Vehicle drive device

Abstract

The present application relates to a vehicle drive device. Disclosed is a vehicle drive device (100) including: a housing (2); a rotary electric machine (1) provided in the housing and having power lines (1U, 1V, 1W) electrically connected to a power supply via a power converter (inverter IV); bus bars (7U, 7V, 7W) extending into the housing and engaged with the power lines; a hydraulic pump (electric hydraulic pump (72)); and an oil passage (92) having a jet hole (9221) for jetting oil discharged from the hydraulic pump toward at least one of the power lines and the bus bars.

Description

Technical Field

[0001] This invention relates to vehicle drive systems. Background Technology

[0002] It is known that a technology supplies lubricating oil from inside the housing to the junction box by lifting it using a differential gear mechanism. In this technology, the junction box is placed within the oil passage through which the lifted oil flows downwards due to gravity, thereby utilizing the oil passing through this passage to cool the junction box.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2007-159314

[0004] However, the component that holds a portion of the busbar connecting the power lines of the rotating electric machine to the power converter (here referred to as the "junction box") is supported by the housing of the rotating electric machine. Along the busbar path from the housing to the power converter, the junction box easily becomes hot, as the heat from the busbar is difficult to dissipate into the air. To prevent such overheating of the junction box, it is useful to reliably supply cooling oil to the power lines and busbars that contribute to the overheating.

[0005] Regarding this point, in the aforementioned prior art, since the junction box is enclosed within the oil passage, efficient heat dissipation from the junction box to the air cannot be expected (the volume within the passage is relatively small, and the air within the enclosed passage itself tends to overheat). Consequently, there is a tendency for an excessive amount of oil to be supplied to the junction box. Furthermore, it is difficult to create a passage that ensures a sufficient amount of oil flows into contact with the junction box, potentially leading to insufficient cooling of the junction box. Summary of the Invention

[0006] Therefore, in one aspect, the object of the present invention is to provide a method that makes it easy to supply sufficient amounts of oil to power lines and busbars.

[0007] According to one aspect of the present invention, a vehicle drive system is provided, comprising:

[0008] case;

[0009] A rotary motor, which is housed within the aforementioned housing and has a power line electrically connected to a power source via a power converter;

[0010] The busbar extends within the aforementioned housing and engages with the aforementioned power line;

[0011] Hydraulic pumps; and

[0012] The oil passage has an injection hole for injecting oil discharged from the hydraulic pump toward at least one of the power line and the busbar.

[0013] According to the present invention, sufficient oil can be easily supplied to the power line and busbar. Attached Figure Description

[0014] Figure 1 This is a diagram illustrating an example of the overall structure of a motor drive system.

[0015] Figure 2 This is a simplified diagram of the vehicle drive system in this embodiment.

[0016] Figure 3A It is a cross-sectional view along the axial direction of the vehicle's drive unit.

[0017] Figure 3B It is a simplified cross-sectional view perpendicular to the axis of the vehicle's drive unit.

[0018] Figure 3C This is a top view that briefly shows the inverter module housed in the third storage section.

[0019] Figure 4 This is a schematic diagram of a vehicle drive system.

[0020] Figure 5 It means Figure 3A The diagram illustrates an example of a branch oil circuit layout.

[0021] Figure 6 It is along Figure 5 A sectional view of line PP. Detailed Implementation

[0022] The embodiments will now be described in detail with reference to the accompanying drawings.

[0023] Here, before describing the vehicle drive device of this embodiment, a preferred electric vehicle motor drive system SM using the vehicle drive device of this embodiment will first be described. Furthermore, regarding the electric vehicle motor drive system SM... Figure 1 Unless otherwise specified, the term "connection" between various components in the description refers to "electrical connection".

[0024] Figure 1 This diagram illustrates an example of the overall structure of the motor drive system SM. The motor drive system SM is a system that drives the vehicle by using electricity from the high-voltage battery HB to power the rotary motor 1. Furthermore, the details of the method and structure of an electric vehicle are arbitrary, as long as it is a vehicle that uses electricity to drive the rotary motor 1. Electric vehicles generally include hybrid electric vehicles, where the power source is both an engine and the rotary motor 1, and electric vehicles, where the power source is solely the rotary motor 1. Hereinafter, unless otherwise specified, "vehicle" refers to a vehicle equipped with the motor drive system SM.

[0025] like Figure 1 As shown, the motor drive system SM includes a high-voltage battery HB (an example of a power source), a smoothing capacitor SC, an inverter IV (an example of a power converter), a rotating motor 1, and an inverter control device 6A.

[0026] A high-voltage battery (HB) is any energy storage device that stores electricity and outputs DC voltage. It can include capacitive components such as nickel-metal hydride batteries, lithium batteries, and double-layer capacitors. High-voltage batteries (HB) are typically batteries with a rated voltage exceeding 100V, such as 288V.

[0027] Inverter IV comprises U-phase, V-phase, and W-phase arms arranged in parallel between the positive and negative terminals. The U-phase arm contains a series connection of switching elements (IGBTs in this example) Q1 and Q2; the V-phase arm contains a series connection of switching elements (IGBTs in this example) Q3 and Q4; and the W-phase arm contains a series connection of switching elements (IGBTs in this example) Q5 and Q6. Additionally, diodes D11 to D16 are positioned between the collector and emitter of each switching element Q1 to Q6 to allow current to flow from the emitter side to the collector side. Furthermore, switching elements Q1 to Q6 can also be other switching elements besides IGBTs, such as MOSFETs (metal oxide semiconductor field-effect transistors).

[0028] The rotating motor 1 is, for example, a three-phase AC motor, in which one end of each of the three coils (U, V, and W phases) is connected at the neutral point. The other end of the U-phase coil is connected to the midpoint M1 of switching elements Q1 and Q2, the other end of the V-phase coil is connected to the midpoint M2 of switching elements Q3 and Q4, and the other end of the W-phase coil is connected to the midpoint M3 of switching elements Q5 and Q6. A smoothing capacitor SC is connected between the collector and the negative line of switching element Q1.

[0029] The inverter control unit 6A is connected to various sensors, including a current sensor (not shown) that detects the current flowing in the rotating motor 1. Based on sensor information from these sensors, the inverter control unit 6A controls the inverter IV. The inverter control unit 6A includes, for example, a CPU, ROM, and main memory (all not shown). The various functions of the inverter control unit 6A are implemented by the CPU reading control programs recorded in the ROM, etc., into the main memory and executing them. While the control method for the inverter IV is arbitrary, it basically involves the two switching elements Q1 and Q2 related to the U phase being turned on / off in opposite phases, the two switching elements Q3 and Q4 related to the V phase being turned on / off in opposite phases, and the two switching elements Q5 and Q6 related to the W phase being turned on / off in opposite phases.

[0030] In addition, Figure 1 In the example shown, the motor drive system SM has a single rotating motor 1, but it can also have additional motors (including generators). In this case, the additional motors (or multiple motors) can also be connected to the high-voltage battery HB in parallel with the rotating motor 1 and the inverter IV, along with the corresponding inverter. Furthermore, in Figure 1 In the example shown, although the motor drive system SM does not have a DC / DC converter, a DC / DC converter can be installed between the high-voltage battery HB and the inverter IV.

[0031] like Figure 1 As shown, a disconnection switch SW1 for cutting off the power supply from the high-voltage battery HB is provided between the high-voltage battery HB and the smoothing capacitor SC. The disconnection switch SW1 can also be a semiconductor switch, relay, or the like. The disconnection switch SW1 is normally in the ON state, but is switched OFF, for example, when a vehicle collision is detected. Furthermore, the switching of the disconnection switch SW1 between ON and OFF states can be achieved by the inverter control device 6A, or by other control devices.

[0032] Figure 2 This is a simplified diagram of the vehicle drive unit 100 in this embodiment. Figure 2 The vehicle drive unit 100 is shown in a simplified cross-section.

[0033] The vehicle drive unit 100 includes: a rotary motor 1, a housing 2, busbars 7U, 7V, and 7W, an oil supply unit 8, and an oil passage 92.

[0034] The housing 2 houses the rotary motor 1, etc. The housing 2 has an oil reservoir 90 for storing oil used to cool the rotary motor 1. That is, the housing 2 is configured such that its bottom is closed to store oil that falls due to gravity. Furthermore, the oil in the oil reservoir 90 can be stored within the housing 2, or used for lubrication of other drive mechanisms (e.g., differential gear mechanism 5), etc. Furthermore, in Figure 2In the middle, the cross-sectional shape of the shell 2 is rectangular, but its shape can vary depending on the layout of the surrounding components.

