Switch Cabinet Locking Device with Rotating Tab

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing locking devices for switch cabinet doors are not adequately designed for safety, as they can be easily accessed from the outside, even by untrained operators, and loose parts can fall inside, compromising electrotechnical safety.

Innovation Solution

A locking device with a swivel bolt and pawl mechanism, where the locking tab is rotatably held in a bearing, blocking access in operating and test positions but allowing access in the disconnected position, using an auxiliary release tool from the outside, and featuring a magnetic or screw-based attachment that is not visible from the outside.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a locking device with a swivel bolt and pawl mechanism is used, then access to the switch cabinet is blocked in operating and test positions, but the locking device can be easily accessed and manipulated from the outside

Engineering Contradiction:
Improveaccess restrictionVSAvoidexternal accessibility
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The bearing is integrated into the door structure in such a way that it is hidden within the door's internal geometry. The locking tab rotates within the bearing that is concealed inside the door, making the entire locking mechanism invisible from the outside. This nesting approach prevents external manipulation while maintaining the locking function.

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The control bolt acts as an intermediary element that transmits the locking state from the circuit breaker mechanism to the swivel bolt. When the circuit breaker is in operating or test positions, the control bolt engages with the swivel bolt's control contour to prevent its rotation, thereby blocking access without requiring direct external interaction with the locking components.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If the locking tab is held in a fixed door-secured position, then access is blocked, but loose parts can fall inside the control cabinet

Engineering Contradiction:
Improveaccess blockingVSAvoidloose parts falling inside
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The locking tab is designed to be dynamic rather than fixed. It can rotate between a door-secured position (blocking access) and a door-release position (allowing access). The bearing enables this rotation while keeping the tab concealed within the door structure, preventing loose parts from falling inside while maintaining access control functionality.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The swivel bolt, due to its own weight, automatically assumes a horizontal position in the door-securing position. This self-positioning mechanism ensures that the locking mechanism returns to the secure state without requiring additional components or active control, while the concealed bearing prevents loose parts from detaching.

Inventive Principle:
Principle #25Self-service

3Reliability

If the attachment of the locking tab is made invisible from the outside, then safety is improved, but the mechanism becomes more complex

Engineering Contradiction:
ImprovesecurityVSAvoidattachment mechanism
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The bearing that holds the locking tab is merged with the door structure itself. Instead of being a separate visible component, the bearing is integrated into the door's internal geometry, combining the functions of support, rotation, and concealment into a single integrated structure. This reduces the number of separate parts while achieving the security goal.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The locking mechanism is moved from the external surface dimension to the internal three-dimensional space of the door. The bearing and locking tab rotation occur within the internal volume of the door structure, utilizing the third dimension to hide the mechanism while maintaining its functional effectiveness.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

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

Enhances safety by ensuring access is restricted in operational and test positions but can be released securely in the disconnected position, preventing unauthorized access and reducing the risk of loose parts entering the cabinet.

Implementation Method 1

the swivel bolt being in the door securing position by its own weight, preferably is horizontal

Methodology Applied
Scientific EffectGravity: Gravitation

Implementation Method 2

A switch cabinet door (14) and frame (14') for a switch cabinet with a locking device... featuring a magnetic or screw-based attachment

Methodology Applied
Scientific EffectMagnetic attraction: Magnetism

Data Source

PatentEP2586110B1Locking device for a switch cabinet door
Publication Date: 2015.01.28 EATON ELECTRICAL IP
  • EP2586110B1 patent drawingFigure 1~2
  • EP2586110B1 patent drawingFigure 3~4C
  • EP2586110B1 patent drawingFigure 5A~7B

AI summary

The invention relates to a locking device for a switch cabinet for a multi-pole electric power circuit breaker arranged in a switch cabinet on an extension unit such that it can be moved between an operating position, a test position and an isolated position. When an auxiliary release (20, 30) is actuated from the outside of the switch cabinet door (14), the securing unit permits access to the switch cabinet even in barred positions comprising the operating position (C) and test position (T). The securing unit comprises a pivoting bolt (20) provided with a latch (21), and a locking lug (30) which interlocks with the latch (21) and produces the bar to access. The auxiliary release consists in that the locking catch (30) is fixed in a position that can be changed from the outside of the switch cabinet door (14) by using an auxiliary release tool. The locking catch (30) is held such that it can rotate like a rocker. The locking catch (30) assumes the door-release position when actuated with the auxiliary release tool. After being actuated with the auxiliary release tool, the locking catch (30) rotates from the door-securing position into the door-release position as a result of its own weight.