EV Drive Unit Layout With Overlapping Gear and Inverter
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle drive apparatuses have large dimensions in the axial view due to the placement of power electronic devices over both the electric motor and transmission apparatus, leading to a desire for a technology that reduces these dimensions.
Innovation Solution
The vehicle drive apparatus is designed with the first output member placed between the rotating electrical machine and the inverter device, allowing the rotating electrical machine and inverter device to be positioned closer together, and the output gear is placed to overlap both, effectively reducing the size in both directions by utilizing overlapping space.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If the power electronic device is placed over both the electric motor and transmission apparatus, then the placement regions of all components are covered, but the dimensions of the entire electric drive unit in axial view become relatively large
Solution Approach 1:
The patent repositions the power electronic device from a planar arrangement (over both motor and transmission) to a three-dimensional arrangement where it is placed on the side of the motor shaft in the axial direction. This dimensional change allows the inverter device to overlap with the motor in axial view while being physically separated, effectively utilizing vertical space to reduce the footprint in the axial plane.
Solution Approach 2:
The inverter device is positioned within the radial space of the motor, specifically on the side of the motor shaft, allowing it to be nested within the overall motor envelope. This nesting approach enables the power electronic device to share space with the motor without increasing the overall axial dimensions, as the inverter fits within the radial boundary of the motor structure.
2Area of moving object
If the rotating electrical machine and inverter device are placed close to each other to reduce size, then the axial view dimensions are reduced, but the placement becomes more complex
Solution Approach 1:
The patent divides the power transmission path into distinct segments: the motor shaft, the transmission mechanism, and the output shaft. By placing the inverter device on the motor shaft side rather than over the transmission mechanism, the design segments the placement zones, allowing each component to occupy its own dedicated space while maintaining close proximity for compactness.
Solution Approach 2:
The motor shaft serves as an intermediary structure that hosts both the motor and the inverter device. By using the motor shaft as the mounting base for the inverter, the patent creates a natural intermediary platform that simplifies the placement configuration compared to trying to position the inverter directly over the transmission mechanism or output shaft.
Data Source
Figure 1~2
Figure 3
Figure 4~5
AI summary
A transmission mechanism is provided with an output gear (30) drivingly coupled to at least one of a pair of output members (6) and placed coaxially with the pair of output members (6). A direction in which a rotating electrical machine (1) and an inverter device (90) are arranged side by side in an axial view is defined as a first direction (X). A direction perpendicular to both an axial direction and the first direction (X) is defined as a second direction (Y). A first output member (61) that is one of the pair of output members (6) is placed between the rotating electrical machine (1) and the inverter device (90) in the first direction (X), at a position in the second direction (Y) where both the rotating electrical machine (1) and the inverter device (90) are placed. The output gear (30) is placed in such a manner as to overlap each of the rotating electrical machine (1) and the inverter device (90) in the axial view.