Valve Spindle Segmentation for Fast Switching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing valves used in application devices, such as spray guns, particularly those operating electrostatically, face challenges in achieving fast switching times between closed and release positions due to limited effective area for pressure fluid action, leading to potential voltage flashovers and safety risks in high electrical potential environments.
Innovation Solution
The valve design incorporates multiple piston elements connected via radial channels to an external circumferential groove, allowing increased effective area for pressure fluid action, and uses insulating materials for the valve spindle and conductive materials for the sealing element to prevent voltage flashovers, while maintaining compact dimensions and efficient sealing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If a single piston element is used in known valves, then the structure is simple, but the effective area for pressure fluid action is limited, resulting in slow switching times
Solution Approach 1:
The valve spindle is divided into multiple piston elements (first piston element with first piston chamber, second piston element with second piston chamber) instead of using a single piston element. This segmentation increases the total effective area for pressure fluid action, enabling faster switching times while maintaining manageable structural complexity through modular design
2Speed
If the working pressure of the pressure fluid is increased to accelerate valve spindle movement, then switching time is reduced, but the overall dimensions of the valve must be increased
Solution Approach 1:
Multiple piston chambers are connected via radial channels to a common external circumferential groove, allowing the pressure fluid to act simultaneously on multiple piston elements. This merging of pressure fluid pathways enables increased effective area without requiring higher working pressure or larger valve dimensions
3Strength
If the valve spindle is made of conductive metallic material, then structural strength is ensured, but voltage flashovers and sparks can occur in high electrical potential environments
Solution Approach 1:
The valve spindle is constructed from composite materials combining metallic components (for structural strength in piston elements and valve seat) with electrically insulating materials (such as plastic or ceramic coatings on the valve spindle surface). This composite structure maintains mechanical strength while providing electrical insulation to prevent voltage flashovers in high potential environments
4Ease of manufacture
If sealing means are not provided for piston elements, then manufacturing is simpler, but pressure drop in piston chambers occurs and pressure fluid is not used effectively
Solution Approach 1:
Sealing means in the form of flexible sealing rings made of elastomer material (particularly perfluoroelastomer) are provided for the piston elements. These thin flexible sealing films effectively prevent pressure drop in the piston chambers while maintaining ease of manufacture through simple installation and replacement capabilities
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 design accelerates valve spindle movement, reducing switching times without increasing pressure or size, and mitigates voltage flashover risks through effective insulation and sealing, enhancing safety and operational efficiency.
Implementation Method 1
The effective area of the valve spindle can be effectively increased by the at least two piston elements, on which the pressure fluid can exert a force in order to move the valve spindle. As a result, the movement of the valve spindle is accelerated
Implementation Method 2
sealing means are provided which seal the first piston element and/or the second piston element against the inner wall of the associated first or second piston chamber and comprise an elastomer material, in particular a perfluoroelastomer material. As a result, a particularly good sealing effect can be achieved, so that a pressure drop in the piston chambers is avoided
Implementation Method 3
the second free end of the valve spindle is in contact with the environment through the valve housing and is made of an electrically insulating material with good electrical insulation. In practice, it has proven advantageous if the insulation material is a plastic, in particular a plastic from the group of polyether ketones, preferably a polyaryl ether ketone (PEK) or a polyether ether ketone (PEEK)
Implementation Method 4
With regard the sealing element, on the other hand, it is favorable if this is made from an electrically conductive material, in particular from a doped plastic. In this way, potential equalization can take place between the valve stem and a valve seat. The sealing element is preferably made of PA12 graphite
Data Source
AI summary
A valve for use in conjunction with an application device comprises a valve housing (12) and a valve spindle (32) which bears a sealing element (40) at a first free end (36) outside the valve housing (12) and, within the valve housing (12), is mounted displaceably between a closed position and a release position. The valve spindle (32) comprises at least one first piston element (44) and at least one second piston element (54), wherein the first piston element (44) is guided in a first piston space (20) and the second piston element (54) is guided in a second piston space (22), said piston spaces being bounded by the valve housing (12). A pressure fluid can be supplied in each case to the first piston space (20) and to the second piston space (22) in such a manner that a force acting in the same direction is exerted on the first piston element (44) and on the second piston element (54).