CN1447085A - Heat exchanger - Google Patents

Abstract

The present invention provides a heat exchanger capable of improving manufacturing performance, heat exchange performance and low temperature performance. The heat exchanger is provided with: a plurality of cooling fins (2) arranged side by side at predetermined intervals to allow heat exchange air to flow in the gaps between them; One row is arranged at predetermined intervals in the vertical direction, and several rows are arranged along the flow direction of the heat exchange air to form heat exchange tubes (3) that flow through the flow path of the heat exchange medium inside. The arc-shaped or curved groove portion (5A) between the heat exchange tube rows in the flow direction, the groove portion is provided continuously or separately through at least two cut-off portions (6).

Description

heat exchanger

technical field

The present invention relates to a heat exchanger for an air conditioner, a freezer, a refrigerator, or a showcase (showcase) for exchanging heat between a refrigerant as a heat exchange medium and heat exchange air flowing therethrough.

technical background

Heat exchangers used in air conditioners, freezers, refrigerators, or product display cases are arranged side by side at certain intervals, and there are multiple radiator fins (radiator fins) that allow heat exchange air to circulate through the gaps between them, and are installed through these radiator fins. A heat-exchanging tube (heat-exchanging tube) that circulates a refrigerant (heat exchange medium) between fins and inside.

For a so-called finned-tube type heat exchanger employing such a constitution, various efforts have been made to further improve the heat exchanging performance.

Such as: Patent No. 2706497 once proposed such a heat exchanger, which is characterized in that the plate fins are cut off by the truncation lines of the wavy rows arranged between the heat pipe rows, so that the wavy edges formed by the truncation The bumps mesh with each other.

However, the plate-shaped fins formed by completely separating the heat exchange tube rows have a smaller pitch between the heat exchange tubes in the direction perpendicular to the flow direction of the heat exchange air than other fins. The rigidity of the entire heat sink is reduced.

Therefore, there is a problem that if the plate-shaped heat sink is actually press-worked (press work), the press work cannot be performed well due to a decrease in rigidity, which affects the precision of the finished product.

The present invention focuses on the above-mentioned circumstances, and an object of the present invention is to provide a heat exchanger capable of improving manufacturing performance, heat exchange performance, and low-temperature performance (both heating performance of frosting and defrosting).

In order to achieve the above object, the heat exchanger of the present invention is provided with: a plurality of cooling fins arranged side by side at a certain interval to allow heat exchange air to flow through mutual gaps; One row is arranged at a certain interval in the vertical direction, and several rows are arranged along the flow direction of the heat exchange air, and heat exchange tubes are formed inside to conduct the flow path of the heat exchange medium. The arc-shaped or curved groove between the rows of heat exchange tubes may be continuous through at least two cutouts, or may be provided separately.

In addition, the arc shape or the curved shape constituting the above-mentioned notch portion has a convex portion protruding from the middle line between the tube rows of the heat exchange tubes to the upwind direction of the heat exchange air flow, and the above-mentioned cut-off portion is provided on and arranged in the upwind direction. The downwind part where the heat exchange tubes face.

In addition, the above-mentioned cut-out portions may all be separately provided, and the above-mentioned cut-off portions are provided at predetermined intervals opposite to the heat exchange tubes arranged in the downwind direction of the heat-exchange airflow.

In addition, the above-mentioned heat sink has a cutout portion at its lowermost portion instead of a cutout portion.

In addition, the lowermost part of the above-mentioned fins is notched from the lowermost heat exchange tubes to the lower end surface of the fins in the far side row of heat exchange tubes.

Also, the outer diameter of the heat exchange tubes in the row on the leeward side of the heat exchange airflow is larger than the outer diameter of the heat exchange tubes in the row on the windward side.

Also, if the tube pitch of the above-mentioned heat exchange tubes along the flow direction of the heat exchange air flow is L1, and the tube layer pitch of the above-mentioned heat exchange tubes in the direction perpendicular to the flow direction of the heat exchange air is L2, from the heat exchange The distance from the centerline of the heat exchange tubes on the leeward side of the airflow to the apex of the above-mentioned notch is H, and the distance between the edges of the notch is W, then:

     0.55×L1≤H≤0.95×L1

    0.65×L2≤W≤0.95×L2

By adopting a method for solving such problems, manufacturing performance, heat exchange performance, and heating performance can be improved.

