Nested Drive Shaft and Planetary Gear Layout for Compact Power Tools
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hand-held power tools face challenges in achieving a compact design while maintaining efficient torque transmission and operational versatility, particularly in cordless configurations.
Innovation Solution
The design incorporates a drive shaft bearing supported by a support element, integrated with the drive shaft, and a transmission system featuring a planetary gear mechanism, which allows for compact size and efficient torque transfer, enabling both cordless and mains-powered operation with reversible rotation and percussive capabilities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If the drive shaft bearing is arranged radially between the drive shaft and the intermediate shaft, then the torque transmission efficiency is improved, but the axial space requirement increases
Solution Approach 1:
The drive shaft bearing is arranged radially between the drive shaft and the intermediate shaft, changing the bearing arrangement from axial to radial dimension. This dimensional shift allows the bearing to support the drive shaft while minimizing axial space occupation, thereby resolving the contradiction between torque transmission efficiency and axial space requirement
2Stability of the object's composition
If the drive shaft protrudes into the intermediate shaft, then the structural integration is improved, but the manufacturing complexity increases
Solution Approach 1:
The drive shaft protrudes into the intermediate shaft, creating a nested structural arrangement where one shaft is partially inserted into another. This nesting provides structural integration and stability while maintaining relatively simple manufacturing processes for each individual shaft component
3Power
If the transmission unit includes a planetary gear mechanism, then the torque multiplication is improved, but the device complexity increases
Solution Approach 1:
The planetary gear mechanism combines multiple gear elements (sun gear, planet gears, and ring gear) into a single integrated transmission unit. This merging of components achieves high torque multiplication through the planetary arrangement while consolidating what would otherwise require multiple separate transmission stages into one compact unit
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution achieves a compact, robust, and versatile hand-held power tool that efficiently transfers torque, supports reversible rotation, and provides percussive functions, enhancing usability and operational efficiency.
Implementation Method 1
The drive shaft bearing can, for example, be designed as a ball bearing, a rolling bearing, or a slide bearing
Implementation Method 2
The transmission can be configured as one planetary transmission, in which case it can, for example, be shiftable
Implementation Method 3
The drive motor can be configured as an electrically commutated drive motor, in particular as at least one electric motor
Data Source
AI summary
A hand-held power tool includes a drive motor with a drive shaft, and a transmission which can be actuated by the drive shaft. The transmission has an intermediate shaft into which the drive shaft at least partially projects. The power tool also includes at least one drive shaft bearing arranged radially between the drive shaft and the intermediate shaft, and a tool holder which can be actuated by the drive shaft. The drive shaft further includes at least one support element, which is designed to support the drive shaft bearing in the direction of the tool holder.