Mounting
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5.1
Cam Followers
For
greatest rigidity and strength, the end plate should be drawn up snugly
against a boss or other flat surface of the housing. The tables on pages
5 throughout 27 list maximum recommended clamping torque for lubricated
threads, which is the normal condition. Use up to twice the listed torque
for completely dry threads.
The
housing bore should be drilled and reamed to the recommended tolerance.
If a greater tolerance is needed, it should be added to the plus side
to prevent cam follower damage during assembly. If the cam follower
stud fits tightly into the housing bore, use an arbor press and apply
pressure against the central portion of the flange. Never press against
the rim of the flange or the outer ring.
Although
wide blade screwdrivers may be used to hold cam followers during assembly,
rounded tools conforming to the slot are preferable to avoid plastic
deformation in the slot area.
RBC
offers a convenient socket (W suffix) for hex wrenches to provide a
more substantial grip, especially for 'blind hole' applications. (Note
this series can only be relubricated from the thread end or through
the housing).
5.2
Eccentric Cam Followers
Eccentric
cam followers are used when there is a need to make height adjustments
between the cam follower and the track. By simply turning the entire
cam follower inside the housing it is possible to adjust the distance
between the cam follower and the track by twice the eccentricity. However,
due to the mechanical advantage that the eccentricity provides, it is
inadvisable that the cam follower be adjusted over this entire range.
A very
large force can be exerted on the track for a small applied adjusting
torque as the eccentricity of the cam follower approaches ±90 degrees
from a starting position parallel to the track, in the housing. Adjustments
should be limited to ±45 degrees and the resulting preload should not
exceed 10% of the cam followers capacity.
The
following equation can be used to find an appropriate adjusting torque.

|
(13) |
where |
T = appropriate
adjusting torque [lbf]
C = cam followers dynamic capacity [lbf]
e = eccentricity of cam follower [in] |
|
Example 5 Cam-centric
cam follower S48LWX has a dynamic capacity of 4,600 lb, and an eccentricity
of 0.03 in. Determine the appropriate adjusting torque.
Solution:

5.3 Yoke Rollers
RBC yoke rollers
correspond in many respects to the same size cam follower, except they
are mounted on a pin for use in yoke type applications for greater shock
resistance.
Yoke rollers should
be clamped axially or mounted within closely fitting side rails to prevent
displacement of the end plates. For applications with heavy loads, it
is recommended to heat treat the pin and use a press fit for the inner
ring. A soft pin and light press or push fit are sufficient for lightly
loaded applications. When press fitting a yoke roller, pressure should
be applied centrally and uniformly against the end plate, never against
the outer ring.
The pin should have
a suitable lead-in chamfer or radius to prevent scoring and to hold
the mounting force to a minimum.
5.4 Caged Roller
Followers
Caged roller followers
can operate directly on a hardened and ground shaft (HRc 58 min, 16
rms min surface finish) or can be used with matching inner rings. Operating
without an inner ring yields the largest possible shaft diameter with
greatest strength and rigidity. Axial guidance must be provided by the
application. It is recommended to use hardened steel or bronze thrust
washers with radial lubricating grooves as needed.
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