Multi-speed electric driving device

Abstract

The utility model relates to a multi-speed electric driving device. In one example, an electric drive includes first and second motors disposed parallel to each other that are rotationally coupled to a first input gear fixedly coupled to a first driveshaft and a first clutch disposed coaxially with a second clutch. The electric drive also includes a second driveshaft having an output gear rotationally coupled thereto and including first and second mechanical interfaces configured to rotationally couple to the first drive axle and the second drive axle, where the output gear meshes with a gear directly rotationally coupled to a carrier in the planetary gear set.

Description

Technical Field

[0001] The present disclosure relates to an electric drive device having a plurality of electric motors and a method for operating the electric drive device. Background Art

[0002] Electric vehicles use electric drive units to generate power, offering an attractive alternative in terms of hydrocarbon emissions compared to vehicles that rely solely on internal combustion engine propulsion. Some electric drive units use multi-speed transmissions to increase the available gear ratios of the unit. In addition, some electric drive units use dual electric motors to increase the power output and adaptability of the drive unit.

[0003] US Patent No. 10,144,309B2 obtained by Leng et al. discloses a dual-motor drive device for a pure electric vehicle. The dual-motor drive device includes two coaxially arranged motors and a synchronizer. In addition, in Leng's drive device, the shaft as the output of the differential includes three gears.

[0004] The inventors have recognized that Leng's dual motor drive, as well as other previous electric drive systems, have some disadvantages. For example, due to packaging constraints of the surrounding vehicle systems, Leng's drive may not be compatible with certain vehicles that require a multi-drive axle interface with a relatively short flange spacing, such as an all-wheel drive loader. In addition, due to the layout of the synchronizers and associated gear reduction devices on the downstream shaft, the width of the Leng drive may not meet the packaging requirements of certain vehicles. Other dual motor electric drive systems also have difficulty meeting the packaging requirements of certain vehicles, especially in terms of drop and width. Utility Model Content

[0005] In the face of the above problems, the utility model has developed a multi-speed electric drive device, which at least partially overcomes at least some of the above problems. In one example, the electric drive device includes a first motor and a second motor, which are arranged in parallel and rotationally coupled to a first input gear, and the first input gear is fixedly coupled to a first transmission shaft. The electric drive device also includes a first clutch arranged coaxially with a second clutch. In addition, in such an example, the first clutch selectively couples the carrier of the planetary gear set to the first transmission shaft, and the second clutch selectively brakes the ring gear of the planetary gear set. The electric drive device also includes a second transmission shaft with an output gear rotationally coupled thereto. The second transmission shaft includes first and second mechanical interfaces, which are configured to be rotationally coupled to the first drive axle assembly and the second drive axle assembly. In addition, in the drive device, the output gear meshes with a gear that is directly rotationally coupled to the carrier. In this way, the electric drive device can achieve ideal energy and space efficiency (especially in terms of the width and height of the drive device) and a shiftable gear ratio range. In addition, the electric drive device can also drive multiple axle assemblies. Therefore, the attractiveness and applicability of the drive device to customers are expanded.

[0006] Additionally, in one example, the output gear can be positioned axially between the first input gear and the first and second clutches. Positioning the output gear in this manner allows the output gear and associated components to be relatively small in width, thereby allowing the drive unit to be mounted on a vehicle platform with spacing restrictions, such as a loader, in one use case.

[0007] Furthermore, in one example, the electric drive device may further include a third motor that is rotatably connected to the second input gear that is fixedly connected to the first transmission shaft. In this example, the first input gear and the second input gear may be located at opposite ends of the first transmission shaft. Configuring the third motor in the electric drive device allows the electric drive device to provide sufficient traction when stalled to load the bucket of the loader and achieve target top speed and ramp speed, etc. The three-motor layout allows for efficient selection of motors even when there are relatively high requirements for the total power of the transmission. If necessary, this motor structure allows for a relatively low-cost motor solution.

[0008] In another example, the electric drive device may further include a scavenging pump, the suction port of which is located at the vertical low point of the housing. In this way, the splash loss in the transmission device is reduced, thereby further improving the transmission efficiency.

[0009] It should be understood that the above summary is intended to introduce in a simplified form the concepts that are further described in the detailed description. It is not intended to identify key or essential features of the claimed subject matter, the scope of which is uniquely determined by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 A schematic diagram of an electric drive unit in an electric vehicle (EV) is shown.

[0011] Figure 2A and 2B They are shown separately Figure 1 The mechanical power path of the electric drive device in low-speed mode and high-speed mode is shown.

[0012] Figure 2C A table showing clutch position and operating gear mode is shown.

[0013] Figure 3-4 Different perspective views of an exemplary electric drive are shown.

[0014] Figure 5 Shows Figure 3-4 A cross-sectional view of the electric drive shown.

