Impact Wrench Housing Layout for Cooling and Vibration Isolation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing impact wrenches used in railway construction and maintenance are physically demanding, noisy, and prone to mechanical vibrations and damage from exposure to harsh environmental conditions, leading to operator fatigue and equipment deterioration.

Innovation Solution

A portable impact wrench with an electric motor and battery, featuring an anti-vibration system with damping elements and a ventilation system that separates the motor compartment from the electronic control system using a heat sink, to reduce mechanical stress and protect components from dust and moisture.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If forced ventilation is used to cool the motor, then the motor overheating is prevented, but dust and water are sucked into the housing damaging electrical components

Engineering Contradiction:
Improvemotor temperatureVSAvoidelectrical components protection
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The housing is divided into a first housing portion containing the motor and a second housing portion containing electrical components, separated by a partition wall. This segmentation allows the motor to be ventilated independently while protecting electrical components from dust and water ingress.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The electrical components are extracted from the motor housing space and placed in a separate second housing portion. This extraction removes the vulnerable electrical components from the path of incoming dust and water while maintaining motor cooling functionality.

Inventive Principle:
Principle #2Taking out (Extraction)

2Adaptability or versatility

If the wrench is used in harsh environmental conditions, then the operational versatility is improved, but the mechanical and electrical components deteriorate faster

Engineering Contradiction:
Improveoperational conditionsVSAvoidcomponent durability
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

A waterproof membrane is integrated into the partition wall between the motor and electrical components housing portions. This membrane allows the wrench to operate in harsh environments by preventing water and dust ingress while maintaining structural integrity and component protection.

Inventive Principle:
Principle #30Flexible shells and thin films

Solution Approach 2:

The anti-vibration elements are positioned at interfaces between housing portions to cushion against vibrations before they can cause damage to mechanical and electrical components, enabling reliable operation in demanding conditions.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

3Ease of operation

If anti-vibration elements are added to reduce vibrations, then operator fatigue is reduced, but the device complexity increases

Engineering Contradiction:
Improveoperator fatigueVSAvoidstructure
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The anti-vibration elements are integrated into the existing housing structure at interfaces between housing portions, combining vibration reduction functionality with the structural design rather than adding separate vibration isolation systems.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The partition wall serving as a structural element also incorporates anti-vibration functionality through integrated elements and waterproof membranes, making it serve multiple purposes: structural support, vibration reduction, and environmental sealing.

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

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 solution significantly reduces operator fatigue by minimizing vibrations and noise, while protecting the wrench's mechanical and electrical components from environmental stressors, thereby extending its lifespan and ensuring reliable operation in challenging conditions.

Implementation Method 1

one or more first damper elements interposed between the transmission housing and the main housing... so that the vibrations transmitted from the transmission housing to the main housing are dampened by the first damper elements

Methodology Applied
Scientific EffectDamping: Damping

Implementation Method 2

one or more second damper elements interposed between the main housing and the handlebar structure... so that the vibrations transmitted from the main housing to the handlebar structure are dampened by the second damper elements

Methodology Applied
Scientific EffectDamping: Damping

Implementation Method 3

a cooling fan configured to be activated together with the operation of the motor, sucking ambient air through an inlet opening formed in the main housing, conveying the sucked ambient air through, or along, the motor and expelling the air through an outlet opening

Methodology Applied
Scientific EffectForced Convection: Forced Convection

Implementation Method 4

the motor is housed inside a special motor compartment of the main housing and at least one heat-sensitive part of the electronic control system... is housed inside a protected compartment... separated from the motor compartment by means of a separation wall which forms a metal radiator (heat sink) in relation of heat exchange with the heat-sensitive part

Methodology Applied
Scientific EffectHeat Sink: Heat Sink

Data Source

PatentEP4056325B1Impact wrench
Publication Date: 2025.01.29 CEMBRE SPA
  • EP4056325B1 patent drawingFigure 1~2
  • EP4056325B1 patent drawingFigure 3~5
  • EP4056325B1 patent drawingFigure 6~7

AI summary

An impact wrench (1) comprises a motor unit (3) with a motor (3') adapted to produce a rotary motion and an operating switch (5) for operating the motor (3'), a tool-holder shaft (2) rotatable about a rotation axis (R), a transmission unit (6) with a percussion mechanism (7), connected between the motor unit (3) and the tool-holder shaft (2), a handlebar structure (14) with two gripping handles (9, 10) for manually gripping the wrench (1), an electronic control system (27), containing at least one electronic control board, connected to one or more electric batteries (4) and to the operating switch (5), wherein the electric motor (3') is simultaneously powered by two rechargeable batteries (4), connected in parallel to each other and housed together in the main housing (15), wherein the electronic control system (27) comprises a device for generating the current supplied to the motor (3'), configured to utilize a first battery (4') of the batteries (4) for generating a first phase of a three-phase current, a second battery (4") of the batteries (4) for generating a second phase of the three-phase current, and both the first and second batteries (4', 4") for generating a third-phase of the three-phase current, wherein the ratio of the contributions of the first battery (4') and second battery (4") to the generation of the third phase is determined depending on the residual charge state of the batteries (4', 4"), wherein the least charged battery (4', 4") contributes less to the generation of the third phase than the most charged battery (4", 4').