Drive device

Abstract

To provide a drive device configured so as not to give influence to insulation capability of an inverter device.SOLUTION: A drive device comprises: a rotary electric machine; and an inverter device disposed above the rotary electric machine so as to supply / receive power to / from the rotary electric machine. The rotary electric machine is accommodated in a housing. The housing has a recess in its upper portion, the recess being surrounded by a wall-like peripheral portion. The inverter device has an inverter cover. An electric component is disposed on the inner surface of the inverter cover. The inverter cover is fixed to the housing to accommodate the electric component in the recess. The inverter cover is provided with a contact surface that comes into contact with an end surface of the peripheral portion via a seal material. The contact surface is provided with a wall portion extended over the end surface of the peripheral portion at a position spaced apart from the peripheral portion toward the inner peripheral side, along an inner periphery of the contact surface.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a drive device.

Background Art

[0002] In a drive device, a configuration is known in which an inverter device that exchanges power with a rotating electrical machine is housed in the housing of the rotating electrical machine to reduce the size of the device.

[0003] Patent Document 1 discloses a configuration in which a motor housing is composed of a housing body and a cover, an electric circuit unit (inverter device) is fixed to the cover, and the cover closes the housing body, so that the motor and the inverter device are respectively housed in the motor housing.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

[0005] In a configuration such as the prior art, a sealing material for waterproofing is usually arranged between the cover to which the inverter device is fixed and the housing body.

[0006] Here, when the cover is removed from the housing and then reassembled for maintenance of the inverter device, it is necessary to remove the sealing material fixed between the cover and the housing. At this time, if fragments of the removed sealing material adhere to the inverter device, it may affect the insulation of the inverter device.

[0007] The present invention has been made in view of such problems, and an object thereof is to provide a drive device configured not to affect the insulation of the inverter device.

[0008] One embodiment of the present invention is applied to a drive device including a rotating electrical machine and an inverter device disposed above the rotating electrical machine and configured to exchange power with the rotating electrical machine. The rotating electrical machine is housed in a housing having, at its upper part, a recess surrounded by a peripheral portion with a wall-like periphery. The inverter device has an inverter cover with electrical components disposed on the inner surface thereof, and when the inverter cover is fixed to the housing, the electrical components are housed in the recess. The inverter cover includes a contact surface that contacts the end surface of the peripheral portion via a sealing material. The contact surface includes a wall portion extending along the inner periphery of the contact surface and extending beyond the end surface of the peripheral portion at a position spaced more inward than the peripheral portion.

[0009] According to the present invention, since a wall portion is provided along the inner periphery of the contact surface of the inverter cover and extends more than the peripheral portion, when removing the sealing material fixed to the contact surface, the wall portion functions as a baffle plate, preventing fragments of the sealing material or the like from entering the inside of the inverter cover where the electrical components are fixed. Thereby, it is possible to avoid deterioration of the insulation of the inverter device.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings and the like.

[0012] FIG. 1 is a configuration diagram of a drive device 1 according to an embodiment of the present invention.

[0013] The drive device 1 is configured by housing a power conversion device (inverter device) 10 and a rotating electric machine (motor) 20 in a housing 30. The drive device 1 is mounted on, for example, an electric vehicle, and drives the electric vehicle by driving the motor 20.

[0014] The inverter device 10 receives power supply from a battery (not shown), converts it into power suitable for driving the motor 20, and supplies it to the motor 20. Further, upon receiving the regenerative power of the motor 20, it converts this into power suitable for charging the battery and charges the battery.

[0015] The motor 20 drives the electric vehicle by transmitting rotation to the drive wheels. The motor 20 also functions as a generator that generates regenerative power when the electric vehicle decelerates.

[0016] The inverter device 10 and the motor 20 are housed in the housing 30. The housing 30 includes a cylindrical portion 31 that houses the motor 20 inside, and a recess 32 that is above the cylindrical portion 31, surrounded by a peripheral portion 321 on the periphery, and has an open upper portion. The recess 32 is formed by a peripheral portion 321 configured as a wall covering four sides, and is configured in a substantially rectangular box shape.

[0017] An inverter cover 34 is fixed above the recess 32. The inverter cover 34 has a box shape, and electrical components 11 are fixed to the inner surface of its ceiling portion so as to face the motor 20 side. By fixing the inverter cover 34 to the peripheral portion 321 of the housing 30, the inverter cover 34 and the recess 32 form a housing chamber 35 that houses the electrical components 11 of the inverter device 10. These housing 30 and inverter cover 34 are formed of a lightweight alloy such as aluminum.

