Reinforcing And Supporting Saddle For C-shaped Sheet-metal Beams

Abstract

A saddle for supporting and reinforcing the central portion of a C-shaped sheet-metal beam on a transversely extending I-beam or other supporting structure in a building is disclosed. The saddle has a channel shape with a horizontal base or web and flanges extending upwardly from opposite edges thereof, the web providing a support for the bottom flange of the C-shaped beam on the upper surface of the I-beam or supporting wall, and the flanges being effective to reinforce the C-shaped beam against bending. One of the saddle flanges engages the web of the C-shaped beam to reinforce it against bending, and the other of the saddle flanges is employed to hold the bottom flange of the beam against movement out of supporting engagement with the web of the saddle.

Description

This invention relates, as indicated, to a saddle for reinforcing and supporting the central portion of a C-shaped sheet-metal beam.

BACKGROUND OF THE INVENTION

C-shaped sheet-metal beams, of a type fabricated by rolling from galvanized steel strip, have been proposed for use as joists and other purposes in residential building construction. When employed as joists, opposite ends of such beams are supported on the laterally spaced walls of a building in a manner similar to the support for the ends of 2 .times. 10 inch wooden planks commonly used as joists for this purpose. Where the distance between the walls of the building is sufficiently great, and single continuous joists are used to span this distance, the center portions of the joists are commonly supported on an I-beam or other supporting structure, such as the upper end of an intermediate partition wall. A support of this type at the center of the joist limits the load which can be carried by C-shaped beams, since the load concentration at this point will result in failure of the central portion of the beams.

OBJECTS OF THE INVENTION

One of the objects of this invention is to increase the load carrying capacity of the central portions of C-shaped sheet-metal beams at the points where they are supported on a transversely extending I-beam or the upper edge of an intermediate wall. A further object of the invention is to provide a saddle for mounting the central portion of C-shaped joists on an I-beam or other support, the saddle having provisions for reinforcing the C-shaped beam and for increasing its load carrying capacity.

A further object of the invention is to provide a reinforcing and supporting saddle of the character described which has a channel shape with a horizontal web for supporting the bottom flange of a C-shaped beam on a transversely extending and upwardly facing narrow supporting surface, a flange along one edge thereof for reinforcing the web of the C-shaped beam, and a connection along the other edge thereof for holding the bottom flange of the C-shaped beam against movement out of supporting engagement with the web or base of the saddle on which it is carried.

Another object of the invention is to provide a saddle of the type described above which can be fabricated readily by rolling galvanized steel strip, and can be assembled on the center portion of a C-shaped beam by workmen with a minimum of effort and without the necessity of special tools for this purpose.

Other objects and advantages of the invention will become apparent from the following description and the accompanying drawings, in which:

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a fragmentary perspective view illustrating the manner in which the sheet-metal saddles of this invention are employed to support and reinforce the central portions of C-shaped joists in a floor of a residential building;

FIG. 2 is an enlarged sectional view taken in the plane of the line II--II of FIG. 1;

FIG. 3 is a side elevational view looking from the right of FIG. 2;

FIG. 4 is an enlarged perspective view of the saddle shown in the preceding figures;

FIG. 5 is a transverse sectional view showing diagrammatically the manner in which the saddle of FIG. 4 is assembled on a joist to be supported thereby;

FIGS. 6 and 6a are diagrammatic views which illustrate the way C-shaped sheet-metal beams bend when subjected to loads sufficient to cause their failure;

FIG. 7 is a fragmentary perspective view of a modification of the invention;

FIGS. 8 and 9 are enlarged perspective views respectively of a fragmentary portion of the structure shown in FIG. 7, and of a spring clip which is used to connect a joist with the saddle on which it is supported; and

FIG. 10 is an enlarged fragmentary sectional view taken substantially along the line X--X of FIG. 7.

