Patent Application
20130180806
1. Field of the Invention
This invention generally relates to a bicycle disc brake rotor. More specifically, the present invention relates to a bicycle disc brake rotor with a configuration that promotes cooling of the braking surfaces.
2. Background Information
In recent years, some bicycles have been provided with disc brakes. Disc brake systems provide a substantial braking power in relationship to the amount of braking force applied to the brake lever. Also, disc brake systems typically provide a high level of consistency in all types of weather and riding conditions. Disc brake systems typically include a caliper housing, a first movable brake pad and a second fixed or movable brake pad. Disc brakes can be hydraulically actuated or mechanically actuated for moving the movable brake pad(s). The brake pads are positioned on either side of a rotor, which is attached to the front or back wheel of a bicycle. The brake pads are pressed against a brake disc or rotor that is fixed to the wheel to slow down or stop the rotation of the disc, and thus, slow down or stop the rotation of the wheel.
While disc brake systems provide excellent performance, the braking action tends to generate a substantial amount of heat in the disc brake rotor. Thus, one aspect of this disclosure is to provide a disc brake rotor with a configuration that more efficiently radiates heat from the outer portion of the disc brake rotor.
In general, an iron is never used as a matrix or base material of bicycle brake disc rotor. In particular, over time, iron will usually corrode and rust due to exposure to the environment. Furthermore, iron by itself does not have sufficient strength for being used as a bicycle disc brake rotor.
Basically, in view of the state of the known technology, a bicycle disc brake rotor is basically provided that comprises a base rotor plate and a first layer. The base rotor plate includes an outer portion formed of iron. The outer portion has first and second base surfaces facing in opposite axial directions. The first layer overlies the first base surface of the outer portion of the base rotor plate to form a first outer surface. The first layer has a corrosion resistant characteristic which is superior to the base rotor plate.
These and other objects, features, aspects and advantages of the disclosed bicycle disc brake rotor will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses preferred embodiments.
Referring now to the attached drawings which form a part of this original disclosure:
Selected embodiments will now be explained with reference to the drawings. It will be apparent to those skilled in the art from this disclosure that the following descriptions of the embodiments are provided for illustration only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.
Referring initially to
The disc brake caliper 14 is constructed for selectively gripping (stopping rotation) of the bicycle disc brake rotor 12 to stop or slow the rotation of a bicycle wheel (not shown). During this braking operation, heat is generated that is transferred to the bicycle disc brake rotor 12 and the bicycle disc brake caliper 14. As explained below, the bicycle disc brake rotor 12 is designed to dissipate the heat generated during braking.
As seen in
The outer portion 22 of the base rotor plate 21 has an outer peripheral edge 22a and an inner peripheral edge 22b. The connecting arms 24 extend radially inward from the inner peripheral edge 22b of the outer portion 22. The hub mounting portion 26 is coupled to the inner ends of the connecting arms 24. As illustrated in
Referring to
Each of the first and second layers 30 and 32 has a corrosion resistant characteristic which is superior to material (iron) of the base rotor plate 21. The first and second layers 30 and 32 are preferably corrosive resistant metallic layers. More preferably, the first and second layers 30 and 32 are formed of stainless steel layers. Using stainless steel to cover the first and second base surfaces 21a and 21b will protect and strengthen the iron of the base rotor plate 21. In this way, iron can be used as the matrix or base material that forms the base rotor plate 21 of the bicycle disc brake rotor 12. The first and second layers 30 and 32 are mechanically secured or bonded to the first and second base surfaces 21a and 21b. In other words, the first and second layers 30 and 32 are not chemically bonded to the first and second base surfaces 21a and 21b (i.e., no chemical bonding occurs between the first and second layers 30 and 32 and the iron of the base rotor plate 21. In the illustrated embodiment, the first and second layers 30 and 32 are also disposed on the connecting arms 24 and the hub mounting portion 26.
The first and second layers 30 and 32 can be secured or bonded to the base rotor plate 21 in several ways. In the illustrated embodiment, for example, the first and second layers 30 and 32 can be performed plates that are attached by the third layer 34 and/or directly fastened or bonded to the first and second base surfaces 21a and 21b of the base rotor plate 21 using an adhesive, welding or brazing material (ex. Copper brazing filer metal, Copper and Alloy brazing filer metal, Nickel brazing filer metal, Aluminum brazing filer metal or Silver brazing filer metal) Alternatively, for example, the first and second layers 30 and 32 can be bonded to the first and second base surfaces 21a and 21b of the base rotor plate 21 by using a metal cladding process (metallurgically bonding) so as to form a pair of cladding layers on the base rotor plate 21. Also, for example, the first and second layers 30 and 32 can be fastened to the base rotor plate 21 using one or more fasteners such as rivets. However, preferably fasteners such as rivets are not used to fasten the first and second layers 30 and 32 to the base rotor plate 21. In any case, the first layer 30 at least overlies the first base surface 21 a along the outer portion 22 of the base rotor plate 21 to form a first outer surface. The second layer 32 at least overlies the second base surface 21b along the outer portion 22 of the base rotor plate 21 to form a second outer surface. Thus, the sections of the first and second outer surfaces 30a and 32a that overlie the outer portion 22 constitute first and second braking surfaces of the bicycle disc brake rotor 12. Thus, the sections of the first and second outer surfaces 30a and 32a that overlie the outer portion 22 are directly contacted by the brake pads of the bicycle disc brake caliper 14. As a result, in the first embodiment, the first and second layers 30 and 32 of stainless steel are secured to an iron core of the base rotor plate 21 to provide both the durability and powerful braking properties of stainless and the heat dissipation of iron.
As seen in
Depending on the configuration of the base rotor plate 21 and the configuration of the first and second layers 30 and 32, one or both of the outer and inner peripheral edges 22a and 22b of the outer portion 22 may be covered by the third layer 34. Preferably, the third layer 34 covers at least one of the outer and inner peripheral edges 22a and 22b of the outer portion 22. As seen in
Further in the illustrated embodiment, the third layer 34 covers the edges of the outer portion 22, the connecting arms 24 and the hub mounting portion 26 in the same manner as the outer portion 22. Thus, the third layer 34 covers the side peripheral edges 24a and 24b of the connecting arms 24, and the peripheral edges 26a and 26b of the hub mounting portion 26. The peripheral edge 26a of the hub mounting portion 26 defines the center opening of the hub mounting portion 26, while the peripheral edges 26b of the hub mounting portion 26 define a plurality of fastener openings. The area of the hub mounting portion 26 between the fastener openings defined by the peripheral edges 26b has a plurality of openings defined by peripheral edges 26c that are also covered by the third layer 34.
As seen in
While only selected embodiments have been chosen to illustrate the present invention, it will be apparent to those skilled in the art from this disclosure that various changes and modifications can be made herein without departing from the scope of the invention as defined in the appended claims. For example, the size, shape, location or orientation of the various components can be changed as needed and/or desired. Components that are shown directly connected or contacting each other can have intermediate structures disposed between them. The functions of one element can be performed by two, and vice versa. The structures and functions of one embodiment can be adopted in another embodiment. It is not necessary for all advantages to be present in a particular embodiment at the same time. Every feature which is unique from the prior art, alone or in combination with other features, also should be considered a separate description of further inventions by the applicant, including the structural and/or functional concepts embodied by such feature(s). Thus, the foregoing descriptions of the embodiments according to the present invention are provided for illustration only, and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.