[0018] A sealing material F is interposed between the inverter cover 34 and the housing 30 so that rainwater and dust do not enter. The sealing material F is constituted by, for example, a liquid gasket (FIPG: Formed In Place Gasket).

[0019] FIG. 2 is an explanatory view of the inverter device 10 and is a perspective view showing the inverter device 10 upside down (backward). FIG. 3 shows an enlarged view of part A in FIG. 1.

[0020] The inverter device 10 is configured such that the electrical components 11 are fixed to the ceiling portion (lower surface in FIG. 2) of the inverter cover 34. The electrical components 11 include a power module, a smoothing capacitor, etc. A bus bar 15 for transmitting power to the motor 20 projects from the electrical components 11. The bus bar 15 is composed of three phases: a U-phase bus bar 15U, a V-phase bus bar 15V, and a W-phase bus bar 15W. The three-phase bus bars 15 are each formed in a plate shape from a conductive metal (for example, copper).

[0021] The inverter cover 34 has a rectangular shape (rectangle) in plan view and is composed of a flat ceiling portion 34a and side portions 340 surrounding the periphery thereof.

[0022] As shown in FIG. 3, the side portion 340 has a contact surface 340a that contacts the end surface 321a of the peripheral portion 321 of the housing 30 on the housing 30 side. A sealing material F made of FIPG is disposed between the contact surface 340a and the end surface 321a.

[0023] Next, the sealing material F disposed between the contact surface 340a and the end surface 321a will be described.

[0024] At the time of assembling the drive device 1, the sealing material F is applied in advance to at least one of the end surface 321a of the peripheral portion 321 of the housing 30 and the end surface 321a of the side portion 340 of the inverter cover 34. After combining these, when the sealing material F cures, the housing 30 and the inverter cover 34 are fixed in a watertight state by the sealing material F interposed between the contact surface 340a and the end surface 321a.

[0025] When performing maintenance on the inverter device 10, the inverter cover 34 may be removed from the housing 30. In this case, in order to apply a new sealing material F during reassembly, it is necessary to remove the sealing material F remaining on the end face 321a of the housing 30 and the contact surface 340a of the inverter cover 34.

[0026] Specifically, the inverter device 10 removed from the housing 30 is installed upside down as shown in FIG. 2, and an operator uses a spatula or the like to scrape off the sealing material F remaining on the contact surface 340a of the inverter cover 34. In this operation, fragments of the scraped-off sealing material F may enter the inside of the inverter cover 34.

[0027] The fragments of the scraped-off sealing material F may be mixed with metal pieces scraped from the contact surface 340a of the inverter cover 34 together with the sealing material F. Therefore, if fragments of the sealing material F enter the inside of the inverter cover 34 and adhere to the electrical component 11, the insulation of the inverter device 10 may deteriorate. To prevent this, for example, it is conceivable to attach masking tape or the like to the inner peripheral side of the contact surface 340a of the inverter cover 34 to prevent fragments of the sealing material F or the like from entering the inverter device 10. However, since the gap between the inverter cover 34 and the electrical component 11 is small, it is difficult to fix the masking tape in this gap, resulting in an increase in the number of working hours.

[0028] Therefore, in this embodiment, the insulation of the inverter device 10 is prevented from deteriorating by configuring as follows.

[0029] As shown in FIG. 3, the contact surface 340a of the inverter cover 34 includes a wall portion 341 that extends beyond the end surface 321a of the peripheral portion 321 at a position spaced inwardly from the peripheral portion 321 of the housing 30. The wall portion 341 is provided along the inner circumference of the contact surface 340a over the entire inner circumference of the contact surface 340a. The wall portion 341 of the inverter cover 34 is formed with a slight gap from the peripheral portion 321, and in a state where the inverter cover 34 is fixed to the housing 30, the wall portion 341 is not in contact with the peripheral portion 321.

[0030] In this way, by forming the wall portion 341 to stand up on the contact surface 340a, as shown in FIG. 2, when the inverter device 10 is turned over, the wall portion 341 will be located above the contact surface 340a. Therefore, when the work of scraping off the sealing material F is performed, even if fragments of the sealing material F are generated, the fragments of the sealing material F are blocked by the wall portion 341 and are prevented from entering the inside of the inverter cover 34.

[0031] Thereby, when the inverter device 10 is maintained, it is possible to prevent fragments of the sealing material F from adhering to the electrical components 11, so that deterioration of the insulation of the inverter device 10 can be avoided.

