JP7522956B2 - Heat exchanger and air conditioner using same - Google Patents

Description

The present invention relates to a fin-tube type heat exchanger and an air conditioner using the same.

In general, air conditioners circulate refrigerant compressed by a compressor through heat exchangers such as condensers and evaporators to exchange heat with the air to provide cooling or heating, but the performance and energy-saving properties of the air conditioner are greatly affected by the heat exchange efficiency of the heat exchanger. Therefore, there is a strong demand for heat exchangers with high efficiency.

The heat exchanger used in this air conditioner is generally a fin-tube type heat exchanger configured by inserting multiple rows of heat transfer tubes into a group of fins, and is installed to cover the front and back sides of the blower (see, for example, Patent Document 1).

Figure 13 shows the air conditioner of Patent Document 1. In this air conditioner, air is drawn in from an inlet 103 of the main body 102 of the conditioner by a once-through blower 101, heat is exchanged in a heat exchanger 104, and the air is then blown out from an outlet 105 to perform air conditioning. The heat exchanger 104 is configured by butting together an upper part of a front heat exchanger 104A bent in an approximately L-shape to surround the blower 101 and a straight rear heat exchanger 104B. The heat exchanger 104 is configured by inserting a heat transfer tube 107 through fins 106 as shown in Figure 14.

When high heat exchange efficiency is required, the heat exchanger 104 used in the air conditioner is arranged in a staggered manner so that the heat transfer tubes 107 in the multiple heat transfer tube rows do not overlap each other in the air flow direction, and in some cases, the pipe diameter of the heat transfer tubes 107 is changed to achieve high efficiency so as to achieve the highest heat exchange performance depending on the state of the refrigerant flowing through the heat transfer tubes 107, i.e., the liquid and gas phase states. For convenience, this type of heat exchanger is referred to as a hybrid type heat exchanger.

The air conditioner using the heat exchanger of the above configuration uses a once-through type blower 101 and has the front heat exchanger 104A bent into an approximately L-shape, so that air sucked toward the center of the once-through type blower 101 flows in and passes through the front heat exchanger 104A in a manner that approximately intersects with each side of the front heat exchanger 104A. However, since the heat transfer tubes 107 in each row are arranged so as not to overlap in the direction of the air flow, the heat exchange rate between each heat transfer tube 107 and the air is high, and since the diameters of the heat transfer tubes 107 are different, high heat exchange performance is achieved according to the gas-liquid state of the refrigerant, and the heat exchanger is highly efficient. This results in good performance and energy saving as an air conditioner.

JP 2004-19999 A

However, the hybrid heat exchanger described in Patent Document 1 is expensive to manufacture, resulting in a significant increase in cost and making the product very expensive.

In other words, when the rows of holes for inserting the heat transfer tubes are press-formed with a drilling die, the hybrid heat exchanger requires a drilling die with hole formation positions offset from each other so that the heat transfer tubes 107 in the multiple heat transfer tube rows do not overlap each other in the air flow direction; for example, a drilling die dedicated to two rows in the case of two rows, and a drilling die dedicated to three rows in the case of three rows.

The diameter of the hole-forming pin shaft of the drilling die also needs to be different in order to change the diameter of the heat transfer tube 107.

In addition, the manufacturing process becomes more complicated, as it is necessary to change to the appropriate drilling die each time a fin with two rows of holes for inserting heat transfer tubes or a fin with three rows of holes for inserting heat transfer tubes is formed.

As a result, the manufacturing costs of heat exchangers increase significantly, making them very expensive.

The present invention was made in consideration of these points, and particularly focused on the problem of increased costs that arise from the need for multiple molds, and aims to provide a highly efficient and inexpensive heat exchanger that can be formed in a simple process using a single mold so that the heat transfer tubes in multiple heat transfer tube rows do not overlap each other in the air flow direction, and an inexpensive, high-performance air conditioner that uses the same.

In order to achieve the above object, the present invention provides a heat exchanger that is constructed by inserting heat transfer tubes into a large number of fin groups, the fins are formed in an approximately L-shape, the angle at the intersection of the extensions of the two straight lines at the windward leading edge of the heat exchanger and the angle at the intersection of the extensions of the two straight lines at the leeward trailing edge form the same obtuse angle, and a curved section of the same shape is formed connecting the two straight lines, and the heat transfer tubes are arranged in at least two rows at a predetermined pitch FP parallel to a line FL that connects the intersection of the extensions of the two straight lines at the windward leading edge and the intersection of the extensions of the two straight lines at the leeward trailing edge, and when the row pitch of each row is SP and the angles between the line FL and the two straight lines at the windward leading edge are α and β, respectively, FP·cosα and FP·cosβ are configured to be within the range of SP·1/4 to SP·3/4.

The air conditioner also has a once-through type blower housed in a main body having an intake port and an exhaust port, and the heat exchanger is disposed in front of the blower.

As a result, this heat exchanger is manufactured by drilling holes for inserting heat transfer tubes while feeding a fin blank plate forward using a drilling die with a row of drilling pins, and then cutting the fin blank plate into a shape with the required row of holes to manufacture the fins.The holes for inserting heat transfer tubes drilled in the straight parts of the fin, i.e., the heat transfer tubes to be inserted into these holes, are shifted sequentially from the windward side to the leeward side without overlapping, resulting in a roughly staggered arrangement.

