Background of the Invention

The present invention relates to bicycles of the type having handlebars which are adapted to be used with detachable bar ends, and is directed more particularly to an improved bar end which combines a size and shape that affords improved gripping comfort and reduced hand fatigue with a structure that affords high structural integrity and reduced overall weight.

Prior to the present invention many types and styles of handlebars have been developed for use with bicycles, such as off-road and mountain bicycles, in which the shape, strength and the weight of each component part plays a significant role in the overall performance thereof. In many cases these handlebars provide two or more hand positions or gripping locations, each of which is associated with a particular riding posture, and each of which is oriented to optimize performance for that posture. The grip location and orientation that is best suited to the nearly prone posture that is used when the bicycle is ridden under racing conditions is, for example, very different from the grip location and orientation that is best suited to the nearly erect posture that is used when the bicycle is ridden under hill-climbing conditions.

Included among these multi-grip handlebars are handlebars which are of single piece construction and include a grip segment that is roughly vertical. Examples of. handlebars of this type are shown or described in U.S. utility patent nos. 5,146,809 (Ruana), and 5,205,185 (Herman). Examples of handlebars which

are of multi-piece construction and include roughly vertical grip segments are shown or described in U.S. design patent nos. 301,027 (Borromeo) and 346,145 (Jeshurun et al) and U.S. utility patent nos. 5,138,893 (Copeland), 5,201,243 (Schneider) and 5,285,696 (Taylor). Among the latter, only the Taylor patent discloses a fully detachable bar end of the type contemplated by the present invention.

In order to make the use of handlebars more comfortable, a number of different cushioned and/or shaped grips have been developed for placement over predetermined parts of the handlebar. Examples of grips which use pads or cushions to increase rider hand comfort are described in U.S. utility patent no. 5,205,185 (Herman) and in U.S. design patent no. 332,563 (Lurkis). Examples of grips which have shapes that are intended to increase rider hand comfort include U.S. design patent nos. 100,223 (Morgan), 144,446 (Black), 269,849 (Morgan) and 269,941 (Morgan). An example of a grip which uses a plurality of small shaped pads to increase rider hand comfort is described in U.S. utility patent no. 5,146,809 (Ruana).

While each of the above-mentioned handlebars and grips have advantages, they also have certain disadvantages. Some, for example, provide a handlebar which is structurally strong, but which is either comparatively heavy or has an uncomfortable "feel." Others have a comfortable feel when first used, but lead to the development of hand and/or arm fatigue when used over an extended period. Still other grips are light and have a comfortable feel, but lack the structural

integrity to be attached to the end of a handlebar, i.e., are not strong enough to be used without a handlebar segment that is disposed in reinforcing relationship thereto.

Summary of the Invention

In accordance with the present invention there is provided an improved bar end which has a high structural integrity, which is comparatively light in weight, and which has a shape and size that affords both a comfortable feel and an improved ability to prevent the development of hand and/or arm fatigue.

Generally speaking, the bar end of the invention includes a grip having a relatively thin, unreinforced, single piece, load-bearing or monocoque shell which has a rigidity and structural integrity that allows it to apply steering forces to a handlebar without requiring that the handlebar be disposed in reinforcing relationship thereto. Because of this monocoque construction, the grip has a weight which is significantly less than previously used grips of similar strength.

In accordance with an important feature of the present invention, the shape of the grip portion of bar end is such that it provides a comfortable feel in spite of its relative hardness. This comfortable feel results from a surface configuration that provides an ergonomically comfortable position for each of the digits of the human hand, including the thumb, and not from the presence of a pad or layer of cushioning material. Because of the absence of such a cushioning

layer, the grip of the invention has a weight which is less than that of previously known grips that provide a comfortable feel.

In accordance with another feature of the present invention, the grip portion of the bar end is composed of a material which is light in weight in relation to its strength. This, in turn, allows the grip to have both a relatively large size and a relatively small weight. In accordance with the invention, the relatively large size of the grip allows it to be held with the hand in a relatively open, i.e., less tightly clenched, position. Because of this more open grip, less muscular energy is required to maintain a firm grip on the handlebar and, consequently, the bicycle may be ridden for longer periods without experiencing hand and/or arm fatigue.

