Integrated electromechanical unit

Abstract

This technology provides a way to suppress the decrease in motor cooling efficiency in an integrated electromechanical unit. [Solution] The electromechanical unit for a vehicle comprises a housing having a first chamber and a second chamber located above the first chamber; a motor located in the first chamber; an oil passage located in the first chamber and having a discharge port for discharging oil from above the motor to the motor; an electrical circuit unit located in the second chamber; a cooler located in the second chamber for cooling the electrical circuit unit; and a branched cooling passage branched from a cooling passage that supplies refrigerant to the cooler, wherein at least a portion of the branched cooling passage is located in the first chamber and near the oil passage.

Description

Technical Field

[0001] The technology disclosed in this specification relates to an electromechanical unit for vehicles.

Background Art

[0002] Patent Document 1 discloses an electromechanical unit for a vehicle, which includes a housing having a first chamber and a second chamber, a motor disposed in the first chamber, an electric circuit unit disposed in the second chamber, and a cooler for cooling the electric circuit unit.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In such an electromechanical unit, in order to cool the motor disposed in the first chamber, an oil passage through which lubricating oil flows may be disposed above the motor, and a structure may be adopted in which the lubricating oil is discharged from a discharge port formed in the oil passage to the motor.

[0005] However, the oil passage disposed above the motor extends in the upper part of the first chamber and is disposed near the second chamber where the electric circuit unit is provided. Therefore, there is a concern that the temperature of the lubricating oil flowing through the oil passage rises due to heat received from the electric circuit unit, and the cooling efficiency of the motor decreases. This specification provides a technology for suppressing a decrease in the cooling efficiency of the motor in the electromechanical unit.

Means for Solving the Problems

[0006] The electromechanical unit for a vehicle disclosed herein may include a housing having a first chamber and a second chamber located above the first chamber; a motor located in the first chamber; an oil passage located in the first chamber and having a discharge port for discharging oil from above the motor to the motor; an electrical circuit unit located in the second chamber; a cooler located in the second chamber for cooling the electrical circuit unit; and a branched cooling passage branched from a cooling passage that supplies refrigerant to the cooler. The branched cooling passage may be located in the first chamber and near the oil passage. Here, the range of “near the oil passage” may include any position where, when the branched cooling passage is located in the first chamber, the temperature of the oil flowing through the oil passage is lower than when there is no branched cooling passage.

[0007] In the above-described electromechanical unit, a branched cooling channel is provided in the first chamber near the oil passage. As a result, the oil flowing through the oil passage is cooled, thereby suppressing a decrease in the motor's cooling efficiency. [Brief explanation of the drawing]

[0008] [Figure 1] A schematic diagram showing the configuration of an integrated electromechanical unit. [Figure 2] This diagram shows a view of the motor from above, illustrating an example of the arrangement of the motor, oil passage, and second cooling passage located in the first chamber. [Figure 3] This figure schematically shows a cross-sectional view along line III-III in Figure 2. [Figure 4] This diagram shows a view of the motor from above, illustrating an example of the arrangement of the motor, oil passage, and second cooling passage located in the first chamber. [Figure 5] This diagram shows a view of the motor from above, illustrating an example of the arrangement of the motor, oil passage, and second cooling passage located in the first chamber. [Modes for carrying out the invention]

[0009] The electromechanical unit 10 for vehicles will be described below with reference to the drawings. The electromechanical unit 10 is mounted on a vehicle that has a driving motor. Such a vehicle is not particularly limited, but may be, for example, a hybrid vehicle, an electric vehicle, or a fuel cell vehicle. Some or all of the technologies described in this embodiment can also be similarly applied to vehicles that travel on tracks. Furthermore, the vehicle is not limited to those operated by a user, but may be remotely controlled by an external device or be autonomous.

[0010] Here, each direction of the electromechanical unit 10 in the drawing corresponds to the direction when mounted on the vehicle, i.e., the direction of the vehicle. Therefore, direction FR indicates the front in the longitudinal direction of the vehicle, and direction RR indicates the rear in the longitudinal direction of the vehicle. Direction LH indicates the left in the lateral direction of the vehicle, and direction RH indicates the right in the lateral direction of the vehicle. Direction UP indicates the upward direction in the vertical direction of the vehicle, and direction DW indicates the downward direction in the vertical direction of the vehicle.

