Spindle Lock Assembly with Segmented Engagement Members
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional spindle lock assemblies in power tools are cumbersome and inconvenient, requiring substantial rotation of the spindle and often necessitating the use of a wrench, with limited angular zones and painful button depression, leading to inefficiency and discomfort.
Innovation Solution
A spindle lock assembly with multiple engagement members spaced less than 180 degrees apart, allowing for easier alignment and engagement, combined with a button and mount design that reduces finger pressure and risk of pinching, enabling efficient locking and unlocking of the spindle with minimal rotation and ergonomic comfort.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional spindle lock assembly with one hole is used, then the spindle can be locked against rotation, but the spindle needs to be rotated substantially about the spindle axis before the pin aligns with and enters the hole
Solution Approach 1:
The single hole in the spindle is segmented into multiple holes (first hole and second hole) spaced apart from each other. The pin can engage with either hole to lock the spindle, providing multiple engagement positions and reducing the rotation needed to achieve locking.
2Reliability
If a wrench is used to rotate the collet nut about the spindle axis, then the collet nut can be engaged or disengaged, but the process is cumbersome and time consuming, especially when surrounding space is limited
Solution Approach 1:
The engagement process is segmented into multiple discrete steps corresponding to the multiple holes. The user can engage or disengage the collet nut by aligning the pin with different holes in sequence, making the process more manageable and less time-consuming than continuous rotation with a wrench.
Solution Approach 2:
The system transitions from a static single-hole design to a dynamic multi-hole configuration, allowing the pin to engage at different positions. This dynamic engagement approach enables flexible operation and reduces the time needed for collet nut engagement or disengagement.
3Reliability
If the button in the spindle lock assembly is small and biased with substantial force, then the spindle can be locked, but the button is painful to depress and can cause skin pinching
Solution Approach 1:
The button structure is segmented with a recessed portion that creates a larger effective pressing area. The biasing force is distributed across this larger area rather than concentrated on a small surface, reducing pressure intensity and preventing skin pinching while maintaining reliable locking.
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 simplifies the locking and unlocking process, reducing the need for extensive spindle rotation and minimizing user discomfort, allowing for more efficient operation and improved ergonomics during tool use.
Implementation Method 1
a biasing member (80) that biases the button member (66) away from the spindle assembly (15)
Data Source
AI summary
A power tool includes a spindle assembly supported for rotation about an axis. The spindle assembly includes a plurality of engagement members, and at least two of the engagement members are disposed in spaced relationship less than one hundred eighty degrees from each other with respect to the axis of the spindle assembly. The power tool also includes a spindle lock assembly that selectively engages at least one of the plurality of engagement members to lock the spindle assembly against rotation about the axis.