The grip portion of the bar end of the present invention is able to provide the above-described benefits, in spite of its thinness and light weight, because it is used in combination with a fastening assembly and a metallic insert which allow it to apply steering forces to the handlebar without being exposed to the high fastening forces that must exist between the handlebar and the bar end. In the preferred embodiment a first, outer end of this insert is attached to both of two oppositely disposed portions of the shell and serves as a bridging member to maintain a fixed separation therebetween. At the same time, the second, inner end of this insert is shaped to cooperate with a fastening mechanism for establishing a tight, mechanically strong juncture with the end of the handlebar. Thus, the insert serves as a mechanical buffer which allows only relatively

distributed forces to be applied between itself and the grip, while allowing relatively concentrated forces to act between itself and the handlebar.

Description of the Drawings

Other objects and advantages of the bar end of the invention will be apparent from the following drawings in which:

Fig. 1 is an oblique view of a handlebar which is equipped with a pair of bar ends constructed in accordance with one embodiment of the present invention;

Fig. 2A is an enlarged, oblique, outboard view of the left hand bar end of Fig. 1;

Fig. 2B is an oblique, enlarged, inboard view of the right hand bar end of

Fig. 1;

Fig. .3A is an enlarged, fragmentary, partially cutaway, exploded view of the right hand bar end shown in Fig. 2B;

Fig. 3B is an enlarged, fragmentary side view of the right hand bar end shown in Fig. 2B;

Fig. 4A is an enlarged, fragmentary partially cutaway view of an alternative embodiment of the right hand bar end of the invention; and

Fig. 4B is an enlarged, fragmentary side view of the right hand bar end shown in Fig. 4A.

Description of the Preferred Embodiments

Referring to Fig. 1 there is shown a generally forward and downward looking oblique view of a bicycle handlebar assembly H that is constructed in accordance with one embodiment of the present invention. Handlebar assembly H includes right and left handlebar segments 10R and 10L, respectively, the proximal or inner ends of which are secured to head tube 12 of the bicycle by a handlebar stem 14. Handlebar assembly H also includes a pair of right and left hand levers 16R and 16L, respectively, which serve to actuate the braking and gear shifting assemblies of the bicycle (not shown). Together, these elements function in a conventional manner to control the orientation of the front wheel of the bicycle with respect to its steering axis S and thereby the direction in which the bicycle travels.

To the end that the bicycle may be steered comfortably and with a minimum of fatigue, handlebar H of Fig. 1 is provided with a right hand bar end 20R and a left hand bar end 20L which have been constructed in accordance one embodiment of the present invention. As shown in Fig. 1, these bar ends are located at respective distal ends of handlebar H, and are attached thereto by respective right and left hand fastening mechanisms 30R and 30L. The latter fastening mechanisms preferably have the ability to fasten the bar ends to the respective ends of handlebar H with any desired angular orientation with respect to the longitudinal axis thereof. The ability to assume different angular orientations is desirable because it allows the handlebar assembly to accommodate

riders who have different arm lengths and different preferred riding postures. The structure and operation of two types of fastening mechanism which are suitable for use with the bar ends of the invention will be described later in connection with. Figs 3A-3B and 4A-4B.

Referring to Figs. 2A and 2B there are shown enlarged oblique views of right and left hand bar ends 20R and 20L of Fig. 1. These bar ends are identical in shape, except that they comprise three dimensional mirror images of one another. Stated differently, for each point on the inner surface of each bar end (i.e., the surface which faces toward handlebar H) there will be a corresponding point on the inner surface of the other bar end. Similarly for each point on the outer surface of each bar end (i.e., the surface which faces away from handlebar H) there will be a corresponding point on the outer surface of the other bar end. The part of the surface of bar end 20R which is not shown in Fig. 2B (the outer surface) will, for example, have a shape which is the same as the part of the surface of bar end 20L which is shown in Fig. 2A (the outer surface), and vice- versa. In order to avoid unnecessary confusion and repetition, the following description will, except where noted, be directed only to right hand bar end 20R and such description will be understood to be equally applicable to left hand bar end 20L, taking into account the mirror image relationship between the latter and the former.

