AXLES, SUCH AS FOR BICYCLES

Abstract

A suspension for a two-wheeled vehicle includes first and second fork legs. Each fork leg includes a dropout. Each dropout has an opening therethrough. At least a portion of one of the openings is threaded. Each of the dropouts includes a split-damp pinch bearing defining the opening and operable between an open position and a locked position, and a hand operable actuator pivoted to the bearing for operation thereof. The suspension further includes a one-piece axle. The axle is disposed through the openings. The axle has a threaded first end engaged with the threaded portion. The axle has an ergonomic grip formed at a second end. The bearing tightly engages an outer surface of the axle in the locked position, thereby rotationally coupling the axle to the dropout.

Claims

1. An axle assembly configured to be disposed within an opening of a first split-clamp pinch bearing of a first dropout of a suspension fork and within an opening of a second split-clamp pinch bearing of said suspension fork, said axle assembly comprising: an axle body, said axle body comprising: threads configured to be engaged with threads disposed on at least a portion of an interior surface of said first split-clamp pinch bearing; and a bore formed through said axle body; and a lever coupled to said axle body; a grip portion, said grip portion including a recess formed therein for stowing said lever; and wherein said first split-clamp pinch bearing and said second split-clamp pinch bearing are configured, when in a locked position, to clamp said axle body within said first split-clamp pinch bearing and within said second split-clamp pinch bearing, thereby preventing said axle body from un-threading from said first split-clamp pinch bearing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG. 1 depicts a cross-section of an axle according to an exemplary embodiment of the invention.

[0023] FIGS. 2A, 2B, and 2C depict an exemplary use for the exemplary axle of FIG. 1.

[0024] FIG. 3 is a high-level block diagram indicating an exemplary method for making the exemplary axle of FIG. 1.

[0025] FIG. 4A and FIG. 4B depict the enlarged portion of the axle body after the first forging step.

[0026] FIG. 5A and FIG. 5B depict solid and cross-sectional views, respectively, of the axle body after the second forging step.

[0027] FIG. 6 depicts the grip portion of the exemplary axle after some basic machining steps.

[0028] FIG. 7 depicts the complete axle (except for the lever) after final machining.

[0029] FIG. 8A and FIG. 8B depict an alternative embodiment of an axle according to the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

Introduction

[0030] This patent application describes the invention in the context of an exemplary embodiment of a front axle for a bicycle and how that exemplary axle is mounted to an exemplary front bicycle suspension fork. However, the teachings and scope of the inventionespecially as related to the manufacture of the axle body, itselfare equally applicable to a front or rear wheel of any two-wheeled vehicle.

Basic Axle Structure

[0031] FIG. 1 depicts a cross-section of an axle assembly 10 according to an exemplary embodiment of the invention. Axle assembly 10 includes an axle body 11 having a first end 12 and a second end 13 connected by an elongated tubular body portion 15. The inner wall 15 of tubular body portion 15 defines a through bore 15a. As will be described below, the first and second ends 12, 13, will be processed differently during the manufacture of axle body 11 and have different structures. However, they will still be parts of a unitary (one-piece) axle body. Positioned between the first end 12 and the second end 13 are a first bearing portion 16 and a second bearing portion 17 for mounting in first and second dropouts, respectively (see discussion of FIGS. 2A-2C below). As will be described below and for the beneficial reasons described below, according to the preferred embodiment of the invention, axle body 11 will be forged from a single solid metallic work piece. Typically, the metallic work piece will be a piece of aluminum. However, other materials may be used.

[0032] First bearing portion 16 includes threads 19 positioned adjacent the first end 12 of the axle body 11 and a smooth bearing surface 20 inwardly spaced from threads 19 and the first end 12 of axle body 11. Threads 19 are for mounting in complementary threads 101 in a corresponding threaded dropout 99 (see FIG. 2A).

[0033] Second bearing portion 17 includes an enlarged diameter (relative to the first bearing surface 20) smooth bearing surface 21 for insertion into a corresponding non-threaded and smooth dropout 98 (see discussion of FIGS. 2A-C below).

