
BA 5846 en 05/2015
1
3
7
2
x
min.
4
5
6
Fig. 14:
Torquelimiting backstop
1
Outer ring
2
Inner ring
3
Cage with sprags
4
Shaft (adapter flange)
5
Locking wire
6
Lead screw with compression spring
7
Friction lining
The torquelimiting backstop is attached to the gear unit by means of an adapter flange to form an oiltight
seal and is integrated in its oilcirculation system.
Note
The locking direction can be changed by turning the cage around. If a change in locking direction is
required, Siemens should always be consulted.
WARNING
Risk of injury through moving plant parts
After having stopped the motor, there is a danger that the load is not safely held in its position and can
run in reverse direction at high speed.
The slipping torque was set at the correct value at the works; it must not be changed.
Note
To safeguard the set slipping torque, the lead screws of the compression springs are secured with
locking wire. The warranty will expire if the locking wire for the screws is missing or has been damaged.
Note
As a rule, the backstop operates without wear. As a precaution, the dimension "x
min.
" must be checked
after each releasing operation (type FXRT only) and then every 12 months.