Toro Multi Pro 1200 - Driven Clutch

Multi Pro 1200/1250 Page 7 -- 5 Drive Train
Driven Clutch
Principles of Operation (Fig. 4)
The operation of the driven clutch is affected by load.
When the vehicle is stopped, the CVT drive belt is held
at the outer diameter of the driven clutch sheaves from
thepressureofthes pringpushingthemoveablesheave
against the fixed sheave and away from the fixed cam.
A fixed cam on the moveable sheave rotates on a pair
of rollers in the fixed sheave base to allow a low friction
movement of the moveable sheave.
Once the drive clutch (engine mounted) starts rotating,
thedrivebeltalsostartstorotate.Withincreasingspeed
of the drive clutch, the belt begins to climb to the outer
diameterofthedriveclutchsheaves.Thisincreasesthe
tension on the drive belt and forces the driven clutch
moveable sheave to move away from the fixed sheave
against the pressure of the spring. As the belt tightens
and the driven clutch sheaves open up, the drive belt
rides lower in the driven clutch sheaves.
With increased load from the transaxle and/or spray
pump,thecamresistsforwardmovementrelative tothe
moveable sheave and drive belt. Torque from the drive
beltand springpressure movesthemovablesheaveup
therampof the fixedcam.The drive beltbecomesposi-
tioned closer to the outer diameter of the driven clutch
sheaves to respond to the load increase.
1. Moveable sheave
2. Fixed sheave
3. Spring
Figure 4
1
2
3
1. Pump drive clutch
2. Driven clutch
3. Engine
4. Steering pump
5. Drive clutch
6. Pump drive gearbox
Figure 5
2
3
1
4
5
6
Drive Train