One way wedge clutch with reduced freewheel friction

1. A one-way clutch, comprising:

an inner race including a first outer circumference with a plurality of first ramps, each first ramp including:

a respective first face surface orthogonal to an axis of rotation for the one-way clutch or forming a first acute angle with a first line orthogonal to the axis of rotation; and;

a respective first ramp surface with a first end connected to the respective first face surface and a second end more radially inward than the first end;

at least one wedge plate including a smooth second outer circumference and a first inner circumference with a plurality of second ramps, each second ramp including:

a respective second face surface orthogonal to the axis of rotation in the radial direction or forming a second acute angle with a second line orthogonal to the axis of rotation; and;

a respective second ramp surface with a third end connected to the respective second face surface and a fourth end more radially outward than the third end; and,

an outer race including a second inner circumference, wherein:

the outer race is rotatable with respect to the inner race in a first circumferential direction;

for relative rotation of the outer race with respect to the inner race in the first circumferential direction, at least one, but not all, of the respective first face surfaces are in contact with respective second face surfaces; and,

rotation of the outer race in a second circumferential direction, opposite the first circumferential direction, causes the rotation of the outer race to lock to rotation of the inner race.

2. The one-way clutch of claim 1 , wherein the at least one wedge plate includes a radially disposed gap separating first and second ends of the at least one wedge plate such that the at least one wedge plate is wholly discontinuous in a circumferential direction at the gap.

3. The one-way clutch of claim 1 , wherein when the rotation of the outer race is locked to rotation of the inner race, all the respective first face surfaces are free of contact with the respective second face surfaces.

4. The one-way clutch of claim 1 , wherein:

the at least one wedge plate includes a radially disposed gap separating first and second ends of the at least one wedge plate such that the at least one wedge plate is wholly discontinuous in a circumferential direction at the gap; and,

for relative rotation of the outer race in the first circumferential direction, the closer respect first and second face surfaces in contact are to the gap in the first circumferential direction, the less a magnitude of a force opposing rotation of the outer race in the first circumferential direction.

5. The one-way clutch of claim 1 , wherein:

the at least one wedge plate includes:

a first plurality of slots with respective first radially innermost ends opening to the first inner circumference and respective first radially outermost ends enclosed by the at least one wedge plate; and,

a second plurality of slots with respective second radially outer most ends opening to the second outer circumference and respective second radially innermost ends enclosed by the at least one wedge plate; and,

the plurality of first face surfaces forms respective portions of the boundaries of the first plurality of slots.

6. The one-way clutch of claim 5 , wherein the first and second pluralities of slots at least partially overlap in the first circumferential direction.

7. The one-way clutch of claim 1 , wherein:

the at least one wedge plate includes:

a first plurality of slots with respective first radially innermost ends opening to the first inner circumference and respective first radially outermost ends enclosed by the at least one wedge plate; and,

a second plurality of slots with respective second radially outer most ends opening to the second outer circumference and respective second radially innermost ends enclosed by the at least one wedge plate;

for relative rotation of the outer race with respect to the inner race in the first circumferential direction, a circumferential width of a first slot with a boundary partially formed by a respective first face surface in contact with a respective second face surface is greater than a respective circumferential width of a first slot bounded by a respective first face surface not in contact with a respect second face surface.

8. The one-way clutch of claim 1 , wherein for relative rotation of the outer race in the first circumferential direction, the outer race rotates relative to the at least one wedge plate.

9. A one-way clutch, comprising:

an axis of rotation;

an inner race including a first outer circumference including a plurality of first ramps, each first ramp including a respective first face surface orthogonal to the axis of rotation or forming a first acute angle with a first line orthogonal to the axis of rotation;

at least one wedge plate including:

a second outer circumference;

a radially disposed gap separating first and second ends of the at least one wedge plate such that the at least one wedge plate is wholly discontinuous in a circumferential direction at the gap; and,

a first inner circumference with a plurality of second ramps, each second ramp including a respective second face surface orthogonal to the axis of rotation or forming a second acute angle with a second line orthogonal to the axis of rotation; and,

an outer race with a second inner circumference, wherein:

the plurality of first face surfaces is at least partially aligned with the plurality of second surfaces in a circumferential direction;

for relative rotation of the outer race with respect to the inner race in a first circumferential direction:

at least a portion of the second outer circumference is in contact with the second inner circumference;

at least one, but not all, of the first face surfaces are in contact with respective second face surfaces; and,

the closer respective first and second face surfaces in contact are to the gap in the first circumferential direction, the less a magnitude of a radially outward force exerted by the at least one wedge plate on the outer race; and,

rotation of the outer race in a second circumferential direction, opposite the first circumferential direction, causes the rotation of the outer race to lock to rotation of the inner race.

10. A one-way clutch, comprising:

an axis of rotation;

an inner race including a first outer circumference including a plurality of first ramps, each first ramp including a respective first face surface orthogonal to the axis of rotation or forming a first acute angle with a first line orthogonal to the axis of rotation;

at least one wedge plate including:

a second outer circumference;

a radially disposed gap separating first and second ends of the at least one wedge plate such that the at least one wedge plate is wholly discontinuous in a circumferential direction at the gap; and,

a first inner circumference with a plurality of second ramps, each second ramp including a respective second face surface orthogonal to the axis of rotation or forming a second acute angle with a second line orthogonal to the axis of rotation; and,

an outer race with a second inner circumference, wherein:

the plurality of first face surfaces is at least partially aligned with the plurality of second surfaces in a circumferential direction;

for relative rotation of the outer race with respect to the inner race in a first circumferential direction:

at least a portion of the second outer circumference is in contact with the second inner circumference;

at least one, but not all, of the first face surfaces are in contact with respective second face surfaces; and,

the closer respective first and second face surfaces in contact are to the gap in the first circumferential direction, the less a magnitude of a force opposing rotation of the outer race in the first circumferential direction; and,

rotation of the outer race in a second circumferential direction, opposite the first circumferential direction, causes the rotation of the outer race to lock to rotation of the inner race.