Gas Spring Fastening Tool Sealing for Dust and Pressure Retention

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing fastener driving tools with gas springs suffer from high leakage and wear due to inadequate sealing, leading to pressure and energy loss, resulting in a short service life and inconsistent performance.

Innovation Solution

The integration of a deformable dirt seal and energy transfer system with gas springs, including a roller holder and energy storage device, reduces leakage and maintains constant pressure, enhancing the speed and efficiency of energy transfer while extending the tool's service life.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional seals and gas spring cylinder running surfaces are used, then the device structure is simple, but leakage increases and service life decreases due to wear from dirt and environmental particles

Engineering Contradiction:
Improveservice lifeVSAvoidsealing system complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

A deformable dirt seal is introduced as an intermediary element between the gas spring piston and the external environment. This dirt seal deforms to accommodate the piston movement while maintaining a sealing barrier that prevents dirt and environmental particles from entering the gas spring cylinder, thereby protecting the running surfaces and extending service life without requiring complex additional sealing mechanisms

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The sealing approach transitions from rigid seals to a deformable dirt seal that changes its physical state and configuration based on operational conditions. The deformable nature of the seal allows it to adapt to piston movement and maintain effective sealing under varying pressure and contamination conditions, improving reliability without increasing structural complexity

Inventive Principle:
Principle #35Parameter changes

2Power

If high setting energy is achieved through faster piston speed, then driving performance improves, but leakage increases disproportionately due to seal inability to follow surface roughness

Engineering Contradiction:
Improvesetting energyVSAvoidgas spring leakage
Core Design Contradiction:
PowerVSLoss of energy

Solution Approach 1:

The deformable dirt seal serves as a protective intermediary that isolates the gas spring cylinder running surfaces from direct contact with dirt and environmental particles. This protection maintains surface integrity even at high piston speeds, preventing the leakage that would otherwise occur when seals cannot adequately follow rough surfaces during rapid motion

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The dirt seal provides beforehand protection by preventing contamination of the gas spring cylinder running surfaces before high-speed operation can cause leakage. This preventive sealing approach ensures that even when the piston moves rapidly, the protected surfaces maintain adequate sealing contact, reducing leakage at high setting energies

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

3Device complexity

If the gas spring piston directly accelerates the fastener, then the energy transfer system is simple, but dust ingress causes high wear and pressure loss

Engineering Contradiction:
Improveenergy transfer system complexityVSAvoidpressure retention
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The deformable dirt seal acts as an intermediary protective barrier between the external environment and the gas spring system. It prevents dust and environmental particles from entering the cylinder, thereby protecting the running surfaces and maintaining pressure retention without complicating the direct energy transfer mechanism from gas spring piston to fastener

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The deformable dirt seal provides self-protecting functionality by automatically deforming to seal against contamination sources. This self-service sealing action protects the gas spring system from wear and pressure loss without requiring external maintenance or complex additional protective mechanisms

Inventive Principle:
Principle #25Self-service

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 achieves higher setting energy and extended service life by minimizing dust ingress, reducing wear, and maintaining consistent pressure, resulting in improved fastening quality and durability.

Implementation Method 1

a gas spring with a gas spring cylinder and a gas spring piston... a gas arranged in the closed partial volume of the first cylindrical container forms a first gas spring

Methodology Applied
Scientific EffectGas spring: Compression

Implementation Method 2

the seals and gas spring cylinder running surfaces are not robust enough against dirt and/or environmental particles... The deformable dirt seal encloses a variable volume between the gas spring and the roller holder

Methodology Applied
Scientific EffectPhysical barrier sealing: Physical Containment

Data Source

PatentEP4667160A1Tool with gas springs and dust protection system
Publication Date: 2025.12.24 HILTI AG
  • EP4667160A1 patent drawingFigure 1a~1b
  • EP4667160A1 patent drawingFigure 2a~2b
  • EP4667160A1 patent drawingFigure 3a~3b

AI summary

Working device for driving a fastening element into a substrate, comprising an energy transfer system, wherein the energy transfer system comprises a compression element, a roller holder, an energy transfer belt, an energy transfer element and an energy storage device for storing mechanical energy, wherein the energy storage device is a gas spring with a gas spring cylinder and a gas spring piston, wherein the energy transfer system comprises a deformable dirt seal, wherein the deformable dirt seal encloses a variable volume between the gas spring and the roller holder.