US2870568A - Model airplane - Google Patents

Description

Jan. 27, 1959 H. A. BEl QGSTRAND MODEL AIRPLANE 2 Sheets- Sheet 1 Filed March 18, 1957 v INVENTOR H. A.. BERGSTRAND ATTORNEY Jan. 27, 1959 H. A. BERGSTRAND 2,8

7 MODEL AIRPLANE! Filed March 18, 1957 2 Sheets-Sheet 2 FIG. I3

v INVENTOR. H. A. BERGSTRAND I ATTORNEY United States Patent MODEL AIRPLANE Harold A. Bergstrand, East Moline, 11L, assignor to Strombeck-Becker Manufacturing Co., Moline, 11]., a corporation of Illinois Application March 18, 1957, Serial No. 646,812

' 12 Claims. (Cl. 46-76) This invention relates to a toy or model airplane and more particularly to improvements in wing and elevator structure.

The invention features novelty and simplicity in construction through the use of composite and bracing structure enabling the exploitation of sheet material as the basic material of which the ship is constructed, to the end that the ship may be furnished in kit form for assembly into a model that is attractive as a display item as well as having good flight characteristics and resistance to damage in crashes. In a preferred embodiment, the ship is constructed primarily of sheet material such as polystyrene, which itself has certain structural advantages in addition to its ability to lend itself to mass production methods as well as being economical, light in weight, attractive and easy to cement, but which also has certain structural disadvantages where the sheet portions are of substantial area. Therefore, it is a feature of the invention to utilize tubular or hollow'structure to enhance the strength of the material.

and an improved wing assembly having in addition to such mounting a double-thickness portion at least adjacent to the fuselage and strut-receiving pockets in the wing assemblies and fuselage; and such other features and objects, inherent in and encompassed by the invention, as will appear from the ensuing detailed description Figure 6 is an enlarged section on the line 6--6 of Figure 1.

Figure 7 is an exploded view based on Figure 6.

Figure 8 is a perspective of the underside of the base wing.

Figure 9 is an enlarged section on the line 9-9 of Figure 2.

Figure 10 is a view on the line 1010 of Figure 9.

Figure 11 is an enlarged exploded perspective of the landing gear support.

Figure 12 is an enlarged section on the line 12--12 of Figure 9.

Figure 13 is an enlarged section on the line 13-13 of Figure 9.

The ship as it appears in Figure 1 has much the general appearance of a conventional airplane, actually being a scale model to a major extent of a well-known full-sized model whose identity is of no moment here. As such, it has a fuselage 20, right and left wing assemblies 22,

and tail assembly 24 including right and left elevators 26 and a rudder or fin 28. The fuselage is tubular, here shown as made up of right and left complementary halves It is a primary object to provide a novel wing and/ or elevator mounting.

2,870,568 Patented Jan. 27, 1959 appropriately flanged to be cemented or otherwise secured together along a joint 30 that lies in tne upright foreand-aft median plane of the ship. The tubular character of the fuselage results from its formation of formed sheet material, one suitable type of which is polystyrene, which may be commercially vacuum-formed. The designation here of this material and/or its forming process. does not of course exclude others, but that referred to has been selected because of its accepted use in production of planes of the nature described.

The fuselage thus has an under or belly portion 32 which provides a pair of opposite generally upright foreand-aft side walls 34. Since these are symmetrical at both sides of the median plane along the joint 30 and are further symmetrical relative to components to be described, the ship will be further dealt with as from one side only, thus avoiding repetition.

In the formation of the fuselage halves, each side Wall is provided with a fore-and-aft elongated exterior mounting pad 36 of airfoil shape as seen in elevation, and this pad thus has an outer mounting surface 38 defined by an upper convex edge 40 and a lower straight edge 42. This surface along the lower edge 42 is spaced laterally outwardly fro-m the fuselage side wall 34 to provide a fore-and-aft downwardly facing and inwardly and downwardly sloping ledge or lip 43 (Figures 2 and 7). The elevators 26 are mounted via similar pads, one of which appears at 44 and which, having the configuration and other characteristics just outlined need not be further described. Each elevator pad 44 mounts its Wing-like elevator element 26, which is of sheet-like construction, having here a single-thickness concavo-convex top wall 46extending outwardly from a generally upright foreand-aft wall 48 which has an airfoil shape conforming to that 'of the pad 44. Thus when the elevator is to be assembled to its pad, the inner surface of the elevator wall 48 is coated with suitable adhesive, such as any well known cement, and is placed congruently with the pad and thus secured thereto. The concave-convex section of the elevator top wall conforms generally to the upper edge of the airfoil shape of the pad. The pad 44, like the wing-mounting pad 36, has its lower edge spaced outwardly from the proximate side of the fuselage to afford a fore-and-aft inwardly sloping and downwardly facing ledge 50 exactly like that at 43, and the elevator mounting wall has along its lower edge a cooperative flange 52 which projects inwardly below and is cemented to the ledge, thus materially adding to the cementing area and consequently improving the strength of the joint. Moreover, since the mounting wall is generally upright to the top wall 46, it maintains the concavoconvex shape of that top wall and affords an airfoil? section to the elevator. In a commercial embodiment of the ship disclosed, the various components are vacuumformed in a single sheet and are cut out therefrom for assembly. The flange 52 results simply from leaving the necessary amount of sheet on the end wall 48.

