WO2023119565A1

WO2023119565A1 - Outdoor unit for air conditioner

Info

Publication number: WO2023119565A1
Application number: PCT/JP2021/047910
Authority: WO
Inventors: 佳祐岩澤; 隆二百瀬; 喬太大塚; 健二廣瀬; 正則大井; 裕人竹内
Original assignee: 三菱電機株式会社
Priority date: 2021-12-23
Filing date: 2021-12-23
Publication date: 2023-06-29
Also published as: JPWO2023119565A1

Abstract

An outdoor unit (1) for an air conditioner comprises: a box-shaped housing (2) that is formed from a first metal, and has formed therein an air supply aperture for allowing outdoor air to flow in; a heat exchanger (6) that is at least partially formed from a second metal having a different standard electrode potential from the first metal, is positioned within the housing (2), and is fixed to the housing (2) via a non-conductive member; and a grille (3) that is positioned at a distance from the heat exchanger (6) and on the upstream side of the heat exchanger (6) in the airflow direction, is fixed to the housing (2) and electrically connected to the housing (2), and is formed from the first metal.

Description

outdoor unit of air conditioner

The present disclosure relates to an outdoor unit of an air conditioner that includes a housing and a heat exchanger.

As a conventional outdoor unit of an air conditioner, there is known one that includes a box-shaped housing and a heat exchanger arranged in the housing, and the heat exchanger and the housing are formed of dissimilar metals. . The types of metals used for the heat exchanger and housing are selected according to the required properties. For example, aluminum is generally used for heat exchangers that require high thermal conductivity, and iron is generally used for housings that require strength.

When the heat exchanger and housing, which are dissimilar metals, are brought into direct contact with each other, contact corrosion occurs in the metal with the lower standard electrode potential when moisture adheres to the contact point. In the following, galvanic corrosion is simply referred to as corrosion. As means for preventing corrosion, means for indirectly connecting the heat exchanger and the housing via a non-conductive member such as resin is known.

However, when such means are used, the non-conductive member electrically insulates the heat exchanger from the housing, resulting in parasitic capacitance between the heat exchanger and the housing. In addition, there is a problem that electromagnetic noise generated from an electronic substrate, a compressor, or the like arranged in the housing causes a change in voltage in the parasitic capacitance, and this voltage change causes further electromagnetic noise. In addition, the back of the housing is formed with an air supply port for inflowing outdoor air, and the heat exchanger is positioned facing the air supply port to exchange heat with the outdoor air. are placed in Electromagnetic noise is radiated to the outside of the housing from between the heat exchanger and the housing through the air supply port.

Therefore, technology is being developed to simultaneously solve the two challenges of preventing corrosion and reducing electromagnetic noise. For example, Patent Literature 1 discloses a technique in which a conductive connection member is interposed between a heat exchanger and a housing. The connection member includes a first connection portion that is formed of the same metal as the metal used for the heat exchanger and is in direct contact with the heat exchanger, and a housing that is formed of the same metal as the metal used for the housing. and a second connection portion that is in direct contact with the . An insulating layer is provided between the first connection portion and the second connection portion to electrically insulate the first connection portion and the second connection portion.

In the technique disclosed in Patent Document 1, a portion of the insulating layer is removed to partially bring the first connection portion and the second connection portion, which are dissimilar metals, into direct contact with each other, thereby ensuring electrical continuity and electromagnetic interference. While noise is reduced, by covering the contact points between the first connection portion and the second connection portion with a covering member such as a waterproof tape, the infiltration of moisture to the contact points is blocked and the corrosion of the metal is prevented. .

Japanese Patent No. 6583489

However, in the technique disclosed in Patent Document 1, the use of multiple types of metals for the connecting member, the provision of the insulating layer, and the use of the waterproof covering member result in a complicated structure. There are problems such as an increase in the number of components and an increase in the number of parts.

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

In order to solve the above-described problems and achieve the object, an outdoor unit of an air conditioner according to the present disclosure is formed with an air supply port for introducing outdoor air, and is made of a first metal. A box-shaped housing and at least a portion of which is formed of a second metal having a standard electrode potential different from that of the first metal, is arranged in the housing, and is fixed to the housing via a non-conductive member. an exchanger and a grid arranged upstream of the heat exchanger in the direction of air flow and spaced from the heat exchanger, fixed to and electrically connected to the housing and formed of a first metal; It has a body and

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

1 is an exploded perspective view schematically showing an outdoor unit of an air conditioner according to Embodiment 1. FIG. Fig. 2 is a front view showing the outdoor unit of the air conditioner according to the first embodiment, showing a state in which the housing front panel of the housing is removed; 1 is an exploded perspective view showing an electronic board box and an interface panel according to Embodiment 1; FIG. 4 is a perspective view showing a state in which the electronic board box and the interface panel shown in FIG. 3 are assembled; FIG. The right side view showing the outdoor unit of the air conditioner according to Embodiment 1. Sectional view along the VI-VI line shown in FIG. FIG. 2 is a rear view showing the lattice body according to Embodiment 1; Fig. 2 is a rear view showing the outdoor unit of the air conditioner according to the first embodiment, showing a state in which a grid is attached to the housing; Sectional view along line IX-IX shown in FIG. 1 is a perspective view schematically showing the heat exchanger according to Embodiment 1. FIG. 1 is a front view showing the heat exchanger according to Embodiment 1. FIG. FIG. 11 is an enlarged view of the main part of the heat exchanger shown in FIG. FIG. 2 is a schematic diagram showing, as an electric circuit, a transmission path of electromagnetic noise generated in the outdoor unit of the air conditioner according to Embodiment 1; FIG. 2 is a circuit diagram showing an equivalent circuit of a path along which a current that causes electromagnetic noise is transmitted in the outdoor unit of the air conditioner according to the first embodiment; FIG. 2 is a rear view of the outdoor unit of the air conditioner according to Embodiment 1, showing a state where the grid is removed and a location where electromagnetic noise is generated; FIG. 4 is a circuit diagram showing an equivalent circuit of a path through which a current that becomes electromagnetic noise is transmitted when the heat exchanger and the housing are brought into direct contact without an insulating member in the outdoor unit of the air conditioner according to the first embodiment. FIG. 2 is a rear view of the outdoor unit of the air conditioner according to Embodiment 1, showing a state where a grid is attached and a location where electromagnetic noise is generated;

Below, the outdoor unit of the air conditioner according to the embodiment will be described in detail based on the drawings.

