Camshaft Phaser Rotor Vane Lobe Fluid Gap Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing camshaft phaser designs for internal combustion engines lack efficient mechanisms for adjusting the phase relationship between the crankshaft and camshaft, leading to suboptimal engine timing adjustments based on speed and other parameters.
Innovation Solution
A rotor and sprocket design with radially extending vanes and lobes that define pressure chambers, where the vanes and lobes have specific surface features to form fluid gaps and receiving surfaces, allowing for precise rotation and fluid pressure control between retard and advance positions, supported by a metal construction and sealing mechanisms to prevent leakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional camshaft phaser designs are used, then the structure is simpler, but the timing adjustment precision is insufficient
Solution Approach 1:
The rotor is segmented into multiple vanes that define separate pressure chambers, allowing independent fluid pressure control in different regions. This segmentation enables precise timing adjustment by controlling fluid flow to specific chambers, resolving the contradiction between precision and complexity through functional decomposition
Solution Approach 2:
The vanes and lobes incorporate specific surface features (gap surfaces, receiving surfaces, stop surfaces) at localized positions to control fluid gaps and pressure distribution. This local quality enhancement allows precise timing control without requiring complete redesign of the entire structure, balancing precision needs with overall simplicity
2Reliability
If vanes and lobes with specific surface features are implemented, then fluid pressure control is improved, but manufacturing complexity increases
Solution Approach 1:
The design incorporates curved recess sections in the vanes that receive corresponding lobes, creating smooth curved surfaces for reliable fluid gap formation. These curved features improve fluid pressure control reliability while being manufacturable through standard forming processes, reducing the manufacturing complexity penalty
3Adaptability or versatility
If the rotor rotates between retard and advance positions, then timing adjustment range is improved, but fluid leakage increases
Solution Approach 1:
The lobes of the sprocket act as intermediaries between the rotor vanes and the fluid pressure system. As the rotor rotates between retard and advance positions, the lobes maintain consistent fluid gaps with the vanes, preventing direct fluid leakage paths while allowing full timing adjustment range. This intermediary mechanism resolves the contradiction by providing both mobility and sealing
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
Enables precise adjustment of engine timing by creating defined pressure chambers that allow for smooth rotation and effective fluid pressure control, enhancing the engine's ability to optimize timing based on speed and other parameters.
Implementation Method 1
A first set of the plurality of lobes are substantially identical and each include opposite first and second sides and an end face surface remote from the ring body, a notched section that forms a notch in the inner surface of the ring body at each of the first and second sides, a narrowed end section remote from the ring body that forms a gap surface at each of the first and second sides, and a wing section between the notched section and the narrowed end section forms an outwardly extending wing at each of the first and second sides. The plurality of lobes of the sprocket are spaced to receive the plurality of vanes of the rotor, thereby defining retard and advance pressure chambers when the rotor rotates with respect to the sprocket between retard and advance positions.
Data Source
AI summary
A camshaft phaser that includes a rotor and a sprocket. A plurality of lobes of the sprocket are spaced to receive a plurality of vanes of the rotor, thereby defining retard and advance pressure chambers when the rotor rotates with respect to the sprocket between retard and advance positions. When the rotor rotates between the retard and advance positions, gap surfaces of the lobes cooperate with gap surfaces of the vanes to form fluid gaps therebetween, wings of the lobes fit into receiving surfaces of the vanes, and stop surfaces of the vanes abut the sides of the lobes.