Internal Combustion Engine Starterless Start via Crank Angle Positioning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Modern internal combustion engines face challenges in achieving reproducible starting operations, leading to variations in fuel filling, pressure, and residual gas content, resulting in acoustic and oscillation differences during engine restarts.
Innovation Solution
The method involves using an electric motor to drive the crankshaft of a deactivated internal combustion engine, moving a piston to introduce a predetermined quantity of working gas into the starting cylinder, creating reproducible combustion conditions by setting a specific crank angle position, and controlling gas exchange valves for optimized filling and scavenging, allowing for starterless or low-starter-power engine starts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a sufficient quantity of fresh air is guided into the starting cylinder during engine rundown, then the reliability of direct start is improved, but the reproducibility of starting operations deteriorates due to variations in filling quantity, pressure, and residual gas content
Solution Approach 1:
The patent applies preliminary action by pre-rotating the crankshaft to a specific crank angle position (e.g., 60° before top dead center) before the actual starting process. This preliminary positioning of the piston ensures that the starting cylinder is in a predetermined state, allowing for reproducible filling conditions and consistent combustion parameters across multiple starting operations.
Solution Approach 2:
The patent changes the parameter of crankshaft rotational speed and position by rotating the crankshaft to a specific crank angle position before starting. This parameter change ensures that the piston is at a predetermined position, which standardizes the filling process and improves the reproducibility of starting operations while maintaining reliable direct start capability.
2Manufacturing precision
If the crankshaft is driven by an electric motor to move the piston for introducing working gas, then the reproducibility of combustion conditions is improved, but the device complexity increases
Solution Approach 1:
The patent applies universality by using the electric motor that is already part of the stop-start system for a dual purpose: both for starting the engine and for pre-rotating the crankshaft to the predetermined position. This multi-functional use of the existing electric motor improves combustion condition reproducibility without significantly increasing device complexity, as no additional motor is required.
3Object-generated harmful factors
If the piston is moved by driving the crankshaft with an electric motor, then acoustic and oscillation differences during starting operations are reduced, but the use of energy increases
Solution Approach 1:
The patent applies partial action by rotating the crankshaft only to a specific crank angle position (e.g., 60° before top dead center) rather than completing full rotation cycles. This partial rotation is sufficient to achieve the predetermined piston position for reproducible filling, thereby reducing acoustic and oscillation differences while minimizing the energy consumption of the electric motor compared to full starting cycles.
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 ensures reproducible and optimized starting operations with reduced noise and friction, minimizing acoustic and oscillation differences, and enabling energy-saving vehicle operation by maintaining controlled filling and scavenging of the starting cylinder.
Implementation Method 1
a crankshaft of the internal combustion engine is driven by an electric motor
Implementation Method 2
a piston, which is coupled to the crankshaft and is assigned to the cylinder which is fired first, is moved in order to introduce the predetermined quantity of working gas
Implementation Method 3
an ignition of a mixture, which comprises the predetermined quantity of working gas and a predetermined quantity of fuel, is effected within the cylinder
Data Source
AI summary
A method for starting an internal combustion engine and a motor vehicle are provided. The internal combustion engine includes a plurality of cylinders. To start the internal combustion engine while deactivated, a predefined amount of working gas is introduced into the cylinder that fires first. A crankshaft of the internal combustion engine is driven by an electric motor and by the movement of a piston coupled to the crankshaft and associated with the cylinder that fires first to introduce the predefined amount of working gas. Subsequently, the internal combustion engine is started by the ignition of a mixture including the predefined amount of working gas and a predefined amount of fuel inside the cylinder that fires first.