Indoor Air Outlet Geometry for Longer AC Throw Without Short-Circuiting

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Solution Overview

Problem

The existing indoor units of air conditioning apparatuses face challenges in increasing the blow distance of conditioned air while preventing short-circuiting and minimizing the size of the lower surface, as conventional designs either struggle to reach far due to rectangular air outlet shapes or lead to increased size when attempting to improve reach by enlarging the width.

Innovation Solution

The indoor unit features an air outlet design with an edge bulging towards the air inlet, an airflow direction adjusting member that covers the outlet, and a steeper angle at the lengthwise end portions to guide airflow away from the ceiling, reducing short-circuiting and maintaining initial air speed.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of moving object

If the length in the width direction of the air outlet is increased to improve the blow distance of conditioned air, then the far reach of conditioned air is improved, but the size of the lower surface of the indoor unit increases

Engineering Contradiction:
Improveblow distance of conditioned airVSAvoidsize of lower surface of indoor unit
Core Design Contradiction:
Length of moving objectVSArea of stationary object

Solution Approach 1:

The air outlet is designed with a curved cross-sectional shape where the width in the width direction gradually increases from the air inlet side toward the air outlet side. This curved geometry allows the air outlet to maintain a compact overall size while providing an effectively larger outlet area for improved air blow distance, resolving the contradiction between far reach and lower surface size.

Inventive Principle:
Principle #14Spheroidality (Curvature)

2Length of moving object

If the shape of the air outlet is enlarged toward the air inlet side to improve blow distance, then the ability of conditioned air to have a far reach is improved, but short-circuiting occurs where conditioned air is blown out and soon sucked back in

Engineering Contradiction:
Improveblow distance of conditioned airVSAvoidshort-circuiting of conditioned air
Core Design Contradiction:
Length of moving objectVSObject-generated harmful factors

Solution Approach 1:

The curved cross-sectional shape of the air outlet, with width gradually increasing from inlet to outlet side, creates a more favorable pressure gradient and airflow pattern. This geometry reduces the likelihood of air flow reversal and short-circuiting while maintaining effective blow distance, as the gradual expansion promotes stable laminar flow rather than turbulent recirculation.

Inventive Principle:
Principle #14Spheroidality (Curvature)

3Length of moving object

If the air outlet shape is changed from a long rectangle to a shape with increased width direction length, then the far reach of conditioned air is improved, but the design complexity and manufacturing difficulty increase

Engineering Contradiction:
Improveblow distance of conditioned airVSAvoidmanufacturing of air outlet shape
Core Design Contradiction:
Length of moving objectVSEase of manufacture

Solution Approach 1:

The curved cross-sectional shape of the air outlet can be efficiently manufactured using standard molding or forming techniques. The gradual curvature from the air inlet side to the outlet side represents a simple continuous surface that is well-suited for conventional manufacturing processes, avoiding the need for complex multi-piece assemblies or difficult-to-form geometries.

Inventive Principle:
Principle #14Spheroidality (Curvature)

Data Source

PatentEP2498018B1Indoor unit of air conditioner
Publication Date: 2021.02.17 DAIKIN INDUSTRIES LTD
  • EP2498018B1 patent drawingFigure 1
  • EP2498018B1 patent drawingFigure 2
  • EP2498018B1 patent drawingFigure 3

AI summary

To provide an indoor unit of an air conditioning apparatus that can increase the blow distance of conditioned air blown out from an air outlet while suppressing short-circuiting and an increase in the size of the lower surface of the indoor unit. An indoor unit (4) of an air conditioning apparatus (1) is equipped with an indoor unit casing (31) and airflow direction adjusting portions (70). The indoor unit casing (31) has an air inlet (35) and long-side air outlets (51 to 54) whose edges on the air inlet (35) side bulge toward the air inlet (35) side. The airflow direction adjusting portions (70) cover at least parts of the long-side air outlets (51 to 54) and have shapes whose edges on the air inlet (35) side bulge toward the air inlet (35) side.