JP-7855987-B2 - Electric compressor

JP7855987B2JP 7855987 B2JP7855987 B2JP 7855987B2JP-7855987-B2

Inventors

伊藤駿
白石和洋
永田芳樹
川島隆
深作博史
安保俊輔

Assignees

株式会社豊田自動織機

Dates

Publication Date: 20260511
Application Date: 20221031

Claims (3)

A compression section that compresses the fluid, A motor that drives the compression section, It comprises an inverter device housed in a metal housing that drives the motor, The inverter device is, An inverter circuit that converts DC power to AC power, A noise reduction unit is provided on the input side of the inverter circuit and reduces common-mode noise and normal-mode noise contained in the DC power input to the inverter circuit. The system comprises a circuit board on which the inverter circuit and the noise reduction unit are mounted, The noise reduction unit is Common mode choke coil, The system comprises a smoothing capacitor that, together with the common mode choke coil, constitutes a low-pass filter, The common mode choke coil is, A ring-shaped core, A pair of windings wound around the core, The system comprises an annular conductor covering both of the pair of windings, The conductor is divided into a first metal plate and a second metal plate that form the annular shape. An electric compressor in which an induced current flows in the circumferential direction of the ring between the first metal plate and the second metal plate in such a way as to resist the change in leakage magnetic flux from the core, The circuit board is positioned relative to the housing with the common mode choke coil in between. The second metal plate is A main body portion is positioned with the pair of windings sandwiched between the first metal plate, It has a pair of extending portions that extend from the main body toward the housing, The housing has a pair of recesses, Of the first metal plate and the second metal plate, at least the second metal plate is thermally connected to the housing by the tip of each of the extended portions being inserted into each of the recesses, The first metal plate is thermally connected to the second metal plate, An electric compressor characterized in that at least one of the electrical resistance and thermal resistance values in the current path of the induced current is smaller for the second metal plate than for the first metal plate.
The first metal plate has a pair of upright portions that stand up toward the housing, The electric compressor according to claim 1 , characterized in that each of the upright portions is inserted into each of the recesses and is thermally connected to the housing.
The conductor comprises a plurality of joining portions that metallically join the tip portion of each extended portion to each upright portion, The electric compressor according to claim 2 , characterized in that the joint portion is arranged inside each of the recesses and is thermally connected to the housing.

Description

This invention relates to an electric compressor. An electric compressor comprises a compression unit, a motor, and an inverter device. The compression unit compresses the fluid. The motor drives the compression unit. The inverter device is housed in a metal housing. The inverter device drives the motor. The inverter device comprises an inverter circuit, a noise reduction unit, and a circuit board. The inverter circuit converts DC power to AC power. The noise reduction unit is located on the input side of the inverter circuit. The noise reduction unit reduces common-mode noise and normal-mode noise contained in the DC power input to the inverter circuit. The inverter circuit and the noise reduction unit are mounted on the circuit board. The noise reduction unit includes a common-mode choke coil and a smoothing capacitor. The smoothing capacitor, together with the common-mode choke coil, constitutes a low-pass filter. A common mode choke coil comprises an annular core, a pair of windings, and an annular conductor. The pair of windings are wound around the core. The conductor covers both windings. For example, in Patent Document 1, the conductor is divided into a first metal plate and a second metal plate that form an annular shape. An induced current flows in the circumferential direction of the annular shape between the first and second metal plates, resisting changes in leakage magnetic flux from the core. Japanese Patent Publication No. 2021-168561 This is a side cross-sectional view of an electric compressor in an embodiment.This is a circuit diagram showing the electrical configuration of an electric compressor.This is a disassembled perspective view of a common mode choke coil.This is a cross-sectional view showing a part of an electric compressor. An embodiment of the electric compressor will be described below with reference to Figures 1 to 4. The electric compressor of this embodiment is used, for example, in a vehicle air conditioning system. <Vehicle air conditioning system 10> As shown in Figure 1, the vehicle air conditioning system 10 comprises an electric compressor 11 and an external refrigerant circuit 12. The external refrigerant circuit 12 supplies refrigerant as a fluid to the electric compressor 11. The external refrigerant circuit 12 includes, for example, a heat exchanger and an expansion valve. The vehicle air conditioning system 10 provides heating and cooling to the vehicle interior by compressing the refrigerant with the electric compressor 11 and by performing heat exchange and expansion of the refrigerant with the external refrigerant circuit 12. The vehicle air conditioning system 10 is equipped with an air conditioning ECU 13. The air conditioning ECU 13 controls the entire vehicle air conditioning system 10. The air conditioning ECU 13 is configured to understand parameters such as the interior temperature and the set temperature of the car air conditioner. Based on these parameters, the air conditioning ECU 13 transmits various commands, such as ON/OFF commands, to the electric compressor 11. <Basic configuration of the electric compressor 11> The electric compressor 11 is equipped with a housing 14. The housing 14 is made of a heat-conductive metal material such as aluminum. Therefore, the housing 14 is made of metal. The housing 14 is grounded to the vehicle body. The housing 14 comprises an intake housing 15 and a discharge housing 16. The intake housing 15 and the discharge housing 16 are assembled to each other. The intake housing 15 has a plate-shaped end wall 15a and a cylindrical peripheral wall 15b. The peripheral wall 15b extends cylindrically from the outer circumference of the end wall 15a. The discharge housing 16 is assembled to the intake housing 15 with its opening closed. This creates an internal space within the housing 14. The housing 14 has an intake port 14a. Refrigerant is drawn into the intake port 14a from the external refrigerant circuit 12. Therefore, refrigerant is drawn into the housing 14. The intake port 14a is formed in the peripheral wall 15b of the intake housing 15. The intake port 14a is formed in the peripheral wall 15b of the intake housing 15, closer to the end wall 15a than the discharge housing 16. The housing 14 also has a discharge port 14b. The discharge port 14b discharges refrigerant to the external refrigerant circuit 12. The discharge port 14b is formed in the discharge housing 16. The electric compressor 11 comprises a rotating shaft 17, a compression unit 18, and a motor 19. The rotating shaft 17, the compression unit 18, and the motor 19 are housed within a housing 14. The rotating shaft 17 is supported in a rotatable manner relative to the housing 14. The rotating shaft 17 is positioned within the housing 14 such that its axial direction coincides with the axial direction of the peripheral wall 15b. The compression unit 18 is housed within the suction housing 15. The compression unit 18 is a scroll type, for example, composed