Author: Haroon Khalil

Bevel Gears Bevel gears are primarily used to transfer power between intersecting shafts. The teeth of these gears are formed on a conical surface. Standard bevel gears have teeth which are cut straight and are all parallel to the line pointing the apex of the cone on which the teeth are based as shown in Figure…

Double helical gears have one a right-hand helix and the other a left-hand helix. The teeth of two rows are separated by a groove used for tool run out. Axial thrust which occurs in case of single helical gears, two rows of teeth cancel each other. This can be run at high speeds with less…

Helical gear is similar to the spur gear except that the teeth are at an angle to the shaft, rather than parallel to its axis as in a spur gear. The resulting teeth are longer than the teeth on a spur gear of equivalent pitch diameter. The longer teeth cause helical gears to have the…

General: Spur gears are the most commonly used gear. They are characterized by teeth which are parallel to the axis. The basic descriptive geometry for a spur gear is shown in Figure 15.18. Advantages: Spur gears are easy to find, inexpensive, and efficient. Limitations: Spur gears generally cannot be used when a direction change between the two shafts is…

Gears can be classified according to position of shafts as follows.

There are mainly two forms of gear teeth: Forms of Teeth There are mainly two forms of gear teeth: Cycloidal Profile Teeth A cycloid is the locus of points on the circumference of a circle that rolls without slipping on a fixed straight line. An epicycloid is the locus of points on the circumference of…

The law of gearing gives the condition for the tooth profiles for constant angular velocity for two mating gears, which can be explained as: “If angular velocities of two mating gears remain constant, the common normal at the point of the two teeth should always pass through a fixed point P which divides the line…

All the important gear terminologies are shown in Figure 15.14. Pitch Point: The point of contact between pitch circles of two gears is known as pitch point. Pitch Circle: The circle passing through point of contacts of two gears is known as pitch circle. Pitch Diameter, D: Diameter of pitch circle is known as pitch diameter. Circular Pitch, Pc: It…

Gears are compact power transmission device that controls the speed, torque, and direction of rotation of driven shaft. Gears may be classified into five main categories: spur, helical, bevel, hypoid, and worm. Shaft orientation, efficiency, and speed determine the application of gear drive. Gears are toothed disc which transmit power from one shaft to other…