[0011] As shown in Figure 1, the electromechanical unit 10 includes a housing 12, which is a housing member. The housing 12 comprises a housing body 14 and a cover plate 16. The housing body 14 has a bottom wall 14a, four side walls 14b extending upward from the outer peripheral edge of the bottom wall 14a, and a partition wall 14w. An opening 14c is formed at the top of the housing body 14, defined by the four side walls 14b. The cover plate 16 is attached to the opening 14c of the housing body 14, and the opening 14c of the housing body 14 is closed by the cover plate 16. The partition wall 14w is provided inside the housing 12 and divides the inside of the housing 12 into a first chamber R1 and a second chamber R2. The second chamber R2 is located above the first chamber R1. The housing body 14 is not particularly limited, but may be made of a metal material such as aluminum. The cover plate 16 is a plate-shaped component and is not particularly limited, but may be made of a metal material such as aluminum.

[0012] The electromechanical unit 10 further comprises a plurality of motors 18, 20 and a plurality of gear mechanisms 22, 24, 26, 28. The plurality of motors 18, 20 include a first motor 18 and a second motor 20. The first motor 18 and the second motor 20 are arranged in a first chamber R1. The second motor 20 may, for example, be positioned behind the first motor 18, although this is not particularly limited. Also, at least a portion of the second motor 20 may, for example, be positioned above the first motor 18, although this is not particularly limited. The plurality of gear mechanisms 22, 24, 26, 28 are arranged in the first chamber R1. The plurality of gear mechanisms 22, 24, 26, 28 include a planetary gear mechanism 22, a reduction gear mechanism 24, a motor output gear mechanism 26, and a differential gear mechanism 28. The motor output gear mechanism 26 is connected to the second motor 20 via an axle. This allows the vehicle to transmit power from the second motor 20 to the wheels via the motor output gear mechanism 26. Note that the number of motors 18 and 20 is not necessarily limited to two; at least one is sufficient. Similarly, the number of gear mechanisms 22, 24, 26, and 28 is not necessarily multiple; at least one is sufficient.

[0013] The electromechanical unit 10 further includes an electrical circuit unit 30. The electrical circuit unit 30 is located in the second chamber R2. The electrical circuit unit 30, also called a PCU (Power Control Unit), converts power from a high-voltage battery mounted on the vehicle from DC to AC and supplies it to the first motor 18 and the second motor 20. The electrical circuit unit 30 has a first electrical circuit unit 30a and a second electrical circuit unit 30b. The second electrical circuit unit 30b is located below the first electrical circuit unit 30a. The first electrical circuit unit 30a is not particularly limited, but may be fixed to, for example, the cover plate 16 of the housing 12. The second electrical circuit unit 30b is not particularly limited, but may be fixed to, for example, the housing body 14.

[0014] The first electrical circuit unit 30a is not particularly limited, but may include, for example, a boost converter circuit and an inverter circuit. These boost converter circuit and inverter circuit are composed of a plurality of switching elements. The plurality of switching elements are controlled by a control board 62 provided on the upper surface of the cover plate 16, and convert the power from the high-voltage battery from DC to AC. A protective cover 64 is provided on the cover plate 16 so as to cover the control board 62.

[0015] The second electrical circuit unit 30b is not particularly limited, but may, for example, have a reactor and a step-down converter. The reactor is also a component of the step-up converter circuit of the first electrical circuit unit 30a. The step-down converter is electrically connected between the high-voltage battery and the auxiliary battery and can step down the DC power from the high-voltage battery and supply it to the auxiliary battery. The auxiliary battery is connected to various control systems and other auxiliary equipment of the vehicle and supplies power to them.

[0016] The electromechanical unit 10 further includes a cooler 42, a cooling channel 44, and a branched cooling channel 46. The cooler 42 is located in the second chamber R2. The cooler 42 recovers heat from the electrical circuit unit 30 and cools the electrical circuit unit 30. The cooler 42 is not particularly limited, but for example, it may be provided in correspondence with the first electrical circuit unit 30a of the electrical circuit unit 30 and configured to cool the boost converter circuit and inverter circuit of the first electrical circuit unit 30a. Alternatively, the cooler 42 may be provided in correspondence with the second electrical circuit unit 30b, or it may be provided in correspondence with both the first electrical circuit unit 30a and the second electrical circuit unit 30b. The cooling channel 44 supplies a refrigerant (e.g., water) to the cooler 42. A radiator and a refrigerant pump provided outside the housing 12 are connected to the cooling channel 44. When the refrigerant pump is activated, the refrigerant circulates between the cooler 42 and the radiator via the cooling passage 44.

