JP2016118183A - Motor compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor compressor with high reliability in which dropout of damping resistance does not occur.SOLUTION: A motor compressor includes an electric motor, a compression mechanism, a housing mounted with the electric motor and the compression mechanism, a drive device storage part provided outside a motor housing 14 constituting the housing, and an inverter device, as a drive device, arranged in the drive device storage part. The inverter device has a multilayer substrate 27 having a plurality of wiring layers L1-L4, and in the wiring layers L2, L3, a first wiring pattern R1 and a second wiring patter R2 constituting damping resistance are formed, respectively.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an electric compressor.

The electric compressor includes a compression unit that compresses and discharges refrigerant, an electric motor that is a drive source of the compression unit, and an inverter device as a drive device for driving the electric motor. It is known that an inverter device is provided with a damping resistor on a substrate so that the amplitude of a ripple current generated by switching a switching element does not become too large due to resonance.
On the other hand, since the electric compressor transmits not only the vibration caused by driving the electric compressor itself but also the vibration of the vehicle, the inverter device integrated with the electric compressor is always exposed to the vibration.
As a countermeasure against vibration of the inverter device mounted on the electric compressor, for example, an electric compressor for an in-vehicle air conditioner disclosed in Patent Document 1 is known. In the electric compressor for an in-vehicle air conditioner disclosed in Patent Document 1, an inverter accommodating portion is provided on the outer periphery of a housing in which an electric motor and a compression mechanism are built, and DC power supplied from a high-voltage power source is supplied to the inside thereof. The inverter apparatus which converts into phase alternating current power and supplies electric power to an electric motor is accommodated. The power circuit board and the control board constituting the inverter device are screwed with screws at the corners of the fixed screw seats provided at a plurality of locations in the inverter accommodating portion. Further, at least one other pedestal having the same height as the fixed screw seat surface supporting the vicinity of the substantially intermediate position of the fixing screw pitch of the control board and / or the vicinity of the installation position of the large component on the control board is provided on the inverter housing portion side. More than one place is provided. An elastic body is interposed between another pedestal and the control board.

  According to this electric compressor for an in-vehicle air conditioner, since the control board is supported by at least one other pedestal, in addition to fixing the control board to the four fixed screw seat surfaces, control associated with vehicle vibration The vibration and deformation (bending, bending) of the substrate can be suppressed.

JP 2009-111491 A

  However, in the electric compressor for an in-vehicle air conditioner disclosed in Patent Document 1, the fixed screw seat surface and the pedestal are formed as separate members, and therefore the fixed screw seat surface and the pedestal may behave differently due to vibration. The board fixed to the fixing screw seat surface and the pedestal is likely to be greatly oscillated and deformed. In particular, when a damping resistor is provided in the inverter circuit, if the damping resistor falls off, a large current flows through the inverter circuit and breaks. Therefore, in the inverter circuit mounted on the electric compressor, the damping resistor Drop prevention measures are necessary.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a highly reliable electric compressor that does not cause a drop in damping resistance.

  In order to solve the above problems, an invention according to claim 1 includes an electric motor, a compression mechanism that compresses refrigerant by driving the electric motor, and a housing in which the electric motor and the compression mechanism are incorporated. An electric compressor comprising: a drive device housing portion provided outside the housing; and a drive device disposed in the drive device housing portion and controlling power supply to the electric motor, wherein the drive The apparatus has a multilayer substrate having a plurality of wiring layers, and at least one of the wiring layers has a wiring pattern constituting a damping resistor.

  According to the first aspect of the present invention, since the damping resistor is formed as a wiring pattern in at least one wiring layer of the multilayer substrate, the damping resistor does not drop from the substrate due to vibration, and has high reliability. It is possible to provide a machine.

  According to a second aspect of the present invention, in the electric compressor according to the first aspect, a fastening portion for fastening the multilayer board is provided in the drive device housing portion, and the wiring pattern constituting the damping resistor and the fastening The portion is characterized by being thermally coupled.

  According to the invention described in claim 2, when the current flows through the wiring pattern constituting the damping resistor, the wiring pattern generates heat. Incidentally, since the wiring pattern constituting the damping resistor and the fastening portion are thermally coupled, heat generated in the wiring pattern is transmitted to the fastening portion and radiated to the outside through the housing. Thus, since heat can be radiated through the fastening portion, the heat dissipation of the wiring pattern can be improved. Note that “thermally coupled” means that the wiring pattern and the fastening portion are not in physical contact, but the wiring pattern and the fastening portion can freely exchange heat (heat transfer). It points to being in.

