Brake rotor and method of manufacturing the same

1. A brake rotor for an automotive vehicle braking system comprising:

a brake rotor hat having a generally circular mounting portion, a generally cylindrical wall connected to the mounting portion and being generally symmetrical about an axis, and first and second pluralities of fingers extending radially outward from the wall;

wherein each of the first plurality of fingers and each of the second plurality of fingers has a respective terminal end portion;

wherein the terminal end portions of the first plurality of fingers are coplanar about a first plane;

wherein the terminal end portions of the second plurality of fingers are not coplanar about the first plane, and are coplanar about a second plane that is parallel with the first plane;

wherein each of the fingers includes respective torque transmission surfaces that are positioned such that a force exerted on any one of the torque transmission surfaces urges the rotor hat to rotate about the axis;

a rotor cheek that contacts each of the torque transmission surfaces; and

an annular member disposed between the first plane and the second plane.

2. The brake rotor of claim 1 ,

wherein the first plurality of fingers limits movement of the annular member in a first axial direction, and the second plurality of fingers limits movement of the annular member in a second axial direction.

3. The brake rotor of claim 2 , wherein each of the first plurality of fingers defines a respective stop surface that faces the second axial direction;

wherein each of the second plurality of fingers defines a respective stop surface that faces the first axial direction;

wherein the annular member is disposed such that axial movement of the annular member in the first axial direction is restricted by contact between the annular member and the stop surfaces of the first plurality of fingers, and axial movement of the annular member in the second axial direction is restricted by contact between the annular member and the stop surfaces of the second plurality of fingers.

4. The brake rotor of claim 3 , wherein the rotor hat is formed from a single piece of metal.

5. The brake rotor of claim 4 , wherein the metal is stainless steel.

6. The brake rotor of claim 1 , wherein the annular member includes a first surface that faces the first axial direction and a second surface that faces the second axial direction; and

wherein the rotor cheek sufficiently surrounds the annular member such that the rotor cheek contacts the first and second surfaces.

7. The brake rotor of claim 1 , wherein each of the first plurality of fingers and each of the second plurality of fingers is coplanar with the other fingers adjacent the wall.

8. A method of producing a brake rotor comprising:

providing a brake rotor hat having a generally circular mounting portion, a generally cylindrical wall connected to the mounting portion and being generally symmetrical about an axis, and first and second pluralities of fingers extending radially outward from the wall;

wherein each of the first plurality of fingers and each of the second plurality of fingers has a respective terminal end portion;

wherein the terminal end portions of the first plurality of fingers are coplanar about a first plane;

wherein the terminal end portions of the second plurality of fingers are not coplanar about the first plane, and are coplanar about a second plane that is parallel with the first plane;

wherein an annular member is disposed between the first and second planes; and

casting a rotor cheek around the first and second pluralities of fingers and the annular member.

9. The method of claim 8 , wherein casting the rotor cheek includes providing a mold defining a chamber having the general shape of the rotor cheek;

positioning the rotor hat so that the first and second pluralities of fingers and the annular member are disposed within the chamber; and

pouring molten casting material into the chamber.

10. The method of claim 9 , wherein the annular member is disposed within the chamber between the first and second planes such that the molten casting material contacts the annular member.

11. The method of claim 10 , wherein the first plurality of fingers limits movement of the annular member in a first axial direction, and the second plurality of fingers limits movement of the annular member in a second axial direction.

12. The method of claim 11 , wherein each of the fingers includes respective torque transmission surfaces that are positioned such that a force exerted on any one of the torque transmission surfaces urges the rotor hat to rotate about the axis; and

wherein the molten casting material contacts each of the torque transmission surfaces.