The present invention relates in general to an apparatus and method for fabricating structural components. More particularly, this invention concerns an apparatus and method for assembling pre-cut members into trusses and joists.
Prefabricated building components, now widely utilized in the construction industry, are typically assembled at a manufacturing facility and then transported to the job site for incorporation into a building structure. Prefabricated trusses for use as roof or floor supports are assembled from pre-cut wooden chord and web members positioned in abutting relationship and connected together using toothed fastener plates.
Truss assembly devices have been developed for performing this task semi-automatically. The pre-cut wooden members are positioned manually over a support surface and clamped in place, after which connector plates are laid over the abutting joints. The connector plates are then embedded into the members with a gantry or other press to secure the joints on one side. The semi-complete truss is then turned over and similarly secured at the joints on the opposite side.
Various arrangements or truss tables in gantry presses have been employed in the truss assembly devices of the prior art. The prior truss assembly devices, however, have several shortcomings. The clamping methods utilized by the prior machines have been found inadequate in terms of adjustability, positive actuation and the like. In addition, the prior machines have been relatively slow in operation because movement of the trusses on the table during fabrication has been done primarily manually.
There exists a need for a new and improved truss assembly apparatus.
The invention is for a truss assembly apparatus and a method for assembling a truss utilizing the apparatus. The apparatus comprises a truss table having a work surface divided into a first and second assembly zone. The apparatus further includes first and second clamping assemblies for clamping the truss in the first and second assembly zones. The apparatus includes a flip-over assembly having a flip-over arm movable relative to the truss table for moving the truss from a first truss position in the first assembly zone, wherein a first truss face contacts the work surface, to a second truss position in the second assembly zone, wherein a second truss face contacts the work surface.
The flip-over arm is movable between a home position adjacent said work surface and an extended position, wherein the flip-over arm may be perpendicular to the work surface. In another alternative, at least a portion of the flip-over arm may extend over the second assembly zone when the flip-over arm is in the extended position. The flip-over assembly may comprise a plurality of movable flip-over arms for moving the truss from the first truss position to the second truss position.
The invention preferably includes a lift-out assembly having at least one lift-out arm movable relative to the truss table for moving the truss from the second truss position in the second assembly zone to a finished position spaced from the work surface. The finished position may be above and preferably extends beyond the work surface. The lift-out arm may comprise a plurality of lift-out arm rollers mounted thereon.
The work surface preferably has a plurality of assembly slots therein. The plurality of flip-over arms are aligned with the plurality of assembly slots to allow movement of the flip-over arms from home positions to extended positions. Similarly, the plurality of lift-out arms are aligned with the plurality of assembly slots to allow movement of the lift-out arms.
Flip-over actuators corresponding to the flip-over arms are positioned below the work surface and are interconnected between the truss table and the flip-over arms and are operable to move the flip-over arms. Similarly, the apparatus may include lift-out actuators.
Preferably, the first clamping assembly has a plurality of longitudinally spaced first moveable rails, spaces between the plurality of first moveable rails being aligned with the assembly slots. Similarly, the second clamping assembly preferably has a plurality of longitudinally spaced second moveable rails, spaces between the plurality of second moveable rails being aligned with the assembly slots. The first movable rails are each movable between a first rail home position, wherein the truss is free to move, and a first rail clamped position, wherein the first movable rails contact the truss when the truss is in the first truss position, and wherein the second movable rails are each movable between a second rail home position, wherein the truss is free to move, and a second rail clamped position, wherein the second movable rails contact the truss when the truss is in the second truss position. The first movable rails and the second movable rails are preferably adjacent when the first and second movable rails are in the first and second rail home positions.
Drawings of a preferred embodiment of the invention are annexed hereto, so that the invention may be better and more fully understood, in which:
Numeral references are employed to designate like parts throughout the various figures of the drawing. Terms such as “left,” “right,” “clock-wise,” “counter-clockwise,” “horizontal,” “vertical,” “up” and “down” when used in reference to the drawings, generally refer to orientation of the parts in the illustrated embodiment and not necessarily during use. The terms used herein are meant only to refer to relative positions and/or orientations, for convenience, and are not to be understood to be in any manner otherwise limiting. Further, dimensions specified herein are intended to provide examples and should not be considered limiting.
The invention is herein described with reference to the accompanying drawings and is not intended to limit the scope of the claimed invention, but is intended to describe particular embodiments to disclose the best mode of the invention to those skilled in the art.
The work surface 16 of the truss table 12 is defined by table plates 18a-j, which are arranged end-to-end. Table plates 18b-I provide working space for assembly of the trusses 20 and 22, while plates 18a and 18j provide staging areas for the table gantry press 14. The table may be designed to any desired length. The plates 18 are supported by a plurality of cross-members 24 which are mounted to the legs 26 of the table. Each leg 26 of the table 12 preferably includes a foot 28 threadedly attached thereto for height adjustment and leveling of the truss table 12 (best seen in
The table gantry press 14 straddles the work surface 16 of the truss table 12 and is supported to run along the length of the table. Gantry wheels 34, located in the gantry arms 36, roll along the gantry tracks 38, which are mounted to the truss table 12. A roller press (not shown) located in the gantry body 40 presses downwardly on the truss table 12 as the gantry press 14 passes along the table length.
Referring to
Two clamping assemblies 50 are mounted on each plate 18, as shown in
Turning to the clamping assembly in zone A, when the air cylinder 68 is in a retracted position, as in
Referring back to
Once the gantry press 14 has embedded the connector plates 46 into the trusses in zones A and C, the truss in zone C must be lifted out and removed from the table. The truss in zone A must be lifted out, turned over and placed in zone C for completion of the fabrication.
