Blind chain pulley and servo bracket

thingiverse

This is a custom-designed pulley tailored to fit snugly around a chain featuring rounded metal protrusions. I've come across several similar pulleys, but none of them met my specific requirements for my blind chain system. The centre-to-centre spacing between the spheres on my chain measures approximately 4.2 mm, and the gap between adjacent spheres is roughly 1.1 mm. Each sphere has a diameter of about 3.2 mm. The pulley seamlessly fits onto the shaft of a micro servo (specifically, a 12g model shown here), which will be used in a home automation project. Additionally, I've included a bracket that allows for both vertical adjustment of the servo's position and the bracket itself to slide up and down. This setup enables precise tensioning of the chain, ensuring it fits comfortably within the pulley without causing excessive strain on the servo. To facilitate easy installation and removal of the device, I've mounted everything onto a basic support structure.