US3715833A

US3715833A - Glider toy

Info

Publication number: US3715833A
Application number: US00179939A
Authority: US
Inventors: R Nickerson; J Economos
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-09-13
Filing date: 1971-09-13
Publication date: 1973-02-13
Anticipated expiration: 1990-02-13

Abstract

A glider toy is provided having at least one longitudinally extending planar fin and a planar annulus perpendicular to the fin. The annulus is bilaterally symmetrical with respect to its median longitudinal plane.

Description

United States Patent Nickerson et al.

[ 1 GLIDER TOY [75] Inventors: Robert J. Nickerson, Forest Park;

James N. Economos, Evergreen Park, both of I11.

[73] Assignee: Nickerson, Economos and Noonan, Evergreen Park, Ill.

[22] Filed: Sept. 13, 1971 [21] Appl. No.1 179,939

[52] US. Cl. ..46/79, 46/74 D, 273/106 B [51] Int. Cl. ..A63h 27/00 [58] Field of Search ..46/79, 74; 273/106 B [56] References Cited UNITED STATES PATENTS 3,590,518 7/1971 Le Baron ..273/106 B X [15] 3,715,833 [451 Feb. 13, 1973 D 1 62,707 4/1951 Benson ..46/79 X Primary Examiner--Louis G. Mancene Assistant Examiner-D. L. Weinhold Attorney-Roger M. Fitz-gerald [5 7] ABSTRACT A glider toy is provided having at least one longitu dinally extending planar fin and a planar annulus perpendicular to the fin. The annulus is bilaterally symmetrical with respect to its median longitudinal plane.

10 Claims, 8 Drawing Figures PATENTEDF i975 SHEET 1, OF 2 FIG.|

PATENTED FEB 1 3' 1913 3 715 833 sum 2 or 2 GLIDER TOY This invention relates generally to glider toys and, more specifically, to an improved glider toy having an annular combined wing and stabilizer.

Glider toys in general are designed to superfically resemble powered aircraft or manned Sailplanes.

Hence they often have relatively massive fuselage portions which reduce the distance and duration of their glides. Both types of manned aircraft are provided with controlled movable surfaces for longitudinal and lateral control of the aircraft. In glider toys, on the other hand, the configuration of the craft is fixed. The gliding or soaring path is a product of the interaction of this fixed configuration with the launch path and wind currents encountered in flight. Hence merely patterning glider toys after manned aircraft does not produce optimum results in terms of the distance or duration of glides.

Accordingly it is an object of the present invention to provide a glider toy with a configuration which will minimize the difficulties encountered as a result of simply emulating the configurations of manned aircraft with massive fuselage portions and movable control units.

Another object of the invention is to provide a glider toy which is inherently stable in flight.

Still another object of the invention is to provide a glider toy in which the lifting surface and the longitudinally stabilizing surfaces are combined in a single structure having a simple geometric shape.

Yet another object of the invention is to provide a glider toy which may be conveniently launched in a normal or in an inverted position.

A further object of the invention is to provide an operative glider toy formed completely of flat pieces without the necessity of conventional airfoil shaping or cambering.

A still further object of the invention is to provide a glider toy which may be easily constructed and assembled with a minimum of waste materials.

Other objects and advantages of the invention will become apparent from the following description and the accompanying drawings in which:

FIG. 1 is a force diagram illustrating the forces acting on a glider toy in flight.

FIG. 2 is a side view of a glider in flight partially broken away to show the centers of area and gravity of a glider toy in accordance with the invention.

FIG. 3 is a top plan view of the glider toy of FIG. 2.

FIG. 4 is a side view of the glider toy of FIG. 3 taken along lines 4--4.

FIG. 5 is a top plan view of another glider toy showing various features of the invention.

FIG. 6 is a side view of the glider toy of FIG. 5 taken along lines 6-6.

FIG. 7 is a top plan view of still another glider toy showing various features of the invention.

FIG. 8 is a side view of the glider toy of FIG. 7 taken along lines 88.

