Abstract:
A device comprises an outer sleeve and an inner sleeve that is rotatably supported at least partly in an interior of the outer sleeve. A hollow axle is located in an interior of the inner sleeve, and a skewer is supported within an inner region of the hollow axle. The skewer is slidable along an axis of hollow axle. First and second slots are located on the hollow axle. A lever that is rotatable about the axis of the hollow axle includes a mechanism for causing the rod to slide along the axis to change respective widths of the slots.

Description:
BACKGROUND 
     Electrically powered bicycles, or eBikes, use electric power to assist a user in pedaling a bicycle (a so-called “power-assist” function) or may use allow operation of the eBike solely with an electric motor. In any case, e-bikes generally include batteries that must be charged to operate. Charging typically requires plugging the eBike into an electrical outlet. Some eBikes include generators that allow the eBikes to be recharged, for example, during braking operations. However, such mechanisms do not typically generate significant amounts of power. Accordingly, improved mechanisms for charging eBikes are needed. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view of an exemplary eBike towing and charging system. 
         FIG. 2  is a perspective view of an exemplary towing device. 
         FIG. 3  is another perspective view of the exemplary towing device of  FIG. 2 , showing a clamp lever in a relaxed position. 
         FIG. 4  is another perspective view of the exemplary towing device of  FIG. 2 , showing the clamp lever in a tightened position. 
         FIG. 5  is an exploded view of the exemplary towing device of  FIG. 2 . 
         FIG. 6  is a perspective view of a skewer assembly. 
         FIG. 7  is a view of the skewer assembly end cap along the cross-section A-A of  FIG. 6 . 
         FIG. 8  is a perspective view of a clamp lever. 
     
    
    
     DETAILED DESCRIPTION 
     In the Figures, like numerals indicate like parts throughout the several views.  FIG. 1  illustrates a towing system  11  including a towing device  10  attached to a vehicle  12  for towing an electrically powered or power-assisted bicycle, i.e., eBike  14 . The eBike  14  includes a rear wheel  13  and a motor to drive the rear wheel  13  when the eBike  14  is operating in a power-assist mode. 
     When the eBike  14  is towed behind the vehicle  12 , the motor may be used to generate electrical power based on the rotation of the rear wheel  13  of the eBike  14  when the eBike  14  is being towed. The eBike  14  may be programmed in a charging mode. In the charging mode, the motor may be configured to generate electrical power when driven by rotation of the rear wheel  13 . The rear wheel  13  may rotate due to frictional contact with the road surface during towing. The power generated by the motor may be stored in a battery of the eBike  14 . In this manner, the towing device  10  may facilitate charging of the eBike  14  while the eBike  14  is being towed by the vehicle  12  Moreover, as described below, the towing device  10  allows the eBike  14  to be towed behind the vehicle  12  in a manner that accommodates vertical movement of the vehicle  12 , e.g., caused by bumps and the like in a roadway. 
     With reference to  FIGS. 2-5 , the towing device  10  includes a hitch connector arm  16  that is generally dimensioned, and provided with an opening  17 , for connection to a standard vehicle trailer hitch in a conventional manner, e.g., the opening  17  may receive a lock pin or the like (not shown). 
     The connector arm  16  has a supporting arm  18  mounted thereon, e.g., via welds, bolts, or some other conventional attachment mechanism. The supporting arm  18  generally extends upward at a right or obtuse angle from the connecting arm  16 . A clamp assembly  20  is mounted on an end of the supporting arm  18  that is distal with respect to the connecting arm  16 . For example, a substantially cylindrical outer sleeve  22  may be welded or the like to the distal end of the supporting arm  18 . 
     As best seen in  FIG. 5 , the clamp assembly  20  includes a skewer assembly  41  including an end cap  46  on a proximal end and a skewer  48  extending from the end cap  46 . The skewer  48  is a cylindrical rod providing a support structure for the clamp assembly  20  and includes a threaded end  49 , at an end distal from the end cap  46 . 
