JP2009201184A - Vehicle drive - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform a ventilation that lessens a pressure difference to outside when the pressure inside a case that accommodates a rotary electric machine drops in a vehicle drive. <P>SOLUTION: The vehicle drive 10 includes a PCU 20, which includes an inverter 22, and a transaxle 30, which includes rotary electric machines 34 and 36, and the inverter 22 and the rotary electric machines 34 and 36 are connected with each other by a cable 44. Space that the core inside the cable 44 passes is used as a ventilating path 70, and a one-way valve 60 is provided to connect with this ventilating path 70. The one-way valve 60 opens when the pressure in the internal space of a case 31 drops, and the internal space of the case 31 communicates with the internal space of an inverter casing 21 via the ventilating path 70. A discharge valve 42 opens when the pressure in the internal space of the case 31 goes up, thereby connecting the inside of the case 31 with outside air. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle drive device, and more particularly to a vehicle drive device in which a ventilation passage is provided in a case body that houses a rotating electrical machine.

  When a rotating electrical machine is used as the vehicle drive device, it is necessary to make the pressure inside the case housing the rotating electrical machine the same as the outside. For example, when the pressure inside the case decreases, it may be necessary to limit the drive voltage in order to ensure the insulation of the rotating electrical machine. Further, when the case includes a circulating medium for lubrication or cooling, there is a possibility that the circulating medium overflows outside the case when the pressure inside the case becomes high.

  Therefore, in Patent Document 1, in a motor driving device in which an inverter case is disposed in an upper portion where rainwater or the like is not applied and a motor case is disposed in a lower portion, a breather is provided in the inverter case, and a communication path is provided between the inverter case and the motor case. Thus, a configuration is disclosed in which the pressure difference between the motor case and the inverter case and the pressure difference between the inside and outside of the inverter case are eliminated by this communication path. Here, a metal rod having one end connected to the winding of the motor body and the other end connected to the inverter body, and a sleeve for insulating the metal rod from the inverter case and the motor case are provided. A communication path is formed between the two.

  Further, in Patent Document 2, as a breather structure for connecting the inner side and the outer side of a motor equipped in a vehicle, two solid cables in which a core wire is coated with an insulation coating and one hollow except for the core wire are disclosed. It is disclosed that an electric wiring harness in which a cable is bundled is used for driving a motor. It is stated that the air inside the motor is discharged inside the control box through the inner hole of the hollow cable.

  Patent Document 3 discloses a breather device provided in an automatic transmission of a vehicle, but includes a large-diameter first valve plate urged by a first spring and a small-diameter first urged by a second spring. A configuration is disclosed in which two valve plates are arranged to face each other via an interposition plate, and the interposition plate is provided with an intake hole at the center and an exhaust hole at the periphery. Here, the second valve plate can close or open only the intake hole based on the biasing force of the second spring, and the first valve plate can block or open only the exhaust hole based on the biasing force of the first spring. It is stated that you get.

JP-A-8-65945 Japanese Utility Model Publication No. 6-9318 JP 2007-127139 A

  Thus, the device which reduces this about the pressure difference inside and outside of the case body which accommodates a rotary electric machine is made | formed. In this case, if only a communication path is provided, for example, when there is a circulating medium in the case, the circulating medium may circulate to the outside. Therefore, it is conceivable to use a valve structure, but when the pressure inside the case is higher than the outside pressure, air etc. is released from the inside of the case to the outside, and conversely, when the pressure inside the case is lower than the outside pressure, It is necessary to inhale air from the outside. Therefore, the valve requires a bidirectional function, but this makes the structure complicated. Moreover, if only the circulation medium is prevented from overflowing outside, it is often sufficient to provide a discharge valve that allows air to escape from the inside of the case when the pressure inside the case is higher than the outside pressure. However, the discharge valve cannot handle when the pressure in the case becomes low. That is, the discharge valve alone cannot cope with the decrease in insulation of the rotating electrical machine due to the pressure decrease.

  An object of the present invention is to provide a vehicle drive device that can perform directional ventilation with a simple configuration in a case body that houses a rotating electrical machine. Another object of the present invention is to provide a vehicle drive device that can perform ventilation with directionality that reduces the pressure difference with the outside when the pressure inside the case body that houses the rotating electrical machine decreases. It is. The following means contribute to at least one of these purposes.

