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3. Assembling of clutch, brake
Turn off the power, and make sure rotating elements
are stopped.
Never work while rotating, or it may cause electric
shock or injury. When mounting, dismounting, or
adjusting, turn off the power source, and make sure
the rotating elements are stopped still. At this time,
be careful not to have fingers or hand pinched.
Tighten bolts to specified torque, and lock securely.
Depending on the degree of tightening, the bolts may
be broken to cause injury. Using specified bolt
material, tighten bolts to specified torque, and lock
securely with adhesive, spring washer or the like as
specified. Besides, since the parts composing the
product rotate relatively to each other, the tightened
parts must be fixed securely for the safety of
operation.
The bolt strength and tightening torque are
designated in the specification.
Connect lead wires securely.
Otherwise it may lead to an electric shock.
Connect securely, both electrically and mechanically,
and insulate appropriately.
Be sure to connect a surge absorber parallel to the
exciting coil to cut off the direct current.
Cutting off the current may cause a large surge
voltage, and the surge voltage may deteriorate the
peripheral units.
For this reason, be sure to use a surge absorber,
such as a diode, varistor, and protective resister.
Use wire size suited to current capacity.
If wire of smaller current capacity is used, the
insulating coating may melt down to cause insulation
failure, possibly leading to electric shock, current
leak, or fire.
The specified current of the product is designated in
the specification.
Mount, dismount, and transport with greatest care.
Carrying of a heavy product may cause lumbago or
injury by dropping.
Be careful sufficiently when mounting, dismounting,
or transporting.
In particular, handle the product provided with
eyebolts by using a hoist or the like.
(Note) The hoist operation by using the eyebolts should be done by a
qualified operator.
1) Make sure there is enough clearance when installing the product to prevent
impact and undue force from being applied to the product during assembly
work. Especially, when inserting the output shaft into the shaft on the
machine side, make sure to support the shaft part of the driven member.
2) Use the powder clutch in the regular installation status in which the high-
speed rotation side is located as the input side. (The nameplate indicates
the input side and output side with arrows.)
Install both the clutch and brake so that the shafts become horizontal.
3) For coupling with the load shaft, use an elastic coupling.
4) For pulley coupling, pay attention to the belt tension, and never apply initial
tension more than necessary.
5) For the clutch, use the bolt hole on the fin side to prevent undue force
from being applied to the product and stop rotation of the stator.
If it is completely fixed, the bearing could be damaged.
6) The voltage polarity is not specified.
Fig. 3 Mounting of ZA-A powder clutches (For shaft drive)
Powder
Space
Nut
Elastic
clutch
coupling
Fin
Motor
Bearing
Output
shaft
Bolt
Fin rotation
Enlargement
prevention
plate
4. Operation
Never touch the product during operation.
The rotating elements are exposed outside, and the hand
or part of body may be injured if touching the product.
Install a protective cover, allowing smooth ventilation, so
that the hand or fingers may not be in contact with the
machine during operation, and also a safety mechanism
to stop the rotating elements immediately when the cover
is opened.
Remove eye-bolts after assembly
(ZA-20A
, ZA-20Y
, ZA-40Y)
1
1
Eye-bolts are projecting, and may contact safety cover or
the like to cause breakage or injury. Remove right after
assembling, and then start operation.
Space
If a shock is applied to the clutch during transportation, powder may be
scattered inside the clutch. For this reason, before starting regular operation,
perform running-in while following the procedure below to collect powder into
the powder gap, if necessary.
Fin rotation
1) Running-in procedure
prevention
plate
Never increase the rotating speed more than allowable.
If the rotating speed is raised more than allowable,
vibration increases to cause breakage and scattering of
powder, and it is very dangerous. Rotate within allowable
speed, and install protective cover.
Fix the output shaft to prevent rotation. (If it is difficult to fix the shaft, apply
a heavy load to prevent rotation of the output shaft.)
After that, without flowing the exciting current, rotate the drive member at
approximately 200 r/min for 1 minute, and then set the exciting current to 1/
4 to 1/2 of the rated value. While rotating the drive member, flow the
exciting current for 5 seconds, and then stop flowing the current for 10
seconds. Repeat this cycle approximately 10 times.
2) End of running-in
While the running-in is insufficient, the torque output may be low or the
torque may fluctuate, but as the running-in becomes sufficient and the
powder comes to work effectively, a stable torque corresponding to the
exciting current is produced.
After the running-in, start regular operation.
Depending on the conditions of use, the drive member surface temperature may
rise considerably. Use the product while keeping the surface temperature below
100°C. If the surface temperature exceeds 100°C, relax the operation conditions,
and prevent overheat of the clutch.
The above-described surface temperature is a reference value. Be sure to use the
clutch within the allowable heat dissipation.
(Herein, the surface temperature is mentioned on the basis of the ambient
temperature of 30°C. The allowable ambient temperature range is 0 to 40°C.)
Use thermometer when measuring temperature.
Don't touch directly by hand to avoid burns. Turn off
the power source, and make sure the rotating
elements are stopped still, and measure with
thermometer.
Measure promptly.
5. Torque adjustment
Use within rated torque.
If used over the rated torque, not only the
performance deteriorates, but also mechanical
breakage or injury may be caused. Hence, use with
rated torque. In particular, it must be noted that a
torque over the rating may be cause even if used at
the rated current, and therefore check the current-
torque characteristic, and adjust the exciting current.
(In the course of use, the torque gradually declines,
and therefore in manufacturing, a proper allowance
is considered initially.)
The relation of torque and exciting current is almost proportional as shown
in Fig. 4, and therefore by adjusting the current, the torque can be easily
adjusted.
Set to a proper value in consideration of the finish of the product or
working condition.
Use within the allowable heat dissipation.
If used over allowable heat dissipation, the clutch
may be extremely heated, and the working surface
may be extremely hot and red. As a result, a fire may
be caused. In addition, the performance may be
deteriorated. Be sure to use within the allowable heat
dissipation (refer to Fig. 5).
Fig. 4 Exciting current vs. torque characteristics
(representative examples)
40
ZA-2.5A
1
30
20
ZA-1.2A
1
10
ZA-0.6A
1
0
0.0
0.5
1.0
1.5
Exciting current (A)
300
ZA-20A
1
250
200
ZA-10A
150
1
100
ZA-5A
1
50
0
0.0
0.5
1.0
1.5
2.0
2.5
Exciting current (A)
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