Pneumatic Hybrid Engine With Fixed Camshafts And Charge Valves
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Internal combustion engines face inefficiencies at part-load conditions and high emissions during cold starts, with existing hybrid propulsion systems being complex and costly, and conventional engines struggling with turbo-lag and emissions due to cold catalytic converters.
Innovation Solution
A pneumatic hybrid internal combustion engine with a simplified setup using a first pressure vessel for compressed air and a second for hot exhaust, controlled by fast switching charge valves, allowing for various operation modes like conventional thermal, supercharged thermal, pneumatic pump, and pneumatic motor modes, which reduce fuel consumption and emissions by utilizing stored energy and avoiding complex valve actuation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If fully variable valve actuation is used for inlet and exhaust valves to enable pneumatic modes, then the engine can operate in pneumatic mode, but the construction becomes very expensive and unreliable
Solution Approach 1:
The valve system is segmented into two distinct types: inlet/exhaust valves with fixed camshaft actuation for reliability and simplicity, and charge valves with variable actuation for pneumatic mode control. This segmentation allows the system to achieve pneumatic functionality without requiring full variable actuation across all valves.
Solution Approach 2:
The charge valves are designed to perform multiple functions: controlling compressed air intake from the storage vessel, managing exhaust gas flow, and enabling transitions between thermal and pneumatic modes. This multi-functionality reduces the need for separate dedicated components.
2Device complexity
If fixed camshafts are used for inlet and exhaust valves, then the construction is simpler and more reliable, but the engine cannot operate in pneumatic mode without additional complex mechanisms
Solution Approach 1:
Charge valves serve as intermediary components that enable pneumatic mode operation without requiring modification of the fixed camshaft actuated inlet and exhaust valves. These charge valves mediate between the compressed air storage vessel and the combustion chamber, allowing pneumatic functionality to be added to a traditionally simple valve system.
3Adaptability or versatility
If variable actuation is used for all valves to enable two-stroke pneumatic operation, then pneumatic modes can be achieved, but the system becomes far away from production facility and proved technology
Solution Approach 1:
The system implements dynamic operation modes where the same physical hardware (fixed camshafts plus variable charge valves) can operate in different modes: conventional four-stroke thermal mode using only inlet/exhaust valves, or pneumatic mode utilizing charge valves to introduce compressed air. This dynamic reconfigurability allows production-ready components to achieve multiple functions.
4Adaptability or versatility
If complex variable valve mechanisms are used, then pneumatic modes are enabled, but the system requires three adjustable cam shafts which increases complexity
Solution Approach 1:
Instead of making all valves variable with complex camshaft mechanisms, the invention inverts the approach: inlet and exhaust valves remain fixed and simple, while charge valves are made variable to provide the necessary timing flexibility for pneumatic mode. This inversion places the complexity only where it is absolutely 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
The solution achieves up to 30% fuel savings, reduced emissions, and improved driveability with a cost-effective design, avoiding the need for fully variable intake and exhaust valves, and effectively managing cold start emissions by using pneumatic modes to heat the catalyst.
Implementation Method 1
a first pressure vessel suitable to receive and store compressed air from a combustion chamber
Implementation Method 2
a second pressure vessel suitable to receive and store compressed hot exhaust from a combustion cycle
Implementation Method 3
The gas-exchange is controlled via a fast (variably) switching charge valve arranged close by or inside the combustion chamber
Data Source
AI summary
The present disclosure relates to an pneumatic hybrid internal combustion engine with at least one combustion chamber composed of a cylinder in which a piston is arranged mechanically interconnected to a crank shaft via a piston rod. An inlet valve and an exhaust valve are both mechanically interconnected via a valve gear to the crank shaft. The engine further includes at least one charge valve which is actuated by a charge valve actuator in a fully variable manner such that the engine can be operated in a four stroke hybrid mode.