As shown in FIG. 1 there are two significant forces acting on a glider: the weight of the glider designated by the vector arrow W and the aerodynamic force designated by the vector arrow A. The aerodynamic force comprises a lift component perpendicular to the glide path and a drag component along the glide path. The weight may be resolved into a thrust component along the glide path and a component perpendicular to the glide path. In gliding this latter component is counterbalanced by the lift component of the aerodynamic force. The length of the glide path of a glider and the duration of its flight is dependent upon the ratio of drag to lift. Accordingly glider performance is improved if the drag is smaller for a given lift, i.e. the gliding angle G is minimized and the flight path is increased. I

In powered aircraft additional thrust is provided by the propulsive units. In such aircraft and in manned Sailplanes fuselages are essential and drag and lift may be controlled by the adjustment of movable surfaces such as ailerons, elevators and elevons. Such expedients are impractical in glider toys, and glider toys which are merely patterned after their manned counterparts naturally are deficient in performance. The present invention obviates many of these problems by providing a fixed configuration in which proper gliding attitude is ordinarily automatically maintained and, if disturbed, is automatically corrected, and in which drag is minimized, thus improving flight performance.

As show-n in all of FIGS. 2 through 8 a glider toy embodying features of the invention generally includes a vertical longitudinally extending planar fin 10 to provide lateral stabilization of the glider in flight. The glider also includes a planar member 12 in the form of an annulus with a central opening which is horizontal or perpendicular to the fin 10. (The terms vertical and horizontal are used herein to refer to the orientation of the glider when not in flight. It should be apparent that such orientation may and will vary in flight and that the use of such terms is not to be construed to limit the invention.) The annulus is bilaterally symmetrical with respectto the median longitudinal plane of the annulus.

The annular member includes a forward portion 16 and a rearward portion 18 which, as illustrated, are symmetrical to one another with respect to a vertical transverse plane so that the center of area of the annulus is at the center of the annulus on the transverse plane. The annulus serves the dual functions of providing lift as does a wing and providing longitudinalor pitch stabilization by means of its rearward portion 18.

The forward portion 16 includes a frontal portion 20 which extends forwardly of the fin 10 to define the nose of the glider. Attached to the frontal portion 20 of the annulus is a weight 22. As illustrated, the weight is in the form of a J-shaped clip which engages the top and bottom of the annulus after the annulus is inserted into the open end of the clip. The clip is so constructed that most of its mass is onthe one leg of the J which is positioned below the annulus.

The vertical fin 10 extends from the rearward portion 18 of the annulus at least partially into the central opening of the annulus 12 thus providing a means for grasping the glider during launch and eliminating the need for heavy fuselage elements. The positioning of the fin at least partially within the opening permits the glider to be launched, if desired, from an inverted position since the fin can easily be grasped from above or below the annulus.

The fin 10 and annulus 12 are desirably constructed of easily fabricated light weight materials of sufficient strength to withstand repeated landing impacts such as balsa wood. The weight 22 on the other hand, is

preferably made of light metal or wire. As shown in FIG. 2, it is of importance that the relative weights and dimensions of the components be such that the center of gravity (CG) of the entire glider be in front of the lateral center of area of the annular member (CAL). This arrangement, illustrated in FIG. 2, causes the glider in flight to automatically maintain the desired nose down gliding attitude. Indeed it is desirable, as also illustrated in FIG. 2, that the weights and dimensions be such that the center of gravity of the entire glider be below the frontal portion 16 of the annular member as also shown in FIG. 2. Such an extreme positioning will cause the glider to pull out of a steep dive despite the fact that the annular member is not shaped or cambered like a conventional airfoil, since the greater nosing down characteristic will automatically correct for a too steep glide path in the same manner as does a pilot of a manned plane. It is also desirable, as shown in FIG. 2, that the vertical fin 10 be so shaped and positioned that its center of area (CAV) is behind the center of area (CAL) of the laterally extending annulus. In such case if the nose of the glider diverges laterally, the areodynamic force on the tin will be corrective.

In practice it has been determined that a desirable range for the ratio of the average radius of the opening in the annular member to the width of each side of the annular member is between about two to one and four to'one. Also in practice it has been determined that the area of the fin should be at least about one eighth of the area of the annular member.

In the embodiment shown in FIGS. 2-4 the fin 10 is in the form of an isosceles triangle with its apex toward the front of the glider and is positioned almost entirely within a circular opening of a symmetrican annular member 12 having a circular outer circumference. This fin has equal areas above and below the annulus. Thus the conditions stated above as to the positions of the centers of lateral and vertical area are easily satisfied. The ratio of the radius of the opening in the annular member to the width of each side of the annular member is about two to one in this embodiment.

