Telescopic Crane Boom With Fewer Sides in Distal Extensions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing telescopic booms face challenges in achieving high extensibility and bending strength, particularly in the last extensions, due to the complexity of manufacturing sections with a large number of sides and the use of high-strength materials, which complicates the production of a large number of extensions.
Innovation Solution
The telescopic boom design incorporates a polygonal profile with decreasing sides in consecutive extensions, specifically a decagonal to hexagonal transition in the penultimate and last extensions, and uses skids with complementary surfaces for sliding coupling, allowing for a large number of extensions while maintaining high bending strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the number of extensions in the telescopic boom is increased to enhance versatility and extension capacity, then the extensibility and versatility of the crane is improved, but the bending strength of the distal extensions is reduced due to the reduced cross-section and manufacturing complexity
Solution Approach 1:
The patent applies different polygonal profile configurations to different extensions along the telescopic boom. Proximal extensions have a first polygonal profile with a larger number of sides (e.g., decagonal), while distal extensions have a second polygonal profile with a smaller number of sides (e.g., hexagonal). This local differentiation allows each extension to be optimized for its specific position: proximal extensions benefit from higher bending resistance due to more sides, while distal extensions maintain adequate strength with fewer sides and reduced manufacturing complexity.
2Strength
If high-strength materials and increased thickness are used to achieve desired bending strength, then the strength and load-bearing capacity are improved, but the weight of the telescopic boom increases
Solution Approach 1:
The patent optimizes the thickness and material distribution locally across different extensions. By reducing the number of sides in distal extensions, the required thickness for achieving adequate bending strength is reduced compared to uniform thick-walled proximal extensions. This localized optimization reduces the overall weight of the telescopic boom while maintaining the necessary strength through strategic material distribution and profile differentiation.
3Strength
If the number of sides in the polygonal profile is increased to enhance bending strength, then the resistance to bending is improved, but the manufacturing complexity and technological difficulty increase significantly
Solution Approach 1:
The patent strategically distributes the manufacturing complexity across different extensions. Proximal extensions, which have better access to manufacturing equipment and support structures, are produced with complex multi-sided polygonal profiles (e.g., decagonal) to maximize bending strength. Distal extensions, which are more difficult to manufacture due to their remote position and reduced cross-section, use simpler profiles with fewer sides (e.g., hexagonal). This local differentiation resolves the contradiction by matching manufacturing capability with structural requirements at each position.
Data Source
Figure 1~2
Figure 3~4
AI summary
The present invention relates to a telescopic boom (10) of a crane (1), extending along a longitudinal development direction (L) between a proximal end (11) and a distal end (12), and comprising a plurality of extensions (14', 14", ..., 14X), telescopically arranged inside each other and movable in translation with respect to each other along said longitudinal development direction (L), wherein each of said extensions (14', 14", ..., 14X) has, in a cross-section transversal to the longitudinal development direction (L), a polygonal profile, wherein, in at least one pair of consecutive extensions (14IX, 14X) of said plurality of extensions (14', 14", ..., 14X), the polygonal profile of the innermost extension (14X) of the pair of consecutive extensions has a number of sides less than the number of sides of the polygonal profile of the outermost extension (14IX) of the pair of consecutive extensions. The present invention also relates to a crane (1) comprising said telescopic boom (10).