Vehicle drive device

Abstract

To provide a technology capable of properly cooling and lubricating a driving device for a vehicle by using oil, and utilizing exhaust heat via the oil with higher utilization efficiency.SOLUTION: In the vehicle drive device 1 including the rotating electric machine 2, the power transmission mechanism 3, the case 9, and the oil supply device 5, the oil supply device 5 supplies oil to both the rotating electric machine 2 and the power transmission mechanism 3 when the rotational speed of the output member is higher than the reference speed, and supplies oil to the rotating electric machine 2 without supplying oil to the power transmission mechanism 3 when the rotational speed of the output member is equal to or lower than the reference speed.SELECTED DRAWING: Figure 4

Description

[Technical Field]

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

[0002] Japanese Patent Application Laid-Open Publication No. 2024-40788 discloses a vehicle drive device (1) including a rotating electric machine (2) that drives wheels, a gear mechanism (3) that transmits power from the rotating electric machine (2) to the wheels, and a mechanism that supplies oil for lubrication (including cooling) to the rotating electric machine (2) and the gear mechanism (3) (reference numerals in parentheses in the Background Art are those of the referenced document). A housing space (80) of a case (6) that houses the rotating electric machine (2) and the gear mechanism (3) is partitioned into a rotating electric machine housing chamber (81), a gear housing chamber (82), and an oil storage chamber (85) that stores oil. A first oil reservoir (P1) that stores oil is provided in a lower region of the gear housing chamber (82), and a second oil reservoir (P2) that stores oil is provided in a lower region of the rotating electric machine housing chamber (81). The bottom (81a) of the rotating electric machine accommodation chamber (81) is located above the bottom (82a) of the gear accommodation chamber (82). The oil that lubricates (cools) the rotating electric machine (2) moves from the second oil reservoir (P2) to the first oil reservoir (P1) through the partition wall opening (68) provided in the partition wall (60b) that separates the rotating electric machine accommodation chamber (81) from the gear accommodation chamber (82).

[0003] The gear mechanism (3) in the gear accommodating chamber (82) is supplied with oil by the gears of the gear mechanism (3) scooping up oil from the first oil sump (P1). The oil supplied to the gears, bearings, etc. drips down and is stored again in the first oil sump (P1). The first oil sump (P1) and the oil storage chamber (85) are connected by a communication passage (92c), and a portion of the oil in the first oil sump (P1) is supplied to the oil storage chamber (85). The oil in the oil storage chamber (85) is sucked in and discharged by the pump (96), passes through the cooler (97), and is supplied to the rotating electric machine (2) via an oil passage formed in the wall of the case (6), etc. The oil supplied to the rotating electric machine (2) drips into the second oil sump (P2) and moves to the first oil sump (P1) through the partition wall opening (68). The cooler (97) exchanges heat between the oil and the first refrigerant (R). The first refrigerant (R) further exchanges heat with outside air or another refrigerant (second refrigerant (R2)) in the radiator (126) or the chiller (125). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2024-40788 Summary of the Invention [Problem to be solved by the invention]

[0005] Heat generated in a vehicle drive system is not only discarded via a radiator, but may also be utilized in a chiller or the like. When considering the utilization of waste heat, it is preferable that the heat generated in the vehicle drive system be transmitted without waste to the heat utilization destination. In the above-described vehicle drive system, the oil supplied to the rotating electric machine and the oil supplied to the gear mechanism always flow together, so when the oil temperature is low, the oil temperature does not easily increase, making it difficult to improve the utilization efficiency of the waste heat.

[0006] Therefore, it is desirable to provide a technology that can appropriately cool and lubricate a vehicle drive device using oil and that can utilize waste heat via oil with higher utilization efficiency. [Means for solving the problem]

[0007] In view of the above, a vehicle drive device is a vehicle drive device comprising a rotating electric machine, an output member drivingly connected to a wheel, a power transmission mechanism that transmits power between the rotating electric machine and the output member, a case that houses the rotating electric machine and the power transmission mechanism, and an oil supply device that can supply oil to multiple locations within the case, wherein the oil supply device supplies oil to both the rotating electric machine and the power transmission mechanism when the rotational speed of the output member is higher than a predetermined reference speed, and does not supply oil to the power transmission mechanism when the rotational speed of the output member is equal to or lower than the reference speed, and supplies oil to the rotating electric machine.

[0008] According to this configuration, when the rotational speed of the output member is higher than the reference speed, both the rotating electrical machine and the power transmission mechanism, which require cooling and lubrication, can be appropriately cooled and lubricated. On the other hand, when the rotational speed of the output member is lower than the reference speed, oil is not supplied to the power transmission mechanism, which requires less cooling and lubrication, thereby appropriately cooling and lubricating the rotating electrical machine and efficiently raising the oil temperature. In other words, according to this configuration, the vehicle drive system can be appropriately cooled and lubricated using oil, and waste heat can be utilized more efficiently via the oil.

[0009] Further features and advantages of the vehicle drive device will become apparent from the following description of exemplary, non-limiting embodiments which are given with reference to the drawings. [Brief explanation of the drawings]

[0010] [Figure 1] A system configuration diagram showing an example of a vehicle drive system using a skeleton. [Figure 2] FIG. 1 is a diagram showing a first example of the configuration of an oil distribution path including a vehicle drive device; [Figure 3] FIG. 10 is a diagram showing a first oil flow pattern in a second example of the oil flow path configuration. [Figure 4] FIG. 10 is a diagram showing a second oil flow pattern in a second example of the oil flow path configuration. [Figure 5] FIG. 1 is a diagram showing a conventional example of the configuration of an oil distribution path including a vehicle drive device. DETAILED DESCRIPTION OF THE INVENTION

[0011] An embodiment of a vehicle drive device will be described below with reference to the drawings. As shown in FIG. 1, the vehicle drive device 1 of this embodiment includes a rotating electric machine 2, an output member 33 drivingly connected to wheels 4, and a power transmission mechanism 3 that transmits power between the rotating electric machine 2 and the output member 33. As shown in FIG. 2 and other figures, the vehicle drive device 1 includes a case 9 that houses the rotating electric machine 2 and the power transmission mechanism 3. Also, as shown in FIGS. 1 and 2 and other figures, the vehicle drive device 1 includes an oil supply device 5 that can supply oil to the case 9 to cool (and lubricate) the rotating electric machine 2 and the power transmission mechanism 3. The oil supply device 5 cools and lubricates the rotating electric machine 2 and the power transmission mechanism 3 by supplying oil to multiple locations within the case 9. In the following description, unless otherwise specified, the terms "cooling" and "lubrication" include both the meanings of "cooling" and "lubrication."

