Tent Frame Guide Cams for Transverse Limb Pivoting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing tent frame constructions require significant strength and complexity to pivot hub parts relative to each other for erection, leading to expensive and cumbersome assembly processes.
Innovation Solution
A tent frame design featuring guide cams with ball and socket joints for the second set of pivots, allowing limbs to pivot transversely while maintaining fixed pivot axes, facilitating simpler and more cost-effective construction, easy erection, and even distribution of sheet material support.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If two parts of the hub are pivoted relative to one another to erect the tent, then the tent can be assembled, but considerable force is required and the construction becomes complex and expensive
Solution Approach 1:
The patent extracts the complex relative pivoting mechanism between two hub parts and replaces it with a simpler single-part hub design. The guide cams are integrated directly into the hub structure, eliminating the need for separate hub parts that must be pivoted relative to each other. This extraction of the complicating mechanism resolves the contradiction by maintaining ease of operation while significantly reducing device complexity.
Solution Approach 2:
Instead of having two hub parts pivot relative to each other to achieve erection, the patent inverts the approach by using guide cams that guide the limbs directly into their erected positions through controlled pivoting about fixed axes. The inversion transforms a complex multi-part pivoting system into a simpler single-part system with guided motion, resolving the contradiction between ease of operation and device complexity.
2Ease of manufacture
If guide cams are provided for limbs with ball and socket joints, then assembly is simplified and cost is reduced, but the mechanism for controlling limb movement must be effective
Solution Approach 1:
The guide cams act as intermediary elements between the ball and socket joints and the hub structure. These cams provide the necessary guidance and control for limb movement without requiring complex mechanisms. The intermediary guide cams translate the simple ball and socket joint motion into the precise arcuate paths needed for proper tent erection, resolving the contradiction by maintaining manufacturing simplicity while ensuring mechanism reliability through the mediating cam surfaces.
Solution Approach 2:
The guide cams utilize curved surfaces to guide the limbs through their required motion paths. The cam surfaces are shaped to provide the necessary arcuate movement guidance, allowing simple ball and socket joints to achieve the complex coordinated motion needed for tent erection. This use of curvature resolves the contradiction by maintaining manufacturing simplicity through smooth cam surfaces while ensuring mechanism reliability through geometric guidance.
3Stability of the object's composition
If limbs are pivoted about fixed pivot axes, then the pivot positions remain stable, but the limbs need guidance to achieve proper splaying and tensioning
Solution Approach 1:
The guide cams are designed to automatically guide the limbs through their required motion paths as they pivot about their fixed axes. The cam surfaces self-adjust to provide the necessary guidance without requiring external control mechanisms. This self-service approach resolves the contradiction by maintaining pivot axis stability while achieving easy limb deployment through the self-guiding cam mechanism.
Solution Approach 2:
The guide cams are pre-formed with the specific curved surfaces needed to guide limb movement. Before the tent is assembled, the cam geometry is already configured to provide the exact guidance needed for proper limb splaying and tensioning. This preliminary preparation resolves the contradiction by maintaining stable fixed pivot axes while enabling easy limb deployment through pre-configured geometric guidance.
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 design enables straightforward assembly and efficient deployment of the tent, maintaining sheet material tension evenly across the dome and allowing for speedy erection and collapse without removing the fabric.
Implementation Method 1
respective ends of at least two of the said plurality of limbs are secured to the hub by way of respective pivots, constituting a second set of pivots, enabling the said at least two of the said plurality of limbs to be pivoted about respective axes which are transverse, or have a component which is transverse, of the pivot axes of the said first set of pivots
Implementation Method 2
the hub is provided with respective guide cams for at least two limbs attached to the hub by way of ball and socket joints constituting or being included in the said second set of pivots
Data Source
Figure 1
Figure 2
Figure 3a~7b
AI summary
A tent frame (10) comprising a hub (12) from which extend a plurality of limbs (14,15), respective ends of some of which are secured to the hub (12) by way of respective pivots (16), constituting a first set of pivots, having respective pivot axes which are generally parallel to one another. Respective ends of at least two (15) of the said plurality of limbs (14,15) are secured to the hub (12) by way of respective pivots (24), constituting a second set of pivots, enabling the said at least two (15) of the said plurality of limbs (14,15) to be pivoted about axes which are generally transverse of the pivot axes of the said first set of pivots (16). The pivots (16,24) of the first and second set of pivots are fixed in position relative to one another even when the limbs (14,15) are pivoted about their respective pivots (16,24) whilst the frame (10) is unfolded into an erect condition and whilst it is folded for stowage.