  According to a third aspect of the present invention, in the electric compressor according to the second aspect, the fastening portion has a screw hole into which a fastening bolt is screwed, and the multilayer board is passed through the fastening bolt. The wiring pattern which has a hole and constitutes the damping resistor is formed at a position where no other wiring pattern is interposed between the wiring pattern and the through hole.

  According to the third aspect of the present invention, by forming the wiring pattern constituting the damping resistor at a position adjacent to the through hole, the heat generated in the wiring pattern constituting the damping resistor is promptly transmitted to the outside via the fastening portion. It is possible to dissipate heat.

  According to a fourth aspect of the present invention, in the electric compressor according to any one of the first to third aspects, the wiring layer is laminated on the first layer and the first layer via an insulating layer. The wiring pattern which comprises two layers and constitutes the damping resistor is provided in the first wiring pattern provided in the first layer and the second layer, and the first wiring pattern and the insulating layer are interposed therebetween. The first wiring pattern and the second wiring pattern are continuously arranged so as to alternately repeat the folding from one side to the other side and the folding from the other side to the one side. The first wiring pattern and the second wiring pattern are connected in series.

  According to the fourth aspect of the present invention, the wiring pattern constituting the damping resistor is provided in the first wiring pattern provided in the first layer and in the second layer, and is disposed opposite to the first wiring pattern via the insulating layer. The direction of the current flowing through the first wiring pattern and the direction of the current flowing through the second wiring pattern are opposite to each other in the wiring layer stacking direction. ing. Accordingly, the magnetic field generated by the current flowing through the first wiring pattern and the magnetic field generated by the current flowing through the second wiring pattern have the same magnitude and opposite directions, so that they cancel each other out. Is done. Thereby, an induction component can be reduced. In addition, since the first wiring pattern and the second wiring pattern are formed by continuous conductive lines so as to alternately repeat the folding from one side to the other side and the folding from the other side to the one side, The overall length can be increased, and the wiring pattern can be formed by effectively utilizing the limited space on the substrate.

  According to the present invention, it is possible to provide a highly reliable electric compressor in which the damping resistance does not drop.

It is a whole lineblock diagram showing a part of electric compressor concerning an embodiment of the present invention in a fracture surface. FIG. 2 is a cross-sectional view taken along the line AA in a state in which the cover body in FIG. 1 is removed, and shows a mounting state of the multilayer board. FIG. 3 is a cross-sectional view taken along the line BB in FIG. FIG. 3 is an enlarged view of a main part of a wiring pattern (first wiring pattern) in FIG. 2. It is a perspective view which shows typically the arrangement | positioning relationship between the 1st wiring pattern in a wiring pattern, and a 2nd wiring pattern.

(Embodiment of the present invention)
Hereinafter, an electric compressor according to an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is an overall configuration diagram showing a part of an electric compressor provided with an electric motor in a broken section. The left side of the electric compressor in FIG. 1 is a front side, and the right side of the electric compressor is a rear side. .
An electric compressor 10 shown in FIG. 1 includes an electric motor 12 that drives a rotating shaft 11, a compression mechanism 23 that compresses refrigerant by driving the electric motor 12, and a housing in which the electric motor 12 and the compression mechanism 23 are built. 13. The electric compressor 10 is specifically a scroll-type electric compressor.

The housing 13 includes a motor housing 14 in which the electric motor 12 is accommodated, and a front housing 15 in which the compression mechanism 23 is accommodated. The end surface of the motor housing 14 and the end surface of the front housing 15 are joined, and the motor housing 14 and the front housing 15 are integrally fixed by bolts 16. The housing 13 is a metal housing, and is formed of an aluminum-based metal material in the present embodiment.
The motor housing 14 includes a cylindrical cylindrical portion 17 and a rear partition wall 18 that is integrally formed with the cylindrical portion 17 and closes one end portion of the cylindrical portion 17. In other words, the motor housing 14 has a bottomed cylindrical shape.

