Spur gears are one of the most common types of gears used in industry and machinery. They are generally used to transmit rotational motion and power between two shafts that are parallel to each other. They can be found in a wide range of applications, from small toys to large industrial machines. These gears mainly have two types: internal and external. Internal gears have teeth on the inside surface of a cylinder or cone, while external gears have teeth on the outside surface of a cylinder or cone.

 

Fundamentals of spur gears

These gears are classified according to the geometry of their teeth. The most commonly used spur tooth profiles are involute, cycloidal, and trochoidal. Involute spur tooth profile provides good contact between the teeth of meshing gears and results in low noise and vibration levels. 
Cycloidal spur tooth profile provides smoother operation than involute gears and is often used in high-speed applications. The trochoidal spur tooth profile provides a very smooth operation. 


Spur Gear Design
There are a few things to consider when designing gears, including tooth shape, pressure angle, material, and more. This guide will cover all the basics of gear design that we at True Gear & Spline Ltd. give importance to so as to ensure top-notch quality gear for all our clients.
 

Tooth Shape
The first thing to consider when designing these gears is the tooth shape. The two most common tooth shapes for the spur type of gears are involute and circular. Involute teeth have a curved profile, while circular teeth are more like a series of flat faces. Each tooth shape has its own benefits and drawbacks, so it's important to choose the right one for your application.
 

Pressure Angle
The pressure angle is the angle between the face of a tooth and the plane perpendicular to the pitch line. The most common pressure angles for the spur type of gears are 14.5° and 20°. Lower pressure angles (14.5°) create weaker teeth that are more prone to wear, but they also allow for higher-speed operation. Higher pressure angles (20°) create stronger teeth that can withstand more force, but they also create more friction and heat during operation.
 

These gears are relatively simple to design and manufacture, and they can be used in a wide variety of applications. In this guide, we have covered everything you need to know about spur gears, from how they work to how to select the right gear for your application. Contact us today to source the best gears, including spur, helical, and bevel gears.