Aug. 13, B. N, WALLIS ET AL 1,724,440

Transcription

1 Aug. 13, B. N, WALLIS ET AL RIGID AIRSHIP Filed Aug. 19, Sheets-Sheet l

2 Aug. 13, B. N. WAllis ET AL RIGILD AIRSHIP Filed Aug. 19, Sheets-Sheet 2 g) & ses & s & & 3. & a77oa/ways

3 ) O Patented Aug. 13, (fr. 1 * ES Sea ATENT OFFICE. BARNES NEVILLE WALLES AND CHARLES DENNISTON BURNEY, OF WESTIMINSTER, ENGLAND, ASSIGNORS TO A.ERS:IE (3 JARATTTE: COFEPANY., LIMITED, OF WEST IVIINSTER, ENGLAND, A BRITISH COMPANY. - RGO ARSt. Application filed August 19, 1927, Serial No. 214,033, and in Great Britain September 17, This invention relates to rigid airships of both the longitudinal girders and the inter 55 the kind which comprise longitudinal gird Secting transverse frame members are tri ers extending from the bow to the stern of angular in cross section, the apex of the the ship and transverse frames which inter longitudinal girder pointing outwards and. sect the longitudinal girders at intervals and the apex of the transverse frame pointing which frames are usually of the form of inwards or vice versa, and, at their points of 60 polygonal rings. intersection, the longitudinal girders are In the past it has not been possible to built into and secured to the transverse revolve or determine in an accurate manner frames with their centroids coincident with the various forces acting at different points those of the transverse frame, the point of throughout the framework of an airship and intersection forming the centre of a struc 65 the latter has accordingly been more or less ture the extremities of which lie on the sur of a redundant structure comprising a large face of an imaginary sphere or spheres. number of relatively small members which In previous systems, it has been common have been interconnected in such a manner to make connections from the mesh wiring that the forces set up are distributed inde which supports and encloses the gas con 70 terminately throughout the component parts tainers direct to the longitudinal members, of the structure. As the exact nature of the from whence the lifting forces were in turn forces acting on any particular member or transferred to the transverse frame mem group of members in a highly redundant bers. Owing to the fact that the load is structure can only be estimated with an ap transferred to the longitudinal members as a 5 proximate degree of exactitude, it has been beam it is difficult in this system to estimate impossible to reduce their weight to the the stresses set up in the framework. inimum while preserving any required fac In order to secure a more direct applica tor of safety. tion of the lifting forces to the framework The object of the present invention is to of the airship it is proposed to attach the reduce to the minimum the number of com mesh wiring to the framework at the points 80 ponent parts in the structural framework of intersection of the longitudinal girders of an airship and, by an equal or propor and the transverse frames..... tional distribution of the load throughout In cases, for example, where the longi the members of a framework specially de tidinal girders are of triangular cross sec 85 signed to support it, to secure a reduction tion, each corner of the triangle being con in weight and produce a simplified structure stituted by a tube, a member (hereinafter in which any necessary factors of safety termed a longitudinal spider) may be pro which it is desired to obtain in each com vided having three radial arms, each arm ponent part can be predetermined with ex being provided at its outer extremity with actitude. Semi-circular socket which accommodates 90 In order to obtain this result it is neces a tubular socket piece projecting laterally sary in the first instance to ensure an equal On each side of the spider. Each end of the distribution of the forces throughout con Socket piece is provided with a screw thread stituent parts of the longitudinal girders on which an internally screw threaded col 95 and the transverse frame members so that lar is mounted. The end tubular members no undue stresses or bending moments arise of each section of the longitudinal girder and to this end and according to the present are also provided with screw threads and, by invention the centroid of each transverse bringing them in alignment with the socket frame member as also that of the intersect pieces on the spider the ends of a pair of 100 ing longitudinal girders are made coincident, contiguous girder sections can be detach or approximately coincident at a point. The ably secured to the sockets on the spider lift wires and shear wires alone, together in by means of the aforesaid internally screw certain cases with the transverse bracing threaded collars. The base of each tri wires or bulkhead wiring, are connected to, angular transverse frame member, where at or approximately to, the point of coincidence each corner of the polygon the frame is in of the centroids of the intersecting frames tersected by the longitudinal girder, is se and girders. According to one arrangement cured to the longitudinal spider by a corre 05

