Harig AUTOMATIC PLC, Manual

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e turned way down), an
may be seen. If the grinder has not been operated for a long
dditional 1/3 turn. Running the table back
Release plunger before reaching end of travel. If the table will not move by dressing the plunger
(Note: Plunger is difficult to push), the valve should be replaced. If the table travels by manually
activating the solenoid, proceed to the electrical checks.
B. Jumpy table movement.
the grinder is being operated at a very slow speed (speed control valv If
irregular movement or “jump”
period of time, this may be due to air in the cylinder. The air can be removed from the cylinder
by setting the table travel for an 8 inch stroke and operating the table at full speed for a short
period of time.
Insufficient lubrication of the longitudinal ways can also cause this problem. More oil can be
d to the ways by opening the restricting valve an a fe
and forth a few times before taking a cut will help distribute the oil evenly over the ways to
minimize this condition.
8. CROSS FEED MALFUNCTION
A. Normal Operation.
utomatic cross feed occurs when the electric A module turns on the stepping motor. The feed
e hydraulic control output relay changes states as the table changes cycle is started when th
direction. Cross feed continues until the electronic module has moved the stepping motor the
correct number of steps; each step equal .0001”. The feed distance can be set from .0001” to
1.0000” in .0001” increments.
NOTE:
If the table reverses before completing a cross feed, the electronic module will reset and
give a complete feed from that point. The force to turn the cross feed screw is transmitted from
the motor through the coupling to drive sleeve which has a square hole broached in its end. The
slip fit between this hole and the square shaft that is pinned to the end of the cross feed screw
allows the screw to travel back and forth with the saddle and still be driven by the stationary
motor. The direction of feed is control by the direction of rotation of the motor. Motor rotation is
changed by proximity switch and trip dog bracket.
B. Hand feed wheel turns hard.
e sure cross lock thumbscrew has been loosened B