Parallel Helical Gear Vs Crossed Helical Gear

Parallel Helical Gear Vs Crossed Helical Gear


Parallel axis helical gear Material:Steel 20NCD2 Module:1.25 ...Crossed Helical Gear - View Specifications & Details of Helical ...
Parallel Helical GearCrossed Helical Gear
Parallel helical gears can transmit motion and power between parallel shafts only.Crossed helical gears can transmit motion and power between perpendicular but not-intersecting shafts.
Two mating gears must be mounted on two parallel shafts.Two mating gears are mounted on two perpendicular but non-intersecting shafts.
Two mating gears should have same helix angle but opposite hand of helix.Two mating gears may have different helix angles. They may have either same or opposite hand of helix.
Engagement between two teeth starts with a point contact but gradually becomes a line contact.Two meshing teeth always have point contact.
Power transmission capacity of parallel helical gear is higher due to broader contact.Crossed helical gear has lower power transmission capacity due to point contact.
It has wide area of application ranging from small equipment to large industrial field including gear trains.It is rarely used in small size instruments.

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