EVACreservestherighttomakealterationstothisspecificationwithout priornotice.
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EVAC
CommercialMarineEquipment
VV
VV
VAA
AA
ACUUMCUUM
CUUMCUUM
CUUM TT
TT
TOILETOILET
OILETOILET
OILET
OPERATIONANDMAINTENANCE
Date: Doc.
23 Aug 2005 3:01025C
5775500 CONTROLMECHANISM, EVAC 90,SQUATTING TOILET
Description of flushing sequence
In the standby position FIG.1
Controlvalve1isclosed.Vacuuminchambers2and3isequalized
by the jets 4 and 5. Spring force 6 holds the mechanism in the
non-activatedposition.
In the just switched position FIG.2
Airpressureapplied fromthe flushbuttonto chamber7has lifted
thelever8andopenedcontrolvalve1.Atmosphericairhasentered
chamber3throughfilter9andvalve1.Theforcefromthepressure
differencebetween2and 3hasmovedthe shaft10tothe leftand
thefollowing sequenceof eventshas occured:
The inlet valve 11 has closed. Vacuum valve 12 has opened.
Vacuum is distributed via check valve 13 to discharge valve 18
and water valve 19 which will both open. Chamber 14 is also
subjectedto vacuumthrough check valve21.
This vacuum will pull lever 8 and close valve 1 and the timer
functionwill start.Chamber3 willbeevacuated throughjet 5and
the pressure difference 2-3 equalizes. At a certain level, the
counterforce from spring 6 will outweigh and the cycle will go in
theopposite direction:
Thevacuumvalve12willclose.Theairinletvalve11willopenand
atmosphericairentersdischargevalve, watervalveandchamber
14.Thedischargevalve18willcloseandsomewhatlater(because
of the jet 17), the water valve 19 closes when a suitable water
levelhas been reachedat the bottomof thebowl.
Returning to standby position FIG. 3
The whole system goes to standby position ready for another
VT-flush.
! NOTE: Diaphragm 16 has the same effective area as the air
inletvalve 11 tobalance thevacuum forces.FIG.3
!NOTE: Checkvalve13ensuresthatconnectedvalvesinactivated
positionare unaffectedby changesin thevacuum supply level.
! NOTE: If vacuum is too low or absent the
functionis delayed.Control valve1 staysopen untilchamber 14
is subject to vacuum.