As shown in Fig. 2B bar end 20R includes a right hand grip member or grip 22R having an elongated distal portion 24R that is adapted to be gripped by a

right hand, and a proximal portion 26R that is adapted to be attached to the right end of handlebar H. In order to provide for a firm and comfortable grip, distal portion 24R of Grip 22R has a shape which defines a pluraUty of digit receiving channels or indentations having sizes, positions, and orientations which are based on the size and shape of a typical human hand. Included among these are a plurality of finger-receiving channels 27R, each having a central axis that is oriented roughly perpendicular to the longitudinal axis of grip 22R. Also included among these is a thumb receiving channel 28R having a central axis that is oriented in a direction that is between a direction perpendicular to the longitudinal axis of grip 22R and a direction that is parallel to that axis.

In addition, in the preferred embodiment, the inner surface of grip 22R defines a shallow recessed surface or step 29R1 that serves as a rest surface for the tips of all of the fingers, and the outer surface of grip 22R defines a shallow, convexly curved support surface 29R2 that serves to provide support to the "cup" formed by the palm of the hand when the hand is used to form a grip. Together, the digit receiving channels, inner rest surface and outer palm support surface give grip 22R a "feel" which is comfortable even in the absence of a soft covering. In this way grip 22R provides rider comfort without paying the weight penalty associated with the presence of such a soft covering. Depending on the personal preferences of the rider, rider comfort may be further enhanced by providing the exterior surface of grip 22R with either a smooth surface or a textured (i.e., rough) surface by using a mold which has the desired surface properties.

In accordance with an important feature of the present invention, grip 22R has a thin walled preferably single piece molded construction having a strength which is relatively high in relation to its weight. Grip 22R is preferably constructed from commercially available composite materials, such as planar assemblages of graphite or fiberglass fibers which have been pre-impregnated with conventional curable resins ("prepregs"). Grip 22R may, for example, be constructed by an inflatable bladder process by placing cut pieces of prepreg tape or fabric in the desired pattern in a mold, and/or on an inflatable bladder, and then exposing the assembled and inflated structure to a suitable elevated temperature until the fibers and resins are bonded into unitary or monolithic whole. Alternatively, grip 22R may be molded from any suitable plastic material, such as polypropylene, using conventional molding techniques such as injection, blow, or rotational molding.

The advantage of making grip 22R from molded composite materials is that it allows the latter to be constructed as a load bearing hollow shell having a complex shape and an approximately uniform thickness. This load bearing shell, which may properly be referred to as a "monocoque" shell, allows grip 22R to exhibit a structural rigidity and integrity which is comparable to a grip that is composed of a metal, and yet has been formed into a shape that is not practical with metals and has a weight that is lower than that of a metal grip of similar size and strength.

Because of its high strength and low weight, grip 22R can be made larger than previously available grips, while maintaining a weight which is less than or equal to the weight of such grips. This larger size, in turn, enables the grip of the invention to be held in a rider's hand with a less tightly clenched or relatively more "open" grasp. More particularly, this larger size allows the grip to be held in a grasp in which the rider's fingers do not encircle the grip and touch the rider's palm, and in which the thumb does not rest on or touch the adjacent fingers. Because a relatively tight grasp requires that the muscles of the hand be held under a higher degree of tension than a relatively more open grasp, it will be seen that the design, fabrication techniques and materials used in constructing the grip of the invention allow the grip to be used with reduced hand and/or arm fatigue, without incurring the weight penalty associated with the use of previously known grips. This larger size also helps to distribute and thereby reduce the effect of the shock loads that are transferred to the human hand during off-road riding.

While the monocoque structure of grip 22R assures a high structural integrity throughout distal portion 24R thereof, the hollow proximal portion 26R thereof is relatively weak in compression, particularly in the region where it is attached to the end of handlebar segment 10R. This is because the latter region includes at least one opening for receiving the mechanism by which the grip is attached to handlebar H. (The latter opening may also serve as an access port to permit the removal of the inflatable bladder or other compression device that is

used during the curing of the grip.) This opening weakens the structural integrity of the grip by interrupting the continuity thereof at the point where manual steering forces applied to the grip must be transmitted to the end of the handlebar.

