US2840014A - Joint for a wooden truss - Google Patents

Description

J1me 1958 E. A. wADswoR'rH EIAL 2,840,014

JOINT FOR A WOODEN TRUSS 2 Sheets-Sheet 1 Filed Oct. 12, 1956 1NvENToR5 ATTORNEYSI PFVL 6- M KINLEY June 24, 1958 E. A. WADSWQRTH ETAL ,0

JOINT FOR A WOODEN TRUSS 2 Sheets-Sheet 2 Filed Oct. 12, 1956 IN VENTOR5 @404 6. M A IIVLEn yg wgzm ATTORNEY5 ice United States PatentQfi 2,840,014 JOINT FOR A WOODEN TRUSS Application October 12, 1956, Serial No. 615,71 2 i 7 12 Claims. Cl. 108-23) This invention relates to a joint in a wooden truss. More particularly, this joint incorporates theme of a sheet metal coupling member which embraces the sides of the members joined and secures the members in'a fixed position by fastening means impaling said structural ele:

ments.

More specifically, this invention relates to. ajoint for wooden truss members comprising a coupling as disclosed in our application Serial No. 358,239, of which this application is a continuation in part. 1 E

In constructing a wood frame roof for any type of building it has been customary to build up the roof of joists laid across the top plates and raftersbuilt up on i 1 the joists. Such a construction necessitates the use of skilled labor at each step of the construction and requires that relatively heavy framing lumber be used to give the roof requisite strength. It has been found, however, that by building the roof of preformed trusses, the same rr-greater strength than that obtained by the aforementioned constructionjis had, while effecting substantial savings in labor and material. The savings are'achieved by virtue of the fact that the preformed truss .can be constructedof lighter stock framing lumber, the trusses can be more widely spaced than are the joists and rafters, and the construction of the roof usingjpreformed trusses takes substantiallyless timethan is consumed by. bui1ding it up of joists and rafters.

In prior-preformed trusses, it has been customary to form joints by placing the members tobe'join'ed in sideby-side relation; drilling a hole through each of them, aligning the holes, and passing a bolt orjdowel through the aligned apertures. This effects a lap joint. Instead of bolts, -lag screws have been used to secure the structural elements in their side-'hy-side relation. In either case, a jointis formed'which is unsatisfactory for many reasons. First, trusses with such joints are awkward to handle because of the varying thickness of'the truss at the points of joining. Such diiferences in thickness are inevitable when thetwo joined members do not meet in the same plane but are merely lapped as above "described.

Secondly, the lapped joints as above described, are de- [ficient in that they are subject to eccentric moments and secondary bending, putting the wooden structural members to unusual and unnecessary stressr The instant invention presents a joint which makes it possible to expediently assemble structural elements of the trussesto realize advantages which are inherent in Briefly, the novel joint includes two or'more ri 2 1 members of substantially the same thickness, each of the structural members having parallel planar sides. The coupling member includes a'sheet metal device which is, in effect, two back-to-back channels. The members to be joined are introduced into opposite recesses in the coupling, with at least one of the structural members on each'side. Preliminary positioning means are provided on the web which comprises the center of the coupling, said preliminary positioning means impaling the struc tural members. A secure joint is formed as fastening means extending perpendicular to the side plates of the coupling member impale the sides of the structural members thereadjacent. a

Accordingly, it is an object of the instant invention to provide a joint for wooden structural elements wherein said structural elements may lie in a single plane;

A further object of this invention is to provide ajoint which may be efiected easily and quickly. 1 V

A further object of this invention is to provide ajo int which substantially contributes to the strength of the overall assembly. i 1

This invention embodies other novel features and details of construction and arrangement of parts which are hereinafter set forth in the specification and claims, and illustrated in'the accompanying drawings, wherein: p p

Fig. 1 is an elevational view of a -portion of a truss incorporating the instant invention; 1 j

