TXR 325D, Руководство по обслуживанию

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M-2008-7-15
Standard Frequency Series Generators
Maintenance 21
SECTION 8
COLLIMATOR
8.0 THEORY OF OPERATION (Eureka Collimators)
All collimators used in general radiography work on the same principles. We use Progency products
in many of our applications so we will devote this section to the way they work. A full section in the
Installation Manual is devoted to every aspect of installation, alignments, testing and validating its
operation.
8.1 MECHANICAL OPERATION SOURCE TO IMAGE DISTANCE SELECTION
The EUREKA LINEAR™ MC150 Collimator contains two major sets of shutters, long and cross,
which define the absolute X-ray field size. There is also a fixed aperture cone which protrudes into
the port of the X-ray tube that helps reduce the effects of off-focus radiation.
Both shutter mechanisms are geared with anti-backlash mechanisms coupled though shafts to
SID indicator scales and knobs on the front panel. The shutters are positioned manually with these
knobs. Back-illuminated SID scales indicate all conventional film sizes for both 100 cm and 180 cm
SID’s, as well as 40 inches and 72 inches in SIDs.
All Eureka Linear Series collimators have a swivel mount configuration. Detents are located at 90
degree increments. The collimator may be oriented to any position for achieving proper X-ray field to
cassette alignment for table-top or non-bucky operation.
The shutter mechanism has been precisely aligned with respect to the mounting flange at the
factory. Therefore, the necessity for field alignment of the central ray has been virtually eliminated.
8.2 ELECTRONIC OPERATION
Refer to Schematic 70-08372 and Assembly Drawing 70-08371.
This drawing is provided with the Eureka Manual.
8.2.1 POWER SUPPLY
The Linear MC150 is designed to accept power from either a fused customer supplied 24 VAC
source or by means of an optional power supply P/N 70-20254.
In the case of a 24 VAC supply, power is supplied to the linear display PCB 70-08371 where it is
rectified, filtered and regulated by bridge B1, capacitor C1, and regulator VR1 respectively.