US20080172983A1

US20080172983A1 - System and method for the automated assembly of trusses

Info

Publication number: US20080172983A1
Application number: US12/018,471
Authority: US
Inventors: James F. Urmson
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-01-23
Filing date: 2008-01-23
Publication date: 2008-07-24

Abstract

The present invention relates to systems and methods used to assemble trusses composed of wooden components. The system comprises at least one station for cutting lumber into truss components (i.e., cords and web members), a station for position the cord members relative to one another, a station for positioning the web member relative to the cord members for attachment, and a station for securing the web members to the cord members and/or other web members in a predetermined sequence.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit under 35 U.S.C. §119(e)(1) of the Jan. 23, 2007, filing date of U.S. Provisional Application No. 60/886,147, the entirety of which is incorporated by reference herein.

BACKGROUND OF THE INVENTION

This invention relates to systems and methods used to assemble trusses. More specifically, the present pertains to the automated assembly of trusses composed of wooden components.
A typical truss 10 fabricated from wooden components is illustrated in FIG. 1, and includes cord members 11A, 11B that form a perimeter of the truss 10, and web members 12 disposed between and secured to the cord members 11A, 11B. Although some stages of the fabrication of trusses may be automated, the overall process remains labor intensive. In the fabrication of the truss 10, raw material, i.e., uncut lumber components, are cut to desired lengths, and edges of the components are trimmed for assembly. Automated saw systems are used to cut the truss components, including the cord members 11A, 11B and web members 12. Such a saw system is disclosed in U.S. application Ser. No. 11/096,634. The linear movement of the lumber through a cutting path, and the vertical, rotational and linear movement of a saw is automated and governed by a controller, which may include a computer with one or more processors and a database.
In larger manufacturing facilities, the specifications of the trusses to be manufactured are entered into the controller of the saw system including data such as the total number of trusses, the total number of each truss component, the length of each component and the angle of the ends of the components. The controller may be programmed to cut all the components of a single truss or component by component. In such a case the components are bundled then taken to an assembly station where the trusses are manually assembled. First, the cord members 11A, 11B are assembled to form the perimeter. Thereafter, the web members 12 are positioned between the cord members 11 and secured thereto in order from left to right, or from right to left. These steps take a considerable amount of manpower and time. Presently, there does not exist a system or method for the automated assembly of a truss.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevational view of a truss as is known in the art;

FIG. 2 is a top schematic view of a system for the automated assembly of a truss;

FIG. 3 is a perspective view of an assembly table with the cord members positioned for assembly;

FIG. 4 is a perspective view of vector cams mounted for movement on an assembly table;

FIG. 5 is a perspective view of a vector cam having a register and rollers;

FIG. 6 is an exploded view of a vector cam and the components thereof;

FIG. 7 is a perspective view of a vector cam positioned adjacent the apex of the truss.

FIG. 8 is a perspective view of the vector cam of FIG. 7 repositioned to engage the truss on the other side of the apex of the truss.

FIG. 9 is a perspective view of the vector cam of FIG. 7 engaging the truss on the other side of the apex of the truss.

FIG. 10 is a top schematic view of cord members entering the assembly area of the assembly table.

FIG. 11 is a top schematic view of clamping devices engaging and advancing cord members on the assembly table.

FIG. 12 is a top schematic view of an assembly table with the clamping devices and roller guides repositioning the cord members on the assembly table.

FIG. 13 is another top schematic view of an assembly table with the roller guides repositioning the cord members on the assembly table.

FIG. 14 is a perspective view of an automated press for affixing connector plates to cord members and web members of the truss;

FIG. 15 is an front plan view of the automated press alignment system showing the automated press mounted on an overhead rail for back and forth movement of the automated press;

FIG. 16 is a front plan view of the automated press showing the upper and lower platen sections with panels removed;

FIG. 17 is a perspective view of a robotic arm retrieving connector plates from a plate bin adjacent an automated press;

FIG. 18 is a perspective view of the robotic arm of FIG. 17 moving two connector plates from the plate bin to the automated press;

FIG. 19 is a rear perspective view of a base portion of a compartment of a plate bin;

FIG. 20 is a cross-sectional view of a compartment of the plate bin showing the pushing assembly for pushing connector plates from the central column to the front cavity;

FIG. 21 is a front perspective view of a base portion of a compartment of a plate bin;

FIG. 22 is a front perspective view of a base portion of a compartment of a plate bin showing connector plates in a central column and an empty front tray;

FIG. 23 is a front perspective view of a base portion of a compartment of a plate bin showing connector plates in a front tray;

FIG. 24 is a perspective view of a web presenter picking up a web member from a web conveyor;

FIG. 25 is a perspective view of a web presenter characterizing an end section of a web member through a sensor mounted on a vertical post;

FIG. 26 is a perspective view of a web presenter placing the characterized web member on an assembly table for pickup by a main robotic arm;

FIG. 27 is a plan view showing the board to be characterized by sensors mounted on vertical posts;

FIG. 28 is a plan view showing the determination of the leftmost point or edge of a web member by a vertical post having a sensor;

FIG. 29 is an exploded plan view of the left sensor detecting the leftmost point or edge of a web member;

FIG. 30 is an exploded plan view of the left sensor detecting a second leading edge of a web member;

FIG. 31 is a plan view showing the determination of a rightmost point or edge of a web member by a vertical post having a sensor;

FIG. 32 is an exploded plan view of the right sensor detecting the rightmost point or edge of a web member;

FIG. 33 is an exploded plan view of the right sensor detecting a second leading edge of a web member;

FIG. 34 is a plan view of a web member showing the location of measured points on the web member;

FIG. 35 is a top plan view showing a robotic aim placing a web member in between cord members in accordance with one aspect of the present invention;

FIG. 36 is a perspective view of a main robotic arm having clamping members and staple guns; and

FIG. 37 is a perspective view of a large gantry press for securing connector plates to a truss.