[0017] The branched cooling channel 46 is a channel that branches off from the cooling channel 44 and is configured to pass through the first chamber R1 and return to the cooling channel 44. The branched cooling channel 46 is not particularly limited, but for example, it may be a channel connected in parallel to the cooler 42 among the circulation channels that make up the cooling channel 44. In this example, the branching point of the cooling channel 44 and the branched cooling channel 46 is provided outside the housing body 14. Alternatively, the branching point of the cooling channel 44 and the branched cooling channel 46 may be provided inside the housing body 14, for example, inside the first chamber R1.

[0018] The electromechanical unit 10 further includes a plurality of oil passages 52, 54. The plurality of oil passages 52, 54 include a first oil passage 52 and a second oil passage 54. The first oil passage 52 and the second oil passage 54 are located in the first chamber R1. The first oil passage 52 is located above the first motor 18 and cools the first motor 18 by discharging lubricating oil toward the first motor 18 from its discharge port. The second oil passage 54 is located above the second motor 20 and cools the second motor 20 by discharging lubricating oil toward the second motor 20 from its discharge port. The first oil passage 52 and the second oil passage 54 are connected to an oil cooler and an oil pump located outside the housing 12. When the oil pump is operating, lubricating oil cooled by the oil cooler is supplied to the first oil passage 52 and the second oil passage 54.

[0019] Figure 2 shows the positional relationship between the multiple motors 18 and 20, the multiple oil passages 52 and 54, and the branched cooling passage 46. Figure 3 shows a schematic representation of the configuration of the first motor 18 and the first oil passage 52. The configuration of the second motor 20 and the second oil passage 54 is the same as that of the first motor 18 and the first oil passage 52, and therefore its explanation is omitted. The symbols assigned to the second motor 20 and the second oil passage 54 follow the same rules as those assigned to the first motor 18 and the first oil passage 52. The dashed arrows in the drawings indicate the flow of refrigerant through the branched cooling passage 46 and lubricating oil through the multiple oil passages 52 and 54.

[0020] The first motor 18 has a stator core 72, a stator coil 74, a central shaft 76, and a rotor 78. The stator core 72 has a structure extending cylindrically along the axial direction, and is formed by laminating a plurality of electromagnetic steel sheets. The stator coil 74 is an aggregate of coil strands constituting a plurality of coils. Each of the plurality of coils is wound so as to surround the corresponding one of the plurality of teeth formed on the inner peripheral surface of the stator core 72. Both ends of the stator coil 74 in the axial direction protrude from the stator core 72, and are particularly referred to as coil ends. The rotor 78 is fixed to the central shaft 76 and is formed by laminating a plurality of electromagnetic steel sheets. The central shaft 76 and the rotor 78 are disposed within the central hole portion of the stator core 72 and are rotatably supported about the axis of the first motor 18.

[0021] The first oil passage 52 is a pipeline for discharging lubricating oil to the first motor 18. The first oil passage 52 extends along the axial direction of the first motor 18 above the first motor 18. In this example, one first oil passage 52 is disposed with respect to the first motor 18. Instead of this example, a plurality of oil passages extending along the axial direction of the first motor 18 may be disposed apart from each other in the circumferential direction of the first motor 18.

[0022] The first oil passage 52 has a plurality of discharge ports 52a, 52b, 52c. The plurality of discharge ports 52a, 52b, 52c includes a first discharge port 52a, a second discharge port 52b, and a third discharge port 52c. The first discharge port 52a is the discharge port provided on the most upstream side among the plurality of discharge ports 52a, 52b, 52c, and is arranged at a position where lubricating oil is discharged toward one coil end of the stator coil 74. The third discharge port 52c is the discharge port provided on the most downstream side among the plurality of discharge ports 52a, 52b, 52c, and is arranged at a position where lubricating oil is discharged toward the other coil end of the stator coil 74. The second discharge port 52b is the discharge port provided between the first discharge port 52a and the third discharge port 52c, and is arranged at a position where lubricating oil is discharged toward the stator core 72. Note that the number and position of the discharge ports formed in the first oil passage 52 are not limited to this example, and various modes capable of cooling the first motor 18 may be adopted.

