US2082792A - Sheet metal beam - Google Patents

Description

June A8., 1937.

SHEET M ETA'L BEAM Filed March 28,' 1934 P1615 z JNVENTOR.

VALBERT GDEAN.

r A. Gpl-:AN 2,082,7924

Patented June 8, 1937 UNITED s'rli'rusy PATENT .OFFICE :.osam

Albert G.

Edward sppumins man sa', m4, sem n. 11am z calm; (c1. rss- 41) the parts are well adapted to beingsecured by riveting 'or other suitable forms of attachment.

The invention has particular reference to light structural work, as light busses, light rail cars, air craft, marine super-structures and the like. 'I'he main object ofthe invention is the provision of a girder, beam or column structure y capable of giving maximum strength for the weight of material employed, with simplicity and .ease of construction, of a form capable of fabri' cation by machine spot welding especially on an automatic machine of the type known as a progressivewelder, and amenable to use as a structural element in the fabrication of structures by spot welding, and in a manner which makes possible the economical use of relatively expensive high tensile material, such as stainless steel.

An ancillary object is the provision of a beam or column having 'the above qualitiesand composed of elements capable of being formed from high tensile sheet material with substantially no spring-back and with a deiinite permanent set, that is one in which most of the deformation is -in the plastic range rather than in the elastic range, and this by a simple rolling process of the nature of what might be termed brake rolling in which the metal is simply bent, and consider-J able tolerance is permitted in accuracy of adjustment oi rollers, as distinguished from die rolling in which there is a substantial ilow of metal and the adjustment of the rollers with respect to the gauge of the metal must be made with extreme exactitude. l

The -above and other objects and advantages of the invention are attained by the novel con'- 4,0 struction arrangement and cooperative' relation of parts as will be clearly set forth in the following'specication, reference being had to 'A the drawing accompanying the-same.

In the drawing:

Fig. 1 is a perspectiveview of' one of the ele- Fig. 5 shows attachment ot lnarrow gusset.l

Fig. 6 .shows attachement of wide gusset. Referring vto the 'drawing in detail, and first to Figures 1 to 3, the beam as here shown is composed of four wall elements, a pair of spaced :opposed top and bottom wall elements i and 2, 5 '4 anda pair of spaced opposed side wall elements 3 and 4. These wail elementsA are substantially identical in shape and dimensions. Each element is of the form shown in Fig. l, which is that of a trough member having a central longi- 10 tudlnal bead 6 in the bottom wall ofthe trough projecting inwardly of the trough, to approximately the depth of the trough. It will be noted that this particular form of section is capable of being simply bent into form from strip sheet ,15 material, which bending may be accomplished through the use of any suitable or other known form of bending means such as bending rollers, and that because of the fiat surfaces and relatively abrupt or sharp angular changes in con- 20 tour it is lcapable of being bent into the shape' shown with a dente permanentset and withv substantially no spring-back, which latter is prevented by the avoidance of curved contours or l rounded corners. This shaping of the beam with 25 fiat surfaces and deilnite breaks in contour makes possible a deilnite permanent set in the deformation without the'use of close fitting dies, and with substantially no change in gauge due to the deformation, which quality renders it s ,capable of economical production` from ,strip stainless steel without detriment to the valuable characteristic qualities of this material, and makes forV economy in quantity production due to its simplicity and economical use of material, and 35 the lsimplicity of apparatus necessary for its formation.

The beam construction shown in Figures 2 and 3 consists of four elements such as swn in Fig. 1. which may be exactly alike, or may vary 40 slightly in dimensions-according to the desired cross sectional dimensions of the `ilnished beam or column. In this. form it comprises the pair of opposed wall members |2, facing inwardly -of the beam. with a pair of opposed side wall 45 members 3 1, positioned within and between the first two members and facing outwardly of the beam. The sides 6 oi the channel elements 3 and 'l are seated against the inner surfaces of the bot-v.

tom wall of the channel members 4I and Zbetween 5o the base edges of thebea'ds 5, and the side walls Bof the members i and 2. The side walls 6 of the channel members land l are preferably, substantially Ythe width of the spaces between the base of the beadand the side wallof the upper 55 and lower members I and 2. The parts` are secured together in the relation shown, to form a rigid beam structure by spot welding the flanges 8 of the side elements 3-4, to the bottom walls of the top and bottom members I and 2 where such ilanges and bottomwalls lie in flat contact with.v each other, which welding may be done by y a straight line of spot welds, as shown in Fig..2 where the spot welds are indicated by the nu- 10 mtal 1.

An advantage o! having the width of the anges 6 of the side wall members substantially ll the spaces between the beads 6 and the side wall B of the upper and lower members, is that it not only enables the parts to be properlyvheld in place for welding without the use of elaborate jigs but substantially eliminates the chance of making the welds at the edge of the side wallsv 6 of the side members in welding them to the top members. As the space-around the portions tobe welded together, that is, around the contacting surfaces of the sides 6 of the side channel members and the bottoms of the top and bottom members is clear and unobstructed in a longitudi'nal direction, the parts so assembled and related lend themselves readily to being welded by a "progressive welder or automatic straight line l spot welder.

