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Typical window applications are shown below:

Line focus

Powder diffractometer

Guinier camera

Point focus

Debye  -  Scherrer camera

Texture goniometer

Laue camera

Weissenberg camera

Precession camera

Reciprocal lattice explorer

3.6.

CHANGING THE X-RAY TUBE

To change the X-ray tube, proceed as follows:

1 . Switch off by pressing the GENERATOR 0 push-button.

2. Turn off the water supply.

3.

Drain water from the instrument by opening the air inlet valve next to the water inlet and outlet

connections, and wait until air has filled the system. Some water may run from the air inlet valve.

4.

Loosen the two captive screws at opposite corners on the top of the tube shield. The X-ray tube should be

removed by lifting upwards, when handling the X-ray tube take care to hold by the metal base and

!

DO NOT TOUCH THE BERYLLIUM WINDOWS. These windows are thin, and can be poisonous to the skin.
Do not remove the X-ray tube if generator operation has been switched off because of a failure
(safety circuit actuated) see Service section.

5.

Select the new tube and insert into the tube shield, after first checking the condition of the “0” rings

for the water tubes. There is a locating pin on the top of the tube shield to ensure correct positioning of

the tube. Tighten the two fixing screws.

NOTE:

The tube shield is designed to accept X-ray tubes with dimensions  as figure 3.3. version A.

For other tubes a spacer ring, such as PW 1043, will be necessary when the dimension from the
underside of the tube base to the centre of the tube base to the centre of the tube window exceeds 21 mm.

Note that dimension "a"  must not exceed 120 mm.

Fig. 3.3. X-ray tube dimensions.

Summary of Contents for PW 1720

Page 1: ...PHILIPS Table top X ray Generator PW 1720 Instruction manual ...

Page 2: ...sis by loading the sample film etc or positioning the goniometer or other device see also paragraph 3 4 l Momentarily operate the GENERATOR I push button and when the safety circuit is complete the X RAYS ON lamp s will light to show that X rays are being generated The lamp in the push button is also lit l Increase the kV control to the required value then adjust the mA control until the desired X...

Page 3: ...osure time of the film to X rays by using a PW 1722 timer Two timers can be fitted the left hand timer will control the shutter of either window 1 or window 2 and the other timer the shutter of window 3 or 4 This paragraph describes the automatic and manual control of the shutter operation When the camera is installed on its bracket in front of the required exit window of the tube shield open the ...

Page 4: ...operating the lowest SHUTTERS push button simultaneously with the required SHUTTERS I push button The shutter will open and the X ray beam passes to the sample in the camera the red lamp on the tube shield is lit and the red flags will appear in the holes on either side of the tube shield 4 When the exposure time has elapsed operate the SHUTTER 0 push button The shutter will close and the generato...

Page 5: ... The filament has a rectangular shape but the size depends on the type of X ray tube Focal sizes are Fine focus 0 4 x 8 mm Normal focus 1 x 10 mm Broad focus tube 2x 12 mm Two windows in the metal body are parallel with the long side of the focus the two other windows are at right angler to it The windows are at the same height with respect to the anode plane and they allow beam take off angler be...

Page 6: ... handling the X ray tube take care to hold by the metal base and DO NOT TOUCH THE BERYLLIUM WINDOWS These windows are thin and can be poisonous to the skin Do not remove the X ray tube if generator operation has been switched off because of a failure safety circuit actuated see Service section 5 Select the new tube and insert into the tube shield after first checking the condition of the 0 rings f...

Page 7: ... generator i e so that the X ray beams make angles of either 90 or 45 or 0 to the front of the generator However the rotation of the tube shield must not be more than 90 in either direction from its original position Since the line and point focus beams are 90 apart it is possible to place the tube shield with either beam in any position depending on the use of the generator or personal preference...

Page 8: ...3 7 ...

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