DETAILED DESCRIPTION OF THE INVENTION

The features of the invention believed to be novel are specifically set forth in the appended claims. However, the invention itself, both as to its structure and method of operation, may best be understood by referring to the following description and accompanying drawings.
Exemplary embodiments of the present invention solves the problems in the art by providing a system, method, and computer software code, for improving operating capabilities of a automated truss assembly system. Persons skilled in the art will recognize that an apparatus, such as a data processing system, including a CPU, memory, I/O, program storage, a connecting bus, and other appropriate components, could be programmed or otherwise designed to facilitate the practice of the method of an exemplary embodiment of the invention. Such a system would include appropriate program means for executing the method.
An embodiment of the present invention for a system 13 and method for the automated assembly of trusses is shown in the schematic of FIG. 2 and includes a plurality of workstations. The system 13 comprises a first station 14 that has one or more automated saw systems 17 for cutting truss components such as cord members 11A, 11B that make up a perimeter of a truss 10, and one or more automated saw systems 18 for cutting the web members 12 that are disposed between, and secured to the cord members 11A, 11B. A second station 15 includes an assembly table 20 where the cord members 11A, 11B are staged or readied for assembly, positioned relative to one another for assembly of the truss 10, and then secured to one another. In addition, at the second station 15 the web members 12 are secured to the cord members 11A, 11B. A third station 16 includes an automated system for presenting and positioning the web members 12 relative to the cord members 11A, 11B on the assembly table 20 in order from left to right, or from right to left. The above descriptions and the dotted lines in FIG. 2 identifying different workstations are for purposes of example only, and are not intended to limit the scope of the invention. In any of the embodiments described herein, one or more workstations may be provided for assembling a truss in accordance with the present invention.
The system 13 is particularly useful in the assembly of large numbers of trusses. For example, a single job may require the assembly of as many as one hundred trusses or more. In such cases, the trusses are assembled in the order in which the trusses will be loaded onto a truck. In an embodiment, the system may include one or more of a plurality of controllers. Each of the controllers are incorporated in the assembly system and are programmed with a specification to control the assembly of a plurality of trusses. In addition, the controllers are programmed with a specification to cut, stage and/or assemble a total number of trusses 10 that includes a total number of cord members 11A, 11B and web members 12 to complete the job. Further, the controllers may be programmed to identify each truss 10, cord member 11 and/or each web member 12 in the order in which they are to be cut and assembled and may monitor the production of the trusses 10 so that one may determine the number of trusses 10 assembled at any time during production.
In an embodiment, the system includes eight controllers. More specifically, there are one or more controllers, such as controllers 28 and 29, for the automated saw systems 17,18, a main controller 30, a controller 31 for web presenter 90, controller 104 for the main robotic arm 101, controllers 41, 44 for the presses 71A, 71B. The databases of controllers 28 and 29 include data relative to the dimensions of the truss components including the length and width of a component, and the angle of cut to be made at either end of a component. The saw systems 17 and 18, in response to appropriate input commands, cut the cord members 11 and web members 12 respectively according to the entered data. It is contemplated that communications delivered to any of the controllers of the system may be directed to the particular controller directly or indirectly through the main controller 30.
The database of main controller 30 in the second station 15 includes a specification, including data, associated with the position of cord members 11A, 11B, i.e., the angle, relative to one another. In addition, the main controller 30 may include a specification, including data, relative to where a web member 12 is positioned on the truss 10 including a point or points where a web member 12 is attached to cord members 11A, 11B and an angle at which a web member 12 is disposed relative to the cord members 11A, 11B. The main controller 30 may be linked to any one or more of the other controllers by Ethernet or any other suitable method of communication known in the art for providing communication between one or more of the other controllers to the main controller 30.
With respect to the embodiment shown in FIG. 2, the saw systems 17, 18 are of the type disclosed in the patent application, U.S. application Ser. No. 11/096,634 that was published on Oct. 5, 2006, U.S. Patent Pub. No. 2006/0219073 A1, the entirety of which is incorporated herein. In addition, the saw systems 17, 18 including the below described automated feeders, conveyors and roller tables are sold by TCT Manufacturing, Inc. located in Mount Dora Fla.
The saw systems 17, 18 include an entrance roller table 24 and an exit roller table 25 that have a plurality of rollers rotatably mounted on a frame. In this manner, a work piece such as a piece of lumber can be linearly fed into and out of a cutting zone in each of the saw systems 17, 18. In the first station 14, pieces of lumber 23, 27 are placed on automated feeders 22 and 26, which have a plurality of rotating belts or chains mounted to a frame and rotate in a direction perpendicular to the linear movement of the lumber 23, 27 on the roller tables 24 of the saw systems 17, 18 respectively.
The operation of the saw system 17 relative to the first station 14 and the second station second 15, and components therefore, are now described in more detail. The saw system 17 is used to cut the cord members 11A, 11B. Pieces of lumber 23, taken from lumber carts 40 are placed on the feeder 22, which transports the lumber to entrance roller table 24 and into a cutting zone of the saw system 17. As described above, the controllers are programmed to generate a signal identifying the particular truss, i.e., the first truss, to be built, which truss includes a predetermined number of top cord members 11A and a predetermined number of bottom cord members 11B. In addition, one or more signals are generated that are indicative of the position of a saw blade (not shown) relative to the lumber; and, the saw system 17 cuts the cord members 11A and 11B responsive to the signals and in accordance with the data that represents the dimensions of a cord member 11A, 11B.
The example of the truss 10 shown in FIG. 1 has a triangular perimeter and includes two top cord members 11A and two bottom cord members 11B. However, the system 13 is not so limited and may be used to assemble other types of truss configurations including, but not limited to, a rectangular truss wherein the top cord member 11A is positioned parallel relative to a bottom cord member 11B.
In the embodiment described herein, the controllers are programmed so the bottom cord members 11B are cut first before the top cord members 11A are cut. However, the order in which the cord members 11A and 11B may depend on the location of the saws 17, 18 relative to the assembly table 20. Indeed, as described in U.S. Provisional Application No. 60/886,147, which is incorporated by reference herein, the top cord members are cut prior to the bottom cord members. After the lumber 23 is cut, the cord members 11A, 11B exit the cutting zone on the exiting roller tables 25 and are transported to the assembly table 20 via conveyors 19A and 19B. Optionally, a splicer 32 may be positioned next to the conveyor 19A to fasten the two bottom cord members 11B to one another and the top cord members 11A to one another for assembly of the truss 10 in the second station 15. The fastening step is intended to maintain the cord members 11A and cord members 11B in abutting relationship during assembly. In addition, the top cord members 11A are moveable with respect to one another to form the apex 122 of the truss 10. Connector plates 72, as will be described in more detail, are pressed onto the truss 10 later in the assembly process to affix the cord members 11A and 11B together.
Again with respect to FIG. 2, a plurality of transfer chains 33 are operatively associated with the conveyor 19A and the assembly table 20 to transfer the cord members 11A, 11B from the conveyor 19A to the assembly table 20. The transfer chains 33 may be characterized as a component of the first station 14 or second station 15. The operation of the transfer chains 33 with the conveyor systems is known to those skilled in the art and includes a chain or belt supported on a frame and one or more sprockets. The transfer chains 33 are disposed between spaced apart rollers (not shown) on the conveyor 19A and spaced apart rolling pins 36 on the assembly table 20. One or more hydraulically or pneumatically driven cylinder systems and servomotors (not shown), operatively connected to the controller 28 (and/or 30) and transfer chains 33, control movement of the transfer chains 33 between a first position, below the conveyor 19A and assembly table 20, and a second position above the conveyor 19A and assembly table 20.
