Abstract:
There is disclosed a device for connecting a lead bicycle and a trailing bicycle into a tandem configuration consisting of first and second connectors attachable to, for example, the seat post of the lead bicycle and to the head post or frame of the trailing bicycle, respectively; a telescoping linking bar releaseably attachable to the two connectors, the linking bar having a section that allows a limited amount of flexing longitudinal travel; wherein the linking bar connections permit horizontal, vertical and torsional rotation and which release and de-couple the bicycles when rotation exceeds predetermined limits, which may occur when one bicycle falls or the trailing bicycle begins to pass the lead bicycle.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The priority of U.S. Application No. 60/648,446 filed Feb. 1, 2005 is claimed. 
     BACKGROUND OF THE INVENTION 
     Two bicyclists of unequal ability often have difficulty staying together while riding. To remedy this situation, many cyclists couple their bicycles together in a tandem arrangement in order to combine efforts and stay together for all or a part of the ride. In the latter case, the bicycles may be decoupled later in the ride, enabling independent riding on the same trip. This situation is common not only for adults riding with children but also for adults riding with other adults of differing cycling ability. Currently, no convenient, lightweight, and safe device exists that provides coupling and decoupling capability when both riders weigh in excess of approximately 90 pounds. 
     A number of designs exist that permit a bicycle to pull a single-wheel type of trailer with handlebars for a small child to ride. See, for example, U.S. Pat. Nos. 5,067,738 and 5,470,088. While such designs may allow the child to peddle and contribute to the ride, they do not provide capability for the child to ride independently if desired. In addition, such designs have a weight limit that is typically below 90 pounds due to the imbalance that can occur with larger riders on the trailing device since the leading cyclist must provide balance for both riders. 
     U.S. Pat. No. 6,155,582 discloses a device for towing a child&#39;s bicycle in which the front wheel of the child&#39;s bicycle is lifted off the ground. This coupling device includes features for relatively quick removal and stowage of the device on the lead bicycle. However, this device also limits the weight of the child rider for the same reasons as the single-wheel trailer type design noted above. In addition, because the tow bar must bear a part of the load necessary to lift the front wheel of the trailing bicycle throughout the ride, the tow bar is necessarily relatively heavy and inconvenient to stow on the lead bicycle when not in use. 
     A number of devices for coupling two bicycles into a tandem configuration using a linking bar and flexible connection arrangement are known. See U.S. Pat. Nos. 4,261,592, 5,749,592, 6,036,215 and 6,286,847. However, these designs also have a significant drawback in that the linking bar is substantially nonextendable in its longitudinal axis. When two separate bicycles are ridden in alignment one behind the other at equal speeds, the position of one bicycle relative to the other continually changes along the longitudinal axis between the bicycles as each bicycle encounters slightly different road conditions. These changes in relative position along the longitudinal axis can be minor if road conditions are excellent, or very substantial under poor road conditions, e.g., when one bicycle rolls over a bump or a rut. Because a fixed linking bar does not allow flexibility and load-dampening along its longitudinal axis, each bicycle will transmit its own de-stabilizing axial forces directly to the other, creating a less stable and less comfortable ride and resulting in a potential crash when road conditions are poor. In addition, when the lead bicycle is turning sharply, it can be difficult for the trailing bicycle to follow directly behind the lead bicycle, particularly at higher speeds. When this occurs, the directions of travel of each bicycle can quickly diverge, creating a very unstable situation which usually results in both bicycles falling. Thus, this design does not provide for a means to decouple the bicycles or otherwise prevent such an unsafe situation. 
     U.S. Pat. No. 6,036,215 discloses a means of separating a tandem linking bar based on axial tensile forces exceeding a certain limit. However, this type design can result in an unintended separation when the lead bicycle rider is strenuously towing a heavily loaded trailing bicycle or is towing up a steep incline. Conversely, if the release force needed to separate is high enough to permit the linking bar to remain intact while towing a substantial load, this could have the unintended effect of not detaching should a smaller trailing bicycle and rider fall. 
