Floating Ring Magnet Bit Holder for Fastener Stability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional quick-release chucks for power and hand tools face challenges in achieving rapid, convenient, and versatile bit changes, particularly in accommodating different fastener head configurations and bit lengths within industry tolerances, while maintaining stability during installation.

Innovation Solution

A quick-change bit holder with a floating ring magnet that supports a hex-shaped bit, allowing the magnet to float forward to engage and stabilize fasteners, and rearward to facilitate easy bit removal, utilizing a spring-biased retraction collar and a floating sleeve mechanism to ensure secure retention and easy exchange.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If a conventional quick-release chuck uses detent balls or spring biased clips to retain bits, then the bit retention mechanism is simple and reliable, but the speed and convenience of bit insertion and removal is insufficient

Engineering Contradiction:
Improvebit change speedVSAvoidchuck mechanism complexity
Core Design Contradiction:
SpeedVSDevice complexity

Solution Approach 1:

The patent replaces traditional mechanical retention mechanisms (detent balls, spring clips) with a magnetic field-based retention system. The ring magnet assembly generates magnetic force to retain the fastener on the tool bit, eliminating the need for complex mechanical engagement components and enabling faster, one-handed bit changes.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the retention mechanism from mechanical contact forces to magnetic field forces. By adjusting magnetic field strength and the floating position of the ring magnet assembly, the system achieves rapid bit retention without complex mechanical structures, resolving the contradiction between speed and complexity.

Inventive Principle:
Principle #35Parameter changes

2Adaptability or versatility

If a ring magnet assembly is fixed at the rear end of the shaft, then the structure is simple, but the magnet cannot effectively engage and stabilize fasteners of different head configurations and bit lengths

Engineering Contradiction:
Improvefastener accommodation capabilityVSAvoidmagnet assembly structure
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent makes the ring magnet assembly movable along the shaft by allowing it to float on magnetic repulsion from a like-poled magnet at the rear end. This dynamic positioning enables the magnet to adapt to different fastener head configurations and bit lengths, achieving versatility without complex adjustment mechanisms.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent introduces a second magnet at the rear end of the shaft as an intermediary element. This magnet creates a magnetic field that repels the ring magnet assembly, allowing it to float and position itself optimally for engaging different fastener types, thereby achieving adaptability through magnetic interaction rather than mechanical linkages.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Stability of the object's composition

If the ring magnet assembly is allowed to float forward to engage fasteners, then fastener stabilization is improved, but the mechanism for rapid bit removal becomes more complex

Engineering Contradiction:
Improvefastener stability during installationVSAvoidmagnet assembly mechanism
Core Design Contradiction:
Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The patent enables the ring magnet assembly to self-position along the shaft through magnetic repulsion forces. The assembly automatically floats forward to engage fasteners and can be rapidly repositioned by the user without requiring complex mechanical release mechanisms, achieving both stability and ease of operation.

Inventive Principle:
Principle #25Self-service

4Ease of operation

If a floating sleeve supports the ring magnet, then the magnet can move freely to engage fasteners, but the retention force may be insufficient without additional mechanical constraints

Engineering Contradiction:
Improveone-handed bit change capabilityVSAvoidbit retention reliability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The patent merges magnetic retention forces with mechanical retention features. The ring magnet assembly provides magnetic holding force while the shaft's reduced diameter region between shoulders provides mechanical constraint, creating a hybrid retention system that ensures both ease of operation and reliable bit retention.

Inventive Principle:
Principle #5Merging (Combining)

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

Enables rapid one-handed bit changes across various fastener configurations and bit lengths, providing stable engagement and reduced wobble during installation, while ensuring easy removal without leaving the bit holder.

Implementation Method 1

a ring magnet assembly movably disposed at said second end of said shaft to magnetize a fastener to retain the fastener to the working region of the tool bit

Methodology Applied
Scientific EffectMagnetism: Magnetism

Implementation Method 2

A second ring magnet is disposed at a rear end portion of the floating sleeve, wherein the first and second ring magnets are arranged with their poles opposing one another such that the floating sleeve is moveable freely along a length of the tool bit

Methodology Applied
Scientific EffectMagnetic repulsion: Ion Repulsion/Attraction

Data Source

PatentEP3834990B1Tool bit
Publication Date: 2024.06.26 BLACK & DECKER CORP
  • EP3834990B1 patent drawingFigure 1~2
  • EP3834990B1 patent drawingFigure 3~5
  • EP3834990B1 patent drawingFigure 6~7

AI summary

A tool bit comprising a shaft having a shank at a first end and a working region disposed at a second end. The shaft has a shaft section between said shank and the working region with a reduced diameter region disposed between two shoulders. The reduced diameter region provides a torsion zone that allows the shaft section to twist to absorb forces while the tool bit is being used to drive a fastener. A ring magnet assembly is movably disposed at the second end of the shaft to magnetize a fastener to retain the fastener to the working region of the tool bit.