Pilot Solenoid Valve Pressure Balancing for Smooth Piston Switching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional large capacity pilot solenoid valves in HVAC and refrigeration systems experience unstable startup due to strong pressure differences, leading to impact and vibration issues, which affect the lifespan and stability of the system.
Innovation Solution
A flow path switch control device with a pressure balancing control circuit and an adjusting device driven by a pulse signal, gradually increasing the fluid flow area to reduce pressure differences and prevent sudden impacts during valve opening and closing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If a large capacity pilot solenoid valve is used to meet large diameter requirements, then the valve capacity and diameter are increased, but a large pressure difference is formed between the upper and lower sides of the piston causing strong impact and unstable operation
Solution Approach 1:
A pressure balancing hole is introduced as an intermediary element to equalize the pressure between the upper and lower chambers of the piston. This mediator prevents the direct formation of large pressure differences that cause impact, allowing the valve to operate stably at large diameters without compromising reliability.
Solution Approach 2:
The pressure distribution parameters in the piston chambers are changed by introducing the pressure balancing hole. This modifies the pressure differential across the piston, transforming the operating conditions to eliminate harmful impacts while maintaining the large valve diameter required for high capacity applications.
2Speed
If the pilot valve is opened quickly to enable rapid valve response, then the response speed is improved, but the pressure difference changes instantaneously causing strong impact between the piston stopping member and piston
Solution Approach 1:
The pressure balancing hole provides beforehand cushioning by pre-establishing a pressure equalization path. When the pilot valve opens rapidly, the pressure balancing hole gradually equalizes the pressure between chambers, cushioning against sudden pressure differences and preventing impact on the piston stopping member while maintaining fast response capability.
Solution Approach 2:
The pressure balancing hole acts as an intermediary that mediates between the rapid pilot valve opening and the piston movement. It prevents the instantaneous pressure change from directly affecting the piston, thereby eliminating harmful impacts and vibrations while preserving the fast response characteristic.
3Object-affected harmful factors
If a boss is provided on the end cover or inside the piston to avoid direct impact, then some impact protection is achieved, but the pressure difference changes instantaneously at startup still affecting valve life span and system stability
Solution Approach 1:
The pressure balancing hole serves as a more effective intermediary compared to the boss structure. While the boss only provides mechanical cushioning, the pressure balancing hole actively equalizes pressure differences, fundamentally addressing the root cause of impact and vibration, thereby significantly improving valve lifespan and system stability.
Solution Approach 2:
The pressure distribution parameters are changed by the pressure balancing hole, which actively equalizes pressures between chambers. This parameter change approach is more effective than the static boss structure, as it dynamically prevents large pressure differences from forming, thereby enhancing reliability and valve lifespan.
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
The solution ensures smooth operation of the valve by gradually increasing the fluid flow area, reducing pressure differences and eliminating strong vibrations and noise, thereby enhancing the stability and lifespan of the system.
Implementation Method 1
the up or down movement of an iron core is controlled through an electromagnetic force generated by a energized coil
Implementation Method 2
a large pressure difference is formed between the upper and lower sides of a piston to drive the piston to move
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Disclosed herein is a flow path switch control device used in a control system such as HVAC, refrigeration system and the like. In the prior art, since the pressure at an upper portion of a piston will drop instantaneously at the moment when a pilot valve is opened and closed, a large pressure difference is formed between the upper and lower sides of a piston to drive the piston to move, which results in a strong impact between a piston stopping member and the piston. Therefore, the life span of a product and the operating stability of the system will be affected. The flow path switch control device of the present invention includes a fluid inlet, a fluid outlet, a valve device arranged between the fluid inlet and the fluid outlet, and a pressure balancing control circuit. An adjusting device is provided in the pressure balancing control circuit to reduce a pressure change in fluid passing through the pressure balancing control circuit when the flow path switch control device is opened/closed, which enables the flow path switch control device to be smooth during the process of opening or closing, and thus avoid the problem of strong vibration and noise occurred at the moment when the solenoid switch is operated under large pressure difference.