Motor drive unit

Patent metadata

Field	Value
Publication number	US-10358051-B2
Application number	US-201715412946-A
Country	US
Kind code	B2
Filing date	Jan 23, 2017
Priority date	Jan 22, 2016
Publication date	Jul 23, 2019
Grant date	Jul 23, 2019

Abstract

A motor drive unit having an inboard brake in which a lateral weight distribution is balanced is provided. In the motor drive unit, output torque of a drive motor is distributed to a right driveshaft and a left driveshaft via a drive gear a drive gear fitted onto an output shaft thereof. A brake rotor is also fitted onto the output shaft to be rotated integrally therewith. A brake device stops rotation of the drive gear by engaging the brake rotor with a brake stator that is allowed to rotate relatively to the brake rotor but restricted to rotate in a rotational direction of the brake rotor. The brake device is disposed on an opposite side of the drive motor across the drive gear.

First claim

What is claimed is:

1. A motor drive unit, comprising:
a drive motor serving as a prime mover of a vehicle;
a first differential unit having a first input element, a first output element and a first reaction element;
a second differential unit having a second input element, a second output element and a second reaction element;
a connection shaft connecting the first input element and the second input element;
an input gear fitted onto the connection shaft between the first input element and the second input element;
a drive gear fitted onto an output shaft of the drive motor while being meshed with the input gear to transmit torque between the connection shaft and the output shaft;
a torque reversing mechanism that transmits torque of any one of the first reaction element and the second reaction element to the other reaction element while reversing a direction of the torque;
a first driveshaft connected to the first output element and a second driveshaft connected to the second output element to which output torque of the drive motor is distributed; and
a brake device that stops rotation of the drive gear fitted onto the output shaft when a predetermined current is supplied to the brake device, the brake device stopping the rotation by engaging at least one rotary member rotated integrally with the output shaft with at least one brake member that is allowed to rotate relatively to the rotary member but restricted to rotate in a rotational direction of the rotary member,
wherein the brake device is disposed on an opposite side of the drive motor across the drive gear fitted onto the output shaft.

2. The motor drive unit as claimed in claim 1 , wherein
the brake device includes an electromagnetic brake that establishes a magnetic attraction when energized to engage the brake member with the rotary member.

3. The motor drive unit as claimed in claim 1 , wherein
the brake device comprising a parking brake continues to stop the rotation of the drive gear fitted onto the output shaft when the brake device is un-energized.

4. A motor drive unit, comprising:
a drive motor serving as a prime mover of a vehicle;
a first differential unit having a first input element, a first output element and a first reaction element;
a second differential unit having a second input element, a second output element and a second reaction element;
a connection shaft connecting the first input element and the second input element;
an input gear fitted onto the connection shaft between the first input element and the second input element;
a drive gear fitted onto an output shaft of the drive motor while being meshed with the input gear to transmit torque between the connection shaft and the output shaft;
a torque reversing mechanism that transmits torque of any one of the first reaction element and the second reaction element to the other reaction element while reversing a direction of the torque;
a first driveshaft connected to the first output element and a second driveshaft connected to the second output element to which output torque of the drive motor is distributed;
a brake device that stops rotation of the drive gear fitted onto the output shaft by engaging at least one rotary member rotated integrally with the output shaft with at least one brake member that is allowed to rotate relatively to the rotary member but restricted to rotate in a rotational direction of the rotary member, the brake device being disposed on an opposite side of the drive motor across the drive gear fitted onto the output shaft;
a brake motor that generates torque when energized; and
an engagement force generating device that generates a thrust force to bring the brake member into frictional engagement with the rotary member when the torque of the brake motor is applied thereto, and that keeps the frictional engagement between the brake member and the rotary member to stop rotation of the output shaft when current supply to the brake motor is interrupted, wherein
the brake motor and the engagement force generating device are disposed on the opposite side of the drive motor across the drive gear fitted onto the output shaft.

5. The motor drive unit as claimed in claim 4 , wherein
the brake device includes an electromagnetic brake that establishes a magnetic attraction when energized to engage the brake member with the rotary member.

Assignees

• Toyota Motor Co Ltd
• Alchemica Corp

Inventors

• Isono Hiroshi
• Sugitani Nobuyoshi
• Kubo Aizoh

Classifications

• Y02T10/645

  Cross-Sectional Technologies · mapped topic

• B60L15/2009 Primary

  for braking · CPC title

• H02K7/1025

  using axial electromagnets with generally annular air gap · CPC title

• Y02T10/641

  Cross-Sectional Technologies · mapped topic

• B60L2220/50

  Structural details of electrical machines · CPC title