60/541,086, filed February 2,2004.

BACKGROUND OF THE INVENTION This invention relates in general to vehicle disc brake assemblies and in particular to an improved structure for a brake rotor adapted for use in such a vehicle disc brake assembly.

Most vehicles are equipped with a brake system for slowing or stopping movement of the vehicle in a controlled manner. A typical brake system for an automobile or light truck includes a disc brake assembly for each of the front wheels and either a drum brake assembly or a disc brake assembly for each of the rear wheels. The brake assemblies are actuated by hydraulic or pneumatic pressure generated when an operator of the vehicle depresses a brake pedal. The structures of these drum brake assemblies and disc brake assemblies, as well as the actuators therefor, are well known in the art.

A typical disc brake assembly includes a rotor which is secured to the wheel of the vehicle for rotation therewith. A caliper assembly is slidably supported by pins secured to an anchor bracket. The anchor bracket is secured to a non-rotatable component of the vehicle, such as the vehicle frame. The caliper assembly includes a pair of brake shoes which are disposed on opposite sides of the rotor. The brake shoes are operatively connected to one or more hydraulically actuated pistons for movement between a non-braking position,

wherein they are spaced apart from opposed axial sides or braking surfaces of the rotor, and a braking position, wherein they are moved into frictional engagement with the opposed braking surfaces of the rotor. When the operator of the vehicle depresses the brake pedal, the piston urges the brake shoes from the non-braking position to the braking position so as to frictionally engage the opposed braking surfaces of the rotor and thereby slow or stop the rotation of the associated wheel of the vehicle.

SUMMARY OF THE INVENTION This invention relates to an improved structure for a brake rotor adapted for use in a vehicle disc brake assembly. According to one embodiment of the invention, the brake rotor includes an inner mounting flange portion and an outer annular disc portion connected thereto by a hat portion, the inner mounting flange portion having a pilot hole and a plurality of lug bolt receiving holes formed therethrough, the outer annular disc portion defining an outboard brake surface, an inboard brake surface, an outer peripheral edge surface, and an inner peripheral edge surface, the outboard brake surface and the inboard brake surface located in a generally parallel relationship relative to one another, wherein at least the outer annular disc portion is formed as an as-cast component without the use of a core piece and includes a plurality of grooves formed therein, the plurality grooves being formed therein in a pattern to produce a non-directional brake rotor.

A method for producing the one embodiment of a brake rotor adapted for use in a disc brake assembly comprises the steps of : (a) providing a casting mold which does not include a core piece; and (b) introducing a material suitable for sand casting or permanent mold casting into the mold to produce a rotor having an inner mounting flange portion and an outer annular disc portion connected thereto by a hat portion, the inner mounting flange portion having a pilot hole

and a plurality of lug bolt receiving holes formed therethrough, the outer annular disc portion defining an outboard brake surface, an inboard brake surface, an outer peripheral edge surface, and an inner peripheral edge surface, the outboard brake surface and the inboard brake surface located in a generally parallel relationship relative to one another, wherein at least the outer annular disc portion is formed as an as-cast component and includes a plurality of grooves formed therein, the plurality grooves being formed therein in a pattern to produce a non-directional brake rotor.

According to another embodiment of the invention, the brake rotor includes an inner mounting flange portion and an outer annular disc portion connected thereto by a hat portion, the inner mounting flange portion having a pilot hole and a plurality of lug bolt receiving holes formed therethrough, the outer annular disc portion defining an outboard brake surface, an inboard brake surface, an outer peripheral edge surface, and an inner peripheral edge surface, the outboard brake surface and the inboard brake surface located in a generally parallel relationship relative to one another, wherein at least the outer annular disc portion is formed as an as-cast component without the use of a core piece and includes a plurality of one of grooves formed therein which extend completely through said outer annular disc portion.

A method for producing the other embodiment of a brake rotor adapted for use in a disc brake assembly comprises the steps of : (a) providing a casting mold which does not include a core piece; and (b) introducing a material suitable for sand casting or permanent mold casting into the mold to produce a rotor having an inner mounting flange portion and an outer annular disc portion connected thereto by a hat portion, the inner mounting flange portion having a pilot hole and a plurality of lug bolt receiving holes formed therethrough, the outer annular disc portion defining an outboard brake surface, an inboard brake surface, an outer peripheral edge surface, and an inner peripheral edge surface,

the outboard brake surface and the inboard brake surface located in a generally parallel relationship relative to one another, wherein at least said outer annular disc portion is formed as an as-cast component without the use of a core piece and includes a plurality of one of grooves formed therein which extend completely through said outer annular disc portion.

Other advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiments, when read in light of the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a front perspective view of a first embodiment of a brake rotor constructed in accordance with this invention.

Fig. 2A is a front perspective view of a second embodiment of a brake rotor constructed in accordance with this invention.

Fig. 2B is a rear perspective view of the brake rotor illustrated in Fig. 2A.

Fig. 3A is a front perspective view of a third embodiment of a brake rotor constructed in accordance with this invention.

