Hyd-Mech H28A-120, Руководство по обслуживанию и запасным частям

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3.16
If the display does not read as specified:
- Check the encoder pinion gear to be sure it can run smoothly down the rack and that the gear and rack teeth
engage over the entire travel of the shuttle.
- Check that the pinion gear is tight on the encoder shaft.
- Check the encoders cable connections, a loose connection could easily cause this concern.
- Remove the encoder from the machine and check that the shaft can rotate freely. There should be no binding or
rough spots felt when spinning the shaft. Plug the encoder cable into the encoder, clear the length display and rotate
the shaft as closely as possible to one revolution. The display should ready 3.142” (positive or negative depending on
the direction you rotated). Repeat this test 3 or 4 times, spinning the shaft several times between tests.
CONSISTENT INACCURACY (make sure the blade kerf value is correct)
Change the “ACTUAL POS” parameter to YES. This will make the PLC show actual shuttle travel in AUTO
With no material in the machine:
1. Program JOB 1 for 2 pieces of 5” in length. JOB 2 for 2 pieces of 10” in length and JOB 3 for 2 pieces of one
complete shuttle stroke length.
2. Enter JOBS 1 to 3 into the QUEUE.
3. Record measurements on the display each time the shuttle vise reaches the target length and closes. It should equal
the required length plus the programmed kerf. Check that this measurement is ± .002” for each length.
If the overshoot / undershoot is very inconsistent, it could be related to an incorrect shuttle cushion period. This may
be caused by “DECEL DIST” parameter being set to low, defective fast or reverse output relays on the PLC, or the
hydraulic cushion valve (located at the hydraulic manifold) may be faulty.
LINEAR INACCURACY (not valid for machines with linear encoder)
- Load machine with a piece of stock for test cutting.
- Open the parameters screen.
- Initiate the length calibration procedure.
- Re-enter the new “ACT LTH” (actual length) value.
- Re-cut test lengths and check if accuracy is satisfactory.
Note:
Linear inaccuracy may be corrected in two ways, by using the length calibration as described or by adjusting the LTH
CONST as follows:
Load the machine with a piece of stock for test cutting
Program he PLC to cut two pieces of 1”, 12” and a length equal to a shuttle and a half of the machine being checked.
Make the cuts and measure as accurately as possible.
Using the formula provided, calculate the new parameter “LTH CONST”
Formula for determining new parameter “LTH CONST”
Measured length ÷ programmed length x existing constant = new “LTH CONST”
i.e. Programmed length =1.00” Measured Length =.99” -.001”
=12.00” =11.988” -.012”
=60.00” =59.940” -.060”
Existing parameter for LTH CONST = 0.001256
11.988 ÷ 12.00 x .0012566 = 0.001255
The new parameter LTH CONST value would then be 0.001255. This value should be entered and the test repeated.
Adjust the parameter as necessary.