Therefore, even if the fin has two, three or more rows of heat transfer tubes, a single drilling die with one row of drilling pins is sufficient to drill holes for inserting the heat transfer tubes, and the fin material plate can be simply fed forward without changing the die, allowing the holes to be continuously press-drilled for inserting the heat transfer tubes. The heat transfer tubes are shifted sequentially from the windward side to the leeward side without overlapping, resulting in a roughly staggered arrangement, which increases the degree of air contact with each heat transfer tube, improving heat transfer performance and achieving high heat exchange efficiency.

In other words, it is possible to reduce manufacturing costs while improving heat exchange efficiency, resulting in an inexpensive, highly efficient heat exchanger. And air conditioners using this heat exchanger can also be reduced in cost while improving their performance.

With the above-mentioned configuration, the present invention can use a single mold to arrange the heat transfer tubes so that they do not overlap in the air flow direction, and since mold replacement is not required, the manufacturing process can be simplified, making it possible to provide a highly efficient and inexpensive heat exchanger and an inexpensive, high-performance air conditioner that uses the same.

FIG. 1 is a cross-sectional view showing a heat exchanger according to a first embodiment of the present invention and an indoor unit of an air conditioner using the heat exchanger; FIG. 3 is a plan view showing the fins of the heat exchanger. FIG. 1 is an enlarged plan view showing a main portion of the fin; An explanatory diagram showing an example of manufacturing fins for the heat exchanger FIG. 11 is a plan view showing fins of a heat exchanger according to a second embodiment of the present invention; FIG. 4 is a plan view of the fins showing the state in which the heat exchanger is used in an air conditioner. FIG. 11 is a plan view showing fins of a heat exchanger according to a third embodiment of the present invention; FIG. 1 is a cross-sectional view showing an indoor unit of an air conditioner using the heat exchanger. FIG. 11 is a plan view showing fins of a heat exchanger according to a fourth embodiment of the present invention; FIG. 13 is a cross-sectional view showing a heat exchanger according to a fifth embodiment of the present invention and an indoor unit of an air conditioner using the heat exchanger. FIG. 13 is a cross-sectional view showing a heat exchanger according to a sixth embodiment of the present invention and an indoor unit of an air conditioner using the heat exchanger. FIG. 13 is a cross-sectional view showing a heat exchanger according to a seventh embodiment of the present invention and an indoor unit of an air conditioner using the heat exchanger. FIG. 1 is a cross-sectional view showing a conventional heat exchanger and an indoor unit of an air conditioner using the same. FIG. 3 is a plan view showing the fins of the conventional heat exchanger.

The first invention is a heat exchanger constructed by inserting heat transfer tubes into a number of fin groups, the fins are formed in a roughly dogleg shape, the angle at the intersection of the extensions of the two straight lines at the windward leading edge of the heat exchanger and the angle at the intersection of the extensions of the two straight lines at the leeward trailing edge form the same obtuse angle, and one curved section of the same shape is formed connecting the two straight lines, the heat transfer tubes are arranged in at least two rows at a predetermined pitch FP parallel to a line FL connecting the intersection of the extensions of the two straight lines at the windward leading edge and the intersection of the extensions of the two straight lines at the leeward trailing edge, and the row pitch of each row is SP, and the angles between the line FL and the two straight lines at the windward leading edge are α and β, respectively, so that FP·cosα and FP·cosβ are within the range of SP·1/4 to SP·3/4.

As a result, this heat exchanger is manufactured by drilling holes for inserting the heat transfer tubes while feeding the fin blank plate forward using a drilling die with a row of drilling pins, and then cutting it into a shape with the required row of holes to manufacture the fins.The holes for inserting the heat transfer tubes drilled in the straight parts of the fin, i.e., the heat transfer tubes to be inserted into these holes, are shifted sequentially from the windward side to the leeward side without overlapping, resulting in a roughly staggered arrangement.

Therefore, even if the fin has two, three or more rows of heat transfer tubes, a single drilling die with one row of drilling pins is sufficient to drill holes for inserting the heat transfer tubes, and the fin material plate can be simply fed forward without changing the die, allowing the holes for inserting the heat transfer tubes to be continuously press-drilled. The heat transfer tubes are sequentially shifted from the windward side to the leeward side without overlapping, resulting in a roughly staggered arrangement, which increases the degree of air contact with each heat transfer tube, improving heat transfer performance and achieving high heat exchange efficiency.

In other words, it is possible to reduce manufacturing costs while improving heat exchange efficiency, resulting in an inexpensive, highly efficient heat exchanger.

The second invention is a heat exchanger constructed by inserting heat transfer tubes into a number of fin groups, the fins are formed in a roughly dogleg shape, the angle at the intersection of the extensions of the two straight sections at the leading edge, which is the windward side of the heat exchanger, and the angle at the intersection of the extensions of the two straight sections at the trailing edge, which is the leeward side, form the same obtuse angle, and one curved section of the same shape is formed connecting the two straight lines, the heat transfer tubes are arranged in a row, and the fins with the heat transfer tubes arranged in a row are arranged in a number of rows from the windward side to the leeward side. The heat transfer tubes of each fin are arranged in parallel in at least two rows at a predetermined pitch FP, parallel to a line FL that connects the intersection of the extensions of the two straight lines on the windward leading edge and the intersection of the extensions of the two straight lines on the leeward trailing edge, and when the row pitch of each row is SP and the angles between the line FL and the two straight lines on the windward leading edge are α and β, respectively, FP·cosα and FP·cosβ are configured to be within the range of SP·1/4 to SP·3/4.

