Turbocharger Ejector Check Valve Preventing Fresh Air Leakage
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Solution Overview
Problem
In turbocharger engine systems, PCV systems face inefficiency due to unwanted fresh air leakage from the oil separator when the turbocharger is off, which prevents effective blowby ventilation and oil recycling.
Innovation Solution
A check valve with a moveable spool and spring mechanism that blocks the first inlet when the turbocharger is off, preventing fresh air from entering the oil separator, and allows PCV gas flow when the turbocharger is on, ensuring proper ventilation and oil recycling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the ejector is designed to allow free air flow from the first inlet when the turbocharger is off, then the device complexity is reduced, but fresh air leaks into the oil separator preventing effective blowby ventilation
Solution Approach 1:
The harmful element (unwanted fresh air) is extracted from the system by using the spool to block the first inlet passage when the turbocharger is off, preventing fresh air from entering the oil separator and compromising blowby ventilation efficiency
Solution Approach 2:
The spool is designed as a movable component that dynamically changes position based on system conditions - blocking the first inlet when the turbocharger is off and allowing air flow when the turbocharger is running, thereby maintaining reliable blowby ventilation across different operating states
2Reliability
If a check valve mechanism is added to prevent fresh air leakage, then blowby ventilation efficiency is improved, but the device complexity increases due to additional components
Solution Approach 1:
The check valve functionality is merged with the existing ejector structure by integrating the spool, nozzle, and spring mechanism into the ejector body, allowing the same component to serve both as an air extraction device and a check valve to prevent fresh air leakage
Solution Approach 2:
The spool serves multiple functions: it acts as a closure element to block the first inlet when needed, and its movement is controlled by the spring mechanism that also serves as a return mechanism, making the check valve system multi-functional and reducing overall device complexity
3Reliability
If the spool outer edge is made larger than the first inlet to ensure complete blocking, then fresh air prevention is improved, but the area of the spool increases requiring more material
Solution Approach 1:
The spool outer edge is designed with non-uniform dimensions - specifically larger than the first inlet at the critical blocking region to ensure complete sealing, while other portions of the spool maintain standard dimensions, thereby achieving reliable inlet sealing without unnecessarily increasing overall spool mass
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 check valve enhances the efficiency of the PCV system by preventing fresh air leakage and ensuring effective ventilation and oil recycling by controlling air flow through the spool's positions, thereby improving the overall performance of the turbocharger engine.
Implementation Method 1
The subassembly contained within the ejector connected to the ejector by means of a spring wherein the spring is operable to return the subassembly to a resting position when not in use
Implementation Method 2
The ejector creates a pressure drop for additional pull of PCV gas under boosted conditions of the turbocharger engine
Data Source
AI summary
PCV systems are well known in the art and commonly used in turbocharged engines. The ejector creates a pressure drop for additional pull of PCV gas under boosted conditions of the turbocharger engine. The ejector typically includes a first inlet and a second inlet and a sole outlet. The first inlet pulls air from the compressor of the PCV system. The second inlet pulls air from the cyclone separator of the PCV system. Air exiting the ejector is exited to the intake manifold. However, when the turbocharger of the system is off, fresh air can leak in from the inlet from the oil separator thereby preventing the ventilation of blowby. The unwanted air reduces the efficiency of the turbocharger system. Accordingly, an ejector preventing unwanted fresh air flow is needed in the art.