OUTDOOR UNIT OF AIR CONDITIONER

Abstract

An outdoor unit of an air conditioner includes: a housing having a box shape, the housing being made of first metal; a heat exchanger disposed in the housing and fixed to the housing via a non-conductive material, at least part of the heat exchanger being made of second metal, the second metal being different in spontaneous potential from the first metal; and a conductive material made of nonmetal, the conductive material being disposed in the housing. The conductive material is fixed to the housing and electrically connected to the housing, and is electrically connected to the heat exchanger.

Description

TECHNICAL FIELD

The present disclosure relates to an outdoor unit of an air conditioner, the outdoor unit including a housing and a heat exchanger.

BACKGROUND

As a conventional outdoor unit of an air conditioner, there is known an outdoor unit including a box-shaped housing and a heat exchanger disposed in the housing, the heat exchanger and the housing being made of dissimilar metals. The types of metal are chosen for the heat exchanger and the housing according to required characteristics. For example, aluminum is generally used for a heat exchanger requiring high thermal conductivity, and iron is generally used for a housing requiring strength.

In a case where moisture adheres to a portion of contact between a heat exchanger and a housing which are dissimilar metals in a state where the heat exchanger and the housing are in direct contact with each other, bimetallic corrosion occurs at a metal having a lower spontaneous potential. Hereinafter, bimetallic corrosion is simply referred to as corrosion. As means for preventing corrosion, indirectly connecting a heat exchanger and a housing via a non-conductive material such as resin is known.

However, when such a means is used, the heat exchanger and the housing are electrically insulated by the non-conductive material. As a result, parasitic capacitance is generated between the heat exchanger and the housing. In addition, such a means has a problem in that a change in voltage is caused in the parasitic capacitance by electromagnetic noise generated by an electronic substrate, a compressor, and the like disposed in the housing, and electromagnetic noise is further generated by the change in voltage. Note that an air inlet for letting in outdoor air is formed in a back surface of the housing, and the heat exchanger is disposed such that the heat exchanger faces the air inlet so as to perform heat exchange with the outdoor air. The electromagnetic noise is emitted from between the heat exchanger and the housing to the outside of the housing through the air inlet.

In order to simultaneously achieve two problem solutions of prevention of corrosion and reduction of electromagnetic noise, Patent Literature 1 discloses a technique in which a conductive connecting material is interposed between a heat exchanger and a housing. The connecting material includes a first connecting portion and a second connecting portion. The first connecting portion is made of the same type of metal as a metal used in the heat exchanger, and is in direct contact with the heat exchanger. The second connecting portion is made of the same type of metal as a metal used in the housing, and is in direct contact with the housing. Furthermore, an insulating layer that electrically insulates the first connecting portion from the second connecting portion is provided between the first connecting portion and the second connecting portion.

In the technique disclosed in Patent Literature 1, part of the insulating layer is removed, and the first connecting portion and the second connecting portion, which are dissimilar metals, are partially brought into direct contact with each other so as to reduce electromagnetic noise by ensuring electrical conduction. Meanwhile, a portion of contact between the first connecting portion and the second connecting portion is covered with a covering material such as waterproof tape so as to block moisture ingress into the contact portion to prevent corrosion of metal.

PATENT LITERATURE

• Patent Literature 1: Japanese Patent No. 6583489

However, in the technique disclosed in Patent Literature 1, the use of multiple types of metal for the connecting material, the provision of the insulating layer, and the use of the waterproof covering material will cause complication of a structure. Thus, the technique disclosed in Patent Literature 1 has problems such as an increase in the number of production steps and an increase in the number of parts.

SUMMARY

The present disclosure has been made in view of the above, and an object of the present disclosure is to obtain an outdoor unit of an air conditioner, capable of achieving both prevention of corrosion and reduction of electromagnetic noise with a simple structure.

To solve the above problems and achieve the object, an outdoor unit of an air conditioner according to the present disclosure includes: a housing, made of first metal, having a box shape; a heat exchanger disposed in the housing and fixed to the housing via a non-conductive material, at least part of the heat exchanger being made of second metal, the second metal being different in spontaneous potential from the first metal; and a conductive material made of nonmetal and disposed in the housing. The conductive material is fixed to the housing and electrically connected to the housing, and is electrically connected to the heat exchanger.

The outdoor unit of an air conditioner, according to the present disclosure has an effect of achieving both prevention of corrosion and reduction of electromagnetic noise with a simple structure.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an exploded perspective view of an outdoor unit of an air conditioner, according to a first embodiment schematically illustrating the outdoor unit.

FIG. 2 is a front view of the outdoor unit of an air conditioner, according to the first embodiment illustrating the outdoor unit in a state where a housing front panel of a housing has been removed.

FIG. 3 is an exploded perspective view of an electronic substrate box and an interface panel in the first embodiment.

FIG. 4 is a perspective view of the electronic substrate box and the interface panel illustrated in FIG. 3 illustrating a state in which the electronic substrate box and the interface panel have been assembled.

FIG. 5 is a right-side view of the outdoor unit of an air conditioner in the first embodiment.

FIG. 6 is a cross-sectional view of the outdoor unit taken along line VI-VI illustrated in FIG. 2.

FIG. 7 is a perspective view of a heat exchanger in the first embodiment schematically illustrating the heat exchanger.

FIG. 8 is a front view of the heat exchanger in the first embodiment.

FIG. 9 is an enlarged view of a main part of the heat exchanger illustrated in FIG. 8.

FIG. 10 is a plan view of a conductive material in the first embodiment illustrating a first conductive material.

FIG. 11 is a plan view of the conductive material in the first embodiment illustrating a second conductive material.

FIG. 12 is a plan view of the outdoor unit of an air conditioner, according to the first embodiment illustrating a state in which a housing top panel of the housing has been removed and the conductive materials have been attached to the housing.

FIG. 13 is a schematic diagram illustrating a transmission path of electromagnetic noise as an electric circuit in the outdoor unit of an air conditioner, according to the first embodiment.

FIG. 14 is a circuit diagram illustrating, as an equivalent circuit, a path through which current serving as electromagnetic noise is transmitted in a case where no conductive material is provided in the outdoor unit of an air conditioner, according to the first embodiment.

FIG. 15 is a rear view of the outdoor unit of an air conditioner, according to the first embodiment illustrating 30 locations where electromagnetic noise is generated in a case where no conductive material is provided.

FIG. 16 is a circuit diagram illustrating, as an equivalent circuit, a path through which current serving as electromagnetic noise is transmitted in a case where the heat exchanger and the housing are brought into direct contact with each other with no insulating material interposed therebetween in the outdoor unit of an air conditioner, according to the first embodiment.