As a result, by manufacturing fins with one row of holes through a simple process using a single die, in which a row of holes for inserting heat transfer tubes is press-formed using a single drilling die while the fin material plate is fed forward, and then arranging these, it is possible to ensure that the holes for inserting heat transfer tubes that are arranged in the direction of air flow, in other words, in two or more rows, i.e., the heat transfer tubes, are arranged in a roughly staggered pattern without overlapping each other.

Therefore, as with the first invention, only one drilling die is required to press-form the holes for inserting the heat transfer tubes, and the fin blank plate can be simply fed forward without changing dies, allowing the holes to be continuously press-formed, simplifying the process. This increases the heat exchange rate between the heat transfer tubes and the air, improving heat exchange efficiency while significantly reducing costs, resulting in an inexpensive, highly efficient heat exchanger. In addition, because each fin is independent, insulation is ensured, further improving the performance of the heat exchanger.

The third invention is the first or second invention, in which the heat transfer tubes are configured with a combination of at least two different pitches SP in the row direction.

By positioning the sections with a short pitch SP in the row direction of the heat transfer tubes in the areas where the air flows faster through the heat exchanger, and the sections with a long pitch SP in the areas where the air flows slower, the speed distribution of the air passing through the heat exchanger can be adjusted, improving the heat transfer performance throughout the entire heat exchanger and resulting in a higher performance heat exchanger.

The fourth invention is the first to third inventions, in which the fin has a plurality of first cuts and second cuts on the fin surface that intersect with the first cuts, and the first cuts and second cuts are each configured to open in the direction of air flow.

As a result, when placed on the front side of a once-through type blower, the first cut-out is located in the flow path for air sucked in from the front side of the blower, and the second cut-out is located in the flow path for air sucked in from above, providing resistance to the air flow passing through the heat exchanger, adjusting the speed distribution of the air passing through the heat exchanger and improving the heat exchange efficiency of the heat exchanger.

The fifth invention is the first to fourth inventions, in which the heat transfer tube has two or more different external shapes, large and small.

This allows the heat exchange between the heat transfer tube and the refrigerant to be optimized according to the gas-liquid mixture state of the refrigerant, resulting in a high heat transfer coefficient, making the heat exchanger even more efficient and reducing the material cost of the heat transfer tube, resulting in an even cheaper heat exchanger.

The sixth invention is the first to fifth inventions, in which the angle formed by the intersection of the extensions of the two straight lines on the windward leading edge is the same as the angle formed by the intersection of the extensions of the two straight lines on the leeward trailing edge.

This allows the width dimension of the entire area between the windward leading edge and the leeward trailing edge of the roughly L-shaped fin to be equal, providing a sufficient heat exchange area, and making it possible to produce a highly efficient heat exchanger with high heat exchange efficiency. Furthermore, when cutting the fin blank into the fin shape, no waste material is generated between the leeward edge of the first fin and the windward edge of the second fin, allowing for efficient production.

The seventh invention is the first to sixth inventions, in which the fin has a second fin portion that can be detached from the end of the approximately L-shaped fin.

This allows the heat exchanger formed by the roughly L-shaped fins and the heat exchanger formed by the second fin portion to be manufactured using a single mold by simply cutting off the second fin portion, resulting in significant cost reductions.

The eighth invention is any of the first to seventh inventions, in which the fins are configured by transferring a heat exchange block formed from the separated second fin portion to the front or back of the windward side of the outermost fin.

This allows the heat exchanger's heat transfer area to be secured while reducing the width dimension of the heat exchanger, and when installed in the indoor unit of an air conditioner, the indoor unit's depth size is prevented from increasing, and the remaining fins created by cutting the second fin section can be used to secure the heat transfer area of the heat exchanger, resulting in a high-performance air conditioner with no wasted material.

The ninth invention is a heat exchanger constructed by combining a second heat exchanger of a separate construction with the rear side of the heat exchanger of the first to seventh inventions.

This allows a versatile existing heat exchanger to be combined as the second heat exchanger to provide multiple heat exchangers optimized for cost and application capacity at a lower cost.

The tenth invention is an air conditioner that includes a once-through type blower housed in a body having an intake port and an exhaust port, and a heat exchanger according to any one of the first to ninth inventions is disposed on the front side of the blower.

As a result, the heat exchanger is inexpensive and highly efficient, and the performance of the air conditioner equipped with this heat exchanger can be improved and costs reduced.

The eleventh invention is the tenth invention, in which the suction port is provided on the upper surface of the main body, and the heat exchanger is configured such that the pitch SP in the row direction of the upper heat transfer tubes facing the suction port on the upper surface of the main body is shorter than the pitch SP in the row direction of the heat transfer tubes in other parts.

As a result, the upper part of the fin, where the air flow sucked in from the intake port on the top of the main body is the fastest, has a short pitch SP in the row direction of the heat transfer tube and high resistance, so the flow speed in that part decreases, and the flow speed approaches the flow speed of the air flowing in the part with a long pitch SP, resulting in a uniform flow speed distribution, improving heat transfer performance throughout the entire heat exchanger and making it a high-performance heat exchanger.