[0032] Next, the combination of the housing 30 and the inverter cover 34 will be described. FIG. 4 is an explanatory diagram when the inverter device 10 is turned over and viewed in plan, and FIG. 5 is a cross-sectional view taken along the line V-V in FIG. 4.

[0033] In the present embodiment, as shown in FIG. 5, a part of the wall portion 341 is provided with an inscribed portion 342 formed to project to the outer peripheral side of the wall portion 341. The inscribed portion 342 abuts against the peripheral portion 321 of the housing 30 from the inner peripheral side.

[0034] As shown in FIG. 4, the inscribed portion 342 is arranged at one location on each of the opposing short sides (the first short side S1 and the second short side S2) and at one location on each of the opposing long sides (the first long side L1 and the second long side L2) in the rectangular inverter cover 34.

[0035] In the first short side S1, the three-phase bus bars 15 (15U, 15V, 15W) are arranged in proximity. The three-phase bus bars 15 are in a flat plate shape and are arranged in parallel so as to face the first short side S1. In this first short side S1, an inscribed portion 342 (first inscribed portion 342a) that forms a plane parallel to the wall portion 341 protruding to the outer peripheral side of the wall portion 341 is provided on a part of the wall portion 341. The first inscribed portion 342a is provided at a position corresponding to the three-phase bus bars 15. For example, the first inscribed portion 342a is arranged to face the W-phase bus bar 15W.

[0036] In the first long side L1 and the second long side L2, a second inscribed portion 342b and a third inscribed portion 342c are provided so as to face each other at the extension in the width direction of the three-phase bus bars 15.

[0037] Furthermore, on the second short side S2 facing the first short side S1, a fourth inscribed portion 342d is provided at a position facing the first inscribed portion 342a.

[0038] As shown in FIG. 5, the inscribed portion 342 is formed to protrude to the outer peripheral side of the wall portion 341. The inscribed portion 342 is formed to stand up from the contact surface 340a, and its standing height is formed lower than that of the wall portion 341.

[0039] Furthermore, a groove portion 343 recessed more than the contact surface 340a is formed at the position where the inscribed portion 342 stands up from the contact surface 340a. That is, the groove portion 343 is formed on the contact surface 340a outside the root portion of the inscribed portion 342.

[0040] In this way, by forming the inscribed portion 342 together with the wall portion 341 on the abutting surface 340a of the inverter cover 34, it is configured such that positioning is performed when the inverter cover 34 is assembled to the housing 30. That is, when the inscribed portion 342 abuts on each of the four sides of the peripheral portion 321 of the housing 30 from the inner peripheral side, the position of the inverter device 10 with respect to the housing 30 is defined. At this time, each inscribed portion 342 is in a press-fitted state when it abuts on the peripheral portion 321, and the inscribed portion 342 receives stress. However, by providing the groove portion 343, stress concentration at the standing portion between the abutting surface 340a and the inscribed portion 342 is prevented.

[0041] With such a configuration, since the inverter cover 34 is positioned on the housing 30, the configurations such as locating pins and locating holes for positioning them can be omitted.

[0042] Furthermore, since the standing height of the inscribed portion 342 is lower than that of the wall portion 341, when the inverter cover 34 is assembled to the housing 30, the wall portion 341 serves as a guide, making the assembly easier. Note that the wall portion 341 and the inscribed portion 342 may have the same standing height, or the wall portion 341 and the inscribed portion 342 may have the same standing height and their tip portions may be formed to be tapered inward.

[0043] Furthermore, since the inverter cover 34 is positioned on the housing 30, the positioning between the three-phase bus bars 15 of the inverter device 10 and the fixed portion on the motor 20 side is also performed.

[0044] That is, by providing the second inscribed portion 342b and the third inscribed portion 342c on the first long side L1 and the second long side L2, respectively, so as to face each other, the inverter cover 34 is clamped in the short side direction by the peripheral portion 321 of the housing 30, and the position of the three-phase bus bars 15 in the plate direction is defined. Thereby, the three-phase bus bars 15 and the fixed portion on the motor 20 side are positioned.

[0045] Further, by providing the first inscribed portion 342a and the fourth inscribed portion 342d on the first short side S1 and the second short side S2 respectively, the inverter cover 34 is longitudinally clamped by the peripheral portion 321 of the housing 30, and the position of the three-phase bus bar 15 in the plate thickness direction is defined.

[0046] Since the bus bar 15 is easily deformed in the plate thickness direction, it is not necessary to strictly define the position in the plate thickness direction. Therefore, in the inverter cover 34, the positioning in the plate thickness direction near the bus bar 15 may be performed only by the first inscribed portion 342a provided on the first short side S1, and the fourth inscribed portion 342d of the second short side S2 may be omitted.

