FLENDER B3 A Series - Gear Units with Auxiliary Drive and Torque-Limiting Backstop

Principle of operation
The overrunning clutch as centrifugally-operated sprags. When the main gear unit rotates with
the speci󹪝ed direction of rotation, the inner ring with the sprags rotates, while the outer ring
remains stationary. Above a certain speed the sprags disengage, and the overrunning clutch
operates without any wear.
When the auxiliary unit drive motor is used as drive via the outer ring, then the overrunning
clutch is also driven; this means that the main gear unit is slowly rotated in the selected direction
of rotation. In this case, the input shaft of the main gear unit and the main motor simultaneously
also slowly rotate when a 󹪞exible coupling is used between the main motor and gear unit.
Note
Electrically interlock the main motor and the auxiliary drive motor so that only one of the two
motors can be switched on.
Note
When driven by the auxiliary drive, then the input shaft of the main gear unit also slowly rotates.
It is not permissible that this rotary motion is prevented. A brake located on the drive side in the
main drive must be opened when driven by the auxiliary drive.
Oil supply for the overrunning clutch
The overrunning clutch is located in an intermediate 󹪞ange and has a separate oil space. When
the main gear unit is serviced and its oil changed, then the overrunning clutch is also serviced
and its oil changed at the same time.
3.19.3 Gear units with auxiliary drive and torque-limiting backstop
If, for gear units with auxiliary drive, a torque-limiting backstop (Page 32) is used, then the
sliding torque is already set to the correct value in the factory. Readjustment or checking when
commissioning the system is not required.
WARNING
Severe injury when the auxiliary drive explosively breaks apart
If the overrunning system develops a fault, due to the high resulting speeds, the auxiliary drive
can suddenly break apart explosively.
Further, there is a risk that after the main motor is switched o󹪜 the load cannot be securely kept
in position, and that it can accelerate in the reverse direction.
The speed monitoring function is mandatory for safety reasons.
Description
3.19 Auxiliary drive
Assembly and operating instructions A5051en
Edition 06/2020 49