Abstract:
A car seat stroller assembly is provided which can be converted from a child car seat into a child stroller, and vice versa. The car seat stroller assembly comprises a child car seat which can be removably secured to a fixed car seat of an automobile, a wheel assembly secured to the seat body at a location near the rear end of the bottom portion of the seat body, and a handle assembly secured to the seat body at a location along the back portion of the seat body. The car seat stroller assembly preferably consists of two wheels which are rotatably mounted to an axle of the wheel assembly. The wheel assembly can be placed in a retracted position to enable a user to secure the car seat stroller assembly to the fixed car seat of the automobile, or in an extended position in which the wheels extend below the bottom portion of the seat body to enable the car seat stroller assembly to be operated as a child stroller. As a result of the wheel assembly being mounted at a location near the rear end of the bottom portion of the seat body, the car seat stroller assembly is highly maneuverable when it is being operated in the stroller mode.

Description:
This application is a division of Ser. No. 09/248,443 filed Feb. 11, 1999. 
    
    
     TECHNICAL FIELD OF THE INVENTION 
     The present invention relates generally to a car seat for infants and toddlers and, more particularly, to a car seat for infants and toddlers which is convertible into a stroller and vice versa. 
     BACKGROUND OF THE INVENTION 
     Car seats which convert into strollers, and vice versa, are generally known in the art. These convertible car seats typically have a retractable wheel assembly comprising four wheels which can be retracted so that the stroller converts into a car seat which can be secured to the fixed car seats of an automobile. In order to convert this type of car seat into a stroller, the seat is unfastened from the fixed car seat of the automobile and the wheel assembly is deployed so that the car seat functions as a baby stroller when the wheels are deployed. One disadvantage of the typical car seat which converts into a stroller, and vice versa, is that the wheel assembly usually adds a relatively large amount of weight to the seat thereby rendering the seat somewhat unwieldy and difficult to attach it to and remove it from the fixed car seat of the automobile. The weight of the wheel assembly is generally attributable to the fact that the wheel assembly comprises four wheels and associated hardware. 
     Batten, U.S. Pat. No. 5,595,393, issued Jan. 21, 1997, discloses an infant car seat stroller which can be converted from a car seat into a stroller, and vice versa. This patent discloses that the car seat comprises a first set of wheels which are attached to a flat bar bracket which, in turn, is affixed to a bottom portion of the seat. The patent discloses that the seat includes a retractable pivoting support on the bottom thereof which is modified by drilling a hole through it and by inserting an axle on which a secondary set of wheels is mounted. This allows the second set of wheels to be retracted so that only the first set of wheels is utilized. 
     This secondary set of wheels disclosed by Batten corresponds to the back wheels of the car seat. This secondary set of wheels can be retracted to allow the car seat stroller to be pulled across the ground using only the front wheels. One of the primary disadvantages of this design is that it only allows the stroller to be pulled in a rearward direction because pushing the stroller with only front wheels would be very awkward and impractical. This design also requires that the user bear most of the weight of the unit and the infant or toddler while lifting up on the handle since there are no wheels to provide vertical support in the two-wheel drive mode. Also, it appears from the text of this patent that the design is only intended to be used with infants, which typically corresponds to children under the weight of 20 lbs. 
     Accordingly, a need exists for a car seat which is convertible into a stroller, and vice versa, which overcomes the weight disadvantages of the four-wheel convertible car seat strollers by utilizing only two wheels, and which overcomes the disadvantages of the known two-wheel strollers associated with the lack of vertical support for the unit and child when the stroller utilizes only two wheels. 
     SUMMARY OF THE INVENTION 
     The present invention provides a car seat stroller assembly which can be converted from a child car seat into a child stroller, and vice versa. The car seat stroller assembly comprises a child car seat which can be removably secured to a fixed car seat of an automobile, a wheel assembly secured to the seat body at a location near the rear end of the bottom portion of the seat body, and a handle assembly secured to the seat body at a location along the back portion of the seat body. 
