Aerodynamic toy

An aerodynamic toy having a circular-shaped rotatable, free-flight body of generally convex/concave shape is provided. A downwardly extending rim portion integral with and forming a smooth continuous curve with the body acts in flight as a primary air foil. Spiral-shaped air spoilers are provided on the upper surface of the convex-shaped body.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates in general to an aerodynamic toy and, in particular, 
to such a toy of novel configuration, to be thrown by hand through the 
air. 
2. Description of the Prior Art 
Aerodynamic toys resembling so-called "flying saucers", and which are 
thrown by hand with a wrist-snapping action, have gained ever increasing 
popularity in the past several years. The wrist-snapping action imparts a 
spinning motion to the toy, as it flies through the air. The direction of 
flight from the thrower, in general, depends upon the thrower's skill, and 
the type of flight path (i.e., whether curved or straight) depends 
somewhat upon the angle of the aerodynamic toy in relation to the ground, 
when it is released by the thrower. These "flying saucers", or aerodynamic 
toys, fly as they do, i.e, when released approximately horizontal to the 
ground, apparently because they approximate an air foil. Hence, the toy's 
flight through the air is enhanced by aerodynamic lift. 
Various toys of this type have been developed over the past several years, 
and they have been enjoyed by the young, and the not-so-young, in 
backyards, in playgrounds, at the seashore, and other recreational areas. 
Exemplary of the prior art patents showing various of these aerodynamic 
toys are U.S. Pat. Nos. 2,659,178; Des. 183,626; Des. 241,565; 2,835,073; 
3,082,572; 3,359,678; 3,566,532; 3,710,505; 3,828,466; 3,948,523; 
3,724,122; 3,959,916; and 4,132,031. 
Probably the more successful of the aerodynamic toys is shown in U.S. Pat. 
No. 3,359,678. As disclosed in that patent, the aerodynamic toy, or 
"flying saucer", comprises a rotatable free-flight body of generally 
circular configuration having a generally convex upper surface, and a 
generally concave bottom surface terminating at and integral with a 
circular rim portion. Air flow spoiling means, a unique feature of that 
invention, are provided on the upper convex surface adjacent the rim 
portion which comprises a plurality of circular, raised ribs, concentric 
with the geometric center of the aerodynamic toy. 
In my earlier investigations, I discovered that the aerodynamic toy air 
spoilers need not necessarily be concentric, raised, ribs. The air 
spoilers, instead, can be radially extending, as disclosed in U.S. Pat. 
No. 4,132,031, which issued to me on Jan. 2, 1979. Although the radially 
extending air spoilers disclosed specifically in that patent are of 
somewhat limited configuration, there are disclosed other radially 
extending air spoilers of various configurations in my pending 
application, Ser. No. 959,995, filed Nov. 13, 1978, now U.S. Pat. No. 
4,216,611. Moreover, in that application, I disclosed that optionally the 
aerodynamic toy can be further provided with air spoilers located in a 
centrally disposed assembly. 
SUMMARY OF THE INVENTION 
Now, I have discovered that spiral-shaped air spoilers on the convex upper 
surface of the aerodynamic toy provide an aerodynamic toy of good flight 
stability and aerodynamic lift. 
Thus, there is provided in accordance with this invention, an aerodynamic 
toy comprising a rotatable free-flight body of generally circular 
configuration having a generally convex upper surface and a generally 
concave bottom surface, a downwardly extending rim portion integral with 
and defining the circumferential perimeter of the aerodynamic toy acting 
in flight as a primary air foil and at least one air spoiler having a 
spiral shape extending outwardly from centrally of the aerodynamic toy. 
In the more preferred embodiment of the invention disclosed herein, the 
aerodynamic toy comprises a plurality of spiral-shaped air spoilers, these 
being defined by the involutes of a portion of a fixed curve, more 
preferably that of alternating arcs of a centrally disposed concentric 
circle. Thus, there are provided a plurality of spiral-shaped air spoilers 
which may be raised above the convex upper surface of the aerodynamic toy 
or be inscribed as grooves, each two adjacent ones of which are separated 
by a flat portion of the convex body. 
While I do not wish, of course, to be limited to the explanation set forth 
herein, it appears that during flight, while the aerodynamic toy is 
rotating about its axis and is moving in a forward direction, air flow, at 
least in part, follows the path created by the spiral-shaped air spoilers. 
Thus, improved rotation of the aerodynamic toy results, and this in turn 
results in improved aerodynamic lift and flow of air over the upper convex 
surface.

DETAILED DESCRIPTION OF THE INVENTION AND THE PREFERRED EMBODIMENTS 
Referring to the drawings, there is shown in FIG. 1 thereof an aerodynamic 
toy 10 in accordance with the invention comprising a rotatable, 
free-flight body of circular configuration defined by rim portion 11, 
integral with a main body portion 12. As shown in the drawing, main body 
portion 12 is of a generally convex-concave shape, the underneath concave 
surface 13 of which is smooth and uninterrupted, except as hereinafter 
more fully described. 
