unit

Abstract

[Problem] To provide a unit, the size of which can be reduced. [Solution] This unit comprises a capacitor, an electric circuit electrically connected to the capacitor, a rotating electric machine electrically connected to the electric circuit, and a shaft connected to the downstream of the rotating electric machine in a dynamic manner. In a first radial direction view, the shaft does not overlap the rotating electric machine. In the first radial direction view, one of the capacitor and the electric circuit overlaps the rotating electric machine. In the first radial direction view, the other of the capacitor and the electric circuit overlaps the shaft.

Description

[Technical Field]

[0001] The present invention relates to a unit. [Background technology]

[0002] Patent Document 1 discloses a unit equipped with an inverter. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-33113 Summary of the Invention [Problem to be solved by the invention]

[0004] In the unit described in Patent Document 1, the rotating electric machine overlaps with the shaft located between the rotating electric machine and the inverter in the horizontal direction, so the inverter cannot be placed close to the rotating electric machine, making it impossible to reduce the size of the unit.

[0005] The present invention has been made in view of the above problems, and has as its object to provide a unit that can be made smaller. [Means for solving the problem]

[0006] According to one aspect of the present invention, there is provided a power transmission system including: a capacitor; an electric circuit electrically connected to the capacitor; a rotating electric machine electrically connected to the electric circuit; and a shaft operatively connected downstream of the rotating electric machine, One of the capacitor and the electric circuit extends along a lateral direction perpendicular to an axial direction, the shaft overlaps with a rotor of the rotating electric machine in the lateral direction, Orthogonal to Vertical In this view, the shaft does not overlap with the rotating electric machine, Vertical In this view, one of the capacitor and the electric circuit overlaps with the rotating electric machine, VerticalIn this view, the capacitor and the other of the electric circuit are provided as a unit overlapping the shaft. [Effects of the Invention]

[0007] According to one aspect of the present invention, the unit can be made smaller. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing the unit according to this embodiment (with the fourth case removed). [Figure 2] FIG. 2 is a cross-sectional view showing the unit according to this embodiment. [Figure 3] FIG. 3 is a perspective view showing the fourth case. [Figure 4] FIG. 4 is a cross-sectional view showing a unit according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention (hereinafter simply referred to as the present embodiment) will be described with reference to the accompanying drawings.

[0010] First, a unit 1 according to this embodiment will be described with reference to Figures 1 to 3. Note that in this specification, the same elements are denoted by the same reference numerals throughout.

[0011] Fig. 1 is a perspective view showing unit 1 according to this embodiment (with fourth case 24 removed). Fig. 2 is a cross-sectional view showing unit 1 according to this embodiment. Fig. 3 is a perspective view showing fourth case 24.

[0012] The unit 1 shown in FIGS. 1 to 3 is used to drive the drive wheels (not shown) of a vehicle, but is not limited to this and may be used to drive an electrical appliance, for example. The unit 1 is also called a motor unit (a unit having at least a motor), a power transmission device (a device having at least a power transmission mechanism (e.g., a gear mechanism and / or a differential gear mechanism, etc.)), etc. Note that a device (unit) having a motor and a power transmission mechanism falls under the concepts of both a motor unit and a power transmission device. Specifically, the unit 1 includes a housing 2, a motor 3 as a rotating electric machine, a drive shaft 4 as a shaft, a reduction gear group 5 as a gear mechanism, and an inverter 6.

[0013] The housing 2 is a housing member that houses the motor 3, the drive shaft 4, the reduction gear group 5, and the inverter 6. The housing 2 is made up of one or more cases. Specifically, the housing 2 is made up of a first case 21, a second case 22, a third case 23 as case members (specifically, first case members), and a fourth case 24 as a case member (specifically, second case member).

[0014] The first case 21 is a 3-in-1 type. The 3-in-1 type means that a part of the motor case that houses the motor 3 and the drive shaft 4 and a part of the inverter case that houses the inverter 6 are integrally formed.

