JP2002188573A - Motor-driven refrigerating cycle device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor-driven refrigerating cycle device capable of effectively cooling an inverter part, in particular, a smooth capacitor even with a simple and compact structure. SOLUTION: Though the inverter part 5 is fixed on a motor housing 4 to shorten the wiring and to miniaturize the device, the smooth capacitor 55 can be effectively cooled by a low pressure refrigerant flowing in a slot 511 of a base plate 51 by fixing a case 551 of the smooth capacitor 55 to the base plate 51 for mounting circuit parts of the inverter part 5, through a high thermal conductive member 52, whereby the smooth capacitor 55 can be prevented from being unnecessarily enlarged and lowering its electric resistance, the reliability is improved, and the device is miniaturized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an electric refrigeration cycle apparatus.

[0002]

2. Description of the Related Art In a refrigeration cycle apparatus using an electric compressor in which a compressor section is driven by an electric motor section, an inverter apparatus is used to drive an AC motor with a DC power supply. This inverter device includes an inverter circuit having upper arm elements and lower arm elements corresponding to the number of phases of an AC motor, and a smoothing capacitor for smoothing a DC pulsating voltage of the inverter circuit.

Further, in a refrigeration cycle apparatus using an electric compressor, a technique for fixing an inverter unit for controlling the driving of the electric motor unit to an outer surface of a motor housing (hereinafter, also referred to as an inverter-integrated electric compressor) is known. There is also known a technique of cooling a motor of an electric compressor with a refrigerant (also referred to as an electric motor-cooled cooling electric compressor).

[0004]

In a refrigeration cycle apparatus using the above-described electric compressor, it has been an important issue to prevent overheating of the smoothing capacitor together with the semiconductor element of the inverter section. Conventionally, a large-capacity electrolytic capacitor is used as the smoothing capacitor. However, the use temperature of the electrolytic capacitor is much lower than that of a film capacitor in terms of prevention of boiling of the electrolytic solution. In order to prevent overheating of the smoothing capacitor, it is conceivable to increase the size of the smoothing capacitor and reduce its internal electrical resistance. is not.

In particular, when the structure is simplified by attaching an inverter section to the motor housing of the electric compressor, the above-mentioned problem becomes more serious because the temperature of the motor housing is high. As described above, it is conceivable to introduce a refrigerant into the sealed motor housing to cool the motor housing, and to absorb the heat generated by the inverter unit by the motor housing having a low temperature. The refrigerant absorbs a large amount of heat generated by the motor, which causes a problem of a large increase in the amount of compression work. When high-pressure refrigerant is introduced, the high-pressure refrigerant has a high temperature, which is sufficient for cooling the motor. However, it is not suitable for cooling a smoothing condenser that needs to be operated at a significantly lower temperature.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an electric refrigeration cycle apparatus capable of excellently cooling an inverter unit, particularly a smoothing condenser.

[0007]

According to a first aspect of the present invention, there is provided an electric refrigeration cycle apparatus comprising: a compressor part forming a part of a refrigeration cycle apparatus; and a motor part driving the compressor part. An electric motor comprising: an electric compressor having a compressor housing axially coupled thereto; and an inverter unit having a semiconductor element for controlling the motor unit and a smoothing capacitor for reducing DC voltage pulsation and fixed to the motor housing. In the refrigeration cycle apparatus, the inverter unit has a base plate fixed to the motor housing and a case of the semiconductor element and the smoothing capacitor is fixed directly or through a good heat conducting member, and the base plate has a low-pressure refrigerant. It is characterized by being cooled by the flowing low pressure refrigerant passage for cooling the base.

According to the first aspect of the invention having the above structure, the case of the smoothing capacitor is directly or in good heat even though the inverter is fixed to the motor housing in order to shorten the wiring and downsize the device. Since it is fixed to the base plate for mounting the circuit components of the inverter unit through the conductive member, the smoothing capacitor can be satisfactorily cooled by the low-pressure refrigerant in the low-pressure refrigerant passage through the base plate. As a result, there is no need to unnecessarily increase the size of the smoothing capacitor to reduce its electrical resistance, and it is possible to achieve improvement in reliability and downsizing of the device.

According to a second aspect of the present invention, in the electric refrigeration cycle apparatus according to the first aspect, the low-pressure refrigerant for cooling the base further includes a contact plate that contacts a main surface of the base plate on the motor housing side. The passage is formed of a long groove recessed in at least one of the contact plate and the base plate.

