Sliding Cam Valve Drive Actuator with Intermediary Piece
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In multi-stage valve drives for internal combustion engines, significant surface pressures occur between the actuator and sliding cam, necessitating wide and heavy sliding cams to meet system tolerances, which further increases surface pressures.
Innovation Solution
A valve drive design that uses a sliding piece between the sliding cam and actuator, allowing for axial sliding with a single pin actuator, reducing system tolerances and surface pressures, and enabling incremental movement of the sliding cam in two axial directions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple pins and multiple grooves are used in the actuator and sliding cam, then the valve drive can achieve multi-stage adjustment, but considerable surface pressures occur between the actuator and sliding cam
Solution Approach 1:
A sliding piece is introduced as an intermediary component between the actuator pin and the sliding cam groove. The pin engages with the sliding piece, which in turn engages with the groove in the sliding cam. This intermediate element distributes the contact forces over larger surface areas, thereby reducing the surface pressure between the actuator and sliding cam while maintaining the multi-stage adjustment capability through engagement with different grooves.
2Reliability
If wide sliding cams are used to comply with system tolerances, then the valve drive can accommodate tolerance variations, but the weight of the sliding cam increases
Solution Approach 1:
The sliding piece acts as a mediator that absorbs and compensates for dimensional tolerances between the actuator pin and the sliding cam groove. This allows the sliding cam to be designed with reduced width while still maintaining reliable engagement and accommodating tolerance variations, thereby reducing the overall weight of the sliding cam.
3Reliability
If wide sliding cams are used to ensure proper engagement, then engagement reliability is improved, but the surface pressures increase further
Solution Approach 1:
The sliding piece serves as an intermediary that enhances engagement reliability by providing additional contact surfaces and engagement points. The pin engages with the sliding piece, which then engages with the groove in the sliding cam, creating a multi-point contact system that improves engagement reliability while distributing forces to reduce surface pressure on the sliding cam.
Data Source
AI summary
An internal combustion engine having a cylinder head and a cylinder head cover, wherein in order to activate charge cycle valves, at least one rotatably mounted cam shaft is provided with at least one sliding cam which can be slid axially on the respective cam shaft, wherein the respective sliding cam has at least one slotted link section with at least one groove, wherein in order to bring about axial sliding of the respective sliding cam, an actuator is provided, and wherein after axial sliding on the respective cam shaft, the respective sliding cam can be latched in its axial relative position relative to a charge cycle valve to be activated by a locking device which has a first latching element with a plurality of latching depressions and at least one second latching element which interacts with the first latching element.