Initial
Installation
EN 4161.758.101m – 2018-09
25
Gearbox shift mechanism:
During the gear change, the motor shaft
and/or gearbox output is without load
(unbraked).
Gear changes are effected when the 24 V voltage
is applied to pin 2 and 3. The polarity of the
applied 24 V DC voltage dictates which gear is
engaged.
In 1st gear
=> Pin 2: + / Pin 3:
‒
In 2nd and 3rd gear
=> Pin 2:
‒
/ Pin 3: +
During the gear change, the main spindle motor
should make the shaft osc5° or -5° at a rate
of 1 to 5 rotation direction changes per second.
A larger pendulum motion may lead to damage at
the meshing gears. The gears usually already
mesh at the first rotation direction change, so that
the switchover time is approx. 300 to 400 ms.
In average, this means: n
Mot
= 5°/s = 5° 60/min =
300°/min = 300/360 rpm = 0.83 rpm.
Conversion
Pendulum speed
pendulum rotary motion
Speed
[rpm]
Angle
[°/min]
Time
[sec]
Angle
[°/sec]
0.25 90 3.33 5
0.50 180 1.67 5
1.00 360 0.83 5
2.00 720 0.42 5
3.00 1080 0.28 5
4.00 1440 0.21 5
5.00 1800 0.17 5
The machine optimum is to be determined on the
basis of shift tests in relation to the different
masses and the associated drag torques of the
spindle.
The limit switch signals of S1 – gear 1 (contact 4)
and S2 – gear 2 (contact 6) serve to shut off the
shift unit once the gear change is complete.
After the limit switch signals have been reached,
the shift unit is allowed to be live for a maximum
of 0.5 seconds. The limit switch signals must be
monitored during the operating time.
The limit switches must only be energized with the
control current (0.1 – 0.5 A) and not with the
changeover current (5 A).
If the number of resistors is rather small, a lower
control current may also be used.
The control current for end-position monitoring is
to be set according to length, line and transition
resistance and the number of connection points.
Increased resistance due to corrosion after some
time must be taken into consideration. Switching
of inductive loads by means of the control current
requires it to be wired parallel to the load by a
diode.
If the limit switches detect that a gear is no
longer securely engaged, steps such as
emergency shut-off, etc., must be initiated
through the control system.
Electromagnetic fields can falsify the limit
position monitoring.
Do not route control lines in parallel with
cables for the voltage supply or shield control
lines.
The shift sequence must be monitored. If
necessary, a timer should be used to cancel the
shift sequence after approx. 2 seconds if there is
no limit switch signal (S1/S2). The main spindle
motor cannot be operated until a new shift
command is present.
Rotation direction
changes