Fig. 3B is a rear perspective view of the brake rotor illustrated in Fig. 3A.

Fig. 4A is a front perspective view of a fourth embodiment of a brake rotor constructed in accordance with this invention.

Fig. 4B is a rear perspective view of the brake rotor illustrated in Fig. 4A.

Fig. 5 is a front perspective view of a fifth embodiment of a brake rotor constructed in accordance with this invention.

Fig. 6A is a front perspective view of a sixth embodiment of a brake rotor constructed in accordance with this invention.

Fig. 6B is a rear perspective view of the brake rotor illustrated in Fig. 6A.

Fig. 7A is a front perspective view of a seventh embodiment of a brake rotor constructed in accordance with this invention.

Fig. 7B is a rear perspective view of the brake rotor illustrated in Fig. 7A.

Fig. 8 is a front perspective view of an eighth embodiment of a brake rotor constructed in accordance with this invention.

Fig. 9A is a front perspective view of a ninth embodiment of a brake rotor constructed in accordance with this invention.

Fig. 9B is another front perspective view of the brake rotor illustrated in Fig. 9A.

Fig. 9C is a plan view of the brake rotor illustrated in Fig. 9A.

Fig. 9D is an enlarged view of a portion of the brake rotor illustrated in Fig. 9C.

Fig. 10 is a front perspective view of a tenth embodiment of a brake rotor constructed in accordance with this invention.

Fig. 11 is a front perspective view of an eleventh embodiment of a brake rotor constructed in accordance with this invention.

Fig. 12 is a perspective view of a portion of a prior art vehicle disc brake assembly.

Fig. 13 is an exploded perspective view of selected components of the prior art vehicle disc brake assembly illustrated in Fig. 12.

Fig. 14 is a sectional elevational view of a portion of the prior art disc brake assembly illustrated in Fig. 12.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, there is illustrated in prior art Figs. 12-14 a portion of a prior art vehicle disc brake assembly, indicated generally at 10.

The general structure and operation of the prior art disc brake assembly 10 is conventional in the art. Thus, only those portions of the prior art disc brake assembly 10 which are necessary for a full understanding of this invention will be explained and illustrated. Although this invention will be described and

illustrated in connection with the particular kind of vehicle disc brake assembly 10 disclosed herein, it will be appreciated that this invention may be used in connection with other kinds of disc brake assemblies if so desired.

As shown in prior art Fig. 12, the disc brake assembly 10 is a sliding type of disc brake assembly and includes a generally C-shaped caliper, indicated generally at 12. The caliper 12 includes an inboard leg portion 14 and an outboard leg portion 16 which are interconnected by an intermediate bridge portion 18. The caliper 12 is slidably supported on a pair of pins 20 secured to an anchor bracket, indicated generally at 22. The anchor bracket 22 is, in turn, secured to a stationary component of the vehicle. Such a stationary component can be, for example, an axle flange (not shown), when the disc brake assembly 10 is installed for use on the rear of the vehicle, or a steering knuckle (not shown), when the disc brake assembly 10 is installed for use on the front of the vehicle.

The pins 20 extend through non-threaded apertures 14A formed in the inboard leg 14 of the caliper 12. The pins 20 have respective threaded ends 20A which are received in threaded apertures 22A provided in anchor bracket 22.

The pins 20 support the caliper 12 for sliding movement relative to the anchor bracket 22 in both the outboard direction (left when viewing prior art Fig. 14) and the inboard direction (right when viewing prior art Fig. 14). Such sliding movement of the caliper 12 occurs when the disc brake assembly 10 is actuated, as will be explained below. A pair of bolts (not shown) extend through a pair of non-threaded apertures 22B formed in the anchor bracket 22 to secure the anchor bracket 22 to the stationary vehicle component. Alternatively, other known securing methods can be used to secure the anchor bracket 22 to the stationary vehicle component.

As best shown in prior art Fig. 13, the anchor bracket 22 includes a pair of axially and outwardly extending arms 24 and 26 which are interconnected at their

inboard ends by an inner tie bar 28. The arms 24 and 26 have upstanding guide rails 24A and 26A, respectively formed thereon. The guide rails 24A and 26A extend transverse to the arms 24 and 26, respectively, and parallel to one another.

The guide rails 24A and 26A slidably support an inboard brake shoe, indicated generally at 30, and an outboard brake shoe, indicated generally at 32, respectively.

The inboard brake shoe 30 includes a backing plate 34 and a friction pad 36. The inboard backing plate 34 includes opposed ends having notches 34A and 34B formed therein, for supporting the inboard brake shoe 30 on the guide rails 24A and 26A of the anchor bracket 22. The outboard brake shoe 32 includes a backing plate 38 and a friction pad 40. The outboard backing plate 38 includes opposed ends having notches 38A and 38B formed therein, for supporting the outboard brake shoe 32 on the guide rails 24A and 26A of the anchor bracket 22. Alternatively, the inboard brake shoe 30 can be supported on a brake piston of the prior art disc brake assembly 10, while the outboard brake shoe 32 can be supported on the outboard leg portion 16 of the caliper 12.