  A vehicle drive device according to the present invention houses a rotating electrical machine, and includes a case body containing a circulating medium therein, an inverter housed in an internal space of the inverter housing and connected to the rotating electrical machine, and an internal space of the case body And a one-way valve that opens when the pressure in the internal space of the case body is equal to or lower than a predetermined pressure, provided in the ventilation passage on the rotating electrical machine side of the ventilation passage. And.

  Further, the vehicle drive device according to the present invention stores a transaxle including a rotating electrical machine, a case body including a circulating medium in the internal space, and an inverter stored in the internal space of the inverter housing and connected to the transaxle. And a ventilation passage that communicates the internal space of the case body and the internal space of the inverter housing, and the rotating electrical machine side connecting portion of the ventilation passage, and the pressure of the internal space of the case body is equal to or lower than a predetermined pressure. And a one-way valve that is sometimes opened.

  Moreover, in the vehicle drive device according to the present invention, the ventilation passage is preferably a ventilation space passage that passes through the inside of the power cable that connects the rotating electrical machine and the inverter.

  Further, in the vehicle drive device according to the present invention, a discharge valve that is provided in the case body separately from the one-way valve of the ventilation passage and opens when the pressure in the internal space of the case body is equal to or higher than a predetermined pressure. It is preferable to provide.

  According to at least one of the above-described configurations, the vehicle drive device houses the rotating electrical machine and communicates the internal space of the case body including the circulating medium and the internal space of the inverter housing, and the rotation of the ventilation passage And a one-way valve that is provided at the electric-side connection portion and opens when the pressure in the internal space of the case body is equal to or lower than a predetermined pressure. Thereby, when the pressure inside the case body that houses the rotating electrical machine is reduced, ventilation having directionality that reduces the pressure difference from the outside can be performed.

  Further, according to at least one of the above-described configurations, the vehicle drive device houses a transaxle including a rotating electric machine, and communicates the internal space of the case body including the circulating medium and the internal space of the inverter housing. And a one-way valve that is provided at the rotating electrical machine side connection portion of the ventilation passage and opens when the pressure in the internal space of the case body is equal to or lower than a predetermined pressure. Thereby, when the pressure inside the case body that accommodates the transaxle decreases, it is possible to perform ventilation that has a directionality that reduces the pressure difference from the outside.

  Further, in the vehicle drive device, the ventilation passage is a ventilation space passage that passes through the inside of the power cable that connects the rotating electrical machine and the inverter, so there is no need to provide a special passage.

  Further, the vehicle drive device includes a discharge valve separately from the one-way valve of the ventilation passage. Thereby, both the pressure differences inside and outside the case body can be reduced.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following, a case body that houses a transaxle including a rotating electrical machine, that is, a transaxle case body, will be described as a case body for reducing the pressure difference between the inside and outside. An electric case body may be used. Further, although oil will be described as the circulation medium, any oil other than oil may be used as long as it is a lubrication or cooling circulation medium. For example, a case body in which cooling water circulates may be used.

  FIG. 1 is a diagram illustrating a state of the vehicle drive device 10 mounted on the vehicle 8. Here, the vehicle drive device 10 is distinguished from the engine 6 and refers to an electric drive device, and is shown as being configured by a PCU (Power Control Unit) 20 and a transaxle 30 including a rotating electrical machine. ing. As a means for reducing the pressure difference between the inside and outside of the case body of the transaxle 30, the discharge valve 42 for releasing the high pressure to the outside when the pressure of the case body is high, and the PCU 20 when the pressure of the case body is low. A ventilation passage 70 and a one-way valve 60 for venting from the side are shown.

  FIG. 2 is a detailed view of the vehicle drive device 10. In the following, elements similar to those in FIG. 1 are denoted by the same reference numerals, and redundant description is omitted. In the following, description will be made using the reference numerals in FIG. The vehicle drive device 10 includes the PCU 20 and the transaxle 30 as described above. The PCU 20 includes a circuit such as an inverter 22 and an inverter housing 21 that is a housing for housing these circuits. The transaxle 30 includes a transaxle body 32, a case body 31 that accommodates the transaxle body 32, and a circulating oil 40 that is accommodated in the internal space of the case body 31.