The twelfth invention is the tenth to eleventh inventions, in which the suction port is provided on the top surface of the main body, and the heat exchanger has a second raised portion provided on the upper part of the fin that faces the suction port on the top surface of the main body.

As a result, when placed on the front side of a once-through type blower, the first raised part is positioned in the flow path of air passing from the front side of the blower between the rows of heat transfer tubes, providing resistance to the air flow passing through the heat exchanger, and the second raised part is positioned in the flow path of air passing from the upper main body intake port between the rows of heat transfer tubes, providing resistance to the air flow passing through the heat exchanger, effectively adjusting the speed distribution of the air passing through the heat exchanger and further improving the heat exchange efficiency of the heat exchanger.

The following describes an embodiment of the present invention with reference to the drawings. Note that the present invention is not limited to this embodiment.

(Embodiment 1)
The heat exchanger of embodiment 1 of the present invention is incorporated into and used in a separate-type air conditioner consisting of an outdoor unit and an indoor unit connected to each other by refrigerant piping, and its configuration will be described below together with the configuration of the air conditioner.

Figure 1 is a cross-sectional view showing a heat exchanger according to embodiment 1 and an indoor unit of an air conditioner using the same, Figure 2 is a plan view showing the fins of the heat exchanger, Figure 3 is an enlarged plan view showing the main parts of the fins, and Figure 4 is an explanatory diagram showing an example of manufacturing the fins of the heat exchanger.

As shown in FIG. 1, the air conditioner of this embodiment has an intake port 3 on the top surface of the main body 2 of the indoor unit 1, and an outlet port 4 on the bottom surface. Inside the main body 2, a once-through type blower 5 and a fin-tube type heat exchanger 6 are housed.

The heat exchanger 6 is composed of a front heat exchanger 6A arranged on the front side of the main body 2 and a rear heat exchanger 6B arranged on the rear side of the main body 2. The front heat exchanger 6A and the rear heat exchanger 6B are arranged in such a way that they surround the once-through type blower 5 from the upwind side.

The front heat exchanger 6A and rear heat exchanger 6B are arranged in parallel at a predetermined interval and have numerous fins 8, 9 through which air flows, and numerous heat transfer tubes 10 inserted at approximately right angles to the fins 8, 9 and through which the refrigerant flows. The fins 8, 9 of the front heat exchanger 6A and rear heat exchanger 6B are separate, but the heat transfer tubes 10 are connected together, so that they function as a single heat exchanger.

The configuration of the front heat exchanger 6A that is the subject of the present invention is described below.

As shown in Fig. 2, the fins 8 of the front heat exchanger 6A shown in this embodiment are formed in a roughly V-shape. That is, the windward edge and the leeward edge of the fin 8 are each formed in a roughly V-shape consisting of two straight lines 11a, 11b and 12a, 12b whose extensions intersect at the same obtuse angle, and one curved line 13, 14 connecting the straight lines 11a, 11b and 12a, 12b, respectively.

The shapes of the curved portions 13 and 14 may be elliptical, hyperbolic, spline, a shape connected by an approximate straight line, a shape with roughly beveled edges, etc., but in this embodiment, they are arc-shaped as shown in Figure 2. The arc-shaped curved portion 13 of the windward edge and the arc-shaped curved portion 14 of the leeward edge have the same radius of curvature and the same dimensions, and the windward edge consisting of the straight portions 11a and 11b and the leeward edge consisting of the straight portions 12a and 12b are parallel to each other, so that the fin width is the same throughout the entire upper and lower areas.

In addition, each fin 8 has a number of circular holes 15 at predetermined intervals for inserting heat transfer tubes, and the heat transfer tubes 10 are inserted and fixed into these holes 15 as shown in Figure 1.

First, the holes 15 through which the heat transfer tubes 10 are inserted and fixed are arranged in at least two rows at a predetermined pitch FP parallel to a line FL that connects the intersection of the extensions of the two straight lines 11a, 11b at the windward leading edge of the fin 8 and the intersection of the extensions of the two straight lines 12a, 12b at the leeward trailing edge, as shown in Figure 2. Then, when the pitch of each row, i.e., the step pitch in the step direction that is parallel to the outer edge of the approximately dogleg-shaped fin 8, is SP, and the angles between the line FL and the two straight lines at the windward leading edge are α and β, respectively, FP·cosα and FP·cosβ are configured to be within the range of SP·1/4 to SP·3/4.

If the row pitch, which is the width direction length of one row of fins, is RP, then the following relations hold: RP = FP sin α and RP = FP sin β. Therefore, by setting the row pitch RP and the angles α and β, the specified pitch FP can be uniquely determined.

The holes 15 arranged in at least two rows at a predetermined pitch FP parallel to the line FL have the same external shape, but in this embodiment, the external shape of the holes 15 located at the inlet and outlet of the heat exchanger, in this embodiment, the diameter of the circular holes, is at least two different sizes and shapes, large and small, so that the highest heat exchange is achieved between the refrigerant and the heat transfer tube 10 depending on the gas-liquid state of the refrigerant flowing through the heat transfer tube 10. For example, when the air conditioner is in heating operation and the heat exchanger 6 of the indoor unit 1 is used as a condenser or gas cooler, the diameter of the heat transfer tube 10 near the refrigerant outlet is made thinner than any other part. Note that when the air conditioner is in cooling operation, the heat exchanger 6 of the indoor unit 1 is used as an evaporator and the refrigerant in the heat transfer tube 10 flows in the opposite direction, so the area where this thin heat transfer tube 10 is used is the area near the inlet.

