Abstract:
An infant stroller having a fold latch mechanism to lock the stroller in the unfolded or deployed configuration. The side of the stroller contains a latchkey piece having a pocket-like recess that engages a latchpin on the stroller&#39;s front leg. When the latchkey is in the locked position, the front legs are held in place, locking the stroller in the unfolded or deployed configuration. When the latchkey is disengaged from the latchpin on the front leg, the front leg can be rotated to allow the stroller to be folded for storage or transport. The stroller also has a latching mechanism for locking the tray unit in place during normal use. The tray unit becomes unlocked and can be tucked away during the folding process.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     This invention relates to an infant stroller, and in particular to a fold and latch mechanism for an infant stroller.  
         [0002]     The prior art includes infant strollers capable of being folded, as well as strollers with trays capable of being folded. Although some of the strollers seen in the prior art include latching and locking mechanisms that interact with the stroller legs and frame components to lock the stroller in place when unfolded, none of the prior art describes latching and locking mechanisms of the type described and claimed herein.  
       SUMMARY  
       [0003]     The present invention is directed generally to an infant stroller having a fold latch mechanism to lock the stroller in the unfolded or deployed configuration. The stroller also has a latching mechanism for locking the tray unit in place during normal use. The tray unit becomes unlocked and can be tucked away during the folding process.  
         [0004]     Accordingly, it is a first aspect of the present invention to provide an infant stroller comprising: at least one side member; at least one front leg joined to the side member and capable of rotating with respect to the side member, the front leg having a nub capable of engaging a latchkey for preventing rotation of the front leg with respect to the side member; at least one rear leg joined to the side member and capable of rotating with respect to the side member; at least one handle bar joined to the side member; a locking mechanism for preventing rotation of the front leg with respect to the side member, the locking mechanism comprising a latchkey pivotally attached to the side member, the latchkey having a recess capable of engaging the nub on the front leg, and the latchkey capable of rotating with respect to the side member; and at least one frame member pivotally joining the front leg to the rear leg and capable of preventing the rear leg from pivoting away from the front leg when the front leg is locked by the locking mechanism; wherein the front leg is locked in a fixed position with respect to the side member when the latchkey is positioned such that its recess is engaged with the nub on the front leg; and wherein the front leg is unlocked, thereby capable of rotating with respect to the side member, when the latchkey is positioned such that its recess is disengaged from the nub on the front leg. In a detailed embodiment, the stroller has a biasing element for biasing the latchkey to the locked position. The biasing element, which can be positioned on the end of the latchkey, can be a spring that is received on one end by a nub on the end of the latchkey and is received on the opposite end by a nub on the side member.  
         [0005]     In an alternative detailed embodiment of the first aspect of the present invention, the stroller can be folded, when the latchkey is positioned such that its recess is disengaged from the nub on the front leg, by rotating the front leg and rear leg such that the side member becomes approximately parallel to the front leg and rear leg. In another alternative detailed embodiment, the latchkey includes a wheel portion and an arm portion; and the recess is located on the arm portion. In yet another alternative detailed embodiment, the stroller has at least one cable joined to the latchkey and capable of manipulating the latchkey between engaged and disengaged positions. In a more detailed embodiment, upon application of a force to the cable, the latchkey is rotated with respect to the side member such that the recess is disengaged from the nub on the front leg. In an alternative more detailed embodiment, the stroller includes a latch release control joined to the cable and capable of being depressed by a user. In an even more detailed embodiment, the stroller can include a handle assembly joined to the top of the handle bar, where the latch release control is joined to the handle assembly, and where the cable is located in the interior of the handle bar.  
         [0006]     It is a second aspect of the present invention to provide an infant stroller comprising: at least one side member; at least one front leg joined to the side member and capable of rotating with respect to the side member; a tray unit including a tray and at least one tray arm, the tray arm joined to the side member and capable of rotating with respect to the side member, the tray arm having a graduated recess on its side face having a deep end and a shallow end, the shallow end being flush with the side face of the tray arm; and a tray locking mechanism for preventing rotation of the tray arm with respect to the side member, the tray locking mechanism comprising: a frame; a latchpin capable of engaging the recess in the tray arm; a carrier for holding the latchpin in place and capable of sliding within the frame; a first spring to provide restoring force to the latchpin when depressed; and a second spring to provide restoring force to the carrier; wherein the latchpin is engaged with the deep end of the recess on the tray arm when the front leg is in an unfolded position with respect to the side member, thereby locking the tray arm and the tray in a fixed position with respect to the side member; and wherein the latchpin is engaged with the shallow end of the recess on the tray arm when the front leg is in a folded position with respect to the side member, thereby allowing the tray arm and the tray to rotate with respect to the side member. In a detailed embodiment, the carrier of the tray locking mechanism unit is positioned such that the latchpin is engaged with the deep end of the recess on the tray arm when the front leg is in an unfolded position with respect to the side member, thereby locking the tray arm and the tray in a fixed position with respect to the side member and, upon rotation of the front leg to a folded position, the carrier of the tray locking mechanism unit is positioned such that the latchpin is engaged with the shallow end of the recess on the tray arm, thereby allowing the tray arm and the tray to rotate with respect to the side member. The second aspect of the present invention can be practiced with any of the features or embodiments described above with respect to the first aspect of the present invention. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]      FIG. 1  shows a perspective view of the infant stroller according to an embodiment of the present invention.  