An actuation means, indicated generally at 50 in prior art Fig. 14, is provided for effecting the operation of the disc brake assembly 10. The actuation means 50 includes a brake piston 42 which is disposed in a counterbore or recess 14B formed in the outboard surface of the inboard leg 14 of the caliper 12. The actuation means 50, shown in this embodiment as being a hydraulic actuation means, is operable to move the piston 42 within the recess 14B in the outboard direction (left when viewing prior art Fig. 14). However, other types of actuation means 50, such as for example, electrical, pneumatic, and mechanical types, can be used.

The prior art disc brake assembly 10 also includes a dust boot seal 44 and an annular fluid seal 46. The dust boot seal 44 is formed from a flexible material and has a first end which engages an outboard end of the recess 14B. A second

end of the dust boot seal 44 engages an annular groove formed in an outer side wall of the piston 42. A plurality of flexible convolutions are provided in the dust boot seal 44 between the first and second ends thereof. The dust boot seal 44 is provided to prevent water, dirt, and other contaminants from entering into the recess 14B. The fluid seal 46 is disposed in an annular groove formed in a side wall of the recess 14B and engages the outer side wall of the piston 42. The fluid seal 46 is provided to define a sealed hydraulic actuator chamber 48, within which the piston 42 is disposed for sliding movement. Also, the fluid seal 46 is designed to function as a"roll back"seal to retract the piston 42 within the recess 14B (right when viewing prior art Fig. 14) when the brake pedal is released.

The prior art disc brake assembly 10 further includes a brake rotor 52, which is connected to a wheel (not shown) of the vehicle for rotation therewith.

The illustrated brake rotor 52 includes a pair of opposed friction discs 54 and 56 which are spaced apart from one another by a plurality of intermediate fins or posts 58 in a known manner to produce a"vented"or"ventilated"brake rotor.

The brake rotor 52 extends radially outwardly between the inboard friction pad 36 and the outboard friction pad 40.

When it is desired to actuate the prior art disc brake assembly 10 to retard or stop the rotation of the brake rotor 52 and the vehicle wheel associated therewith, the driver of the vehicle depresses the brake pedal (not shown). In a manner which is well known in the art, the depression of the brake pedal causes pressurized hydraulic fluid to be introduced into the chamber 48. Such pressurized hydraulic fluid urges the piston 42 in the outboard direction (toward the left when viewing prior art Fig. 14) into engagement with the backing plate 34 of the inboard brake shoe 30. As a result, the friction pad 36 of the inboard brake shoe 30 is moved into frictional engagement with the inboard friction disc 54 of the brake rotor 52. At the same time, the caliper 12 slides on the pins 20 in the inboard direction (toward the right when viewing prior art Fig. 14) such that

the outboard leg 16 thereof moves the friction pad 40 of the outboard brake shoe 32 into frictional engagement with the outboard friction disc 56 of the brake rotor 52. As a result, the opposed friction discs 54 and 56 of the brake rotor 52 are frictionally engaged by the respective friction pads 36 and 40 to slow or stop relative rotational movement thereof. The structure and operation of the prior art disc brake assembly 10 thus far described is conventional in the art.

Turning now to Fig. 1, there is illustrated a first embodiment of a brake rotor, indicated generally at 110, in accordance with this invention. The rotor 110 is preferably a"full cast"brake rotor and is formed as a one-piece casting.

The rotor 110 is preferably cast from a material which is suitable for a sand casting process or a permanent mold casting process. For example, the rotor 110 can be cast from grey cast iron. Alternatively, the rotor 110 may be formed from other materials and/or cast by other processes. For example, the rotor 110 may be formed from alternative cast iron, composites, aluminum or alloys thereof, and/or cast by a permanent mold casting process, a squeeze casting process, or a high pressure forming/casting process.

The rotor 110 includes an inner mounting flange portion 112 and an outer annular disc portion 114 connected thereto by a circumferential wall or hat portion 116. The inner mounting flange portion 112 is formed having a relatively large pilot hole 118 which is located concentrically about an axis of rotation for the rotor 110. A plurality of lug bolt receiving holes 120 (five of such lug bolt receiving holes 120 being illustrated), are also formed through the inner mounting flange portion 112 of the rotor 110. The lug bolt receiving holes 120 are equally spaced circumferentially about the pilot hole 118. A lug bolt (not shown) extends through each of the lug bolt receiving holes 120 for securing the rotor 110 to a vehicle wheel (not shown) for rotation therewith.

The outer annular disc portion 114 defines an outboard brake surface 122, an inboard brake surface 124, an outer peripheral edge surface 126, and an inner

peripheral edge surface 128. The outboard brake surface 122 and the inboard brake surface 124 are located in a generally parallel relationship relative to one another. The outer peripheral edge surface 126 defines an outer rotor diameter, and the inner peripheral edge surface 128 defines an inner rotor diameter.

