BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view looking at the bottom of a toy vehicle having a pivoting mechanism according to a first embodiment of the present invention.
FIG. 2 is a side elevation view of the toy vehicle of FIG. 1 with the front wheel shown in shadow to reveal the pivoting mechanism, showing the mechanism in the position it takes during forward travel of the vehicle.
FIG. 3 is a side elevation view of the toy vehicle of FIG. 1 with the front wheel shown in shadow to reveal the pivoting mechanism, showing the mechanism in the position it takes during reverse travel of the vehicle.
FIG. 4 is a simplified side elevation view of the inside of the right front wheel of the vehicle of FIG. 1 including the pivoting mechanism.
FIG. 5 is a simplified side elevation view of the inside of the right front wheel of a vehicle according to a second embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a perspective view of a first embodiment of a toy vehicle 10 having a pivoting mechanism according to a first embodiment of the present invention. The mechanism includes a rotating frictional element 20 co-axially located and adjacent to the inside of a wheel 12. Viewed from the underside of the body, the rotating element 20 rotates freely back and forth about wheel axle 26. Rotation is in accordance with the direction of motion over the travel surface. Herein, travel surface refers to any surface over which the vehicle travels. In a preferred embodiment rotating element 20 is not biased toward any particular rotation orientation.
Wheel 12 is depicted as a rim with a tire but could be any type of wheel. Wheel 12 has an outer peripheral surface 13 that contacts the travel surface. Rotating element 20 may be mounted on axle 26 with only an insubstantial amount of friction, which means the element rotates substantially freely about the axle. Axle rotation alone would not create sufficient friction by itself to consistently rotate the element about the axle. Alternatively, rotating element 20 may be mounted on axle 26 with enough friction that when vehicle 10 travels in the forward direction, rotating element 20 rotates up and off the travel surface as will be shown and explained further with reference to FIG. 2.
FIG. 2 is a side elevation view of the toy vehicle, with the front right wheel 12 shown in shadow to reveal details of the pivoting mechanism when the vehicle is moving in the forward direction. The molded plastic body of the vehicle includes two stops, namely, forward direction stop 24 and reverse direction stop 22. When the vehicle is moving in the forward direction as shown by the rotational direction arrow, rotating frictional element 20 rotates about vehicle axle 26 with enough friction to rotate the element up and out of the way against forward direction stop 24, but with not so much friction as to interfere with the free movement of the vehicle in the forward direction.
FIG. 3 shows the same elements as in FIG. 2, but with the vehicle shown traveling in the reverse direction as shown by the rotational direction arrow. Due to the slight friction of rotating frictional element 20 about axis 26, or simply due to gravity if there is little or no friction with axle 26, rotating frictional element 20 now rotates until its leading edge contacts the travel surface, then continues rotating downward as the vehicle continues moving backward until rotating element 20 rotates against reverse direction stop 22. In this position element 20, which has a radius slightly larger than the radius of wheel 12, lifts wheel 12 off the ground. The radius of element 20 is preferably 1-20% larger than the radius of the wheel, and more preferably 1-10% larger than the radius of the wheel. In one sense, element 20 jacks the vehicle up slightly at one wheel. Rotating frictional element 20 creates significant frictional contact with the travel surface such that when reverse power is applied, via either the front wheels or the rear wheels whichever are the driven wheels, vehicle 10 pivots at least somewhat about the area of contact between rotating frictional element 20 and the travel surface. If rotating frictional element 20 is made of a high friction material such as rubber, or has a high friction contact surface, the pivoting action will be pronounced. If, on the other hand, rotating frictional element 20 is made of a low friction material such as polyethylene or other plastic, and especially if the vehicle is traveling over a low friction surface such as a hardwood floor, rotating frictional element 20 will drag somewhat over the travel surface without creating as pronounced a pivoting action. The vehicle will, however, still turn even if there is only a relatively small amount of friction between element 20 and the travel surface.
In this embodiment, rotating element 20 rotates with the wheel associated about the wheel axle with sufficient friction such that rotating element 20 rotates about the axle for at least a portion of a revolution, until it bumps against first stop 22 in a first direction or against second stop 24 in a second direction.
FIG. 4 shows a side view of the embodiment of FIG. 2 looking from the vehicle side outward, but without the body element present. Adjacent to the inside 14 of wheel 12, rotating frictional element 20 is rotatably fixed upon axle 26 and maintains the approximate position shown when wheel rotation is in the forward direction when there is virtually no friction between element 20 and axle 26. The leading edge of contact surface 21 is located slightly behind the vertical centerline of the wheel. When the wheel rotates in the reverse direction, even a small amount of friction between contact surface 21 of rotating frictional element 20 and travel surface 30 will cause element 20 to rotate downward and lift wheel 12 off the ground.
Depending on design, the pivoting mechanism need not be located strictly adjacent to a wheel in order to perform and function. FIG. 5 depicts a second embodiment of the pivoting action mechanism, shown in a side view and without the vehicle for illustration purposes. Here, the pivoting mechanism is similar in size and shape, but is fixed to a secondary axle 140 other than the wheel axle, the secondary axle being located on an extension of the body of the vehicle or some other mechanism. Stop 122 is fixed to the extension of the vehicle body. The action and operation of the mechanism is the similar to that of the embodiment shown in the first embodiment, but an alternative mounting is utilized. When the direction of rotation is the reverse direction, the rotating element will rotate toward and up against stop 122, similar to as shown in the previous embodiment.
The scope of the design function of this mechanism is not necessarily limited to only the embodiments described herein, but may be applied to other designs as well. For example, an embodiment of similar design may control rotation of a wheel such that it becomes a point of contact with the travel surface about which the vehicle turns. That is, the wheel automatically locks in the reverse direction, and spins freely in the forward direction. The wheel itself therefore would serve the same function as the rotating element. As another example, the design of the body may integrate the stop into it in such a fashion that the stop and its function may not be recognized as a separate entity. In additional embodiments, the rotating element may limit maximum rotation by use of matched parts and shapes, or possibly by simple detents in the body, or by locating the stop on the rotating element itself.
The term “present invention” used herein should not be construed to refer to a single invention comprised of a single or multiple elements. As used herein the term encompasses a number of distinct embodiments of the same invention. Although the present invention has thus been described in detail with regard to the suggested embodiments and drawings thereof, it should be apparent to those skilled in the art that various adaptations and modifications of the present invention may be accomplished without departing from the spirit and the scope of the invention. Examples of this were detailed in the Summary above. Accordingly, it is to be understood that the detailed description and the accompanying drawings as set forth herein and above are not intended to limit the breadth of the present invention, which should be inferred only from the following claims and their appropriately construed legal equivalents.