What Is a Round Belt?
A round belt is a belt with a circular cross-section used in combination with pulleys to transmit rotational power through friction, similar to flat belts and V-belts.
- Most round belts are made of polyurethane and are used to transmit the driving force of motors in processing machines and conveyors.
They are also used for driving belts in three-dimensional layouts (e.g., where each axis is in a twisting position) because there are no restrictions on the surface to which frictional force is transmitted, and no matter which direction the belt contacts the pulleys, it can be driven.
Uses of Round Belts
Compared to other belts such as V-belts and timing belts, round belts can be used to construct a power transmission system at a lower cost due to their simple cross-sectional shape. Also, they do not require a tension adjustment mechanism because of the belt’s elasticity.
Therefore, round belts are used in cost-saving equipment, when the assembly accuracy of the distance between shafts cannot be guaranteed, and when accurate synchronization of rotation speeds is not required.
Round belts are also used for power transmission between shafts arranged in three dimensions or on the same axis, as the belt does not need to be arranged in a straight line.
Characteristics of Round Belts
Like flat belts and V-belts, round belts transmit rotational power only through friction, so slippage occurs when a load exceeds the static frictional force on the contact surface with the pulleys.
This slippage is similar to that of a torque limiter, which shuts off power for safety reasons when a certain amount of torque is applied.
On the other hand, since belt slippage causes a deviation in rotational speed between shafts, a transmission mechanism is needed to guarantee synchronization of rotational speed. For example, a timing belt is used in machines that require precise control of rotational speed and position. One advantage of round belts over other belts is that joints can be easily made.
In principle, belt lengths for V-belts and other belts are determined at the time of manufacture, and different belt lengths must be prepared for design changes. Round belts, on the other hand, can be joined with quick-melt joints, where the cross-sections are butt-welded together by heat, and the joints are relatively strong, making design changes and maintenance much easier.