Abstract:
A foldable buggy having two side frames and a child support means attached to each side frame by a respective support member, each side frame having forward strut means, rear strut means and vertical strut means, the forward strut means comprising an upper section and a lower section pivotally connected to each other to allow folding and unfolding, the support member being slidably mounted on the lower section, and including a strut means pivotally attached to the upper section and the support means, such that when the buggy is folded from an unfolded state to a folded state, the strut means causes the support member to slide down the lower section.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to push chairs or prams for infants, and in particular foldable push chairs or prams.  
         [0002]     The main aspect of the present invention relates to the folding mechanism for the side frames.  
       BACKGROUND OF THE INVENTION  
       [0003]     The standard folding baby buggy consists of two side frames separated by cross-bars and having a seat or cot mounted between them. Some push-chairs can have the two side frames moved together for folding (3-dimensional fold); others have the distance between the side frames fixed (2-dimensional fold). The standard form of side frame has a delta-shaped side frame, with a front sloping strut or bar with a front wheel at its bottom end and a handle at its top end, a rear sloping bar with a rear wheel at its bottom end and hinged at its top end to a point around the middle of the front sloping bar, and a base bar, linking the two sloping bars, which is roughly horizontal and located toward the bottom end of the rear sloping bar. The base bar is hinged at about its mid-point.  
         [0004]     The side frame can then be folded by bending the base bar at its central hinge, with its two halves coming together, and bringing together the rear sloping bar and the bottom end of the front sloping bar.  
       OBJECT OF THE INVENTION  
       [0005]     An object of the invention is to provide a new side frame folding mechanism.  
       SUMMARY OF THE INVENTION  
       [0006]     According to the invention, there is provided a foldable buggy having two side frames and a child support means attached to each side frame by a respective support member, each side frame having forward strut means, rear strut means and vertical strut means, the forward strut means comprising an upper section and a lower section pivotally connected to each other to allow folding and unfolding, the support member being slidably mounted on the lower section, and including a strut means pivotally attached to the upper section and the support means, such that when the buggy is folded from an unfolded state to a folded state, the strut means causes the support member to slide down the lower section. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]     A baby buggy embodying the invention will now be described, by way of example, without limitation to the scope of the invention, and with reference to the drawings, in which:  
         [0008]      FIG. 1  is a diagrammatic side view of the buggy frame in the unfolded position;  
         [0009]      FIG. 2  is a diagrammatic side view of the buggy frame during folding; and  
         [0010]      FIG. 3  is a diagrammatic side view of the buggy frame in the folded position.  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0011]      FIG. 1  is a diagrammatic side view of the buggy frame in an unfolded state, ready for use (“the unfolded position”). The buggy consists of two side frames, one for each side, which are spaced apart by cross struts.  FIG. 1  shows one side frame; the opposite side frame is identical. The frame consists of a front sloping bar  10 , a rear sloping bar  11 , and a rear vertical bar  12  (the term “vertical” is used merely for labeling purposes, as the bar  12  is more nearly vertical than the bars  10  and  11 ). The front and rear bars  10  and  11  have wheels  13  and  14  attached at their lower ends. A handle (not shown) is attached at the upper end of the front sloping bar  10 ; the handle may consist of a cross-bar between the two side frames. The lower end of the front sloping bar  10  is preferably curved, as shown in the figures, to bring the front wheel  13  backward to some extent.  
         [0012]     The bars  10 ,  11  and  12  are attached to each other by hinges or pivots  15 - 17 . The front bar  10  is made up of two separate segments, the upper front bar segment  10 A and the lower front bar segment  10 B, which are pivotally connected by a hinge  18 . When the frame is locked in the unfolded position, the hinge  18  is held in the position shown in  FIG. 1 , with the bar  10  straight.  
         [0013]     A seat or cot can be attached to the buggy frame, using a support member  20 . Alternatively a seat which is convertible to a cot can be attached to the buggy frame. A cot  30  is shown, in broken lines, attached to the buggy frame in  FIG. 1 . The cot is supported on a cross bar mounted between the support members  20  on each side of the buggy (the cross bar is not shown in the figures). The cot  30  can be rigid, if the buggy is only to fold front to back, or flexible, if the buggy is to fold side to side also.  