[0015] The first case 21 has a cylinder 211 that is open at at least one end, i.e., a front end, i.e., a front flange 212 that protrudes outward from the front end of the cylinder 211, a back flange 213 that protrudes outward from the other end, i.e., a rear ...

[0016] The cylinder 211 has an arcuate portion 211a whose one end is continuous with the protruding portion 214 and which houses a part of the motor 3 inside, and a flat portion 211b whose other end is continuous with the protruding portion 214 and which extends along the horizontal direction Y (see FIG. 2) as a second radial direction. The flat portion 211b and the drive shaft 4 are aligned in the vertical direction Z (see FIG. 2) as a first radial direction that intersects with (specifically, is perpendicular to) the horizontal direction Y.

[0017] The second case 22 is connected to the front end of the tube 211 of the first case 21. Specifically, the outer periphery of the second case 22 is connected to a front flange 212 by bolting. The second case 22 also supports both a front end serving as one end of a rotating shaft 31 (described later) of the motor 3 and a front end serving as one end of the drive shaft 4 via bearings (not shown).

[0018] The motor 3 is a rotating electric machine having a motor function and / or a generator function, and includes a rotating shaft 31 rotatably supported by the first case 21 and the second case 22 via bearings (not shown), a rotor 32 located on the outer periphery of the rotating shaft 31 and rotating integrally with the rotating shaft 31, and a stator 33 fixed to the inner periphery of the cylinder 211 so as to be located on the outer periphery of the rotor 32.

[0019] The drive shaft 4 rotates integrally with the drive wheels of the vehicle. The drive shaft 4 is operatively connected downstream of the motor 3 via a reduction gear group 5. This means that the motor 3 and the drive shaft 4 are connected so that power can be transmitted. The power input side is upstream, and the power output side is downstream. The drive shaft 4 is rotatably supported by the first case 21 and the second case 22 via bearings (not shown).

[0020] 2, the drive shaft 4 does not overlap with the motor 3 (specifically, the rotating shaft 31, the rotor 32, and the stator 33) when viewed in the first radial direction. That is, when viewed in the first radial direction, the drive shaft 4 is offset from the motor 3. That is, the drive shaft 4 and the motor 3 are not aligned in the vertical direction Z.

[0021] The third case 23 houses the reduction gear group 5. The third case 23 is configured as a bottomed cylinder that is open at one end (the front end) and closed at the other end (the rear end). The third case 23 is connected to the rear end of the cylinder 211. Specifically, the outer periphery of the front end of the third case 23 is connected to the back flange 213 by bolting.

[0022] The reduction gear group 5 has a portion that is offset from the motor 3 when viewed in the axial direction. That is, the reduction gear group 5 has a portion that does not overlap with the motor 3 when viewed in the axial direction. That is, the reduction gear group 5 has a portion that is not aligned with the motor 3 in the axial direction X.

[0023] The reduction gear group 5 is a power transmission mechanism that reduces the power of the motor 3 and transmits it to the drive shaft 4, and is made up of multiple gears. The reduction gear group 5 is operatively connected to the downstream side of the motor 3 and to the upstream side of the drive shaft 4.

[0024] 2 and 3, the fourth case 24 constitutes the other part of the inverter case. The inverter 6 is attached to the fourth case 24. The fourth case 24 is connected to a part of the outer periphery of the tube 211 (specifically, the arc portion 211a and the flat portion 211b) by bolting. A part of the inverter 6 is built into the housing area S formed by connecting the first case 21 and the fourth case 24.

[0025] The fourth case 24 has a first mounting portion 241 for mounting one of the capacitor 61 and the electrical circuit 62 of the inverter 6, which will be described later, and a second mounting portion 242 for mounting the other of the capacitor 61 and the electrical circuit 62 of the inverter 6, which will be described later.

