Patent ID: 12203666

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of an electrical component module disclosed in the present application will be described in detail with reference to the drawings. The electrical component module disclosed in the present application is not limited to the embodiments described below.FIGS.1to3,FIG.8, andFIG.9illustrate an outdoor unit100according to an embodiment of the present invention. The outdoor unit100has a housing110including: a front panel111; a service panel112on the right side of the front panel111; a right side panel113; a left side panel114; a top panel115; a back panel116, and a bottom panel117. Stands118are attached to the bottom panel117. The internal space of the housing110is divided by a partition plate119, in a left and right direction, into a heat exchange section110A and a machine section110B respectively provided behind the front panel111and the service panel112. The partition plate119is a part of a wall surface of the machine section110B. The heat exchange section110A accommodates the outdoor heat exchanger11and the blower fan11F described above. Furthermore, the machine section110B accommodates the refrigerant pipe30, the compressor12, the expansion valve14, the accumulator15, sub-accumulator15A, the four-way valve16, and the like described above. The internal space of the machine section110B can be viewed from the front side of the outdoor unit100when the service panel112is removed.

As illustrated inFIGS.4to9, electrical component module200includes: a fixed plate210that is disposed in the machine section110B to have the front surface facing the back surface of the service panel112; an upper frame220to which an upper portion of the fixed plate210serving as one end portion is attached, the upper frame220serving as a first frame that has an elongated shape; a lower frame230to which a lower portion of the fixed plate210serving as the other end portion is attached, the lower frame230serving as a second frame that has an elongated shape; an attachment metal fitting240with which the upper frame220is attached to the partition plate119; an attachment metal fitting250with which the lower frame230is attached to the partition plate119; a main board260on which the electronic components forming a part of the control circuit serving as a control unit as well as other electronic components are mounted; and a power board270on which the electronic components forming the remaining part of the control circuit and other electronic components, as well as a plurality of power devices274described later are mounted.

Thus, the printed circuit board of the electrical component module200is divided into the main board260and the power board270. The main board260serving as the printed circuit board is mounted on the fixed plate210to have a back surface260bdescribed later facing a front surface211aof the fixed plate210described later. The power board270serving as the printed circuit board is mounted on the fixed plate210to have a back surface270bdescribed later facing a back surface211bof the fixed plate210described later. The fixed plate210is arranged to have the front surface211afacing the direction toward the service panel112. The fixed plate210is arranged with the direction of connection between the upper part and the lower part of the fixed plate210being in parallel with the upward and downward direction of the machine section110B.

The electrical component module200further includes a cooler300that is attached to a part of a refrigerant pipe30L, with the refrigerant pipe30L sandwiched between the back surface211bof the fixed plate210and the cooler300. As described later, the cooler300is attached to the upper frame220and the lower frame230so as to bridge between the upper frame220and the lower frame230, with a U-shaped bent portion31of the refrigerant pipe30L attached to the cooler300.

The fixed plate210includes: a main body portion211having the front surface211aon which the main board260is mounted and the back surface211bon which the power board270is mounted; an upper horizontal piece212for reinforcement that is bent by 90 degrees from the upper end of the main body portion211toward the back surface211b; and an upper vertical piece213for attachment that is bent upward by 90 degrees from the rear edge of the upper horizontal piece212. The fixed plate210further includes: a lower horizontal piece214for reinforcement that is bent by 90 degrees from the lower end of the main body portion211toward the front surface211a; and a lower vertical piece215for attachment that is bent downward by 90 degrees from the front edge of the lower horizontal piece214. The lower vertical piece215has both ends provided with attachment portions215aprotruding downward.

The upper frame220includes: a vertical piece221screwed to the upper vertical piece213of the fixed plate210; an upper horizontal piece222for reinforcement that is bent backward by 90 degrees from the upper end of the vertical piece221; and an attachment piece223that is bent forward by 45 degrees from the left end of the vertical piece221. The upper end portion of the cooler300is attached to an end portion224of the upper frame220.

The lower frame230includes: a lower vertical piece231screwed to the lower vertical piece215of the fixed plate210; an upper horizontal piece232for reinforcement that is bent backward by 90 degrees from the upper end of the lower vertical piece231; an upper vertical piece233for reinforcement that is bent upward by 90 degrees from the back end of the upper horizontal piece232; and an attachment piece234that is bent forward by 45 degrees from the left end of the lower vertical piece231. Then, a terminal board400is attached to the front side of the lower vertical piece231. The lower end portion of the cooler300is attached to an end portion235of the lower frame230.

