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CN-121989653-A - Driving unit

CN121989653ACN 121989653 ACN121989653 ACN 121989653ACN-121989653-A

Abstract

The invention provides a driving unit, which suppresses imbalance of left and right masses of the driving unit. The vehicle drive unit may include a first motor, a first speed reducer, a first inverter, a second motor, a second speed reducer, and a second inverter, a locking mechanism that mechanically locks and unlocks the first speed reducer, and a housing that accommodates the members, the housing having a first portion disposed on one of the pair of left and right wheels and a second portion disposed on the other of the pair of left and right wheels when the drive unit is mounted on the vehicle, the first motor, the first speed reducer, the first inverter, and the locking mechanism being disposed in the first portion of the housing, the second motor, the second speed reducer, and the second inverter being disposed in the second portion of the housing, and a motor center plane that is equally divided between the first motor and the second motor being offset toward the second portion of the housing with respect to an inverter center plane that is equally divided between the first inverter and the second inverter.

Inventors

  • Yuragi Yusuke
  • HIROSHI ODA
  • ITO EIJI
  • NAITO NAOTO

Assignees

  • 丰田自动车株式会社

Dates

Publication Date
20260508
Application Date
20251028
Priority Date
20241106

Claims (10)

  1. 1. A drive unit for a vehicle, which independently drives a pair of left and right wheels, wherein, The drive unit is provided with: A first motor for driving one of the pair of left and right wheels; a first speed reducer that reduces rotation of the first motor; a first inverter electrically connected to the first motor; A second motor for driving the other of the pair of left and right wheels; A second speed reducer for reducing the rotation of the second motor; A second inverter electrically connected to the second motor; a locking mechanism mechanically locking and unlocking the first decelerator, and A housing accommodating the first motor, the first speed reducer, the first inverter, the second motor, the second speed reducer, the second inverter, and the locking mechanism, The housing has a first portion disposed on one side of the pair of left and right wheels and a second portion disposed on the other side of the pair of left and right wheels when the drive unit is mounted on the vehicle, The first motor, the first decelerator, the first inverter, and the locking mechanism are disposed at the first portion of the housing, The second motor, the second speed reducer and the second inverter are disposed at the second portion of the housing, A motor center plane dividing equally between the first motor and the second motor is offset toward the second portion side of the housing with respect to a inverter center plane dividing equally between the first inverter and the second inverter.
  2. 2. The drive unit of claim 1, wherein, The housing has a first oil pan provided at a lower portion of the first portion and a second oil pan provided at a lower portion of the second portion, An oil pan center surface that bisects between the first oil pan and the second oil pan is offset toward the first portion side of the housing with respect to the motor center surface.
  3. 3. The drive unit of claim 1, wherein, The driving unit is connected with a first driving shaft connected with one of the left and right wheels and a second driving shaft connected with the other of the left and right wheels, The center of gravity of the driving unit is located on an inner end center plane which equally divides between the inner end of the first driving shaft and the inner end of the second driving shaft of the first driving shaft.
  4. 4. The drive unit of claim 1, wherein, The drive unit further includes: a first terminal block fixed to the housing; A first conductive path electrically connecting the first inverter and the first motor via the first terminal; A second terminal block fixed to the housing, and A second conductive path electrically connecting the second inverter and the second motor via the second terminal block, The overall length of the first conductive path and the overall length of the second conductive path are different from each other, The section length of the first conductive path from the first motor to the first terminal block and the section length of the second conductive path from the second motor to the second terminal block are equal to each other.
  5. 5. The drive unit according to any one of claims 1 to 4, wherein, The first motor and the second motor are arranged symmetrically with respect to the motor center plane.
  6. 6. The drive unit according to any one of claims 1 to 4, wherein, The first inverter and the second inverter are arranged in bilateral symmetry with respect to the inverter center plane.
  7. 7. The drive unit according to any one of claims 1 to 4, wherein, The housing has: A first motor chamber which is located at the first portion and accommodates the first motor and the first decelerator; A second motor chamber located at the second portion and accommodating the second motor and the second speed reducer, and A motor chamber partition wall located on the motor center plane and at least partially isolating the first motor chamber from the second motor chamber.
  8. 8. The drive unit of claim 7, wherein, The housing further has: a first inverter chamber located in the first portion and accommodating the first inverter; a second transducer chamber located in the second portion and housing the second transducer, and A transducer chamber dividing wall located on the transducer center plane and at least partially isolating the first transducer chamber from the second transducer chamber.
  9. 9. Drive unit according to claim 1 or 2, wherein, The locking mechanism is provided to a rotation shaft that connects the first motor and the first speed reducer.
  10. 10. The drive unit of claim 9, wherein, The locking mechanism has: a locking gear fixed to the rotation shaft, and A lock pawl movable between a lock position engaged with the lock gear and an unlock position disengaged from the lock gear.

