Planmeca Proline EC ceph, Technical Manual

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Chapter I - FUNCTIONAL DESCRIPTION
Planmeca Proline EC X-ray unit I-5
MECHANICAL CONSTRUCTION AND OPERATION
Technical Manual
1.3 Cassette mechanism, Planmeca Proline EC Pan/Ceph X-
ray unit
The primary function of the cassette mechanism is to enable controlled linear movement of
the film cassette across the radiation beam synchronically in relation to the rotation move-
ment. Besides, the cassette mechanism has certain secondary functions such as secondary
slot which prevents the radiation scattering from patient from exposing the film and Frankfort
positioning light reflector which produces a horizontal light beam to facilitate patient position-
ing.
The assembly (Fig. 4, 1) is the frame of the cassette mechanism. A carriage (Fig. 4, 2) is
attached with bearings and axles (Fig. 4, 3 and 4) to the frame. The panoramic carriage is
locked to the frame.
The cassette holder (Fig. 4, 5) is attached with linear bearings to the carriage through axle
(Fig. 4, 6) and support wheel (Fig. 4, 7). The cassette carriage is driven by an friction wheel
(Fig. 4, 8) which is in contact with the top surface of the carriage.
The lateral force caused by the cassette holder, the weight of the film cassette and the load-
ing spring of the driving wheel is compensated by a support wheel in the carriage (Fig. 4, 2).
The cassette holder rolls against the support wheel. The secondary slot (Fig. 4, 9) is attached
to the carriage (Fig. 4, 2). Commanded by the microprocessor a stepper motor (Fig. 4, 10)
rotates the friction wheel analogically with the rotation mechanism through worm gear trans-
mission.
The cassette mechanism is shown below.
Figure 4
1
4
8
3
2
6
9
10
5
7