Gears are toothed mechanical transmission devices that are used for motion and power transfer between different components of a machine. They work in mated pairs by meshing their teeth with those of a corresponding toothed device to help prevent slippage. One of the common categories of gears that you will get out there is the spur gear design. It is used in a wide range of industries, from industrial machinery to agricultural equipment, but how exactly does it work? Keep reading to learn more about spur gears, their design, and applications. 

What is a Spur Gear?

Spur gears also referred to as straight-cut gears, are some of the simplest types of gears that you can get out there. They are designed with a cylinder featuring teeth that project radially. Therefore, viewing the gear at a 90-degree angle from the shaft reveals the teeth as straight and aligned parallel to the axis of rotation. See the image below. 

Depending on your application, spur gears can be mated with other spur gears or a gear rack like the pinion gear pair. Because of their simplicity, spur gears' design allows for an excellent level of precision and manufacturing. Other attributes of spur gears include: 

• High-speed capability. 
• High loading capacity. 
• High-efficiency rates. 

Even with these impressive attributes of spur gears, they are not without a few cons. The most notable is that they produce a lot of noise, especially during high-speed applications. Also, their teeth experience a lot of stress, especially when carrying high load capacities. 

The Two Main Types of Spur Gears 

Spur gears can be broadly categorized into two, the external and internal models. The external spur gears are designed with teeth that are machined on the outer surface. If you mesh two outer spur gears, they will move in the opposite direction. 

Unlike the external spur gears, the internal spur gears have their teeth cut on the inner surface of their cylindrical body. If you mate an external gear with internal gear, they move in the same direction. This is one of the concepts applied in the design of gearboxes. Since the shafts are positioned closer to each other, internal spur gears are mainly used for planetary gear drives.  

Where are Spur Gears Used?

Spur Gears are mainly used to help transfer motion and torque between two shafts, the driving and driven, in a mechanical setup. Therefore, they make an excellent choice for users targeting to alter machinery’s speed, multiplying torque, and supporting fine-tuned control of positioning systems. Here are some of the common applications for spur gears. 

• Power plant machinery. 
• Watering systems. 
• Pumps. 
• Conveyor belt systems. 
• Drying machinery. 
• Machining tools.
• Material handling equipment

Spur gears are considered the best option for applications that require torque application and speed. Even though they have a wide range of applications, make sure to only go for the model that matches well with your equipment. Furthermore, you need to ensure the spur gears are installed correctly and maintained in top condition for high productivity and a longer lifespan.