A refrigerant gas inlet 19 is provided in a portion of the cylindrical portion 17 of the motor housing 14 near the rear partition wall 18. The suction port 19 is connected to an external refrigerant circuit (not shown), and the external refrigerant circuit communicates with the inside of the motor housing 14 via the suction port 19. During the compression operation of the electric compressor 10, the low-pressure refrigerant passes through the suction port 19 from the external refrigerant circuit and is sent into the motor housing 14.
A discharge chamber communicating with the compression mechanism 23 is formed inside the front housing 15. A discharge port 20 is formed in the front housing 15, and the discharge port 20 is connected to an external refrigerant circuit. During the compression operation of the electric compressor 10, the high-pressure refrigerant discharged from the compression mechanism 23 to the discharge chamber is sent from the discharge port 20 to the external refrigerant circuit.

  The electric motor 12 is a motor driven by three-phase AC power. The electric motor 12 includes a stator 21 fixed to the inner wall of the motor housing 14, and a rotor 22 inserted into the stator 21 and fixed to the rotating shaft 11. The stator 21 has a stator core 21A fixed to the inner wall of the motor housing 14, and a stator coil 21B wound around the stator core 21A.

The rear partition wall 18 of the motor housing 14 is provided with a drive device accommodating portion 24 having a box shape. The drive device accommodating portion 24 is provided outside the housing 13.
The drive device housing portion 24 includes a base member 28 provided on the outer surface of the rear partition wall 18 (a surface opposite to the electric motor 12), and a cover body 34 provided on the base member 28.
The base member 28 and the cover body 34 define a drive device housing portion 24 that houses an inverter device 36 as a drive device.
The cover body 34 and the base member 28 are fixed to the motor housing 14 with bolts 35.
An inverter device 36 is provided in the drive device housing portion 24. The inverter device 36 includes an inverter circuit 25 and other electronic components 26 and a multilayer board 27 to which the inverter circuit 25 and other electronic components 26 are fixed.
Although not shown, the electric motor 12 and the inverter device 36 are electrically connected. When the stator coil 21 </ b> B of the electric motor 12 is energized via the inverter device 36, the rotor 22 is rotated and connected to the rotating shaft 11. The compressed compression mechanism 23 is activated.

The inverter circuit 25 includes a switching element, receives power necessary for driving the electric compressor 10 from the outside, and converts the supplied DC power into AC power.
The base member 28 is formed of an aluminum-based metal material having excellent thermal conductivity, and includes a flat portion 29 that comes into contact with an outer surface of the rear partition wall 18 (a surface opposite to the surface on the electric motor 12 side), and a flat surface. A plurality of pedestals 30 are formed so as to protrude from the portion 29 into the drive device housing portion 24 and have screw holes 31 at the center. In this embodiment, the base 30 is formed in four places, and each is shown by 30A-30D (refer FIG. 2). The pedestal 30 corresponds to a fastening part.

The multilayer substrate 27 of the present embodiment is provided with four wiring layers. Hereinafter, the four wiring layers will be described as wiring layers L1, L2, L3, and L4 in order from the side away from the base member 28. An insulating layer is provided between the wiring layers L1 and L2, between the wiring layers L2 and L3, and between the wiring layers L3 and L4. The insulating layer is formed of an insulating member.
The wiring layers L1 to L4 are conductive wiring patterns made of copper foil. The wiring layer L2 in this embodiment corresponds to the first layer of the claims, and the wiring layer L3 corresponds to the second layer of the claims.

As shown in FIG. 1, an inverter circuit 25 and other electronic components 26 are attached to the surface of the wiring layer L1 opposite to the wiring layer L2 side and the surface of the wiring layer L4 opposite to the wiring layer L3 side. It has been.
In addition, as shown in FIG. 2, the multilayer substrate 27 has through holes 33 </ b> A to 33 </ b> D as through holes at four locations. The multilayer substrate 27 is arranged such that each of the through holes 33A to 33D is provided on the pedestals 30A to 30D, and the fastening bolt 32 inserted through the through holes 33A to 33D is screwed into the screw holes 31 of the pedestals 30A to 30D. By being inserted, it is fastened and fixed to the pedestals 30A to 30D.

As shown in FIGS. 2 and 3, the wiring pattern R constituting the damping resistor has a first wiring pattern R1 provided in the wiring layer L2 and a second wiring pattern R2 provided in the wiring layer L3. .
The first wiring pattern R1 and the second wiring pattern R2 are formed by continuous conductive lines so as to alternately repeat the folding from one side to the other side and the folding from the other side to the one side.