[0035] In this embodiment, as an example, the housing 2 includes an inverter housing portion 2a. The inverter housing portion 2a can be integrally formed with the housing 2. That is, the inverter housing portion 2a is integrally formed with the housing component in such a way that it is separated by a housing component (peripheral wall portion 21) that forms a space SP1 for housing the rotary motor 1.

[0036] The inverter module MJ is housed in the inverter housing section 2a. The inverter module MJ is a module that integrates the inverter IV, inverter control device 6A, etc., and may also include a smoothing capacitor SC. The inverter housing section 2a is preferably closed off from the outside by a cover member 25. That is, the inverter housing section 2a forms a closed space SP2, within which the inverter module MJ is arranged. This allows for appropriate implementation of EMC (Electromagnetic Compatibility) countermeasures for the inverter module MJ, and also reduces problems such as spatial resonance.

[0037] Busbars 7U, 7V, and 7W are arranged to pass through the housing component (peripheral wall 21) that divides the space SP1 and the enclosed space SP2, and extend within the space SP1 and the enclosed space SP2. Busbars 7U, 7V, and 7W are, for example, plate-shaped (e.g., sheet metal components), but can also be implemented using conductors with a circular cross-section. Busbars 7U, 7V, and 7W are respectively provided corresponding to the U-phase, V-phase, and W-phase, and are connected to the power lines 1U, 1V, and 1W of each phase from the rotating motor 1 (see also...). Figure 1 ) Joining. In Figure 2 The diagram schematically shows the joints 9U, 9V, and 9W between busbars 7U, 7V, and 7W and power lines 1U, 1V, and 1W. Furthermore, the joints between busbars 7U, 7V, and 7W and power lines 1U, 1V, and 1W can also be achieved, for example, by tightening bolts.

[0038] One end of buses 7U, 7V, and 7W connects to power lines 1U, 1V, and 1W inside housing 2, while the other end connects to the bus (not shown) on the inverter IV side inside inverter module MJ outside housing 2. Furthermore, buses 7U, 7V, and 7W can also extend to the midpoints M1, M2, and M3 of inverter IV (see reference). Figure 1 Alternatively, it can be electrically connected to the midpoints M1, M2, and M3 of inverter IV via other buses.

[0039] Busbars 7U, 7V, and 7W can also be sealed via a resin section (not shown) with the portions forming joints 9U, 9V, and 9W partially exposed. In this case, the resin section can be fixed to the housing 2 to retain busbars 7U, 7V, and 7W. Furthermore, in Figure 2 In this configuration, busbars 7U, 7V, and 7W are supported on the upper part of housing 2, but they can also be supported on the side of housing 2. Additionally, the resin portion can form a partition (not shown) between joints 9U, 9V, and 9W in a way that efficiently ensures creepage distance between busbars 7U, 7V, and 7W (or between joints 9U, 9V, and 9W).

[0040] In addition, the power lines 1U, 1V, and 1W from the rotating electric motor 1 are wound on the stator core 111 (in Figure 2 Not shown in the image, please refer to the diagram. Figure 3A Coil 112 (refer to) Figure 1 Alternatively, the power lines 1U, 1V, and 1W can also be formed as part of the coil 112 of the stator core 111. The power lines 1U, 1V, and 1W can also be in the form of coil wires (e.g., flat wires) identical to the coil 112 of the stator core 111. Alternatively, the power lines 1U, 1V, and 1W can also be in the form of plates (e.g., sheet metal parts) identical to the busbars 7U, 7V, and 7W, and can also be implemented using conductor wires with a circular cross-section. In addition, other busbars (intermediate busbars) can be sandwiched between the power lines 1U, 1V, and 1W and the busbars 7U, 7V, and 7W. In this case, the intermediate busbar can also be in the form of being sealed with resin and fixed to the housing 2.

[0041] Furthermore, the power lines 1U, 1V, and 1W extend to the outside of the motor housing 1B. In this case, the power lines 1U, 1V, and 1W, as well as the bus lines 7U, 7V, and 7W, preferably extend in the air within the housing 2. That is, the power lines 1U, 1V, and 1W, and the bus lines 7U, 7V, and 7W, are located above the oil reservoir 90. In this case, only a portion of the power lines 1U, 1V, and 1W, and the bus lines 7U, 7V, and 7W, can be located above the oil reservoir 90, or they can be located entirely above the oil reservoir 90. In this case, it is possible to prevent foreign matter that may mix into the oil stored in the oil reservoir 90 from adhering to the power lines 1U, 1V, and 1W, and the bus lines 7U, 7V, and 7W. In addition, it is possible to reduce the possibility of corrosion at the joints 9U, 9V, and 9W between the power lines 1U, 1V, and 1W and the bus lines 7U, 7V, and 7W.

[0042] The oil supply unit 8 includes an electric hydraulic pump 72 and an oil cooler 73. The electric hydraulic pump 72 has a motor, namely a pump motor 721, which is different from the rotary motor 1. When the electric hydraulic pump 72 is in operation, it draws in oil from the oil reservoir 90 and discharges the drawn-in oil through the oil cooler 73 toward the oil passage 92. Thus, the oil cooled by the oil cooler 73 is discharged into the oil passage 92. In addition, the oil cooler 73 may also be provided on the suction side relative to the electric hydraulic pump 72.

[0043] The electric hydraulic pump 72 preferably draws oil into the oil reservoir 90 via the filter 74. In this case, it is possible to prevent foreign matter that may be mixed with the oil from being discharged into the oil passage 92.

[0044] Oil circuit 92 is connected to electric hydraulic pump 72, which pumps the oil discharged from electric hydraulic pump 72. For example... Figure 2 As schematically shown, the oil passage 92 includes a cooling oil passage 921 and a second branch oil passage 922 (an example of a second oil passage section). Furthermore, the portion of the cooling oil passage 921 after the branch point with the second branch oil passage 922 is also referred to as a third branch oil passage 923 (an example of a third oil passage section). An example of a first oil passage section is formed by the portion of the cooling oil passage 921 upstream of the branch point with the second branch oil passage 922 (on the side of the electric hydraulic pump 72).

[0045] The cooling oil passage 921 supplies oil to the cooling target portion CP inside the rotary motor 1. The interior of the rotary motor 1 refers to the portion of the rotary motor 1 housed within the motor housing 1B. Furthermore, the motor housing 1B houses various structural components of the rotary motor 1 (described later). The cooling target portion CP is located inside the rotary motor 1. While the cooling target portion CP is arbitrary, it may include the coil end 112A, the rotor core 121 (and the permanent magnet 123 disposed on the rotor core 121), etc., as described later. Additionally, the housing 2 may also form part of the motor housing 1B.

[0046] The cooling oil passage 921 extends into the interior of the housing 2. Specifically, the cooling oil passage 921 extends into the interior of the rotary motor 1 within the housing 2. Furthermore, the cooling oil passage 921 may also have a portion extending outwards from the housing 2. The cooling oil passage 921 may also be formed inside the motor housing 1B within the rotary motor 1, or it may be formed by other specific structural components of the rotary motor 1 (e.g., rotor shaft 122, etc.). Additionally, the cooling oil passage 921 may also be formed outside the rotary motor 1 by a tubular component, or it may be formed in the housing 2 and / or other housings.

[0047] The second branch oil passage 922 is connected to the cooling oil passage 921. Furthermore, the second branch oil passage 922 can also be connected to the cooling oil passage 921 in any manner, as long as it supplies a portion of the oil discharged from the electric hydraulic pump 72. For example, as... Figure 2 As shown, the second branch oil passage 922 can also be connected to the cooling oil passage 921 in a manner that branches off from the section of the cooling oil passage 921 located inside the rotary motor 1 on the upstream side (the side closest to the oil supply section 8). Alternatively, although not shown, the second branch oil passage 922 can also be connected to the cooling oil passage 921 in a manner that branches off from the section of the cooling oil passage 921 located inside the rotary motor 1, or it can be connected to the cooling oil passage 921 continuously on the downstream side of that section.

[0048] The second branch oil passage 922 supplies oil to at least one of the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W. For example, the second branch oil passage 922 may supply oil only to the power lines 1U, 1V, 1W, or only to the busbars 7U, 7V, 7W, or to both power lines 1U, 1V, 1W and busbars 7U, 7V, 7W. The power lines 1U, 1V, 1W and busbars 7U, 7V, 7W are connected on a phase-by-phase basis, and heat conduction is performed on a phase-by-phase basis. Therefore, even if only one of the power lines 1U, 1V, 1W and busbars 7U, 7V, 7W is cooled, both can be cooled. However, it is preferable that the second branch oil passage 922 supplies oil to both power lines 1U, 1V, 1W and busbars 7U, 7V, 7W. For example, the second branch oil circuit 922 can also supply oil to the junctions 9U, 9V, and 9W of the power lines 1U, 1V, 1W and the bus lines 7U, 7V, 7W.

[0049] The second branch oil passage 922 extends into the interior of the housing 2. The second branch oil passage 922 also extends outwards from the rotary motor 1. The second branch oil passage 922 may be formed by a tubular component, similar to the cooling oil passage 921, or it may be formed within the housing 2 and / or other housings. Alternatively, the second branch oil passage 922 may be implemented through a combination of an oil passage formed by a tubular component and an oil passage formed within the housing 2 and / or other housings.

[0050] According to this embodiment, the oil discharged from the oil supply unit 8 is supplied not only to the cooling target part CP of the rotary motor 1 via the cooling oil passage 921, but also to the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W via the second branch oil passage 922. Therefore, the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W can be effectively cooled using the oil supplied to the cooling target part CP of the rotary motor 1.

[0051] However, the power lines 1U, 1V, 1W and the bus lines 7U, 7V, 7W form the path for a large current flowing between the high-voltage battery HB and the rotating motor 1, thus easily becoming relatively hot. If the power lines 1U, 1V, 1W and the bus lines 7U, 7V, 7W become relatively hot, the ambient air temperature inside the housing 2 increases, which may necessitate improving the cooling performance for the rotating motor 1, etc. Furthermore, if the power lines 1U, 1V, 1W and the bus lines 7U, 7V, 7W become relatively hot, heat is transferred to the inverter module MJ, which may also necessitate improving the cooling performance for the inverter module MJ. Especially when the inverter housing portion 2a containing the inverter module MJ forms a closed space SP2, the inverter module MJ is not exposed to the outside air, making it difficult for the heat from the inverter module MJ to dissipate into the air. Furthermore, since the inverter housing 2a is integrally formed with the housing 2, the buses 7U, 7V, and 7W are not exposed to the outside air, making it difficult for the heat from the buses 7U, 7V, and 7W to dissipate into the air. Under such circumstances, the need to improve the cooling performance of the buses 7U, 7V, 7W, and the inverter module MJ becomes increasingly apparent.

[0052] In this respect, according to this embodiment, as described above, since the power lines 1U, 1V, 1W and the bus lines 7U, 7V, 7W can be cooled by oil supplied via the second branch oil passage 922, the ambient air temperature inside the housing 2 can be effectively reduced. As a result, the cooling function of the rotating motor 1, etc., can be prevented from becoming excessive. In addition, since the inverter module MJ can dissipate heat to the oil via the bus lines 7U, 7V, 7W, the cooling function on the inverter module MJ side can be simplified / miniaturized. For example, the size of the flow path (not shown) for cooling water provided to the inverter IV can also be reduced. Thus, according to this embodiment, efficient oil cooling of the entire vehicle drive unit 100 can be achieved using oil from the electric hydraulic pump 72.

[0053] Furthermore, according to this embodiment, the oil used for cooling the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W, as described above, is oil cooled by the oil cooler 73. Therefore, it can efficiently cool the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W together with the cooling target part CP inside the rotary motor 1. Thus, according to this embodiment, even when the amount of oil used for cooling the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W is relatively small, the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W can be cooled in the desired manner. In other words, an amount of oil sufficient for desired cooling can be supplied to the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W together with the cooling target part CP inside the rotary motor 1 without causing excessive discharge from the electric hydraulic pump 72.

[0054] Here, the internal cooling target part CP (especially stator 11) of the rotary motor 1 and the power lines 1U, 1V, 1W and busbars 7U, 7V, 7W heat up at the same time. In this embodiment, the second branch oil passage 922 branches off from the cooling oil passage 921 used to cool the cooling target part CP, so the power lines 1U, 1V, 1W and busbars 7U, 7V, 7W can be efficiently cooled by the oil flowing in the second branch oil passage 922. Furthermore, by setting the hydraulic source to an electric hydraulic pump 72, the electric hydraulic pump 72 is turned on when the cooling target part CP and the power lines 1U, 1V, 1W and busbars 7U, 7V, 7W heat up significantly, and turned off when the heat is relatively low, thus achieving efficient cooling. Thus, according to this embodiment, oil from a shared electric hydraulic pump 72 can be used to efficiently cool two or more objects that generate heat at the same time (cooling object parts CP and power lines 1U, 1V, 1W, and busbars 7U, 7V, 7W). For example, if two objects generate heat at different times, it is possible that one object has a higher cooling requirement while the other has a lower cooling requirement. In this situation, if the electric hydraulic pump 72 is turned on based on the higher cooling requirement of one object, it results in inefficiency by wastefully cooling the other object. On the other hand, if the electric hydraulic pump 72 is turned off based on the lower cooling requirement of the other object, it results in the undesirable situation of one object overheating. According to this embodiment, such inefficiency and undesirable situations can be prevented.

[0055] Furthermore, according to this embodiment, the oil supplied to the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W is oil at the same temperature as the oil used to cool the target part CP, rather than oil that has been cooled after cooling the target part CP. Therefore, the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W can be cooled efficiently.

[0056] Furthermore, if the amount of oil discharged from the electric hydraulic pump 72 of the oil supply section 8 for cooling the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W is too large relative to the amount of oil used for cooling the internal cooling target part CP of the rotating motor 1, then the internal cooling target part CP of the rotating motor 1 cannot be properly cooled. Therefore, when the amount of oil discharged from the oil supply section 8 is set to "100", the amount of oil used for cooling the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W is preferably "30" or less (i.e., 30% or less), and more preferably "10" or less (i.e., 10% or less). Moreover, such adjustment of the oil amount (distribution adjustment) can be achieved by adjusting the ratio (=α1 / α0) of the total opening area α1 of the openings involved in the oil used for cooling the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W when the total opening area of ​​all the openings of the oil passage 92 is set to α0. That is, when the total area of ​​the opening holes involved in the oil used for cooling the internal cooling part CP of the rotating motor 1 is set to α2, α1+α2=α0, α1 / α0=0.1, thereby enabling a 10% allocation for cooling of the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W.

[0057] However, in this embodiment, as an example, since oil is sprayed toward the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W, foreign matter in the conductors may be mixed into the oil, potentially negatively affecting the electrical characteristics of the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W. In this regard, in this embodiment, as an example, as described above, since oil is supplied to the electric hydraulic pump 72 via the filter 74, the possibility of foreign matter being mixed into the oil supplied to the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W can be reduced. As a result, the possibility of negatively affecting the electrical characteristics of the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W due to foreign matter possibly mixed into the oil (e.g., the possibility of phase-to-phase continuity due to foreign matter in the conductors) can be reduced.

[0058] Next, refer to Figures 3A to 6 As a more specific embodiment, an example of the mechanical structure of the vehicle drive unit 100 and the flow of oil in the vehicle drive unit 100 will be described.

[0059] Figure 3A It is a cross-sectional view along the axial direction of the vehicle drive unit 100. Figure 3B It is a simplified cross-sectional view perpendicular to the axis L of the vehicle drive unit 100. Figure 3C This is a top view that briefly shows the inverter module MJ housed in the third storage section 2C. Figure 4 This is a schematic diagram of a vehicle drive unit 100.

[0060] Figure 5 yes Figure 3A The diagram illustrating the second branch oil passage 922 is a top view of the first sidewall portion 22 viewed along the axial direction. Figure 6 It is along Figure 5 A sectional view of line PP. In Figure 6 In the middle, it is briefly shown together in Figure 5 Inverter module MJ, not shown. Furthermore, in Figure 3B In the diagram, the outlines of the input gear 32 and the first reverse gear 42 are shown by dashed lines, while the outlines of the differential input gear 51 and the second reverse gear 43 are shown by single-dot dashed lines.

[0061] like Figure 3A as well as Figure 4 As shown, the vehicle drive unit 100 includes a rotary motor 1 that serves as a driving force source for the wheel W, and a drive transmission mechanism 10 disposed in a power transmission path P connecting the rotary motor 1 and the wheel W. In this embodiment, as an example, the rotary motor 1 and the drive transmission mechanism 10 are housed in a housing 2. Furthermore, in this embodiment, as an example, the drive transmission mechanism 10 includes an input component 3, a reversing gear mechanism 4, a differential gear mechanism 5, a first output component 61, and a second output component 62.

[0062] A rotary motor 1 is mounted on a first shaft A1, which serves as its rotation axis. In this embodiment, as an example, an input component 3 is also mounted on the first shaft A1. A reversing gear mechanism 4 is mounted on a second shaft A2, which serves as its rotation axis. A differential gear mechanism 5 is mounted on a third shaft A3, which serves as its rotation axis. In this embodiment, as an example, a first output component 61 and a second output component 62 are also mounted on the third shaft A3. The first shaft A1, the second shaft A2, and the third shaft A3 are different imaginary axes and are parallel to each other.

