Metal roof truss

Abstract

A metal roof truss has a frame formed by metal frame members and a series of metal intermediate members secured at opposite ends to frame members by clinch locks. Each clinch lock is formed by forcing metal of one member through another member with consequent deformation of the other member to form a rivet-like projection.

Description

RELATED APPLICATION

[0001] This invention claims priority from U.S. Provisional Patent Application No. 60/219,135 filed Jul. 19, 2000.

BACKGROUND OF THE INVENTION

[0002] This invention relates to metal rood trusses which comprise a framework mountable on top of the walls of a building to support a roof.

[0003] Previously, pre-engineered and prefabricated roof trusses have conventionally been made of wood. Although attempts have been made to provide rooftrusses made of metal, for one reason or another, metal roof trusses have not proved to be very successful in practice.

[0004] It is therefore an object of the present invention to provide an improved metal roof truss.

SUMMARY OF THE INVENTION

[0005] According to the present invention, a metal roof truss has a frame formed by metal frame members and a series of metal intermediate members secured at opposite ends to frame members by clinch locks, each clinch lock having been formed by forcing metal of one member through another member with consequent deformation of the other member to form a rivet-like projection.

[0006] A metal roof truss in accordance with the invention can provide a very strong roof support which is easy to fabricate.

[0007] The frame may be of generally triangular shape and include a base member, a first side member extending from one end of the base member in an upwardly inclined direction, a second side member extending from the opposite end of the base member in an upwardly inclined direction to form an apex with the first side member, the intermediate members extending between the base member and a side member, each member having a C channel section with a bottom portion, side walls and inwardly extending flanges, the C channel sections of the base member and side members being directed in opposite directions to the C channel sections of the intermediate members, with the bottom portion of each intermediate member abutting the bottom portions of the base member and the side member and with the clinch locks being formed between abutting bottom portions.

DESCRIPTION OF THE DRAWINGS

[0008] One embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings, which:

[0009] FIG. 1 is a perspective view of a metal roof truss in accordance with the invention,

[0010] FIG. 2 is a rear view thereof,

[0011] FIG. 3 is a front view thereof,

[0012] FIG. 4 is a view on an enlarged scale of the rear of one of the connections of the roof truss as indicated by the circle 3 in FIG. 2,

[0013] FIG. 5 is a similar view of the front of the connection as indicated by the circle 5 in FIG. 2,

[0014] FIG. 6 is a sectional view of a clinch lock taken along the line 6-6 of FIG. 4, and

[0015] FIG. 7 is a sectional view of a clinch lock taken along the line 7-7 of FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0016] Referring to the drawings, a metal roof truss in accordance with one embodiment of the invention has a main frame of generally triangular shape including a metal base member 12, a first side member 14 extending from one end of the base member 12 in an upwardly inclined direction, and a second side member 16 extending from the opposite end of the base member 12 in an upwardly inclined direction to meet the side member 14 at an apex 18. The roof truss also has a series of metal intermediate members 20 extending between the base member 12 and one of the side members 14, 16.

[0017] The base member 12, side members 14, 16 and intermediate members 20 each have a C channel section, namely with a bottom portion 22, side walls 24,26 and inwardly extending flanges 28, 30 as shown in FIGS. 4 and 5. The C-channel sections of the base member 12 and side members 14, 16 are directed in opposite directions to the C channel sections of the intermediate members 20 so that the bottom portion 22 of the C channel section of an intermediate member 20 abuts the bottom portion 22 of the C channel section of the base member 12 and side member 14 or 16.

[0018] The bottom portion 22 of each intermediate member 20 is connected at one end to the bottom portion 22 of the base member 12 and at the other end to the bottom portion 22 of a side member 14 or 16 by clinch locks 40. In a clinch lock 40, as shown particularly in FIG. 6, the metal of the intermediate member 20 is forced through the frame member 16 to form a rivet-like projection 48. If desired, a transversely extending strengthening member 50 of C channel section may be provided at a connection as shown in FIG. 4 so that each clinch lock 40 holds three members together, see FIG. 7.

[0019] A metal roof truss in accordance with the invention provides an adequately strong structure which can be readily manufactured. Other advantages of the invention will now be readily apparent to a person skilled in the art from the foregoing description of a preferred embodiment. Other embodiments of the invention will also now be readily apparent, the scope of the invention being defined in the appended claims.

Claims

1. A metal roof truss having a frame formed by metal frame members and a series of metal intermediate members secured at opposite ends to frame members by clinch locks, each clinch lock having been formed by forcing metal of one member through another member with consequent deformation of the other member to form a rivet-like projection.

2. A metal roof truss according to claim 1 wherein the frame is of generally triangular shape and include a base member, a first side member extending from one end of the base member in an upwardly inclined direction, a second side member extending from the opposite end of the base member in an upwardly inclined direction to form an apex with the first side member, the intermediate members extending between the base member and a side member, each member having a C channel section with a bottom portion, side walls and inwardly extending flanges, the C channel sections of the base member and side members being directed in opposite directions to the C channel sections of the intermediate members, with the bottom portion of each intermediate member abutting the bottom portions of the base member and the side member and with the clinch locks being formed between abutting bottom portions.