A wet clutch includes a clutch carrier that encloses a stack of clutch plates and a clutch backing plate. Two sets of alternating slots are provided in the clutch carrier. One set of slots is shallower than the other set and is configured to support the clutch backing plate. The other set of slots is deeper and is configure to support many of the clutch plates. The first set of slots is shallower in order to keep the clutch backing plate from pressing against and partially binding the stack of clutch plates together.
1. A wet clutch for a transmission comprising:
(1) a clutch carrier including a cylindrical portion, the cylindrical portion defining a first plurality of axial slots therein and defining a second plurality of axial slots therein that are shorter than the first plurality of slots;
(2) a gear including a splined hub disposed inside the cylindrical portion;
(3) a stack of clutch plates including
(i) a first set of clutch plates including protrusions configured to engage the first plurality of slots, and
(ii) a second set of clutch plates interleaved with the first set of clutch plates and including splines configured to engage the splined hub; and
(4) a clutch backing plate including protrusions configured to engage the second plurality of slots.
2. The clutch of claim 1 , further comprising a sealing ring disposed on the gear and configured to seal against the clutch backing plate.
3. The clutch of claim 1 , wherein the clutch carrier has a circumference and further wherein the first and second pluralities of slots are disposed in an alternating pattern around the circumference.
4. The clutch of claim 1 , wherein the first plurality of slots includes 3 to 8 slots and further wherein the second plurality of slots includes 3 to 8 slots.
5. The clutch of claim 1 , wherein the first and second pluralities of slots include an equal number of slots.
6. The clutch of claim 1 , wherein different depths of the first and second pluralities of slots insure that at least one clutch plate gap is provided when the clutch is disengaged.
7. The clutch of claim 1 , wherein the cylindrical portion of the clutch carrier has a free end in which the first and second pluralities of slots are formed, and further wherein the free end defines a circumferential ring groove on an inner surface thereof, the clutch further comprising a snap ring disposed in said groove to enclose the first and second pluralities of slots.
8. A clutch for a transmission comprising:
(1) a clutch carrier defining a first plurality of axial slots and a second plurality of axial slots shorter than the first plurality of slots;
(2) a gear including a splined hub disposed inside the clutch carrier;
(3) a stack of clutch plates including
(i) a first set of clutch plates including ears configured to engage the first plurality of slots, and
(ii) a second set of clutch plates interleaved with the first set of clutch plates and including protrusions configured to engage splines of the splined hub; and
(4) a clutch backing plate including ears configured to engage the second plurality of slots.
9. The clutch of claim 8 , further comprising a polymeric sealing ring disposed in a ring groove on the gear and abutting the clutch backing plate.
10. The clutch of claim 9 , wherein the clutch carrier has a cylindrical portion circumference and further wherein the first and second pluralities of slots are disposed in the cylindrical portion in an alternating pattern around the circumference.
11. The clutch of claim 10 , wherein there are from 3 to 8 slots in the first plurality of slots and further wherein there are from 3 to 8 slots in the second plurality of slots.
12. The clutch of claim 11 , wherein the first plurality of slots contains the same number of slots as the second plurality of slots.
13. The clutch of claim 12 , wherein the first and second pluralities of slots are configured to insure that the clutch backing plate never presses against the clutch plate stack when the clutch is disengaged.
14. The clutch of claim 13 , wherein the cylindrical portion of the clutch carrier has a free end in which the first and second pluralities of slots are formed, and further wherein the free end defines a circumferential ring groove on an inner surface thereof, the clutch further comprising a snap ring disposed in said circumferential ring groove to (1) hold the first set of plates in the first plurality of slots and (2) hold the clutch backing plate in the second plurality of slots.