Mould Drum Tooth Profile for Fatigue-Resistant Torque Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Mould drums used in food product moulding experience fatigue cracks due to torque transfer stresses, particularly when extending the drum length, leading to reduced lifespan and increased risk of damage.
Innovation Solution
Implementing a meshing tooth profile on both the driven flange structure and the mould tube, eliminating the need for dowel holes and providing a more even load distribution, which enhances the durability and longevity of the porous mould tube.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If dowel pins are used to transfer torque from the driven flange structure to the mould tube, then torque transfer is achieved, but fatigue cracks occur at the dowel holes after extended use
Solution Approach 1:
The invention removes the dowel pins and dowel holes from the torque transfer mechanism. Instead of using discrete dowel elements that create stress concentration points, the torque is transferred directly through the meshing tooth profiles formed by the gear structure integrated into the mould tube and driven flange structure, eliminating the source of fatigue cracks.
Solution Approach 2:
The torque transfer interface is segmented into multiple meshing teeth around the circumference of the mould tube. This distributes the torque transfer across multiple contact points rather than concentrating it at discrete dowel locations, reducing stress at any single point and preventing fatigue crack initiation.
2Productivity
If the length of the drum is extended from conventional 700 mm or smaller to 1000 mm or longer, then productivity is improved, but additional torque causes accelerated fatigue and cracks
Solution Approach 1:
The torque transfer mechanism transitions from a point-based dowel connection to a distributed circumferential gear meshing system. By utilizing the circumferential dimension with multiple meshing teeth, the torque transfer is distributed around the entire perimeter of the mould tube, significantly reducing the stress burden on any single location even when the drum length is extended to 1000 mm or more.
3Ease of operation
If dowel holes are provided in the mould tube for accommodating dowels, then torque transfer is enabled, but the holes cause stress concentration and crack initiation
Solution Approach 1:
The harmful dowel holes that create stress concentration are completely removed from the design. Torque transfer is achieved through external meshing gear teeth on the mould tube surface, eliminating the need for holes penetrating the porous mould tube material and the associated stress concentration zones.
Solution Approach 2:
Instead of creating holes in the mould tube to insert dowels for torque transfer, the invention inverts the approach by forming protruding gear teeth on the mould tube that mesh with corresponding teeth on the driven flange structure. This external engagement method avoids penetrating the mould tube material entirely.
Data Source
AI summary
A mould drum, a system for moulding comprising a mould drum, a method for moulding, and a method for manufacturing a mould drum such that the mould drum includes a mould tube defining an outer circumferential surface with groups of multiple recessed mould cavities. The mould tube has a first mould tube head end. The mould drum includes a driven flange structure arranged against the first mould tube head end, which is adapted to be driven by a mould drum drive member to rotate the mould tube about a drum rotation axis. The driven flange structure is provided with a tooth profile, and the mould tube is provided with a meshing tooth profile, both tooth profiles meshing with each other and thereby being able to transfer torque from the driven flange structure to the mould tube.