Just like conveyor belts, the origins and history of power transmission belts are lost in the mists of time. While we believe that the Babylonians and Assyrians used chains and cups for water-drawing machines, the earliest mention of a mechanical belt drive with a pulley machine is in a Chinese text from 15 BCE. This describes how it was set up to wind silk fibers onto bobbins for weavers’ shuttles. About a thousand years later, when the first reported mechanized spinning wheel was documented, again in China, it relied on a belt drive. I find this fascinating – because the textile industry is still home to numerous applications for power transmission belts today.
The belt drive has also been used in many other applications. We know that flat belts were frequently employed in the 19th and 20th centuries for power transmission in factories, as well as for logging, mining and farming applications, such as sawmills, conveyors and pumps.
Simple and efficient
Belts and pulleys offer the simplest and most efficient way to transmit power between shafts. Even today’s advanced computer-controlled machines rely on this attractive and proven solution.
Power transmission belts run smoothly and quietly, helping to protect machinery from overload and jamming, and shielding motors and bearings against load fluctuations. They need minimal maintenance, and are highly efficient (up to 98%).
Wide belts and large pulleys can deliver high power at high speeds – although these take up a considerable amount of space. This is why V-belts were later introduced, which are frequently used today for short-distance power transmission. On the other hand, V-belts are not as energy-efficient as flat power transmission belts and timing belts.
From leather to hemp to polyamide
As you’d expect, the materials used for power transmission belts have changed over the years. While in the past, flat belts were usually made of leather, in the mid-19th century they also used ropes made of cotton, hemp, flax, or even wire.
But power transmission with leather belts remained a popular solution for centuries. Even at the beginning of the 20th century, leather belts were the state-of-the art solution for efficient power transmission. You can see this in pictures that show, for example, a workshop with a main driving shaft on the ceiling, with milling machines, lathes, drilling machines and other equipment running off it, all driven by leather belts.
Today, most power transmission belts consist of elastomer covers combined with a belt body made of synthetic polymers. Habasit’s founder Fernand Habegger recognized the new opportunities provided by the excellent properties of polyamide (first discovered in 1935, and produced commercially from 1938), when he launched a new generation of power transmission belts and opened Habasit in 1946.
Power transmission belts have found many new and important uses today. And while they continue to play a leading role in modern machine design, they are less visible than in the past, as in many cases they are protected by the machine frame and perform their task ‘under cover.’ The following examples illustrate the capabilities of this outstanding machine element in different industries:
In the textile industry, power transmission belts and spindle tapes (a specially designed power transmission belt to drive a group of four spindles) are employed in yarn manufacturing and processing, e.g. on spinning machines. The fashion industry and manufacturers of technical fabrics demand high- and consistent yarn quality at the best possible price. The performance of the power transmission belt is crucial to meeting these expectations, so that the final customer (in other words: you) can benefit from a durable shirt that keeps its shape over its entire lifetime. What’s more, using the right belt type contributes to savings on energy and operational costs.
In letter sorting machines, power transmission belts drive the letter transport belts and are essential to achieving precise sorting that delivers the highest machine throughput with the lowest costs and energy consumption. With throughputs of up to 70,000 mail items (e.g. letters) every hour, the reliability of every machine part is a must.
Power transmission belts for punching machines, presses, etc., have a tough job because they have to transmit very high loads. They also have to absorb shocks, for example overloads, in order to protect other machine elements like motors and bearings.
In distribution and parcel sorting centers, power transmission belts drive the live rollers. Belt performance is decisive here for precise sorting with the highest machine throughput and the lowest costs and energy consumption. These belts make an important contribution to the fast and timely delivery of your online orders.
Do you need a power transmission belt?
From the past to the present to the future, power transmission belts will continue to play an important role in a huge range of industries and applications. If you’d like to know more about Habasit’s HabaDRIVE range of power transmission belts, please get in touch.