|Publication number||US3813179 A|
|Publication date||28 May 1974|
|Filing date||20 Apr 1972|
|Priority date||1 Jun 1970|
|Publication number||US 3813179 A, US 3813179A, US-A-3813179, US3813179 A, US3813179A|
|Original Assignee||Alum Elec Structures Inc|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (12), Non-Patent Citations (1), Referenced by (20), Classifications (21)|
|External Links: USPTO, USPTO Assignment, Espacenet|
United States Patent [1 1 Priest 1451 May28, 1974 STRUCTURES FORMED FROM STRUCTURAL MEMBERS Charles E. Priest, Angola, Ind.
 Assignee: Alum-Elee Structures, Inc., Angola,
 Filed: Apr. 20, 1972  Appl. No.: 246,066
Related US. Application Data  Continuation of Ser. No. 42,436, June I, 1970, abandoned, which is a continuation of Ser. No. 751,254, Aug. 8, 1968, abandoned  Inventor:
 US. Cl. 403/348, 52/758 F, 151/4173,
151/4176, 403/353  Int. Cl. F161) 39/00  Field of Search; 287718936 R, 189.36 F;
 References Cited UNITED STATES PATENTS 1,155,243 9/1915 Jordahl 52/710 1,933,536 10/1933 Awbrey 52/710 2,380,379 7/1945 Jordah1.- 52/710 2,589,304 3/1952 Spangler.... 52/729 x 2,676,680 4/1954 Kindorf 52/710 12/1954 Attwood 151/4175 2,784,812 3/1957 Kindorf 52/710 2,928,512 3/1960 Slater et al. 287/189.36 F 3,095,672 7/1963 Di Tullro et al 52/710 3,174,590 3/1965 Hoker 287/189.36 F 3,483,910 12/1969 La Lonze et al 151/4175 FOREIGN PATENTS OR APPLICATIONS 399,581 10/1933 Great Britain 52/709 OTHER PUBLICATIONS Unistrut General Engineering Calalog No. 5 pages 1 a/4 and 1 a/11 Copyright 1958 Primary Examiner-Dave W. Arola 5 7 ABSTRACT An extruded structural member having co-planar flanges with the distal edges of said flanges being in spaced relation and each such edge having an integral re-entrant flange, the re-entrant flanges being in spaced confronting parallel relation and defining therebetween a longitudinally extending slot. A T-bolt has a head having a groove V-shaped in transverse cross-section and double V-shaped in plan. The head is adapted to pass inwardly through the slot and to be rotated to engage the groove with the edges of the reentrant flanges, the flanges being deformed by said groove when theT-bolt is tightened.
4 Claims, 30 Drawing Figures PMENTEBMAY 281914 AX P. KRAUS ATTORNEY PM'E FEDNAY 28 1974 snmaora l STRUCTURES FORMED FROM STRUCTURAL MEMBERS This application is a continuation of my application Ser. No. 42,436, filed June 1, 1970, and now abandoned, which is a continuation of Ser. No. 751,254, filed Aug 8, 1969, and now abandoned.
This invention relates to structures, generally, and more particularly, to structures formed from structural members having a high degree of versatility and utility.
In accordance with my invention, I provide three novel basic types of extruded structural hollow metal members which with the use of novel T-bolt fastening elements may be assembled into a great variety of rigid open structures, such as electrical power sub-station structures, permanent scaffolding, and the like.
The extruded members preferably are formed of aluminum or any suitable light-weight metal and may be readily cut to any desired length, either on a job site or at a central point of fabrication. The character of the extruded members permit assembly of the same with other types of conventional structural members, such as flat bars, fish plates, and the like, requiring only the drilling or punching of apertures in the latter, thereby obviating the necessity of providing registering apertures in all of the structural members to receive the fastening elements. The heads of the novel fastening elements are adapted to be received in longitudinally extending slots in the extruded members and anchored in said members. The fastening elements may be moved longitudinally in said slots for positioning to cooperate with other conventional structural members which are to be secured to the extruded members.
Other objects will become apparent as this description progresses.
FIG. 1 is a perspective view of one embodiment of a representative structural assembly illustrating how my invention may be used.
FIGS. 2, 3 and 4 are fragmentary perspective views of sections of the basic extruded structural members, in accordance with my invention. I
FIG. 5 is a perspective view of aT-bolt fastening element, in accordance with my invention.