Description of drawings

Fig. 1 is a sectional view showing a heat exchange unit according to a first embodiment of the present invention.

Fig. 2 is a cross-sectional view showing a heat exchanger according to a modified example of the first embodiment.

Fig. 3 is a sectional view showing a heat exchanger according to another modification of the first embodiment.

Fig. 4 is a partial sectional view showing a heat exchanger according to a second embodiment of the present invention and a partial sectional view showing a heat exchanger as a comparative example.

Fig. 5 is a partial sectional view showing a heat exchanger according to a third embodiment of the present invention.

Fig. 6 is a sectional view showing heat exchangers according to a fourth embodiment and a fifth embodiment of the present invention.

Fig. 7 is a partial sectional view showing a heat exchanger according to a sixth embodiment of the present invention.

Fig. 8 is a sectional view showing a heat exchanger according to a seventh embodiment of the present invention.

Fig. 9 is various characteristic graphs demonstrating the results of the embodiment.

In the figure, 2, 2A: cooling fins; 3: heat exchange tubes; 5A-5J are notched parts; 6, 6A: cut-off parts.

Embodiments of the present invention will be described below with reference to the drawings.

Fig. 1 shows the first embodiment. It is a cross-sectional view of a so-called finned-tube type heat exchanger.

The above-mentioned heat exchanger 1A is arranged in parallel at predetermined intervals, and a plurality of plate-shaped cooling fins 2 through which heat-exchanging air flows through mutual gaps are provided through in a direction perpendicular to the direction of the surface of these cooling fins 11, and a refrigerant (thermal heat) flows inside the heat exchanger 1A. Exchange medium) heat exchange tube 3 constitutes.

The heat exchange air flows in the direction of the arrow Z shown in the figure. On the above-mentioned cooling fins 2, a row is arranged at predetermined intervals in the direction perpendicular to the flow direction of the heat exchange air, and multiple rows (here, 2 rows) are arranged along the flow direction of the heat exchange air. ) heat exchange tube 3.

In the above-mentioned heat exchange tube row 3 in the direction perpendicular to the flow direction of the heat exchange air, the distance between the heat exchange tubes 3 is called the tube layer distance P, and the heat exchange tube row arranged along the flow direction of the heat exchange air is called the tube row. Column La, Lb.

The tube row La is the heat exchange tube row 3 provided on the upstream side of the heat exchange air flow, and the tube row Lb is the heat exchange tube row 3 provided on the downstream side of the heat exchange air flow.

The tube layer pitch P of each tube row La, Lb is the same as each other, and the heat exchange tubes 3 on each tube row La, Lb are arranged away from half of the tube layer pitch P, so-called intersecting arrangement.

The fins 2 of this heat exchanger 1A are provided with notches 5A described later. That is, the notched portion 5A is provided between the tube rows La, Lb, and has an arc shape here.

The radius center of the arc shape on the cutout portion 5A is set on the center line of the heat exchange airflow along the heat exchange tubes 3 on the tube row Lb on the leeward side of the heat exchange airflow Z. Therefore, each arc-shaped slot 5A has a curved shape protruding toward the windward side, and surrounds the leeward side heat exchange tube 3 .

The cutouts 5A on the upper end and the lower end of the fin 2 are respectively provided as individual cutouts 5a, and continuous cutouts 5b are provided between these individual cutouts 5a.

Further, a predetermined gap is provided between the lower end of the notch portion 5a provided at the upper end and the upper end of the notch 5b provided at the lower portion. A predetermined gap is provided between the upper end of the notch part 5a provided at the lower end and the lower end of the notch part 5b provided at the upper part.

In the continuous slot portion 5b, the ends of the individual slots 5a are connected to each other by a linear slot c in the same direction as the direction perpendicular to the flow direction of the heat exchange air. Therefore, the continuous notch portion 5b has a nearly wave-like shape.

Since there is no processed portion between the single cut groove portion 5a constituted in this way and the end edge facing the continuous cut groove portion 5b, that is, since it is a portion where the cut groove portions 5a, 5b are cut off, this The place is called the truncation part 6.

The above-mentioned heat exchanger 1A is characterized in that the fins 2 are provided with continuous or individual cutouts 5A through at least two cutouts 6 .

