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14 Sept
2006 |
SERVICE BULLETIN
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Number
06-13 |
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Adjustments
and Operation of the Automatic Feed Control
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- Mechanical Adjustments
- Cutoff shoes should be set flush with
the bottom of the feedbox (inset view Fig. 1). If this setting is
maintained, the height gage reading will agree with the actual
distance the cutoff shoes are above the mold.
- With the mold in the raised and
leveled position, 5/8" (A – Fig. 1) above the mold throat
with the feed control cam roller contacting the feed control cam at
the point marked "low" (B – Fig. 1A), adjust the links
(C- Fig. 1 & 1A) until the apron plate is 1/8" above the
mold top plate shown at (D- Fig. 1).
- Manual Control
- If manual control is preferred,
toggle "Auto Feed In Hand". Use the "Auto Feed
Up" and "Auto Feed Down" on the display to your
desired setting. The auto-feed will stay in this position
until moved again. This is also used to set the auto-feed lever
at the midpoint on the gage for using the automatic feature of the
auto-feed. We start the automatic operation here because we want the
auto-feed to have room to adjust up or down.
- Adjust Timers for Auto-feed Control( Up
& Down Movement of Feedbox)
- Timer T4:7. This is the dwell timer.
It is a window that extends beyond Finish Time. If the height pins
come together before the dwell timer times out, there will be no
auto-feed correction. If the height pins come together before the
Finish Timer times out, an auto-feed "up" correction
will occur. And, if the height pins come together after both the
Finish Timer and Dwell Timer time out, an auto-feed "down"
correction will be made.
The recommended preset on this timer is 0040, which equals .4
second. Too much dwell time can actually decrease production and
cause an inconsistent product. Too little dwell time will cause the
auto-feed to be constantly searching and cause undue wear on the
mechanism.
- Timer T4:10. This is the
"Auto-Feed Correction Time". It controls the amount of
movement of the auto-feed mechanism during one "up" or
"down" correction with the "Auto Feed In Auto".
The recommended preset of 0010 or .1 second will cause an adjustment
equal to 1/16 inch or ½ of one gradation. More time on this timer
will cause an over-correction and the auto-feed will again be
"hunting".
- Toggle the "Auto-Feed In
Auto". Adjust Finish Timer T4:1 to 0120, which is 1.2
seconds. Place a rag over one lower height stop. This will
simulate too much material in the mold. Run the machine
automatically until it stops with the head down. When the Finish
Timer and Dwell timer time out, the auto-feed will adjust
"down" ½ of one gradation or 1/16".
- Stop the machine and remove the rag
from the height stop. Run the machine automatically with no
material. The height pins will come together before the Finish
Timer times out and the auto-feed will adjust "up" ½ of
one gradation or 1/16".
- Timer T4:8. This controls the amount
of movement of the auto-feed mechanism with the "Auto Feed In
Hand".
The above procedure also
applies to the autofeed automated cutoff bar (Fig. 2), except there is no
height gauge as shown in Figure 1. The autofeed cam is mounted to the rear
of the feedbox which eliminates the need to disconnect the autofeed
linkages for certain height changes and allows the feedbox to always
remain level.
The auto-feed can be looked at
as a "Quality control" system. A concrete unit requires a
certain amount of material and a certain finish time for proper density
and texture. The automatic feed will attempt to maintain this through the
amount of feed in the mold. If the concrete batches remain
consistent, the automatic feed will maintain consistent.
However, it will not
compensate for batches that are too wet or too dry!
If batch consistency
changes due to an admix not getting in the batch or a material gradation
change, the system may not have enough adjustment to compensate for this.
In this event, the cause of the batch change must be determined. It may be
necessary to lower or raise the Feed Timer T4:0 preset in order to
compensate until the batch inconsistency can be corrected.
Feed times and finish times
will vary from material to material and from mold to mold. These will have
to be determined through experience and it is important that records of
this are maintained, so that values of this can be used as a starting
point the next production run. This will help in maintaining production
levels and maintaining a consistent quality product.
The Delay Timer T4:2 may have
to be changed from product to product. This value is important in
preventing crushing and cracking. During the finish time the pallet
receiver rubbers are compressed and this compression must be relieved
prior to stripping. Depending on materials, finish times, and product
densities, this value must also be recorded as a starting point for future
production runs. Generally .1 to .5 seconds is sufficient but in certain
instances, this may have to be increased.
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Figure 3. Graphic Example of Automatic Feed Control
Timers and Movements
SAFETY BULLETIN
This notice is issued to advise you that some previously
accepted shop practices may not be keeping up with changing Federal and
State Safety and Health Standards. Your current shop practices may not
emphasize the need for proper precautions to insure safe operation and
use of machines, tools, automatic loaders and allied equipment and/or
warn against the use of certain solvents or other cleaning substances
that are now considered unsafe or prohibited by law. Since many shop
practices may not reflect current safety practice and procedures,
particularly with regard to the safe operation of equipment, it is
important that you review your practices to ensure compliance with
Federal and State Safety and Health Standards.
IMPORTANT
The operation of any machine or power-operated device
can be extremely hazardous unless proper safety precautions are strictly
observed. Observe the following safety precautions:
Always be sure
proper guarding is in place for all pinch, catch, shear, crush and nip
points.
Always be sure
that all personnel are clear of the equipment before starting it.
Always be sure
the equipment is properly grounded.
Always turn the
main electrical panel off and lock it out in accordance with published
lockout/tagout procedures prior to making adjustments, repairs, and
maintenance.
Always wear
appropriate protective equipment such as safety glasses, safety shoes,
hearing protection and hard hats.
Always keep
chemical and flammable material away from electrical or operating
equipment.
Always maintain
a safe work area that is free from slipping and tripping hazards.
Always be sure
appropriate safety devices are used when providing maintenance and
repairs to all equipment.
Never exceed
the rated capacity of a machine or tool.
Never modify
machinery in any way without prior written approval of the Besser
Engineering Department.
Never operate
equipment unless proper maintenance has been regularly performed.
Never operate
any equipment if unusual or excessive noise or vibration occurs.
Never operate
any equipment while any part of the body is in the proximity of
potentially hazardous areas.
Never use any
toxic flammable substance as a solvent cleaner.
Never allow the
operation or repair of equipment by untrained personnel.
Never climb or
stand on equipment when it is in operation.
It is important that you review Federal and State Safety
and Health Standards on a continual basis. All shop supervisors,
maintenance personnel, machine operators, tool operators, and any other
person involved in the setup, operation, maintenance, repair or
adjustment of Besser-built equipment should read and understand this
bulletin and Federal and State Safety and Health Standards on which this
bulletin is based. |
