BULETINUL INSTITUTULUI POLITEHNIC DIN IAŞI - Universitatea ...

Bul. Inst. Polit. Iaşi, t. LVI (LX), f. 2, 2010 35
only of the values from the peak of the tooth (Fig. 3). The minimal values (that
must have a specified value) are determined on the base of mathematical
relations,
but the real angles' variations not controlled.
If the intersection of the tooth with planes parallel with a medial plane of
the tooth is realized (posterior planes, Fig. 4), we obtain different values for the
angles αp and γp (the plane Pp
- Pp) in the points of
intersection between these
planes and the cutting edge
from the involute flank. The
points in which the
determination is made can be
however dense (from example
0.01 mm), but such frequency
is not necessary, because the
variation limits and the
variation mode can be
observed in only some points,
and that fact simplify
determination operations.
the
Fig. 4 – The intersection of the
tooth
with paralel planes.
The Solid Works computer
program, by the facilities
that are offered, give directly
under the form of a quote the
values obtained for the angles
determined in these planes.
Using a program that permits
the drawing of the mentioned
planes at determined
distances, with a pre
established step, becomes
Fig. 5 – Intersectio ns with orthogonal planes.
possible to obtain the desired
values in every point on the
edge, and with these values it
is possible
to draw a chart
(Fig. 6).
Similarly, it is possible to
construct normal planes at the
cutting edge's tangent in the
anterior determined points on
that edge, or orthogonal planes (Fig. 5). Obviously, in these planes are
determined the angles αn and γn, or the angles αO and γO.
The determination
conditions
are similar with the before precise conditions.