Heat-Shielded Piston Assembly for Linear Machine Thermal Isolation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing linear electric machines face challenges in minimizing heat transfer from the expansion chamber to the compression chamber, which affects efficiency and performance.

Innovation Solution

A piston assembly with a heat shield configuration is used to thermally isolate the expansion chamber from the compression chamber, utilizing materials like titanium and stainless steel to reduce heat conduction and radiation, and incorporating cavities to create thermal gaps, thereby minimizing heat transfer.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If a traditional piston design is used without heat shields, then the structure is simple and manufacturing is easier, but heat transfer from the expansion chamber to the compression chamber increases, reducing efficiency

Engineering Contradiction:

Improveheat transfer lossVSAvoidpiston structure complexity

Core Design Contradiction:

Loss of energyVSDevice complexity

Solution Approach 1:

Heat shields are introduced as intermediary components between the expansion chamber and compression chamber. These heat shields act as thermal barriers that intercept and block heat transfer paths, reducing thermal energy loss from the hot expansion chamber to the cold compression chamber without requiring a complete redesign of the piston structure

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The piston structure is segmented into multiple functional zones including heat shield sections, thermal barrier sections, and conductive sections. This segmentation allows different portions of the piston to perform different thermal functions, with heat shields providing thermal isolation while maintaining structural integrity and enabling controlled heat transfer where needed

Inventive Principle:

Principle #1Segmentation

2Productivity

If heat shields are added to the piston assembly, then heat transfer is reduced and efficiency improves, but manufacturing complexity and production time increase

Engineering Contradiction:

Improvepower generation efficiencyVSAvoidpiston assembly manufacturing

Core Design Contradiction:

ProductivityVSEase of manufacture

Solution Approach 1:

The heat shields are designed to nest within the piston assembly structure, with heat shield sections positioned within cavities or recesses of the piston body. This nesting approach allows the heat shields to be integrated into the existing piston manufacturing process without requiring separate assembly steps, thereby maintaining ease of manufacture while achieving improved thermal isolation

Inventive Principle:

Principle #7Nested doll (Nesting)

3Temperature

If thermal isolation is enhanced between chambers, then temperature differential is maintained for optimal performance, but heat dissipation from the expansion chamber may be insufficient

Engineering Contradiction:

Improvetemperature differential between chambersVSAvoidheat dissipation efficiency

Core Design Contradiction:

TemperatureVSLoss of energy

Solution Approach 1:

The piston assembly incorporates regions with different thermal properties: heat shield sections with low thermal conductivity for thermal isolation, and thermal barrier sections with specific heat capacity for heat absorption and dissipation. This local differentiation of thermal properties allows the piston to simultaneously maintain temperature differential between chambers and enable controlled heat dissipation from the expansion chamber

Inventive Principle:

Principle #3Local quality

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 effectively reduces heat transfer between the chambers, enhancing the efficiency and power density of the linear electric machine by maintaining a temperature differential for optimal piston movement and power generation.

Implementation Method 1

the piston body comprises at least one heat shield configured to reduce heat transfer between the expansion chamber and the compression chamber

Methodology Applied

Scientific EffectThermal insulation: Thermal Insulation

Implementation Method 2

utilizing materials like titanium and stainless steel to reduce heat conduction and radiation

Methodology Applied

Scientific EffectHeat conduction reduction: Conduction (thermal)

Implementation Method 3

utilizing materials like titanium and stainless steel to reduce heat conduction and radiation

Methodology Applied

Scientific EffectThermal radiation reduction: Thermal Radiation

Data Source

PatentUS20260018969A1Piston assembly for a linear electric machine

Publication Date: 2026.01.15 HYLIION HOLDINGS CORP

AI summary

A linear electric machine includes a shaft and a piston assembly operably coupled with the shaft. The piston assembly includes a piston housing; and a piston arranged in the piston housing and partially defining each of an expansion chamber and a compression chamber within the piston housing. The piston includes a first portion in thermal contact with the compression chamber, a second portion in thermal contact with the expansion chamber, and a piston body extending from the first portion to the second portion. The piston body includes at least one heat shield configured to reduce heat transfer between the expansion chamber and the compression chamber. The at least one heat shield extends from an upper portion of the piston body to a lower portion of the piston body.