     The car seat stroller assembly preferably consists of two wheels which are rotatably mounted to an axle of the wheel assembly. The wheel assembly can be placed in a retracted position to enable a user to secure the car seat stroller assembly to the fixed car seat of the automobile, or in an extended position in which the wheels extend below the bottom portion of the seat body to enable the car seat stroller assembly to be operated as a child stroller. 
     In accordance with a first embodiment of the present invention, the car seat stroller assembly utilizes a child car seat which is currently available on the market. The child car seat is retrofitted with the wheel and handle assemblies of the present invention. One child car seat which is suitable for this purpose is sold by Century Products Company. This seat body of the child car seat is retrofitted by attaching the wheel assembly to a protruding portion of the seat body. This protruding portion, which is known as the “Posilock” feature of the car seat, protrudes from the seat body at a location near the rear end of the bottom portion of the seat body and near the bottom end of the back portion of the seat body. 
     The protruding portion of the child car seat is secured to the seat body in a hinging relationship to allow the protruding portion to be retracted and extended. In the extended position, the protruding portion is normally inserted in between the back and bottom cushions of a fixed automobile car seat to assist in securing the child car seat in place in the automobile. The protruding portion can be retracted to allow a user, e.g., a parent, to easily handle the child car seat when it is being removed from and inserted into the automobile. By attaching the wheel assembly to this existing feature on the car seat, the wheel assembly can be easily extended and retracted by extending and retracting the protruding portion of the child car seat. 
     Preferably, the front end of the bottom portion of the seat body has a braking mechanism thereon which substantially prevents the car seat stroller assembly from moving when the braking mechanism is in contact with the floor or the ground. 
     In accordance with a second embodiment of the present invention, the wheel assembly can be suitably attached to any child car seat, including, but not limited to the above-mentioned Century Products Company child car seat. In accordance with this embodiment, the wheel assembly comprises two side members which are transverse to the axle of the wheel assembly. Each side member has a first end, a second end, a first side and a second side. The first ends of the side members are attached to the axle of the wheel assembly. 
     In accordance with this embodiment, when the wheel assembly is placed in the extended position, a first notch formed in each of the second ends of the side members engages a respective pin secured to sides of the seat body. This prevents the wheel assembly from movement in a direction toward the wheels and in a direction away from the bottom end of the back portion. When the wheel assembly is placed in the retracted position, a notch formed in each of the first sides of the side members engages those same pins. This prevents the wheel assembly from movement in a direction away from the back portion of the seat body. 
     In accordance with another embodiment of the present invention, which is the preferred embodiment for the wheel and handle assemblies, the handle assembly is linked to the wheel assembly by a linkage in such a way that when the handle assembly is extended, the wheel assembly is extended until the pins secured to the sides of the seat body are engaged in the first notches formed in the ends of the side members. When a user lifts the seat body in an upwards direction away from the wheels, the pins are removed from the notches formed in the ends of the side members. When the handle assembly is retracted, the linkage causes the wheel assembly to be retracted until the pins are engaged in the notches formed in the sides of the side members. 
     Other features and advantages of the present invention will become apparent from the following description, drawings and claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 illustrates the car seat and stroller assembly of the present invention when the assembly is operating in the stroller mode. 
     FIG. 2A is a rear perspective view of the car seat stroller assembly of the present invention in accordance with a first embodiment wherein the wheel assembly and the handle are in the extended positions so that the assembly can be operated in the stroller mode. 
     FIG. 2B is a bottom perspective view of the car seat stroller assembly of the present invention wherein the wheel assembly is retracted such that the car seat stroller assembly is in the car seat mode and can be attached to the fixed car seat of an automobile. 
     FIG. 3A illustrates the car seat stroller assembly of the present invention in accordance with the preferred embodiment wherein the wheel assembly is extended so that the car seat stroller assembly can be operated in the stroller mode. 
     FIG. 3B illustrates the car seat stroller assembly in accordance with the preferred embodiment of the present invention shown in FIG. 4 when the wheel assembly is between the fully extended and fully retracted positions. 