[0012] 1 illustrates an example of the configuration of the rotating electric machine 2 and the power transmission mechanism 3 to which oil is supplied, but the configurations of the rotating electric machine 2 and the power transmission mechanism 3 are not limited to this example. In the example illustrated in FIG. 1, the rotating electric machine 2 is a traction motor that receives power from an on-board DC power supply (not shown) and serves as a driving power source for the wheels 4, and also functions as a generator that generates power using power transmitted from the wheels 4 and the like to charge the DC power supply. In this embodiment, the rotating electric machine 2 is an inner-rotor rotating electric machine that includes a rotor 21 and a stator 22 disposed radially outward of the rotor 21. Destinations to which oil is supplied include bearings (not shown) that rotatably support the rotor 21 relative to the case 9, a stator coil 23 included in the stator 22, and cores (rotor core and stator core) of the rotor 21 and the stator 22.

[0013] In this embodiment, a vehicle drive system 1 having a three-shaft configuration is illustrated, in which rotating members are arranged around a first shaft A1, a second shaft A2, and a third shaft A3, which are parallel to each other and have respective rotation axes. The rotating electric machine 2 is arranged on the first shaft A1. A reducer 31 that reduces the rotation speed of the rotor 21 of the rotating electric machine 2 is arranged on the second shaft A2. In the illustrated example, the reducer 31 is a counter gear mechanism. A differential device 32 that distributes power transmitted from the rotor 21 via the reducer 31 to a pair of wheels 4 is arranged on the third shaft A3. In the illustrated example, the differential device 32 is a bevel gear-type differential mechanism, and the side gears of the bevel gear mechanism, or the drive shaft 44 that connects the side gears to the wheels 4, or the connection portion between the connecting shaft and the side gears, correspond to the output member 33. The reducer 31 and the differential device 32 correspond to the power transmission mechanism 3.

[0014] As described above, the configuration of the power transmission mechanism 3 is not limited to the illustrated embodiment. For example, the vehicle drive system 1 may have a two-shaft configuration (a folded two-shaft configuration) in which the differential device 32 is disposed on the first shaft A1. The vehicle drive system 1 may also have a two-shaft configuration in which the reducer 31 is configured by a planetary gear mechanism and is disposed coaxially with the rotor 21. The vehicle drive system 1 may also have a single-shaft configuration in which the rotor 21, the reducer 31 of a planetary gear mechanism, and the differential device 32 by a bevel gear mechanism or a planetary gear mechanism are disposed coaxially. The vehicle drive system 1 may also have a four-shaft or more configuration in which the reducer 31 is disposed on two or more shafts. The vehicle drive system 1 may also not have a differential device 32 and transmit power from the rotating electric machine 2 to one wheel 4. In this case, the output member 33 corresponds to an output shaft connected to the wheel 4, a final gear of the reducer 31, or a connection between the reducer 31 and the output shaft. Furthermore, the vehicle drive device 1 may include an internal combustion engine (not shown) that provides power to the rotating electric machine 2 when the rotating electric machine 2 functions as a generator. Regardless of the form of the power transmission mechanism 3, the power transmission mechanism 3 includes various transmission shafts and various gears. The power transmission mechanism 3 may also include engaging elements such as a clutch and a brake.

[0015] The rotating electric machine 2 and the power transmission mechanism 3 may be housed in the same housing chamber within the case 9. However, in this embodiment, as shown in FIG. 2 and other figures, the case 9 includes a first chamber 91 and a second chamber 92 that are separated from each other by a partition member such as a partition wall. The rotating electric machine 2 is housed in the first chamber 91, and the power transmission mechanism 3 is housed in the second chamber 92. As is clear from the skeleton diagram in FIG. 1 , the rotor 21 and the reducer 31 are drivably connected via gears or the like, and therefore, a portion of the power transmission member between the rotor 21 and the reducer 31 may be located within the first chamber 91. In other words, the core components of the power transmission mechanism 3 are housed in the second chamber 92, and a portion of the power transmission mechanism 3 is housed in the first chamber 91. In other words, at least a portion of the power transmission mechanism 3 is housed in the second chamber 92.

[0016] 2 to 5 show oil distribution paths including the vehicle drive system 1. FIGS. 2 to 4 show oil distribution paths in the vehicle drive system 1 according to this embodiment, and FIG. 5 shows a conventional oil distribution path in a vehicle drive system 1 serving as a comparative example. Oil is stored in an oil reservoir (oil sump) below the case 9. As described above, the first chamber 91 and the second chamber 92 are partitioned, with a first oil reservoir 93 below the first chamber 91 and a second oil reservoir 94 below the second chamber 92. An oil outlet 97 is provided in the oil reservoir, and oil stored in the oil reservoir is discharged from the oil outlet 97 to the outside of the case 9. A first oil inlet 98 is provided in the first chamber 91, and oil is supplied to the rotating electric machine 2 housed in the first chamber 91 via the first oil inlet 98. A second oil inlet 99 is provided in the second chamber 92, and oil is supplied to the power transmission mechanism 3 housed in the second chamber 92 via the second oil inlet 99. Since both have the same function as an inlet for introducing oil into the case 9, in the following description, the first oil inlet 98 and the second oil inlet 99 may be collectively referred to as the "oil inlet."