[0015] Figure 6 The method of operation of the electric drive unit is shown. DETAILED DESCRIPTION

[0016] An electric drive unit that achieves an ideal balance between space efficiency, descent, output width, and gear selection is described herein. To achieve the balance between these characteristics, the electric drive unit includes at least two electric motors arranged in parallel with each other and connected to an idler shaft. In detail, a ratio can be established between the electric motor and the low-speed clutch with an idler shaft in between to reduce the triangular speed in the drive unit clutch, thereby reducing drag losses. The electric drive unit also includes an output gear that meshes with a gear that is directionally coupled to a carrier of a planetary gear set. In this way, the output gear and related components can achieve a target compactness (such as output flange to flange distance) to meet the packaging requirements of various space-constrained vehicle platforms such as loaders and trucks. In the electric drive unit, two clutches are coupled to components in the planetary gear set and are coaxially positioned with each other to change the running gear of the drive unit in a space-saving package. In addition, in one example, the electric drive unit can further include a third electric motor connected to the idler shaft. The use of three electric motors in the drive unit allows the drive unit to provide sufficient traction to load the bucket of the loader when stalled and provide maximum speed and ramp speed targets in one example scenario. In addition, the three-motor structure is also effective on vehicle platforms with relatively high total power requirements.

[0017] Figure 1 is a schematic line diagram of a multi-speed, multi-motor electric drive that achieves the required efficiency, operating costs and range in a compact package. Figure 2A and 2B The mechanical power paths in the low speed mode (eg, first gear mode) and the high speed mode (eg, second gear mode) are shown, which allows the transmission ratio adaptability of the device to be expanded. Figure 2C A mapping of clutch configuration to gear ratios is shown. Figure 3 , Figure 4 and Figure 5 An example of a multi-motor electric drive arrangement is shown having a space-saving output assembly to which multiple drive axle assemblies can be connected. Figure 6 A method for effectively achieving power shifting of an electric drive device is shown.

[0018] Figure 1An electric vehicle (EV) 100 is described, which has a multi-speed electric drive 102 that can generate power for vehicle propulsion. The electric vehicle 100 can be a light, medium, or heavy-duty vehicle. Specifically, in one use case, the vehicle can be a loader-type vehicle with a bucket 104 for shoveling loose materials in an industrial, agricultural, or construction environment. The bucket 104 can be driven by a hydraulic, pneumatic, and / or electromechanical system 106. The electric drive 102 may be particularly useful in a loader-type vehicle because of its relatively long drop and short output flange to flange (discussed in more detail herein), which may be required for a loader vehicle. However, in other examples, the electric vehicle 100 can be other suitable types of commercial vehicles, such as trucks. In other examples, the electric vehicle can also be a passenger vehicle, such as a truck, a sedan, a station wagon, etc. In addition, in one example, the electric vehicle 100 can be a battery electric vehicle (BEV) and in another example, a hybrid electric vehicle (HEV) including an internal combustion engine.

[0019] The multi-speed electric drive 102 includes a transmission system 108, a first motor 110, and a second motor 112. The motor can be a traction motor, such as a traction motor generator. Therefore, the use of dual motors in the electric drive can enable the device to achieve end-use performance goals. As shown, the motors 110 and 112 are arranged parallel to each other. In more detail, in one example, the motors can be installed at similar heights in the transmission housing. Arranging the motors in this manner allows the electric drive to achieve ideal weight distribution and axial separation between machines, thereby achieving efficient packaging in the vehicle. However, in other examples, other motor arrangements can also be used. For example, in other examples, the motors can be arranged coaxially. In addition, the parallel motor structure in the electric drive allows the motors to provide target power to the system.

[0020] In the illustrated example, the multi-speed electric drive 102 also includes another electric motor 114. However, the third electric motor may be omitted in other configurations. For example, the end-use design parameters of the vehicle may require that the longitudinal width of the drive unit be less than that achievable with a three-motor configuration. The use of a third electric motor may improve the performance of the drive. In addition, the use of a third electric motor may reduce the likelihood that the drive will not function.

[0021] The first motor 110 is rotationally coupled (e.g., directly rotationally coupled) to the input gear 116 via a shaft 118 and a gear 120. The input gear 116 meshes with the gear 120. As described herein, the coupling between the gears includes meshing between the gear teeth. The shaft 118 is directly coupled to the motor rotor shaft, and the gear 120 is rotationally coupled to the shaft 118. This coupling of rotating components and other rotational couplings between components can be achieved by machining the gear onto the shaft or otherwise integrally forming the gear onto the shaft, press-fitting the gear onto the shaft, splicing the gear with the shaft, welding the gear to the shaft, combining the gear with the shaft, etc. Similarly, the second motor 112 is rotationally coupled (e.g., directly rotationally coupled) to the input gear 116 via a shaft 122 and a gear 124.

[0022] The input gear 116 is located at one axial end 126 of a drive shaft 128. In the illustrated three-motor configuration, another input gear is located at another axial end 130 of the shaft 128. The axial ends 126 and 130 of the shaft 128 are opposing axial ends.

[0023] The motors 110, 112 can be designed to provide the required tractive effort at stall to load the bucket 104 and provide the required top speed and ramp speed as needed. In one example, the bucket 104 can be hydraulically operated. Therefore, in this example, the hydraulic device controlling the bucket can be pressurized by an electric pump.

[0024] Each of the motors 110, 112, 114 may include components such as a rotor and a stator that generate power during operation through electromagnetic interaction. In addition, in one example, the motor may be a motor generator designed to generate electrical energy during regenerative operation. In addition, in some cases, the motors may have similar designs and sizes. This can improve manufacturing efficiency. However, in other examples, the motors may also have different sizes and / or designs.

