Specifications

ORC SERIES, MODEL S CLUTCHES
ORC Series, Model S
2
BOSTON GEAR
BOSTON GEAR
®
When an overload occurs, the rotor rotates from its
normal position within the housing. At this instant, the
combined compression of the drive and reset springs is
overcome. For a manual reset clutch, the drive pawl is
forced out of its engaged position from the rotor and as it
pivots up, the reset pawl lifts and locks the drive pawl out
of contact with the rotor as shown in Figure 2. The clutch
is then free to rotate until it is reset. For a clutch with the
automatic reset feature, the reset pawl applies pressure
to the top of the drive pawl, holding it in contact with the
rotor as shown in Figure 3.
B. Resetting Instructions
1. Manual Reset
a. After the overload condition has been corrected,
rotate the drive until the rotor keyway is in
alignment with the hole stamped 22 located on the
outside diameter of the housing (see Figure 4).
b. Reset the clutch by inserting a hex wrench into the
reset screw shown in Figure 4, and turn the screw
clockwise until the reset pawl releases the drive
pawl. Refer to Table 5 for the proper wrench size.
Note:
Be sure not to use a powered wrench as it may
cause damage to the reset pawl and/or reset
spring!
c. When the drive pawl enters the rotor notch, turn the
wrench counterclockwise until the reset screw has
stopped at its original position, which is
approximately flush with the O.D. of the clutch
housing. This is essential to restore the torque to its
original setting.
2. Automatic Reset
After one complete revolution the drive pawl will
automatically return to its original engaged position.
After the overload condition has been corrected “jog”
the drive until the drive pawl engages with the rotor.
C. Torque Adjustment
The clutch is supplied with a torque selector dial. This dial
makes torque adjustments on the clutch possible. There
are mill marks on the housing near the hole stamped 9 on
the outside diameter of the housing. The mill marks have
stamped values indicating a set, or minimum and
maximum torque (see Figure 5). If a drastic change in
torque is desired, it may be necessary to change springs.
See Section Vl for spring replacement.
1. Increasing the Torque.
a. Disengage the clutch.
b. Turn the torque adjustment screw clockwise until it
is flush with the milled depth of the desired torque
setting and the red scribed lines are in line with
each other.
c. Reset the clutch and check its operation.
2. Decreasing the Torque.
a. Make sure that the clutch is engaged.
b. Turn the torque adjustment screw counter-
clockwise until it is flush with the milled depth of the
desired torque setting and the red scribed lines are
in line with each other.
c. Disengage the clutch and check its operation.
3. See Figure 6 for Limit Switch Actuating Mechanism
adjustment.
Limit Switch Pin
Extended
Reset Pawl
Engages Notch
in Drive Pawl
Manual
Reset Screw
Drive Pawl Locked
Out Of Contact
with Rotor
FIGURE 2 DISENGAGED MANUAL
Limit Switch Pin
Extended
Reset Pawl Holds
Drive Pawl in Contact
With Rotor
Drive Pawl
Disengaged From
Rotor
FIGURE 3 DISENGAGED AUTOMATIC
(Stamped 9)
Actuating
Pin
Drive Pawl
(Stamped 26)
Drive Spring
(Stamped 8)
Drive Spring Screw
Rotor Setscrew
Access Screw
(Stamped 22)
(Stamped 20)
Rotor
Reset Pawl
Housing
Reset Spring
Reset Spring Screw
FIGURE 4 – CLUTCH INTERNAL COMPONENTS
Torque Adjusting Screw
Square Wrench Socket
Milled Depth
For Max. Torque
Milled Depth For
Set or Min. Torque
Reset Spring
Disc
Lock Screw
Maximum Torque
Limit Stop Pin
FIGURE 5