[0017] An oil pump 50 and an oil cooler 7 (heat exchanger, first heat exchanger) are arranged outside the case 9. In one embodiment, the oil pump 50 and the oil cooler 7 are attached to the side surface of the case 9, and can constitute a vehicle drive device 1 together with the rotating electric machine 2, the power transmission mechanism 3, and the case 9.

[0018] As shown in FIGS. 2 to 5 , in this embodiment and the comparative example, the oil cooler 7 and the oil pump 50 are arranged in series between the oil discharge port 97 and the oil inlets (first oil inlet 98, second oil inlet 99) in the oil flow path. More specifically, in the first configuration example shown in FIG. 2 and the comparative example (conventional example) shown in FIG. 5 , the oil flow path is, from upstream, the oil discharge port 97, the oil cooler 7, the oil pump 50, and the oil inlet. Furthermore, in the second configuration example shown in FIGS. 3 and 4 , when the first flow configuration shown in FIG. 3 is adopted, the oil flow path is similarly, from upstream, the oil discharge port 97, the oil cooler 7, the oil pump 50, and the oil inlet. On the other hand, when the second configuration example adopts the second flow configuration shown in FIG. 4 , the order of the oil cooler 7 and the oil pump 50 is reversed, and the oil flow path is, from upstream, the oil discharge port 97, the oil pump 50, the oil cooler 7, and the oil inlet.

[0019] Although not shown in the drawings, the order of the oil cooler 7 and the oil pump 50 may be reversed in each configuration. That is, in the first flow configuration in the first configuration example, the second configuration example, and the comparative example, the oil flow path may be in the order of, from upstream, the oil discharge port 97, the oil pump 50, the oil cooler 7, and the oil inlet. In this case, in the second flow configuration in the second configuration example, the oil flow path is in the order of, from upstream, the oil discharge port 97, the oil cooler 7, the oil pump 50, and the oil inlet.

[0020] The oil cooler 7 is a heat exchanger (first heat exchanger) that exchanges heat between the oil circulated by the oil supply device 5 and a heat medium 75. The heat medium 75 is further heat-exchanged in a second heat exchanger 70. Here, the heat medium 75 is, for example, a coolant (LLC: Long Life Coolant). When the heat medium 75 is coolant, the heat medium 75 exchanges heat with outside air, for example, in a radiator. The heat medium 75 may also exchange heat with a DC power source in a battery cooler (not shown) that cools (and warms) the DC power source. The heat medium 75 may also exchange heat with a refrigerant of an on-board air conditioner in a chiller or the like. The air conditioner refrigerant can further exchange heat with air in a cabin condenser of the air conditioner to heat the vehicle interior. Naturally, the heat medium 75 may exchange heat with two or more of the radiator, battery cooler, and chiller. The radiator, battery cooler, and chiller correspond to the second heat exchanger 70. Note that the heat medium 75 is not limited to coolant, but may be the refrigerant of an air conditioner. In this case, heat is exchanged between the refrigerant and the DC power supply in the battery cooler.

[0021] As shown in FIG. 5 , in the comparative example (conventional example), oil discharged from the first pump port 51 of the oil pump 50 is introduced into the case 9 through a first oil inlet 98 and a second oil inlet 99. The oil passage connecting the first pump port 51 and the first oil inlet 98 is a first oil passage 11, and the oil passage connecting the first pump port 51 and the second oil inlet 99 is a second oil passage 12. The oil introduced from the first oil inlet 98 into the first chamber 91 cools and lubricates the stator coil 23, bearings, etc., and drips into the first oil reservoir 93. The oil introduced from the second oil inlet 99 into the second chamber 92 lubricates the gears (meshing portions), bearings, etc. of the power transmission mechanism 3, and drips into the second oil reservoir 94. A communication passage 95 is formed in the partition wall separating the first chamber 91 and the second chamber 92, and the first oil reservoir 93 and the second oil reservoir 94 are in communication with each other. An oil discharge port 97 (suction port) provided in the first oil reservoir 93 is connected to the cooler first port 71 of the oil cooler 7, and the oil is introduced into the oil cooler 7 from the cooler first port 71. The oil exchanges heat with the heat medium 75 in the oil cooler 7 and is discharged from the cooler second port 72. The cooler second port 72 is connected to the pump second port 52 of the oil pump 50 via the connecting oil passage 14, and the oil pump 50 draws oil from the pump second port 52.

[0022] As described above, the heat generated in the vehicle drive device 1 is not only discarded via the radiator, but may also be utilized in a battery cooler (which functions as a heater in this case), a chiller, or the like. When considering such utilization of exhaust heat, it is preferable that the heat generated in the vehicle drive device 1 is transmitted without waste to the second heat exchanger 70, which is the heat utilization destination. In the vehicle drive device 1 of the comparative example shown in FIG. 5, the oil supplied to the rotating electric machine 2 and the oil supplied to the power transmission mechanism 3 always flow together, so that when the oil temperature is low, the oil temperature does not easily increase, and it is difficult to improve the utilization efficiency of the exhaust heat.

[0023] For example, when a vehicle is stopped in a low-temperature environment, the temperatures of the vehicle drive system 1 and the DC power supply also drop to approximately the same as the ambient temperature. When charging the DC power supply using an external power supply in this environment, charging efficiency decreases, so it is preferable to warm up the DC power supply using a battery cooler. Even when the vehicle is stopped, for example, the stator coil 23 can be heated by passing a current through the stator coil 23 without generating torque in the rotating electric machine 2. The oil then absorbs the heat from the stator coil 23, thereby increasing the temperature of the oil in the first oil reservoir 93. However, when the vehicle is stopped, the temperature of the power transmission mechanism 3 does not increase, so the temperature of the oil in the second oil reservoir 94 is unlikely to increase.