[0025] When the machine is designed as an alternating current (AC) machine, the motors 110, 112, 114 can be electrically connected to one or more energy storage devices 132 (e.g., one or more traction batteries, capacitors, fuel cells, combinations thereof, etc.) through inverters 134, 136, 140, respectively. Arrow 137 represents the electrical connection between the inverters 134, 136, 140 and the energy storage device 132. Line 138 represents the electrical connection between the motors 110, 112, 114 and the inverters 134, 136, 140. These inverters and other inverters described herein are intended to convert direct current (DC) to alternating current and vice versa. In one use case, the motors 110, 112 and / or 114 and / or the inverters 134, 136 and / or 140 can be multi-phase devices (e.g., three-phase devices), which can achieve higher efficiency than other types of motors. Therefore, in one example, the motor can be a multi-phase AC motor. However, we also envision the use of motors and inverters with more than three phases.

[0026] The motor 114 is connected to the transmission shaft 128 via a shaft 142 (directly connected to the rotor shaft of the motor), a gear 143 and a gear 144 , and the gear 144 is fixedly connected to the transmission shaft 128 .

[0027] In addition, the transmission system 108 also includes a multi-speed transmission 145 (e.g., a two-speed transmission) having a first clutch 146 and a second clutch 148 arranged coaxially with each other. The coaxial arrangement of the clutches allows the transmission to achieve desired packaging goals, especially when used in conjunction with a planetary gear set 150 (e.g., a simple planetary gear set). Specifically, positioning the clutches coaxially with each other allows the clutches to achieve a desired height within the transmission housing. In addition, in the illustrated example, the clutches 146 and 148 are spaced apart from the drive shaft 152 (e.g., the output shaft), but are positioned parallel. In this way, the multi-speed transmission can achieve a reduction in packaging requirements that meet certain loader-type vehicle requirements. However, in other examples, other layouts of the clutches and output shafts can also be used.

[0028] The multi-speed transmission 145 includes a planetary gear set 150, which is shown as a simple planetary gear set. The use of a simple planetary gear set in conjunction with a parallel motor arrangement allows the upper portion of the multi-speed electric drive device 102 to achieve a desired form factor, thereby enabling integration into a wider range of vehicle platforms, such as loaders and trucks. However, as described above, the electric drive device can also be integrated into many other types of vehicles. However, in other examples, the planetary gear set can be a multi-stage planetary gear set, but this may reduce the compactness of the drive device and increase the complexity of the drive device.

[0029] The planetary gear set 150 includes a ring gear 154, planetary gears 156 rotating on a carrier 158, and a sun gear 160. Both the ring gear 154 and the sun gear 160 mesh with the planetary gears 156.

[0030] The first clutch 146 is configured to rotationally couple the carrier 158 to the drive shaft 128 when engaged, and to decouple the carrier from the drive shaft 128 when disengaged. The second clutch 148 is configured to ground the ring gear 154 when engaged, and to allow the ring gear to rotate when disengaged. The ring gear 154 can be specifically grounded to a stationary component 162 (e.g., a housing) of the multi-speed electric drive device 102.

[0031] The first and second clutches 146 and 148 are both illustrated as friction clutches (e.g., wet friction clutches). The use of friction clutches can reduce power interruption during shift transients compared to dog clutches, synchronizers, etc. However, in other examples, the first and / or range clutches can include dog clutches and / or synchronizers.

[0032] The first clutch 146 comprises a plurality of plates 161, which are fixed in different plate carriers 164 (such as drums and sleeves). One of the plate carriers 164 is fixedly connected to the transmission shaft 128 through an extension 163, and the other plate carrier is fixedly connected to the carrier 158 of the planetary gear set 150.

[0033] The second clutch 148 includes a plurality of plates 165, one of which is connected to the ring gear 154 via a plate carrier 166, which is mounted on a shaft 168, which is fixedly connected to the ring gear. Another set of plates in the second clutch is connected to the fixed member 162 via another plate carrier 170.

[0034] The multi-speed transmission 145 also includes an output gear 172. As described herein, the input and output of the transmission are described with respect to mechanical power flowing through the transmission in a drive mode. However, it will be appreciated that when the electric drive device is operating in a regenerative mode, mechanical power will flow back through the transmission to the electric motor. The output gear 172 meshes with a gear 174, which is rotationally coupled (e.g., directly rotationally coupled) to the bracket 158 ​​via a shaft 176. Directly coupling the output gear 172 to the gear 174 allows the transmission to achieve the desired drop, thereby expanding the applicability of the drive device. In addition, the shaft 128 can pass through the central opening 178 on the gear 174 and the shaft 176. In this way, the compactness of the transmission is further improved.

[0035] The output gear 172 is fixedly connected to the shaft 152 (e.g., the output shaft). The shaft 152 has mechanical interfaces 180, 182 (e.g., output interfaces) mounted thereon or formed thereon. As shown by arrows 187, the mechanical interfaces 180, 182 can be connected to axle assemblies 184 and 186 (e.g., front axle assemblies and rear axle assemblies) respectively through shafts, couplings, chains, combinations thereof, etc. The axle assemblies can include components such as differentials, axle shafts, and drive wheels, respectively. Therefore, the multi-speed electric drive device 102 may be suitable for four-wheel drive vehicles. The mechanical interfaces 180, 182 are specifically illustrated as flanges. However, other suitable types of mechanical interfaces are also considered, such as yokes, splines, joints, combinations thereof, etc.

