Balluff BML-M0 Serie Betriebsanleitung Seite 59

BML-M0 _ -... / BML T _ _ -...
Magnetic Tape – Magnetic Encoder System
6
Accessories (continued)
6.7 Mounting with downholder
BAM MC-ML-062-001-4
When mounting long magnetic tapes on carriers that are
not made of steel, temperature fluctuations may cause the
adhesive tape to tear off at the ends of the magnetic tape.
This is due to the different expansion coefficients. These
should be considered when selecting carriers.
The following example is intended to assist in
interpretation:
A 5-meter-long magnetic tape is mounted on an aluminum
carrier: At a temperature difference of 30 K between
mounting and operation, the magnetic tape is extended by
1.5 millimeters. The aluminum carrier is extended by 3.5
millimeters. Each end shortens the magnetic tape by 1
millimeter in relation to the aluminum carrier.
For the magnetic tape, an expansion coefficient of 10.5 ×
10 K can be calculated.
-6 -1
The adhesive tape can partially compensate for expansion
and prevent tearing. Depending on the length of the
magnetic tape and the difference between the mounting
and operating temperatures, separation may occur at the
ends of the tape. In case of fluctuations smaller than 3.5
millimeters, two BAM MC-ML-062-001-4 washers
(downholders) can be used to maintain the functionality of
the position measuring system. Mounting the washers at
the ends of the magnetic tape prevents a detaching
magnetic tape from damaging the sensor head when it
passes over.
10
Fig. 6-7: Downholder BAM MC-ML-062-001-4
Fig. 6-8:
Before mounting, at least 4 millimeters of the magnetic
layer must be removed from the ends of the magnetic tape
so that the steel of the carrier tape is bare. To do this,
carefully remove the magnetic layer by milling or with a
scalpel.
The washers are mounted at the calculated distance, so
that in the event of temperature fluctuations, on the one
hand, the magnetic tape is not compressed, and on the
other hand, the washer covers the end.
The set includes two self-tapping screws (M2, 5x6, drive
TX8), so that the mounting hole only needs to be pre-
drilled. DIN 7500-2 recommends a core hole diameter of
2.3 millimeters. A first assembly can be done with these
screws. If it is necessary to disconnect the connection, it is
recommended to use the standard screws (drive, Phillips
screws), which are also included in the set, for further
assembly.
1.4
0.5
M2.5x6
Screw mounting
Additional documents can be obtained online
at www.balluff.com or by e-mailing
service@balluff.de.
english
≥ 4
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