Electrical device

Abstract

In the present invention, an electronic substrate unit (9), which is for supplying power to a compressor (5) and on which a power conversion circuit (13) is formed, is accommodated within an outdoor unit housing (3) of an air conditioner outdoor unit (1). The electronic substrate unit (9) is provided with a substrate body (15) and a metal plate (17). The electronic substrate unit (9) is disposed so as to face the outdoor unit housing (3) with an interval therebetween. The metal plate (17) on the electronic substrate unit (9) and the outdoor unit housing (3) are electrically connected via a connection body (31). A first connected part (33), to which one end of the connection body (31) is connected, is formed on the electronic substrate unit (9). A second connected part (35), to which the other end of the connection body (31) is connected, is formed on the outdoor unit housing (3).

Description

Electrical Equipment

[0001] The present disclosure relates to electrical equipment.

[0002] Some electrical devices are equipped with power conversion circuits. One such electrical device is an outdoor air conditioner unit used in an air conditioner. The outdoor air conditioner unit's housing contains a compressor, an electronic circuit board, a terminal block, a fan, and other components. The electronic circuit board has a power conversion circuit such as an inverter circuit. Power supplied from an external power source to the electronic circuit board via the terminal block is converted to the desired power by the power conversion circuit and then supplied to the compressor, etc.

[0003] Power conversion circuits such as inverter circuits formed on the electronic board are sources of electromagnetic noise. The generated electromagnetic noise propagates to an external power source. The electromagnetic noise propagates through two propagation paths: one via wiring connected to the electronic board, and the other via the outdoor unit housing, which is at ground potential. Patent Document 1 proposes a method for suppressing electromagnetic noise propagating through the outdoor unit housing.

[0004] Japanese Patent Application Laid-Open No. 2015-117906

[0005] Patent Document 1 proposes a method of grounding a terminal block attached to the outdoor unit housing via wiring connected to the terminal block. Wiring is susceptible to external electromagnetic fields. Air conditioner outdoor units are required to be less susceptible to external electromagnetic fields.

[0006] The present disclosure has been made as part of such development, and its purpose is to provide an electric device equipped with a power conversion circuit that is less susceptible to the effects of external electromagnetic fields.

[0007] The electrical device according to the present disclosure is an electrical device equipped with a power conversion circuit, and includes a conductive housing, an electronic board, and a connector. The electronic board is housed in the conductive housing and includes a power conversion circuit and a noise filter. The connector has a first end and a second end, and electrically connects the electronic board to the conductive housing. The electronic board includes a board main body and a conductor plate. The conductor plate is arranged on the board main body and electrically connected to the conductive housing. The electronic board has a first connected portion to which the first end of the connector is connected. The conductive housing has a second connected portion to which the second end of the connector is connected. The electronic board is disposed facing the conductive housing with a spacing member interposed between the electronic board and the conductive housing. When the first end of the connector is connected to the first connected portion, the first end is electrically connected to the conductor plate, and when the second end of the connector is connected to the second connected portion, the second end is electrically connected to the conductive housing.

[0008] In the electrical device according to the present disclosure, the conductor plate arranged on the electronic board is electrically connected to the conductive housing via a connector. The connector is disposed between the electronic board and the conductive housing, with a spacing member interposed between the electronic board and the conductive housing, and the electronic board is positioned as close as possible to the conductive housing. This shortens the length of the connector, which is susceptible to external electromagnetic waves. As a result, the electrical device can be prevented from being affected by external electromagnetic fields.

