US2890489A - Tank building form - Google Patents

Description

June 16, 1959 H. NOYES ET AL 2,890,489

TANK BUILDING FORM Filed March 21, 1952 4 Sheets-Sheet 1 INVENTOR. H O WAR D NOYE S EDWARD W. MOORMAN TT'Y.

June 16, 1959 H. NOYES EIAL 2,890,489

TANK BUILDING FORM Filed March 21, 1952 4 Sheets-Sheet 2 INVENTOR. HOWARD NOYES 20 55 2i EDWARD W.MO0RMAN June 16, 1959 H Es ETAL 2,890,489

TANK BUILDING FORM- 4 Sheets-Sheet 3 Fil ed March. 21 1952 ATT'Y.

H. NOYES ET AL TANK BUILDING FORM June 16, 1959 4 Sheets-Sheet 4 Filed March 21, 1952 INVENTOR.

HOWARD NOYES Y EDWARD W. MOORMAN fiwe ATT'Y.

United States PatentO T BUILDING FORM Howard Noyes and Edward W. Moor-man, Dayton, Ohio,

assignors to The Dayton Rubber Company, a corporation of Ohio Application March 21, 1952, Serial No. 277,804

3 Claims. (Cl. 18-45) The present invention relates to building jigs for use in making fuel tanks of the type extensively used in aircraft and more particularly relates to building jigs, a portion of which is adapted for repeated use.

The flexible types of fuel tank or fuel cell, to which the present invention is directed, were made heretofore by building up the tank, layer by layer, over a rigid form having the shape it is desired to impart to the interior of the tank being constructed. The form was heretofore made of pasteboard, cardboard or other material which is easily disintegrated, so that it can be removed from the inside of the tank when the work of forming the tank has been completed.

After the tank form has been provided, it is covered with a number of layers or laminations of rubber and fabric with intermediate layers of rubber or other cement. When a sufiicient number of such layers have been applied to build up the wall of the tank to the desired thickness and structure, the various tank fittings have been incorporated and the tank vulcanized. The form is then destroyed by softening it in hot water and removing the disintegrated parts through a manhole or other opening in the tank.

The present invention contemplates an improved fuel tank building form wherein parts of the form are recoverable for repeated use thereby greatly reducing the cost of the expendable forms heretofore in use.

This is accomplished by providing the building jig in the form of a framework comprising two end members or brackets, a number of center supports, and a number of elongated reinforcing and supporting members, which are shown for purposes of illustration as four lengths of cardboard tubing, the pieces of tubing being attached to the end brackets and supported by the center supports. To this framework, cardboard panels are attached by means of glue to complete the building form. Wood molding blocks with one side having the same contour as the cardboard tubes are glued to the tubes to provide a suitable surface for attaching the cardboard side panels. The cardboard tubes, in addition to providing lateral strength, are of a size necessary to give the proper radius for the edges of the tank.

The end brackets and center supports are made of a permanent material and can be recovered for re-use, while the cardboard tubes and side panels are expended with each tank used. In order to facilitate removal from the tank after building and curing, the end brackets and center supports are made in two parts that are latched together during assembly, and can be disassembled by reaching an arm through a regular opening in the cured tank, releasing each latch, and removing each of the pieces, one at a time, through the same opening. Preformed shapes of cardboard, plastic or papier mach may be used for reinforcement and the forming of various radii at the corners. While the elongated reinforcing members have been illustrated in the form of paper tubes, elongated members of other shapes or curvature may be Patented June- 16, 1959 used, for example, instead of tubes, curved cardboard strips may be used which will be engaged by the end members in any desired manner. In place of paper or other disintegratable material, the elongated membersmay be made of re-usable material, such as cotton, plastic, metal, or the like, formed in interlocking sections so that these members can be taken apart and removed through the opening in the finished tank.

By employing the method and form of the present invention, not only is there a saving in the cost of the forms used, but there is also a saving in the cost of labor involved. Furthermore, the building jig of the present invention is of more rigid construction than forms heretofore used.

The above and other features and advantages of the present invention will be apparent from the following. detailed description taken in connection with the accompanying drawings, wherein:

Figure 1 is a perspective view of the fully assembled fuel tank building form forming the subject matter of the present invention.

Figure 2 is a similar view of the form with the cardboard panels removed.

Figure 3 is a transverse sectional view through the tank building jig showing one form of center support, taken along line 3--3 of Figure 2.

Figure 4 is a similar view of a modified form of center support.

Figure 5 is an elevational view of the center support shown in Figure 3.

Figure 6 is a similar view of the center support shown in Figure 4.

Figure 7 is an elevational view of one form of end member assembly.

Figure 8 is a side view thereof.

Figure 9 is an elevational view of a modified form of an end member assembly; and

Figure 10 is a side view thereof.

Referring to the drawings in detail, and more particularly to Figures 1 and 2, the fuel tank (not shown) is built up about a form composed generally of a pair of end members 11, 12', a plurality of center supports 13, 14, 15 and 16, and four cardboard tubes 17, 18, 19 and 20. The form is completed by attaching cardboard panels, indicated generally by numeral 21, to the frame in a manner to be described.

In one form of the invention shown specifically in Figures 1, 2, 3, 7 and 8, the center supports and endassemblies are formed of metal, preferably aluminum, while in the other modification shown specifically in Figures 4, 6, 9 and 10, the center supports and end assemblies are formed of wood, preferably waterproof or marine plywood.

As seen in Figure 3, the center support 13 comprises two complementary sections 22 and 23 each forming one half of the center support. The section 22 comprises a vertical angle strip 24 suitably joined to an upper horizontal angle strip 25 by means of a corner bracket 26. The lower portion of the section 22 combines the horizontal angle and corner bracket indicated by numeral 27. The section 23 includes similar parts 28, 29 and 30. As seen in Figure 5, the brackets 26, 27, 29 and 30 are curved at 31 to conform to the longitudinal tubes 17, 18, 19 and 20.