     A lever  24  is supported on the skewer assembly  41  on the proximal end adjacent to the end cap  46 . An opening  29  of the lever  24  receives the end cap  46 . 
     A hollow axle  28  forms a substantially cylindrical inner region  34  for receiving the skewer  48  of the skewer assembly  41 . The hollow axle  28  is positioned within a substantially cylindrical interior of a substantially cylindrical inner sleeve  26 , the inner sleeve  26  in turn being inserted in the substantially cylindrical interior of the outer sleeve  22 . The inner sleeve  26  includes reduced diameter portions  30  that are substantially cylindrical. The hollow axle  28  has a generally U-shaped outer surface at fork receiving portions  32 , i.e., the portions or ends  32  are shaped to receive a fork of a bicycle such as the eBike  14 . A portion of the hollow axle  28  within the sleeve  26  may have a generally circular, rectangular, or other cross-section. 
     Each of a pair of bearings  36  are generally cylindrical, having inner surfaces dimensioned to fit over a central portion  27  of the inner sleeve  26 . Reduced diameter portions of the inner sleeve  26  are provided at respective first and second ends of the central portion  27 . The bearings  36  further have an outer circumference dimensioned to fit within an interior surface of the outer sleeve  22 . The bearings  36  are held in place by lock collars  38 , a position of each of the collars  38  on a reduced diameter portion  30  of the inner sleeve  26  being maintained when a set screw  40 , threadably inserted into an opening of the collar  38 , is tightened. Further mounted on each of the reduced diameter portions  30  is a spacer  42 , the spacer  42  being provided to appropriately dimension a slot  45  configured to receive a bicycle fork piece. The bearings  36  allow the inner sleeve  26  to rotate with respect to the outer sleeve  22 , which as noted above, is fixedly mounted on the arm  18 . 
     As is best seen in  FIGS. 3 and 4 , a first slot  45  is provided between one of the spacers  42  and a side of the lever  24 . A second slot  45  is provided between an adjustor cap  44  and a second one of the spacers  42  at an opposite end of the inner sleeve  26  and hollow axle  28  from the first spacer  42  and the first slot  45 . The adjustor cap  44  is screwed onto the threaded end  49  of the skewer  48 . As described further below, the skewer  48  is slidable along a common longitudinal axis of the skewer  48 , hollow axle  28  and the sleeves  22 ,  26 , thereby facilitating narrowing of slots  45  when the lever  24  is moved from an open position to a closed position. 
     As can be seen by a comparison of  FIG. 3  and  FIG. 4 , the lever  24  may be moved from an open, or relaxed, position ( FIG. 3 ) to a closed, or tightened, position ( FIG. 4 ). As described further below, the lever  24  when moved to the tightened position, is urged toward an opposing spacer  42 , thereby reducing a width of the slot  45  formed by the spacer  42  and washer  43 . At the same time, the lever  24  is configured, when moved to the tightened position, to urge the skewer  48  in an axial direction toward the proximal end cap  46  such that the slot  45  formed by the adjustor cap  44  and second spacer  42  is made narrower. Further, the adjustor cap  44  may be moved to adjust a width of the slot  45 , typically when the lever  24  is in the relaxed position, by turning the cap  44  on the threaded end  49  of the skewer  48 . Accordingly, when a bicycle fork piece is placed in a fork receiving portion  32 , and the lever  24  is moved from an opened to a closed position, sides of each slot  45  are secured against respective bicycle fork pieces, which are then held in place by friction. As can be seen in  FIG. 4 , a gap  47  is formed between a side of the lever  24  and a side of a cap end section of the end cap  46  when the lever is in the closed position. 
       FIG. 6  provides a perspective view of the skewer assembly  41 . As described above, the skewer assembly  41  includes the end cap  46  and the skewer  48  extending from the end cap  46 . The skewer  48  is generally a cylindrical rod, and has a threaded end  49  opposite the end cap  46 . 
