Abstract:
A stroller track system is used to facilitate the transporting of a stroller up and down stairs. The stroller track system includes a left tread assembly and a right tread assembly. The left tread assembly and the right tread assembly are used to engage multiple stairs while traversing a set of stairs. This allows the stroller to glide smoothly up or down the stairs. The left tread assembly and the right tread assembly each include a first track and a first stroller-attaching mount. The first track has a greater surface area than a normal wheel, allowing the first track to span a larger section of a staircase. The first stroller-attaching mount is used to attach the first track to a stroller. In alternative versions of the stroller track system, the left tread assembly and the right tread assembly may include additional tracks to further stabilize the stroller.

Description:
The current application claims a priority to the U.S. Provisional Patent application Ser. No. 62/155,358 filed on Apr. 30, 2015. The current application is filed on May 2, 2016 while Apr. 30, 2016 was on a weekend. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to track systems used to facilitate the moving of strollers up and down stairs. More specifically, the present invention is a stroller track system which may be attached to the underside of a stroller and used to engage multiple stairs in a staircase in order to move up and down stairs smoothly. 
     BACKGROUND OF THE INVENTION 
     Strollers have become essential for transporting young children or people with disabilities. There are a variety of stroller designs available today, however none solve the common challenge of going up and down stairs. Many individuals that have used a stroller will say that going up and down stairs is a challenging and inconvenient task. In most cases, an individual must carry the stroller up and down stairs, typically requiring the help of another person. Alternatively, the user may lift the stroller one stair at a time in order to traverse a set of stairs. Both approaches can be tiring and cumbersome. 
     Accordingly, the present invention aims to solve the problem of transporting strollers up and down stairs. The present invention is a stroller track system that can be attached or connected to the underside of a stroller. The stroller track system uses a left tread assembly and a right tread assembly which both remain in a folded configuration under the stroller during normal use. When a user needs to traverse up or down a set of stairs, the user may unfold the left tread assembly and the right tread assembly manually, or at the push of a button. By moving the left tread assembly and the right tread assembly into an unfolded configuration, the left tread assembly and the right tread assembly may be engaged with multiple stairs, allowing the stroller to easily glide up or down the staircase. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front left perspective view of a first embodiment of the present invention, wherein the first track is connected to the first stroller-attaching mount and the second stroller-attaching mount in the first embodiment. 
         FIG. 2  is a front right perspective view of the first embodiment of the present invention. 
         FIG. 3A  is a schematic view showing a preferred embodiment of the first track. 
         FIG. 3B  is a schematic view showing an alternative embodiment of the first track. 
         FIG. 4  is a front left perspective view of a second embodiment of the present invention in the folded configuration, wherein the second embodiment comprises the second track and the track-securing bracket, and wherein the track-securing bracket is free to move. 
         FIG. 5  is a front left perspective view of the second embodiment of the present invention in an unfolded configuration, wherein track securing bracket is attached to the front wheel assembly in the unfolded configuration. 
         FIG. 6  is a rear left perspective view of the second embodiment of the present invention in the unfolded configuration. 
         FIG. 7  is a left side view of the second embodiment of the present invention in the unfolded configuration. 
         FIG. 8  is a left side view of the second embodiment of the present invention with the seat adjusted for traversing stairs. 
         FIG. 9  is a front left perspective view of a third embodiment of the present invention, wherein the second track is slidably engaged with the first track in the third embodiment. 
         FIG. 10  is a front left perspective view of a fourth embodiment of the present invention, wherein the first track is pivotally connected to the first stroller-attaching mount and the second track is slidably engaged with the second stroller-attaching mount in the fourth embodiment. 
         FIG. 11  is a front left perspective view of a fifth embodiment of the present invention, wherein the first track is pivotally connected to the first stroller-attaching mount and the second track is pivotally connected to the second stroller-attaching mount in the fifth embodiment. 
         FIG. 12  is a front left perspective view of the fifth embodiment using a supplementary track. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     All illustrations of the drawings are for the purpose of describing selected versions of the present invention and are not intended to limit the scope of the present invention. 