The outboard brake surface 122 of the outer annular disc 114 includes a plurality of slanted or curved relatively"thin"fins 130 formed therein. In the illustrated embodiment, the outboard brake surface 122 includes a total of thirty- seven such fins 130. Each of the fins 130 extend radially inwardly from the outer peripheral edge surface 126 to about an outer surface of the hat portion 116. In the illustrated embodiment, the fins 130 are identical to each other and are evenly spaced around the circumference of the rotor 110. A recessed as-cast air passage or groove 132 is defined in the outboard brake surface 122 between each successive pair of fins 130.

Similarly, the inboard brake surface 124 of the outer annular disc 114 includes a plurality of slanted or curved relatively"thin"fins 134 formed therein.

In the illustrated embodiment, the inboard brake surface 124 includes a total of thirty-seven such fins 134 (not all the fins 134 being visible in Fig. 1). The fins 134 extend radially inwardly from the outer peripheral edge surface 126 to the inner peripheral edge surface 128. In the illustrated embodiment, the fins 134 are identical to each other and are evenly spaced around the circumference of the rotor 110. A recessed as-cast air passage or groove 136 is defined in the outboard brake surface 122 between each successive pair of fins 134.

In the illustrated embodiment, the shape, arrangement, spacing, size, quantity and direction or orientation of the fins 130 and 132 on the respective brake surfaces 122 and 124 are essentially the same. Since the fins 130 and 134 extend in the same direction, the brake rotor 110 is a"directional"brake rotor.

As used herein, the term directional brake rotor means that due to the direction or orientation of the associated fins of the brake rotor, a different brake rotor must

be used on the left and right sides of the car (commonly referred to as a"handed" brake rotor). Alternatively, the shape, arrangement, spacing, size, quantity and/or the direction or orientation of one or more of the fins 130 and 132 of the brake rotor 110 can be other than illustrated if so desired.

Turning now to Figs. 2A and 2B and using like reference numbers to indicate corresponding parts, there is illustrated a second embodiment of a rotor, indicated generally at 210, in accordance with this invention. The rotor 210 is preferably a"full cast vented"brake rotor and is formed as a one-piece casting.

The rotor 210 is preferably cast from a material which is suitable for a sand casting process or a permanent mold casting process. For example, the rotor 210 can be cast from grey cast iron. Alternatively, the rotor 210 may be formed from other materials and/or cast by other processes.

In this embodiment, an outboard brake surface 222 of the rotor 210 includes a plurality of slanted or curved relatively"wide"fins 230 formed therein. In the illustrated embodiment, the outboard brake surface 222 includes a total of eleven such fins 230. Similarly, an inboard brake surface 224 includes a plurality of slanted or curved relatively"wide"fins 234 formed therein. In the illustrated embodiment, the inboard brake surface 224 includes a total of eleven such fins 234. In this embodiment, the fins 230 and 234 are arranged on the respective brake surfaces 222 and 224 so as to extend in opposite directions and cross each other in a generally a mid-brake plate area. Since the fins 230 and 234 extend in opposite directions, the brake rotor 210 is a"non-directional" brake rotor. As used herein, the term non-directional brake rotor means that due to the direction or orientation of the associated fins of the brake rotor, the same brake rotor can be used on the left and right sides of the car (commonly referred to as a"non-handed"brake rotor). Alternatively, the shape, arrangement, spacing, size, quantity and/or the direction or orientation of one or more of the fins 230 and 234 can be other than illustrated if so desired.

Turning now to Figs. 3A and 3B and using like reference numbers to indicate corresponding parts, there is illustrated a third embodiment of a rotor, indicated generally at 310, in accordance with this invention. The rotor 310 is preferably a"full cast vented"brake rotor and is formed as a one-piece casting.

The rotor 310 is preferably cast from a material which is suitable for a sand casting process or a permanent mold casting process. For example, the rotor 310 can be cast from grey cast iron. Alternatively, the rotor 310 may be formed from other materials and/or cast by other processes.

In this embodiment, an outer annular disc portion 314 includes a plurality of elongated slanted or curved as-cast through holes or openings 330 formed therein. In the illustrated embodiment, the outer annular disc portion 314 includes a total of nineteen such openings 330. Since the openings 330 are slightly curved and extend in a generally radially outward direction, the brake rotor 310 is a directional brake rotor. Alternatively, the shape, arrangement, spacing, size, quantity and/or the direction or orientation of one or more of the openings 330 can be other than illustrated if so desired.

Turning now to Figs. 4A and 4B and using like reference numbers to indicate corresponding parts, there is illustrated a fourth embodiment of a rotor, indicated generally at 410, in accordance with this invention. The rotor 410 is preferably a"full cast vented"brake rotor and is formed as a one-piece casting.

The rotor 410 is preferably cast from a material which is suitable for a sand casting process or a permanent mold casting process. For example, the rotor 410 can be cast from grey cast iron. Alternatively, the rotor 410 may be formed from other materials and/or cast by other processes.