FIGS. 6 and'7 are respectively side and end elevational views of the fastening element illustrated in FIG. 5
a fastening element in assembled relation with extruded structural members. i 1
FIG. 9 is a cross-sectional view taken substantially on I line 9-9 of FIG. 8.
FIG. 10 is a view similar to FIG. 8, but showing the fastening element rotated 90 and in the process of assembly with a structural member.
FIG. 11 is a cross-sectional view taken substantially on line 11-11 of FIG. 10.
FIG. '12 is a fragmentary view of FIG. 9, but on an enlarged scale.
FIG. 13 is a cross-sectional view taken substantially on line 13-13 ofFIG. 12.
FIG. 14 is a cross-sectional view taken substantially on line 14-14 of FIG. 12.
FIG. 15 is a cross-sectional view taken substantially on line 15-15 of FIG. 13.
FIG. 16 is a fragmentary perspective view of details of an extruded structural member, showing the condi- FIG. 8 is a fragmentary cross-sectional view showing tion of the edges after engagement with the novel fastening head of my invention.
FIG. 17 is a top plan view taken substantially on line 17-17 of FIG. 1.
FIG. 18 is a fragmentary elevational view taken substantially on line 18-18 of FIG. 17.
FIG. 19 is an end elevational view taken substantially on line 19-19 of FIG. 1.
FIG. 20 is an elevational view taken substantially on line 20-20 of FIG. 1.
FIG. 21 is a fragmentary plan view of FIG. 17 on an enlarged scale.
FIG. 22 is a cross-sectional view taken substantially on line 22-22 of FIG. 21.
FIG. 23 is a cross-sectional view taken substantially on line 23-23 of FIG. 21.
FIG. 24 is a fragmentary end elevational view taken substantially on line 24-24 of FIG. 1.
FIG. 25 is a cross-sectional view taken substantially on line 25-25 of FIG. 24.
FIG. 26 is a cross-sectional view, on an enlarged scale, taken substantially on line 26-26 of FIG. 24.
FIG. 27 is a cross-sectional view, on an enlarged scale, taken substantially on line 27-27 of FIG. 24.
FIG. 28 is a cross-sectional view, on an enlarged scale, taken substantially on line 28-28 of FIG. 17.
FIG. 29 is a cross-sectional view, on an enlarged scale, taken substantially on line 29-29 of FIG. 17.
FIG. 30 is a cross-sectional view, on an enlarged scale, taken substantially on line 30-30 of FIG. 17.
Referring to the drawings, the structure illustrated in FIG. 1 exemplifies a rigid open type bay structure embodying all of the component structural members, in accordance with my invention, and illustrates how the same may be assembled with conventional structural members to produce a completed structure.
The member, indicated by the letter A, (FIG. 2) comprises a metal extrusion, preferably aluminum, having two parallel walls 35 and 36 connected by a central web 37. The walls 35 and 36 are provided with in tegral flanges 38 and 39, respectively. Said flanges are directed toward each other and terminate in re-entrant flanges 41 and 43, respectively. The flanges 41 and 43 are disposed in spaced parallel relationship and each has its free edge V-shaped in cross-section. The spaces or slots 44 and 45 between confronting flanges 38 and 39 are disposed substantially medially between the walls 35 and 36 and the spaces 44, 45 on opposite sides of the wall are in registration.
The member, indicated by the letter B, (FIG. 3) similarly is formed as a metal extrusion and comprises a cross-shaped core formed of intersecting webs 46 and 47, and a wall 48 integral with web 46 and parallel to web 47. Wall 48 includes integral flanges 49 and 51, each having a re-entrant flange 52 with the edge of each such flange V-shaped in cross-section. A pair of side walls 53 and 54 are integral with web 47 and are disposed perpendicular to wall 48 and co-planar with flanges 49 and 51. The walls 53 and 54 extend beyond one side of the web 47 a distance substantially equal to the width of flanges 49, 51, and each wall edge is provided with a re-entrant flange 56 having a V-shaped edge in cross-section. The spaces or slots 57 and 58 between the flanges 52 and 56 are disposed substantially medially between the webs 47 and wall 48 and are in registration. The walls 53 and 54 are provided with flanges 59 and 61 and each said flange is provided with a re-entrant flange 62, each terminating in an edge V- shaped in cross-section. Integral with the web 46 is a wall portion 63 which is co-planar with the flanges 59 and 61. The wall portion 63 extends on opposite sides of the web 46 and is provided along both edges with reentrant flanges 64. The spaces or slots 60 and 65 between the flanges 62 and 64 are spaced medially between the walls 53 and 54 and the web 46.
