Large Gears: Types/Sizes

SPUR

Most common gear type, Recognized by Straight Cut tooth form, Teeth run parallel to the axis of rotation resulting in less loading of the support units.

Varied tooth pitch, gear forms and pressure angles can be used to achieve desired gear ratios and running characteristics. Lower pressure angle result in smoother, quieter running. Higher pressure angles generally offer better load carrying capacity.

HELICAL

Helical gears have teeth that run at varied angles to the axis of rotation resulting in some side thrusting of the loads.

The helix angle, tooth forms and pressure angles are varied to achieve the desired ratios and running characteristics but helical gears generally run smoother and quieter than Spur gearing.

The increased angle of the tooth can allows an increase in the effective face of the gear by as much as 75% resulting in a comparable increase in load rating.

DOUBLE HELICAL/HERRINGBONE

Double Helical gears are essentially a combination of a right and left hand helical gear.

Double Helical gears offer the same operational advantages as helical gears; quieter, smoother running and increased load capacities. In addition, the combination of both the left and right hand helix eliminates the axial thrust loading found in single helical gears.

BEVEL GEARS

Bevels are the most common gears for intersecting shafts. Used as a method of transferring power on angle drives.