Dental Abrasive Assembly Resilient Mandrel Retention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing dental abrasive assemblies face challenges in achieving low engagement and disengagement forces while preventing wobbling and slippage of the abrasive member during high-speed rotation, and in tolerating manufacturing variability and wear of components.
Innovation Solution
The assembly combines a resilient abrasive member with a compressible mandrel, featuring a bulbous working end divided by elongated slots, allowing for cooperative deflection and increased frictional engagement, which compensates for manufacturing tolerances and extends operational lifetime.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the engagement and disengagement forces are made low to allow easy user replacement of the head component, then the ease of operation is improved, but the reliability deteriorates because the abrasive member may wobble or unintentionally dislodge from the power tool
Solution Approach 1:
The mandrel incorporates a resilient bulbous portion that can dynamically deform under engagement force and then elastically recover to maintain retention. This dynamic behavior allows the system to achieve both easy engagement (through initial deformation) and secure retention (through elastic recovery), resolving the contradiction between ease of operation and reliability
Solution Approach 2:
The system changes the physical state of the mandrel's bulbous portion from rigid to resilient, allowing it to deform and recover. This parameter change enables the mandrel to provide both low engagement forces (through deformation) and high retention forces (through elastic recovery), simultaneously satisfying ease of operation and reliability requirements
2Reliability
If the mechanical coupling between the head and drive components is made strong to efficiently drive the head portion at high rotational speeds without slippage, then the reliability is improved, but the ease of operation deteriorates because the engagement and disengagement forces become too high
Solution Approach 1:
The resilient bulbous portion provides dynamic coupling that adapts to operational conditions. During high-speed rotation, the elastic recovery maintains strong frictional engagement to prevent slippage, while during engagement/disengagement, the material can deform to reduce required forces, thus resolving the contradiction between driving efficiency and ease of replacement
3Manufacturing precision
If the abrasive member and mandrel are made rigid to maintain precise dimensional tolerances, then the manufacturing precision is improved, but the reliability deteriorates due to inability to tolerate manufacturing variability and wear
Solution Approach 1:
The mandrel's bulbous portion changes from a rigid structure to a resilient one, allowing it to deform and accommodate dimensional variations. This enables the system to tolerate manufacturing variability and wear while maintaining reliable engagement, resolving the contradiction between manufacturing precision and reliability
Solution Approach 2:
The resilient material provides a cushioning effect that compensates for dimensional variations and wear before they become critical. This beforehand cushioning allows the system to maintain reliable operation despite manufacturing tolerances and wear, resolving the contradiction between precision requirements and tolerance to variability
Data Source
Figure 1~2
Figure 3~4
Figure 5a~5b
AI summary
Provided are abrasive assemblies and related methods that combine a head portion including an integral abrasive member and a drive portion including a resilient cylindrical mandrel. The abrasive member has a receptacle that is complemental to a working end of the mandrel when both members are relaxed. As the abrasive member engages to, or disengages from, the mandrel, the receptacle resiliently expands and the working end of the mandrel resiliently compresses, each in cooperation with the other. Optionally, the abrasive member is maintained in compression in both directions parallel and perpendicular to the longitudinal axis of the mandrel. Advantageously, these assemblies provide for superior retention and slip resistance, ease-of-use, and high manufacturing tolerances.