Table Underframe with Prestressed Reinforcing Web to Prevent Sagging
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Solution Overview
Problem
Existing table frames struggle to prevent deflection of large tabletops under load while maintaining a visually appealing, filigree design, as they need to balance flexural and torsional rigidity with aesthetic considerations.
Innovation Solution
A table frame design that incorporates a reinforcing web anchored to longitudinal members, prestressed by bending, which generates upward pressure against gravity, counteracting loads and maintaining a flat shape without significant yield, allowing for larger spans without sagging.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If larger furniture dimensions are used to provide sufficient resilience, then load-bearing capacity is improved, but the design becomes less filigree and visually appealing
Solution Approach 1:
The support structure is divided into multiple longitudinal members (at least two) that are spaced apart, with reinforcing webs anchored to these members. This segmentation allows the load-bearing function to be distributed across multiple elements rather than requiring a single large, bulky support structure.
Solution Approach 2:
The invention introduces reinforcing webs that extend in a direction transverse to the longitudinal members, creating a three-dimensional prestressed structure. By anchoring these webs and applying prestressing forces, the system gains additional structural rigidity without increasing the footprint or visual bulk of the support elements.
2Stability of the object's composition
If mechanical coupling elements are used to connect supporting elements, then structural rigidity is improved, but aesthetic appeal deteriorates due to visible fixtures
Solution Approach 1:
The reinforcing webs are integrated with the longitudinal members by being anchored directly to them, creating a unified structural system. The prestressing force is applied through this integrated system, eliminating the need for separate mechanical coupling elements that would be visible and aesthetically displeasing.
3Strength
If more supporting elements are provided to prevent deflection, then deflection resistance is improved, but legroom under the table is restricted
Solution Approach 1:
The reinforcing webs are prestressed before the tabletop is installed, creating pre-compression forces in the longitudinal members. This preliminary action of prestressing allows the structure to resist future deflection loads more effectively, reducing the need for additional supporting elements that would intrude into the legroom area.
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 prestressed frame effectively prevents undesirable sagging of tabletops over 3 meters in length, particularly with four legs, while allowing on-site reinforcement during assembly, simplifying production and maintaining a visually appealing appearance.
Implementation Method 1
the reinforcement web is pulled upwards on both ends opposite the anchor points and a bending stress is generated. The anchor points cause the reinforcement web to deflect downwards in the longitudinal direction and transfer the bending stress as an upward deflection to the side member, which is elastically deformed.
Implementation Method 2
using an artificial deformation of a reinforcing web anchored to a respective longitudinal member of the frame, this longitudinal member is prestressed under pressure
Data Source
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AI summary
Table frame comprising a frame (1) with longitudinal and transverse beams (5, 4) attached to one another, which form a support for at least one table top (3), and table legs (2), wherein the longitudinal beams (5) are prestressed in compression by at least one reinforcing web (10) anchored longitudinally to a longitudinal beam (5) and bent downwards in the longitudinal direction, the two ends (8) of which are fixed to the transverse beams (4) via tensile force supports (17), so that a tensile stress determined by the respective bending moment of the reinforcing web (10) can be introduced into the longitudinal beam (5).