Movement of the trusses is accomplished with the truss movement assembly 80, seen in
The flip-over assembly 82 is located adjacent zone A and is attached to the lower surface of the truss table 12 by the truss movement assembly bracket 84. The flip-over assembly 82 comprises an elongate flip-over arm 86 which is connected at one end by a flip-over arm pivot mounting 88 to the movement assembly bracket 84 adjacent the lower surface of the table 12. A flip-over arm bracket 90 pivotally connects the flip-over arm 86 at a point removed from the flip-over pivot mounting 88 to one end of the flip-over actuator 92. In the preferred embodiment, the flip-over actuator is an air cylinder 92 having one end pivotally connected to the movement assembly bracket 84 and the rod end 94 connected to the flip-over arm bracket 90.
While the truss 20 is being assembled and pressed, the flip-over assembly 82 is in a home position 87, as seen in
Prior to the actuation of the flip-over arm 86, the movable inner jigs 52 are brought to their home position at the center of the table. With the inner jigs so arranged, abutting one another, the area of zone B, evident when the braces are clamping the trusses as in
The lift-out assembly 100 is positioned adjacent zone C and is attached to the truss movement assembly bracket 84 which is mounted to the table 12 below the work surface 16 as shown. The lift-out assembly 100 comprises a lift-out arm 102 and a lift-out actuator assembly 104. The lift-out arm 102 is seen in its home position 103 in
The lift-out actuator assembly 100, in the preferred embodiment, comprises a lift-out actuator, such as the air cylinder 106, pivotally connected at one end to the movement assembly bracket 84 and pivotally attached at the other end to the lift-out power arm 108. In the preferred embodiment, the actuator is an air cylinder, but other actuating devices may be employed. The rod end 110 of the air cylinder 106 is pivotally attached to the lift-out power arm 108 through the cylinder bracket 112. The lift-out power arm 108 is pivotally mounted to the movement bracket 84 at one end and pivotally attached to the lift-out arm 102 at the other end through the power arm bracket 114. Similarly, the support arm 116 is pivotally connected to the movement assembly bracket 84 at one end and to the lift-out arm 102 at the other end through a support arm bracket 118. When the air cylinder 106 is actuated, the rod end 110 extends outwardly, pivoting the power arm 108 which in turn lifts and laterally moves the lift-out arm 102. The support arm 116 acts to raise and laterally move the lift-out arm in conjunction with the power arm to the extended position. Actuator assemblies other than the described system may be used without departing from the spirit of the invention.
Preferably, the lift-out arm 102 has a plurality of rollers 120 connected thereto to assist the user in moving the truss 22 off of the lift-out arm 102. The lift-out arm 102 also preferably has a stop block 122 attached to the lift-out arm 102 at its innermost end. The stop block 122 prevents the truss from rolling from the rollers 120 onto the truss table 12.
The truss assembly apparatus described herein is preferably for use in fabricating wooden trusses and joists, although other applications may be obvious to those skilled in the art.
In utilizing the truss assembly apparatus 10, precut wooden truss members 42 and 44 are arranged in zone A of the truss table 12 on the working surface 16. Simultaneously, a semi-finished truss 22 is positioned in zone C. The clamping assemblies 50 are actuated, moving the inner jigs 52 outward toward the outer jigs 54 and clamping the trusses 20 and 22 between the jigs. End stops and other devices known in the art may be added to assist in the proper arrangement of the truss members. Connector plates 46 are placed over the joints between the truss members in both zones A and C and are usually manually tapped into the wood so that they will hold their positions during pressing. The gantry press 14 moves along the length of the table embedding the connector plates 46 into the wood. The clamping assemblies 50 are returned to their original home positions 74 such that the jigs are no longer clamping the trusses. In the home positions, the clamping assemblies preferably have little or no space between them in zone B, at the center of the table. This is, in part, accomplished by positioning the jig actuators 68 below the table surface 16. The lift-out assemblies 100 are then actuated to move the lift-out arms 102 into extended positions 105, that is, to move the lift-out arms upwardly through the assembly slots 78 from below the table surface 16 and engage the truss 22 thereby raising it out of zone C and moving it toward the outer rails 32 of the table. Preferably the lift-out arm 102 include rollers 120 and move in the extended position 105 to extend over the outer rails 32 for ease of removal of the truss 22 from the truss table 12. The lift-out arm 102 may also include stop blocks 122 to prevent the truss 22 from rolling off the lift-out arms 102 the wrong direction. The lift-out arms 102 are lowered back into position under the table surface 16. The flip-over assemblies 82 are then activated. The flip-over arms 86 are rotated from a home position 74 under the table surface to an extended position 76, engaging the truss 20 and lifting it from zone A while simultaneously rotating it along its longitudinal axis L. The flip-over arms 86 deposit the truss 20 in zone C with the connector plates 46 facing downward. The flip-over arms 86 are then returned to their home positions 74. The order of the steps may vary without departing from the spirit of the invention. The process may be repeated as desired.
This application claims the benefit of the filing date of co-pending Provisional Application Ser. No. 60/104,035, filed Oct. 13, 1998 by David L. McAdoo and Michael C. Rosser entitled “TRUSS FABRICATION METHOD AND APPARATUS,” the disclosure of which is incorporated herein by reference in its entirety for all purposes.
Number | Date | Country | |
---|---|---|---|
60104035 | Oct 1998 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 09416862 | Oct 1999 | US |
Child | 10964894 | Oct 2004 | US |