It will be seen that the structural member B affords four areas or surfaces for attachment of cooperating structural members, as will be hereinafter described.
Referring to FIG. 4, the structural member indicated by the letter C is similarly formed of extruded metal and includes a central web 66 and transverse walls 67, 68, 69 and 71, all uniformly spaced. Wall 67 is provided with integral flanges 72 and 73, each provided with a re-entrant flange 74 having a V-shaped edge. Walls 76 and 77 are perpendicular to wall 68 and coplanar with the flanges 72 and 73, respectively. Walls 76 and 77 extend on opposite sides of the wall 68 a distance substantially equal to the width of flanges 72 and 73 and each of the walls 76 and 77 is provided along its edge with a re-entrant flange 79 and 81, respectively. The spaces or slots 75 and 80 between the flanges 74 and 79 are in registration. The walls 82 and 83 are perpendicular to wall 69 and are co-planar with the walls 76 and 77, respectively. The walls 82 and 83 extend beyond one side of the wall 69 and are provided with re-entrant flanges 84. The spaces or slots 85 and 90 between the flanges 81 and 84 are in registration. Along the opposite edges of the walls 82 and 83 are flanges 86 and 87, respectively, provided with reentrant flanges 88. The wall 7] extends on opposite sides of the web 66 and is provided with re-entrant flanges 89. The spaces or slots 85 and 90 are in registration. The spaces or slots 91 and 92 between the flanges 88 and 89 are disposed substantially medially between the walls 82 and 83 and web 66.
The structural member indicated by the letter C affords six areas of attachment of other structural members, as will be hereinafter described. All of the spaces between re-entrant flanges are substantially of identical width so as to accommodate the head of a novel T-bolt fastening element, presently to be described.
Referring particularly to FIGS. 5, 6 and 7, the T-bolt fastening element of my invention, indicated generally by the numeral 95, includes a head portion 96, which is in the form of a parallelogram, and an integral threaded shank 97 provided with an undercut portion 98. The head 96 is elongated and is of such a width as to pass freely through the spaces or slots between the re-entrant flanges of each of the structural members A, B and C. The head 96 includes on its inner surface two spaced novel shaped grooves 99 and extending transversely of the head, one on each side of the shank 97. Each groove is V-shaped in cross-section, as shown in FIG. 13, and comprises two connecting V-shaped portions in allochiral relation, or a double V, as shown in FIG. 7. The bottom of one of the grooves 99 or 101 is indicated by the numeral 102 (FIG. 9) and corresponding wall portions of the two V-shaped sections are disposed in parallel planes. For example, wall portions I03 and 104 of one leg of the V-groove are parallel, and wall portions 106 and 107 are similarly parallel (FIG. 12). On the other leg of the V-groove wall portions 108 and 109 are parallel and the same is true with respect to wall portions 111 and 112.
Referring to FIG. 7, it will be seen that the grooves 99 and 101 on opposite sides of the shank 98 are disposed in allochiral relation.
The fastening T-bolt element 95 is intended to be used in connection with the aforedescribed structural members A, B and C and other conventional structural members, hereinafter to be described. In assembly, the head 96 is passed through one of the spaces or slots between a pair of re-entrant flanges in one of the structural members, with the major axis of the head 96 alined with the longitudinally extending space or slot between two re-entrant flanges (FIG. 10). The element 95 is then rotated approximately so that the opposed V-shaped edges of the re-entrant flanges are in registration with the V-grooves, as illustrated in FIGS. 8, 9 and 12-14. It will be noted that in assembled relation on the head 96 with the V-shaped edges of the reentrant flanges, such edges will engage only the ridge portions in the V-grooves, such ridge portions being identified by the numerals 113-117 and, as will be seen by reference to FIG. 12, five of such ridge portions are engaged in each V-groove.
Referring to FIGS. 13 and 14, it will be seen that the legs of each groove 99 and 101 form a right angle and the same is true of the legs of the V-shaped edge of each re-entrant flange. Accordingly, one leg of the edge ofa re-entrant flange will engage a corresponding ridge of a V-groove for approximately one-half the length of one of the legs of said groove. This is so because the particular V-shaped arrangement of the grooves permits the V-shaped edge of the re-entrant flange to enter the groove only for approximately onehalf its depth.