On the upper convex surface 14 of aerodynamic toy 10 are provided a 
plurality of spiral-shaped, raised, air spoilers or elevations 15 which 
terminate, as shown, at rim portion 11. Between each two adjacent air 
spoilers 15, the convex surface 16 is smooth, thus providing alternating 
raised and flat surfaces. The spiral-shaped air spoilers 15 terminate at 
their inner ends at the circumference of a circular-shaped, depressed 
center portion 17. 
Spiral-shaped air spoilers 15, as will be appreciated, by reference to FIG. 
1, are defined by the involutes formed by successive 45.degree. arcs of a 
circle of predetermined diameter. Every other involute is raised in 
arcuate cross-section, as shown, above the convex upper surface 14 of the 
aerodynamic toy body 12. Thus, between each two adjacent raised spirals, 
or air spoilers 15, there is a flat spiral formed of an involute of the 
same width and shape as the raised one; or, if you prefer, between each 
two flat spirals, or involutes, there is a spiral in raised elevation. 
The involutes which define spiral-shaped air spoilers 15 can be, of course, 
of various widths, as desired, from that of essentially a point on the 
circle formed by depressed, circular center portion 17, to that, for 
example, defined by a 135.degree. arc. Dividing a circle into 360 
one-degree arcs will result in 360 involutes, providing 180 spiral-shaped 
elevations alternating with 180 spiral-shaped flat spaces. In the case of 
the embodiment shown in FIG. 1, circle 17 is divided into eight 45.degree. 
arcs. It will be found, however, that good performance will result when 
from one to nine raised involutes, or spiral-shaped elevations 15, are 
provided on the aerodynamic toy. Although in FIG. 3 of the drawing, 
spiral-shaped elevations 15 are seen to be of arcuate, or convex, 
cross-section, this need not necessarily be the case. These elevations can 
be of other cross-sectional configuration, for example, the leading, or 
outer, edge higher than the trailing edge with the elevation surface 
relatively flat and tapering downwardly from the leading edge to the 
trailing edge. 
The involutes need not be formed from equal arcs. For example, the 
perimeters of the raised elevations can be defined by involutes of arcs of 
greater or lesser degree than the involutes defining the spiral-shaped 
flat portion between the raised elevations. The raised elevations can be 
defined, by example, involutes of 45.degree. and the flat portions between 
adjacent raised elevations defined by involutes of arcs of 135.degree.. 
Only two raised spirals, in this case, would be formed, 180.degree. apart. 
Instead of involutes defining raised elevations, the involutes can, if 
desired, define spiral-shaped grooves inscribed in the upper convex 
surface 14. The involutes can, of course, although not shown in any of the 
figures of the drawing, be formed so as to spiral in the opposite 
directions. 
The spiral curves forming air spoilers 15 in FIG. 1 are defined, as shown, 
by the involutes of a circle; however, this need not necessarily be the 
case. Involutes can be formed from any fixed curve, e.g., polygons or 
circles as desired. The main thing is that the polygon be centrally 
disposed so as to be concentric to the geometric center of the aerodyamic 
toy. Thus, instead of a centrally disposed depressed circle, a depression 
of polygonal shape in cross-section could be provided. 
In FIG. 2 of the drawing, there is shown a slightly different embodiment of 
an aerodynamic toy 20 in accordance with the invention. The involutes in 
this case are of arcs of a circle 21 in the plane of the convex upper 
surface 14, concentric with the geometric center of the aerodynamic toy. 
Moreover, in this embodiment, contrary to that shown in FIG. 1, spiral 
shaped air spoilers 15 do not terminate at the juncture between rim 
portion 11 and convex/concave body 12. Instead, as shown, the involutes 
extend to the bottom of rim portion 11, thus providing further spoiling of 
the air than that provided generally by the primary air foil formed only 
by rim portion 11. Nevertheless, it will be appreciated that the 
spiral-shaped air spoilers 15 can be terminated at any point desired on 
the convex body. 
Turning now to FIG. 3 of the drawing, there is shown therein a diametric 
cross-section of still a further embodiment of an aerodynamic toy 30, 
according to the invention. In this embodiment, the spiral-shaped air 
spoilers 15 terminate at rim portion 11, as in FIG. 1. Central portion 31, 
however, is of a raised cylindrical configuration, the top planar surface 
of which is only slightly higher than the spiral shaped air spoilers at 
their inner end. Rim portion 11 of aerodynamic toy 30, as is the case with 
the aerodynamic toys 10, 20 shown in FIGS. 1 and 2, is provided integral 
with main body portion 2, and forms a downwardly turned smooth curve 
continuous with the generally convex upper surface 14. As indicated in the 
drawing, the outside surface 18 of rim portion 11 curves downwardly and 
somewhat inwardly, approximating the shape of a parabola opening inwardly 
toward the central axis of the saucer-shaped body of the aerodynamic toy 
30. 
The inner surface 19 of rim portion 11 can take the same curved shape as 
outer surface 18; however, in general, it is desirable not to provide this 
inner surface even though curved inwardly, parallel to outer surface 18. 
