Chuck Depth Stop With Felt Sliding Element

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing screwing tools with depth stops often leave marks on sensitive workpiece surfaces due to friction, compromising aesthetic quality, especially when high axial pressure is applied.

Innovation Solution

A chuck with a depth stop featuring a sliding element made of felt, which protrudes with fibers to prevent marking, is reversibly connected to the stop sleeve using an adhesive layer, allowing for easy replacement and adjustment, and includes a mechanism for decoupling the screwing tool from the drive shaft to prevent further insertion once the desired depth is reached.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a hard stop surface is used to provide precise depth control, then positioning accuracy is improved, but the workpiece surface is marked or damaged

Engineering Contradiction:
Improvedepth control precisionVSAvoidworkpiece surface marking
Core Design Contradiction:
Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The patent changes the material parameter of the stop surface from hard (metal, plastic) to soft (felt, textile fibers), transforming the interaction mechanism from friction-based marking to fiber-based sliding without marking, thus resolving the contradiction between precision and surface protection

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent uses a composite structure combining a rigid stop sleeve for positioning with a soft felt sliding element for surface contact, creating a composite material system that simultaneously provides precise depth control and protects the workpiece surface from marking

Inventive Principle:
Principle #40Composite materials

2Stability of the object's composition

If high axial pressure is applied to ensure firm contact with the workpiece, then positioning stability is improved, but surface marking increases

Engineering Contradiction:
Improvepositioning stabilityVSAvoidsurface marking
Core Design Contradiction:
Stability of the object's compositionVSObject-affected harmful factors

Solution Approach 1:

The patent changes the contact pressure distribution by using a soft felt material that distributes the axial pressure over a larger area and prevents concentrated stress points, maintaining positioning stability while avoiding surface marking

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The felt sliding element acts as an intermediary between the hard stop sleeve and the workpiece surface, mediating the force transmission to prevent direct contact between hard surfaces and the workpiece, thus eliminating marking while maintaining stability

Inventive Principle:
Principle #24Intermediary (Mediator)

3Device complexity

If the sliding element is permanently fixed to the stop sleeve, then structural simplicity is improved, but adaptability and replaceability are reduced

Engineering Contradiction:
Improvestructural simplicityVSAvoidsliding element replaceability
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The patent segments the depth stop system into a reusable stop sleeve and replaceable sliding elements, allowing different sliding elements to be exchanged for different applications while keeping the main body simple and standardized

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent creates a dynamic system where the sliding element can be removed and replaced based on different workpiece requirements, transforming the static fixed connection into a flexible replaceable connection that adapts to different needs

Inventive Principle:
Principle #15Dynamics

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 felt sliding element allows for screwing without leaving marks on the workpiece surface, maintaining aesthetic quality and enabling precise screw placement without damaging the surface, while the decoupling mechanism prevents over-screwing.

Implementation Method 1

The sliding element is preferably reversibly connected to the end face of the stop sleeve with an adhesive layer

Methodology Applied
Scientific EffectAdhesion: Adhesive

Implementation Method 2

the stop sleeve is displaceable against the restoring force of a spring relative to the shaft section or a central element connected to the shaft section

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 3

The material has the property of being able to slide on the surface of the workpiece without leaving marks

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP3231559B1Chuck with adjustable depth stop
Publication Date: 2019.05.22 WERA WERKZEUGE GMBH
  • EP3231559B1 patent drawingFigure 1
  • EP3231559B1 patent drawingFigure 2~4
  • EP3231559B1 patent drawingFigure 5~8

AI summary

The invention relates to a chuck with a depth stop comprising a drive shaft (3), a receptacle (13) for receiving a tool (2), and a stop surface (11) for depth-limiting a stop sleeve (4) arranged radially away from the receptacle (13) on the surface (16') of a workpiece (16) with respect to a rotational axis defined by the drive shaft (3) and/or the receptacle (13). The stop surface (11) is formed by a first broad side surface (10') of a sliding element (10) made of felt and designed as an annular body, which is attached to the end face (8) of the stop sleeve (4) by means of an adhesive layer (9) with a second broad side surface (10") pointing away from the contact surface (11), wherein the outer diameter of the sliding element (10) is larger than the outer diameter of the end face (8).A radially inner circumferential surface (22) of the sliding element (10) can abut a contact surface (20) of an annular extension (19).