Differential Support Plate Layout for Compact EV Transmissions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a need for further miniaturization of power transmission devices in electric automobiles, particularly in the design of components like the differential mechanism and planetary gear systems, to optimize space usage and efficiency.
Innovation Solution
The power transmission device incorporates a bearing, differential mechanism, a case housing the mechanism, a pinion gear supported by the case, a wall part overlapping the case, a plate supporting the case with a bearing interposed, and a parking pawl fixed to rotate on the plate, allowing for compact arrangement and reduced size without compromising functionality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the power transmission device uses conventional layout with separate support structures for differential mechanism and parking pawl, then the structural integrity and functionality are maintained, but the device size increases and miniaturization is hindered
Solution Approach 1:
The patent combines the support function for both the differential mechanism and parking pawl into a single integrated plate structure. The plate serves multiple functions: supporting the differential mechanism via bearing, providing rotation support for the parking pawl, and acting as a structural intermediary between the case and wall part. This merging of support functions reduces the number of separate components and enables device miniaturization.
Solution Approach 2:
The plate is designed as a multi-functional component that simultaneously: (1) supports the differential mechanism through bearing interposition, (2) provides a rotation support structure for the parking pawl, (3) transmits loads between the case and wall part, and (4) defines the spatial relationship between various components. This multi-functionality reduces overall device complexity while enabling compact design.
2Length of moving object
If the parking pawl is positioned far from the differential mechanism to ensure proper operation, then the functionality is maintained, but the radial dimension increases
Solution Approach 1:
The patent repositions the parking pawl support function to the plate structure rather than using a separate radial support component. By utilizing the plate's extension in the axial direction and its radial positioning relative to the differential mechanism, the design achieves compact radial dimensions while maintaining adequate operational clearance through the plate's structural geometry.
3Device complexity
If the case is directly supported by the wall part without an intermediate plate, then the structure is simpler, but the parking pawl cannot be properly positioned and supported
Solution Approach 1:
The plate serves as an intermediary component between the case and wall part, enabling the parking pawl to be properly supported and positioned. The plate's intermediate position allows the parking pawl to rotate at an optimal location that ensures proper engagement with the differential mechanism while maintaining compact overall dimensions.
Data Source
AI summary
A power transmission device includes a bearing, a differential mechanism, a case that houses the differential mechanism, a pinion gear supported by the case, a wall part that overlaps the case in an axial direction, a plate that is provided between the wall part and the case in the axial direction, and that supports the case with the bearing being interposed, and a parking pawl that is rotatably fixed to the plate in a position that overlaps the plate in the axial direction.