Abstract:
A small size bicycle for use by young children having front wheel pedal drive and adapted to have an attached training wheel assembly.

Description:
FIELD OF THE INVENTION 
     This invention is directed to a small size bicycle, approximately ten inches high, which is usable by children aged 11/2 to 3 years. More particularly, the present invention is directed to a small size bicycle having a front wheel direct drive, being of sturdy, lightweight, comfortable construction and being readily adapted to be provided with a very stable training wheel assembly. 
     BACKGROUND OF THE INVENTION 
     Bicycles have long been used for recreation and, more recently, relatively small sized front wheel drive sidewalk bicycles have been developed for young children. These sidewalk bicycles have not been fully satisfactory for very young children, aged 11/2 to 3 years old, since these sidewalk bicycles are generally a bit too large, too heavy and too stiff, i.e. too sensitive to minor shocks from hard, rough surfaces, for comfortable use by very young children. Merely reducing the overall size of prior art sidewalk bicycles can achieve same weight reduction but the prior art configurations are not adapted to substantial size reduction on account of a usual elaborateness of design. 
     SUMMARY OF THE INVENTION AND OBJECTS 
     A principal object of this invention therefore is to provide a two-wheel bicycle having a configuration which permits the bicycle to be made in a very small size while providing a device which is lightweight, comfortable and stable and which can be easily operated by small children, e.g. aged 11/2 to 3 years. 
     These and other objects will be apparent to those skilled in the art from the following description taken in conjunction with the drawing wherein: 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an assembly view of a particular embodiment of a bicycle in accordance with the present invention. 
     FIG. 2(a) is a detailed exploded view of a bicycle of the type shown in FIG. 1. 
     FIG. 2(b) shows in some detail a particular nesting connection on the frame of the bicycle of FIG. 1. 
     FIGS. 3(a)-(e) show plan and elevation views of the rear section of the frame of a bicycle of the type shown in FIG. 1. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     With reference to the drawing, FIG. 1 shows a bicycle in accordance with present invention comprising a tubular metal frame 10, e.g. suitably made of steel tube, having a goose-neck shape midsection 12 which comprises, in the embodiment illustrated, a generally straight portion 14, an inclined generally &#34;C&#34;-shaped forward portion 16 and a bow-shaped portion 18 intermediate the straight and &#34;C&#34;-shaped portions with bow-shaped portion 18 curving in a direction opposite to the &#34;C&#34;-shaped portion 16. The length of the straight portion 14 is about one-half the diameter of the &#34;same-sized&#34; front and rear wheels 74 and 104. In the embodiment illustrated, the midsection 12 is integral, i.e. unitary in that it is formed by mechanical deformation of a single piece of metal tube to provide a shape having smoothly curved bends which impart a significant degree of resilience or springiness to the metal frame and dampen shocks which may occur due to uneven terrain. The span of midsection 12 from the straight section 14 to the end of &#34;C&#34;-shaped portion 16 is selected so that a young child aged 11/2 to 3 years old can reach the pedals at all degrees of rotation. 
     With particular reference to FIGS. 3(a), 3(b), and 3(c), the rear section 20 is a metal tube, suitably of about one-half the diameter of the tube of the midsection 12, and has a configuration formed by bending the metal tube in double at 22 in a first plane, and bending it again in a direction which is about at a right angle to the first plane to provide a tube configuration having, with reference to FIGS. 3(a), 3(b), and 3(c), a &#34;U&#34;-shape 22 when viewed from the top and &#34;U&#34;-shapes 24, 25 in planes substantially parallel to each other, and substantially perpendicular to the plane of &#34;U&#34;-shape 22 when viewed from either side. The aforedescribed bending is accomplished in a manner to avoid any creasing or crimping of the metal tube so as to result in smooth arcuate bends. The end portions 26, 28 of parallel extensions 21, 23 of the tubular rear section 20 are subjected to mechanical deformation so as to be shaped to conform to the cylindrical periphery of the lower portion of the bow-shaped portion 18, which as shown particularly in FIGS. 2(b) and 3(a), nests in the conforming configuration 27 established by the deformation of end portions 26, 28 and to which extensions 26, 28 are affixed, e.g. by brazing or welding at 29, 31. This nesting support engagement of bow-shaped portion 18 with extensions 26, 28, enhances the resilience of tubular metal frame 10. As shown in FIG. 2, the &#34;U&#34;-shaped portion 22 is positioned closely adjacent the upwardly extending portion 14 of midsection 12 to which it is fixedly attached at 33 e.g. by brazing or welding. The forward section of frame 10 is a cylindrically shaped head tube 30 which is fixedly attached, e.g. by brazing or welding at 17 to the end of &#34;C&#34;-shaped portion 16 which is remote from the straight portion 14. 