     FIGS. 4A and 4B illustrates the wheel and handle assembly of the car seat stroller assembly of the present invention shown in FIGS. 3A and 3B which demonstrates the manner in which the handle and wheel assemblies operate in conjunction with one another to cause the handle assembly to be extended as the wheel assembly is extended and to cause the handle assembly to be folded as the wheel assembly is retracted. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 illustrates the car seat stroller assembly  1  of the present invention in accordance with a first embodiment wherein the car seat stroller assembly  1  has been converted from a car seat into a stroller by extending a wheel assembly  2  having two wheels  3 , only one of which is shown in FIG. 1, and by extending a handle assembly  5 . FIG. 1 also illustrates a silhouette  7  of a woman pushing the car seat stroller assembly  1  in which a child  9  is secured. In accordance with this embodiment, a car seat which is sold by Century Products Company has been retrofitted by attaching the wheel assembly  2  and the handle assembly  5  of the present invention thereto. 
     FIG. 2A illustrates a rear perspective view of the car seat stroller assembly  1  shown in FIG. 1 which illustrates the manner in which the wheel assembly  2  of the present invention is secured to the car seat body  6 . The car seat sold by Century Products Company comprises an extension  11  which is intended to be inserted into an opening in the portion of the fixed automobile car seat (not shown) where the vertical backing member of the fixed automobile car seat abuts the horizontal seat member of the fixed automobile car seat. When the car seat body  6  is placed firmly against the fixed automobile car seat and the insert  11  is inserted between the vertical backing member and the horizontal seat member, the insertion member  11  assists in preventing movement of the car seat body  6 . 
     The wheel assembly  2  is attached to the insertion member  11  via a fastening device  14 , which may be, for example, screws, bolts, rivets, adhesives, etc. When the wheel assembly  2  is in the extended position, as shown in FIG. 2A, the wheels  3  extend below the bottom surface of the insertion member  11  so that when the wheels are in contact with the ground, they fully support the car seat  6 . The insertion member  11  hinges about a horizontal axis (not shown) to allow it to be extended and retracted. When the wheel assembly  2  is in the extended position, the insertion member  11  to which the wheel assembly  2  is attached locks into place so that the wheels cannot retract when the car seat stroller assembly is operating in the stroller mode. 
     The car seat  6  is also retrofitted with a handle assembly  5  which comprises two vertical tube members  12  and  13 , which preferably are telescoping tubes to enable the handle assembly  5  to be extended and retracted. The handle assembly  5  is attached to the car seat via brackets  16  and  17 , which are fixedly attached to the car seat body  6 , and by mating tube portions  19  and  21  which receive the ends of the vertical tube members  12  and  13  at openings  23  and  24  in the mating tube portions  19  and  21 . The brackets  16  and  17  are secured to the body of the car seat  6  via an attachment mechanism such as, for example, bolts  26  and  27 . A horizontal support member  29  secures the vertical tube members  12  and  13  to the upper portion of the back  32  of the car seat body  6  and prevents the vertical tube members  12  and  13  from substantial movement in the directions transverse to the axial directions of the vertical tube members  12  and  13 . 
     When operating the car seat stroller assembly  1  in the stroller mode, mechanism comprised of locking members  36  and  37 , which are attached to horizontal support member  29  provide a mechanism for releasing and locking the vertical tube members  12  and  13 . In order to extend the handle, the locking members  36  and  37  are placed in the position parallel to the vertical tube members  12  and  13  and the user exerts an upward force on the handle  41 . Once the vertical tube members  12  and  13  have been lifted to the desired vertical position, the locking mechanisms  36  and  37  are pushed down so that they are substantially transverse to the vertical tube members  12  and  13  and the vertical tube members  12  and  13  are thereby locked into place. It should be noted that different types and configurations of handles may be used with the car seat stroller of the present invention. Therefore, the present invention is not limited to use with any particular type of handle assembly. 
