Abstract:
A portable stroller that includes a collapsible frame that has two Y-shaped support units and a plurality of links which collapsibly mount a seat section thereon.

Description:
TECHNICAL FIELD OF THE INVENTION 
     The present invention relates generally to land vehicles, and more particularly to a collapsible stroller for transporting a child. 
     BACKGROUND OF THE INVENTION 
     Ever since babies have been born, parents have looked for a convenient way of traveling with their children. From slings to pouches, babies have been transported in a number of ways. Today we do it a bit differently, but how did we get our modern day strollers? Where did it all start? 
     The idea of a baby stroller first came into being with a man named William Kent. He was a garden architect in England who had become very well known for his work. In 1733, the Duke of Devonshire asked Kent to build a means of transportation that would amuse his children. Kent obliged by constructing a shell shaped basket on wheels that the children could sit in. This was richly decorated and meant to be pulled by a goat or small pony. Kent&#39;s idea caught on and soon other royal families owned similar contraptions. 
     In 1840, the baby carriage became extremely popular. Queen Victoria bought three carriages from Hitchings Baby Store. Though these models were very tall and relatively unsafe, but they were in fashion. If you wanted to be part of high society, you had to own a baby carriage. 
     The carriages of those days were much different than today. They were built of wood or wicker and held together by expensive brass joints. These were very fancy and became heavily ornamented works of art. Models were also named after royalty. Princess and Duchess were popular names, as well as Balmoral and Windsor. 
     Up until this time, baby carriages had always been pulled by a pony or dog, but in 1848, a new design appeared. American Charles Burton decided to put handles on carriages so that the parents could actually use the vehicle as a means of transporting their children. This idea was not accepted in America, so Burton moved to England and was hired by individuals such as Queen Victoria, Queen Isabella, and the Pasha of Egypt. 
     In June of 1889, a new carriage design came on to the public scene. William Richardson patented his idea of the first reversible stroller. The bassinet was designed so it could face out or in towards the parent. He also made structural changes to the carriage. Until then, the axils did not allow each wheel to move separately. 
     Richardson&#39;s design allowed this, which increased maneuverability of the carriages. As the 1920s, began, World War I was coming to an end. Modern baby carriages were now available to all families. They were also becoming safer, as new features like larger wheels, brakes, deeper prams, and lower, sturdier frames began to appear. By 1950, these carriages were a must have for all families. 
     In 1965, Owen Maclaren, an aeronautical engineer, listened to his daughter complain about traveling from England to America with her heavy pram. Maclaren knew that she needed something with a light frame that could fold up compactly. Using his knowledge of airplanes, Maclaren built an aluminum frame and created the first true umbrella stroller. This design took off and soon strollers were easier to transport and used everywhere. 
     By 1980, another huge step in stroller design was taken. Phil Baechler decided he wanted to do some running and take his son with him. He saw that the stroller he owned would never hold up to this activity, so he took the wheels off his bike and tried it out. After several attempts he finally worked out the Baby Jogger design. 
     Since the 1980s, the stroller industry has grown leaps and bounds. New features, safer construction, and more accessories have opened up a whole new world to parents of infants and toddlers. 
     Collapsible strollers for babies and small children are well known and widely used. Known collapsible strollers, however, fold into a bulky and outsize configuration. Some provide for folding and carrying on the back of an adult, however they fold into a bulky, inconvenient collapsed configuration. Some collapsible strollers are inherently uncomfortable for the child. Although it is known to provide a folding configuration which may be placed in a carrying case and carried by a handle by an adult, the configuration remains bulky and relatively difficult to carry, handle, and store. It would be desirable to provide a collapsible stroller for a child which is inherently comfortable for the child. It would further be desirable if such a collapsible stroller would assume a generally cylindrical collapsed configuration for fitting in a soft, duffle-type bag having straps for convenient carrying on the back of an adult. This type of duffle bag is easily folded and compactly stored and carried by an adult when the collapsible stroller is erect and in use. The typical umbrella stroller is great while in use, however, when it is not in use, it is too bulky to carry into malls, amusement parks, etc. 