The rim portion 11 is desirably thicker than the main body portion 12, to 
provide a greater density in the rim portion. This makes for better 
stability of the aerodynamic toy, as it gives the toy direction, and 
sustains flight in the direction the toy was propelled. 
The inner surface 19 of rim portion 11 can, if desired, be in part curved, 
nearer the concave surface 13 of main body portion 12, and then flat. 
Thus, an approximately cylindrical-shaped inner surface 19 can be provided 
in rim portion 11, essentially concentric with the axis of the geometric 
center of the aerodynamic toy. In this manner, a rim portion 11 of 
substantial thickness can be provided, to provide in the larger diameter 
aerodynamic toy, particularly, a rim portion of much greater weight, when 
greater weight is desired. 
Aerodynamic toys in accordance with the invention can be manufactured 
readily by conventional molding techniques, e.g., injection molding, and 
from various plastic materials such as polyvinylchloride, polyethylene, 
polypropylene and the like. The plastic compositions can incorporate 
various of the conventional compounding agents to alter the physical 
properties of the plastic material, as desired, e.g., density, 
flexibility, hardness, etc. Coloring agents can be included to provide any 
suitable color or combination thereof, as desired. Quite desirably the 
spiral-shaped air spoilers will be of a contrasting color to the 
aerodynamic toy body. 
To facilitate manufacture, inner surface 19 can have a slight draft as 
shown. This will enable the aerodynamic toy to be more readily extracted 
from the mold. Also, it will be appreciated that, if desired, underneath 
concave surface 13 can be provided with concave spirals coincident with 
convex spiral-shaped air-spoilers 15 on convex body 12. This will not only 
result in some savings of materials of manufacture but also facilitate 
manufacture. 
It is, of course, desirable that the aerodynamic toy be of relatively light 
weight; however, it should not be so light as to adversely effect its 
performance. The optimum weight for any particular aerodynamic toy will 
depend somewhat upon its particular size, i.e., diameter. Where the 
spiral-shaped air spoilers are raised elevations, as shown in the figures 
of the drawing, this will, of course, add to the overall weight and 
thickness of the toy, and this should be taken into account. For example, 
where the aerodynamic toy is 10.5" in diameter, a weight of about 1.8 
grams/cubic inch volume displacement will be found satisfactory. In such 
an aerodynamic toy, the convex/concave body can be about 3/64" thick in 
the flat areas between the raised, spiral-shaped air spoilers. The 
aerodynamic toy in this case will have a thickness at the peak of an air 
spoiler of about 5/64". It will be appreciated that the drawings are 
somewhat exaggerated for sake of clarity. The spiral-shaped air spoilers 
shown in the drawings are convex in cross-section, and form a smooth curve 
with the flat areas between adjacent air spoilers. In this case, a center, 
circular portion of 17/8" diameter, defining involutes of 45.degree. arcs 
will be found satisfactory. If the spiral-shaped air spoilers are defined 
by grooved involutes, the thickness of the aerodynamic toy should, of 
course, be somewhat greater in the flat areas than indicated above. 
The depressed or raised center portion of the aerodynamic toy can be of a 
right cylindrical shape, rather than a truncated cone, as shown in FIG. 3. 
In the case of a depressed central portion, the sides can slope inwardly 
or outwardly, as desired. The depth of the depressed center portion can, 
of course, be varied, for example, from 1/16" to 1/2". When a raised 
central portion is provided, it desirably should not be substantially 
higher than the thickness of the spiral-shaped air spoilers. As in the 
case of the depressed center portion, however, the sides can be vertical 
or slope outwardly from top to bottom, e.g., at a 30.degree. angle with 
respect to the convex upper surface. The central circle can be, of course, 
of various diameters, as desired. The circle can even be merely a 
centrally located dot or circle of very small diameter. The smaller the 
diameter of the central circular portion, the longer will be, of course, 
the spiral-shaped air spoilers, and the tighter the spiral. 
In use, the aerodynamic toy of the invention is gripped by placing the 
thumb on the convex side of the toy and one or more of the fingers of the 
hand on the concave side. The toy is then thrown into the air with a twist 
of the wrist to give the aerodynamic toy a spinning impetus thereby 
causing it to rotate about its geometric center and to translate generally 
in the direction in which it is thrown. Throwing is accomplished in 
general by holding the aerodynamic toy horizontal to the ground. 
In practice, the spiral-shaped air spoilers appear to perform three 
functions: they distribute air flow over the convex upper surface; they 
act as secondary air foils while the aerodynamic toy is in rotary and 
lateral motion, and they also serve as air spoilers. Moreover, the central 
portion not only serves as a terminal point of the spiral-shaped air 
spoilers/foils, but also functions as a spoiler. 
As many different embodiments of this invention will now occur to those 
skilled in the art, it is to be understood that the specific embodiments 
of the invention as presented in this patent application are intended by 
way of illustration only and are not limiting on the invention, but that 
the limitations thereon should be determined only from the appended claims 
.