A sensor 35 is positioned toward an end of the conveyor 19A and is in communication with a controller 28-30 and servomotors (not shown) to detect the presence of an approaching cord member 11A, 11B. The controllers 28, 30 and/or sensor 35 have a processor (not shown) that is programmed to activate the servomotors and transfer chains 33 when a cord member 11A, 11B is detected at a predetermined distance from the sensor 35 or an end of the conveyor 19A. The transfer chains 33 are disposed in a first position below the conveyor 19A as the cord members 11A, 11B travel along the conveyor 19A. When activated, the transfer chains 33 are elevated between consecutive rollers on the conveyor 19A, engaging the cord members 11A and transferring the cord members 11A to the assembly table 20.
With respect to the bottom cord members 11B, when the controller 28 or 30 signals the transfer chains 33 to be elevated, the controller 28 or 30 is programmed to maintain the transfer chains 33 in the second or elevated position a predetermined time which is sufficient for the bottom cord members 11B to travel along the transfer chains 33 until the bottom cord members 11B fall off the transfer chains 33 at a predetermined location of the assembly table 20. Alternatively, a second sensor (not shown) is positioned on the assembly table 20 that detects the presence of the bottom cord member 11B and generates a signal. The controller 28 or 30, in response to this signal and/or after a predetermined amount of time has elapsed, is programmed to lower the transfer chains 33 to cause the bottom cord members 11B to fall off an end of the transfer chains 33 and onto the assembly table 20.
Similarly, with respect to the top cord members 11A, when the controller 28 or 30 signals the transfer chains 33 to be elevated, the controller 28 or 30 is programmed to maintain the transfer chains 33 in the second or elevated position for a predetermined amount of time which is sufficient for the top cord members 11A to travel along the transfer chains 33 until the top cord members 11A fall off the transfer chains 33 at a predetermined location of the assembly table 20. Alternatively, a second sensor (not shown) is positioned on the assembly table 20 that detects the presence of the top cord member 11A and generates a signal. The controller 28, in response to this signal and/or after a predetermined amount of time has elapsed, is programmed to lower the transfer chains 33 to cause the top cord members 11A to fall off an end of the transfer chains 33 and onto the assembly table 20.
The assembly of cord members 11A, 11B in the second station 15 is described now in more detail. The top cord members 11A and bottom cord members 11B, as shown in FIGS. 3 and 10, are positioned on the assembly table 20. In an embodiment, the assembly table 20 comprises the plurality of rolling pins 36 mounted on support members 37 (shown in FIG. 3) and spaced apart along the table 20. In the embodiment shown in FIG. 3, the rolling pins 36 are spaced apart on the table 20 and are driven by a motor and belt assembly 38 to deliver the cord members 11A, 11B along the assembly table 20. After the cord members 11A, 11B are positioned on the table 20 as described above, the controller 30 activates the one or more motors so the rolling pins 36 begin to rotate on the assembly table 20 to advance the cord members 11A, 11B toward the assembly area on the assembly table 20.
With respect to FIG. 10, the cord members 11A, 11B are spaced apart on the assembly table 20 and aligned using vector cams 21A, 21B on the assembly table 20. When the cord members 11A, 11B advance on the assembly table 20, the vector cams (clamping devices) 21A, 21B and roller guides 42A, 42B grip and/or engage the cord members 11A, 11B and advance them on the assembly table 20 for assembly of the truss perimeter and truss 10.
A vector cam (clamping device) 21A or 21B is illustrated in more detail in FIGS. 4 and 6-8. Referring to FIG. 4, exemplary vector cams 21A are positioned on the table 20 between consecutive spaced apart rolling pins 36. The clamping devices 21A, 21B are mounted on, and moveable on tracks 45 that are supported on a steel frame 46. The clamping devices 21A, 21B and roller guides 42A, 42B include a carriage 47 positioned in mating relationship with the tracks 45. More specifically, the track 45 has a gear-like configuration with consecutive teeth 59 and grooves 60. Wheels 61 are mounted on axles 62 secured to the carriage 47 and are disposed in mating relationship with the track 45. The wheels 61 comprise spaced apart circular plates 63 with pins 64 disposed between the plates 63, which pins 64 are annularly spaced about the axle 62. The pins 64 are positioned relative to the track 45 so that the pins 60 are in mating relationship with the grooves on the track 45 so the carriage 47 moves as the wheels 61 rotate. In addition, the pins 64 preferably rotate so that any sawdust generated during the assembly process will not collect in the grooves 60. Such a wheel and track assembly may be purchased from the Nexen Group, Inc. Vadnais Heights, Minn., for example.
As shown in FIG. 6, the back and forth movement of the carriages 47 is controlled in part by a servo-driver 65 operatively connected to the controller 30. The controller 30 identifies where the truss 10 is in the assembly process including the position of where the truss 10 is on the table 20 and the orientation of the cord members 11A, 11B relative to one another. The controller 30 generates a signal that is representative of a location (direction and distance) of where the carriage 47, including clamping mechanisms and/or rollers thereon, relative to an end of the track 45 and an angle at which the components (described below) are disposed relative to cord members 11A, 11B. Responsive to this signal, the servo-driver 65 is activated to drive the carriage 47 a predetermined distance and direction on the track 45 and assembly table 20.
Referring to FIG. 6, details of the vector cam 21A or 21B are disclosed. An arm 48 is mounted to an underside of the carriage 47 and supports the vector cams and rollers. More specifically, the vector cams 21A, 21B include a rotating register 49 and rollers 50 to engage, guide, move and/or position the cord members 11A and 11B on the assembly table 20. A servomotor 51 is operatively connected to the register 49 and is programmed via the controller 30 to rotate the register 49 in predetermined increments to position cord members 11A and 11B on the assembly table 20 for receiving web members 12 at predetermined locations relative to the cord members 11A and 11B. The rollers 50 are passive rollers and do not act to advance the cord members 11A, 11B, but serve as a guide maintaining the linear or angular position of the cord members 11A, 11B on the assembly table 20.
As is particularly shown in FIG. 6, the register 49 is mounted on a shaft 66 that is connected to the servomotor 51 for rotation of register 49. The shaft 66 is inserted through a bearing 67 that is mounted to an end of the arm 48, and into the servomotor 51, which engages the shaft 66. The mounting plate 52 that is fitted over the bearing 67 is mounted to an electric clutch 68 that is disposed between the bearing 67 and servomotor 51. When activated, the clutch 68 engages the servomotor 51 so the plate 52 pivots in the same direction and at the same time the register 49 rotates. When the clutch 68 is deactivated, the clutch 68 disengages from the servomotor 51 and the register 49 continues to rotate advancing a cord member 11A, 11B on the assembly table 20.
With respect to FIGS. 5-6, the rollers 50 (or position of the rollers 50) are horizontally adjustable back and forth relative to the register 49 and mounting plate 52. The vector cams 21A, 21B are equipped with a pneumatic cylinder assembly including the block 53, piston 54 and guide rods 55 and operates to position the rollers 50 relative to register 49 and cord members 11A or 11B. Such an assembly, and operation thereof, is known to those skilled in the art. For example a company, Sintered Metal Corporation, located in Japan manufactures and sells such pneumatic cylinder assemblies. The position of the rollers 50 on the block 53 may also be manually adjusted. The block 53 has slots 69 in which adjustment nuts (not shown), and bolts 70 securing the rollers 50 to the block 53 in which the bolts 70 are threaded. The bolts 70 are simply loosened within the nuts so the rollers 50 can slide back forth on the block 53.
As shown in FIG. 4, a cable carrier system 57 is supported on track beam 58 mounted to the frame 46, and supports and protects cables or wires connecting the controller 30 to components of the vector cams 21A, 21B. An example of such a cable carrier system is sold under the brand name IGUS®, which is sold by Igus, Inc. located in East Providence, N.J.
The roller guides 42A, 42B have similar components as the above-described vector cams 21A, 21B. Accordingly, the description of above vector cams 21A, 21B applies to the roller guides 42A, 42B, with the exception that the roller guides 42A, 42B do not include the register 49 or the electric clutch 68. In addition, the rollers 50 on the roller guides 42A, 42B are positioned on the cylinder block 53 to engage an outside edge of the cord members 11A, 11B, as shown in FIG. 3. The rollers 50 on the vector cams 21A, 21B engage an inside edge of the cord members 11A, 11B, and the register 49 engages the outside edge.
