Bevel gears with spiral teeth


Bevel gears with Gleason-spiral teeth as Defawes ’96 is manufacturing them, are calculated on the basis of the transverse module and according to the same formula as the bevel gears with straight teeth for the reference cone angle. For the reference cone angle and the back angle, that are complementary, the values of our previous tables remain valid. However, all other characteristics undergo the influence of necessary corrections (addendum modification); full calculation should be entrusted to a specialist and thus all data of a transmission error must be submitted to us in order to design the correct dimensions and characteristics of the applicable gear pair.

The minimum data are in each case:

  • the transmission ratio to be used
  • the transverse module
  • the facewidth
  • the mounting distance of the pinion
  • the length of the calibree of the pinion
  • the mounting distance of the wheel
  • the power and rotational speed and or torque to the pinion
  • the rotational direction of the pinion according to the arrow

It is of course desirable to supplement this data with indications regarding the operating conditions (any overload; size and span; signs of shock; frequency of the switch; nature of the lubrication; number of operating hours per day; predictable lifetime). Bevel gears with spiral teeth must always be manufactured in pairs.

Note: with spiral bevel gears important axial forces occur; their direction and size change in function of the helix angle and direction of rotation. It is therefore necessary to provide a sufficient bearing (axial bearings).

Lubrication: even more than for a regular gear transmission the lubrication of the spiral bevel gears must be good; this needs to be more abundant than for bevel gears with straight teeth and a lubricating oil “extreme pressure” (with customized additives) is recommended.
It goes without saying that a mounting in a sturdy, not deformable casting with oil bath lubrication, stimulates the operational reliability.

Bevel gears at