[0026] In this embodiment, when the first case 21 and the fourth case 24 are connected, the first mounting portion 241 is a plate member extending along the lateral direction Y, and the second mounting portion 242 is a plate member inclined with respect to the lateral direction Y in a front view. Furthermore, the first mounting portion 241 and the second mounting portion 242 face the arc portion 211a and the flat portion 211b, respectively.

[0027] Furthermore, when the first case 21 and the fourth case 24 are connected, the fourth case 24 has a portion (specifically, the first mounting portion 241 and the second mounting portion 242) that overlaps with the third case 23 that constitutes the gear mechanism when viewed in the axial direction. That is, the fourth case 24 and the third case 23 are aligned in the axial direction X. This prevents the first mounting portion 241 and the second mounting portion 242 of the fourth case 24 from protruding from the third case 23 when viewed from the front, thereby enabling the entire unit 1 to be made smaller in the radial direction.

[0028] The inverter 6 is a controller for controlling the driving of the motor 3. The inverter 6 includes a capacitor 61, an electric circuit 62, a cooler 63, a power connector 64, and connection wiring 65.

[0029] The capacitor 61 (specifically, a smoothing capacitor) is an electronic component that stores and releases electricity. The capacitor 61 is attached to the rear surface of the first attachment portion 241 so as to extend along the lateral direction Y when viewed from the front.

[0030] The electric circuit 62 is electrically connected to the capacitor 61 and is also electrically connected to the motor 3 via connection wiring 65. The electric circuit 62 is attached to the rear surface of the second mounting portion 242. The electric circuit 62 also has a PWR board 621 as a board that is disposed so as to be inclined with respect to the lateral direction Y (i.e., the capacitor 61) when viewed from the front.

[0031] This allows the second mounting portion 242 to which the PWR board 621 is attached to also be arranged at an incline with respect to the horizontal direction Y, thereby making it possible to reduce the size of the unit 1 in the horizontal direction Y compared to a configuration in which the capacitor 61 and the PWR board 621 of the electric circuit 62 are arranged side by side in the horizontal direction Y. Furthermore, since it is easy to create inclined or stepped portions in the unit 1, the layout flexibility of the entire unit 1 can be improved.

[0032] The cooler 63 is a member for cooling the PWR board 621. The cooler 63 is attached to the surface of the second mounting portion 242. This makes it easier to arrange the cooling water passages of the cooler 63 compared to a configuration in which the cooler 63 is attached to the back surface of the second mounting portion 242. From the perspective of integrating the cooling water passages, it is preferable to also arrange a unit oil cooler on the surface of the second mounting portion 242.

[0033] 2, in this embodiment, as viewed in the first radial direction, the capacitor 61 overlaps with the motor 3, and as viewed in the first radial direction, the electric circuit 62 overlaps with the drive shaft 4 that is not aligned with the motor 3 in the vertical direction Z. That is, the capacitor 61 and the motor 3 are aligned in the vertical direction Z, and the electric circuit 62 and the drive shaft 4 that is not aligned with the motor 3 in the vertical direction Z are aligned in the vertical direction Z.

[0034] As a result, when viewed in the first radial direction, the drive shaft 4 is not positioned between the motor 3 and the inverter 6 (i.e., the drive shaft 4 is not positioned between the motor 3 and the inverter 6 when observed from the first radial direction), and the capacitor 61 and electrical circuit 62 of the inverter 6 are arranged close to the motor 3 and the drive shaft 4, respectively, so that the space radially around the motor 3 and the drive shaft 4 can be effectively utilized, thereby making it possible to reduce the size of the entire unit 1 in the vertical direction Z.

[0035] In this embodiment, in the first radial direction, the capacitor 61 and the electrical circuit 62 are arranged so as to overlap with the motor 3 and the drive shaft 4, respectively, but this is not limited to this and, for example, they may be arranged so as to overlap with the drive shaft 4 and the motor 3, respectively.