Compared with the above-mentioned blade structure of the heat sink 2 having the notch 5A and the complete separation type, the overall rigidity of the heat sink 2 can be improved, and good heat sink stamping can be performed, thereby improving the manufacturability.

In addition, by disposing the grooved portion 5A and the cut-off portion 6 between the tube rows La and Lb of the heat exchange tube 3, the thermal conductivity of the windward side and the leeward side is reduced, and the fin heat dissipation efficiency (fin efficiency) is improved. The heat exchange performance is improved without changing the fin area.

Fig. 2 is a cross-sectional view of a heat exchanger 1B, a modified example of the first embodiment. Basically, the arrangement structure of the fins 2 and the heat exchange tubes 3 is the same as that described above with reference to FIG. Part 5B and cut-off part 6.

That is, it is characterized in that the notch 5A described above has an arc shape, but the notch portion 5B shown here has a curved shape.

The notched portion 5B is formed by facing the center of the heat exchange tubes 3 of the leeward side tube row Lb, forming a straight line in the direction perpendicular to the flow direction of the heat exchange air, and is processed by equally separating the upper and lower sides. The upper and lower ends of the linear portion are formed by obliquely attaching the heat exchange tubes 3 surrounding the leeward side tube row Lb.

The upper end and the lower end of the heat sink 2 are provided with individual cutouts 5c, and continuous cutouts 5d are formed between these individual cutouts 5c. The continuous groove portion 5d is formed in a nearly concave-convex shape by connecting the mutual end edges of the individual groove portions 5c by the linear groove c in the same direction as the direction perpendicular to the flow direction of the heat exchange air.

In this way, no processing is performed between the facing edges of the single cut groove 5c and the continuous cut groove portion 5d, and it becomes the cutoff portion 6 that cuts off the cutout groove portions 5c, 5d.

The function and effect of the heat exchanger 1B provided with the above-mentioned notch portion 5B and the cut-off portion 6 are exactly the same as those described above, and here, please refer to the above, and no further explanation will be given here.

Fig. 3 is a cross-sectional view of a heat exchanger 1C, which is a further modified example of the first embodiment.

The heat exchanger basically adopts the arrangement of the heat exchange tubes 3 facing the cooling fins 2 described above in FIG. The groove part 5c and the cut-off part 6.

Here, it is characterized in that it is an elongated fin 2A that is particularly long in the vertical direction. That is, since the heat sink 2A is elongated, there are no individual cutouts, but the cutouts 5 c formed continuously are all provided.

Specifically, the upper and lower grooves 5e of the heat sink 2A are respectively continuous in two arc shapes, and five continuous arc grooves 5f and four continuous arc grooves 5g are connected between them. shape.

Between the adjacent continuous arc-shaped notches 5e-5g, there is provided a cut-off portion 6 without any processing. Since a total of four continuous arc-shaped notch portions 5e to 5g are provided, there are a total of three interrupted portions 6 between these.

The functions and effects in the heat exchanger 1C in which the fins 2A are provided with the notched portion 5C and the cut-off portion 6 are exactly the same as those described above, so please refer to the above, and no further explanation will be given here.

Fig. 4(A) is a partial sectional view of a heat exchanger 1D according to a second embodiment of the present invention.

The heat exchanger is basically provided with the arrangement structure of the fins 2 and the heat exchange tubes 3 described above in FIG. and the cut-off part 6.

It is characterized in that, here, all arc-shaped and individual notches 5D are provided. In addition, the arc-shaped apex and its vicinity constituting the notch 5D protrude in the windward direction from the middle line Lc between the tube rows La and Lb of the heat exchange tubes 3 .

In the above-mentioned heat exchanger 1D, the cutout portion 6 formed between both end edges of each cutout portion 5D is provided on the leeward side facing the heat exchange tubes 3 of the upwind side tube row La.

The heat exchanger 1D provided with the cut-out portion 5D and the cut-off portion 6 thus constructed will now be described in comparison with the heat exchanger 1Z provided with the cut-out portion and the cut-off portion 6 as shown in FIG. 4 .

The heat exchanger 1Z shown in FIG. 4(B) is provided with a single notch 5Z that is entirely arc-shaped. Lc is provided protrudingly in the leeward direction, and the blocking portion 6 is provided at the upwind side facing the heat exchange tubes 3 of the leeward tube row Lb.

