Pressure plates ( hat/ clutch/ donut/ pressure-plate ) |
|
![](http://darkside.ca/files/clutch-images/hppressure_plates.jpg)
|
Automotive Street/Strip
There are 3 Basic types of pressure plates. |
diaphragm-type – static pressure (center) street /strip – low pedal pressures |
spring-type |
– Borg & Beck – static pressure (right) street/strip |
– Long – static pressure and Centrifugal (left)competition / very adjustable
springs force pressure plate against discs – Springs provide all or most of locking force,centrifugal force added by arms extending out of the end of arms ncreases the force as engine RPM goes up
this example is a 2 disc, aluminum flywheel , chevy starter ring, long style cover, adjustable springs (threw holes in cover ), adj centrifugal force (by adding bolts nuts and washers to 3 arms)
|
|
![](http://darkside.ca/files/clutch-images/mccleod.jpg) |
![](http://darkside.ca/files/clutch-images/cent_clutch2.jpg) |
Exceptions
In auto racing there is always exceptions
this is a diaphragm clutch with centrifugal arms added ?
|
|
Pressure plates – Slider Clutches
|
If it is desirable to program the clutch forces to engine RPM (Drag Racing) then reducing (or eliminating) the springs (static) and using the centrifugal weighted arms for most or all clamping forces is an option. In drag racing we call this a slider clutch . at an idle the clutch may not even provide enough force to move the vehicle , sometimes a clutch pedal isn’t needed , like an automatic/converter equipped car. Sometimes described like a snowmobile centrifugal clutch
|
|
Pedal
springs force pressure plate against discs, needs a pedal to launch race car, but force primarly centrifugal
|
|
Centrifugal
spring hold pressure plate away from discs, may not need a pedal to launch race car, but force only centrifugal
|
![](http://darkside.ca/files/clutch-images/clutch-1.jpg) |
Multi Stage
Note :
– arms installed are 6 base arms same length (height from release bearing)
this makes it a single stage possibly an A fuel or Nostalgia
– arms on left can be added in empty slots on cover, or even replace base arms
this would be added to clamping force of pressure plat as release bearing is moved back by hydraulic/pneumatic clutch management system (keep in mind there will be an
imbalance if arms aren’t kept equal weight – which is impossible so bye bye rear bearing)
|