Abstract:
A compression coupler contains a robust and simple mechanism to couple threadless tubes in bicycles and/or scooters. Particulrly, the handlebar/stem tube-to-fork joint is coupled with a compression sleeve. The coupler provides more surface area for binding and is tightened along a slot on the length of the coupler. The coupler can include a headtube bearing preloading mechanism, a keyway for aligning the handlebar/stem tube to the fork, and shims to accommodate different sized tubing.

Description:
I. FIELD 
     The present disclosure is directed to the field of mechanical couplers for differently sized diameter objects. More particularly, it is directed to a compression based coupler for robustly binding together the handle bar stem and fork tube of a bicycle or kick style scooter. 
     II. BACKGROUND 
     Non-motorized scooters, particularly of the sort typified by kick scooters are rapidly entering competitive circles for stunt performances and other extreme forms of competition. Most popular of the kick scooters is the Razor® scooter. The force of activities on a typical scooter will often result in various parts of the scooter to fail. As can be imagined, because of the inherent danger of these stunts, a failed scooter component can result in serious injury to the rider. Therefore, there has been an increasing interest in ruggedizing various components of the scooter. 
     One particular area where little attention has been devoted is the joint between the stem of the handle bars and the fork of the front wheel. No one has successfully devised a coupling mechanism that secures the stem-to-fork joint from breaking or severing under extreme loads. In view of this deficiency, various systems and methods are disclosed herein that provide a simple and yet robust solution to the stem-to-fork joint problem for bicycles, or kick scooters. 
     SUMMARY 
     The following presents a simplified summary in order to provide a basic understanding of some aspects of the claimed subject matter. This summary is not an extensive overview, and is not intended to identify key/critical elements or to delineate the scope of the claimed subject matter. Its purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is presented later. 
     In one aspect of the present disclosure, a clamp for binding a handlebar stem tubing to a fork tubing on a bicycle or scooter is provided, comprising, a longitudinal compression sleeve body; a first bore of a first diameter disposed at an end of the body; a second bore of a second diameter disposed at an other end of the body, wherein the first bore and the second bore meet within the body to form a circular lip defined by a difference in the first diameter and second diameter; a longitudinal slot disposed from the first end to the other end of the body, providing a gap from the first and second bore to an exterior of the body; and a tightening mechanism disposed about a portion of the body, wherein as the tightening mechanism is engaged, a handlebar stem tubing end placed within the first bore and a fork tubing end of different diameter, placed within the second bore, is secured to the body. 
     In another aspect of the present disclosure, a method for binding a handlebar stem tubing to a fork tubing on a bicycle or scooter is provided, comprising, placing a fork tubing end into a first diameter bore hole at an end of a compression sleeve body having a second diameter bore hole at an other end of the body, wherein the first bore hole and the second bore hole meet within the body to form a circular lip defined by a difference in the first and second diameters, the body further having a longitudinal slot externally disposed from the first end to the other end of the body communicating to the first and second bore hole; placing a handlebar stem tubing end into the second diameter bore hole at the other end of the body; and tightening a securing mechanism disposed about a portion of the body to secure the fork tubing and handlebar stem tubing to the body. 
     In another aspect of the present disclosure, a compression clamp for binding a handlebar stem tubing to a fork tubing on a bicycle or scooter is provided, comprising, a longitudinal compression sleeve body; a first bore of a first diameter disposed at an end of the body; a second bore of a second diameter disposed at an other end of the body, wherein the first bore and the second bore meet within the body to form a circular lip defined by a difference in the first diameter and second diameter; a longitudinal slot disposed from the first end to the other end of the body, providing a gap from the first and second bore to an exterior of the body; and means for tightening the handlebar stem tubing and the fork tubing to the body, disposed about a portion of the body. 
     In another aspect of the present disclosure, a compression clamp for binding a handlebar stem tubing to a fork tubing on a bicycle or scooter is provided, comprising, a longitudinal compression sleeve body; a single bore disposed through the body; a longitudinal slot disposed from a first end to an other end of the body, providing a gap from the bore to an exterior of the body; and a compression washer integral to the body and horizontally disposed at a near longitudinal mid-point of the bore, capable of accommodating a compression bolt, wherein as the tightening mechanism is engaged, a handlebar stem tubing end placed within the first bore and a fork tubing end of different diameter, placed within the second bore, is secured to the body. 
