V-beltA V-belt is a mechanical linkage that has an isosceles trapezoid cross sectional shape. V-belts tend to be made of rubber, neoprene and urethane synthetic materials. They are typically used in cars to power things such as the fan they are used for this as they are easy to install and therefore are easy to replace, they require no lubrication as they rely on friction to transmit power and if lubricated would not work correctly, they have a wide horsepower and speed range and they also dampen shock load however they are not recyclable meaning the are less environmentally friendly .
A V-belt has a bottom section also known as the compression section which is made from a tough rubber and exerts a wedging force V-belts against the pulley groove which increases adherence, they have a top section which is known as the tension/insulation section which has fibre cords imbedded in it that give the belt increased strength properties and they also have a protective cover which is elastic and is made of rubber impregnated fabric this protective cover is slip resistant and also heat resistant to protect the inner components of the belt.
Belt drives are used because if a system becomes blocked when using a chain or gear drive the whole power transmission system could be damaged whereas if a belt is used the belt is able to slip therefore reducing the risk of damage to the system. V-belts require maintenance this includes tensioning the belt as over time it will become slack.There are multiple types of V-belt these include:Classic V-beltsThese are the most common type of V-belt and are commonly used in agricultural and industrial applications. They have a fairly good temperature resistance which is 35 degrees Double sided V-beltsDouble sided V-belts are used when power transmission is needed on both sides of the belt. This type of belt is most commonly used in textile and industrial applications. The temperature resistance for a double sided V-belt is the same as that of a regular V-belt and so is the oil resistance.Cogged beltsThis kind of V-belt is used in applications where the pulley has a small diameter and spins at a high speed the temperature resistance for this belt is the same as the classic V-belt.. The slots help to reduce bending resistance and they also keep operation temperatures lower. These belts can be used as an alternative to a classic V-belt due to the fact they are more efficient and they last longer than standard V-belts.Automotive beltsThis type of belt is designed for the automotive industry they are very similar to the cogged belts as they are designed to work with small pulley diameters and high speeds. Fractional wrapped beltsFractional wrapped belts are designed to be used in low horsepower applications that require low maintenance. They are used in things like low HP diesel engines, pumps and processing machines.kevlar/aramid beltsThis type of belt is designed to work where resistance to oil, dirt, grease and moisture is required. They are most commonly used in things like lawnmowers but are also used in military applications. Despite being designed to resist oil and dirt they still have the same temperature range as the classic V-belt.Alternatives to a V-beltTwo alternatives I would suggest to a V-belt would be a notched (cogged) V-belt and a duplex chain. The notched V-belt is a suitable alternative as it keeps operation temperatures lower and also has notches to reduce bending resistance making them more efficient a notched V-belt can also be used in wet and oily conditions. The duplex chain however provides slip free power transmission, they can be easily shortened, they have a smaller wrap angle and are also less susceptible to temperature changes, they don’t deteriorate due to oil, grease, sunlight, or age, they are able to operate in wet conditions and they can also withstand chemicals. Due to chain being made of steel alloys means that it can be recycled. The bearing, bush and pin on a chain are case hardened. The properties of a chain make it a suitable alternative to a V-belt. Change gearsThe current gears on a lathe are spur gears. Spur gears are the most common types of gear. They have straight teeth and are mounted on a parallel shaft. The advantages of spur gears are they have a high power transmission efficiency, they are easy to install and are compact. The disadvantages of spur gears are that when they are operating they create a lot of noise and the teeth of the gear experience a lot of stress. Common materials for spur gears to be made of include bronze, steel alloys, cast iron and nylon. Spur gears are used as they are relatively easy to manufacture and are good for speed reduction, they are also fairly durable and easy to install. The gears are used to reduce or increase the speed of the leadscrew. AlternativesOne alternative to a spur gear would be a helical gear. Unlike a spur gear where the teeth are parallel to the axis of rotation the teeth on a helical gear aren’t instead they are angled this is so that the pressure is distributed gradually along the whole tooth rather than the pressure being put on the tooth all at once. Helical gears are able to run quieter and smoother than spur gears the reason they are able to run smoother and quieter is because the tooth gradually engages the other tooth because of the angle this means that there is less impact loading and therefore there is less stress on the teeth meaning that helical gears last longer however spur gears are more efficient. Helical gears can also transmit power either parallel or at a 90 degree angle Another alternative to a spur gear would be a worm gear. A worm gear doesn’t mesh like a spur gear instead it rotates more like a screw. The gear with the screw like appearance is the worm gear and the spur gear is known as the work wheel. Worm gears can be produced with an hourglass shape which increases the amount of contact between the worm gear and worm wheel. Because the teeth of the worm gear slide past the teeth of the worm wheel friction is created and therefore this friction needs to be reduced so the worm gear is usually made out of a hard material. Worm gears are quieter than spur gears. However a worm gear needs more regular lubrication than a spur gear and also requires a high viscosity lubricant with that is able to help overcome the sliding friction this friction also generates heat. They are also good for reducing speed and increasing torque however they are expensive and have a low power transmission efficiency. Worm gears are used in machines such as lifts where their auto locking feature is used as a braking system in the event of a failure. Worm gears are also used in security gates.BearingsTapered roller bearing notes:They have an inner ring and outer ring and have multiple tapered rollers.Both the inner and outer rings are also tapered like the rollers this creates a cone shapeThe angle that is formed by the line of contact between the rollers and the bearings outer casing determines the kind of load that the bearing is suited to the larger this angle the better the bearing can cope with thrust loads however it reduces the bearings capacity to cope with radial loadsThis kind of bearing are only able to accommodate axial thrust in one direction so manufacturers place paired rows of rollers into the bearing to accommodate for axial thrust in both directions