automotive engine distribution system (which are generally made of rubber with nylon strands).
Considering that the service time for the automotive toothed belts is around 100.000 km
(60.000 miles), assuming a medium regime of 2.000 rpm and thermal stress from 0 to 90°C (30
to 195 F) in a few minutes, we can think that the life cycle of the M-zero obs toothed belts will
be extremely long! It is important to underline that in the gear-worm systems the motion
transmission has only one tangent point of contact, any errors on each of the two components
will, sooner or later, result into a tracking errors. On the contrary, in the pulley-toothed belt
system, no direct contact occurs between the pulley and the motion is transmitted by the belt
engaging from 50% to 90% of the girth surface. Consequently any error, eventually present, is
averaged among the cogs, moreover soft, greatly reducing the tracking error.
No wearing effects since no relevant frictions occur. In fact, all the pulleys and the axes rotate
on roller bearings, 13 for the RA axis and 13 for the DEC axis that allow to reduce the total
friction almost to zero.
Another significant advantage of very low frictions is that the risks of motor slipping during
GOTO operation is virtually null. On the contrary, it is well known the difficulty to regulate the
coupling between gear and worm in the conventional mounts. If the coupling is tight the motors
can stuck with consequent loss of the position, if the coupling is too loose the plays increase.
On the other hands, the absence of significant play in the M-zero makes the initial calibration of
guiding CCD quick and easy.
Since there are no gears, there is no need of periodical lubrication of the internal components
and therefore the maintenance is extremely reduced and limited to the external cleaning.
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