Electromagnetic Actuator Variable Annular Gap Damping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The rigid design of the annular gap in electromagnetic actuators leads to slowed movement and impaired dynamics due to differential pressure, limiting damping characteristics and failing to meet switching time requirements, especially in quickly switching actuators.
Innovation Solution
A non-magnetic metal sleeve lines the coil housing, forming a sealing body that varies the annular gap's height over the stroke, allowing independent adjustment of damping characteristics and eliminating the need for an additional sealing component, with the annular gap only becoming effective near the end positions to prevent rebound and ensure quick pressure equalization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a rigid annular gap is used for damping the magnet armature movement, then damping characteristics are provided, but the movement of the magnet armature is slowed down during the entire stroke and switching times are increased
Solution Approach 1:
The annular gap is designed with variable height that changes dynamically during the stroke of the magnet armature. The gap height is larger in the middle position and smaller near the end positions, allowing the damping effect to be activated only when needed (near end positions) while maintaining fast movement during the main stroke.
Solution Approach 2:
The damping effect is localized to specific regions of the stroke rather than being uniformly applied throughout. The annular gap geometry is designed so that the throttling effect occurs only in the region close to the end positions, while the middle region allows free flow for rapid positioning.
2Stability of the object's composition
If a rigid annular gap is used for damping, then damping is provided, but the options for adjusting damping characteristics are limited
Solution Approach 1:
The invention changes the geometric parameters of the annular gap, specifically its height, to control damping characteristics. By varying the gap height as a function of position, multiple damping characteristics can be achieved through different geometric configurations without adding complex adjustment mechanisms.
3Stability of the object's composition
If an additional sealing body is added to form the annular gap, then damping is achieved, but device complexity and manufacturing cost increase
Solution Approach 1:
The sealing body is merged with the coil housing, forming an integral structure. This eliminates the need for separate sealing components while still providing the necessary annular gap for damping. The sealing body with the axial bore is formed as one piece by deep-drawing from the coil housing.
Solution Approach 2:
The sealing body serves multiple functions: it seals the pressure chamber, forms the annular gap for damping, and provides structural support. This multi-functionality reduces the overall number of components needed in the actuator system.
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 maintains the actuator's switching dynamics while allowing targeted adjustment of damping, preventing rebound and reducing mechanical stress and noise, ensuring a controlled and vibration-free movement of the valve tappet.
Implementation Method 1
an overpressure forms in a pressure chamber between the floor and the end face of the magnet armature facing the floor
Implementation Method 2
an annular gap serving as a throttle
Implementation Method 3
the sleeve, which shields the magnet armature from unwanted electromagnetic forces
Implementation Method 4
on which the sealing body is formed in one piece by deep-drawing
Data Source
Figure 1~3
Figure 4~5
AI summary
The actuator has a cylindrical armature (2), a coil housing (5), an inner sealing surface (12) that is formed inside an axial borehole and an outer sealing surface (14) that is provided coaxial to the inner sealing surface for forming an annular gap (11). A sealing body is indirectly fixed at the coil housing, and a pressure chamber is formed at upper and lower end positions with a changeable height of the annular gap within segments of a hub of the armature.