Asymmetrical Silent Chain Link Plate Design for Strength
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional double-sided driving silent chains with symmetrical link plates face challenges in ensuring sufficient strength and wear resistance due to narrow plate width and small contact area with guide components, leading to reduced transmission life and performance.
Innovation Solution
The design features asymmetrical double-sided driving link plates with a shallower crotch on one side and a deeper crotch on the other, along with specific dimensions and curvature of teeth to enhance tensile and fatigue strength, and a larger contact area with guide components to reduce wear.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If symmetrical double-sided driving link plates are used, then the chain can engage with sprockets on both inner and outer sides, but the plate width at the crotch area becomes narrow resulting in insufficient tensile and fatigue strength
Solution Approach 1:
The link plate is designed with asymmetrical upper and lower parts where the crotch depth differs between sides. The first side has a shallower crotch while the second side has a deeper crotch, creating different plate widths at critical sections to optimize both strength and engagement characteristics for double-sided driving
Solution Approach 2:
Different regions of the link plate are given different geometric properties - the shallower crotch area on the first side provides greater plate width and higher strength, while the deeper crotch area on the second side provides optimized engagement geometry. Each local region is tailored to its specific functional requirements
2Ease of manufacture
If symmetrical link plates with same tooth edge portions are used, then manufacturing is simplified, but the contact area with guide components becomes very small leading to rapid wear
Solution Approach 1:
The tooth configurations on the upper and lower sides of the link plate are made asymmetrical. The first side has teeth with specific edge portions optimized for one type of engagement, while the second side has teeth with different edge portions optimized for contact with guide components, ensuring sufficient contact area and reduced wear
Solution Approach 2:
Different tooth geometries are applied to different sides of the link plate based on local functional requirements. The teeth on the second side are specifically designed with edge portions that provide adequate contact area with guide components, while teeth on the first side are optimized for sprocket engagement
3Ease of operation
If the crotch depth is increased to improve engagement, then the plate width decreases resulting in reduced strength
Solution Approach 1:
The crotch depths on the upper and lower sides of the link plate are made different. The shallower crotch on the first side maintains sufficient plate width for strength, while the deeper crotch on the second side optimizes engagement performance, resolving the trade-off between these two requirements
Data Source
AI summary
A silent chain using double-sided driving link plates having symmetrical upper and lower teeth has a problem that it is unable to assure a required risky sectional area of the plates because a width between upper and lower crotches is narrow. The invention provides a silent chain using double-sided driving link plates whose required risky sectional area is maintained by using link plate whose back side is undercut and whose upper and lower parts are unsymmetrical even though its front side has a shape of a normal link plate. A distance from a line connecting centers of pin holes to a bottom of an upper-side crotch is equal to or more than ½ of a diameter of the pin hole to assure the risky sectional area. Teeth of the back side are cut away to form a flat surface to assure a contact area with a shoe and others.