läheisyysanturi

A proximity sensor, known in Finnish as a läheisyysanturi, is a non-contact sensor apparatus used to detect the presence of objects. These sensors are commonly found in industrial settings, robotics, and consumer electronics. They operate by emitting an electromagnetic field or a beam of light (or other electromagnetic radiation) and observing changes in the field or reflected beam.

There are several types of proximity sensors, each employing different detection principles. Inductive proximity sensors detect metallic objects by generating an oscillating magnetic field. When a metallic object enters the field, it induces eddy currents, which absorb energy from the oscillator and cause a change in amplitude. Capacitive proximity sensors can detect both metallic and non-metallic objects by sensing changes in capacitance. They create an electrostatic field, and when an object enters this field, it alters the capacitance between the sensor and the object. Photoelectric proximity sensors use a light beam, typically infrared or visible light, to detect objects. They consist of an emitter and a receiver. The emitter sends out a beam, and the receiver detects when the beam is interrupted or reflected.

The primary advantage of proximity sensors is their ability to detect objects without physical contact, preventing wear and tear on both the sensor and the object being detected. This non-contact operation also allows for the detection of fragile or moving objects. Proximity sensors are essential components in automation systems for tasks such as counting, positioning, and safety interlocks.