     With reference to  FIGS. 1-2 , and  FIGS. 3A-3B , the present invention is a stroller track system which is used to assist a user in navigating a stroller  17  up and down stairs. The present invention comprises a left tread assembly  1  and a right tread assembly  2 . The left tread assembly  1  and the right tread assembly  2  are used to provide a continuous contact surface for a stroller  17 , distributing the weight of the stroller  17  across the edges of multiple stairs in a staircase. This allows the user to push the stroller  17  up the stairs instead of lifting the stroller  17  up and over each step. The left tread assembly  1  and the right tread assembly  2  each comprise a first track  3  and a first stroller-attaching mount  10 . The first track  3  forms a continuous band which may be lowered to engage multiple stairs at a time. By engaging multiple stairs at a time, the first track allows the stroller to move smoothly up or down a set of stairs. The first track  3  comprises a belt  4 , a proximal wheel  5 , a distal wheel  6 , and a wheel mounting bracket  7 . The wheel mounting bracket  7  is used to stabilize the proximal wheel  5  and the distal wheel  6 . The proximal wheel  5  and the distal wheel  6  are rotatably connected to the wheel mounting bracket  7 . The proximal wheel  5  and the distal wheel  6  are positioned opposite to each other along the wheel mounting bracket  7 . This arrangement allows the belt  4  to be perimetrically positioned about the proximal wheel  5 , the wheel mounting bracket  7 , and the distal wheel  6 . This creates a continuous surface upon which the stroller  17  can roll. The first stroller-attaching mount  10  is bistably connected to the first track  3  and is used to mount the first track  3  to the stroller  17 . This allows the first track to be engaged or disengaged with the floor or a set of stairs. 
     In the preferred embodiment of the first track  3 , shown in  FIG. 3A , the wheel mounting bracket  7  is a platform  8 . The platform  8  helps to support the belt  4  and prevents the belt  4  from flexing or deforming excessively during use. The belt  4  is slidably engaged with the platform  8  so that the belt  4  is free to rotate about the proximal wheel  5 , the platform  8 , and the distal wheel  6 . The preferred embodiment of the first track  3  may also be used for additional tracks. 
     In an alternative embodiment of the first track  3 , shown in  FIG. 3B , the first track  3  further comprises at least one intermediate wheel  9 . The at least one intermediate wheel  9  is rotatably connected to the wheel mounting bracket  7  and is linearly distributed between the proximal wheel  5  and the distal wheel  6 . In this embodiment, the belt  4  is tangentially positioned about the at least one intermediate wheel  9  so that the proximal wheel  5 , the distal wheel  6 , and the at least one intermediate wheel  9  may all be used to support the belt  4 . This ensures that the belt  4  create an even surface for rolling up and down stairs. 
     In a first embodiment of the present invention, shown in  FIGS. 1-2 , the left tread assembly  1  and the right tread assembly  2  each further comprise a second stroller-attaching mount  11 . The second stroller-attaching mount  11  is designed to give added support to the first track  3 . The first stroller-attaching mount  10  is terminally positioned along the first track  3 . The second stroller-attaching mount  11  is connected adjacent to the first track  3 , opposite to the first stroller-attaching mount  10 . It is preferred that, the first stroller-attaching mount  10  and the second stroller-attaching mount  11  are height-adjustable pistons which may be used to move the first track  3  towards or away from the floor or the stairs upon which the stroller  17  is rolling. 
     The present invention further comprises a stroller  17  which comprises a frame  18 , a front wheel assembly  19 , and a rear wheel assembly  20 . Similar to a typical stroller, the front wheel assembly  19  and the rear wheel assembly  20  allow the stroller  17  to roll across relatively flat surfaces. The front wheel assembly  19  is mounted to the frame  18 , and the rear wheel assembly  20  is mounted to the frame  18 , opposite to the front wheel assembly  19 . The left tread assembly  1  and the right tread assembly  2  are mounted opposite to each other across the frame  18  to equally distribute the weight of the stroller  17 . The first stroller-attaching mount  10  is connected to the frame  18 , adjacent to the rear wheel assembly  20 . The second stroller-attaching mount  11  is connected to the frame  18 , adjacent to the front wheel assembly  19 . As mentioned, in the first embodiment of the present invention, the first stroller-attaching mount  10  and the second stroller-attaching mount  11  are height adjusting pistons. This allows the first stroller-attaching mount  10  and the second stroller-attaching mount  11  to lift the frame  18  by pushing the first track  3  towards the ground or stairs. When folding the stroller  17  for storage or transportation, the stroller-attaching mount  11  can be detached from the frame  18  to allow frame  18  to collapse into a compact space saving configuration. 