[0063] In the following description, the direction parallel to the aforementioned axes A1 to A3 is defined as the "axial direction L" of the vehicle drive unit 100. Furthermore, along the axial direction L, the side on which the rotary motor 1 is positioned relative to the input component 3 is designated as the "first axial direction L1," and the opposite side is designated as the "second axial direction L2." Additionally, the direction orthogonal to each of the aforementioned first axis A1, second axis A2, and third axis A3 is designated as the "radial direction R" based on each axis. Moreover, when it is not necessary to distinguish which axis is used as the reference, or when it is clear which axis is used as the reference, it is sometimes simply referred to as "radial direction R."

[0064] like Figure 3AAs shown, in this embodiment, as an example, the housing 2 includes a peripheral wall portion 21, a first side wall portion 22, a second side wall portion 23, and a partition wall portion 24. The peripheral wall portion 21 is formed into a cylindrical shape surrounding the outer side of the rotary motor 1 and the drive transmission mechanism 10 in a radial direction R. The first side wall portion 22 and the second side wall portion 23 are formed to extend along the radial direction R. The first side wall portion 22 is fixed to the end of the peripheral wall portion 21 in a manner that closes the opening of the peripheral wall portion 21 in a axial direction L1. The second side wall portion 23 is fixed to the end of the peripheral wall portion 21 in a manner that closes the opening of the peripheral wall portion 21 in a axial direction L2.

[0065] The partition wall 24 is formed to divide the space inside the radial R of the peripheral wall 21 along the axial direction L, that is, the space between the first side wall 22 and the second side wall 23. In this embodiment, as an example, a rotary motor 1 is disposed between the partition wall 24 and the first side wall 22. Moreover, a drive transmission mechanism 10 is disposed between the partition wall 24 and the second side wall 23. In addition, the partition wall 24 may also form part of the motor housing 1B.

[0066] The rotating electric machine 1 has a stator 11 and a rotor 12. Furthermore, the term "rotating electric machine" is used as a concept encompassing a motor (electric motor), an engine (generator), and a motor / engine that performs the functions of both as needed.

[0067] The stator 11 has a stator core 111 fixed to a non-rotating component (e.g., housing 2). The rotor 12 has a rotor core 121 rotatable relative to the stator 11 (stator core 111) and a rotor shaft 122 connected to the rotor core 121 in a manner that rotates integrally with the rotor core 121. In this embodiment, as an example, the rotary motor 1 is a rotary excitation type rotary motor. Therefore, the coil 112 is wound on the stator core 111 in such a way that coil ends 112A protrude from the stator core 111 to both sides (axial first side L1 and axial second side L2) in the axial direction L. Moreover, a permanent magnet 123 is provided on the rotor core 121. In addition, in this embodiment, as an example, the rotary motor 1 is an inner rotor type rotary motor, so the rotor core 121 is arranged radially inside the stator core 111. Moreover, the rotor shaft 122 is connected to the inner circumferential surface of the rotor core 121.

[0068] Rotor shaft 122 rotates about a first axis A1. Rotor shaft 122 is formed as a cylindrical shape extending along the axial direction L. In this embodiment, as an example, rotor shaft 122 is supported by a first rotor bearing B1a and a second rotor bearing B1b to be rotatable relative to housing 2. Specifically, the end of rotor shaft 122 on the axial first side L1 is supported by the first rotor bearing B1a to be rotatable relative to the first sidewall portion 22 of housing 2. Furthermore, the end of rotor shaft 122 on the axial second side L2 is supported by the second rotor bearing B1b to be rotatable relative to the partition wall portion 24. Additionally, in this embodiment, as an example, both end faces of rotor shaft 122 on the axial direction L are open. Moreover, the internal space of rotor shaft 122 functions as a rotor shaft oil passage 122a for oil flow.

[0069] Input component 3 is the input member of drive transmission mechanism 10. Input component 3 has input shaft 31 and input gear 32.

[0070] The input shaft 31 is a rotating component that rotates about a first axis A1. The input shaft 31 is formed to extend along the axial direction L. In this embodiment, as an example, the input shaft 31 is inserted into a through hole that passes through the partition 24 along the axial direction L. Moreover, the end of the input shaft 31 on the first axial side L1 is connected to the end of the rotor shaft 122 on the second axial side L2. In the illustrated example, the end of the input shaft 31 on the first axial side L1 is inserted into the end of the rotor shaft 122 on the second axial side L2, with the input shaft 31 located inside the rotor shaft 122 on the radial direction R, and the ends are connected to each other by spline engagement.

[0071] In this embodiment, as an example, the input shaft 31 is supported by a first input bearing B3a and a second input bearing B3b to be rotatable relative to the housing 2. Specifically, the portion of the input shaft 31 that is closer to the first axial side L1 than the center of the axial direction L and closer to the second axial side L2 than the portion connecting to the rotor shaft 122 is supported by the first input bearing B3a to be rotatable relative to the partition wall portion 24. Furthermore, the end of the input shaft 31 on the second axial side L2 is supported by the second input bearing B3b to be rotatable relative to the second sidewall portion 23.

[0072] Furthermore, in this embodiment, as an example, the input shaft 31 is formed into a cylindrical shape with its end face open on its axial second side L2. Moreover, the internal space of the input shaft 31 functions as an input shaft oil passage 31a for the flow of oil from the mechanical hydraulic pump 71.

[0073] The input gear 32 is a gear that transmits the driving force from the rotary motor 1 to the reversing gear mechanism 4. The input gear 32 is connected to the input shaft 31 in a manner that allows it to rotate integrally with the input shaft 31. In this embodiment, as an example, the input gear 32 is integrally formed with the input shaft 31. Furthermore, in this embodiment, as an example, the input gear 32 is disposed between the first input bearing B3a and the second input bearing B3b.

[0074] The reversing gear mechanism 4 is positioned in the power transmission path P between the input component 3 and the differential gear mechanism 5. The reversing gear mechanism 4 has a countershaft 41, a first reversing gear 42, and a second reversing gear 43.

[0075] The secondary shaft 41 is a rotating component that rotates about the second axis A2. The secondary shaft 41 is formed to extend along the axial direction L. In this embodiment, as an example, the secondary shaft 41 is supported by a first secondary bearing B4a and a second secondary bearing B4b to be rotatable relative to the housing 2. Specifically, the axial first side L1 end of the secondary shaft 41 is supported by the first secondary bearing B4a to be rotatable relative to the partition wall portion 24. Furthermore, the axial second side L2 end of the secondary shaft 41 is supported by the second secondary bearing B4b to be rotatable relative to the second sidewall portion 23.

[0076] In this embodiment, as an example, the secondary shaft 41 is formed into a cylindrical shape with both ends open along its axial direction L. Furthermore, the internal space of the secondary shaft 41 functions as a secondary shaft oil passage 41a for the flow of oil from the mechanical hydraulic pump 71.

[0077] The first reverse gear 42 is the input component of the reverse gear mechanism 4. The first reverse gear 42 meshes with the input gear 32 of the input component 3. The first reverse gear 42 is connected to the secondary shaft 41 in a manner that it rotates integrally with the secondary shaft 41. In this embodiment, as an example, the first reverse gear 42 is connected to the secondary shaft 41 via a spline engagement. Additionally, in this embodiment, as an example, such as... Figure 3A As shown, the first reverse gear 42 is disposed between the first secondary bearing B4a and the second secondary bearing B4b and is positioned axially on the first side L1 further than the second reverse gear 43. However, in a modified example, the first reverse gear 42 may also be disposed between the first secondary bearing B4a and the second secondary bearing B4b and positioned axially on the second side L2 further than the second reverse gear 43 (see reference). Figure 4 ).

[0078] The second reverse gear 43 is the output component of the reverse gear mechanism 4. In this embodiment, as an example, the second reverse gear 43 is formed with a diameter smaller than that of the first reverse gear 42. The second reverse gear 43 is connected to the secondary shaft 41 in a manner that allows it to rotate integrally with the secondary shaft 41. In this embodiment, as an example, the second reverse gear 43 is integrally formed with the secondary shaft 41.

[0079] The differential gear mechanism 5 distributes the driving force transmitted from the rotary motor 1 to the first output component 61 and the second output component 62. The differential gear mechanism 5 includes a differential input gear 51, a differential housing 52, a pinion shaft 53, a pair of pinions 54, a first side gear 55, and a second side gear 56. In this embodiment, as an example, the pair of pinions 54, the first side gear 55, and the second side gear 56 are all bevel gears.

