KR20080071083A - Electric compressor - Google Patents

Abstract

An electric compressor is provided to enhance cooling efficiency for electronic components of an inverter assembly by directly cooling an electric heating plate of the inverter assembly, which comes in contact with refrigerant through a cooling hole. An electric compressor comprises an electric motor, a motor room, an inverter assembly and an inverter accommodating room(101). The inverter assembly includes a substrate(112) having an electronic circuit, electronic components(114,116,124,125) connected to the substrate, and a base(110) of supporting the substrate. A housing(24) is interposed between the motor room and the inverter accommodating room. A through hole(130) is formed on the housing from the motor room to the inverter accommodation room, and has a first end connected to the base. The motor room and the inverter accommodation room are sealed around the through hole.

Description

Electric Compressor {ELECTRIC COMPRESSOR}

The present invention relates to an electric compressor, and more particularly, to an inverter for driving an electric motor.

BACKGROUND ART An electric compressor having a compression mechanism portion is known to have a configuration including an electric motor for driving the compression mechanism portion and an inverter for controlling and driving the electric motor. Such an electric compressor accommodates and fixes an inverter in an inverter storage chamber. Some electric compressors have a structure in which each member of the inverter cannot be detached, and is disclosed, for example, in JP-A-2004-197688.

However, in the inverter of the conventional electric compressor as shown in Unexamined-Japanese-Patent No. 2004-197688, there exists a problem that the cooling efficiency of the electronic component contained in an inverter, especially a switching element is comparatively low.

For this reason, when using the switching element with low heat resistance temperature, temperature protection is needed, for example, and a structure becomes complicated. In addition, in the case of using a switching element having a high heat resistance temperature, it leads to a high cost and a large size of the configuration.

The present invention has been made to solve such a problem, and an object of the present invention is to provide an electric compressor that can improve the cooling efficiency of electronic components of an inverter assembly.

In order to solve the above-mentioned problem, the electric compressor which concerns on this invention is formed in the compression mechanism part which inhales a fluid from a suction pressure area | region, the electric motor which drives a compression mechanism part, and a suction pressure area | region, and accommodates an electric motor. And an inverter assembly for controlling the rotational speed of the electric motor and converting the DC power into a multiphase AC power and supplying the electric motor to the electric motor. Is equipped with a board | substrate which has an electric circuit, the electronic component connected to the board | substrate, and the base which supports a board | substrate, and is detachably fixed in an inverter accommodating chamber, and the motor chamber and the inverter accommodating chamber have a housing interposed between them. In the adjacent electric compressor, a through hole is formed in the housing from the motor chamber to the inverter housing chamber, One end of the hole is in contact with the base, and the motor chamber and the inverter housing chamber are sealed around the through hole.

According to this electric compressor, the refrigerant | coolant in a suction pressure area | region, ie, the motor chamber on the low temperature side, flows into a through hole, and contacts a base through a housing. As a result, the base is directly cooled around the through hole. The base functions as a heat transfer plate and cools the electronic component.

The electronic component may include a switching element, and the through hole may be formed in the vicinity of the switching element.

By setting it as such a structure, a switching element can be cooled more efficiently. Among the elements constituting the electronic component, the switching element is a portion that tends to be hotter than other components. If the switching element can be cooled at a pin point in this manner, the entire electronic component can be cooled more efficiently.

The inverter assembly further includes a base for supporting the substrate, and the base may contact one end of the through hole.

By setting it as such a structure, the base which is a heat exchanger plate can also be used as a structure for sealing a motor room and an inverter storage chamber, and a structure is simplified.

According to the present invention, since the refrigerant in the suction pressure region is in contact with the heat transfer plate of the inverter assembly through the cooling hole and directly cools the heat transfer plate, the cooling efficiency of the electronic component of the inverter assembly can be improved.

According to the present invention, the switching element can be cooled more efficiently. Among the elements constituting the electronic component, the switching element is a portion that tends to be hotter than other components. If the switching element can be cooled at a pin point in this manner, the entire electronic component can be cooled more efficiently.

According to this invention, the base which is a heat exchanger plate can also be used as a structure for sealing a motor room and an inverter storage chamber, and a structure is simplified.

