JP5291436B2 - Inverter-integrated electric compressor - Google Patents

Description

  The present invention relates to an inverter-integrated electric compressor. In particular, the stability of a control circuit can be improved by shielding electromagnetic noise while maintaining the same degree of design freedom as before, and the vibration of the control board is effective. The present invention relates to an inverter-integrated electric compressor that can be effectively prevented, has excellent operational stability, and can be realized at low cost.

  For electric compressors, in particular, electric compressors mounted on vehicles, various countermeasures for vibration to protect electrical components from problems caused by long-time vibration have been proposed. For example, Patent Document 1 discloses a structure in which a motor drive circuit is covered with a resin mold material and embedded in the resin mold material as a structure of an electric compressor including a motor drive circuit including an inverter or the like. Are known.

Further, in the inverter-integrated electric compressor, electromagnetic noise emitted from the high voltage circuit may cause a malfunction such as a malfunction of the control circuit configured by the low voltage circuit. Is required. For example, in Patent Document 2, an electromagnetic shielding shield is provided between a power module that is a high-voltage circuit and a power module drive circuit that is a low-voltage circuit, whereby electromagnetic waves emitted from the high-voltage circuit toward the low-voltage circuit are disclosed. A switching room structure of an inverter device that shields noise is disclosed.
JP 2002-70743 A Japanese Patent No. 3729175

  However, in the invention disclosed in Patent Document 2, although improvement of the stability of an electric circuit by shielding electromagnetic noise has been realized, there is no particular mention or suggestion regarding vibration countermeasures.

  Therefore, an object of the present invention is to improve the stability of the control circuit by shielding electromagnetic noise while maintaining the design flexibility as high as before, and to effectively prevent the vibration of the control board. The object is to provide an inverter-integrated electric compressor excellent in operational stability at a low cost.

In order to solve the above problems, an inverter-integrated electric compressor according to the present invention includes a motor, a motor driving high-voltage circuit including the inverter, and a control board having a control low-voltage circuit. In an inverter-integrated electric compressor that is provided in a housing and includes a compressor mounted on a vehicle, a material that can shield electromagnetic noise emitted from the motor driving high-voltage circuit toward the control low-voltage circuit. The shield plate is interposed between the motor driving high voltage circuit and the control board, and the shield plate and the control board are fixed to each other, and both are fixed to a predetermined position in the compressor housing. , this said at least part of the fixed portion to the control board in the shield plate is formed in a shape that is bulged in a convex on the control board direction Consisting of those characterized by.

  In such an inverter-integrated electric compressor, electromagnetic noise emitted from the motor driving high voltage circuit in the direction of the control low voltage circuit is shielded by the shield plate. The malfunction of the circuit is surely prevented, and the operational stability of the entire compressor is improved. In addition, since the control board is fixed to a predetermined position in the compressor housing while being fixed to the shield plate, the positional relation between the control board and the shield plate is maintained at the predetermined positional relation for electromagnetic noise shielding. However, the vibration of the control board is prevented, the operational stability of the compressor is reliably maintained even during high-speed operation, and the life of the compressor is extended.

  Since the shield plate according to the present invention may be a thin plate and requires less installation space, it can be easily installed in an existing compressor and can be easily formed into a desired shape according to the shape of the installation site. Thus, the degree of freedom in designing the compressor can be maintained at the same high level as when a conventional shield plate is not installed. In addition, since the present invention can be substantially realized only by adding a shield plate, the operational stability of the compressor can be improved at a low cost with almost no influence on the weight of the entire compressor. The material of the shield plate according to the present invention is not particularly limited, but is preferably made of a metal or an alloy because electromagnetic noise can be reliably shielded and workability is excellent.

  Although it does not specifically limit in the said shield plate, It is preferable that the rib is provided. By providing the rib, the rigidity of the shield plate is improved, and the vibration of the control board is more effectively prevented.

At least a part of the fixing portion to the control board of the upper Symbol shield plates that are formed on the are bulged in a convex on the control board way shape. By forming the fixing portion in a convex shape, the contact area between both members when fixing the control board and the shield plate can be reduced, and the transmission of vibration from the shield plate to the control board is suppressed, so that the control board Vibration is suppressed. In addition, as will be described later, when the electrical component including the control board is provided in the housing space surrounded by the compressor housing, and the resin is filled in the housing space after the assembly is completed, the fixing portion bulges. Since the resin is filled in the gap formed between the control board and the shield plate, the control board is more reliably fixed and the vibration of the control board is more effectively prevented.