[0036] In this case, the electric circuit 62 is attached to the rear surface of the first attachment portion 241, and the capacitor 61 is attached to the rear surface of the second attachment portion 242.

[0037] When viewed in the first radial direction, the capacitor 61 and the electric circuit 62 are offset from the reduction gear group 5. That is, when viewed in the first radial direction, the capacitor 61 and the electric circuit 62 do not overlap with the reduction gear group 5. That is, the capacitor 61 and the electric circuit 62 are not aligned with the reduction gear group 5 in the vertical direction Z.

[0038] When viewed in the axial direction, the capacitor 61 and the electric circuit 62 have portions that overlap with the reduction gear group 5. That is, the capacitor 61 and the electric circuit 62 have portions that are aligned with the reduction gear group 5 in the axial direction X.

[0039] This makes it easier to create a layout that allows the unit 1 to be made smaller by effectively utilizing the space in the step formed by the motor 3 and the reduction gear group 5 and arranging the capacitor 61 and the electrical circuit 62 in the space in such step.

[0040] 2, the power connector 64 electrically connects a power source (not shown) and the capacitor 61. When viewed in the second radial direction, the capacitor 61 is disposed between the power connector 64 and the electric circuit 62. In other words, when observed from the lateral direction Y, the capacitor 61 is located between the power connector 64 and the electric circuit 62.

[0041] This allows the wiring arrangement to be simplified since it is possible to take electrical flow into consideration.

[0042] The power connector 64 also has a tip 641 that protrudes from the fourth case 24 in a direction away from the capacitor 61 (to the left in FIG. 2). As shown in FIG. 2, when viewed in the second radial direction, the protrusion 214 is disposed between the tip 641 of the power connector 64 and the capacitor 61. In other words, when observed from the lateral direction Y, the protrusion 214 is located between the tip 641 and the capacitor 61.

[0043] As a result, by offsetting the tip 641 of the power connector 64 from the protrusion 214 when viewed in the first radial direction, the effect of interference between the power connector 64 and the protrusion 214 when connecting the fourth case 24 to the first case 21 can be reduced.

[0044] The connection wiring 65 electrically connects the PWR board 621 of the electric circuit 62 to the motor 3. One end of the connection wiring 65 is connected to an end of the PWR board 621 that is separated from the capacitor 61, and the other end is connected to a connector of the motor 3.

[0045] (Variation) Next, a unit 1 according to a modified example will be described with reference to Fig. 4. Note that in this modified example, explanations of points that are the same as those in the above-described embodiment will be omitted, and differences from the above-described embodiment will be mainly described.

[0046] FIG. 4 is a cross-sectional view showing a unit 1 according to a modified example.

[0047] In the above-described embodiment, the electric circuit 62 is disposed so as to be inclined with respect to the capacitor 61, but this is not limiting and, for example, as shown in Fig. 4, the electric circuit 62 may be disposed so as to extend along the vertical direction Z. In this case, the second mounting portion 242 for mounting the electric circuit 62 is formed so as to extend along the horizontal direction Y from the first mounting portion 241 without being inclined with respect to the horizontal direction Y.

[0048] In this case, the drive shaft 4 overlaps with the rotation shaft 31 of the motor 3 when viewed in the second radial direction. That is, the drive shaft 4 and the rotation shaft 31 of the motor 3 are aligned in the horizontal direction Y. This allows a larger installation space in the vertical direction Z for the electric circuit 62 to be secured compared to the above-described embodiment, and therefore allows the entire unit 1 to be made smaller in the radial direction even when the electric circuit 62 is disposed to extend along the vertical direction Z.

[0049] Furthermore, in this modified example, as viewed in the second radial direction, the capacitor 61 is disposed between the power connector 64 and the electric circuit 62, as in the above-described embodiment, but the electric circuit 62 is disposed so as to extend along the vertical direction Z. Therefore, compared to the above-described embodiment, both the capacitor 61 and the power connector 64 can be disposed closer to the drive shaft 4 side (to the right in FIG. 4), and there is no need to have the tip 641 (see FIG. 2) of the power connector 64 protrude from the fourth case 24, as in the above-described embodiment. As a result, the entire power connector 64 can be housed within the fourth case 24, and the entire unit 1 can be made even more compact in the radial direction.