According to the present invention, since the refrigerant in the suction pressure region contacts the heat transfer plate of the inverter assembly through the cooling hole and directly cools the heat transfer plate, the cooling efficiency of the electronic component of the inverter assembly can be improved.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described based on attached drawing.

(Embodiment 1)

1 shows an electric compressor 10 according to Embodiment 1 of the present invention.

The electric compressor 10 includes a first housing 24 and a second housing 25. The first housing 24 and the second housing 25 are fixed to each other by bolts 16. The first housing 24 has a bottomed cylindrical shape that includes a cylindrical portion 24f and a bottom portion 24g, and a cylindrical shaft support portion 24h is formed in the bottom portion 24g.

In addition, in FIG. 1, the right side of a figure, ie, the 2nd housing 25 side is front, and the left side of the figure, ie, the bottom part 24g side of the 1st housing 24 is defined backward.

The electric compressor 10 includes a fixed scroll 11, a swing scroll 12, and a compression chamber 13 formed by the fixed scroll 11 and the swing scroll 12. The fixed scroll 11 is provided with the disk-shaped fixed base 11a, the spiral fixed wrap 11b standing up from the fixed base 11a, and the fixed wrap outermost wall 11c. The discharge port 47 is formed in the center of the fixed base 11a.

In the electric compressor 10, the compression mechanism portion is composed of a fixed scroll 11, a swinging scroll 12, and a compression chamber 13, and sucks a fluid from a suction pressure region, compresses it and discharges it. Discharge into the pressure area. Here, the suction pressure region is a region through which fluid sucked from the outside of the electric compressor 10 flows into the compression chamber 13, and the discharge pressure region is compressed in the compression chamber 13. It is an area passing through the fluid until it flows out of the electric compressor 10.

The swinging scroll 12 is composed of a disk-shaped swing base 12a and a swirl-shaped swing wrap 12b standing up from the swing base 12a, and at the rear side center of the swing base 12a, A bottomed cylindrical holding portion 12c holding the ball bearing 17 is formed.

In addition, the electric compressor 10 includes a drive crank mechanism 19 for causing the swing scroll 12 to perform swing motion (orbital motion), and a pin 20 for preventing rotation of the swing scroll 12. . The pin 20 is attached to the axial support member 15 and is formed to fit loosely in the annular recess 12d of the revolving scroll 12.

The drive crank mechanism 19 is attached to the holding part 12c, the crank pin 22a of the drive shaft 22, and the ball bearing 17 which carries this crank pin 22a through the bush 18. It is composed by.

The drive shaft 22 penetrates the center of the electric motor 26. The electric motor 26 drives the compression mechanism part, the stator in which the drive shaft 22, the rotor 28 fitted to this drive shaft 22, and the outer peripheral side were wound, and the coil 29 was wound up. It is a three-phase synchronous motor provided with (30).

In the outer surface close to the rear of the first housing 24, a part of the first housing 24 is recessed to form an inverter storage chamber 101. The electric compressor 10 includes an inverter assembly 100 accommodated in the inverter storage chamber 101. In addition, the detailed structure of the inverter assembly 100 is mentioned later with reference to FIG. 2, and in FIG. 1, only the heat-transfer plate 110 is shown for simplicity and clarity.

The inverter assembly 100 is electrically connected to the electric motor 26 via an airtight terminal 122 (described later with reference to FIG. 2) formed in the first housing 24.

The inverter assembly 100 converts the DC power supplied from the outside into polyphase AC power, supplies it to the electric motor 26, and controls the rotation speed of the electric motor 26.

Moreover, the cover 150 is attached to the 1st housing 24 so that the inverter assembly 100 may be covered, and this cover 150 isolates the inverter storage chamber 101 from the exterior. Here, the cover 150 constitutes the outer wall of the electric compressor 10. That is, the cover 150, the first housing 24, and the second housing 25 decouple the inside of the electric compressor 10 from the outside. In addition, the inverter storage chamber 101 is formed with the cover 150 and the first housing 24 as outer walls.

In addition, when the electric compressor 10 is used, in FIG. 1, it arrange | positions so that the direction which looked at the inverter assembly 100 from the drive shaft 22 may become upward. In other words, the inverter assembly 100 is disposed above the first housing 24.