'Fig. 2 is a perspective view of the coupling member which is part of the instant invention; s

Fig. 3 is an end elevational view of the coupling mem-. ber shown in 'Fig. 2, saidcoupling member being shown in use with wooden structural members comprising the .joint of the invention;

s Fig. 4 is an enlarged view of the heel of the truss in Fig.1; i N

Fig. Sis a bottom plan view of the heel of the truss in Fig.4; i 1

Fig. 6 is an enlarged view of portions of the truss shown inFigl; a, 3 Fig. 7 is a top plan view of the-ridge of the truss figures shown in Fig.6; and a e Fig. 8 is the perspective view of a modified form of the novel coupling member.

A typical truss 10 for use in constructing a woodroof of any type structure, utilizing the instant invention, comprises a lower chord 11 for-spanning the top plates 12 of the building wall (see Fig. 4). The upper chords 13 are joined to the lower chord 11' at'the heel 14 and run upwardly toward each other to' form the ridge 15, defining the inclined roof profile. The diagonals 16 and 17 are disposed intermediate the lowerchord 11 and the upper chord 13 to brace the truss. I e The strength of the truss depends upon effectively joining the structural elements to each other in a rigid assembly. This is accomplished by means of the joint of the instant invention. The joint includes a coupling member 20.

Member 20 includes a web 21 (see Fig. 2) and the side plates 22, 23,-24, and 25. The side plates; are formed on opposing edges of the web and extend'laterally thereof to opposite sides of the web. In the embodiment of the coupling member shown in Figs. 2 and 3, the side plates are integral with the web. On one .sideof the" web '21 the downwardly directed side plate 22 has a double thick- ,ness of material while the oppositely directed side' plate 23 ,is of a single thickness of material. .On thefopposite side. of the web 21, the upwardly directedside plate 24 has a double thickness ofv material and the oppositely directed side plate 25 has a single thickness of material.

The coupling member 20 is formed from a'flat strip of material; The web 21 is delinea'ted'on the strip of mateal and then reverse right angle bends are formed at each Patented June 24, 1958 side-of the'we'b. This sets up a side plate on each side of the web. At the extremity of each side of the plate thus set up the material is bent through 180? to provide a second thickness of material on the side plates 22 and 24, the extensions of which form'the side plates 23 and .25 respectively. The coupling member'thus formed as accomplished as shown inFig. 3 by bending the exten sions 23 and 25 inwardly of the web 21. 7 Only a slight deflectionis necessary to compensate for the thickness of the sheet metal. 1

In forming the joint, the coupling member 30' is laid on a structural element with the web 21 abuttinga face of the element. A nail hole 26 is provided adjacent each end of the web 21 for preliminarily locating and securing the coupling member with two nails on the one structural element. The side plates 22 and 25 embrace the structural element. The structural elements which are to be joined to the first structural element are located between the side plates 23 and 24 in abutting relation to the web 21. The side plates are each provided with the apertures 27 located at frequent intervals. It is desirable that the apertures on opposite side plates do not coincide. This obviates the possibility of fastener interference; that is,

of a nail associated'with one side plate hitting a nail from' the other side plate. With this aperture arrangement the coupling member can be secured to the structural elements with a suflicient number of nails to assure the requisite rigidity. p

In the truss member 10, the upper chord 13 is secured to the lower chord 11 by the coupling member 30,in the manner above described. The coupling member 30 is secured to each side of the lower chord 11 and the upper chord 13 by a plurality of nails 31. The corners32 of the coupling are folded under the lower chord 11 to be substantially flush therewith, and a nail 33 secures the corners in place on the lower chord. The web 34 of the made up of a pair of channel members 51 and 52. The channel member 51 has a web 53 and laterally directed side plates 54 and 55 extending upwardly from opposing edges of the web 53. The channel member 52 is similarly formed with a web 56 and laterally directed side plates 57 and 58. The channel rnern'bers 51 and 52 are joined with the webs 53and 56 arranged in opposing relationship and the channel member is spot-welded as at 59 along the seam on each side thereof. The side plates are provided with a plurality of apertures 60 for nails or other securing means, and the webs are provided with an aperture 61 at each end thereof for locating the coupling member and preliminarily nailing it to a structural element.