[0009] 1 is a perspective view schematically illustrating the structure of an air conditioner outdoor unit as electrical equipment according to each embodiment. FIG. 1 is a partial perspective view conceptually illustrating a structure for electrically connecting a metal plate arranged on an electronic board to an outdoor unit housing in each embodiment. FIG. 2 is a partial exploded perspective view illustrating a connection portion on the electronic board side in an air conditioner outdoor unit as electrical equipment according to embodiment 1. FIG. 3 is a partial exploded perspective view illustrating a connection portion on the outdoor unit housing side in the same embodiment. FIG. 4 is a partial side view including a cross section taken along the cross section line V-V shown in FIG. 2 in the same embodiment. FIG. 5 is a partial exploded perspective view illustrating a structure for electrically connecting a metal plate arranged on an electronic board to an outdoor unit housing in an air conditioner outdoor unit as electrical equipment according to embodiment 2. FIG. 6 is a partial cross section taken along the cross section line VII-VII shown in FIG. 6 in the same embodiment. FIG. 7 is a partial exploded perspective view illustrating a structure for electrically connecting a metal plate arranged on an electronic board to an outdoor unit housing in an air conditioner outdoor unit as electrical equipment according to embodiment 3. FIG. 8 is a partial cross section taken along the cross section line IX-IX shown in FIG. 8 in the same embodiment. 11 is a partial exploded perspective view showing a structure for electrically connecting a metal plate arranged on an electronic board to an outdoor unit housing in an air conditioner outdoor unit as an electrical device according to Embodiment 4. FIG. 12 is a partial cross-sectional view taken along the cross-sectional line XI-XI shown in FIG. 10 in the same embodiment. FIG. 13 is a perspective view schematically showing the structure of a modified example of an air conditioner outdoor unit as an electrical device according to each embodiment.

[0010] First, an example of an outdoor unit for an air conditioner used in an air conditioner will be described as an example of electrical equipment according to each embodiment. As shown in Fig. 1, the outdoor unit 1 for an air conditioner has an outdoor unit housing 3 as a conductive housing, and houses a compressor 5 for compressing a refrigerant, an electronic board 9 and a terminal block 19 for supplying power to the compressor 5, a fan 7, etc.

[0011] The electronic board 9 is formed with a power conversion circuit 13 such as an inverter circuit, a noise filter 11, etc. A terminal block 19 is disposed on a metal member 21. The metal member 21 is electrically connected to the outdoor unit housing 3. A plurality of wires 23 electrically connected to an external power source (not shown) are connected to the terminal block 19. The terminal block 19 and the electronic board 9 are electrically connected by a plurality of wires 27. The electronic board 9 and the compressor 5 are electrically connected by a cable 29.

[0012] Electric power is sent from an external power source through wiring 23, terminal block 19, and wiring 27 to electronic board 9. In electronic board 9, the sent electric power flows through noise filter 11 and power conversion circuit 13 and is converted into desired electric power. The converted electric power flows through cable 29 and is supplied to compressor 5 and the like. One of wires 23 is electrically connected to metal member 21 as ground wire 25.

[0013] The positional relationship between the electronic board section 9 and the outdoor unit housing 3 will be described in more detail. The electronic board section 9 has a board main body 15. The power conversion circuit 13 and other components are formed on the board main body 15. The electronic board section 9 is disposed so as to face the outdoor unit housing 3. The electronic board section 9 and the outdoor unit housing 3 are disposed with a gap between them.

[0014] A plurality of metal plates for configuring an electric circuit are arranged in the board body 15. Of the plurality of metal plates, FIG. 1 shows metal plate 17, which is required to be electrically connected to the outdoor unit housing 3. Electromagnetic noise generated in the power conversion circuit 13 propagates from metal plate 17 to the outdoor unit housing 3. The metal plate 17 may be formed on either of the opposing main surfaces of the board body 15. In addition, in the case of an electronic board unit 9 in which a plurality of board bodies 15 are stacked, the metal plate 17 may be disposed between the stacked board bodies 15.

[0015] 1 shows the metal plate 17 disposed on the main surface of the board body 15 that faces the outdoor unit housing 3, in order to more clearly show the arrangement structure. In the air conditioning outdoor unit 1, the electronic board section 9 and the outdoor unit housing 3 are disposed opposite each other with a minimum necessary distance between them, via a spacing member, in order to avoid unexpected risks such as an electrical short circuit from parts other than the metal plate 17 that are required to be electrically connected to the outdoor unit housing 3.

[0016] Next, the concept of the structure including the connector 31 (see FIG. 2 ) that electrically connects the electronic board 9 and the outdoor unit housing 3 will be described. As shown in FIG. 2 , the metal plate 17 and the outdoor unit housing 3 are electrically connected via the connector 31. The connector 31 has one end and the other end. A first connected portion 33 to which one end of the connector 31 is connected is formed on the metal plate 17 (electronic board 9). A second connected portion 35 to which the other end of the connector 31 is connected is formed on the outdoor unit housing 3.

