INTORQ BFK455, Руководство по эксплуатации

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Technical data 3
j
| BA 14.0196 | 05/2013
14
The switching status of the spring-applied brake is monitored by one microswitch (16) for each
braking circuit. The associated switchgear rectifies the supply voltage (AC voltage) which is
reduced after a short time while the brake is in the released state. Thus the mean electrical
power of the brake is reduced.
The stator (1) is designed in temperature class F. The temperature limit of the coils (8) is
155 °C. The BFK455 spring-applied brake is designed for a maximum operating time of 60 %
with a reduction of the holding current.
Certificate
Type Characteristic torque [Nm] EC type-examination certificate
BFK455-28
2 x 1100, 2 x 1200
ABV 881/1
2 x 1700, 2 x 1800
2 x 2065
3.1.2 Braking
During braking, the rotor (3), which is axially movable on the hub (4), is pressed against
the friction surface - via the armature plates (2) - by means of the springs (1.2). The
asbestos-free friction linings ensure a high braking torque with low wear. The braking
torque is transmitted between hub (4) and rotor (3) via the splines.
3.1.3 Brake release
In braked state, there is an air gap ”s
L
” between the stator (1) and the armature plate (2). To
release the brake, the coil of the stator (1) is excited with the DC voltage provided. The
magnetic force generated attracts the armature plate (2) towards the stator (1) against the
spring force. The rotor (3) is then released and can rotate freely.
3.1.4 Release monitoring
The spring-applied brake is equipped with one microswitch (16) each per braking circuit
for monitoring the switching status. When the braking circuits are released, the
microswitches (16) change over. This means that the operation of the drive against the
applied brake can be excluded. The microswitches can be connected both as NO and NC
contacts.
For checking the correct functioning of the microswitches, we recommend to check the
switching status (see Tab. 6) both when the brake is released and when the brake is
applied.
3.1.5 Encapsulated design (optional)
This design not only avoids the penetration of spray water and dust, but also the spreading
of abrasion particles outside the brake. This is achieved by:
| a cover seal over the armature plate and rotor.