         [0008]      FIGS. 2 and 3  are cutaway side views of the infant stroller according to an embodiment of the present invention, showing the connection of the various components to the side member. The stroller is in the unfolded or deployed configuration in this view.  
         [0009]      FIG. 4  is a closeup view showing the latchkey piece and the cable&#39;s connection to the latchkey piece.  
         [0010]      FIG. 5  is cutaway side view of the infant stroller according to an embodiment of the present invention, showing the connection of the various components to the side member. The stroller is in a partially folded configuration in this view.  
         [0011]      FIG. 6  is a side view of the infant stroller according to an embodiment of the present invention, showing the stroller in a completely folded configuration.  
         [0012]      FIG. 7  shows the tray unit of the infant stroller according to an embodiment of the present invention.  
         [0013]      FIG. 8  is a cutaway perspective view showing the various components of the latch release mechanism and the tray lock mechanism of the infant stroller according to an embodiment of the present invention. The stroller is in the unfolded or deployed configuration in this view.  
         [0014]      FIG. 9  shows the tray lock mechanism of the infant stroller according to an embodiment of the present invention.  
         [0015]      FIG. 10  is a cutaway perspective view showing the various components of the latch release mechanism and the tray lock mechanism of the infant stroller according to an embodiment of the present invention. The stroller is in a partially folded configuration in this view.  
     
    
     DETAILED DESCRIPTION  
       [0016]      FIG. 1  shows a perspective view of the infant stroller  10  according to an embodiment of the present invention. The stroller  10  is generally formed from a frame including rear legs  12 , front legs  14 , and handle bars  16 . One each of the rear legs, front legs, and handle bars is pivotally joined to a side member  18  to form each of the left and right sides of the frame. The side member  18  generally has two parallel side panels joined by a closed upper edge, resulting in a U-shaped cross-section. The legs and handle bars extend into the resulting cavity enclosed between the two parallel faces of the side member  18 , and various components described below are housed in this cavity and fastened to one or both of the side panels. Accordingly, the right and left sides of the stroller each include one rear leg  12 , one front leg  14 , one handle bar  16 , and one side member  18 . The right and left sides of the frame are joined by several cross braces, including the front base panel  23 , the two rods  24 , the undercarriage  26 , and the handle assembly  28 . In addition to the aforementioned frame components, the stroller includes a tray unit  20  that is joined to the two side members  18 .  
         [0017]      FIGS. 2 and 3  are cutaway side views, which show the connection of the various components to the side member  18 . The rear leg  12  is connected to the side member  18  at point  30 , which allows free rotation. The handle bar  16  is connected to the side member  18  at points  32 . The front leg  14  is connected to the side member  18  through the leg cap  33  at point  34 , which allows rotation. The ability of the front leg  14  to rotate about its attachment point  34  is governed by latchkey  36 , which is pivotally connected to the side member  18  at point  38 .  
         [0018]     The attachment and rotation of the front leg  14  can also be seen in the perspective views of  FIGS. 8 and 10 . The front leg  14  has a leg cap  33  on its top end, and the front leg  14  is joined to the side member  18  through a cylindrical sleeve  35  located on the edge of the leg cap  33 . The resulting off-center point of rotation for the front leg  14  allows a nub  68  on the leg cap  33  to operate the tray lock mechanism  54  during rotation of the front leg, as explained below.  
         [0019]      FIG. 4  shows a closeup view of the latchkey  36 , which includes a wheel portion  37  and an arm portion  40  containing a recess  42  for receiving nub  44  on the leg cap  33 . A cable  46  is connected to the latchkey through an opening  70  and serves to apply force tangential to the wheel portion  37  in order to rotate the latchkey, as explained below. The cable  46  is secured by a bead  72 , which fits into one end of a cylindrical sleeve  74 . The cylindrical sleeve  74  fits into a bushing  76 , which fits into an opening  70  in the latchkey  36 . The attachment fairing  78  provides an attachment point for spring  45 , which provides restoring force to hold the latchkey in a locked position, as explained below.  
