Electric drive unit with motor assembly isolated from beam loads transmitted through housing assembly

Abstract

An electric drive unit has an electric motor, a differential assembly, a transmission that transmits rotational power between the electric motor and the differential assembly, a pair of half shafts drivingly coupled to an output member of the differential assembly, and a housing assembly in which the electric motor, the differential assembly, the transmission, and the half shafts are housed. The electric motor includes a stator, a rotor, and a motor housing that houses the stator and the rotor. The motor housing is fixedly coupled to the housing assembly. Bending loads transmitted through the motor housing are not transmitted through the electric motor.

Description

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 264743, filed December 1, 2021, the disclosure of which is incorporated herein by reference as if fully set forth herein. Technical Field

[0002] This disclosure relates to an electric drive unit having an electric motor assembly that is isolated from beam loads transmitted through the housing assembly of the electric drive unit. Background Technology

[0003] This section provides background information in connection with this disclosure, which is not necessarily prior art.

[0004] One approach to electrifying a vehicle's powertrain involves incorporating an electric motor into the electric drive unit, such that the motor's housing is also a structural element of the electric drive unit. More specifically, such a configuration longitudinally transmits beam loads (i.e., vertical loads that cause the beam axle to bend at one or more locations between a pair of driven wheels) through the electric motor. This configuration can help reduce the weight of the electric drive unit and / or allow for easier integration / encapsulation of the electric motor into the electric drive unit. While this approach is relatively common in the modern trend of vehicle electrification, we note some drawbacks.

[0005] One such disadvantage involves the cyclic application of bending stress to the components of the electric motor and considerations regarding the impact of fatigue on the durability of the electric drive unit. Another such disadvantage involves the risk of damage to components of the cooling system, such as pumps or heat exchangers, if mounted externally to the housing assembly of the electric drive unit. In this respect, there is a risk that such externally mounted components may be potentially damaged if they impact an object during operation of a vehicle equipped with an electric drive unit. Summary of the Invention

[0006] This section provides a general overview of this disclosure and is not a full disclosure of its entire scope or all of its features.

[0007] In one embodiment, this disclosure provides an electric drive unit including a housing assembly, a motor assembly, a transmission, a differential assembly, and a first output shaft member and a second output shaft member. The housing assembly defines an output shaft axis and includes a first end cap, a second end cap, an intermediate housing member, a first shaft tube, and a second shaft tube. The first end cap has a first peripheral wall member and a first shaft tube mounting member. The first peripheral wall member defines a first cavity disposed around and extending longitudinally along the output shaft axis. The first shaft tube mounting member defines a first shaft tube bore. The second end cap has a second peripheral wall member and a second shaft tube mounting member. The second peripheral wall member defines a second cavity disposed around and extending longitudinally along the output shaft axis. The second shaft tube mounting member defines a second shaft tube bore. The intermediate housing member is disposed between and fixedly connected to the first and second end caps. The first shaft tube is received in the first shaft tube bore and fixedly connected to the first shaft tube mounting member. The second shaft tube is received in the second shaft tube bore and fixedly connected to the second shaft tube mounting member. The motor assembly has a motor housing, a stator, a rotor, and a motor output shaft. The motor housing is fixedly coupled to the intermediate housing member and extends into the first cavity. The motor housing is spaced apart from the first peripheral wall member and the first shaft tube mounting member. The motor housing defines a motor cavity in which the stator is disposed. The rotor is disposed in the stator to rotate relative to the stator about a motor axis. The motor output shaft is coupled to the rotor to rotate with the rotor. The motor output shaft extends through the intermediate housing member and into the second cavity. The transmission is disposed in the second cavity and includes a transmission input member and a transmission output member, the transmission input member being coupled to the motor output shaft to rotate with the motor output shaft, and the transmission output member being rotatable about the output axis. The differential assembly is disposed in the second cavity and includes a differential input member and a pair of differential output members, the differential input member being coupled to the transmission output members to rotate with the transmission output members. The first output shaft member is received in the first shaft tube and is rotatably coupled to the first of the pair of differential output members. The second output shaft member is received in the second shaft tube and is rotatably connected to the other of the pair of differential output members.

