Applications for rotary coding switches: from volume adjustment to robot control

Rotary coding switch, also known as rotary switch, is an important electronic switching device widely used in various electronic equipment and systems. It has the important function of switching different functions or options through rotation operation, which is usually accompanied by "click" feedback that the user can perceive, making its operation more intuitive and user-friendly.

The working principle of this switch can be divided into the following key parts:

1. Contactor: One of the core components of a rotary encoding switch, usually composed of metal sheets or carbon contacts. When the knob is turned, the contactor makes or breaks a fixed pin or circuit, changing the state of the switch. This change in mechanical contact will cause the flow or interruption of current, thereby generating corresponding electrical signals.

2. Photoelectric conversion: In order to detect the rotation direction and number of steps of the knob, photoelectric conversion technology is usually used. The photoelectric converter includes a light-emitting diode (LED) and a photosensitive diode (Photodiode). The LED emits infrared or visible light onto the dial of the rotary encoder switch.

As the knob is turned, the transparent spaces and opaque markings on the dial cause the intensity of light hitting the photodiode to change. By detecting the intensity of light received by the photodiode, the position and direction of rotation of the knob can be determined.

3. Pulse signal generation: According to the rotation direction and step number of the knob, the photoelectric converter will generate the corresponding pulse signal related to the position and rotation direction of the knob. Specifically, clockwise rotation may induce the generation of positive pulses, while counterclockwise rotation may induce the generation of negative pulses.

By detecting the number and direction of these pulse signals, the absolute position and status of the knob can be determined. These signals are typically recognized and interpreted by a microprocessor or other electronic device to enable switching of functions or options associated with the rotary encoded switch.

Rotary encoder switches are generally divided into the following main types:

1. Incremental rotary encoding switch: This is the most common type, which generates a pulse signal according to the position and direction of the knob, and each rotation increases or decreases a step number. It is usually used to adjust parameters such as volume, brightness, frequency, etc., as well as menu navigation and selection.

2. Absolute rotary encoding switch: This type can accurately determine the absolute position of the knob, using a dial with multiple positions and marks, and detecting the position of the knob through a photoelectric converter. Each location is associated with a unique coded value, enabling precise selection of a specific feature or option.

3. Programmed rotary coding switch: This is a special type of rotary coding switch that can be customized through programming. It usually has a display or LED indicator light that can display information about the current options or functions and allow the user to program settings as needed. This type of switch is typically used in applications that require flexibility and personalization, such as music equipment, game controllers, and industrial automation systems.

Overall, rotary encoded switches are an indispensable component in electronic equipment, providing precise control of functions and options for a variety of devices. An in-depth understanding of their working principles and different types will help to better understand their importance and applications in the field of electronics.