Safety switching device for fail-safely disconnecting an electrical load

US10460895B2 · kind B2 · utility

Assignee

• Pilz GmbH & Co. KG · DE

Inventors

• Jürgen Pullmann · Großenhain, DE
• Roland Rupp · Achern, DE
• Christoph Zinser · Wolfschlugen, DE
• Antonio Spataro · Bad Ragaz, CH
• Marco Giger · Wangs, CH
• Hans Schwenkel · Stuttgart, DE

Key dates

• Filing date: Sep 19, 2017
• Grant date: Oct 29, 2019
• Expiry date: Sep 24, 2037

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01H47/002
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

A safety switching device for fail-safely disconnecting an electrical load has an input part for receiving a safety-relevant input signal, a logic part for processing the at least one safety-relevant input signal, and an output part. The output part has a relay coil and four relay contacts. The first and second relay contacts are arranged electrically in series with one another. The third and fourth relay contacts are also arranged electrically in series with one another. The first and the third relay contacts are mechanically coupled to each other and form a first group of positively driven relay contacts. The second and the fourth relay contacts are mechanically coupled to each other and form a second group of positively driven relay contacts. The logic part redundantly controls the first and the second groups of positively driven relay contacts to selectively allow, or to interrupt in a fail-safe manner, a current flow to the electrical load, depending on the safety-relevant input signal. The relay coil is electromagnetically coupled to the first and second groups of positively driven relay contacts so that the logic part can control the relay contacts together via a single rela…