[0036] In the illustrated example, the multi-speed electric drive 102 also includes a dry sump 183. However, in other examples, the drive may omit the dry sump. The dry sump 183 includes a scavenging pump 185 having an oil suction port 187 at a vertical low point 189 of the housing. The scavenging pump 185 delivers lubricating oil (e.g., engine oil) to lubrication system components. For example, the scavenging pump can deliver lubricating oil to nozzles or other components to facilitate lubrication of gears, bearings, etc. in the transmission.

[0037] like Figure 1 As shown, the electric vehicle 100, and in particular the multi-speed electric drive device 102, further includes a control system 190 with a controller 192. The controller 192 may include a microcomputer, whose components include a processor 193 (e.g., a microprocessor unit), input / output ports, and an electronic storage medium 194 (e.g., a read-only memory chip, a random access memory, a surviving memory, a data bus, etc.) for executable programs and calibration values. The storage medium is programmable with computer-readable data representing instructions executable by the processor for performing the methods and control techniques described herein and other variants that are anticipated but not specifically listed.

[0038] The controller 192 may receive various signals from sensors 195 that are coupled to various areas of the electric vehicle 100, the multi-speed electric drive device 102, and the multi-speed transmission 145. For example, the sensors 195 may include a pedal position sensor for detecting the depression of an operator's actuation pedal, such as an accelerator pedal and / or a brake pedal; a speed sensor on the output shaft of the transmission; a state of charge (SOC) sensor of an energy storage device; a clutch position sensor, etc. The motor speed may be determined by the power sent to the motor by the inverter. The input device 197 (e.g., an accelerator pedal, a brake pedal, a drive mode selector, a combination thereof, etc.) may further provide input signals indicative of the operator's vehicle control intent.

[0039] Upon receiving Figure 1After receiving signals from various sensors 195, the controller 192 processes the received signals and uses various actuators 196 of vehicle components to adjust the components based on the received signals and the instructions stored in the memory of the controller 192. For example, the controller 192 can receive an accelerator pedal signal indicating that the operator requires an increase in vehicle acceleration. In response, the controller 192 can instruct the inverters 134, 136 and / or 140 to operate to adjust the motor power output and increase the power delivered to the multi-speed transmission 145 from the motors 110, 112 and / or 114, respectively. Under certain operating conditions, the controller 192 can be designed to send commands to the clutches 146, 148 to engage and disengage the clutches. For example, a control command can be sent to the clutch 146, and the actuator in the clutch can adjust the clutch according to the command to engage or disengage the clutch after receiving the command. For example, other controllable components in the vehicle can play a role in sensor signals, control commands and actuator adjustments in a similar manner.

[0040] Figure 1 as well as Figure 2A , 2B , 3, 4 and 5 provide an axis system for reference. In one example, the z-axis can be a vertical axis (e.g., parallel to the gravity axis), the x-axis can be a lateral axis (e.g., a horizontal axis), and / or the y-axis can be a longitudinal axis. However, in other examples, these axes may have other directions.

[0041] Figure 2A and 2B Mechanical power paths 200 and 202 through the multi-speed electric drive device 102 in a low speed mode (such as a first gear mode) and a high speed mode (such as a second gear mode) are shown, respectively. It will be appreciated that the control system 190 can be used to switch between these modes. For the sake of brevity, redundant descriptions of the control system and electric drive device components are omitted, although these components are numbered similarly. The gear ratio of the transmission in the low speed mode is higher than the gear ratio in the high speed mode. Therefore, the low speed mode can be used when the vehicle is running at a low speed, and the high speed mode can be used when the vehicle is running at a high speed. It will be appreciated that these mechanical power paths may correspond to forward and reverse drive modes. In addition, in the forward and reverse drive modes, the motor can produce rotational outputs in opposite directions. In other words, in the forward drive mode, the first motor can rotate the shaft 118 in a first direction, and in the reverse drive mode, it can rotate the shaft 118 in the opposite direction. Therefore, Figure 2A and 2B The mechanical power path shown in generally corresponds to drive mode operation. Figure 2A and 2BIn the embodiment, the first motor 110, the second motor 112 and the third motor 114 operate to generate a mechanical power output. Therefore, the inverters 134, 136 and 140 can operate to transfer electrical energy from the energy storage device 132 to the corresponding motors. However, in other examples, only some of the motors may operate. For example, in some examples, the third motor may not operate or may be omitted from the electric drive device.

[0042] like Figure 2A As shown, when the multi-stage electric drive device 102 is operated in the low speed mode, the first clutch 146 is disengaged and the second clutch 148 is engaged. The mechanical power path 200 is developed as follows: mechanical power is transmitted from the first and second motors 112, 114 to the gear 116, from the third motor 114 to the gear 144; from the gears 116 and 144 to the sun gear 160; from the sun gear 160 to the carrier 158 through the planetary gears 156; from the carrier 158 to the gear 174; from the gear 174 to the gear 172; from the gear 172 to the shaft 152; and from the shaft 152 to the mechanical interfaces 180 and 182. Power is transmitted from the mechanical interface to the downstream components in the axle assemblies 184 and 186, and finally to the drive wheels.

