Classification and working principle of magnetic encoder

According to different application principles, AGV encoders can be divided into photoelectric encoders and magnetic encoders. They have different advantages and characteristics in many applications:

Optical encoder: The optical encoder uses the principle of photoelectric effect to convert physical signals into electrical signals. Infrared light emitted by an LED light source passes through a code disc engraved with a grating and a matching light shield to illuminate the optical sensor array, and then the optical sensor array converts these light and dark pulse information or position information into electrical signals. Optical encoders have high accuracy and high anti-interference, and can be widely used in various industries.

Magnetic encoder: The magnetic encoder uses the principle of magnetoelectric effect to convert physical signals into electrical signals. A permanent magnet is embedded on the rotating shaft of the encoder, and the sensor converts it into a pulse signal or position information by sensing the magnetic field of the magnet. Due to its working principle, the magnetic encoder has a very high degree of protection, up to IP96K, and can have high shock resistance and vibration resistance in harsh mechanical environments.

Fiber optic encoders: Fiber optic encoders are sometimes called "explosion-proof" encoders and are used where methane, propane or other extremely flammable gases are present. Use lasers and phototransistors to generate output codes. Often used in explosion-proof applications with extremely flammable gases.

Capacitive encoders: Capacitive encoders generate output codes by using high-frequency reference signals to detect changes in capacitance. Capacitive encoders are not recommended for explosion-proof applications, but due to the use of proprietary capacitive technology, they can withstand environments similar to magnetic encoders Factors, and are usually better than optical encoders. According to different output signal types, AGV encoders can be divided into incremental encoders and absolute encoders:

Incremental encoder: The incremental encoder converts the measured signal into a pulse signal, and has the ability to measure the speed, length, and position of the tested equipment.

Absolute value encoder: The absolute value encoder corresponds to a code for each detected position, no matter what the state, it can determine the position change of the device.

Factors to consider when choosing an encoder:

01 temperature compensation

Encoder products are equipped with a dedicated circuit to ensure that the signal quality remains at the same high level when the operating temperature range is exceeded.

02Short circuit protection

The encoder ensures that the encoder will not be damaged if a short circuit or wrong wiring occurs in the signal output channel. Once the encoder is correctly wired, it will resume work.

03Reverse polarity protection

The power supply range of the encoder is 5-30VDC and 10-30VDC. In the wrong wiring of the power cord, the sensor is not damaged. Once the sensor is correctly wired, it will resume operation.

04Environmental requirements

When the encoder is in use, environmental factors have a significant impact on the service life of the encoder.

05 working temperature

The ambient temperature when the encoder can work at normal temperature, and the drop in operating temperature directly affects the service life and use effect of the encoder.

06 Mechanical strength

Encoder products adopt double-bearing or multi-bearing support structure to ensure the mechanical load-carrying capacity of the encoder to a greater extent. At the same time, the bearing directly adopts the design of mutual limit of mechanical mechanism.

The bearing is treated with special grease, and the bearing can withstand extreme temperature environment, high speed, high load and constant commutation rotation.