THE MAGNETOELASTIC EFFECT

Methode’s patented non-contact sensor technology utilizes fundamental mechanical and magnetic properties of a material to measure the applied torque or force. The process involves permanently magnetizing the torque transmitting shaft. The elastic deflection of this part causes a change in the magnetic flux which has a linear relationship to the shear stress applied. Highly sensitive sensor coils located in close proximity to the magnetically encoded region sense this change of magnetic field. Due to the sensor orientation in relation to the magnetic field only the desired stress vector is measured, while others, e.g. bending stress, are eliminated. These measurements are highly linear, repeatable and accurate even under harsh environmental and extended operation conditions.

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Sensor Components

Primary Sensor

Every magnetoelastic sensor starts with a hardened alloy steel shaft, tube, plate or pin.

Magnetization

The primary sensor then undergoes a 3 step magnetization and conditioning process.

Torque & Force

Apply a torque or force to the primary sensor and the preconditioned magnetization stored in the sensor will experience a change linear to the applied stress.

Sensing Coils

Miniature sensor coils with micro windings detect the magnetic field changes emitted from the surface of the primary sensor at the magnetized region.

Sensor Electronics

Placed either at the sensing location or a short distance away, the sensor electronics is used for converting the sensed magnetic changes into a usable output signal (analogue or digital).

TORQUE & FORCE SENSING VERSATILITY

Solid Shaft

Outside measurement of torque.

Hollow Tube

Inside & Outside torque measurement.

Plate

Plate with thin cross-section e.g. Flexplate torque sensing.

Tension & Compression

On flat plate or surface section.

Load

On hollow pin. Inside measurement shear.

FEATURES & BENEFITS OF MAGNETOELASTIC SENSOR TECHNOLOGY

HIGH PERFORMANCE

High signal resolution
High bandwidth
Good Linearity
Low hysteresis

EXTREME ROBUSTNESS

Withstands harsh environments
High temperature up to 210°C
Submersible in caustic fluids

EASY INTEGRATION

Compact design
Low complexity
Inside-shaft design option
Cost effective

GREAT RELIABILITY

No accuracy loss over lifetime
No wear-and-tear (non contact)
Component Testing for 480,000 miles equivalent
Key-Life Testing completed on production level
Redundancy possible for safety critical applications

THE MAGNETOELASTIC EFFECT​