[0008] Further areas of applicability will become apparent from the description provided herein. The descriptions and specific examples in this overview are for illustrative purposes only and are not intended to limit the scope of this disclosure. Attached Figure Description

[0009] The accompanying drawings described herein are for illustrative purposes only, representing selected embodiments and not all possible implementations, and are not intended to limit the scope of this disclosure.

[0010] Figure 1 This is a perspective view of an exemplary electric drive unit constructed in accordance with the teachings of this disclosure;

[0011] Figure 2A and Figure 2B yes Figure 1 Exploded perspective view of the electric drive unit;

[0012] Figure 3 It is along Figure 1 A cross-sectional view taken from line 3-3;

[0013] Figure 4 It is a section taken along the rotation axis of the motor rotor. Figure 1 A cross-sectional view of the electric drive unit;

[0014] Figure 5 yes Figure 1 A front view of a portion of the electric drive unit, illustrating the intermediate housing component in more detail;

[0015] Figure 6 yes Figure 1 A front view of a portion of the electric drive unit, illustrating in more detail the intermediate housing component, motor housing, pump mount, and filter mount;

[0016] Figure 7 It is a cross-sectional view taken through the intermediate shell component;

[0017] Figure 8 yes Figure 4 The enlarged section provides a more detailed illustration of the motor controller of the motor assembly;

[0018] Figure 9 yes Figure 1 A perspective view of a portion of the electric drive unit, illustrating the transmission in more detail;

[0019] Figure 10 yes Figure 4 The enlarged portion illustrates the transmission and a portion of the lubrication and cooling system in more detail;

[0020] Figure 11 yes Figure 1 A perspective view of a portion of the electric drive unit, in which the first end cap is removed from the intermediate housing component to better illustrate the lubrication and cooling system;

[0021] Figure 12 It is intercepted through a part of the lubrication and cooling system. Figure 1A cross-sectional view of the electric drive unit is provided to illustrate the filter base and filter in more detail.

[0022] Figure 13 yes Figure 1 A perspective view of a portion of the electric drive unit, illustrating the motor assembly mounted to the intermediate housing component, as well as the lubrication and cooling system;

[0023] Figure 14 yes Figure 1 A cross-sectional view of a portion of the electric drive unit, illustrating the fluid connection between the heat exchanger of the lubrication and cooling system and the inverter of the motor assembly;

[0024] Figure 15 yes Figure 1 A cross-sectional view of a portion of the electric drive unit, illustrating the construction of the electric motor and the rotor heat exchanger of the lubrication and cooling system of the motor assembly;

[0025] Figure 16 yes Figure 1 A perspective view of a portion of the electric drive unit, illustrating the power connection ports and access ports within the housing assembly; and

[0026] Figure 17 yes Figure 1 A perspective view of a portion of the electric drive unit, in which a pair of cable leads and a passage cover are removed from the housing assembly to better illustrate the power connection port and passage port.

[0027] In the various views of the accompanying drawings, the corresponding reference numerals always indicate the corresponding parts. Detailed Implementation

[0028] refer to Figures 1 to 3 The electric drive unit constructed according to the teachings of this disclosure is generally indicated by reference numeral 10. The electric drive unit 10 may include a housing assembly 12, a motor assembly 14, a transmission 16, a differential assembly 18, a first output shaft assembly 20 and a second output shaft assembly 22, and a lubrication and cooling system 24.

[0029] The housing assembly 12 may define the output shaft 30 and may have a first end cap 32, a second end cap 34, an intermediate housing member 36, a first shaft tube 38, and a second shaft tube 40.

[0030] Refer to Figure 2 to Figure 4The first end cap 32 may have a first mounting flange 50, a first peripheral wall member 52, and a first shaft tube mount 54. The first mounting flange 50 may have a first abutment surface 60. The first peripheral wall member 52 may extend from the side of the first mounting flange 50 opposite to the first abutment surface 60 and may define a first cavity 62, which may be disposed around and extend longitudinally along the output axis 30. The first shaft tube mount 54 may be coupled to the end of the first peripheral wall member 52 opposite to the first mounting flange 50 and may close the first cavity 62. The first shaft tube mount 54 may include a first tubular protrusion 64 that defines a first shaft tube bore 66. The first shaft tube bore 66 may be concentrically disposed around the output axis 30.

