Page 229 - Gear Technology Solutions

form errors which result in inconsistent contact pattern from one meshing pair of
teeth to the next. Furthermore, targeted flank form deviations have to be designed
in order to avoid edge contact along the boundaries of the teeth. Edge contact can
cause surface damage which could result in tooth fracture in case of high load ap-
plications. A further goal for a psychoacoustic motivated flank form scattering is to
provide gearset insensitivity to small variations in the shaft positions. In order for
closed loop correction and easy grinding machine input data handling, it is desira-
ble to have only one set of basic setting for one pinion or gear required instead of
one set of settings for each slot.

16.8 The Solution - MicroForm Surface Modifications

A two-level modification Technology called MicroForm has been developed,
where the first level changes the amplitude of the modification from tooth to tooth
and is defined as a Gauss normal distribution. The second level defines the math-
ematical function of the flank form modification as a sinusoidal curve. The sine
function is zero at the beginning of one period, zero at the center and zero at the
end of one period. This reduces or eliminates center and corner point deviations.

Figure 8: Phoenix axes instead of basic settings used for modulation

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