[0043] like Figure 2B As shown, when the multi-speed electric drive device 102 is operated in the higher speed mode, the first clutch 146 is in an engaged state and the second clutch 148 is in a disengaged state. The mechanical power path 202 is developed as follows: mechanical power moves from the first and second motors 112, 114 to gear 116, from the third motor 114 to gear 144; from gears 116 and 144 to extension 163; from extension 163 to the first clutch 146; from the first clutch 146 to the carrier 158; from the carrier 158 to gear 174; from gear 174 to gear 172; from gear 172 to shaft 152; and from shaft 152 to mechanical interfaces 180 and 182. Power is transmitted from the mechanical interface to downstream components in the axle assemblies 184 and 186, and finally to the drive wheels.

[0044] Figure 2C A table 250 is shown, which illustrates the configuration of the first clutch 146 and the second clutch 148 in the low speed mode and the high speed mode. As described above, in the low speed mode, the clutch 148 is in the engaged state and the clutch 146 is in the disengaged state, whereas in the second gear mode, the clutch 148 is in the disengaged state and the clutch 146 is in the engaged state. The gear ratio of the low speed mode is higher than that of the high speed mode. Therefore, the low speed mode (such as the first gear mode) can be used when the vehicle is started and traveling at a low speed, while the high speed mode (such as the second gear mode) can be used when the vehicle is traveling at a high speed.

[0045] Figure 3-5 An example of a multi-speed electric drive 300 is shown. Figure 3 The multi-speed electric drive device 300 shown in the figure includes a first motor 302 (e.g., a traction motor, such as a traction motor generator) and a second motor 304 (e.g., a traction motor, such as a traction motor generator), and a housing 306, the housing 306 including a multi-speed transmission 307, such as Figure 5 Although the electric drive is shown with two traction motors, in other designs, the electric drive may also use a third traction motor.

[0046] like Figure 3 As shown, the rotation axes 308, 310 of the first motor 302 and the second motor 304 are parallel to each other. In more detail, the heights of the motors 302 and 304 relative to the vertical axis are substantially the same. Positioning the motors in this manner allows the drive device to be installed on a vehicle platform with limited space.

[0047] The housing 306 can be conceptually divided into different parts. Specifically, the housing includes an upper part 312, a motor interface 313 on one side 314, and a transmission housing 316 on the other side 318. In this way, the drive device can achieve a higher mass balance.

[0048] The mechanical interface 320 shown in the figure is located in the lower portion 322 of the housing 306, which is configured to be rotatably connected to the drive shaft assembly. The width 324 of the lower portion 322 of the housing is less than the width 326 of the upper portion 312. In one use case, designing a transmission with this width difference can more effectively integrate the transmission into a space-constrained vehicle platform, such as a loader-type vehicle. Figure 3 A base 328 of the transmission 307 is further shown.

[0049] Figure 4 Another view of a multi-speed electric drive 300 is shown, including electric motors 302 and 304 and housing 306 . Figure 4 Another mechanical interface 400 at the output of the transmission is shown. The mechanical interface 400 is used for rotational connection to another drive axle assembly. The figure again shows the upper housing portion 312 and the lower housing portion 322 with the transmission housing 316. In the illustrated example, the transmission housing 316 is cylindrical. However, in other examples, the transmission housing can also have other contours. For example, in other examples, the transmission housing can include multiple planes. Figure 4 A cutting surface 5-5' is shown in FIG. Figure 5 Cross-sectional view described in .

[0050] Figure 5A cross-sectional view of a multi-speed electric drive 300 with a transmission 307 is shown. It will be appreciated that Figure 5 The transmission 307 and Figure 1 The transmission 145 shown has a similar structure in terms of the number of clutches, planetary gear set layout, shaft locations, etc.

[0051] Figure 5 A drive shaft 500 (e.g., an idler shaft) and an output shaft 502 are specifically described. An output gear 504 is fixedly coupled to or otherwise integrally formed with the output shaft 502. Bearings 506 are located on opposite sides of the output gear 504, and the mechanical interfaces 320 and 400 are located on opposite axial ends 508 of the output shaft 502 in the illustrated example. In one example, the output assembly 510 may include only the output gear 504, the bearings 506, the output shaft 502, and the mechanical interfaces 320, 400 to reduce the width of the lower portion 322 of the housing 306. In this way, the transmission can be installed in an environment with limited space. The upper portion 312 of the housing 306, particularly the housing 316, contains the multi-speed transmission 307.

[0052] Figure 5 A clutch 512 (eg, a friction clutch) is further shown in the multi-speed transmission 307 . The clutch 512 is configured to selectively couple an extension 514 fixedly connected to the shaft 500 with a carrier 516 in a planetary gear set 518 .

[0053] Another clutch 520 (eg, a friction clutch) such as Figure 5 As shown. The clutch 520 is configured to selectively brake the ring gear 522 in the planetary gear set 518 through the ring gear extension 523. The ring gear extension 523 can at least partially surround the clutch 512 to improve the compactness of the transmission. However, other clutch extension profiles can also be used in other examples.

[0054] As shown, clutch 512 and clutch 520 are arranged coaxially. This coaxial clutch arrangement can improve the compactness of the transmission. Therefore, in a specific use case, the electric transmission can be used in a space-constrained vehicle platform, such as a loader type vehicle. Planetary gear set 518 also includes a sun gear 521 and planetary gears 524 rotating on carrier 516.