[0031] The second end cap 34 may have a second mounting flange 70, a second peripheral wall member 72, and a second shaft tube mount 74. The second mounting flange 70 may have a second abutment surface 80. The second peripheral wall member 72 may extend from the side of the second mounting flange 70 opposite to the second abutment surface 80 and may define a second cavity 82, which may be disposed around and extend longitudinally along the output axis 30. The second shaft tube mount 74 may be coupled to the end of the second peripheral wall member 72 opposite to the second mounting flange 70 and may close the second cavity 82. The second shaft tube mount 74 may include a second tubular protrusion 84 that may define a second shaft tube bore 86. The second shaft tube bore 86 may be concentrically disposed around the output axis 30.

[0032] An intermediate housing member 36 is disposed between the first end cap 32 and the second end cap 34, and is fixedly connected to the first end cap 32 and the second end cap 34. In the provided example, the intermediate housing member 36 has a third abutment surface 90 and a fourth abutment surface 92 abutting against the first abutment surface 60 and the second abutment surface 80, respectively. A plurality of threaded fasteners 96 are fitted through holes (not specifically shown) in the first mounting flange 50 and the intermediate housing member 36, and are screwed into holes (not specifically shown) in the second mounting flange 70.

[0033] refer to Figures 5 to 7 The intermediate housing member 36 may have a first fluid conduit 100, a second fluid conduit 104, a third fluid conduit 108, and a fourth fluid conduit 110. The first fluid conduit 100 may define a coolant inlet 102, and the second fluid conduit 104 may define a coolant outlet 106. A plurality of transfer ports 114 may be formed through the intermediate housing member 36 to allow the first cavity 62 ( Figure 3 ) and the second cavity 82 ( Figure 3 Fluid communication between (China and the West).

[0034] return Figure 1 and Figure 3The first shaft tube 38 is received in the first shaft tube hole 66 and fixedly connected to the first shaft tube mounting member 54, while the second shaft tube 40 is received in the second shaft tube hole 86 and fixedly connected to the second shaft tube mounting member 74. In the provided example, the first shaft tube 38 and the second shaft tube 40 are press-fitted into the first shaft tube hole 66 and the second shaft tube hole 86, respectively, and a plurality of plug welds (not specifically shown) are provided in the plug weld orifices 120 formed through the first tubular protrusion 64 and the second tubular protrusion 84.

[0035] exist Figure 4 In this embodiment, the motor assembly 14 may include a motor 126 and a motor controller 128. The motor 126 may include a motor housing 130, a stator 132, a rotor 134, and a motor output shaft 136. The motor housing 130 is fixedly coupled to and extends from the intermediate housing member 36 into a first cavity 62. The motor housing 130 may be formed as a separate component fastened to the intermediate housing member 36, but in the provided example, the motor housing 130 is integrally and integrally formed with the intermediate housing member 36. The motor housing 130 is spaced apart from and does not contact the first peripheral wall member 52 or the first shaft tube mount 54. The motor housing 130 defines a motor cavity 140 in which the stator 132 is received. The stator 132 includes a stator body 144 and a plurality of windings 146. The stator body 144 defines a plurality of stator coolant channels 148. Figure 15 The rotor 134 is disposed in the stator 132 to rotate relative to the stator 132 about the motor axis 150. The motor output shaft 136 is coupled to the rotor 134 to rotate with it. The motor output shaft 136 extends through a shaft hole 154 and into a second cavity 82, which is formed through an intermediate housing member 36.

