US1388543A - Rib for airplane-wings and the like - Google Patents

Description

W. H. BARUNG.

RIB FOR AIRPLANE wmes AND THE LIKE.

APPLICATION FILED JULY 3. 1920- 1,388,543.

Patented Aug. 23, 1921.

INYENTOR Wu r52 #51721 0Y6 ATTORNEY.

UNITED STATES WALTER H. BARLING,

OF LONDON, ENGLAND.

RIB FOR AIRPLANE-WIN GS AND THE LIKE.

Application filed July 3,

T 0 all whom it may concern Be it known that I, WALTER H. BARLING, a subject of the King of Great Britain, residing at London, in the county of London, England, have invented certain new and useful Improvements in Ribs for Airplane Wings and the Like, of which the following is a specification, reference being had therein to the accompanying drawing.

This invention relates to a rib for Wings and the like.

The object of the invention is to provide a rib of this kind which will be of a very light weight and will be very strong and durable; and to this end it is a further object of the invention to provide a rib of this kind of trussed formation, in which the truss bars and joints will have the requisite strength.

WVing ribs, as commonly constructed, comprise top and bottom caps in the form of flat strips of wood and usually these caps are airplane connected one to the other by a thin web of wood connected at its edges with the respective caps between their lateral edges. In a trussed formation inwardly extending flanges are attached to each of the caps in lieu of the vertical web and the truss bars must be connected to these flanges, which are of thin, light material. In a trussed rib the alternate truss bars constitute respectively tension members and compression members. The tension members may be of thin light wood and can be attached to the flanges of the caps without great difficulty, but the compression membersmust be of such size and strength as to receive the several compression strains to which they are subjected, and because of the difliculty in attaching the ends of these compression members to the flanges of the caps, no satisfactory trussed rib has been produced.

It is, therefore, a further object of the invention to provide, in a wing rib of this kind, a truss bar of such character that it can be readily attached to the flanged rib and to provide efiicient means for so attaching the same.

t is also a further object of the invention to provide means for relieving the caps of the shearing strain imposed thereon by the spars.

Other objects of the invention will appear as the device is described in detail.

In the accompanying drawings Figure 1 is a side elevation of a rib embodying my in vention, showing the spars in cross section;

Specification of Letters Patent.

secured to the cap Patented Aug. 23, 1921. 1920. Serial No. 393,900.

Fig. 2 is a plan View of the rib; Fig. 3 is an enlarged detail of one of the joints; Fig. 4: is a transverse sectional view taken on the line 4-4 of Fig. l with the diagonal member broken away; Fig. 5 is a cross section of a compression bar; Fig. 6 is a detail view of a portion of the rib showing the reinforcing means to protect the caps against the shearlng action of the spar; Fig. 7 is a modified form of the device shown in Fig. 4; and Fig. 8 IS a perspective detail view of one of the chocks.

In these drawings I have illustrated one embodiment of my invention and have shown the same as comprising upper and lower longitudinal frame members, each of which comprises a cap 1 of thin wood and an inwardly extending longitudinal flange 2 midway between its lateral edges, thus giving the longitudinal members a T-shape in cross section. If desired the caps may be tapered from the spars to the front and rear edges, respectively, of the wing, as there is little strain 011 the rib near the edges of the wing, and by so tapering the caps a saving in weight is effected which in the case of large ribs is appreciable. The two longitudinal members are connected together and braced one against the other by truss bars 3 and 4: extending diagonally thereof and connected at their, ends with the respective longitudinal members. The truss bars 3 are tension bars and may be of thin light wood, while the bars 4 are compression bars and must be of such a construction that the will be able to resist the bending or buc ling strains to which they are subjected. When made of a size suflicient to impart thereto the necessary strength, the compression bars are so much thicker than the vertical flanges of the longitudinal members that they cannot be readily attached thereto in a practical manner. In order that the compression bars may be readily attached to I have reduced the end portions,