Embodiment 1.
FIG. 1 is an exploded perspective view schematically showing an outdoor unit 1 of an air conditioner according to Embodiment 1. FIG. As shown in FIG. 1, an outdoor unit 1 of an air conditioner includes a housing 2, a lattice 3, a partition plate 4, a blower 5, a heat exchanger 6, two insulating members 7, and a compressor. 8 and an electronic board box 9. Hereinafter, the outdoor unit 1 of the air conditioner may be simply referred to as the outdoor unit 1 in some cases.

Hereinafter, when describing the direction of each component of the outdoor unit 1, the depth direction of the outdoor unit 1 is the X-axis direction, the height direction of the outdoor unit 1 is the Y-axis direction, and the width direction of the outdoor unit 1 is the Z-axis direction. do. The positive direction in the X-axis direction is forward, and the negative direction in the X-axis direction is backward. The + direction of the X-axis direction is the direction from the - side to the + side of the X-axis, and the - direction of the X-axis direction is the direction from the + side to the - side of the X-axis. In addition, the positive direction in the Y-axis direction is defined as upward, and the negative direction in the Y-axis direction is defined as downward. The + direction of the Y-axis is the direction from the - side to the + side of the Y-axis, and the - direction of the Y-axis is the direction from the + side to the - side of the Y-axis. Also, the positive direction of the Z-axis is defined as the right side, and the negative direction of the Z-axis direction is defined as the left side. The + direction of the Z-axis direction is the direction from the - side to the + side of the Z-axis, and the - direction of the Z-axis direction is the direction from the + side to the - side of the Z-axis. In the present embodiment, the side of the outdoor unit 1 where the airflow generated by the blower 5 is discharged to the outside is the front side, and the opposite side of the front side is the back side. An arrow Y shown in FIG. 1 represents the blowing direction of the airflow generated by the blower 5 .

FIG. 2 is a front view showing the outdoor unit 1 of the air conditioner according to Embodiment 1, showing a state in which the housing front panel 2c of the housing 2 is removed. In FIG. 2, the heat exchanger 6 is indicated by dot hatching for easy understanding. As shown in FIGS. 1 and 2 , the housing 2 is a box-shaped member that serves as the outer shell of the outdoor unit 1 . The housing 2 is made of a first metal. The first metal is preferably a metal with high strength. The first metal is, for example, iron or an iron alloy.

As shown in FIG. 1, the housing 2 has a housing floor panel 2a, a housing top panel 2b, a housing front panel 2c, and a housing side panel 2d. The housing floor panel 2 a constitutes the bottom surface of the outer shell of the outdoor unit 1 . The plan view shape of the housing floor panel 2a is a rectangle with rounded corners. The housing top panel 2b is arranged above the housing floor panel 2a and away from the housing floor panel 2a. The housing top surface panel 2b constitutes the ceiling surface of the outer shell of the outdoor unit 1. As shown in FIG. The planar view shape of the housing top panel 2b is the same as the planar view shape of the housing floor panel 2a.

The housing front panel 2c and the housing side panel 2d connect the housing floor panel 2a and the housing top panel 2b. The plan view shape of the housing front panel 2c is L-shaped. The housing front panel 2c includes a front panel main body portion 2e extending along the Z-axis direction and a front panel extending rearward from a left edge serving as one edge portion of the front panel main body portion 2e along the Z-axis direction. and an extension 2f. The front panel body 2e connects the front edge of the housing floor panel 2a and the front edge of the housing top panel 2b. The front panel main body portion 2 e constitutes the front surface of the outer shell of the outdoor unit 1 . The front panel extension 2f connects the left edge of the housing floor panel 2a and the left edge of the housing top panel 2b. The front panel extension 2f constitutes the left side of the outer shell of the outdoor unit 1. As shown in FIG. Hereinafter, the front panel extension 2f may also be referred to as the "casing side panel 2g". Although the front panel body 2e and the housing side panel 2g are integrally formed in this embodiment, they may be formed separately.

The planar view shape of the housing side panel 2d is L-shaped. The housing side panel 2d includes a side panel body portion 2h extending along the X-axis direction, and a side surface extending leftward from a rear edge portion serving as one edge along the X-axis direction of the side panel body portion 2h. and a panel extension 2i. The side panel body 2h connects the right edge of the housing floor panel 2a and the right edge of the housing top panel 2b. The side panel body portion 2h constitutes the right side surface of the outer shell of the outdoor unit 1. As shown in FIG. The side panel extension 2i connects part of the rear edge of the housing floor panel 2a and part of the rear edge of the housing top panel 2b. The side panel extension 2i forms part of the rear surface of the outer shell of the outdoor unit 1. As shown in FIG. Hereinafter, the side panel extension 2i may also be referred to as a "casing rear panel 2j". Although the side panel body portion 2h and the housing rear panel 2j are integrally formed in this embodiment, they may be formed separately. With the panels shown in FIG. 1 assembled, the left edge of the housing rear panel 2j and the rear edge of the housing side panel 2g are separated from each other.

The lattice body 3 is a metal member that is arranged away from the heat exchanger 6 on the upstream side of the heat exchanger 6 in the direction of air flow, is fixed to the housing 2, and is electrically connected to the housing 2. . In this specification, the term "electrically connected" between metal members means a state in which the metal members are in direct contact with each other and conduct, and a state in which the metal members are in contact with each other through a gap. included. The grid 3 is arranged between the left edge of the housing rear panel 2j and the rear edge of the housing side panel 2g. The grid 3 is arranged on the rear side of the heat exchanger 6 and away from the heat exchanger 6 . The grid 3 is made of the same first metal as the housing 2 .

As shown in FIG. 2, the partition plate 4 is a metal member that divides the inside of the housing 2 into a fan room 10 and an electric room 11. The fan chamber 10 and the electric chamber 11 are formed side by side in the Z-axis direction. The partition plate 4 extends in the Y-axis direction over the electronic board box 9 from the housing floor panel 2a. The partition plate 4 extends in the X-axis direction from the housing front panel 2c to the housing rear panel 2j shown in FIG.

The housing 2, grid 3, and partition plate 4 shown in FIG. 1 are made of the same kind of first metal. The portions where the housing 2, the lattice 3, and the partition plate 4 contact each other are joined by welding, screws, or the like. If the surface of each panel of the housing 2 is painted or the like and the electrical resistance of the surface of each panel is high, for example, part or all of the joints are masked in advance, or screws are screwed using serration screws. The electrical resistance of the surface of each panel can be lowered by peeling off the coating when tightening.

