MODEL FLYING VEHICLE WITH SMOOTH LANDING

Abstract: Disclosed is a model flying vehicle, such as a model heli­ copter, wherein the main wing (2) returns from the slanting po­ sition (that is, pitched) to the flat position (that is, zero pitch) when the power is disengaged, thereby ensuring stable and smooth landing without impact or damage to the flying body or the wing.

Description: This invention relates to a model flying vehicle, and more particularly to a model flying vehicle with a configuration for stabilization of the vehicle during landing. Model flying vehicles especially helicopter toys are given a sufficient force of lift to take off through a source of power such as a twisted rubber coil. However, special and careful attention has not been paid to the landing mechanism of such vehicles. The conventional vehicle descends while the elevation angle of the main wings remains the same as that during take-off, and the vehicle will therefore land in an unstable state (that is, at an angle with respect to the ground) and in some cases the flying body will whirl several times prior to landing. It is, therefore, highly likely that the flying body will be subject to a large impact during landing and that the flying body, the main wings or the tail wings will be damaged. US-A-2 931 132 discloses a model flying vehicle in which the angle of elevation of the wings varies according to the action of centrifugal forces due to their speed of rotation. The model vehicle disclosed relies on the rotor being freely rotatable after the vehicle has been given an initial upward thrust, and does not include a built-in power source. According to the invention there is provided a model flying vehicle structure comprising: a flying body; a spindle portion rotatably mounted on said flying body; wing means secured to said spindle portion for rotation therewith, said wing means comprising two blade portions; a shaft extending through said spindle portion; an axially movable cap member on said shaft arranged to be selectively engageable with said spindle portion; spring means disposed between said spindle portion and said cap member for normally biasing said cap member out of engagement with said spindle portion; an elastic member operatively connected to said flying body and said shaft for engaging said cap member with said spindle portion to provide a force of rotation to said spindle portion and said wing means for elevating said flying body by lift produced by said rotating wing means; and projections disposed on one side of each blade portion for selective engagement with said cap member; wherein manually rotating said wing means relative to said flying body twists said elastic member to provide stored energy for rotating said spindle portion and said wing means and displaces said cap member into engagement with said spindle portion and to act on said projections on said wing means to increase the elevation angle of said wing means relative to said flying body so that when said stored energy is released said wing means lift said flying body in flight, said spring means subsequently acting to disengage said cap member from said spindle portion and said projections on the wing means to allow free rotation of said wing means and a decrease in the elevation angle of said wing means to stabilize the flying body during landing and permit it to land without significant impact. In particular, when the source of power is disenabled, the elevation angle of the wing means may be reduced into a zero (a flat state), permitting the flying body to descend naturally only due to its gravity and with a high degree of stability as if it floats in the sky. This avoids the objectionable situation where the flying body bumps against the ground with a large impact and the flying body or the wing means become damaged or battered. In order that the present invention may be better understood a detailed description of an embodiment thereof will be given, by way of example, and with reference to the accompanying drawings wherein: Fig. 1 is a side view of a flying vehicle according to the present invention; Fig. 2 is an exploded perspective of the flying vehicle shown in Fig. 1; and Fig. 3 is a cross sectional view of a shaft assembly in the flying vehicle of Figs. 1 and 2. Figs. 4(a) to 4(d) show how to assemble a main wing in the flying vehicle as shown in Figs. 1 and 2. In Figs. 1 and 2, there are illustrated a side view and exploded perspective view of a flying vehicle, a helicopter toy, according to an embodiment of the present invention. The flying vehicle generally comprises a flying body 1, a main wing 2, a tail wing 3, a power source 4 such as twisted rubber and a leg 5. The majority of the flying vehicle, except for a few components, is made of a plastic molding and designed in shape and weight so that it may easily be given the force of lift. As best shown in Fig. 2, the main wing 2 has a pair of blades 11, 11 each having a projection 13, 13 in the vicinity of the periphery of a