Free-Piston Device Pressure Control via Piston Rod Channels

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing free-piston devices are complex and lack a modular design, requiring external valves for pressure control and high-pressure systems, which complicates their construction and operation.

Innovation Solution

A free-piston device with a piston receptacle that includes a side for a linearly movable active element, allowing mechanical energy to be extracted and coupled with applications, featuring a channel with openings that enable time-dependent pressure equalization between the admission pressure chamber and resilience space without external valves, and a compact design with minimized distance between expansion and resilience spaces.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If external valves are used for pressure control in free-piston devices, then pressure regulation is achieved, but device complexity increases

Engineering Contradiction:
Improvepressure controlVSAvoidconstruction complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The invention extracts the valve function from the traditional external valve system and integrates it into the piston rod itself through channels with openings. This removes the need for separate high-pressure valves while maintaining pressure control capability, directly resolving the contradiction between pressure regulation and device complexity.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The piston rod is given multiple functions: it serves as both the mechanical connector for energy transfer and as the pressure control element through its integrated channels and openings. This multi-functionality eliminates the need for separate valve components, reducing overall device complexity while maintaining reliable pressure control.

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

2Volume of moving object

If a compact design with minimized distance between expansion and resilience spaces is implemented, then device size is reduced, but manufacturing precision requirements increase

Engineering Contradiction:
Improvedevice sizeVSAvoidspacing precision
Core Design Contradiction:
Volume of moving objectVSManufacturing precision

Solution Approach 1:

The invention merges the expansion space and resilience space into a single integrated piston receptacle structure with minimized distance between them. The piston device acts as a separator within this unified structure, allowing compact design while the piston's physical presence provides natural spacing reference, reducing manufacturing precision requirements.

Inventive Principle:
Principle #5Merging (Combining)

3Adaptability or versatility

If the piston stroke is made variably adjustable, then adaptability is improved, but device complexity increases due to additional control mechanisms

Engineering Contradiction:
Improvepiston stroke adjustmentVSAvoidcontrol mechanism complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The invention uses feedback from the gas spring pressure and piston position to automatically adjust the piston stroke. The channels in the piston rod open or close based on piston position, creating a self-regulating system that provides variable stroke adjustment without complex external control mechanisms.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The piston rod with its position-dependent channels serves itself by using its own movement to control the pressure equalization. The system automatically adjusts its own operation based on piston position, eliminating the need for separate control mechanisms and reducing device complexity while maintaining adaptability.

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

This solution enables a modular, compact free-piston device with simplified construction and operation, allowing for efficient energy transfer and pressure control without the need for high-pressure valves, facilitating serial or parallel coupling of applications and minimizing length dimensions.

Implementation Method 1

If the resilience space is designed as a gas spring space, the gas pressure in the resilience space can be maintained by the blow-by or used to reduce the pressure loss in the resilience space.

Methodology Applied
Scientific EffectGas spring: Elasticity

Implementation Method 2

A free-piston device can be used, for example, to partially convert chemical energy via combustion into mechanical energy, namely kinetic energy of a piston device

Methodology Applied
Scientific EffectCombustion: Combustion

Implementation Method 3

this mechanical energy can then in turn be converted at least partially into electrical energy via a linear drive

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentEP2173988B8Free-piston device and method for controlling and/or regulating a free-piston device
Publication Date: 2018.07.25 UMC UNIVERSAL MOTOR CORP

AI summary

The invention relates to a free-piston device, comprising at least one piston chamber, at least one piston assembly linearly moving in the corresponding piston chamber, said piston having a first piston surface as well as a second piston surface facing away from the first piston surface. The piston chamber includes an expansion space delimited by the first piston surface. The piston device can be driven by the action of a medium expanding in the expansion space. A recovery space in the piston chamber or chambers is delimited by the second piston surface and is connected through fluid action with at least one precompression chamber.