Protective Cap for Concrete Screw Anchors

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing assemblies for structural elements in concrete structures face issues with screw connections becoming damaged due to deformations and forces, leading to corrosion and making it difficult to loosen the screw connection over time, especially when the protective cap introduces forces into the screw connection rather than the anchoring element.

Innovation Solution

The assembly features a protective cap with an internal lip for self-clamping and made from a deformable material, such as plastic, which absorbs transverse forces and deformations, ensuring the screw connection remains detachable by directing forces into the anchoring element and preventing corrosion, with anti-rotation devices to secure the cap in place.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a protective cap with large cross-sectional dimensions is used to protect the screw connection, then the screw connection is protected from corrosion and concrete penetration, but deformations and forces are introduced into the screw connection which can damage it

Engineering Contradiction:
Improveprotection from corrosionVSAvoidscrew connection integrity
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The protective cap is made from a deformable material that can flex and deform under transverse loads, allowing it to absorb forces without transmitting them to the screw connection. The cap's flexibility enables it to yield when concrete components deform, preventing force transmission to the anchored component while maintaining corrosion protection.

Inventive Principle:
Principle #30Flexible shells and thin films

Solution Approach 2:

The material properties of the protective cap are specifically selected to be more easily deformable than the concrete component. This parameter change in material stiffness allows the cap to deform preferentially under load, absorbing transverse forces through its own deformation rather than transmitting them to the screw connection.

Inventive Principle:
Principle #35Parameter changes

2Strength

If the protective cap is made rigid to maintain structural integrity, then it provides better protection, but it cannot absorb deformations and transmits forces to the screw connection

Engineering Contradiction:
Improveprotective cap integrityVSAvoidtransverse force transmission
Core Design Contradiction:
StrengthVSForce

Solution Approach 1:

The protective cap employs a flexible deformable material that maintains sufficient structural integrity to protect the screw connection while simultaneously absorbing transverse deformations through its own flexing, preventing force transmission to the anchored component.

Inventive Principle:
Principle #30Flexible shells and thin films

3Strength

If the protective cap is made from a deformable material to absorb transverse forces, then the screw connection is protected from damage, but the cap itself may detach or rotate

Engineering Contradiction:
Improvescrew connection protectionVSAvoidprotective cap stability
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

Anti-rotation devices are incorporated into the protective cap design before installation to prevent the cap from rotating or detaching. These devices ensure the cap remains stable and properly positioned while still maintaining its deformability to absorb transverse forces.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The anti-rotation devices act as intermediary elements between the protective cap and the anchored component, providing rotational stability without compromising the cap's ability to deform and absorb transverse forces. These devices mediate between the need for stability and the need for flexibility.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 effectively absorbs transverse forces in the anchoring element, preventing damage to the screw connection, ensuring it remains detachable and secure against corrosion, even after long-term use, while allowing for easy loosening and tightening of the screw connection.

Implementation Method 1

The protective cap is made from a material that is more easily deformable compared to the concrete of the concrete component and/or is shaped in such a way that, in the installed state, it yields to deformations and/or forces acting transversely to the axis of the screw connection

Methodology Applied
Scientific EffectDeformation: Deformation

Data Source

PatentEP3191655B1Assembly comprising a component
Publication Date: 2018.10.10 MAURER SOHNE ENGINEEERING GMBH & CO KG
  • EP3191655B1 patent drawingFigure 1
  • EP3191655B1 patent drawingFigure 2~3
  • EP3191655B1 patent drawingFigure 4

AI summary

The invention generally relates to an assembly (1) comprising a component (2) and an anchor plate (4) which can be at least partly concreted into a concrete component (3). The anchor plate (4) has at least one anchoring element which can be concreted into the concrete component (3) in order to transfer transverse forces (5). Furthermore, the anchor plate (4) is releasably connected to the component (2) by means of at least one screw connection (6), and the screw connection (6) comprises at least one screw (7) and a nut (8) with a protective cap (9). The invention is characterized in that the protective cap (9) is designed as a cap which can be plugged onto the nut (8) and concreted into the concrete. The outside (10) of the protective cap (9) has an outer anti-rotation element (11) and the inside (12) has an inner anti-rotation element (13).