Impact Tool Housing Segmentation for Vibration Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing impact tools experience operability issues due to fluctuations in the distance between the hands holding the front and rear housing shells during hammering operations, affecting stability and efficiency.

Innovation Solution

An impact tool with a single body housing that integrates the motor and driving mechanism housings, featuring a biasing member to reduce vibration transmission and maintain a constant distance between handholds, utilizing a guide member and swinging mechanism for axial motion, and a rotation transmitting mechanism for mode switching between hammering and drilling operations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If the motor housing and driving mechanism housing are separately arranged and connected via a compression spring, then the driving mechanism can move with respect to the body housing to reduce vibration transmission, but the distance between the hands holding the impact tool fluctuates during hammering operation, impairing operability

Engineering Contradiction:
Improvevibration transmissionVSAvoidoperability
Core Design Contradiction:
Object-affected harmful factorsVSEase of operation

Solution Approach 1:

The housing is divided into a motor housing region and a driving mechanism housing region that are movable with respect to each other, allowing independent movement of the driving mechanism to reduce vibration while keeping the motor housing stable for user holding

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

A biasing member (compression spring) is introduced as an intermediary element between the motor housing and driving mechanism housing, enabling controlled relative movement that reduces vibration transmission while maintaining overall structural integrity and consistent handhold positioning

Inventive Principle:
Principle #24Intermediary (Mediator)

2Ease of operation

If the motor housing and driving mechanism housing are fixedly connected, then the distance between hands remains constant improving operability, but vibration from the driving mechanism is transmitted to the body housing

Engineering Contradiction:
ImproveoperabilityVSAvoidvibration transmission
Core Design Contradiction:
Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The connection between motor housing and driving mechanism housing is made dynamic rather than fixed, allowing the driving mechanism housing to move relative to the motor housing during operation to reduce vibration transmission while maintaining stable overall dimensions for user comfort

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

Enhances operability by stabilizing the tool during hammering, reducing vibration transmission, and allowing for consistent hand positioning, thereby improving user control and efficiency in both hammering and drilling tasks.

Implementation Method 1

transmission of vibration from the driving mechanism to the body housing is reduced by elastic deformation of the biasing member

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Data Source

PatentEP3156185B1Impact tool
Publication Date: 2024.03.20 MAKITA CORP
  • EP3156185B1 patent drawingFigure 1
  • EP3156185B1 patent drawingFigure 2
  • EP3156185B1 patent drawingFigure 3

AI summary

[Problem] To provide a technology for improving the usability of an impact tool. [Solution] A hammer drill (100) has a main housing (101) in which a motor housing (103) is united with a gear housing (105). An electric motor (110) is fixed in the motor housing (103). Meanwhile, a movement-converting mechanism (120) that is the impact mechanism section, an impact element (140) and a tool holder (159) are housed in the gear housing (105) so as to be capable of moving relative to the gear housing (105). During impact work, the impact mechanism section, on which the biasing force of a coil spring (171) is acting, moves relative to the gear housing (105) and vibrations generated by the impact work are reduced.