[0024] For this reason, in this embodiment, the oil supply device 5 is configured to be able to switch between an oil supply state between a first supply state in which oil is supplied to both the rotating electric machine 2 and the power transmission mechanism 3, and a second supply state in which oil is supplied to the rotating electric machine 2 without supplying oil to the power transmission mechanism 3. When the rotating electric machine 2 is not rotating or the wheels 4 are not rotating, i.e., when the output member 33 is not rotating, the rotating members constituting the power transmission mechanism 3 are not rotating and no lubrication is necessary. Furthermore, even if the rotating members constituting the power transmission mechanism 3 are rotating, if the rotational speed is low, lubrication by oil remaining in the sliding parts between the bearings and the rotating members and in the meshing parts of the gears, or oil running down the gears immersed in the second oil reservoir 94, may be sufficient, and additional oil may not be immediately required. Therefore, in this embodiment, when the rotational speed of the output member 33 is higher than a predetermined reference speed, the oil supply device 5 supplies oil to both the rotating electric machine 2 and the power transmission mechanism 3 (first supply state), and when the rotational speed of the output member 33 is equal to or lower than the reference speed, the oil supply device 5 does not supply oil to the power transmission mechanism 3 but supplies oil to the rotating electric machine 2 (second supply state).

[0025] Note that "oil is not supplied to the power transmission mechanism 3" does not refer to a completely shut-off state in which not a single drop of oil is supplied, but rather refers to oil not being actively supplied. The second supply state may include, for example, the oil remaining in the oil passage flowing to the power transmission mechanism 3 after transition from the first supply state to the second supply state, the oil leaking from the switching valve 8 being supplied to the power transmission mechanism 3 when the oil passage is controlled by the switching valve 8 or the like, and the oil to the rotating electric machine 2 bypassing the oil passage and being also supplied to the power transmission mechanism 3. Furthermore, "oil is not actively supplied" also includes a case in which oil is allowed to flow to the power transmission mechanism 3, but the amount of oil is small compared to the amount of oil supplied to the rotating electric machine 2.

[0026] Here, the "reference speed" is, for example, "zero," which corresponds to a state in which the rotor 21 and the power transmission mechanism 3 are not rotating, such as when the vehicle is stopped. If an engaging element such as a clutch is provided between the rotor 21 and the reducer 31, the rotor 21 may be rotating as long as the output member 33 is not rotating when the clutch is released. As described above, the rotating members of the power transmission mechanism 3 may be rotating at a low speed, and the "reference speed" may be approximately 5 to 10 kilometers per hour when converted into the rotational speed of the wheels 4.

[0027] In this way, by switching between the first supply state and the second supply state, when the rotational speed of the output member 33 is higher than the reference speed, it is possible to appropriately cool and lubricate both the rotating electric machine 2 and the power transmission mechanism 3, which require cooling and lubrication. On the other hand, when the rotational speed of the output member 33 is equal to or lower than the reference speed, oil is not supplied to the power transmission mechanism 3, which does not require cooling or lubrication as much, thereby appropriately cooling and lubricating the rotating electric machine 2 and efficiently increasing the oil temperature. Note that, if the vehicle drive device 1 has oil supply destinations other than the rotating electric machine 2 and the power transmission mechanism 3, the second supply state does not prevent oil from being supplied to those other supply destinations.

[0028] To switch between the first supply state and the second supply state, the oil supply device 5 cooperates with the control device 6. The control device 6 controls the oil supply device 5 based on the detection result of a rotational speed sensor 66 that detects the rotational speed of the output member 33. The rotational speed sensor 66 may be a sensor that directly detects the rotational speed of the output member 33, or a sensor that detects the rotational speed of a rotating element that has linearity with the rotational speed of the output member 33, such as the wheels 4 or another rotating member in the power transmission mechanism 3. Furthermore, the control device 6 may switch between the first supply state and the second supply state using, in addition to the rotational speed sensor 66, other determination conditions such as the outside air temperature, the temperature of the device (DC power supply) to be warmed up, and the requested heating temperature. That is, the first supply state and the second supply state may be switched based on the rotational speed of the output member 33, provided that there is a request to heat the oil (a request for utilizing exhaust heat: warming up, heating, etc.).

[0029] 1 to 4, the oil supply device 5 and the control device 6 are shown as independent functional units, but this is for ease of understanding. The oil supply device 5 may be configured to include the control device 6.

[0030] In one aspect, switching between the first supply state and the second supply state is achieved using an electromagnetic control valve 88 (switching valve 8), as in a first configuration example shown in FIG. 2 . The control device 6 controls at least the oil pump 50 and the electromagnetic control valve 88. In the first supply state, the control device 6 controls the electromagnetic control valve 88 to an open state (a flow-through state) and drives the oil pump 50. The oil pump 50 is, for example, an electric oil pump, and is controlled to a first rotation state in which a drive source such as a pump motor rotates in a first rotation direction C1, causing oil to be discharged from a first pump port 51 (discharge port) of the oil pump 50. Note that the drive source of the oil pump 50 is not limited to a motor. Because the electromagnetic control valve 88 is in the open state, the discharged oil is supplied to both a first oil passage 11 that supplies oil from the oil pump 50 to the rotating electric machine 2 and a second oil passage 12 that supplies oil from the oil pump 50 to the power transmission mechanism 3.

[0031] In the second supply state, the control device 6 controls the electromagnetic control valve 88 to a closed state (non-flow state) and drives the oil pump 50. As in the first supply state, a drive source such as a pump motor is controlled to a first rotation state in which it rotates in a first rotation direction C1, and oil is discharged from the first pump port 51 (discharge port) of the oil pump 50. However, because the electromagnetic control valve 88 is in a closed state, the discharged oil is supplied to the first oil passage 11 that supplies oil from the oil pump 50 to the rotating electrical machine 2, but is not supplied to the second oil passage 12 that supplies oil from the oil pump 50 to the power transmission mechanism 3.