In this embodiment, an outboard brake surface 422 includes a plurality of slanted or curved relatively"wide"fins 430 formed therein. In the illustrated embodiment, the outboard brake surface 422 includes a total of thirteen such fins 430. Similarly, an inboard brake surface 424 includes a plurality of slanted or

curved relatively"wide"fins 434 formed therein. In the illustrated embodiment, the inboard brake surface 424 includes a total of thirteen such fins 434. In this embodiment, the fins 430 and 434 are arranged on the respective brake surfaces 422 and 424 so as to extend in the same direction. The illustrated brake rotor 410 further includes an as-cast through opening 450 formed therein between each successive pair of fins 430 and 434. In this embodiment, since the fins 430 and 432 extend in the same direction, the brake rotor 410 is a directional brake rotor.

Further, the illustrated brake rotor 410 includes a plurality of"lower"or "inner"supporting ribs 452 and a plurality of"upper"or"outer"supporting ribs 454. Preferably, the ribs 452 and 454 are offset inwardly relative to the brake surfaces 422 and 424 so as not to form any part of the associated brake surfaces 422 and 424. Since the brake surfaces 422 and 424 of the outer annular disc portion 414 of the brake rotor 410 are supported at their associated outer peripheral edge surface 426 and inner peripheral edge surface 428 by the outer ribs 454 and the inner ribs 452, respectively, the outer annular disc portion 414 is "double supported". As used herein, the term double-supported means that due to the connection provided by the inner ribs 452 and outer ribs 454 of the brake rotor 410, the outer annular disc portion 414 of the brake rotor 410 is supported at two places between its inner diameter and outer diameter. In this embodiment, the ribs 452 and 454 support the outer annular disc portion 414 continuously at its inner diameter and outer diameter. Alternatively, the shape, arrangement, spacing, size, quantity and/or the direction or orientation of one or more of the fins 430 and 432 and/or the ribs 452 and 454 can be other than illustrated if so desired.

Turning now to Fig. 5 and using like reference numbers to indicate corresponding parts, there is illustrated a fifth embodiment of a rotor, indicated generally at 510, in accordance with this invention. The rotor 510 is preferably a

"full cast vented"brake rotor and is formed as a one-piece casting. The rotor 510 is preferably cast from a material which is suitable for a sand casting process or a permanent mold casting process. For example, the rotor 510 can be cast from grey cast iron. Alternatively, the rotor 510 may be formed from other materials and/or cast by other processes.

In this embodiment, an outer annular disc portion 514 includes a plurality of as-cast holes or openings 550 formed therein. In particular, the openings 550 have a generally circular shape except that the openings 550A and 550B at an outer peripheral edge surface 526 and an inner peripheral edge surface 528, respectively, are generally half holes and thus, have a semi-circular shape.

Turning now to Figs. 6A and 6B and using like reference numbers to indicate corresponding parts, there is illustrated a sixth embodiment of a rotor, indicated generally at 610, in accordance with this invention. The rotor 610 is preferably a"full cast vented"brake rotor and is formed as a one-piece casting.

The rotor 610 is preferably cast from a material which is suitable for a sand casting process or a permanent mold casting process. For example, the rotor 610 can be cast from grey cast iron. Alternatively, the rotor 610 may be formed from other materials and/or cast by other processes.

In this embodiment, an outboard brake surface 622 includes a plurality of slanted or curved relatively"wide"fins 630 formed therein. In the illustrated embodiment, the outboard brake surface 622 includes a total of thirteen such fins 630. Similarly, an inboard brake surface 624 includes a plurality of slanted or curved relatively"wide"fins 634 formed therein. In the illustrated embodiment, the inboard brake surface 624 includes a total of thirteen such fins 634. In this' embodiment, the fins 630 and 634 are arranged on the respective brake surfaces 622 and 624 so as to extend in the same direction. The illustrated brake rotor 510 further includes an as-cast through opening or groove 650 formed therein between each successive pair of fins 630 and 634. In this embodiment, since the

fins 630 and 632 extend in the same direction, the brake rotor 610 is a directional brake rotor.

Further, an outer annular disc portion 614 of the brake rotor 610 includes a plurality of"lower"or"inner"supporting ribs 652. Preferably, the ribs 652 are offset inwardly relative to the brake surfaces 622 and 624 so as not to form any part of the associated brake surfaces 622 and 624. The ribs 652 extend radially outwardly from an inner peripheral edge surface 628 toward an outer peripheral edge surface 626 of the brake rotor 610. In the illustrated embodiment, the ribs 652 extend radially outwardly approximately one-half a total radial distance defined by the brake surfaces 622 and 624. Since the ribs 652 are"partial"ribs, in that they do not extend all the way out to the outer peripheral edge surface 626, the outer annular disc portion 614 is"single supported". As used herein, the term single supported means that due to the connection provided by the ribs 652 of the brake rotor 610, the outer annular disc portion 614 of the brake rotor 610 is supported at one point between its inner diameter and outer diameter.