         [0014]     The support member  20  is slidably attached to the lower front bar  10 B. The support member  20  has a bulbous protrusion which engages with a corresponding groove, running along the length of the lower front bar  10 B, so that the support member  20  can slide along the lower front bar  10 B. A rod  21  connects the support member  20  to the upper front bar  10 A; more specifically, the rod  21  is attached to the upper front bar  10 A at pivot point  22  and to the support member  20  at pivot point  23 .  
         [0015]     Referring to  FIG. 2 , the hinge  18  allows the front bar  10  to fold, in order to collapse the frame. The upper front bar  10 A and lower front bar  10 B pivot about the hinge  18 , the upper front bar  10 A pivoting towards the rear wheel  14 , as indicated by arrow  19 . This allows the buggy to be folded into a compact form for storage (the folded position). As the upper front bar  10 A pivots from the unfolded position to the folded position, the support member  20  is caused to slide downwards along the lower front bar  10 B. Similarly, as the buggy is converted from the folded position to the unfolded position, the support member  20  is caused to slide upwards along the lower front bar  10 B. When the buggy is in the unfolded state, the support member  20  abuts against a stop  24 , which prevents the support member  20  from sliding further upwards along the lower front bar  10 B. The stop  24  can also incorporate a locking mechanism, locking the stop  24  and the support member  20  together, to lock the buggy in the unfolded position.  
         [0016]      FIG. 3  is a diagrammatic view of the side frame in the folded position. In the folded position, the dimensions of the frame are such that support member  20  is located roughly midway between the hinge  18  and the edge of the wheel  13 . The support member  20  is located a distance l 1  from the hinge  18  and a distance l 2  from the outer edge of the wheel  13 , where distances l 1  and l 2  are approximately equal.  
         [0017]     The support member  20  is attached to the cot  30  roughly midway between the front end and the rear end of the cot  30 . The length of the base of the cot  30 , between the front and rear ends, is roughly the distance l 1 +l 2 . The cot  30  is able to pivot about the support members  20 , so that the cot base may be horizontal when the buggy is in the unfolded position. When the buggy is in the folded position, the cot can pivot about support members  20  so that the base of the cot lies parallel with the lower front bar  10 B.  
         [0018]     As the buggy frame is folded from the unfolded to the folded state, the support member  20  slides along the lower front bar  10 B, and the cot  30 , which is attached to the support member, also moves with the support member, towards the front wheel  13 . When the buggy is in the folded state, as shown in  FIG. 3 , the base of the cot  30  is parallel with the lower front bar  10 B and the front and rear ends of the cot  30  are close to the ends of the folded pushchair. The rear end of the cot  30  is close to the hinge  18  and the front end of the cot  30  is close to the outer edge of wheel  13 . Therefore, when the buggy is in the folded state the cot does not protrude out from the edges of the folded buggy frame. In going from the unfolded position to the folded position, the support member  20  slides down the lower front bar  10 B until the support member is located half-way between the hinge  18  and the outer edge of wheel  13 . Therefore the length of the folded buggy is no longer than the length of the cot. This makes the folded buggy easy to store as the different components fold compactly together.  
         [0019]     If a seat is attached to the buggy frame in place of the cot  30 , the length of the seat from its top to its bottom should be roughly equal to the distance l 1 +l 2 . The support members  20  should be attached to the seat roughly midway between the top and bottom of the seat. Therefore, when the buggy is in the folded state, the seat will not protrude from the edges of the folded buggy frame.  
         [0020]     Alternatively, the support member can be attached to the cot  30  at a point other than the mid-point along the base of the cot. The dimensions of the buggy frame will be adjusted accordingly so that when the buggy is in the folded state, the cot will not protrude from the edges of the folded buggy frame.  
         [0021]     The buggy frame of the present invention can be used for a three or four wheeled buggy. For a four wheeled buggy, the chassis will consist of two side frames of  FIGS. 1-3 , each having a front and back wheel, the side frame being separated by cross struts. For a three wheeled buggy, each side frame will have a respective rear wheel  14 ; however, the front wheel  13  will be shared.  
         [0022]     Alternative embodiments using the principles disclosed will suggest themselves to those skilled in the art upon studying the foregoing description and the drawings. It is intended that such alternatives are included within the scope of the invention, which is limited only by the claims.