American Dryer Corp. ML-410 - Manual (Page 37)

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1. Filter/Regulator Assembly
The compressed air supply to the dryer is connected into the 3/8” F.T.P. fitting of the filter/regulator assembly
which is located at the bottom rear of the right side of the base.
The filter/regulator assembly performs two (2) essential functions. The filter removes most solids and
liquid particles from the compressed air stream and traps them in its bowl where this waste can be readily
removed through the drain valve at the bottom of the bowl.
The filter bowl should be cleaned monthly.
The regulator will remain a nearly constant outlet air pressure so that the dryer’s pneumatics will function
normally despite upstream air pressure variations. After the compressed air is connected into the filter/
regulator assembly, adjust the regulator knob so that the gauge needle reads 80 PSI (5.512 bars).
2. Tilting-Piston Solenoid Valves
A two-way-tilt dryer has two (2) of these solenoid valves...one to control the front set of tilting pistons and
a second to control the rear set of tilting pistons. A one-way-tilt dryer has only one (1) pair of solenoid
valves.
Each valve has five (5) 3/8” F.T.P. ports and two (2) electric solenoid operators, one (1) on each side of the
valve.
To tilt the dryer forward, a 24 volt signal is applied to the rear pistons solenoid connector “12” and no
voltage is applied to the solenoid connector “14”. The internal spool in the valve will move and 80 PSI
(5.512 bars) of air will enter the bottom port of the rear tilting pistons, extending the rear tilting piston rods
and tilting the dryer forward for unloading. The top piston ports are bled to the atmosphere.
To level the dryer, the voltage signals are reversed. No voltage is applied to the “12” solenoid, and 24 volts
is applied to the “14” solenoid. The valve spool will now move so that 80 PSI (5.512 bars) of air is applied
at the top piston ports, while the bottom piston ports are bled to the atmosphere. The piston rod will now
retract leveling the dryer. On rear tilt dryers, the front tilting piston solenoid valve acts in the same manner.
The tilting piston valves are 4-way/5 port/3 position valves. If no voltage is applied to both the “12” and
“14” solenoids, ALL five (5) valve ports are blocked. This means that, if the dryer is tilting or leveling and
power to the dryer is shut off, the pistons will lock in position, holding the dryer in a partially tilted
position.
The tilting piston valves and flow control valves are located on the pneumatic plate in the rear of the dryers’
base.