Transmission Path Discharge Switching in Air Conditioner Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional air conditioners experience increased power consumption and heat dissipation issues due to discharging resistors used to clear residual charges in the transmission path, which can lead to inaccurate room temperature sensing.

Innovation Solution

An air conditioner design that incorporates a discharging resistor and a switching element controlled by a unit to connect or disconnect the resistor based on signal voltage levels, preventing current flow through the resistor during signal transmission, and using bidirectional switching elements and Zener diodes to protect components from surge voltage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If discharging resistors are connected between the two lines to forcibly discharge residual charges, then signal transmission reliability is improved, but power consumption increases due to continuous current flow through the resistors

Engineering Contradiction:
Improvesignal transmission reliabilityVSAvoidpower consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent applies the dynamics principle by making the discharging resistor connection state changeable rather than fixed. A switching element is introduced to dynamically connect or disconnect the discharging resistors based on the signal transmission state. During signal transmission, the switching element disconnects the discharging resistors to save power, while during idle periods, it connects them to maintain signal reliability by discharging residual charges.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent implements periodic action by controlling the switching element to periodically connect and disconnect the discharging resistors according to the signal transmission timing. The switching element is turned off during signal transmission periods and turned on during idle periods, creating a periodic on-off pattern that balances power consumption with signal reliability requirements.

Inventive Principle:
Principle #19Periodic action

2Measurement precision

If discharging resistors are continuously connected to discharge residual charges, then signal transmission accuracy is improved, but heat dissipation increases causing temperature rise in the remote controller housing

Engineering Contradiction:
Improvesignal transmission accuracyVSAvoidremote controller housing temperature
Core Design Contradiction:
Measurement precisionVSTemperature

Solution Approach 1:

The patent uses the dynamics principle to make the discharging resistor connection state changeable. The switching element dynamically controls the connection of discharging resistors, disconnecting them during signal transmission to reduce heat generation, and connecting them during idle periods to maintain signal accuracy by discharging residual charges.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent applies periodic action by implementing periodic connection and disconnection of the discharging resistors. The switching element creates a periodic pattern where resistors are disconnected during signal transmission (reducing heat) and connected during idle periods (maintaining signal accuracy), thus periodically managing heat dissipation.

Inventive Principle:
Principle #19Periodic action

3Reliability

If current flows through discharging resistors during signal transmission, then residual charges are discharged, but voltage drop occurs reducing transmission voltage

Engineering Contradiction:
Improvecharge discharge effectivenessVSAvoidtransmission voltage
Core Design Contradiction:
ReliabilityVSPower

Solution Approach 1:

The patent implements dynamics by making the discharging resistor connection state changeable through a switching element. During signal transmission, the switching element disconnects the discharging resistors to prevent voltage drop and maintain transmission voltage. During idle periods, the switching element connects the resistors to effectively discharge residual charges, thus dynamically balancing charge discharge effectiveness with voltage maintenance.

Inventive Principle:
Principle #15Dynamics

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 design reduces power consumption and heat generation, ensuring accurate room temperature sensing by minimizing current flow through discharging resistors and protecting components from voltage surges.

Implementation Method 1

a discharging resistor R5 and a discharging resistor R6, and an analog switch S1. One end of the discharging resistor R5 is connected to one line P1 of the transmission path 4

Methodology Applied
Scientific EffectElectrical Resistance: Electrical Resistance

Implementation Method 2

cathodes of Zener diodes D1 and D2 are respectively connected to the two lines P1 and P2, and the switching element S1 is structured with a CMOS circuit

Methodology Applied
Scientific EffectZener breakdown: Diode

Data Source

PatentEP2555480B1Air conditioning machine
Publication Date: 2018.08.08 DAIKIN INDUSTRIES LTD
  • EP2555480B1 patent drawingFigure 1
  • EP2555480B1 patent drawingFigure 2
  • EP2555480B1 patent drawingFigure 3

AI summary

Provided is an air conditioner that suppresses power consumption by discharging resistors for discharging residual charges of a transmission path. An analog switch is previously interposed between two discharging resistors R5 and R6. In sending an AMI signal to two lines (P1, P2) of a transmission path 4, an MCU 30 executes discharge control to cause the analog switch S1 to achieve an OFF state when a high level signal voltage is output, and to cause the analog switch S1 to achieve an ON state when a low level signal voltage is output.