The invention has been described in a plurality of preferred embodiments. However, it is susceptible of modification within the scope of the invention and is well suited to many other uses than the one'described, which is merely exemplary. It finds utility in the prefabrication of all types of prefabricated wooden structural assemblies. The joint of the instant invention not only makes the prefabrication of such assemblies feasible, but contributes well to the strength thereof and at the same tirne'makingpossible a substantial reduction in time and labor costs of traditional structural assemblies. Accordingly, it is not intended that the invention be limited except as set out in the claims which follow:

We claim:

1. A wooden truss forsupporting a peaked roof, said trussincluding a horizontal lower chord having attached to its opposite ends inwardly and upwardly directed upper chord members, said upper chord members meeting in a peak, said upper and said lower chord members being of rectangular cross-section and of substantially the same thickness, each of said chord members having upper and lower surfaces and opposite side surfaces, the lower chord having opposite end surfaces, said opposite end surfaces being beveled in a plane parallel to the coupling member 30 lies intermediate the structural elements and is parallel to the upper'chord 13 at an angle to the lower chord 11. Diagonals 16 and 17 are similarly joined to the lower chord 11 by a coupling member 35 with a plurality of nails36 securing the structural elements to the coupling member 35; The base 37 of the coupling member 35 lies parallel to the lowerchord 11 and at an angle to the diagonals 16 and 17 intermediate these elements.

At the ridge 15 of the truss 10 the opposing upper chords 13 and the opposing diagonals 17 are joined by a coupling member 38. The web 39 of the coupling mem ber 38 is disposed vertically between the' opposing upper chord 13 and the opposing diagonal 17. As before, the coupling member is secured "to the respective structural elements by' nails 40, a suificient number of nails being chord 13 by the joint of this invention, but for purposes of economy, a'plate'42 is used, oneon each side of the truss. The plate 42 is secured to each of the structural elements by-a pluralityof nails 43, and in the presence of V the coupling 'members' at each of the other joints is of adequate strength for connecting the diagonal 16 to the upper. chord 13.

. In' Fig. 1 8, there is shown a modification of the cou} phngsas;describedaabovet 'llhe coupling member 50 is direction .of said adjacent upper chord member, said upper chord members at their meeting at said peak having adjacent end surfaces, the plane of said adjacent end surfaces substantially vertical, said chord members all lying in the same plane, said upper chords being joined at the peak and said upper chords each being joined to said lower chord at the opposite ends thereof by couplings, said couplings having a central web portion and parallel side plates disposed on and connected to opposite edgesiofsaid central web portion, said side plates extending perpendicular'to said web portion in either directionpin the joint at the peak, the vertical end surfaces of said' upper chords abutting opposite faces of said central web portion and said side plates extending along and contacting the opposite side surfaces of said upper 'chordsj and in the joint between the opposite end surfaces of said lower chord and said upper chords, the opposite faces, of said web portion of each of said couplings being abutted by the lower surface ofone of said upper chords upon one side and the end surface of said lower chord on the other side with said side plate portions extending along and contacting opposite side surfaces of said lower chords and'upper chords.

2. A wooden truss member as described in claim 1 wherein the side plate portions of said coupling memhers are apertured and fasteners extending through said apertures impale said chord members.

3. A wooden truss as described in claim 2 wherein the central web portion of said coupling members are provided with positioning means impaling said chord members. j

4. A wooden truss member as described in claim 3 wherein at least one of said side plate portions has a 'corner portion which'is bent over said chord portion which said side plate portion contacts.