[0050] In a front view, the dimension of the electric circuit 62 in the vertical direction Z is larger than the dimension of the capacitor 61 in the horizontal direction Y. This improves the utilization rate of the housing area S formed by connecting the first case 21 and the fourth case 24.

[0051] The cooler 63 is disposed in the accommodation area S adjacent to the electric circuit 62 and extending along the vertical direction Z. When viewed in the second radial direction, the electric circuit 62 is disposed between the condenser 61 and the cooler 63.

[0052] (Action and effect) Next, the main effects of the embodiment and the modified example will be described.

[0053] (1) The unit 1 comprises a capacitor 61, an electrical circuit 62 electrically connected to the capacitor 61, a motor 3 (rotating electric machine) electrically connected to the electrical circuit 62, and a drive shaft 4 (shaft) dynamically connected downstream of the motor 3 (rotating electric machine), and when viewed in the first radial direction, the drive shaft 4 (shaft) does not overlap with the motor 3 (rotating electric machine), and when viewed in the first radial direction, the capacitor 61 overlaps with the motor 3 (rotating electric machine), and when viewed in the first radial direction, the electrical circuit 62 overlaps with the drive shaft 4 (shaft).

[0054] According to this configuration, when viewed in the first radial direction, the drive shaft 4 is not positioned between the motor 3 and the inverter 6, and the capacitor 61 and electrical circuit 62 of the inverter 6 are arranged close to the motor 3 and the drive shaft 4, respectively, so that the space radially around the motor 3 and the drive shaft 4 can be effectively utilized, thereby making it possible to reduce the size of the entire unit 1 in the vertical direction Z.

[0055] (2) The drive shaft 4 (shaft) is kinetically connected to the motor 3 (rotating electric machine) via a reduction gear (gear mechanism), and the reduction gear group 5 (gear mechanism) has a portion that is offset from the motor 3 (rotating electric machine) when viewed in the axial direction, and the capacitor 61 and the electrical circuit 62 are offset from the reduction gear group 5 (gear mechanism) when viewed in the first radial direction, and the capacitor 61 and the electrical circuit 62 have a portion that overlaps with the reduction gear group 5 (gear mechanism) when viewed in the axial direction.

[0056] According to this configuration, the space of the step formed by the motor 3 and the reduction gear group 5 is effectively utilized, and the capacitor 61 and the electrical circuit 62 are arranged in the space of such step, making it easier to adopt a layout that allows the unit 1 to be made smaller.

[0057] (3) The electric circuit 62 has a PWR board 621 (board), and the PWR board 621 (board) is disposed so as to be inclined relative to the capacitor 61.

[0058] According to this configuration, the second mounting portion 242 to which the PWR board 621 is attached can also be arranged at an incline with respect to the horizontal direction Y, so the unit 1 can be made smaller in size in the horizontal direction Y than in a configuration in which the capacitor 61 and the PWR board 621 of the electric circuit 62 are arranged side by side in the horizontal direction Y. In addition, since it is easy to create inclined or stepped portions in the unit 1, the layout flexibility of the entire unit 1 can be improved.

[0059] (4) The unit 1 further includes a power connector 64 electrically connected to the capacitor 61, and when viewed in a second radial direction intersecting the vertical direction Z (first radial direction), the capacitor 61 is arranged between the power connector 64 and the electrical circuit 62.

[0060] According to this configuration, the wiring arrangement can be simplified because it is possible to take into consideration the electrical flow.