[0036] refer to Figure 8The motor controller 128 may include an inverter 160 configured to control the power supply to each winding 146 (phase) in the stator 132. Details of the inverter 160 can be found in co-pending U.S. Application No. 17 / 501,189, filed October 14, 2021, entitled “Electric Drive Module”; U.S. Provisional Application No. 63 / 209,588, filed June 11, 2021, entitled “Electric Drive Module Having Motor Control Unit with Inverter Mounted on Motor”; and U.S. Provisional Application No. 63 / 161,164, filed March 15, 2021, entitled “Electric Drive Unit”. In short, the inverter 160 includes an inverter mount 164, multiple buses 166, multiple heat-dissipating power semiconductors 168, and a circuit board assembly 170. Inverter mounting 164 is hermetically coupled to motor housing 130 and houses heat-dissipating power semiconductors 168, busbars 166, and circuit board assembly 170. Inverter mounting 164 includes a base 174 that isolates busbars 166 and circuit board assembly 170 from coolant channels 176. Busbars 166 include a positive busbar electrically connected to a power source, a ground busbar connected to an electrical ground, and multiple phase buses. Each phase busbar is electrically connected to one phase or set of windings 146 of stator 132. Each heat-dissipating power semiconductor 168 includes a power semiconductor 180 such as a MOSFET or IGBT and a heat sink 182 fixedly and thermally coupled to the power semiconductor 180. The power semiconductor 180 has a semiconductor chip 184 and multiple leads 186 electrically connected to the semiconductor chip 184. Semiconductor chip 184 and heat sink 186 are disposed in coolant channel 176, and lead 186 extends through base 174 of inverter mount 164 and is electrically connected to circuit board assembly 170 and bus 166. Inverter 160 is configured to control the amplitude and frequency of the power supplied to windings 146 of stator 132 to operate motor 126. More specifically, inverter 160 employs heat-dissipating power semiconductor 168 to control the switching of DC power to produce a three-phase AC output, wherein each phase of AC output is associated with a given winding 146 of stator 132.

[0037] exist Figure 1 , Figure 2B and Figure 3In this configuration, the differential assembly 18 can be configured in any desired manner to allow or selectively allow a speed difference between the first output shaft member 20 and the second output shaft member 22. Generally, the differential assembly 18 may include a differential input member 200 and a pair of differential output members 202. In the provided example, the differential assembly 18 is an open differential assembly comprising a bevel differential gear set, the differential input member 200 being a differential housing, and the differential output members 202 being side gears of the bevel differential gear set. However, it will be understood that any desired means of providing (or selectively providing) a speed difference between the pair of differential output members can be employed. In this regard, the differential assembly 18 may employ a helical differential gear set having paired meshing helical pinions, planetary (circular) gear sets, or one or more friction clutches, and / or may be configured to provide limited-slip, locking, and / or disengagement functions.

[0038] The differential assembly 18 can be received in the second cavity 82. A first differential bearing 206 can be received in a first differential bearing bore 208 formed in the second end cap 34, while a second differential bearing 210 can be received in a second differential bearing bore 212 formed in the intermediate housing member 36. The first differential bearing 206 and the second differential bearing 210 can support the differential input member 200 to rotate about the output axis 30 relative to the housing assembly 12. In the provided example, the first differential bearing 206 and the second differential bearing 210 are directly mounted to the differential input member 200 (i.e., the differential housing), but it will be understood that the first differential bearing 206 and the second differential bearing 210 can be mounted to an element of the transmission 16 or to an associated one of the first output shaft member 20 and the second output shaft member 22 to indirectly support the differential input member 200 to rotate about the output axis 30.

[0039] refer to Figure 2B , Figure 9 and Figure 10The transmission 16 can be configured in any desired manner to transmit rotational power between the motor output shaft 136 and the differential assembly 18. Generally, the transmission 16 includes a transmission input member 220 coupled to the motor output shaft 136 for rotation therewith, and a transmission output member 222 rotatable about an output shaft 30 and coupled to the differential input member 200 for rotation. In the provided example, the transmission input member 220 and the transmission output member 222 are helical gears, and the transmission 16 further includes a pair of compound gears 224. Each compound gear 224 includes a first intermediate gear 228 meshing with the transmission input member 220 and a second intermediate gear 230 coupled to the first intermediate gear 228 for rotation therewith and meshing with the transmission output member 222. Each compound gear 224 may optionally include a shaft 232 rotatably coupled to an associated compound gear 224. In the provided example, each shaft 232 is integrally formed with an associated second intermediate gear 230 and an associated first intermediate gear 228. However, it will be understood that one or both of the first intermediate gear 228 and the second intermediate gear 230 may be formed as discrete components assembled (e.g., press-fitted, welded) to the shaft 232.