[0017] 2, in order to more clearly show the arrangement structure including the connector 31 and the metal plate 17, an exploded view is shown in which the metal plate 17 is arranged on the main surface of the board body 15 opposite to the main surface facing the outdoor unit housing 3. The structure including the connector 31 will be specifically described below.

[0018] Embodiment 1. As an example of electrical equipment according to embodiment 1, an air conditioning outdoor unit used in an air conditioner will be described. Here, a wiring member 43 is used as the connector 31. A structure including the wiring member 43 will be specifically described. As shown in FIG. 3 , a female connector 42 is connected to one end of the wiring member 43. A male connector 41 is attached to the electronic board 9 as the first connected portion 33. The male connector 41 is electrically connected to the metal plate 17. The female connector 42 is connected to the male connector 41.

[0019] As shown in Fig. 4, a crimp terminal 44 is connected to the other end of the wiring member 43. A threaded hole 4 is formed in the outdoor unit housing 3 as a second connected portion. A screw 45 is inserted into the crimp terminal 44. The screw 45 is threaded into the threaded hole 4, thereby fixing the crimp terminal 44 to the outdoor unit housing 3.

[0020] 5 shows a state in which the metal plate 17 and the outdoor unit housing 3 are electrically connected by a wiring member 43. As shown in FIG. 5, in this case, a spacing member 37 is arranged between the electronic board unit 9 and the outdoor unit housing 3 in order to keep the electronic board unit 9 and the outdoor unit housing 3 as close as possible to each other.

[0021] In the air conditioner outdoor unit 1 as the electrical device described above, the metal plate 17 arranged on the electronic board 9 is electrically connected to the outdoor unit housing 3 via the wiring member 43. The wiring member 43 is arranged between the electronic board 9 and the outdoor unit housing 3, with the electronic board 9 and the outdoor unit housing 3 being as close as possible to each other. This allows the length of the wiring member 43, which is considered to be susceptible to the influence of external electromagnetic fields, to be set to the shortest length. As a result, the air conditioner outdoor unit 1 can be prevented from being affected by external electromagnetic fields.

[0022] 5 and other figures show one wiring member 43 electrically connecting the metal plate 17 (electronic board section 9) and the outdoor unit housing 3, but multiple wiring members 43 may be provided. From the viewpoint of suppressing the influence of external electromagnetic fields, it is considered desirable to provide one wiring member 43. Furthermore, it is desirable for the wiring member 43 to be thick and short.

[0023] Although the case where the other end of the wiring member 43 is fixed to the outdoor unit housing 3 by the crimp terminal 44 and the screw 45 has been described, the method for fixing the other end of the wiring member 43 to the outdoor unit housing 3 is not limited to this. Instead of the crimp terminal 44 and the screw 45, for example, a dedicated terminal may be used.

[0024] Furthermore, although the case where one end of the wiring member 43 is electrically connected to the metal plate 17 by the female connector 42 and the male connector 41 has been described, the method of electrically connecting one end of the wiring member 43 to the metal plate 17 is not limited to this. For example, a through hole may be provided that penetrates the substrate main body 15 including the metal plate 17, and a wiring member that is slightly thicker than the opening diameter of the through hole may be used as the wiring member 43, and one end of the wiring member may be inserted into the through hole.

[0025] Furthermore, in addition to the wiring member 43, for example, a plate-shaped conductive member may be applied as the connector 31. In this case, a first connected portion 33 corresponding to the plate-shaped conductive member is formed on the electronic board 9, and a second connected portion 35 corresponding to the plate-shaped conductive member is formed on the outdoor unit housing 3.

[0026] Embodiment 2. An example of an air conditioner outdoor unit 1 as an electrical device according to embodiment 2 will now be described. As shown in Figures 6 and 7, a screw 51 (male screw) is used as a connector 31 that electrically connects a metal plate 17 and an outdoor unit housing 3. Note that Figure 6 shows an exploded view to more clearly illustrate the structure.

