Drive Clutch; Principles Of Operation - Toro Workman 1100 Service Manual

Drive Clutch

1
1. Fixed sheave
2. Moveable sheave
3. Spider assembly
Principles of Operation (Fig. 8)
The operation of the drive clutch is affected by engine
shaft speed. With the engine not turning, the drive belt
rests low within the clutch sheaves as the pressure of
the spring holds the sheaves apart. As the engine in-
creases in speed, the cams attached to the moveable
sheave move outward as they spin about the engine
drive shaft. The outward movement of the cams presses
against the rollers and overcomes spring pressure
through the spider assembly, which forces the move-
able sheave closer to the fixed sheave. This inward
movement of the sheave engages the drive belt.
Drive Train
2
5
8
Figure 8
4. Cover
5. Washer
6. Plastic cap
Page 5 – 8
7. Spring
8. Cam weight
9. Roller
With increasing engine speed, the moveable sheave
continues to move inward, which forces the drive belt to
ride towards the outer diameter of the clutch sheaves.
When engine speed is decreased, the cams exert less
force on the rollers and thus the spring. The spring pres-
sure overcomes the force of the cams, and shifts the
moveable sheave away from the fixed sheave. The
drive belt disengages from the clutch sheaves at a point
where the force of the spring is greater than that of the
weights.
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4
6
7
9
Workman 1100/2100/2110
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