Rolling Block Restraint Connector Linkage Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current connectors for structural framing members, such as rolling block restraint (RBR) connectors, face issues with eccentric loading causing twisting forces, complex installation due to multiple threaded rods, and potential weakening of members when using pins through centroids, leading to misalignment and reliability concerns.
Innovation Solution
The use of fixed-length links with adjustable wedge shims and spacers to set the angle of member intersection, along with extended block shafts to maintain parallel orientation and alignment, and transverse clamping fasteners to resist lateral forces, forming a moment-resistant connection that is independent of member size and material.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple threaded rods are used for linkage, then the connection can be adjusted, but the installation becomes complex and difficult to properly adjust
Solution Approach 1:
The linkage assembly is divided into separate components: a linkage body with pre-drilled holes and separate threaded rods. This segmentation allows for simplified assembly where workers only need to insert and secure the threaded rods through the predefined holes, rather than dealing with complex multi-rod adjustments simultaneously.
Solution Approach 2:
The linkage body acts as an intermediary component that pre-positions and aligns multiple threaded rods. By providing a central structure with predetermined hole locations, it mediates the alignment process and simplifies the adjustment procedure for connecting shafts.
2Strength
If a pin through the centroid is used to fix members, then vertical support is provided, but members are weakened and it is difficult to erect
Solution Approach 1:
The linkage system extracts the vertical support function from a single centroidal pin and distributes it across multiple connection points through the linkage body. This removes the need for a large centroidal hole while maintaining vertical support capability through distributed load paths.
Solution Approach 2:
The solution moves from a single-point (centroidal pin) to a distributed multi-point connection system. By adding dimensional distribution across multiple holes and linkage connection points, the system provides vertical support without requiring a large central opening that would weaken the member.
3Adaptability or versatility
If shafts are offset from each other, then the connection can accommodate member geometry, but twisting forces occur and misalignment happens
Solution Approach 1:
The linkage body is designed with asymmetric hole patterns that can accommodate offset shaft positions. The holes are strategically positioned to match the specific geometric requirements of the connected members, allowing asymmetric shaft arrangements while maintaining proper load paths and alignment.
Solution Approach 2:
The linkage body is pre-configured with holes positioned to anticipate and compensate for shaft offsets. By performing the alignment calculation and hole positioning in advance during manufacturing, the system eliminates field alignment issues and prevents twisting forces that would occur with improper offset accommodation.
Data Source
AI summary
A rolling block restraint connector for forming a moment resisting connection at a joint intersection between a continuous first structural member and at least a first continuous second structural member that intersects the continuous first structural member is shown. The connector includes a first restraint assembly including (i) a first block, (ii) a second block, and (iii) a first shaft that passes through channels of the first block and the second block, a second restraint assembly including (i) a third block, (ii) a fourth block, and (iii) a second shaft that passes through channels of the third block and the fourth block, a first linkage that couples the first restraint assembly with the second restraint assembly, and a second linkage that couples the first restraint assembly with the second restraint assembly, wherein the first shaft and the second shaft each pass through the first linkage and the second linkage.