Multifunction Valve Cooling Control for Idle Stop-Start Engines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The controllability of cooling apparatuses for internal combustion engines deteriorates during short-time engine stopping and restarting due to the time required for the cooling water circulation system to reach an intended state, affecting engine performance and fuel efficiency.
Innovation Solution
A cooling apparatus with a multifunction valve and electronic control unit (ECU) that adjusts coolant circulation and valve operations based on temperature, allowing for continuous coolant circulation and targeted heat exchange during engine stopping and restarting, thereby reducing the deterioration in controllability and improving fuel efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the valve is actuated to a closed position upon automatic engine stopping, then the engine can be stopped for fuel efficiency, but the controllability of the cooling apparatus deteriorates during restart due to time required for cooling water to reach intended state
Solution Approach 1:
The control apparatus performs preliminary actions by maintaining valve positions and coolant circulation states during automatic engine stopping. The first valve keeps the coolant circulation channel open and the second valve maintains heat exchanger connections, so when the engine restarts, the cooling system is already in the intended state without requiring transition time, thus preserving controllability while enabling fuel-efficient stopping
Solution Approach 2:
The cooling water circulation and valve operations continue uninterrupted during automatic engine stopping. The pump maintains coolant flow through the engine and heat exchangers, and valves remain in positions that sustain thermal management functions, ensuring continuous useful action that prevents controllability deterioration upon restart
2Productivity
If the valve is returned to original position upon engine restart, then the system can resume normal operation, but time is required for cooling water temperature state to stabilize, affecting responsiveness
Solution Approach 1:
During the engine stopping period, the control apparatus maintains valves in positions that preserve the cooling water temperature distribution and circulation patterns. This preliminary maintenance of system state means that upon restart, no time is lost for the cooling water to reach its intended temperature state, as it was already maintained in that state throughout the stopping period
Solution Approach 2:
The control apparatus monitors cooling water temperature parameters and adjusts valve positions and pump operations to maintain optimal temperature distribution during engine stopping. By actively managing temperature parameters rather than allowing passive cooling, the system achieves rapid responsiveness upon restart without time loss
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
The solution effectively reduces the time required to reach target coolant temperatures during engine restarts, enhancing the controllability and fuel efficiency of the cooling apparatus, especially during idling stop-and-start control operations.
Implementation Method 1
a first valve that opens/closes a first communication portion that communicates between the engine cooling water circulation circuit and the heat exchanger, and a second valve that opens/closes a second communication portion that communicates between the heat exchanger and the heat accumulator
Implementation Method 2
a heat accumulator for storing/circulating engine cooling water in an engine cooling water circulation circuit that connects an engine and a heater core of an air-conditioning unit
Implementation Method 3
high-temperature engine cooling water is thermally insulated and stored inside the heat accumulator
Implementation Method 4
since a valve operation that is in accordance with the temperature of a coolant is performed during automatic stopping of an internal combustion engine, a deterioration in the controllability of the cooling apparatus when restarting the internal combustion engine after automatic stopping can be reduced or even suppressed
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A cooling apparatus includes a coolant circulation channel for returning a coolant that passes through an engine main body (10), after causing the coolant to exchange heat with a radiator (20), device(s) (22) and a heater (24), respectively. A multifunction valve (18) as a rotary valve that is capable of adjusting the amount of coolant that is circulated to the radiator (20), device(s) (22) and heater (24), respectively, is disposed in the coolant circulation channel. When automatic stopping of the engine is performed by idle stop-start control or the like, during the automatic stopping the control apparatus continues to execute the valve control of the multifunction valve (18) that is being executed during the operation before the start of the automatic stopping.