As will be clear from Fig. 3, the sides 6 of the channel elements are of such depth that on the outside elements I and 2 they may function both as stiffenlng means and attaching anges for eecting a spot welded connection between a nished beam and gussets or other structural elements. 'I'he inished beam or column is thus provided with a set of four L-section ilanges formed by the side walls of the outside channel section elements I and 2, and a portion of their bottom walls between the side walls and the bases of the 40.beads 5. There is one such L-section attaching ange on each corner edge of the beam, the four flanges being so directed as to enable the beam to be spot welded to a at surface on any of these four sides by two parallel lines of spot 45 welds. Where gussets or other dat structural members are to be secured to the top and bottom sides of the beam as positioned in Figures 2 and 3 by spot welding, overlapping of the second groupl of spot welds with the original spot welds used in formingl the beam may be avoided either by omitting spot welds from those portions of the beam where such other structural elements are to be attached, or by the use of a beam completely Welded and taking care that in the subsequent welding thereto of other structural elementsthe second line of welds are staggered in relation to the iirst.

' Where attachment is to be made against the sides ofthe beam as shown in Figures 2 and 3, to gussets or other flat structural elements, the spot welds are made through lthe side walls 6 of` the top and bottom channel sections. Reference to Fig. 3 will kindicate how the application of one member .of the spot lwelding tool to the inner surface of the L-shaped attaching flange is permitted by the shape and arrangement of the elements constituting the beams, in which figure two electrode members of the spot welding tool 70 are -indicated in dotted lines at 8 and 9. It will also be clear from Fig. 3 how the particular form of bead 5 affords maximum strength and at the II) and II for welding gussets or the like to the horizontal portions of the L-shaped anges.

Where relative narrow gussets are to be attached, especially to the outer members of the L-section flanges, a suitable shaped welding elec- 5 trode I3 may be inserted under the flange from the side of 'the gusset-as indicated at Fig. 5, and where the gussets are of too great a width to allow for this, the gussets may be made of the double type or provided with intermediate open sections 10 to permit the insertion of the welding tool I3 as indicated in Fig. 6.-

Where the beam is to be made quite small, say of a depth of 2 inches or less, the modication of Fig. 4 is used, in which the elements are like those 15 of the beam shown in Figs. 1 to 6, in all respects except that the side elements I 4 and I 5 are formed with the central longitudinal beads I6 projecting outwardly of the channels. As indicated in dotted lines in Fig. 4, this allows ready access to the 30 inside of the L-shaped edge flanges of the smaller beam with the same set of electrodes 8 and 9 as used on the large beam.

A practical advantage of the invention embodied in the form shown in` Fig. 2, is that all four l0 elements constituting the beam are identical thus effecting economy in machinery for forming the elements.

A marked practical advantage of the peculiar .section of the present beam, as will be observed :"0 from inspection of both Figs. 3 and 4, is that the beammay be slightly compressed in th direction of either its width or its depth, or bo h without substantial spring-back, to effect slight alteration r vin its cross dimensions where expediency requires, 3" without weakening the beam, and without substantial change in the section contour. While I have thus herein shown and described certain specific embodiments of my invention for the sake 'of disclosure, it is to be understood that 40 the invention is not limited thereto, but contemplates all such modiflcations and variations thereof .as fall fairly within the scope of the appended claims.

What I claim is: 45

l. A box section beam comprising top and bottom members of inwardly facing channel section, and side members of outwardly facing channel sectionA having their side walls secured to the bottom walls of the top and bottom members, all 50 of said members having a section oi' substantially the same shape and size, each of said channel sections having a iiat sided V-shaped symmetrical beading projecting inwardly of the channel at an abrupt angle to the bottom wall and leav- '55 sile sheet metal with a definite permanent set which comprises four substantially identical wall 65 ielements each of which has at body portions and an intermediate V-shaped reinforcing channel between said at body portions and at iianged portions at substantially abrupt angles to said body portions exterior thereof, said wall elements being paired in opposed relation, the at body portions o1 one pair of opposed elements acting as chord members reinforced by the intermediate V-shaped channel .and the exterior anged portions, the second pair of opposed elemourra' 3' ments acting es webs sndrelnforoed by lntcr- "the web members. the donnes" of all elements mediate' V-shaped channels and the exterior anges, the `flanges o! the acting web elements being secured to the body vportions of the actlng chord elements, said actlns'chord elements' oonsti'tuting cover members to form n box beam wlth being exposed to hcllltte welding. auch beams 4 being relatively compressible 1n wldtlinnd depth to effect slight alteration in its cross sectional l ALBERT. c+. nm.

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