As shown in FIG. 4, the first wiring pattern R1 has linear portions S1 to Sn and connecting portions K1 to Kn. That is, the linear linear portions S1 to Sn having a predetermined length are arranged in parallel with a narrow interval, and the connecting portions K1 to Kn are arranged so that the linear portions S1 to Sn form a single linear pattern. It is connected with. More specifically, one end of the linear portion S1 and one end of the linear portion S2 adjacent to the linear portion S1 are connected by the connecting portion K1, and the other end of the linear portion S2 is connected. The end portion and the other end portion of the linear portion S3 adjacent to the linear portion S2 are connected by the connecting portion K2, and the one end portion of the linear portion S3 and the line adjacent to the linear portion S3 are connected. The end portion on one side of the shape portion S4 is connected by the connecting portion K3. Thereafter, the first wiring pattern R1 is formed by repeating this connection operation. The first wiring pattern R1 has a rectangular wave shape in the present embodiment. The second wiring pattern R2 has the same shape as the first wiring pattern R1.
The first wiring pattern R1 and the second wiring pattern R2 are formed adjacent to the through hole 33A, the fastening bolt 32 inserted through the through hole 33A, the first wiring pattern R1 and the second wiring pattern R2. Are formed at positions not interposing other wiring patterns.

  The widths of the linear portions S1 to Sn are made as short as possible, and the arrangement intervals of the linear portions S1 to Sn are made as small as possible to increase the length.

  As shown in FIG. 5, the first wiring pattern R1 and the second wiring pattern R2 have the same shape and are formed to face each other with an insulating layer interposed therebetween. Further, the end of the linear portion Sn in the first wiring pattern R1 and the end of the linear portion Sn in the second wiring pattern R2 are electrically connected by, for example, vias T. Thus, the first wiring pattern R1 and the second wiring pattern R2 are connected in series to form a wiring pattern R (damping resistor).

Since the wiring pattern R is formed by connecting the first and second long wiring patterns R1 and R2 in series, the resistance value of the wiring pattern R is the same as the resistance value of the first wiring pattern R1. The resistance value by the two wiring patterns R2 is added. Note that the resistance value of the wiring pattern R is determined by the total length obtained by adding the cross-sectional area of the linear portions S1 to Sn, the length of the first wiring pattern R1, and the length of the second wiring pattern R2. Note that the lengths of the first wiring pattern R1 and the second wiring pattern R2 are obtained by adding the lengths of the linear portions S1 to Sn and the lengths of the connecting portions K1 to Kn.
The wiring pattern R should be formed continuously so that the cross-sectional area is reduced by forming the width as small as possible, and the folding from one side to the other side and the folding from the other side to the one side are repeated alternately. The overall length is lengthened. The resistance value of the wiring pattern R is increased by reducing the cross-sectional area as much as possible and making the entire length as long as possible.

As shown in FIGS. 2 to 4, the first wiring pattern R1 and the second wiring pattern R2 are formed adjacent to the through hole 33A and so as to surround the through hole 33A.
By forming as described above, the first wiring pattern R1, the second wiring pattern R2, and the pedestal 30A are in a thermally coupled state. That is, the first wiring pattern R1 and the second wiring pattern R2 generate heat when a current flows, but the generated heat is transmitted to the pedestal 30A that is thermally coupled to the motor, via the flat portion 29. It is transmitted to the rear partition 18 of the housing 14.
Therefore, it is possible to quickly dissipate heat generated from the first wiring pattern R1 and the second wiring pattern R2.
Note that “thermally coupled” means that the first wiring pattern R1 and the second wiring pattern R2 and the pedestal 30A are not in physical contact, but the first wiring pattern R1 and the second wiring pattern The pattern R2 and the pedestal 30A indicate that heat exchange (heat transfer) is freely performed. Further, although the fastening bolt 32 and the inner surface forming the through hole 33A are in contact, the fastening bolt 32 and the first wiring pattern R1 and the second wiring pattern R2 are not in contact and are electrically insulated. ing.