The operation of the vector cams 21A, 21B and roller guides 42A, 42B in positioning the cord members 11A and 11B on the assembly table 20 is now discussed in more detail in reference to FIGS. 3 and 10-13. In the embodiment shown in FIG. 3, the system 13 includes four vector cams 21A, 21B (two each for the top cord members 11A and bottom cord members 11B respectively) and four roller guides 42A, 42B (two each for the top cord members 11A and bottom cord members 11B). However, the system 13 may contain more or fewer of each of the vector cams 21A, 21B and roller guides 42A, 42B.
At the outset, when the entire system 13 is started to assemble trusses 10, each of the controllers 28, 29, 30 is programmed to identify each truss component used to assemble a truss 10, and each truss 10 that has been assembled. Accordingly, as the cord members 11A and 11B are staged on the assembly table 20 as described above, the vector cams 21A, 21B are aligned with the cord members 11A, 11B for receiving cord members 11A, 11B as the rolling pins 36 advance the boards.
With respect to FIG. 10, the vector cams 21A, 21B are illustrated in an open position with the pneumatic cylinder assembly biasing the passive rollers 50 away from the register 49. Each of the four vector cams 21A, 21B is equipped with a sensor 56, such as a through-beam sensor or a limit switch, to detect the presence of a cord member 11A or 11B. When the sensor 56 detects the cord member 11A or 11B, the controller 30 generates a signal in response to which the vector cam 21A, 21B closes against the cord member 11A or 11B as shown in FIG. 11.
In an embodiment of the invention, the bottom cord member 11B is advanced along the assembly table 20 before the top cord member 11A, because the angle at which the top cord member 11A is positioned relative to the bottom cord member 11B, and the position of the vector cams 21A and roller guides 42A on the track is based on a point of origin 113 taken from an edge of the bottom cord member 11B as shown in FIG. 10. A through beam sensor 110 is mounted to the assembly table 20 between the vector cams 21A, 21B and roller guides 42A, 42B. When the through beam sensor 110 detects the presence of the bottom cord member 11B, a signal is sent to controller 30 that generates a signal responsive to which the registers 49 stop rotating. The registers 49 then reverse their rotation to back the bottom cord member 11B a predetermined distance.
The top cord members 11A are then advanced so the registers 49 on the vector cams 21A, 21B begin rotating. With respect to FIG. 1, the truss 10 has a triangular configuration, so the position of the top cord members 11A relative to one another and relative to the bottom cord members 11B is adjusted to form the triangle. The controller 30 is programmed to identify the particular truss 10 being assembled and the controller 30 includes a database that includes data representative of the dimensions of the truss member 10, including but not limited to the angles at which the top cord members 11A are disposed relative to one another and relative to bottom cord members 11B.
When the sensor 56 (through-beam sensor) detects the presence of the top cord member 11A, a signal is generated and sent to the controller 30, which identifies the board as a top cord member 11A. The controller 30 generates one or more signals in response to which the registers 49 stop rotating and reverse rotation to back the top cord member 11A a predetermined distance. In addition, the one or more signals are indicative of a position/angle of each vector cam 21A on the assembly table 20 relative to a position the top cord members 11A. Responsive to these signals, the mounting plate 52 and rollers 50 on vector cams 21A and roller guides 42A pivot with respect to the arm 48 to position the top cord member 11A at a predetermined angle with respect to the bottom cord member 11B. As shown in FIGS. 12-13, the vector cams 21A and roller guides 42A move on the track 45 in the direction indicated by arrows A to account for the angled position of the top cord member 11A.
In addition, as shown in FIG. 13, the mounting plate 52 and rollers 50 on the roller guides 42A rotate with respect to arm 48 to a predetermined angle relative to the bottom cord member 11B. As the top cord member 11A advances on the table 20, the roller guides 42A engage the top cord member 11A to maintain the top cord member 11A in position relative to the other cord members 11A, 11B and web members 12 as the truss 10 is assembled. Similarly, the roller guides 42B are positioned to engage the bottom cord member 11B; however, typically the bottom cord member 11B is disposed substantially horizontally. Therefore, the mounting plate 52 and rollers 50 are not pivoted to a predetermined angle as roller guides 42A.
As mentioned above the controller 30 is programmed to identify each truss 10 that is being assembled including identifying each cord member 11A, 11B and web member 12 that is used in the assembly process. To that end, the controller 30 includes data that represents particular tasks that must be performed and the order in which such tasks must be performed. In addition, the controller 30 records the performance of each task.
The data input into the controller 30 or recorded by the controller 30 also includes data representative of where the truss components 11A, 11B and 12 are to be positioned relative to one another (and/or relative to the point of origin 113 as referred to herein) and/or relative to one or more reference points on the assembly table 20. In addition, the data also includes data relative to the position of the system components such as the vector cams 21A, 21B, guide rollers 42A, 42B, presses 71 (described below) and robotic stable guns 230 (described below) or other components, relative to the truss components 11A, 11B and 12, and/or relative to one or more reference points on the assembly table 20. Accordingly, the controller 30 is programmed to generate signals representative of the position of the system components on the assembly table 20 necessary to perform a particular task. Once that task is performed, the controller 30 generates signals necessary to reposition certain components as necessary to perform a subsequent task.
By way of example, and in reference to FIG. 10, once the top cord member 11A is positioned at a predetermined angle relative to the bottom cord member 11B, the controller 30 generates signals that are representative of a predetermined distance that the corner (or point of origin 113) of the truss 10 must be advanced on the table 20. After the truss 10 is advanced, robotic staple guns 230, which are explained in detail further below and are shown in FIG. 36, for example, are positioned on the table 20 to staple the corners of the top cord member 11A and bottom cord members 11B together.
After the components 11A, 11B are stapled together, the truss 10 is advanced on the table a predetermined distance where a press 71A, 71B (described below) is positioned to attach connector plates 72 to the corner of the truss 10. After the connector plates 72 are affixed to the corner of the truss 10, the truss 10 is advanced a predetermined distance so a web member 12, as shown in FIG. 38, may be positioned between and stapled to cord members 11A and 11B. After this task is performed, the truss 10 is advanced a predetermined distance to a position on the assembly table 20 where the presses 71A, 71B are positioned to affix connector plates 72 to the web member 12 and cord members 11A, 11B, thereby securing the web member 12 in place.
As the truss 10 advances on the table 20, the roller guides 42A and vector cams 21A are repositioned on the table 20 to maintain the top cord member 11A in its predetermined position relative to the bottom cord member 11B. As shown in FIG. 7, the vector cam 21A, for example, will eventually reach an apex 122 of the truss 10 wherein the vector cam 21A or roller guide 42A is positioned on a first top cord member 11A′, and must be repositioned to engage a second top cord member 11A″.
As shown in FIG. 8, responsive to one or more signals from controller 30, the vector cam 21A opens and disengages the first cord member 11A′. The arm 48 then pivots downward removing the register 49 and rollers 50 from the path of travel of the truss 10. In this way, the arm 48 is movable from a first position where the register 49 and/or plurality of rollers 50 engage a cord member to a second position where the register 49 and/or plurality of rollers 50 do not engage the cord member 11A″. The truss 10 then advances on the table 20 so the vector cam 21A will engage the second top cord member 11A″. The mounting plate 52, register 49, and rollers 50 pivot with respect to the arm 48 (either simultaneously with or after the arm 48 pivots downward) to the same angle the cord member 11A″ is disposed relative to the bottom cord member 11B.
As shown in FIG. 9, the arm 48 is then pivoted upward such that the rollers 50 and the register 49 engage the second top cord member 11A″. When activated, the rollers 50 will rotate to advance the truss 10 on the table 20. It is contemplated that as the apex 122 moves down the assembly table, the remaining vector cams 21A, 21B and roller guides 42A, 42B will undergo similar repositioning as described with respect to FIGS. 7-9.

