In this masters thesis we have designed a new shape of interlocking staples for the
manufacture of rotor packages. We have investigated the effect of the new shape of
staples on tool design and package delamination force.
First we measured the force needed for production of staples for all of the desired shapes
on three different metal sheets. Three of the tested staples shapes, were then chosen
for production of rotor cores in a progressive interlocking blanking tool. Delamination
forces of produced rotor cores were measured on a tensile strength measuring machine.
We came to a conclusion, that slightly more force is needed for stamping of staples with
punch with surplus measure than for the normal sized staples, but adding chamfer on
the punch helps lower the stamping force for the surplus measured staples.
Delamination force measurements of the produced rotor cores have showed us, that
cores stacked with the new shape staples tend to delaminate a little easier than the ones
made with usual shaped staples. On the other hand we can conclude that delamination
forces of rotor cores made with new staples are more predictable due to lower standard
deviation of the measurement.
We came to understand that the new shape of clips does not have any notable downsides
to the construction of progressive blanking tool or to rotor stack delamination force. We
also realized that the new shape of clips has positive influence on production stability
and tool testing period.
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