TM 5-3610-253-14
When the backgauge control knob is pulled out, switch (S10) is closed. This sends
+24 V to the positioning computer interface (IAR) circuits. The IAR circuits
recognize this as a forward command. This forward command is sent to the positioning
computer (AR) and then back through the IAR circuit, then to the motor logic (ML)
circuits. The ML circuits then energize electronic relays V1M, V2M, and V3M in the
motor control (MC) circuit. Power is then applied to the motor and forward motion is
started. When the push button on the backgauge control knob is pressed, switch (S14)
is closed. This sends +24 V to the IAR circuits. The IAR circuits recognize this
as a backward command. This backward command is sent to positioning computer (AR)
and then back through the IAR circuit, then to the ML circuits. The ML circuits
again energize electronic relays V1M, V2M, and V3M, along with relay K15M. This
relay reverses the wires on the motor which allows the motor to rotate in the
reverse direction. The backgauge now starts to move back.
Limit switches mounted along the table bed where the backgauge runs limit the
distance the backgauge can travel in either direction. The switches are activated by
a pair of nylon trip dogs that ride on the backgauge sledge. Limit switch (S13)
limits the backward travel of the backgauge. When the backgauge is traveling
backward and reaches the most backward position allowed, it causes the trip dog
to trip, (open), and switch (S13) will cut off power to the motor. When the
backgauge is moving forward, two limit switches are used. Switch (S9) is used when
the false clamp is not installed. This allows the backgauge maximum forward travel
toward the cutting line. Switch (S8) is used whenever a false clamp is installed.
Switch (S6) indicates that a false clamp is installed. When a false clamp is
installed, switch (S6) is actuated, allowing limit switch (S8) to cut power to the
motor when activated. Limit switch (S8) will stop the backgauge at a shorter
distance than normal to provide the extra space needed because of the false clamp.
These limit switches are inputted directly to the ML circuits.
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