Abstract
The invention relates to a method of making a thread or tap on a cylindrical, conical or frustoconical piece to be machined.
The invention relates to a method of making a thread or tap on a cylindrical, conical or frustoconical piece to be machined.
According to the invention, this method comprises the steps of:
a) driving in rotation the piece to be machined in one direction),
b) carrying out a relative displacement of a first cutting edge of a tool relative to the piece to be machined until this first cutting edge is flush with the surface to be threaded of the workpiece at the beginning of the section to be threaded,
c) carrying out a relative displacement of the tool relative to the piece to be machined so that the first cutting edge machines the piece to be machined,
d) carrying out a relative displacement of the tool along the longitudinal axis of the piece to be machined, in one direction until the end of the section to be threaded,
e) moving away, by a relative displacement, the first cutting edge of the tool from the piece to be machined,
and it has the particularity of further comprising the steps of:
f) reversing the rotation of the piece to be machined to drive this piece in rotation in the direction opposite to the direction, while positioning or not the second cutting edge,
g) moving, by relative displacement, a second cutting edge towards the piece to be machined until this second cutting edge penetrates the thread pitch,
h) carrying out a relative displacement of the second cutting edge relative to the workpiece so that it continues the machining of the thread in the piece to be machined,
i) carrying out a relative displacement of the second cutting edge in a direction opposite to the direction, until the beginning of the section to be threaded,
j) moving, by a relative displacement, the second cutting edge away from the workpiece to be machined,
k) reversing the rotation of the piece to be machined, while positioning or not the first cutting edge then
l) repeating steps b) to k), while continuing the machining of the thread, until the thread reaches its final dimensions, while positioning the first cutting edge in step b) in such a way that it penetrates the thread pitch already machined.
patents