     There is therefore a need in the art for a tandem bicycle coupling device with a combination of minimal weight, small profile, and quick. and easy engagement and disengagement that allows safe decoupling and allows for an unequal distribution of forces between the coupled bicycles. These needs and others which will become apparent to one skilled in the art are provided by the present invention, which is summarized and described in detail below, 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention provides a device for connecting a lead bicycle and a trailing bicycle into a tandem configuration comprising a first connector attachable to the lead bicycle, a second connector attachable to the trailing bicycle; an optional cargo rack and stowage assembly attachable to the first connector; and a telescoping interconnecting linking bar with releasable connection components on both ends of the linking bar and which includes a segment that allows a fixed amount of free longitudinal travel. One end of the linking bar assembly may be releasably connected to the trailing end of the cargo rack and stowage assembly and the other is releasably connected to the second connector. The linking bar assembly connections permit substantial rotation within the horizontal plane and more limited vertical and torsional rotation, and will release and decouple the bicycles when rotation exceeds predetermined limits, e.g., when one bicycle falls or the trailing bicycle begins to pass the lead bicycle. The telescoping linking bar assembly can be quickly retracted and completely housed inside the cargo rack and stowage assembly for stowage. The cargo rack and stowage assembly and the linking bar assembly housed therein can also be quickly removed from the first connector, which can then be used to accept a variety of accessories. The bicycle connecting device of the invention allows a lead bicycle and a trailing bicycle to be coupled together in a tandem arrangement where each bicycle has a rider and where the trailing bicycle rider may either push or be pulled. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an exemplary embodiment of the invention shown connecting lead and trailing bicycles. In this view, the invention is also shown mounted on the trailing bicycle seat post in a retracted and stowed configuration. 
         FIG. 2  is an elevation view of the embodiment shown in  FIG. 1 . 
         FIG. 3  is a perspective assembly view of an exemplary first connector used in the invention. 
         FIG. 4  is a perspective assembly view of an exemplary second connector used in the invention. 
         FIG. 5  is a perspective assembly view of an optional exemplary cargo rack and stowage assembly in accordance with one embodiment of the invention. 
         FIG. 6   a  is a cross-sectional view of an exemplary cam connecting device in an unlocked position for connecting an accessory to the first connector. 
         FIG. 6   b  is a cross-sectional view of the cam connecting device of  FIG. 6   a  in a locked position. 
         FIG. 7   a  is a perspective assembly view of an exemplary linking bar assembly of the invention. 
         FIG. 7   b  is a cross-sectional view of tube  25 . 
         FIG. 7   c  is a cross-sectional view of tube  25  at the location of out-dent  25 B. 
         FIG. 7   d  is a cross-sectional view of tube  29  at the location of indent  29 B. 
         FIG. 7   e  is a side elevational view of the threaded end of tube  20 . 
         FIG. 7   f  is a side elevational view of tube  25  at the location of out-dent  25 B. 
         FIG. 7   g  is a side elevational view of tube  29  at the location of indent  29 B. 
         FIG. 7   h  is a bottom plan view of the threaded end of tube  20 . 
         FIG. 8   a  is a cross-sectional view of a free travel segment of the linking bar assembly in a compressed configuration. 
         FIG. 8   b  is a cross-sectional view of the free travel segment of  FIG. 8   a  in an extended configuration. 
         FIG. 9  is a bottom plan view of the underside of the end cap of the linking bar assembly. 
         FIG. 10   a  is a side elevational view demonstrating lateral range of motion for the end cap of the linking bar assembly when connected to a ball stud of the second connector. 
         FIG. 10   b  is an end elevation view of the connection arrangement shown in  FIG. 10   a.    
         FIG. 10   c  is an end cross-sectional view of the connection arrangement shown in  FIGS. 10   a  and  10   b.    
         FIG. 11   a  is a cross-sectional view demonstrating vertical plane upward range of motion for the connection arrangement shown in  FIGS. 10   a ,  10   b  and  10   c.    
         FIG. 11   b  is a cross-sectional view demonstrating vertical plane downward range of motion for the connection arrangement shown in  FIGS. 10   a ,  10   b  and  10   c.    
         FIG. 12   a  is a perspective assembly view of various components of the cargo rack and stowage and linking bar assemblies. 
         FIG. 12   b  is a perspective view of the components shown in  FIG. 12   a  after assembly. 
         FIG. 12   c  is a plan view of the components shown in  FIG. 12   b  and illustrating the range of motion in the horizontal plane for this connection. 
