Instron 300DX, Руководство по эксплуатации

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Chapter 4: Maintenance
78 M47-17027-EN
Inspect and replace the pinion - G1-style crossheads
For frames with G1-style crossheads, a pinion should be replaced if it no longer operates the grip jaws
correctly. For correct operation, the ends of the grip jaws should always be aligned with each other as
they are opened or closed (see
Figure 18 ). To check operation, install a set of grip jaws in the grip
pocket and then operate the crank handle to open and close the grip jaws. Watch the grip jaws as they
open and close, they should maintain correct alignment throughout the motion. If they do not, then
perform the following check to determine why alignment is not being maintained:
1. Remove each grip jaw from the grip pocket and check its rack teeth. If rack teeth are broken, then
this could be the cause for incorrect alignment or operation. Grip jaw may need to be replaced.
2. Visually inspect the pinion. Turn the crank handle and watch the pinion inside the grip pocket (if
necessary use a flashlight to illuminate the pinion). Watch for broken teeth. Some amount of broken
teeth are acceptable, but if it is affecting operation of the jaws, then the pinion will need to be
replaced.
Equipment required
•
An 5 mm hex key (supplied)
Recommended procedure
To install a new pinion, perform the following procedure.
1. Remove the crank handle from the pinion.
2. Loosen, but do not remove, the setscrew that holds the pinion in the crosshead (use hex key). The
setscrew is accessed through a hole in the crosshead. For the tension crosshead, the access hole is
located on the top of the crosshead, toward the front and just above the crank handle. For the
adjustable crosshead, the access hole is located on the bottom of the crosshead, also toward the
front and just below the crank handle.
3. Remove the pinion from the crosshead.
4. Insert the new pinion into the crosshead; be sure to insert the rounded end of the pinion first. The
square end of the pinion (that accepts the crank handle) should be protruding from the crosshead,
see
Figure 19 .
5. Install the crank handle onto the end of the pinion.
6. Tighten the setscrew against the pinion just until seated. Back off the setscrew one-half turn.
Figure 18. Identifying correct alignment of grip jaws - G1-style crossheads.
Incorrect alignment
Correct alignment