Apparatus for retaining a bicycle disk brake rotor to a bicycle wheel hub

A disk brake apparatus comprises a disk brake rotor, a fastener structured to screw onto a threaded surface of a bicycle wheel hub so that the disk brake rotor is disposed between the fastener and the hub, and a rotation inhibiting structure disposed on the disk brake rotor to inhibit relative rotation between the fastener and the disk brake rotor.

BACKGROUND OF THE INVENTION

The present invention is directed to bicycles and, more particularly, to an apparatus for retaining a bicycle disk brake rotor to a bicycle wheel hub.

Cycling has gained widespread acceptance not only as a means of transportation but also as a form of recreation. In fact, both amateur and professional bicycle racing has become extremely popular. As a result of these factors, the bicycle industry is constantly making improvements to various bicycle parts, whether they are used in bicycles for recreation, transportation, or racing. Bicycle braking systems in particular have undergone wide-ranging redesigns over the past few years.

Several types of bicycle braking devices are available on the market. Such devices include rim brakes, caliper brakes, disk brakes, and other general bicycle braking devices. Disk brake systems usually are the braking systems of choice when the rider requires a very high-performance braking system. That is because disk brake systems confer a very large amount of control relative to the force of operation applied to the brake lever, and they generally are very robust under any weather or riding condition.

Disk brake systems normally comprise a caliper connected to the bicycle frame, a brake lever attached to the bicycle handlebar for operating the caliper, and a disk brake rotor securely connected to the bicycle wheel hub. Several different methods are used for connecting the disk brake rotor to the wheel hub. In one method, the disc brake rotor is attached to an adapter, the adapter is attached to the hub, and then a fastener in the form of a lock ring is screwed onto the hub in order to secure the disc brake rotor assembly to the hub. Unfortunately, the lock ring can rotate relative to the hub after long years of use, vibration, etc., thereby possibly loosening the disc brake rotor assembly, even though the lock ring was tightly screwed onto the hub.

One attempt to solve the problem is disclosed in Japanese Unexamined Patent Application Publication No. 2003-136903. In that publication, serrations are formed on the face of the lock ring that contacts the disc brake rotor to help prevent loosening of the lock ring. While such a bicycle disc brake rotor assembly derives a certain anti-loosening effect due to the serrations formed on the lock ring, the contacted surface of the neighboring disc brake rotor is substantially flat, so the anti-loosening effect is inadequate.

SUMMARY OF THE INVENTION

The present invention is directed to various features of a bicycle disk brake apparatus. In one embodiment, a disk brake apparatus comprises a disk brake rotor, a fastener structured to screw onto a threaded surface of a bicycle wheel hub so that the disk brake rotor is disposed between the fastener and the hub, and a rotation inhibiting structure disposed on the disk brake rotor to inhibit relative rotation between the fastener and the disk brake rotor. Additional inventive features will become apparent from the description below, and such features alone or in combination with the above features may form the basis of further inventions as recited in the claims and their equivalents.

DETAILED DESCRIPTION OF THE EMBODIMENTS

FIG. 1is a side view of a particular embodiment of a bicycle10. Bicycle10comprises a frame14, a front wheel13rotatably connected to a front fork of frame14through a front disk brake hub12, a rear wheel13′ rotatably connected to the rear portion of frame14through a rear disk brake hub12′, a seat17adjustably connected to frame14, handlebars18connected to the front fork for rotating front wheel13, and a drive train19for propelling the bicycle10. A plurality of spokes24extend outwardly from the front and rear disk brake hubs12and12′, wherein the outer ends of spokes24are fastened to a rim25with spoke nipples (not shown) in a conventional manner. A tire26is disposed on the outer circumference of each rim25. Bicycle10and its various parts are well known, so a description thereof shall be omitted, except for the components comprising the front and rear disk brake hubs12and12′. Other components such as other brakes, derailleurs, additional sprockets, etc. may be used with bicycle10.

As shown inFIGS. 2 and 3, bicycle10further comprises front and rear disk brake assemblies20and20′, respectively. Each disk brake assembly20and21′ comprises a caliper21mounted to the front fork or frame14, respectively, a brake lever22mounted to handlebar18, and a disk brake rotor23mounted to its associated hub12or12′. Since the disk brake assemblies20and20′ are substantially the same, only the relevant components of disk brake assembly20shall be described further.

FIG. 4is an exploded view of particular embodiments of disk brake components associated with wheel hub12. In general, disk brake rotor23is detachably and nonrotatably connected to disk brake hub12using an adapter in the form of a rotor attachment boss28, and a fastener in the form of a securing ring29that screws to hub12. Disk brake rotor23, rotor attachment boss28and securing ring29comprise a disk brake rotor assembly8. Rotor attachment boss28retains disk brake rotor23to hub12without requiring rivets or bolts.