         FIG. 13  is a side elevation view of the components of the cargo rack and stowage and the linking bar assemblies demonstrating the range of motion in the vertical plane for this connection. 
         FIG. 14  is an elevational view of the first connector, cargo rack and stowage assembly, and linking bar assembly in a retracted and stowed condition. 
         FIG. 15   a  is an elevational view of an exemplary tool kit accessory that can be connected to the first connector. 
         FIG. 15   b  is an elevational view of an exemplary bottle carrier accessory that can be connected to the first connector. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Referring to the drawings, wherein the same reference numbers refer to the same elements of the invention, there is illustrated a bicycle connecting assembly  100  for coupling a lead bicycle and a trailing bicycle in a tandem arrangement. Connecting assembly  100  includes a first connector  101 , a second connector  102 , and a telescoping linking bar assembly  103  comprising a cargo rack and stowage assembly  103 A and a telescoping coupling assembly  103 B. 
       FIGS. 1 and 2  show an exemplary preferred embodiment of connecting assembly  100  joining a lead bicycle  50  to a trailing bicycle  60 . Coupling is accomplished by the first connector  101  attaching to the lead bicycle seat post  51  on the leading end of the connecting device and by attaching trailing-bicycle telescoping linking bar  103  to the trailing bicycle head tube  62 . 
     First Connector 
     As shown in  FIG. 3 , a preferred embodiment of first connector  101  includes a clamp body  1  and a clamp face  2  which are designed and sized to encircle and clamp onto lead bicycle seat post  51 . Clamp body  1  and clamp face  2  are preferably made of a polymer such as polyamide but could also be made from other lightweight and high strength materials such as fiberglass or aluminum. Clamp body  1  and clamp face  2  have respective aligned holes  1 G and  2 A to accommodate bolts  6  and the clamp body also has nut inserts  15  fixed within clamp body  1  with the nut insert holes in alignment with the bolt holes for attachment by bolts  6 . 
     First connector  101  optionally includes a split bushing  3  which in use is positioned between lead bicycle seat post  51  and clamp body  1  and clamp face  2  in order to increase the frictional grip between the connecting parts so as to resist rotational movement about the seat post. Once in position, bolts  6  are tightened in order to provide a firm connection of first connector  101  to lead bicycle seat post  51 . Split bushing  3  is preferably made from a vinyl polymer but rubber or some similar flexible material with a high coefficient of friction could also be used. Other types of clamp connections to the bicycle seat post  51  or to the bicycle frame  50  could also be used to secure the first connector to the bicycle. 
     The trailing end of clamp body  1  has a split coupling sleeve  1 A to accommodate the insertion of the largest diameter tube  8  which optionally may be a component of cargo rack and stowage assembly  103 A. A longitudinal ridge  1 E runs the length of sleeve  1 A along the top inside wall as shown in  FIG. 3 , which accommodates a corresponding slot  8 A in tube  8  when it is inserted into clamp body  1  in order to prevent rotation between these parts and to maintain their alignment under load. 
     Sleeve  1 A is provided with a partial slot  1 B along the bottom of the horizontal shaft mount to ease insertion of tube  8  so as to accommodate slight differences in diameter that may occur in production of the parts and in consideration of the differing expansion rates at various temperatures if the parts are made of different materials. Clamp body  1  also has projecting lugs  1 C approximately midway along the length and on either side of slot  1 B. Lugs  1 C have holes  1 D through their centers and in alignment with each other to accept a standard quick connect cam and bolt assembly  4  such as those commonly used in the bicycle industry to secure a bicycle seat post to a bicycle frame. In use, cam and bolt assembly  4  is inserted through lug holes  1 D, secured with nut  5  and the lever is engaged to clamp the sides of the clamp body sleeve  1 A together to eliminate excessive gaps after tube  8  is inserted into clamp body  1 . 
     Second Connector 
       FIG. 4  illustrates an exemplary preferred embodiment of second connector  102 , which includes ball stud base  40  upon which is bolted a ball stud  21  by bolt  38  through ball stud hole  40 B. Second connector  102  attaches to the trailing bicycle head tube  62  by a bent U-bolt  41  and ball stud base  40 , which are then secured together via bolt holes  40 A with nuts  43 . A half bushing  42  is positioned between ball stud base  40  and trailing bicycle head tube  62  in order to provide a connection with increased frictional grip between the connecting parts in order to resist rotational movement about head tube  62 . Once in position, nuts  43  may be tightened to provide a firm connection of second connector  102  to trailing head tube  62 . Half bushing  42  is preferably made from the same types of material as bushing  3 . 