     The wheel assembly  2  is extended manually by simply pulling the insertion member  11  or one or more of the wheels  3  in a direction away from the bottom  43  of the seat body  6  to thereby rotate the wheel assembly  2  into the extended position. In order to retract the wheel assembly  2 , the user simply pushes the wheel assembly  2  in a direction toward the bottom  43  of the car seat body  6 . The insertion member  11  is known as the “Posilock” feature of the Century Products Company car seat. 
     It will be understood by those skilled in the art that the present invention is not limited to use with any particular type or brand of car seat The Century car seat was chosen in accordance with this embodiment due to the Posilock Feature, which makes the Century Products Company car seat very suitable for retrofitting with the wheel assembly  2  of the present invention. It will be understood by those skilled in the art that a wheel assembly identical or similar to the wheel assembly  2  shown in FIGS. 1 and 2A can be attached to the bottom and rear portion of any child car seat. However, it should be noted that, regardless of the car seat with which the retrofitting assembly of the present invention is implemented, it is important that the wheel assembly be attached to the bottom and rear portion of the car seat because this location allows the stroller to be pushed or pulled with a high degree of maneuverability. 
     FIG. 2B is a bottom perspective view of the car seat stroller assembly  1  which illustrates the wheel assembly  2  in the retracted position. This view also illustrates the front brakes  44 , which preferably are rubber blocks secured to the front, bottom portion of the car seat body  6 . The brakes  44  prevent the bottom  43  of the car seat body  6  from being scratched when the front, bottom portion of the car seat body  6  is placed against the ground or floor. The brakes  44  allow the assembly to be securely placed at rest. 
     In the retracted position, the wheels  3  are flush against the body  6  of the car seat. Two substantially U-shaped support members  45  and  46  are shaped to engage square or rectangular-shaped sections on the body  6  of the seat. By using these U-shaped support members  45  and  46  to couple the wheels  3  with the wheel assembly  2 , the wheels  3  are held snugly against the sides of the car seat body  6  and thus do not substantially extend beyond the sides of the car seat body  6  when the wheel assembly  2  is in the retracted position. This feature of the present invention enables the car seat stroller assembly  1  to be easily handled by a user when securing it to and removing it from the fixed automobile car seat (not shown). Furthermore, in the retracted position, the wheel assembly  2  and the wheels  3  slightly expand the effective base of the seat thereby providing it with additional lateral support when it is secured to the fixed automobile car seat. 
     FIG. 3A illustrates a cross-sectional rear perspective view of the car seat stroller assembly  50  of the present invention in accordance with a second embodiment. In accordance with this embodiment, when the wheel assembly  55  is in the extended position to place the car seat stroller assembly  50  in the stroller mode, the wheels  57  are disposed below the bottom surface  59  of the body  52  of the car seat  52 . In this position, the wheel assembly  55  and the wheels  57  provide total vertical support for the car seat stroller assembly  50 . The handle assembly used in this embodiment is substantially identical to the handle assembly  5  shown in FIGS. 1,  2 A and  2 B in that it comprises vertical tubular members  61  and  62 , which preferably are telescoping tubular members, which fit into openings  67  and  68  in vertical tubular mating portions  73  and  74 , respectively. The vertical tubular mating portions  73  and  74  are attached to brackets  78  and  79  by any suitable attachment means such as, for example, welding, bolts, rivets, etc. 
     When the car seat stroller assembly  50  is in the stroller mode, i.e., when the wheel assembly  55  is fully extended and locked into place, pins  81 , which are secured to brackets  78  and  79 , mate with a U-shaped slot  85 . The U-shaped slot  85  is of sufficient length to prevent the possibility of the pin  81  coming out of the slot  85  when the car seat stroller assembly  1  is operational in the stroller mode. Also, a bolt and washer assembly  87  is sufficiently tight to maintain a constant amount of pressure and friction between the brackets  78  and  79  and the transverse members  89  of the wheel assembly  55 . 