Front disk brake hub12is nearly identical to rear disk brake hub12′ except that it lacks a freewheel. As shown inFIG. 5, disk brake hub12comprises a hub axle31, a hub shell32rotatably supported on hub axle31in a conventional manner, a first spoke connecting flange33a, a second spoke connecting flange33b, and a brake rotor attachment unit34. First and second spoke connecting flanges33aand33band brake rotor attachment unit34are formed as a unified part with hub shell32.

First spoke connecting flange33ais an annular spoke flange disposed on hub shell32at a first hub shell end32aof hub shell32. A plurality of first spoke openings43aare formed circumferentially equidistant in first spoke connecting flange33afor receiving the curved ends of each of a plurality of the spokes24. Similarly, second spoke connecting flange33bis an annular spoke flange disposed on hub shell32at a second hub shell end32bof hub shell32. A plurality of second spoke openings43bare formed circumferentially equidistant in second spoke connecting flange33bfor receiving the curved ends of each of another plurality of spokes24. As a result, the spokes24extend radially outwardly in a circumferential manner.

Brake rotor attachment unit34is disposed at first hub shell end32aof hub shell32adjacent to first spoke connecting flange33a. Brake rotor attachment unit34comprises a tubular member34aand an annular adjoining flange34bextending radially outwardly from tubular member34a. Tubular member34ahas an outer peripheral surface defining a plurality of male splines34cand an inner peripheral surface defining a female threaded portion34d.

As shown inFIG. 6, rotor attachment boss28comprises an annular base member28awith a center opening28b, wherein the inner peripheral surface of center opening28bdefines a plurality of female splines28c. Splines28care structured to engage the plurality of splines34con brake rotor attachment unit34of hub12so that rotor attachment boss28can be nonrotatably attached to hub12. Rotor attachment boss28further comprises a rotor connector28dthat extends radially outwardly from base member28aand defines a plurality of equally spaced rotor attachment arms28h. Each rotor attachment arm28hpreferably includes at least one axially extending protruding portion28ethat is press fit into a corresponding opening28ffor purposes discussed below. In this embodiment, rotor attachment boss28comprises aluminum.

As shown inFIG. 7, disk brake rotor23comprises a braking ring23aformed with a plurality of openings, a plurality of (e.g., eight) connecting arms23bdisposed circumferentially equidistant and extending radially inwardly from braking ring23a, and an inner attachment unit23cconnected tangentially to the inner ends of the plurality of connecting arms23bso that the plurality of connecting arms23bform a plurality of triangular openings. In this embodiment, braking ring23a, the plurality of connecting arms23band inner attachment unit23care one piece. Disk brake rotor23preferably is made from stainless steel or some other appropriate material, usually with a specific gravity greater than that of the material forming rotor attachment boss28, that can withstand braking forces.

Inner attachment unit23cdefines a central opening23fand comprises a plurality of circumferentially equidistant connection notches23e, a plurality of circumferentially equidistant openings23g, and a plurality of circumferentially equidistant connection openings23d. Preferably, there is one connection opening23dper protruding portion28ein rotor attachment boss28. Each protruding portion28ein rotor attachment boss28engages a corresponding connection opening23din inner attachment unit23cso that disk brake rotor23may be nonrotatably attached to rotor attachment boss28. The axial length of each protruding portion28epreferably is less than or equal to the thickness of inner attachment unit23c. Inner attachment unit23calso includes a rotation inhibiting structure23hin the form of serrations, ridges, etc. that extends circumferentially around inner attachment unit23cin close proximity (e.g., directly adjacent) to central opening23f.

As shown inFIG. 8, securing ring29comprises an annular flange29cand a tubular portion29dthat extends axially from the inner peripheral surface of flange29c. Flange29cincludes a central opening29adefining a plurality of female splines29bthat are structured to engage an assembly tool (not shown). Tubular portion29dincludes a male threaded portion29estructured to engage the female threaded portion34don brake rotor attachment unit34of hub12. Thus, when securing ring29is screwed onto brake rotor attachment unit34, the side face of flange29cpresses against inner attachment unit23cof disk brake rotor23, which presses against flange34bof brake rotor attachment unit34of hub12. In this embodiment, a fastener rotation inhibiting unit29fin the form of serrations, ridges, etc. extends circumferentially around the face of flange29cso as to engage rotation inhibiting structure23hon inner attachment unit23cwhen securing ring29is screwed onto brake rotor attachment unit34.

FIG. 9is a view of disk brake rotor assembly8attached to hub12. During assembly, rotor attachment boss28initially is mounted to brake rotor attachment unit34of hub12by engaging the male splines34con brake rotor attachment unit34with the female splines28con rotor attachment boss28. Then, disk brake rotor23is placed on rotor attachment boss28by engaging protruding portions28eof rotor attachment boss28with the corresponding connection openings23din disk brake rotor23. Finally, securing ring29is screwed onto the female threaded portion34dof brake rotor attachment unit34of hub12to tightly secure disk brake rotor assembly8to hub12. The disk brake rotor23, sandwiched between rotor attachment boss28and securing ring29to form a strong connection, is thereby secured in a non-rotatable state to the brake rotor attachment unit34of hub12. The nonrotatable connection between disk brake rotor23and rotor attachment boss28prevents loosening of securing ring29during normal operation. Rotation inhibiting unit23hon disk brake rotor23further inhibits loosening of securing ring29due to long years of use, vibration, etc., and the effect is even greater when rotation inhibiting unit29fis provided on securing ring29to provide a serration-to-serration locking contact.

