Background of the Invention With the development of miniature and relatively low cost electronic components, various systems for remotely controlling toy vehicles became commercially attractive and feasible. Notsurprisingly, the introduction into the marketplace of small self- powered remotely controlled toy vehicles was greeted with great commercial success. Perhaps the most prevalent type of remotely controlled toy vehicle is that type which generally resembles an automobile, truck or other similar wheeled vehicle. While substantial variation of system design exists among remote controlled vehicles, basically all utilize a battery-powered toy vehicle having a signal receiver which controls the steering and drive power of the toy vehicle. A remote control transmitter usually held by the operator is capable of transmitting the required signals to the vehicle's control system to allow the user to manipulate controls on the transmitter and observe a corresponding response by the toy vehicle.

While various energies have been used in controlling such remotely controlled vehicles, the most prevalent systems use radio-frequency signals. Additionally, such systems have employed infrared and ultrasound energies as communication mechanisms between the handheld controller and the remotely controlled vehicle.

In a continuing attempt to improve the market for such toy vehicles, a variety of different devices have been provided. For example, the remotely controlling systems themselves have been substantially developed to increase the transmitting power and reliability thereby improving the operative range of the toy vehicle. The toy vehicles themselves have been the subject of substantial improvement as better batteries and electric drive motors have improved the vehicle capability. In still other areas of development, the operative controls have been simplified and the overall cost of the system has been driven down.

U. S. Patent 3,590,526 issued to Deyerl sets forth a REMOTELY STEERABLE VEHICLE illustrative of early development of self-powered remotely controlled toy vehicles. The vehicle set forth therein utilizes a pair of drive motors individually coupled to the vehicle rear wheels to provide differential drive which simultaneously serves the functions of moving the vehicle and turning or steering the vehicle. The front suspension of the vehicle is passive and utilizes a pair of pivotally supported swing arms each having a half axle secured thereto which in turn supports a front wheel. A transverse link is pivotally secured to the half axles to couple the

front wheels together. During turning, the parallelogram formed by the two front pivots and the pivots of the transverse link cause the front wheels to move in response to vehicle turning.

US Patent 4,183,174 issued to Barris, et al. sets forth a TOY STUNT VEHICLE having a motor driven rear wheel and a free wheeling rear wheel. The vehicle is capable of performing a wheel stand while moving circularly.

US Patent 4,197,672 issued to Mabuchi, et al. sets forth a MODEL RACING CAR having front wheels, rear wheels, drive motors and a radio control receiver adapted to control a front wheel drive mechanism.

US Patent 4,213,270 issued to Oda sets forth a RADIO CONTROL WHEELED TOY having a pair of front wheels and a pair of rear wheels rotatably supported upon a common chassis. A pair of drive motors are coupled to drive gears on diametrically opposite front and rear wheels of the vehicle.

US Patent 4,596,534 issued to Ishimoto sets forth a REMOTELY STEERED TOY CAR WITH FIVE WHEELS having front and rear wheels together with a fifth powered wheel. The fifth powered wheel is centered between the freely rolling rear wheels.

US Patent 4,666,420 issued to Nagano sets forth a TOY CAR OF A FRONT WHEEL DRIVING TYPE having front wheels for driving and changing direction. The toy vehicles includes a chassis and a lifting rod connected to the chassis for supporting a rear axle.

The car also includes a hinge for pivotally securing the lifting rod to allow the lifting rod to move away from or toward the chassis.

US Patent 4,810,229 issued to Shoji sets forth an OMNI DIRECTIONAL TOY VEHICLE having a quartet of dual wheels positioned at the four corners of a toy vehicle. The individual dual wheels are separately steerable through a gear coupling mechanism to provide steering action of all four dual wheels.

US Patent 4,892,503 issued to Kumazawa sets forth an ACTION TOY VEHICLE WITH CONTROLLABLE AUXILIARY WHEEL having a plurality of road wheels rotatably suspended from a vehicle chassis and an auxiliary wheel mounted on a structure which can be selectively lowered and steered in response to a remote control signal.

US Patent 5,019,009 issued to Chao-Chin, et al. sets forth a TOY CAR CHASSIS INTERMITTENT TILT AND STEERING STRUCTURE having a lift wheel lever extending from the underside of the car chassis for periodically raising one side of the chassis as the motor drives the car.

US Patent 5,135,427 issued to Suto, et al. sets forth a CATERPILLAR TYPE TOY VEHICLE having a body and chassis together with a pair of endless belt tracks for providing propulsion.

US Patent 5,261,853 issued to Suto sets forth a TOY VEHICLE WITH STEERABLE FRONT WHEELS AND CATERPILLARS having a body and chassis supported by a

pair of front wheels and a pair of rear endless belt track drive units.

US Patent 5,281,184 issued to Suimon sets forth a STEERING DEVICE FOR AUTOMOTIVE TOY VEHICLE having a pair of pivotally supported front wheels coupled to a transverse steering arm. The steering arm is further coupled to a rotatable rack and pinion gear mechanism which in turn is driven by a steering motor.