[0055] The output gear 504 meshes with a gear 526, which is rotationally coupled to the carrier 516 via an extension 527. The multi-speed transmission 307 also includes an input gear 528, which meshes with a gear 530, which is connected to the motor 304 via a shaft 532. Figure 4As shown, the motor 304 can be connected to the input gear 528 in a similar manner. In the illustrated example, the gear 526 is axially located between the input gear 528 and the clutches 512 and 520. In this way, the structure of the electric transmission is more compact. However, in other transmission structures, the gears can also be set at other suitable positions.

[0056] like Figure 5 As shown, bearings 534 are connected to opposite ends of shaft 500. Additionally, bearings 536 are connected to ring gear extension 523 and shaft 500. Bearing 538 is connected to clutch extension 540. However, other bearing arrangements in the transmission are also contemplated.

[0057] Figure 5 Further shown is the transmission drop 328 and the length 542 of the output shaft 502, which may represent the output flange-to-flange distance of the transmission. The electric multi-speed transmission 307 implements a relatively long drop and a short output flange-to-flange distance, which may be particularly desirable in a loader type vehicle. However, as previously mentioned, the electric transmission may be used in a variety of vehicle types.

[0058] The multi-speed electric drive 300 may also include a scavenger pump 550 having a suction port 552 located at a low point of the oil sump 554 in the housing 306. This may reduce transmission efficiency by reducing churning losses. However, in other examples, the transmission may include a wet sump to provide splash lubrication for the gears, bearings, and / or clutches in the transmission.

[0059] Figure 5 500 and 502, and the rotational axis 310 of the motor 304 are provided for reference. In the illustrated example, these rotational axes are parallel to each other. However, in other examples, at least some of the axes may have other directions.

[0060] Figure 6 A method 600 for operating an electric drive device is shown. In one example, the method 600 may be performed by Figure 1-5 The method 600 may be performed by any electric drive unit or combination of electric drive units described above. In other examples, the method 600 may be performed by other suitable electric drive devices. In addition, as previously described, the method 600 may be performed by a controller including a memory for storing method step instructions executable by a processor.

[0061] Figure 6The illustrated method 600 includes determining operating conditions at 602. The operating conditions may include input device position (e.g., shift lever position), clutch configuration, accelerator pedal position, transmission input / output speeds, motor speed, vehicle speed, vehicle load, ambient temperature, etc. The operating conditions may be determined via sensor input, modeling, lookup tables, and / or other suitable techniques.

[0062] Next, at 604, the method includes determining whether the electric multi-speed transmission should perform a power shift. In one example, this determination can be made based on the vehicle speed exceeding a threshold. In other examples, the operator's interaction with the gear selector can initiate a power shift operation.

[0063] If it is determined that a power shift should not be performed (NO at 604), the method will proceed to 606, which includes maintaining the current operating strategy of the transmission. For example, the transmission can remain in a lower gear or a higher gear.

[0064] Conversely, if it is determined that a power shift should be performed ("yes" at 604), the method proceeds to 608, which includes engaging the first clutch while disengaging the second clutch while maintaining power transmission from the motor to the transmission to transition from a low gear to a high gear. In this way, if necessary, the shift can be performed with little or no power interruption. It will be appreciated that the power shift can be transitioned from a high speed mode to a low speed mode in a similar manner.

[0065] A technical effect of the electric drive device operating method described herein is to provide an electric drive device having multiple selectable gears that achieves targeted compactness and gear ratios, thereby enabling the drive device to be packaged in a space-constrained vehicle platform.

[0066] Figure 1-2B and Figure 3-5An example of component configuration in which each component is relatively positioned is shown. If the elements shown in the figure are in direct contact or directly coupled to each other, then at least in one example, these elements may be referred to as directly contacting or directly coupled to each other, respectively. Similarly, at least in one example, the elements shown as being adjacent or adjacent to each other may be adjacent or adjacent to each other, respectively. For example, elements that are in face-to-face contact with each other may be referred to as face-to-face contact elements. Another example is that, at least in one example, the elements are placed separately from each other, with only space in the middle and no other elements, which may be referred to as being placed separately from each other. For another example, relative to each other, the elements displayed above / below each other, relative to both sides of each other, or relative to the left / right side of each other may be referred to as such elements. In addition, as shown in the figure, in at least one example, the topmost element or element point may be referred to as the "top" of the element, and the bottommost element or element point may be referred to as the "bottom" of the element. As used herein, up / down, up / down, up / down may be relative to the vertical axis in the figure, for describing the positioning of each element in the figure relative to each other. Therefore, in one example, the element displayed above other elements is vertically positioned above other elements. For another example, the shapes of the elements depicted in the figures may be referred to as having these shapes (such as circular, linear, planar, curved, rounded, chamfered, beveled, or the like). In addition, in one example, elements that are coaxial with each other may be referred to as coaxial elements. In addition, at least in one example, elements that are shown to intersect with each other may be referred to as intersecting elements or intersecting with each other. In addition, in one example, elements that are displayed within another element or displayed outside another element may also be referred to as intersecting elements. In other examples, elements that are offset from each other may also be referred to as such. Even further, elements that are coaxial or parallel to each other may also be referred to as such elements. Further still, the axis around which the element rotates may be referred to as the axis of rotation.