[0034] The second end 13 of axle body 11 includes an ergonomically designed grip portion 22. Grip portion 22 may include first and second opposed wings 23a, 23b, extending outward from the longitudinal axis of the axle body 11 beyond the bearing surfaces of axle body 11. Accordingly, under such conditions, the wings 23a, 23b would be the widest portion of axle body 11. As shown in FIG. 6, wings 23a, 23b have smoothened ends 24 and are shaped, such that in combination with sweeping curved surfaces 25, grip portion 22 is ergonomically shaped to be comfortable to hold and allow easy and comfortable tool-free mounting of axle assembly 10 to its corresponding dropouts.

[0035] A lever 26 may be provided for rotating axle assembly 10 about is longitudinal axis so that the threads 19 of axle assembly 10 may interlock with the threads of the dropout 99. Lever 26 may be pivotable (see curved arrow A-A of FIG. 1) about a fixed pivot point, such as a fastener 30, positioned on wing 23a, between at least first and second positions. In lever 26's first position (solid), lever 26 is in its operable position to assist in rotating axle assembly 10 about its longitudinal axis. In lever 26's second position (shadow), lever 26 has been pivoted into its stowed position in a lever recess 26 (see e.g. FIG. 6 for best view) and is retained in the stowed position by a clip ring 27.

[0036] In applications where tool-free mounting of axle assembly 10 is not important, as shown in FIG. 8A, 8B, it is possible to insert any known external tool T into a tool-receiving portion T defined by grip portion 22.

[0037] Whether lever 26 or an external tool T is used, grip portion 22 and tubular body 15 remain a one-piece axle body 11. This one-piece construction reduces production costs as well as opportunities for the axle components to separate when subjected to extreme forces. Thus, the current exemplary one-piece design is more robust and useful in high-stress applications than prior art multi-component designs.

Exemplary Use of Axle

[0038] FIG. 2A-2C depict an exemplary use for the exemplary axle assembly 10 of FIG. 1 and in the form of a bottom portion of an exemplary bicycle suspension fork. For clarity, such conventional components as the upper portions of the suspension fork, the tire, the wheel and other associated hardware have been omitted from FIGS. 2A-2C.

[0039] In FIG. 2A, the longitudinal axis of axle assembly 10 is aligned with the longitudinal axes of the dropouts 98, 99 of the suspension fork. In this exemplary embodiment, the dropouts 98, 99 include split-clamp pinch bearings 100, 100 in lower fork legs 110. Split-clamp pinch bearings 100, 100 substantially surround axle assembly 10 subject to small slits 102 formed by the space between opposing clamp ends 103, 103 that allow the diameters of the split-clamp pinch bearings 100, 100 to be varied to clamp or release axle assembly 10 within split-clamp pinch bearings 100, 100.

[0040] Split-clamp pinch bearing 100 will have a completely smooth bearing-like surface finish for engagement with smooth bearing surface 21 of axle assembly 10. Split-clamp pinch bearing 100 will have a partially smooth bearing-like finish for engagement with bearing surface 20 of axle assembly 10 and threads 101 complementary to threads 19. In FIG. 2A, cammed clamp levers 120 are in their open position allowing slits 102 to expand to allow axle assembly 10 to be inserted into split-clamp pinch bearings 100, 100.

[0041] In FIG. 2B, axle assembly 10 has been inserted through split-clamp pinch bearings 100, 100. Axle assembly 10 is then rotated, using for example, lever 26 (see arrow B) or ergonomically shaped grip portion 22 until the complementary threads 101 of split-clamp pinch bearing 100 capture axle threads 19. This may take approximately 2-3 turns of axle body 11 depending upon the pitch and length of the complementary threads 19, 101. Typically, the rider can feel when the axle threads 19 and the pinch bore threads 101 have become properly engaged.