As shown in FIG. 2, the blower 5 is a device that is arranged in the fan room 10 and generates an air flow. The blower 5 includes a support 5a rising from the floor panel 2a of the enclosure, a fan motor 5b attached to the support 5a, and a propeller fan 5c attached to the rotating shaft of the fan motor 5b and rotating as the fan motor 5b rotates. and The upper end of the column 5a is fixed to the housing top panel 2b. A lower end portion of the column 5a is fixed to the housing floor panel 2a. The fan motor 5b is electrically connected via a fan drive wire 12 to an electronic board 9c, which will be described later. The fan motor 5b rotates when it receives a drive signal output from the electronic board 9c via the fan drive wire 12. As shown in FIG.

The heat exchanger 6 is a member that is arranged in the fan room 10 and performs heat exchange between the refrigerant and the outdoor air. Outdoor air to be taken in by 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 arranged inside the housing 2 and fixed to the housing 2 via an insulating member 7 that is a non-conductive member. At least part of the heat exchanger 6 is made of a second metal having a standard electrode potential different from that of the first metal. The second metal is preferably a metal with high thermal conductivity. The second metal is, for example, aluminum or an aluminum alloy. The standard electrode potential of the first metal is higher than the standard electrode potential of the second metal.

As shown in FIG. 1, the plan view shape of the heat exchanger 6 is L-shaped. The heat exchanger 6 extends forward along the X-axis direction after extending along the Z-axis direction. A portion of the heat exchanger 6 along the Z-axis direction is arranged behind the blower 5 . A portion of the heat exchanger 6 along the X-axis direction is arranged to the left of the blower 5 . The heat exchanger 6 and the blower 5 are spaced apart and electrically insulated, or are electrically insulated via an insulating member (not shown).

The heat exchanger 6, the housing front panel 2c, and the housing side panel 2d are electrically insulated by being spaced apart from each other, or are electrically insulated via an insulating member (not shown). effectively insulated. As shown in FIG. 2, the upper end of the heat exchanger 6 is fixed to the housing top panel 2b via an insulating member 7. As shown in FIG. A lower end portion of the heat exchanger 6 is fixed to the housing floor panel 2a via an insulating member 7 . Heat exchanger 6 is electrically insulated from housing top panel 2b and housing floor panel 2a. The heat exchanger 6 is arranged without being electrically connected to metal members such as the housing 2 , the grid 3 , the blower 5 and the like arranged around the heat exchanger 6 .

A material having electrical insulation such as resin is used as the material of the two insulating members 7 shown in FIG. Hereinafter, when distinguishing between the two insulating members 7, the insulating member 7 provided at the lower end of the heat exchanger 6 will be referred to as a first insulating member 7a, and the insulating member 7 provided at the upper end of the heat exchanger 6 will be referred to as a first insulating member 7a. The member 7 is called a second insulating member 7b. In this embodiment, a first insulating member 7a and a second insulating member 7b having the same planar shape and size as the heat exchanger 6 are used to cover the entire bottom surface and top surface of the heat exchanger 6. Although the heat exchanger 6 and the housing 2 are electrically insulated by covering, it is not intended to limit the means for electrically insulating the two members. For example, several pedestals made of an electrically insulating material are provided on the bottom surface of the heat exchanger 6, and the pedestals are interposed between the heat exchanger 6 and the housing floor panel 2a. good too. With such a configuration, the heat exchanger 6 and the housing floor panel 2a are separated from each other in the Y-axis direction, so that the heat exchanger 6 and the housing floor panel 2a can be electrically insulated.

As shown in FIG. 2 , the compressor 8 is a device that is arranged in the electric room 11 and compresses the refrigerant flowing through the heat exchanger 6 . The compressor 8 is arranged on the housing floor panel 2 a in the lower space of the electric room 11 . The compressor 8 is fixed to the housing floor panel 2a with screws or the like.

The electronic board box 9 is a member that houses an electronic board 9c such as a control board necessary for operating the outdoor unit 1. The electronic board box 9 is formed in a hollow rectangular parallelepiped shape. The electronic board box 9 is fixed to the upper end of the partition plate 4 and arranged across the fan room 10 and the electrical room 11 . A downwardly extending heat sink 9 d is attached to the portion of the electronic board box 9 that is located in the fan chamber 10 . The heat sink 9 d is exposed to the fan chamber 10 . The heat sink 9 d is cooled by the air flow generated by the blower 5 .

The part of the electronic board box 9 placed in the electrical room 11 is placed above the compressor 8 . A compressor drive wire 13 is connected to a portion of the electronic board 9c disposed in the electrical chamber 11 . The compressor 8 is electrically connected to the electronic substrate 9c via a compressor drive wire 13. As shown in FIG. Compressor 8 is driven when it receives a drive signal output from electronic board 9c via compressor drive wire 13 .

The electric room 11 is surrounded by the housing floor panel 2a, the partition plate 4, the housing side panel 2d, the electronic board box 9, and the housing front panel 2c and housing rear panel 2j shown in FIG. It has a waterproof structure that prevents water such as rainwater from entering from the outside of the housing 2 . A stop valve 17 is provided at the lower portion of the outer surface of the housing side panel 2d. The stop valve 17 serves as a terminal for connecting a refrigerant pipe connected to an indoor unit (not shown).

The compressor 8 and the stop valve 17 are connected to each other via multiple refrigerant pipes 18 . Compressor 8 and heat exchanger 6 are connected to each other via a plurality of refrigerant pipes 18 . A connecting portion 19 between the heat exchanger 6 and the refrigerant pipe 18 is arranged in the electric chamber 11 having a waterproof structure. By arranging the connecting portion 19 in the electrical chamber 11 in this way, it is possible to prevent the connecting portion 19 from coming into contact with moisture, and thus corrosion of the connecting portion 19 can be prevented. In order to further enhance the waterproof effect of the connecting portion 19, the connecting portion 19 may be waterproofed by winding a waterproof tape or the like. Although not specifically illustrated, the refrigerant pipe 18 is connected to valve devices such as a four-way valve for switching the direction of flow of the refrigerant and an expansion valve for expanding the refrigerant to a predetermined pressure. The connection form of the refrigerant pipe 18 is not limited to the illustrated example.

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

The interface panel 20 is made of the same first metal as the housing side panel 2d. Therefore, the interface panel 20 is joined to the housing side panel 2d with low electrical resistance. The interface panel 20 is connected to the signal ground of the electronic board 9c. The interface panel 20 has a ground connection point 20e to which the ground wire 16 is connected. Interface panel 20 is grounded via ground connection point 20 e and ground wire 16 . The housing 2 joined to the interface panel 20 and the partition plate 4 joined to the housing 2 are grounded through the ground connection point 20 e and the ground wire 16 . The heat exchanger 6 is electrically connected to the housing 2 via the connecting portion 19 to the refrigerant pipe 18 , the compressor 8 , etc., but is not directly short-circuited with the housing 2 and the partition plate 4 . In other words, heat exchanger 6 is indirectly short-circuited with housing 2 and partition plate 4 via compressor 8 or the like, and is not short-circuited by direct contact with housing 2 and partition plate 4 .

