Abstract:
A toy adapted to crawl down a vertical surface has a frame carrying a shell at one end and a roller at the other. The roller has a corrugated surface of soft tacky material such that the roller will roll slowly down a vertical surface.

Description:
INTRODUCTION 
     This invention relates to a toy, and in particular to a toy which will run down a vertical surface. 
     BACKGROUND 
     Toys which have the facility to run down vertical surfaces are well known in the toy art. 
     GB No. 1402126 discloses a toy having a shell and a magnetic roller housed in the shell. The roller adheres to a vertical ferromagnetic surface and the weight of the shell and roller cause the toy to roll downwards, the magnet keeping in touch with the surface. The specification also envisages a roller which may be electrostatically charged by rubbing and so adhere to a surface that way. 
     GB No. 696660 also shows a falling toy utilising a magnetic roller to attach it to a vertical surface. 
     U.S. Pat. No. 3,810,515 uses a magnet or a powered fan forming a vacuum to hold the toy against a surface. 
     GB No. 716949 discloses a toy which uses a plurality of magnets or suction cups which are mounted on spokes of a wheel. A spring or weight causes the wheel to rotate, the suction cups sequentially sticking to and lifting off a surface to effect a walking action. The specification envisages the use of a sticky substance on the ends of the spokes in place of the suction cups. 
     These toys have the drawback that they are limited to use on ferromagnetic surfaces or that they are complicated and expensive to produce, utilising many parts. 
     SUMMARY OF THE INVENTION 
     According to the present invention, there is provided a toy comprising a shell and at least one roller supported by the shell for rotation relative thereto, the outer peripheral surface of the roller being ridged to define a plurality of angularly spaced axially extending crests of sticky material. When placed in contact with a vertical surface the roller will stick to the surface but will roll down the surface due to the weight of the roller, carrying the shell with it. 
     In another aspect the invention provides a toy comprising a frame, a roller mounted on the frame for rotation about an axis and a shell mounted on the frame, the shell being open at a side thereof, wherein the roller has a circumferential surface formed by a plurality of arcuate crests of sticky material, the crests extending in the axial direction of the roller, whereby the said open side of the shell may be placed against a vertical surface, a first crest of the roller contacting the surface and sticking thereto, the weight of the shell frame and roller causing the roller to roll downwards about the first crest to bring a second crest into sticking contact with the surface and detach the first crest from the surface, and so on. 
     In another aspect the invention provides a toy comprising a frame having two arms connected between their ends by a cross-bar, a shell loosely mounted on first ends of the arms to one side of the cross bar, a roller rotatably mounted on second ends of the arms on an opposite side of the cross bar to said one side, said roller having a circumferential surface comprising ridges extending substantially parallel to the axis of rotation of the roller, and said ridges being formed of tacky material whereby said toy may be adhered to a vertical surface, said roller rotating under the weight of the toy to bring each of said ridges in turn into sticking contact with the surface such that said toy moves vertically down the surface. 
     According to yet another aspect the invention provides a toy comprising a shell and a roller mounted within the shell for rotation, the shell defining an opening through which a circumferential surface of the roller projects for contact with a supporting surface, wherein the circumferential surface of the roller is corrugated, the corrugations extending transverse to a direction of rotation of the roller, the corrugations being formed of tacky material, the tackiness of the material being such that where upper and lower corrugations of the circumferential surface are pressed against a vertical surface the upper corrugation is slowly peeled from the surface by the weight of the shell and roller, the roller pivoting on the surface about the lower one of the corrugations to bring a corrugation beneath the lower one into sticking contact with the surface. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of one embodiment of a toy according to the invention; 
     FIG. 2 is a section taken through line II--II of the toy of FIG. 1 and showing the toy in contact with a vertical surface; and 
     FIG. 3 is a section taken through the line III--III of FIG. 2. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to the drawings, the toy shown therein comprises a shell 10 which can take any appropriate shape such as to simulate an insect, e.g. a beetle, or a toy motor car, and a roller 11 supported inside the shell 10 on an H-shaped frame 12 for rotation. 
     The shell 10 is vacuum formed from thin plastics material and preferably is decorated according to the desired shape, e.g. to simulate an insect or motor car. The shell has a peripheral flange 24 defining an opening 27. 
     The roller 11 comprises a cylindrical former 13 which carries an extruded band 14 of resilient sticky plastic material which is generally cylindrical in shape and has a plurality of axially extending lobes 14a-14f of half-cylindrical shape, as seen in FIGS. 1 and 2. 
     The former 13 is integrally moulded from a plastic material and comprises a tubular cylindrical axle 15 having a through bore 16. A flange 17 extends around the circumference of the axle 15. Two pins 18 extend laterally of the flange 17. The band 14 of resilient sticky polymer material is extruded about the former 13 and is held in position axially by the flange 17 and circumferentially by the pins 18. 
     The constituents of the polymer material of the band 14 are selected to provide a soft or resilient material which will be readily and resiliently deformed by a weight of a few ounces. The material includes a tackifier which imparts a tackiness or stickness to the surface of the material. Such polymer materials and their constituents are well known and it is necessary only to blend suitable constituents to achieve the desired degree of deformability and tackiness according to the weight of the toy. The tackiness is such that dirt adhering to the circumference of the band may be removed by placing a piece of adhesive tape on the circumference of the band and removing it, the tape carrying the dirt with it. 
     The preferred constituents of the band material are polymerizing styrene, butadiance, napthenic oil, calcium carbonate and hydrogenated polyterpene resin, the latter being the tackifier. 
     The roller 11 is mounted in the H-shaped frame 12 which will now be described in more detail. 
     Referring to FIG. 3, the frame 12 comprises two upights 20 connected between their ends by a cross-bar 21. 
     First ends 20a on one side of the cross-bar 21 carry axle supports 22 which project inwardly of the frame. The cylinder 15 of the roller 11 is mounted on the axle supports 22 which project in to the bore 16. The frame 12 is of flexible plastic material allowing the ends 20a to be drawn apart for mounting the roller 11 on the ends. 
     Second ends 20b of the H-shape frame 12 on the opposite side of the cross-bar 21 project through apertures 23 in the shell 10. Nibs 20c are formed on the ends 20b and the shell is trapped between the nibs 20c and cross-bar 21, the frame 12 thus being loosely mounted in the shell. A stabiliser 28 extends laterally on each side of the cross-bar 21 (see FIG. 2) and serves to limit the degree of movement of the frame and so keep the roller 11 clear of the inside surface of the shell 10. The frame is mounted in the shell by clipping the nibs 20c through the apertures 23, the flexibility of the frame 12 and thin walled shell 10 allowing this. 
     The roller 11 then is rotatably mounted on one end of the frame 12, the other end being loosely mounted in the shell to swing in the shell by a limited amount. 
     The toy will attach to and gradually run down a vertical surface in a manner which will now be described. Considering the roller 11 in the position shown in FIG. 2, that is to say with two half-cylindrical lobes 14a and 14b in contact with vertical surface 25, the moment exerted by the mass of the toy will place lobe 14a under tension and lobe 14b under compression. Lobe 14a will be pulled away from the surface 25 and lobe 14a will alone hold the roller on the vertical surface 15 momentarily until lobe 14c swings about the area of contact between lobe 14b and the wall 25 to come into contact with the surface 25 to reinforce the holding force and prevent the roller falling off the surface 25. 
     The band 14 is of resilient material. The effect of this is that as lobe 14c swings around it hits the wall 25 with some force and so deforms, forming a flat contact area between the lobe 14c and the wall. The upper part of the contact area of lobe 14a is peeled away gradually, but with somewhat increasing speed, as the roller rotates to detach suddenly from the wall before the lobe 14c contacts the wall. 
     The roller 11 will consequently run down the surface 25 carrying the shell 10 with it, the rate of movement depending upon a number of parameters including the mass of the toy, the degree of stickiness of the lobes 14 and the nature of the surface 25. 
     The shell 10 pivots on the frame 12 so that its front or lower end 26 bears against the surface 25. The flange 24 serves to prevent the edge of the shell digging into the textured surfaces which would impede the progress of the toy, or cause it to lift off the wall, pivoting about the front end. 
     The above embodiment is given by way of example only and various modifications may be made without departing from the scope of the invention. For example, the roller may be replaced by two or more rollers or wheels mounted on a common axle, each wheel having a simulated tyre of sticky material. Furthermore, the sticky material need only form the crests and could therefore take the form of discrete elements attached to a former in angularly spaced relationship. The sticky material could, moreover, be in the form of an adhesive coating or layer on a base of resilient plastics material and the plastics material could, for example, be in the form of an injection moulding rather than an extrusion.