[0080] The differential input gear 51 is the input component of the differential gear mechanism 5. The differential input gear 51 meshes with the second reverse gear 43 of the reverse gear mechanism 4. The differential input gear 51 is connected to the differential housing 52 in a manner that allows it to rotate integrally with the differential housing 52. In this embodiment, as an example, a rotary motor 1 is arranged on the first axial side L1 relative to the differential input gear 51.

[0081] The differential housing 52 is a rotating component that rotates about a third axis A3. In this embodiment, as an example, the differential housing 52 is supported by a first differential bearing B5a and a second differential bearing B5b to be rotatable relative to the housing 2. Specifically, the axial first side L1 end of the differential housing 52 is supported by the first differential bearing B5a to be rotatable relative to the partition wall portion 24. Moreover, the axial second side L2 end of the differential housing 52 is supported by the second differential bearing B5b to be rotatable relative to the second sidewall portion 23.

[0082] The differential housing 52 is a hollow component. Inside the differential housing 52 are housed a pinion shaft 53, a pair of pinions 54, a first side gear 55, and a second side gear 56.

[0083] The pinion shaft 53 extends radially R with reference to the third axis A3. The pinion shaft 53 is inserted into a pair of pinions 54, supporting them for rotation. The pinion shaft 53 is configured to pass through the differential housing 52. The pinion shaft 53 is engaged with the differential housing 52, for example, by a locking member (not shown) in the form of a rod-shaped pin, and rotates integrally with the differential housing 52.

[0084] A pair of pinions 54 are mounted on a pinion shaft 53, positioned at intervals from each other along a radial direction R with the third axis A3 as the reference. The pair of pinions 54 are configured to be able to rotate (rotate) about the pinion shaft 53 and to rotate (revolve) about the third axis A3.

[0085] The first side gear 55 and the second side gear 56 are distributed rotating members in the differential gear mechanism 5. The first side gear 55 and the second side gear 56 are arranged opposite each other, spaced apart axially by a distance L and sandwiching the pinion shaft 53. The first side gear 55 is positioned axially a first side L1 closer to the second side gear 56. The first side gear 55 and the second side gear 56 are configured to rotate circumferentially within the internal space of the differential housing 52. The first side gear 55 and the second side gear 56 mesh with a pair of pinions 54. The first side gear 55 is integrally rotatably connected to the first output member 61. Conversely, the second side gear 56 is integrally rotatably connected to the second output member 62.

[0086] The first output component 61 and the second output component 62 are respectively connected to the wheel W. The first output component 61 and the second output component 62 transmit the driving force distributed by the differential gear mechanism 5 to the wheel W.

[0087] In this embodiment, as an example, the first output component 61 includes a first axle 611 and a relay component 612. The first axle 611 is driven to a wheel W on the first axial side L1. The relay component 612 is a rotating component that rotates about a third axis A3. The relay component 612 is a shaft component extending along the axial direction L. The relay component 612 is inserted into a through hole that passes through the partition portion 24 along the axial direction L. The relay component 612 is supported by an output bearing B6 so that it can rotate relative to the first side wall portion 22 of the housing 2. The end of the relay component 612 on the first axial side L1 protrudes to the outside of the housing 2 through the through hole that passes through the first side wall portion 22 of the housing 2 along the axial direction L. The end of the relay component 612 on the first axial side L1 is integrally rotatably connected to the first axle 611. In this embodiment, as an example, the relay component 612 is formed into a cylindrical shape with its end face open on the first axial side L1. Furthermore, corresponding splines are formed on the inner circumferential surface of the relay component 612 and the outer circumferential surface of the axial second side L2 end of the first axle 611, respectively. These splines engage with each other, connecting the relay component 612 and the first axle 611 in a rotatable manner. On the other hand, the axial second side L2 end of the relay component 612 is connected to the first side gear 55 of the differential gear mechanism 5 in a rotatable manner. In this embodiment, as an example, corresponding splines are formed on the outer circumferential surface of the axial second side L2 end of the relay component 612 and the inner circumferential surface of the first side gear 55, respectively. These splines engage with each other, connecting the relay component 612 and the first side gear 55 in a rotatable manner.

[0088] In this embodiment, as an example, the second output component 62 includes a second axle 621. The second axle 621 is driven to connect with a wheel W on the axial second side L2. The second axle 621 is connected to the second side gear 56 in a rotatable manner. In this embodiment, as an example, corresponding splines are formed on the outer peripheral surface of the end of the second axle 621 on the axial first side L1 and on the inner peripheral surface of the second side gear 56, respectively. These splines engage with each other to connect the second axle 621 and the second side gear 56 in a rotatable manner.

[0089] Here, refer to Figure 3B as well as Figure 3C The positional relationships of the rotating electric motor 1, input component 3, reversing gear mechanism 4, differential gear mechanism 5, and inverter module MJ are explained. Furthermore, in... Figure 3B as well as Figure 3C In the description, the vertical direction of the vehicle drive unit 100 when mounted in a vehicle is defined as the "vertical direction V". Furthermore, the upper position of the vertical direction V is indicated by "up", such as above or upper end, and the lower position of the vertical direction V is indicated by "down", such as below or lower end. Additionally, the direction orthogonal to the axis L when viewed along the vertical direction V is defined as the "depth direction D". Moreover, in the depth direction D, the side with respect to the rotary motor 1 that houses the differential gear mechanism 5 is designated as "front side D1", and the opposite side is designated as "rear side D2".

[0090] like Figure 3B As shown, the shaft (A2) of the reversing gear mechanism 4 is positioned slightly below both the shaft (A1) of the rotary motor 1 and the shaft (A3) of the differential gear mechanism 5. Figure 3B In the example shown, the first axis A1, the second axis A2, and the third axis A3 are arranged from above in the order of first axis A1, third axis A3, and second axis A2.

[0091] The inverter module MJ is positioned axially on the first side L1 relative to the differential input gear 51 of the differential gear mechanism 5. Furthermore, the inverter module MJ is positioned above the axis (A3) of the differential gear mechanism 5. Moreover, as... Figure 3B As shown, the inverter module MJ, viewed along the axial direction L, is positioned overlapping with the differential input gear 51. Here, regarding the configuration of the two components, "overlapping when viewed along a specific direction" means that, when an imaginary line parallel to that specific direction is moved in directions orthogonal to that imaginary line, the area where the imaginary line intersects both components exists at least partially. Furthermore, in Figure 3B In the diagram, the outlines of the input gear 32 and the first reverse gear 42 are shown by dashed lines, while the outlines of the differential input gear 51 and the second reverse gear 43 are shown by single-dot dashed lines.

[0092] A portion of the inverter module MJ is positioned axially L between the rotary motor 1 and the differential input gear 51. Furthermore, a portion of the inverter module MJ, viewed vertically V, is positioned overlapping with the reversing gear mechanism 4. Additionally, as... Figure 3B As shown, the inverter module MJ, viewed along the axial direction L, can be configured to overlap with the rotating motor 1.

[0093] like Figure 3B As shown, in this embodiment, as an example, the lowermost end of the reversing gear mechanism 4, i.e., the lower end 4a of the reversing gear, is positioned at the same position or above the lowermost end of the differential gear mechanism 5, i.e., the lower end 5a of the differential gear, in the vertical direction V. In the illustrated example, the lower end 4a of the reversing gear is positioned above the lower end 5a of the differential gear. In this embodiment, as an example, the lower end 4a of the reversing gear is the lower end of the first reversing gear 42. Furthermore, the lower end 5a of the differential gear is the lower end of the differential input gear 51.

[0094] In this embodiment, as an example, the uppermost end of the inverter module MJ, i.e., the upper end 7a of the module, is positioned at the same position or below the uppermost end of the rotary motor 1, i.e., the upper end 1a of the rotary motor, in the vertical direction V. In the illustrated example, the upper end 7a of the module and the upper end 1a of the rotary motor are positioned at the same position in the vertical direction V. In this embodiment, as an example, the upper end 1a of the rotary motor is the upper end of the outer peripheral surface of the stator core 111.

[0095] like Figure 3B As shown, in this embodiment, as an example, the housing 2 forms a space for housing the rotary motor 1 (and...). Figure 2 The space SP1 corresponds to the first storage section 2A, the second storage section 2B which stores the differential gear mechanism 5, and the third storage section 2C which stores the inverter module MJ. The third storage section 2C is a space that is not connected to the first storage section 2A and the second storage section 2B, forming a space that is closed relative to the outside (with...). Figure 2 (Corresponding to the enclosed space SP2). The third storage section 2C can be formed by the peripheral wall section 21. The third storage section 2C has an opening at the top so that the inverter module MJ can be stored from above. This opening is provided by the cover member (see reference) when the inverter module MJ is stored in the third storage section 2C. Figure 2 The cover component 25) is closed.

