Integrated Drive Housing Layout for Motor Shaft Noise Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Integrated drive devices for vehicles, such as those described in Japanese Unexamined Patent Application Publication No. 2014-24489, often suffer from noise issues due to noise transmission through the motor shaft.
Innovation Solution
The drive device incorporates a configuration where the motor, gear unit, and power conversion unit are housed in separate cases - a motor case, a first case for the gear unit, and a second case for the power conversion unit. The first and second cases are fixed to one side of the motor case, covering the central axis of the motor shaft and reducing noise emission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the motor, gear unit, and power conversion unit are integrated in a single housing, then device complexity is reduced and compactness is improved, but noise transmission through the motor shaft increases
Solution Approach 1:
The housing is divided into a first housing for the gear unit and a second housing for the power conversion unit, with the motor shaft extending through both. This segmentation allows noise isolation while maintaining structural integration, resolving the contradiction between compactness and noise reduction.
2Ease of operation
If the motor shaft is exposed at the end face, then ease of operation is improved, but noise emission from the end face increases
Solution Approach 1:
The second housing acts as an intermediary structure that covers the motor shaft end face while allowing the shaft to extend through it. This mediator structure isolates the noise source (meshing point) from the external environment while maintaining shaft accessibility for operation.
3Ease of operation
If the meshing point between gears is exposed, then ease of operation is improved, but noise emission increases
Solution Approach 1:
The first housing encloses the gear unit and covers the meshing point between gears, isolating the noise source. The segmented housing structure allows the gears to remain accessible for operation while preventing noise emission to the external environment.
4Reliability
If the cases are fixed in a liquid-tight manner, then reliability is improved, but device complexity increases
Solution Approach 1:
The first and second housings are fixed together in a liquid-tight manner, merging their sealing functions into a unified structure. This combining approach achieves reliable liquid-tight sealing while avoiding the need for separate sealing mechanisms, thus not increasing overall device complexity.
Data Source
AI summary
A drive device including a motor, a motor case, a first case, and a second case is provided. The motor includes a motor shaft. The motor case is configured to house the motor. The first case is configured to house a gear unit mechanically connected to the motor. The second case is configured to house a power conversion unit electrically connected to the motor. The first case and the second case are fixed to one side of the motor case in the axial direction of the motor shaft. The central axis of the motor shaft is covered by the first case and the second case in the axial direction of the motor shaft.