[0061] (5) The unit 1 further includes a first case 21 (case member) that houses the motor 3 (rotating electric machine), and the first case 21 (case member) has a protrusion 214 that protrudes toward the outer periphery on the outer periphery of the motor 3 (rotating electric machine), and when viewed in the second radial direction, the protrusion 214 is positioned between the tip 641 of the power connector 64 and the capacitor 61.

[0062] According to this configuration, by offsetting the tip 641 of the power connector 64 from the protrusion 214 when viewed in the first radial direction, the effect of interference between the power connector 64 and the protrusion 214 can be reduced when connecting the fourth case 24 to the first case 21.

[0063] (6) When viewed in a second radial direction perpendicular to the vertical direction Z (first radial direction), the drive shaft 4 (shaft) overlaps with the rotating shaft 31 of the motor 3 (rotating electric machine), and the electrical circuit 62 is arranged to extend along the vertical direction Z (first radial direction).

[0064] According to this configuration, a larger installation space in the vertical direction Z for the electrical circuit 62 can be secured compared to the above-described embodiment, and therefore, even when the electrical circuit 62 is arranged to extend along the vertical direction Z, the entire unit 1 can be made smaller in the radial direction.

[0065] (7) In a front view, the dimension of the electric circuit 62 in the vertical direction Z (first radial direction) is larger than the dimension of the capacitor 61 in the horizontal direction Y (second radial direction).

[0066] According to this configuration, the utilization rate of the storage area S formed by connecting the first case 21 and the fourth case 24 can be improved.

[0067] Although the embodiments of the present invention have been described above, the above embodiments merely illustrate some of the application examples of the present invention, and it is not intended that the technical scope of the present invention be limited to the specific configurations of the above embodiments. [Explanation of symbols]

[0068] 1 unit 3 Motor (rotating electric machine) 4 shaft (drive shaft) 5 Reduction gear group (gear mechanism) 21 First case (case member) 61 Capacitor 62 Electrical Circuits 64 power connector 214 Protrusion 621 PWR board (board) 641 Tip

Claims

1. A capacitor, an electric circuit electrically connected to the capacitor; a rotating electric machine electrically connected to the electric circuit; a shaft operatively connected downstream of the rotating electric machine; one of the capacitor and the electric circuit extends along a lateral direction perpendicular to an axial direction; the shaft overlaps with the rotor of the rotating electric machine in the lateral direction, When viewed in a vertical direction perpendicular to the horizontal direction, the shaft does not overlap with the rotating electric machine, When viewed in the vertical direction, one of the capacitor and the electric circuit overlaps with the rotating electric machine, When viewed in the vertical direction, the other of the capacitor and the electric circuit overlaps with the shaft. unit.

2. the shaft is operatively connected to the rotating electric machine via a gear mechanism; the gear mechanism has a portion offset from the rotating electric machine when viewed in the axial direction, the capacitor and the electric circuit are offset from the gear mechanism when viewed in the vertical direction; When viewed in the axial direction, the capacitor and the electric circuit have portions that overlap with the gear mechanism. The unit of claim 1.

3. the electrical circuit has a substrate; The substrate is disposed so as to be inclined with respect to the capacitor. The unit of claim 1.

4. a power connector electrically connected to the capacitor; When viewed from the side, the capacitor is disposed between the power connector and the electric circuit. A unit according to any one of claims 1 to 3.

5. a case member that houses the rotating electric machine; the case member has a protrusion that protrudes toward the outer periphery of the rotating electric machine, When viewed from the side, the protrusion is disposed between the tip end of the power connector and the capacitor.

5. The unit of claim 4.

6. When viewed in the lateral direction, the shaft overlaps with a rotation axis of the rotating electric machine, the other of the capacitor and the electric circuit is arranged to extend along the vertical direction. A unit according to claim 1 or 2.

7. When viewed from the front, the dimension of the other of the capacitor and the electric circuit in the vertical direction is larger than the dimension of one of the capacitor and the electric circuit in the horizontal direction.

7. The unit of claim 6.

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