the flanges of the bars to a thickness substantially equal to the thickness of the flanges. This leaves the intermediate portion of the bars, which is subjected to the most severe strain, of the desired thickness, but enables the ends of the bars to be placed in engagement with the edges of the plates 5, which are arranged on opposite sides of the flanges and overlap both the flanges and the reduced end portions of the compression bar, and are preferably of multiply wood. In the arrangement here shown the adjacent ends of the corresponding tension bars and compression bars are brought together in the form of a V and the ends of both bars are shaped to provide a flat contact surface between the same and the inner edge of the flange. in plates are in the form of short strips of thin wood of a width sufiiciently greater than the flanges to enable them to overlap the end portions of the two truss bars; The plates are secured to the flanges and to the truss bars both by glue and by screws, or bolts, and the construction is such as to pro vide large gluing areas for the plates on both the flanges and the ends of the truss bars, this large area being also available for the insertion of the screws or bolts, thus enabling a sufiicient number of screws to be used without placing them so close together as to weaken the construction. The compression bar may be of any suitable cross sectional construction, but I prefer to employ a truss bar which is cruciform in cross section, as this provides a large degree of strength in proportion to its weight, and by terminating the lateral flanges of the cruciform bar at a point spaced away from the ends of the bar, the ends are given a thin flat shape which readily adapts them for connection withthe flanges of the longitudinal members of the rib. The ends of the lateral flanges ofthe compression bar bear against the edges of the attaching plates and serve thus to further'reinforce the joint. The rib is also provided with vertical bars extending between I the two longitudinalmembers at pointswhere the diagonal truss bars are connected therewith. As here shown, these vertical members are in the form of thin flat strips 6, each of which has one end extending between the adjacent ends of two truss bars, the corners of the truss bars being cut away to provide a flat contact surface between the same and the vertical bar. are secured in place by the overlapping plates 5 which secure the truss bars to the flanges of the longitudinal members. At

their 'oppositeendsthe vertical bars 6 engage the edges of the flanges and are connected thereto by attaching plates 7 which overlap the flan es and the ends of the bars and may be. attac ed thereto by glue and screws.

This construction results in a rib of very the compression bars being of the size necessary to give themthe required-strength and'being attached to the longitudinal memhers by a ve easily manufactured at a relatively low cost.

The rib is provided near its front andrear ends with transverse passageways, or sockets, to receive the spa-rs 8, the fian 5 2 being cut awayso that-the spars. willdi rectly engage The connect- In this manner the vertical bars strong rigid joint." Further, the construction is such that the rib can be two vertical bars 9, the ends of which contact with the inner ends of the respective flanges 2 and are attached to the flanges by means of attaching plates 10. The end of the adjacent truss bar is arranged in the angle between the flange and the vertical bar 9 and the attaching plates 10 overlap the end of this bar and serve to secure it also to the flange of the longitudinal member. The two vertical bars are spaced apart to receive be tween them the spar and in order to relieve the caps of the upper and lower longitudinal members of the shearing strain which would otherwise be imposed thereon by the spar, I have provided the parts which form the passage way with inwardly extending portions, or projections which engage the spar and receive the strains imposed thereon. In the present construction the spar is formed of upper and lower booms which are spaced some distance apart and the projections from the walls of the passage way extend between these parts and engage the inner surfaces of the respective booms, or longitudinal members, of the spar. These projections may be carried either by the attaching plates 10 or by the vertical members 9. In Fig. 6, I have shown the plates 10 as having projections, or lugs, 11, extendin beyond the vertical members to engage t e inner surfaces of the respective members of the spar, while in Fig. 7 I have shown the vertical members 9 as having inwardly extending lugs which engage the inner surfaces of the respective members of the spar. Either construction is erlicient, but that shown in Fig. 6 is the most satisfactory, both in manufacturing and service. I also prefer to reinforce, or brace, the joint at the spar by inserting in the angles between the attaching plates 10 and the longitudinal members of the spar, short blocks, or checks, 12 which are angular in cross section and are here shown as short p u I preferably by rubbing. light weight and of relatively great strength,

It will be apparent from the foregoing description that I have produced a wing rib which is of a very light weight and of a very strong, durable character, and that these characteristics of the rib result largely from the constructionwhic-h enables truss bars to be employed and to be rigidly secured to the longitudinal members of the rib, and further, that the strength and durability of the rib is increased by the reinforced construction at the passage ways for the spare While. I have shown and described one embodiment of the invention I wish it to be understood that I do not desire to be limited to the details thereof as various modifications may occur to a person skilled in the art.