In this way, it is possible to suppress the waste of extending or adding pipes for cooling the base plate, and it is also possible to reduce the thermal resistance between the low-pressure refrigerant and the base plate.

According to a third aspect of the present invention, in the electric refrigeration cycle apparatus according to the second aspect, the base plate and the contact plate are further extended until the base plate and the contact plate come into contact with a peripheral wall of the compressor housing. And the abutting plate has a compressor-side opening that connects the low-pressure refrigerant suction port of the compressor housing and the other end of the long groove in the direction of the fastening. It comes into contact with the peripheral wall of the compressor housing.

With this configuration, it is not necessary to add a low-pressure refrigerant pipe for cooling the base plate, and when the base plate is fastened to the motor housing or the compressor housing to fix the inverter section to the electric compressor, it is not necessary. The contact plate can also be fastened at the same time, the long groove can be sealed, and the assembling operation can be simplified.

According to a fourth aspect of the present invention, in the electric refrigeration cycle apparatus according to the second or third aspect, the contact plate abuts on a pedestal protruding from a peripheral wall of the motor housing. Further, it is possible to increase the thermal resistance between the contact plate and the motor housing to prevent the low-pressure refrigerant in the low-pressure refrigerant passage from being heated by the motor housing.

This construction is the same as providing the pedestal on the contact plate side. However, since the motor housing is usually formed by die-casting, this pedestal can also be formed in the same process. The contact plate can be manufactured by, for example, simple flat plate punching, and the total manufacturing process can be simplified.

According to a fifth aspect of the present invention, in the electric refrigeration cycle apparatus according to the second or third aspect, the contact plate further contacts the motor housing via a heat insulating plate having thermal insulation.

Since this kind of heat insulating plate is made of a non-metallic material, it also has an effect of suppressing vibration transmission, can effectively block the heat of the motor housing, and also alleviates the vibration from the shut-off electric compressor to the inverter at the same time. be able to.

According to a sixth aspect of the present invention, there is provided an electric refrigeration cycle apparatus having a compressor section forming a part of the refrigeration cycle apparatus and an electric motor section for driving the compressor section. A motor-driven refrigerating cycle device comprising an electric compressor coupled in a direction, and an inverter unit having a semiconductor element for controlling the motor unit and a smoothing capacitor for reducing DC voltage pulsation, and an inverter unit fixed to the motor housing. The inverter unit has a base plate that abuts on the compressor housing and to which the case of the semiconductor element and the smoothing capacitor is fixed directly or through a good heat conducting member.

According to this structure, the low-pressure refrigerant has a low-density refrigerant chamber whose volume is inevitably large due to its low density, and is cooled well by the low-pressure refrigerant. The base plate of the inverter unit is fixed to the housing, and the case of the smoothing capacitor is fixed directly to this base plate or through a good heat conducting member, so that the smoothing capacitor can be cooled well, the reliability of the smoothing capacitor can be improved and the compactness can be improved. Can be realized with a simple configuration.

According to a seventh aspect of the present invention, there is provided an electric refrigeration cycle apparatus having a compressor part forming a part of the refrigeration cycle apparatus and an electric motor part for driving the compressor part. An electric refrigeration cycle apparatus comprising: an electric compressor coupled in a direction; and an inverter unit provided with the semiconductor element for controlling the electric motor unit and a smoothing capacitor for reducing DC voltage pulsation and separately provided from the electric compressor. , The inverter section has a base plate to which the case of the semiconductor element and the smoothing capacitor is fixed directly or through a good heat conducting member, and the base plate also serves as a low-pressure refrigerant pipe.

That is, according to the present configuration, the low-pressure refrigerant pipe is partially cooled by the low-pressure refrigerant through the base plate while avoiding the addition of the low-pressure refrigerant pipe by replacing a part of the low-pressure refrigerant pipe with the base plate. It is possible to improve the performance and make the system compact with a simple configuration.

According to an eighth aspect of the present invention, in the refrigeration cycle apparatus according to the seventh aspect, the low-pressure refrigerant for cooling the base further comprises a contact plate that is in contact with a main surface of the base plate on the side opposite to the circuit mounting surface. The passage is formed of a long groove recessed in at least one of the contact plate and the base plate. With this configuration, the same operation and effect as those of the second aspect can be obtained.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the electric refrigeration cycle apparatus of the present invention will be described with reference to the following embodiments.