[0023] As shown in FIGS. 1 and 2, the branch cooling flow path 46 extends in the first chamber R1 so as to pass near each of the first oil passage 52 and the second oil passage 54. In this example, the branch cooling flow path 46 extends along a direction (the longitudinal direction of the vehicle) orthogonal to the extending direction (the left - right direction of the vehicle) of the plurality of oil passages 52, 54. The branch cooling flow path 46 extends above the plurality of oil passages 52, 54, that is, between the partition wall 14w of the housing main body 14 and the plurality of oil passages 52, 54. In this example, the branch cooling flow path 46 is in contact with the surfaces of the oil passages 52, 54. The branch cooling flow path 46 is in contact with the first oil passage 52 on the upstream side of the first discharge port 52a arranged at the most upstream of the first oil passage 52, and is in contact with the second oil passage 54 on the upstream side of the first discharge port 54a arranged at the most upstream of the second oil passage 54. The branch cooling flow path 46 and the plurality of oil passages 52, 54 may be formed of a metal material such as aluminum and integrally formed.

[0024] Multiple oil passages 52 and 54, positioned above the multiple motors 18 and 20, extend to the upper part of the first chamber R1. Heat radiated from the electrical circuit unit 30 in the second chamber R2 is transferred to the upper part of the first chamber R1. As a result, there is a concern that the temperature of the lubricating oil flowing through the multiple oil passages 52 and 54 will rise due to the heat received from the electrical circuit unit 30, reducing the cooling efficiency of the multiple motors 18 and 20.

[0025] In this embodiment, branched cooling channels 46 are provided within the first chamber R1 near multiple oil passages 52 and 54. As a result, the lubricating oil flowing through the multiple oil passages 52 and 54 is cooled, thereby suppressing a decrease in the cooling efficiency of the multiple motors 18 and 20.

[0026] The branched cooling channel 46 is positioned between the electrical circuit unit 30 and the multiple oil passages 52 and 54. This allows the branched cooling channel 46 to suppress the transfer of heat dissipated from the electrical circuit unit 30 to the multiple oil passages 52 and 54. In addition, the branched cooling channel 46 is in contact with the oil passages 52 and 54. This allows the lubricating oil flowing through the multiple oil passages 52 and 54 to be cooled efficiently.

[0027] Furthermore, the branched cooling channel 46 is in contact with each of the multiple oil passages 52 and 54 upstream of the first discharge ports 52a and 54a, which are located at the uppermost reaches of each of the multiple oil passages 52 and 54. This allows the lubricating oil to be cooled before it is discharged to the multiple motors 18 and 20, thereby suppressing a decrease in the cooling efficiency of the multiple motors 18 and 20.

[0028] As shown in Figure 4, the branched cooling channel 46 may have a plurality of parallel cooling channels 48a, 48b, and 48c. The plurality of parallel cooling channels 48a, 48b, and 48c are channels that have been re-branched from the branched cooling channel 46, and include a first parallel cooling channel 48a, a second parallel cooling channel 48b, and a third parallel cooling channel 48c. In this example, each of the plurality of parallel cooling channels 48a, 48b, and 48c extends parallel to each other. Alternatively, at least one of the plurality of parallel cooling channels 48a, 48b, and 48c may extend non-parallel to the other channels. The first parallel cooling channel 48a, the second parallel cooling channel 48b, and the third parallel cooling channel 48c are arranged in this order from upstream to downstream of each of the plurality of oil passages 52 and 54.

[0029] The first parallel cooling channel 48a is in contact with each of the oil passages 52 and 54 upstream of the first discharge ports 52a and 54a located at the uppermost reaches of each of the oil passages 52 and 54. The second parallel cooling channel 48b is in contact with each of the oil passages 52 and 54 between the first discharge ports 52a and 54a and the second discharge ports 52b and 54b of each of the oil passages 52 and 54. The third parallel cooling channel 48c is in contact with each of the oil passages 52 and 54 between the second discharge ports 52b and 54b and the third discharge ports 52c and 54c of each of the oil passages 52 and 54. Thus, the number of parallel cooling channels 48a, 48b, and 48c may be the same as the number of discharge ports formed in each of the oil passages 52 and 54. In this embodiment, a larger area of ​​the branched cooling channel 46 is located near each of the multiple oil passages 52 and 54, so that the lubricating oil flowing through each of the multiple oil passages 52 and 54 can be efficiently cooled.

