Handheld Tool Pole Member Friction Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing pruning tools experience wear and tear due to friction between the inner and outer tubes during telescopic movement, and require precise design to avoid dimensional mismatches, leading to inefficiencies and increased manufacturing and maintenance costs.

Innovation Solution

A handheld tool design featuring a pole member with a cover portion and an elongated tube portion where the outer diameter of the tube is less than the inner diameter of the pole, allowing for reduced friction and eliminating wear and tear, with a sliding member that restricts movement at a predefined distance to maintain stability and prevent dismantling, and a cable system that actuates the implement member.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the inner tube and outer tube are designed with precision to avoid dimensional mismatch, then the reliability of the tool is improved, but the manufacturing complexity and cost increase

Engineering Contradiction:
Improvedimensional compatibilityVSAvoidmanufacturing precision requirements
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

A cable member is introduced as an intermediary element to connect the handle member to the implement member. The cable member allows for telescopic movement between the handle and implement without requiring precise dimensional matching between the pole member and tube portion, thereby reducing manufacturing complexity while maintaining operational reliability

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The design changes the critical dimensional parameter relationship by making the outer diameter of the elongated tube portion less than the inner diameter of the pole member, creating a clearance fit that eliminates the need for precision matching while preventing wear and tear through the sliding member mechanism

Inventive Principle:
Principle #35Parameter changes

2Ease of operation

If the inner tube remains in surface contact with the outer tube during sliding movement, then the ease of operation is improved, but friction causes wear and tear of the tubes

Engineering Contradiction:
Improvesliding movementVSAvoidfriction and wear
Core Design Contradiction:
Ease of operationVSObject-generated harmful factors

Solution Approach 1:

The cable member acts as a mediator that transmits force from the handle member to the implement member through the pole member, enabling operation without direct surface contact between the tube portions. This eliminates friction-induced wear while maintaining operational functionality

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The sliding member is designed as a separate, replaceable component that can be easily replaced if worn. This approach accepts that wear will occur but makes the replacement process simple and cost-effective, avoiding the need for precision-machined replacement parts

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

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 design significantly reduces friction and wear, eliminates dimensional mismatches, and lowers manufacturing and maintenance costs while maintaining tool stability and functionality.

Implementation Method 1

the inner tube remains in a surface contact with the outer tube, during relative movement i.e. sliding movement, of the inner tube. This result in actuation of the pruning mechanism operably connected to the inner tube to perform the pruning operation. Typically, the inner tube remains in a surface contact with the outer tube, during relative movement i.e. sliding movement, of the inner tube. Such relative movement between the inner tube and the outer tube may result in friction, which may lead to wear and/or tear of the inner tube and the outer tube.

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP3579683B1Handheld tool
Publication Date: 2020.12.09 HUSQVARNA AB
  • EP3579683B1 patent drawingFigure 1
  • EP3579683B1 patent drawingFigure 2
  • EP3579683B1 patent drawingFigure 3

AI summary

The present invention relates a handheld tool (100). The handheld tool (100) includes a pole member (102) having a first end (106) and a second end (108). The handheld tool (100) further includes a handle member (128) having holding portion (142) and an elongated tube portion (144). The handheld tool (100) includes a cable member (166) extending through the pole member (102) to connect an implement member (104) with the handle member (128). The second end (108) of the pole member (102) includes a cover portion (126) having an opening (140) of a diameter corresponding to an outer diameter of the elongated tube portion (144). The outer diameter of the elongated tube portion (144) is less than an inner diameter of the pole member (102). The elongated tube portion (144) is provided with a sliding member (160) slidably associated with the pole member (102) for allowing telescopic movement of the elongated tube portion (144) with respect to the pole member (102).