[0023]

Embodiment 1 One embodiment of an electric refrigeration cycle apparatus of the present invention applied to a vehicle air conditioner will be described below with reference to the drawings.

FIG. 1 is a schematic axial partial sectional view of the electric compressor, and FIG. 2 is a plan view of a base plate. In addition, since the refrigerant circuit itself other than the electric compressor integrated with the inverter is well known, the illustration and the description are omitted. (Overall configuration) 1 is a compressor part forming a part of a refrigeration cycle device for vehicle air conditioning, 2 is a motor part driving the compressor part 1, 3 is a compressor housing forming an outer shell of the compressor part, 4
Reference numeral denotes a motor housing forming an outer shell of the motor unit 2, 5 denotes an inverter unit for driving and controlling the motor unit 2 formed of a three-phase synchronous motor, 6 denotes a contact plate, 7 denotes packing (good heat conducting member in the present invention), 8 Is an O-ring and 9 is a flanged resin sleeve.

The housings 3 and 4 are coaxially connected to each other by a through bolt (not shown) adjacent to the rotating shaft (not shown) in the axial direction, so that the rotating shaft of the motor unit 2 drives the rotating shaft of the compressor unit 1. As a whole, it constitutes the electric compressor referred to in the present invention. Reference numeral 31 denotes a low-pressure refrigerant chamber in the compressor housing 3.

The inverter unit 5 includes a base plate 51,
Circuit accommodation room 5 formed by an outer shell composed of cover 52
3 and a three-phase inverter circuit 5
4, a smoothing capacitor 55, a wiring member (not shown) for connecting them, and other small circuit components (not shown).

The base plate 51 is made of aluminum, and is mounted on the flat upper surfaces of the compressor housing 3 and the motor housing 4 by bolts (not shown).
Are fastened. At this time, the O-ring 8 seals a long groove 511 described later, and the packing 7 seals a through hole 61 described later.

On the main surface of the base plate 51 on the side of the electric compressor, a long groove (low pressure refrigerant passage for cooling the base) 511 horizontally provided in a U-shape and a low pressure refrigerant inlet 512 communicating with one end of the long groove 511 are provided. Is formed. Low pressure refrigerant inlet 51
2 is supplied with a low-pressure refrigerant from an evaporator (not shown) through an external pipe (not shown) connected to a pipe connecting tubular portion 513 protruding from the upper surface of the base plate 51. The long groove 511 extends just below a three-phase inverter circuit 54 of the inverter unit 5 described later.

The cover 52 is an aluminum box with a bottom and is fixed on the base plate 51 by bolts (not shown).

The three-phase inverter circuit 54 includes u, v, w,
It has a well-known circuit configuration in which a phase inverter circuit in which an upper arm element and a lower arm element for three phases are connected in series is connected in parallel and a DC voltage is applied from a battery (not shown).
A bus bar (only one is shown in FIG. 1) 56 that forms an AC output terminal of the three inverter circuits of the v and w phases protrudes in the axial direction. Upper arm element and lower arm element are each IG
Although the BT and the flywheel diode are connected in anti-parallel, further description is omitted because it is well known. In this embodiment, the three-phase inverter circuit 54 is used to simplify the description.
Has a single resin-molded semiconductor module configuration, but of course, various variations are possible. The three-phase inverter circuit 54 is in close contact with and fixed to the circuit mounting surface 540 of the base plate 51, and a smoothing capacitor 55 is mounted and fixed thereon, thereby forming a two-story structure as a whole.

The smoothing capacitor 55 is composed of an electrolytic capacitor housed in an aluminum case 551 and is connected in parallel with the three-phase inverter circuit 54 to absorb a high-frequency switching voltage applied from the three-phase inverter circuit 54 to a battery (not shown). I do. The case 551 of the smoothing capacitor 55 includes a cover (good heat conductive member referred to in the present invention) 52.
Is in close contact with the bottom surface (located at the upper side in FIG. 1) through grease having good thermal conductivity.

This embodiment is not characterized by the arrangement and shape of the three-phase inverter circuit 54 and the smoothing capacitor 55. For example, the smoothing capacitor 55 is closely attached to the base plate 51 and fixed, or a special frame is used. It may be arranged on the three-phase inverter circuit 54 at a distance from the three-phase inverter circuit 54.

