Vehicle Cooling Fan Motor Lock Control via Refrigerant Pressure

Solution Overview

Problem

Conventional methods for controlling vehicle cooling fans in severe cold conditions are complex and inaccurate, leading to potential motor damage and safety issues due to freezing, as they rely on ignition-off time rather than real-time refrigerant pressure changes.

Innovation Solution

An apparatus and method that utilize a state detector and controller to lock the fan motor based on the change rate of air conditioner refrigerant pressure, intake temperature, and vehicle speed, eliminating the need for separate components and improving accuracy by monitoring these conditions in real-time.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the fan motor is locked based on ignition-off time in winter, then the motor damage is prevented, but the control logic becomes too complex and accuracy is low

Engineering Contradiction:

Improvemotor damage preventionVSAvoidcontrol logic complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent changes the control parameter from ignition-off time to air conditioner refrigerant pressure. By monitoring refrigerant pressure changes rate, the system determines when to lock the fan motor, replacing complex time-based logic with a simpler pressure-based parameter that directly reflects freezing conditions.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent replaces the mechanical/time-based control system with a pressure-based detection system. By using refrigerant pressure as the control criterion, the system substitutes complex temporal logic with a more accurate and simpler physical parameter measurement.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Device complexity

If the fan motor is controlled according to ignition-off time, then the control is simplified, but the accuracy is low and driver dissatisfaction occurs

Engineering Contradiction:

Improvecontrol logic simplicityVSAvoidcontrol accuracy

Core Design Contradiction:

Device complexityVSMeasurement precision

Solution Approach 1:

The patent changes the control parameter from ignition-off time to air conditioner refrigerant pressure. By monitoring refrigerant pressure changes rate, the system determines when to lock the fan motor, replacing complex time-based logic with a simpler pressure-based parameter that directly reflects freezing conditions.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent implements feedback control by continuously monitoring refrigerant pressure and comparing it against threshold values. The system adjusts fan motor operation based on real-time pressure feedback, ensuring accurate response to actual freezing conditions rather than relying on predetermined time schedules.

Inventive Principle:

Principle #23Feedback

3Reliability

If the cooling fan is not operated in severe cold area, then the motor damage is prevented, but the air conditioner refrigerant pressure rises and motor damage or fire occurs

Engineering Contradiction:

Improvemotor damage preventionVSAvoidrefrigerant pressure buildup

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent implements feedback control by continuously monitoring refrigerant pressure and comparing it against threshold values. The system adjusts fan motor operation based on real-time pressure feedback, ensuring accurate response to actual freezing conditions rather than relying on predetermined time schedules.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The patent makes the fan motor control dynamic by continuously monitoring refrigerant pressure changes. Instead of a static control strategy, the system dynamically adjusts operation based on real-time pressure conditions, allowing the fan to operate when pressure indicates freezing while preventing operation when pressure is normal.

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS10538141B2Control apparatus and method for cooling fan of vehicle

Publication Date: 2020.01.21 HYUNDAI MOTOR CO LTD

AI summary

An apparatus for a vehicle includes a cooling fan installed in an engine compartment of the vehicle. A fan motor is connected with the cooling fan to drive the cooling fan. A state detector is configured to detect state data, and a controller is configured to control the cooling fan based on the state data when an intake temperature is within a predetermined range, to determine whether the state data satisfies a decision reference condition, and to lock the fan motor according to a change rate of air conditioner refrigerant pressure during a measurement time when the state data satisfies the decision reference condition.