DETAILED DESCRIPTION

Hereinafter, an outdoor unit of an air conditioner, according to an embodiment will be described in detail with reference to the drawings.

First Embodiment

FIG. 1 is an exploded perspective view of an outdoor unit 1 of an air conditioner, according to a first embodiment schematically illustrating the outdoor unit 1. As illustrated in FIG. 1, the outdoor unit 1 of an air conditioner includes a housing 2, a plurality of conductive materials 3, a partition panel 4, a blower 5, a heat exchanger 6, a plurality of insulating materials 7, a compressor 8, and an electronic substrate box 9. Hereinafter, the outdoor unit 1 of an air conditioner may be simply referred to as the outdoor unit 1.

In the following description of a direction of each constituent element of the outdoor unit 1, an X-axis direction is defined as a depth direction of the outdoor unit 1, a Y-axis direction is defined as a height direction of the outdoor unit 1, and a Z-axis direction is defined as a width direction of the outdoor unit 1. In addition, an X-axis positive direction is defined as a forward direction, and an X-axis negative direction is defined as a backward direction. The X-axis positive direction refers to a direction from the negative side to the positive side of the X-axis. The X-axis negative direction refers to a direction from the positive side to the negative side of the X-axis. Furthermore, a Y-axis positive direction is defined as an upward direction, and a Y-axis negative direction is defined as a downward direction. The Y-axis positive direction refers to a direction from the negative side to the positive side of the Y-axis. The Y-axis negative direction refers to a direction from the positive side to the negative side of the Y-axis. In addition, a Z-axis positive direction is defined as a rightward direction, and a Z-axis negative direction is defined as a leftward direction. The Z-axis positive direction refers to a direction from the negative side to the positive side of the Z-axis. The Z-axis negative direction refers to a direction from the positive side to the negative side of the Z-axis. In the first embodiment, the positive side of the X-axis direction to which an airflow generated by the blower 5 in the outdoor unit 1 is externally discharged is considered a front side, and the opposite side of the front side is considered a back side.

FIG. 2 is a front view of the outdoor unit 1 of an air conditioner, according to the first embodiment illustrating the outdoor unit 1 in a state where a housing front panel 2e of the housing 2 has been removed. In FIG. 2, the heat exchanger 6 is shaded by dots for easy understanding. As illustrated in FIGS. 1 and 2, the housing 2 is a box-shaped object serving as an outer shell of the outdoor unit 1. The housing 2 is made of a first metal. The first metal is preferably a metal having high strength. The first metal is, for example, iron or an iron alloy.

As illustrated in FIG. 1, the housing 2 includes a housing floor panel 2a, a housing top panel 2b, a first coupling panel 2c, and a second coupling panel 2d. The housing floor panel 2a forms a bottom of the outer shell of the outdoor unit 1. The shape of the housing floor panel 2a is a rectangle with rounded four corners in plan view. The housing top panel 2b is disposed above the housing floor panel 2a and away from the housing floor panel 2a. The housing top panel 2b forms a ceiling surface of the outer shell of the outdoor unit 1. The shape of the housing top panel 2b is the same as the shape of the housing floor panel 2a in plan view.

The first coupling panel 2c and the second coupling panel 2d couple the housing floor panel 2a to the housing top panel 2b. The first coupling panel 2c has an L shape in plan view. The first coupling panel 2c includes: the housing front panel 2e that extends along the Z-axis direction; and a housing side panel 2f that extends backward from a left edge of the housing front panel 2e. The left edge is one of edges of the housing front panel 2e in the Z-axis direction.

The housing front panel 2e couples a front edge of the housing floor panel 2a to a front edge of the housing top panel 2b. The housing front panel 2e forms a front surface of the outer shell of the outdoor unit 1. An air outlet 2j is formed in the housing front panel 2e. The air outlet 2j is an opening for discharging an airflow generated by the blower 5 to the outside of a fan chamber 10 to be described below. The housing side panel 2f couples a left edge of the housing floor panel 2a to a left edge of the housing top panel 2b. The housing side panel 2f forms a left side surface of the outer shell of the outdoor unit 1. The housing front panel 2e and the housing side panel 2f are integrally formed in the first embodiment, but may be separately formed.

The second coupling panel 2d has an L shape in plan view. The second coupling panel 2d includes: a housing side panel 2g that extends along the X-axis direction; and a housing rear panel 2h that extends leftward from a rear edge of the housing side panel 2g. The rear edge is one of edges of the housing side panel 2g, in the X-axis direction.

The housing side panel 2g couples a right edge of the housing floor panel 2a to a right edge of the housing top panel 2b. The housing side panel 2g forms a right side surface of the outer shell of the outdoor unit 1. The housing rear panel 2h couples part of a rear edge of the housing floor panel 2a to part of a rear edge of the housing top panel 2b. The housing rear panel 2h forms part of a back surface of the outer shell of the outdoor unit 1. The housing side panel 2g and the housing rear panel 2h are integrally formed in the first embodiment, but may be separately formed.

In a state where the panels illustrated in FIG. 1 are assembled, a left edge of the housing rear panel 2h and a rear edge of the housing side panel 2f are separated from each other. An air inlet 2i for letting in outdoor air is formed between the left edge of the housing rear panel 2h and the rear edge of the housing side panel 2f. The air inlet 2i is an opening for letting air in from the outside of the housing 2 and allowing the air to flow into a fan chamber 10 to be described below. The air inlet 2i is surrounded by the housing floor panel 2a, the housing top panel 2b, the housing rear panel 2h, and the housing side panel 2f.

The conductive materials 3 are materials to be disposed in the housing 2. The conductive materials 3 are made of nonmetal having conductivity as opposed to a metal. The material of the conductive materials 3 is, for example, a composite material in which a conductor such as carbon fiber has been kneaded into insulating plastic, or a composite material in which a thin film of a conductor has been formed on the surface of insulating plastic. Examples of such a composite material include carbon graphite. The conductive materials 3 are fixed to the housing 2 and electrically connected to the housing 2, and is electrically connected to the heat exchanger 6. The housing 2 and the heat exchanger 6 are electrically connected via the conductive materials 3. In the present specification, the term “electric connection” between a metal material and each conductive material 3 refers to not only a state in which the metal material and each conductive material 3 are in direct contact with each other and electrically connected to each other, but also a state in which the metal material and each conductive material 3 are electrically connected to each other through a gap. In the first embodiment, the conductive materials 3 are in contact with the housing 2 and the heat exchanger 6.

