Iv. design considerations – Warner Electric Blade Brake Clutch Application Guide User Manual
Page 3
2. Shoulder Mounting
A shoulder mounting
configuration is shown
(Figure 2). The inner race
of the top plate bearing is
in contact with a shaft
shoulder, spacer, or traction
drive pulley. Clearance must
be maintained between the
end of the crankshaft and the
bottom of the bore
(2mm + 0 -1mm). With this
style of mounting the
shoulder runout should be
held to a maximum of 0.001
inches (0.025mm) and the
parallelism across a spacer or
ground drive pulley should
also be held to a maximum of
0.001 inches (0.025mm). Ground drive must be
chamfered to clear the radius of the crankshaft.
Pulley machining and chamfer to be done in one
chucking.
B. Mounting Bolt Torque
The mounting bolt not only retains the BBC on
the crankshaft but also generates clamping
force to prevent fretting corrosion between
internal BBC components.
3
Warner Electric • 800-825-9050
P-1319-WE • 819-0465
Figure 2
Blade Mounting Hub
Ball Ramp Actuation System
Replaceable Sealed Ball Bearings
Mounting Bolt
Removal Thread for Disassembly
Internal Brake Return Spring
Clutch/Brake Spring
Clutch/Brake Friction Material
Brake Actuation Spring
Attachment Point
Brake Anti-rotation Arm
Clutch Actuation Cable
Attachment Point
Mower
Blade
BBC-II
IV. Design Considerations
A. Mounting
Blade Brake Clutches are typically mounted
directly to the engine crankshaft. BBCs are
available in a shaft end or shoulder mounting
configurations.
1. Shaft End Mounting
A shaft-end mounting
configuration is shown in
figure 1. The end of the
engine crankshaft bottoms
in the bottom of the bore
in the BBC. With this type
of mounting there must be
clearance between the
BBC hub and the ground
drive pulley. The runout of
the end of the engine
crankshaft should be held
to a maximum of 0.001
inches (0.025mm) to
minimize the runout of the
blade.
Figure 1