Belt and Pulley Prototyping Solution
| AS9100D | ISO9001 | ISO14001 | IATF 16949
About Belt and Pulley
Pulley is a mechanical component used to transfer motion from shaft to belt or rope and vice versa. Pulley and belts are the easiest and common mediums of power transmission.
The belt and pulley solution for mechanical power transmission has been around for several centuries. The belt technology has become very sophisticated to include a variety of high-strength fibers in the belting to increase the load capacity of the belt. A belt and pulley solution can be very efficient for a transmission system.
Pulleys can be seen in more than one form as they serve various purposes in the industrial world. A pulley is a wheel on an axle or shaft designed to support movement and change the direction of a belt or taut cable. The device helps in power transmission using a cable or belt.
In a belt and pulley system, a belt runs along a pulley’s groove so that the power can be transferred either from one pulley to another or from the pulley directly to the application that requires power.
Types of Belt on Transmission System
The type of belt to use depends on the type of application:
- torque to be transmitted
- rotational speed
- centre distance
- reduction ratio
- temperature and lubrication conditions
The most common type of gear is used in the mechanical system. These gears have equally spaced triangular-shaped teeth around the circumference of a circle. It is featured with high efficiency, high power at high speed, long service life, silent operation, considerable center distance, etc.
At the same level of tension, V belts transmit higher power than flat belts. They are used, for example, in variable-speed drives. They offer the best combinations of traction, speed, bearing load and service life.
This kind of belt is ribbed lengthwise, significantly increasing the contact surface between the pulley and the belt. Its one-piece structure allows for homogeneous distribution of the belt tension on the pulley’s contact surface. It is featured with long service life and reliability, stable tension, silent transmission, large transmission ratio, etc.
Synchronous Slotted Belt
This kind of belt is slotted, used to drive camshafts or for the secondary transmission of some motorcycles. It is also widely used on many industrial or agricultural machines. It is an essential solution to avoid any phase shifts, ensuring the synchronization of the system and the transmission of movement without slipping.
Choose the Right Pulley
Pulley is also used to guide a cable or exert a force, and it changes the direction of force, making pulling down easier than lifting. These kinds of pulley may be called “Sheave”. Well, a drive element of a pulley system can be rope, cable, belt, or chain.
Below are things to consider while selecting a drive and pulley for a device:
- The source of energy used in transmitting energy
- Center distance between the shaft and pulley
- The speed of the driver and driven pulley
- Power transmitted between the system
- The layout of shafts
- The flexibility of the belt
- Reliability and durability of the belt
- How much high tensile stress can it withstand
- Low weight per unit length
- Resistance to wear and fatigue
- High coefficiency of friction between belt and pulley
- Peak temperature that can be resisted.
Open belt drive (pulley)
The shafts rotate in the same direction. The direction of rotation is the same as the driven pulley. The shafts are arranged in a parallel direction.
Crossed belt drive (pulley)
In crossed types of pulleys, the transmitted power is more, but it cannot run faster. It may cause wear and tear to the belt. The shaft rotates opposite the pulley. In order to eliminate wear and tear in these pulley types, more distance should be placed between the pulley, and then it should be run at low speed.
Fast and loose cone pulley
In these types of pulleys, there are two pulleys. The first one is faster than the other. The fast pulley is mounted on a shaft with a keyed joint, whereas the loose pulley runs freely. This loose pulley does not transmit any power. These types of pulleys are suitable for multiple machines that derive power from a single source.
Stepped cone pulley
The stepped cone pulley is also known as the speed cone. In these pulley types, there are more than one pulleys of different diameters attached to be adjacent to each other. A stepped cone pulley is used in applications that require changing gear or where the speed of the driven shaft changes frequently like machines. The same belt is used for different speeds attained.
A jockey pulley is used in a steering section of a system. It’s similar to an idle pulley used to increase the angle of contact in a one belt drive. The function of a jockey pulley is to increase the angle of contact of a belt. This is to help the belt tension increase and offer a high-velocity ratio to the drive.
All the above-explained pulleys are used to transmit rotational motion in one way or the other. Some other types of pulley include:
Complex pulley system
A complex pulley system has a block and tackle system that contains two or more individual drums. Each of these drums has two or more wheels that rotate on the same axle. A rope is looped back and forth between the drums and pulley to help it multiply to accomplish the operations. The complex pulley system is used to move a hefty load.
A compound pulley has both fixed and moveable pulleys, making the load feel lighter. With this, the direction of the force can be easily changed, making the system suitable for moving heavy loads. Sometimes, more motion is required for the work to be appropriately done. It is also called a combination pulley system. It’s designed to make heavier loads be lifted with less force. It is often used on a construction site to lift heavy objects like concrete and steel.
The moveable types of pulley consist of a drum that moves while moving an object. There is no change in the direction of the force, but the object still feels much lighter than it supposes to. A moveable pulley moves more freely. It’s often seen in an elevator.