Encoders enable position control with high accuracy

Encoders are classified as electronic components, and are sensors that detect the amount and angle of movement of rotating and horizontally moving equipment and devices, and output electrical signals.
Since they excel in high-precision control, they are widely used in office equipment, machine tools, and industrial robots.
In recent years, the use of reflective encoders has increased in ultra-compact actuators, which are difficult to control, and they are also used in collaborative robots that require less space.

Search for encoders by shape

<Types of encoders>

Principle of electrical signal detection

Optical encoders: high accuracy and high magnetic fields
Magnetic encoders: simple and compact design, high durability

Types of electrical signal detection

Linear encoders: measuring linear shaft movement and outputs as position information
Rotary encoders: measuring rotational movement (angle) and outputs it as position information

Output methods

“Incremental type” measuring the relative position

It starts from an arbitrary starting point, counts in a regular pattern, and outputs pulses according to the amount of movement.

“Absolute type” measuring the absolute position

The absolute position from the origin is detected by the rotation angle of the encoder and the data is output.

What is a photo-interrupter?


The encoder disk, which is used to measure the number of rotations of the motor, is mounted between the U-shaped parts shown in the illustration. This U-shaped component is called a “photo-interrupter”.

The photo-interrupter contains an infrared LED and a photo IC placed between the discs. Infrared light is irradiated and the number of times the LED light passes through the slit hole in the disc is measured.