[0096] In this embodiment, as an example, the inverter module MJ is disposed below the uppermost end of the first storage portion 2A (i.e., the first uppermost end 2Aa) and the uppermost end of the second storage portion 2B (i.e., the second uppermost end 2Ba). In the illustrated example, the first uppermost end 2Aa is located above the second uppermost end 2Ba. Furthermore, the inverter module MJ is disposed below the first uppermost end 2Aa. Additionally, in this embodiment, as an example, the inverter module MJ is disposed between the outermost end of the first storage portion 2A (i.e., the first outermost depth end 2Ab) and the outermost end of the second storage portion 2B (i.e., the second outermost depth end 2Bb) in the depth direction D. In other words, the inverter module MJ is disposed between the outermost ends of the first storage portion 2A and the second storage portion 2B in the depth direction D. In the illustrated example, the first outermost depth end 2Ab is the outermost end of the rear side D2 of the first storage portion 2A. In addition, the second outermost depth end 2Bb is the outermost end of the front side D1 of the second storage part 2B.

[0097] In addition, such as Figure 3C As shown, in this embodiment, as an example, the inverter module MJ is disposed along the axial direction L between the outermost end of the first housing portion 2A (i.e., the first outermost shaft end 2Ac) and the outermost end of the second housing portion 2B (i.e., the second outermost shaft end 2Bc). In other words, the inverter module MJ is disposed between the outermost ends of the first housing portion 2A and the second housing portion 2B along the axial direction L. In the illustrated example, the first outermost shaft end 2Ac is the outermost end of the first axial side L1 of the first housing portion 2A. Furthermore, the second outermost shaft end 2Bc is the outermost end of the second axial side L2 of the second housing portion 2B.

[0098] However, although the junction box, which serves as a component connecting the power lines 1U, 1V, 1W of the rotating electric motor 1 to the inverter module MJ via the busbars 7U, 7V, 7W, is supported by the housing 2 of the rotating electric motor 1 (e.g., the peripheral wall portion 21), the junction box tends to become hot in the busbar path from the housing 2 to the inverter module MJ, where the heat from the busbars 7U, 7V, 7W is difficult to dissipate into the air. This type of busbar path, where the heat from the busbars 7U, 7V, 7W is difficult to dissipate into the air, is easily formed when the housing of the rotating electric motor 1 and the housing of the inverter module MJ are adjacent to or close to each other, or when they are a single, integrated housing.

[0099] Therefore, in the case of housing 2 as in this embodiment, the junction box (for example, refer to the following) Figure 3AThe bus module BM is prone to overheating. However, according to this embodiment, as described above, the power lines 1U, 1V, 1W and the bus 7U, 7V, 7W can be effectively cooled, thus appropriately preventing the junction box from overheating. That is, according to this embodiment, even when using a housing 2 integrally formed in such a way that the rotating motor 1 and the inverter module MJ are internally housed, overheating of the junction box can be appropriately prevented.

[0100] Next, refer to Figure 3A , Figure 5 as well as Figure 6 The structures related to oil are described.

[0101] like Figure 3A Briefly, the vehicle drive unit 100 includes: a mechanical hydraulic pump 71 driven by a driving force transmitted in the power transmission path P, and an electric hydraulic pump 72 driven by a dedicated driving force source independent of the power transmission path P. Both the mechanical hydraulic pump 71 and the electric hydraulic pump 72 are pumps that draw oil from an oil reservoir stored within the housing 2 and discharge the drawn oil.

[0102] In this embodiment, as an example, the mechanical hydraulic pump 71 is housed within the housing 2. Furthermore, in this embodiment, as an example, the mechanical hydraulic pump 71 is driven by the rotation of a rotating component included in the drive transmission mechanism 10. Additionally, the mechanical hydraulic pump 71 may be, for example, a gear pump.

[0103] Thus, in this embodiment, as an example, the mechanical hydraulic pump 71 is driven by the rotation of the differential housing 52 of the differential gear mechanism 5. The rotational speed of the differential housing 52 is lower than the rotational speed of the rotary motor 1 and the rotational speed of the reversing gear mechanism 4. Therefore, according to the structure in which the mechanical hydraulic pump 71 is driven by the rotation of the differential housing 52, compared to the structure in which the mechanical hydraulic pump 71 is driven by the rotary motor 1 or the reversing gear mechanism 4, the rotational speed of the mechanical hydraulic pump 71 can be suppressed to a lower level. As a result, the energy loss caused by the high-speed rotation of the mechanical hydraulic pump 71 can be minimized.

[0104] like Figure 3A Briefly, in this embodiment, as an example, the electric hydraulic pump 72 is an electric hydraulic pump driven by an electric motor (not shown). The electric motor can be, for example, an AC rotary motor driven by multiphase alternating current.

[0105] In this embodiment, as an example, the electric hydraulic pump 72 stops when the temperature of the cooling target part CP of the rotary motor 1 is below a predetermined value. Here, the "temperature of the cooling target part CP" can be the average value, maximum value, etc., if the cooling target part CP includes multiple parts. The cooling target part CP includes the outer peripheral surface 111a of the stator core 111, the inner peripheral surface 122d of the rotor shaft 122, and the coil end 112A. Furthermore, in a modified example, the electric hydraulic pump 72 may also stop based on other conditions related to the operating state of the rotary motor 1.

[0106] The vehicle drive unit 100 has independent lubrication oil passages 91 and 92.

[0107] The lubrication oil passage 91 supplies oil discharged from the mechanical hydraulic pump 71 to multiple bearings that support the rotor shaft 122 of the rotary motor 1 and various rotating components of the drive transmission mechanism 10, enabling them to rotate. The lubrication oil passage 91 includes the aforementioned input shaft oil passage 31a and secondary shaft oil passage 41a. The oil supplied to the input shaft oil passage 31a is used for lubricating the second rotor bearing B1b, the first input bearing B3a, etc. Furthermore, the oil supplied to the secondary shaft oil passage 41a is used for lubricating the first secondary bearing B4a, the second secondary bearing B4b, etc.

[0108] As described above, the oil passage 92 includes a cooling oil passage 921 and a second branch oil passage 922 (an example of the second oil passage portion). In addition, the cooling oil passage 921 has a third branch oil passage 923 downstream of the branch point of the second branch oil passage 922, and forms a first oil passage portion upstream of the branch point of the second branch oil passage 922.

[0109] Reference Figure 2 As described above, the cooling oil passage 921 is an oil passage that supplies oil discharged from the electric hydraulic pump 72 to the cooling target part CP inside the rotary motor 1.

[0110] exist Figure 3A In the example shown, the third branch oil passage 923 of the cooling oil passage 921 includes a rotor shaft oil passage 122a, which serves as the hollow interior of the rotor shaft 122. Furthermore, the third branch oil passage 923 of the cooling oil passage 921 has a first supply hole 82b, which acts as a drip hole for dripping oil to the coil end 112A. The first supply hole 82b may also be provided separately for the coil ends 112A on both sides of the axial direction. Figure 3A A more detailed description of the structure of the cooling oil passage 921 shown will be provided in the following description of the oil flow.

[0111] Reference Figure 2As described above, the second branch oil circuit 922 is connected to the cooling oil circuit 921 and supplies a portion of the oil discharged from the electric hydraulic pump 72 to the cooling oil circuit 921 to at least one of the power lines 1U, 1V, 1W and the bus lines 7U, 7V, 7W.

[0112] exist Figure 3A In the example shown, the second branch oil passage 922 is formed by a tubular component 86. The tubular component 86 can be formed of, for example, metal. The tubular component 86 is, for example, a closed circular shape, but the cross-sectional shape is arbitrary as long as it is closed. The tubular component 86 can be implemented by a single component or by connecting multiple components.

[0113] One end of the tubular component 86 is supported on the first sidewall portion 22. The end of the tubular component 86 on the first sidewall portion 22 side is connected to a cooling oil passage 921 (cooling oil passage 22b) formed within the first sidewall portion 22. The other end of the tubular component 86 is supported on the housing 2. Furthermore, although the method of supporting the other end of the tubular component 86 is not shown, it can be supported on the housing 2 in any manner. For example, the tubular component 86 can be welded to the housing 2, or it can be fixed to the housing 2 via a bracket or the like. The other end of the tubular component 86 is closed. That is, the end of the tubular component 86 on the first sidewall portion 22 side is open, while the other end is closed.

[0114] like Figure 3A As shown, the tubular component 86 is configured to pass near the busbars 7U, 7V, and 7W. Specifically, the tubular component 86 extends from one end of the first sidewall portion 22 toward the axial first side L1, and bends outward radially relative to the axis A1 midway. Moreover, the tubular component 86 extends outward radially relative to the axis A1 in such a manner that it passes near the busbars 7U, 7V, and 7W.