Each wing assembly 22 is of particularly novel design and construction and comprises a Wing stub 54 and a base wing 56, the latter being materially longer than the former and including an inward portion 58 and an outward portion 60, integrally formedfrom the polystyrene sheet, for example. The stub 54 overlies the inward portion 58 of the base wing and the two are generally congruent in this area, although in contact only about their marginal edge portions, as will presently appear, because of differences in cross-section. The stub has an inner fore-and-aft, here upright, inner end mounting wall 62 of airfoil shape so as to be substantially congruent with the mounting pad 38 when assembled, and this wall thus has a convex upper edge 64 and a straight lower edge 66 and aer sea a top wall sheet which is here of single thickness and of concave-convex section conforming to the convex upper edge As in the case of the elevator 26, the mounting wall 62 maintains the airfoil shape of the stub, which, in addition to the inner end at 62, has a free outer end 70 and leading and trailing lateral edges 72 and 74 respectively.

When the stub and base wing are assembled, the stub lies on top of and is generally congruent with the inward portion 53 of the base wing, the latter having an inner fore-and-aft end 76 and front and rear or leading and trailing edges 78 and 80 respectively. The inner end 76 lies along the inner end wall lower edge 66 of the inner stub wall 62 and in that area the base wing is of generally section. Since the stub top wall sheet 68 in this area is concavo-convex, the two will be vertically spaced apart. However, the base wing gradually changes section and at an intermediate portion 82 assumes a concave-convex section conforming generally to that of the stub at its outer end 70, whence the base wing continues into its outward portion and retains its concavo-convex section in that outward portion to achieve an airfoil section, the maintenance of which results from the construction and assembly of the stub and base wing as will be described immediately below. tated otherwise, the wing 22 is of tubular section at its inner part (Figure 3), is of double thickness in the zone 82 (Figure 4) and is of single thickness in its outward part (Figure 5).

The stub mounting wall 62, like the wall 48 of the ele vator 26, has along its lower edge a marginal flange 84 which projects laterally inwardly under and is secured to the lip or ledge 53 of the wing pad 36, this flange being achieved in the manner and serving the purpose and function already covered with respect to the elevator mounting. In the preferred assembly shown, the inner end 76 of the base wing is downwardly offset to afford an integral fl nge 77 which underlies and is secured to the under side of the stub flange 84, thus assuring the flat section of the base wing in the area noted. In addition. the stub 54 and base wing inward portion 58 are secured together at their respective leading and trailing ed es 72-78 and 74-450 and the two are further cemented or otherwise secured together in t e base wing intermediate zone 82 to afford the double-thickness part as shown in Fi ure 4. Hence. when viewed in Figure 6, the stub 54 and base win inward portion 53 converge out ardly and meet in the zone 82, and the outward portion 60 extends of course beyond that zone. Adiacent to this zone, the base wing is formed with a vertical offset to afford a fore-and-aft shoulder 86 of a depth commensurate with the thickness of the stub top wall sheet 68 and this shoulder receives the outer end of the stub top wall so that the upper surfaces of the stub and base wing outward portion are generally flush.

The inward portion 5% of the base wing is formed or recessed to provide, just inwardly of'the zone 82. a downwardly facing strut-receiving pocket 88 which. because of the nature of the sheet material is also reflected at the upper surface of the base wing; but. since this pocket is covered by the proximate sheet portion 68 of the stub 54, it is concealed from above. Hence, although the formation of the pocket 8'3 is in trumental in improving the construction. particularly adding strength to the structure adiacent to the zone it is concealed as stated above and therefore does not detract from the authenticity of the model. A tubular strut 90 has its outer or upper end received in and cemented to the pocket 88 and has its inner or lower end received in and cemented to the fuselage via a fuselage pocket 9?. integrally formed in the fuselage wall 34. The strut is preferably made up of a pair of complementary halves cemented together and having web portions 94 and 96 respectively overlapping the edges of the pocket structures and 92., with the adjacent rounded portions of the strut actually entering the pockets. The

pockets are an aid in assembling the components as well as contributing to the maintenance of the respective joints.