Next, the configuration of the outdoor unit 1 will be explained in more detail. First, the configurations of the electronic board box 9 and the interface panel 20 will be described with reference to FIGS. 3 and 4. FIG. FIG. 3 is an exploded perspective view showing electronic board box 9 and interface panel 20 according to the first embodiment. FIG. 4 is a perspective view showing a state in which the electronic board box 9 and the interface panel 20 shown in FIG. 3 are assembled.

As shown in FIG. 3, the electronic board box 9 includes a box-shaped lower box 9a opening upward, an upper lid 9b covering the upper opening of the lower box 9a, an electronic board 9c, and a heat sink 9d. there is The electronic board 9c is fixed inside the lower box 9a. The electronic board 9 c has an internal power line 15 connected to the terminal block 21 and a compressor drive wire 13 connected to the compressor 8 . Although illustration is omitted, the electronic board 9c has a heating element, a fan motor 5b, various power lines for operating other driving devices, and the like.

The heat sink 9d is fixed to the electronic board 9c while being in close contact with the electronic board 9c. The heat sink 9d serves to cool the heat generating elements of the electronic substrate 9c. The heating element is, for example, a power semiconductor represented by an IGBT (Insulated Gate Bipolar Transistor). The electronic board 9c to which the heat sink 9d is fixed is inserted into the lower box 9a through the upper opening of the lower box 9a. As shown in FIG. 4, part or all of the heat sink 9d is exposed to the outside of the lower box 9a through a hole 9e formed in the bottom wall of the lower box 9a.

The lower box 9a and the upper lid 9b shown in FIG. 3 are made of, for example, rubber, resin, metal such as iron, or a combination thereof. For example, when the lower box 9a and the upper lid 9b are made of metal, the electronic board 9c is covered with metal, so that the electromagnetic noise generated from the electronic board 9c does not reach the outside of the electronic board box 9. Radiation can be suppressed. Moisture such as rainwater splashing in the fan chamber 10 may enter the electric chamber 11 inside the electronic board box 9 through the hole 9e formed in the bottom wall of the lower box 9a. Therefore, in practice, the electronic board box is designed to prevent moisture from entering by devising the shape of the hole 9e and the shape of the lower box 9a, or by adding a new waterproof structure. 9 and the electric room 11 are ensured to be waterproof.

The interface panel 20 has an interface vertical wall 20a, an upper joint flange portion 20b, an interface horizontal 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 the upper end of the interface vertical wall 20a. The upper joining flange portion 20b is joined to the lower surface of the bottom wall of the lower box 9a. The interface lateral wall 20c extends horizontally in the Z-axis direction from the lower end of the interface vertical wall 20a. The lower joint flange portion 20d extends downward in the Y-axis direction from the tip portion of the interface lateral wall 20c. The lower joining flange portion 20d is joined to the inner surface of the housing side panel 2d shown in FIG. The interface panel 20 is fixed and electrically connected to the housing side panel 2d at the lower joint flange portion 20d. The interface panel 20 is fixed to the housing side panel 2d and the lower box 9a, respectively.

Next, the configuration of the right side surface of the outdoor unit 1 will be described with reference to FIG. 5 is a right side view showing the outdoor unit 1 of the air conditioner according to Embodiment 1. FIG.

An opening 2k that communicates the inside and outside of the housing 2 is formed in the housing side panel 2d. An interface cover 22 is detachably attached to the housing side panel 2d. The interface cover 22 can be opened and closed by attachment and detachment. The interface cover 22 covers the opening 2k when closed. The interface cover 22 opens the opening 2k when open. The interface panel 20 and the terminal block 21 installed in the electrical room 11 are visible and accessible through the opening 2k. Connection work of various power lines can be performed by opening the interface cover 22 and through the opening 2k.

The interface cover 22 serves to prevent moisture such as rainwater from entering the electrical room 11 while ensuring ventilation between the electrical room 11 and the outside of the housing 2 . The interface cover 22 is made of resin, metal such as iron, or a combination thereof. When the interface cover 22 is made of a metal such as iron and is joined to the housing side panel 2d in a state of low electrical resistance, the interface cover 22 closes the opening 2k so that the opening 2k is exposed to the housing. 2, the radiation of electromagnetic noise to the outside can be suppressed.

Although illustration is omitted, the interface cover 22 has a common hole for the purpose of ensuring ventilation between the electric room 11 and the outside of the housing 2 and allowing power lines to enter and exit the electric room 11 and the outside of the housing 2. is formed. Waterproofing means is provided in the common hole so that moisture such as rainwater does not enter the electric chamber 11 . As a waterproofing means, for example, there is a means to cover the gaps of the common holes with a sponge or make the common holes into a shutter structure.

Next, the configuration of the partition plate 4 will be described with reference to FIG. FIG. 6 is a cross-sectional view taken along line VI-VI shown in FIG. In FIG. 6, only the housing 2 is hatched with oblique lines for easy understanding.

The partition plate 4 has a first partition portion 4a and a second partition portion 4b connected to the rear end portion of the first partition portion 4a. An introduction hole 4c for introducing the end of the heat exchanger 6 in the Z-axis direction into the electric chamber 11 is formed in the second partition portion 4b. The heat exchanger 6 and the second partition portion 4b are made of different metals. In order to avoid contact between dissimilar metals, it is preferable, for example, to interpose a resin material between the heat exchanger 6 and the second partition portion 4b.

Next, the configuration of the grid 3 will be described with reference to FIG. FIG. 7 is a rear view showing the grid 3 according to Embodiment 1. FIG.

The lattice 3 has a fixed frame 31, a plurality of metal wires 32, a plurality of intersections 33, and a plurality of lattice connection portions 34. The lattice body 3 is a lattice member formed by crossing a plurality of metal wires 32 in the Y-axis direction and the Z-axis direction. The material of the lattice 3 is not particularly limited as long as it is the same first metal as the housing 2 .

