Pilot Check Valve Residual Pressure Exhaust Sealing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing pilot check valves with residual pressure exhaust units face issues where a failure in sealing properties can lead to the unintended exhaustion of pressure fluid from fluid pressure devices during emergencies, such as power supply stoppages, resulting in loss of check function.
Innovation Solution
A pilot check valve design featuring a seal portion in the residual pressure exhaust path and an operation unit that allows selective movement of the check valve element and seal portion to maintain pressure fluid containment, even in case of sealing failures, by allowing fluid flow through the residual pressure exhaust path when necessary.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the residual pressure exhaust path is connected downstream of the check valve element, then residual pressure can be exhausted from the fluid pressure device, but the check function may be lost if sealing fails
Solution Approach 1:
The invention divides the exhaust path into two separate segments: one connected downstream of the check valve element (for normal residual pressure exhaustion) and another connected upstream of the check valve element (for emergency exhaustion). This segmentation ensures that if the downstream path fails, the upstream path remains isolated from the exhaust hole, preventing unintended exhaustion while maintaining the check function.
Solution Approach 2:
The invention introduces an intermediary structure (the upstream exhaust path connection) that acts as a backup route. This intermediary path, connected upstream of the check valve element, serves as a mediator to prevent direct communication between the sealed pressure fluid and the exhaust hole when the primary downstream path fails, thereby protecting the check function.
2Reliability
If a seal portion is added to block flow in the residual pressure exhaust path, then pressure fluid containment is improved, but device complexity increases
Solution Approach 1:
The invention applies local quality by placing a seal portion only at the specific location where the residual pressure exhaust path connects to the upstream side of the check valve element. This localized sealing approach ensures pressure fluid containment at the critical interface without requiring sealing throughout the entire exhaust path, thereby minimizing the increase in device complexity while maintaining reliability.
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 ensures that pressure fluid is effectively held downstream of the check valve element during emergencies, maintaining the check function and preventing unintended exhaustion, thus ensuring the integrity of fluid pressure devices.
Implementation Method 1
a check valve element that is provided in the main path, allows a flow of a pressure fluid from a first side in communication with the input port toward a second side in communication with the output port, the check valve element being selectively moved, by supply or discharge of a pilot fluid
Implementation Method 2
a seal portion that is provided in the residual pressure exhaust path and blocks a flow of a pressure fluid from the connecting portion of the main path toward a side of the exhaust hole
Data Source
AI summary
[Solution] A pilot check valve includes a first body that has input and output ports, a main path 13 that is in communication these ports, and a check valve element that allows a flow of a pressure fluid from the input port toward the output port. The valve element blocks or allows a flow toward the input port side by supply or discharge of a pilot fluid and has a residual pressure exhaust path connected between the main path and an exhaust hole, a seal member that is provided in the exhaust path, and a push rod that moves the check valve element to a position where a flow of a pressure fluid toward the input port side in the main path is allowed and moves the seal member to a position where a flow toward the exhaust hole is allowed.