[0040] like Figure 10 As best illustrated, a first end of each shaft 232 may be supported by a first bearing 240 mounted in a first bearing bore 242 formed in the intermediate housing member 36, while the opposite second end of each shaft 232 may be supported by a second bearing 244 mounted in a second bearing bore 246 formed in the second end cap 34. In the provided example, the second bearing bore 246 is formed through the second end cap 34, and a pair of bearing caps 250 are fixedly coupled to the second end cap 34 to close the end of the second bearing bore 246 opposite to the first bearing bore 242.

[0041] exist Figure 3In this configuration, the first output shaft member 20 is rotatably coupled to the first differential output member 202 and extends along the output axis 30 through the intermediate housing member 36 and the first end cap 32, extending into the first shaft tube 38. More specifically, the first output shaft member 20 extends through the first output shaft orifice 264, the first cavity 62, the second output shaft orifice 266, and the first tubular protrusion 64. The first output shaft orifice 264 is concentrically formed through the intermediate housing member 36 and the second differential bearing bore 212, and the second output shaft orifice 266 is formed through the wall of the first shaft tube mounting member 54 that closes the first cavity 62. The second output shaft member 22 is coupled to rotate with the second differential output member 202 and extends along the output axis 30 through the wall of the second shaft tube mounting member 74 that closes the second cavity 82, the second tubular protrusion 84, and the second shaft tube 40. If necessary, one or more bearings (not shown) may be used to support each of the first output shaft member 20 and the second output shaft member 22 for rotation about the output axis 30 relative to the housing assembly 12.

[0042] refer to Figure 3 , Figure 10 , Figure 11 and Figure 12 The lubrication and cooling system 24 may include a pump 290, a heat exchanger 292, a filter base 294, a filter 296, and an optional rotor heat exchanger 298. The pump 290 may be mounted to a pump mount 300, which is assembled into or incorporated into an intermediate housing member 36 within a first chamber 62 but offset from the motor housing 130. The suction inlet (not specifically shown) of the pump 290 may be fluidly connected to a suction conduit 308 in the pump mount 300, which may be formed through the intermediate housing member 36. Optionally, an inlet screen 310 may be fluidly connected to the end of the suction conduit 308 opposite to the pump 290. The inlet screen 310 may be fastened to the intermediate housing member 36 and may be disposed in a second chamber 82.

[0043] refer to Figure 6 , Figure 7 , Figure 11 and Figure 13The heat exchanger 292 can be configured to cool fluids used for lubricating and / or cooling various components of the electric drive unit 10. Any suitable type of heat exchanger can be used, but in the provided example, the heat exchanger 292 is a plate-and-frame heat exchanger having a first channel (not specifically shown) and a second channel 322 not in fluid communication with the first channel. The first channel is configured to carry a first fluid, such as a mixture of water and ethylene glycol, while the second channel 322 is configured to carry a second fluid, such as an oil-based fluid used for lubricating and cooling various components of the electric drive unit 10. The first channel may have an inlet and an outlet, the inlet being fluidly connected to the outlet 100a of the first fluid conduit 100 to receive the flow of the first fluid, and the outlet being fluidly connected to the inlet 104a of the second fluid conduit 104 to discharge the flow of the first fluid.

