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Helical Gear in AutoCAD

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3 (60%) 2 votes

Helical Gear


Helical Gears Information:

Helical gears are cylinder-shaped gears. Its teeth are not parallel to the axis of rotation. The teeth are right-angled or left-angled and appear as a sector of a helix. Helical gears can transfer power between parallel or right angle axes.

Helical gears can transfer energy between similar or vertical axes through use of helical teeth. This is designed to allocate pressure regularly along the total tooth. Because of this tooth preference, helical gears run smoother and quicker than other gears and able to bring heavy loads capably. Outstanding to the incline of the teeth and the pressure applied, this gear is subject to axial drive. It can be treated by the use of thrust bearing and use specialized lubricant.


Helical gear is available in two teeth formations: these are left handed and right hand.

Helical gears transfer energy through two axial formations: these are parallel and perpendicular.


Dimension Specifications:

Gears helper via teeth with very definite geometry. Pressure angle of tooth drive action, or the angle between the line of force meshing teeth and the tangent to the pitch circle at the point of mesh. Usual pressure angles are 14.5° or 20°. Helix angle is the angle at which the gear teeth are aligned associated to the axis.


Gear configuration is resolute by submission, including the gear’s service, rotation speed, accuracy and more.

Cast iron provides strength and ease of production.

Alloy steel runs greater strength and erosion opposition.

Cast steel runs easier fabrication, strong working loads and vibration confrontation.

Carbon steels are low-cost and strong, but are subject to corrosion.

Aluminum is used when low gear inaction with some resiliency is required.

Brass is low-cost, easy to mold and corrosion resilient.

Say you draw a Helical Gear, you should know below trams:

  1. At 1st minimum two trams should know these are say number of teeth and module
  2. Say number of teeth(NT) : 18 Nos.
  3. Say module of Gear (M) : 10mm
  4. So Pitch circle Dia(PCD) : NT X M = 18 X 10 = 180mm.
  5. Addendum circle (ADD) : M= 10mm
  6. Duodenum circle (DED) : 1.125m  = 1.125 x 10 = 11.25mm
  7. Out site Dia (OD)                : PCD + 2 ADD = 180+2 x 10= 180+20=200mm
  8. Root Dia (RD) : PCD – 2 DED = 180-2 x 11.25= 180-22.50= 157.50 mm
  9. Whole Depth (HD) : ADD+DED=10+11.25=21.25mm
  10. Working Depth (WD) : 2ADD= 2 X 10= 20mm
  11. Circular Pitch (CP) : PCD X π /NT = 180 x 3.1416/18=31.41mm
  12. Tooth Thickness (TT) : CP/2=31.41/2=15.75mm
  13. Pressure Angle : 14.5® or 20®
  14. Helix Angle : 15®

gear in AutoCAD

helical gear in AutoCAD


helical gear in AutoCAD

helical gear in AutoCAD

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