The sections 22 and 23 are constructed to form a rigid:

bracket members 27 and 30 are similarly provided with i a tongue 35, a groove 36 and a latch 37.

The center supports 14, 15 and 16 are similarly constructed. v

The end assembly 12, shown in Figures 7 and 8, is also formed of metal, preferably aluminum, and consists of the vertical members 38, 39 having horizontal sections 40 and 41 forming the upper edge and lower horizontal sections 42 and 43 forming the lower edge of the end assembly. The various portions making up the assembly are suitably shaped to define the curved interior edges of the tank being formed. The members thus described are hollow and sector-shaped in cross section. Angle members 44 and 45 are secured to the vertical members 38 and 39 for added strength and to provide a bearing surface for the cardboard side panels and end panels. Additional angle members 46 and 47 are secured to the horizontal sections 40, 41, 42 and 43. The horizontal sections are formed with a tongue and groove construction similar to the construction previously described in connection with the center supports and similar latches 48 and 49 are provided for securing the assembly in locked position. The latch mechanisms in the end assemblies are fastened at a 45 angle to facilitate disassembly. At each corner of the end assembly, spool members 50, 51, 52 and 53 are secured to the assembly and are of suchsize as to receive the ends of the tubes 17, 18, 19 and 20. The opposite end assembly 11 is similarly constructed.

In order to provide a suitable surface for attaching the panels 21, a plurality of Wood blocks are glued to the tubes 17, 18, 19 and 20. These blocks, indicated by numeral 54, are suitably shaped to provide the glueing surface with the same contour as the cardboard tubes. The blocks are suitably spaced along the tubes to receive the center supports in the space between adjacent blocks thus serving as a means for properly locating the supports. T

From the foregoing description, the manner of assembling the completed building form will be readily apparent. The wood molding blocks 54 are adhered to the four cardboard tubes with a water soluble adhesive and the ends of the tubes are mounted on the spools of the end assemblies 11 and 12. The center supports are positioned in the spaces between adjacent blocks and the cardboard panels are glued to the blocks with a water, soluble adhesive. To provide a smooth exterior surface for the form, paper tape, indicated by numeral 55, is secured over the various joints. After the joints have been taped, and the tank fittings secured to the panels, the rubber compound forming the tank proper is applied to the form in a well-known manner and cured. If desired, the cavity between the edge of the panels and the cardboard tubes or other elongated member, which cavity is shown as 70 in Figures 3 and 4, may be filled with a strip of rubber extruded in the shape of the cavity before application of the paper tape. This strip can then be curved when the form is dismantled and removed from the tank.

After the curing step, the assembly is soaked in Water causing disintegration of the cardboard panels and tubes. The end assemblies and center supports are disassembled by a workman reaching an arm through an opening, as at 10, Figure 1, in the cured tank and releasing each latch. The parts are then removed, one at a time through the same opening. Thus, it will be apparent that the cardboard panels and tubes are expended with each tank built and the metal parts available for reuse in another The center supports and end assemblies described above are made of metal such as aluminum. In a modified form as shown in Figures 4, 6, 9 and 10, the center supports are formed of wood, preferably of plywood. As seen in Figure 6, the center support, indicated by numeral 56, comprises a pair of complementary sections 57 and 58 pivotally joined together by hinges 59 and 60. The sections are suitably cut away at each of the outside corners to form curved portions cooperating with the tubes 17, 18, 19 and 20.

The modified end supports, shown in Figures 9 and 10, are formed of two complementary sections 61 and 62 hinged together by hinges 63 and 64. As seen in Figure 10, the outer edge of each support is rounded ofi to folm a smooth curved surface. A handle 65 is attached to an inner face of one of the sections to aid in the disassembly of the support. At each corner of the assembled support, wooden discs 66, 67, 68 and 69 are provided to receive the ends of the cardboard tubes as previously described in connection with members 50, 51, 52 and 53.

It will be understood that the modified center supports and modified end assemblies shown in Figures 4, 6, 9 and 10 are interchangeable with the center supports and end assemblies shown in the first form. The panels, tubes and wood molds previously described can be used with either form of center support or end assembly. In the assembly or disassembly of the modified construction the mode of operation is the same as previously described except that the parts are folded together to be removed through the tank opening as distinguished from the first form wherein the complementary sections are completely separable.

It will be understood that various changes in details of construction can be made without departing from the spirit of the invention, the scope of which is commensurate with the appended claims.

We claim:

1. A form for the manufacture of hollow rubber articles and the like, which comprises a pair of spaced end assemblies, a plurality of spaced elongated members of water disintegratable material which engage a corner of each end assembly, thereby forming a frame and defining the corners of the form, at least one interior member positioned intermediate the ends of said frame engaging and bracing said elongated members, said end assemblies and said interior member being of water resistant material but sectionally collapsible, and a plurality of water disintegratable wall panels secured to said frame and engaging the corners thereof whereby the curvature of the corners is defined by the curvature of the spaced elongated members.

2. A form for the manufacture of hollow rubber articles according to claim 1 wherein said wall panels are secured to the frame by means of spacing blocks mounted upon said water disintegratable elongated members and providing a planar seating surface coextensive with said reinforcing members to receive said wall panels.

3. A form for the manufacture of hollow rubber articles according to claim 2 wherein said spacing blocks are separated to provide spacing means for holding said interior members in fixed transverse position at determinate points along the length of said water disintegratable elongated members.

References Cited in the file of this patent UNITED STATES PATENTS

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