Alternatively, the shape, arrangement, spacing, size, quantity and/or the direction or orientation of one or more of the fins 630 and 634 and/or the ribs 652 can be other than illustrated if so desired.

Turning now to Figs. 7A and 7B and using like reference numbers to indicate corresponding parts, there is illustrated a seventh embodiment of a rotor, indicated generally at 710, in accordance with this invention. The rotor 710 is preferably a"full cast vented"brake rotor and is formed as a one-piece casting.

The rotor 710 is preferably cast from a material which is suitable for a sand casting process or a permanent mold casting process. For example, the rotor 710 can be cast from grey cast iron. Alternatively, the rotor 710 may be formed from other materials and/or cast by other processes.

In this embodiment, an outboard brake surface 722 includes a plurality of uniquely shaped fins formed therein. In particular, the outboard brake surface

722 includes a plurality of first fins 730A and a plurality of second fins 730B.

The first fins 730A and the second fins 730B are arranged in an alternating manner about the circumference of the outboard brake surface 722. In the illustrated embodiment, the outboard brake surface 722 includes seven first fins 730A and seven such second fins 730B. The first fins 730A are tapered radially outwardly such that they are wider or thicker at their outer ends as compared to their inner ends. The second fins 730B are tapered radially inwardly such that they are wider or thicker at their inner ends as compared to their outer ends.

Similarly, an inboard brake surface 724 includes a plurality of uniquely shaped fins formed therein. In particular, the inboard brake surface 724 includes a plurality of first fins 734A and a plurality of second fins 734B. The first fins 734A and the second fins 734B are arranged in an alternating manner about the circumference of the inboard brake surface 724. In the illustrated embodiment, the outboard brake surface 724 includes seven first fins 734A and seven such second fins 734B. The first fins 734A are tapered radially outwardly such that they are wider or thicker at their outer ends as compared to their inner ends. The second fins 734B are tapered radially inwardly such that they are wider or thicker at their inner ends as compared to their outer ends. In this embodiment, the fins 730A and 730B and the fins 734A and 734B are arranged on the respective brake surfaces 722 and 724 so as to extend in the same direction. The illustrated brake rotor 710 further includes an as-cast through opening or groove 750 formed therein between each successive pair of fins 730A and 730B and 734A and 734B. In this embodiment, since the fins 730A and 730B and 734A and 734B extend in alternating directions on each of the respective brake surfaces 722 and 724, the brake rotor 710 is a non-directional brake rotor.

Further, the brake rotor 710 includes a plurality of"lower"or"inner" supporting ribs 752 and a plurality of"upper"or"outer"supporting ribs 754.

Preferably, the ribs 752 and 754 are offset inwardly relative to the brake surfaces

722 and 724 so as not to form any part of the associated brake surfaces 722 and 724. Also, since the brake surfaces 722 and 724 of the outer annular disc portion 714 of the brake rotor 710 are supported at their associated outer peripheral edge surface 726 and inner peripheral edge surface 728 by the outer ribs 754 and the inner ribs 752, respectively, the outer annular disc portion 714 of the brake rotor 710 is double supported. Alternatively, the shape, arrangement, spacing, size, quantity and/or the direction or orientation of one or more of the fins 730A and 730B and 734A and 734B can be other than illustrated if so desired.

Turning now to Fig. 8 and using like reference numbers to indicate corresponding parts, there is illustrated an eighth embodiment of a rotor, indicated generally at 810, in accordance with this invention. The rotor 810 is preferably a"full cast vented"brake rotor and is formed as a one-piece casting.

The rotor 810 is preferably cast from a material which is suitable for a sand casting process or a permanent mold casting process. For example, the rotor 810 can be cast from grey cast iron. Alternatively, the rotor 810 may be formed from other materials and/or cast by other processes.

In this embodiment, an outer annular disc portion 814 includes a plurality of elongated as-cast slanted or curved through openings or grooves 830 formed therein. In the illustrated embodiment, the outer annular disc portion 814 includes a total of forty such openings 830. Since the openings 830 extend in a generally circumferential direction, the brake rotor 810 is a non-directional brake rotor. Alternatively, the shape, arrangement, spacing, size, quantity and/or the direction or orientation of one or more of the openings 830 can be other than illustrated if so desired.

Turning now to Figs. 9A through 9D and using like reference numbers to indicate corresponding parts, there is illustrated a ninth embodiment of a rotor, indicated generally at 910, in accordance with this invention. The rotor 910 is preferably a"full cast vented"brake rotor and is formed as a one-piece casting.

The rotor 910 is preferably cast from a material which is suitable for a sand casting process or a permanent mold casting process. For example, the rotor 910 can be cast from grey cast iron. Alternatively, the rotor 910 may be formed from other materials and/or cast by other processes.

In this embodiment, an outboard brake surface 922 includes a plurality of uniquely shaped fins formed therein. In particular, the outboard brake surface 922 includes a plurality of first fins 93 OA and a plurality of second fins 93 OB.