When a fastening element is secured, as with a nut 119 which is tightened, the sharp ridges of the groove will bite into the respective cooperating surfaces of the edge of the re-entrant flange, as illustrated in FIGS. 13, 14 and 15, and in effect will produce permanent deformations in said edges, as illustrated in FIG. 16. The extruded structural members A, B and C are formed of ductile metal and can be deformed by the fastening element 95 which is formed of a harder metal. The strength of each re-entrant flange has been so designed that the re-entrant flange will be deformed by the grooved head of the fastening element, the flange becoming somewhat flatened and assuming the general shape of V-grooves 99 and 101 of the head 96. As a result, the fastening element when tightened will be substantially permanently secured to a structural member and the normal resilience of the metal insures that the fastening element 95 will be maintained under tension so that inadvertent loosening of the same is unlikely to take place.
FIG. 1 illustrates a representative type of open structure utilizing each of the structural members, hereinbefore described, and demonstrates how such members may be employed in relation to each other and to conventional structural members. Referring to FIG. 1, the main vertical columms 121-124 of a bay are comprised of C-type members, said members being adapted to rest on concrete footings, not shown, and each being secured thereto by three angle brackets 125. Said brackets are attached to each of the three sides of the C-type members by fastening elements 95, each bracket being provided with two pairs of alined apertures and each pair of apertures being in registration with a respective longitudinal slot of the C-type member. As will be noted, the walls 67 of each of the C-type members are disposed exteriorly of the structure. The members 121-124 are joined attheir upper ends to horizontal B-type members 126-129 which are supported on brackets 131 secured to the inner faces of the members 121-124, each such face having two longitudinal slots 91 and 92. The brackets 131 are secured to the members 121-124 by fastening elements 95, the heads 96 of which are passed through the longitudinal slots and the shanks 97 passing through the apertures in the brackets 131. Each of the B-type members preferably is installed with the unbroken wall 48 uppermost.
It will be noted that assembly of the B and C-type members may be readily effected, since it is merely necessary to insert the fastening elements 95 in the re spective slots of said members and pass the same through the apertures provided in the brackets. Since registration of apertures in the adjacent cooperating structural elements is not required and since movement of any fastening elements in their receiving slots is readily accomplished, assembly of the parts is both simple and rapid.
Referring to FIGS. 1 and 19, additional A-type members 132 and 133, parallel to the B-t ype members 127 and 129, may be installed with angle brackets 140 which'are secured to the inner walls of members 126 and 128. As seen in F IG. 1, a plurality of transversely extending angle members 141 are secured in position, each by a pair of brackets 134 and v136 welded to the respective members, each bracket being secured to A and B-type members by fastening elements 95.
Members 126 and 128 may be braced by A-type members 143 and 144 which are disposed at a 45 angle between the members 121, 122 and 126 and are secured to respective members by straps 146 which are secured by fastening elements 95. An additional B-type member 147 is secured in parallel relation to the member 126 between the members 121 and 122 by brackets 148, in the same manner as hereinbefore described. Angle brackets 149 may be positioned on the members 147 and secured in any position anywhere along the length thereof. v
A truss structure consisting of parallel B-type members 151 and 152 joined by bracing straps 153 may be mounted intermediately of the members 121-124 and secured thereto by angle brackets 154, also in the same manner as hereinbefore described. It will be seen that the bracing straps 153 may be readily attached to the members 151 and 152 with fastening elements 95.
Referring further to FIG. 1, a plurality of A-type members 156 may be attached to a pair of fish plates 157, as illustrated, and the distal ends of said members may be attached to the members 121 and 122 by straps 158. The truss arrangement, as hereinabove described, may also be braced by angle straps 159 which extend from the members 122 and 123 to the underside of the truss construction, said straps being attached to the member 152.
The structure hereinabove described is merely representative of a variety of structures which may be erected rapidly and efficiently with the use of structural elements, in accordance with my invention. It should be noted that assembly of the parts requires a minimum of skill, since the conventional components such as straps, angle brackets, etc., are provided with apertures to receive the fastening elements and adjustment of the parts to facilitate assembly may be readily effected by sliding the fastening elements longitudinally of the slots to a desired correct position. Accordingly, it will be seen that with the use of my invention it is not required to alineapertures to receive the bolts or fastening elements in exact registration, as is conventionally required and, accordingly, considerable leeway is afforded to assemble cooperating parts.
