HS50_advance_level 1_20200522_221201 (1).pdf - 第554页
Studen t Guide HS-50 A dvanced I 06/200 2 Edition 20 App endix 27 tion , click on the In iti ali z e s te pp e r mo t or button i n the "T urning station" f ield. – T o m easure the current vacuum v alues in th…
06/2002 Edition Student Guide HS-50 Advanced I
20 Appendix
26
20.4.4.4 Functions of the RV Head in the Holding/Reject Circuits
– If you wish to test the head functions in the holding and reject circuits, click on the icon
in the
"RV head" display to switch to the "Head board RV head, holding and reject circuit".
20
Fig. 20.4 - 2 "Head board RV head, holding/reject circuit" Display
Key:
a to switch the vacuum on/off
s to switch the air-kiss function at the reject station on/off
d to swivel the dp-drive in/out
– If you wish to test, for example, the head functions during the swivel-in motion of the dp-
drive, activate the corresponding radio button in the "Turning station" field.
– To move the stepper motor for the swivel-in mechanism of the dp-station into neutral posi-
12 3
Student Guide HS-50 Advanced I 06/2002 Edition
20 Appendix
27
tion, click on the Initialize stepper motor button in the "Turning station" field.
– To measure the current vacuum values in the holding circuit, click on the Vacuum in hold-
ing circuit button. The measured value is displayed above the button.
NOTE
Prior to the execution of the "Close nozzles" function, a head reference run must have been
performed on the RV head. 20
– If you wish to measure the vacuum with the nozzles closed, click on the Close nozzles but-
ton prior to the start of the vacuum measurement.
20.4.4.5 Functions of the Z axis top and bottom light sensors
The light sensors at the top and bottom positions of the Z axis perform several functions which are
detailed below.
1. Functions of the top-light sensor of the z-axis on the revolver-head?
– To activate the bottom light sensor z-axis when z-axis moves downward.
– To start x/y-axes when z-axis moves upward.
– To reset both light sensors of the z-axis when z-axis moves upward.
– To switch the solenoid which supplies the air pressure.
– To activate the vacuum for nozzles (pick-up process) which are programmed in the file
vak_z.ma.
To activate the vacuum test after pick-up.
– To activate the feeder transport apart from 8mm Schulz. However 8mm Schulz if reduced ac-
celeration is used for z-axis
– To activate the vacuum test after placement to check whether nozzle is leaking.
With the latest software this test is not done with the top light sensor anymore. It is done before
the z-axis moves downward for pick-up.
2. Functions of the bottom-light sensor of the z-axis on the revolver-head?
– To switch vacuum on (pick-up)
– To switch vacuum off and air kiss on (placement)
– To provide the end signal for the z-axis for placement force 1-2 Newton.
06/2002 Edition Student Guide HS-50 Advanced I
20 Appendix
28
20.4.5 Threshold Values of Vacuum Check
20.4.5.1 Vacuum measurement and calculation at reference run
Fig. 20.4 - 3 Vacuum measurement and calculation at reference run
1. Two vacuum measurements are made at reference. 1st with value closed and 2nd with the
value open and air passing through the nozzle.
2. The closed value is dependant on the environment pressure which can vary greatly, depending
on local weather conditions and altitude. Basically the higher the altitude the lower the environ-
mental pressure therefore the lower the closed vacuum.
3. The open value is dependant on nozzle size and nozzle type condition. The smaller the nozzle
the larger the open value. In the same way a contaminated or blocked nozzle will also give a
large open value.
4. The difference between open and closed nozzles as a minimum value is pre determined by the
line computer generated ideal.MA. This is different for all nozzle types. E.g. 120 mbar for 714,
704, 914 and 904 nozzle. If these values cannot be reached, the error message "Intervals
open/closed insufficent" will appear.
-700
-720
-740
-760
-780
-800
-820
-840
-860
-880
-900
0
t
maximum vacuum
Vacuum nozzle closed
Vacuum nozzle open
The difference in the results of the
2 vacuum measurements should larger
than the minimum value from LC.
Environment pressure
20% for reject
80 % for acceptance
at vacuum check
Threshold = (vac. closed -vac. open)x0.2 + vac. open
Pressure difference nozzle - inside -> environment