Vehicle Drivetrain Layout With Axially Offset Electric Machines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electric machines used as vehicle drive systems require significant installation space due to their large dimensions, limiting the coaxial arrangement with internal combustion engines and necessitating suboptimal space utilization in vehicles.
Innovation Solution
The electric machines are axially offset, with the smaller starter generator positioned close to the internal combustion engine and the larger drive system machine positioned further away, allowing for optimal use of available space and maintaining sufficient underbody clearance, while maintaining connectivity through flexible mechanisms and transmissions to ensure efficient power transfer without rotation reversal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the first electric machine is arranged coaxially with the internal combustion engine, then the power transfer is efficient, but the installation space is insufficient due to the large outer diameter required for adequate underbody clearance
Solution Approach 1:
The patent transitions from a coaxial arrangement (single dimension) to an axially offset arrangement, where the first electric machine's rotation axis is displaced perpendicular to the engine's crankshaft axis. This dimensional change allows the large-diameter electric machine to be positioned in the lateral direction rather than requiring excessive axial length, thereby resolving the space constraint while maintaining functional connectivity through gear mechanisms
2Area of stationary object
If the first electric machine is positioned far from the internal combustion engine to accommodate its large dimensions, then the installation space is optimized, but the connection complexity increases
Solution Approach 1:
The patent introduces gear mechanisms as intermediary elements between the first electric machine and the transmission system. These gears serve as mediators that bridge the spatial gap created by the axially offset arrangement, enabling power transfer while keeping the connection mechanism relatively simple and manageable rather than requiring complex flexible couplings or long shafts
3Area of moving object
If the axial offset is increased to maximize outer diameter, then the radial installation space is optimized, but the underbody ground clearance is reduced
Solution Approach 1:
The patent optimizes the axial offset parameter to achieve a balance between maximizing the outer diameter for radial space utilization and maintaining sufficient underbody clearance. By carefully selecting the offset distance, the design achieves optimal space utilization without compromising the vehicle's ground clearance requirements
Data Source
AI summary
A drive train for a vehicle includes an internal combustion engine coaxial to a first axis, a first electric machine, and a second electric machine. The first electric machine has larger dimensions than the second electric machine. The second electric machine is connectable to the internal combustion engine. A rotor axis of the first electric machine is axially offset from a rotor axis of the second electric machine. Additionally, the drive train includes a transmission arrangement connectable to a drive output, with the first electric machine being connectable to the transmission arrangement.