     U-bolt  41  is preferably slightly bent at  41 A as shown in  FIG. 4 . It should be noted that such a bent shape allows ball stud base  40  to mount to a variety of head tube frame designs where little room is available between the attachment joint of a connecting frame member and the end of the head tube. Other types of clamps may be utilized in lieu of a U-bolt style clamp, including a wire rope design with threaded attachments on the ends. U-bolt  41  is preferably made from steel or aluminum but could also be made from reinforced polymer or materials with substantial tensile strength. Ball stud base  40  is preferably made of a polymer but could also be made from other lightweight materials such as fiberglass or aluminum. 
     Cargo Rack &amp; Stowage Assembly 
       FIG. 5  illustrates an exemplary preferred embodiment of an optional cargo rack and stowage assembly  103 A. The assembly includes a tube  8  with a generally round cross-sectional profile but with a slot  8 A that runs the length of the tube. Further, tube  8  has at least one hole  8 B at the leading end that aligns with at least one hole  1 F in clamp body  1  when tube  8  is fully inserted into clamp body  1  in use. At least one arcuate snap button fastener  7  similar to those made by Valco/Valley Tool &amp; Die, Inc. of North Royalton, Ohio is preferably inserted into the leading end of tube  8  so that the snap button head  7 A projects out of hole  8 B in tube  8  and the spring flange  7 B of snap button fastener  7  align with the interior walls of tube  8 . 
     Cargo rack and stowage assembly  103 A also includes ridge connector  18  which has a hollow component  18 E with two holes  18 D to accommodate a U-shaped dual snap button  17  and a projecting platform  18 A with a semi-circular shaped ridge  18 B,  18 C on either side of the platform. With dual snap button  17  in place inside ridge connector  18  and with dual snap button heads  17 A projecting through the ridge connector holes  18 D, snap button heads  17 A can also engage the corresponding two holes  8 C at the trailing end of main tube  8 C and lock into place, connecting these components for operation. 
     Ridge connector  18  also has arcuate slotted projections  18 F extending upwards and downwards from the center line axis of the snap button holes. These projections act as an alignment guide when ridge connector  18  slides inside tube  8  during telescoping of coupling assembly  103 B, preventing rotation between U-shaped dual snap button  17  and ridge connector  18  and assisting in keeping the snap button heads  17 A in alignment with corresponding holes  8 C at the trailing end of tube  8 . Once fully extended with snap button heads  17 A projecting through holes  8 C in tube  8 , the geometry of the parts allows ridge connector  18  limited movement of approximately 60° in the vertical plane, as shown in  FIG. 13 , which allows connecting device  100  to couple bicycles of different heights. Ridge connector  18  is preferably made of a reinforced polymer such as polyamide but may also be made from other lightweight durable materials such as aluminum, fiberglass or PVC. 
     Cargo rack and stowage assembly  103 A preferably include a cargo platform  9  which mounts to tube  8  via one or more brackets  11  and end cap securing bracket  10  with bolts  12  and nuts  14 . Cargo platform  9  may be provided with slots  9 C along its edges (see  FIG. 5 ) to accept additional snap-on accessories or permit items to be tied down to the platform. 
     In use, with first connector  101  mounted on lead bicycle seat post  51 , assembly  103 A may be connected to first connector  101  by depressing the snap button head  7 A and inserting tube  8  into clamp body  1 . When tube  8  is fully inserted into the sleeve of clamp body  1 , snap button head  7 A projects out of the corresponding hole  1 F of clamp body  1  and tube  8 . Cam and bolt assembly  4  of first connector  101  may then be tightened to reduce gaps between the parts. The use of a snap button and cam and bolt assembly permits cargo rack and stowage assembly  103 A to be quickly and easily removed within seconds without tools, and at the same time allows for the attachment and detachment of a variety of other accessories to first connector  101 , such as a bottle carrier, a tool kit, a lock holder, a child seat, a pet carrier, a cargo bag, a children&#39;s bicycle training bar, etc. 