  In the present invention, when a noise filter is provided on the power supply side in the motor driving high voltage circuit, the shield plate is not particularly limited, but also for electromagnetic noise emitted from the noise filter toward the control low voltage circuit. It is preferable to be configured to be shieldable. With such a configuration, the malfunction of the control low-voltage circuit due to electromagnetic noise is more reliably prevented, and the operational stability of the entire compressor is improved.

  In the present invention, when the power line is connected to the motor driving high voltage circuit, the shield plate is not particularly limited, but also shields electromagnetic noise emitted from the power line toward the control low voltage circuit. It is preferable that the configuration is possible. With such a configuration, the malfunction of the control low-voltage circuit due to electromagnetic noise is further reliably prevented, and the operational stability of the entire compressor is improved.

  An inverter-integrated electric compressor according to the present invention is provided in an accommodation space in which an electric component including a motor driving high voltage circuit and a control board is surrounded by a compressor housing in order to achieve circuit insulation and vibration prevention of the electric component. The housing space may be filled with resin after assembly is completed, and at least a part of the electrical component may be sealed with a solidified filling resin. In such a configuration, although not particularly limited, it is preferable that an air vent hole is provided in the shield plate so as to uniformly fill the housing space with the resin. By providing such air vent holes, the generation and retention of bubbles in the resin is prevented, and the electrical components sealed with resin in the housing space are more securely fixed, and the operation stability of the entire compressor is improved. Improvement is realized.

  As described above, when the housing space for filling the resin is provided inside the compressor, the shield plate is preferably provided with a hole for filling the resin. By providing such a hole for filling the resin, it becomes possible to easily inject the resin into the part covered by the shield plate, and it is possible to reliably fill the resin over the entire predetermined part in the accommodation space. In addition, the electrical components sealed with resin in the housing space are more securely fixed, and the operational stability of the entire compressor is improved. The resin filling holes may be used as the above-described air vent holes, or may be different holes.

Application of an inverter-integrated electric compressor according to the present invention, since the excellent operational stability by preventing vibration of the shield and the control board of the electromagnetic noise can be realized, using a compressor susceptible vehicle the influence of vibration The In particular, it is suitable for use as a compressor for a vehicle air conditioner.

  As described above, according to the inverter-integrated electric compressor according to the present invention, the stability of the control circuit can be improved by shielding electromagnetic noise while maintaining the same degree of freedom in design as in the past. It is possible to effectively prevent the vibration of the substrate and realize a compressor having excellent operational stability at low cost.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an inverter-integrated electric compressor according to an embodiment of the present invention, and particularly shows an example in which the present invention is applied to a scroll-type electric compressor. In FIG. 1, the inverter-integrated electric compressor 1 includes a compression mechanism 2 including a fixed scroll 3 and a movable scroll 4. The movable scroll 4 is turned with respect to the fixed scroll 3 in a state in which the rotation is prevented via the ball coupling 5. A motor 7 is incorporated in the compressor housing (center housing) 6, and the main shaft 8 (rotary shaft) is rotationally driven by the built-in motor 7. The rotational motion of the main shaft 8 is converted into the turning motion of the movable scroll 4 via the eccentric pin 9 disposed on one end side of the main shaft 8 and the eccentric bush 10 rotatably engaged with the eccentric pin 9. ing. In this embodiment, a suction port 11 for sucking refrigerant as a fluid to be compressed is provided in the compressor housing (front housing) 12, and the sucked refrigerant is guided to the compression mechanism 2 through the motor 7 arrangement portion. The refrigerant compressed by the compression mechanism 2 is sent to the external circuit through the discharge port 13, the discharge chamber 14, and the discharge port 16 provided in the compressor housing (rear housing) 15.

  A housing space 20 is formed by being surrounded by the extending portion of the compressor housing 12 (front housing), and a motor drive circuit 21 is provided in the housing space 20. More specifically, the motor drive circuit 21 is provided in the housing space 20 on the outer surface side of the partition wall 22 with the refrigerant suction path side formed in the compressor housing 12. The motor drive circuit 21 feeds power to the motor 7 via a sealed terminal 23 (an output terminal of the motor drive circuit 21) attached through the partition wall 22 and a lead wire 24. The path side and the motor drive circuit 21 installation side are sealed. In the present embodiment, the motor drive circuit 21 is provided on the outer surface side of the partition wall 22 so that at least a part of the electrical components including the motor drive circuit 21 can exchange heat with the suction refrigerant via the partition wall 22. It can be cooled by the suction refrigerant. With this configuration, it is possible to automatically and appropriately cool an electrical component that easily generates heat (for example, the motor drive high voltage circuit 25 having an inverter function), maintain the predetermined performance of the motor drive circuit 21, and separately Since it is not necessary to provide a cooling device or the like, the structure can be simplified. Such a configuration is not limited to the scroll-type electric compressor, and can be applied to all types of inverter-integrated electric compressors in which the fluid to be compressed is a refrigerant.