[0042] In FIG. 2C, cammed clamp levers 120 are in their locked positions thereby decreasing the sizes of slits 102 by forcing opposing clamp ends 103, 103 towards each other. This clamps axle assembly 10 within each of the split-clamp pinch bearings 100, 100. Clamping prevents axle assembly 10 from un-threading itself when the fork and axle assembly 10 are subjected to various forces. Finally, lever 26 may be pivoted into its stowed position in lever recess 26. When lever 26 is stowed within lever recess 26, lever 26 will be substantially flush with the surface of the grip portion 22.

[0043] While the previous discussion has been in the context of installing the axle assembly 10, one skilled in the art would recognize that in the context of un-installing the axle assembly 10, the above process would merely be reversed.

Exemplary Method of Making the Axle

[0044] FIG. 3 is a block diagram depicting the major steps of an exemplary method for making the exemplary axle assembly 10 whose structure and use are described herein. As previously mentioned, most typically, the axle will be made from a metallic material, such as aluminum. Accordingly, a blank, such as a solid aluminum work piece, is provided.

[0045] Using, for example, conventional hammer forging machinery (not shown), a first portion of the solid blank will be forged into a solid enlarged portion 50 (see FIGS. 4A, 4B). Enlarged portion 50 will be shaped by the forging process to have the basic physical characteristics of finished grip portion 22, as described above. For example, solid enlarged portion 50 will be shaped by forging to have wing precursors 51, wing end precursors 52, and sweepingly curved side surface precursors 53.

[0046] Then, again using conventional hammer forging (or impact extrusion) machinery (not shown), a second portion of the same solid blank will be formed into tubular body portion 15. This early form of axle body 11 will have inner walls defining a through bore 15, but the through bore 15 will be closed off at second end 13 and enlarged portion 50 and open at first end 12 (See FIGS. 5A, 5B), i.e., axle body 11 is not yet open at both ends 12, 13.

[0047] Note that it may be possible to combine the two forging steps into one depending upon, for example, part complexity and sophistication of available machine shop equipment.

[0048] After forging, enlarged portion 50 is finally formed into finished grip portion 22, shaped as previously described above. To achieve this, the most basic 2D machining methods can be used to finish manufacturing axle body 11. No complex 3D surface machining methods, which are typically expensive and tedious to program and implement, are needed. Additionally, if solid billet material was used according to prior art methods, a large amount of time would be spent removing material to achieve this axle diameter, due to the large diameter of the grip portion.

[0049] Thus, according to the exemplary method, for example, using conventional machine shop cutting tools, as shown in FIG. 6, the closed end of enlarged portion 50 can be opened up to form bore 55. This lightens axle body 11. Furthermore, again using simple end mills or woodruff-cutters, wing precursor 51, end precursor 52, and curved side precursor 53 will be machined into their final forms, which includes forming lever recess 26. Similarly using a drill and tap, pivot bearing 31 and threaded pivot hole 32, for receiving pivot fastener 30, may be formed.

[0050] Then, the outer diameter of the bearing portion 21 and the outer diameter of tubular body portion 15 are smoothened and dimensioned using, for example, basic 2D machine tools (not shown) and threads 19 may be cut into the surface of axle assembly 10 at its first end 12 (FIG. 7). Also, retaining groove 27 for clip ring 27 will be machined.

[0051] Finally, before attaching lever 26 to grip portion 20 via fastener 30, axle assembly 10 may be cleaned, de-burred, polished, and anodized, as well as treated according to any other known mechanical or chemical processing methods. Additionally, clip ring 27 will be installed into clip ring retaining groove 27.

CONCLUSION

[0052] While the invention has been described with respect to certain exemplary structural and method embodiments, the invention shall only be limited by the following claims.

TABLE-US-00001 31 pivot bearing 32 threaded pivot hole 50 solid enlarged portion 51 wing precursors 52 wing end precursors 53 side surface precursors 55 bore 98, 99 dropouts 100, 100 pinch bearings 101 threads 102 slits 110 lower fork legs 120 cammed clamp levers