     In a second, and preferred, embodiment, of the present invention, the left tread assembly  1  and the right tread assembly  2  each further comprise a second track  12  and a track-securing bracket  13 . In reference to  FIGS. 4-6 , the second track  12  is used to further increase the effective contact surface length of the stroller  17 , beyond what is capable using only the first track  3 . Combined, the first track  3  and the second track  12  are used to span the length of at least three stair edges. This ensures that when the user is pushing the stroller  17  up a set of stairs, a minimum of two stairs are engaged at any given time. The first track  3  is pivotally mounted to the first stroller-attaching mount  10 . The first stroller-attaching mount  10  is pivotally connected to the frame  18 , adjacent to the rear wheel assembly  20 . This arrangement allows the first track  3  to be pivoted until the first track  3  is engaged with the ground or a set of stairs. The second track  12  is pivotally connected to the first track  3 , opposite to the stroller-attaching mount. This allows the second track  12  to pivot between a folded configuration and an unfolded configuration. By unfolding the second track  12 , the first track  3  and the second track  12  may be simultaneously engaged with the ground or a set of stairs. The track-securing bracket  13  is connected to the second track  12 , opposite to the first track  3 . The track-securing bracket  13  is used to stabilize the second track  12 . To do this, the track-securing bracket  13  is removably attached to the front wheel assembly  19 . 
     Also in the second embodiment of the present invention, the left tread assembly  1  and the right tread assembly  2  each comprise a track adjustment lever  14 . The track adjustment lever  14  provides leverage for the user to fold and unfold the first track  3  and the second track  12 . The track adjustment lever  14  is pivotally connected to the first track  3  and the second track  12 . The track adjustment lever  14  is also slidably and pivotally engaged with the frame  18 . This arrangement allows the user to push and rotate the track adjustment lever  14  to simultaneously unfold the first track  3  and the second track  12  until both are engaged with the ground or stairs. Alternatively, the left tread assembly  1  and the right tread assembly  2  may be motorized to transition in-between the folded configuration and the unfolded configuration. To do so, a track-engaging motor may be mechanically integrated into the pivotal connection between the first track  3  and the second track  12 . Though this represents the preferred method, additional components may be mechanically integrated into the left tread assembly  1  and the right tread assembly  2 . As a result, user exertion is minimized during the process of transitioning the left tread assembly  1  and the right tread assembly  2  between the folded configuration and the unfolded configuration. Further, the left tread assembly  1  and the right tread assembly  2  may be motorized to propel the stroller  17 . By motorizing the left tread assembly  1  and the right tread assembly  2  in this way, the user may be aided in pushing the stroller  17  up a set of stairs. To motorize the left tread assembly  1  and the right tread assembly  2  for the purpose of propulsion, at least one propulsion motor is mechanically integrated into the first track  3 . The propulsion motor may either be engaged with the proximal wheel  5  or the distal wheel  6 . Alternatively, the at least one propulsion motor may be mechanically integrated into the second track  12 . 
     In a third embodiment of the present invention, shown in  FIG. 9 , the left tread assembly  1  and the right tread assembly  2  each further comprise a second track  12  and a second stroller-attaching mount  11 . The second track  12  is used to further increase the effective surface length of the stroller  17 , beyond what is capable using only the first track  3 . The first stroller-attaching mount  10  is terminally positioned along the first track  3 . The second stroller-attaching mount  11  is connected adjacent to the first track  3 , offset from the first stroller-attaching mount  10 . Similar to the preferred embodiment of the present invention, the first stroller-attaching mount  10  and the second stroller-attaching mount  11  are height-adjustable pistons. The first stroller-attaching mount  10  and the second stroller-attaching mount  11  are used to move the first track  3  towards or away from the floor or the stairs upon which the stroller  17  is rolling. The first stroller-attaching mount  10  is connected to the frame  18 , adjacent to the rear wheel assembly  20 . The second stroller-attaching mount  11  is connected to the frame  18 , adjacent to the front wheel assembly  19 . By offsetting the first stroller-attaching mount  10  and the second stroller-attaching mount  11 , the weight of the stroller  17  may be equally distributed. The third embodiment differs from the preferred embodiment because the second track  12  is slidably engaged with the first track  3 . This allows the second track  12  to extend outward from the first track  3  so that more stairs may be engaged at a time. This increases the stability of the stroller  17  when rolling on stairs. 
