Fan and indoor machine of air conditioning device provided with fan

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing air-conditioning apparatus indoor unit installation design makes it difficult for workers to efficiently attach and detach the fan from the motor, particularly when installed on a ceiling, and there is a risk of losing small washers during maintenance.

Innovation Solution

A fan design that incorporates a washer with a flat plate-shaped metal bearing surface and an insulating outer peripheral portion, which is integrated with fitting portions on the boss part, allowing easy handling and preventing loss, while ensuring the washer is not rotated relative to the rotating shaft.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a small washer is used between the nut and boss end surface, then the fan can be fastened to the motor, but the washer is easily lost during inspection and maintenance

Engineering Contradiction:
Improvefan attachmentVSAvoidwasher retention
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The washer is divided into two distinct portions: a washer bearing surface portion made of metal for fastening function, and a washer outer peripheral portion made of insulating material for retention function. This segmentation allows each portion to serve its specific purpose optimally, preventing loss while maintaining attachment capability.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The washer is constructed as a composite structure integrating metal and insulating materials. The metal bearing surface portion provides the necessary mechanical strength for fastening, while the insulating outer peripheral portion prevents electrical conductivity and reduces loss risk. This composite approach resolves the contradiction between fastening reliability and component retention.

Inventive Principle:
Principle #40Composite materials

2Ease of operation

If the worker fastens the nut while facing the ceiling surface, then the fan can be attached to the motor, but the task is difficult and efficiency is reduced

Engineering Contradiction:
Improvemaintenance accessibilityVSAvoidmaintenance efficiency
Core Design Contradiction:
Ease of operationVSProductivity

Solution Approach 1:

The washer outer peripheral portion is designed to protrude beyond the boss part, creating a self-gripping feature that allows the washer to be easily held and manipulated during attachment and detachment operations. This self-service design enables workers to perform maintenance tasks more efficiently without requiring additional tools or complex procedures.

Inventive Principle:
Principle #25Self-service

3Strength

If the washer bearing surface portion is made of metal, then fastening strength is improved, but electrical conductivity creates safety concerns

Engineering Contradiction:
Improvefastening strengthVSAvoidelectrical conductivity
Core Design Contradiction:
StrengthVSObject-affected harmful factors

Solution Approach 1:

Different portions of the washer have different material properties: the bearing surface portion is made of metal for high strength fastening, while the outer peripheral portion is made of insulating material to eliminate electrical conductivity hazards. This local quality differentiation allows the single component to simultaneously satisfy both mechanical strength requirements and electrical safety requirements.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP3462038B1Fan and indoor machine of air conditioning device provided with fan
Publication Date: 2020.07.08 MITSUBISHI ELECTRIC CORP
  • EP3462038B1 patent drawingFigure 1~2
  • EP3462038B1 patent drawingFigure 3~4
  • EP3462038B1 patent drawingFigure 5~6

AI summary

A fan according to the invention is a fan including a motor, a rotating shaft for transmitting rotation of the motor, and a boss part through which the rotating shaft is inserted at a rotation center. A distal end portion of the rotating shaft protrudes from the boss part, the distal end portion is inserted through a center hole of a washer, and is screwed with a fastening part, and the washer includes a washer bearing surface portion that is fastened by being sandwiched between the fastening part and an end surface of the boss part, and a washer outer peripheral portion surrounding an outer periphery of the washer bearing surface portion. The washer bearing surface portion and the washer outer peripheral portion are integrated with each other.