As shown in Figures 2 and 3, multiple cut-and-raised portions 16, 17, and 18 (three cut-and-raised portions in this example) are provided on the fin surface between the rows of holes 15 of the fin 8 in the windward direction. The cut-and-raised portions 16, 17, and 18 are arranged approximately parallel to each other, and their raised portions are formed to roughly follow the circumference of the heat transfer tube 10. The width and height of the cut-and-raised portions 16, 17, and 18 are appropriately set in consideration of the heat exchange performance with the air.

Next, we will explain the effects of the air conditioner configured as above.

In the above heat exchanger, the holes 15 in each row through which the heat transfer tubes 10 are inserted and fixed are arranged at a predetermined pitch FP parallel to the line FL connecting the intersection of the extensions of the two straight lines 11a, 11b at the windward leading edge and the intersection of the extensions of the two straight lines 12a, 12b at the leeward trailing edge, as shown in Figures 2 and 3. As a result, as shown in Figure 4, the fin blank plate 19 is fed forward in the direction of the arrow X at the pitch FP, and holes 15 for inserting the heat transfer tubes are drilled using a drilling die (not shown) with a row of drilling pins, and then cut into a shape with the required row of holes, for example, three rows of holes in this case, to manufacture the fins 8.

The holes 15 in each of the three rows of the fins 8 drilled with the one row of drilling dies are arranged so that FP·cosα and FP·cosβ are within the range of SP·1/4 to SP·3/4, when the pitch in the row direction is SP and the angles between the line FL and the two straight lines 11a and 11b at the windward leading edge are α and β, respectively. Therefore, they are arranged in a roughly staggered manner, shifted sequentially from the windward side to the leeward side without overlapping with respect to the flow direction of the air flowing toward the center of the cross-flow type blower 5 (see arrow Y in Figures 2 and 3).

For example, if FP·cosα and FP·cosβ are set to SP·1/2, the heat transfer tubes will be staggered so that the distance between adjacent tubes in the row direction is equal.

Therefore, even if the fin 8 has two or three rows of heat transfer tubes, a single drilling die with one row of drilling pins is sufficient to drill the holes 15 for inserting the heat transfer tubes, and the fin blank plate 19 can be simply fed forward without needing to change dies or the like, allowing the holes 15 for inserting the heat transfer tubes to be continuously press-drilled. This allows the manufacturing costs to be reduced.

Even if the holes are drilled using a single row of drilling dies, the holes 15 in each row of the fins 8 are sequentially shifted in the air flow direction to form a roughly staggered arrangement, so that the heat transfer tubes 10 inserted into the holes 15 have a higher degree of contact with the air, improving heat transfer performance and resulting in high heat exchange efficiency. In other words, even if the holes 15 for inserting the heat transfer tubes are drilled using a single row of drilling dies, the holes 15 can be roughly staggered from the windward side to the leeward side, resulting in a highly efficient heat exchanger.

In this way, the heat exchanger of this embodiment can be manufactured using a single row of drilling dies without the need for die replacement, thereby reducing manufacturing costs and improving heat exchange efficiency, resulting in an inexpensive, highly efficient heat exchanger.

In addition, in this embodiment, the heat transfer tube 10 has an outer shape, and in this example, the tube diameter is made large and small, so that the heat exchange between the heat transfer tube 10 and the refrigerant can be optimized according to the gas-liquid state of the refrigerant, and a high heat transfer rate can be achieved. For example, by making the tube diameter (diameter) of the heat transfer tube 10 closer to the refrigerant outlet when the heat exchanger is used as a condenser or gas cooler, or the heat transfer tube 10 closer to the inlet when used as an evaporator, narrower than any other location, the heat transfer rate of the refrigerant in the heat transfer tube 10 can be improved and the heat exchange capacity can be increased. In addition, since the refrigerant in this region has a high density in the liquid phase, the refrigerant flow resistance does not increase much, and the increase in heat exchange capacity is not hindered.

In this way, the efficiency of the heat exchanger can be further improved, and the reduced diameter of the tube reduces the amount of expensive copper used for the heat transfer tube 10, making it an inexpensive heat exchanger.

In addition, the fin 8 through which the heat transfer tube 10 is inserted has the same angle between the intersection of the extensions of the two straight sections 11a, 11b at the windward leading edge and the intersection of the extensions of the two straight sections 12a, 12b at the leeward trailing edge, so the width of the entire area between the windward leading edge and the leeward trailing edge of the roughly L-shaped fin can be made equal.

As a result, it is possible to provide a sufficient heat exchange area over the entire area of the approximately L-shaped fins, which allows for a high heat exchanger with a large heat exchange capacity and high heat exchange efficiency. In addition, when cutting the fin material plate 19 into the fin shape, no waste material is generated between the cutting of the downwind edge of the first fin and the upwind edge of the second fin, allowing for efficient production.

(Embodiment 2)
FIG. 5 is a plan view showing fins of a heat exchanger according to the second embodiment, and FIG. 6 is a plan view of the fins showing a state in which the heat exchanger is used in an air conditioner.