[0115] In addition, Figure 3A In the example shown, busbars 7U, 7V, and 7W are assembled within a busbar module BM, which is a junction box. That is, the busbar module BM is constructed using resin section 7R (see reference). Figure 6 The modules for sealing busbars 7U, 7V, and 7W are also described. Furthermore, the busbar module BM can be formed by resin embedding molding. The busbar module BM can, for example, be fixed to the peripheral wall portion 21.

[0116] like Figure 3A as well as Figure 6 As shown, the tubular component 86 has a spray hole 9221 for spraying oil toward the bus module BM. Here, "spraying oil toward the bus module BM" means something other than an indirect form of guiding oil toward the bus module BM by transferring oil to any object; it usually means releasing oil into the air so that the oil comes into direct contact with the bus module BM.

[0117] By using such a jet hole 9221, compared to a comparative structure such as arranging the bus module BM in the second branch oil passage 922 formed by the tubular component 86, the bus module BM can be arranged in a larger volume of air (i.e., in the space where the rotary motor 1 is housed), which can promote the release of heat into the air.

[0118] Furthermore, by using the injection hole 9221, it is easy to supply a sufficient amount of oil to the bus module BM. Specifically, when using the injection hole 9221, the oil injected from the injection hole 9221 comes into contact with the bus module BM without passing through other components, making it easy to manage (control) the amount of oil in contact with the bus module BM. That is, the amount of oil flowing within the tubular component 86 is actually equal to the amount of oil in contact with the bus module BM, so by managing (controlling) the amount of oil flowing within the tubular component 86, the management (control) of the amount of oil in contact with the bus module BM becomes easy.

[0119] Furthermore, in the case where the joints 9U, 9V, and 9W are immersed in oil, and the lubricating oil is applied to the joints 9U, 9V, and 9W by lifting, the oil adhering to the joints 9U, 9V, and 9W is prone to stagnation and corrosion. However, when the oil is sprayed through the spray hole 9221, the above problems can be reduced.

[0120] The injection orifice 9221 can be installed one by one corresponding to each of the buses 7U, 7V, and 7W, or multiple orifices can be installed corresponding to each of the buses 7U, 7V, and 7W. Figure 6 In the example shown, the injection port 9221 is configured to inject oil toward the junction 9V between the power line 1V and the busbar 7V. Specifically, in Figure 6 In the example shown, the power line 1V and the busbar 7V are joined by the fastening of bolt BT1, and the injection hole 9221 is located above the axis of bolt BT1. In this case, oil can be applied near the upper end of the area where the power line 1V and the busbar 7V overlap, which can efficiently cool both the power line 1V and the busbar 7V. That is, when the oil flows downward along the power line 1V and the busbar 7V to carry away heat from them, the oil flow range (the range along the power line 1V and the busbar 7V) is relatively long, so both the power line 1V and the busbar 7V can be cooled effectively at the same time.

[0121] In addition, oil discharged from the electric hydraulic pump 72 is supplied to the cooling oil circuit 921 and the associated second branch oil circuit 922, so the amount of oil supplied to the second branch oil circuit 922 can be adjusted by controlling the operating state of the electric hydraulic pump 72.

[0122] Furthermore, by utilizing the tubular component 86, the layout of the second branch oil passage 922 becomes more flexible compared to the case of using an internal oil passage within the housing. As a result, even with various layouts of the power lines and busbars, it is easy to form a second branch oil passage 922 that can effectively cool the power lines and busbars.

[0123] Next, refer to Figure 3A as well as Figure 6 The flow of oil in oil passage 92 is explained. Figure 3A as well as Figure 6 In the diagram, arrows R0 to R11 are used to schematically represent the flow of oil.

[0124] like Figure 3A As shown, the electric hydraulic pump 72 draws oil introduced via the filter 74 (arrow R0) through the inlet oil passage 23a formed in the second sidewall portion 23. The oil discharged from the electric hydraulic pump 72 is cooled by the oil cooler 73. The oil cooler 73 is configured, for example, as a piping system for oil flow, and cools the oil by heat exchange between a refrigerant (e.g., cooling water, air, etc.) flowing outside the piping and the oil inside the piping. Thus, in this embodiment, as an example, an oil cooler 73 for cooling oil is provided in the cooling oil passage 921. On the other hand, no oil cooler for cooling oil is provided in the lubrication oil passage 91.

[0125] The oil cooled by the oil cooler 73 is introduced into the inlet oil passage 23b (arrow R1) formed in the second side wall portion 23, and supplied to the cooling oil passage 22b formed in the first side wall portion 22 of the housing 2 via the oil passage 24a formed in the partition wall portion 24 (arrows R2, R3). The oil supplied to the cooling oil passage 22b flows inward toward the radial direction R with reference to the shaft A1 (arrow R4), and is diverted to the second branch oil passage 922 midway (arrow R6). The oil that does not divert to the second branch oil passage 922 but flows in the cooling oil passage 22b (third branch oil passage 923) (arrow R5) is diverted to the first connecting oil passage 22c at the position on the shaft A1 (arrow R7). The oil that does not divert to the first connecting oil passage 22c but flows in the cooling oil passage 22b (arrow R8) flows into the second connecting oil passage 22d connected to the outer supply oil passage 82a.

[0126] Oil flowing into the second branch oil passage 922 is sprayed towards the bus module BM through the injection port 9221, and applied to the buses 7U, 7V, 7W and the power lines 1U, 1V, 1W of the rotary motor 1. As a result, the buses 7U, 7V, 7W and the power lines 1U, 1V, 1W within the bus module BM are cooled. Furthermore, as... Figure 6 As shown, the busbars 7U, 7V, and 7W of busbar module BM are the same as the busbars of inverter module MJ (refer to...). Figure 6The busbar 7IV) is connected. Therefore, the busbar module BM can also be cooled via busbars 7U, 7V, and 7W. Furthermore, in Figure 6 In the process, the bus 7IV of inverter module MJ is connected to the bus 7V of bus module BM by tightening bolt BT2.

[0127] Oil flowing into the first connecting oil passage 22c is supplied to the rotor shaft oil passage 122a (the inner circumferential surface 122d of the rotor shaft 122) via this passage. Alternatively, oil can be supplied to the rotor shaft oil passage 122a via a tubular component (not shown) connected to the first connecting oil passage 22c. The oil supplied to the inner circumferential surface 122d of the rotor shaft 122 undergoes heat exchange with the permanent magnet 123 via the rotor shaft 122 and rotor core 121, thereby cooling the permanent magnet 123. In this case, the cooling target portion CP includes the inner circumferential surface 122d of the rotor shaft 122 and the permanent magnet 123.

[0128] A portion of the oil supplied to the rotor shaft oil passage 122a flows into each of the first supply oil passage 122b and the second supply oil passage 122c, which are formed to extend radially through the rotor shaft 122. Here, the first supply oil passage 122b, when viewed radially along the rotor shaft 122, is formed at a position overlapping the coil end 112A on the axial first side L1. Similarly, the second supply oil passage 122c, when viewed radially along the rotor shaft 122, is formed at a position overlapping the coil end 112A on the axial second side L2. Therefore, with the rotation of the rotor shaft 122, oil is sprayed from each of the first supply oil passage 122b and the second supply oil passage 122c toward the corresponding coil end 112A. Furthermore, the oil adhering to the coil end 112A cools it. In this case, the cooling target portion CP includes the coil end 112A.

[0129] On the other hand, the oil flowing into the second connecting oil passage 22d passes through the second connecting oil passage 22d and is supplied to the outer supply oil passage 82a. The outer supply oil passage 82a is an oil passage formed in the outer supply member 82. The outer supply member 82 is disposed on the upper side in the vertical direction relative to the rotary motor 1. Specifically, the outer supply member 82 is disposed on the upper side in the vertical direction relative to the coil end 112A and the stator core 111. The outer supply member 82 is formed to extend along the axial direction L. The outer supply member 82 is formed as a cylindrical shape with an open end face on the first axial side L1. Moreover, the internal space of the outer supply member 82 functions as the outer supply oil passage 82a. The end of the outer supply member 82 on the first axial side L1 is supported on the first sidewall portion 22 in a manner that connects the outer supply oil passage 82a and the second connecting oil passage 22d. On the other hand, the end of the outer supply member 82 on the second axial side L2 is supported on the partition wall portion 24.

[0130] The oil supplied to the outer supply oil passage 82a flows toward the second axial side L2 in the outer supply oil passage 82a. Moreover, the oil in the outer supply oil passage 82a falls through the first supply hole 82b and the second supply hole 82c formed in such a way that they pass through the outer supply member 82 in the radial direction R.

