Refrigeration device

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Refrigerating apparatuses performing vapor compression refrigeration cycles face significant pressure pulsation issues due to the restricted space within expanders, limiting the effectiveness of existing pressure-absorbing mechanisms.

Innovation Solution

A pulsation absorbing device is mounted on the refrigerant pipes connecting the compressor, expander, and other components, allowing for a larger size and increased volume to effectively absorb pressure variations by utilizing a piston that shifts between two chambers with a throttling mechanism to balance pressure.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If the pressure absorbing mechanism is mounted inside the expander, then the structure is compact, but the space for accommodating the pressure absorbing mechanism cannot be sufficiently secured

Engineering Contradiction:
Improvevolume of pressure absorbing mechanismVSAvoidstructural complexity of expander
Core Design Contradiction:
Volume of moving objectVSDevice complexity

Solution Approach 1:

The pressure absorbing mechanism is separated from the expander and mounted on the refrigerant pipe externally. This segmentation allows the pressure absorbing mechanism to have sufficient volume without complicating the internal structure of the expander, as the two components are now independent but functionally connected through the refrigerant circuit.

Inventive Principle:
Principle #1Segmentation

2Reliability

If the volume of the cylinder chamber is increased to effectively absorb pressure, then the pressure pulsation reduction is improved, but the space requirement inside the expander increases

Engineering Contradiction:
Improvepressure pulsation reduction effectivenessVSAvoidspace inside expander
Core Design Contradiction:
ReliabilityVSVolume of stationary object

Solution Approach 1:

The pressure absorbing mechanism is extracted from the expander and relocated to the refrigerant pipe. This extraction allows the cylinder chamber to have a larger volume for effective pressure pulsation absorption without consuming space inside the expander, as the mechanism now occupies external space on the refrigerant pipe.

Inventive Principle:
Principle #2Taking out (Extraction)

3Volume of moving object

If the pressure absorbing mechanism is mounted on the refrigerant pipe, then the space for accommodation is sufficient, but the device complexity increases

Engineering Contradiction:
Improvevolume of pressure absorbing mechanismVSAvoidoverall system complexity
Core Design Contradiction:
Volume of moving objectVSDevice complexity

Solution Approach 1:

The refrigerant pipe serves multiple functions: it transports refrigerant between components and also serves as the mounting structure for the pressure absorbing mechanism. This multi-functionality reduces overall system complexity by utilizing existing structural elements rather than adding completely new support structures.

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

4Reliability

If a piston is used to change the volume of the cylinder chamber, then the pressure pulsation is reduced, but the device complexity increases

Engineering Contradiction:
Improvepressure variation reductionVSAvoidmechanism complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The piston is directly driven by the pressure differential across the diaphragm, eliminating the need for external actuators, sensors, or control systems. The pressure-absorbing mechanism is self-regulating, automatically adjusting the cylinder chamber volume in response to pressure pulsations without external intervention, thereby reducing mechanism complexity.

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 significantly reduces pressure pulsation in the refrigerant, enhances piston responsiveness, and facilitates maintenance, while minimizing heat exchange and potential heat loss in the refrigerant circuit.

Implementation Method 1

When the pressure of the refrigerant flowing in the refrigerant pipe increases, the piston shifts toward the second chamber to increase the volume of the first chamber. This reduces each pressure in the first chamber and the refrigerant pipe communicating with the first chamber through the first connection pipe to suppress the pressure increase of the refrigerant.

Methodology Applied
Scientific EffectPressure variation: Pressure Gradient

Implementation Method 2

the second connection pipe and the first connection pipe are connected to a refrigerant pipe at the same refrigerant pressure. the second connection pipe includes a throttling mechanism

Methodology Applied
Scientific EffectThrottling: Pressure Drop

Data Source

PatentEP2048456B1Refrigeration device
Publication Date: 2017.08.30 DAIKIN INDUSTRIES LTD
  • EP2048456B1 patent drawingFigure 1
  • EP2048456B1 patent drawingFigure 2A~2C
  • EP2048456B1 patent drawingFigure 3~4

AI summary

In a refrigerant circuit (10) of a refrigerating apparatus (1), a pulsation absorbing device (30) is provided. In the pulsation absorbing device (30), a piston (32) is accommodated in a cylinder member (31) to divide its cylinder chamber into a pressure buffering chamber (33) and a back pressure chamber (34). The pressure buffering chamber (33) is connected to a second high-pressure refrigerant pipe (12) on the inflow side of an expander (22) through a first connection pipe (35). The back pressure chamber (34) is connected to a first high-pressure refrigerant pipe (11) on the discharge side of a compressor (20) through a second connection pipe (36) and a capillary tube (37).