C-Shaped Pulley Structure for Belt Wear and Axial Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing pulley devices for tensioning idlers or runner rollers suffer from early wear of belts and radial deformation under heavy loads, leading to inefficient belt support and potential axial movement during service use.
Innovation Solution
A pulley device with a bearing comprising a rotatable outer ring and a fixed inner ring, featuring C-shaped pulley parts with radial intermediate portions and through-holes for mechanical retention, providing increased rigidity and stability to prevent belt wear and deformation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If male and female overlapping parts are fastened together to form a cylindrical outer portion, then the pulley structure is formed, but an annular recess is created causing early belt wear
Solution Approach 1:
The pulley is divided into two separate C-shaped pulley parts that are mounted on opposite sides of the bearing, eliminating the need for overlapping parts and the resulting annular recess that causes belt wear. Each pulley part is a complete C-shape that contacts the belt without creating recesses.
Solution Approach 2:
Instead of forming the cylindrical outer portion by overlapping parts in the radial direction, the invention uses two C-shaped pulley parts mounted on opposite sides of the bearing in the axial direction, with their outer portions in axial abutment, thereby eliminating the harmful annular recess while maintaining structural integrity.
2Ease of operation
If the pulley is tightened to the outer ring of bearing, then the pulley is secured, but the pulley can still axially move during service use
Solution Approach 1:
The invention uses elastic deformation of the inner portions of the C-shaped pulley parts to create mechanical retention. The inner portions are configured to be deformed by an external tool inserted through outer through-holes, creating elastic retention forces that prevent axial movement while allowing for installation and disassembly.
Solution Approach 2:
The inner portions of the pulley parts are designed to change their deformation state during installation. An external tool applies force through the outer through-holes to deform the inner portions, creating mechanical retention that prevents axial movement during service use while maintaining ease of installation.
3Ease of operation
If the outer part is designed to contact the belt, then belt support is provided, but the outer part may be deformed radially inwards by bending under belt action
Solution Approach 1:
The pulley is segmented into two C-shaped parts with radial intermediate portions extending between the inner and outer cylindrical portions. This segmentation creates a more rigid structure that resists radial inward deformation while maintaining the belt contact function of the outer portions.
Solution Approach 2:
The pulley parts are formed as integral C-shaped structures combining the inner portion mounted on the bearing, the radial intermediate portion providing structural rigidity, and the outer portion contacting the belt. This composite structure prevents radial inward deformation while maintaining belt support function.
4Object-affected harmful factors
If damping ring is housed within a C-shaped pulley, then vibrations are dampened, but the pulley can still be deformed under heavy loads
Solution Approach 1:
The pulley is divided into two C-shaped pulley parts with robust radial intermediate portions that extend substantially radially between the inner and outer cylindrical portions. This segmented structure with intermediate portions provides inherent rigidity that prevents deformation under heavy loads, complementing the vibration damping function.
Data Source
AI summary
A pulley device for supporting a belt of a chain tensioning idler or a runner roller includes a bearing having an outer ring mounted for rotation relative to a coaxial inner ring and first and second C-shaped pulley parts mounted on the radially outer surface of the outer ring with their openings facing each other. The radially outer portion of the first and/or second pulley part includes at least one radial through opening, and a first portion of at least one of the pulley parts radially inward of the through opening is deformable from a first configuration in which the first pulley part is axially movable relative to the outer ring to a second configuration in which the first pulley part forms an interference fit with the outer ring or with the second pulley part. Also a method of connecting the pulley parts to the outer ring.