Vibration-Split Handheld Power Tool Layout for Low Emissions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Handheld power tools face challenges in achieving compactness and low weight while minimizing vibration and emissions, particularly with two-stroke engines that require additional features like stratified scavenging arrangements, which add complexity and weight.
Innovation Solution
A handheld power tool design featuring a horizontal vibration split with a void space between the handle and engine portions, allowing for a stratified scavenging intake channel and a control device mounted at a specific angle to optimize space usage, reducing vertical height and enabling more efficient fuel injection and emission control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a vibration split is implemented to reduce vibration, then vibration is reduced, but device complexity and design difficulty increase
Solution Approach 1:
The power tool is divided into two separate portions: a handle portion and an engine portion. The engine portion is resiliently suspended to the handle portion via resilient members, creating a vibration split that isolates vibration-generating components from the user's hands while maintaining overall tool functionality.
2Object-generated harmful factors
If additional features like stratified scavenging arrangements are added to reduce emissions, then emission control is improved, but device complexity and weight increase
Solution Approach 1:
The stratified scavenging intake channel is integrated within the existing engine structure, nesting the emission control feature inside the engine portion. This allows the additional emission-reducing component to be accommodated without proportionally increasing overall device complexity or weight.
3Stability of the object's composition
If the control device is mounted perpendicular to the separation plane to maximize stability, then stability is improved, but the vertical height increases
Solution Approach 1:
The control device is mounted at an angle less than 35 degrees relative to the separation plane, orienting it along the longitudinal axis of the tool rather than perpendicular to it. This angular orientation redistributes the control device's spatial footprint, reducing vertical height while maintaining stability through proper alignment with the tool's longitudinal structure.
4Object-affected harmful factors
If the engine portion is resiliently suspended to reduce vibration transmission, then vibration is reduced, but manufacturing complexity increases
Solution Approach 1:
The engine portion is extracted as a separate, independently suspendable module from the handle portion. The resilient members connect these two separate modules, allowing the engine to be pre-assembled and tested independently before final assembly, thereby simplifying the manufacturing process despite the added vibration isolation feature.
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 achieves a compact, lightweight power tool with reduced unburned hydrocarbon emissions and improved fuel efficiency, while maintaining a low vertical height and allowing for additional systems like stratified scavenging, enhancing user comfort and environmental sustainability.
Implementation Method 1
The engine portion is resiliently suspended to the handle portion via a number of resilient members
Data Source
AI summary
A handheld power tool (1) is disclosed comprising a tool (30) and an engine (10) configured to power the tool (30). The power tool (1) comprises a handle portion (4) and an engine portion (6) resiliently suspended to the handle portion (4). The power tool (1) has a void space (12, 12′) between the handle portion (4) and the engine portion (6) extending along a separation plane (Sp). The separation plane (Sp) is transversal to a horizontal centre plane (Hcp) and to a vertical centre plane (Vcp) of the power tool (1). The power tool (1) comprises a control device (28) mounted to the handheld power tool (1) such that the angle (a1) between the separation plane (Sp) and one of two larger sides (s1, s1′) of the control device (28) is less than 35 degrees or is less than 25 degrees.