Abstract:
A throwable or otherwise launchable aerial toy, which provides two relatively closely spaced colinearly aligned ring wings, with the forward ring wing being larger than the rear ring wing connected through a central slender member. The spokes connecting the rear ring wing to the central slender member can be configured in a fin shape to provide additional aerodynamic stability. The central slender member can be configured with a U-joint connection assembly to eliminate flight wobble due to manufacturing variations. The central slender member can also contain a rotating joint to permit the forward and rear wings or aerodynamic members to rotate independent of one another, separately or in combination with the U-joint connection in the same central slender member connection between the forward aerodynamic member assembly and the tail aerodynamic member assembly.

Description:
PRIOR APPLICATION 
     This application is a continuation-in-part application of provisional application Ser. No. 60/161,261 filed on Oct. 25, 1999 and claims priority from it. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to toys, in particular those which are hand thrown, or launched from a device using compressed air, springs, rubber band, or an electro-mechanical means. More particularly this invention relates to ring wing projectiles and more particularly to ring wing projectiles which are used as a sport toy device. 
     BACKGROUND OF THE INVENTION 
     There are a variety of flying toys. One group is similar to the American football, except that at one end of the football, a cylindrical rod-like boom extends rearward. Attached to the rear of the boom are a series of fins, which have a large surface area. These fins are intended to act as a stabilizer. One football shape with a rearward boom and fins is known under the trademark name “Vortex.” When thrown like a football, that is, with an initial spin or spiral motion about the flight direction and a forward or translational velocity, the large surface area fins produce high resistance to the rotational motion. In the technical field of ballistics this is known as spin decay or spin damping. Such spin damping readily reduces the gyroscopic stability, while the large, thick fins generate additional drag. 
     A more recent design variant of the Vortex flying football is the “Vortex Mega Spin.” This design allows the football-like fore-body to be thrown with spin, while the tail, which is connected through a rotatable coupling to the fore-body (axially fixed, but freely rotatable with respect to the football fore-body long axis), follows along substantially without spinning (considered to be a non-spinning tail). The non-spinning tail has lower drag than the tail of the original “Vortex” football. Nonetheless, both the fixed and non spinning tail designs of the “Vortex” variety footballs have fairly high aerodynamic drag. 
     A new “Vortex” product called the “Vortex Thunderjet” has recently come on the market. This new product is unlike the conventional “football” shape (see FIG.  1 ), in that it has a ring airfoil (or ring wing) as its main aerodynamic body (see FIG.  2 ). However, the new toy uses a set of conventional fins (see FIG. 2) to produce basic stability and directionality. The use of a ring wing is intended to produce lift and low drag, resulting in a flatter (non-ballistic) trajectory and extended range. That is, when properly thrown the new “Vortex Thunderjet” is intended to outperform, i.e., outrange, the conventional plastic football having conventional tail fins at the rear. The use of conventional tail fins at the rear often results in wobbling motion after the “Vortex Thunderjet” “football” is thrown. Wobble increases the drag and thus reduces the maximum range. The prior art designs suffer from the presence of elements which produce wobble and increase drag. It is desirable to produce a design to minimize wobble and drag so that optimum range based on a launched trajectory can be achieved. 
     SUMMARY OF THE INVENTION 
     A toy device according to the invention relates to a sport toy device which is hand thrown. This toy device could also be launched from an appropriately designed launcher using compressed air, spring force, rubber band force, or an electromechanical device. The toy device includes two ring wings. The two ring wings are connected to opposite ends of a relatively short center boom (central slender member). A diameter of a forward ring-wing is larger than a diameter of a rear ring wing. Further, the smaller diameter rear ring wing can contain fins within its inner diameter so as to provide additional flight stability to the toy device. The smaller diameter rear ring wing will be referred to as the tail ring wing, while the larger diameter front ring wing will be referred to as the main ring wing. 
     A device according to the invention achieves a relatively long range when thrown by hand, especially as compared to the current hand thrown sport toy football, advertised as the “Vortex.” The aerodynamic ring-wing shaping of a configuration according to the present invention develops lift from both wings along its flight path and, in combination with low drag, results in a relatively flat trajectory with extended range. The tail ring wing provides aerodynamic stability along its flight path, while having much lower drag than the conventional fins utilized on the Vortex football. A ring-wing device according to the present invention, produces less rotational resistance and excellent stability along its flight path axis, when the device is thrown or launched with initial spin, thus retaining more of the initial energy over the course of the flight path, than a similarly thrown prior art device. The two colinearly aligned wings substantially eliminate wobble and enhance flight stability which enables a hand thrown device according to the present invention to achieve longer range than a hand thrown “Vortex” configuration football, and to fly a longer distance than similarly sized prior art sport toy projectile devices. 