The cooler300includes: a heat sink310made of aluminum that is thermally coupled with the plurality of power devices274, which will be described later, mounted on a front surface270aof the power board270; the U-shaped bent portion31of the liquid side refrigerant pipe301fit in two grooves311that are formed in the heat sink310and have semicircular cross sections; and a cover320that is made of sheet metal and is used for fixing the U-shaped bent portion31on the heat sink310. In addition to the grooves311, the heat sink310includes: a thick plate portion312against which the power devices274are pressed for the thermal coupling; and cover attachment portions313and314formed on both sides of the thick plate portion312. The cover320includes: a holding portion321at the center with which the U-shaped bent portion31of the liquid side refrigerant pipe30L is pressed; a hook portion322bent from one end of the holding portion321; and an attachment portion323bend from the other end of the holding portion321to face the hook portion322.

On the front surface260aof the main board260, the electronic components forming a part of the control circuit and other electronic components are mounted as described above. Specifically, as illustrated inFIG.10, the components mounted on the front surface260aof the main board260include: an AC input current detection/temperature detection circuit261; an actuator drive circuit262that drives the expansion valve14and the four-way valve16; a display setting circuit263including an LED lamp263aserving as a display unit as well as a DIP switch263band a button switch263cserving as an operation unit, and the like; a main control IC264such as a microcomputer; an electromagnetic compatibility (EMC) filter circuit265for countering internal and external noise including a common mode choke coil265aand capacitors265b; a switching power circuit266including a switching transformer266aand a switching IC266b; an inrush current control circuit267; and a plurality of connectors268arranged in a peripheral portion. The reference numeral260bdenotes the back surface of the main board260. The main board260is formed in a rectangular shape and has an upper end260c, a lower end260d, a left end260e, and a right end260f. The main board260is mounted on the front surface211aof the main body portion211of the fixed plate210to have the back surface260bfacing the front surface211a.

On the front surface270aof the power board270, the electronic components forming the remaining part of the control circuit, including the plurality of power devices274described later, are mounted as described above. Specifically, as illustrated inFIG.11, the components mounted include: a diode bridge circuit271afor rectification; two insulated gate bipolar transistor (IGBT) elements271bhaving a reduced operation resistance achieved with a MOSFET provided in the gate part of a bipolar transistor; two fast recovery diode (FRD) elements271cfor high speed operation; two power factor correction (PFC) coils271dfor power factor correction; and two aluminum electrolytic capacitors271efor high power smoothing. The diode bridge circuit271a, the IGBT elements271b, the FRD elements271c, the PFC coils271d, the electrolytic capacitors271e, and the like form a converter circuit271that converts AC power supplied from the outside and outputs the resultant power. Furthermore, an intelligent power module (IPM) element272and an inverter control IC273are mounted to form an inverter circuit with a drive circuit and a self-protection function. The inverter circuit converts the DC power supplied from the converter circuit271into AC power and outputs the AC power. The reference numeral270bdenotes the back surface of the power board270. The power board270is formed in a rectangular shape and has an upper end270c, a lower end270d, a left end270e, and a right end270f. Each of the diode bridge circuit271a, the IGBT elements271b, the FRD elements271c, and the IPM element272is the power device274that produces a large amount of heat. These components are mounted in a vertical arrangement near the left end270eso as to be more effectively coolable by the cooler300. The power board270is mounted on the back surface211bto have the back surface270bfacing the back surface211bof the main body portion211of the fixed plate210. The cooler300faces and is in contact with portions of the plurality of power devices274.

Then, the size of the power board270in the upward and downward direction is set to correspond to the size of the plurality of power devices274in the vertically arrangement, and the PFC coils271d, the electrolytic capacitors271e, and the inverter control IC273, and the like are arranged to be within this size in the upward and downward direction. Thus, the vertical size of the power board270is set to be slightly larger than the upward and downward direction size of the plurality of power devices274in the vertical arrangement. The size of the main board260in the upward and downward direction is set to be substantially the same as the size of the power board270in the upward and downward direction. The AC input current detection/temperature detection circuit261, the actuator drive circuit262, the display setting circuit263, the main control IC264, the EMC filter circuit265, the switching power circuit266, the inrush current control circuit267, the connectors268, and the like are mounted to be within this size. The IGBT elements271bmay be replaced with a MOSFET.

The electronic components mounted on the main board260and the power board270described above are merely examples, and can be changed without departing from the spirit of the present invention. The electronic components mounted on the main board260are low voltage electronic components that operate at a low voltage, and the electronic components mounted on the power board270are high voltage electronic components that operate at a high voltage. The high voltage electronic components produce a larger amount of heat and noise compared with the low voltage electronic components.

