Pneumatic Valve Shaft Split for Stable Seal Pressing Force
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In pneumatic valves, excessive pressing force against the seal member can lead to creep and increased leakage, which is difficult to control due to variations in environmental conditions and manufacturing errors, especially when using resin seal members.
Innovation Solution
The pneumatic valve design splits the shaft into two members with a biasing member sandwiched between them, including a stopper in the movement path of one member, allowing controlled pressing force management by adjusting the internal pressure of the actuating pressure chamber and utilizing disc springs to accumulate elastic energy, thereby separating the pressing force control from the force acting on the first member.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the valve body is pressed against the seal member with a specified axial force by a spring, then the valve achieves reliable sealing, but the pressing force may become excessive depending on operating conditions, environmental conditions, or manufacturing errors, causing creep and excessive leakage
Solution Approach 1:
The shaft is divided into two separate members: a first member that receives pressure from the actuating pressure chamber and a second member that includes the valve body. This segmentation allows the pressing force to be controlled independently from the actuating force, enabling precise control of the sealing force while maintaining reliable sealing.
Solution Approach 2:
A biasing member (spring) is introduced as an intermediary element between the first member and the second member. This biasing member accumulates elastic energy when the first member contacts the stopper and provides a controlled pressing force to the valve body, decoupling the actuating force from the sealing force and preventing excessive pressing force under varying conditions.
2Reliability
If resin is used for the seal member, then the valve achieves good sealing properties, but the creep limit varies depending on environmental conditions, making it necessary to strictly control the sealing force
Solution Approach 1:
By segmenting the shaft into two members with independent force control, the invention enables strict control of the sealing force applied to the resin seal member, compensating for the material's sensitivity to environmental conditions and varying creep limits.
Solution Approach 2:
The invention changes the control parameter from direct pressure application to spring-based force application. The biasing member's elastic energy storage and gradual force application provide stable, controlled pressing force that adapts to varying environmental conditions, maintaining consistent sealing performance regardless of temperature or pressure variations.
3Device complexity
If the shaft is a single integrated component, then the structure is simple, but the pressing force cannot be controlled separately from the actuating force
Solution Approach 1:
The shaft is segmented into two members that can move relative to each other axially. This segmentation enables independent control of the pressing force through the biasing member while maintaining a relatively simple overall structure, resolving the contradiction between structural simplicity and force control capability.
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 configuration effectively manages the pressing force of the valve body against the seal member, suppressing creep and leakage, while allowing precise control and stabilization of the sealing force, even under varying conditions.
Implementation Method 1
a biasing member that is sandwiched between the first member and the second member, has an elastic energy accumulated therein in a state where the first member is in contact with the stopper, and presses the valve body against the seal member
Implementation Method 2
when the closing actuating gas is supplied to the closing actuating pressure chamber, an internal pressure of the closing actuating pressure chamber is raised, the shaft is moved in the axial direction toward the sealing member
Data Source
Figure 1
Figure 2A~2B
Figure 3
AI summary
Provided is a pneumatic valve (1) in which a seal member (13); a shaft (4) provided with a valve body (2) capable of abutting against the seal member (13); and a valve-actuating pressure chamber (21) that moves the shaft (4) in an axial direction to actuate the valve body (2) is provided within a valve casing (3). The shaft (4) has a first member (30) that receives pressure from the valve-actuating pressure chamber (21), and a second member (40) that includes the valve body (2) and is movable relative to the first member (30) in the axial direction. The pneumatic valve (1) further has a stopper (50) that is provided in a movement path of the first member (30), and a disc spring (51) that is sandwiched between the first member (30) and the second member (40), has elastic energy accumulated therein in a state where the first member (30) is in contact with the stopper (50), and presses the valve body (2) against the seal member (13).