Planmeca Proline CC, Technical Manual

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Chapter I - FUNCTIONAL DESCRIPTION
I-10 Planmeca Proline CC panoramic x-ray
Technical Manual
Layer/hold limits (105-10-07)
This circuit board is located at the layer adjust mechanism in the lower fixed part. It’s function is
to detect the layer adjust motor and the temple rest motor limits and pass the information to the
keyboard processor via a 6-pole cable.
When replaced the layer adjust and temple rest motor operations should be checked.
Primary position detector (105-10-08)
This circuit board is located at the inner side of the tube head, above the collimator. It detects the
reference point of the primary aperture mechanism and passes the information to the generator
processor via a 3-pole cable.
When this circuit board is replaced or even moved from it’s place the primary apertures must be
aligned. It is impossible to “put it back to the very same place”, because it should be repositioned
with an accuracy of 1/100 mm.
Display/keyboard (105-10-09)
This circuit board is located in the keyboard housing below the lower fixed part. It’s function is
rather obvious, to drive the displays according to the information it receives from the keyboard
processor and to pass the information of the keyboard states to the keyboard processor via a 6-
pole cable.
This circuit board can be replaced without any further actions.
F1 protects the circuits on this board and is rated 1AT
2.3 Motors
There are six motors in the equipment that perform all the movements needed. In the following is
explained where the motors are, what they do, where they get their driving power from and what
is the system how they are operated.
Five of the motors are stepper motors the operating method of which is different from the DC-
motor. They have two coils with two wires to each and the current is flowing through the coils in
both directions in turn with a phase difference that causes the rotation. Now, if the stepper motor
is wrongly connected or one or two wires are broken the motor might run not at all, run with low
torque, run to wrong direction, change the rotation direction by itself or run at double or half
speeds. To check this the coil resistances should be about 5 ohms each and one coil connected
to connector pins 1 and 2 and the other to pins 3 and 4. If it runs to wrong direction just reverse
one coil polarity. Reversing both causes nothing. Measuring the voltages needs an oscilloscope
because the motors are driven by about 40 kHz switch mode current regulated power supplies.
Best to have a reference motor with or to cross connect two motors to check the driver circuit
operations. If cross connecting, remember that the limit sensors operate wrongly.
Up/down motor
The up/down motor is located on the top of the column. It’s function can clearly be seen, it is
moving the actual X-ray part in vertical direction along the column. It is a DC brush motor with a
worm gear of 1:72 and it gets it’s drive from the keyboard processor first downwards along the
spiral cable (on the left side seen from the front) and then upwards along a cable located inside
the column.
When this motor is activated, it is first driven one second slowly and then accelerated softly to full
speed. When the button is released the motor stops immediately if it was still in the slow mode,
but slows down softly if it was running faster. If the motor is driven to the end of it’s traverse path
(limit sensor) the system performs a quick stop by using the motor as a brake (short circuit). The
motor speed is controlled with pulse width control at 200 Hz frequency, that can be heard as a
humming sound.
The slow speed can be adjusted independently to both directions to fulfil all needs.