[0044] exist Figure 6 , Figure 11 and Figure 12 In this configuration, the filter base 294 can be fixedly connected to the intermediate housing member 36 (e.g., integrally and integrally formed with the intermediate housing member 36). A third fluid conduit 108 fluidly connects the outlet of the pump 290 to the inlet of the filter base 294, while a fourth fluid conduit 110 fluidly connects the outlet 294a of the filter base 294 to the inlet of the second channel 322 in the heat exchanger 292. The filter base 294 can define a filter chamber 330 configured to receive a filter 296 therein. It will be understood that fluid delivered to the inlet of the filter base 294 via the third fluid conduit 108 will flow through the filter 296, and the filtered fluid will be discharged from the filter base 294 into the fourth fluid conduit 110. In the provided example, the filter 296 is a cartridge filter removable from the generally cylindrical filter chamber 330 in the filter base 294. A filter base plug 332 may be received in a filter cavity 330 and may cooperate with a filter base 294 to isolate the flow of fluid into and out of the filter 296. A spring 334 may optionally be disposed between the housing assembly 12 and the filter base plug 332 to abut the filter base plug 332 against the filter 296. Optionally, the housing assembly 12 may include a filter access cover 338 removably coupled to a first end cap 32. In the example shown, the filter access cover 338 is screwed into a passage hole 340 formed through a wall 342 in the first end cap 32. If desired, a sealing member 344 may be used to form a seal between the filter access cover 338 and the wall 342. The filter access cover 338 is configured to be coaxial with the filter 296 and is sized such that when the filter access cover 338 is removed from the first end cap 32, the filter 296 can be removed through the passage hole 340 in the wall 342.

[0045] refer to Figure 4 , Figure 9 and Figure 10 The rotor heat exchanger 298 is disposed in the rotor 134 and may have a central coolant passage 350 and one or more return passages 352 disposed around the central coolant passage 350. An exemplary rotor heat exchanger 298 is disclosed in more detail in U.S. Application No. 17 / 501,189, filed October 14, 2021, which is jointly assigned and co-pending, and in U.S. Provisional Patent Application No. 63 / 271,937, filed October 26, 2021, the disclosures of which are incorporated herein by reference as if fully set forth herein.

[0046] refer to Figure 3 , Figure 7 and Figures 11 to 13 Pump 290 operates during operation of the electrically driven unit 10 to draw oil-based fluid from the fluid tank S in the second chamber 82. It will be understood that a transfer port 114 formed through the intermediate housing member 36 allows fluid communication between the first chamber 62 and the second chamber 82. The oil-based fluid drawn from the tank flows through the inlet screen 310 and the suction conduit 308 (in the intermediate housing member 36) before entering pump 290. The pressurized fluid leaving pump 290 is delivered via a third fluid conduit 108 to the inlet of filter base 294, through filter 296, and then through the outlet 294a of filter base 294 to the fourth fluid conduit 110. The fourth fluid conduit 110 delivers the pressurized fluid to the second channel 322 in the heat exchanger 292.

[0047] Cooling fluid circulates through a first conduit 100 (in the intermediate housing member 36), a first channel in the heat exchanger 292, and then through a second conduit 104 (in the intermediate housing member 36), while oil-based fluid circulates through a second channel 322 in the heat exchanger 292 to cool the oil-based fluid as it passes through the heat exchanger 292. The oil-based fluid discharged from the second channel 322 is used to cool the inverter 160.

[0048] refer to Figure 4 , Figure 8 and Figure 14The power semiconductor 180 in inverter 160 can generate a significant amount of heat during operation of the electric drive unit 10. Therefore, an oil-based fluid is passed through coolant channel 176 to allow heat to be dissipated from the power semiconductor 180 (via heat sink 182) to the oil-based fluid. A second channel 322 is shown as discharging the oil-based fluid directly into inverter 160; however, it will be understood that a discrete fluid conduit (not shown) can be used to connect the outlet of the second channel 332, formed by heat exchanger 292, to coolant channel 176. If desired, coolant channel 176 can optionally be configured to pass around the axial ends of winding 146 of stator 132 to provide additional cooling to winding 146.