To the end that steering forces applied to the grip may be transmitted to the handlebar without damaging the grip, the bar end of the invention includes an improved fastening mechanism and insert which allow relatively concentrated forces to act between the fastening mechanism and the handlebar, and relatively distributed fastening forces to act between the insert and the grip. As will be explained more fully presently, this insert has an outer end section which is adapted to be fastened to two oppositely disposed surfaces of the proximal portion of the grip, and an inner end section which is adapted to be fastened to the end of the handlebar. The outer end of this insert serves both as a separating member which prevents the inner and outer surfaces of the grip from being pushed toward one another, and as a force distributing member which distributes the forces acting between the handlebar and the grip over a relatively large area at the proximal end of the grip. The inner end of the insert, on the other hand, acts as a conventional high strength fastener which is adapted to apply between itself and the handlebar as much fastening pressure as may be required to assure that the bar end remains securely fastened to the handlebar.

Referring to Figs. 3A and 3B there are shown respective enlarged, exploded, partially cutaway end and fragmentary side views of one embodiment of a

fastening mechanism 30R suitable for use in practicing the present invention. In the embodiment of Fig. 3A fastening mechanism 30R operates in conjunction with an insert 40R having an outer end 42R that is adapted to be connected to proximal end 26R of grip 22R. Insert 40R also includes an inner end 43R that is adapted to be connected to the right end of handlebar H. In the embodiment of Fig. 3A the outer end 42R of insert 40R includes an inner flange 44R which abuts the inner exterior surface of grip end 26R, and an outer flange 46R which abuts the outer exterior surface of grip end 26R. The latter flanges are preferably formed on opposite ends of respective insert segments 42R1 and 42R2, while the adjacent ends thereof are shaped to form an interlocking end-to-end joint 48R within the interior of grip end 26R. During assembly, insert segments 42R1 and 42R2 are passed through respective oppositely disposed openings in the body of grip end 26R until they assume the interlocked position shown in Fig. 3A. The lengths of these abutting segments is selected so that, as they assume this position, inner and outer flanges 44R and 46R simultaneously abut the adjacent exterior surfaces of grip end 26R. Because of the dimensional relationship between the parts of insert segments 42R1 and 42R2, outer end 42R of insert 40R accurately fixes the spacing between the inner and outer walls of grip end 26R, and prevents the application thereto of a force which tends to push those walls inwardly toward one another.

In order that insert 40R may transmit steering forces between grip end 26R and handlebar H, flanges 44R and 46R are preferably fastened to the abutting

exterior surfaces of the grip by a cured body of a suitable curable resin disposed therebetween. This body of resin, which may be of any of a variety of types well known to those skilled in the art, serves both to set the separation between the inner and outer walls of grip end 26R at a value equal to the separation between flanges 44R and 46R, and to distribute the force therebetween over the relatively large area surrounding the openings through grip end 26R. Thus, insert 40R will be seen to provide the previously described separating and force distributing functions.

In the embodiment of Fig. 3A, inner end 43R of insert 40R includes a sleeve 45R which is adapted to fit over the end of handlebar H and a stop or shoulder 47R which is adapted to abut the end of handlebar H. When inner end 43R is positioned over the end of handlebar H, stop 47R determines the depth to which the end to the handlebar extends into the interior thereof, and sleeve 45R provides a surface against which the handlebar may be clamped to assure that bar end 20R remains securely attached to handlebar H.

One fastening mechanism that is suitable for use in securing bar end 20R to handlebar H includes an expandable nut 49R, a wedge nut 51R and a tightening bolt 53R. During installation, the fastening mechanism is partially assembled by passing bolt 53R through an untapered centrally disposed hole 55R through insert 40R and a tapered centrally disposed hole 57R through expandable nut 49R, and threading it into wedge nut 51R. This partially assembled mechanism is then connected to handlebar H so that the end of the latter is

positioned between expandable nut 49R and sleeve 45R with its end resting against stop 47R. The installation is then completed by tightening bolt 53R, causing expandable nut 49R to expand and clamp the end of the handlebar against the inner surface of sleeve 45R. Because the fastening action of wedge nuts and expandable nuts are well known to those skilled in the art, this fastening action will not be further described herein.