spindle portion 12. The main wing 2 is made of plastic molding as described above, which molding is so flexible that its elevation angle is easily variable. The spindle portion 12 of the main wing 2 is molded separately from the blade portions 11, 11 and shaped into a cylinder with a pair of engaging pawls 14, 14 at its top. Then, the blade portions 11, 11 and the spindle portion 12 are jointed into a single unit through the use of joints 15, 15. Disposed over the main wing 2 is a cap member 16 which has on its base a pair of openings 17, 17 for receiving the engaging pawls 14, 14 therein. The stem portion of the cap member 16 is also adapted to receive a spring 18 therein. The rubber coil of the power source 4 is secured in the following manner. While the spring 18 is inserted into the stem portion of the cap member 16 and a pair of spacers 19, 19 are secured above and below the spindle portion 12 of the main wing 2, a shaft 20 is positioned to pass through the center of the spindle portion 12 and the cap member 16 with its upper end engaging into the cap member 16 and a hook at its lower end extending into a stud 21 at the center of the flying body 1. The rubber coil is wound between the hooked lower end of the shaft 20 and the leg 5. Fig. 3 depicts in more detail the shaft 20 secured in the above manner. To make the vehicle take off, the operator places the engaging pawls 14, 14 into alignment with the openings 17, 17 in the cap member 16 and winds up the rubber coil by rotating the main wing 2 while holding the body 1. As the rubber coil is wound, the main wing 2 is forced down together with the cap member 16 by the force of the twisted rubber coil against the spring 18. Because of the projections on the cap member 16 being in contact with the counterparts 13, 13 on the main wing 1, the periphery of the projections on the blade portions are pushed down to provide the main wing with a given elevation angle. When the operator releases his hand from the main body after windup of the rubber coil the flying body 1 is given thrust by the rubber coil 4 and lift by the elevation angle of the main wing, thus starting take-off. When this occurs, the pawls 14, 14 of the spindle portion 12 are kept in engagement with the openings 17, 17 in the cap member 16 so that the flying body 2 can keep ascending due to the proper elevation angle of the main wing 2. If the rubber coil is fully unwound or the power source is disengaged, the flying body 1 loses the thrust and starts descending. Under these circumstances, the rubber coil has no pulling power so that the spring 18 acts to lift the cap member 16 and disengage the pawls 14, 14 of the spindle portion 12 from the openings 17, 17 in the cap member 17. Upon such disengagement, there is nothing that pushes down the projections 13, 13, so that the blade portions 11, 11 of the main wing resume a flat state due to its flexibility. The result is that the whole of the flying vehicle descends naturally only due to its gravity while keeping a stable flying position in the sky. There is no likelihood of the flying body losing balance or abruptly whirling during landing. The impact on the flying body during landing is reduced to a minimum, whereby damage to the vehicle is prevented. Figs. 4(a) to 4(d) illustrates how to assemble the main wing 2. As described above, the main wing 2 comprises the spindle portion 12 and the blade portions 11 both molded separately from each other. It is clear from Fig. 4(a) that the spindle portion 12 further has an insert 27 with a stop 22 at a higher level and a stay 23 with a pair of openings 24, 24 at a lower level. The blade portion 11, on the other hand, further includes a curved groove 25 and a pair of projections 26, 26 which are to be received within the respective openings 24, 24 in the stay 23. First of all, the blade portion 11 is placed topside down, with the curved groove receiving the insert 27 of the spindle portion 12. At this moment, the stop 22 extends out of the groove 25 so that the blade portion 11 is prevented from separating from the spindle portion 12. Then, the blade portion 11 is turned by 180 degrees as indicated in Fig. 4(b) so as to place the projections 26, 26 into alignment with the openings 24, 24. Finally, the tip of the stay 23 (that is, the openings) are tightly secured into the projections 26, 26. It is important to note that the stay 23 itself is flexible and forces the blade portion 11 to a flat position when the power source is disenabled or when the pawls 14, 14 of the spindle portion 12 are disengaged from the openings 17, 17 in the cap member 17. Another important function of the stay 23 is to keep the blade portion 11 from erecting in a vertical direction. As stated above, according to the present invention, the main wing returns from the slanting position (that is, with a proper elevation angle) to the flat position when the power is disengaged, thereby ensuring stable and smooth landing without impact or damage to the flying body or the wing.