[0032] That is, in the first configuration example, the oil supply device 5 includes an oil pump 50 that sucks in and discharges oil in a case 9, a control device 6 that controls the oil pump 50, a first oil passage 11 that supplies the oil discharged by the oil pump 50 to the rotary electric machine 2, a second oil passage 12 that supplies the oil discharged by the oil pump 50 to the power transmission mechanism 3, a third oil passage 13 that connects an oil discharge port 97 (oil suction port) provided in the case 9 to the oil pump 50, and an electromagnetic control valve 88 (switching valve 8) that switches the distribution path of the oil discharged from the oil pump 50. When the rotation speed of the output member 33 is higher than a reference speed, the electromagnetic control valve 88 (switching valve 8) distributes the oil discharged by the oil pump 50 to both the first oil passage 11 and the second oil passage 12, and when the rotation speed of the output member 33 is equal to or lower than the reference speed, the electromagnetic control valve 88 (switching valve 8) distributes the oil discharged by the oil pump 50 to the first oil passage 11 without distributing it to the second oil passage 12. The oil cooler 7 is provided in the third oil passage 13.

[0033] Furthermore, the switching valve 8 is not limited to the electromagnetic control valve 88 as long as it is a control valve. For example, the control valve can be a pressure valve. Instead of the electromagnetic control valve 88, a pressure valve that opens when the hydraulic pressure is high and closes when the hydraulic pressure is low can be used. By disposing a pressure valve that opens when the hydraulic pressure is high and closes when the hydraulic pressure is low, oil can be supplied to both the rotating electric machine 2 and the power transmission mechanism 3 when the hydraulic pressure is high, and oil can be supplied to the rotating electric machine 2 but not to the power transmission mechanism 3 when the hydraulic pressure is low. The hydraulic pressure can be controlled, for example, by controlling the discharge force of the oil pump 50. In one aspect, when the rotation speed of the output member 33 is higher than a reference speed, the rotation state (rotation speed) of the oil pump 50 is set to a first rotation state (high rotation state), and when the rotation speed of the output member 33 is equal to or lower than the reference speed, the rotation state (rotation speed) of the oil pump 50 is set to a second rotation state (low rotation state lower than the high rotation state). Details of the type and configuration of the control valve will be omitted, but this does not preclude the first rotation state from being set to a low rotation state and the second rotation state from being set to a high rotation state.

[0034] In one embodiment, the switching between the first supply state and the second supply state is achieved by switching the rotation direction of the oil pump 50 and reversing the direction of oil discharge from the oil pump 50, as in a second configuration example shown in FIGS. 3 and 4 . The control device 6 controls at least the oil pump 50. As shown in FIG. 3 , in the first supply state, the control device 6 controls the oil pump 50 so that a drive source such as a pump motor of the oil pump 50 is in a first rotation state in which it rotates in a first rotation direction C1. This causes oil to be discharged from the first discharge port 51a of the oil pump 50. The first first oil passage 11a and the second oil passage 12 are connected to the first discharge port 51a via a first check valve 81 (switching valve 8). The first check valve 81 allows oil to flow from the first discharge port 51a toward the first first oil passage 11a and the second oil passage 12 and blocks oil from flowing in the opposite direction. When oil is discharged from the first discharge port 51a, the first check valve 81 allows the oil to flow. The first first oil passage 11a connects the first discharge port 51a and a first first oil inlet 98a provided in the first chamber 91, and oil is supplied to the rotating electric machine 2. The second oil passage 12 connects the first discharge port 51a and a second oil inlet 99, and oil is supplied to the power transmission mechanism 3.

[0035] A first oil discharge port 97a provided in the case 9 is connected to a first third oil passage 13a that leads to the second pump port 52 of the oil pump 50. The first oil discharge port 97a is connected to the first third oil passage 13a via a second check valve 82 (switching valve 8). The second check valve 82 allows oil to flow in the direction from the first oil discharge port 97a toward the first third oil passage 13a and blocks oil from flowing in the opposite direction. In a first supply state in which the second pump port 52 functions as a suction port (first suction port) of the oil pump 50, that is, in a first rotation state in which the oil pump 50 rotates in the first rotation direction C1, oil is sucked from an oil reservoir in the case 9 via the first oil discharge port 97a. The second check valve 82 allows oil to flow from the first oil discharge port 97a toward the second pump port 52, so that the oil pump 50 sucks oil from inside the case 9 via the first third oil passage 13a.

[0036] As shown in FIG. 4, in the second supply state, the control device 6 controls the drive source, such as a pump motor, of the oil pump 50 to enter a second rotation state in which the drive source rotates in a second rotation direction C2, which is opposite to the first rotation direction C1. This causes oil to be discharged from the second pump port 52 of the oil pump 50. In the second supply state, the second pump port 52 functions as a second discharge port. A second first oil passage 11b is connected to the second pump port 52. The second first oil passage 11b is connected to a second first oil inlet 98b provided in the first chamber 91 via a third check valve 83 (switching valve 8). The third check valve 83 allows oil to flow from the second pump port 52 (second discharge port) toward the second first oil inlet 98b and blocks oil from flowing in the opposite direction. When the second pump port 52 functions as a discharge port (second discharge port) of the oil pump 50, oil flows from the second pump port 52 (second discharge port) toward the second first oil inlet 98b. The third check valve 83 allows this oil to flow, so that oil is supplied from the oil pump 50 to the rotating electrical machine 2 via the second first oil passage 11b.

[0037] A second oil discharge port 97b provided in the case 9 is connected to a second third oil passage 13b that leads to a second suction port 51b of the oil pump 50. The second oil discharge port 97b is connected to the second third oil passage 13b via a fourth check valve 84 (switching valve 8). The fourth check valve 84 allows oil to flow from the second oil discharge port 97b toward the second third oil passage 13b and blocks oil flow in the opposite direction. When the oil pump 50 draws oil from the second suction port 51b, oil is sucked from an oil reservoir in the case 9 via the second oil discharge port 97b. The fourth check valve 84 allows oil to flow from the second oil discharge port 97b toward the second suction port 51b, so the oil pump 50 draws oil from the case 9 via the second third oil passage 13b.