[0030] As shown in Figure 5, the branched cooling channel 46 may have a plurality of parallel cooling channels 49a, 49b. The plurality of parallel cooling channels 49a, 49b are channels obtained by further branching the branched cooling channel 46, and include a first parallel cooling channel 49a and a second parallel cooling channel 49b. The first parallel cooling channel 49a extends parallel to the first oil channel 52 and is in contact with the first oil channel 52 at least from an upstream position of the first discharge port 52a to the position of the third discharge port 52c. The first parallel cooling channel 49a may overlap with the first oil channel 52 such that the first oil channel 52 is hidden when viewed from above the first motor 18. The second parallel cooling channel 49b extends parallel to the second oil channel 54 and is in contact with the second oil channel 54 at least from an upstream position of the first discharge port 54a to the position of the third discharge port 54c. The second parallel cooling channel 49b may overlap with the second oil channel 54 so that it is hidden when viewed from above the second motor 20. In this embodiment, a larger area of ​​the branched cooling channel 46 is located near each of the multiple oil channels 52 and 54, so that the lubricating oil flowing through each of the multiple oil channels 52 and 54 can be efficiently cooled.

[0031] The embodiments disclosed herein are summarized below. Note that the technical elements described below are independent technical elements that exhibit technical usefulness individually or in various combinations.

[0032] (Aspect 1) The electromechanical unit for a vehicle comprises a housing having a first chamber and a second chamber located above the first chamber; a motor located in the first chamber; an oil passage located in the first chamber and having a discharge port for discharging oil from above the motor to the motor; an electrical circuit unit located in the second chamber; a cooler located in the second chamber for cooling the electrical circuit unit; and a branched cooling passage branched from a cooling passage that supplies refrigerant to the cooler, wherein at least a portion of the branched cooling passage is located in the first chamber and near the oil passage.

[0033] (Aspect 2) The electromechanical unit according to embodiment 1, wherein at least a portion of the branched cooling channel is located between the electrical circuit unit and the oil passage.

[0034] (Aspect 3) The electromechanical unit according to embodiment 1 or 2, wherein at least a portion of the branched cooling channel is in contact with the oil passage.

[0035] (Aspect 4) The electromechanical unit according to any one of embodiments 1 to 3, wherein the oil passage extends above the motor along the axial direction of the motor, and at least a portion of the branched cooling passage is located upstream of the discharge port of the oil passage and near the oil passage.

[0036] (Appendix 5) The electromechanical unit according to any one of embodiments 1 to 4, wherein the branched cooling channel has a plurality of parallel cooling channels, and at least a portion of each of the plurality of parallel cooling channels is located near the oil passage.

[0037] (Aspect 6) The mechatronics unit according to any one of embodiments 1 to 5, wherein the branched cooling channel has a parallel cooling channel that extends parallel to the oil channel, and the parallel cooling channel is located near the oil channel.

[0038] Although several specific examples have been described in detail above, these are merely illustrative and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes to the specific examples illustrated above. The technical elements described in this specification or in the drawings exhibit technical usefulness individually or in combination. [Explanation of Symbols]

[0039] 10: Mechatronics unit, 12: Housing, 14: Housing body, 14a: Bottom wall, 14b: Side wall, 14c: Opening, 4w: Partition wall, 18: First motor, 20: Second motor, 22: Planetary gear mechanism, 24: Reduction gear mechanism, 26: Motor output gear mechanism, 28: Differential gear mechanism, 30: Electrical circuit unit, 42: Cooler, 44: Cooling channel, 46: Branch cooling channel, 52: First oil channel, 54: Second oil channel

Claims

1. An integrated electromechanical unit for vehicles, A housing having a first room and a second room located above the first room, A motor located in the first chamber, An oil passage is located in the first chamber and has a discharge port for discharging oil from above the motor to the motor, An electrical circuit unit located in the second chamber, A cooler is located in the second chamber and cools the electrical circuit unit, The cooler is equipped with a branched cooling channel that is branched off from the cooling channel that supplies refrigerant to the cooler, At least a portion of the branched cooling channel is a mechatronic unit located in the first chamber and near the oil passage.

2. The electromechanical unit according to claim 1, wherein at least a portion of the branched cooling channel is located between the electrical circuit unit and the oil passage.

3. The electromechanical unit according to claim 1, wherein at least a portion of the branched cooling channel is in contact with the oil passage.

4. The oil passage extends above the motor along the axial direction of the motor. The electromechanical unit according to any one of claims 1 to 3, wherein at least a portion of the branched cooling channel is located upstream of the discharge port of the oil passage and near the oil passage.

5. The aforementioned branched cooling channel has a plurality of parallel cooling channels, The electromechanical unit according to claim 1, wherein at least a portion of each of the plurality of parallel cooling channels is located near the oil passage.

6. The aforementioned branched cooling channel has a parallel cooling channel that extends parallel to the oil channel, The electromechanical unit according to claim 1, wherein the parallel cooling channel is located near the oil passage.

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