The operation of the electric compressor 10 having the above configuration will be described.
Since the electric compressor 10 transmits not only vibration due to driving of the electric compressor 10 but also vibration of the vehicle when mounted on the vehicle, the multilayer board 27 integrated with the electric compressor 10 is Since it is always exposed to vibration, if a damping resistor is provided on the substrate, it may fall off due to vibration. However, since the damping resistor provided in the multilayer substrate 27 of the present embodiment is formed as a wiring pattern R in the wiring layer of the multilayer substrate 27, the damping resistor does not drop from the substrate due to vibration, and the highly reliable electric motor A compressor can be provided.

  In addition, since the first wiring pattern R1 and the second wiring pattern R2 generate heat when a current flows through the first wiring pattern R1 and the second wiring pattern R2, heat is generated in the multilayer substrate 27, and the multilayer substrate 27 There is a risk of adversely affecting the inverter circuit 25 and other electronic components 26 provided above. However, the first wiring pattern R1 and the second wiring pattern R2 of the present embodiment are formed adjacent to the through hole 33A and surrounding the through hole 33A so as to be thermally coupled to the pedestal 30A. . Therefore, the heat generated from the first wiring pattern R1 and the second wiring pattern R2 is transmitted to the pedestal 30A. And it is transmitted to the rear partition 18 of the motor housing 14 through the flat part 29 provided with the base 30A, and is radiated to the outside. As described above, according to the configuration of the present embodiment, in order to effectively use the motor housing 14 (housing 13) having a large heat capacity as the heat dissipation means for the first wiring pattern R1 and the second wiring pattern R2, a separate heat dissipation means is provided. Without this, the heat generated from the first wiring pattern R1 and the second wiring pattern R2 can be dissipated.

The wiring pattern R includes a first wiring pattern R1 provided in the wiring layer L2 and a second wiring pattern R2 provided in the wiring layer L3. The first wiring pattern R1 and the second wiring pattern R2 are in series. It is connected. The first wiring pattern R1 and the second wiring pattern R2 are formed of continuous conductive lines so as to alternately repeat the folding from one side to the other side and the folding from the other side to the one side.
In the first wiring pattern R1 and the second wiring pattern R2, the linear portions S1 to Sn and the connecting portions K1 to Kn overlap in the stacking direction of the wiring layers L2 and L3, and as shown in FIG. The direction P1 of the current flowing through the first wiring pattern R1 and the direction P2 of the current flowing through the second wiring pattern R2 are opposite to each other in the stacking direction of the wiring layers L2 and L3. For example, the direction P1 of the current flowing through the linear portion S1 of the first wiring pattern R1 and the second wiring pattern formed at a position overlapping in the stacking direction of the linear portion S1 of the first wiring pattern R1 and the wiring layers L2 and L3. The direction P2 of the current flowing through the linear portion S1 of R2 is opposite to each other.
For this reason, the magnetic field component generated by the current flowing through the first wiring pattern R1 and the second wiring pattern R2 is in the opposite direction. That is, the magnetic field generated by the current flowing through the first wiring pattern R1 and the magnetic field generated by the current flowing through the second wiring pattern R2 have the same magnitude and are opposite in direction. Cancel each other out. Thereby, an induction component can be reduced. When the induction component is large, it is difficult for the alternating current component to flow through the first wiring pattern R1 and the second wiring pattern R2.

The electric compressor 10 according to the embodiment of the present invention has the following effects.
(1) Since the damping resistor is provided as the wiring pattern R in the wiring layers L2 and L3 of the multilayer substrate 27, the damping resistor does not fall off from the substrate due to vibration, and a highly reliable electric compressor can be provided. It becomes.

(2) The first wiring pattern R1 and the second wiring pattern R2 generate heat when a current flows. Incidentally, the first wiring pattern R1 and the second wiring pattern R2 are formed adjacent to the through hole 33A, and the first wiring pattern R1 and the second wiring pattern R2 and the pedestal 30A are thermally coupled. Thereby, the heat generated from the first wiring pattern R1 and the second wiring pattern R2 is transmitted to the base 30A. Then, heat is radiated to the outside through the motor housing 14. As described above, since the motor housing 14 having a large heat capacity is effectively used as the heat radiating means, the heat generated from the first wiring pattern R1 and the second wiring pattern R2 can be radiated without providing a separate heat radiating means.