For arranging the electrical component module200in the machine section110B of the outdoor unit100, first of all, the attachment metal fitting240having an inclined surface241and the attachment metal fitting250having an inclined surface251are mounted on the partition plate119in advance. Then, as illustrated inFIG.5, the attachment piece223of the upper frame220is screwed to the inclined surface241of the attachment metal fitting240, and the attachment piece234of the lower frame230is screwed to the inclined surface251of the attachment metal fitting250. As a result, the upper frame220and the lower frame230are attached to the partition plate119in a cantilevered manner, to extend along the lateral direction.

Next, as illustrated inFIG.6, the heat sink310of the cooler300is installed using screws B1and B2, so as to bridge between the end portion224of the vertical piece221of the upper frame220and the end portion235of the upper vertical piece233of the lower frame230. Furthermore, as illustrated inFIG.7, the U-shaped bent portion31of the refrigerant pipe30L is pressed into the grooves311of the heat sink310, the hook portion322of the cover320is engaged with one cover attachment portion313of the heat sink310, the attachment portion323is pressed against the other cover attachment portion314of the heat sink310, and the attachment portion323is fixed to the cover attachment portion314using screws B3and B4. This work is performed with the back panel116of the outdoor unit100removed. With the operation described above, the cooler300is arranged so as to bridge between the end portion224of the upper frame220and the end portion235of the lower frame230, with the thick plate portion312of the heat sink310facing the direction toward the service panel112.

The main board260is mounted on the front surface211aof the main body portion211of the fixed plate210, and the power board270is mounted on the back surface211b. Then, the fixed plate210on which the main board260and the power board270are mounted is attached using the screws B5and B6with the upper vertical piece213overlapped on the vertical piece221of the upper frame220and the lower vertical piece215overlapped on the lower vertical piece231of the lower frame230. The fixed plate210is tightly fixed because the attachment piece223of the upper frame220and the attachment piece234of the lower frame230are attached to the partition plate119respectively via the attachment metal fitting240and the attachment metal fitting250, and the other end224of the upper frame220and the other end235of the lower frame230are fixed to the U-shaped bent portion31of the liquid side refrigerant pipe30L via the cooler300. In addition, the plurality of power devices274of the power board270is pressed against the thick plate portion312of the heat sink310of the cooler300, for thermal coupling therebetween. Thus, when the air conditioner starts operating, the heat produced by the power devices274is cooled by the cooler300. If the thick plate portion312of the heat sink310is coated with thermal grease having high thermal conductivity, the thermal coupling can further be improved. After the electrical component module200has been attached to the machine section110B as described above, a plug to which required wiring is connected is connected to the connector268of the main board260of the electrical component module200, and another required wiring is connected to the terminal board400.

The electrical component module200described above has two printed circuit boards that are the main board260and the power board270, but may be configured to include only one printed circuit board.FIG.12is a perspective view of an electrical component module200according to a modification of the embodiment.

As illustrated inFIG.12, a single printed circuit board360is fixed on the front surface211aof the fixed plate210to have a front surface360afacing the direction toward the service panel112(seeFIG.8) and to have a back surface360bfacing the front surface211aof the fixed plate210. In the printed circuit board360, the printed circuit board360according to the modification is a single board in which the main board260having the front surface260aon which electronic components forming a part of the control circuit and the power board270having the front surface270aon which electronic components including the plurality of power devices274and forming the remaining part of the control circuit are collectively configured. The printed circuit board360is formed in a rectangular shape and has an upper end360c, a lower end360d, a left end360g, and a right end360f.

The plurality of power devices274is provided on at least one of the front surface360aand the hack surface360bof the printed circuit board360. When the power devices274are provided on the front surface360aof the printed circuit board360, the power devices274protrudes on the side of the back surface360bof the printed circuit board360through a through hole (not illustrated) of the printed circuit board360.

The fixed plate210is provided with openings216for thermally coupling the plurality of power devices274, mounted on the printed circuit board360, with the cooler300. The openings216are formed at positions that face the power devices274. The power devices274of the printed circuit board360attached to the fixed plate210are in contact with the thick plate portion312of the heat sink310of the cooler300through the openings216.

Instead of the openings216, a notched portion (not illustrated) through which the power devices274of the printed circuit board360pass may be formed in an outer circumference portion of the fixed plate210. The fixed plate210is not limited to the structure having the openings216and the notched portion. For example, the power devices274of the printed circuit board360may be arranged on the outer circumference side of the fixed plate210to be thermally coupled with the cooler300over the outer circumference portion of the fixed plate210.

