The response time of frame sensors for example can be

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: otted disc or a linear scale is sensed. In this way, it is possible to achieve a digital potentiometer without sliding contact. Relatively high switching frequencies are possible, for example up to 1 MHz. Also light barrier sensors are available, which can detect the direction of movement of an object. © Festo Didactic GmbH & Co. KG • FP 1110 241 15. Special designs and variants of proximity sensors 15.2.2 Frame barrier sensors Frame barrier sensors operate according to the principle of a light curtain. On two opposite sides of the frame a large number of emitters and receivers are fitted in close alignment, completely covering the inside of the frame with a light curtain. Fig. 15.2.2: Frame light barrier Frame sensors are used preferably to detect small parts falling through the frame, for example for ejection monitoring of punched or pressed parts. Because of their application in dynamic processes, frame sensors generally only have a dynamic switching behaviour. Permanently existing parts, such as a transparent conveyor tube which may be contaminated by dust and oil are therefore not detected. The response time of frame sensors, for...
View Full Document

This note was uploaded on 11/01/2012 for the course CHEMICAL 102 taught by Professor Jamesrodriguez during the Spring '12 term at Universidad Politécnica de Cartagena.

Ask a homework question - tutors are online