[0047] Also, as shown in FIG. 4, the width D1 of the seating surface where the contact surface 340a of the first short side S1 and the end surface 321a are in contact is configured to be larger than the width D2 of the seating surface where the contact surfaces 340a of the other sides (the second short side S2, the first long side L1, and the second long side L2) and the end surface 321a are in contact. Thereby, in the operation of removing the inverter cover 34 from the housing 30 during the maintenance of the inverter device 10, the first short side S1 is used as a portion where a tool such as a spatula is inserted when prying these open.

[0048] As a result, the tool can be inserted deeper, and it is not necessary to adjust the insertion depth of the tool, so the working efficiency is improved. In addition, on the other sides, since the wall portion 341 is formed, the tool does not penetrate into the inverter device 10, so that fragments of the sealing material F generated in this operation are prevented from adhering to the inside of the inverter device 10. Further, since the inverter cover 34 is removed from the housing 30 near the bus bar 15, the bus bar 15 fixed to the motor 20 can be easily removed.

[0049] As described above, the present embodiment is a drive device 1 including a motor 20 as a rotating electrical machine and an inverter device 10 disposed above the motor 20 and configured to exchange power with the motor 20. The motor 20 is housed in a housing 30, and the housing 30 has a recess 32 at its upper portion surrounded by a peripheral portion 321 with a wall-like periphery. The inverter device 10 has an inverter cover 34, electrical components 11 are disposed on the inner surface of the inverter cover 34, and by fixing the inverter cover 34 to the housing 30, the electrical components 11 are housed in the recess 32. The inverter cover 34 includes a contact surface 340a that contacts the end surface 321a of the peripheral portion 321 via a sealing material F, and the contact surface 340a is provided with a wall portion 341 extending beyond the end surface 321a of the peripheral portion 321 at a position spaced more inwardly than the peripheral portion 321 along the inner periphery of the contact surface 340a.

[0050] In this configuration, since the wall portion 341 is provided along the inner periphery of the contact surface 340a of the inverter cover 34, when removing the sealing material F on the contact surface 340a with a tool or the like, the wall portion 341 functions as a baffle plate. Thereby, it is possible to prevent fragments of the sealing material F from entering the inside of the inverter cover 34 and avoid deterioration of the insulation performance of the inverter device 10. Further, since the wall portion 341 is disposed at a distance from the peripheral portion 321 of the housing 30, it functions as a guide when assembling the inverter cover 34 to the housing 30, improving workability.

[0051] Further, in the present embodiment, at least a part of the wall portion 341 includes an inscribed portion 342 that contacts the inner peripheral wall of the peripheral portion 321.

[0052] In this configuration, the gap at the fixed portion between the housing 30 and the inverter cover 34 can be reduced to define the position of the inverter device 10.

[0053] Further, in the present embodiment, the wall portion 341 includes the inscribed portion 342 so as to stand up from the contact surface 340a, and the contact surface 340a includes a groove portion 343 at the portion where the inscribed portion 342 stands up.

[0054] In this configuration, the fitting portion 342 comes into contact with the peripheral portion 321 to be in a press-fitted state and the fitting portion 342 receives stress. By forming the groove portion 343, stress concentration can be prevented.

[0055] Also, in the present embodiment, the inverter cover 34 has a rectangular shape in plan view, and the inverter device 10 has a bus bar 15 that exchanges power with the motor 20. The bus bar 15 is flat and is arranged in parallel so as to face the first short side S1 of the inverter cover 34. The fitting portion 342 has a first fitting portion 342a, a second fitting portion 342b, and a third fitting portion 342c. The first fitting portion 342a is provided to face the bus bar 15 at the first short side S1 of the inverter cover 34. The second fitting portion 342b and the third fitting portion 342c are provided on a pair of long sides (the first long side L1 and the second long side L2) of the inverter cover 34, respectively, and are provided to face each other on the extension line in the width direction of the bus bar 15.

[0056] In this configuration, by providing the second fitting portion 342b and the third fitting portion 342c on the first long side L1 and the second long side L2 so as to face each other, the inverter cover 34 is sandwiched in the short side direction by the peripheral portion 321 of the housing 30, and the position of the bus bar 15 in the plate direction is defined. Further, by providing the first fitting portion 342a to face the bus bar 15, the position of the bus bar 15 in the plate thickness direction is defined.

[0057] Also, in the present embodiment, a fourth fitting portion 342d is provided on the second short side S2 facing the first short side S1 of the inverter cover 34 so as to face the first fitting portion 342a.