     FIG. 3B illustrates the car seat stroller assembly  50  with the wheel assembly  55  partially retracted, i.e., between the fully-extended and fully-retracted positions. In order to retract the wheel assembly  55 , the user simply lifts the body  52  of the car seat assembly  50  so that the pin  81  is moved in an upward direction until it is out of the slot  85  and then the wheel assembly  55  is folded in an upward direction until the pins  81  are received in the slots  88  of the transverse members  89  of the wheel assembly  55 . The slots  88  are L-shaped so that once the pins  81  have been received in the slots  88 , the pins  81  are moved vertically relative to the slots  88  until the pins  81  abut the ends of the slots  88  closest to the wheels  57 . The mating of pins  81  with the slots  88  substantially prevents lateral and vertical movement of the pins  81  within the slots  88  when the wheel assembly  55  is in the retracted position. Any movement of the wheel assembly  55  when it is in the retracted position is prevented by the friction fit created by the bolt and nut assembly  87  and  91 . 
     When the wheel assembly  55  is in the fully-retracted position (not shown), the wheels  57  are disposed against the sides of the car seat body  52  and are completely unobtrusive. By closely adapting the wheel assembly  55  to the shape of the car seat body  52 , the car seat stroller assembly  50  can be easily handled by the user when the user is placing the assembly in and removing the assembly from the vehicle. 
     FIGS. 4A and 4B illustrate the wheel and handle assembly of the present invention in accordance with the preferred embodiment. In accordance with this embodiment, the wheel assembly and handle assembly are linked together in such a manner that retraction of the handle effectuates retraction of the wheel assembly and extension of the handle assembly effectuates extension of the wheel assembly. The handle assembly  101  is pivotally attached on each end thereof to a linking member  103  by a fastening device  104 . The fastening device  104  allows rotational movement of the handle assembly  101  with respect to the linking member  103  while also securing them together. Those skilled in the art will note that this rotational arrangement can be achieved in a plurality of different ways which are well known to those skilled in the art. 
     A linking member  106  is rotationally secured on one end  107  to the wheel assembly  102  and on the other end  108  to the handle assembly  101 . FIG. 4A illustrates the handle assembly  101 , the linking member  103  and the wheel assembly  102  when the handle and wheel assemblies  101  and  102  are in the retracted positions. When the portion  109  of the handle assembly  101  intended to be gripped by the user is rotated in a clockwise and downward direction toward the wheel assembly  102 , the lower end  111  of the handle assembly  101  is rotated upwards away from the wheel assembly  102  thereby exerting an upward force on the end  108  of the linking member  106 . This upward force exerts an upward force on the end  107  of the linking member  106  which, in turn, causes the wheel assembly  102  to be pulled into the retracted position shown in FIG.  4 A. 
     Conversely, when the wheel assembly  102  is in the fully-retracted position and the end  109  of the handle assembly  101  is rotated upwards in the counter-clockwise direction away from the wheel assembly  102 , the end  111  of the handle assembly  101  is rotated in the downwards in the counterclockwise direction toward the wheel assembly  102 . This causes a downward force to be exerted on the end  108  of the linking member  106  which, in turn, causes a downward force to be exerted on the end  107  of the linking member  106 , thus causing the wheel assembly  102  to be rotated in the downward direction until it is fully extended, as shown in FIG.  4 B. 
     As with the embodiments shown in FIGS. 2A-3B, in the embodiment shown in FIGS. 4A and 4B, the wheel assembly  102  contains slots  112  and  113 , which serve identical functions to that of the slots  85  and  88  shown in FIGS. 3A and 3B. Also, a nut and bolt arrangement  115  is utilized in the embodiment shown in FIGS. 4A and 4B in the same manner in which the nut and bolt assembly  87  and  91  is utilized in the embodiment shown in FIGS. 3A and 3B to secure the wheel assembly  55  in place. 
     It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments discussed above with respect to FIGS. 1-4B. Those skilled in the art will understand that the present invention is not limited to any particular type of arrangement or configuration for the handle and wheel assemblies implemented with the car seat stroller assembly of the present invention. The embodiments discussed above are intended to demonstrate the various advantageous features of the present invention, but those skilled in the art will understand that the invention is not limited to these particular features. Those skilled in the art will understand that other modifications, deletions and adaptations can be made to the embodiments discussed above which are all within the scope of the present invention.