  The PCU 20 is disposed above the transaxle 30. Here, upward refers to the upper side of the vehicle 8 when viewed from the road surface. Therefore, the PCU 20 is arranged at a position that is not easily affected by water or the like from the road surface, while the transaxle 30 is arranged to be easily affected by water or the like from the road surface, particularly on the bottom side thereof. Here, the inverter casing 21 which is the casing of the PCU 20 is provided with a communication path communicating with the outside air. However, as described above, the communication path is less affected by water from the road surface. As a result, the inverter housing 21 can reduce the pressure difference between the inside and the outside relatively safely.

  The transaxle body 32 includes two rotating electric machines 34 and 36 and a planetary gear mechanism 38. In addition, a speed reduction mechanism or the like may be included. Here, one of the two rotating electrical machines 34 and 36 is a driving rotating electrical machine that drives the vehicle 8, and the other is a power generating rotating electrical machine. The two rotating electrical machines 34 and 36 and the engine 6 are connected to the planetary gear mechanism 38 to perform power distribution. In that sense, the planetary gear mechanism 38 is a power distribution mechanism having a function of distributing power between the rotating electrical machines 34 and 36 and the engine 6.

  The circulating oil 40 is a circulating medium filled in the case body 31 in order to lubricate and cool the rotating electrical machines 34 and 36, the planetary gear mechanism 38, and the like. As the circulating oil 40, the same oil as an ATF fluid that lubricates and cools an automatic transmission or the like can be used. The rotating electrical machines 34 and 36 are each housed in a rotating electrical machine case body, and the planetary gear mechanism 38 is also often housed in a housing. However, the circulating oil 40 is naturally circulated inside the rotating electrical machine case body and the housing. Flowing. Circulation is performed by the rotation of the rotating electrical machines 34 and 36 and the rotation of the planetary gear mechanism 38 itself. If necessary, a circulation pump can be used. As shown in FIG. 2, the circulating oil 40 does not fill the entire internal space of the case body 31, but is accommodated so as to fill the internal space with an appropriate amount. Therefore, inside the case body 31, the space above the circulating oil 40 is a space 41 with air.

  The cable 44 in FIG. 2 connects a circuit such as the inverter 22 inside the PCU 20 and the rotating electrical machines 34 and 36 and exchanges high-voltage power, and is also called a power cable. The connector 46 pulls the cable 44 from the inside of the case body 31 to the outside, and is a connection part having an airtight structure and a waterproof structure.

  The discharge valve 42 in FIG. 2 is a one-side valve having a function of opening when the pressure in the internal space of the case body 31 is equal to or higher than a predetermined pressure. Specifically, the discharge valve 42 can be configured to include a ventilation path, a valve body that can block the ventilation path, and a spring body that applies a biasing force to the valve body.

Here, the ventilation passage 70 indicated by a broken line in FIG. 2 is a ventilation passage provided so as to pass through the cable 44, while the valve 60 is provided so as to be connected to the ventilation passage 70, and It has a function of opening when the pressure in the internal space is equal to or lower than a predetermined pressure. Therefore, the ventilation passage 70 and the one-way valve 60 communicate with each other when the pressure in the internal space of the case body 31 is equal to or lower than a predetermined pressure, and communicate the case body 31 with the inverter housing 21. It is what you have. Thus, when the pressure inside the case body 31 is lowered, ventilation having directionality that reduces the pressure difference from the outside can be performed.

  FIG. 3 shows a detailed structure regarding the one-way valve 60 and the ventilation passage 70. In the following, elements common to those in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed description thereof is omitted. In FIG. 3, a state in which the rotating electrical machine 36 is disposed inside the case body 31 and the circulating oil 40 is filled is shown. The rotating electrical machine 36 is a three-phase synchronous rotating electrical machine, and the U-phase, V-phase, and W-phase winding terminals are drawn out. Here, the U-phase terminal is drawn out to the terminal block 48, and via the bus bar 50, A state in which the connector 46 is connected to the cable 44 is illustrated. The bus bar 50 and the cable 44 are connected by pulling out the core wire 52 of the cable 44 and mechanically and electrically connecting it to the end 53 of the metal bus bar 50 by an appropriate connection method such as caulking. Done in

  As described above, the connector 46 allows the cable 44 to pass between the case body 31 and the outside with an airtight structure and a waterproof structure. For example, a resin insulating plate is fitted into an aluminum die cast frame, It is possible to use a material that is brought into close contact with the case body 31 using an appropriate surface seal, seal ring, or the like and attached with an appropriate fastening member such as a bolt or a nut.

