This preview shows page 1. Sign up to view the full content.
Unformatted text preview: ical radiation
– Sensors for chemical substances
– Sensors for physical matter characteristics 15 1. General notes 1.5
Proximity sensors In this textbook, sensors dealing with "discrete position" form the main topic, i.e.
sensors which detect whether or not an object is located at a certain position. These
sensors are known as proximity sensors. Sensors of this type provide a "Yes" or
"No" statement depending on whether or not the position, to be defined, has been
taken up by the object. These sensors, which only signal two status, are also known
as binary sensors or in rare cases as initiators.
With many production systems, mechanical position switches are used to
acknowledge movements which have been executed. Additional terms used are
microswitches, limit switches or limit valves. Because movements are detected by
means of contact sensing, relevant constructive requirements must be fulfilled. Also,
these components are subject to wear. In contrast, proximity sensors operate
electronically and without contact.
The advantages of contactless proximity sensors are:
• Precise and automatic sensing of geometric positions
• Contactless sensing of...
View Full Document
- Spring '12