Description

Driving unit Technical Field The technology disclosed in the present specification relates to a drive unit for a vehicle. Background Patent document 1 describes a drive unit for a vehicle. The driving unit includes two motors and two decelerator, and independently drives a pair of left and right wheels. Prior art literature Patent literature Patent document 1 Japanese patent laid-open No. 2017-047698 Disclosure of Invention Problems to be solved by the invention In the above-described drive unit, the two motors and the two reducers are arranged bilaterally symmetrically. In this way, in the driving unit that drives the pair of left and right wheels independently, it is preferable that the paired components such as the motor and the speed reducer are arranged in a balanced manner. However, the components of the drive unit also include unpaired components like the lock mechanism. The lock mechanism is also called a parking lock, for example, and is provided to one of the two decelerator, and configured to lock and unlock the one decelerator. Due to the presence of the locking mechanism, an imbalance of the left and right masses may occur in the drive unit. The present specification provides a technique capable of suppressing such unbalance. Means for solving the problems The technology disclosed in the present specification is embodied as a driving unit for a vehicle that drives a pair of left and right wheels independently. The drive unit may include a first motor that drives one of the pair of left and right wheels, a first speed reducer that reduces rotation of the first motor, a first inverter that is electrically connected to the first motor, a second motor that drives the other of the pair of left and right wheels, a second speed reducer that reduces rotation of the second motor, a second inverter that is electrically connected to the second motor, a locking mechanism that mechanically locks and unlocks the first speed reducer, and a case that accommodates the first motor, the first speed reducer, the first inverter, the second motor, the second inverter, and the locking mechanism, wherein the case has a first portion disposed on one side of the pair of left and right wheels and a second portion disposed on the other side of the pair of left and right wheels when the drive unit is mounted on a vehicle, and wherein the first motor, the first speed reducer, the first inverter, the second inverter, and the second portion are disposed between the first motor and the second inverter, and the second housing, and the second portion are offset from each other with respect to the center, and the case. In the above-described driving unit, the first motor, the first speed reducer, the first inverter, and the locking mechanism are disposed in a first portion of the housing (i.e., one side of the pair of right and left wheels), and the second motor, the second speed reducer, and the second inverter are disposed in a second portion of the housing (i.e., the other side of the pair of right and left wheels). That is, the locking mechanism is only present in the first portion of the housing, and no structure corresponding thereto is present in the second portion of the housing. In the driving unit, the first motor and the second motor are disposed such that the center of gravity of the entire first motor and the second motor is offset toward the second portion side with respect to the center plane of the inverter that equally divides the space between the first inverter and the second inverter. Specifically, a motor center surface dividing equally between the first motor and the second motor is offset toward the second portion side of the housing with respect to a inverter center surface dividing equally between the first inverter and the second inverter. Thus, even when the drive unit has a lock mechanism, imbalance in the left and right masses of the drive unit can be suppressed. Drawings Fig. 1 is a block diagram showing a vehicle when viewed from above. Fig. 2 is a schematic diagram showing a driving unit. Fig. 3 shows a circuit diagram of the drive unit. Fig. 4 is a diagram showing a structure of the lock mechanism. Fig. 5 is an enlarged view of the V portion of fig. 2. Detailed Description In the first aspect of the present technology, as described above, the drive unit is a drive unit for a vehicle that independently drives a pair of left and right wheels, respectively. The drive unit may include a first motor that drives one of the pair of left and right wheels, a first speed reducer that reduces rotation of the first motor, a first inverter that is electrically connected to the first motor, a second motor that drives the other of the pair of left and right wheels, a second speed reducer that reduces rotation of the second motor, a second inverter that is electrically connected to the second motor, a locking mechanism that mechanically locks and unlocks the first speed reducer, and a case that accommodates the f