That is, the grooved portion 5D provided in the heat exchanger 1D of FIG. 4(A) and the grooved portion 5Z provided in the heat exchanger 1Z of FIG. 4(B) protrude in opposite directions, and the heat exchange of the blocking portion 6 is opposite. Tube 3 is positioned differently.

When the heat exchanger 1D described above is used as an outdoor heat exchanger in a refrigerating cycle of an air conditioner, frosting inevitably occurs under low outdoor temperature environmental conditions.

Usually, the amount of frost on the upwind side is more than that on the downwind side, so the hot air discharged from the compressor is set to be directed to the heat exchange tubes 3 of the upwind side tube row La to remove the frost on the upwind side, and then the hot air (hot-gas) Lead to the heat exchange tubes 3 of the leeward side tube row Lb.

Therefore, the temperature of the heat exchange tubes 3 in the leeward side tube row Lb is lower than the temperature of the heat exchange tubes 3 in the upwind side tube row La, and the defrosting effect of the leeward side is lower than that of the upwind side according to the heat exchanger with this simple structure. defrosting effect.

The slot 5Z as a comparative example is provided to surround the heat exchange tubes 3 of the upwind tube row La, so even if the heat of the hot air is transferred from the heat exchange tubes 3 of the upwind tube row La to the leeward side, the slot 5A When the heat supply is cut off, the defrosting effect of the heat exchange tubes 3 and the peripheral portion of the leeward tube row Lb decreases.

Contrary to this, with the configuration of FIG. 4(A), the cutoff portion 6 is formed between the heat exchange tubes 3 of the leeward side tube row Lb, so that hot air can be directly supplied from the upwind side tube row La through the cutoff portion 6. The heat exchange tubes 3 supply heat to the leeward side of the fins 2 well.

Therefore, it can be concluded that with such a heat exchanger 1D, the defrosting effect of the leeward side of the fins 2 is better than that of the comparative example shown in FIG. 4(B).

Fig. 5 is a partial sectional view of a heat exchanger 1E according to a third embodiment of the present invention.

The heat exchanger is provided with the tube row La, which is basically the same as the arrangement of the heat exchange tubes 3 facing the fins 2 described in the first embodiment, and provided in the heat exchange tubes 3 described in the second embodiment. Between Lb are the notched portion 5E and the cut-off portion 6 described later.

All of the above-mentioned notch portions 5E are single and arc-shaped, and the cutout portions 6 are formed between the respective notch portions 5E. Furthermore, the convex part of the notch part 5E protrudes to the windward side from the middle line between the tube rows La and Lb, and the cut-off part 6 is provided on the leeward side facing the heat exchange tubes 3 of the upwind side tube row La.

Therefore, with such a heat exchanger 1E, the effect of improving the defrosting performance obtained in the foregoing second embodiment can be obtained in the heat exchanger 1E as a whole, and the defrosting effect can be further improved.

Fig. 6(A) is a partial cross-sectional view of a heat exchanger 1F according to a fourth embodiment of the present invention.

The heat exchanger is basically provided with the radiator fins 2 and the heat exchanger described in the first embodiment (Fig. 1), the second embodiment (Fig. 4(A)) and the third embodiment (Fig. 5). The arrangement of the heat pipes 3 and the notched portion 5F and the cut portion 6 .

The feature here is that a cutout portion 6A is provided at the lowermost portion of the heat sink 2 instead of the notch portion 5 . That is, the upper end portion of the fin 2 is provided with an arc-shaped single cutout 5a, and the lower side is provided with a continuous cutout 5b via the cutout portion 6 .

The lowermost side of the continuous grooved portion 5b starts from the lower side of the leeward side tube row Lb, and is arranged opposite to the heat exchange tube 3 of the second layer, and is opposite to the heat exchange tube 3 of the lowermost layer, and no grooved portion is provided. It is replaced by a cut-off part 6 .

With such a heat exchanger 1F, the heat conduction between the windward side part and the leeward side part of the fin 2 improves. In particular, the defrosting performance of the lowermost portion of the heat sink 2 where residual frost and residual ice tends to accumulate due to accumulation of defrosted water flowing down from the upper portion during defrosting is improved.