5. A wooden truss member as described in' claim 1 wherein a pairof diagonal chords are incorporated into said diagonal chords extending from a point under said 7 peak to junction points on the lower chord intermediate the midpoint of said lower chord and said opposite ends of said lower chords, said junction points being on opposite sides of the midpoint of said lower chords respectively, each of said diagonal chordsbeing of rectangular cross-section and having an upper and a lower end, said lower end on each of said diagonal chords having a horizontal end surface and said upper end on each of said diagonal chords having a vertical end surface, said upper ends of said diagonal chord members extending into the coupling member at said peak and having their upper end surfaces abutting the opposite faces respectively of said central web portion of said coupling member at said peak, the side plate portions of said coupling at said peak extending along and contacting opposite side surfaces of said diagonal chord, fastening means extending through said side plate portions of said coupling at said peak impaling the diagonal chord members, an additional coupling at the lower end of each diagonal chord member, the lower end surface of each of said diagonal chord members abutting one face of one of said additional coupling members and the opposite face of said web portion abutting the upper side of said lower chord, said additional couplings having side plates which extend along and contact opposite sides of said diagonal chord members and said lower chord member respectively.

6. A wooden roof truss as described in claim wherein said additional coupling members have fastening means associated with their side plates, said fastening means on said additional coupling members extending into said lower chord and said diagonal chord members with which said additional coupling members are associated respectively.

7. A wooden truss as described in claim 5 having a second pair of diagonal chords the chords in said second pair extending one on either side of said truss, each of said chords in said second pair having, an upper end and a lower end, each lower end being associated with one of said coupling members on said lower chord associated with one of said first pair of diagonal chords, the upper end of each of said diagonals in said second pair being connected to the upper chord member adjacent.

8. A wooden truss for supporting a peaked roof, said truss including a horizontal lower chordhaving attached to its opposite ends inwardly and upwardly directed upper chord members, said upper chord members meeting in a peak, said upper and said lower chord members being of rectangular cross section and of substantially T the same thickness, each of said'upper chord members having upper and lower surfaces and opposite side surfaces, the lower chord having opposite end surfaces, said opposite end surfaces being beveled in a plane parallel to the direction of said adjacent upper chord members, said upper chord members at their meeting at said peak having adjacent end surfaces, the plane of said adjacent end surfaces substantially vertical, said chord members all lying in the same plane, the upper chords being joined at the peak and said upper chordsveach being joined to said lower chord at the opposite ends thereof by couplings, said couplings each comprising a sheet metal body having a rectangular central web portion in the interior of said body, and side plate portions integral with said web, the first of said side plate portions being bent in a first direction at right angles with respect to said web along one side thereof and then bent double in a'second direction opposite said first direction to provide a double thickness on a first side of the web and a single thickness on the second side of the web, and the second of the side plate portions being bent in said second direction along the opposite edge of said web and then bent double in said first direction to provide a 6 double thickness on said second side of said web and a single thickness on said first side, whereby the com posite body has one'side wall of double thickness and one of single thickness on either side of said web; in the joint at the peak, the vertical end surfaces of said upper chords abutting opposite faces of said central'web portion and said side plates extending along and contacting the opposite side surfaces of said upper chords; and in each joint between the end surfaces of said lower chord and said upper chords, the opposite faces of said web portion of each of said couplings being abutted by the lower surface of one of said upper chords upon one side and the end surface of said lower chord on the other side with said side plate portions extending along and contacting opposite side surfaces of said lower chord and upper chords.