The heat exchanger of this embodiment is configured with at least two or more types of pitch SP in the row direction of the holes 15 (heat transfer tubes 10) for inserting the heat transfer tubes. In this example, the pitch SP1 of the holes 15a (heat transfer tubes 10) for inserting the heat transfer tubes in the upper row direction facing the intake port 3 on the top surface of the air conditioner body is shorter than the pitch SP2 of the holes 15b (heat transfer tubes 10) for inserting the heat transfer tubes in other parts.

As a result, the upper part of the fin, where the flow of air sucked in from the intake port 3 on the top of the main body is the fastest, has a short pitch SP1 in the row direction of the heat transfer tubes 10 and high resistance, so the flow speed in that part is slower, and the flow speed approaches the flow speed of the air flowing in the part with a long pitch SP2, resulting in a more uniform flow speed distribution, improving the heat transfer performance of the front heat exchanger 6A and making it a high-performance heat exchanger.

In other words, by positioning the heat transfer tubes with a short pitch SP1 in the areas where the air flow speed passing through the front heat exchanger 6A is fast, and the heat transfer tubes with a long pitch SP2 in the areas where the air flow speed is slow, the speed distribution of the air passing through the front heat exchanger 6A can be adjusted, improving the heat transfer performance throughout the entire heat exchanger and resulting in a higher performance heat exchanger.

In particular, when the air conditioner has a single intake port 3 on the top surface of the main body 2 as in this embodiment, the resistance at the top of the fins increases, so the amount of air that flows around from the intake port 3 to the leading edge of the fin increases, and the flow rate distribution is adjusted, making the flow rate distribution more uniform and resulting in a higher performance heat exchanger.

The rest of the configuration and effects are the same as in embodiment 1, so a detailed explanation is omitted.

(Embodiment 3)
FIG. 7 is a plan view showing fins of a heat exchanger according to the third embodiment, and FIG. 8 is a cross-sectional view showing an indoor unit of an air conditioner using the same heat exchanger.

In the heat exchanger of this embodiment, the multiple cut-ups 16, 17, and 18 shown in embodiment 1 are formed to open in the air flow direction as shown in FIG. 7, as shown in FIG. 3 of embodiment 1. For example, the cut-ups are provided on the long side of the fin 8 so as to open toward the windward leading edge (hereinafter, these cut-ups are referred to as first cut-up fins 16a, 17a, and 18a), and on the short side that forms the upper end of the fin 8, they are provided at an angle of approximately 90 degrees that approximately intersects with the first cut-ups 16a, 17a, and 18a (hereinafter, these cut-ups are referred to as second cut-ups 16b, 17b, and 18b).

The first cuts 16a, 17a, 18a are formed in the same shape at a pitch FP in the row direction parallel to a line FL that connects the intersection of the extensions of the two straight lines 11a, 11b on the windward leading edge and the intersection of the extensions of the two straight lines 12a, 12b on the leeward trailing edge.

As a result, when the front heat exchanger 6A is placed on the front side of the once-through type blower 5, the first cut-and-raised portions 16a, 17a, and 18a are positioned in the flow path of the air passing between the rows of heat transfer tubes 10 from the front side of the blower, providing resistance to the air flow passing through the front heat exchanger 6A, and the second cut-and-raised portions 16b, 17b, and 18b are positioned in the flow path of the fast-flowing air passing between the rows of heat transfer tubes 10 from the intake port 3 at the top of the main body, providing resistance to the air flow passing through the front heat exchanger 6A, effectively adjusting the speed distribution of the air passing through the front heat exchanger 6A and further improving the heat exchange efficiency of the heat exchanger.

As explained in the second embodiment, the resistance at the top of the fin increases, and the amount of air that flows around the leading edge of the fin increases, improving the adjustment of the flow velocity distribution, making the flow velocity distribution more uniform and resulting in a higher performance heat exchanger.

The rest of the configuration and effects are the same as in embodiment 1, so a detailed explanation is omitted.

(Embodiment 4)
FIG. 9 is a plan view showing fins of a heat exchanger according to the fourth embodiment.

The heat exchanger of this embodiment is configured such that fins 9 are integrally formed at the ends of fins 8 that are roughly V-shaped and can be separated, as shown in FIG. 2 of embodiments 1 to 3.

This allows the front heat exchanger 6A, which is formed by the roughly L-shaped fins 8, and the rear heat exchanger 6B, which is formed by the fins 9, to be manufactured by pressing the fins 8, 9 in one go using a single die, further reducing costs.

Further, the fin 9 has a second fin portion 20 integrally formed at an end of the fin 9 in a detachable manner.
This allows the fins 8, 9, and 20 of the front side heat exchanger 6A formed by the approximately L-shaped fins 8, the rear side heat exchanger 6B formed by the fins 9, and the heat exchanger block 21 formed by the second fin section 20 to be manufactured all at once by pressing using a single mold, further reducing costs.

The rest of the configuration and effects are the same as in embodiment 1, so a detailed explanation is omitted.

(Embodiment 5)
FIG. 10 is a cross-sectional view showing a heat exchanger according to the fifth embodiment and an indoor unit of an air conditioner using the heat exchanger.

The heat exchanger of this embodiment is configured such that the second fin portion (indicated by 20 in FIG. 9) of the fin 9 formed integrally with the approximately L-shaped fin 8 is cut to form a heat exchange block 21 with the cut second fin portion 20, and this heat exchange block 21 is transferred to the front or back of the windward side of the fin 9 located at the outermost position of the rear heat exchanger 6B.