It will be understood that various changes and modifications may be made from the foregoing without departing from the spirit and scope of the appended claims.
What is claimed is:
1. For use with an erector set assembly unit which includes a hollow structural member having a slot defined by re-entrant flanges in confronting spaced parallel relation, a T-bolt comprising a head and a threaded shank, said head having length and width dimensions greater than and less than the width of the slot in a hollow structural member, respectively, and a surface intersecting said shank, there being a pair of laterally undulating grooves in said surface extending parallel to the ends thereof, said grooves being V-shaped in transverse cross-section and double V-shaped in plan, the walls of said grooves defining a plurality of ridges which extend laterally thereinto, the lateral spacing of said grooves being equal to the lateral spacing of the reentrant flanges of said member, and the width of said grooves being equal to or greater than the thickness of said re-entrant flanges, whereby, said head may be inserted into said hollow member through said slot at any point along the length thereof and rotated to align said grooves with said flanges, there being a nut threadingly received on said shank, whereby, when said nut is tightened on said shanks, said ridges engage and laterally deform said flanges.
2. The T-bolt of claim 1 wherein said head is in the shape of a parallelogram in a plane perpendicular to said shank, said grooves extending generally parallel to the ends thereof.
3. An erector set assembly unit comprising a hollow extruded member having opposed first and second parallel walls and a single web portion perpendicularto and integrally connected to said walls midway between the distal edges thereof, each wall having an integral flange along each distal edge thereof, the respective distal edges of said flanges being co-planar and in spaced relation, a re-entrant flange integral with each said distal edge of said flanges, said re-entrant flanges being in confronting spaced parallel relation and defining therebetween longitudinally extending slots, a T- bolt having a head and threaded shank, said head having length and width dimensions greater than and less than the width of said slot, respectively, and a surface intersecting said shank, there being a pair of laterally undulating grooves in said surface and extending transversely thereof, said grooves being V-shaped in transverse cross-section and double V-shaped in plan, the walls of said grooves defining a plurality of ridges which extend laterally into said grooves, the lateral spacing of said grooves being equal to the lateral spacing of said re-entrant flanges and the perpendicular dimensions between the apexes of said ridges being equal to or greater than the thickness of said re-entrant flanges, said grooves engaging said edges of said re-entrant flanges, whereby, said head may be inserted into said hollow member through said slot at any point along the length thereof and rotated to align said grooves with 3 ,8 l 3 ,179 7 8 said re-entrant flanges, and a nut threadingly received in the shape of a parallelogram in a plane perpendicular on said shank, whereby, when said nut is tightened on t h k t said shank, the ridges laterally deform said re-entrant Sal s an Am grooves ex ending generally parallel flanges.
4. The assembly unit of claim 3 wherein said head is to the ends thereof.
Dated May 28, 1974 Column 1', Column 4, ColumnA, Column 4, .Column4, Column .6,
- (SEAL) Attest;
- The title should read: WITH AN ERECTOR SET ASSEMBLY UNIT--".
Inventor(s) Charles E Priest It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:
TITLE --FASTENING ELEBENT FOR USE SIPECIF."IICA'I'ION line line line line
. line line McCOY M. GIBSON JR. Attesting Officer.
7, "1969" should be ---l968--.
ll, "alined" should be ---aligned-=--==.
46, "flatened" should be -flattened=--. 59, "columns" should be -'columns-. 65, "alined" should be --=aligned---.
4, "aline" should be ---align--.
Signed and sealed this 26th day of November 19-7 C. MARSHALL DANN Commissioner of Patents FORM PO-IOSO (10-69) U.S, GOVERNMENT PRINTING OFFICE I969 0-366-334,
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|U.S. Classification||403/348, 411/971, 52/710, 403/353, 411/968, 411/84, 411/401|
|International Classification||E04B1/24, F16B37/04|
|Cooperative Classification||E04B2001/2496, E04B2001/2463, F16B37/045, E04B2001/2448, E04B2001/2415, Y10S411/971, E04B1/24, E04B2001/2475, E04B2001/2466, Y10S411/968|
|European Classification||E04B1/24, F16B37/04E|