The stage on the side of the drive crank mechanism 19 of the drive shaft 22 is supported by the shaft support member 15 via the ball bearing 22e, and the rear end thereof is the first housing 24 via the ball bearing 22f. Is supported by the shaft support portion 24h. Further, a seal 22g is formed on the rear side of the ball bearing 22e and seals between the drive shaft 22 and the shaft support member 15.

The fluid which is a refrigerant flows through the space covered by the 1st housing 24 mentioned above and the 2nd housing 25. In this space, the portion partitioned by the first housing 24 and the shaft support member 15 is the motor chamber 27, and the first housing 24, the second housing 25, and the shaft support member. The part partitioned by 15 is the crank chamber 21. The motor chamber 27 and the crank chamber 21 communicate with each other by a passage not shown.

1 and 2, the motor chamber 27 and the inverter accommodating chamber 101 are adjacent to each other with the first housing 24 therebetween.

On the side opposite to the compression chamber 13 with respect to the discharge port 47, a discharge chamber 32 partitioned by the fixed scroll 11 and the second housing 25 is formed, and the refrigerant compressed in the compression chamber 13 It discharges to the discharge chamber 32 via the discharge port 47. A reed valve 34 and a retainer 36 are formed in the discharge chamber 32 to prevent the backflow of the refrigerant, that is, the generation of the flow from the discharge chamber 32 toward the discharge port 47. The discharge chamber 32 also has an outer opening 32a in communication with the outside. The inside and the outside of the electric compressor 10 communicate with each other by the outer opening 32a.

In the electric compressor 10 comprised as mentioned above, a refrigerant | coolant flows in into the motor chamber 27 from the exterior through the suction port which is not shown in figure. In addition, the coolant flows from the motor chamber 27 into the crank chamber 21 and the compression chamber 13 in communication with the crank chamber through a suction passage not shown. In the compression chamber 13, the refrigerant is compressed by the turning of the swinging scroll 12 accompanied by the rotation of the drive shaft 22, flows into the discharge chamber 32 from the discharge port 47, and again, the external opening 32a. It is discharged to outside through).

In FIG. 2, the inverter assembly 100 which concerns on Embodiment 1 of this invention, and its peripheral structure are shown.

FIG. 2 is a partial cross-sectional view taken along line II-II of FIG. 1.

The cover 150 and the first housing 24 sandwich the gasket 120, whereby the inverter housing chamber 101 is isolated from the outside. The gasket 120 is a plate-shaped member composed of a core which is an iron plate and a rubber material surrounding the core.

The inverter assembly 100 includes a substrate 112 having an electric circuit and a heat transfer plate 110 that is a base that supports the substrate 112. The heat exchanger plate 110 is made of a material having a relatively high thermal conductivity, for example, aluminum, and mediates conduction of heat between the motor chamber 27 and the inverter accommodation chamber 101. The board | substrate 112 is fixed to the heat exchanger plate 110 with the screw 128.

The cover 150, the heat transfer plate 110, and the first housing 24 are tightened and fixed together by the screws 118, and the heat transfer plate 110 is mounted in close contact with the first housing 24. In addition, since the screw 118 is formed in a position different from the cross section of FIG. 2, the part to be fastened together is not shown in FIG. In FIG. 2, only the head portion of the screw 118 is shown for explanation.

In addition, the inverter assembly 100 includes a capacitor 114, a coil 116, an airtight terminal 122, an IGBT (Insulated Gate Bipolar Transistor, an insulated gate bipolar transistor) 124 and 125 as switching elements, And varistors (not shown).

The capacitor 114 is an electrolytic capacitor, for example, and has a lead 114a. The lead 114a is soldered to the substrate 112 to electrically connect the capacitor 114 with the electrical circuit of the substrate 112. The capacitor 114 is fixed to the substrate 112 by the lead 114a and solder (not shown) around the lead 114a, and is further bonded to the heat transfer plate 110 by a resin adhesive 114b. It is fixed.

The coil 116 has a lead 116a, which is soldered to the substrate 112 to electrically connect the coil 116 to the electrical circuit of the substrate 112. The coil 116 is fixed to the substrate 112 by the leads 116a and solder (not shown) around the leads 116a, and the coils 116 are formed on the heat transfer plate (111b) by the resin adhesive 116b. It is attached to and fixed to 110).