The rear view shape of the fixed frame 31 is a square frame. The fixed frame 31 has a first vertical frame portion 31a, a second vertical frame portion 31b, a first horizontal frame portion 31c, and a second horizontal frame portion 31d. The first vertical frame portion 31a and the second vertical frame portion 31b extend along the Y-axis direction. The first vertical frame portion 31a and the second vertical frame portion 31b are arranged parallel to each other with a space therebetween in the Z-axis direction. The first horizontal frame portion 31c and the second horizontal frame portion 31d extend along the Z-axis direction. The first horizontal frame portion 31c and the second horizontal frame portion 31d are arranged parallel to each other with an interval in the Y-axis direction. The first horizontal frame portion 31c connects the upper end portion of the first vertical frame portion 31a and the upper end portion of the second vertical frame portion 31b. The second horizontal frame portion 31d connects the lower end portion of the first vertical frame portion 31a and the lower end portion of the second vertical frame portion 31b.

The metal wire 32 has a plurality of vertically extending first metal wires 32a and a plurality of horizontally extending second metal wires 32b. The first metal wire 32a extends along the Y-axis direction and bridges the first horizontal frame portion 31c and the second horizontal frame portion 31d. The plurality of first metal wires 32a are arranged parallel to each other at equal intervals A in the Z-axis direction. The second metal wire 32b extends along the Z-axis direction and bridges the first vertical frame portion 31a and the second vertical frame portion 31b. The plurality of second metal lines 32b are arranged parallel to each other with equal intervals B in the Y-axis direction. Hereinafter, the interval A may be referred to as the lattice interval A, and the interval B may be referred to as the lattice interval B.

The crossing portion 33 is a portion where the first metal wire 32a and the second metal wire 32b cross each other. The intersection portion 33 is a portion where the first metal wire 32a and the second metal wire 32b are fixed to each other and where the first metal wire 32a and the second metal wire 32b are electrically connected. be. The means for fixing the first metal wire 32a and the second metal wire 32b are, for example, welding and screws.

The lattice connection part 34 is a part where both ends along the extending direction of the metal wire 32 are fixed on the fixed frame 31 . The lattice connecting portion 34 is a portion where the metal wires 32 and the fixed frame 31 are fixed to each other and the metal wires 32 and the fixed frame 31 are electrically connected. Fixing means between the metal wire 32 and the fixed frame 31 is, for example, welding or screws.

The lattice spacing A and the lattice spacing B of the grid 3 are less than half the wavelength of the electromagnetic noise generated from inside the housing 2 . The grid 3 is arranged on the path of the air passing through the heat exchanger 6 towards the fan chamber 10 shown in FIG. It is Therefore, it is desirable to make the thickness of the metal wire 32 thin enough to ignore the bad influence of the air flow to the heat exchanger 6 and thick enough to reduce the impedance component such as electric resistance sufficiently. Moreover, it is desirable that the thickness of the fixed frame 31 is made thin to such an extent that the adverse effect of ventilation on the heat exchanger 6 can be ignored.

FIG. 8 is a rear view showing the outdoor unit 1 of the air conditioner according to Embodiment 1, showing a state in which the lattice 3 is attached to the housing 2. FIG. The housing 2 is formed with an air supply port 2m for introducing outdoor air. The air supply port 2m is an opening for allowing air outside the housing 2 to flow into the fan chamber 10 . The air supply port 2m is surrounded by the housing floor panel 2a, the housing rear panel 2j, the housing top panel 2b, and the housing side panel 2g.

The lattice body 3 is provided side by side with the housing rear panel 2j in the Z-axis direction. The lattice 3 is fixed to the housing floor panel 2a, the housing top panel 2b, the housing rear panel 2j, and the housing side panel 2g at the position of the air supply port 2m. The grid 3 and the housing 2 are electrically connected. The second horizontal frame portion 31d of the fixed frame 31 is fixed and electrically connected to the housing floor panel 2a. The first horizontal frame portion 31c of the fixed frame 31 is fixed and electrically connected to the housing top panel 2b. The first vertical frame portion 31a of the fixed frame 31 is fixed and electrically connected to the housing rear panel 2j. The second vertical frame portion 31b of the fixed frame 31 is fixed and electrically connected to the housing side panel 2g. Means for fixing the grid 3 and the housing 2 are, for example, welding and screws.

Next, with reference to FIG. 9, the configurations of the housing 2, the blower 5, the heat exchanger 6 and the grid 3 will be further described. FIG. 9 is a cross-sectional view taken along line IX-IX shown in FIG.

An exhaust port 2n is formed in the front panel body portion 2e of the housing front panel 2c. The exhaust port 2n is an opening for discharging the airflow generated by the blower 5 to the outside of the fan chamber 10. As shown in FIG. A bell mouth 23 is provided on the inner peripheral surface of the exhaust port 2n to improve ventilation between the inside and outside of the fan chamber 10. As shown in FIG. A front cover 24 having a ventilation hole 25 is attached in front of the exhaust port 2n in the front panel body 2e. The front cover 24 can prevent foreign matter from entering from the outside of the fan chamber 10 while ensuring ventilation between the inside and the outside of the fan chamber 10 . Foreign matter is, for example, dirt or dust. When the fan motor 5b rotates and the propeller fan 5c drives, the pressure in the fan chamber 10 becomes negative. The air that has flowed into the fan chamber 10 passes through the heat exchanger 6, becomes an air flow by the blower 5, and is discharged to the outside of the fan chamber 10 from the exhaust port 2n.

The upper end of the post 5a extends rearward along the housing top panel 2b. The upper end of the column 5a is fixed to the heat exchanger 6 via the second insulating member 7b on the back side inside the housing 2. As shown in FIG. The first horizontal frame portion 31c, which is the upper end portion of the lattice body 3, may be fixed to and electrically connected to the upper end portion of the support column 5a. It does not have to be. The heat exchanger 6 and the lattice body 3 are spaced apart from each other in the X-axis direction. Moreover, the heat exchanger 6 and the grid 3 are connected via a plurality of members including the insulating member 7 . The heat exchanger 6 and the grid 3 are arranged so as not to be electrically connected.

A downwardly folded top flange portion 2o is formed on the periphery of the housing top panel 2b. The top flange portion 2o is provided so as to cover the housing front panel 2c and the grid 3 from the outside of the housing 2. As shown in FIG. The top flange portion 2o is fixed to the housing front panel 2c and the lattice 3. As shown in FIG. Although not shown in FIG. 9, the top flange portion 2o is also provided so as to cover the housing side panel 2d from the outside of the housing 2, and is also fixed to the housing side panel 2d. It is desirable to electrically connect the lattice body 3 and the top flange portion 2o to minimize the gap between them.