[0058] In this configuration, by providing the first fitting portion 342a and the fourth fitting portion 342d on the first short side S1 and the second short side S2, respectively, the inverter cover 34 is sandwiched in the longitudinal direction by the peripheral portion 321 of the housing 30, and the position of the bus bar 15 in the plate thickness direction is defined more accurately.

[0059] Further, in the present embodiment, for the first short side S1 of the inverter cover 34, the width D1 of the seating surface where the contact surface 340a of the first short side S1 contacts the end surface 321a of the peripheral portion 321 is larger than the width D2 of the seating surface where the contact surfaces 340a of the other sides of the inverter cover 34 contact the end surface 321a of the peripheral portion 321.

[0060] In this configuration, when prying open the inverter cover 34, by inserting a tool into the first short side S1, the tool can be inserted deeper. As a result, it is no longer necessary to adjust the insertion depth of the tool, thus improving the working efficiency.

[0061] Further, in the present embodiment, the sealing material F is composed of FIPG and can closely adhere and fix the end surface 321a of the housing 30 and the contact surface 340a of the inverter cover 34, so that rainwater and dust can be prevented from entering the inverter device 10.

[0062] As described above, the embodiments of the present invention and their modifications have been explained. However, the above embodiments and modifications merely show some application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments.

[0063] Although the present embodiment has described a drive device for an electric vehicle that travels with the driving force of the motor 20, it is not limited thereto, and the present embodiment is similarly applicable to a hybrid vehicle that includes an engine and uses the rotation of the engine for power generation or driving.

[0064] Further, in the present embodiment, the sealing material F has been described as a liquid gasket (FIPG), but it is not limited thereto, and a solid gasket may also be used.

Description of Reference Numerals

[0065] 1: Drive device, 10: Inverter device, 15U: U-phase bus bar, 15V: V-phase bus bar, 15W: W-phase bus bar, 20: Motor, 30: Housing, 32: Recess, 34: Inverter cover, 35: Accommodation chamber, 321: Peripheral part, 321a: End face, 340: Side part, 340a: Contact surface, 341: Wall part, 342a: First inscribed part, 342b: Second inscribed part, 342c: Third inscribed part, 342d: Fourth inscribed part, 343: Groove part, L1: First long side, L2: Second long side, S1: First short side, S2: Second short side

Claims

1. A drive device comprising a rotating electrical machine and an inverter device disposed above the rotating electrical machine and configured to exchange power with the rotating electrical machine, wherein the rotating electrical machine is housed in a housing, and the housing has, at an upper portion thereof, a recess surrounded by a peripheral portion having a wall-like periphery, the inverter device has an inverter cover, electrical components are disposed on an inner surface of the inverter cover, and the inverter cover is fixed to the housing so that the electrical components are housed in the recess, the inverter cover includes a contact surface that contacts an end surface of the peripheral portion via a sealing material, the contact surface includes a wall portion that extends beyond the end surface of the peripheral portion at a position spaced from the inner peripheral side of the peripheral portion along an inner periphery of the contact surface, Drive device.

2. The drive device according to claim 1, wherein the wall portion includes an inscribed portion at least a part of which contacts an inner peripheral wall of the peripheral portion, Drive device.

3. The drive device according to claim 2, wherein the wall portion includes the inscribed portion so as to stand up from the contact surface, and the contact surface includes a groove portion at a site where the inscribed portion stands up, Drive device.

4. The drive device according to claim 2 or 3, wherein the inverter cover has a rectangular shape in a plan view, the inverter device has a bus bar configured to exchange power with the rotating electrical machine, the bus bar is flat and is arranged in parallel so as to face a first short side of the inverter cover, the inscribed portion includes a first inscribed portion, a second inscribed portion, and a third inscribed portion, the first inscribed portion is provided to face the bus bar at the first short side of the inverter cover, the second inscribed portion and the third inscribed portion are respectively provided on a pair of long sides of the inverter cover and are provided to face each other on an extension line in a width direction of the bus bar, Drive device.

5. The drive device according to claim 4, wherein a fourth inscribed portion is provided to face the first inscribed portion on a second short side of the inverter cover facing the first short side, Drive device.

6. The drive device according to claim 4, wherein a width of a seating surface where the contact surface of the first short side of the inverter cover contacts an end surface of the peripheral portion is larger than a width of a seating surface where contact surfaces of other sides of the inverter cover contact the end surface of the peripheral portion, Drive device.

7. The drive device according to claim 1, wherein the sealing material is composed of FIPG, Drive device.

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