The housing 2 and each conductive material 3 are joined at a portion of contact between the housing 2 and the conductive material 3, by welding, a screw, or the like. In a case where the surface of each panel of the housing 2 is, for example, coated and the electric resistance of the surface of each panel is high, the electric resistance of the surface of each panel just needs to be lowered by, for example, the partial or complete masking of the joint portion in advance or the peeling off of the coating at the time of screwing each conductive material 3 to the housing 2 by use of a serration screw. The outdoor unit 1 may include a single conductive material 3 or a plurality of conductive materials 3. In the first embodiment, the outdoor unit 1 includes two conductive materials 3, Hereinafter, in a case where the two conductive materials 3 are distinguished from each other, one of the conductive materials 3 is referred to as a first conductive material 3a, and the other conductive material 3 is referred to as a second conductive material 3b.

As illustrated in FIG. 2, the partition panel 4 is a metal material that partitions the inside of the housing 2 into the fan chamber 10 and an electric chamber 11. The partition panel 4 serves as part of the housing 2. The fan chamber 10 and the electric chamber 11 are formed side by side in the Z-axis direction. The partition panel 4 extends in the Y-axis direction from the housing floor panel 2a to the electronic substrate box 9. The partition panel 4 extends in the X-axis direction from the housing front panel 2e to the housing rear panel 2h illustrated in FIG. 1.

The housing 2 and the partition panel 4 illustrated in FIG. 1 are made of the same type of first metal. The housing 2 and the partition panel 4 are joined at a portion of contact between the housing 2 and the partition panel 4, by welding, a screw, or the like. In a case where the surface of each panel of the housing 2 is, for example, coated and the electric resistance of the surface of each panel is high, the electric resistance of the surface of each panel just needs to be lowered by, for example, the partial or complete masking of the joint portion in advance or the peeling off of the coating at the time of screwing the partition panel 4 to the housing 2 by use of a serration screw.

As illustrated in FIG. 2, the blower 5 is a device that is disposed in the fan chamber 10 and generates an airflow. The blower 5 includes: a support 5a that rises from the housing floor panel 2a; a fan motor 5b attached to the support 5a; and a propeller fan 5c attached to a rotation shaft of the fan motor 5b, and rotates as the fan motor 5b rotates. An upper end portion of the support 5a is fixed to the housing top panel 2b. A lower end portion of the support 5a is fixed to the housing floor panel 2a. The fan motor 5b is electrically connected to an electronic substrate 9c to be described below, via a fan drive wire 12. The fan motor 5b rotates when receiving a drive signal output from the electronic substrate 9c via the fan drive wire 12. When the fan motor 5b rotates to drive the propeller fan 5c, a negative pressure is created in the fan chamber 10. As a result, air flows into the fan chamber 10 from the outside of the outdoor unit 1 through the air inlet 2i. The air having flowed into the fan chamber 10 passes through the heat exchanger 6, is changed into an airflow by the blower 5, and is discharged to the outside of the fan chamber 10 from the air outlet 2j illustrated in FIG. 1.

The heat exchanger 6 is an object disposed in the fan chamber 10 and performs heat exchange between a refrigerant and outdoor air. Outdoor air to be taken into the blower 5 passes through the heat exchanger 6. The heat exchanger 6 is, for example, a parallel-flow heat exchanger. The heat exchanger 6 is disposed in the housing 2, and is fixed to the housing 2 via the insulating materials 7 which are non-conductive materials. At least part of the heat exchanger 6 is made of a second metal different in spontaneous potential from the first metal. The second metal is preferably a metal having high thermal conductivity. The second metal is, for example, aluminum or an aluminum alloy. The spontaneous potential of the first metal is higher than the spontaneous potential of the second metal.

As illustrated in FIG. 1, the heat exchanger 6 has an L shape in plan view. The heat exchanger 6 includes: a first heat exchange unit 6a that extends along the Z-axis direction; and a second heat exchange unit 6b that extends along the X-axis direction. The second heat exchange unit 6b extends forward from a left edge of the first heat exchange unit 6a. The left edge is one of edges of the first heat exchange unit 6a in the Z-axis direction. The first heat exchange unit 6a is disposed behind the blower 5. The second heat exchange unit 6b is disposed on the left side of the blower 5 when viewed from the front of the outdoor unit 1. The heat exchanger 6 and the blower 5 are disposed at a distance from each other and electrically insulated, or are disposed via an insulating material (not illustrated) to be electrically insulated.

The heat exchanger 6 is disposed at a distance from the first coupling panel 2c and the second coupling panel 2d and electrically insulated therefrom, or is disposed via an insulating material (not illustrated) to be electrically insulated. As illustrated in FIG. 2, an upper end portion of the heat exchanger 6 is fixed to the housing top panel 2b via the insulating material 7. A lower end portion of the heat exchanger 6 is fixed to the housing floor panel 2a via the insulating material 7. The heat exchanger 6 is electrically insulated from the housing top panel 2b and the housing floor panel 2a. The heat exchanger 6 is disposed such that the heat exchanger 6 does not come into direct contact with metal objects such as the housing 2 and the blower 5 disposed around the heat exchanger 6.

Material having electrical insulation properties, such as resin, is used as the material of the two insulating materials 7 illustrated in FIG. 1. Hereinafter, when the two insulating materials 7 are distinguished from each other, the insulating material 7 provided at the lower end portion of the heat exchanger 6 is referred to as a first insulating material 7a, and the insulating material 7 provided at the upper end portion of the heat exchanger 6 is referred to as a second insulating material 7b. In the first embodiment, the first insulating material 7a and the second insulating material 7b having the same shape and size as those of the heat exchanger 6 in plan view are used for covering the entire bottom and top surface of the heat exchanger 6 so as to electrically insulate the heat exchanger 6 from the housing 2. Meanwhile, this configuration is not intended to limit the means for electrically insulating the two materials. For example, several blocks made of a material having electrical insulation properties may be provided on the bottom of the heat exchanger 6 such that the several blocks are interposed between the heat exchanger 6 and the housing floor panel 2a. With such a configuration, the heat exchanger 6 and the housing floor panel 2a are separated from each other in the Y-axis direction. Thus, the heat exchanger 6 and the housing floor panel 2a can be electrically insulated from each other.

As illustrated in FIG. 2, the compressor 8 is a device that is disposed in the electric chamber 11 and compresses the refrigerant flowing in the heat exchanger 6. The compressor 8 is disposed on the housing floor panel 2a in a lower space in the electric chamber 11. The compressor 8 is fixed to the housing floor panel 2a with a screw or the like.