Operation of Presses to Affix Connector Plates to the Truss

In connection with the assembly of trusses using the present system, an automated press 71 is provided that moves back and forth on the assembly table 20 to affix connector plates 72 to the truss 10 to secure the web members 12 to cord members 11A, 11B or to affix cord members 11A and/or 11B to one another. With respect to FIG. 14, there is illustrated an embodiment of an automated press 71 for use in the assembly of a truss 10. An embodiment of the invention may include two presses 71A and 71B on opposed sides of the assembly table 20 to affix connector plates 72 as needed to any truss 10. In one embodiment, the press 71A affixes connector plates 72 to top cord members 11A and web members 12 and the press 71B affixes connector plates 72 to the bottom cord members 11B and web members 12 as shown in FIG. 2.
As shown in FIG. 14, exemplary press 71A includes an upper or top platen 73 that is supported on a press frame 74 and spaced above a lower or bottom platen 75 supported on the press frame 74. Both the top platen 73 and bottom platen 75 may include a magnet or are otherwise magnetized for engaging and installing the connector plates 72 on a truss 10. In addition, both the upper platen 73 and the lower platen 75 are configured for movement relative to one another.
As shown in FIG. 14, and in detail in FIG. 16, each of the upper platen 73 and the lower platen 75 are welded to a post 76 that is housed inside a spring 78. The posts 76 and springs 78 are operatively connected to a pneumatic cylinder 80 for raising or lowering either one of the upper platen 73 and lower platen 75 with respect to the other of the upper platen 73 and lower platen 75. Pneumatic cylinder 80 includes a compressed air source (not shown) and a piston 83 for driving the upper platen 75 downward toward lower platen 73 or lower platen 73 upward toward upper platen 75. Springs 78 allow the upper platen 75 or lower platen 73 to return to a home or resting position after the platens 73, 75 affix web members 12 to cord members 11A, 1B as described below. The pneumatic cylinder 80 may be used to separate the connector plates 72 when two connector plates are placed on the lower platen 73 or to aid in retracting the platens 73, 75 after the connector plates 72 are pressed onto a particular truss 10. Additionally, the presses 71A, 71B may include one or more hydraulic cylinders as are known in the art for providing the pressing force needed to press connector plates 72 and affix connector plates 72 to the truss 10 to secure the web members 12 to the cord members 11A, 11B or cord members 11A and/or 11B to one another.
In addition, the presses 71A, 71B are mounted for back and forth lateral movement on an overhead rail 124 for positioning the presses 71A, 71B relative to a truss 10 to attach connector plates 72 to the truss 10. The presses 71A, 71B are mounted on the overhead rail 124 and the presses 71A, 71B are positioned adjacent the assembly table 20. To enable lateral movement of the presses 71A, 71B on overhead rail 124, presses 71A, 71B each include a press alignment system 126.
As shown in FIG. 14, and more particularly in FIG. 15, the press alignment system 126 includes opposed upper frame portions 128, which may be C-shaped members 129 as shown and connected to the frame 74 of the press 71A or 71B. Each upper frame portion 128 or C-shaped member 129 includes a disc 130 mounted by a shaft 132 to opposed plates 133 on opposed sides of the C-shaped member 129. The disc 130 includes an annular groove 138 that extends around a circumference of the disc and is rotatably maintained on the overhead rail 124 on a lower track 140 on I-beam member 144. As shown in FIGS. 14-15 by exemplary press 71B, the presses 71A, 71B may include a plurality of C-shaped members having a disc 130, shaft 132, and plates 133 to enable smooth back and forth movement of the presses 71A, 71B on I-beam member 144.
In addition, each upper frame portion 128 includes a servo-driver 146 for driving the disc 130 and presses 71A, 71B forward and backward on overhead rail 124 as described below. Specifically, servo-driver 146 includes a rotating spindle 148 and a wheel 149. The wheel 149 has having a plurality of spaced apart circular plates 151 with pins 150 disposed between the plates 151 that engages a track 158 (similar to track 45) that extends longitudinally adjacent a center of the I-beam member 144.
As shown in FIG. 14, to enable overhead movement of the presses 71A, 71B on overhead rail 124, overhead rail 124 includes the I-beam member 144 mentioned above that has a center wall 152 for dividing the I-beam member 144 into a left side 154 and a right side 156. Each of the left side 154 and right side 156 includes the track 158 that has a gear-like configuration with consecutive teeth 160 and grooves 162 and a lower track 140 for rotatably mounting disc 130. Driven by the servo-driver 146, the pins 150 of the wheel 149 are adapted to mate with the teeth 160 and grooves 162 of the track 158 to move the presses 71A, 71B laterally backward and forward on the I-beam member 144 along with the simultaneous directional rotation and movement of disc 130. The presses 71A, 71B can be moved back and forth to be in position to affix connector plates 72 to permanently attach web members 12 to cord members 11A, 11B.
The back and forth movement of the press 71, lateral movement of the bottom platen 75, and vertical (up/down) movement of the top platens 73 is triggered by trip switches in communication with the servo-driver 146, pneumatic cylinders, and controllers 30, 41, or 44 that control or manage movement of the presses 71A, 71B and press components. The controller 30 identifies where the truss 10 is in the assembly process including the position of where the truss 10 is on the table 20. More specifically, the controller 30 has a database having data stored that is representative the number of each size connector plate 72 to be placed on a given truss 10 and the location of where each connector plate 72 is positioned on each truss 10.
As described in more detail below, two robotic arms 85, each disposed adjacent a respective press 71A, 71B transfers connector plates 72 from a bin assembly 86 to the presses 71A, 71B for installation. The robotic arm 85 is mounted on a base 87 and takes connector plates 72 from the bin assembly 86 as shown in FIG. 17 and rotates to move the connector plates 72 toward top platen 73 and bottom platen 75 of the press 71A. Specifically, the robotic arm 85 will first move the connector plates 72 to the lower platen 75 of the press 71. When the press 71 is ready to receive connector plates 72 for installation on a truss 10, the robotic arm 85 has a magnet 88 for engaging connector plates 72 in the bin assembly 86. Typically, the robotic arm 85 takes two connector plates 72, including a top connector plate 72A and a bottom connector plate 72B, and positions the connector plates 72A, 72B on the bottom platen 75, with the bottom connector plate 72B magnetically engaged on the bottom platen 75. One suitable source for a robotic arm 85 of the type described herein, which may be modified as desired, is the Fanuc Robot LR MATE 200ib robotic arm.
Subsequently, the top platen 73 lowers and engages the top connector plate 72A and then the top platen 73 is raised holding the top connector plate 72A spaced above the second connector plate 72B, which remains on the bottom platen 75. The controller 30, 41, or 44 then generates a signal that is indicative of a location on the truss 10 where the connector plates 72A, 72B are to be affixed to the truss 10, or the signal may be indicative of the distance the press 71A or 71B must travel on the overhead rail 124. Responsive to this signal, the servo-driver 146 drives the press 71A, 71B into position for attachment of the connector plates 72A to the truss 10. The top platen 73 and bottom platen 75 stamp the connector plates 72A, 72B into place on the truss 10.
The balance springs 78 may be positioned on the press 71A to support the bottom platen 75 such that when the top platen 73 is lowered, the springs 78 adjust the bottom platen 75 upward to engage the truss components. In this manner, the truss components are not depressed downward below a plane of the assembly table 20 when the press 71 installs the connector plates 72, which may cause the truss components to misalign. After installing the connector plates 72A, 72B, the press 71 returns to a position adjacent to the robotic arm 85 for receiving two more connectors 72A, 72B. The robotic arm 85, and associated hardware and software that can perform the functions as described herein, are commercially available through ABB Robotics and/or Nachi Robotics, model number VSO5E/LE-02.
These robotics contain programmable controllers and processors that control movement of the arm. The main controller 30 is linked to the robotic arm 85 to generate a signal indicative of an instruction for the robotic arm 85 to retrieve a connector plate 72 from the bin assembly 86. The controller 30, includes a database that represents the total number of connector plates 72 used to complete a particular job including the total number of each size connector plate 72, the order in which each connector plate 72 shall be retrieved from the bin assembly 86 and the coordinates (x,y,z) at which each connector plate 72 is located relative to an end of the robotic arm 85 and the ground. The controller 30 indexes or counts the connector plates 72 as they are retrieved from the bin assembly 86 in order to identify the subsequent plates 72 to be retrieved. The assembly of a truss 10 typically requires several different sizes of connector plates 72. For example, the smaller connector plates 72 may range in size from 3″×4″ to 6″×6″. Accordingly, several bins 166 may be arranged to account for different size connector plates 72.
Now referring to FIGS. 17-23, the structure and operation of the bin assembly 86 in conjunction with the robotic arm 85 and presses 71A, 71B will be discussed in more detail. Bin assembly 86 comprises a base portion 164 supporting a plurality of bins 166 thereon. Bins 166 include a bottom tray 168 having a rear portion 170, a central column 172 having a central columnar cavity 174 with retention bars 176 for maintaining a stack of connector plates 72 therein, and a front tray portion 178. The front tray portion 178 is sized to fit two or more connector plates 72 therein. In one embodiment, the bin assembly 86 includes an interconnecting rail 165 that extends around an upper perimeter of the bin assembly 86 and interconnects the plurality of bins at an upper portion of the bins.
In addition, to enable the bin assembly 86 to hold a large number of connector plates 72, yet make a small number of connector plates 72 available for simple pick up by the robotic arm 85, the bin assembly 86 includes a pushing assembly 180 for making two or more connector plates 72 readily available in the front tray portion 178 of a bin 166 for easy pickup of the connector plates 72 by the magnet 88 of the robotic arm 85. As shown in FIGS. 19-23, pushing assembly 180 includes a pneumatic cylinder 182 (that is disposed between the bottom tray 168 and the base portion 164), a piston 184, and an engagement member 186.
The pneumatic cylinder 182 is operably connected to an actuating mechanism 188 disposed at the front tray portion 178 by two or more lines 190. As shown in FIG. 19, the pneumatic cylinder 182 may be of a double acting cylinder type, having two ports (not shown): one for outstroke and one for instroke of the piston 184. As shown in FIGS. 20-21, the actuating mechanism 188 includes a push-button 192 or like structure that, when contacted or otherwise activated, actuates a two way valve (not shown) as is known in the art for allowing air into one of two or more ports to move the piston 184 that is in contact or connected to the engagement member 186 in a forward or backward direction. The backward or forward movement of the piston 184 in turn causes backward or forward movement of the engagement member 186.
In addition, as shown in FIG. 19, in one embodiment, the rear portion 170 of the bottom tray 168 of bin 164 includes a longitudinal slot 194 extending from a point adjacent an end of the rear portion 170 toward the front tray portion 178. The engagement member 186 is slidably mounted within the longitudinal slot 194 and moves forward and backward within the longitudinal slot 194 of the rear portion 170 of the bin 166 to push two or more connector plates 72 from the central column 172 to the front cavity 178 of the front tray portion 178. For this reason, in one embodiment, the engagement member 186 includes a top extent 196 and a front face portion 198. The top extent 196 is sufficiently long such that when the engagement member 186 pushes two or more plates 72 towards the front tray portion 178 of the bin 166, the remaining connector plates 72 in the central column do not tilt or otherwise impede the movement of the two or more bottommost connector plates 72 being pushed into the front tray portion 178.
When the controller 30 generates a signal indicative of an instruction for the robotic arm 85 to retrieve a connector plate 72 from the plate bin 86, robotic arm 85 first triggers the actuating mechanism 188 of a predetermined compartment of the plate bin 86 by contacting push-button 192 for a sufficient time so as to activate the actuating mechanism 188. As a result of activation of the actuating mechanism 188, air may be delivered to one of the two ports from a suitable compressed air source through air lines 190 to move the piston 184 in a forward direction. Since the piston 184 is secured to the engagement member 186, the piston 184 will cause the engagement member 186 to move from its resting position in a forward direction shown by arrow C in FIG. 20 to push two or more of the bottommost connector plates 72 from the central column 172 into the front tray portion 178. Thereafter, air will enter into the other of the two ports to allow the piston 184, and thus the engagement member 186, to move back to a resting position. This process can be repeated each time two or more connector plates 72 are required for securing cord members 12 to web members 11A and 11B.

