Pilot-Operated Proportional Pressure Valve With Leak-Proof Main Piston Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing pilot-operated directional-control valves face challenges with large opening cross-sections and strokes due to friction and flow losses, particularly when mechanically actuated by springs, leading to inefficiencies and potential safety risks.
Innovation Solution
A proportional valve design featuring a main piston and pilot piston, with leak-proof seals and dynamic seals, ensures precise control and leak-free operation by balancing forces and using solenoid actuation to maintain predefinable positions, minimizing friction and flow losses.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If large opening cross-sections are used to control large volumetric flows, then flow losses are reduced, but the stroke of the main piston increases and friction forces increase
Solution Approach 1:
The valve is divided into a main valve stage with a main piston for controlling large volumetric flows and a pilot valve stage with a pilot piston for controlling the main piston. This segmentation allows the main piston to have a large opening cross-section for reduced flow losses while the pilot piston handles the actuation with minimal stroke requirements.
2Loss of energy
If large opening cross-sections are used to control large volumetric flows, then flow losses are reduced, but friction forces counteracting the switching movement increase
Solution Approach 1:
The valve is divided into a main valve stage with a main piston for controlling large volumetric flows and a pilot valve stage with a pilot piston for controlling the main piston. This segmentation allows the main piston to have a large opening cross-section for reduced flow losses while the pilot piston handles the actuation with minimal stroke requirements.
Solution Approach 2:
The pilot piston acts as an intermediary that controls the main piston indirectly through fluid pressure. This allows the main piston to overcome friction forces more effectively since it is actuated by pressure differential rather than direct mechanical force, enabling large opening cross-sections without proportionally increasing friction resistance.
3Device complexity
If mechanical actuation by spring is used, then the valve structure is simple, but the spring force may be too small compared to frictional force for resetting the piston
Solution Approach 1:
The pilot piston acts as an intermediary that controls the main piston indirectly through fluid pressure. This allows the main piston to overcome friction forces more effectively since it is actuated by pressure differential rather than direct mechanical force, enabling large opening cross-sections without proportionally increasing friction resistance.
Solution Approach 2:
The pilot-operated design replaces direct mechanical spring actuation of the main piston with a fluid pressure-based control system. The pilot piston uses fluid pressure differentials to control the main piston, substituting mechanical force transmission with hydraulic/pneumatic actuation that can more effectively overcome friction forces.
4Reliability
If solenoid system is dimensioned large to meet stroke and force requirements, then valve performance improves, but device complexity and size increase
Solution Approach 1:
The valve is divided into a main valve stage with a main piston for controlling large volumetric flows and a pilot valve stage with a pilot piston for controlling the main piston. This segmentation allows the main piston to have a large opening cross-section for reduced flow losses while the pilot piston handles the actuation with minimal stroke requirements.
Solution Approach 2:
The pilot piston acts as an intermediary that controls the main piston indirectly through fluid pressure. This allows the main piston to overcome friction forces more effectively since it is actuated by pressure differential rather than direct mechanical force, enabling large opening cross-sections without proportionally increasing friction resistance.
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 design achieves reliable, leak-free operation under high operational demands, ensuring safe and efficient control of volumetric flows without unintentional leakage, suitable for use as a load valve.
Implementation Method 1
it being possible to actuate the pilot piston by means of a solenoid device
Implementation Method 2
due to the associated pressure drop, the main piston moves into a control position which can be actuated by the fluid quantity
Data Source
AI summary
The disclosure relates to a valve, e.g., a proportional valve, comprising a main piston for actuating a main volumetric flow and a pilot piston for actuating a pilot volumetric flow. The main piston and the pilot piston are guided in a valve housing in a longitudinally movable manner, and the pilot piston can be actuated using a magnetic device. The position of the main piston can be set using the pilot piston which, based on the movement position thereof, signals the fluid pressure acting on the main piston into a pilot chamber via a fluidic connection or cuts of the fluid connection and connects the pilot chamber to a tank or low-pressure side via another fluidic connection into which a valve is introduced that closes in a leak-proof manner as soon as a fluidic connection is produced between the main piston and the pilot chamber.