Hydraulic Lash Adjuster External Oil Groove Air Venting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing valve deactivation systems in variable displacement engines face challenges with air trapped in the latch pin circuit, which increases the time needed for mode transitions, and the complexity and cost of manufacturing dual-function hydraulic lash adjusters with internally coupled galleries limit their functionality and modularity.
Innovation Solution
A method is introduced where a metered hydraulic fluid passage on the outer surface of the hydraulic lash adjuster allows hydraulic fluid to flow between annular galleries at different heights and orientations, enabling efficient air displacement and mode transitions by controlling the pressure to the auxiliary valve actuation system, allowing for flexible positioning of galleries independent of the hydraulic lash adjuster's orientation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If air is present in the latch pin circuit, then the mode transition time increases, but the system complexity remains the same
Solution Approach 1:
The hydraulic lash adjuster is pre-filled with hydraulic fluid and designed to automatically vent trapped air during normal operation. The air venting passage provides a predetermined path for air to escape before it can interfere with mode transitions, eliminating the need for additional air removal mechanisms while maintaining fast transition times.
Solution Approach 2:
The air venting passage extracts and removes trapped air from the latch pin circuit by providing a dedicated escape route. This separates the air removal function from the main hydraulic circuit, allowing the hydraulic system to operate efficiently without air interference while keeping the overall design simple.
2Adaptability or versatility
If dual-function hydraulic lash adjuster with internally coupled galleries is used, then the functionality is integrated, but the manufacturing complexity and cost increase
Solution Approach 1:
The hydraulic lash adjuster is designed with separate, independently manufacturable components including the body, plunger, and air venting passage. These segments can be manufactured separately using standard processes and then assembled, avoiding the need for complex internal passages that would require specialized manufacturing while still achieving dual-functionality through proper fluid coupling.
Solution Approach 2:
The air venting passage acts as an intermediary element that couples the first and second galleries without requiring direct internal integration. This mediator component provides the necessary fluid communication path while allowing the galleries to be positioned independently, simplifying manufacturing and assembly.
3Stability of the object's composition
If first and second galleries are placed at equal heights on opposite sides, then the structural symmetry is achieved, but the modularity and orientation flexibility are limited
Solution Approach 1:
The first and second galleries are positioned at different heights and locations within the hydraulic lash adjuster body, breaking the symmetry to achieve greater orientation flexibility. This asymmetric arrangement allows the adjuster to function correctly in various orientations and with different engine configurations without requiring additional orientation features.
Solution Approach 2:
Instead of positioning galleries only in opposite directions (one-dimensional arrangement), the invention utilizes vertical positioning at different heights (adding a second dimension). This three-dimensional arrangement of galleries provides greater design flexibility and modularity while maintaining proper fluid coupling through the air venting passage.
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 solution reduces the time required for mode transitions, enhances the modularity and cost-effectiveness of the hydraulic lash adjuster, and allows for seamless operation across various engine conditions by independently managing hydraulic pressure to the auxiliary valve actuation system.
Implementation Method 1
a metered hydraulic fluid passage on the outer surface of the hydraulic lash adjuster allows hydraulic fluid to flow between annular galleries
Implementation Method 2
controlling the pressure to the auxiliary valve actuation system
Data Source
AI summary
Methods and systems are provided for a valve actuating mechanism. In one example, a method includes flowing hydraulic fluid from a first gallery to a second gallery via an external metered hydraulic fluid passage of a hydraulic lash adjuster.