In addition, in the above configuration, the portion facing the lowermost heat exchange tube 3 of the leeward side tube row Lb is the cutout portion 6A, but it is not limited to this, and not only the lowermost layer , it is also possible to expand the range of the cut-off portion 6A to the portion facing the heat exchange tube 3 on the upper layer.

Fig. 6(B) is a partial sectional view of a heat exchanger 1G according to a fifth embodiment of the present invention.

The structure of the heat exchanger is basically the same as that described above in the first embodiment ( FIG. 1 ) to the fourth embodiment ( FIG. 6(A) ), the arrangement of the fins 2 , the heat exchange tubes 3 , and the slotted portion 5G. And the structure of the cutting part 6 is the same.

The feature here is that at the lowermost part of the heat sink 2, instead of the notch 5G, a cut-off portion 6A is provided. In addition, the distance from the bottom heat exchange tube 3 to the lower end surface of the heat sink 2 is the distance from the heat exchange tube 3 on the farthest side row. The lower part is also provided with a notch part 7 .

That is, in the state before the damage, the distance between the heat exchange tubes 3 in the lowermost layer of the leeward side tube row Lb and the lower end edge of the heat sink 2 is longer than the distance between the heat exchange tubes 3 of the upwind side tube row La and the lower end edge of the heat sink 2 . The lower part of the lowermost heat exchange tube 3 on the leeward side tube row Lb of the heat sink 2 is missing.

By making such a heat exchanger 1G, the accumulation of defrosting water flowing down from the upper part during defrosting can be improved, residual frost and residual ice are likely to be generated, and the distance from the heat exchange tube 3 of the cooling fin 2 to the lower end edge of the cooling fin 2 can be increased. side defrosting.

Moreover, the cutout 7 is only provided on the leeward side of the facing heat exchange airflow, but it is not limited thereto. Depending on the arrangement and structure of the heat exchange tubes 3, the same effect can be obtained by forming a notch on the upwind side.

Fig. 7 is a partial sectional view of a heat exchanger 1H according to a sixth embodiment of the present invention. Basically, the fins 2, the arrangement of the heat exchange tubes 3, the cutout portion 5H and the cutout portion 6 described above in the first embodiment (FIG. 1) to the fifth embodiment (6(B)) are provided.

The characteristic here is that the outer diameter of the heat exchange tubes 3A arranged along the leeward side tube row Lb of the heat exchange air flow is larger than the outer diameter of the heat exchange tubes 3 arranged along the windward side tube row La.

That is to say, as mentioned above, during defrosting, the temperature of the heat exchange tubes 3 of the leeward side tube Lb is lower than that of the heat exchange tubes 3 of the upwind side tube row La. The defrosting performance of the peripheral portion of the heat exchange tubes 3 in the row Lb decreases.

Therefore, by setting the outer diameter of the heat exchange tubes 3 of the leeward side tube row Lb to be larger than the outer diameter of the heat exchange tubes 3 of the upwind side tube row La, a large amount of hot air is introduced into the heat exchange tubes 3A of the leeward side tube row Lb, The defrosting performance of these peripheral parts will be improved.

Fig. 8 is a partial sectional view of a heat exchanger 1J according to Embodiment 7 of the present invention.

The heat exchanger is basically provided with the fins 2, the arrangement of the heat exchange tubes 3, the slotted part 5J and the cut-off part 6 described above in the first embodiment (Fig. 1) to the sixth embodiment (Fig. 7).

If the tube row spacing of the heat exchange tubes 3 along the flow direction of the heat exchange air is taken as L1, and the tube layer spacing of the heat exchange tubes 3 in the direction perpendicular to the flow direction of the heat exchange air is L2, the heat exchange of the leeward side tube row Lb The distance from the centerline LL of the tube 3 to the apex of the notch 5 is H, and the distance between the end edges f of the notch 5 is W, which is set as follows:

     0.55×L1≤H≤0.95×L1

    0.65×L2≤W≤0.95×L2

The above numerical values are based on the configuration shown in FIG. 8 , and the distance H from the center line LL of the heat exchange tubes LL of the leeward side tube row Lb to the apex of the slot 5 and the distance W between the edges f of the slot 5 are varied. When heat sinks are tested separately, they are obtained from the results shown in Figure 9(A)(B).

