Idle Stop Control System Cabin Heat Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current idle stop technologies in vehicles are costly, consume excessive electrical power, and require additional weight and space, as they rely on auxiliary electric water pumps to maintain cabin heat, which is inefficient for short stops and can deplete the vehicle's battery charge.
Innovation Solution
An idle stop control system using an electronic control unit to determine when to idle stop and restart the engine, leveraging residual engine heat and the HVAC blower to maintain cabin comfort without an auxiliary water pump, optimizing engine operation based on cabin temperature saturation and ambient conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If an auxiliary electric water pump is added to maintain cabin heat during idle stop, then cabin comfort is maintained, but vehicle cost, weight, and packaging space increase
Solution Approach 1:
The patent removes the auxiliary electric water pump from the system entirely. Instead of adding a pump to maintain coolant circulation, the system relies on the vehicle's existing mechanical water pump that operates with the engine, and uses the HVAC blower fan to circulate air through the heater core using residual engine heat, thereby maintaining cabin comfort without the additional pump component.
Solution Approach 2:
The existing mechanical water pump serves dual purposes: it cools the engine when running and provides coolant circulation for heater core heat transfer during idle stop conditions. The HVAC blower fan also serves multiple functions including cabin air circulation and heat distribution through the heater core, eliminating the need for a dedicated auxiliary pump.
2Temperature
If an auxiliary electric water pump is used during idle stop, then cabin heat is maintained, but electrical load on the battery increases
Solution Approach 1:
The system converts the residual heat that would normally be wasted when the engine is turned off into a useful resource for maintaining cabin temperature. By circulating air through the heater core using the existing mechanical pump and blower fan, the system utilizes this residual thermal energy beneficially without requiring additional electrical power for pumping.
Solution Approach 2:
The system uses its own existing components (mechanical water pump driven by engine operation, HVAC blower fan) to maintain cabin heat during idle stop conditions, rather than requiring an externally powered auxiliary electric pump. The engine's own thermal energy and mechanical systems serve the dual purpose of cooling and heating.
3Temperature
If an electric water pump is used for extended periods, then cabin comfort is maintained, but battery charge is depleted and engine restart capability is limited
Solution Approach 1:
The system operates the HVAC blower fan and coolant circulation periodically based on sensor feedback regarding cabin temperature and engine operating conditions, rather than continuously running an electric pump. This periodic operation conserves battery charge while maintaining comfort when needed.
Solution Approach 2:
The system uses partial action by relying on residual engine heat and the existing mechanical pump's circulation capacity, which is more than sufficient for typical idle stop durations. This avoids the excessive electrical load that would result from running a high-capacity electric pump at full power continuously.
4Device complexity
If a conventional mechanical water pump is replaced with an electric pump, then no auxiliary pump is needed, but cost increases and performance exceeds requirements for average stop times
Solution Approach 1:
The system uses the existing mechanical water pump's circulation capacity, which provides more than sufficient flow for heater core heat transfer during typical idle stop conditions. This avoids the excessive cost of replacing the pump with an expensive electric model when the mechanical pump's existing capability is already adequate for the application.
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 approach maintains cabin comfort during engine idle stops without the need for supplemental pumps, reducing electrical load, conserving battery charge, and minimizing weight and space, while optimizing fuel efficiency and comfort based on ambient conditions.
Implementation Method 1
residual engine heat can be transported to the heater core, which warms air from the HVAC blower fan to maintain heat within the vehicle cabin
Data Source
AI summary
An idle stop control system and method for a vehicle includes at least one electronic control unit disposed within the vehicle that is configured to determine whether an idle stop condition for the vehicle is satisfied and whether the vehicle is in a stopped condition. The at least one electronic control unit is further configured to idle stop an engine of the vehicle when determined that both the idle stop condition is satisfied and that the vehicle is in the stopped condition. The at least one electronic control unit is also configured to determine whether an engine restart condition is satisfied after the engine is idle stopped and to restart the engine when determined that the engine restart condition is satisfied.