Spring-Loaded Screwdriver Insert for Multi-Size Screw Openings

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing screw tools lack versatility in accommodating different-sized screwdriver insertion openings, limiting their functionality and efficiency in handling various screw types.

Innovation Solution

A screwdriver with an elongated shaft featuring multiple interchangeable output profiles, each with a spring-loaded insert that can be displaced to fit into different-sized screwdriver openings, allowing for efficient use with screws of varying sizes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a screw tool has a single fixed output profile, then the structure is simple and easy to manufacture, but it cannot accommodate different-sized screwdriver insertion openings

Engineering Contradiction:
Improveaccommodation of different-sized screwdriver insertion openingsVSAvoidstructure of screw tool
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The screw tool is divided into a shaft and multiple interchangeable inserts. Each insert can be independently removed and replaced with another insert of different size, allowing the tool to adapt to different screwdriver insertion openings without redesigning the entire tool structure.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

A single shaft design serves multiple functions by accommodating different inserts. The universal shaft can work with various insert types (hexagonal, square, Torx, etc.) of different sizes, making one tool capable of handling multiple screw types and sizes.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If multiple screw tool sizes are used to handle different screw types, then each tool can be optimized for its specific size, but it requires multiple tools and increases tool inventory complexity

Engineering Contradiction:
Improvehandling of various screw typesVSAvoidnumber of tools required
Core Design Contradiction:
Adaptability or versatilityVSQuantity of substance

Solution Approach 1:

One universal shaft with multiple interchangeable inserts replaces the need for multiple dedicated screw tools. Users only need to keep one shaft and swap inserts as needed, significantly reducing the number of tools required while maintaining the ability to handle various screw types.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

Multiple inserts of different sizes can be stored within the shaft or its holder when not in use. The inserts nest together or stack within the tool handle, allowing users to carry a complete set of different-sized inserts in a single compact tool rather than separate tools.

Inventive Principle:
Principle #7Nested doll (Nesting)

3Ease of operation

If an insert is made fully displaceable in the cavity, then it can be easily inserted and removed, but it may become loose or fall out during operation

Engineering Contradiction:
Improveinsertion and removal of insertVSAvoidretention of insert in cavity
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The insert holder uses elastic elements (springs) to provide dynamic retention. The springs continuously exert force to hold the insert securely in the cavity during operation, while still allowing the insert to be easily pushed in or removed when needed. This creates a balanced system that is both secure and user-friendly.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

Elastic retention elements act as intermediaries between the insert and the cavity. These elements provide the retaining force without directly constraining the insert in a fixed position, allowing easy removal while ensuring secure holding during use.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 screwdriver can efficiently turn screws with four different-sized screwdriver insertion openings using a single tool, enhancing versatility and operational convenience.

Implementation Method 1

The slide insert (19) can be displaced against the restoring force of a spring element (10)... The relaxing compression spring then moves the insert back into the stop position

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

It can be a pre-tensioned compression spring, and in particular a helical compression spring

Methodology Applied
Scientific EffectCompression spring: Spring

Implementation Method 3

The radially projecting stop interacts with a step in the cavity or chambers, preventing the insert from being pushed out of the cavity by the compression spring

Methodology Applied
Scientific EffectMechanical constraint: Mechanical Force

Implementation Method 4

The end face of the insert protruding from the recess contacts the bottom of the screwdriver insertion opening. By applying axial pressure, the insert retracts into the recess

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP4237197B1Screwdriver insert
Publication Date: 2025.12.17 WERA WERKZEUGE GMBH
  • EP4237197B1 patent drawingFigure 1~3
  • EP4237197B1 patent drawingFigure 4~7
  • EP4237197B1 patent drawingFigure 8

AI summary

The present invention relates to a screwing tool comprising an elongate shaft (1) which has, at each of its two ends, an output profile (2, 12) for insertion into a screwing tool insertion opening (23) of a screw (31), and comprising a first insert (19) and a second insert (25), which inserts (19, 25): are each axially slidably arranged for conjoint rotation in a first and second cavity (4, 14) which are open toward an end face (3) of the output profiles (2, 12); each form, by means of their ends protruding from the cavity (4, 14), an output profile (21, 27); when in a position protruding from the cavity, are each supported, by means of a stop, on a counter-stop of the shaft (1); and can, by applying an axial force, be moved into the respective cavity (4, 14) against the restoring force of a spring element (10) arranged in a chamber (7, 8) extending between the first cavity (4) and the second cavity (14). In order to functionally advantageously develop a screwdriver insert, according to the invention, the first cavity (4) and the second cavity (14), forming a first and a second step (15, 15'), transition into the chamber (7, 8), which has a larger internal cross-sectional area than the cavity (4, 14) adjoining same, wherein the first step (15) forms the counter-stop on which the stop of the first insert (19) is supported, and the second step (151) forms the counter-stop of the second insert (25), on which counter-stop the stop (11), which can be elastically deformed radially inwards, of the second insert (25) is supported.