     Other quick-fastening arrangements may also be used to secure tube  8  to clamp body  1 , including, but not limited, to a V-shaped snap button in place of circular snap button  7  or a spring button fastener mounted externally on or integral with clamp body  1 . One such alternative cam connection device  71  is shown in  FIGS. 6   a  and  6   b , Cam  71  consists of a lever  71 A which is connected to a circular shaped plate  71 B with an off-center hole  71 C. Cam  71  resides in slot  1 B of clamp body  1  and is pinned or bolted with connector  72  through lug holes  1 D. With lever  71 A rotated back toward the trailing side, tube  8  is slid into sleeve  1 A of clamp body  1 . Lever  71 B is then rotated forward to the leading side as shown in  FIG. 6   b  so that one side of the cam engages a corresponding indent  8 D of main tube  8 . 
     Telescoping Coupling Assembly 
       FIGS. 7   a  through  7   h  show a preferred exemplary embodiment of telescoping coupling assembly  103 B which, in addition to tube  8 , includes four telescoping tubular segments, tube  20 , tube  25 , tube  29 , and tube  34 , each of decreasing diameter from the first to the second end of linking bar  103 , so as to allow each tube to fit inside the other and which, when extended, comprises a rigid segment of set length and, as detailed below, a segment that allows a fixed amount of free travel along the longitudinal axis. 
     Attached to the leading end of telescoping coupling assembly  103 B is tab connector  19  which has a tubular sleeve  19 F for accepting the leading end of tube  20  and to which it is secured by rivets  16 . Tab connector  19  has a longitudinal slot  19 E running along its top. Slot  19 E is sized to accept inwardly projecting slot  8 A of cargo rack and stowage assembly  103 A when telescoping coupling assembly  103 B is stowed inside cargo rack and stowage assembly  103 A. Attached to the trailing end of telescoping coupling assembly  103 B is end cap  36  which has a tubular sleeve  36 G with an internal profile similar to and designed to accept the trailing end of tube  34 . End cap  36  is secured to tube  34  by self-tapping screw  37 . 
     Tubes  25 ,  29  and  34  are respectively provided with indented grooves  25 A,  29 A and  34 A running the length of the tubes and that prevent one tube from rotating axially relative to its adjacent tube; such grooves may be in the virtually any shape that restricts axial rotation, including arcuate, oval, square, and octagonal. Tube  20  has a circular indentation  20 A shown in  FIGS. 7   e  and  7   h  which prevents tube  25  from rotating when extended inside tube  20 . The length of the telescoping sections of the tubes is preferably such that, when fully retracted, all sections nest within tube  8 , as shown in  FIG. 14 . 
     In use, tube  29  is secured to tube  25  by a V-shaped snap button connector  28  inside tube  29  with the button head  28 A projecting out of capture hole  29 D of tube  29  and which also projects out of a corresponding aligned capture hole  25 C of tube  25  when tube  29  is fully extended from tube  25 . A threaded clutch nut  27  is screwed onto corresponding threads  25 D on the trailing end of tube  25 , which secures a split bushing  26  to connect tube  29  and tube  25 . When tube  29  is fully extended and snap button head  28 A projects through the aligned hole  25 C, clutch nut  27  is tightened, forcing split bushing  26  further into the gap between tube  29  and tube  25 . This has the effect of stiffening the extended rod and reducing the amount of lateral movement between the tubes. 
     A similar arrangement secures tube  25  to tube  20 . Tube  25  is fixed to tube  20  by an arcuate snap button  24  inside tube  25  with button head  24 A projecting out of capture hole  25 E and which also projects out of the corresponding aligned capture hole  20 B when tube  25  is fully extended from tube  20 . Another threaded clutch nut  23  is screwed onto corresponding threads  20 C, which secures another split bushing  22  to connect tube  25  and tube  20 . When tube  25  is fully extended and snap button  24  projects through the aligned hole of tube  20 , clutch nut  23  is tightened, forcing split bushing  22  further into the gap between tube  25  and tube  20 . This has the same effect noted above of stiffening the extended rod and reducing the amount of lateral movement between the tubes. 