Claims: A model flying vehicle structure comprising: a flying body (1); a spindle portion (12) rotatably mounted on said flying body (1); wing means (2) secured to said spindle portion (12) for rotation therewith, said wing means (2) comprising two blade portions (11); a shaft (20) extending through said spindle portion (12); an axially movable cap member (16) on said shaft (20) arranged to be selectively engageable with said spindle portion (12); spring means (18) disposed between said spindle portion (12) and said cap member (16) for normally biasing said cap member (16) out of engagement with said spindle portion (12); an elastic member (4) operatively connected to said flying body (1) and said shaft (20) for engaging said cap member (16) with said spindle portion (12) to provide a force of rotation to said spindle portion (12) and said wing means (2) for elevating said flying body (1) by lift produced by said rotating wing means (2); and projections (13) disposed on one side of each blade portion (11) for selective engagement with said cap member 16; wherein manually rotating said wing means (2) relative to said flying body (1) twists said elastic member (4) to provide stored energy for rotating said spindle portion (12) and said wing means (2) and displaces said cap member (16) into engagement with said spindle portion (12) and to act on said projections (13) on said wing means (2) to increase the elevation angle of said wing means (2) relative to said flying body (1) so that when said stored energy is released said wing means (2) lift said flying body (1) in flight, said spring means (18) subsequently acting to disengage said cap member (16) from said spindle portion (12) and said projections (13) on the wing means (2) to allow free rotation of said wing means (2) and a decrease in the elevation angle of said wing means (2) to stabilize the flying body (1) during landing and permit it to land without significant impact. A model flying vehicle according to claim 1, wherein said wing means (2) are normally not engaged by said cap member (16) except when said elastic member (4) is sufficiently rotated to overcome the force exerted by said spring means (18). A model flying vehicle according to claim 1 or claim 2, wherein said spindle portion (12) includes outwardly projecting inserts (27) and said wing means (2) includes curved grooves (25) affixed thereto, said curved grooves (25) being mounted on said inserts (21) to restrict relative rotation between said wing means (2) and said spindle portion (12). A model flying vehicle according to any preceding claim further including a stay (23) affixed to each of said blade portions (11) and to said spindle portion (12) the stays (23) acting to restore the position of said wing means (2) relative to said spindle portion (12) after said cap member (16) is disengaged from said projections (13) on said wing means (2). A model flying vehicle according to claim 4, wherein said stays (23) are flexible and force said wing means (2) to a predetermined angular relationship relative to said spindle portion (12). A model flying vehicle according to any preceding claim further including a first spacer (19) disposed between said spindle portion (12) and said flying body (1) and a second spacer (19) disposed between said spindle portion (12) and said cap member (16). A model flying vehicle according to any preceding claim further including engaging pawls (14) affixed to said spindle portion (12) and projecting toward said cap member (16), and flanges projecting outwardly from said cap member (16) said flanges including openings (17) for engaging said engaging pawls (14) to position the flanges for engagement with said projections (13) on said wing means (2). A model flying vehicle according to any preceding claim, wherein said flying body (1) is a helicopter and said wing means (2) are rotors. A model flying vehicle according to any preceding claim, wherein said elastic member (4) is a rubber band. A model flying vehicle according to any preceding claim wherein said wing means are made of plastic molding and are flexible to enable the variation of elevation angle.

Inventors: UEDA, KOSAKU
Applicants: UEDA, KOSAKU
Application year: 1985
Main classification: A63H27
IPC codes: A63H27