Multi function torque converter with axially stacked clutches and method of controlling hydraulic pressure and flow

1. A torque converter comprising:

a turbine;

a single impeller;

a seal;

a first clutch;

a second clutch including a piston plate connected to the turbine so as to rotate with the turbine, the piston plate arranged to open or close the second clutch; and,

a plate disposed in a torque transmission path from a cover for said torque converter to said first and second clutches and including an end in direct contact with the seal, wherein said first and second clutches each comprise said plate.

2. The torque converter of claim 1 further comprising an impeller and an output hub and wherein said first clutch comprises an impeller clutch arranged to transmit torque from said cover to said impeller and wherein said second clutch comprises a torque converter clutch arranged to transmit torque from said cover to said output hub.

3. The torque converter of claim 2 wherein said impeller clutch comprises a first portion exclusive of said plate, said torque converter clutch comprises a second portion exclusive of said plate, and said plate is axially disposed between said first and second portions.

4. The torque converter of claim 1 further comprising a damper assembly disposed in said torque transmission path.

5. The torque converter of claim 4 wherein said plate disposed in the torque transmission path is connected to said damper assembly.

6. A torque converter comprising:

a single impeller;

a first cover;

an impeller clutch including a first piston plate, a first plate directly connected to the single impeller, and first friction material axially disposed between the first piston plate and the first plate; and,

a torque converter clutch including the first piston plate, a second piston plate connected to an output hub for said torque converter, and second friction material, wherein:

when the impeller clutch is open, the single impeller is rotatable independent of rotation of the first cover;

the first piston plate is displaceable such that the first friction material is in contact with the first plate and the first piston plate; and,

the second piston plate is displaceable such that the first and second piston plates are in contact with the second friction material.

7. The torque converter of claim 6 wherein said first piston plate is displaceable to at least partially enable closing of said impeller clutch and said torque converter clutch.

8. The torque converter of claim 6 further comprising a damper assembly rotationally connected to said first piston plate and said cover.

9. The torque converter of claim 6 further comprising a second cover for the single impeller; a turbine; a third cover for the turbine; a fourth cover connected to the first cover; a first chamber including said turbine and said single impeller and at least partially defined by said first plate, said second piston plate, and said third cover; a second chamber at least partially defined by said first and second piston plates; and a third chamber at least partially defined by said second and fourth covers, said first piston plate, and said first plate, wherein in a torque converter mode, pressure for fluid in said second chamber is arranged to be greater than pressures for respective fluids in said first and third chambers, and said first and second chambers are in fluid communication.

10. The torque converter of claim 9 wherein said fluid in said second chamber is arranged to flow through said first chamber to cool said turbine and impeller.

11. The torque converter of claim 10 wherein said flow of fluid from said second chamber to said first chamber bypasses said first friction material.

12. A torque converter comprising:

a damper assembly connected to a cover for said torque converter and including a flange passing through a plurality of springs and first and second side plates axially bracketing the flange;

an impeller clutch connected to an impeller and including first friction material;

a torque converter clutch connected to an output hub for said torque converter and including second friction material; and,

a plate included in said impeller clutch and in said torque converter clutch and connected to said damper assembly, wherein the plate is free of engagement with the plurality of springs, said impeller clutch comprises a first portion exclusive of said plate, said torque converter clutch comprises a second portion exclusive of said plate, said plate is axially disposed between said first and second friction material, and the plate includes an end disposed radially inward of the plurality of springs.