[0049] refer to Figure 4 , Figure 7 , Figure 13 and Figure 15 At least a portion of the oil-based fluid flowing through coolant passage 176 may optionally be transferred to stator coolant channel 148 to cool stator 132. In the provided example, the oil-based fluid flowing through coolant passage 176 is directed to stator coolant channel 148 such that the oil-based fluid passes longitudinally through stator 132 toward intermediate housing member 36. The oil-based fluid is discharged from the opposite axial end of stator 132 (i.e., the axial end of stator 132 near intermediate housing member 36) and may be collected in an annular chamber disposed around the axial end of winding 146 at the opposite axial end of stator 132. The fluid in the annular chamber is discharged through orifice 400 extending through intermediate housing member 36 and may be directed to rotor coolant conduit 402. Rotor coolant conduit 402 may be used to direct the oil-based fluid to central coolant passage 350 in rotor heat exchanger 298. The oil-based fluid travels longitudinally through the rotor 134 to the opposite axial end of the rotor heat exchanger 298 and is guided radially outward into the return passage 352, allowing the oil-based fluid to travel longitudinally through the rotor heat exchanger 298 a second time. The oil-based fluid discharged from the rotor heat exchanger 298 can pass through the housing assembly 12 to lubricate and / or cool various components of the electric drive unit 10, such as the transmission 16 and the differential assembly 18. Figure 3 ).

[0050] refer to Figure 16 and Figure 17The first end cap 32 may optionally define a power connection port 420 and a passage port 422. More specifically, the power connection port 420 and the passage port 422 may be formed through the first peripheral wall member 52 to provide passage to the first cavity 62. The power connection port 420 may provide passage for a pair of cable leads 430 (which may be electrically connected to a power source such as a battery (not shown)) to be inserted along the insertion axis 432 into the housing assembly 12 to engage a pair of motor power terminals 434 disposed on a motor assembly 14 in the first cavity 62. The passage port 422 may provide passage to the motor power terminals 434 at a location spaced apart from the power connection port 420. In the provided example, the passage port 422 provides passage for coupling the cable leads 430 to the motor power terminals 434 using threaded fasteners (not shown). Cable lead 430 can be coupled to connector housing 450, which can be secured to first end cap 32 in any desired manner (such as receiving multiple threaded fasteners through connector housing 450 and screwed into fastener holes in first end cap 32). Passage cover 452 can be secured to first end cap 32 using multiple threaded fasteners to cover passage port 422.

[0051] The preceding description of the embodiments has been provided for illustrative and descriptive purposes. It is not intended to be exhaustive or limiting of this disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but are interchangeable where applicable and can be used in selected embodiments, even if not specifically shown or described. They can also be varied in many ways. Such variations should not be considered as departing from this disclosure, and all such modifications are intended to be included within the scope of this disclosure.

Claims

1. An electric drive unit, comprising: A housing assembly defining an output axis, the housing assembly having a first end cap, a second end cap, an intermediate housing member, a first shaft tube, and a second shaft tube, the first end cap having a first peripheral wall member and a first shaft tube mounting member, the first peripheral wall member defining a first cavity disposed around and extending longitudinally along the output axis, the first shaft tube mounting member defining a first shaft tube bore, the second end cap having a second peripheral wall member and a second shaft tube mounting member, the second peripheral wall member defining a second cavity disposed around and extending longitudinally along the output axis, the second shaft tube mounting member defining a second shaft tube bore, the intermediate housing member being disposed between the first end cap and the second end cap and fixedly connected to the first end cap and the second end cap, the first shaft tube being received in the first shaft tube bore and fixedly connected to the first shaft tube mounting member, the second shaft tube being received in the second shaft tube bore and fixedly connected to the second shaft tube mounting member; An electric motor assembly having a motor housing, a stator, a rotor, and a motor output shaft, the motor housing being fixedly connected to an intermediate housing member and extending into a first cavity, the motor housing being spaced apart from a first peripheral wall member and a first shaft tube mount member, the motor housing defining a motor cavity, the stator being disposed in the motor cavity, the rotor being disposed in the stator to rotate relative to the stator about a motor axis, the motor output shaft being connected to the rotor to rotate with the rotor, and the motor output shaft extending through the intermediate housing member and extending into a second cavity; A transmission is disposed in the second chamber. The transmission has a transmission input component and a transmission output component. The transmission input component is connected to the motor output shaft to rotate with the motor output shaft, and the transmission output component is rotatable about the output axis. A differential assembly is disposed in the second cavity, the differential assembly having a differential input member and a pair of differential output members, the differential input member being coupled to the transmission output member to rotate with the transmission output member; A first output shaft component is received in the first shaft tube and rotatably connected to the first of the pair of differential output components; The second output shaft component is received in the second shaft tube and rotatably connected to the other of the pair of differential output components; as well as The lubrication and cooling system includes a heat exchanger installed at a location within the first cavity to the intermediate housing member. The motor axis is different from the output axis.

