Side Shift, Fork Positioner And Clamp Attachments - Komatsu AX20 Operation & Maintenance Manual

19.5

SIDE SHIFT, FORK POSITIONER AND CLAMP ATTACHMENTS

19.5.1 INSTALLATION/ASSEMBLY
The side shift, fork positioner and clamp attachments all have a common method of installation/assembly as
follows:
1. Before installing, inspect the truck carriage to make sure that the locating notches along the top of the truck
carriage are undamaged and that there are no obstructions on the faceplate itself.
2. Place the clamp into an upright position in preparation for mounting it on the truck.
3. Remove the lower mounting hooks from the back of the clamp frame.
4. Attach the two jumper hoses securely to the clamp's check valve before connecting them to the junction block
on the truck carriage.
5. The open line on the top of the valve is the "clamp open" circuit. The line on the side of the valve is "clamp
close" circuit.
6. If the hose junction block is located on the upper portion of the truck carriage, do not connect the jumper hoses
to it until the clamp is mounted on the truck. Lay the hoses over the top of the frame. However, if the junction
block is located on the lower portion or in the center opening of the carriage, and thus nearly inaccessible when
the clamp is mounted, attach the jumper hoses securely before installing the unit.
7. Install the clamp on the truck. It may be lifted onto the truck or simply positioned on the floor (and blocked up
under the frame and arms) or placed on a pallet so that the truck may be driven up and the truck carriage
moved under the upper mounting hooks on the frame. Line up the locating lug on the clamp with the center
notch on the truck carriage. (The carriage can be raised into the hooks at this point). Be careful not to pinch,
twist, or otherwise damage the jumper hoses in mounting. After the unit has been placed on the truck, bolt the
lower mounting hooks into position on the lower clamp frame, firmly securing it to the truck carriage.
8. Attach the hoses to the carriage junction block.
9. It is normal at this point to re-check the hoses from the truck valve to the clamp. Make sure that the hoses are
routed correctly, and that all connections are tight. For best results, there should be as few 90 degree bends,
and other similar flow restrictions, as possible in the hydraulic circuits. Check the mounting hooks to be certain
that the clamp is solidly mounted to the truck carriage.
10. Start the truck. Operate the clamping function several times to remove any air trapped in the system. Before
proceeding to the next step, check to make sure that the retaining nuts on the anchor and rod ends of each
clamp cylinder are tight.
11. Adjust the rate of arm travel. When the clamp is correctly adjusted both arms should close together from full
extension at the fastest possible speed and reach their minimum range at the same moment. The speed with
which the arms close is controlled by two restrictor fittings, one located on each cylinder at the rod end.
To equalize arm travel:
a. Open both restrictor fittings completely by loosening the lock nut and backing out the threaded shaft. The
restrictor is wide open when 1/2 inch of the shaft is exposed above the tightened lock nut. Opening the
valves completely before making the adjustment is important, because the speed of clamp operation is
directly affected by the degree of restriction in the lines. The fittings should be as wide open as possible
with both arms operating at the same speed.
b. Close the arms from their full extension, watching to see which one is closing most rapidly.
c. Close the restrictor fitting on the cylinder controlling the faster arm until both arms are travelling at the
same rate. The clamp will probably have to be opened and closed several times to make this adjustment
accurately.
4. To complete installation, insert a hydraulic pressure gauge into the truck system's test port and adjust the
pressure relief setting. Never exceed maximum operating pressure for this clamp.
19.5.2 REMOVAL
Removal is the reverse of the installation/assembly sequence noting all the safety precautions in paragraph 1.
Ensure that all locking devices are engaged upon assembly of attachment.
19. REMOVAL AND INSTALLATION OF ATTACHMENTS
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