In FIGS. 5 and 6 another embodiment is shown in which the annular member 12 also is circular on both its inner and outer circumference. The fin is semicircular and is positioned with most of its area above the annulus. In this embodiment the fin extends only partially into the annular opening from the rear portion of the annulus to insure that the lateral area center is behind the vertical area center. This embodiment is extremely easy to fabricate since the fin may be formed from the cut out section of the annular member. The ratio of the radius of the opening of the annular member to the width of each side of the annular member is about four to one in this embodiment.

In FIGS. 7 and 8 the annulus 12 has an elliptical outer circumference and an elliptical inner circumference. The fin 10 is also elliptical and may be formed from the cut out portion of the annular member but is mounted with its center of area slightly behind the center of area of the annulus and in the plane of the annulus by means of top and bottom struts 24. In this embodiment additional fins 26 are provided symmetrically positioned with respect to the median plane of the annulus. It should be apparent that the additional tins could provide sufficient lateral stabilization and that the central fin 10 could be eliminated in some embodiments.

It will be apparent that many advantages are provided in the disclosed glider. The glider essentially lacks a drag producing fuselage thus greatly improving performance. All of the components function either to provide lateral or longitudinal stability or lift or to maintain or correct gliding attitude. The combination of lifting surfaces and longitudinal stabilizing surfaces in the annular member simplifies fabrication and assembly. The positioning of the fin at least partially within the opening of the annulus provides an easy means for grasping the glider for launch and even permits launching in an inverted position. Due to the minimal drag the annular member provides sufficient lift despite its lack of a conventional airfoil shape. However, airfoil shaping could be used without departing from the invention.

Various changes and modifications may be made in the invention without departing therefrom. For example, the glider assembly could be manufactured in completely assembled form, prefabricated elements of the assembly could be manufactured and sold, or materials together with patterns for the assembly elements could be sold. Various materials could be used in constructing the glider toy, the annular member and fin could be made in various shapes and additional stabilizing surfaces could be added, all of which would fall within the scope of the claims appended hereto.

What is claimed is:

1. A glider toy comprising at least one longitudinally extending planar fin and a planar annular member perpendicular to said fin and bilaterallysymmetrical with respect to the median longitudinal plane of said annular member.

2. A glider toy according to claim 1 wherein said planar annular memberhas a forward portion to provide lift and a rearward portion to provide longitudinal stabilization.

3. A glider toy according to claim 1 wherein the center of gravity of the glider is in front of the center of area of said annular member.

4. A glider toy according to claim 1 wherein the center of gravity of the glider is below said annular member.

5. A glider toy according to claim 1 wherein said annular member has a frontal portion in front of said fin defining the nose of the glider and the center of gravity of the glider is below said frontal portion.

6. A glider toy according to claim 1 wherein the center of area of said annular member is in front of the center of area of said fin.

7. A glider toy according to claim 1 including a weight member adjacent the front of said annular member. 7

8. A glider toy according to claim 1 wherein said fin is positioned at least partially within the opening of said annular member.

9. A glider toy assembly comprising at least one longitudinally extending planar fin to provide lateral stabilization, a planar annular member perpendicular to said fin and bilaterally symmetrical with respect to the median longitudinal plane of said annular member, said annular member having a forward portion to provide lift and a rearward portion to provide longitudinal stabilization, and a weight member adjacent to the front of said annular member with its center of mass below said annular member, said fin extending at least partially into the opening of said annular member from the rearward portion of said annular member to facilitate grasping of said fin, the center of gravity of said assembly being below and in front of the center of area of said annular member and the center of area of said an-

Claims

1. A glider toy comprising at least one longitudinally extending planar fin and a planar annular member perpendicular to said fin and bilaterally symmetrical with respect to the median longitudinal plane of said annular member.

2. A glider toy according to claim 1 wherein said planar annular member has a forward portion to provide lift and a rearward portion to provide longitudinal stabilization.

7. A glider toy according to claim 1 including a weight member adjacent the front of said annular member.

9. A glider toy assembly comprising at least one longitudinally extending planar fin to provide lateral stabilization, a planar annular member perpendicular to said fin and bilaterally symmetrical with respect to the median longitudinal plane of said annular member, said annular member having a forward portion to provide lift and a rearward portion to provide longitudinal stabilization, and a weight member adjacent to the front of said annular member with its center of mass below said annular member, said fin extending at least partially into the opening of said annular member from the rearward portion of said annular member to facilitate grasping of said fin, the center of gravity of said assembly being below and in front of the center of area of said annular member and the center of area of said annular member being in front of the center of area of said fin.