Presentation of Web Members for Assembly of Truss

Third station 16 includes an automated system 200 for presenting and positioning the web members 12 relative to the cord members 11A, 11B on the assembly table 20 in order from left to right, or from right to left. As shown in FIGS. 24-26, the automated system 200 for presenting web members 12 includes a conveyor 19B, a web presenter 90, and vertical posts 106 having laser sensors 107, 108 disposed in front of the conveyor 19B.
The web presenter 90, shown in FIGS. 24-26, may be a robotic arm that is equipped with a programmable controller to identify which member and truss are located on the web assembly table 20, and the precise location thereof. One suitable source for a robotic arm 90 of the type described herein, which may be modified as desired, is the Fanuc Robot R-2000 iB robotic arm.
With respect to FIG. 24 particularly, the web presenter 90 is illustrated grasping a web member 12 off of the conveyor 19B of the second station 15. The web member 12 cut by second saw system 18 will be picked up by the web presenter 90, which may be a robotic arm, and later presented on the assembly table 20 for pickup by a main robotic arm 101 for placement of the web member 12 within cord members 11A, 11B of a corresponding truss 10. The movement of the web presenter 90 is controlled in part by a controller that is operatively connected with the web presenter (robotic arm) 90.
The second saw system 18 is linked with a controller 29 and is programmed to cut the web members 12 in the order in which the web members 12 are to be attached to the cord members 11A, 11B. The cut web members 12 exit a cutting zone of the second saw system 18 onto the linear conveyor 19B, which transports the web members 12 down the conveyor 19B. The system 18 includes a sensor 94 positioned toward an end of conveyor 19B. The sensor 94 detects the presence of a web member 12 on the conveyor 19B when a web member 12 reaches a predetermined distance from the sensor 94 or end of the conveyor 19B. When a web member 12 is detected a predetermined distance from the end of the conveyor 19B, the sensor 94 generates a signal indicative of the presence of a web member 12, which signal is received by the saw controller 29. The saw controller 29 is in communication with the motor and belt assembly 38 and signals the motor and belt assembly 38 to stop. At the same time, the sensor 94 conveys a signal to controller 30 or 104 for the robotic arm 90 to pick up the web member
The controller 31 is programmed to identify the particular web member 12 including the length of the web member 12. As explained above, each of the controllers is programmed to include a database that includes data representative and associated with each web member 12, including the dimensions of the web members 12 or cord members 11A, 11B, and the order in which the components are cut, staged and assembled. Accordingly, as the web members 12 are cut, staged and assembled, the controller 31 counts or identifies each web member 12 as it is staged and presented for assembly.
When the sensor 94 detects the web member 12, a signal is generated and sent to the controller 31. In tun, when the controller 31 receives the signal from the sensor 94, the controller 31 identifies the web member 12 including the length of the web member 12. The controller 31 is able to calculate the rate of speed the web member 12 is traveling on the conveyor 19B. Based on this calculation the controller 31, also having data relative to the length of the web member 12, determines the time at which the web presenter 90 will be activated to verify the identity of the web member 12, adjust a position of the web member if necessary, and present the web member 12 to the assembly table 20 for pickup by the robotic arm 101. The web member 12 is positioned on assembly table 20 such that the robotic arm 101 will pick up the web member 12 at a predetermined location of the web member 12 as will be discussed in detail below.
Prior to the robotic arm 101 engaging the web member 12, the web presenter 90 may perform functions that assure the web member 12 is positioned at the appropriate coordinates for presentation to the robotic arm 101. In an embodiment, as shown in FIGS. 24-33, vertical posts 106 that support laser sensors 107 characterize dimensions of the web member 12 as will be set forth below. Posts 106 include slots 109 therein and a receiving block 112 having an opening therein for receiving respective ends of the web member 12 and for detection of the web member 12 by the laser sensors 107, 108.
With respect to FIGS. 24-33, the measurement and positioning/centering of a web member 12 on the assembly table 20 for pickup by the robotic arm 101 is illustrated. The controller 31 has data relative to the length of the web member 12 and determines the time at which the web presenter 90 must be activated to first verify the presence of a particular web member 12, identify a staple center of the web member, and present the web member 12 to the assembly table 20 for pickup by robotic arm 101.
First, the web presenter 90 grasps the web member 12 at or adjacent a center of the web member as shown in FIG. 24 using a suction platen 202. Second, as shown in FIG. 25, and more closely in FIGS. 28-29, the web presenter 90 (not shown in FIGS. 27-33 for purposes of clarity) is moved a particular distance to the left such that the leftmost point or first leading edge 204 of the web member 12 can be detected by the leftmost sensor 107 on the left vertical post 106. The controller 31 monitors the movement of the robotic arm relative to the sensor 107. For example, when the servomotor 104 moves the web presenter 90 to the left, it generates one or more signals to the controller 31 representative of the distance that the robotic arm has moved. Thereafter, as shown in FIG. 30, the web presenter 90 continues to move the web member 12 leftward and stops when the sensor 107 senses a second leading edge 206 of a left side 205 of the web member 12. Again, once the second leading edge 206 is detected, the controller 31 determines the distance the robotic arm has traveled.
Once the two leading edges 204, 206 for the left side of the board have been detected, the controller 31 causes the web presenter 90 to move rightward to likewise determine a first leading edge 208 and second leading edge 210 on the opposed right side 211 of the board. As shown in FIGS. 31-32, a first leading edge 208 of a right side of the web member is detected by the rightmost sensor 208. The controller 31 monitors the movement and position/location of the web presenter (robotic arm) 90 relative to the sensor 108. Thereafter, as shown in FIG. 33, the web presenter (robotic arm) 90 moves rightward to determine the second leading edge 210 of the right side of the particular web member 12. Again, one the second leading edge 210 is detected, the servomotor 104 generates one or more signals to the controller 31 representative of the distance that the robotic arm has moved.
From the information gathered by the sensors 107, 108, the controller 31 can verify that a length 212 of the web member 12 between the first leading edges 204, 208 and a length 214 between the second leading second leading edges 206, 210 match the data for the web member 12 in the controller 31. If so, the identity and length of a particular web member 12 is verified. If the gathered data does not verify the identity of the measured web member 12, a signal can be emitted from the controller to indicate that the controller 31 could not identify the web member at the front of the conveyor and appropriate action may be taken. For example, if the board does not have the proper dimensions, an operator stops the system to manually inspect the board. If the operator confirms that the dimensions are incorrect, the operator may manually cut the board to the correct dimensions. In addition, the operator may need to inspect other boards to determine the system 200 is cutting and presenting the boards in the proper order. Further, it is contemplated that depending on the orientation and cut of the board, some web members may not have more than one leading edge, which is detectable by the sensors 107, 108. In such case, only the first leading edge on each side of the board will be measured and that data utilized to determine the identity and length of the particular web member.
In one embodiment, the web presenter 90, after verifying the identity of the web member, places the web member 12 on the assembly table 20 as indicated in FIG. 26 by grasping the web member at a center 216 of the length 212 between the confirmed two leading edges 204, 208 of the web member 12. In another embodiment, however, instead of placing the web member 12 on the assembly table 20 such that robotic arm 101 will pick up the web member at the center 216 of the web member 12, the controller 31 will cause the arm of the web presenter 90 to shift left or right to adjust the position of the web member 12 on the table 20 such that the robotic arm 101 will pick up the web member 12 at a staple center 218 of the web member. The staple center 218 may be defined as a length between a first staple location 220 and a second staple location 222 (where the web members 12 will be stapled to adjacent cord members 11A, 11B).
To illustrate an exemplary board, FIG. 34 shows the center 216 between the first leading edges 204, 208 of a web member 12, a center 224 between the second leading edges 206, 210 of the web member 12, and the staple center 218 between the first and second staple locations 220, 222. In the embodiment described above, the web presenter 90 will present the web member 12 on the assembly table 20 at a location such that the robotic arm 101 will pick up the web member 12 at the staple center 218.
To further illustrate the above apparatus, system 200, and method for verifying the identity of a particular web member 12 and adjusting the position of the web member on the assembly table, a particular example is provided. In this example, the distance between the two sensors is 130 inches, for example. When the web presenter 90 grasps the web member 12, the web presenter 90 is generally positioned to grasp the web member 12 using suction platen 202 or the like at an approximate center of the board, i.e., a centerpoint (65 inches) between the two sensors. However, in this example, the web member 12 is grasped by the web presenter on the conveyor 19B slightly off center at for example 1 inch to the left of a center 216 between the leading edges 204, 208 of the board. Thus, there are 64 inches to reach left sensor 107. In this example also, the web member 12, prior to verification, is believed by the controller 31 to be a web member having a total length of 40 inches.
First, the controller 31 causes the web presenter 90 to move leftward a distance of 46 (65-19) inches before the sensor detects a first leading edge 204 of the web member. Thereafter, the web presenter 90 will continue to move the web member 12 leftward until the second leading edge 206 is detected, which may be another couple of inches, for example. Thus, when the second leading edge 206 is detected, the web presenter 90 will have moved a total of 48 inches to the left. Thereafter, the controller 31 will generate a signal to cause the web presenter 90 to move to the right.
Since the web presenter 90 grasped the web member 12 slightly off center, the web presenter 90 will continue to move the web member 12 rightward until the right sensor 108 detects the first right leading edge 208 of the web member 12, which if the board is a 40 inch board, will be at 92 inches (65 inches-21 inches (half the board plus one inch off center) plus 48 inches. Thereafter, the web presenter 90 will further move the web member 12 rightward such that the second leading edge 210 is detected, which may be, for example, another six inches to the right. The controller 31 now has all the information necessary to confirm the identity of the web member 12. When the identity of the web member 12 is verified, the controller 31 can also identify the fact that the web presenter 90 has grasped the board one inch off-center to the left and account for the same.