The electronic substrate box 9 is an object that houses the electronic substrate 9c such as a control board necessary for causing the outdoor unit 1 to operate. The electronic substrate box 9 is formed in a hollow rectangular parallelepiped shape. The electronic substrate box 9 is fixed to an upper end portion of the partition panel 4, and is disposed across the fan chamber 10 and the electric chamber 11. A heat sink 9d extending downward is attached to part of the electronic substrate box 9 disposed in the fan chamber 10. The heat sink 9d is exposed to the fan chamber 10. The heat sink 9d is cooled by an airflow generated by the blower 5.

Part of the electronic substrate box 9 disposed in the electric chamber 11 is disposed above the compressor 8. Compressor drive wires 13 are connected to part of the electronic substrate 9c disposed in the electric chamber 11. The compressor 8 is electrically connected to the electronic substrate 9c via the compressor drive wires 13. The compressor 8 is driven when receiving a drive signal output from the electronic substrate 9c via the compressor drive wires 13.

The electric chamber 11 is surrounded by the housing floor panel 2a, the partition panel 4, the housing side panel 2g, the electronic substrate box 9, and the housing front panel 2e and the housing rear panel 2h illustrated in FIG. 1. The electric chamber 11 has a waterproof structure capable of preventing ingress of moisture such as rainwater from the outside of the housing 2. A stop valve 17 is provided at a lower part of an outer surface of the housing side panel 2g. The stop valve 17 serves as a terminal for connection of refrigerant pipes connected to an indoor unit (not illustrated).

The compressor 8 and the stop valve 17 are connected to each other via a plurality of refrigerant pipes 18. The compressor 8 and the heat exchanger 6 are connected to each other via a plurality of refrigerant pipes 18. Connecting portions 19 for connection between the heat exchanger 6 and the refrigerant pipes 18 are disposed in the electric chamber 11 having the waterproof structure. When the connecting portions 19 are disposed in the electric chamber 11 as described above, contact between the connecting portions 19 and moisture can be prevented. Thus, corrosion of the connecting portions 19 can be prevented. Note that, in order to further enhance the waterproof effect for the connecting portions 19, waterproof tape or the like may be wound around the connecting portions 19 to achieve waterproofing. Although not specifically illustrated, valve devices such as a four-way valve and an expansion valve are connected to the refrigerant pipes 18. The four-way valve switches refrigerant flow directions. The expansion valve expands the refrigerant up to a predetermined pressure. The form of connection of the refrigerant pipes 18 is not limited to that exemplified in the drawing.

An interface panel 20 is installed in an upper space in the electric chamber 11. The interface panel 20 is fixed to an inner surface of the housing side panel 2g and a lower surface of the electronic substrate box 9. A terminal block 21 is installed on the interface panel 20. External AC power lines 14 and internal power lines 15 are connected to the terminal block 21. The external AC power lines 14 are electrically connected to the internal power lines 15 via the terminal block 21. The internal power lines 15 are electrically connected to the electronic substrate 9c. Power is supplied to the electronic substrate 9c via the external AC power lines 14, the terminal block 21, and the internal power lines 15, The voltage of the power to be supplied to the electronic substrate 9c is, for example, a single-phase voltage of 200 V, but is not limited to this voltage.

The interface panel 20 is made of the first metal as with the housing side panel 2g. Therefore, the interface panel 20 is joined to the housing side panel 2g, with low electric resistance. The interface panel 20 is connected to a signal ground of the electronic substrate 9c. The interface panel 20 has a ground connection point 20e to which a ground wire 16 is connected. The interface panel 20 is grounded via the ground connection point 20e and the ground wire 16. The housing 2 joined to the interface panel 20 and the partition panel 4 joined to the housing 2 are grounded via the ground connection point 20e and the ground wire 16.

Next, the configuration of the outdoor unit 1 will be described in more detail. First, configurations of the electronic substrate box 9 and the interface panel 20 will be described with reference to FIGS. 3 and 4. FIG. 3 is an exploded perspective view of the electronic substrate box 9 and the interface panel 20 in the first embodiment. FIG. 4 is a perspective view of the electronic substrate box 9 and the interface panel 20 illustrated in FIG. 3, which illustrates a state in which the electronic substrate box 9 and the interface panel 20 have been assembled.

As illustrated in FIG. 3, the electronic substrate box 9 includes: a lower box 9a being box-shaped and opens upward; a top cover 9b that covers an upper opening of the lower box 9a; and the heat sink 9d. The electronic substrate 9c is disposed in the lower box 9a and fixed to the lower box 9a. The electronic substrate 9c includes: the internal power lines 15 connected to the terminal block 21; and the compressor drive wires 13 connected to the compressor 8. Although not illustrated, the electronic substrate 9c includes various power lines and the like for causing a heater element, the fan motor 5b, and other drive devices to operate.

The heat sink 9d is fixed to the electronic substrate 9c in a state of being in close contact with the electronic substrate 9c. The heat sink 9d plays a role of cooling the heater element of the electronic substrate 9c. The heater element is, for example, a power semiconductor typified by an insulated gate bipolar transistor (IGBT). The electronic substrate 9c to which the heat sink 9d has been fixed is inserted into the lower box 9a from the upper opening of the lower box 9a. As illustrated in FIGS. 3 and 4, the heat sink 9d is partially or completely exposed to the outside of the lower box 9a through a hole 9e formed in a bottom wall of the lower box 9a.

The lower box 9a and the top cover 9b illustrated in FIG. 3 are made of, for example, rubber, resin, metal such as iron, or a combination thereof. For example, in a case where the lower box 9a and the top cover 9b are made of metal, the electronic substrate box 9 has a structure such that the periphery of the electronic substrate 9c is covered with metal. It is thus possible to suppress emission of electromagnetic noise generated by the electronic substrate 9c to the outside of the electronic substrate box 9. There is a possibility that moisture such as rainwater spattered in the fan chamber 10 may enter the electronic substrate box 9 and the electric chamber 11 through the hole 9e formed in the bottom wall of the lower box 9a. Therefore, in practice, measures such as devising better shapes of the hole 9e and the lower box 9a so that moisture does not easily enter or newly adding a structure for waterproofing are taken to ensure the waterproofness of the inside of the electronic substrate box 9 and the electric chamber 11.