     Retraction of the telescoping tubes is accomplished by loosening the clutch nuts, pushing in the snap buttons, and sliding the smaller tube into the larger tube. Tubes  25  and  29  have respective out-dents  25 B and  29 C around the tubes to prevent them from being pulled completely out of the adjacent larger tubes when extended. Out-dent  25 B is illustrated in  FIGS. 7   c  and  7   f . Tubes  29  and  34  have respective indents  29 B and  34 B to secure respective bushings  32  and  45 . Indent  29 B is shown in  FIGS. 7   d  and  7   g . Other arrangements may also be used to secure tube  29  to tube  25  and tube  25  to tube  20 , including pin connections or twist-and-lock type connections known in the art. 
     Free Travel Component of Linking Bar 
     While tubes  20 ,  25 , and  29  lock into place when extended, one tube (for example, tube  34 ) is free to travel axially a fixed distance inside an adjacent tube (for example, tube  29 ) before reaching its travel limit in either direction. In a preferred embodiment, tube  29  may travel approximately six inches with no resistance, although other free travel distances could easily be incorporated by increasing or decreasing the various tube lengths. As shown in  FIGS. 7   a ,  8   a  and  8   b , this free travel is accomplished by incorporating a grooved bushing  45  with groove  45 B and hole  45 A into the lead end of tube  34  and securing with corresponding indentation groove  34 B in tube  34 . A corresponding indentation groove is made in tube  34  to hold grooved bushing  45  in place when under load. A similar but larger grooved bushing  32  with groove  32 B and hole  32 A is incorporated into tube  29  and held in place with corresponding groove  29 B. Rod  33  with threaded ends  33 A, springs  35  and nuts  31  is then assembled as shown in  FIGS. 8   a  and  8   b  with a nut  31  screwed onto each end of rod  33 . The finished assembly, shown in  FIGS. 8   a  and  8   b , illustrates the assembly in the compressed and extended arrangements. 
     This arrangement allows tube  34  to travel approximately six inches inside tube  29  without resistance but to encounter a spring-dampened positive stop under load at the end of the travel distance in either direction. In a preferred embodiment, the tubes are made from aluminum but could be made from other lightweight high strength materials including, but not limited to, polymer, thin gauge steel, or fiberglass. 
     In use, such an assembly dissipates the majority of de-stabilizing forces arising between the two bicycles as might be encountered on a typical ride wherein each bicycle continually moves a small distance axially back and forth relative to the other bicycle due to road surface changes and differences in pull and push forces. Without this free longitudinal travel, any axial movement of one bicycle such as that caused by a rough road or riding over an object, would be directly transmitted to the other connected bicycle, thereby causing an uncomfortable and potentially de-stabilizing event. The springs act as shock absorbers to dampen the impact should the positions of the bikes cause tube  34  to reach the limit of its travel in either direction, as can happen when one bike accelerates or brakes sharply and the other bicycle doesn&#39;t. 
     Connection of Linking Bar to Second Connector 
     Referring to  FIGS. 9 ,  10   a ,  10   b , and  10   c , end cap  36  has axial guide wings  36 B along the outside of the end cap sleeve, which act as guides to aid in keeping end cap  36  centered with respect to tube  8  during stowage. End cap  36  has pull tabs  36 F that extend downward from the bottom of end cap  36  for pulling end cap  36  out of tube  8  in preparation for linking the bikes together. End cap  36  has a projection  36 C on its underside that has an indent  36 E, shown in  FIG. 9 , which engages with spring clip  10 A of end cap securing bracket  10  (see  FIG. 5 ) of cargo rack and stowage assembly  103 A to retain the telescoping coupling assembly  103 B within tube  8  during stowage.  FIG. 14  shows spring clip  10 A engaging the indent of end cap  36  in the retracted and stowed configuration. 
     End cap  36  preferably is provided with a keyhole-shaped hole  36 D on its underside as shown in  FIG. 9 , to accept ball stud  21  of second connector  102  in a snap-on friction fit type of ball joint connection. 
       FIG. 10   c  illustrates about 75° of lateral rotation that the arrangement allows between end cap  36  and ball stud  21 ; when the limit is reached in either direction, end cap  36  and ball stud  21  separate. This limited lateral rotation of the ball joint connection allows the bicycles to remain connected during riding because the relative lateral movements of the bicycles typically do not exceed such a degree of rotation. However, should the trailing bicycle fall, the lateral rotation of the bicycles relative to each other would exceed the permitted amount of rotation and the connection will separate, thereby preventing the lead bicycle from dragging the trailing bicycle. It should also be noted that the non-rotational property of the linking bar assembly  103  facilitates this feature since otherwise, rotational forces would be transmitted to end cap  36 , causing it to separate from ball stud  21  even though the degree of lateral movement between end cap  36  and ball stud  21  has not been exceeded. 