A bottom flange portion 2p folded upward is formed on the periphery of the housing floor panel 2a. The bottom flange portion 2p is provided so as to be located on the inner side of the housing 2 between the housing front panel 2c and the grid 3. As shown in FIG. The bottom flange portion 2 p is fixed to the housing front panel 2 c and the lattice 3 . Although not shown in FIG. 9, the bottom flange portion 2p is also provided on the housing side panel 2d so as to be positioned inside the housing 2. As shown in FIG. The bottom flange portion 2p is also fixed to the housing side panel 2d. It is desirable to electrically connect the lattice body 3 and the bottom flange portion 2p to minimize the gap between them.

Next, the configuration of the heat exchanger 6 will be further described with reference to FIGS. 10 to 12. FIG. FIG. 10 is a perspective view schematically showing heat exchanger 6 according to the first embodiment. 11 is a front view showing the heat exchanger 6 according to Embodiment 1. FIG. FIG. 12 is an enlarged view of the main part of the heat exchanger 6 shown in FIG. 11. FIG.

As shown in FIG. 10, the heat exchanger 6 is a parallel flow heat exchanger in this embodiment. As shown in FIG. 11, the heat exchanger 6 has two

headers

6a and 6b, multiple refrigerant conduits 6c, and multiple fins 6d.

Both of the two

headers

6a and 6b are hollow metal members. Each

header

6a, 6b extends along the Y-axis direction. As shown in FIG. 10, the two

headers

6a and 6b are arranged apart from each other in the Z-axis direction and are arranged to be offset from each other in the X-axis direction. A refrigerant pipe 18 is connected to the header 6b.

Each refrigerant conduit 6c shown in FIG. 11 is a hollow metal member. A flat-shaped flat tube is used for each refrigerant|coolant conduit 6c, for example. The plurality of coolant conduits 6c are arranged at intervals in the Y-axis direction. Each refrigerant conduit 6c extends from one header 6a toward the other header 6b. The extending direction of each refrigerant conduit 6c is orthogonal to the Y-axis direction. One end in the extension direction of each refrigerant conduit 6c is connected to one header 6a, and the other end in the extension direction of each refrigerant conduit 6c is connected to the other header 6b. Each refrigerant conduit 6c communicates between one header 6a and the other header 6b.

The fin 6d is a plate-like member made of metal. The fins 6d are arranged between adjacent refrigerant conduits 6c. The shape of the fins 6d is not particularly limited, but in this embodiment, the fins 6d have a corrugated shape protruding upward and downward alternately. That is, corrugated fins are used for the fins 6d in this embodiment. As shown in FIG. 12, the fins 6d are in contact with each of the adjacent refrigerant conduits 6c and joined by welding or the like.

A coolant flows inside the

headers

6a and 6b and the coolant conduit 6c shown in FIG. One of the two

headers

6a, 6b serves to distribute refrigerant to each of the plurality of refrigerant conduits 6c. The other of the two

headers

6a and 6b serves to merge the refrigerants flowing out from each of the plurality of refrigerant conduits 6c. The refrigerant conduit 6c serves to exchange heat between the refrigerant and the outdoor air. That is, heat is exchanged between the refrigerant flowing inside the refrigerant conduit 6c and the outdoor air flowing around the refrigerant conduit 6c. The fins 6d play a role of promoting heat exchange between the refrigerant and the outdoor air.

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

As shown in FIG. 2, when electric power is supplied from the external AC power line 14 to the electronic board 9c via the internal power line 15, the electronic board 9c enters a standby state. When the electronic board 9c receives an operation start command signal from the indoor unit via a communication signal line between the indoor unit and the outdoor unit 1 (not shown), the operation of the outdoor unit 1 is started. Specifically, the electronic board 9c outputs a drive signal to the fan motor 5b through the fan drive wire 12 to drive the fan motor 5b. Further, the electronic board 9 c outputs another drive signal to the compressor 8 through the compressor drive wire 13 to drive the compressor 8 . At this time, the driving signal output from the electronic board 9c is generally a rectangular wave pulse generated by switching of the power semiconductor. Therefore, the drive signal contains high-frequency components such as switching noise of power semiconductors and harmonic components of rectangular wave pulses, which are not essentially necessary for driving the AC motors of the compressor 8 and the fan motor 5b. Such a high-frequency component becomes an electromagnetic noise source, and becomes one of the causes of radiation of the electromagnetic noise to the outside of the housing 2 through a transmission path, which will be described later.

FIG. 13 is a schematic diagram showing a transmission path of electromagnetic noise generated in the outdoor unit 1 of the air conditioner according to Embodiment 1 as an electric circuit. In FIG. 13, the heat exchanger 6 is indicated by dot hatching for easy understanding. For example, when a three-phase motor is used as the AC motor of the compressor 8, the electromagnetic noise generated in the electronic board 9c passes through the neutral point 8d of the three-phase motor windings to the motor windings 8a and the compressor. It is transmitted to the housing of the compressor 8 through the parasitic capacitance 8b existing between the housing of the compressor 8 and the housing of the compressor 8. Part of the electromagnetic noise transmitted to the housing of the compressor 8 is returned to the electronic board 9c after being transmitted to the housing floor panel 2a. However, since there is an impedance component 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 transferred to the refrigerant piping 18. is transmitted to the heat exchanger 6 through the

The characteristics of the parasitic impedance component of the heat exchanger 6 differ depending on the structure of the heat exchanger 6. Here, as an example, it is assumed that the heat exchanger 6 is a parallel flow type heat exchanger provided with fins 6d and flat refrigerant conduits 6c shown in FIG. 27 are combined as shown in FIG. 13 as an example of an equivalent circuit. A parasitic impedance component such as the parasitic inductance 27 of the heat exchanger 6 exists in a complicated manner as a distributed constant circuit as shown in FIG. Since the heat exchanger 6 and the housing 2 are electrically insulated by the first insulating member 7a and the second insulating member 7b, there is a parasitic capacitance 26a between the heat exchanger 6 and the housing 2. , 26b are generated. That is, a parasitic capacitance 26a is generated between the heat exchanger 6 and the housing floor panel 2a, and a parasitic capacitance 26b is generated between the heat exchanger 6 and the housing top panel 2b. The

parasitic capacitances

26a and 26b are generated on the electromagnetic noise transmission path.

FIG. 14 is a circuit diagram showing an equivalent circuit of the path along which current that causes electromagnetic noise is transmitted in the outdoor unit 1 of the air conditioner according to Embodiment 1. As shown in FIG. The electromagnetic noise transmitted from the electronic board 9c through the compressor 8 to the heat exchanger 6 and the housing 2 shown in FIG. 26a and 26b, and furthermore, resonance is generated with a parasitic impedance component such as a parasitic inductance 28 that each panel of the housing 2 has. The heat exchanger 6 and the housing floor panel 2a are electrically insulated by the first insulating member 7a shown in FIG. 2b are electrically insulated, voltage changes occur in the

parasitic capacitances

26a and 26b due to resonance.

