PA Industries Precision AirFeed - Manual (Page 10)

8
CONTROLLING THE FEED
MECHANICAL ACTUATION
Install a Support Bar with a Plunger on the upper Die
Block of the Tool or on the Press Ram. The vertical
Plunger should be threaded to allow vertical height
adjustments. The Plunger should contact the center
of the Feeder’s Actuating Valve Stem. After contact,
and during the first 1/4" (6mm) of downward Valve Stem
travel, nothing happens with the Feed Slide Control.
During the next 3/16" (5mm) of travel, the Mechanical
Actuation Valve opens causing the clamps to shift and
the non-feed stroke begins. The remaining down-
ward stroke of the Valve Stem is over-travel.
When the Press Ram passes BDC and begins to
move upward, the Valve Stem reverses travel direction.
As the Plunger moves off the Valve Stem, the
Mechanical Actuation Valve closes causing the clamps
to shift and the Feed Slide to begin the feed stroke.
Installing a Spring on the Plunger to contact the
Actuating Valve Stem will result in a more desirable
Feed Cycle for Presses with long strokes.
AIR FEED
MECHANICAL
ACTUATING
VALVE
VALVE
STEM
PLUNGER
RAM
RAM
RAM
TDC TDC
SPRING
COMPRESSED
SUPPORT
BAR
PRESS CRANKSHAFT
ROTATION
CAUTION! Excess over-travel will damage the Feed