DETAILED DESCRIPTION

The saddle of this invention is designated as a whole by the numeral 1 FIGS. 1-5 of in the drawings, which show the manner in which it is used to reinforce and support the central portion 2 (FIG. 1) of a C-shaped beam 3 (FIGS. 1, 5, 6, 6a ) on a narrow upwardly facing surface 4 (FIGS. 1, 3, 4) of a structural support 5 (FIGS. 1, 3, 4,) that forms part of a building construction. This showing illustrates the preferred practice of the invention in which the beams 3 are employed as joists in the floor of a residential building, but it will be understood such showing is by way of example only and that the use of the saddles 1 to support similar C-shaped beams for other purposes, such as the rafters of a roof, is contemplated within the principles of this invention. When used as joists in a floor construction as shown in FIG. 1, the beams 3 are mounted in parallel positions with the opposite ends of each respectively supported on the upper ends of the spaced walls 6 (FIG. 1) of a building. The upwardly facing surface 4 may be the upper surface of a steel I-beam 5 as shown in FIG. 1, or the upper end of a partition wall between and parallel to the walls 6 (FIG. 1). Stiffeners 7, in the form of metal brackets as illustrated, or wooden nailer blocks, are inserted in the ends of the joists 3 as a reinforcement and to facilitate attachment of the joists 3 to boxing planks (not shown) about the perimeter of the building. After the joists 3 are in position, plywood decking 8 (FIG. 1) or other flooring may be secured thereto.

C-Beam 3

The beams 3 are preferably fabricated by rolling from galvanized steel strip, and are formed with a C-shaped contour as shown in the drawings. Each of the beams 3 is a channel that has a C-shape which is formed by a web 9 (FIGS. 2, 5, 6, 6a ) with parallel flanges 10 and 11 (FIGS. 2, 5, 6, 6a ) projecting outwardly from opposite edges thereof. Inturned lips 12 (FIGS. 2, 5, 6, 6a ) project inwardly toward each other from the outer edges of the flanges 10 and 11, the lips 12 being parallel to the web 9. One of the flanges 10-11 is preferably wider than the other to provide for assembly of two beams 3 in nested relation to conserve space and facilitate shipment.

Saddle 1

The saddles 1 are also fabricated by rolling from galvanized steel strip. Each is formed in the shape of a channel which includes a longitudinally extending web 13 (FIGS. 2, 4, 5) with parallel flanges 14 and 15 (FIGS. 2-5) projecting upwardly along opposite edges thereof. The flange 14 is a short flange and has a uniform height along its entire length. A lip or hook 16 (FIGS. 2, 4, 5) is turned angularly inwardly and downwardly from the upper edge of the flange 14 for hooking engagement over the upper edge of one of the beam lips 12 in a manner to be described.

The flange 15 is a longer flange which has a vertical dimension at its center 17 (FIGS. 3, 4) that is a substantial portion, approximately half, of the width of the web 9 of joist 3 for a purpose to be described. The length of the central portion 17 between the points 18 (FIGS. 3, 4) is approximately that of the width of the upper surface 4 of the beam 5. From the points 18, the upper edges 19 (FIGS. 3, 4) of the flange 15 slope downwardly to the ends 20 (FIGS. 3, 4) of the saddle 1, the ends 20 being spaced outwardly with respect to the opposite edges 21 (FIGS. 3, 4) of the supporting surface 4. Tabs 22 (FIGS. 1-5) are punched from the material of the center saddle portion 17 and project outwardly from the flange 15. The lower edges 23 of the tabs 22 engage the surface 4 and render the tabs 22 effective as gussets or buttresses to reinforce the flange 15 against bending. Tabs 24 (FIGS. 2, 3) are similarly struck from the material of the web 13 (of the saddle 1) and extend downwardly with respect to opposite edges 21 of the beam 5 as best shown in FIG. 3. When the saddle 1 is supported on the beam 5 in a centered position as shown in this FIG. 1, the tabs 24 are bent about the opposite edges 21 of the upper flange of the beam 5 to the positions shown in dotted lines in which they operate to hold the saddle 1 in a centered position with respect to the supporting surface 4.

The facing inner surfaces 25 and 26 (FIG. 5) of the flanges 14 and 15 of saddle are spaced apart a distance corresponding to the spacing between the oppositely facing outer surfaces 27 and 28 respectively on the lip 12 and web 9 of the beam 3 so that the lower flange 11 of the beam 3 will have a tight fit in the saddle 1 when assembled therein in the position shown in FIG. 2. The assembly of the saddle 1 on a beam 3 is effected by hooking the lip 16 on the saddle 1 over the lip 12 on the lower flange 11 of the beam 3 as shown diagrammatically in FIG. 5. After this has been done, the beam 3 is lowered to engage the saddle 1 with the surface 4 so that the weight of the beam 3 tends to rotate the saddle 1 in a clockwise direction about the upper edge 29 of the lip 12. After this has been done, assembly of the saddle 1 on the beam 3 is readily completed by applying a downward force to the upper flange 10, of the beam 3 which may be done by striking it sharply with a rubber mallet, to complete movement of the saddle 1 to the position shown in FIG. 2 of the drawings. In this position, the inner surface 26 of the flange 15 will snugly engage the outer surface 28 of the web 9 so that the flange 15 will reinforce the web 9 against bending when the beam 3 is subjected to heavy loads. In this position, the surfaces 27 and 25 have tight engagement with each other, and the upper edge 29 of the lip 12 is tightly engaged in the corner of the hook 16 so that the hook 16 operates through the lip 12 to hold the lower flange 11 of the beam 3 against movement out of engagement with the upper surface 30 of the saddle web 13.