This makes it possible to ensure the heat transfer area of the rear heat exchanger 6B, which is formed by the fins 8 bent into an approximately L-shape and the fins 9 integral with the rear heat exchanger 6B, while reducing the front-to-rear width dimension L of the rear heat exchanger 6B. Therefore, when installed in the indoor unit of an air conditioner, the depth size of the indoor unit is prevented from becoming large, and the heat transfer area of the entire heat exchanger can be ensured by using the second fin portion 20 created by cutting, resulting in a high-performance air conditioner with no wasted material.

The rest of the configuration and effects are the same as in embodiment 1, so a detailed explanation is omitted.

(Embodiment 6)
Sixth embodiment Fig. 11 is a cross-sectional view showing a heat exchanger according to the sixth embodiment and an indoor unit of an air conditioner using the heat exchanger.

The heat exchanger of this embodiment is constructed by combining the front heat exchanger 6A described in embodiment 1 with a second heat exchanger 22 that is a separate component formed using a separate mold on the rear side of the front heat exchanger 6A.

This allows an existing, versatile heat exchanger formed using a separate mold to be combined as the second heat exchanger 22, making it possible to provide multiple heat exchangers optimized for cost and application capacity at a lower cost.

The rest of the configuration and effects are the same as in embodiment 1, so a detailed explanation is omitted.

(Seventh embodiment)
FIG. 12 is a cross-sectional view showing a heat exchanger according to the seventh embodiment and an indoor unit of an air conditioner using the heat exchanger.

In this embodiment, a fin blank plate 19 in which holes 15 for inserting heat transfer tubes are drilled at pitch FP using a drilling die (not shown) with a row of drilling pins as described in embodiment 1 is cut into a shape with a single row of holes to produce a fin with a single row of holes (hereinafter referred to as a single-hole row fin) 80. A heat exchanger is constructed by arranging multiple single-hole row fins 80 side by side from the upwind side to the downwind side (two in this example).

As a result, the holes 15 of the multiple single-hole row fins 80 arranged side by side from the windward side to the leeward side, i.e., the heat transfer tubes 10, are arranged at a predetermined pitch FP parallel to the line FL connecting the intersection of the extensions of the two straight sections 11a, 11b of the windward leading edge and the intersection of the extensions of the two straight sections 12a, 12b of the leeward trailing edge, as in embodiment 1, and when the pitch in the row direction of the heat transfer tubes 10 is SP and the angles between the line FL and the two straight sections 11a, 11b of the windward leading edge are α and β, respectively, the arrangement is such that FP·cosα and FP·cosβ are within the range of SP·1/4 to SP·3/4.

In other words, this heat exchanger has multiple perforated fins 80 arranged side by side from the windward side to the leeward side, and similarly to the first embodiment, the heat transfer tubes 10 are arranged in at least two rows at a predetermined pitch FP parallel to a line FL connecting the intersection of the extensions of the two straight sections 11a, 11b of the windward leading edge and the intersection of the extensions of the two straight sections 12a, 12b of the leeward trailing edge, and when the row pitch of each row is SP and the angles between the line FL and the two straight sections of the windward leading edge are α and β, respectively, the arrangement is such that FP·cosα and FP·cosβ are within the range of SP·1/4 to SP·3/4.

As in the first embodiment, the fin material plate 19 is fed forward at pitch FP while a single punching die is used to press-form rows of holes for inserting the heat transfer tubes. This simple manufacturing process uses a single metal fitting, and the holes 15 for inserting the heat transfer tubes, that is, the heat transfer tubes 10, arranged in the air flow direction, in other words, in two or more rows, can be arranged in a roughly staggered arrangement without overlapping each other. Therefore, only one punching die is required to press-form the holes 15 for inserting the heat transfer tubes, and the fin material plate 19 can be simply fed forward without changing the die, and the process is simplified. This increases the heat exchange rate between the heat transfer tubes 10 and the air, improving heat exchange efficiency while significantly reducing costs, resulting in an inexpensive and highly efficient heat exchanger.

In addition, since each single-hole fin 80 is independent, insulation is provided between the single-hole fins 80, effectively improving the performance of the heat exchanger.

The heat exchanger and air conditioner according to the present invention have been described above using the above-mentioned embodiments, but the present invention is not limited to these and includes all modifications within the meaning and scope of the claims.

For example, in the heat exchanger of the first to sixth embodiments, the fins 8 are formed with three rows of holes, but the holes 15 may be formed with two rows or multiple rows of three or more rows.

The pitch SP of the heat transfer tubes 10 described in the second embodiment is two types, large and small, but it may be large, medium, small, etc. depending on the flow velocity distribution of the air flowing into the front heat exchanger 6A. Also, the arrangement part with the short pitch SP1 is on the top of the fins 8, but if the intake port 3 of the main body 2 is also provided on the front side, it may be provided in two places, the front side part and the top.

In addition, in the heat exchanger described in this embodiment 7, two perforated fins 80 are arranged side by side, but this can be increased as needed depending on the required capacity of the heat exchanger.

The heat exchanger of this embodiment 7, which is configured with the one-hole row fin 80, may also be configured by combining one or more of the configurations described in the previous embodiments 2 to 6, thereby making it possible to create an even more efficient and inexpensive heat exchanger.