As described above, the electrical component module200according to the present embodiment includes: the fixed plate210on which the control circuit is mounted, the fixed plate210being arranged to have the front surface211afacing the direction toward the service panel112; and the cooler300attached to a part of the refrigerant pipe301with the refrigerant pipe301sandwiched between the back surface211bof the fixed plate210and the cooler300. This allows maintenance work to be easily performed on the printed circuit board360(or the main board260and the power board270) of the control circuit without the need for removing the cooler300from the machine section110B when the maintenance work is performed on the printed circuit board360(or the main board260and the power board270) of the control circuit. The electrical component module200further includes: the upper frame220having an elongated shape with which the upper portion of the fixed plate210is attached to the machine section110B; and the lower frame230having an elongated shape with which the lower portion of the fixed plate210is attached to the machine section110B. The cooler300is attached to bridge between the upper frame220and the lower frame230. As described above, the upper frame220and the lower frame230are connected to each other via the fixed plate210and via the cooler300. Thus, the mechanical strength of a supporting structure for the main board260, the power board270, and the printed circuit board360supported by the fixed plate210, the upper frame220, and the lower frame230can be improved with a simple structure. More specifically, in the electrical component module200, the cooler300also serves as a part of the supporting structure for the main board260, the power board270, and the printed circuit board360, so that the supporting structure can be simplified.

By the way, when only a single printed circuit board360is used in the outdoor unit100(FIG.12), the low voltage electronic components are provided in the low voltage region and the high voltage electronic components are provided in the high voltage region, with the components arranged along the upward and downward direction of the single printed circuit board360. When the low voltage electronic components and the high voltage electronic components are thus arranged in series along the upward and downward direction of the printed circuit board360, the printed circuit board360needs to have a large size in the upward and downward direction. Thus, such a printed circuit board360is difficult to apply to an outdoor unit with a machine section not having much space in the upward and downward direction. In view of this, the printed circuit board360is preferably divided into two printed circuit boards (the main board260and the power board270) to be separately mounted on the front surface211aand the back surface211bof the fixed plate210. Meanwhile, if there is a difference between the main board260and the power board270in the upward and downward direction size, the effect of dividing the printed circuit board360into two boards is compromised.

In view of this, in the present embodiment, the main board260and the power board270in a back-to-back state are mounted on the fixed plate210via the fixed plate210attached to the machine section110B. Thus, the size of the main board260and the power board270in the upward and downward direction can be substantially reduced from the size of the printed circuit board in the upward and downward direction in the case where the main board260and the power board270are arranged in series in the upward and downward direction to be a single board. Thus, this configuration can be effectively applied to the outdoor unit including a housing without much space in the upward and downward direction.

In this configuration, the electronic components other than the power devices274are distributed between the main board260and the power board270with the upward and downward direction size of the power board270set to correspond to the size of the plurality of power devices274arranged in the upward and downward direction, and with the size of the main board260set to be the same as or substantially the same as the upward and downward direction size. Thus, the main board260and the power board270can have small sizes in the upward and downward direction.

Furthermore, the lower vertical piece231of the lower frame230protrudes toward the front surface beyond the fixed plate210due to the upper horizontal piece232, and the terminal board400is attached to the front surface231aof the lower vertical piece231. Thus, the terminal board400protrudes forward so as to be easily accessible, and a wide space SP can be provided to the back surface231bof the lower vertical piece231. Thus, the lower frame230does not interfere with a pipe and the like to be arranged in the space SP.

The plurality of power devices274mounted on the power board270is thermally coupled with the cooler300on the back surface211bside of the fixed plate210, and is simply pressed against the cooler300. Thus, by loosening the screws B5and B6, the fixed plate210, the main board260, and the power board270can be integrally removed from the front surface of the machine section110B without the cooler300hindering this operation, whereby maintenance work can be easily performed on the main board260and the power board270.

Furthermore, display setting circuit261including LED lamp263a, DIP switch263b, button switch263c, and the like and the plurality of connectors268are mounted on the front surface260aof the main board260. This enables operations such as checking the operation status of the air conditioner by checking the display status of the LED lamp263a, changing the setting contents by operating the DIP switch263b, the button switch263c, and the like, and switching the circuit connection by inserting or pulling out a plug to and from the connectors268to be easily performed, by simply removing the service panel112from the outdoor unit100.

REFERENCE SIGNS LIST

30L Liquid side refrigerant pipe31U-shaped bent portion100Outdoor unit110Housing110A Heat exchange section1108Machine section111Front panel112Service panel113Right side panel114Left side panel115Top panel116Back panel117Lower side panel118Stand119Partition plate200Electrical component module210Fixed plate211Main body portion211aFront surface211bBack surface212Upper horizontal piece213Upper vertical piece214Lower horizontal piece215Lower vertical piece216Opening220Upper frame221Vertical piece222Horizontal piece223Attachment piece230Lower frame231Lower vertical piece232Upper horizontal piece233Upper vertical piece234Attachment piece240Attachment metal fitting250Attachment metal fitting260Main board260aFront surface260bBack surface270Power board270aFront surface270bBack surface274Power device300Cooler310Heat sink320Cover360Printed circuit board400Terminal board