  The motor drive circuit 21 includes a motor drive high voltage circuit 25 having an inverter function, and a control board 26 having a control low voltage circuit. Electric components such as a capacitor 27 are provided separately or integrally with the motor drive circuit 21. Is provided. Since the shield plate 31 capable of shielding electromagnetic noise is fixed in a state of being interposed between the motor driving high voltage circuit 25 and the control board 26, the control low voltage circuit provided on the control board is The motor drive high voltage circuit 25 is reliably protected from electromagnetic noise, and malfunctions such as malfunctions are prevented. The control board 26 is fixed to a convex fixing portion 32 provided on the shield plate 31 to prevent vibration. Therefore, the shield plate 31 can improve the electrical stability of the circuit and the physical stability of the electrical components, and an electric compressor having excellent operational stability can be realized. Note that, for the resin filling described later, the shield plate 31 is provided with an air vent hole 33 that can also be used as a resin filling hole.

  The motor drive circuit 21 is connected to an external power source (not shown) via a connector 28 as an input terminal. The opening side to the outside of the compressor housing 12 on which the electric parts including the motor drive circuit 21 are mounted is covered in a state of being sealed with a lid member 29, and these electric parts are protected by the lid member 29. .

  In the housing space 20, the electric components such as the motor drive circuit 21 and the capacitor 27 are arranged and then filled with the resin 34, and these are substantially entirely sealed by the solidified resin 34. As shown in the figure, the resin filling range is accommodated within the minimum necessary range in the accommodation space 20, and the overall weight of the compressor 1 is reduced. As described above, the shield plate 31 is provided with an air vent hole 33 that can also be used as a resin filling hole, and the generation and remaining of bubbles in the filled resin 34 is effectively prevented. The air vent hole 33 can also be used as a resin filling hole, and a gap is formed between the shield plate 31 and the control board 26 by a convex fixing portion 32. Also, resin filling is reliably achieved even at the portion shielded by the control board 26 and the shield plate 31, and the electrical components sealed in the accommodation space 20 are more securely fixed, and the operation stability of the entire compressor 1 is improved. Improvement is realized.

  FIG. 2 shows a schematic relationship among the accommodation space 20, the shield plate 31, and the control board 26 in the inverter-integrated electric compressor shown in FIG. The control board 26 provided with the control low voltage circuit is fastened to a fixing portion 32 formed on the shield plate 31 by screws 36. In the shield plate 31, the rib 35 is formed to improve rigidity, and a part of the plurality of fixing portions 32 is formed in a convex shape to minimize the contact area with the control board 26. Therefore, the transmission of vibration is reduced. Further, as described above, the air vent hole 33 that can also be used as the resin filling hole prevents the generation of bubbles in the filling resin 34, and the electric component sealed in the housing space 20 is more securely fixed. The

  The motor driving high voltage circuit 25 installed in the accommodation space 20 is connected to the power supply line 38 via the noise filter 37 and is protected from signal line conductive noise caused by the power supply line 38. These electric components are supplied with a high voltage from an external power source through the power supply line 38, and there is a possibility that strong electromagnetic noise that may affect other electric components may be emitted to the surroundings. The shield plate 31 mounted on the control board 26 is configured to shield not only the high voltage circuit 25 for driving the motor but also electromagnetic noise emitted from the noise filter 37 and the power supply line 38, so that the control board 26 can be shielded. The control low voltage circuit provided is protected, and the operational stability of the compressor 1 is ensured.

