Suma Precision Machinery

Model

Torque
Capacity
(N·m)

Max.
Overrunning(r/min)

Bore Size

A

B

C

PCD

E

F

S

H-MNo.of
Tapped Holes
×Size×Pitch

Lubrication
Filler Plug
Size×Pitch

Oil
(mℓ)

Weight
(kg)

Installation and Usage
1. MR Series Cam Clutch is used
for outer race overrun in high-
speed applications.
2. For attaching a pulley, a gear, or
a sprocket to the clutch, insert
the clutch into the hub of the
said device, and screw the bolts
(high tension) into the tapped
holes on the clutch. The
tolerance of the bore hub should
be H6 or H7 of ISO R773. See
the illustration on this page.
3. Recommended shaft tolerances
are as follows:
4. When mounting the clutch on a
shaft, apply pressure to the
clutch inner race, but never to
the outer race.
5. Allow for a clearance between
the top of the clutch keyway and
the top of the key for pressure
ventilation. A pressure ventilation
hole is provided on the keyway
of the clutch inner race.

Lift-off (Outer race rotation type)
MR Series Cam Clutch is structured
so that the cam rotates together with
the outer race when the outer race
overruns. As shown in the figure, the
spring force (Fs) works to make the
cam come in contact with the inner
and outer races with fixed pressure.
Conversely, the eccentric force (Fc),
which works on the cam when
overrunning, applies a moment in the
direction where the cam does not
contact the inner and outer races.
Accordingly, when the overrunning
speed is increased, the eccentric
force (Fc) increases and the
movement is augmented over the
movement caused by the spring
force. Next, the cam lifts off from the
inner race and loses contact with it.
This phenomenon is called “lift-off.”
In this state, there is no friction on the
cam and it continues overrunning as
long as the bearing lasts.

• See “Information for Selection” on page 77.

• See “Lubrication and Maintenance” on

page 79.