In addition, in this embodiment, the air conditioner is described as a separate type air conditioner in which the indoor unit and the outdoor unit are separate, but this may also be an integrated air conditioner, and the same effect can be obtained.

As explained above, the heat exchanger of the present invention can be made with a single mold to arrange the heat transfer tubes so that they do not overlap in the air flow direction, and since mold replacement is not required, the manufacturing process can be simplified, resulting in a highly efficient and inexpensive heat exchanger. An air conditioner using this heat exchanger can be an inexpensive, high-performance air conditioner. Therefore, it can be widely applied to various air conditioners, including those used in ordinary households.

REFERENCE SIGNS LIST 1 Indoor unit 2 Main body 3 Intake port 4 Outlet port 5 Blower 6 Heat exchanger 6A Front heat exchanger 6B Rear heat exchanger 8, 9 Fin 10 Heat transfer tube 11a, 11b Straight section 12a, 12b Straight section 13, 14 Curved section 15, 15a, 15b Hole 16, 17, 18 Cut-out 16a, 17a, 18a First cut-out 16b, 17b, 18b Second cut-out 19 Fin blank 20 Second fin section 21 Heat exchange block 22 Second heat exchanger 80 Fin with one hole row

Claims (12)

A heat exchanger configured by inserting a heat transfer tube into a fin group consisting of a large number of fins, the fin group having a dogleg-shaped fin portion formed in a generally dogleg-shaped shape, the dogleg-shaped fin portion has an angle at which an extension of two straight lines at a leading edge that is on the windward side of the heat exchanger intersects with an extension of two straight lines at a trailing edge that is on the leeward side, the angle at which an extension of two straight lines at the leading edge intersects with an extension of two straight lines at the trailing edge that is on the leeward side, the two straight lines at the leading edge and the two straight lines at the trailing edge each have a curved portion of the same shape connecting them, and the heat transfer tube that is inserted into the dogleg-shaped fin portion is curved between the two straight lines at the windward leading edge and the dogleg-shaped fin portion. a heat exchanger configured such that the heat transfer tubes are all arranged parallel to a line FL connecting the intersection of the extended line and the intersection of the extended lines of the two straight sections of the leeward trailing edge, the heat transfer tubes passing through the L-shaped fin section are arranged in at least two rows parallel to the line FL at a predetermined pitch FP, the pitch in the row direction of each row is SP and the angles between the line FL and the two straight sections of the windward leading edge are α and β, respectively, FP·cos α and FP·cos β are within the ranges of SP·1/4 to SP·3/4, and the heat transfer tubes do not overlap each other in a direction perpendicular to the straight sections of the leading edge . A heat exchanger constructed by inserting heat transfer tubes into a fin group consisting of a large number of fins, the fin group having an L-shaped fin portion formed in a substantially L-shape, the L-shaped fin portion has an angle at which the extensions of two straight lines at a leading edge that is on the windward side of the heat exchanger intersect with an angle at which the extensions of two straight lines at a trailing edge that is on the leeward side of the heat exchanger intersect at the same obtuse angle, the two straight lines at the leading edge and the two straight lines at the trailing edge are each formed with a curved portion of the same shape connecting them, the heat transfer tubes are arranged in a single row, and a plurality of the L-shaped fin portions with the heat transfer tubes arranged in a single row are arranged in parallel from the windward side to the leeward side, and the parallel arrangement a first angle α and a second angle β of 0.5° to 1.5°, and a second angle β of 0.5° to 1.5°. The heat exchanger of claim 1, wherein the first angle α and the second angle β are parallel to ... A heat exchanger according to claim 1 or 2, in which the heat transfer tubes are configured with a combination of at least two different pitches SP in the row direction. The heat exchanger according to any one of claims 1 to 3, wherein the fin has a plurality of first cuts and second cuts on the surface of the fin that are arranged in a direction intersecting the first cuts, and the first cuts and second cuts are each open in the direction of air flow. A heat exchanger according to any one of claims 1 to 4, in which the heat transfer tubes have two or more different external shapes, large and small. A heat exchanger according to any one of claims 1 to 5, in which the angle formed by the intersection of the extensions of the two straight lines at the windward leading edge is the same as the angle formed by the intersection of the extensions of the two straight lines at the leeward trailing edge. A heat exchanger according to any one of claims 1 to 6, in which the fins are configured with a second fin portion that can be detached from the end of the approximately L-shaped fin. A heat exchanger according to any one of claims 1 to 7, in which the fins are a heat exchange block made up of a separated second fin portion, which is mounted on the front or back of the windward side of the outermost fin. A heat exchanger according to any one of claims 1 to 7, configured by combining a second heat exchanger of a separate construction with the rear side of the heat exchanger. An air conditioner having a once-through type blower housed in a body having an intake port and an exhaust port, and a heat exchanger according to any one of claims 1 to 9 arranged on the front side of the blower. The air conditioner according to claim 10, wherein the suction port is provided on the upper surface of the main body, and the heat exchanger is configured such that the pitch SP in the row direction of the upper heat transfer tubes facing the suction port on the upper surface of the main body is shorter than the pitch SP in the row direction of the heat transfer tubes in other parts. An air conditioner according to any one of claims 10 to 11, in which the intake port is provided on the top surface of the main body, and the heat exchanger is configured with a second raised portion on the upper part of the fin that faces the intake port on the top surface of the main body.