[0027] An opening 10 is formed in the board main body 15 including the metal plate 17 as a first connected portion 33, through which a screw 51 is inserted. A threaded hole 4 is formed in the outdoor unit housing 3, into which the screw 51 is threaded. The size of the threaded hole 4 is, for example, approximately M8. A sheet-like insulating material 38 is interposed between the electronic board portion 9 and the outdoor unit housing 3. Note that the rest of the configuration is the same as that of the air conditioning outdoor unit 1 shown in Figures 1 and 2, so the same reference numerals are used for the same members, and descriptions thereof will not be repeated unless necessary.

[0028] 6 , the metal plate 17 is electrically connected to the outdoor unit housing 3 by inserting screws 51 into openings 10 formed in the electronic board 9 and through holes formed in the insulating material 38, and then threading the screws 51 into threaded holes 4 formed in the outdoor unit housing 3. The electronic board 9 is also firmly fixed to the outdoor unit housing 3 by the screws 51.

[0029] 7 , a gap corresponding to the thickness of a sheet-like insulating material 38 is maintained between the electronic board unit 9 and the outdoor unit housing 3. The thickness of the insulating material 38 is set to a thickness that avoids unexpected risks, such as an electrical short circuit from a portion other than the metal plate 17, between the electronic board unit 9 and the outdoor unit housing 3.

[0030] In the air conditioner outdoor unit 1 as the electrical device described above, the metal plate 17 arranged on the electronic board 9 is electrically connected to the outdoor unit housing 3 via the screw 51. The length of the screw 51 may be set to a length that allows it to be threaded from the electronic board 9 (opening 10) into the screw hole 4 of the outdoor unit housing 3.

[0031] A sheet-like insulating material 38 is interposed between the electronic board 9 and the outdoor unit housing 3. A gap equivalent to the thickness of the insulating material 38 is maintained between the electronic board 9 and the outdoor unit housing 3. This makes it possible to significantly shorten the length of the screws 51 serving as the connectors 31, which are susceptible to the effects of external electromagnetic fields. As a result, it is possible to suppress the air conditioning outdoor unit 1 from being affected by external electromagnetic fields.

[0032] Furthermore, the electronic board 9 is fixed to the outdoor unit housing 3 by screws 51 having heads larger than the size of the screw holes 4. This allows the electronic board 9 to be fixed to the outdoor unit housing 3 without using any additional members. Although the opening 10 has a circular shape in the example described above, the opening shape may also be, for example, oval or rectangular.

[0033] Embodiment 3. An example of an air conditioner outdoor unit 1 as an electrical device according to embodiment 3 will now be described. As shown in Figures 8 and 9, a screw 61 and an annular conductor 63 are used as a connector 31 that electrically connects a metal plate 17 and an outdoor unit housing 3. The opening diameter of the annular conductor 63 is larger than the diameter of the screw 61. Note that Figure 8 shows an exploded view to more clearly illustrate the structure.

[0034] An opening 10 is formed in the board body 15 including the metal plate 17 as a first connected portion 33, through which the screw 61 is inserted. A screw hole 4 is formed in the outdoor unit housing 3, into which the screw 61 is threaded. A sheet-like insulating material 38 is interposed between the electronic board portion 9 and the outdoor unit housing 3. Note that the rest of the configuration is the same as the configuration of the air conditioning outdoor unit 1 shown in Figures 1 and 2, so the same members are designated by the same reference numerals, and descriptions thereof will not be repeated unless necessary.

[0035] As shown in Figure 8, the metal plate 17 is electrically connected to the outdoor unit housing 3 by inserting the screw 61 through the opening 10 formed in the electronic board portion 9 and the through hole formed in the insulating material 38, with the annular conductor portion 63 interposed between the head of the screw 61 and the metal plate 17, and then screwing the screw 61 into the screw hole 4 formed in the outdoor unit housing 3.

[0036] In the air conditioner outdoor unit 1 as the electrical device described above, the metal plate 17 arranged on the electronic board 9 is electrically connected to the outdoor unit housing 3 via the screw 61. As shown in Fig. 9, a gap equivalent to the thickness of the sheet-like insulating material 38 is maintained between the electronic board 9 and the outdoor unit housing 3. This allows the length of the screw 61 as the connector 31, which is susceptible to the influence of external electromagnetic fields, to be significantly shortened, as described above. As a result, the air conditioner outdoor unit 1 can be prevented from being affected by external electromagnetic fields.

