Wood Screw With Segmented Auxiliary Threads For Hard Material Insertion

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional screws face difficulties in being inserted into harder objects due to their pointed ends, and existing solutions like teeth and grooves do not effectively address the issue of material removal and insertion ease.

Innovation Solution

A wood screw design featuring a primary thread with an initial part extending into a conical end, accompanied by first and second auxiliary threads, which carve material away and create channels for efficient removal, reducing the risk of object splitting and facilitating insertion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If conventional screws with pointed ends are used, then insertion into softer objects is possible, but insertion into harder objects becomes very difficult

Engineering Contradiction:
Improveease of insertionVSAvoidinsertion capability into hard objects
Core Design Contradiction:
Ease of operationVSStrength

Solution Approach 1:

The screw thread is segmented into multiple distinct parts: a first auxiliary thread, a second auxiliary thread, and a primary thread. Each segment performs a specific function - the auxiliary threads initially carve material away to create a pilot hole, while the primary thread provides the final fastening. This segmentation allows the screw to progressively penetrate harder materials without requiring excessive insertion force.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The first and second auxiliary threads perform preliminary material removal before the primary thread engages. By pre-carving a channel through the harder object, the auxiliary threads reduce the resistance that the primary thread would otherwise encounter, making insertion into hard objects feasible without pre-drilling.

Inventive Principle:
Principle #10Preliminary action

2Productivity

If teeth are added to helical threads to remove material faster, then insertion into harder objects is facilitated, but the screw structure becomes more complex

Engineering Contradiction:
Improvematerial removal rateVSAvoidscrew structure complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

Different parts of the screw thread have different geometries and functions. The auxiliary threads have specific pitch and depth characteristics optimized for material removal, while the primary thread has characteristics optimized for fastening. This local differentiation of thread properties allows efficient material removal without adding teeth or other complex features to the entire screw structure.

Inventive Principle:
Principle #3Local quality

3Loss of substance

If a groove with cutting edges is added to remove loosened material, then material removal is improved, but the screw design becomes more complicated

Engineering Contradiction:
Improvematerial removal efficiencyVSAvoidscrew design complexity
Core Design Contradiction:
Loss of substanceVSDevice complexity

Solution Approach 1:

The screw design extracts the material removal function from a separate groove structure and integrates it directly into the thread geometry itself. The auxiliary threads are configured to naturally create and clear material channels as they engage the workpiece, eliminating the need for additional grooves or cutting edges while maintaining effective material ejection.

Inventive Principle:
Principle #2Taking out (Extraction)

4Ease of operation

If multiple threads are added to carve material away and create channels, then insertion ease is improved, but the manufacturing complexity increases

Engineering Contradiction:
Improveinsertion easeVSAvoidmanufacturing complexity
Core Design Contradiction:
Ease of operationVSEase of manufacture

Solution Approach 1:

The multi-threaded design serves multiple functions simultaneously: the auxiliary threads carve material away, create pilot holes, and form channels for material ejection, while the primary thread provides the final fastening. This consolidation of multiple functions into a single integrated thread structure simplifies manufacturing compared to adding separate components for each function.

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

Data Source

PatentEP3387272B1Improved wood screw
Publication Date: 2020.01.15 PGB ASIA LTD
  • EP3387272B1 patent drawingFigure 1~2.2
  • EP3387272B1 patent drawingFigure 3.1~3.4
  • EP3387272B1 patent drawingFigure 4~5.2

AI summary

The present invention relates to a wood screw (1) provided to be screwed into an object, wherein the screw (1) comprises a screw head (2), a cylindrical shank (3) around which a primary thread (6) helically extends and a conical end part (4) ending in a tip (5). The primary thread (6) comprises an initial part (7) extending in the direction of the tip (5) of the screw (1), which initial part (7) starts in the conical end part (4), and the screw (1) further comprises a first (8) and a second (9) auxiliary thread, wherein the first (8) and second (9) auxiliary threads extend over at least a first and a second partial length, respectively, of the conical end part (4), and wherein the initial part (7) of the primary thread (6) extends at least partially into the zone delimited by the end (10) of the first auxiliary thread (8) and the start (11) of the second auxiliary thread (9).