4 2 sponding structure (hereinafter termed a spider C by means of the aforesaid inter transverse spider) so that its centroid is co nally screw threaded collars C. The trans incident with the centroid of the longitudi verse spider is of triangulated configura nal girder. To restrain angular displace tion with the apex pointing inwards to ment of the transverse spider relatively to Wards the axis of the ship and comprises the longitudinal spider the transverse three members E, E, E, the ends of which spider may be connected to the longitudinal are located within three sockets E, E, E, spider at two points. each socket E carrying a tubular socket In order that the said invention may be piece E projecting laterally on each side clearly understood and readily carried into of the spider E. Each end of each socket effect, the same will now be described more piece E is provided with a screw thread on fully with reference to the accompanying which an internally screw threaded collar drawings, in which:- E is mounted. The ends of the tubular Figure 1 is a section through one of the members B, B, of each section of the trans transverse frame members of an airship at verse frame members are provided with the point where the said frame intersects Screw threads and, by bringing them into a longitudinal girder, the transverse frame alignment with the socket pieces E, E, on members being of triangular cross-section the Spider E, the ends of a pair of contigu with the apex pointing inwards towards the ous transverse members can be detachably centre of the ship, and the longitudinal secured to the socket pieces E, E by means girders being of triangular cross-section of the screw threaded collars E, E8. As with the apex pointing outwards. indicated, one of the members E is cut in Figure 2 is a sectional end view of Fig order to permit one of the arms C to pass lure through it, the portions of the member E Figure 3 shows a suitable form of cou being connected by side plates E. The lon pling device for attaching the shear and lift gitudinal spider C and the transverse spider wires to the centroid of the longitudinal E are secured to one another so that their spider, and centroids coincide at the point P. To re Figure 4 is a section on the line 4-4 of strain angular displacement of the trans Figure 3. o verse spider E relatively to the longitudinal Fig. 5 is a perspective view of the com spider C the former is secured to the latter bined longitudinal and transverse spiders, at two points F and F. In order to provide and a degree of angular flexibility between the Fig. 6 is a view of a portion of a trans longitudinal girders A, A and the frame verse frame with the adjacent circumfer members B, B, the connections between the ential wiring to illustrate the position and longitudinal and transverse spiders may be function of the lift and shear wires, the made sufficiently flexible by Such means as longitudinal members and bulkhead wiring the use of loosely fitting bolts. The provi being Omitted for the sake of clearness. sion of this slight degree of flexibility en The longitudinal girders and the trans Sures that the deflections of the hull frame verse frame members are of triangular Work as a whole do not impose large rack cross-section as aforesaid, each corner of ing actions upon the joints of the airship. the triangle being constituted by a tube, and As the intersecting longitudinal and trans the tubes being interconnected by means of verse spiders C and E can, as aforesaid, bracing members (not shown). A, A, are be bounded by an imaginary sphere any the tubes forming part of the longitudinal Variation in the angular relationship be girder... and B, B are the tubular corner tween the two spiders will not vary the members of the transverse frame. The lon point of coincidence of their centroids pro gitudinal spider has three radial arms vided the same vertical relationship of the C, C, C, attached at their inner ends to a intersecting parts is not altered. The point triangular connecting piece C", each arm of intersection of the centroids is arranged being provided at its outer extremity with so that it occurs at the axis of the longi a semi-circular socket C which accommo tudinal spider and at this point, an axial dates a tubular socket piece C projecting opening C is provided through which end laterally on each side of the spider. Each pieces G, G for the lift wires, and end end of each socket piece C9 is provided with pieces H., H for the shear wires are passed, a screw thread on which an internally screw the said end pieces being secured in posi threaded collar C is mounted. The ends tion by a coupling device. A suitable form of the tubular members A, A, of each sec of coupling device is illustrated at Figures tion of the longitudinal girder are also pro 3 and 4 and comprises a sleeve I to be fitted vided with screw threads, and, by bringing within the apertures C and through which them into alignment with the socket pieces the end pieces G, G and H., H for the lift C, C' On the spider C the ends of a pair and shear wires G and H' are threaded, the Of contiguous girder sections can be detach wires being secured in place within the sleeve ably secured to the socket pieces C on the for example by means of Swaging or of soft 5 O O 5

