CENTRIFUGAL BALANCE CLUTCH CONSTRUCTION/OPERATION


BHE051301026T11

Construction

• Centrifugal balance clutch chambers are installed opposite the clutch chambers in the low and high clutches. The centrifugal balance clutch chambers are constantly filled with ATF from an exclusive hydraulic passage of the oil pump.

1
Centrifugal balance clutch
2
Conventional clutch
3
Seal
4
Clutch chamber
5
Clutch piston
6
Clutch pressure
7
Balance chamber
8
Clutch drum
9
Clutch
10
Seal plate
11
Lubrication passage
12
Piston check ball
13
Spring

Operation

When clutch pressure is not applied

• When the clutch drum rotates, centrifugal force acts on the residual ATF in the clutch chamber to push against the piston. However, centrifugal force also acts on the ATF filling the centrifugal balance clutch chamber to push back the piston. As a result, the two forces are eliminated and the piston remains stationary, thus preventing clutch engagement.

When clutch pressure is applied

• When clutch pressure is applied to the clutch chamber, the clutch pressure overcomes the oil pressure and spring force in the opposite centrifugal balance clutch chamber, and pushes the piston to engage the clutches. Because the centrifugal force acting on the clutch pressure in the clutch chamber is canceled by another centrifugal force acting on the ATF filling the centrifugal balance clutch chamber, the influence of the centrifugal force created by the clutch drum revolution speed is eliminated. As a result, stable piston pushing force is obtained in all rotation ranges, and smoother shifts can be made.

1
Centrifugal balance clutch
2
Previous clutch
3
Two forces are eliminated
4
Centrifugal hydraulic pressure of piston chamber
5
Clutch pressure
6
Piston
7
Centrifugal hydraulic pressure of balance chamber
8
Spring force
9
Changes according to rotation speed of clutch drum
10
Piston pushing force
11
Increased clutch pressure (centrifugal hydraulic pressure)
12
Drum revolution speed
13
Piston pushing force required to obtain shift quality
14
Centrifugal pressure