Innovative solution for tractor door hinge problems

1 min read

A new tractor has been designed with a very large (1.30m) glass door and, since the aesthetics of the entire machine - especially the door parts - are critical, attention has been given to the door hinge, says Barry George, Pinet.

"The specifications from the manufacturer included being able to open the tractor door at 40º, ultra-violet resistance, withstanding of temperatures from -30ºC to +80ºC, resistance to high-pressure vehicle wash, meeting the salt spray test to 400 hours, and resisting 60,000 cycles (opening and closing). "Pinet's solution was a design a rolled knuckle hinge to a thickness of 4mm thus achieving a good mechanical resistance for a reasonable price. Knowing that the appearance of a rolled knuckle hinge sometimes is considered to be poor, a special plastic cover was designed to provide a fine looking aspect." One of the main issues was to develop the hinge with a limited opening angle - this function had to be integrated in the hinge itself without auxiliary components. The solution was to design the component with a stop integrated inside. "The stop limits the opening at 40º in use but the door needs to be opened to 45º in the assembly chain in order to accommodate the mounting of a gas spring. This solution has allowed the manufacturer to position the gas spring very easily." Pinet's solution has been to combine zinc-plated steel and plastic materials which, reports Barry George, "appears to be the best compromise between aesthetics, price, and durability." Pinet will be exhibiting at the Fastening & Assembly Solutions Show, National Motorcycle Museum, 23 October.