Having the data stored therein, the web presenter 90 will now compensate for the staple center 218 of the web member 12. The location of the staple center 218 is predetermined and the information is stored with the controller 31. If for example, the staple center 218 is two inches from the center 216, the web presenter 90, after compensating for the one inch off-center noted above, will move the web member 12 to the left two inches when placing the web member 12 on the assembly table 20 as shown in FIG. 26 for pickup by the robotic arm 101.
Referring now to FIG. 36, the robotic arm 101 is shown as comprising a first lever arm 224 pivotally connected to a second lever arm 226. At an end of the second lever arm 226, there is mounted a movable clamping assembly and a stapling assembly mounted on a frame 234. The movable clamping assembly is shown as comprising two clamping devices 228 mounted on a frame 234. The stapling assembly is shown as including two staple guns 230 mounted on the frame 234. Of course, any number of clamping devices or stapling devices may be provided. One suitable source for a base model robotic arm 101 of the type described herein, which may be modified to include staple guns, clamping devices as is necessary, is the Fanuc Robot M-900iA-260L robotic arm.
Alternatively, instead of temporarily and/or permanently stapling two or more adjacent truss components together, such as cord members to cord members, web members to cord members, or web members to web members, the two or more truss components may be manually or automatically and temporarily and/or permanently secured to one another by applying an adhesive or taping the truss components together. If an automated adhesive dispenser or tape applicator is utilized, in one embodiment, the adhesive dispenser or tape applicator may be positioned at the same location on the robotic arm 101 as the staple guns 230 described above. Suitable adhesives, include, but are not limited to fast drying hot melt adhesives. If tape is used to secure two or more truss components together, the tape may be a double-sided foam tape available from 3M, for example. Alternatively, the adhesive or tape may be any other suitable adhesive or tape known in the art. Further, any suitable automated adhesive dispensing or tape application device known in the art may be utilized.
In one embodiment, the clamping devices 228 and staple guns 230 mounted on the second lever arm 226 are movable as a unit on a servomotor driven track 232, which is disposed on a base portion of the frame 234. The servomotor driven track 232 enables the lateral movement of the staple guns 230 and clamping devices 228 on the track 232 such that the clamping devices 228 can grasp a web member 12 from a position on the assembly table 20 adjacent the web presenter 90, place the web member 12 at its suitable position between cord members 11A, 11B, and the staple guns 230 can provide a staple to the truss 10 to at least temporarily secure a web member 12 to a cord member 11A, 11B. In one embodiment, the staple guns 230 are driven by contact such that when either of the staple guns 230 contact a web member 12 or cord member 11A, 11B, the staple gun or guns 230 automatically trigger to drive a staple into the web member 12 or cord member 11A, 11B.
In one embodiment, the clamping devices 228 include a first plate member 236 and a second plate member 238. The second plate member 238 is movable inward or outward relative to the first plate member 236 on a piston 240. In one embodiment, the second plate member 238 is movable inward or outward by way of a pneumatic cylinder 242 of the type set forth with respect to the pneumatic cylinder 186 above. The pneumatic cylinder may be of a double acting cylinder type, having two ports to allow air in, one for outstroke and one for instroke and the piston 240. The movement of the piston 240 allows the second plate member 238 to move inward or outward with respect to the first plate member 236 in response to any communication from the controller 31 that there is a web member 12 for the clamping device 228 to grab or release.
Once the web member 12 on the assembly table 20, the robotic arm 101 will pick up the web member 12 at the staple center 218 and will position the web member 12 for attachment to corresponding cord members. As shown in FIG. 35, for example, the robotic arm 101 is shown placing a web member 12 in position for attachment to the cord members 11A, 11B. As illustrated, the bottom right corner of cord members 11A, 11B has already been advanced on the table 20 to a position where the press 71B will move into position to stamp connector plates 72 at the corner as described above. In addition, the cord members 11A, 11B are positioned on the table 20 to receive the first web member 12 at location on the table 20 between the roller guides 42A, 42B.
The robotic arm 101 may be programmed to distinguish web members 12 from one another. The robotic arm 101 is programmed to retrieve each web member 12 at a particular location having an x,y,z coordinates relative to the end of the robotic am 101 and ground. In one embodiment, the web presenter 90 positions the staple center 218 of each web member 12 at that location. Similarly, the robotic arm 101 is programmed to position the staple center 218 of the web member at the above-mentioned predetermined positions which have x,y,z coordinates relative to the end of the robotic arm 101 and the ground. The controller 30 and components of the assembly table (clamping devices, roller guides etc.) are programmed to advance the truss 10 on table 20 to a position so the web member 12 fits between and abuts the inside edges of the cord members 11A, 11B.
When the robotic arm 101 has retrieved the web member 12 as described above, the controller 30 or 104 generates one or more signals responsive to which the robotic arm 101 moves on a gantry 120 and/or rotates to grab the web member 12. The robotic am 101 then places the staple center 218 (not shown here) of web member 12 at a first predetermined location that so the ends of the web member 12 are displaced to the left of the cord members 11A, 11B. The robotic arm 101 then moves the center 218 of the web member 12 to the right so that each end of the web member 12 abuts an inside edge of a respective cord member 11A, 11B as shown in FIG. 35.
The controller 30 or 104 is in electrical communication with a processor of the robotic arm 101, to determine when the web member 12 is appropriately positioned for attachment to the cord members 11A, 11B. At that time, the controller 30 or 104 generates one or more signals, responsive to which staple guns 230A, 230B move across the table 20 to staple the web member 12 to the cord members 11A, 11B. The controller 30 or 104 monitors the movement of a servo-driver (not shown) connected to the staple gun 230A or 230B so the controller 30 is able to determine when the staple guns 230A, 230B (and the presses 71A, 71B described above) return to a home position, so the truss 10 may be advanced on the table 20.
Typically, the truss 10 is thereafter advanced on the table 20 a sufficient distance so the points at which the web member 12 abut the inside edges of the cord members 11A, 11B, are aligned with the presses 71A, 71B. In this manner, the presses 71A, 71B, responsive to one or more signals from the main controller 30, move on I-beam 144 to press connector plates 72 onto the truss, thereby securing the web member 12 to the cord members 11A, 11B as described previously herein. As the presses 71A, 71B are moving and/or stamping the connector plates 72 on the truss 10, the robotic arm 101 is retrieving a second web member 12 and placing it in position relative to the cord members 11A, 11B for assembly of the truss 10. These steps are repeated for all the web members 12 for a particular truss until the truss 10 is fully assembled.
As shown in FIG. 2, the assembled truss 10 may also be advanced on the assembly table 20 a sufficient distance by rollers 36 to a main press 39 where larger connected plates may be pressed on portions of the truss as needed. As shown in FIG. 37, main press 39 includes an upper platen 244 and a lower platen 246 that are supported on opposed beams 248 supported by a large frame 250. The beams 248 are capable of being raised or lowered toward one another by a hydraulic cylinder as is known in the art, thereby allowing the upper platen 244 and the lower platen 246 to move toward one another with sufficient force to press a relatively large connector plate (not shown) on the truss components.
In addition, the main press 39 may include one or more pneumatic cylinders, including one of the type described with respect to presses 71A, 71B to separate any two connector plates 72 when the two connector plates are placed on a lower platen 246. Further, the pneumatic cylinder may aid in retracting the platens 244, 246 after the connector plates 72 are pressed onto a particular truss 10. In one embodiment, the pneumatic cylinder is embedded in the upper platen 244 and the upper platen includes a magnet (not shown) to aid separating any two connector plates that are placed on the lower platen 246.
In one embodiment, the clearance space 252 between the upper platen 244 and the lower platen 246 when the press 39 is in an idle position is relatively small, i.e., about three inches. In this way, when the platens 244, 246 are moved toward one another to press a large connector plate on a portion of the truss 10, the truss and/or connector plate is not bent, crushed, twisted, or otherwise damaged.
The present invention, in various embodiments, includes components, methods, processes, systems and/or apparatus substantially as depicted and described herein, including various embodiments, subcombinations, and subsets thereof. Those of skill in the art will understand how to make and use the present invention after understanding the present disclosure. The present invention, in various embodiments, includes providing devices and processes in the absence of items not depicted and/or described herein or in various embodiments hereof, including in the absence of such items as may have been used in previous devices or processes, e.g., for improving performance, achieving ease and/or reducing cost of implementation.
The foregoing discussion of the invention has been presented for purposes of illustration and description. The foregoing is not intended to limit the invention to the form or forms disclosed herein. In the foregoing Detailed Description for example, various features of the invention are grouped together in one or more embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate preferred embodiment of the invention.
Moreover, though the description of the invention has included description of one or more embodiments and certain variations and modifications, other variations and modifications are within the scope of the invention, e.g., as may be within the skill and knowledge of those in the art, after understanding the present disclosure. It is intended to obtain rights which include alternative embodiments to the extent permitted, including alternate, interchangeable and/or equivalent structures, functions, ranges or steps to those claimed, whether or not such alternate, interchangeable and/or equivalent structures, functions, ranges or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter.

