Elastomeric Overmold Motor Mounts for Power Tool Vibration Isolation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Power tools experience significant vibration transmission during use, which can lead to discomfort and potential damage due to the lack of effective vibration dampening in their housings, particularly when manufactured from materials like plastic.

Innovation Solution

The integration of resilient elastomeric overmold motor mounts within the power tool housing, which are designed to absorb and distribute vibrations by being directly attached to the inner surfaces of the housing shells, providing a snug fit around the motor and projecting inwardly to enhance vibration isolation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the housing is manufactured from rigid molded shell body (plastic), then the structural strength and manufacturability are improved, but vibration transmission to the motor increases

Engineering Contradiction:
Improvestructural strengthVSAvoidvibration transmission
Core Design Contradiction:
StrengthVSObject-affected harmful factors

Solution Approach 1:

The patent introduces elastomeric motor mount members as intermediary elements between the rigid housing and the motor. These mounts act as a mediator that decouples the motor from the housing, allowing the rigid housing to maintain its structural strength while the elastomeric mounts absorb and dampen vibrations, preventing them from transmitting to the motor.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent employs composite construction by combining rigid molded shell bodies for the housing with elastomeric materials for the motor mount members. This composite approach allows each material to perform its optimal function - the rigid housing provides structural strength and the elastomeric mounts provide vibration dampening, resolving the contradiction between strength and vibration transmission.

Inventive Principle:
Principle #40Composite materials

2Object-affected harmful factors

If elastomeric motor mount members are added to the housing, then vibration dampening is improved, but the device complexity increases

Engineering Contradiction:
Improvevibration dampeningVSAvoidhousing structure complexity
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The patent merges the motor mount function directly into the housing structure by integrally forming the elastomeric motor mount members with the rigid molded shell bodies. This integration eliminates the need for separate mounting components and assembly steps, reducing device complexity while maintaining effective vibration dampening.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The elastomeric motor mount members serve multiple functions: they provide vibration dampening, support the motor, and facilitate assembly. This multi-functionality reduces the need for additional components, thereby improving vibration dampening without proportionally increasing device complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Object-affected harmful factors

If the motor mount members project inwardly from the housing, then the vibration isolation is improved, but the manufacturing precision requirements increase

Engineering Contradiction:
Improvevibration isolationVSAvoidmount member alignment precision
Core Design Contradiction:
Object-affected harmful factorsVSManufacturing precision

Solution Approach 1:

The patent utilizes the elastomeric material's ability to deform and conform through parameter changes in its physical state. The motor mount members are designed to compress and adapt to the motor's position and tolerances, reducing the need for high manufacturing precision while maintaining effective vibration isolation.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The elastomeric motor mount members provide dynamic adaptation to manufacturing variations. Their resilient nature allows them to compensate for minor misalignments and dimensional variations, enabling effective vibration isolation without requiring extremely tight manufacturing tolerances.

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

The elastomeric overmold motor mounts significantly reduce vibration transmission between the housing and motor, enhancing user comfort and tool durability by effectively absorbing and distributing vibrational loads, thereby reducing the impact of accidental drops.

Implementation Method 1

The elastomeric overmold motor mounts significantly reduce vibration transmission between the housing and motor, enhancing user comfort and tool durability by effectively absorbing and distributing vibrational loads

Methodology Applied
Scientific EffectVibration dampening: Damping

Implementation Method 2

resilient (e.g., elastomeric or rubber) overmold motor mounts that can reduce vibration transmitted between the housing and motor

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 3

effectively absorbing and distributing vibrational loads, thereby reducing the impact of accidental drops

Methodology Applied
Scientific EffectImpact absorption: Damping

Data Source

PatentEP2726255B1Power tools with housings having integral resilient motor mounts
Publication Date: 2018.09.19 INGERSOLL RAND CO
  • EP2726255B1 patent drawingFigure 1A~1B
  • EP2726255B1 patent drawingFigure 2
  • EP2726255B1 patent drawingFigure 3

AI summary

Power tool housing shells that matably attach to each other and define an interior cavity that is sized and configured to encase at least a motor associated with a power train for a power tool. Each housing shell is a substantially rigid molded shell body. Each housing shell inner surface includes at least one overmold motor mount member of a resilient material directly, integrally attached to an inner surface of the respective housing shell.