     The end cap  46  includes various sections  50 ,  54 , and  58  all being generally cylindrical but having different diameters.  FIG. 7  provides a cross-sectional view of the end cap  46 . A skewer connecting section  48  has a first diameter smaller than a second diameter of a helical threaded section  50 , which in turn has a diameter smaller than a third diameter of a pawl section  54 , the pawl section  54  including a pawl  56 . The third diameter is in turn smaller than a fourth diameter of the end section  58 . A helical outer thread  51  is formed on an outer surface of the helical threaded section  50 . The helical outer thread  51  is configured to threadably engage a helical inner thread  68  on the lever  24 , as described below with reference to  FIG. 8 . 
     As seen in  FIG. 6 , the end section  58  may include a cylindrical lock  59  for use with a tubular key (not shown). The lock  59  generally operates in a known manner. For example inserting the tubular key into the lock  59  may cause the pawl  56  to retract into the pawl section  54 , the pawl  56  being spring-mounted or the like on the pawl section  54 . Thus, when the pawl  56  is engaged by a pawl slot  64  in the level  24  (discussed below concerning  FIG. 8 ), the tubular key may be used to allow disengagement of the pawl  56 , and movement of the lever  24  from the closed to the open position. 
     Turning now to  FIG. 8 , the lever  24  typically includes a cylindrical portion  25  and a handle portion  27 . The cylindrical portion  25  includes an opening  29  having an interior surface defined by two generally cylindrical sections  62  and  66  having first and second diameters, respectively. A pawl section  62  includes a pawl slot  64  that is dimensioned to receive the pawl  56  of the end cap  46 . An inner surface of a helical thread receiving section  66  has a helical inner thread  68  defined thereon. The helical inner thread  68  is configured to receive the helical outer thread  51  of the end cap  46 . Accordingly, when the skewer assembly  41  is inserted into the opening  29 , the helical outer thread of the end cap  46  can threadably engage the helical inner thread  68  of the lever  24 , and the lever  24  may be screwed onto the end cap  46 . As described above, rotation of the lever  24  with respect to the end cap  46 , as well as the hollow axle  28  and inner sleeve  22 , causes the skewer  48  to slide in an axial direction as mentioned above, thereby narrowing slots  45  and, if fork pieces or the like of the eBike  14  are placed in the slots  45 , securing the fork pieces. Further, as the lever  24  is moved to a closed position, spring action as described above may cause the pawl  56  to engage and lock in the pawl slot  64 . 
     As used herein, the adverb “substantially” means that a shape, structure, measurement, quantity, time, etc. may deviate from an exact described geometry, distance, measurement, quantity, time, etc., because of imperfections in materials, machining, manufacturing, etc. 
     In the drawings, the same reference numbers indicate the same elements. Further, some or all of these elements could be changed. With regard to the components, processes, systems, methods, etc. described herein, it should be understood that these are provided for the purpose of illustrating certain embodiments, and should in no way be construed so as to limit the claimed invention. 
     Accordingly, it is to be understood that the above description is intended to be illustrative and not restrictive. Many embodiments and applications other than the examples provided would be apparent to those of skill in the art upon reading the above description. The scope of the invention should be determined, not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. It is anticipated and intended that future developments will occur in the arts discussed herein, and that the disclosed systems and methods will be incorporated into such future embodiments. In sum, it should be understood that the invention is capable of modification and variation and is limited only by the following claims. 
     All terms used in the claims are intended to be given their plain and ordinary meanings as understood by those skilled in the art unless an explicit indication to the contrary in made herein. In particular, use of the singular articles such as “a,” “the,” “said,” etc. should be read to recite one or more of the indicated elements unless a claim recites an explicit limitation to the contrary. 
     The disclosure has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the present disclosure are possible in light of the above teachings, and the invention may be practiced otherwise than as specifically described.