each other. The refrigerant tube 2 is fixed through the 5 and the semi-long hole 6.

The refrigerant tube 2 is a pipe body in which refrigerant flows, and a straight pipe portion 2a and a curved pipe portion 2b are connected to one tube body made of aluminum or an aluminum alloy. A serpentine tube that is bent in a meandering manner in a zigzag manner in the (up and down) direction Y, and forms a single refrigerant flow path without using a connecting pipe that forms the curved pipe portion 2b.

  Generally, the lead pipe 7 and the accumulator 8 are joined to the inlet / outlet portion of the refrigerant tube 2, and the pipes constituting the cooling system are connected to the tip of the pipe, so that the lead pipe 7 and the accumulator 8 are installed. It is often processed into various shapes according to the shape of the side.

  About the heat exchanger 1 comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  First, the curved tube portion 2b of the refrigerant tube 2 is inserted into the plate center surface of the DB plate fin 3 independent every two rows, and is divided by two rows of blocks. Since the FB plate fins 4 are arranged so as to straddle the two rows of blocks, the shape can be maintained, and the rigidity of the heat exchanger 1 is increased. In addition, the shape can be maintained by using an undivided integrated plate fin such as the DB end fin 103b of the conventional heat exchanger 101a, but the DB end fin 103b is compared with the FB plate fin 4. Since it is large, the mold for processing also becomes large, and if the size of the heat exchanger changes, the mold must be held for each size, which increases the cost. However, if the FB plate fin shown in this embodiment is used, even if the heat exchanger size changes with one type of fin, it is possible to reduce the mold cost.

  Further, in the case of the arrangement state of the lead pipe 7 and the accumulator 8 as shown in FIG. 1, the DB plate fins 3 cannot be arranged in the straight pipe portion 2 a of the refrigerant tube 2 directly below them. In addition, when the length of the straight pipe portion 2a of the refrigerant tube 2 is shorter than the other rows due to the air path of the cooling system, the air volume distribution, the temperature / humidity distribution, the frost distribution, etc., the DB plate fins 3 cannot be disposed. A place occurs. Even if such a DB plate fin 3 is a straight pipe portion 2a that is difficult to place, it can be placed as long as it is an FB plate fin 4 provided with a semi-long hole 6. In this heat exchanger, the above DB The FB plate fin 4 is arranged in the straight pipe portion 2a where the plate fin 3 is difficult to arrange. This reduces the risk of rupture in the hydraulic expansion process. That is, when expanding the diameter of the refrigerant tube 2 by injecting liquid into the tube and pressurizing it, the location where the FB plate fins 4 are present is less likely to swell than the bare tube portion, so that there are special conditions such as large variations in tube expansion. In this case, the possibility that the refrigerant tube 2 is ruptured in the hydraulic expansion process can be reduced.

  As described above, in this heat exchanger, by combining the DB plate fins 3 and the FB plate fins 4, the shape can be maintained and the core strength can be increased because it is not divided every two rows even in the case of specifications of four rows or more. Further, since no extra mold is required, the mold cost can be reduced. Moreover, if the FB plate fins 4 are arranged in the straight pipe portion 2a where the DB plate fins 3 are difficult to arrange, the risk of rupture of the hydraulic pressure expansion pipe can be avoided.

  Moreover, if a defrost heater is provided in the lower part of this heat exchanger, the heat of this defrost heater will be directly transmitted to DB plate fin 3, refrigerant tube 2, FB plate fin 4, and refrigerant tube 2. Since the heat conduction is performed by the number of the DB plate fins 3 and the FB plate fins 4, the heat conduction is greatly promoted and the defrosting efficiency is improved. Moreover, since the boundary layer leading edge effect, which is an advantage of the independent fin, is maintained, the cost performance is increased. Therefore, an economical heat exchanger that can compensate for the disadvantages of the independent fin type, reduce the mold cost, improve the heat exchange efficiency and defrosting efficiency, save energy, and improve the process quality is also used. A cooling system can be provided.

  Therefore, it is possible to provide an economical heat exchanger that compensates for the disadvantages of the independent fin type in the dog bone type heat exchanger, reduces the mold cost, improves the process quality, and improves the yield.

(Embodiment 2)
FIG. 5 is a front view of the heat exchanger according to Embodiment 2 of the present invention. The same constituent elements as those in the first embodiment will be described with the same reference numerals.

