Sealing Valve Control for Fuel Evaporative Emission
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional fuel evaporative emission control devices face issues with prolonged tank purge operations, which can lead to excessive power consumption and reduced durability of sealing valves, especially in vehicles with low engine operation frequencies like hybrid cars, where tank purge often requires engine startup and may not effectively reduce fuel tank pressure within a predetermined time.
Innovation Solution
A fuel evaporative emission control device that includes a tank pressure detection unit and a tank purge control unit to initiate tank purge by closing the canister opening/closing valve and opening the sealing valve when fuel tank pressure exceeds a predetermined level, and a tank purge restriction unit to stop tank purge by closing the sealing valve based on the operation state of the canister opening/closing valve, thereby restricting the operation time of the sealing valve and preventing prolonged opening.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stress or pressure
If tank purge is performed for a predetermined period of time to reduce fuel tank pressure, then the pressure inside the fuel tank is reduced, but the sealing valve is kept open for a long period of time which reduces durability and increases power consumption
Solution Approach 1:
The control unit continuously monitors fuel tank pressure and dynamically adjusts the sealing valve operation based on real-time pressure feedback. When pressure drops below the threshold, the control unit automatically closes the sealing valve, preventing prolonged operation and improving durability while maintaining effective pressure control.
2Stress or pressure
If tank purge is performed for a long period of time to effectively reduce fuel tank pressure, then pressure control is improved, but power consumption increases
Solution Approach 1:
Instead of continuous operation, the sealing valve is operated periodically based on pressure threshold monitoring. The valve opens only when pressure exceeds the threshold and closes when pressure drops below it, creating an on-demand periodic operation pattern that significantly reduces power consumption while maintaining effective pressure control.
3Object-generated harmful factors
If the engine is started to perform tank purge in hybrid vehicles with low engine operation frequency, then fuel evaporative gas can be treated, but fuel efficiency decreases due to prolonged engine operation
Solution Approach 1:
The system implements on-demand tank purge operation triggered only when fuel tank pressure exceeds the predetermined threshold. This periodic, event-driven approach minimizes engine startup frequency and operation duration, thereby improving fuel efficiency while still effectively treating fuel evaporative gas when necessary.
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 solution effectively restricts the operation of the sealing valve, suppressing long-term tank purge operations, reducing power consumption, and protecting the sealing valve from prolonged use, while also minimizing engine operation time and fuel consumption.
Implementation Method 1
causes the fuel evaporative gas inside the fuel tank to flow to the canister so as to cause the fuel evaporative gas to be absorbed by activated carbon placed inside the canister
Data Source
AI summary
A fuel evaporative emission control device including an electronic control unit that, when fuel tank inner pressure exceeds a first predetermined pressure, performs tank purge of closing a bypass valve and opening a sealing valve, discharging fuel evaporative gas inside the fuel tank into an air intake path of an engine in an operated state through a purge pipe and a vapor pipe, and treating the fuel evaporative gas, where, when tank purge is performed, if a first predetermined period of time passes after closing of the bypass valve without the fuel tank inner pressure falling to or below the first predetermined pressure, the sealing valve is closed and tank purge is stopped.