Having now fully described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In a rib of the character described, up per and lower members having inwardly extending longitudinal flanges, diagonal bars extending between said upper and lower members, one of said bars having a relatively large intermediate portion and having its ends reduced in thickness adjacent to said flanges and arran ed in line with said flanges, and means For attaching the ends of said bars to the respective flanges.

2. In a rib of the character described, up per and lower members having inwardly extending longitudinal flanges, diagonal bars extending between said upper and lower members, one of said bars having a relatively large intermediate portion and having its ends reduced to substantially the thickness of said flanges and engaging the inner edges oi said flanges, and attaching plates overlapping and secured to said flanges and the reduced portions of said bars.

3. In a rib of the character described, upper and lower members having inwardly extending longitudinal flanges, diagonal bars extending between said upper and lower members, one of said bars comprising a member of substantially the thickness of said flanges, arranged in line with said flanges, and having laterally extending flanges formed integral therewith and terminating at points spaced from the ends of said memher, and attaching plates on both sides of said bar at each end thereof and overlapping the adjacent longitudinal flanges.

4:. In a rib of the character described, upper and lower members having inwardly ex, tending longitudinal flanges, two series of diagonal bars extending between said upper and lower members and having their respective ends arranged adjacent one to the other, the bars of one series having relatively large intermediate portions and having their end portions reduced to substantially the thickness of the flanges of said upper and lower members and arranged in line therewith, and attaching plates secured to both sides of the respective flanges and overlapping the ends of the respective diagonal bars.

5. In a rib of the character described, upper and lower members having inwardly extending longitudinal flanges, two series of diagonal bars extending between said upper and lower members and having their respective ends arranged adjacent one to the other, the bars of one series having relatively large intermediate portions and having their end portions reduced to substantially the thickness of the flanges of said upper and lower members and arranged in line therewith vertical bars extending between the flanges of said upper and lower members and each having one end arranged between the adjacent ends of two of said diagonal bars, and attaching plates secured to both sides of the flanges of the upper and lower members and overlapping the respective ends of said diagonal bars and said vertical bars.

6. In a rib of the character described, a truss bar cruciform in cross section and having its lateral flanges cut away near the ends thereof to provide said bar with flat end portions.

7. I11 a rib of the character described, upper and lower members having inwardly extending longitudinal flanges, diagonal bars extending between said upper and lower members, vertical bars extending between said upper and lower members, attaching plates for securing said vertical bars to the flanges of said upper and lower members, said vertical bars being spaced apart, and said vertical bars and said attaching plates forming the side walls of a passageway for a spar, said walls having inwardly extending projections to engage a portion of said spar and receive strains imposed by said spar on said rib.

8. In a rib of the character described, upper and lower members having inwardly extending longitudinal flanges, diagonal bars extending between said upper and lower members, vertical bars extending between said upper and lower members, and spaced apart to form a passageway tor a spar, attaching plates overlapping the flanges of said upper and lower members and the respective ends of said vertical bars and having portions extending beyond the respective bars into said passage way and arranged to engage the inner edges of the respective parts of said spar.

9. In a rib of the character described, upper and lower members having inwardly extending longitudinal flanges, diagonal bars extending between said upper and lower members, vertical bars extending between said upper and lower members, attaching plates for securing said vertical bars to the flanges of said upper and lower members, said vertical bars being spaced apart, and said bars and said attaching plates forming the side walls of a passagevmy for a spar, said walls having inwardly cxtending projections to engage a portion of said spar and receive strains imposed by said spar on said rib, and angular blocks fitted in the angles between the respective attaching plates and the sides of said spar and rigidly secured to said plates and said spar.

10. In a rib of the character described, upper and lower members, each comprising a cap, said rib having near one end thereof a passageway to receive a spar, the caps of sald upper and lower members having their end portions tapered, said tapered portions beginning at points adjacent to said passageway and extending substantially to the end of said rib, and a connecting member extending between said upper and lower members. 7

'11. In a rib of the character described, upper andlower members each comprising a cap, said rib having passageways near the ends thereof to receive spars, said caps having their end portions tapered, said tapered portions beginning at polnts adjacent to the respective passageways and extending substantially to the respective ends of said rib, and a connecting member extending between said upper and lower members.

In testimony whereof, I afiix my signature hereto.

\VALTER H. BABLING.

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