The first fins 930A and the second fins 930B are arranged in an alternating manner about the circumference of the outboard brake surface 922. In the illustrated embodiment, the outboard brake surface 922 includes seven first fins 930A and seven such second fins 930B. The first fins 930A and the second fins 930B are arranged in an alternating manner about the circumference of the outboard brake surface 922. In the illustrated embodiment, the outboard brake surface 922 includes seven first fins 930A and seven such second fins 930B.

The first fins 930A are tapered radially outwardly such that they are wider or thicker at their outer ends as compared to their inner ends. The second fins 930B are tapered radially inwardly such that they are wider or thicker at their inner ends as compared to their outer ends.

Similarly, an inboard brake surface 924 includes a plurality of uniquely shaped fins formed therein. In particular, the inboard brake surface 924 includes a plurality of first fins 934A and a plurality of second fins 934B. The first fins 934A and the second fins 934B are arranged in an alternating manner about the circumference of the inboard brake surface 924. In the illustrated embodiment, the outboard brake surface 924 includes seven first fins 934A and seven such second fins 934B. The first fins 934A are tapered radially outwardly such that they are wider or thicker at their outer ends as compared to their inner ends. The second fins 934B are tapered radially inwardly such that they are wider or thicker at their inner ends as compared to their outer ends. In this embodiment, the fins

930A and 930B and the fins 934A and 934B are arranged on the respective brake surfaces 922 and 924 so as to extend in the same direction. Since the fins 930A and 930B and 934A and 934B extend in alternating directions, the brake rotor 910 is a non-directional brake rotor. Alternatively, the shape, arrangement, spacing, size, quantity and/or the direction or orientation of one or more of the fins 930A and 930B and 934A and 934B can be other than illustrated if so desired.

Further, the brake rotor 910 further includes an as-cast through opening or groove 950 formed therein between each successive pair of associated fins 930A/934A and 930B/934B. In the illustrated embodiment, the opening 950 preferably includes an as-cast chamfered side wall 950A formed in the outboard brake surface 922 (best shown in Fig. 9D), and a cast chamfered side wall 950B formed in the inboard brake surface 924. The side walls 950A and 950B extend into the respective brake surfaces 922 and 924 a predetermined depth or distance D and are oriented at a predetermined angle A with respect to the brake surfaces 922 and 924. The depth D is preferably not greater than approximately about 30 percent of the total thickness of the outer annular disc portion 914 and the angle A is preferably approximately forty-five degrees. More preferably, the depth D is approximately in the range of about 4 to about 10 percent of the total thickness of the outer annular disc portion 914. Alternatively, the depth D and/or the angle A can be other than described if so desired. Also, one or more of the openings 950 can be straight openings without any chamfered side wall if so desired.

The brake rotor 910 further includes a plurality of"lower"or"inner" supporting ribs 952 and a plurality of"upper"or"outer"supporting ribs 954. In the illustrated embodiment, the ribs 952 and 954 are offset inwardly relative to the brake surfaces 922 and 924 so as not to form any part of the associated brake surfaces 922 and 924. In this embodiment, the outer ribs 954 are spaced inwardly from the outer diameter of the brake surfaces 922 and 924. Also, since

the brake surfaces 922 and 924 of the outer annular disc portion 914 of the brake rotor 910 are supported at their associated inner peripheral edge surface 928 by the inner ribs 952 and near their associated outer peripheral edge surface 926 by the outer ribs 954, the outer annular disc portion 914 is double supported.

Alternatively, the shape, arrangement, spacing, size, quantity and/or the direction or orientation of one or more of the ribs 952 and 954 and/or the openings 950 can be other than illustrated if so desired. For example, the ribs 954 could extend to the outer peripheral edge surface 926.

In this embodiment, the brake rotor 910 also includes a plurality of optional notches or recesses 940. Preferably, a notch 940 is provided in each of the brake surfaces 922 and 924 at the outer peripheral edge surface 926 thereof.

In the illustrated embodiment, each notch 940 has a generally semi-circular shape and a notch 940 is provided generally intermediate each of the fins 930A and 930B and 934A and 934B of the inboard brake surface 922 and the outboard brake surface 924, respectively. Alternatively, the shape, arrangement, spacing, size, quantity and/or the direction or orientation of one or more of the notches 940 can be other than illustrated if so desired.

Turning now to Fig. 10, and using like reference numbers to indicate corresponding parts, there is illustrated a tenth embodiment of a rotor, indicated generally at 1010, in accordance with this invention. The rotor 1010 is preferably a"full cast vented"brake rotor and is formed as a one-piece casting.

The rotor 1010 is preferably cast from a material which is suitable for a sand casting process or a permanent mold casting process. For example, the rotor 1010 can be cast from grey cast iron. Alternatively, the rotor 1010 may be formed from other materials and/or cast by other processes.