FIG. 9(A) shows changes in low-temperature performance Q when the outer diameter d of heat exchange tubes, the distance between tube rows L1, the distance between tube layers L2, and the distance H to the arc-shaped vertex of the notch 5 are varied. In addition, the so-called low-temperature performance is a heating performance that combines frosting and defrosting.

According to the results in this figure, it can be seen that for the tube distance L1, the low-temperature performance Q is the largest when it is about 0.7 times. On this basis, the larger the distance H, or the smaller the distance H, the lower the low-temperature performance.

Therefore, if about 90% of the distance H is determined as the optimum use limit for the highest value of the low-temperature performance Q, as described above, it can be concluded that the distance to the arc-shaped vertex of the notch 5 The optimal range of H is:

     0.55×L1≤H≤0.95×L1

Moreover, as shown in FIG. 9(B), the outer diameter d of the heat exchange tubes, the distance between tube rows L1, the distance between tube layers L2, and the distance H to the arc-shaped vertex of the notch 5 are fixed, and the edge f of the notch 5 is fixed. Changes in the low-temperature performance Q when the distance between (in the figure, the length of the foot) W varies.

According to the results in this figure, it can be known that for the tube layer distance L2, the low-temperature performance Q is the largest when it is about 0.8 times. will be lower.

Here, if the interval W of about 90% is determined as the optimum range of use for the highest value of the low-temperature performance Q, it can be concluded that, as described above, the interval between the edges f of the notch portion 5 (foot Ministerial length) the optimal range of W is:

    0.65×L2≤W≤0.95×L2

The above-mentioned notches in FIGS. 3 to 8 are arc-shaped, but not limited thereto. Even if they are all changed to curved notches as shown in FIG. 2 , there will be no effect.

As described above, the present invention has the effect of improving the manufacturing performance of the heat sink, and at the same time improving the heat exchange performance and low temperature performance (heating performance of both frosting and defrosting) as a heat exchanger.

Claims (7)

1. A heat exchanger, characterized in that the heat exchanger is provided with: A plurality of cooling fins arranged side by side at predetermined intervals to allow heat exchange air to flow in the mutual gaps; through these cooling fins, a row is arranged at predetermined intervals in the direction perpendicular to the flow direction of heat exchange air. A plurality of rows of heat exchange tubes are arranged along the flow direction of the heat exchange air to form a flow path for the internal flow of the heat exchange medium, The above-mentioned cooling fins are provided with arc-shaped or curved grooves arranged between the heat-exchange tube rows along the flow direction of the heat-exchange air; The notch part is provided continuously or independently through at least two cutout parts. 2. The heat exchanger according to claim 1, wherein the arc-shaped or curved convex portion forming the groove portion is formed from the middle line between the rows of heat-exchanging tubes to the heat-exchanging air flow. The direction of the windward side is prominent; The cutoff portion is provided at a leeward side facing the heat exchange tubes arranged on the windward side. 3 . The heat exchanger according to claim 1 , wherein all of the cutouts are provided independently, and the cutouts are provided facing each other at predetermined intervals between the heat exchange tubes arranged on the leeward side of the heat exchange airflow. 4 . 4. The heat exchanger according to claim 1, wherein the cutout portion is provided at the lowermost portion of the fin instead of the cutout portion. 5 . The heat exchanger according to claim 1 , characterized in that, at the lowermost part of the cooling fins, the lower part of the heat exchange tubes in the row farthest from the lowermost heat exchange tubes to the lower end surface of the cooling fins is missing. 6 . 6. The heat exchanger according to any one of claims 1 to 5, wherein the outer diameter of the heat exchange tubes located on the leeward side of the heat exchange air flow is larger than that of the heat exchange tubes located on the upwind side. outside diameter. 7. The heat exchanger as claimed in claim 3, characterized in that, the row spacing of the above-mentioned heat exchange tubes along the flow direction of the heat exchange air flow is taken as L1, and the above-mentioned heat exchange tubes in the direction perpendicular to the flow direction of the heat exchange air When the tube layer pitch of the heat pipe is L2, the distance from the centerline of the heat exchange tubes on the leeward side of the heat exchange airflow to the apex of the above-mentioned slot is H, and the distance between the edges of the slot is W,     0.55×L1≤H≤0.95×L2     0.65×L2≤W≤0.95×L2

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