Sub-engine type transport refrigeration unit

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Solution Overview

Problem

Existing self-powered transportation refrigeration units face instability in air pressure and temperature due to external influences from transport ships or vehicles, leading to potential vibration and noise issues in the diesel engine.

Innovation Solution

A self-powered transportation refrigeration unit design featuring a sub-engine with an intake pipe open to a separate heat exchange room, which is partitioned from the engine room, ensuring stable air pressure and temperature, and incorporating a fan to draw outside air for cooling, while positioning the intake port to avoid mainstream airflow and foreign matter.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If air is introduced from outside the container refrigeration apparatus to the diesel engine, then the engine can operate, but the air pressure and temperature become unstable due to external influences from transport ships or vehicles

Engineering Contradiction:
Improveair supply stabilityVSAvoidexternal environmental influence
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The container refrigeration apparatus is divided into separate compartments: an engine room for the diesel engine and a heat exchange room for the condenser. The partition wall between these rooms creates isolated air environments, allowing the engine to draw air from a stable, enclosed space rather than directly from the fluctuating external environment.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The heat exchange room acts as an intermediary chamber between the external environment and the engine room. Air is first drawn into the heat exchange room, where its pressure and temperature are stabilized through the condensing operation, before being supplied to the engine. This intermediary space buffers external fluctuations.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Device complexity

If the intake port is positioned to draw air from outside, then air supply is simple, but foreign matter such as dust and debris may be introduced into the engine

Engineering Contradiction:
Improveair intake structureVSAvoidforeign matter contamination
Core Design Contradiction:
Device complexityVSObject-affected harmful factors

Solution Approach 1:

The air intake system is segmented into two distinct paths: one for the engine room and another for the heat exchange room. The engine room intake is positioned to draw air from within the container rather than from external openings, eliminating direct exposure to foreign matter while maintaining structural simplicity.

Inventive Principle:
Principle #1Segmentation

3Device complexity

If the engine room and heat exchange room are not separated, then the structure is simpler, but the engine is affected by waste heat causing temperature and pressure fluctuations in supplied air

Engineering Contradiction:
Improvestructural complexityVSAvoidair temperature stability
Core Design Contradiction:
Device complexityVSTemperature

Solution Approach 1:

The container refrigeration apparatus is divided into separate engine room and heat exchange room compartments with a partition wall between them. This segmentation isolates the engine from waste heat generated by the condenser operation, maintaining stable air temperature and pressure for engine combustion while adding minimal structural complexity.

Inventive Principle:
Principle #1Segmentation

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 configuration provides stable air supply to the sub-engine, reducing vibration and noise, enhancing maintainability, and preventing foreign matter introduction, thus improving operational stability and reducing noise emissions.

Implementation Method 1

an outdoor heat exchanger (8) which condenses gas compressed by the compressor (15)

Methodology Applied
Scientific EffectCondensation: Condensation

Implementation Method 2

an outdoor heat exchanger (8) which condenses gas compressed by the compressor (15)

Methodology Applied
Scientific EffectHeat transfer: Heat Exchanger

Implementation Method 3

the heat exchange room is separated from the space provided with the engine body by the partition wall, and the air in the heat exchange room has a stable pressure and a stable temperature

Methodology Applied
Scientific EffectThermal isolation: Thermal Insulation

Data Source

PatentEP3438442B1Sub-engine type transport refrigeration unit
Publication Date: 2019.12.11 MITSUBISHI HEAVY IND THERMAL SYST
  • EP3438442B1 patent drawingFigure 1~2
  • EP3438442B1 patent drawingFigure 3
  • EP3438442B1 patent drawingFigure 4

AI summary

The purpose of the present invention is to provide a transportation refrigeration unit in which air having stable pressure and stable temperature can be supplied to a sub-engine. A refrigeration unit (1) is provided with: a sub-engine (10) having a body part (11) and having an intake pipe (21) through which air is supplied to the body part (11); an outdoor heat exchanger (8) that condenses gas compressed by a compressor (15); and a casing (6) accommodating the sub-engine (10) and the outdoor heat exchanger (8). A partition wall (7) partitioning the casing (6) into an engine room (12) in which the body part (11) is set and a heat exchange room (9) in which the outdoor heat exchanger (8) is set, is provided in the casing (6). An intake port (25) of the intake pipe (21) through which air is supplied to the body part (11) is open to the heat exchange room (9) side.