  In FIG. 5, the heat exchanger 1 includes a refrigerant tube 2 that is bent in a meandering manner at a predetermined pitch so that a plurality of rows and stages are continuously formed in a straight pipe portion 2a and a curved pipe portion 2b, and a rectangular shape. A plurality of long holes 5 formed by arc portions 5b provided on the short sides on both sides of the portion 5a and the rectangular portion 5a are provided in the center surface of the plate, and at least two rows of independent DB plate fins 3 are provided. A plurality of DB plate fins 3 are arranged with a space between each other, the refrigerant tube 2 is passed through the long hole 5, and the diameter is expanded and fixed by the hydraulic pressure injected into the pipe of the refrigerant tube 2, Due to the shape of the refrigerant tube 2 bent in a meandering shape, a work hardening part 2c is provided in which the straight pipe part 2a where the DB plate fins 3 are difficult to place is work hardened before diameter expansion.

  The operation and action of the heat exchanger 1 configured as described above will be described below.

  First, in the arrangement state of the lead pipe 7 and the accumulator 8 as shown in FIG. 5, the DB plate fins 3 cannot be arranged in the straight pipe portion 2 a of the refrigerant tube 2 directly below them. In addition, when the length of the straight pipe portion 2a of the refrigerant tube 2 is shorter than the other rows due to the air path of the cooling system, the air volume distribution, the temperature / humidity distribution, the frost distribution, etc., the DB plate fins 3 cannot be disposed. A place occurs.

  If the straight tube portion 2a in which such DB plate fins 3 are difficult to place is provided with a work hardening portion 2c obtained by work hardening before diameter expansion, the risk of rupture in the hydraulic pressure expansion step is reduced.

  Examples of work hardening methods include twisting and bending back. By performing these processes on the work hardening part 2c before diameter expansion, the work hardening part 2c is less likely to swell, so that the risk of rupture in the hydraulic expansion process is reduced. That is, when expanding the diameter of the refrigerant tube 2 by injecting and pressurizing a liquid inside the tube, the work hardening portion 2c is less likely to swell than the straight tube portion 2a on which the DB plate fins 3 are arranged, so that the variation in tube expansion is large. In special conditions such as the above, it is possible to reduce the possibility of the refrigerant tube 2 bursting in the hydraulic expansion process.

  Thus, in this heat exchanger, since the bare pipe portion of the straight pipe portion 2a is work-hardened, it is difficult to swell due to the hydraulic pressure as compared with other straight pipe portions, and therefore the risk of bursting of the hydraulic expansion pipe can be avoided. Therefore, an economical heat exchanger capable of improving process quality and improving yield can be provided.

(Embodiment 3)
FIG. 6 is a front view of the heat exchanger according to Embodiment 3 of the present invention. The same constituent elements as those in the first embodiment will be described with the same reference numerals.

  In FIG. 6, the heat exchanger 1 includes a refrigerant tube 2 that is bent in a meandering manner at a predetermined pitch so that a plurality of rows and stages are continuously formed in a straight pipe portion 2a and a curved pipe portion 2b, and a rectangular shape. A plurality of long holes 5 formed by arc portions 5b provided on the short sides on both sides of the portion 5a and the rectangular portion 5a are provided in the center surface of the plate, and at least two rows of independent DB plate fins 3 are provided. A plurality of DB plate fins 3 are arranged with a space between each other, the refrigerant tube 2 is passed through the long hole 5, and the diameter is expanded and fixed by the hydraulic pressure injected into the refrigerant pipe, and the meandering shape Due to the shape of the bent refrigerant tube 2, the straight pipe portion where the DB plate fins 3 are difficult to place is a reduced diameter portion 2 d smaller than the diameter of the refrigerant tube 2.

  The operation and action of the heat exchanger 1 configured as described above will be described below.

  First, in the case of the arrangement state of the lead pipe 7 and the accumulator 8 as shown in FIG. 6, the DB plate fin 3 cannot be arranged in the straight pipe portion 2 a of the refrigerant tube 2 directly below them. In addition, when the length of the straight pipe portion 2a of the refrigerant tube 2 is shorter than the other rows due to the air path of the cooling system, the air volume distribution, the temperature / humidity distribution, the frost distribution, etc., the DB plate fins 3 cannot be disposed. A place occurs. If the straight pipe portion 2a in which the DB plate fins 3 are difficult to place is made smaller than the diameter of the refrigerant tube 2, the risk of rupture in the hydraulic pressure expanding step is reduced. As a method of reducing the diameter, there are a swaging process, a joining of a small diameter pipe, and the like.