  A space 54 defined by an aluminum die-cast frame and a resin insulating plate is provided inside the connector 46, and in the space 54, a space between the core wire 52 of the cable 44 and the end portion 53 of the bus bar 50 is provided. Are connected. In this connection portion, the cable 44 exposes the core wire 52, and a space through which the core wire passes through the cable 44 serves as a ventilation passage 70, and the space 54 communicates with the inside of the inverter housing 21. As described above, since the inverter casing 21 communicates with the outside air, the space 54 eventually communicates with the outside air through the ventilation passage 70.

  The one-way valve 60 provided on the case body 31 side of the connector 46 is a directional valve provided between the space 54 inside the connector 46 and the space 41 with air in the case body 31. Since the space 54 inside the connector 46 is a space connected to the ventilation passage 70, the one-way valve 60 is provided at the connection portion of the ventilation passage 70 on the rotating electrical machine 36 side. On the other hand, the valve 60 includes a rubber packing that is a valve body 62 that can block an air passage provided on the space 54 side, and a spring body 64 that is an urging means that presses the valve body 62 against the space 54 side. Is done.

  On the other hand, the configuration of the valve 60 is substantially the same as the configuration of the discharge valve 42, but the discharge valve 42 has a function of opening when the pressure in the internal space of the case body 31 is equal to or higher than a predetermined pressure. On the other hand, the one-way valve 60 has a function of opening when the pressure in the internal space of the case body 31 is equal to or lower than a predetermined pressure. That is, the one-way valve 60 functions as a so-called intake valve.

  Therefore, when the pressure in the space 41 inside the case body 31 is equal to or lower than a predetermined pressure by the one-way valve 60 and the ventilation passage 70 passing through the inside of the cable 44, the one-way valve 60 opens and the space 41 communicates with the space 54. As described above, the space 54 and the internal space of the inverter housing 21 communicate with each other through the ventilation passage 70, and the inverter housing 21 and the outside air communicate with each other. The space 41 and the outside air communicate with each other. Thus, when the pressure in the space 41 inside the case body 31 is equal to or lower than a predetermined pressure, air is sucked into the case body 31 from the outside air, and the pressure difference between the inside of the case body 31 and the outside air is increased. Get smaller.

It is a figure which shows a mode that the vehicle drive device of embodiment which concerns on this invention is mounted in a vehicle. It is detail drawing of the vehicle drive device in embodiment which concerns on this invention. It is a detailed structural diagram regarding the one-way valve and the ventilation passage in the embodiment according to the invention.

Explanation of symbols

  6 engine, 8 vehicle, 10 vehicle drive device, 21 inverter housing, 22 inverter, 30 transaxle, 31 case body, 32 transaxle body, 34, 36 rotating electrical machine, 38 planetary gear mechanism, 40 circulating oil, 41, 54 Space, 42 Discharge valve, 44 Cable, 46 Connector, 48 Terminal block, 50 Bus bar, 52 Core wire, 53 End, 60 One-way valve, 62 Valve body, 64 Spring body, 70 Ventilation passage.

Claims (4)

A case body containing a rotating electrical machine and containing a circulating medium inside;
An inverter housed in the internal space of the inverter housing and connected to the rotating electrical machine;
A ventilation passage communicating the internal space of the case body and the internal space of the inverter housing;
A one-way valve that is provided at the rotating electrical machine side connection portion of the ventilation passage and opens when the pressure in the internal space of the case body is equal to or lower than a predetermined pressure;
A vehicle drive device comprising: A case body containing a transaxle including a rotating electrical machine and containing a circulating medium in an internal space;
An inverter housed in the internal space of the inverter housing and connected to the transaxle;
A ventilation passage communicating the internal space of the case body and the internal space of the inverter housing;
A one-way valve that is provided at the rotating electrical machine side connection portion of the ventilation passage and opens when the pressure in the internal space of the case body is equal to or lower than a predetermined pressure;
A vehicle drive device comprising: In the vehicle drive device according to claim 1 or 2,
The vehicle drive device characterized in that the ventilation passage is a ventilation space passage that passes through the inside of the power cable connecting the rotating electrical machine and the inverter. In the vehicle drive device according to any one of claims 1 to 3,
A vehicle drive device comprising a discharge valve that is provided in the case body separately from the one-way valve of the ventilation passage and opens when the pressure in the internal space of the case body exceeds a predetermined pressure.

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