     A steerable assembly 32 is engaged to head tube 30 and comprises a handle bar 34, suitably made of steel tube fixedly mounted on handle bar stem 36, also suitably made of steel. Handle bar stem 36, which is split as shown at 37 in FIG. 2(a), passes through head tube 30 and telescopically surrounds fork neck 38 and is fixed thereto by adjustment of bolt 40 and nut 42 of clamp 44; clamp 44 is covered by a clamp cover 46. Head tube 30 is spaced from fork cover flange 48 by plastic washer 50 and flange 48, which is fixed to fork neck 38 by metal rivets is attached e.g. by rivets 52 to front fender 54, which is suitably made of steel sheet. In the preferred embodiment shown in the drawing, front fender 54, suitably made of a rigid thermoplastic resin such as polyvinylchloride (PVC) has a curved, concave shape, of arcuate cross-section, which slightly overlaps front tire 74 and extends between about one to one and one-half quadrants, as indicated at 63 in FIG. 1, above front wheel axle 68. Front fender 54 is fixed to flange 48 as described above and extends about equally to the front and rear of flange 48. The shape and location of front fender 54 provides optimized protection to the rider while not overly encumbering the bicycle. Fork 56 and fork neck 38, both suitably made of steel tubing, are fixedly joined by a clamp at 58. Fork branches 57, 59 fit telescopically within fork sleeves 60, 62 and are fixedly attached thereto by means of bolts 64, and nuts 66. Sleeves 60, 62 suitable made of metal sheet are rotatably engaged at 67, through a suitable bearing arrangement, to front wheel axle 68 which is integrally connected to oppositely extending, radial pedal shafts 70, which support pedals 72. Front tire 74, suitably made of ethylene vinyl acetate (EVA), is mounted on wheel 75, suitably made of fiber-reinforced nylon, and wheel 75 is fixed to axle 68 by press fitting, and is driven directly from pedals 72. 
     A rear wheel assembly, indicated at 80, comprises metal tabs 82, 84 attached to parallel extensions 21, 23 of tubular rear section 20, e.g. by brazing or welding as indicated at 91, 93. Metal tabs 82, 84 are parallel and extend downwardly away from upwardly extending portion 14 of mid-section 12 and are slotted at 86, 88 and notched at 90, 92. Slots 86, 88 receive the extensions 94 of symmetically arranged training wheel brackets 98. Notches 90, 92 rotatably engage axle 102 of rear wheel 104. Axle 102 is fixedly attached to rear wheel 104, e.g. by press fitting and is held in place, together with bracket pair 98, by nut and washer arrangements 106. Apertures 108 in the brackets 98, closely surround axle 102 and, together with bracket extensions 94, maintain bracket pair 98 in a fixed position which enables symmetrically arranged training wheels 110, 112, when fixed to bracket pair 98 by nut and bolt arrangement, to have their contact bearing surfaces in the same plane as that of front wheel 74 and rear wheel 104. 
     A &#34;U&#34;-shaped tubular member 120 is fixedly attached to upper &#34;U&#34;-shaped portion 22, e.g. at 121 by brazing or welding as particularly illustrated in FIG. 3(a). &#34;U&#34;-shaped member 120 is at an upward angle with &#34;U&#34;-shaped portion 22 so that it can serve as a package holder or a push bar for the bicycle. Rear fender 130, suitably made of a thermoplastic resin such as polyvinylcholoride, PVC, is fixedly attached to tubular rear section 20, suitably with rivets as indicated at 123, 125 in FIG. 3(c). In the preferred embodiment shown in the drawing, rear fender 130 has a curved, concave shape, of arcuate cross-section, which slightly overlaps rear tire 104, suitably made by EVA and which extends about one to one and one-half quadrants, as indicated at 133 in FIG. 1, above rear wheel axle 102. Rear wheel axle 102 is press fitted onto rear wheel 105. Rear fender 130, is located below the first &#34;U&#34;-shaped bend 22 and nests in said &#34;U&#34;-shaped bend and is fixed thereto as described above. The shape and location of rear fender 130, suitably made of thermoplastic material provides optimized protection to the rider while not overly encumbering the bicycle. Seat 131, suitably made of steel, is fixedly mounted on seat post 132 and seat post 132 is split as shown at 134 in FIG. 2, and fits slidably within straight portion 14 of frame 10. The height of the seat is adjusted to the needs of the user and clamp 140, mounted on straight portion 14, is tightened by nut and bolt arrangement 144. 
     A particular advantage of the present invention is that its uncomplicated design enables the construction of a very small (e.g. 10 inches high) comfortable, stable and easily propelled forward drive bicycle. Other advantages are that the unitary metal tube frame member has a configuration which is resilient and absorbs the minor shocks due to rough terrain. Further the hollow goose-neck frame member together with the front wheel drive provides a stable arrangement which is also lightweight.