Protective device operating without contact, in particular light barrier grid

US5998785A · kind A · utility

Assignee

• SICK AG · DE

Inventors

• Michael Beck · Waldkirch, DE
• Harald Hettich · Gundelfingen, DE
• Karl-Heinz Suss · Waldkirch, DE

Key dates

• Filing date: Mar 21, 1997
• Grant date: Dec 7, 1999
• Expiry date: Mar 21, 2017

Classification

• Technology area (CPC G): Physics
• CPC primary: G01V8/10
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A protective device operating in contact-free manner, such as in particular a light barrier grid (10), including a transmitter unit and/or a receiver unit (12) for generating and/or for receiving sensing signals, such as in particular light signals which serve for the contact-free monitoring of a protective area. At least the transmitter unit and/or the receiver unit (12) of the protective device is accommodated in a pressure-tight, preferably tubular housing (14), which is at least partly permeable for the sensing signals and which in particular includes cable lead-throughs (16) which ensure explosion protection.