[0131] When viewed vertically, the first supply holes 82b are arranged at multiple positions (two positions in the illustrated example) along the axial L direction, overlapping with the coil end 112A on the axial first side L1 and the coil end 112A on the axial second side L2, and are spaced apart circumferentially on the outer supply member 82. Therefore, a portion of the oil in the outer supply oil passage 82a drips through the first supply holes 82b onto the coil end 112A. Furthermore, the oil adhering to the coil end 112A is used to cool the coil end 112A.

[0132] Furthermore, the second supply hole 82c, when viewed vertically, is positioned overlapping the stator core 111. In the illustrated example, the second supply hole 82c is positioned at multiple locations along the axial direction L (two locations in the illustrated example), and is spaced apart circumferentially on the outer supply member 82. Therefore, a portion of the oil in the outer supply oil passage 82a drips onto the outer peripheral surface 111a of the stator core 111 through the second supply hole 82c. The oil dripping onto the outer peripheral surface 111a of the stator core 111 undergoes heat exchange with the coil 112 wound on the stator core 111 via the stator core 111, thereby cooling the coil 112. In this case, the cooling target portion CP includes the outer peripheral surface 111a of the stator core 111.

[0133] Thus, according to Figure 3A In the example shown, based on the oil discharged by the electric hydraulic pump 72, the cooling target part CP inside the rotary motor 1 can be effectively cooled via the cooling oil passage 921 and the second branch oil passage 922, and the busbars 7U, 7V, 7W and the power lines 1U, 1V, 1W can also be effectively cooled. As a result, efficient oil cooling of the entire vehicle drive unit 100 can be achieved using the oil from the electric hydraulic pump 72.

[0134] In addition, according to Figure 3AIn the example shown, the lubrication oil circuit 91 and the cooling oil circuit 921 are provided independently. Therefore, in the vehicle drive unit 100, the hydraulic circuit for lubrication and the hydraulic circuit for cooling are independent of each other. As a result, when it is not necessary to supply oil to either of them, it is possible to avoid supplying oil to both of them. For example, when the vehicle equipped with the vehicle drive unit 100 is traveling at high speed, and the rotary motor 1 is under low load, the supply of oil from the electric hydraulic pump 72 to the cooling part CP can be stopped. As a result, the energy loss caused by the unnecessary drive of the electric hydraulic pump 72 can be minimized.

[0135] Furthermore, the lubricating oil used for cooling and lubricating the rotating motor 1 tends to reach high temperatures when the output of the rotating motor 1 is relatively high. If the lubricating oil reaches high temperatures, its cooling capacity will decrease. Therefore, by separately providing a lubrication oil passage 91 and a cooling oil passage 921, it is possible to prevent adverse situations (insufficient cooling capacity) that may occur when the lubricating oil in the lubrication oil passage 91 is used for cooling the power lines 1U, 1V, 1W and the busbars 7U, 7V, 7W.

[0136] In addition, Figure 3A In the example shown, the amount of oil discharged by the electric hydraulic pump 72 and allocated to the second branch oil passage 922 can also be adjusted based on the respective opening areas of the first supply oil passage 122b, the second supply oil passage 122c, the first supply orifice 82b, the second supply orifice 82c, and the injection orifice 9221. For example, the amount of oil allocated to the second branch oil passage 922 can also be adjusted based on the relationship between the sum α2 of the opening areas of the first supply oil passage 122b, the second supply oil passage 122c, the first supply orifice 82b, and the second supply orifice 82c and the total area α1 of the injection orifice 9221 (e.g., the ratio α1 / (α1+α2)). In this case, as described above, the ratio α1 / (α1+α2) is preferably 0.3 or less, and more preferably around 0.1. In this case, by distributing oil from the electric hydraulic pump 72 in an appropriate ratio, the cooling target part CP inside the rotary motor 1, and the power lines 1U, 1V, 1W and busbars 7U, 7V, 7W of the rotary motor 1 can be cooled efficiently.

[0137] In addition, Figure 3A In the example shown, although the second branch oil passage 922 is formed by a single tubular component 86, two or more tubular components 86 may be connected to the cooling oil passage 921 in parallel. In addition, tubular components (tubular components other than tubular component 86) used to cool other parts to be cooled may also be connected to the cooling oil passage 921.

[0138] While the embodiments have been described in detail above, they are not limited to specific embodiments. Various modifications and alterations can be made within the scope of the technical solutions described. Furthermore, all or multiple structural components of the above embodiments can be combined.

[0139] For example, in the above embodiment, although the oil supply unit 8 includes an electric hydraulic pump 72, a mechanical hydraulic pump can be used instead of an electric hydraulic pump 72.

[0140] Furthermore, although the oil supply unit 8 includes an oil cooler 73 in the above embodiment, the oil cooler 73 may be omitted. Additionally, the oil cooler 73 can be located in any position. For example, the oil cooler 73 may be located inside the inverter housing 2a. In this case, the oil cooler 73 can also be implemented using the cooling water passage passing through the inverter module MJ. Specifically, the oil passage 92 may extend into the inverter housing 2a, adjacent to the cooling water passage passing through the inverter module MJ, thereby lowering the temperature of the oil flowing in the oil passage 92. Furthermore, in this case, the cooling water circulating in the cooling water passage can be cooled by a radiator. Alternatively, when the rotating motor 1 is water-cooled, the oil cooler 73 can also be implemented using the cooling water used for water cooling described above.

[0141] Explanation of reference numerals in the attached figures

[0142] 100…Automotive drive unit, 1…Rotary motor, 2…Housing, 21…Peripheral wall (partition), 1U, 1V, 1W…Power lines, 7U, 7V, 7W…Buslines, Joint…9U, 9V, 9W, 11…Stator, 112…Coil, 121…Rotor core, 122…Rotor shaft, 122a…Rotor shaft oil passage (hollow interior), 72…Electric hydraulic pump (hydraulic pump), 721…Pump motor, 73…Oil cooling Device, 92… oil circuit, 921… cooling oil circuit (first oil circuit section), 922… second branch oil circuit (second oil circuit section), 923… third branch oil circuit (third oil circuit section), 82b… first supply hole (drip hole), 9221… spray hole, IV… inverter (power converter), HB… high voltage battery (power supply), BT1… bolt, SP1… space (first storage chamber), SP2… closed space (second storage chamber).

Claims

1. A vehicle drive unit, comprising: case; A rotary motor, which is housed within the aforementioned housing, and has a power line electrically connected to a power source via a power converter; The busbar extends within the aforementioned housing and engages with the aforementioned power line; Hydraulic pumps; and The oil passage has injection holes for injecting oil discharged from the hydraulic pump toward at least one of the power line and the busbar. The rotor core of the aforementioned rotating electric motor is arranged around a hollow rotor shaft. The stator of the aforementioned rotary electric machine is wound with coils having coil ends that are electrically connected to the aforementioned power lines. The above-mentioned oil circuit includes: First Oil Route Department; The second and third oil circuit sections are respectively connected to the first oil circuit section. The second oil circuit supplies oil to at least one of the power line and the busbar. The aforementioned third oil passage includes the hollow interior of the aforementioned rotor shaft, and has a drip hole at the end of the aforementioned coil for dripping the aforementioned oil onto the aforementioned coil. The drip hole is disposed on the upper side in the vertical direction relative to the end of the aforementioned coil, and is disposed at a position that overlaps with the end of the aforementioned coil when viewed in the vertical direction.

2. The vehicle drive device according to claim 1, wherein, The aforementioned hydraulic pump has a pump motor and supplies oil cooled by an oil cooler to the aforementioned oil circuit.

3. The vehicle drive unit according to claim 1 or 2, wherein, The aforementioned power line and the aforementioned busbar are connected by tightening bolts. The second oil passage section has an injection hole for injecting oil toward the joint between the power line and the busbar. The aforementioned injection hole is located above the shaft of the aforementioned bolt.

4. The vehicle drive unit according to claim 1 or 2, wherein, The aforementioned housing is integrally formed such that it has a first storage chamber for housing the aforementioned rotary motor and a second storage chamber for housing the aforementioned power converter, and is provided with a partition wall dividing the aforementioned first storage chamber and the aforementioned second storage chamber. The aforementioned busbar is configured to pass through the aforementioned partition wall.

5. The vehicle drive unit according to claim 3, wherein, The aforementioned housing is integrally formed such that it has a first storage chamber for housing the aforementioned rotary motor and a second storage chamber for housing the aforementioned power converter, and is provided with a partition wall dividing the aforementioned first storage chamber and the aforementioned second storage chamber. The aforementioned busbar is configured to pass through the aforementioned partition wall.

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