[0038] That is, in the second configuration example, the oil supply device 5 includes an oil pump 50 that sucks in and discharges oil in the case 9, a control device 6 that controls the oil pump 50, a first oil passage 11 (first first oil passage 11a, second first oil passage 11b) that supplies the oil discharged by the oil pump 50 to the rotating electric machine 2, a second oil passage 12 that supplies the oil discharged by the oil pump 50 to the power transmission mechanism 3, a third oil passage 13 (first third oil passage 13a, second third oil passage 13b) that connects the oil discharge port 97 (oil intake port: first oil discharge port 97a, second oil discharge port 97b) provided in the case 9 to the oil pump 50, and a switching valve 8 (first check valve 81, second check valve 82, third check valve 83, fourth check valve 84) that switches the oil flow path depending on the rotation state of the oil pump 50. When the rotational state of the oil pump 50 is the first rotational state (first rotational direction C1), the switching valve 8 causes the oil discharged from the oil pump 50 to flow through both the first oil passage 11 (first first oil passage 11a) and the second oil passage 12. When the rotational state of the oil pump 50 is the second rotational state (second rotational direction C2), the switching valve 8 causes the oil discharged from the oil pump 50 to flow through the first oil passage 11 (second first oil passage 11b) rather than through the second oil passage 12. When the rotational speed of the output member 33 is higher than a reference speed, the control device 6 sets the rotational state of the oil pump 50 to the first rotational state (first rotational direction C1), and when the rotational speed of the output member 33 is equal to or lower than the reference speed, the control device 6 sets the rotational state of the oil pump 50 to the second rotational state (second rotational direction C2).

[0039] The oil cooler 7 is provided in the first oil passage 11 or the third oil passage 13. Specifically, when the oil pump 50 is in the first rotation state (first rotation direction C1), the oil cooler 7 is provided in the third oil passage 13 (first third oil passage 13a), and when the oil pump 50 is in the second rotation state (second rotation direction C2), the oil cooler 7 is provided in the first oil passage 11 (second first oil passage 11b). In FIGS. 3 and 4, the first oil discharge port 97a and the second oil discharge port 97b are illustrated as independent connection ports in the case 9, but the first oil discharge port 97a and the second oil discharge port 97b may be a common connection port (oil discharge port 97). The oil cooler 7 is provided between the second pump port 52 of the oil pump 50 and the oil discharge port 97 of the case 9, and the second cooler port 72 of the oil cooler 7 and the second pump port 52 of the oil pump 50 are connected by the connection oil passage 14.

[0040] As described above, the pump second port 52 functions as a suction port (first suction port) when the oil pump 50 is in the first rotational state (first rotational direction C1), and functions as a discharge port (second discharge port) when the oil pump 50 is in the second rotational state (second rotational direction C2). When the oil pump 50 is in the first rotational state (first rotational direction C1), the cooler second port 72 functions as an output port, and the connecting oil passage 14 functions as the third oil passage 13 (first third oil passage 13a) that connects the oil discharge port 97 of the case 9 and the oil pump 50 via the oil cooler 7. When the oil pump 50 is in the second rotational state (second rotational direction C2), the cooler second port 72 functions as an input port, and the connecting oil passage 14 functions as the first oil passage 11 (second first oil passage 11b) that supplies oil discharged from the oil pump 50 to the rotating electrical machine 2 via the oil cooler 7.

[0041] The first third oil passage 13a is an oil passage that extends from the oil discharge port 97 (first oil discharge port 97a) to the pump second port 52 (first suction port) via the first cooler first port 71a, the oil cooler 7, and the connecting oil passage 14. The second first oil passage 11b is an oil passage that extends from the pump second port 52 (second discharge port) to the second first oil inlet 98b via the connecting oil passage 14, the oil cooler 7, and the second cooler first port 71b. In FIGS. 3 and 4, the first cooler first port 71a and the second cooler first port 71b are illustrated as independent connection ports in the oil cooler 7, but they may be a common connection port (cooler first port 71).

[0042] When the cooler first port 71 functions as the first cooler first port 71a (input port), the second first oil passage 11b connected to the second cooler first port 71b is blocked by the third check valve 83. Therefore, air flows into the third oil passage 13 (first third oil passage 13a) via the second first oil passage 11b, and the oil pump 50 does not suck in the air. Furthermore, when the cooler first port 71 functions as the second cooler first port 71b (output port), the first third oil passage 13a connected to the first cooler first port 71a is blocked by the second check valve 82. Therefore, the oil discharged from the oil pump 50 does not flow back through the first third oil passage 13a and into the case 9.

[0043] 3 and 4, the first discharge port 51a and the second suction port 51b are illustrated as independent connection ports in the oil pump 50. However, the first discharge port 51a and the second suction port 51b may be a common connection port, in which case the single pump first port 51 functions as the first discharge port 51a and the second suction port 51b.

[0044] In the first supply state, when the pump first port 51 functions as the first discharge port 51a, oil may flow into the second third oil passage 13b connected to the second suction port 51b. However, because the fourth check valve 84 is provided between the second third oil passage 13b and the second oil discharge port 97b, oil does not flow into the case 9 from the second oil discharge port 97b.

[0045] In the second supply state, when the pump first port 51 functions as the second suction port 51b, negative pressure is applied to the first check valve 81, blocking the first first oil passage 11a and the second oil passage 12. Therefore, the oil pump 50 does not suck in air via the first first oil passage 11a or the second oil passage 12. In addition, the suction force of the oil pump 50 acts on the second third oil passage 13b and the second oil discharge port 97b, allowing oil to be appropriately sucked in.