Operation

In tests, the saddle 1 has been found to double the load which a C-shaped beam 3 will carry before failure of its central portion 2. Its action in this respect will be best understood by referring to the diagrammatic showings of FIGS. 6 and 6a which illustrate the manner in which a beam 3 will distort and fail when subjected to loads beyond its capacity. As the loading capacity is approached, the web 9 will bend initially as shown in dotted lines in FIG. 6, and the bottom flange 11 will flex upwardly, with a rotating action about the corner 31 between web 9 and flange 11 of beam 3 (FIG. 6) to the position also shown in dotted lines in which a substantial portion of the lower flange 11 is out of supporting engagement with the surface 4 (not shown in FIG. 6). As the load on the beam 3 is increased, the web 9 and flange 11 of the beam 3 are distorted further to the relative positions shown in FIG. 6a just prior to failure of the beam 3. The reinforcement for the web 9, of the beam 3 which is provided by the center 17 of the flange 15 of the saddle 1, holds the web 9 against bending, and this action is thus effective to prevent movement of the flange 11 of the beam 3 out of supporting engagement with the upper surface 4 on the I-beam 5. The hooking action of the saddle hook 16 is further effective through the lip 12 to hold the lower flange 11 of the beam 3 in engagement with the surface 4. The combined action of the saddle flange 15 and the hook 16 in this manner has been found to materially increase the load which the C-shaped beams 3 will carry before failure takes place. In contrast to the load which can be carried by a C-shaped beam without any reinforcement, the saddle 1 has been found to increase the load capacity of the beam approximately 112% before failure takes place. This compares with an improvement of approximately 57% in load carrying capacity by previous attempts to reinforce the central portion 2 (FIG. 1) of the beam 3 with different forms of bracing applied to the interior space in the beam 3 between its upper and lower flanges 10 and 11.

ALTERNATIVE EMBODIMENTS

The modification shown in FIGS. 7-10 eliminates the need for the hooking ledge 16 on the saddle flange 14, and substitutes therefor spring clips, respectively designated as a whole by the numeral 35, at spaced points along the length of the saddle 1 for holding the bottom flange 11 of the beam 3 snugly in supporting engagement with the upper surface 30 of the saddle web 13. As best shown in FIG. 8, each of the spring clips 35 has a V-shape which is formed by a pair of arms 36 and 37 which diverge angularly upwardly from an integral connection 38 (FIGS. 8-10) at the bottoms thereof. The arm 36 has a ledge 39 (FIGS. 8-10) at its upper end for hooking engagement over the upper edge 29 of the lower lip 12, and the arm 37 has a similar ledge 40 (FIGS. 8-10) which engages in an opening 41 (FIGS. 7, 9, 10) in the saddle short flange 14 with a snap action to hold the clip 35 against upward movement. The openings 41 are provided at intervals along the length of the saddle flange 14 corresponding to the locations of the clips 25. In this manner, the arm 36 and its ledge 39 are effective through the beam lip 12 of the beam 3 to hold the lower flange 11 of the beam 3 against moving out of engagement with the inner surface 30 on the web 13 of the saddle 1. In this modification, the web 13 of the saddle 1 has a width slightly greater than the width of the lower flange 11 of the beam 3 to provide a space 42 between the beam lip 12 and the saddle flange 14, as best shown in FIG. 10, to provide for insertion of the clip 35 to its operative position therebetween.

When used as joists in the construction of residential flooring, the beams 3 preferably have a size of about 7-1/2 .times. 2 inches. They may be rolled from galvanized steel having a thickness of, for example, either 10, 12, 14, 18 or 20 gage, according to the load to be carried thereby, 20 gage being preferred for the average residential construction. The saddles 1, in such case, are rolled from galvanized steel having a thickness of about 2 gage points heavier. For example, 16 gage steel is preferred for saddles 1 that are used with joists 3 that are fabricated from galvanized steel having a thickness of 18 gage.