     To the accomplishment of the foregoing and related ends, certain illustrative aspects are described herein in connection with the following description and the annexed drawings. These aspects are indicative, however, of but a few of the various ways in which the principles of the claimed subject matter may be employed and the claimed subject matter is intended to include all such aspects and their equivalents. Other advantages and novel features may become apparent from the following detailed description when considered in conjunction with the drawings. As such, other aspects of the disclosure are found throughout the specification. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The features and nature of the present disclosure will become more apparent from the detailed description set forth below when taken in conjunction with the drawings in which reference characters identify corresponding items and processes throughout. 
         FIG. 1  is an illustration of a kick scooter with an exemplary coupling attached thereto. 
         FIG. 2  is an expanded view illustration of an exemplary coupling embodiment. 
         FIGS. 3A-B  are front and cross-sectional views of an exemplary coupling embodiment. 
         FIGS. 4A-E  are left, top, right, bottom and front views of an exemplary coupling embodiment. 
         FIGS. 5A-C  are perspective view, front and cut-away views of an exemplary embodiment. 
         FIGS. 6A-C  are perspective views of exemplary embodiments with varying number of attachment means. 
         FIG. 7  is a perspective view of another exemplary embodiment with an attachment mechanism. 
     
    
    
     DETAILED DESCRIPTION 
     The disclosed methods and systems below may be described generally, as well as in terms of specific examples and/or specific embodiments. For instances where references are made to detailed examples and/or embodiments, it should be appreciated that any of the underlying principals described are not to be limited to a single embodiment, but may be expanded for use with any of the other methods and systems described herein as will be understood by one of ordinary skill in the art unless otherwise stated specifically. 
       FIG. 1  is an illustration of a freestyle kick scooter  10  with an exemplary compression coupling  16  attached thereto. An exemplary compression coupling  16  is externally mounted to a threadless stem-to-fork joint and spans a greater surface area of the stem  14  and fork (shown internal to head tube  18 ) resting on headset bearings  17 . Handlebar alignment channel  15 , as further described below, is shown on the bottom of stem  14 . With more secured surface area, the exemplary coupling  16  provides a simple and robust coupling mechanism, enabling stunt activities to performed without fear of separation of the stem-to-fork joint. Various details of exemplary embodiments of the compression coupling  16  are expounded upon below. 
       FIG. 2  is an illustration of an expanded view of an exemplary compression coupler  20 , having optional threaded compression bolt  25 , compression washer  29  and threaded fork insert  27 . The exemplary compression coupler  20  of this embodiment is shown as an open ended compression sleeve  31  having an inner opening  32  with an interior profile (not shown) of two different bore diameters for matching differently sized stem and fork tubing, and a compression accommodating gap  33 . Optional keyway  34  is provided in opening  32  for an optional alignment key  35  to allow aligning the tubings, as further detailed below. 
     A series of bolts  38  for tightening the compression accommodating gap  33  of the exemplary compression coupler  20  are shown with matching holes  36  distributed along the axis of the compression sleeve  31 . Though the bolts  38  are illustrated as having hexagonal keyed heads (e.g., Allen heads) for tightening (to nuts or threads, not shown) by a hexagonal wrench (e.g., Allen wrench), any bolt type/style or tightening mechanism may be used without departing from the spirit and scope of this disclosure. Accordingly, the bolts  38  may be screws, threaded, non-threaded, or any mechanism that provides a tightening capability. In some embodiments, after applying an arbitrary mechanism to tighten the compression accommodating gap  33 , a rivet may be utilized to prevent the compression accommodating gap  33  from being “untightened.” 
       FIG. 3A  is a view of an exemplary compression coupler  20  attached to a stem  22  and fork  24  at a near mid-point of the exemplary compression coupler  20 .  FIG. 3B  is a cross-sectional view along the cut line A-A of  FIG. 3A , showing the different diameters of stem  22  and fork  24 . The profile of the interior side of the exemplary compression coupler  20  is generally symmetric, whereas the right side is not visible due to cut line A-A being centered through optional keyway  34 . However, if stem  22  and fork  24  are smaller in diameter than the inner bore diameters of the exemplary compression sleeve  20 , an appropriately sized shim can be inserted, as detailed below. 
     Referring back to  FIG. 1 , in some scooters, a channel  15  of a predetermined depth will be longitudinally cut into the stem and the fork for use as handlebar alignment registration to align the stem (and by inference, the handlebars) with the fork. This handlebar alignment channel  15  is typically cut into the “front” of both the stem and fork. By aligning the optional keyway  34  with the handlebar alignment channel  15 , the alignment key  35  can be placed into the handlebar alignment channel and into the aligned optional keyway  34 , to constrain rotation of the stem from the fork, when the exemplary compression coupler  20  is tightened. 