[0037] Furthermore, in the air conditioner outdoor unit 1, an annular conductor portion 63 is interposed between the head of the screw 61 and the metal plate 17. This effectively increases the conduction area between the screw 61 and the metal plate 17. As a result, the metal plate 17 can be effectively grounded to the outdoor unit housing 3 (ground potential) via the screw 61, etc.

[0038] Fourth Embodiment An example of an air conditioner outdoor unit 1 as an electrical device according to a fourth embodiment will now be described. As shown in Figures 10 and 11 , a spacer conductor jig 71 having a screw 72 formed on one end and a screw 73 formed on the other end, and a nut 75 threaded onto the screw 72, are used as a connector 31 that electrically connects a metal plate 17 and an outdoor unit housing 3. A flange 74 is formed on the spacer conductor jig 71 as a spacing member. The diameter of the flange 74 is larger than the diameters of the screws 72 and 73. Note that Figure 10 shows an exploded view to more clearly illustrate the structure.

[0039] An opening 10 is formed in the board body 15 including the metal plate 17 as the first connected portion 33, through which the screw 72 is inserted. A screw hole 4 is formed in the outdoor unit housing 3, into which the screw 73 is threaded. A flange portion 74 is interposed between the electronic board portion 9 and the outdoor unit housing 3. Note that the rest of the configuration is the same as the configuration of the air conditioning outdoor unit 1 shown in Figures 1 and 2, so the same members are designated by the same reference numerals, and their description will not be repeated unless necessary.

[0040] As shown in Figure 10, the metal plate 17 is electrically connected to the outdoor unit housing 3 via a spacer conductor jig 71. In this case, the screws 73 of the spacer conductor jig 71 are threaded into the threaded holes 4, and the flanges 74 are brought into contact with the outdoor unit housing 3. In this state, the screws 72 of the spacer conductor jig 71 are inserted into the openings 10 of the electronic board 9. Nuts 75 are threaded onto the screws 72. In this way, the metal plate 17 is electrically connected to the outdoor unit housing 3.

[0041] In the air conditioner outdoor unit 1 as the electrical device described above, the metal plate 17 arranged on the electronic board 9 is electrically connected to the outdoor unit housing 3 via a spacer conductor jig 71. As shown in Fig. 11 , a gap corresponding to the thickness of the flange 74 is maintained between the electronic board 9 and the outdoor unit housing 3. The thickness of the flange 74 is set to a thickness that avoids unexpected risks, such as an electrical short circuit from parts other than the metal plate 17, between the electronic board 9 and the outdoor unit housing 3.

[0042] As a result, as already explained, the length of the spacer conductor jig 71 serving as the connector 31, which is susceptible to the effects of external electromagnetic fields, can be significantly shortened, thereby suppressing the air conditioning outdoor unit 1 from being affected by external electromagnetic fields.

[0043] The connector 31 has been described using the spacer conductor jig 71 having the screw 73 formed at the other end as an example. The spacer conductor jig 71 does not necessarily have to have the screw 73 formed thereon as long as it has a structure that allows the other end of the spacer conductor jig 71 to be fastened to the outdoor unit housing 3.

[0044] (Modification) In the air conditioner outdoor unit 1 according to each of the above-described embodiments, the electronic board 9 on which the noise filter 11 and the power conversion circuit 13 are formed has been described as an example. The electronic board 9 may be provided with a function to suppress surges caused by lightning. As shown in Fig. 12, the electronic board 9 is provided with a lightning arrester 12 (varistor or arrester) between the noise filter 11 and the power conversion circuit 13. The rest of the configuration is the same as the configuration of the air conditioner outdoor unit 1 shown in Figs. 1 and 2, so the same members are designated by the same reference numerals, and descriptions thereof will not be repeated unless necessary.

[0045] In the air conditioner outdoor unit 1 according to the modified example, a lightning arrester 12 is provided on the electronic board unit 9. This makes it possible to protect the electronic board unit 9 housed in the air conditioner outdoor unit 1 installed outdoors in the event of a lightning strike.