The interface panel 20 includes an interface vertical wall 20a, an upper joint flange portion 20b, an interface transverse wall 20c, and a lower joint flange portion 20d. The interface vertical wall 20a is a vertical wall extending along the Y-axis direction. The upper joint flange portion 20b extends horizontally in the Z-axis direction from an upper edge of the interface vertical wall 20a. The upper joint flange portion 20b is joined to the lower surface of the bottom wall of the lower box 9a. The interface transverse wall 20c extends horizontally in the Z-axis direction from a lower edge of the interface vertical wall 20a. The lower joint flange portion 20d extends downward in the Y-axis direction from a front edge of the interface transverse wall 20c. The lower joint flange portion 20d is joined to the inner surface of the housing side panel 2g illustrated in FIG. 2. The lower joint flange portion 20d of the interface panel 20 is fixed to the housing side panel 2g and electrically connected to the housing side panel 2g. The interface panel 20 is fixed to each of the housing side panel 2g and the lower box 9a.

Next, the configuration of a right side surface of the outdoor unit 1 will be described with reference to FIG. 5. FIG. 5 is a right-side view of the outdoor unit 1 of an air conditioner, in the first embodiment.

An opening 2k is formed in the housing side panel 2g. The opening 2k allows the inside and outside of the housing 2 to communicate with each other. An interface cover 22 is detachably attached to the housing side panel 2g. The interface cover 22 opens and covers the opening 2k by detachment and attachment. When attached, the interface cover 22 covers the opening 2k; and when detached, the interface cover 22 opens the opening 2k. The interface panel 20 and the terminal block 21 installed in the electric chamber 11 can be visually recognized and handled through the opening 2k. It is possible to perform the work of connecting various power lines through the opening 2k by detaching the interface cover 22 from the housing side panel 2g.

The interface cover 22 plays a role of preventing ingress of moisture such as rainwater into the electric chamber 11 while ensuring air permeability between the electric chamber 11 and the outside of the housing 2. The interface cover 22 is made of resin, metal such as iron, or a combination thereof. In a case where the interface cover 22 is made of metal such as iron and is joined to the housing side panel 2g, with low electric resistance, it is possible to suppress emission of electromagnetic noise from the opening 2k to the outside of the housing 2 by covering the opening 2k with the interface cover 22.

Although not illustrated, a hole is formed in the interface cover 22 for the purpose of ensuring ventilation between the electric chamber 11 and the outside of the housing 2 and allowing a power line from the outside of the housing 2 to be put into and removed from the electric chamber 11. Waterproof measures are taken for the hole so that moisture such as rainwater does not enter the electric chamber 11. Examples of the waterproof measures include putting sponge in a gap between the power line and the inner surface of the hole or forming the hole with a louver structure.

Next, the configuration of the partition panel 4 will be described with reference to FIG. 6. FIG. 6 is a cross-sectional view of the outdoor unit 1 taken along line VI-VI illustrated in FIG. 2. In FIG. 6, only the housing 2 is hatched for easy understanding.

The partition panel 4 includes a first partition 4a and a second partition 4b continuous with a rear edge of the first partition 4a. An introduction hole 4c for introducing a Z-axis direction end of the heat exchanger 6 into the electric chamber 11 is formed in the second partition 4b. The heat exchanger 6 and the second partition 4b are made of dissimilar metals. For example, a resin material is preferably interposed between the heat exchanger 6 and the second partition 4b so as to avoid contact between dissimilar metals.

Next, the configuration of the heat exchanger 6 will be further described with reference to FIGS. 7 to 9. FIG. 7 is a perspective view of the heat exchanger 6 in the first embodiment schematically illustrating the heat exchanger 6. FIG. 8 is a front view of the heat exchanger 6 in the first embodiment. FIG. 9 is an enlarged view of a main part of the heat exchanger 6 illustrated in FIG. 8.

As illustrated in FIG. 7, the heat exchanger 6 is a parallel-flow heat exchanger in the first embodiment. As illustrated in FIG. 8, the heat exchanger 6 includes two headers 6c and 6d, a plurality of refrigerant conduits 6e, and a plurality of fins 6f.

The two headers 6c and 6d are both hollow metal objects. Each of the headers 6c and 6d extends along the Y-axis direction. As illustrated in FIG. 7, the two headers 6c and 6d are disposed away from each other in the Z-axis direction, and are disposed in such a way as to be shifted from each other in the X-axis direction. The header 6c is provided at a front edge of the second heat exchange unit 6b. The header 6d is provided at a right edge of the first heat exchange unit 6a. The refrigerant pipes 18 are connected to the header 6d.

Each of the refrigerant conduits 6e illustrated in FIG. 8 is a hollow metal object. Each refrigerant conduit 6e is, for example, a flat pipe having a flat shape. The plurality of refrigerant conduits 6e are disposed at a distance from each other in the Y-axis direction. Each of the refrigerant conduits 6e extends from one of the headers 6c to the other header 6d. The direction in which each refrigerant conduit 6e extends is orthogonal to the Y-axis direction. One end of each refrigerant conduit 6e in the extending direction is connected to the one of the headers 6c, and another end of each refrigerant conduit 6e in the extending direction is connected to the other header 6d. Each refrigerant conduit 6e allows the one of the headers 6c to communicate with the other header 6d.

The fins 6f are plate-like objects made of metal. Each fin 6f is disposed between adjacent refrigerant conduits 6e. The shape of each fin 6f is not particularly limited, but is a wave shape alternately protruding upward and downward in the first embodiment. That is, the fins 6f are corrugated fins in the first embodiment. As illustrated in FIG. 9, each fin 6f is in contact with each of the adjacent refrigerant conduits 6e, and is joined thereto by welding or the like.

The refrigerant flows inside the headers 6c and 6d and inside the refrigerant conduits 6e illustrated in FIG. 8. One of the two headers 6c and 6d plays a role of distributing the refrigerant to each of the plurality of refrigerant conduits 6e. The other of the two headers 6c and 6d plays a role of merging the refrigerant flowing out of each of the plurality of refrigerant conduits 6e. The refrigerant conduits 6e play a role of performing heat exchange between the refrigerant and outdoor air, That is, heat exchange is performed between the refrigerant flowing inside the refrigerant conduits 6e and outdoor air flowing around the refrigerant conduits 6e. The fins 6f play a role of promoting heat exchange between the refrigerant and outdoor air.

Next, the configurations of the conductive materials 3 will be further described with reference to FIGS. 10 and 11. FIG. 10 is a plan view of the conductive material 3 in the first embodiment illustrating the first conductive material 3a. FIG. 11 is a plan view of the conductive material 3 in the first embodiment illustrating the second conductive material 3b. FIG. 12 is a plan view of the outdoor unit 1 of an air conditioner, according to the first embodiment illustrating a state in which the housing top panel 2b of the housing 2 has been removed and the conductive materials 3 have been attached to the housing 2. FIG. 12 illustrates the heat exchanger 6 in direct contact with the partition panel 4, the housing side panel 2f, and the like of the housing 2. Actually, however, the heat exchanger 6 is disposed such that the heat exchanger 6 does not come into direct contact with a metal object such as the housing 2. In FIG. 12, the heat exchanger 6 is shaded by dots for easy understanding.