[0067] The utility model will be further described below. In one aspect, the utility model provides a multi-speed electric drive device, the device comprising a first motor and a second motor arranged in parallel with each other, which are rotationally coupled to a first input gear fixedly coupled to a first transmission shaft; a first clutch arranged coaxially with a second clutch; wherein the first clutch selectively rotationally couples a carrier of a planetary gear set to the first transmission shaft; wherein the second clutch selectively brakes a ring gear of the planetary gear set; and a second transmission shaft, on which an output gear is rotationally coupled, and comprises first and second mechanical interfaces, which are configured to be rotationally coupled to a first drive axle assembly and a second drive axle assembly; and wherein the output gear meshes with a gear directly rotationally coupled to the carrier.

[0068] In another aspect, a method for operating an electric drive unit is provided, the method comprising: power shifting between a low speed mode and a high speed mode by engaging a first friction clutch and disengaging a second friction clutch or vice versa; wherein the electric drive unit comprises a first traction motor and a second traction motor arranged in parallel with each other and rotationally coupled to a first input gear fixedly coupled to a first transmission shaft; a first friction clutch arranged coaxially with the second friction clutch; and a second transmission shaft, on which an output gear is rotationally coupled and comprises first and second mechanical interfaces configured to be rotationally coupled to a first drive axle assembly and a second drive axle assembly; wherein the output gear meshes with a gear directly rotationally coupled to a carrier. Further in one example, wherein the electric drive unit may further comprise a third traction motor rotationally coupled to a second input gear fixedly coupled to the first transmission shaft, and wherein the method may further comprise operating the first, second and third traction motors simultaneously during power conversion between the low speed mode and the high speed mode.

[0069] In another aspect, a two-speed electric drive device is provided, which includes a first traction motor and a second traction motor arranged in parallel with each other, each motor being rotationally coupled to an input gear fixedly coupled to a first transmission shaft; and an electric transmission device including a first friction clutch arranged coaxially with a second friction clutch; wherein the first friction clutch selectively rotationally couples a carrier of a planetary gear set to the first transmission shaft; wherein the second friction clutch selectively brakes a ring gear of the planetary gear set; and a second transmission shaft, on which an output gear is rotationally coupled, and includes a first and a second mechanical interface, which is configured to be rotationally coupled to a first drive axle assembly and a second drive axle assembly, respectively; wherein the output gear meshes with a gear directly rotationally coupled to the carrier.

[0070] In any or any combination of the above aspects, the output gear may be disposed axially between the first input gear and the first and second clutches.

[0071] In the above aspects or combinations of the aspects, the electric drive device may further include a third motor, the third motor is rotationally coupled to the second input gear, and the second input gear is fixedly coupled to the first transmission shaft.

[0072] In any or any combination of the above aspects, the first input gear and the second input gear may be located at opposite ends of the first transmission shaft.

[0073] In any or any combination of the above aspects, the first and second clutches may be friction clutches.

[0074] In any one or combination of the above aspects, the first and second motors may be disposed on a first longitudinal side of the electric drive device, and the first and second clutches may be disposed on a second longitudinal side of the electric drive device opposite the first longitudinal side.

[0075] In any or any combination of the above aspects, the output shaft assembly may include only the output shaft, the first mechanical interface, the second mechanical interface, the output gear, and two bearings located on opposite sides of the output gear.

[0076] In any or any combination of the above aspects, the first motor and the second motor may have the same vertical height within the housing of the multi-speed electric drive device.

[0077] In any or any combination of the above aspects, the planetary gear set can be a simple planetary gear set.

[0078] In any or any combination of the above aspects, the electric drive device may further include a scavenging pump having a pickup located at a vertically low point of the housing.

[0079] In any or any combination of the above aspects, the first and second electric motors may be multi-phase alternating current (AC) motors.

[0080] In any or any combination of the above aspects, the electric drive device may be included in an all-electric vehicle.

[0081] In any or any combination of the above aspects, the electric drive device may be included in a loader-type vehicle.

[0082] In the above aspects or combinations of the aspects, when the first friction clutch is engaged, the carrier in the planetary gear set can be rotationally coupled to the first transmission shaft; when the second friction clutch is engaged, the ring gear of the planetary gear set can be braked.

[0083] In any one or a combination of the above aspects, the electric drive device may further include a third traction motor, which is rotationally coupled to a second input gear fixedly coupled to the first transmission shaft; wherein the output gear may be axially positioned between the first input gear and the first and second friction clutches; and the first input gear and the second input gear may be positioned at opposite ends of the first transmission shaft.

[0084] In any or any combination of the above aspects, the third traction motor may have a lower vertical height than the first and second traction motors of the same height.

[0085] In any or any combination of the above aspects, the two speed electric drive may be mounted on a loader vehicle including an adjustable front mounted bucket.

[0086] In each or any combination of the above aspects, the first traction motor and the second traction motor may be coupled to the first input gear respectively via a gear which rotates on a shaft which is directly rotationally coupled to the rotor shaft of the corresponding traction motor.

[0087] In any or any combination of the above aspects, the first and second friction clutches may be enclosed in a housing, wherein the housing includes a dry sump.

