Elevator Threshold Angle Bracket Locking Plate Against Slippage

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Solution Overview

Problem

Existing elevator shaft door sill angle brackets experience slippage due to low friction, leading to reduced or eliminated engagement of the door leaf in the guide device, necessitating a solution for secure positioning and easy assembly.

Innovation Solution

A safety device comprising a securing plate with a perforated plate and connecting link, featuring offset toothing and alternative receptacles, allows for precise alignment and positive fit with the angle bracket, preventing slippage by providing multiple adjustment options and increased contact points for force transmission.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the angle bracket is held by friction through screw connection, then the installation is simple, but the positioning accuracy deteriorates due to slippage

Engineering Contradiction:
Improveinstallation simplicityVSAvoidpositioning accuracy
Core Design Contradiction:
Ease of operationVSManufacturing precision

Solution Approach 1:

A locking plate is introduced as an intermediary component between the angle bracket and the wall. The locking plate features a toothing structure that engages with corresponding teeth on the angle bracket, creating a positive mechanical lock that prevents slippage while maintaining the simplicity of the overall installation process.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The connection system is segmented into multiple functional components: the angle bracket, the locking plate with toothing, and the screw connection. This segmentation allows each component to perform its specific function - the angle bracket provides mounting, the toothing provides anti-slip positioning, and the screws provide secure attachment.

Inventive Principle:
Principle #1Segmentation

2Adaptability or versatility

If the screw connection is located in a slotted hole to compensate for tolerances, then the adaptability improves, but the reliability deteriorates due to bracket slippage

Engineering Contradiction:
Improvetolerance compensationVSAvoidconnection reliability
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The locking plate with toothing acts as a mediator between the slotted hole and the screw connection. The toothing structure provides positive engagement that prevents the angle bracket from slipping within the slotted hole, while the slotted hole maintains its ability to compensate for tolerance variations in the mounting process.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Manufacturing precision

If a locking device with toothing is introduced, then the positioning precision improves, but the device complexity increases

Engineering Contradiction:
Improvepositioning precisionVSAvoidstructure complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The toothing structure is implemented locally on the locking plate rather than throughout the entire assembly. This localized approach provides the necessary positioning precision at the critical interface between the locking plate and the angle bracket, while keeping the rest of the structure simple and easy to manufacture.

Inventive Principle:
Principle #3Local quality

4Ease of operation

If multiple receptacles with different center offsets are provided, then the ease of operation improves for retrofitting, but the manufacturing precision requirements increase

Engineering Contradiction:
Improveretrofitting easeVSAvoidreceptacle positioning precision
Core Design Contradiction:
Ease of operationVSManufacturing precision

Solution Approach 1:

Multiple receptacles with different center offsets are pre-positioned on the locking plate during manufacturing. This preliminary action allows installers to easily select and align the appropriate receptacle with existing screw holes during retrofitting, eliminating the need for complex measurements or modifications while maintaining adequate positioning precision.

Inventive Principle:
Principle #10Preliminary action

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 solution ensures high safety and precision in positioning the angle bracket, preventing slippage and maintaining effective engagement of the door leaf, while allowing for simple and adjustable retrofitting of existing systems.

Implementation Method 1

The toothing of the perforated plate (114) and cam (112) engage to one another in a positive fit

Methodology Applied
Scientific EffectMechanical interlocking: Gear

Implementation Method 2

The angle brackets can be held and positioned on the wall by friction, i.e., in particular by friction due to a tensile force from the screw connection

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP4003893B1Securing device for securing a position of an angle bracket of a shaft door threshold of an elevator shaft, angle bracket equipped with same and securing plate, and method for retrofitting such a securing plate
Publication Date: 2023.04.12 INVENTIO AG
  • EP4003893B1 patent drawingFigure 1
  • EP4003893B1 patent drawingFigure 2a~2b
  • EP4003893B1 patent drawingFigure 3a~3b

AI summary

The present invention relates to a securing device (102) for securing a position of an angle bracket (108) of a shaft-door threshold (100) of a lift shaft, to an angle bracket (108) and a securing plate (118) having such a securing device (102), and also to a method for retrofitting such a securing plate (118), wherein the securing device (102) has a slotted guide track (112), which is oriented in a direction of action (116), and a perforated plate (114), which can be arranged in the slotted guide track (112) and has a mount (208), which acts in the direction of action (116) and is intended for a screw connection (110) of the angle bracket (108), wherein the perforated plate (114) is shorter than the slotted guide track (112), as seen in the direction of action (116), and the slotted guide track (112) and also the perforated plate (114) each have at least one toothing formation (200), which is oriented in the direction of action (116), wherein the perforated plate (114) can be fixed in the slotted guide track (112) by a form fit between the toothing formations (200).