Double-Armature Relay Layout for Safe Redundant Switching Paths

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing relay devices and safety switching devices lack safety in switching paths equipped with a single relay, which compromises operational reliability and safety standards, especially in critical applications requiring fail-safe shutdowns.

Innovation Solution

A relay device with a double armature relay design, where all movable parts are duplicated for redundancy, and a safety switching device that uses this relay to provide switch-on and switch-off delays with improved safety properties, reducing installation space and costs while ensuring all switching paths are safe.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single relay is used in switching paths, then device complexity is reduced, but safety and operational reliability deteriorate

Engineering Contradiction:
Improverelay configurationVSAvoidswitching path safety
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The relay device is segmented into multiple independent relay units (first relay unit, second relay unit, third relay unit) with distinct switching paths. Each relay unit can be configured with different numbers of relays (single relay or multiple relays in series/parallel), allowing safety-critical paths to use redundant configurations while non-critical paths use simpler single-relay configurations, thus resolving the contradiction between device complexity and safety.

Inventive Principle:
Principle #1Segmentation

2Reliability

If multiple relays are arranged in series to ensure safety, then switching path safety is improved, but installation space and cost increase

Engineering Contradiction:
Improveswitching path safetyVSAvoidinstallation space
Core Design Contradiction:
ReliabilityVSArea of stationary object

Solution Approach 1:

Multiple relay units are integrated into a single housing with shared structural components, terminal blocks, and mounting interfaces. The relays are arranged in a compact configuration where space is optimized through common support structures and integrated circuit boards, reducing the overall installation footprint while maintaining the safety benefits of multiple relays in series.

Inventive Principle:
Principle #5Merging (Combining)

3Reliability

If redundant relay configurations are implemented, then operational reliability is improved, but device complexity and cost increase

Engineering Contradiction:
Improveoperational reliabilityVSAvoidrelay configuration
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

Different switching paths within the relay device have different safety requirements. The invention applies local quality by configuring some paths with single relays (lower complexity) while other paths use multiple relays in series or parallel (higher reliability). This localized approach to redundancy ensures that safety-critical functions receive enhanced protection while non-critical functions maintain simplicity, resolving the contradiction between operational reliability and device complexity.

Inventive Principle:
Principle #3Local quality

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The double armature relay design enhances operational reliability, reduces installation space and costs, and ensures all switching paths are safe, providing improved safety and reliability in fail-safe shutdowns, meeting stringent safety standards like SIL3 and PLe.

Implementation Method 1

a relay coil which is actuated by a control signal and which has a magnetic coupling to the armature

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentEP4336537A1Relay device and safety switching device having at least one relay device
Publication Date: 2024.03.13 PILZ GMBH & CO KG
  • EP4336537A1 patent drawingFigure 1
  • EP4336537A1 patent drawingFigure 2
  • EP4336537A1 patent drawingFigure 3

AI summary

The invention relates to a relay device (1) comprising: - a number of input terminals (2.1-2.4), - a number of output terminals (3.1-3.4), - a first relay (4) with a number n ≥ 2 positively guided and parallel normally open contacts (9.1, 9.3, 9.5, 9.7) which form a first normally open contact group and are movable from an open position to a closed position and vice versa by means of a first common armature (5), - a second relay (7) with a number m < n positively guided and parallel normally open contacts (11.1, 11.2) which are movable from an open position to a closed position and vice versa by means of a common armature (8), wherein the first relay (4) and the second relay (7) are electrically connected in series with each other between the input terminals (2.1-2.4) and the output terminals (3.1-3.1).4) are arranged such that the relay device (1) has several parallel switching paths (S1-S4), and wherein in a number of switching paths (S3, S4) corresponding to the number m of normally open contacts (11.1, 11.2) of the second relay (7), a normally open contact (9.5, 9.7) of the first relay (4) and a normally open contact (11.1, 11.2) of the second relay (7) are each electrically arranged in series, wherein the first relay (4) is designed as a double armature relay.