[0088] In another representation, a multi-motor electric vehicle system is provided, the system including two motors having parallel rotation axes and disposed on one side of a transmission housing, and a two-speed transmission on an opposite side of the transmission housing, wherein the two-speed transmission includes a bracket directly coupled to an output gear rotating on an output shaft, and includes a front drive axle interface and a rear drive axle interface.

[0089] In another formulation, an electric transmission is provided that includes two motor generators arranged at equal heights, a two-speed gear assembly (with first and second wet friction clutches arranged coaxially with each other) and a simple planetary gear set (with a carrier directly coupled to the output gear).

[0090] In any or any combination of the above aspects, the first and second drive axle assemblies are a front drive axle assembly and a rear drive axle assembly.

[0091] Please note that the control and estimation routine examples included herein can be used in various system (e.g., powertrain) configurations. The control methods and routines disclosed herein can be stored as executable instructions in non-transitory memory and can be executed by a control system that includes a controller, various sensors, actuators, and other system hardware combined with an electronic controller. Therefore, the actions, operations, and / or functions described can be graphically represented as codes that will be programmed into the non-transitory memory of a computer-readable storage medium in a vehicle and / or powertrain control system. The various operations, operations, and / or functions illustrated can be performed in the order illustrated, in parallel, or omitted in some cases. Similarly, the processing order is not necessarily required to achieve the features and advantages of the examples described herein, but is only for ease of illustration and description. Depending on the specific strategy used, one or more of the illustrated actions, operations, and / or functions can be repeated. If necessary, one or more of the method steps described herein can be omitted.

[0092] Although various embodiments are described above, it should be understood that these embodiments are examples only and not limitations. It is obvious to those familiar with the relevant technology that the disclosed subject matter can be embodied in other specific forms without departing from the spirit of the subject matter. Therefore, the embodiments described above should be considered in all respects to be illustrative and not restrictive. Therefore, the configurations and routines disclosed herein are exemplary in nature, and these specific examples should not be considered restrictive because there can be many variations. For example, the above-described technology can be applied to power systems that include different types of propulsion sources, including different types of traction motors, internal combustion engines in some cases, transmissions, etc. The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of various systems and configurations, as well as other features, functions and / or attributes disclosed herein. In addition, the following components are also included

[0093] The following claims particularly point out certain combinations and subcombinations regarded as novel and non-obvious. The claims may refer to "an" element or a "first" element or its equivalent. The claims should be understood to include one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and subcombinations of the disclosed features, functions, elements, and / or properties may be claimed by amendment of the present claims or by presentation of new claims in this or a related application. Such claims, whether broader, narrower, equal, or different in scope to the original claims, are also deemed to be included in the subject matter of the present disclosure.

Claims

1. A multi-speed electric drive device, comprising: A first motor and a second motor are arranged in parallel with each other, the first motor and the second motor are rotatably connected to a first input gear, and the first input gear is fixedly connected to a first transmission shaft; a first clutch arranged coaxially with a second clutch; wherein the first clutch selectively rotationally couples the carrier of the planetary gear set to the first transmission shaft; wherein the second clutch selectively brakes the ring gear of the planetary gear set; and a second transmission shaft having an output gear rotationally coupled thereto, the second transmission shaft including a first mechanical interface and a second mechanical interface rotationally coupled to the first and second drive axle assemblies; and Wherein, the output gear meshes with a gear which is directly rotationally coupled to the bracket.

2. The multi-speed electric drive device according to claim 1, characterized in that: A gear directly rotationally coupled to the carrier is located axially between the first input gear and the first and second clutches.

3. The multi-speed electric drive device according to claim 1, characterized in that: A third motor is also included, the third motor is rotationally connected to the second input gear, and the second input gear is fixedly connected to the first transmission shaft.

4. The multi-speed electric drive device according to claim 3, characterized in that: The first input gear and the second input gear are located at opposite ends of the first transmission shaft.

5. The multi-speed electric drive device according to claim 1, characterized in that: The first and second clutches are friction clutches.

6. The multi-speed electric drive device according to claim 1, characterized in that: The first and second motors are located on a first longitudinal side of the multi-speed electric drive device, and the first and second clutches are located on a second longitudinal side of the multi-speed electric drive device opposite the first longitudinal side.

7. The multi-speed electric drive device according to claim 1, characterized in that: The output shaft assembly only includes the output shaft, the first mechanical interface, the second mechanical interface, the output gear and two bearings located on opposite sides of the output gear.

8. The multi-speed electric drive device according to claim 1, characterized in that: The first electric motor and the second electric motor are at equal vertical heights within the housing of the multi-speed electric drive.

9. The multi-speed electric drive device according to claim 1, characterized in that: The planetary gear set is a simple planetary gear set.

10. The multi-speed electric drive device according to claim 1, characterized in that: A scavenger pump is also included, with its suction port located at the low vertical point of the housing.

11. The multi-speed electric drive device according to claim 1, characterized in that: The first and second electric motors are multi-phase alternating current (AC) motors.

12. The multi-speed electric drive device according to claim 1, characterized in that: A multi-speed electric drive is included in a loader vehicle including an adjustable front bucket; The first and second electric motors are each coupled to the first input gear via a gear that rotates on a shaft that is directly rotationally coupled to the rotor shaft of the respective electric motor; and / or The first and second clutches are enclosed in a housing, wherein the housing includes a dry sump.

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