Sensores - Sensors for handling and processing technology...

093046 EN
Sensors for
handling and
processing
technology
Proximity sensors
Textbook FP 1110

Order No.: 093046
Description: NAEH-SCH.LHRBCH
Designation: D:LB-FP1110-EN
Edition: 09/2003
Author: Frank Ebel, Siegfried Nestel
Graphics: Barbara Böhland, Frank Ebel
Layout: 04.09.2003, Beatrice Huber
© Festo Didactic GmbH & Co. KG, 73770 Denkendorf/Germany, 2003
Internet: www.festo.com/didactic
E-mail: [email protected]
The copying, distribution and utilization of this document as well as the
communication of its contents to others without expressed authorization is
prohibited. Offenders will be held liable for the payment of damages. All rights
reserved, in particular the right to carry out patent, utility model or ornamental
design registration.

© Festo Didactic GmbH & Co. KG • FP 1110
3
Notes on the layout of this book _________________________________________ 7
1. General notes ________________________________________________ 11
1.1 The importance of sensor technology _____________________________ 11
1.2 Terms _______________________________________________________ 11
1.2.1 Sensor ______________________________________________________ 11
1.2.2 Sensor component_____________________________________________ 12
1.2.3 Sensor system ________________________________________________ 12
1.2.4 Multi-sensor system ___________________________________________ 13
1.3 Typical output signals of sensors _________________________________ 13
1.4 Binary and analogue sensors ____________________________________ 15
1.4.1 Binary sensors ________________________________________________ 15
1.4.2 Analogue sensors _____________________________________________ 15
1.5 Proximity sensors _____________________________________________ 16
1.5.1 Overview of position sensors ____________________________________ 17
1.5.2 Operating voltages ____________________________________________ 18
1.6 Fields of application for proximity sensors__________________________ 18
2. Mechanical position switches ___________________________________ 25
2.1 Electro-mechanical position switches _____________________________ 25
2.1.1 Function description ___________________________________________ 25
2.1.2 Technical characteristics ________________________________________ 26
2.1.3 Notes on installation ___________________________________________ 28
2.1.4 Examples of application ________________________________________ 30
2.2 Mechanical-pneumatic position switches __________________________ 31
2.2.1 Function description ___________________________________________ 31
2.2.2 Technical characteristics ________________________________________ 32
2.2.3 Notes on application ___________________________________________ 32
2.2.4 Examples of application ________________________________________ 32
2.3 Exercises ____________________________________________________ 33
Contents

Contents
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© Festo Didactic GmbH & Co. KG • FP 1110
3. Magnetic proximity sensors _____________________________________ 35
3.1 Reed proximity sensors_________________________________________ 35
3.1.1 Function description ___________________________________________ 35
3.1.2 Technical characteristics ________________________________________ 36
3.1.3 Notes on application ___________________________________________ 38
3.1.4 Examples of application ________________________________________ 40
3.2 Contactless magnetic proximity sensor ____________________________ 42
3.2.1 Function description ___________________________________________ 42
3.2.2 Technical characteristics ________________________________________ 43
3.2.3 Notes on application ___________________________________________ 44
3.2.4 Examples of application ________________________________________ 45
3.3 Magnetic-pneumatic proximity sensors ____________________________ 45
3.3.1 Function description ___________________________________________ 45
3.3.2 Technical characteristics ________________________________________ 46
3.3.3 Notes on application ___________________________________________ 46
3.3.4 Example of application _________________________________________ 46
3.4 Exercises ____________________________________________________ 47
4. Inductive proximity sensors _____________________________________ 49
4.1 Function description ___________________________________________ 49
4.2 Technical characteristics ________________________________________ 52
4.3 Notes on application ___________________________________________ 53
4.4 Examples of application ________________________________________ 55
4.5 Exercises ____________________________________________________ 58
5. Capacitive proximity sensors ____________________________________ 61
5.1 Function description ___________________________________________ 61
5.2 Technical characteristics ________________________________________ 64
5.3 Notes on application ___________________________________________ 64
5.3.1 Considerations for application ___________________________________ 65
5.4 Examples of application ________________________________________ 65
5.5 Exercises ____________________________________________________ 69

Contents
© Festo Didactic GmbH & Co. KG • FP 1110
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6. Optical proximity sensors ______________________________________ 71
6.1 General characteristics _________________________________________ 71
6.1.1 Emitter and receiver elements in optical proximity sensors ____________ 72
6.1.2 Construction of an optical proximity sensor_________________________ 73
6.1.3 Operating margin for optical proximity sensors______________________ 74
6.1.4 Variants of optical proximity sensors ______________________________ 77
6.2 Through-beam sensors _________________________________________ 78
6.2.1 Function description ___________________________________________ 78
6.2.2 Technical characteristics ________________________________________ 78
6.2.3 Notes on application ___________________________________________ 79
6.2.4 Examples of application ________________________________________ 80
6.3 Retro-reflective sensors ________________________________________ 81
6.3.1 Function description ___________________________________________ 81
6.3.2 Technical characteristics ________________________________________ 82
6.3.3