A further feature of novelty is the landing gear mounting, which here takes the form of a pair of wire elements 98. Since these are symmetrical, only one and its mounting will be described. The wire has a strut or leg 100 which is arranged herein downwardly and outwardly inclined relation to the median plane of the ship and this leg terminates at its lower or outer end as an integral transverse axle 102 for journaling a landing wheel 104. The leg 100 has at its upper or inner end a portion 106 in the form of an L made up of a transverse part 108 and a fore-and-aft part 110. In keeping with the concealment of components and joints likely to detract from the authenticity of the model, the fuselage wall 34 is apertured at 112 to receive the wire 98, so that the leg 100 is external to and the L 106 is interiorly of the wall. The wall has a slight transverse curvature and the L part 108 conforms thereto. The fore-and-aft part of the L lies along the fuselage and the L portion is secured to the interior surface of this fuselage by means in the form of an L-shaped member 114 having an L-shaped groove 116 therein to receive the L-shaped part of the wire. Again cement is used as the adhesive, since the material of the member 114 and that of the fuselage may be the same. The transverse part 108 of the L restrains the leg against lateral displacement and the fore-and-aft part 110 performs the same function relative to fore-and-aft displacement. In order to avoid the necessity of producing rights and lofts, the wires for the two sides of the ship may be identical and when assembled, the fore-and-aft part of one extends forwardly and the other rearwardly, and the members 114 are identical but are rotated as respects each other when assembled. In addition to securing and confining the wire-Ls 106, the two members operate as a cross brace in the belly section of the fuselage. v The leg of the wire 98 is concealed by a tubular strut housing 118, preferably made up of a pair of complementary halves cemented together and forming a housing that embraces the wire. An intermediate portion of the leg is of zig-zag configuration as at 101 (Figure 11) and its fore-and-aft disposition within the housing (Figures 9 and 13) prevents the housing from turning about the axis of the wire leg 100. Thus, the actual support of the landing gear is via the wires, and the strut housings, although carried by the wires, do not interfere with the flexibility thereof.

Another instance of the exploitation of wire as a stifiener is shown at 29 in the fin or rudder 28 (Figures 1 and 2).

The objects and general nature of the improvements wrought here have been elaborated along with the description. Features and objects not so enumerated will readily occur to those versed in the art, as will many modifications and alterations in the preferred inventive embodiment disclosed, all of which may be achieved without departure from the spirit and scope of the invention.

What is claimed is:

1. A toy airplane, comprising: a fuseleage having a fore-and-aft generally upright side wall; a fore-and-aft mounting pad on and exteriorly of said wall and having an outer mounting face of airfoil shape defined by a convex upper edge and a substantially straight lower edge, said face along said lower edge being spaced outwardly from said side wall to afford a fore-and-aft downwardly facing ledge; a stub wing of sheet construction having inner and outer fore-and-aft ends, leading and trailing edges and being of concavo-convex section from front to rear so as to conform substantially to the convex upper edge of the pad face, said stub at its said inner end having a generally upright wall depending from said concavoconvex section and shaped to lie substantially congruently against and secured to said pad face, said stub wall having a lower fore-and-aft flange integral therewith and projecting under and secured to the, pad ledge; and-a base wing of sheet construction having an inward portion below and generally congruent with the stub and an outward portion projecting laterally outwardly beyond the outer end of said stub, said base wing in its inward portion having leading and trailing edges secured respectively to the leading and trailing edges of the stub, and an inner edge secured to the stub flange, said base wing having an intermediate portion under and secured to the outer end of the stub, and said base wing being of substantially fiat section at its said inner edge and changing to a concave-convex section at said intermediate portion to generally conform to the section of the stub at the outer end of the stub, whereby the stub and inward portion of the base wing are spaced vertically apart adjacent to the mounting pad and converge to and meet at the junction of the outer end of the stub and said intermediate portion of the base wing.

2. The invention defined in claim 1, in which: said base wing in its intermediate portion is vertically offset to afford a fore-and-aft shoulder of a depth commensurate with the thickness of the stub sheet and receiving said stub outer end so that the upper surfaces of the stub and the outward portion of the base wing are substantially flush at the junction therebetween.

3. The invention defined in claim 1, in which: the base wing includes in its inward portion an upwardly recessed part affording a downwardly opening pocket laterally outwardly of the fuselage and concealed from above by the overlying stub; and a strut has one end received in said pocket and extends downwardly and inwardly to an inner end proximate and secured to the fuselage.