[0046] Furthermore, the first oil inlet 98a and the second oil inlet 98b may also be configured as a common oil inlet 98.

[0047] In the present embodiment, the case 9 includes a first chamber 91 and a second chamber 92 that are partitioned from each other. A first oil reservoir 93 is formed in the first chamber 91, and a second oil reservoir 94 is formed in the second chamber 92. As described above, in the present embodiment, the oil supply device 5 is configured to be able to switch the oil supply state between a first supply state in which oil is supplied to both the rotating electric machine 2 and the power transmission mechanism 3, and a second supply state in which oil is supplied to the rotating electric machine 2 without supplying oil to the power transmission mechanism 3. This allows the temperature of the oil in the first oil reservoir 93 to be increased preferentially in the second supply state. However, in the second supply state, the temperature of the oil in the second oil reservoir 94 does not increase. Therefore, if the oil in the first oil reservoir 93 and the oil in the second oil reservoir 94 mix, the increase in the temperature of the oil due to heat exchange with the rotating electric machine 2 is limited. Therefore, the power consumed to generate heat in the stator coil 23 also increases, which may reduce the power consumption efficiency of the DC power supply.

[0048] Therefore, in the second supply state, the oil supply device 5 preferably does not draw oil from the second chamber 92 (oil from the second oil reservoir 94) but draws oil from the first chamber 91 (oil from the first oil reservoir 93) to supply oil to the rotating electric machine 2. By circulating the oil that cools and lubricates the rotating electric machine 2, the temperature of the oil can be easily raised quickly.

[0049] 2 to 4, an oil discharge port 97 (suction port) through which the oil pump 50 draws oil from the oil reservoir is provided in the first chamber 91. For example, a strainer is disposed in the first chamber 91, and the oil discharge port 97 is provided to draw oil from the first oil reservoir 93. The first oil reservoir 93 and the second oil reservoir 94 are communicated with each other by a communication passage 95 provided in a partition member such as a partition wall that separates the first chamber 91 and the second chamber 92. Therefore, the oil in the first oil reservoir 93 and the oil in the second oil reservoir 94 mix together. Note that the communication passage 95 is not limited to such an opening, and may be an oil passage formed in the wall of the case 9 or the like.

[0050] In this embodiment, the communication passage 95 is provided with a flow restricting portion 96, which allows the communication passage 95 to be blocked. The flow restricting portion 96 closes the communication passage 95 in a second supply state in which the oil supply device 5 supplies oil to the first chamber 91 but not to the second chamber 92, and opens the communication passage 95 in a first supply state in which the oil supply device 5 supplies oil to both the first chamber 91 and the second chamber 92. FIGS. 2 to 4 illustrate an example in which the flow restricting portion 96 is configured as a butterfly plate, which is a swingable lid-like member. The butterfly plate blocks the communication passage 95 when the hydraulic pressure in the first oil reservoir 93 is higher than the hydraulic pressure in the second oil reservoir 94. The butterfly plate opens the communication passage 95 when the hydraulic pressures in the first oil reservoir 93 and the second oil reservoir 94 are approximately equal or when the hydraulic pressure in the second oil reservoir 94 is higher. The flow restricting portion 96 is not limited to a butterfly plate, and may be configured as a check valve or a control valve.

[0051] The oil supply device 5 can be configured to include the above-described first oil passage 11, second oil passage 12, third oil passage 13, oil pump 50, first oil reservoir 93, second oil reservoir 94, flow restriction unit 96, and control device 6. The oil supply device 5 may further include an oil cooler 7. As described above, in the first supply state, the oil supply device 5 can appropriately cool and lubricate the rotating electric machine 2 and the power transmission mechanism 3 with oil. Furthermore, when waste heat utilization is required, the oil supply device 5 can quickly increase the temperature of the oil so that waste heat can be utilized via the oil with higher utilization efficiency.

[0052] The following briefly summarizes aspects of the above-described vehicle drive device (1).

[0053] In one aspect, the vehicle drive device (1) includes a rotating electric machine (2), an output member (33) drivingly connected to wheels (4), a power transmission mechanism (3) that transmits power between the rotating electric machine (2) and the output member (33), a case (9) that houses the rotating electric machine (2) and the power transmission mechanism (3), and an oil supply device (5) that can supply oil to multiple locations within the case (9), wherein the oil supply device (5) supplies oil to both the rotating electric machine (2) and the power transmission mechanism (3) when the rotational speed of the output member (33) is higher than a predetermined reference speed, and does not supply oil to the power transmission mechanism (3) when the rotational speed of the output member (33) is equal to or lower than the reference speed, and supplies oil to the rotating electric machine (2) without supplying oil to the power transmission mechanism (3).

[0054] According to this configuration, when the rotational speed of the output member (33) is higher than the reference speed, it is possible to appropriately cool and lubricate both the rotating electric machine (2) and the power transmission mechanism (3), which require cooling and lubrication. On the other hand, when the rotational speed of the output member (33) is equal to or lower than the reference speed, oil is not supplied to the power transmission mechanism (3), which does not require cooling and lubrication as much. This allows the rotating electric machine (2) to be appropriately cooled and lubricated and the oil temperature to be efficiently increased. In other words, according to this configuration, it is possible to appropriately cool and lubricate the vehicle drive device (1) using oil and to utilize waste heat via the oil with higher utilization efficiency.

[0055] In addition, it is preferable that the vehicle drive device (1) has a case (9) that has a first chamber (91) and a second chamber (92) that are partitioned from each other, the rotating electric machine (2) is accommodated in the first chamber (91), and at least a part of the power transmission mechanism (3) is accommodated in the second chamber (92), and when the rotation speed of the output member (33) is equal to or lower than the reference speed, the oil supply device (5) does not suck oil from the second chamber (92), but sucks oil from the first chamber (91) and supplies oil to the rotating electric machine (2).