[0046] In the above-described embodiments, the electrical equipment is described by taking the air conditioner outdoor unit 1 as an example. The electrical equipment is not limited to the air conditioner outdoor unit 1, and the present invention can be applied to electrical equipment having a power converter such as an inverter circuit or a DC-DC converter circuit (Direct Current).

[0047] The air conditioner outdoor units described in each embodiment can be combined in various ways as needed. For example, the spacer conductor jig 71 described in the fourth embodiment may be used in place of the screw 61 described in the third embodiment.

[0048] The embodiments disclosed herein are examples and are not intended to be limiting. The scope of the present disclosure is defined by the scope of the claims, not the scope described above, and is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

[0049] The present disclosure is effectively applied to an electric device equipped with a power conversion circuit.

[0050] REFERENCE SIGNS LIST 1 Air conditioning outdoor unit, 3 Outdoor unit housing, 4 Screw hole, 5 Compressor, 7 Fan, 9 Electronic board section, 10 Opening, 11 Noise filter, 12 Lightning arrester, 13 Power conversion circuit, 15 Board body, 17 Metal plate, 19 Terminal block, 21 Metal member, 23 Electric wire, 25 Grounding wire, 27 Electric wire, 29 Cable, 31 Connector, 33 First connected part, 35 Second connected part, 37 Spacing member, 38 Insulating material, 41 Male connector, 42 Female connector, 43 Wiring member, 44 Crimp terminal, 45, 51, 61 Screw, 62 Annular conductive member, 71 Spacer conductor jig, 72, 73 Screw, 74 Flange portion, 75 Nut.

Claims

1. An electrical device having a power conversion circuit, comprising: a conductive housing; an electronic board section housed in the conductive housing and including the power conversion circuit and a noise filter; and a connector having a first end and a second end, electrically connecting the electronic board section and the conductive housing, wherein the electronic board section comprises: a board body; and a conductor plate arranged on the board body and electrically connected to the conductive housing, wherein the electronic board section has a first connected portion to which the first end of the connector is connected, and the conductive housing has a second connected portion to which the second end of the connector is connected, and the electronic board section is disposed so as to face the conductive housing with a spacing member interposed between the electronic board section and the conductive housing, an electrical device in which, when the first end of the connector is connected to the first connected portion, the first end is electrically connected to the conductor plate, and, when the second end of the connector is connected to the second connected portion, the second end is electrically connected to the conductive housing.

2. The electrical device of claim 1, wherein the connecting body includes a wiring member having a female connector disposed at the first end and a crimp terminal disposed at the second end, the first connected part includes a male connector that engages with the female connector, and the second connected part includes a first screw hole into which a first screw inserted into the crimp terminal screws.

3. An electrical device as described in claim 1, wherein the connecting body includes a second screw, the first connected portion includes a board opening through which the second screw is inserted, and the second connected portion includes a second screw hole into which the second screw screws.

4. An electrical device as described in claim 3, wherein the conductor plate is disposed on a surface of the substrate body opposite to a surface facing the conductive housing, and the connector includes an annular conductive member that is inserted through the second screw and contacts the conductor plate.

5. The electrical device according to claim 3 or 4, wherein a sheet-like insulating material is interposed between the substrate body and the conductive housing as the spacing member.

6. The electrical device of claim 1, wherein the connecting body includes: a conductor jig having a fourth screw formed at the first end and a fifth screw formed at the second end; a flange portion disposed between the first end and the second end of the conductor jig as the spacing member; and a nut screwed onto the fourth screw; the first connected portion includes a board opening through which the fourth screw is inserted; and the second connected portion includes a third screw hole into which the fifth screw is screwed.

7. An electrical device according to any one of claims 1 to 6, comprising: a terminal block housed in the conductive housing and through which wiring for supplying power from an external power source to the electronic board is relayed; and a conductive member electrically connected to the conductive housing and on which the terminal block is disposed, the wiring including a ground wire, and the ground wire electrically connected to the conductive member.

8. The electrical device according to any one of claims 1 to 7, wherein a lightning arrester is provided in the electronic board between the noise filter and the power conversion circuit.

9. The electrical device according to any one of claims 1 to 8, comprising: a compressor housed in the conductive housing and electrically connected to the power conversion circuit; and a fan housed in the conductive housing.

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