As illustrated in FIG. 10, the shape of the first conductive material 3a is not particularly limited, but is an L shape in the first embodiment. The first conductive material 3a includes a first plate portion 3c and a second plate portion 3d. The first conductive material 3a illustrated in FIG. 12 electrically connects the partition panel 4 and the first heat exchange unit 6a. The first conductive material 3a is disposed in the fan chamber 10. The first conductive material 3a is disposed at an inner corner formed by the partition panel 4 and the first heat exchange unit 6a. The first conductive material 3a is disposed on the left side of the partition panel 4, The first conductive material 3a is disposed in front of the first heat exchange unit 6a. The first conductive material 3a is fixed to the partition panel 4, which is part of the housing 2, and electrically connected to the partition panel 4, and is electrically connected to the first heat exchange unit 6a.

The first plate portion 3c extends along the X-axis direction. The first plate portion 3c is in contact with a side surface 4d of the partition panel 4 facing the fan chamber 10. The side surface 4d is a plane extending in the X-axis direction and the Y-axis direction. The first plate portion 3c is fixed to the partition panel 4. The second plate portion 3d extends along the Z-axis direction. The second plate portion 3d extends leftward from a rear edge of the first plate portion 3c. The rear edge is one of edges of the first plate portion 3c in the Z-axis direction. The second plate portion 3d is in contact with a front surface 6g of the first heat exchange unit 6a facing the fan chamber 10. The front surface 6g is a plane extending in the Z-axis direction and the Y-axis direction.

As illustrated in FIG. 11, the shape of the second conductive material 3b is not particularly limited, but is a crank shape in the first embodiment. The second conductive material 3b includes a fixed portion 3e, a plate portion 3f, and a coupling portion 3g that couples the fixed portion 3e to the plate portion 3f. The second conductive material 3b illustrated in FIG. 12 electrically connects the housing side panel 2f and the second heat exchange unit 6b. The second conductive material 3b is disposed in the fan chamber 10. The second conductive material 3b is disposed at an inner corner formed by the housing side panel 2f and the second heat exchange unit 6b. The second conductive material 3b is disposed on the right side of the housing side panel 2f. The second conductive material 3b is disposed in front of the second heat exchange unit 6b, and extends leftward. The second conductive material 3b is fixed to the housing side panel 2f and electrically connected to the housing side panel 2f, and is electrically connected to the second heat exchange unit 6b.

The fixed portion 3e extends along the X-axis direction. The fixed portion 3e is in contact with an inner surface 2m of the housing side panel 2f facing the fan chamber 10. The inner surface 2m is a plane extending in the X-axis direction and the Y-axis direction. The fixed portion 3e is fixed to the housing side panel 2f. The coupling portion 3g extends rightward from a rear edge of the fixed portion 3e. The rear edge is one of edges of the fixed portion 3e in the X axis direction. The coupling portion 3g extends along the Z-axis direction. The coupling portion 3g is in contact with a front surface 6h of the second heat exchange unit 6b facing the fan chamber 10. The front surface 6h is a plane extending in the z-axis direction and the Y-axis direction. The plate portion 3f extends backward from a right edge of the coupling portion 3g. The right edge is one of edges of the coupling portion 3g in the Z axis direction. The plate portion 3f extends along the X-axis direction. The plate portion 3f is in contact with a side surface 6i of the second heat exchange unit 6b facing the fan chamber 10. The side surface 6i is a plane extending in the X-axis direction and the Y-axis direction. The side surface 6i extends backward from a right edge of the front surface 6h to the front surface 6g. The right edge is one of edges of the front surface 6h in the Z-axis direction.

In the first embodiment, the conductive materials 3 are fixed to the housing side panel 2f or the partition panel 4 to be electrically connected to the housing 2. However, the conductive materials 3 just need to be fixed to at least one of the housing floor panel 2a, the housing top panel 2b, the housing front panel 2e, the housing rear panel 2h, the housing side panels 2f and 2g, and the partition panel 4 to be electrically connected to the housing 2. The size of each conductive material 3 is preferably set in such a way as to allow electrical connection between the housing 2 and the heat exchanger 6 to be maintained without being affected even by vibration or the like while the outdoor unit 1 is operating.

Next, operation and effects of the outdoor unit 1 according to the first embodiment will be described.

As illustrated in FIG. 2, when power is supplied from the external AC power lines 14 to the electronic substrate 9c via the internal power lines 15, the electronic substrate 9c enters a standby state. When receiving an operation start command signal from the indoor unit (not illustrated) via a communication signal line between the indoor unit and the outdoor unit 1, the electronic substrate 9c causes the outdoor unit 1 to start operating. Specifically, the electronic substrate 9c outputs a drive signal to the fan motor 5b through the fan drive wire 12 to drive the fan motor 5b. Furthermore, the electronic substrate 9c outputs another drive signal to the compressor 8 through the compressor drive wires 13 to drive the compressor 8. At this time, rectangular-wave pulses generated by the switching of a power semiconductor are generally used as the drive signals to be output from the electronic substrate 9c. Therefore, the drive signals include high-frequency components that are not originally necessary for driving alternating-current motors of the compressor 8 and the fan motor 5b, such as switching noise of the power semiconductor and harmonic components of the rectangular-wave pulses. Such high-frequency components become: electromagnetic noise sources; and a cause the electromagnetic noise to be emitted to the outside of the housing 2 through a transmission path to be described below.

FIG. 13 is a schematic diagram illustrating the transmission path of electromagnetic noise as an electric circuit in the outdoor unit 1 of an air conditioner, according to the first embodiment. In FIG. 13, the heat exchanger 6 is shaded by dots for easy understanding. For example, when a three-phase motor is used as the alternating-current motor of the compressor 8, electromagnetic noise generated in the electronic substrate 9c is transmitted to a housing of the compressor 8 via a three-phase motor winding neutral point 8d through a parasitic capacitance 8b existing between a motor winding 8a and the housing of the compressor 8. Part of the electromagnetic noise transmitted to the housing of the compressor 8 is transmitted to the housing floor panel 2a and then returned to the electronic substrate 9c. However, since there are impedance components such as a contact resistance 8c between the housing of the compressor 8 and the housing floor panel 2a, part of the electromagnetic noise transmitted to the housing of the compressor 8 is transmitted to the heat exchanger 6 through the refrigerant pipes 18.