[0056] According to this configuration, when oil is not supplied to the power transmission mechanism (3), the oil in the first chamber (91) that has cooled and lubricated the rotating electric machine (2) is repeatedly supplied to the rotating electric machine (2). Therefore, the rotating electric machine (2) can be appropriately cooled and lubricated, and the temperature of the oil can be efficiently increased.

[0057] In addition, it is preferable that the vehicle drive device (1) is configured such that an oil intake port (97) of the oil supply device (5) is arranged to open to the first chamber (91), and the case (9) includes a communication passage (95) that communicates between a first oil reservoir (93) that is an oil reservoir formed in the first chamber (91) and a second oil reservoir (94) that is an oil reservoir formed in the second chamber (92), and a flow restricting part (96), and that the flow restricting part (96) is configured to close the communication passage (95) when the oil supply device (5) is not supplying oil to the second chamber (92) but is supplying oil to the first chamber (91), and to open the communication passage (95) when the oil supply device (5) is supplying oil to both the first chamber (91) and the second chamber (92).

[0058] This configuration makes it possible to appropriately control the flow of oil between the first oil reservoir (93) and the second oil reservoir (94).

[0059] In the vehicle drive device (1), the oil supply device (5) includes an oil pump (50) that sucks in and discharges oil from the case, a control device (6) that controls the oil pump (50), a first oil passage (11) that supplies the oil discharged from the oil pump (50) to the rotating electric machine (2), a second oil passage (12) that supplies the oil discharged from the oil pump (50) to the power transmission mechanism (3), a third oil passage (13) that connects an oil suction port (97) provided in the case (9) to the oil pump (50), and a switching valve (8) that switches an oil flow path depending on a rotation state of the oil pump (50), and the switching valve (8) switches the oil flow path depending on a rotation state of the oil pump (50), When the rotational state of the oil pump (50) is in the state (C1), the oil discharged from the oil pump (50) is circulated to both the first oil passage (11) and the second oil passage (12), and when the rotational state of the oil pump (50) is in the second rotational state (C2), the oil discharged from the oil pump (50) is circulated to the first oil passage (11) without circulating to the second oil passage (12), and it is preferable that the control device (6) sets the rotational state of the oil pump (50) to the first rotational state (C1) when the rotational speed of the output member (33) is higher than the reference speed, and sets the rotational state of the oil pump (50) to the second rotational state (C2) when the rotational speed of the output member (33) is equal to or lower than the reference speed.

[0060] According to this configuration, by controlling the rotation state of the oil pump (50), it is possible to switch, with a simple configuration, between supplying oil to both the rotating electric machine (2) and the power transmission mechanism (3), or supplying oil to the rotating electric machine (2) without supplying oil to the power transmission mechanism (3). [Explanation of symbols]

[0061] 1: Vehicle drive device, 2: Rotating electric machine, 3: Power transmission mechanism, 4: Wheel, 5: Oil supply device, 6: Control device, 7: Oil cooler (heat exchanger), 8: Switching valve, 9: Case, 11: First oil passage, 12: Second oil passage, 13: Third oil passage, 33: Output member, 50: Oil pump, 91: First chamber, 92: Second chamber, 93: First oil reservoir, 94: Second oil reservoir, 95: Communication passage, 96: Flow restriction section, 97: Oil outlet (oil intake port), C1: First rotation direction (first rotation state), C2: Second rotation direction (second rotation state)

Claims

1. A rotating electric machine, an output member drivingly connected to the wheels; a power transmission mechanism that transmits power between the rotating electric machine and the output member; a case that accommodates the rotating electric machine and the power transmission mechanism; an oil supply device capable of supplying oil to a plurality of locations within the case; A vehicle drive device comprising: The oil supply device is When the rotation speed of the output member is higher than a predetermined reference speed, oil is supplied to both the rotating electric machine and the power transmission mechanism; When the rotation speed of the output member is equal to or lower than the reference speed, the vehicle drive device supplies oil to the rotating electric machine without supplying oil to the power transmission mechanism.

2. the case includes a first chamber and a second chamber that are partitioned from each other; The rotating electric machine is accommodated in the first chamber, and at least a part of the power transmission mechanism is accommodated in the second chamber, 2. The vehicle drive device according to claim 1, wherein when the rotational speed of the output member is equal to or lower than the reference speed, the oil supply device does not draw oil from the second chamber, but draws oil from the first chamber and supplies oil to the rotating electric machine.

3. an oil suction port for the oil supply device is provided so as to open into the first chamber; the case includes a communication passage that communicates a first oil reservoir that is a reservoir for oil formed in the first chamber with a second oil reservoir that is a reservoir for oil formed in the second chamber, and a flow restriction portion; 3. The vehicle drive device according to claim 2, wherein the flow restricting portion is configured to close the communication passage when the oil supply device does not supply oil to the second chamber but supplies oil to the first chamber, and to open the communication passage when the oil supply device supplies oil to both the first chamber and the second chamber.

4. The oil supply device is an oil pump that sucks in and discharges oil from the case; a control device for controlling the oil pump; a first oil passage that supplies oil discharged by the oil pump to the rotary electric machine; a second oil passage that supplies oil discharged by the oil pump to the power transmission mechanism; a third oil passage connecting an oil intake port provided in the case and the oil pump; a switching valve that switches the oil flow path depending on the rotation state of the oil pump, The switching valve is When the rotation state of the oil pump is a first rotation state, the oil discharged by the oil pump is circulated through both the first oil passage and the second oil passage, When the rotation state of the oil pump is the second rotation state, the oil discharged by the oil pump is not circulated to the second oil passage but is circulated to the first oil passage, The control device When the rotation speed of the output member is higher than the reference speed, the rotation state of the oil pump is set to the first rotation state, The vehicle drive device according to claim 1 , wherein when the rotation speed of the output member is equal to or lower than the reference speed, the rotation state of the oil pump is set to the second rotation state.

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