Claims

1. A system for the automated assembly of a truss, comprising:

a first station having one or more automated saw systems for cutting lumber into truss components, including a plurality cord members and web members, wherein the automated saw systems comprise a controller programmed with a specification to cut the cord members and web members in a predetermined order representative of an order in which the components are assemble relative to one another;

a second station, in conveyor communication with the first station, wherein the cord members are supported and positioned relative to one another form a perimeter of the truss, and wherein the second station comprises a controller that is programmed to position the cord members relative to one another in accordance with the specification;

a third station, in conveyor communication with the first station, that supports the cut web members which are positioned relative to one another in a predetermined order of attachment to the cord members and in accordance with the specification;

means, at the second station or third station and responsive to a controller, for engaging a web member at the third station and transferring the web member to the second station and positioning the web member relative to the cord members for attachment; and,

means, at the second station and responsive to a controller, for securing two or more truss components in accordance with the specification.

2. The system of claim 1, wherein the second station further comprises an assembly table and a plurality of grasping members for grasping cord members and for orienting the cord members relative to one another on the assembly table, and wherein the grasping members are laterally movable on the assembly table for orienting a cord member at an angle relative to an adjacent cord member.

3. The system of claim 2, wherein the grasping members comprise a register for engaging an inner portion of the cord member and a plurality of rollers for engaging an outer portion of a cord member.

4. The system of claim 2, wherein the second station further comprises a plurality of passive rollers for conveying cord members in a downstream direction along the assembly table.

5. The system of claim 2, wherein the grasping members further comprise a pivot arm, wherein the pivot arm is movable from a first position where the register and plurality of rollers engage a cord member to a second position where the register and plurality of rollers do not engage the cord member.

6. The system of claim 1, wherein the third station comprises:

a robotic arm for grasping a cut web member conveyed to the third station; and

means for verifying the dimensions of the cut web member; and

a controller for comparing first stored values for the dimensions of the cut web member with second values obtained from the means for verifying.

7. The system of claim 1, wherein the means for securing comprises a robotic arm mounted for lateral movement over a portion of an assembly table of the second station or third station, wherein the robotic arm comprises one or more staple guns and one or more clamping members for orienting and securing two or more truss components.

8. The system of claim 1, wherein the means for securing comprises means for applying adhesive to a junction of two or more truss components.

9. The system of claim 1, further comprising means for affixing a connector plate to the two or more truss components, wherein the means for affixing a connector plate comprises:

a plurality of bins for storing a plurality of connector plates;

a robotic arm for grasping two or more connector plates from one of the plurality of bins;

a press for affixing the two or more connector plates comprising upper and lower magnetized platens mounted for up and down movement relative to one another, wherein the press is mounted for lateral movement over an assembly table of the second or third station for affixing the two or more connector plates at a junction of the two or more truss components.

10. The system of claim 1, wherein the bin assembly comprises:

a base;

a plurality of bins mounted on the base, wherein the plurality of bins comprise a tray and a connector plate storage compartment for storing a plurality of connector plates; and

means, within a bin, for dispensing two or more connector plates from the connector plate storage compartment to a front portion of the tray.

11. The system of claim 10, wherein the means for dispensing two or more connector plates comprises:

an engagement member mounted for lateral movement on the tray; and

an actuating mechanism for causing movement of the engagement member toward the connector plate storage compartment when activated.