     In a situation where the lead bicycle falls, it is desirable that linking bar assembly  103  stay connected to prevent the trailing rider from potentially running into the lead rider. The keyhole-shaped hole  36 D provides this capability. Should lead bicycle  50  fall and trailing bicycle  60  continue forward, linking bar assembly  103  would be in a state of compression and the neck of ball stud  40  will slide into the narrow slot of the keyhole  36 D of end cap  36 , capturing the ball head of ball stud  21  and preventing it from releasing from end cap  36 . The continued engagement of bicycle connecting device  100  will cause separation of the two bicycles rather than a collision, since the trailing bicycle will either be kept at a distance from the lead bicycle or the trailing bicycle will pass the lead bicycle on either side and linking bar assembly  103  will then safely release due to the design features of ridge connector  18  and tab connector  19  previously described. 
       FIGS. 11   a  and  11   b  show that about 60° of vertical rotation are allowed between end cap  36 , ball stud  21 , and ball mount  40 . This rotation capability coupled with the above-noted rotation capability of ridge connector  18  when in operational position inside tube  8  allows ample latitude for connecting bicycles of differing sizes in either the lead bicycle or trailing bicycle position. 
     Connection of Linking Bar &amp; Cargo Rack &amp; Stowage Assembly 
     Referring to  FIGS. 12   a ,  12   b , and  12   c , tab connector  19  has lower and upper projections  19 B and  19 D, these projections having respective cylindrical tabs  19 A and  19 C. Tabs  19 A and  19 C encircle and capture the semi-circular shaped rims  18 B and  18 C of ridge connector  18  of cargo rack and stowage assembly  103 A. The geometry of ridge connector  18  and tab connector  19  when engaged allow approximately 180° of lateral rotation (90° on either side of the axial centerline of the parts) yet remain connected. When the 90° limit is exceeded on either side, tab connector  19  and the attached tubing assembly will disconnect from ridge connector  18 . 
     In use, this has the effect of decoupling the bicycles and preventing an unsafe situation when the trailing bicycle begins to pass the lead bicycle or the direction of travel of the two bicycles becomes sufficiently divergent, as can occur during tight turns or when the trailing rider fails to otherwise follow the lead rider. The geometry and size of the semi-circular rim on ridge connector  18  may easily be changed to increase or decrease the limit of rotation at which separation takes place. In a preferred embodiment, tab connector  19  is typically made of reinforced polymer, but may also be made from other lightweight durable materials such as aluminum or fiberglass. Other connection configurations may also be used to produce similar levels of horizontal rotation and release and still remain within the scope of the invention. 
     Stowage of Linking Bar 
       FIG. 14  shows bicycle connecting assembly  100  in a retracted and stowed arrangement. This is desirable when two riders wish to ride independently and is accomplished with no tools and typically in less than a minute. To convert from a bicycle-linking arrangement to a stowed arrangement, clutch nuts  23  and  27  are loosened approximately one half turn. End cap  36  is then lifted off of ball joint  21 . Then snap button head  24 A is depressed and tube  25  is slid into tube  20 . Next, snap button head  28 A is depressed and tube  29  is slid into tube  25 . The snap button heads  17 A are then depressed and tube  20  is slid into tube  8 . Finally, end cap  36  is pushed in until spring latch  10 A of end cap securing bracket  10  engages indent  36 E on the underside projection  36 C of end cap  36 , thereby securing the entire telescoping coupling assembly  103 B within cargo rack and stowage assembly  103 A. 
       FIGS. 15   a  and  15   b  respectively illustrate a tool kit accessory  73  and a bottle carrier  74  accessory that could replace cargo rack and stowage assembly  103 A and be connected to first connector  101  during a given ride should an individual rider desire to take along such accessories instead of the linking bar assembly. 
     The terms and expressions which have been employed in the foregoing specification are used therein as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding equivalents of the features shown and described or portions thereof, it being recognized that the scope of the invention is defined and limited only by the claims which follow.