Pressure Flow Control Sensor Malfunction Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional pressure-type flow rate control devices require evacuation of the flow channel to detect abnormalities in pressure sensors, limiting malfunction detection to maintenance mode and not allowing real-time monitoring during fluid supply processes.
Innovation Solution
A pressure-type flow rate control device and method that computes the difference between upstream and downstream pressure sensor readings when no fluid flows, allowing for pressure sensor malfunction determination without evacuating the flow channel, using a computation control circuit to output signals for determining sensor errors based on detected pressure differences.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If evacuation step is implemented to detect pressure sensor abnormalities, then measurement precision of sensor malfunction detection is improved, but loss of time increases and productivity decreases
Solution Approach 1:
The system performs preliminary malfunction detection by comparing upstream and downstream pressure sensor readings during normal operation before actual failures occur. The computation control part continuously monitors whether P1 equals P2 when flow should be zero, enabling early detection of sensor drift or failures without waiting for maintenance mode or evacuation procedures.
Solution Approach 2:
The malfunction detection operates continuously during normal fluid supply processes rather than requiring separate evacuation steps. The computation control part continuously compares pressure readings from both sensors, maintaining constant monitoring of sensor health without interrupting the primary flow control function, thus achieving continuous useful action for both flow control and sensor validation.
2Reliability
If evacuation step is required for pressure sensor detection, then reliability of sensor malfunction detection is improved, but ease of operation deteriorates
Solution Approach 1:
The system performs self-diagnosis by automatically comparing its own sensor readings without external intervention or special procedures. The computation control part autonomously determines whether P1 should equal P2 under zero-flow conditions and identifies malfunctions independently, enabling the device to self-verify sensor health during normal operation without requiring evacuation or maintenance mode transitions.
Solution Approach 2:
The pressure-type flow rate control device simultaneously performs its primary flow control function and sensor malfunction detection using the same pressure sensors and computation control part. The upstream and downstream pressure sensors serve dual purposes: measuring pressure for flow control calculations and providing data for malfunction detection, eliminating the need for separate detection procedures or additional components.
3Measurement precision
If conventional pressure sensor checking method is used, then measurement precision of sensor readings is maintained, but loss of time increases due to maintenance mode requirement
Solution Approach 1:
The system performs preliminary validation of pressure sensor accuracy by comparing P1 and P2 readings during normal operation. This preliminary check identifies sensor drift or failures before they affect flow control precision, maintaining measurement reliability without requiring separate maintenance mode calibration or evacuation procedures that would interrupt fluid supply processes.
Solution Approach 2:
The malfunction detection operates continuously alongside the fluid supply process, maintaining constant monitoring of sensor accuracy without interrupting production. The computation control part continuously validates whether P1 equals P2 under zero-flow conditions, ensuring measurement precision is maintained while keeping the fluid supply process uninterrupted and productive.
Data Source
AI summary
The pressure-type flow rate control device includes: a restriction part interposed in a flow channel; an upstream-side pressure sensor detecting a fluid pressure on the upstream side of the restriction part; a downstream-side pressure sensor detecting a fluid pressure on the downstream side of the restriction part; a flow control valve provided in the flow channel on the upstream side of the upstream-side pressure sensor; and computation control circuit controlling the flow control valve based on detected values of the upstream-side pressure sensor and the downstream-side pressure sensor, thereby controlling the flow. Under conditions where no fluid flow occurs in the flow channel, the computation control circuit computes the difference between the detected value of the upstream-side pressure sensor and the detected value of the downstream-side pressure sensor, and outputs a signal for pressure sensor malfunction determination based on the computed difference.