Prior to the present invention the use of a fastening mechanism including a wedge nut and an expandable nut has been limited to structures which are resistant to the high longitudinal compressive forces produced thereby. In accordance with the present invention this limitation is overcome by using the wedge nut and expandable nut in combination with an insert, such as 40R, which serves as a buffer to relieve the element associated therewith from these longitudinal compressive forces. This combination, in turn, makes possible the construction of a bar end that includes a grip that is thin and light in weight, but which may be tightly clamped against a handlebar.

Referring to Figs. 4A and 4B, there are shown respective enlarged, fragmentary, partly cutaway end and enlarged fragmentary side views of a second embodiment of the bar end of the invention. The embodiment of Figs. 4A and 4B is broadly similar to that of Figs. 3A and 3B, corresponding parts being similarly numbered, except for the addition of a prime (') to the identifying labels used in Figs. 4A and 4B. Proximal end 26R' of the grip of Fig. 4A, for example, corresponds to proximal end 26R of the grip of Fig. 3A, except that it includes an

insert receiving opening only through the inner wall thereof. Similarly, outer end 42R* of insert 40R' of Fig. 4A corresponds to outer end 42R of insert 40R of Fig. 3A,except that it has a flat end surface 46R' which abuts and is bonded to the inner surface of the outer wall of the grip end, rather than a flange which abuts and is bonded to the outer surface of the outer wall of the grip end. Because of this similarity, the structural relationships between the outer end 42R' of insert 40R' and the proximal end 26R' of the grip will not be described in detail herein.

There are, however, two noteworthy differences between the fastening mechanisms that the embodiments of Figs. 3A-3B and 4A-4B use to fasten the respective bar ends to handlebar H. One of these is that, in the embodiment of Figs. 3A-3B, this fastening mechanism has a tightening bolt that is aligned with the longitudinal axis of the handlebar and clamps the bar end thereto from the inside via an expandable nut. In the embodiment of Figs. 4A-4B, on the other hand, the fastening mechanism has a tightening bolt that is generally perpendicular to the longitudinal axis of the handlebar and clamps the bar end thereto from the outside via a contractable collet or bifurcated sleeve 45R'.

A second of these is that, in the embodiment of Figs. 3A-3B, the proximal end 26R of the grip is protected from the compressive force produced by the tightening of fastening mechanism 30R by interlocking segments 42R1 and 42R2 of outer end 42R of insert 40R. In the embodiment of Figs. 4A-4B, on the other hand, proximal end 26R' of the grip is protected from the torsional shearing force

produced by the tightening of fastening mechanism 30R' by the length of the sleeve 45R' at the inner end of insert 40R'.

In spite of the above-discussed differences, the structure and function of the insert and fastening mechanisms of the embodiment of Figs. 4A-4B is broadly similar to that of the embodiment of Figs. 3A-3B. Accordingly, the structure and operation of the embodiment of Figs. 4A-4B will not be further described herein.

In view of the foregoing, it will be seen that the bar end of the present invention embodies a number of improvements over previously known bar ends. Firstly, it includes an ergonomically designed grip having a shape which has a comfortable "feel", in spite of its relatively hard surface, and having a size which allows it to be used with a relatively open grip that lessens hand and/or arm tension. Secondly, it includes a grip having a relatively thin, single piece, load bearing shell which combines lightness of weight with high structural integrity. Finally, the bar end of the invention includes insert and fastening mechanisms which allow the grip portion of the bar end to transmit high magnitude steering forces to a handlebar while protecting the grip from loading forces high enough to threaten its structural integrity.

It will be understood that, while the foregoing description makes reference to a number of specific embodiments, the true spirit and scope of the present invention should be determined only with reference to the appended claims.