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7. LA31 (MEDLINE® CARELINE® TECHLINETM HOMELINE®)
The LA31 actuator is a very quiet
and powerful actuator designed
for a variety of applications such as
furniture, care or hospital beds.
The standard LA31 actuator is available
for both the HOMELINE®, CARELINE®,
TECHLINE™ and DESKLINE® product
ranges.
Reed-switch:
(Reed-switch gives a number of pulses for each rotation of the motor. These
pulses are used to calculate the piston rod’s position as well as to control
several actuators running in parallel.
Your nearest LINAK dealer can inform the number of pulses per stroke length.
Regarding Reed-switch connection, see Figure 6.10.
Hall
The Hall principle is very similar to the Reed principle. A Hall sensor is based
on a magnet that rotates. Two hall sensors are placed close to the magnet
field. The control box (CB20) can detect whenever the magnetic field
changes direction. The two Hall-sensors are placed close to each other, but
with a small displacement. This distance lead to a timing difference between
the two pulses. Whichever one of them comes first indicates the direction of
movement. Therefore, there will be no error summary (like with the reedswitch) Hall is therefore a very precise system. Hall is not suitable for use in
quick release/freewhelling actuators. . see figure 10
Built-in end-stop circuit
In the actuators mentioned the end-stop switch is part of the actuator
construction. Each time the actuator reaches end-stop position the switch is
activated and the current is cut off.
Quick Release
The quick release function is placed in the piston rod end, in which a
wrappedspring clutch can be loosened by means of turning the spring
housing either by the handle or a cable. Hereafter the inner tube can turn
freely and due to the pressure on the piston rod end from the application,
the inner tube will rotate and thus screw itself downwards.
Warning!
If the actuator does not work as described above, the risk of injury due to
squeezing can arise. Therefore, the actuator must immediately be sent for
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