     Therefore there is a need for a stroller that is lightweight and compact. 
     SUMMARY OF THE INVENTION 
     These and other objects are achieved by a stroller that is lightweight and compact and will fold easily into an average size backpack. The stroller of the present invention permits an entire umbrella stroller, including the wheels, to be folded flat enough, so that it can be carried as a backpack. The backpack can include a cooler compartment that would enable a user to keep drinks cold. 
     While the stroller disclosed herein includes two wheels, it is contemplated that the stroller can also include four swivel wheels, rather than two for added flexibility in turns and tight spaces. 
     Using the stroller embodying the principles of the present invention, a user will never let a child get too tired. Furthermore, the stroller of the present invention can fit in a backpack that could be small enough to take wherever it is needed, and has the option of pulling out a portable stroller out of a backpack when a child gets tired. The stroller of the present invention makes it easy and convenient for a user to carry a backpack that would contain an umbrella stroller. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         FIG. 1  is a perspective view showing a stroller embodying the principles of the present invention in a set up condition. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Other objects, features and advantages of the invention will become apparent from a consideration of the following detailed description and the accompanying drawing figures. 
     Referring to the drawing figures, it can be understood that the principles of the present invention are embodied in a stroller  10  for carrying a child comprises a seat section  12  on which a child rests when stroller  10  is in use. Seat section  12  is preferably formed of flexible material that will be comfortable to the child and will be easily collapsed and deployed as will be understood from the teaching of this disclosure. The seat section includes a first end  14  which is a forward end when the seat section is in use, a second end  16  which is a rear end when the seat section is in use, a first side  18  which extends between the first end of the seat section and second end  16 , a second side  20  which extends between first end  16  second end  18  of the seat section and a longitudinal axis  22  which extends between first end  16  and second end  18  of the seat section. 
     A frame section  30  to which the seat section is attached, the frame section includes a handle unit  34  which is located adjacent to the second end of the seat section and which includes a first cross bar  36  attached to second end  16  of the seat section and which extends between first side  18  of the seat section and second side  20  of the seat section. Handle unit  34  further includes a second cross bar  38  that is spaced apart from first cross bar  36  and which extends between the first side of the seat section and the second side of the seat section. 
     A first support arm  40  is located adjacent to the first side of the seat section and connects one end  42  of the first cross bar to one end  44  of the second cross bar. The first support arm includes a first end  46  which is connected to the one end  42  of the second cross bar  38  and a second end  48  which is spaced apart from the one end of the first cross bar. The first support arm  40  may pivot about a pivot point  49  located between the first end  46  and the second end  48 . A second support arm  60  is located adjacent to second side  20  of the seat section and connects a second end  62  of the second cross bar to a second end  64  of the first cross bar. Second support arm  60  includes a first end  66  connected to the second end of the second cross bar and a second end  68  which is spaced apart from the second end of the first cross bar. The second support arm  60  may pivot about a pivot point  69  located between the first end  66  and the second end  68 . 
     A first support element  80  has a first end  82  pivotably connected to first support arm  40  adjacent to the one end  48  of the first cross bar of the handle unit and a second end  84 . A second support element  90  has a first end  92  pivotably connected to the second support arm adjacent to the second end of the first cross bar of the handle unit and a second end  94 . 
     A first connecting link  100  is located adjacent to the first side of the seat section and includes a first end  102  pivotably connected to second end  84  of the first support element, and a second end  104  located adjacent to the first side of the seat section. The second end of the first support arm is pivotably connected about a pivot point  105  to the first connecting link adjacent to the first side of the seat section. A second connecting link  110  is located adjacent to the second side of the seat section and includes a first end pivotably connected to the second end of the second support element and a second end  116  located adjacent to the second side of the seat section. The second end  68  of the second support arm is pivotably connected about a pivot point  117  to the second connecting link  110  adjacent to the second side of the seat section. 