FIG. 15 is a rear view of the outdoor unit 1 of the air conditioner according to Embodiment 1, showing a state in which the lattice 3 is removed and a location where electromagnetic noise is generated. In FIG. 15, the heat exchanger 6 is hatched for easy understanding. Between the heat exchanger 6 and each panel of the housing 2, gaps G1, G2, G3 and G4 are formed to ensure electrical insulation. In FIG. 15, the respective positions of the gaps G1, G2, G3 and G4 are surrounded by dashed lines. Although FIG. 15 shows that there are no gaps G1, G2, G3, and G4 between the heat exchanger 6 and the housing 2, the gaps G1, G2, G3, and G4 actually extend so as to surround the four sides of the heat exchanger 6. There are elongated gaps G1, G2, G3 and G4. The gaps G1, G2, G3, and G4 are locations where electromagnetic noise is generated. 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

parasitic capacitances

26a and 26b shown in FIG. As a result, the gaps G1, G2, G3 and G4 function as slot antennas and further generate electromagnetic noise in response to changes in the voltage applied across the gaps G1, G2, G3 and G4. Electromagnetic noise generated in the gaps G1, G2, G3, and G4 is radiated to the outside of the housing 2 through the air supply port 2m.

FIG. 16 shows that in the outdoor unit 1 of the air conditioner according to Embodiment 1, when the heat exchanger 6 and the housing 2 are brought into direct contact without the insulating member 7, a current that becomes electromagnetic noise is transmitted. FIG. 3 is a circuit diagram in which a path is converted into an equivalent circuit; By removing the first insulating member 7a and the second insulating member 7b shown 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 shown in FIG. 16,

parasitic capacitances

26a and 26b generated between the heat exchanger 6 and each panel of the housing 2 are short-circuited. 16 between the heat exchanger 6 and the housing floor panel 2a and between the heat exchanger 6 and the housing top panel 2b shown in FIG. No voltage change occurs through the gaps G1, G2, G3, and G4, and electromagnetic noise does not occur.

When the heat exchanger 6 and the housing 2 shown in FIG. 15 are made of dissimilar metals, the gaps G1, G2, G3 , G4 can prevent the generation of electromagnetic noise and reduce the radiation of electromagnetic noise to the outside of the housing 2. occurs. On the other hand, if the insulating member 7 is provided between the heat exchanger 6 and the housing 2, the corrosion of the heat exchanger 6 having a low standard electrode potential can be prevented at the contact point between the heat exchanger 6 and the housing 2. , electromagnetic noise is generated in the gaps G1, G2, G3, and G4, and the radiation amount of the electromagnetic noise to the outside of the housing 2 increases.

FIG. 17 is a rear view of the outdoor unit 1 of the air conditioner according to Embodiment 1, showing a state in which the grid 3 is attached and locations where electromagnetic noise is generated. In FIG. 17, the heat exchanger 6 is indicated by dot hatching for easy understanding. In the present embodiment, the outdoor unit 1 is arranged upstream of the heat exchanger 6 in the direction of air flow, away from the heat exchanger 6, fixed to the housing 2, and electrically connected to the housing 2. It has a grid 3 made of metal. As a result, the gaps G1, G2, G3 and G4 are divided by the lattice spacings A and B by the lattice body 3. As shown in FIG. Therefore, the radiation of electromagnetic noise to the outside of the housing 2 from the gaps G1, G2, G3, and G4 via the air supply port 2m is suppressed, and the amount of electromagnetic noise radiated to the outside of the housing 2 can be reduced. can. The frequency of the electromagnetic noise whose radiation to the outside of the housing 2 is suppressed is determined by the lattice intervals A and B between adjacent metal wires 32 .

On the other hand, in the present embodiment, as shown in FIGS. 15 and 17, the outdoor unit 1 includes a box-shaped housing 2 made of a first metal and at least a portion of which is made of the first metal. is a heat exchanger 6 made of a second metal having a different standard electrode potential, arranged in the housing 2 and fixed to the housing 2 via an insulating member 7, and arranged away from the heat exchanger 6 and a lattice 3 . As a result, the heat exchanger 6 and the housing 2 are not electrically connected, and the heat exchanger 6 and the grid 3 are not electrically connected. Therefore, corrosion due to contact between dissimilar metals can be prevented. Further, in the present embodiment, since the grid 3 is made of the same first metal as the housing 2, corrosion due to contact between the grid 3 and the housing 2 can be prevented. Therefore, in the present embodiment, corrosion prevention and electromagnetic noise reduction can be realized at the same time simply by arranging the metal lattice 3 and the non-conductive insulating member 7 . That is, it is possible to achieve both corrosion prevention and electromagnetic noise reduction with a cheaper and simpler structure than conventional ones.

In the present embodiment, the standard electrode potential of the first metal is higher than the standard electrode potential of the second metal, so that when heat exchanger 6 is electrically connected to housing 2 and grid 3, would cause corrosion to occur in the heat exchanger 6 made of the second metal. In this regard, in the present embodiment, since the heat exchanger 6 is not electrically connected to the housing 2 and the lattice 3 as described above, the corrosion of the heat exchanger 6 can be prevented.

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

In the present embodiment, the lattice intervals A and B of the lattice body 3 are less than half the wavelength of the electromagnetic noise generated from the inside of the housing 2, so that the electromagnetic noise can be further reduced. can be done.

In this embodiment, the grid 3 is fixed to the housing floor panel 2a, the housing top panel 2b, the housing rear panel 2j, and the housing side panel 2g. Therefore, the contact resistance and parasitic inductance 28 of the housing 2 can be reduced. Therefore, the electromagnetic noise transmitted to the electronic board 9c, the compressor 8, and each panel of the housing 2, that is, the noise terminal voltage, the interference power intensity, etc., can be reduced. The lattice 3 may be fixed to at least one of the housing floor panel 2a, the housing top panel 2b, the housing rear panel 2j, and the housing side panel 2g.