     Additional features and superior characteristics of the present invention will he better understood through the following detailed description in conjunction with the referenced figures. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of the prior art “Vortex” football; 
     FIG. 2 is a perspective view of the prior art “Vortex Thunderjet;” 
     FIG. 3 is a perspective view of a configuration according to the invention; 
     FIG. 4 is a sectional view of the configuration of FIG. 3 taken at A—A; 
     FIG. 5 is a sectional view of an alternate configuration according to the invention having a non-spinning ring-wing tail assembly; 
     FIG. 6 is a sectional view of an alternate configuration of the ring-wing tail assembly in combination with tail fins; 
     FIG. 7 is a sectional view of the tail design of FIG. 6 taken at B—B; 
     FIG. 8 is a partial cross-sectional cut-away view showing a hand gripping a configuration according to the invention, prior to throwing the device; 
     FIG. 9 is a close up exploded cross sectional view of an axial bearing connection for use in a configuration according to the invention; 
     FIG. 10 is similar to FIG. 9, except that the axial bearing is positioned in a first part of the connecting rod; 
     FIG. 11 is an assembled view of the items of FIG. 9; 
     FIG. 12 is a close up exploded cross sectional view of a U-joint connection for use in a configuration according to the invention; 
     FIG. 13 is an assembled view of the items of FIG. 12; 
     FIG. 14 shows the configuration of FIG. 13, but with a second end of the connecting rod offset by an angle through the U-joint connection; and 
     FIG. 15 shows a plan view of a U-joint of the type to be used in the configuration of FIGS.  12 - 14 . 
    
    
     DETAILED DESCRIPTION 
     A prior art throwing toy is shown in FIG.  1 . It consists of a plastic football shape  21  with a rod or boom (central slender member)  22  extending rearward from the plastic football  21 . Also extending rearward and attached to the boom  22  are a series of fixed fins  23  intended to stabilize the plastic football shape  21  in flight. However these large area and thick fins  23  add drag to the plastic football  21  thus requiring a significantly greater initial energy for the toy of FIG. 1 to achieve medium to long range/distance throws when compared to a conventional football. 
     Consequently, a subsequent prior art design replaced the conventional football shape  21  with a ring wing  24 , as shown in FIG.  2 . This design has an aerodynamic drag that is less than the drag of the configuration shown in FIG.  1 . With the reduced drag the configuration of FIG. 2 can more easily be thrown longer distances with the same initial energy when compared to the travel of the configuration of FIG.  1 . However a portion of the potential range is lost because of the drag due to thick fins  25 , their thickness is related to the amount of drag they produce, the greater the thickness the greater the drag. Furthermore , the fins act as spin dampers when the toy is thrown with an initial spin. Both elements reduce the efficiency of the design and bleed energy which thereby reduces the range of the throw. In contrast FIG. 3 is a perspective view of a configuration according to the invention. 
     The configuration shown in FIG. 3 consists of two ring wings  24  and  28 , a larger diameter ring  24  (approximately 4″ in diameter) serving as the main ring wing, while a smaller diameter ring wing  28  (approximately 3″ in diameter) acts as a tail stabilizer. The ratio of the diameter of the tail ring wing to the diameter of the main ring wing can be approximately 0.8:1, 0.75:1, 0.6:1, or 0.5:1. 
     The main ring and tail stabilizer are connected by a central slender body member (having a nominal diameter of ⅝ inches). The distance between the trailing edge of the main ring wing and the leading edge of the tail ring wing can be a selected ratio of the diameter of the main wing, such as 3:1, 2:1, and 1.5:1. 
     FIG. 4 shows a cross sectional view of the configuration of FIG.  3 . If necessary, the struts or streamlined supports  30  shown in FIGS. 4 and 5 can be replaced by internal fins (e.g.,  36 , radiating outward along a radius line from the central axis) as shown in FIG. 6, so as to provide more stability in flight. The main ring wing  24  is composed of a foam rubber or spongy plastic and dimensioned such that it can be readily grasped and thrown like a football. The diameter of the rear or tail ring wing  28  (approximately 3″) is smaller than the diameter of the main ring wing  24  (approximately 4″) so that during the act of throwing there is no interference between the throwing hand and the toy during the toy&#39;s release. The main ring wing  24  is separated from the rear ring wing  28 , by a center member length of approximately 4 inches, (separation distances can reasonably be as large as 10″ and as small as a distance approximately equal to the diameter of the main ring wing). 
