Hofmann Megaplan Megaspin 800P_2, Руководство по эксплуатации и обслуживанию

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19
A B
Use and maintenance manual Rev. 02-2012
ENGLISH
6.5 RUN-OUT - ECCENTRICITY
MEASUREMENT (OPTION)
The much enlarged fi gures show the outer tyre surface and
axis of wheel rotation.
Figure
A
shows measurement of the total Peak-to-Peak
eccentricity de fi ned as maximum radial deviation of the tyre
surface.
Figure
B
shows measurement of the eccentricity of the 1st
harmonic, i.e. the eccentricity of the circle which “copies”
the tyre shape, by averaging the local tyre deviations from
the round shape.
Obviously the P.P. measurement is normally greater than
that of the 1st harmonic. Tyre manufacturers normally
supply two different tolerances for these two eccentricities.
At the end of the balancing run, it is automatically possible
to measure tyre eccentricity through the SONAR sensor
installed on the machine. The sensor should be positioned
by hand in front of the tyre tread. (max. wheel Ø: 1000
mm).
INDICATION
For 1st harmonic the max. deviation usually should not
exceed 1,2 mm. The symbol above button 4 changes to
red as soon as this value is too high.
GRAPH 1: indicates the effective Peak-Peak eccentricity
GRAPH 2: indicates the
fi rst harmonic eccentricity. For a
wheel in excellent condition, this graph should approach a
straight line.
When the wheel is moved, the cursor on the screen indica-
tes the actual value, with the phase referred to the correc-
tion point.
Enabled buttons:
prints the fi rst harmonic eccentricity value
(option)
return to measurement frame
perform a measurement spin
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