Planmeca Proline CC, Техническое руководство

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Chapter D - ADJUSTMENT & CALIBRATION
Planmeca Proline CC panoramic x-ray D-23
Technical Manual
5.3 Rotation limits
NOTE The adjustment of the patient position mechanism must be performed before adjusting
the rotation limits.
The rotating movement is controlled by two Hall detectors: one determines the start position and
the other the end position. The latter has no importance for the normal function because the step
motor drives the rotating unit according to the programmed number of steps The end limit is of
great importance in case of abnormal function, because it informs the processor that the rotating
unit has not reached the end position.
The start limit is adjusted so that the movement of the guidance wheel in the drawing groove is
symmetric to the groove. The distance of the boss of the wheel from the end of the groove should
be the same both when the movement starts and when it ends. The symmetricity of the move-
ment has more importance to the quality of the radiograph than the absolute length of the move-
ment which varies a little because of production tolerances.
Remove the necessary covers. Slide the ball phantom into the patient positioning mechanism.
Check that the y-line on the ball phantom is parallel to the line on the underside of the alignment
ruler according to instructions given in section “Patient positioning mechanism adjustment” on
page D-14.
Remove the alignment pin. Enter the test mode if you are not already in it.
Press the ready key to drive the x-ray unit to the exposure position. When the x-ray is ready the
indicator light will come on. Place the alignment ruler in position between the primary and sec-
ondary slot and write down the angle between the ball phantom “start”-line and the alignment
ruler.
Start to take a test exposure by pressing and holding down exposure button on the remote con-
trol until the rotation unit has reached the end position. Place the alignment ruler in position
between the primary and secondary slot and write down the angle between the ball phantom
“end”-line and the alignment ruler.
The positions corresponding to end and start positions should not differ more than ± 1 mm. The
position of the start limit (Hall detector) can be changed by unscrewing the screws. This should
be repeated until the tolerance area is reached.
The adjustment of the end position is done after the start position has been adjusted.
No special tools are needed. The end limit should activate about 5 mm before the end of the
movement and it should activate even when the rotating unit is at 5 mm past the end position.
The indicator light shows this when the equipment is in the service mode.
READY
PRET