Single-Sensor Cylinder Stroke Timing via Magnetic Flux Thresholds
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional fluid pressure cylinder position detecting devices require multiple magnetic sensors to measure piston movement time, which is inefficient and complex.
Innovation Solution
A single uniaxial magnetic sensor is used to detect the magnetic flux density of a magnet on the piston, with threshold values defining starting and ending points of piston movement, allowing for the measurement of time required for a predetermined stroke using a single sensor.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If multiple magnetic sensors are used to detect piston position at different points, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The patent merges the functions of multiple magnetic sensors into a single uniaxial magnetic sensor by utilizing the magnetic flux density distribution curve characteristics. The single sensor detects both the positive peak (corresponding to first position) and negative peak (corresponding to second position) of the magnetic flux density, thereby determining multiple piston positions without requiring multiple sensors.
Solution Approach 2:
The patent transitions from using multiple sensors at different spatial positions to using a single sensor that detects variations in magnetic flux density magnitude and polarity. By monitoring the curve characteristics (positive/negative peaks) of the magnetic flux density signal over time, the system can identify different piston positions through signal characteristics rather than spatial arrangement.
2Device complexity
If a single magnetic sensor is used to detect piston movement, then device complexity is reduced, but measurement precision deteriorates
Solution Approach 1:
The patent utilizes changes in magnetic flux density parameters (magnitude and polarity) as the piston moves. The magnet is configured to generate a magnetic flux density distribution that produces distinct positive and negative peaks at different piston positions. By monitoring these parameter changes in the signal from a single uniaxial magnetic sensor, accurate position detection is achieved without requiring multiple sensors.
Solution Approach 2:
The system continuously monitors the magnetic flux density signal and uses threshold detection to identify when the signal exceeds or falls below predetermined values. This feedback mechanism allows the control unit to accurately determine piston position transitions by detecting when the magnetic flux density crosses specific thresholds, maintaining measurement precision with a single sensor.
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
Enables efficient determination of starting and ending points for piston movement, simplifying the measurement process and reducing the number of sensors needed, while accurately measuring piston movement time.
Implementation Method 1
a magnetic sensor configured to detect a magnetic flux density of a magnet mounted on the piston
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A fluid pressure cylinder movement time sensor is equipped with a single magnetic sensor (12). A point in time at which a magnetic flux density detected by the magnetic sensor exceeds or falls below a first threshold value is defined as one of a starting point or an end point, and a point in time at which the magnetic flux density detected by the magnetic sensor exceeds or falls below a second threshold value is defined as another one of the starting point or the end point.