The contact plate 6 is made of a thin aluminum plate, and has a through hole 61 communicating with the other end of the long groove 511 of the base plate 51. The through hole 61 communicates with the low pressure refrigerant chamber 31 of the compressor housing 3 through the through hole 71 of the packing 7 and the refrigerant suction hole 32 of the compressor housing 3.

The flanged resin sleeve 9 is an electrically insulating resin member and includes a base plate 51, a contact plate 6,
The packing 7 is press-fitted through the motor housing 4. The sleeve 9 has a flat cylindrical shape, and has three through holes (not shown) inside.

A three-phase synchronous motor (not shown) is housed in the motor housing 4 and connected to the ends of three armature windings of the three-phase synchronous motor, and each output terminal (only one in FIG. 41) individually penetrate the through holes of the resin sleeve 9 with a flange, and
3 protrudes. A male screw surface is formed at the tip of each output terminal 41, and a bus bar (only one is shown in FIG. 1) 56 protruding laterally from the three-phase inverter circuit 54 is individually connected to each output terminal 41 by the nut 10. Has been concluded.

(Assembling Order) Next, the assembling order of the inverter-integrated electric compressor will be described below.

Circuit components such as a three-phase inverter circuit 54 and a smoothing capacitor 55 are mounted, and a base plate 51 on which necessary wiring is completed is fastened to the compressor housing 3 and the motor housing 4 through the contact plate 6, and a bus bar 56 is output. What is necessary is just to fasten to the terminal 41 and fasten the cover 52 to the base plate 51.

(Operation) The high-pressure refrigerant discharged from the compressor unit 1 cools the electric motor unit 2 and is sent from the motor housing 4 to a condenser (not shown). A cylindrical portion 513, a long groove 511, through holes 61, 71, 32 are provided from an evaporator (not shown).
Through the compressor housing 3. The three-phase inverter circuit 54 has a long groove 51 through the base plate 51.
1 is cooled by the low-pressure refrigerant in the
Is a long groove 51 through the cover 52 and the base plate 51.
1 is cooled by the low-pressure refrigerant.

(Modification 1) The smoothing capacitor 55 can be cooled by the base plate 51 through a mount made of a good heat conducting member.

(Modification 2) The sleeve 9 may be fixed to the three-phase inverter circuit 54 or the base plate 51, and the bus bar 52 may be suspended in the motor housing 4 through the sleeve 9. In this case, the three-phase output terminal of the electric motor unit 2 and the bus bar 56 are connected in the motor housing 4.

(Modification 3) The contact plate 6 may be made of a material having poor thermal conductivity such as a rubber sheet or a resin plate. When the rubber sheet functioning as the contact plate 6 is fixed to the surfaces of the compressor housing 3 and the motor housing 4, the O-ring and the packing 7 can be omitted.

(Effects of the Embodiment) The packing 7 has a through hole 71.
And the heat of the motor housing 4 is
1 has a function of suppressing transmission to the low-pressure refrigerant, the three-phase inverter circuit 54, and the base plate 51, but the motor housing 4 and the contact plate 6 are replaced by protrusions provided on one of the two. Is also good.

[0043]

Embodiment 2 Another embodiment will be described below with reference to FIG. FIG. 3 is a schematic axial partial sectional view of the electric compressor.
In addition, since the refrigerant circuit itself other than the electric compressor integrated with the inverter is well known, the illustration and the description are omitted. (Overall configuration) 1 is a compressor part forming a part of a refrigeration cycle device for vehicle air conditioning, 2 is a motor part driving the compressor part 1, 3 is a compressor housing forming an outer shell of the compressor part, 4
Reference numeral denotes a motor housing which forms an outer shell of the motor unit 2, reference numeral 5 denotes an inverter unit which drives and controls the motor unit 2 formed of a three-phase synchronous motor, and reference numeral 7 denotes packing.

The housings 3 and 4 are coaxially connected by a through bolt (not shown) adjacent to the rotating shaft (not shown) so that the rotating shaft of the motor unit 2 drives the rotating shaft of the compressor unit 1. As a whole, it constitutes the electric compressor referred to in the present invention.