     Y-shaped support unit  120  includes a first leg  124  having a first end  126  pivotably connected to the second ends of the first support element and the first connecting link, and a second end  128 . Unit  120  further includes a second leg  130  having similar construction as the first leg  124  to support a third wheel (not shown), which is on the second side  20 . A first transverse leg  140  has one end  142  connected to the second end of the first leg of the Y-shaped support unit and a second end  144 . A second transverse leg  150  is provided, which is similar construction as the first traverse leg  40 . The second end of the first transverse leg is located closely adjacent to the second end of the second transverse leg and both second ends are located adjacent to the longitudinal axis of the seat section. A longitudinal leg  156  extends in the direction of the longitudinal axis of the seat section and has a first end  158  pivotably connected to the second ends of the first and second transverse legs of the Y-shaped support unit about a pivot point  159 . Leg  156  has a second end  158 . The longitudinal leg of the Y-shaped support unit extends beyond the first end of the seat section when the stroller is in the set up configuration shown in  FIG. 1 . 
     A block Y-shaped support unit  170  includes a first leg  172  which has a first end  174  pivotably connected to the second end of the first connecting link and a second end  176 . Unit  170  further includes a second leg  180  which has a first end  182  pivotably connected to the second end of the second connecting link and a second end  184 . Unit  170  further includes a first transverse leg  190  which has a first end  194  connected to the second end of the first leg of the block Y-shaped support unit and a second end  198 . Unit  170  further includes a second transverse leg  200  which has a first end  202  connected to the second end of the second leg of the block Y-shaped support unit and a second end  204 . The second ends of the first and second legs of the block Y-shaped support unit are spaced apart from the first end of the seat section. As can be understood from  FIG. 1 , the seat unit is attached to the legs of the block Y-shaped support unit to move therewith and to be supported thereby when the stroller is in the deployed configuration. Unit  170  further includes a first longitudinal arm  220  which has a first end  222  connected to the second end of the first transverse leg of the block Y-shaped support unit and a second end  224  and a second longitudinal arm  230  having a first end  232  connected to the second end of the second transverse leg of the block Y-shaped support unit and a second end  234 . 
     A first wheel unit  240  is rotatably connected to the second ends of the first support arm, the first connecting link and the first leg of the Y-shaped support unit, a second wheel unit is rotatably connected to the second ends of the second support arm, the second connecting link and the second leg of the Y-shaped support unit, and a third wheel unit  244  is rotatably connected to the second ends of the longitudinal leg of the Y-shaped support unit, the first longitudinal arm of the block Y-shaped support unit and the second longitudinal arm of the block Y-shaped support unit. 
     As can be understood from arrows A 1 , A 2  and A 3 , the seat section and the frame section are collapsible to move between a deployed orientation and a folded orientation. In the deployed orientation, the wheel units is spaced apart from the seat section, and in the folded orientation, the wheel units are closely adjacent to the seat section with the third wheel unit located between the first and second wheel units. 
     As can be understood from the foregoing, the frame unit supports the seat unit when the stroller is in use and includes two Y-shaped supporting units and links connecting the frame units together in a manner which allows the two frame units to collapse on each other and lie adjacent to the seat unit in a collapsed configuration and to extend into a seat unit supporting orientation in a deployed orientation. The wheel units are connected to the frame units in a manner to be pivotable between a deployed condition in which the wheel units are oriented to roll over a supporting surface and a stored condition in which the wheel units are oriented at an angle with respect to the deployed condition. 
     For example, to fold the stroller  10  from the deployed orientation shown in  FIG. 1 , the third wheel unit  244  may be moved towards the first wheel unit  240  by rotating about the pivot point  159 , as indicated by the direction arrow A 1 . The causes the first leg  172  and the second leg  180  to pivot about their respective pivot points  105  and  117 , as indicated by the direction arrow A 2 . Then the first support arm  40  and the second support arm  60  may pivot about their respective pivot points  49  and  69 , as indicated by the direction arrow A 3 . To unfold the stroller, the steps discussed above in reference to direction arrows A 1 , A 2 , and A 3  may be reversed. 
     It is understood that while certain forms of the present invention have been illustrated and described herein, it is not to be limited to the specific forms or arrangements of parts described and shown.