5 O ) metal J which is poured around the wires and allowed to set. Alternatively soft metal may be compressed around the wires or the wires may be secured in position by means of a bolt carrying suitable fork ends for the reception of similar ends attached to the main cables. At each of their ends the said end pieces G, G and H., H carry turn buckles to which the lift wires G' and the shear wires H are attached. The aforesaid arrangement may be used in conjunction with the system of mesh wiring described in Patent No. 1,658,821 and/or the system of bulkhead wiring described in co-pending patent application Serial No. 214,036, filed August 18, 1927 where a strop connects the bulkhead wiring to the point of attachment of the circumferential mesh wiring, and/or with the system of bulkhead wiring described in co-pending application Serial No. 214,328 filed August 28, 1927, where the said wiring comprises taut and slack wires together with an axial restraint. In the embodiment illustrated L. L (Figures 1 and 2) are the slack catenary wires and M is one of the taut radial wires of the said bulkhead wiring described in application Serial No filed August, 1927, and N, N (Figures 1 and 6) are the strops for connecting the bulkhead wiring to the circumferential mesh wiring as described in application Serial No. 214,036 filed August 18, As will be seen from Fig. 6, the lift wires G, the function of which is to transfer the buoyancy of the gas bags contained within the circumferential wiring to the rigid mem bers of the structure, are attached to the points where the strops N join the circum ferential wiring and pass immediately of their length, by junction with the end pieces G. Figures 1 to 4, through the centroids P of the transverse members. Similarly the shear wires H', by means of end pieces H, pass from the centroids in One transverse frame to those in the next, being crossed as indicated in Fig. 6 in order to brace the panels formed by the longitudinal and trans verse frames. In cases where the apex of each longi tudinal girder points outwards as in the ex-. ample illustrated the method of securing the outer cover in place, involving the use of tension wiring as described in English Pat ent No. 282,518, can also advantageously be employed either alone or in combination with the arrangement described in English Patent No. 280,670 where each panel of the outer cover is detachably secured to the in tersecting points of the longitudinal girders and transverse frames by means of cate naries. What we claim and desire to secure by Letters Patent of the United States is:- 1. A rigid airship in which the centroids 3 of the transverse frame members and of the respectively y intersecting S longitudinal 8. gird s ers are made substantially coincident at a point, and lift, wires and shear wires are connected to the intersecting transverse frame members and longitudinal girders substantially at the said points of coinci dence A rigid airship in which the longi tudinal girders and the transverse frame members are of triangular cross section, the apex of the longitudinal girders and the apex of the transverse frame members point ing in opposite directions and wherein, at their intersection, the longitudinal girders are built into and secured to the transverse frames with their centroids coincident ap proximately at a point with those of the transverse frame members, and lift wires and shear wires are connected to the inter Secting transverse frame members and longi tudinal girders substantially at the said points of coincidence. 3. A rigid airship as claimed in claim 1, wherein intersecting longitudinal and trans verse Spiders having substantially coincident centroids are provided to which the longi tudinal girders and the transverse frame members are attached. 4. A combined longitudinal and trans yerse Spider for connecting the correspond ing members in a rigid airship, wherein the longitudinal Spider structure has three ra dial arms, each arm being provided at its Outer extremity with a tubular socket piece OO projecting laterally on each side of the spider to which the ends of the tubular por tions of the longitudinal girders are at tached. 5. A combined longitudinal and trans yerse spider for connecting the correspond ing members in a rigid airship wherein the transverse spider structure is constituted by a triangulated structure which is attached, preferably in a flexible manner, to the lon 110 gitudinal spider, the tubular end members of the transverse frame members being connect ed to Socket pieces carried by the said trans verse spider. 6. A combined longitudinal and trans 5 verse spider for connecting the correspond ing members in a rigid airship, wherein the longitudinal Spiderstructure has three ra dial arms and the transverse spider struc ture is constituted by a triangular frame the plane of which is at right-angles to that of the arms. 7. A combined longitudinal and trans verse spider for connecting the correspond ing members in a rigid airship as in claim 6, in which one of the radial arms projects 1 through one of the sides of the triangular frame A combined longitudinal and trans verse spider for connecting the correspond

6 4. ing members in a rigid airship as in claim 6, in which the centroids of the longitudinal and transverse spider structures are coin cident. 9. A rigid airship as claimed in claim 1, provided with longitudinal and transverse spiders and in which the bulkhead wiring is attached to the apex of the transverse spider. 10. A rigid airship as claimed in claim 1, 10 provided with longitudinal and transverse spiders and in which strops are provided at the apex of the transverse spider for con necting the bulkhead wiring to the circum-. ferential mesh wiring. - BARNES NEWILLE WALLIS. CHARLES DENNISTON BURNEY.