The inverter unit 5 includes a base plate 51,
Circuit accommodation room 5 formed by an outer shell composed of cover 52
3 and a three-phase inverter circuit 5
4, a smoothing capacitor 55, a wiring member (not shown) for connecting them, and other small circuit components (not shown).

The base plate 51 is made of aluminum and is fastened to the flat upper surface of the compressor housing 3 by bolts (not shown), and is further fastened to the motor housing 4 by bolts (not shown) via a packing 7 forming a heat insulating plate. I have.

The cover 52 is a bottomed rectangular box made of aluminum, and is fixed on the base plate 51 by bolts (not shown).

The three-phase inverter circuit 54 includes u, v, w,
It has a well-known circuit configuration in which a phase inverter circuit in which an upper arm element and a lower arm element for three phases are connected in series is connected in parallel and a DC voltage is applied from a battery (not shown).
A bus bar (only one is shown in FIG. 1) 56 that forms an AC output terminal of the three inverter circuits of the v and w phases protrudes in the axial direction. Upper arm element and lower arm element are each IG
Although the BT and the flywheel diode are connected in anti-parallel, further description is omitted because it is well known. In this embodiment, the three-phase inverter circuit 54 is used to simplify the description.
Has a single resin-molded semiconductor module configuration, but of course, various variations are possible. The three-phase inverter circuit 54 is in close contact with and fixed to the circuit mounting surface 540 of the base plate 51, and a smoothing capacitor 55 is mounted and fixed thereon, thereby forming a two-story structure as a whole.

The smoothing capacitor 55 is composed of an electrolytic capacitor housed in an aluminum case 551 and is connected in parallel with the three-phase inverter circuit 54 to absorb a high-frequency switching voltage applied from the three-phase inverter circuit 54 to a battery (not shown). I do. The case 551 of the smoothing capacitor 55 includes a cover (good heat conductive member referred to in the present invention) 52.
Is in close contact with the bottom surface (located at the upper side in FIG. 1) through grease having good thermal conductivity.

This embodiment is not characterized by the arrangement and shape of the three-phase inverter circuit 54 and the smoothing capacitor 55. For example, the smoothing capacitor 55 is closely attached to the base plate 51 and fixed, or a special frame is used. It may be arranged on the three-phase inverter circuit 54 at a distance from the three-phase inverter circuit 54.

The flanged resin sleeve 9 is an electrically insulating resin member, and is press-fitted through the base plate 51, the packing 7, and the motor housing 4. Sleeve 9
Has a flat cylindrical shape, and has three through holes (not shown) inside.

A three-phase synchronous motor (not shown) is accommodated in the motor housing 4 and connected to the ends of three armature windings of the three-phase synchronous motor. 41) individually penetrate the through holes of the resin sleeve 9 with a flange, and
3 protrudes. A male screw surface is formed at the tip of each output terminal 41, and a bus bar (only one is shown in FIG. 1) 56 protruding laterally from the three-phase inverter circuit 54 is individually connected to each output terminal 41 by the nut 10. Has been concluded.

(Assembling Order) Next, the assembling order of the inverter-integrated electric compressor will be described below.

The circuit components such as the three-phase inverter circuit 54 and the smoothing capacitor 55 are mounted, and the base plate 51 on which the necessary wiring is completed is brought into close contact with the compressor housing 3 via the heat conductive grease, and the motor is mounted via the packing 7. It is brought into close contact with the housing 4 and fastened and fixed with bolts (not shown). After that, the bus bar 56 is fastened to the output terminal 41,
The cover 52 may be fastened to the base plate 51.

(Operation) The high-pressure refrigerant discharged from the compressor unit 1 cools the motor unit 2 and is sent from the motor housing 4 to a condenser (not shown). Since the base plate 51 is in close contact with the compressor housing 3, particularly in the vicinity of the low-pressure refrigerant chamber, the base plate 51 is cooled well through the compressor housing 3 and is thermally shielded from the motor housing 4 by the packing 7. From being heated.

In this embodiment, the output terminal 41 for supplying power to the armature winding of the motor unit 2 is disposed on the peripheral wall of the motor housing 4 near the front end wall on the compressor housing 3 side. Although the inverter unit 5 is fixed to the compressor housing 3, the length of the bus bar 56 can be reduced.

[0057]

Embodiment 3 Another embodiment will be described below with reference to the drawings.