While the above is a description of various embodiments of inventive features, further modifications may be employed without departing from the spirit and scope of the present invention. For example,FIG. 10is an exploded view of further embodiments of disk brake components associated with wheel hub12. In this embodiment, a disk brake rotor assembly8′ comprises a disk brake rotor23′, a rotor attachment boss28′, a securing ring29and a rotor retaining member30. Rotor attachment boss28′ again includes protruding portions28ethat engage connection openings23din brake disk rotor23, and securing ring29screws into brake rotor attachment unit34of hub12as in the first embodiment. However, in this embodiment a rotation inhibiting unit23his not provided on disk brake rotor23.

Rotor retaining member30comprises an annular disk-shaped main body30c, a rotation inhibiting unit30ein the form of ridges, serrations, etc. that face flange29cof securing ring29(which may or may not have a corresponding fastener rotation inhibiting unit29fas in the first embodiment), and a plurality of (e.g., three) elastically deformable latching members30aextending perpendicularly from a lateral side face of main body30c. Each latching member30aincludes a radially inwardly curved protruding portion30bat the tip thereof. Each protruding portion30bis structured to be inserted through an insertion opening23jin disk brake rotor23and engage a step28gin a corresponding insertion opening28fof rotor attachment boss28when rotor retaining member30is attached to rotor attachment boss28′.

In this embodiment, rotor attachment boss28′ initially is mounted to brake rotor attachment unit34of hub12by engaging the female splines28con rotor attachment boss28′ with the male splines34con brake rotor attachment unit34as in the first embodiment. Then, disk brake rotor23′ is placed on rotor attachment boss28′ by engaging protruding portions28eof rotor attachment boss28with the corresponding connection openings23din disk brake rotor23. At this time, insertion openings23jin disk brake rotor23′ align with insertion openings28fin rotor attachment boss28′.

Latching members30aof rotor retaining member30then are inserted through insertion openings23jin disk brake rotor23′ and into insertion openings28fin rotor attachment boss28′. Latching members30adeflect radially outwardly until projecting portions30bmove radially inwardly to latch onto their corresponding steps28gin insertion openings28f. As a result, disk brake rotor23′ is retained to rotor attachment boss28′ simply by a single touch pressing operation on rotor retaining member30.

Finally, securing ring29is screwed onto the threaded portion34dof brake rotor attachment unit34of hub12to tightly secure disk brake rotor assembly8to hub12. The disk brake rotor23′, sandwiched between rotor attachment boss28′ and rotor retaining member30(and securing ring29) to form a strong connection, is thereby secured in a non-rotatable state to the brake rotor attachment unit34of hub12.

Once again, the nonrotatable connection between disk brake rotor23′ and rotor attachment boss28′ prevents loosening of securing ring29during normal operation. Rotation inhibiting unit30eon rotor retaining member30further inhibits loosening of fastener29due to long years of use, vibration, etc., and the effect is even greater when a rotation inhibiting unit29fis provided on securing ring29to provide a serration-to-serration locking contact.

Disk brake rotor23′ need not be sandwiched between rotor retaining member30and brake rotor attachment unit34. Instead, rotor retaining member30could be inserted from the right side through insertion openings28fin rotor attachment boss28′, through insertion openings23din disk brake rotor23′, and latch onto the side surface of disk brake rotor23′.

While the above embodiments show a separate rotor attachment boss28that nonrotatably couples disk brake rotor23to hub12,FIGS. 11 and 12show an embodiment wherein a tubular rotor attachment boss23pis formed integrally as part of a disk brake rotor23″. Rotor attachment boss23pincludes female splines23qstructured to engage the plurality of male splines34con brake rotor attachment unit34of hub12so that disk brake rotor23″ can be nonrotatably attached to hub12. Disk brake rotor23″ also includes a rotation inhibiting structure23rin the form of serrations, ridges, etc. that extends circumferentially around the radially inner portion of disk brake rotor23″ in close proximity (e.g., directly adjacent) to central a opening23sdefined by rotor attachment boss23p. Rotation inhibiting structure23rcontacts securing ring29(with or without a fastener rotation inhibiting structure29f) as in the first embodiment.

The size, shape, location or orientation of the various components may be changed as desired. Components that are shown directly connected or contacting each other may have intermediate structures disposed between them. The teachings herein could be applied to one or both of hubs12and12′. Those features that are designated as preferable certainly are not necessary. The functions of one element may be performed by two, and vice versa. The structures and functions of one embodiment may 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 scope of the invention should not be limited by the specific structures disclosed or the apparent initial focus or emphasis on a particular structure or feature.