The IGBTs 124 and 125 have leads 124a and 125a, respectively, which are soldered to the substrate 112 to connect the IGBTs 124 and 125 to the electrical circuitry of the substrate 112. Connect with The IGBTs 124 and 125 are fixed to the heat transfer plate 110 by screws 126 and 127, respectively.

The hermetic terminal 122 has a lead 122a, and the lead 122a is soldered to the substrate 112 to electrically connect the hermetic terminal 122 with the electric circuit of the substrate 112. The airtight terminal 122 is fixed to the heat transfer plate 110. In addition, although not shown in figure, the airtight terminal 122 electrically connects the inverter assembly 100 and the electric motor 26 (refer FIG. 1) in the 1st housing 24, and the inverter storage chamber 101 and The motor chamber 27 which is a space where the electric motor 26 is accommodated is hermetically enclosed.

In this way, the substrate 112, the condenser 114, and the coil 116 are supported by the heat transfer plate 110, and the inverter assembly 100 is assembled. As described above, the heat transfer plate 110 is fixed to the first housing 24 by screws 118, whereby the inverter assembly 100 is fixed to the first housing 24. This fixing is detachable screwed together by the screw 118.

Between the first housing 24 and the stator 30 (see FIG. 1), a coolant passage including at least a part of the motor chamber 27 is formed, and the coolant flows through the coolant. This refrigerant cools the heat transfer plate 110 through the first housing 24, thereby cooling the inverter assembly 100. In addition, the coolant cools the electric motor 26 through the stator 30.

This refrigerant passage is a low pressure side passage of the electric compressor 10. That is, the motor chamber 27 is formed in the suction pressure region of the electric compressor 10.

In the first housing 24, a cooling hole 130 directed from the motor chamber 27 toward the inverter housing chamber 101 is formed just below the IGBT 125. The cooling hole 130 is a through hole penetrating through the first housing 24, and the upper opening 130a is in contact with the heat transfer plate 110, whereby the heat transfer plate 110 comes into contact with the refrigerant in the suction pressure region. Although the shape of the cooling hole 130 is a hollow cylindrical shape, for example, this may be another shape.

Around the cooling hole 130, a seal structure for sealing the motor chamber 27 and the inverter accommodating chamber 101 is formed. In the example of FIG. 2, the O ring groove 130b is formed around the upper end opening 130a of the cooling hole 130, and the O ring 130c is disposed therein as a sealing member. The O-ring 130c is sandwiched by the first housing 24 and the heat transfer plate 110 to enclose the motor chamber 27 and the inverter accommodating chamber 101 around the cooling hole 130.

When assembling the electric compressor 10, the inverter assembly 100 is first assembled integrally. This may be done in any order, but for example, each electronic component is first mounted on the heat transfer plate 110, and then the substrate 112 is fixed to the heat transfer plate 110 by screws 128, and each electronic component is fixed. It is connected to the substrate 112.

After the inverter assembly 100 is assembled, it is mounted on the electric compressor 10. This is carried out by tightening and fixing the cover 150, the heat transfer plate 110, and the first housing 24 together by the screws 118.

In addition, since the sealing of the gel in the inverter storage chamber 101 is not performed here as mentioned above, the heat exchanger plate 110 is released from the 1st housing 24 by removing the screw 118, and an inverter The assembly 100 can be removed. That is, the integrated inverter assembly 100 is a cartridge type and is the structure which can be attached and detached in the electric compressor 10. As shown in FIG.

According to the electric compressor 10 comprised as mentioned above, the suction plate of the electric compressor 10, ie, the low temperature side refrigerant | coolant, is transferred from the motor chamber 27 through the cooling hole 130 at the upper end 130a of the heat exchanger plate ( 110). For this reason, the heat exchanger plate 110 is cooled directly in the periphery of the cooling hole 130. Here, since the cooling hole 130 is formed just below the IGBT 125, the refrigerant in the cooling hole 130 cools the IGBT 125 efficiently through the heat transfer plate 110. In this way, the electric compressor 10 can improve the cooling property of the IGBT 125 and the inverter assembly 100 including the same.

In addition, since the cooling efficiency is improved, the IGBT 125 can be kept at a lower temperature, and therefore, the heat resistance temperature required for the IGBT 125 can be lowered. For this reason, a smaller or lower cost switching element can be employed.

In addition, even when a switching element having a low heat resistance temperature is used, since the temperature protection becomes unnecessary, the inverter assembly 100 can be used in a wider operating area, that is, in a more various operating state.

In addition, since the refrigerant cools the heat transfer plate 110 directly without passing through the first housing 24, the cooling efficiency can be improved as compared with the configuration in which the refrigerant is indirectly cooled through the first housing 24.

In addition, since the inverter compressor 100 is detachable without encapsulating the gel in the inverter housing chamber 101 in the electric compressor 10, as compared with the structure in which the inverter assembly cannot be detached as in the related art, Maintenance is easy. In this way, the cooling efficiency can be improved as described above while facilitating maintenance.

In the conventional configuration, a fin or the like is formed to cool the inverter. However, in such a configuration, the shape of the mold for forming the fin and the like becomes complicated, and maintenance of the mold is difficult. In the electric compressor 10 which concerns on this embodiment, since the cooling hole 130 can be formed by forming a through-hole in the 1st housing 24, the mold of a comparatively simple shape can be used, and the maintenance is It becomes easier.

In Embodiment 1 mentioned above, in the example of FIG. 2, although the position of the cooling hole 130 is just under the IGBT 125, this may not be just below, for example, below the IGBT 125, or It may be nearby. In addition, as long as the efficiency which cools the IGBT 125 improves, it may be formed anywhere.

In addition, the cooling hole 130 may not cool the IGBT 125, and may cool at least one of electronic components, for example, the condenser 114 or the coil 116. In this case, the cooling hole 130 may be formed just below the condenser 114 or the coil 116, in the vicinity, or at the position where the efficiency of cooling them is improved. Also in such a structure, the inverter assembly 100 containing an electronic component can be cooled efficiently similarly to the structure shown in FIG.

In addition, in the example of FIG. 2, although only one cooling hole 130 is formed with respect to the IGBT 125, the cooling hole 130 may be formed with respect to several element. For example, one cooling hole may be formed in each of the IGBTs 124 and 125, and one cooling hole may be formed in each of the other electronic components.

In addition, a plurality of cooling holes 130 may be formed in one electronic component.

Although the electric compressor 10 is illustrated as being a scroll type, it may be of the other type as long as it is provided with the compression mechanism part which compresses a fluid.

 BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the structure of the electric compressor which concerns on Embodiment 1 of this invention.

FIG. 2 is a diagram illustrating a configuration of an inverter assembly included in the electric compressor of FIG. 1 and the surroundings thereof. FIG.

※ Explanation of code for main part of drawing ※

24: first housing (housing)

26: electric motor

100: inverter assembly

101: inverter storage room

110: heat transfer plate (base)

112: substrate

114 capacitors (electronic components)

116: coils (electronic components)

124 and 125: IGBTs (electronic components, switching elements)

130: cooling hole (through hole)

130a: top opening (one end of the through hole)

130c: O ring

Claims (3)

A compression mechanism portion for sucking fluid from the suction pressure region; An electric motor 26 for driving the compression mechanism part; A motor chamber 27 formed in the suction pressure region and accommodating the electric motor 26;  An inverter assembly 100 which converts DC power into polyphase AC power and supplies the same to the electric motor 26, and controls the rotation speed of the electric motor 26; An inverter accommodating chamber (101) for accommodating the inverter assembly (100), The inverter assembly 100 includes a substrate 112 having an electrical circuit, electronic components 114, 116, 124, and 125 connected to the substrate 112, and a base 110 supporting the substrate 112. ) And is detachably fixed to the inverter storage chamber (101), The motor chamber 27 and the inverter accommodating chamber 101 are adjacent to each other with the housing 24 interposed therebetween. In the housing 24, a through hole 130 is formed from the motor chamber 27 toward the inverter accommodation chamber 101, One end 130a of the through hole 130 is in contact with the base 110, The motor compressor (27) and the inverter housing chamber (101) are sealed around the through hole (130). The method of claim 1, The said compressor of the said motor chamber (27) and the said inverter accommodation chamber (101) uses the O-ring (130c), The electric compressor characterized by the above-mentioned. The method according to claim 1 or 2, The electronic component 114, 116, 124, 125 includes a switching element 124, 125, and the through hole 130 is formed in the vicinity of the switching element 124, 125. .

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