         [0020]     In the configuration depicted in  FIGS. 2 and 3 , the latchkey  36  is positioned such that its recess  42  is engaged with nub  44  on the leg cap  33 , thus preventing rotation of the front leg  14  about its attachment point  34 . Because the front legs  14  are joined to the rear legs  12  by undercarriage  26 , the rear leg  12  is also prevented from rotating about its attachment point  30  in this configuration. Thus, when the latchkey  36  is positioned as shown in  FIGS. 2 and 3 , the stroller is locked in the unfolded or deployed configuration. Spring  45  provides restoring force to the latchkey  36 , biasing it in the locked position shown in  FIGS. 2 and 3  to prevent the stroller from folding absent intention of the user.  
         [0021]     The fold process is initiated by rotating latchkey  36  about its attachment point  38  so that its recess  42  is no longer engaged with the nub  44 , as shown in  FIG. 5 . This rotation of the latchkey  36  can be accomplished by applying force to a cable  46  that can be routed through the handle bars  16  and connected to a latch release located in the handle assembly  28 . The cable applies an upward force to the latchkey tangential to the wheel portion  37 , thus overcoming the downward restoring force exerted by the spring  45 , and the latchkey  36  can rotate in a clockwise direction. When the recess  42  is disengaged from the nub  44 , the front leg  14  is able to rotate about its attachment point  34 .  
         [0022]      FIG. 5  shows the stroller after the folding process has been commenced and the legs have begun to rotate. The front leg  14  begins to fold back (counterclockwise when viewed from the stroller&#39;s left side, as in  FIG. 5 ). The rear leg  12 , which is connected to the front leg  14  by the undercarriage  26 , begins to fold back as well. As the folding process continues, the front legs  14  and rear legs  12  continue to fold back, approaching a parallel alignment.  FIG. 6  shows the stroller after the folding process has been completed, with the front legs  14  and rear legs  12  nearly parallel.  
         [0023]     In addition to folding the legs to a nearly parallel configuration, the fold process also allows the tray unit  20  to fold into the approximate plane of the folded legs. The tray unit  20  is shown in  FIG. 7  and generally consists of the tray  21  and two tray arms  22  that connect the tray to the two side members  18 . Each tray arm  21  has a recess  48  on its side. The recess  48  has a deep portion  50  and a narrow portion  52  for engaging a latchpin  56  on the tray lock mechanism  54 , as explained below.  
         [0024]      FIG. 8  is a perspective view showing the interaction of the tray arm  22  with the side member  18 . The tray arm  22  on each side is pivotally connected to the side member  18  at the same point  34  where the front leg  14  is connected. Inside the side member  18  is located a tray lock mechanism  54  that is shown in more detail in  FIG. 9 . The tray lock mechanism  54  includes the latchpin  56  that engages the aforementioned recess  48  in the tray arm  22 . The latchpin  56  is held in place by a carrier  58  that can slide within a frame  60 . A first spring  62  provides restoring force to the latchpin  56  when depressed, and a second spring  64  provides restoring force to the carrier  58  in the direction of the closed end  66  of the frame  60 .  
         [0025]     Returning to  FIG. 8 , which shows the stroller in the unfolded or deployed configuration, the latchpin  56  is engaged with the deep portion  50  of the recess  48  in the tray arm  22 . In this configuration, the latchpin  56  prevents the tray arm  22 , and hence the tray assembly  20 , from rotating.  
         [0026]     When the folding process has commenced, the carrier  58  slides within the frame  60  to the configuration shown in  FIG. 10 , carrying the latchpin  56  with it. The carrier  58 , including the latchpin  56 , moves so that the latchpin  56  is aligned with the shallow portion  52  of the recess  48  in the tray arm  22 . This movement of the carrier  58  is initiated by the rotation of the front leg  14 , which rotates the leg cap  33  on the front leg  14  so that the nub  68  on the leg cap  33  is no longer in contact with the carrier  58 . As a result of this disengagement of the nub  68  from the carrier  58 , the second spring  64  pushes the carrier  58  to the closed end  66  of the frame  60 , thus moving the latchpin  56  so that it is aligned with the shallow portion  52  of the recess  48  on the tray arm  22 . Because the shallow portion  52  is flush with the surface of the tray arm  22 , the tip of the latchpin  56  is now flush with the surface of the tray arm  22 ; the latchpin  22  is no longer engaged with the recess  48  in a way that would prevent rotation of the tray arm  22 . The tray arm  22  is now free to rotate with respect to the side member  18 , as shown in  FIG. 10 . During the folding process, the user can manually rotate the tray unit  20  to tuck it between the side members  18  for transportation or storage.  
         [0027]     Having described the invention with reference to embodiments, it is to be understood that the invention is defined by the claims and it not intended that any limitations or elements describing the embodiments set forth herein are to be incorporated into the meanings of the claims unless such limitations or elements are explicitly listed in the claims. Likewise, it is to be understood that it is not necessary to meet any or all of the identified advantages or objects of the invention disclosed herein in order to fall within the scope of any claims, since the invention is defined by the claims and since inherent and/or unforeseen advantages of the present invention may exist even though they may not have been explicitly discussed herein.