Page 332 - Gear Technology Solutions

23 Blade Stepping and Top Slope

23.1 The Purpose of a Top Slope Angle

If the top tangent of a cutting blade matches the X-axis of the blade coordinate
system, then the top slope angle is zero. In case the blade top tangent is
sloped up from the cutting edge towards the clearance edge as shown in
Figure 1, a negative top slope angle exists. The top slope angle is defined as
negative, if it exposes the clearance side blade tip. This means, in order to
have matching top slopes on an outside and an inside blade, the amount of
both top slope angles has to be identical, with the sign reversed. The top slope
angle for the mating inside blade (of the outside blade in Figure 1) therefore is
positive.

Figure 1: Face cutter head with outside blade featuring
a negative top slope angle

Top slope angles are applied in order to match the ideal root bottom
orientation of the work piece slots even in cases where the cutter head is tilted
around the flank line tangent of the work piece. In Figure 1, a typical slot profile
with a slot bottom matching the top slope direction was superimposed on the
cutting blade (purple profile). This kind of tilt angle is used in connection with

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