Rotary Power Tool Vibration Damping Coupler
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-speed electric power tools experience significant vibration due to the longer rotor and output shafts, which can shake the tool and reduce user comfort and precision during operation.
Innovation Solution
A power tool design featuring a coupler with a dampening portion between the motor shaft and spindle to attenuate vibration, and additional dampers between the inner and outer spindle housings to reduce vibration transmission to the user.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If a longer rotor shaft and output shaft are used in high-speed electric power tools, then the tool can achieve high operating speeds, but the shaft tends to vibrate at resonant frequencies that shake the tool
Solution Approach 1:
The patent introduces a coupler as an intermediary component between the motor shaft and the spindle. This coupler includes a dampening portion that acts as a mediator to reduce vibration transmission while still allowing torque transmission, thus resolving the contradiction between maintaining high operating speed and reducing harmful vibrations.
Solution Approach 2:
The patent converts the harmful vibration energy into beneficial damping through the coupler's dampening portion. By incorporating materials or structures that dissipate vibrational energy, the system transforms the harmful resonant vibrations into heat or other non-harmful forms, thereby reducing the shaking effect while maintaining high-speed operation.
2Object-affected harmful factors
If dampers are added between the inner and outer spindle housings to reduce vibration transmission, then user comfort improves, but device complexity increases
Solution Approach 1:
The patent employs a nested structure where the inner spindle housing is positioned within the outer spindle housing, and dampers are integrated between these nested components. This nesting approach allows vibration isolation without requiring separate external damping systems, thereby reducing overall structural complexity while still achieving vibration reduction.
Solution Approach 2:
The patent merges the vibration damping function with the existing spindle housing structure by integrating dampers into the housing design itself. Rather than adding completely separate damping components, the dampers are combined with the housing structure, reducing the number of discrete parts and simplifying the overall device complexity.
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 effectively reduces vibration, enhancing user comfort and operational stability by minimizing the transfer of resonant frequencies from the spindle to the handle, thereby improving tool handling and precision.
Implementation Method 1
a coupler positioned between the motor shaft and the spindle for transmitting torque therebetween, the coupler having a dampening portion configured to attenuate vibration of the spindle
Implementation Method 2
A damper positioned between the inner spindle housing and the outer spindle housing. The damper is configured to attenuate transmission of vibration from the inner spindle housing to the outer spindle housing
Data Source
AI summary
A power tool includes a main housing defining a handle, a spindle housing coupled to the main housing, and a drive mechanism positioned at least partially within the main housing and the spindle housing. The drive mechanism includes a motor having a motor shaft, a spindle having a first end and a second end defining a tool holder, the tool holder configured to receive a tool bit, and a coupler positioned between the motor shaft and the spindle for transmitting torque therebetween, the coupler having a recess defined therein. A spindle lock is coupled to the spindle housing, wherein the spindle lock is biased towards an unlocked position and movable toward a locked position in which the spindle lock is engaged with the recess to restrict rotation of the spindle and the motor shaft.