Characteristics of parasitic impedance components of the heat exchanger 6 vary depending on the structure of the heat exchanger 6. Here, assuming that the heat exchanger 6 is a parallel-flow heat exchanger including the fins 6f and the refrigerant conduits 6e having a flat shape, as illustrated in FIG. 8, an equivalent circuit in which parasitic inductances 23 included in the heat exchanger 6 are combined as illustrated in FIG. 13 is shown as an example. The parasitic impedance components such as the parasitic inductances 23 included in the heat exchanger 6 are complicatedly present as a distributed constant circuit as illustrated in FIG. 13. Since the heat exchanger 6 and the housing 2 are electrically insulated by the first insulating material 7a and the second insulating material 7b, parasitic capacitances 22a and 22b are generated between the heat exchanger 6 and the housing 2. That is, the parasitic capacitance 22a is generated between the heat exchanger 6 and the housing floor panel 2a, and the parasitic capacitance 22b is generated between the heat exchanger 6 and the housing top panel 2b. The parasitic capacitances 22a and 22b are generated on the transmission path of electromagnetic noise.

FIG. 14 is a circuit diagram illustrating, as an equivalent circuit, a path through which current serving as electromagnetic noise is transmitted in a case where no conductive material 3 is provided in the outdoor unit 1 of an air conditioner, according to the first embodiment. Electromagnetic noise transmitted from the electronic substrate 9c to the heat exchanger 6 and the housing 2 illustrated in FIG. 13 through the compressor 8 generates: resonance with the parasitic inductances 23 included in the heat exchanger 6; resonance with the parasitic capacitances 22a and 22b; and resonance with a parasitic impedance component such as a parasitic inductance 24 of each panel of the housing 2. At this time, a change in voltage occurs in the parasitic capacitances 22a and 22b due to resonance.

FIG. 15 is a rear view of the outdoor unit 1 of an air conditioner, according to the first embodiment illustrating locations where electromagnetic noise is generated in a case where no conductive material 3 is provided. In FIG. 15, the heat exchanger 6 is shaded by dots for easy understanding. Gaps G1, G2, G3, and G4 are formed between the heat exchanger 6 and the panels of the housing 2 so as to ensure electrical insulation. In FIG. 15, locations of the gaps G1, G2, G3, and G4 are surrounded by broken lines. FIG. 15 illustrates as if the gaps G1, G2, G3, and G4 do not exist in part of a space between the heat exchanger 6 and the housing 2, but actually, the gaps G1, G2, G3, and G4 exist, which are elongated and extend in such a way as to surround four sides of the heat exchanger 6. The gaps G1, G2, G3, and G4 correspond to locations where electromagnetic noise is generated when the outdoor unit 1 includes no conductive material 3. Voltage changes occur between the heat exchanger 6 and the housing floor panel 2a and between the heat exchanger 6 and the housing top panel 2b through the parasitic capacitances 22a and 22b illustrated in FIG. 13, respectively. As a result, the gaps G1, G2, G3, and G4 function as slot antennas, and further generate electromagnetic noise according to changes in voltages applied to both ends of the gaps G1, G2, G3, and G4. The electromagnetic noise generated in the gaps G1, G2, G3, and G4 is emitted to the outside of the housing 2 through the air inlet 2i when the outdoor unit 1 includes no conductive material 3.

FIG. 16 is a circuit diagram illustrating, as an equivalent circuit, a path through which current serving as electromagnetic noise is transmitted in a case where the heat exchanger 6 and the housing 2 are brought into direct contact with each other with no insulating material 7 interposed therebetween in the outdoor unit 1 of an air conditioner, according to the first embodiment. As a result of removal of the first insulating material 7a and the second insulating material 7b illustrated in FIG. 15, the heat exchanger 6 and each panel of the housing 2 are electrically connected. That is, the heat exchanger 6 and each panel of the housing 2 are electrically short-circuited. Therefore, as illustrated in FIG. 16, the parasitic capacitances 22a and 22b generated between the heat exchanger 6 and the panels of the housing 2 are short-circuited. As a result, no voltage change occurs between the heat exchanger 6 and the housing floor panel 2a and between the heat exchanger 6 and the housing top panel 2b illustrated in FIG. 15 through the parasitic capacitances 22a and 22b illustrated in FIG. 16, respectively, and no electromagnetic noise is generated in the gaps G1, G2, G3, and G4.

In a case where the heat exchanger 6 and the housing 2 illustrated in FIG. 15 are made of dissimilar metals and no insulating material 7 is provided between the heat exchanger 6 and the housing 2, generation of electromagnetic noise in the gaps G1, G2, G3, and G4 can be prevented to reduce emission of electromagnetic noise to the outside of the housing 2, but corrosion occurs in the heat exchanger 6 having a low spontaneous potential at a portion of contact between the heat exchanger 6 and the housing 2. Meanwhile, when the insulating materials 7 are provided between the heat exchanger 6 and the housing 2, it is possible to prevent corrosion of the heat exchanger 6 having a low spontaneous potential at the portion of contact between the heat exchanger 6 and the housing, however, electromagnetic noise is generated in the gaps G1, G2, G3, and G4, so that an amount of electromagnetic noise to be emitted to the outside of the housing 2 increases.

As illustrated in FIG. 12, the outdoor unit 1 of the first embodiment includes: the housing 2 having a box shape and made of the first metal; the heat exchanger 6 made of the second metal having a spontaneous potential different from that of the first metal, disposed in the housing 2, and fixed to the housing 2 via the insulating materials 7; and the conductive materials 3 made of nonmetal and disposed in the housing 2. The conductive materials 3 are fixed to the housing 2 and electrically connected to the housing 2, and is electrically connected to the heat exchanger 6. With these configurations, the heat exchanger 6 and the housing 2 are electrically connected via the conductive materials 3. Therefore, the parasitic capacitances 22a and 22b generated between the heat exchanger 6 and the panels of the housing 2 illustrated in FIG. 13 are short-circuited. As a result, voltage changes to be generated through the parasitic capacitances 22a and 22b between the heat exchanger 6 and the housing 2 are suppressed, so that electromagnetic noise to be emitted from the gaps G1, G2, G3, and G4 illustrated in FIG. 15 is suppressed.

In the first embodiment, the heat exchanger 6 and housing 2 are not in direct contact with each other, as illustrated in FIG. 12. As a result, it is possible to prevent corrosion from occurring due to contact between the heat exchanger 6 and housing 2. Furthermore, in the first embodiment, since the conductive materials 3 are made of nonmetal, it is possible to prevent corrosion from occurring due to contact between the housing 2 and the conductive materials 3 and prevent corrosion from occurring due to contact between the heat exchanger 6 and the conductive materials 3. That is, it is possible to achieve both prevention of corrosion and reduction of electromagnetic noise with a simple structure in which the outdoor unit 1 includes the conductive materials 3.