     The configuration shown in FIG. 5 is similar in overall design to the configuration shown in FIG. 4 except that the tail ring wing  28  is decoupled from any spin experienced by the main ring wing  24  by means of a bearing assembly (the location of which is shown inside the circle  32 ). The bearing assembly is located closer to the tail ring wing  28  than to the main ring wing  24 . Improved flight stability results from decoupling the tail ring wing  28  from the main ring wing  24 . The decoupling eliminates the dynamic response or rotational motion of the ring-wing tail  28  from influencing the overall motion of the entire unit so that there is minimum disturbance during the flight trajectory of the entire unit. In other words the use of a bearing assembly as shown in circle  32  or similar rotational connection, allows the entire unit to have excellent stability during the flight when thrown or launched by other means. Further, the high lift/low drag aerodynamic characteristics of the entire unit enables the unit when thrown or launched by other means to reach record distances. 
     FIG. 6 is a design variant of the tail assembly containing items  28  and  30  in FIGS. 3-5. Should it be necessary to increase the flight stability without a major increase in either the length of the center body (stem)  34  rearward and/or increasing the diameter of the tail ring wing  28 , aerodynamically shaped fins  36  can replace the original struts  30 , within the inner diameter of the ring-wing tail  28 . The increased surface area of the fins  36  will greatly increase the stability in pitch and yaw thereby assisting in a more accurate flight path. The number size and area of the fins  36  located inside the tail ring wing  28  may be best determined by iterative testing. This methodology may also be used to obtain the optimal fin geometry (e.g., sweepback angle of the fins, their number, and area). 
     The exterior surface of the larger ring wing may also have a series of longitudinal grooves to aid gripping by a throwers fingers as shown in FIG.  8 . Appropriate weights may be placed within the large ring wing to give the toy sufficient total weight and balance or by selecting materials depending on their density, to achieve a similar effect. 
     FIG. 9 shows a cross sectional exploded arrangement of a stem (center body) bearing connection. Either end can be leading or following. The center body material is expected to be constructed of a stiff but not brittle plastic material. A bearing receiving cavity  40  exists in a first  42  of the members. The cavity  40  includes a bearing retaining lip  44  and a central void  46 . When a bearing  50  is inserted the lip  44  expands and snaps down to hold the bearing  50  in place. A second piece  60 , has a small central stem  62  with a barb shaped element  64  on its end that passes through a central passage (axis)  52  of the bearing  50  and snaps in to hold the second piece  60  in connection with the first piece  42 . The first piece  42  can then rotate freely with respect to the second piece  60 , but their axial positions are substantially fixed by the axial position snap fit. 
     An alternate configuration which can be used together with or alone separate from the rotational bearing configuration shown in FIGS. 9-11, is a U-Joint connection configuration shown in FIGS. 12-14. A third end  70  (to distinguish its identification from the first and second ends pictured in FIGS. 9-11, though it could be one of those) can be connected to either the main or rear wing portions of the device. A U-joint cross  80 , is snapped into two sets of clamping fingers  72 ,  74 , and  92 ,  94  disposed at 90° to one another. An overhanging outside sleeve or skirt  76 , prevents the third  70  and fourth  90  members from having a misalignment greater than approximately 5°, without hitting the skirt  76 , which acts as a stop. The use of a U-joint connection can further enhance aerodynamic streamlining, by providing a mechanism by which dimensional variations introduced in manufacturing are negated. For example, if the main wing&#39;s central axis is not perfectly aligned with the rear wing&#39;s central axis, then additional drag is created due to the difference in the angle of attack between the two wings. In the instance when a U-joint connection is provided (either separately or in conjunction with the previously described bearing connection) the aerodynamic forces due to misalignment between the central axis of the two members will create a restoring force, which moves the U-joint to balance the aerodynamic forces to reduce the misalignment and associated drag, to create a longer flight. 
     The U-joint. connection and U-joint and bearing combination connection can also be used with a fin tail of the type shown for FIG.  1 . 
     While the invention has been described with specific embodiments, those skilled in the art will recognize that changes can be made in form and detail without departing from the spirit and the scope of the invention.