  By forming the reduced diameter portion 2d by these methods before expanding the diameter, the reduced diameter portion 2d becomes difficult to expand, and the risk of rupture in the hydraulic pressure expanding step is reduced. That is, when the diameter of the refrigerant tube 2 is expanded by injecting and pressurizing the liquid inside the tube, the diameter-reduced portion 2d is less likely to swell than the straight tube portion 2a on which the DB plate fins 3 are arranged, and therefore, the variation in tube expansion is large. In special conditions such as the above, it is possible to reduce the possibility of the refrigerant tube 2 bursting in the hydraulic expansion process.

  Thus, in this heat exchanger, since the diameter of the bare pipe portion of the straight pipe portion 2a is reduced, it is difficult to swell due to liquid pressure as compared with other straight pipe portions, and the risk of rupture of the hydraulic pressure expansion pipe can be avoided. Therefore, an economical heat exchanger capable of improving process quality and improving yield can be provided.

  In addition, the heat exchanger of this Embodiment 3 and Embodiment 2 is as a method for connecting the independent DB plate fin 3 for every two rows, maintaining the shape of the heat exchanger 1, and improving the rigidity. The case where the DB plate fin 103b shown in the conventional example of FIG. 11 is used is illustrated. However, this may be replaced with the FB plate fin 4 described in the first embodiment to maintain the shape and improve the rigidity. By doing so, the same effect as described in the first embodiment is combined. Obtained.

(Embodiment 4)
FIG. 7 is a front view of the heat exchanger according to the fourth embodiment of the present invention, and FIG. 8 is a schematic diagram of the cooling system according to the fourth embodiment.

  7, in the heat exchanger 1 described in Embodiment 1, the heat exchanger 1 includes the DB plate fins 3 independent for every two rows and the FB plate fins 4 independent for every two rows. The DB plate fins 3 are appropriately arranged so as to conduct heat efficiently in the row direction from the refrigerant tube 2 to the refrigerant tube 2 and from the refrigerant tube 2 to the FB plate fin 4.

  In FIG. 8, this cooling system uses the heat exchanger 1 of FIG. 7 as an evaporator 12, and includes a compressor 9, a condenser 10, a decompression device 11, an evaporator 12, and an evaporator 12. The blower 13 arrange | positioned at the upper part and the defrost heater 14 arrange | positioned at the lower part of the evaporator 12 are provided.

  The operation and action of the heat exchanger configured as described above and the cooling system using the heat exchanger will be described below.

  First, in the heat exchanger 1, the DB plate fins 3 are arranged in the first and second rows from the bottom, and the FB plate fins 4 are arranged in the second and third rows. Similarly, the DB plate fins 3 are arranged in the third to fourth rows, the fifth to sixth rows, the seventh to eighth rows, and the ninth to tenth rows, and the fourth to fifth rows, the sixth to seventh rows, and the eighth to ninth rows. FB plate fins are arranged in the rows. Further, the DB plate fins 3 and the FB plate fins 4 are alternately arranged in a good balance in the left-right direction of the heat exchanger 1.

  Therefore, in the cooling system of FIG. 8 incorporating this heat exchanger 1, heat from the defrost heater 14 disposed at the lower part of the heat exchanger 1 can be efficiently conducted to the upper part.

That is, as described in the first embodiment, the heat from the defrost heater 14 is directly transmitted to the DB plate fin 3, the refrigerant tube 2, the FB plate fin 4, and the refrigerant tube 2, and the heat conduction. Is performed by the number of the DB plate fins 3 and the FB plate fins 4, so that it is greatly promoted and the defrosting efficiency is improved. In particular, in this embodiment, the DB plate fin 3 and the FB, such as the DB plate fin 3 in the first and second rows, the FB plate fin 4 in the second and third rows, and the DB plate fin 3 in the third and fourth rows. Plate fins 4 are arranged alternately. Thereby, the heat transmitted directly to the DB plate fin 3, the refrigerant tube 2, the FB plate fin 4, and the refrigerant tube 2 can be continuously and reliably conducted without interruption, and the defrosting efficiency is further improved. Can be improved.
Moreover, since the boundary layer leading edge effect, which is an advantage of the independent fin, is maintained, the cost performance is increased. Therefore, both the heat exchange efficiency and the defrosting efficiency can be improved, and an environment-friendly heat exchanger and cooling system that can contribute to energy saving can be provided.

  In addition, in this Embodiment 4, although the case of the cooling system incorporating the heat exchanger shown in FIG. 7 was demonstrated, it is good also as a cooling system incorporating the heat exchanger shown in Embodiment 1, 2, 3, In this case, it can be set as the cooling system which has the effect which each said heat exchanger has.

  The heat exchanger of the present invention and the cooling system using the same compensate for the drawbacks of the independent fin type in the dogbone heat exchanger, reduce the mold cost, improve the heat exchange efficiency and defrosting efficiency, and save energy. Since it is economical and can improve process quality, it can be widely used as a refrigerator or a radiator of refrigeration equipment ranging from household use to industrial use such as refrigerators and vending machines.

DESCRIPTION OF SYMBOLS 1 Heat exchanger 2 Refrigerant tube 2a Straight pipe part 2b Curved pipe part 2c Work hardening part 2d Reduced diameter part 3 DB plate fin 4 FB plate fin 5 Long hole 5a Rectangular part 5b Arc part 6 Semi-long hole 6a Rectangular part 6b Arc part 7 Lead pipe 8 Accumulator 9 Compressor 10 Condenser 11 Pressure reducing device 12 Evaporator 13 Blower 14 Defrost heater

Claims (8)

A refrigerant tube formed in a meandering manner at a predetermined pitch so that a plurality of rows and steps are continuously formed in a straight pipe part and a curved pipe part, and a circular arc part provided on both sides of the rectangular part and the rectangular part A plurality of long holes are provided on the center surface of the plate, and at least a DB plate fin independent for each of the two rows of the refrigerant tubes, and a semi-long hole formed of a rectangular portion and a circular arc portion provided on one short side of the rectangular portion. A plurality of FB plate fins provided on a plate end surface and at least independent for each two rows of the refrigerant tubes, and a plurality of the DB plate fins and a plurality of the FB plate fins arranged at intervals, And a heat exchanger characterized in that the refrigerant tube penetrates and is fixed to the semi-long hole. 2. The heat exchanger according to claim 1, wherein the FB plate fin is arranged in a straight pipe portion where the DB plate fin of the refrigerant tube is difficult to arrange. The heat exchanger according to claim 1, wherein the straight pipe portion in which the DB plate fin of the refrigerant tube is difficult to place is work-hardened. 2. The heat exchanger according to claim 1, wherein a straight pipe portion in which a DB plate fin of the refrigerant tube is difficult to arrange is made smaller than the diameter of the refrigerant tube. The DB plate fins independent for every two rows of refrigerant tubes and the FB plate fins independent for every two rows of refrigerant tubes are arranged in the row direction from the DB plate fins to the refrigerant tubes and from the refrigerant tubes to the FB plate fins. The heat exchanger according to any one of claims 1 to 4. A refrigerant tube formed in a meandering manner at a predetermined pitch so that a plurality of rows and steps are continuously formed in a straight pipe part and a curved pipe part, and a circular arc part provided on both sides of the rectangular part and the rectangular part A plurality of the long holes of the DB plate fins provided on the center surface of the plate, and provided with at least two independent DB plate fins for each of the two rows of the refrigerant tubes. A heat exchanger in which the refrigerant tube is penetrated and fixed, wherein the straight pipe portion of the meandering refrigerant tube in which the DB plate fin is difficult to place is work-hardened. . A refrigerant tube formed in a meandering manner at a predetermined pitch so that a plurality of rows and steps are continuously formed in a straight pipe part and a curved pipe part, and a circular arc part provided on both sides of the rectangular part and the rectangular part A plurality of the long holes of the DB plate fins provided on the center surface of the plate, and provided with at least two independent DB plate fins for each of the two rows of the refrigerant tubes. A heat exchanger in which the refrigerant tube is penetrated and fixed, wherein the straight pipe portion of the meandering refrigerant tube where the DB plate fin is difficult to place is made smaller than the refrigerant tube diameter. Heat exchanger. In the cooling system provided with the compressor, the condenser, the decompression device, the evaporator, and the defrost heater arranged in the lower part of the evaporator, the evaporator is in any 1 paragraph of Claims 1-7. A cooling system comprising the heat exchanger described.

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