Safety Switch Door Release Unit Integration

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing safety switches for protective doors lack a straightforward mechanism for releasing the door, leading to spatial separation issues that create risks during special operating modes like setup or troubleshooting, and do not allow direct door release at the safety switch.

Innovation Solution

Incorporating a door release unit that can assume a locked or unlocked state, allowing or canceling the actuator blockage in the second position, enabling direct generation of a release signal at the safety switch without physical separation, using an electrical door release unit that determines release signals based on supplied variables, and employing transponders for secure and flexible door release management.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the safety switch is spatially separated from the protective door (as in remote safety switching devices), then the door release can be requested from a distance, but this creates risks during special operating modes like setup or troubleshooting and prevents quick intervention in case of malfunctions

Engineering Contradiction:
Improvedoor release operationVSAvoidsafety during special operating modes
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The patent combines the safety switch with the protective door assembly, integrating the door release unit directly into the safety switch housing. This merging eliminates the spatial separation between the safety switch and the protective door, allowing operators to quickly access and release the door during special operating modes while maintaining safety through integrated control logic that prevents unauthorized access during normal operation.

Inventive Principle:
Principle #5Merging (Combining)

2Reliability

If the actuator is blocked in the second position to prevent the protective door from opening, then safety is maintained, but the door cannot be opened even when needed for setup or troubleshooting

Engineering Contradiction:
Improvesafety during operationVSAvoidoperation in special modes
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent implements a dynamic blocking mechanism where the blocking element can be positioned in different states: blocked in the second position during normal operation to prevent door opening, and unblocked when a door release request is detected to allow door opening. This dynamic adjustment of the blocking state enables the system to adapt between safety-critical operation and special operating modes like setup or troubleshooting.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system uses feedback from the door release unit to control the blocking element. When the door release unit detects a release request (through buttons, switches, or other input elements), it sends a signal to the actuator to move the blocking element from the blocked to the unblocked position. This feedback mechanism ensures the door can be opened when needed while maintaining safety during normal operation.

Inventive Principle:
Principle #23Feedback

3Ease of operation

If a mechanical emergency release mechanism is used, then the door can be opened in emergencies, but mechanical contamination risks arise and the mechanism becomes more complex

Engineering Contradiction:
Improveemergency door releaseVSAvoidmechanical contamination
Core Design Contradiction:
Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The patent replaces mechanical emergency release mechanisms with an electrical/electronic door release unit. The release request is detected through electrical switches, buttons, or other input elements that trigger an electrical signal to the actuator, which then moves the blocking element. This substitution eliminates mechanical contamination risks associated with traditional mechanical emergency releases while maintaining the ability to quickly open the door in emergencies or during special operating modes.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentEP2352948B1Safety switch for creating a system release signal in dependence on the position of a movable guard door
Publication Date: 2016.05.04 PILZ GMBH & CO KG
  • EP2352948B1 patent drawingFigure 1
  • EP2352948B1 patent drawingFigure 2~3
  • EP2352948B1 patent drawingFigure 4

AI summary

The invention relates to a safety switch (16), wherein at least one part of the system (10) located in the danger zone can be operated upon the presence of the system release signal. The safety switch (16) exhibits a door part (17) and a frame part (18). Furthermore, the safety switch (16) exhibits an actuator (56) that can be adjusted between a first and a second position, a recess (100) into which the actuator (56) can engage in the second position, and a blocking element (104) that is designed to block the actuator (56) in the second position. The safety switch (16) furthermore has a first position sensor (114) that is designed to clearly detect at least one of the positions of the actuator (56) in order to create the system release signal in dependence on said at least one position. The safety switch (16) furthermore comprises a door release unit (130) that can capture a locking state and an unlocking state, wherein a blockade of the actuator (56) by the blocking element (104) of the second position is not permitted or raised in the locking state.