FIG. 4 is a schematic axial partial sectional view of the electric compressor. In addition, since the refrigerant circuit itself other than the inverter unit that controls the electric compressor is well known, illustration and description thereof are omitted. (Overall configuration) 5 is an inverter unit for driving and controlling the electric motor unit 2 composed of a three-phase synchronous motor, 6 is a contact plate, 8 is O
It is a ring.

The inverter unit 5 includes a base plate 51,
Circuit accommodation room 5 formed by an outer shell composed of cover 52
3 and a three-phase inverter circuit 5
4, a smoothing capacitor 55, a wiring member (not shown) for connecting them, and other small circuit components (not shown).

The base plate 51 is made of aluminum and is fastened to the contact plate 6 by bolts (not shown). At this time, the O-ring 8 has a long groove 511 described later.
Seal.

On the main surface of the base plate 51 on the contact plate 6 side, a long groove (low pressure refrigerant passage for cooling the base) 511 provided in a U-shape and a low pressure refrigerant inlet 512 communicating with one end of the long groove 511 are provided. Are formed. The low-pressure refrigerant inlet 512 is supplied with a low-pressure refrigerant from an evaporator (not shown) through an external pipe (not shown) connected to a pipe connecting cylinder 513 protruding from the upper surface of the base plate 51. The long groove 511 extends just below a three-phase inverter circuit 54 of the inverter unit 5 described later.

The cover 52 is a bottomed square box made of aluminum, and is fixed on the base plate 51 by bolts (not shown).

The three-phase inverter circuit 54 includes u, v, w,
It has a well-known circuit configuration in which a phase inverter circuit in which an upper arm element and a lower arm element for three phases are connected in series is connected in parallel and a DC voltage is applied from a battery (not shown).
A bus bar (only one is shown in FIG. 1) 56 that forms an AC output terminal of the three inverter circuits of the v and w phases protrudes in the axial direction. Upper arm element and lower arm element are each IG
Although the BT and the flywheel diode are connected in anti-parallel, further description is omitted because it is well known. In this embodiment, the three-phase inverter circuit 54 is used to simplify the description.
Has a single resin-molded semiconductor module configuration, but of course, various variations are possible. The three-phase inverter circuit 54 is in close contact with and fixed to the circuit mounting surface 540 of the base plate 51, and a smoothing capacitor 55 is mounted and fixed thereon, thereby forming a two-story structure as a whole.

The smoothing capacitor 55 is composed of an electrolytic capacitor housed in an aluminum case 551 and is connected in parallel with the three-phase inverter circuit 54 to absorb a high-frequency switching voltage applied from the three-phase inverter circuit 54 to a battery (not shown). I do. The case 551 of the smoothing capacitor 55 includes a cover (good heat conductive member referred to in the present invention) 52.
Is in close contact with the bottom surface (located at the upper side in FIG. 1) through grease having good thermal conductivity.

This embodiment is not characterized by the arrangement and shape of the three-phase inverter circuit 54 and the smoothing capacitor 55. For example, the smoothing capacitor 55 is closely attached to the base plate 51 and fixed, or a special frame is used. It may be arranged on the three-phase inverter circuit 54 at a distance from the three-phase inverter circuit 54.

The contact plate 6 is made of a thin aluminum flat plate and has a through hole 61 communicating with the other end of the long groove 511 of the base plate 51. The through-hole 61 is provided with a pipe connecting tubular portion 62 protruding from the lower surface of the contact plate 6.
The low-pressure refrigerant is supplied to a compressor unit (not shown) through an external pipe (not shown) connected to the compressor.

(Operation) The high-pressure refrigerant discharged from the compressor unit 1 cools the electric motor unit 2 and is sent from the motor housing 4 to a condenser (not shown). A low-pressure refrigerant is supplied to the compressor unit from an evaporator (not shown) through the cylinder 513, the long groove 511, and the cylinder 62, and the low-pressure refrigerant flowing through the long groove 511 cools the base plate 51, and the base plate 51 cools the three-phase inverter circuit 54, At the same time, the smoothing condenser 55 is cooled through the cover 52.

(Modification 1) The smoothing capacitor 55 can be cooled by the base plate 51 through a mount made of a good heat conducting member.

[Brief description of the drawings]

FIG. 1 is a schematic axial partial cross-sectional view of an electric compressor according to a first embodiment.