2. The electric drive unit according to claim 1, wherein the intermediate housing member is integrally and integrally formed with at least a portion of the motor housing.

3. The electric drive unit of claim 1, wherein the intermediate housing member has a first fluid conduit and a second fluid conduit, the first fluid conduit defining a coolant inlet and fluidly connected to the inlet of a first fluid channel formed by the heat exchanger, and the second fluid conduit defining a coolant outlet and fluidly connected to the outlet of the first fluid channel.

4. The electric drive unit of claim 3, wherein the lubrication and cooling system has a filter base, and wherein the intermediate housing member defines a third fluid conduit that transmits fluid between the filter base and the inlet of a second fluid channel formed by the heat exchanger, wherein the second fluid channel is not in fluid communication with the first fluid channel.

5. The electric drive unit according to claim 4, wherein the filter base is integrally and integrally formed with the intermediate housing member.

6. The electric drive unit of claim 4, wherein the filter base defines a filter cavity, wherein a filter cartridge is received in the filter cavity, and wherein a filter cover is received in a passage hole formed in the first end cap, the filter cover engaging with the first end cap, the passage hole being coaxially disposed with the filter cartridge, wherein the filter cartridge is removable through the passage hole when the filter cover is removed from the first end cap.

7. The electric drive unit of claim 6, wherein the motor assembly further includes a motor controller having an inverter having a plurality of heat dissipation power semiconductors having one or more heat sinks disposed in a coolant channel, and wherein a fluid conduit connects the outlet of the second fluid channel formed by the heat exchanger to the coolant channel.

8. The electric drive unit of claim 7, wherein the stator has a stator body and a plurality of windings, wherein the stator body defines a plurality of stator coolant channels fluidly connected to the coolant channels, and wherein at least a portion of the fluid discharged from the coolant channels is transferred to the stator coolant channels around the axial ends of the windings.

9. The electric drive unit of claim 8, wherein the lubrication and cooling system includes a rotor heat exchanger having a central coolant passage and one or more return passages disposed around the central coolant passage, and wherein a rotor coolant conduit fluidly connects the fluid conduit to the central coolant passage.

10. The electric drive unit of claim 1, wherein the transmission includes a pair of compound gears, each compound gear having a first intermediate gear and a second intermediate gear, the first intermediate gear engaging meshingly with the transmission input gear, the second intermediate gear being coupled to the first intermediate gear to rotate with the first intermediate gear, and the second intermediate gear engaging meshingly with the transmission output gear.

11. The electric drive unit of claim 10, wherein each of the compound gears includes a shaft, wherein a first end of each shaft is supported by a first bearing mounted in a first bearing bore formed in the intermediate housing member, and wherein a second end of each shaft is supported by a second bearing mounted in a second bearing bore formed in the second end cover.

12. The electric drive unit of claim 11, wherein the housing assembly further comprises a pair of bearing caps, each bearing cap being fixedly coupled to the second end cap to close the end of a corresponding second bearing bore.

13. The electric drive unit of claim 1, wherein the first end cap defines a power connection port and a passage panel, the power connection port providing passage along a cable insertion axis to a pair of motor power terminals on the motor assembly, and the passage panel providing passage to the motor power terminals at a location spaced apart from the power connection port.

14. The electric drive unit of claim 1, wherein a plurality of transmission ports are formed through the intermediate housing member, the transmission ports allowing fluid communication between the first cavity and the second cavity.

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