     By use of an appropriately sized alignment key  35  in concert with optional keyway  34 , the exemplary compression coupler  20  can be used to easily align a stem and fork tubing. Of course, in some embodiments, the optional keyway  34  or alignment key  35  may not be necessary, depending on the alignment mechanism provided in the stem and fork. 
     As shown, optional threaded compression bolt  25 , compression washer  29  and threaded fork insert  27  can be utilized to further assist in restraining the exemplary compression coupler  20  to the fork  24 . In operation, compression washer  29  is placed on top of a lip  30  formed by the junction of different bore holes in the exemplary compression clamp  20 . The threaded compression bolt  25  is then engaged with the threaded fork insert  27  and tightened to cause expansion legs  27   a  of threaded fork insert  27  to be pulled against the fork  24 , thus securing the exemplary compression clamp  20  (joined by threaded compression bolt  25  and compression washer  29 ) to fork  24  (joined by threaded fork insert  27 ). 
     It should be appreciated that while the threaded fork insert  27  is shown with expansion legs  27   a , any lateral force inducing apparatus may be utilized. Therefore, modifications to the type of threaded fork insert  27  and associated elements are understood to be within the purview of one of ordinary skill in the art. 
     It is also understood that in most embodiments, an air gap of some sort between the compression washer  29  and the fork  24  is necessitated, to allow the fork  24  to freely move slightly upward as it is being engaged by the threaded fork insert  27 , particularly for preloading purposes. Specifically speaking, the optional threaded compression bolt  25 , compression washer  29  and threaded fork insert  27  can be used to “pre-load” the headset bearings  17  (see  FIG. 1 ). By way of example, when the exemplary compression coupler  20  is fitted onto the scooter, the optional alignment key  35  can be used to keep all the components in line with each other. When the stem  22  is removed from the top bore hole of the exemplary compression coupler  20 , the threaded compression bolt  25 , compression washer  29  and threaded fork insert  27  can be inserted into the top bore of the exemplary compression coupler  20 , with the compression washer  29  resting on a lip  30  formed by the junction of the two diameter bores in the exemplary compression coupler  20 . Thereafter, the threaded compression bolt  25  can be tightened against the threaded fork insert  27  to cause the fork  24  to be pulled toward the compression washer  29 , resulting in preloading the headset bearings  17  and removing undesired looseness from the headset bearings  17 . Once the appropriate looseness is removed, the stem  22  can be placed into the top bore of the exemplary compression coupler  20  and tightened via the threaded bolts  38 . 
     It should be appreciated that in some embodiments, it may be desirable to have the threaded compression bolt  25 , compression washer  29  and threaded fork insert  27  fixed in the exemplary compression coupler  20 . That is, rather than being an optional fixture, the compression washer  29  may be milled or fabricated as an integral, fixed part of the exemplary compression coupler  20 , with the threaded compression bolt  25  and threaded fork insert  27  attached thereto. Therefore, where headset bearing loading is desired, in some embodiments the exemplary compression coupler  20  may come pre-configured with the compression washer  29 . 
     In some embodiments, the compression washer  29  may not rest on a lip  30 , but in an exemplary compression coupler  30  that has a single bore diameter throughout, be positioned at a near mid-point of the bore. Therefore, in this instance, without a lip  30  to rest on, the compression washer  29  may be fabricated to be integral to the exemplary compression coupler  30   
       FIGS. 4A-4E  are left, top, right, right, bottom and front views, respectively, of an exemplary compression coupler  20 . In  FIG. 4B  an optional circular shim  52  is inserted into the top of inner opening  32   a  and resting on lip  30 . Optional shim  52  provides a convenient mechanism to allow the exemplary compression coupler  20  to fit stem tubing that may be smaller in diameter than the respective bore of the exemplary compression coupler  20 . Also, an appropriately sized shim (not shown) may be utilized on the bottom opening  32   b  ( FIG. 4D ), if so desired. Shim  52  is shown with gap  54  to allow the shim  52  to compress as the exemplary compression coupler  20  is tightened. As evident in the bottom view, the opening  32   b  is of a smaller diameter than the opening  32   a  in the top view. This is consistent with the practice of scooter manufacturers using a larger tube size for the stem than the fork. 
       FIGS. 5A-C  are perspective, front and cut-away views of additional embodiments of an exemplary compression coupler  20  having a built in compression washer  29   a , with a shim  52  having a slot for a multi-extensioned alignment key  35   a  having extensions  35   b  and  35   c .  FIG. 5C  illustrates the shim  52  with “upper”  52   a  and “lower”  52   b  cross sectional portions breeched by alignment key extension  35   b , and cross sectional portion  52   c  opposite the alignment key  35   a . The upper extension  35   b  of alignment key  35   a  can be used to align the stem while the lower extension  35   c  can be used to align the fork. These views illustrate the ability to craft a shim  52   a  with slots to allow alignment using the alignment key  35   a , as well as the ability to have a compression washer  29   a  as an integral part of the exemplary compression coupler  20 . 
       FIGS. 6A-C  are elevated perspective views of additional embodiments of the exemplary compression coupler, each having a different number of holes for tightening the exemplary compression coupler. It is noted that  FIG. 5B  shows the optional shim  52  inserted. These views illustrate the ability to vary the number of holes/threaded bolts, if so desired. Accordingly, as different number of holes may be used, it is understood that a completely different mechanism for tightening/attachment, other than the use of threaded bolts or the like, may be contemplated as within the scope of this disclosure. 
       FIG. 7  is a perspective view of another exemplary compression coupler  70  showing various other types of applicable attachment mechanisms. One attachment mechanism is non-threaded and is shown as a set of pull-binding/releasable clasps  68 . Though two pull-binding/releasable clasps  68  are shown, it is understood that more or less clasps may be implemented according to clasp design or binding strength preference.  FIG. 6  also illustrates the use of threaded set screws  74  and set screw holes  76  as a mechanism for alignment, the number of which and position may be varied, as desired. 
     As is apparent, innumerable types and kinds of attachment mechanisms known to one of ordinary skill in the art can be utilized, either individually or in combination. As another example of a suitable attachment mechanism well known in the bicycle arts is a “quick release” axle. Other modifications may be contemplated including altering the positions of the attachment mechanisms, as well as modifying the shape or size of the body  72  of the exemplary compression coupler body. 
     In view of the disclosure provided above, various modifications may be made to the exemplary embodiments without departing from the spirit and scope therein. For example, it is contemplated that the compression sleeve may be a machined product or a molded product, or even a combination of the two, if so desired. Therefore, the exemplary compression sleeve may be formed from a metal and/or plastic material, fiberglass, carbon-based, and so forth, depending on design preference. In the interests of minimizing weight, the exemplary compression sleeve may be manufactured from aluminum stock or other light metal, or even a suitable plastic material. Also, the exemplary compression coupler may be varied in size, having a thinner profile, or shorter height, according to design preference. 
     In various embodiments for ready use with current kick style scooters, the exemplary compression coupler may be designed to have a height of approximately one to six inches with an internal bore diameter of approximately 1⅛ inches progressing approximately 50% of the depth of the exemplary compression coupler. The remaining depth of the exemplary compression coupler contains another internal bore having an approximate diameter of anywhere between 1¼ to 1⅜ inches. The gap of the exemplary compression coupler may be accomplished with a vertical slot of anywhere from ⅛ to ⅜ inches. 
     The above dimensions are provided to illustrate that the exemplary compression coupler can be fitted to current kick style scooters, according to the standard tube dimensions current used by industry. The above dimensions are therefore illustrative and do not represent all the possible dimensions that may be used, as the appropriate dimensions are principally a function of the tubing sizes found on a scooter. Therefore, while various descriptions are provided in the context of a kick scooter, the exemplary compression coupler may be used for other man-powered vehicles. Accordingly, modification of the sizes may be made to accommodate the exemplary compression coupler to differently sized bicycle joints, as needed. 
     Also, it should be appreciated that while the various exemplary embodiments shown herein illustrate an interior profile of the exemplary compression coupler as having a “smooth” surface, non-smooth profiles or surfaces may be utilized without departing from the spirit and scope herein. For example, ridges, scoring, marking, and so forth may be applied to the interior profile of the exemplary compression coupler to provide an interior surface with increased gripping capabilities. Additionally, shim  52  may be differently sized, encompassing only a portion of the interior of the exemplary compression coupling. 
     What has been described above includes examples of one or more embodiments. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the aforementioned embodiments, but one of ordinary skill in the art may recognize that many further combinations and permutations of various embodiments are possible. Accordingly, the described embodiments are intended to embrace all such alterations, modifications and variations that fall within the spirit and scope of the appended claims. Furthermore, to the extent that the term “includes” is used in either the detailed description or the claims, such term is intended to be inclusive in a manner similar to the term “comprising” as “comprising” is interpreted when employed as a transitional word in a claim.