4. The invention defined in claim 3, in which: th fuselage side wall has therein an outwardly and upwardly facing pocket receiving the inner end of the strut.

5. A toy airplane, comprising: a fuselage having a fore-and-aft generally upright side wall; a stub wing of sheet construction having inner and outer fore-and-aft ends, leading and trailing edges and being of concavoconvex section from front to rear and having at said inner end a generally upright wall depending from said concave-convex section and lying proximate to the fuselage side wall, said stub wall having a lower fore-and-aft straight edge and an upper convex edge joined to said concave-convex section; means securing the stub wall to the fuselage side wall; and a base wing of sheet construction having an inward portion below and generally congruent with the stub and an outward portion projecting laterally outwardly beyond the outer end of said stub, said base wing in its inward portion having leading and trailing edges secured respectively to the leading and trailing edges of the stub, and an inner edge secured to the wall lower edge, said base wing having an intermediate portion under and secured to the outer end of the stub, and said base wing being of substantially flat section at its said inner edge and changing to a concaveconvex section at said intermediate portion to generally conform to the section of the stub at the outer end of the stub, whereby the stub and inward portion of the base wing are spaced vertically apart adjacent to the fuselage and converge to and meet at the junction of the outer end of the stub and said intermediate portion of the base wing.

6. The invention defined in claim 5, in which: said base wing in its intermediate portion is vertically offset to afford a fore-and-aft shoulder of a depth commensurate with the thickness of the stub sheet and receiving said stub outer end so that the upper surfaces of the stub and the outward portion of the base wing are substantially flush at the junction therebetween.

7. The invention defined in claim 5, in which: the base wing includes in its inward portion an upwardly recessed said pocket and extends downwardly and inwardly to an inner end proximate and secured to the fuselage.

8. A toy airplane, comprising: a fuselage having a fore-and-aft side wall; a fore-and-aft elongated mounting pad on and exteriorly of said wall and being of generally airfoil shape, having an outer generally upright mounting face defined by an upper convex edge and a lower straight edge, said face along its lower edge being spaced laterally outwardly of said wall to afford a fore-and-aft down- 1 wardly facing ledge; and a wing-like element having an inner generally upright mounting face substantially congruent with and having face-to-face contact with and secured to the pad face and like said pad face having an upper convex edge and a lower straight edge, said element having along its lower edge a fore-and-aft flange projecting laterally inwardly under and secured to the pad ledge.

9. The invention defined in claim 8, in which the element is of sheet-like construction of concave-convex section conforming generally to the upper convex edge of the pad, said element mounting face comprises a depending wall integral with said element and said flange is integral with the lower edge of said element wall.

10. In a toy airplane having a fuselage, a wing assembly comprising: a wing stub having a fore-and-aft inner end mounting wall of airfoil shape including an upper convex edge and a lower straight edge, said stub including a top wall sheet of concave-convex section joined to and extending laterally outwardly from said convex upper edge of said inner end wall to a fore-and-aft outer end and said top wall having leading and trailing edges; and a base wing sheet having an inward portion substantially congruent with and underlying the stuband an outward portion extending laterally outwardly be- -yond the outer end of the stub, said inward portion having leading and trailing edges secured respectively to the leading and trailing edges of the stub and an inner fore-and-aft edge lying along the lower edge of the inner end wall of the stub, said base wing sheet further having an intermediate portion underlying and secured to the outer end of the stub, and said base wing at its inner end being of generally flat section so as to conform generally to said inner wall lower edge and thus to be spaced below the proximate portion of the stub top wall sheet and said inward portion changing to concave-convex section at said intermediate portion to conform to the section of the outer end of the stub, whereby said inward portion and said stub converge laterally outwardly from said inner wall and meet at the junction of said stub outer end and said intermediate portion.

11. The invention defined in claim 10, in which: said base wing in its intermediate portion is vertically offset to afford a fore-and-aft shoulder of a depth commensurate with the thickness of the stub sheet and receiving said stub outer end so that the upper surfaces of the stub and the outward portion of the base Wing are substantially flush at the junction therebetween.

12. The invention defined in claim 10, in which: the base wing includes in its inward portion an upwardly recessed part afiording a downwardly opening strutreceiving pocket concealed from above by the overlying top wall.

References Cited in the file of this patent UNITED STATES PATENTS 2,347,689 Johnson May 2, 1944 2,560,742 Reder July 17, 1951 2,676,431 Goldberg Apr. 27, 1954 2,724,211 Bloom Nov. 22, 1955 FOREIGN PATENTS 630,222 Great Britain Oct. 7, 1949 752,992. Great Britain July 18, 1956

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