In the first embodiment, the conductive materials 3 are fixed to and electrically connected to the housing side panel 2f and the partition panel 4, as illustrated in FIG. 12. Meanwhile, the conductive materials 3 may be fixed to all the housing floor panel 2a, the housing top panel 2b, the housing front panel 2e, the housing rear panel 2h, the housing side panels 2f and 2g, and the partition panel 4 illustrated in FIG. 1. In a case where the conductive materials 3 are thus configured, electrical connection between the panels is strengthened. As a result, the contact resistance and the parasitic inductances 23 of the housing 2 illustrated in FIG. 13 can be reduced. Therefore, it is possible to reduce electromagnetic noise to be transmitted to the electronic substrate 9c, the compressor 8, and each panel of the housing 2. That is, it is possible to reduce noise terminal voltage, disturbance power intensity, and the like.

In the first embodiment, the spontaneous potential of the first metal is higher than the spontaneous potential of the second metal. Therefore, when the heat exchanger 6 and housing 2 are brought into direct contact with each other, corrosion occurs in the heat exchanger 6 made of the second metal. In this regard, the heat exchanger 6 and the housing 2 are not in direct contact with each other in the first embodiment, as described above. Therefore, corrosion of the heat exchanger 6 can be prevented.

In the first embodiment, since the first metal is iron or an iron alloy, the strength of the housing 2 made of the first metal can be increased. Furthermore, in the first embodiment, since the second metal is aluminum or an aluminum alloy, thermal conductivity of the heat exchanger 6 made of the second metal can be enhanced.

Conventional heat exchangers include a serpentine heat exchanger and a parallel-flow heat exchanger made of aluminum. Each of the serpentine heat exchanger and the parallel-flow heat exchanger includes a fin and a refrigerant conduit. In the serpentine heat exchanger, aluminum is generally used as a material of a fin and copper is generally used as a material of a refrigerant conduit. When iron is used as the material of the housing 2, the magnitude relationship between the respective standard electrode potentials of the metals is as follows: aluminum<iron<copper. That is, the magnitude relationship between the respective standard electrode potentials of the metal materials is as follows: fin<housing 2<refrigerant conduit. If the fin and the refrigerant conduit of the serpentine heat exchanger are brought into direct contact with the housing 2 and moisture adheres to a portion of contact between the fin and the housing 2 and a portion of contact between the refrigerant conduit and the housing 2, corrosion may occur in the fin having a standard electrode potential lower than that of the housing 2, but corrosion does not occur in the refrigerant conduit having a standard electrode potential higher than that of the housing 2.

Meanwhile, aluminum is used as the material of the fin and the refrigerant conduit in the parallel-flow heat exchanger made of aluminum. Therefore, when iron is used as the material of the housing 2, corrosion may occur in both the fin and the refrigerant conduit. When corrosion occurs in the refrigerant conduit to form a hole, a refrigerant in the refrigerant conduit leaks into the atmosphere. Leakage of the refrigerant into the atmosphere impairs a cooling and heating function of an air conditioner. As described above, the adverse effect of corrosion is large in the parallel-flow heat exchanger made of aluminum, Thus, it is highly important to take measures to prevent corrosion, and it is also necessary to take measures to reduce electromagnetic noise to be generated due to the measures taken to prevent corrosion. Therefore, it is particularly useful to achieve both prevention of corrosion and reduction of electromagnetic noise by using the nonmetallic conductive materials 3 illustrated in FIG. 12, as in the first embodiment, in the case of using a heat exchanger with a large adverse effect of corrosion, such as the parallel-flow heat exchanger made of aluminum. In other words, achieving both prevention of corrosion and reduction of electromagnetic noise by using the nonmetallic conductive materials 3 as in the first embodiment is particularly useful in the case of using a heat exchanger in which the spontaneous potential of the refrigerant conduit is lower than the spontaneous potential of a peripheral material such as the housing 2.

Note that the installation location and shape of each conductive material 3 are not limited to that exemplified in the drawing. For example, the conductive materials 3 may be fixed to the housing floor panel 2a, the housing top panel 2b, or the like, or may be electrically connected to any surface of the heat exchanger 6. The shape of each conductive material 3 may be appropriately changed such that the conductive material 3 can be electrically connected to the housing 2 and the heat exchanger 6.

The entire heat exchanger 6 does not always need to be made of the second metal, and at least part of the heat exchanger 6 just needs to be made of the second metal. For example, the fins or the refrigerant conduits of the heat exchanger 6 just need to be made of the second metal at lowest.

The configurations set forth in the above embodiment show examples, and it is possible to combine the configurations with another known technique, and is also possible to partially omit or change the configurations without departing from the scope of the present disclosure.

Claims

1. An outdoor unit of an air conditioner, comprising: a housing, made of first metal, having a box shape;a heat exchanger disposed in the housing and fixed to the housing via a non-conductive material, at least part of the heat exchanger being made of second metal, the second metal being different in spontaneous potential from the first metal; anda conductive material made of nonmetal, the conductive material being disposed in the housing, whereinthe conductive material is fixed to the housing and electrically connected to the housing, and is electrically connected to the heat exchanger.

2. The outdoor unit of an air conditioner, according to claim 1, wherein the housing includes: a housing floor panel;a housing top panel disposed above the housing floor panel;a housing front panel configured to couple the housing floor panel with the housing top panel;a housing rear panel; andhousing side panels, whereinthe conductive material is fixed to at least one of the housing floor panel, the housing top panel, the housing front panel, the housing rear panel, and the housing side panels.

3. The outdoor unit of an air conditioner, according to claim 1, wherein a spontaneous potential of the first metal is higher than a spontaneous potential of the second metal.

4. The outdoor unit of an air conditioner, according to claim 1, wherein the first metal is iron or iron alloy, andthe second metal is aluminum or aluminum alloy.

5. The outdoor unit of an air conditioner, according to claim 1, wherein the heat exchanger is a parallel-flow heat exchanger.

6. The outdoor unit of an air conditioner, according to claim 2, wherein the heat exchanger is a parallel-flow heat exchanger.

7. The outdoor unit of an air conditioner, according to claim 3, wherein the heat exchanger is a parallel-flow heat exchanger.

8. The outdoor unit of an air conditioner, according to claim 4, wherein the heat exchanger is a parallel-flow heat exchanger.