9. A wooden truss for supporting a peaked roof, said truss including a horizontal lower chord having attached I to its opposite ends inwardly and upwardly directed upper chord members, said upper chord members meeting in a peak, said upper and said lower chord members being of rectangular cross section and of substantially the same thickness, each of said upper chord members having lower faces and opposite side surfaces, said lower chord member having opposite end faces, said opposite end faces being beveled in a plane parallel to the lower face of said adjacent upper chord members respectively, said upper chord members at their meeting at said peak having adjacent end faces, the planes of said adjacent end faces being parallel, said chord members all lying in the same plane, the upper chords being'joined at a joint at the peak and said upper chords each being joined at joints to said lower chord at the opposite ends thereof by couplings, the coupling at one of said joints having a rectangular central web portion and parallel side plate portions attached to the opposite edges of said web and perpendicular to said web; at said one joint the parallel faces of the joined cords abutting respectively opposite faces of said central web portion of said side plates extending along and contacting the opposite side surfaces of said joined chords.

10. A wooden truss for supporting a peaked roof, said truss including a horizontal lower chord having attached to its opposite ends inwardly and upwardly directed upper chord members, said upper chord members meeting in a peak, said upper and said lower chord members being of rectangular cross section and of substantially the same thickness, each of said upper chord members having lower faces and opposite side surfaces, said lower chord member having opposite end faces, said opposite end faces being beveled in a plane parallel to the lower face of said adjacent upper chord members respectively,

, said upper chord members at their meeting at said peak having adjacent end faces, the planes of said adjacent end faces being parallel, said chord members all lying in the same plane, the upper chords being joined at a joint at the peak and said upper chords each being joined at joints to said lower chord at the opposite ends thereof by couplings, the coupling at one of said joints comprising a sheet metal body having a rectangular central web portion in the interior of said body, and side plate portions integral with said web, the first of said side plate portions being bent in a first direction at right angles with respect to said web along one side thereof and then bent double in a second direction opposite said first direction to provide a double thickness on a first side of the web and a single thickness on the second side of the web, and the second of the side plate portions being bent in said second direction along the opposite edge of said web and then bent double in said first direction to provide a double thickness on said second side of said web and a single thickness on said first side, whereby the composite body hasone side wall of double thickness and one of single thickness on either side of said web; at said one joint the parallel faces of the joined" chords abutting. respectively opposite ,faces of said central'web portion and saidfside'j plates extending'along and 'contacting'the oppositeside surfaces of saidfjoined chords. 11.. A wooden truss for supporting a roof, said truss comprisingailower chord inemberand a plurality of upperjchord members, said chord members being. attached together adjacent their ends to'outli'ne a polygon,

each ,of, said chordmembers forming a side of said outlined, polygon, each of said chord meinbers being of rectangular cross section and of substantially the same thickncssyand-having upperand lower surfaces and opposite side surfaces, said lower chord having its Opposite and contacting the opposite side surfaces of said attached upper chords; and in the attachment of the lower chord to the adjacent upper chords, the opposite faces of said web portion being abutted respectively by the lower surface of said adjacent upper chord and the end surface of said lower chord with said side plate portions extending end surfaces beveled togparallel the lower surfaces of the r central web portion and said side plates extending along along and contacting opposite side surfaces'of said lower and upper chords. p

1 2. A wooden truss as described in claim 11 wherein each of said couplings comprise a sheet metal body having said rectangular web portion in the interior of said body and side plate portions integral with said web the first of said side plate portions being bent in a first direction at right angles with respect to said web along one side thereof and then bent double in a second direction opposite said first direction to provide a double thickness on a first side of the web and a single thickness on the second side of the web, and the second of the side plate portions being bent in said second direction along the opposite edge of said web and then bent double in said first direction to provide a double thickness on said second side of said web and a single thickness on said first side, whereby the composite body has one sidewall of double thickness and one of single thickness on either side of said web.

References Cited in the file of this patent UNITED STATES PATENTS 667,620 Eidlitz Feb. 5, 1901 1,355,657 vDryfoos Oct. 12, 1920 2,132,832 Prire Oct. ll, 1938 2,567,554 Davey Sept. 11, i

FOREIGN PATENTS 158,996 Switzerland Feb. 16, 1933 19,103 Denmark July 29, 1914

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