  An example of the above configuration is shown in FIG. In FIG. 3, the electric compressor 1 is provided with the motor drive circuit 21 as described above, and an output from the motor drive circuit 21 is sent to each motor winding of the built-in motor 7 via the sealing terminal 23 and the lead wire 24. When the power is supplied to 41, the motor 7 is rotationally driven, and compression by the compression mechanism 2 is performed. The motor drive circuit 21 includes a motor drive high voltage circuit 25 and a control low circuit provided with a motor control circuit 44 for controlling each power element 43 (switching element) of the inverter 42 in the motor drive high voltage circuit 25. A voltage circuit 45 is provided, and the control low voltage circuit 45 is formed on the control board 26 described above. Electric power from an external power source 46 (for example, a battery) is fed to the motor driving high voltage circuit 25 through the high voltage connector 47 and supplied to the inverter 42 via the noise filter 37 and the smoothing capacitor 27. The direct current from the power supply 46 is converted into a pseudo three-phase alternating current at 42 and then supplied to the motor 7. For example, low voltage power is supplied to the motor control circuit 44 via a control signal connector 49 from an air conditioning control device 48 of the vehicle. In FIG. 3, the control signal connector 49 and the high voltage connector 47 are illustrated at positions apart from each other, but in reality, they are installed in the same connector 28 shown in FIG. 1. . The shield plate 31 is fixed to the control board 26, and the shield plate 31 includes a motor driving high voltage circuit 25 and a control low voltage circuit 45 as shown in FIG. The motor driving high voltage circuit 25 is covered over a wide range as much as possible to suppress the influence of noise from the motor driving high voltage circuit 25 to the control low voltage circuit 45 side.

  The present invention can be applied to all types of inverter-integrated electric compressors, and in particular, excellent operational stability and vibration resistance are required, the required level of design freedom is high, and miniaturization and weight reduction are required. It is suitable as an inverter-integrated electric compressor for a vehicle air conditioner.

1 is a schematic longitudinal sectional view of an inverter-integrated electric compressor according to an embodiment of the present invention. FIG. 2 is a perspective view of an accommodation space forming portion, a shield plate, and a control board in the inverter-integrated electric compressor shown in FIG. 1. FIG. 2 is a circuit diagram for illustrating a shield plate installation portion in the inverter-integrated electric compressor shown in FIG. 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inverter integrated electric compressor 2 Compression mechanism 3 Fixed scroll 4 Movable scroll 5 Ball coupling 6 Compressor housing (center housing)
7 Motor 8 Spindle 9 Eccentric pin 10 Eccentric bush 11 Suction port 12 Compressor housing (front housing)
13 Discharge hole 14 Discharge chamber 15 Compressor housing (rear housing)
Reference Signs List 16 Discharge port 20 Accommodating space 21 Motor drive circuit 22 Partition wall 23 Sealed terminal 24 Lead wire 25 High voltage circuit for motor drive 26 Control board 27 Capacitor 28 Connector 29 Cover member 31 Shield plate 32 Fixing portion 33 Air vent hole 34 Filling resin 35 Rib 36 Screw 37 Noise filter 38 Power line 41 Motor winding 42 Inverter 43 Power element (switching element)
44 Motor control circuit 45 Low voltage circuit for control 46 External power supply 47 High voltage connector 48 Air conditioning controller 49 Control signal connector

Claims (8)

Inverter-integrated electric compression composed of a compressor mounted in a vehicle, in which a motor built-in motor drive high-voltage circuit including an inverter and a control board having a control low-voltage circuit are provided in a compressor housing A shield plate made of a material capable of shielding electromagnetic noise emitted from the motor driving high voltage circuit toward the control low voltage circuit, between the motor driving high voltage circuit and the control board. The shield plate and the control board are fixed to each other, and both are fixed to a predetermined position in the compressor housing, and at least a part of a fixing portion of the shield plate to the control board is the control board. An inverter-integrated electric compressor characterized by being formed in a shape bulging convexly in the direction . The inverter-integrated electric compressor according to claim 1, wherein a central portion of the control board is fixed to the shield plate. And ribs provided in the shield plate, the inverter-integrated electric compressor according to claim 1 or 2.   A noise filter is provided on the power supply side of the motor driving high voltage circuit, and the shield plate is configured to shield electromagnetic noise emitted from the noise filter toward the control low voltage circuit. An inverter-integrated electric compressor according to any one of claims 1 to 3.   The power supply line is connected to the high voltage circuit for driving the motor, and the shield plate is configured to shield electromagnetic noise emitted from the power supply line toward the control low voltage circuit. The inverter-integrated electric compressor according to any one of 1 to 4.   An electrical component including the motor driving high voltage circuit and the control board is provided in a housing space surrounded by a compressor housing, and after the assembly is completed, the housing space is filled with resin, and at least one of the electrical components 6. The shield plate has a structure hermetically sealed with a solidified filling resin, and air holes are provided in the shield plate so as to uniformly fill the housing space with the resin. An inverter-integrated electric compressor according to any one of the above.   The inverter-integrated electric compressor according to claim 6, wherein a hole for resin filling is provided in the shield plate. The inverter-integrated electric compressor according to any one of claims 1 to 7, comprising a compressor for a vehicle air conditioner.

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