(3) In the first wiring pattern R1 and the second wiring pattern R2, the linear portions S1 to Sn and the connecting portions K1 to Kn overlap in the stacking direction of the wiring layers L2 and L3, and the first wiring pattern R1. The direction P1 of the current flowing through the second wiring pattern R2 and the direction P2 of the current flowing through the second wiring pattern R2 are opposite to each other in the stacking direction of the wiring layers L2 and L3. Therefore, the magnetic field generated by the current flowing through the first wiring pattern R1 and the magnetic field generated by the current flowing through the second wiring pattern R2 have the same magnitude and are opposite in direction, and therefore cancel each other. Offset. Thereby, an induction component can be reduced.

(4) The wiring pattern R is formed by making the width as small as possible, thereby reducing the cross-sectional area, and continuously turning back and forth from one side to the other side and from the other side alternately. The overall length is increased by forming. Therefore, the resistance value of the wiring pattern R can be adjusted by adjusting the cross-sectional area and the overall length. In addition, the wiring pattern R can be formed by effectively utilizing the limited space on the substrate.

The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the spirit of the invention. For example, the following modifications may be made.
In the embodiment of the present invention, the diameter of the pedestal 30 (30A) on which the multilayer substrate 27 is disposed may be increased to increase the contact area with the multilayer substrate 27. By increasing the contact area, the heat generated in the first wiring pattern R1 and the second wiring pattern R2 can be radiated more efficiently.
In the embodiment of the present invention, the pedestal 30 is described as being formed to protrude in the axial direction on the flat portion 29 of the base member 28. However, the base member 28 is not provided, and the outside of the rear partition wall 18 of the motor housing 14 is not provided. A pedestal may be provided directly on the surface side. Further, a pedestal may be provided to protrude from the outer peripheral surface of the cylindrical portion 17 of the motor housing 14.
In the embodiment of the present invention, the first wiring pattern R1 and the second wiring pattern R2 have been described as having a rectangular wave shape. However, the present invention is not limited to this, and for example, a sine wave shape, A triangular wave shape or the like may be used. That is, it may be formed continuously so that the folding from one side to the other side and the folding from the other side to the one side are repeated alternately, and other shapes may be used.
In the embodiment of the present invention, the wiring pattern R is divided and formed on the wiring layers L2 and L3 by the first wiring pattern R1 on the wiring layer L2 and the second wiring pattern R2 on the wiring layer L3. Although described, it may be formed in only one wiring layer.

DESCRIPTION OF SYMBOLS 10 Electric compressor 12 Electric motor 13 Housing 14 Motor housing 15 Front housing 18 Rear partition 23 Compression mechanism 24 Drive apparatus accommodating part 25 Inverter circuit 27 Multilayer board 28 Base member 29 Flat part 30 (30A-30B) Base 31 Screw hole 32 Fastening Bolt 33 (33A-33D) Through-hole 34 Cover body 35 Bolt L1-L4 Wiring layer R Wiring pattern (damping resistance)
R1 First wiring pattern R2 Second wiring pattern T Via

Claims (4)

An electric motor;
A compression mechanism that compresses the refrigerant by driving the electric motor;
A housing containing the electric motor and the compression mechanism;
A drive housing portion provided outside the housing;
An electric compressor provided with a driving device that is disposed in the driving device housing and controls power supply to the electric motor,
The driving device has a multilayer substrate having a plurality of wiring layers,
At least one of the wiring layers has a wiring pattern constituting a damping resistor. A fastening portion for fastening the multilayer substrate is provided in the drive device housing portion,
The electric compressor according to claim 1, wherein the wiring pattern constituting the damping resistor and the fastening portion are thermally coupled. The fastening portion has a screw hole into which a fastening bolt is screwed,
The multilayer board has a through hole through which the fastening bolt is inserted,
3. The electric compressor according to claim 2, wherein the wiring pattern constituting the damping resistor is formed at a position between the through hole and no other wiring pattern. The wiring layer has a first layer and a second layer stacked on the first layer via an insulating layer,
The wiring pattern constituting the damping resistor includes a first wiring pattern provided on the first layer and a second wiring provided on the second layer and arranged to face each other via the first wiring pattern and the insulating layer. Pattern
The first wiring pattern and the second wiring pattern are formed of continuous conductive lines so as to alternately repeat the folding from one side to the other side and the folding from the other side to the one side,
The electric compressor according to any one of claims 1 to 3, wherein the first wiring pattern and the second wiring pattern are connected in series.

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