AT-38
< SERVICE INFORMATION >
A/T CONTROL SYSTEM
A centrifugal cancel housing is provided to cancel the clutch housing pressure. The centrifugal cancel housing
is always filled with ATF from the dedicated fluid passage of oil pump.
When Clutch Pressure Is Not Applied
As high clutch drum rotates, a centrifugal force applies to the remaining ATF in clutch housing to push high
clutch piston. However, on the other hand, the centrifugal force also applies to ATF filled in centrifugal cancel
housing, resulting in a force that pushes high clutch piston back. Consequently the high clutch piston does not
move because both forces cancel each other, and thus high clutch is prevented from dragging.
When Clutch Pressure Is Applied
Clutch pressure that applies to clutch housing overcomes the fluid pressure and spring force of the opposing
centrifugal housing to push high clutch piston, and high clutch is engaged. At this time, the centrifugal force
caused by the revolution speed of high clutch drum has no impact any more since the centrifugal force that
applies to the clutch pressure of clutch housing is canceled by the centrifugal force that applies to centrifugal
cancel housing. As a result, high clutch piston pressing force is always stable in all revolution speeds, and
thus smooth shifting characteristics are achieved.
SCIA7986E
SCIA6833E
Revision: January 20102010 Versa