US Patent 5,312,288 issued to Williams sets forth a STEERING SYSTEM FOR TOY VEHICLE having a simplified steering system wherein an elongate member rotates with the vehicle cab and causes the front wheels to move to a location such that the vehicle will turn in the desired direction as the cab is tilted.

US Patent 5,338,247 issued to Miles sets forth a BATTERY-POWERED MODEL CAR having a straight rear axle and a nonindependent rear suspension. The vehicle includes a chassis having a central longitudinal axis with a centrally located battery pack. A pair of remotely steerable wheels are pivotally affixed to the chassis front end.

US Patent 5,429,543 issued to Tilbor, et al. sets forth a VEHICLE TOY having a pair of freely movable front wheels and a quartet of rear wheels coupled to a differential drive mechanism.

US Patent 5,449,311 issued to Williams sets forth a STEERING SYSTEM FOR TOY VEHICLES which steers the vehicle front wheels in response to tilting of the vehicle body.

While the foregoing described prior art devices have improved in the art and, in some instances enjoyed commercial success, they are often overly complex and therefore undesirably costly and unreliable. There remains, therefore, a need in the art for a simplified system of toy vehicle steering which avoids the complexity, cost and unreliability associated with prior art systems.

Summary of the System Accordingly, it is a general object of the present invention to provide an improved remotely controlled toy vehicle. It is a more particular object of the present invention to provide an improved remotely controlled toy vehicle having a simplified front end steering system which minimizes the number of parts and costs of manufacture.

In accordance with the present invention, there is provided a remotely controlled toy vehicle comprising: a chassis having a front and a rear; a pair of rear wheels supported by the chassis at the rear; a differential drive apparatus coupled to the pair of rear wheels; a steering caster having a pair of front wheels and a forwardly extending center frame; and a pivot pivotally coupling the caster frame to the front of the chassis such that the front wheels are supported rearwardly of the pivot.

Brief Description of the Drawings The features of the present invention, which are believed to be novel, are set forth with particularity in the appended claims. The invention, together with further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings, in the several figures of which like reference numerals identify like elements and in which: Figure 1 sets forth a perspective view of a toy vehicle constructed in accordance with the present invention; Figure 2 sets forth a partial section view of the rear differential drive mechanism of the present invention toy vehicle; and Figure 3 sets forth a partial front end view of the present invention toy vehicle having the body removed from the chassis to expose the common caster front steering of the invention.

Description of the Preferred Embodiment Figure 1 sets forth a side perspective view of a remotely controlled toy vehicle constructed in accordance with the present invention and generally referenced by numeral 10. Toy vehicle 10 includes a body 11 supported upon a chassis 16 (the latter seen in Figures 2 and 3 below. Toy vehicle 10 also includes a pair of rear wheels 12 and 13 and a pair of front wheels 14 and 15. Body 11 is shown styled to

provide a fanciful race car appearance. However, it will be understood by those skilled in the art that the present invention toy vehicle may be fabricated using a variety of toy vehicle bodies having different appearances and aesthetic characteristics without departing from the spirit and scope of the present invention. By means set forth below in Figures 2 and 3 in greater detail, toy figure 10 is powered by an internally supported differential drive system coupled to rear wheels 12 and 13. The differential power coupling to wheels 12 and 13 facilitates the propulsion and steering action of the toy vehicle. In further accordance with the present invention and as is also set forth below in greater detail, front wheels 14 and 15 are pivotally supported by a common caster front steering apparatus. This apparatus facilitates the caster-like front steering of the present invention toy vehicle without resorting to the previously utilized complex systems which require four pivotal attachments and joints in the steering system.

As will be seen below in particular in reference to Figure 3, the steering apparatus of the present invention utilizes a simple common caster and single pivotal attachment to provide front steering operation.

Figure 2 sets forth a partial section view of toy vehicle 10 taken along section lines 2-2 in Figure 1.

To avoid unduly cluttering the drawing figure, body 11 is not shown in Figures 2 and 3. Toy vehicle 10 includes a supporting chassis 16 having a motor housing 20 formed therein. Housing 20 defines an interior 21 having a pair of vertically oriented spaced apart interior walls 30 and 31. Chassis 16

further includes a pair of integrally formed axle supports 22 and 24. Axle support 22 defines an axle bore 23 while axle support 24 defines an axle bore 25.

Vehicle 10 further includes a rear wheel 13 having a half axle 32 secured thereto. Half axle 32 passes through axle bore 23 and is received within an aperture 34 formed in interior wall 30. Similarly, toy vehicle 10 includes a rear wheel 12 secured to a half axle 33 which extends through axle bore 25 and aperture 35 formed in interior wall 31. A pair of drive gears 46 and 49 are secured to the interior portions of half axles 32 and 33 respectively. Thus, the combined structures of wheel 13, half axle 32 and gear 46 and wheel 12, axle 33 and gear 49 are each independently rotatably supported by chassis 16.

