SPRAG TYPE FREEWHEELS

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Description
NBS sprag type freewheels, in their simplest version, are comprised of a series of cams housed in a double cage structure, inserted between two rotating cylindrical surfaces.  The cam profile is positioned in contact with the two rotating surfaces. When the relative rotation occurs in one direction, the cam is not engaged by friction; when the direction is inverted, the friction causes the cams to rotate until these expand and lock the system.
 
Use
NBS freewheels used for overrunning are designed in such a way as to allow a higher overrunning speed, minimising wear and overheating and thereby extending the life of the overrunning freewheel. 
NBS freewheels used as intermittent feed elements rely on the outer ring for intermittent feeding, whilst the inner ring is responsible for one-way transmission. 
If NBS freewheels are used as backstop devices, the overrunning speed can normally only be assigned to the inner ring. In this case, the maximum number of rotations allowed must be strictly respected, and low-viscosity oil is recommended for good lubrication, preferably with an oil circulation system. 
 
 

Typical applications of NBS freewheels for the three different uses, are respectively:
* starting a motor with an auxiliary motor;
* in processing lines with intermittent feed;
* for safety in one-way material or fluid channelling systems;
* etc.
 
KK
KK … 2RS
KK … P
KK … PP
KK … P 2RS
RSBW