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Design and Selection of Machine Elements – Gears, Pulleys, and Belts

Introduction 

Gears are the most basic part of mechanics. It is an important segment in physics. Most of the equipment, gadgets, and mechanical tools are based on the system of gears, pulleys, and belts. Gears, pulleys, and belts are essential tools in agricultural engineering and their practical applications. It is also often circular and has lots of teeth. These teeth are employed to lock into other gears or mechanical tools. Mostly, these teeth are called cogs. Gear is used to transform torque. Gears also enhance speed. Gears and pulleys together create essential equipment which is used the maintain equilibrium and efficiency.

Gears

Gears and pulleys are used in conjunction with mechanical apparatus. A gear is a machine part. Gears and levers follow the same analogous principle. Gears are simple machines. A gear has multiple uses in various fields. Gears are mainly used for the following reasons:

  •  To control and transform torque
  • To change the direction of speed
  • To change the direction of power
  • To control the rotational forces

A gear train happens when several gears are placed sequentially. The gear system and pulleys and belts systems are very similar. Torque is a type of force in physics. In practical application, torque is the rotational force, equivalent to linear force. It is represented as T = r F sin Ø. 

Key Characteristics of Gears

Gears are also known as mesh. These mechanisms transmit specific energy from one object to the other. Mechanical energy is the type of energy that is transmitted. Movements which are used in this case are rotational as well as alternative. These gears fit one another despite the difference in size due to the cogs. Gears help transform mechanical energy throughout the system of the apparatus. There are some key characteristics of gears which are: 

  • Gears are almost always used in pairs
  • Meshing gears have proportional sizes
  • The teeth or cogs of gears are of the same size
  • The teeth shape of meshing gears is the same
  • Teeth may be  parallel or to the oblique to the shaft axis

Pulleys

Pulleys are types of gears. But they have a different application. In pulleys, wheels are used. These wheels facilitate movements. It also transmits mechanical power. The transmission of power in pulleys happens from the wheel to the shaft or the cable, rope, or belts. Pulleys are simple machines as well. They are used in transportation and industries. Pulleys have the following elements:

  • Wheel
  • Rope
  • Shaft
  • Belts
  • Chains
  • Cable

Those pulleys which have grooved shapes are known as sheaves. The mechanical advantage increases when pulleys are used together. Pulleys can lift heavy weights due to this advantage. 

There are four types of pulleys. Those are: 

  • Movable pulleys
  • Combination of movable and fixed
  • Fixed pulleys
  • None of them

Pulleys can be used along with blocks and frames. Gears and pulleys are used together in other machines, wells, transport vehicles, and elevators. Construction pulleys are used in agricultural engineering. 

Belts

Belts are straps. These are tools that are used in a pulley system. Belts are used to facilitate the movement and direction of speed. Belts are a part of some bigger systems and machines. The belt functions as a medium. It runs through the groove of the wheel. Gears and pulleys are used together in other machines, wells, transport vehicles, and elevators.

Define Belts

Define belts are very common questions that come in GATE exams. To answer define belts, students must write those belts are straps. These are tools that are used in a pulley system. Belts are used to facilitate the movement and direction of speed. Belts are a part of some bigger systems and machines. The belt functions as a medium. It runs through the groove of the wheel. Through the belt, the energy is transmitted between pulleys or in the applications. Belts can either be in one direction or crossed. Belts are of many sizes.

Conclusion

Agricultural engineering is a science field. In this, engineering applications are used to enhance and improve agricultural output. Various applications of agricultural engineering can be seen in intersectional disciplines. The fields include electronics, software, civil engineering, food science, and environmental.