In this embodiment, an outboard brake surface 1022 includes a plurality of uniquely shaped fins formed therein. In particular, the outboard brake surface 1022 includes a plurality of first"outer"fins 103 osa, a plurality of second

"intermediate"fins 1030B, and a plurality of third"inner"fins 1030C. The first fins 1030A, the second fins 1030B and the third fins 1030C are arranged in the pattern shown on the outboard brake surface 1022 due to the shape of as-cast grooves 1040 formed therein. The grooves 1040 are in the form of a generally lobe-like configuration and are formed by a series of multiple intertwined loops.

In the illustrated embodiment, the outboard brake surface 1022 includes five first fins 1040A, five second fins 1040B and five such third fins 1040C. Preferably, an inboard brake surface 1024 of the brake rotor 1010 has a similar construction to that of the outboard brake surface 1020 to produce a non-directional brake rotor. Alternatively, the shape, arrangement, spacing, size, quantity and/or the direction or orientation of one or more of the fins 1030A, 1030B and 1030C and/or the groove 1040 can be other than illustrated if so desired.

Turning now to Fig. 11, and using like reference numbers to indicate corresponding parts, there is illustrated an eleventh embodiment of a rotor, indicated generally at 1110, in accordance with this invention. The rotor 1110 is preferably a"full cast vented"brake rotor and is formed as a one-piece casting.

The rotor 1110 is preferably cast from a material which is suitable for a sand casting process or a permanent mold casting process. For example, the rotor 1110 can be cast from grey cast iron. Alternatively, the rotor 1110 may be formed from other materials and/or cast by other processes.

In this embodiment, an outboard brake surface 1122 includes a plurality of uniquely shaped fins formed therein. In particular, the outboard brake surface 1122 includes a plurality of first"outer"fins 1130A, a plurality of second "intermediate"fins 1130B, and a plurality of third"inner"fins 1130C. The first fins 1130A, the second fins 1130B and the third fins 1130C are arranged in the pattern shown on the outboard brake surface 1122 due to the shape of as-cast grooves 1140 formed therein. The grooves 1140 are in the form of a generally lobe-like configuration and are formed by a series of continuous intertwined

loops. In the illustrated embodiment, the outboard brake surface 1122 includes nine first fins 1040A, nine second fins 1040B and nine such third fins 1040C.

Preferably, an inboard brake surface 1124 of the brake rotor 1110 has a similar construction to that of the outboard brake surface 1120 to produce a non- directional brake rotor. Alternatively, the shape, arrangement, spacing, size, quantity and/or the direction or orientation of one or more of the fins 1130A, 113 OB and 1130C can be other than illustrated if so desired.

One advantage of the brake rotors 110,210, 310,410, 510,610, 710,810, 910, 1010 and 1110 of this invention is that they can be produced without a core piece. Other advantages and/or features of this invention is that the brake rotors 110,210, 310, 410, 510, 610,710, 810, 910, 1010 and 1110 can possibly improve packaging, improve cooling, improve or reduce coning, reduce mechanical stresses, reduce the weight of the brake rotor, and/or benefit the design of surrounding components of the brake assembly, such as the caliper and the brake shoe assemblies, compared to conventional vented brake rotors produced with a core piece.

While the brake rotors 110, 210,310, 410,510, 610,710, 810,910, 1010 and 1110 of this invention have been illustrated and described as being a full cast rotor, the invention may be used in connection with other types of brake rotors.

For example, the invention may be used in connection with a"uni-cast"brake rotor, wherein the brake rotor includes an integral hub portion, such as shown in U. S. Patent No. 5, 430, 926 to Hartford, the disclosure of which is incorporated in entirety herein by reference ; or in connection with a"composite"brake rotor, such as shown in U. S. Patent No. 5,509, 510 to Ihm or U. S. Patent No. 4,930, 606 to Sporzynski et al. , the disclosures of which are incorporated in entirety herein by reference. Also, the brake rotors 110,210, 310, 410,510, 610,710, 810, 910, 1010 and 1110 of this invention can be used in connection with various kinds of disc brake assemblies. For example, the brake rotors 110,210, 310,410, 510,

610,710, 810, 910, 1010 and 1110 can be used in connection with the disc brake assemblies shown in U. S. Patent No. 6,386, 335 to DiPonio, U. S. Patent No.

6,378, 665 to McCormick et al. , U. S. Patent No. 5,921, 354 to Evans, U. S. Patent<BR> No. 5,535, 856 to McCormick et al. , U. S. Patent No. 5,549, 181 to Evans, U. S.<BR> <P>Patent No. 5,542, 503 to Dunn et al. , U. S. Patent No. 5,322, 145 to Evans or U. S.

Patent No. 5,180, 037 to Evans, the disclosures of each of these patents incorporated in entirety herein by reference.

In accordance with the provisions of the patent statutes, the principle and mode of operation of this invention have been described and illustrated in its preferred embodiments. However, it must be understood that this invention may be practiced otherwise than as specifically explained and illustrated without departing from its spirit or scope.