Motor housing 20 further supports a pair of electric motors 40 and 42 having respective output shafts 41 and 43. Output shaft 41 supports a drive gear 44 coupled to an intermediate gear 45 which in turn engages gear 46. Similarly, output shaft 43 supports a drive gear 47 coupled to an intermediate gear 48 which in turn engages gear 49. Thus motors 40 and 42 independently drive wheels 13 and 12 respectively through their respective gear trains to rotate half axles 32 and 33. Because of the independent drive capability to each wheel, the drive apparatus is referred to as a"differential drive".

This differential drive capability is well known in the art and facilitates rotating rear wheels 12 and 13 independently or at different speeds to produce steering and propulsion of toy vehicle 10. As is better seen in Figure 3, toy vehicle 10 further includes an electronic control module 26 and a

plurality of conventional batteries 27 and 28 all supported upon chassis 16. Control module 26 functions in accordance with conventional fabrication techniques to provide controlled energizing of motors 40 and 42 in response to control signals received by vehicle 10 from a remote control transceiver (not shown). Batteries 27 and 28 provide operative power for motors 40 and 42 in accordance with conventional fabrication techniques. Thus, it will be understood by those skilled in the art that the differential drive apparatus and remote control apparatus of toy vehicle 10 may be fabricated in accordance with conventional fabrication techniques. The essential feature of the differential control drive and remote control apparatus of vehicle 10 is the ability of the vehicle to respond to remotely transmitted control signals which operate to differentially apply power to rear wheels 12 and 13 which in turn produces turning and propulsion of the present invention toy vehicle.

Figure 3 sets forth a partial top view of toy vehicle 10 having body 11 removed. In accordance with the present invention, the front suspension of toy vehicle 10 is shown in solid-line representation in a straight line travel while a dashed-line representation illustrates the response of the steering system to a turning action.

More specifically, toy vehicle 10 includes a chassis 16 which supports body 11 (seen in Figure 1) in accordance with conventional fabrication techniques. Chassis 16 includes a motor housing 20 which, as is set forth above in Figure 2, supports the dual motor differential drive apparatus of the toy

vehicle. In addition, motor housing 20 supports a plurality of batteries 27 and 28 together with a remote control module 26. Batteries 27 and 28 and remote control module 26 are operatively coupled to the differential drive motors of the present invention toy vehicle in accordance with conventional fabrication techniques (not shown).

Chassis 16 further defines a front pivot 50. In accordance with the present invention, toy vehicle 10 further includes a steering caster 51 pivotally secured to chassis 16 by pivot 50. Steering caster 51 includes a generally V-shaped caster frame 52 extending rearwardly from pivot 50 and joined to a pair of outwardly extending axle supports 53 and 54.

In the preferred fabrication of the present invention, caster frame 52 and axle supports 53 and 54 are formed of an integral one piece unit such as a molded plastic component or the like. The essential function of steering caster 51 is the support of front wheels 14 and 15 in a rearward position from pivot 50. This rearward position provides the caster-like steering action of the present invention toy vehicle.

In response to turning action of toy vehicle 10, the caster-like action of steering caster 51 responds to produce a corresponding pivotal movement of the entire steering caster and front wheels 14 and 15.

For example, in the event toy vehicle 10 is commanded to execute a left turn, the front end portion of vehicle 10 is steered to the left in the direction indicated by arrow 60. As chassis 16 rotates or turns in the direction indicated by arrow 16, the combined operation of steering caster 51 and pivot 50 cause the

entire steering caster to pivot about pivot 50 in the directions indicated by arrows 61 and 62. As the turning continues, the combined structure of steering caster 51 and front wheels 14 and 15 moves to the dotted-line position shown in Figure 3.

Once vehicle 10 reassumes a straight line travel, the combined structure of steering caster 51 and front wheels 14 and 15 returns to the solid-line position shown in Figure 3. It will be apparent that a turn of vehicle 10 in the opposite direction (a right turn) moves pivot 50 in the opposite direction of arrow 60 causing the combined structure of steering caster 51 and front wheels 14 and 15 to pivot in the opposite direction to arrows 61 and 62.

Unlike prior art devices which utilize a plurality of pivotal elements to accomplish a caster- like steering function, the present invention structure utilizes a single pivot and an integral steering caster supporting both front wheels to provide steering operation without the undue cost and complexity of prior art devices.

In addition, it has been found that the pivoting action of the integral steering caster supporting both wheels produces a novel appearance as the outer wheel of the turning radius is pivoted forwardly of the chassis and the interwheel is pivoted rearwardly.

This appearance adds a heightened amusement and entertainment value to the present invention toy vehicle which is not obtained with independently castered front wheels as utilized in the prior art.

In essence, the appearance is that of a"power slide"

often referred to in racing circles as a four wheel drift during cornering or steering. This effect has been found to be extremely entertaining and amusing to the child user. Thus, the present invention toy vehicle accomplishes steering in a simple and inexpensive manner while adding an additional appearance and performance characteristic not realized in more complex and expensive steering systems.

While particular embodiments of the invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects. Therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention.