The present invention relates generally to a brake rotor assembly for an automotive vehicle.
An important issue with current brake rotor/hub designs involves distortion of the braking surface due to bolt-up variations during wheel assembly. This distortion, which is quantified by lateral run-out (LRO), is caused by many factors including machining and assembly tolerances, presence of dirt or other foreign matter between mating surfaces, or due to the introduction of non-uniform or uneven clamping forces.
Lateral run-out of the braking surface causes significantly increased wear of the brake rotors and friction material, therefore, there exists a need for a brake rotor assembly wherein the brake rotor is attached to the hub portion in such a way that “on-vehicle”, or wheel induced, lateral run-out of the brake rotor is reduced, thereby increasing the efficiency and life of the brake rotor assembly.
The present invention provides a two-piece brake rotor assembly that includes a hub portion and a brake rotor portion. The brake rotor portion is mounted onto the hub portion. In an aspect of the present application, one of the brake rotor portion and the hub portion includes extending features and the other one of the brake rotor portion and the hub portion includes receiving features. The extending features engage the receiving features to secure the brake rotor portion onto the hub portion. The engagement of the extending features and the receiving features is adapted to allow rotational movement of the rotor portion relative to the hub portion about a tangential axis at the interface between the extending portions and receiving portions.
In another aspect of the present application, the extending features include a continuous annular ridge and the receiving features include a continuous annular channel. The continuous annular ridge may include indents spaced circumferentially thereon to mechanically interlock the brake rotor portion and the hub portion to prevent circumferential movement of the brake rotor portion relative to the hub portion. Alternatively, the extending features may include a plurality of spokes and the receiving features may include a plurality of pockets formed therein such that distal ends of one of the spokes is received within each of the pockets.
In yet another aspect of the present application, the extending features include a convex, arcuate shaped distal end and the receiving features include a concave arcuate shaped pocket, the extending features extend into the receiving features such that only the arcuate shaped portion of the extending portions extends within the arcuate shaped pocket, thereby allowing rotational movement of the extending features relative to the receiving features and therefore, allowing rotational movement of the hub portion relative to the brake rotor portion.
In still another aspect of the present application, the extending features and the receiving features define a ball stud engagement, wherein the extending features have a ball formed at a distal end thereof and the receiving features define a corresponding pocket to receive the ball formed at the distal end of the extending features and allow rotational movement of the brake rotor portion relative to the hub portion. The pocket of the receiving feature may includes a flared opening to provide clearance to allow the extending portion to rotate relative to the pocket.
In yet another aspect of the present application, there is radial translation permitted between the extending features and the receiving features to allow limited radial movement of the brake rotor portion relative to the hub portion, thereby providing both limited radial movement and rotational movement of the brake rotor portion relative to the hub portion.
The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present invention, and together with the description serve to explain the principles of the invention. In the drawings:
a is a view similar to
Referring to
To prevent distortion of the brake rotor portion 14 due to bolt-up variations during assembly, the brake rotor portion 14 and the hub portion 12 are attached to one another such that rotational movement of the brake rotor portion 14 relative to the hub portion 12 is allowed in the cross-sectional plane about a tangential axis 20 as shown in
One of the brake rotor portion 14 and the hub portion 12 includes extending features 16. The other one of the brake rotor portion 14 and the hub portion 12 includes receiving features 18. The extending features 16 engage the receiving features 18 to secure the brake rotor portion 14 onto the hub portion 12. The engagement of the extending features 16 and the receiving features 18 is adapted to allow rotational movement of the brake rotor portion 14 relative to the hub portion 12 about a tangential axis 20 at the interface between the extending portions 16 and receiving portions 18.
Referring to
Alternatively, the extending features 16 can include a plurality of spokes 32 extending radially inward from the inner diameter 28 of the brake rotor portion 14 and the receiving features 18 comprise a plurality of pockets 34 formed within the outer diameter 24 of the hub portion 12, as shown in
In another embodiment, the extending features 16 comprise an annular ridge 36 extending radially outward from the outer diameter 24 of the hub portion 12 and having a plurality of circumferentially spaced radial discontinuities 37a. The receiving features 18 include an annular channel 38 formed within the inner diameter 28 of the brake rotor portion 14, as shown in
The annular ridge 36 may also include axial indents 39 formed therein and spaced circumferentially thereabout to keep the brake rotor portion 14 circumferentially locked to the hub portion 12, as shown in
Referring to
Referring to
In an alternate embodiment, the pocket 46 of the receiving feature 18a includes a flared opening 48 to provide clearance to allow the extending portion 16a to rotate relative to the pocket 46, as indicated by arrows 50 in
In still another variation of the ball stud engagement, the extending portion 16a is free to move radially with respect to the receiving portion 18a. There is no radial constraint between the ball 44 at the distal end of the extending portion 16a and the receiving portion 18a, as shown in
The foregoing description of the embodiments described herein has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Numerous modifications or variations are possible in light of the above teachings. The embodiments discussed were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled.