Working Machine Speed Increaser and Reducer for Vibration Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing working machines face a trade-off between maintaining high rotational speed for tool performance and minimizing vibrations, as setting rotational speed to ensure tool performance worsens vibrations, and setting it low to reduce vibrations deteriorates tool performance.

Innovation Solution

Incorporating a speed increaser between the shaft and the front tool, configured to make the rotational speed of the front tool higher than the shaft, while a speed reducer between the shaft and the prime mover lowers the shaft's rotational speed, and using a support system with multiple bearings and springs to stabilize the pipe during extension and contraction, thereby reducing vibrations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the rotational speed of the front tool is set high to ensure work performance, then the work performance is improved, but the rotational speed of the shaft increases and vibrations in the working machine worsen

Engineering Contradiction:

Improvework performance of front toolVSAvoidvibrations in working machine

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The transmission system is segmented into two independent stages: a speed reducer between the prime mover and shaft, and a speed increaser between the shaft and front tool. This segmentation allows the shaft to rotate at a lower speed (reducing vibrations) while the front tool rotates at a higher speed (maintaining work performance) through the speed increaser mechanism.

Inventive Principle:

Principle #1Segmentation

2Object-affected harmful factors

If the rotational speed of the shaft is set low to suppress vibrations, then the vibrations are reduced, but the rotational speed of the front tool decreases and work performance deteriorates

Engineering Contradiction:

Improvevibrations in working machineVSAvoidwork performance of front tool

Core Design Contradiction:

Object-affected harmful factorsVSProductivity

Solution Approach 1:

The speed increaser acts as an intermediary mechanism between the shaft and the front tool. It receives rotational motion from the shaft at a lower speed and transforms it into higher speed rotation for the front tool, thereby decoupling the speed requirements of the shaft (low speed for vibration suppression) and the front tool (high speed for work performance).

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS11707829B2Working machine including speed increaser and speed reducer

Publication Date: 2023.07.25 MAKITA CORP

AI summary

A working machine may include a pipe, a body unit, a tool unit, a shaft, and a speed increaser. The body unit may be disposed at a rear end of the pipe and include a prime mover. The tool unit may be disposed at a front end of the pipe and include a front tool. The shaft may be disposed inside the pipe and be configured to transmit power of the prime mover to the front tool. The speed increaser may be disposed between the shaft and the front tool. The speed increaser may be configured to make a rotational speed of the front tool higher than a rotational speed of the shaft.