As explained above, the saddles 1 furnish a reinforcing support for the central portions 2 (FIG. 1) of the joists 3 on the upwardly facing and transversely extending surface 4 of an I-beam 5 or other supporting structure. When mounted in position as shown in the drawings, the saddle 1 extends longitudinally of the joists 3 and has the bottom surface 16 (FIG. 3) of its base or web 13 in supporting engagement with the upwardly facing surface 4 of the beam 5, the upper surface 30 of its web 13 being in supporting engagement with the bottom flange 11 of the C-shaped joists 3. In this position of the saddle 1, attention is particularly directed to the fact that its longer flange 15 has supporting engagement with the web 9 of the C-shaped joist 3, and thus operates to reinforce the web 9 of the joist 3 against bending. In addition, attention is also directed particularly to the fact that the shorter flange 14 of the saddle 1, and the connection provided by the hook 16 (FIGS. 2, 4, 5) or the spring clips 35 (FIGS. 8-10), operate to hold the bottom flange 11 of the beam 3 against movement out of supporting engagement with the surface 30 of the saddle web 13, and consequently further act to reinforce the C-shaped joists 3 against bending under heavy loads. By reason of the opposite ends 20 (FIG. 4) of the saddles 1 extending beyond opposite edges 21 of the I-beam 5, it will be apparent that the saddles 1 act to reduce the concentration of the load on the beams over a greater length of their bottom flanges 11, and thus act to reinforce the joists 3 against downward bending about the opposite edges 21 of the beam 5. Because of the reinforcement of the joists 3 in these several respects, it will be apparent that the saddles 1 operate to increase the load which can be carried by the joists 3 without failure of the central portions 2 thereof.

While a preferred and modified embodiment of my invention have been shown and described, it will be apparent that adaptations and other modifications may be made without departing from the scope of the appended claims.

Claims

I claim:

1. In combination:

a. a structural support member having an upwardly facing surface;

b. a C-shaped beam having substantially parallel spaced beam flanges, a beam web connecting said beam flanges and a beam lip on one beam flange of said beam flanges;

c. a saddle having a saddle web, a saddle lip flange on one end of said saddle web, a reinforcing saddle flange on the other end of said saddle web and a saddle hook means on the free end of said saddle lip flange;

d. said saddle being operable so that said saddle hook means engages said free end of beam lip so that when relative pivotal movement occurs between said saddle and said free end of said beam:

1. the inner surface of said saddle web engages the outer surface of said one beam flange substantially along the registering said inner surface of said saddle web and said outer surface of said one beam flange to hold said beam lip against upward movement to said saddle web; and

2.

2. said inner surface of said reinforcing saddle flange engages the outer surface of said beam web substantially along the length of said reinforcing saddle flange in supporting engagement of said beam web to prevent bending of said beam web under heavy loads;

e. said saddle and said beam carried thereby having said saddle web mounted transversely to said upwardly facing surface of said structural support member; and

f. said saddle having ends spaced outwardly with respect to the opposite edges of said upwardly facing surface of said structural support member to

reinforce a central portion of said beam. 2. The combination recited in claim 1 and having:

a. the outer surface of said beam lip engaging the inner surface of said saddle lip flange substantially along the registering said outer surface of said beam lip and said inner surface of said saddle lip flange; and

b. a hook on the free end of saddle lip flange and engageable with said free end of said beam lip.

3. The combination recited in claim 1 and having:

a. a space defined between said beam lip and said saddle lip flange;

b. said saddle lip flange being provided with an opening; and

c. a spring clip having a first leg provided with a first ledge on its free end, and a second leg reliliently connected to said first leg and having a second ledge on its free end;

d. said spring clip being insertable into said space so that said first ledge engages the free end of said beam lip and said second ledge engages said opening to lock said beam lip to said saddle lip flange.

4. The combination recited in claim 1 wherein said saddle reinforcing flange has a saddle gusset projecting from said saddle reinforcing flange and in engagement with said upwardly facing surface of said structural support member to reinforce said saddle reinforcing flange against bending.

5. The combination recited in claim 1 wherein said saddle web has a pair of spaced positioning tabs projecting therefrom and engageable with said opposite edges of said upwardly facing surface of said structural support member to position said saddle on said upwardly facing surface.