Conventional heat exchangers include serpentine heat exchangers and aluminum parallel flow heat exchangers. Both serpentine heat exchangers and parallel flow heat exchangers have fins and refrigerant conduits. In a serpentine heat exchanger, it is common to use aluminum for the fins and copper for the refrigerant conduits. When iron is used as the material of the housing 2, the magnitude relationship of the standard electrode potentials of the respective metals is aluminum<iron<copper. In other words, the magnitude relationship of the standard electrode potentials of the metal members is fin<casing 2<refrigerant conduit. If the fins and refrigerant conduits of the serpentine heat exchanger are brought into direct contact with the housing 2 and moisture adheres to the contact points, the fins having a lower standard electrode potential than the housing 2 will corrode. Corrosion does not occur in coolant conduits having a higher standard electrode potential than housing 2, although this may occur.

On the other hand, in a parallel-flow heat exchanger made of aluminum, since aluminum is used as the material for the fins and refrigerant conduits, if iron is used as the material for the housing 2, both the fins and the refrigerant conduits will corrode. may occur. If the refrigerant conduit is corroded and perforated, the refrigerant in the refrigerant conduit leaks into the atmosphere. Leakage of the refrigerant into the atmosphere impairs the cooling and heating function of the air conditioner. In this way, parallel flow type heat exchangers made of aluminum are greatly affected by corrosion, so it is very important to take measures to prevent corrosion. It is necessary to take Therefore, achieving both corrosion prevention and electromagnetic noise reduction by using the lattice 3 and the insulating member 7 as in the present embodiment is difficult due to corrosion as in parallel flow type heat exchangers made of aluminum. It is particularly useful when using a heat exchanger that has a large adverse effect. In other words, achieving both corrosion prevention and electromagnetic noise reduction by using the lattice 3 and the insulating member 7 as in the present embodiment means that the standard electrode potential of the refrigerant conduit is equal to that of the surrounding members such as the housing 2. It is particularly useful with heat exchangers below the standard electrode potential of .

The configuration of the lattice body 3 is not limited to the example shown in FIG. For example, the metal wire 32 may be directly fixed to the housing 2 without the grid 3 having the fixed frame 31 . Further, it is not essential that all four frame portions of the fixed frame 31 are electrically connected to the housing 2, and at least one of the four frame portions of the fixed frame 31 is electrically connected to the housing 2. It is good if there is. Even in this way, the same effects as those of the first embodiment can be obtained.

In the present embodiment, the fixed frame 31 in the shape of a square frame is exemplified, but it is not essential that the fixed frame 31 has four frame portions. For example, the fixed frame 31 may not have the second horizontal frame portion 31d, and one end of the first metal wire 32a in the Y-axis direction may be a free end without being fixed to the fixed frame 31. FIG. In this way, some electromagnetic noise may be radiated from the lower end of the lattice 3, but since the lower end of the lattice 3 is close to the installation surface such as the ground, the adverse effect on the electromagnetic noise is limited. , the same effects as those of the first embodiment can be obtained.

The method of manufacturing the grid 3 is not particularly limited. As a method of manufacturing the lattice body 3, for example, a method of fixing a metal wire 32 formed separately from the fixed frame 31 to the fixed frame 31 may be used, or a method of punching sheet metal is used to attach the fixed frame 31 and the metal wires 32 to each other. and may be integrally molded. By integrally molding the fixing frame 31 and the metal wire 32 in this way, the outdoor unit 1 can be manufactured by a simpler method at a lower cost.

The entire heat exchanger 6 need not be made of the second metal, and at least part of the heat exchanger 6 should be made of the second metal. For example, at least one of the fins of the heat exchanger 6 and the refrigerant conduit should be made of the second metal.

The configuration shown in the above embodiment is an example, and can be combined with another known technique, and part of the configuration can be omitted or changed without departing from the scope of the invention. It is possible.

1 outdoor unit of air conditioner, 2 housing, 2a housing floor panel, 2b housing top panel, 2c housing front panel, 2d housing side panel, 2e front panel main body, 2f front panel extension, 2g housing side panel, 2h side panel main body, 2i side panel extension, 2j housing rear panel, 2k opening, 2m air supply port, 2n exhaust port, 2o top flange, 2p bottom flange, 3 grating body, 4 partition plate, 4a first partition, 4b second partition, 4c introduction hole, 5 blower, 5a strut, 5b fan motor, 5c propeller fan, 6 heat exchanger, 6a, 6b header, 6c refrigerant Conduit 6d Fin 7 Insulating member 7a First insulating member 7b Second insulating member 8 Compressor 8a Motor winding 8b, 26a, 26b Parasitic capacitance 8c Contact resistance 8d Three-phase motor winding Neutral point, 9 electronic board box, 9a lower box, 9b upper lid, 9c electronic board, 9d heat sink, 9e hole, 10 fan chamber, 11 electric room, 12 fan drive wire, 13 compressor drive wire, 14 external AC power line, 15 Internal power line, 16 Ground line, 17 Stop valve, 18 Refrigerant pipe, 19 Connection, 20 Interface panel, 20a Interface vertical wall, 20b Upper joint flange, 20c Interface lateral wall, 20d Lower joint flange, 20e Ground connection point , 21 terminal block, 22 interface cover, 23 bell mouth, 24 front cover, 25 ventilation hole, 27, 28 parasitic inductance, 31 fixed frame, 31a first vertical frame portion, 31b second vertical frame portion, 31c first 31d second horizontal frame portion 32 metal wire 32a first metal wire 32b second metal wire 33 intersection portion 34 grid connection portion.

Claims

a box-shaped housing formed of a first metal and having an air supply port for introducing outdoor air;
a heat exchanger at least partially formed of a second metal having a standard electrode potential different from that of the first metal, arranged in the housing and fixed to the housing via a non-conductive member;
arranged apart from the heat exchanger upstream of the heat exchanger in the air flow direction, fixed to the housing and electrically connected to the housing, and formed of the first metal a grid with
The outdoor unit of an air conditioner equipped with
The housing comprises a housing floor panel, a housing top panel disposed above the housing floor panel and away from the housing floor panel, and the housing floor panel and the housing. having a housing rear panel and a housing side panel that are connected to the top panel,
2. The air conditioner according to claim 1, wherein the grid is fixed to at least one of the housing floor panel, the housing top panel, the housing rear panel and the housing side panel. Outdoor unit.
The outdoor unit of the air conditioner according to claim 1 or 2, wherein the standard electrode potential of the first metal is higher than the standard electrode potential of the second metal.
the first metal is iron,
The outdoor unit for an air conditioner according to any one of claims 1 to 3, wherein the second metal is aluminum.
The outdoor unit of the air conditioner according to any one of claims 1 to 4, wherein the heat exchanger is a parallel flow type heat exchanger.
The outdoor unit of the air conditioner according to any one of claims 1 to 5, wherein a lattice interval of the lattice body is half or less of a wavelength of electromagnetic noise generated from inside the housing. .