     In a fourth embodiment of the present invention and a fifth embodiment of the present invention, the left tread assembly  1  and the right tread assembly  2  each further comprise a second track  12 , a second stroller-attaching mount  11 , and a height adjustment bracket  15 . In reference to  FIGS. 10-11 , the height adjustment bracket  15  is used to stabilize the connection between the first track  3  and the second track  12 . In both the fourth embodiment of the present invention and the fifth embodiment of the present invention, the first stroller-attaching mount  10  is pivotally connected to the first track  3 , and the second stroller-attaching mount  11  is bistably connected to the second track  12 . This arrangement allows the second track  12  to be moved towards or away from the floor or the stairs in which the user wishes to traverse. The first stroller-attaching mount  10  and the second stroller-attaching mount  11  are used to stabilize the first track  3  and the second track  12 . The second track  12  is pivotally connected to the first track  3 , opposite to the first stroller-attaching mount  10 . This allows the second track  12  to be pivoted between the folded and the unfolded configuration. The first track  3  is slidably and rotatably engaged with the height adjustment bracket  15 , opposite to the first stroller-attaching mount  10 . This helps to guide the first track  3  and the second track  12  in between the folded configuration and unfolded configuration. Further, the connection between the first track  3  and the height adjustment bracket  15  helps to stabilize both the first track  3  and the second track  12  in the unfolded configuration. 
     In the fourth embodiment of the present invention, shown in  FIG. 10 , the first stroller-attaching mount  10  is pivotally connected to the frame  18 , adjacent to the rear wheel assembly  20 . The second stroller-attaching mount  11  is slidably engaged to the frame  18 , adjacent to the front wheel assembly  19 . This arrangement provides a simple means of transitioning the first track  3  and the second track  12  in between the folded configuration and the unfolded configuration. The height adjustment bracket  15  is mounted to the frame  18 , in between the front wheel assembly  19  and the rear wheel assembly  20 . This arrangement also helps to evenly distribute the weight of the stroller  17  onto the first track  3  and the second track  12 . 
     In the fifth embodiment of the present invention, shown in  FIG. 11 , the first stroller-attaching mount  10  is pivotally connected to the frame  18 , adjacent to the rear wheel assembly  20 . Similarly, the second stroller-attaching mount  11  is pivotally engaged to the frame  18 , adjacent to the front wheel assembly  19 . This arrangement allows the first track  3  and the second track  12  to unfold symmetrically. This arrangement also allows the act of extending the stroller  17  to be used as a means of transitioning the first track  3  and the second track  12  into the unfolded configuration. Similar to the fourth embodiment of the present invention, the height adjustment bracket  15  is mounted to the frame  18 , in between the front wheel assembly  19  and the rear wheel assembly  20 . This arrangement equally helps to evenly distribute the weight of the stroller  17  onto the first track  3  and the second track  12 . 
     In each embodiment of the present invention, the stroller  17  further comprises a seat  21 . In reference to  FIGS. 7-8 , the seat  21  is used to hold one or more small children for transport. The seat  21  is adjustably mounted to the frame  18  so that the orientation of the seat  21  may be selectively configured to account for the orientation of the first tread assembly and the second tread assembly. This is done to ensure the comfort of the child or children held in the seat  21 . Further, this arrangement helps to prevent children from falling out of the seat  21  while the stroller  17  is traversing down a set of stairs. 
     Though the aforementioned embodiments have limited the left tread assembly  1  and the right tread assembly  2  to the first track  3  and, in some cases, the second track  12 , it is to be noted that additional tracks may be added. In reference to  FIG. 12 , the left tread assembly  1  and the right tread assembly  2  may each comprise a second track  12  and at least one supplemental track  16 . In this case, the second track  12  is pivotally connected to the first track  3 . The at least one supplemental track  16  is pivotally connected to the second track  12 , opposite to the first track  3 . This allows each of the tracks to be positioned in the folded configuration. When moved into the unfolded configuration, the first track  3 , the second track  12 , and the at least one supplemental track  16  are aligned end-to-end. It is to be understood that any number of supplemental tracks  16  may be added. 
     Although the invention has been explained in relation to its preferred embodiments, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed.