BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the field of electrically powered toy vehicles, particularly in the form of toy race cars.
2. Prior Art
Electrically powered toy race cars are well known in the prior art. Such race cars take various forms and sizes. Of particular importance to the present invention are prior art race cars which are sold together with track sections which can be assembled into a race track for the cars. The track, of course, must have a size that is in proportion to the race cars themselves, and accordingly, to keep costs down there is an advantage in manufacturing and selling very small cars which in turn will use relatively small tracks.
Most electrically powered race cars utilize small rechargeable batteries together with an electric motor that somehow transfers rotary power to a set of wheels. In some electric toy race car designs the motor is mounted with its shaft parallel to an axle of the race car, with the shaft contacting the top of the tire on the respective wheel of the car to provide a friction drive thereto. Such a configuration has the advantage of simplicity, though it has certain disadvantages. In particular, such an arrangement tends to pick up floor debris such as lint, particles of dust and hair which accumulate on the tire and shaft of the motor, interfering with the operation of the drive system. Another disadvantage is the fact that if a solid axle is used to couple the drive wheel of the vehicle to the opposite wheel on the same axle, the diameter of the motor can become quite limited because of the required clearance between the motor and the axle. Further, placement of the motor shaft parallel to an axle shaft means that the length of the motor determines the width of the vehicle, which in turn requires a longer vehicle to maintain the proper vehicle proportions.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1a is a rear prospective view of a toy vehicle in accordance with the present invention.
FIG. 1b is a bottom view of the toy vehicle of FIG. 1a.
FIG. 1c is a top view of the toy vehicle of FIG. 1a.
FIG. 2 presents a front perspective exploded view of the toy vehicle of FIGS. 1a, 1b and 1c.
FIG. 3a is a perspective view of a complete axle assembly.
FIG. 3b is a cross section of the axle assembly of FIG. 3a taken through the centerline of the axle.
FIG. 4 is an exploded view of the entire toy vehicle.
FIGS. 5 and 6 illustrate the orientation of the motor and super capacitor within the toy vehicle of one embodiment.
FIG. 7 illustrates an alternate orientation of the motor within the toy vehicle.
FIG. 8 illustrates an alternate drive for the motor within the toy vehicle.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1a, 1b and 1c are a rear prospective view, a bottom view and a top view of the toy vehicle of one embodiment of the present invention. The toy vehicle is comprised of an upper body member 24, a lower body member 22 held together with screws 20, with wheels 36 with elastic tires 18 thereon. Also visible in these Figures are contacts 34 simulating a rear bumper of the toy vehicle, and wheels 36 with elastic tires 18 thereon. The upper body member 24 extends over the edges of the lower body member 22 so that no joint or gap between the upper body member 24 and the lower body member 22 is visible from either side or the front and back of the toy vehicle.
FIG. 2 presents a front perspective exploded view of the toy vehicle of FIGS. 1a, 1b and 1c. The vehicle consists of the lower body member 22, the upper body member 24, axle assemblies 26, super capacitor 28, motor 30 with a self-adhesive foam elastic member 32 coupled to an upper portion thereof, and finally, screws 20.
A super capacitor is a capacitor that has much greater energy density and power per pound than electrostatic and electrolytic capacitors. They are now well known to those skilled in the art. Of course, one could use a rechargeable battery in the toy vehicle of the invention, though a super capacitor is preferred because of its short recharge time and its ability to be continually recharged without loss of energy retention. In one embodiment of toy vehicle in accordance with the present invention, the recharge time is only a fraction of the run time achieved on a single charge. Also super capacitors of an appropriate physical size and capacity are readily commercially available, while because of the small size of the toy vehicle of one embodiment, rechargeable batteries of an appropriate phys al size are not readily commercially available.
The wheels 36 and tires 18 on the axle assemblies are shown in FIGS. 3a and 3b. FIG. 3a is a perspective view of a complete axle assembly, with FIG. 3b being a cross section thereof taken through the centerline of the axle 38. As shown in FIG. 3b, the axle 38 is connected to a wheel 36 at each end of the axle, preferably rigidly joined to the axle in such a way as to accurately define the spacing between the wheels, such as by way of example, by pressing the axles into the wheels, molding the wheels over the axles, or sonic welding the axles into the wheels. For this purpose, the axles used in the preferred embodiment have their ends formed so as to no longer be round to aide in the gripping of the wheels. As may be seen on FIGS. 3a and 3b, the tires have an integral raised annular area 40 positioned on the inside of the tire facing the opposite wheel. As shall subsequently be seen, this forms the friction drive surface for the motor shaft. In that regard, the two axle assemblies are identical, and the tires 18 can be removed from the wheels 36. Consequently, the tires may be rotated, so to speak, like on a full size vehicle in the event the raised area on the drive wheel tire becomes worn or damaged. Alternatively screws 20 (FIG. 1b) can be temporarily removed and the drive axle swapped end to end and/or the axles swapped front to back and back to front to achieve the same purpose.
FIG. 4 is an exploded view of the entire toy vehicle. As may be seen therein, the axles 38 snap into slots 42 in the lower body member 22. Alternatively, the axle assemblies could simply be captured between the lower body member 22 and upper body member 24, if desired. The motor 30 and super capacitor 28 are cradled between cradle projections on the upper body member 24 and the lower body member 22. The cradle projections 44 on the upper body member are visible in FIG. 4, with FIG. 2 illustrating the top of the lower body member and cradle member 46 therein. The self-adhesive foam elastic member 32 positively locates the motor with respect to the lower body member 22 for positive motor location with respect to the lower body member. Note that the leads of the motor are permanently attached (electrically connected) to the leads of the super capacitor, and the ends of the super capacitor leads are bent upward to form the contacts at the rear of the toy vehicle. In the charger used, the drive wheels are elevated by the charger body engaging the lower surface of the lower body member 22 so that the wheels can spin, thereby avoiding stalling the motor or slipping and burning of the contact between the motor shaft and the integral raised annular area 40 on the tire of the drive wheel as the super capacitor 28 is being charged.
Now referring to FIGS. 5 and 6, the orientation of the motor 30 and super capacitor 28 within the toy vehicle may be seen. In one embodiment, the motor 30 is inclined somewhat to provide road clearance, so to speak. This is not required for the super capacitor 28, as the entire supper capacitor may be somewhat elevated as desired. The motor however, should preferably have the axis of the motor shaft 48 pass through the axis of the axle of the wheel being driven by the motor. In the embodiment illustrated in FIGS. 5 and 6, the motor shaft 48 axis is also perpendicular to the axis of the drive axle 38, as shown in FIG. 6. This is not required however, as the motor axis may be inclined with respect to the drive wheel axis as illustrated in FIG. 7, particularly if the motor diameter would otherwise cause a bulge in the toy vehicle body. In any event, the force between the integral raised annular area 40 on the drive wheel and the motor shaft 48 moves the respective axle 38 as far one way as possible, the axle assembly being retained from further motion along its axis by the opposite wheel 36 rubbing against the lower body member 22. For this reason, it is preferred that the smallest diameter of the wheel be the part of the wheel rubbing against the lower body member 22. With this arrangement, it has been found that the friction of the drive system is not excessive, and that the motor alignment is set sufficiently accurately by design and without adjustment to achieve quite impressive performance on a single super capacitor charge.
A still further alternate embodiment for the motor drive is illustrated in FIG. 8. In this Figure, the shaft 48 of motor 30 has a sleeve 50 there over. The sleeve increases the effective diameter of the motor shaft and thus the speed of the toy vehicle. Also such a sleeve can be made of a plastic material having much higher friction with the tire, which in some instances could allow reduction in the contact force of the sleeve with the tire. Finally, such a sleeve also positions the motor more toward the fore and aft centerline of the toy vehicle, which could be advantageous if the motor diameter extended too far to the side of the vehicle.
An embodiment of the toy vehicle of the present invention is only approximately one inch long, and has the proportions of a real vehicle. The front wheel drive improves the stability of the toy vehicle, and packages easier, in that the inclination of the motor to provide bottom clearance increases the toy vehicle height toward the rear of the toy vehicle as in many full size vehicle designs. Also, placing the axis of the motor shaft lengthwise in the toy vehicle rather than crosswise saves vehicle width for the same motor size, and thus results in a smaller toy vehicle of appropriate toy vehicle length to width proportions for a given motor size. In one embodiment, the toy vehicles are in the form of race cars, and can be manufactured not only with different color schemes and decorations, but also with different body styles, as the body styles are determined exclusively by the upper body member 24.
Thus the present invention has a number of aspects, which aspects may be practiced alone or in various combinations or sub-combinations, as desired. While a preferred embodiment of the present invention has been disclosed and described herein for purposes of illustration and not for purposes of limitation, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the full breadth of the following claims.
Patent Grant
9440159