FIG. 2 is a plan view of the base plate of FIG. 1;

FIG. 3 is a schematic axial partial cross-sectional view of an electric compressor according to a second embodiment.

FIG. 4 is a schematic axial partial cross-sectional view of an electric compressor according to a third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor part 2 Motor part 3 Compressor housing 4 Motor housing 5 Inverter part 6 Contact plate 7 Packing (heat insulating plate) 8 O-ring 9 Resin sleeve 51 Base plate 511 Long groove 52 Cover (good heat conduction member) 54 Three-phase inverter Circuit (semiconductor element) 55 Smoothing capacitor 551 Case of smoothing capacitor

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H02K 5/20 H02K 5/20 9/08 9/08 Z 11/00 11/00 X F term (reference) 3H003 AA05 AB05 AC03 BE09 CD05 CF02 3H029 AA01 AA15 AB03 BB12 CC07 CC09 CC27 CC48 5H605 AA01 BB07 BB10 BB17 CC01 CC08 DD11 EC20 5H609 BB03 BB14 BB19 BB23 PP01 PP16 QQ03 QQ10 RR35 RR36 A09 RR70 BB01

Claims (8)

[Claims] An electric compressor having a compressor part forming a part of a refrigeration cycle device and an electric motor part driving the compressor part, wherein a motor housing and a compressor housing are coupled in an axial direction; An inverter unit having a semiconductor element for controlling the motor unit and a smoothing capacitor for reducing DC voltage pulsation, and being fixed to the motor housing, wherein the inverter unit includes: It has a base plate fixed and the case of the semiconductor element and the smoothing capacitor fixed directly or through a good heat conducting member, wherein the base plate is cooled by a base cooling low-pressure refrigerant passage through which a low-pressure refrigerant flows. Electric refrigeration cycle device. 2. The electric refrigeration cycle apparatus according to claim 1, further comprising: a contact plate that contacts a main surface of the base plate on the motor housing side; wherein the base cooling low-pressure refrigerant passage includes: a contact plate; An electric refrigeration cycle device comprising a long groove recessed in at least one of the base plates. 3. The electric refrigeration cycle apparatus according to claim 2, wherein the base plate and the contact plate are extended until the base plate and the contact plate come into contact with a peripheral wall of the compressor housing, and are attached to both the motor housing and the compressor housing. The abutting plate has a compressor-side opening communicating the low-pressure refrigerant suction port of the compressor housing and the other end of the long groove in the direction of the fastening, and is provided on a peripheral wall of the compressor housing. An electric refrigeration cycle device that is in contact with the refrigeration cycle device. 4. The electric refrigeration cycle apparatus according to claim 2, wherein the contact plate abuts on a pedestal protruding from a peripheral wall of the motor housing. apparatus. 5. The electric refrigeration cycle device according to claim 2, wherein the contact plate comes into contact with the motor housing via a heat insulating plate having thermal insulation. apparatus. 6. An electric compressor having a compressor part forming part of a refrigeration cycle device and an electric motor part for driving the compressor part, wherein an electric motor housing and a compressor housing are axially connected to each other; An inverter unit having a semiconductor element for controlling the motor unit and a smoothing capacitor for reducing DC voltage pulsation, the inverter unit being fixed to the motor housing, wherein the inverter unit includes the compressor housing An electric refrigeration cycle apparatus having a base plate which abuts the semiconductor element and the case of the smoothing capacitor directly or through a good heat conducting member. 7. An electric compressor having a compressor part forming a part of a refrigeration cycle device and an electric motor part driving the compressor part, wherein an electric motor housing and the compressor housing are connected in the axial direction; An inverter unit having a semiconductor element for controlling the motor unit and a smoothing capacitor for reducing DC voltage pulsation, and an inverter unit separately provided from the electric compressor, wherein the inverter unit includes the semiconductor An electric refrigeration cycle apparatus comprising a base plate to which an element and a case of a smoothing condenser are fixed directly or through a good heat conducting member, wherein the base plate also serves as a low-pressure refrigerant pipe. 8. The refrigeration cycle apparatus according to claim 7, further comprising: a contact plate that contacts a main surface of the base plate on a side opposite to the circuit mounting surface, wherein the base cooling low-pressure refrigerant passage includes: a contact plate; An electric refrigeration cycle device comprising a long groove recessed in at least one of the base plates.