AH-Series Hall Gear Sensors
Product
Introduction
The Series AH Gear Sensor is a self-adjust gear speed sensor
that monitors the movement of titanium-like metals using a Hall
chip internally biased with a magnet and the output is in the
form of a digital sinking current output (open collector).
There is only a single Hall element in the sensor, so alignment
problems are out of concern. The Hall chip and its circuit are
sealed in a metal housing in the form of a probe, which can
effectively avoid electromagnetic interference and moisture. It
has a better SNR than electromagnetic induction sensors and
excellent low-speed performance to achieve "zero-speed"
detection. Currently, the sensors are widely used in the
following fields.
Application
○Camshaft and Crankshaft speed / position detection
○ Transfer speed detection
○ Speedometer
○ Anti-lock brake system (ABS system) Industry
○ Sprocket gear speed detection
○ Speed and distance detection
on chain conveyor belts
○ Stop motion detection
○ High-speed, low-cost proximity switches
Principle
The sensor is designed to sense changes in the magnetic field,
so the output state is changed when the magnetic flux density
reaches a certain value. In other words, the mounting position
of the sensor must be adjusted for different gears so that the
amount of change in magnetic field strength sensed by the Hall
chip in the product can be ensured to meet the operating
conditions. When the external gear rotates, the magnetic field
strength sensed by the Hall chip decreases from the maximum
value, and the sensor output state changes from low to high ,
and it changes into high level when the absolute value of
increment ΔB is greater than 100Gs; while the sensor output
state
changes from high to low when the magnetic field strength
increases from a very small value and it changes into low level
when the absolute value of increment ΔB is greater than
100Gs.