Air-Spring Hammer Mechanism Layout for Lower Tool Vibration

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing power tools with hammer mechanisms experience increased vibration and insufficient hammering force due to mechanical conversion of motor energy, leading to inefficiencies in tools like shovels.

Innovation Solution

A power tool design incorporating a motor with a motor shaft parallel to a hammer axis, utilizing an air spring to convert rotary motion to linear motion, reducing vibration and enhancing kinetic energy transfer through an air spring mechanism.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Force

If a cam mechanism is used to convert rotary motion to linear motion, then the tool accessory can be driven, but vibration of the power tool increases and sufficient hammering force cannot be obtained

Engineering Contradiction:

Improvehammering forceVSAvoidvibration

Core Design Contradiction:

ForceVSObject-affected harmful factors

Solution Approach 1:

The patent replaces the traditional mechanical cam mechanism with an air spring mechanism. The air spring (a pneumatic element) converts rotary motion of the motor shaft into linear reciprocating motion of the hammer element, eliminating the need for mechanical cam followers and reducing vibration while maintaining effective hammering force.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent employs an air spring (pneumatic system) as the core mechanism to convert rotary motion to linear motion. The air spring expands and contracts to drive the hammer element reciprocatingly, providing smooth force transmission and reducing mechanical vibration compared to traditional cam mechanisms.

Inventive Principle:

Principle #29Pneumatics and hydraulics

2Power

If mechanical conversion is used to transmit kinetic energy, then motion can be transmitted, but vibration increases and kinetic energy transmission is insufficient

Engineering Contradiction:

Improvekinetic energy transmissionVSAvoidvibration

Core Design Contradiction:

PowerVSObject-affected harmful factors

Solution Approach 1:

The patent substitutes the mechanical transmission system with a pneumatic air spring mechanism. The air spring directly transmits kinetic energy from the rotating motor shaft to the hammer element through pneumatic pressure changes, achieving more efficient energy transmission with reduced vibration losses.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The air spring acts as an intermediary between the motor shaft and the hammer element. It mediates the energy transmission by converting rotational kinetic energy into pneumatic pressure variations that drive the hammer element, providing smoother and more efficient energy transfer compared to direct mechanical coupling.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Ease of operation

If motor axis is not aligned with hammer axis, then component arrangement is flexible, but user cannot easily apply linear force to the tool accessory

Engineering Contradiction:

Improveease of applying linear forceVSAvoidcomponent arrangement

Core Design Contradiction:

Ease of operationVSDevice complexity

Solution Approach 1:

The patent aligns the motor axis parallel to and coincident with the hammer axis, creating a linear arrangement where all components are positioned along the same longitudinal axis. This one-dimensional alignment simplifies the force application path for the user and reduces the need for complex angular force transformations.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

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 reduces vibration and increases the hammering force, improving operability and efficiency for tasks like digging by aligning components on a straight line and utilizing an air spring for smoother energy transfer.

Implementation Method 1

hammer element 524 that converts rotary motion of the motor shaft 24 to linear motion of the hammer element 524 along a prescribed hammer axis TX by utilizing action of an air spring

Methodology Applied

Scientific EffectAir spring: Spring

Data Source

PatentUS12601138B2Power tool having a hammer mechanism

Publication Date: 2026.04.14 MAKITA CORP

AI summary

A power tool includes a motor, a hammer mechanism, and a housing. The motor has a motor shaft that rotates around a motor axis. The hammer mechanism includes a cylinder and a hammer element adjacent to an air chamber defined within the cylinder and is configured to convert rotary motion of the motor shaft to linear motion of the hammer element along a prescribed hammer axis by utilizing action of an air spring of the air chamber. The housing houses the motor and the hammer mechanism. The motor axis is arranged to be parallel to the hammer axis and to pass through the inside of the cylinder.