US20060293622A1

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Info

Publication number: US20060293622A1
Application number: US11/401,084
Authority: US
Inventors: Wesley Scott; Marcus DeLaMerced
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-10-10
Filing date: 2006-04-10
Publication date: 2006-12-28
Also published as: US7582847B2; US20050106526A1; CA2470029A1

Abstract

A system and method for producing braces for a cavity die having a predetermined shape are disclosed. The system includes an input file containing information about the shape of the cavity die and a bracing program running on a computer. The bracing program produces an output file based on the input file and brace parameters. The output file includes information about the design of the braces. The computer instructs a brace-making machine to produce the braces based on the information in the output file. The method includes the steps of: a) providing input information about the shape of the cavity die and the brace parameters to the computer; b) processing the input information by the computer to produce an output file containing information about the design of the braces; and c) producing the braces in accordance with the information from the output file.

Description

This is a continuation of International Application No. PCT/CA2004/001809 filed Oct. 8, 2004 and a continuation of U.S. application Ser. No. 10/959,985 filed Oct. 8, 2004 which is an application claiming the benefit under 35 USC 119(e) to U.S. Provisional Patent Application Ser. Nos. 60/509,867 and 60/509,868, both filed Oct. 10, 2003. All of the applications listed above are incorporated herein, in their entirety, by this reference to them.

FIELD OF THE INVENTION

This invention relates to a system and method for producing braces for a cavity die. The invention may also have application in other fields in which a strip material must be cut to fit to a boundary.

BACKGROUND OF THE INVENTION

U.S. Pat. No. 6,233,809 describes a cutting knife that can be detachably connected to a baseboard. The cutting knife extends in a perpendicular direction to the baseboard and circumscribes the knife cavity on the baseboard. At least one elongated cross member is affixed to the cutting knife and extends across the knife cavity. The cross member is mounted to the baseboard by a removable fastener. The cutting knife may then be removed from the baseboard and re-secured. The cutting knife described in the '309 Patent does not provide any means for designing and producing braces for cutting knives of various shapes. U.S. Pat. No. 6,233,809 is incorporated herein, in its entirety, by this reference to it.

Accordingly, there is a need for systems and methods for more easily designing and producing braces for dies.

SUMMARY OF THE INVENTION

It is an object of the invention to improve on, or provide a useful alternative to, the prior art. It is also an object of the invention to provide systems or methods for designing or producing braces for dies or designing or cutting a strip material to fit a boundary. The following summary is intended to introduce the reader to the invention by not to define the invention. The invention may reside in a combination or sub-combination of elements or steps found in this or other parts of this document, for example in the claims.

According to a first aspect of the invention, a system for producing a brace for a cavity die having a predetermined shape is provided. The system comprises: a) an input file containing information about the predetermined shape of the cavity die; b) a data processor configured by a bracing program to produce an output file from the input file and a plurality of brace parameters, wherein the output file comprises information about the design of the brace; and c) a brace-making machine adapted to produce the brace, the brace-making machine adapted for communication with the data processor; wherein the data processor is adapted to instruct the brace-making machine to produce the brace from the information in the output file.

According to a second aspect of the invention, an apparatus for producing a brace for a cavity die from a strip of material is provided. The apparatus comprises: a) a bed for supporting the strip of material; b) a material feeder for moving the strip of material in a first direction; c) a cutting tool movable in a second direction across the strip of material; and d) a control system for coordinating the movement of the material feeder and cutting tool to make a desired cut in the strip of material.

According to a third aspect of the invention, a method of producing a brace for a cavity die having a predetermined shape is provided. The method comprises: a) providing input information to a data processor, the input information comprising information about the predetermined shape of the cavity die and brace parameters; b) processing the input information by the data processor to produce an output file containing information about the design of the brace; and c) producing the brace in accordance with the information from the output file.

According to a fourth aspect of the invention, a method of producing an output file containing information for the design of braces for a cavity die having a predetermined shape is provided. The method comprises: a) providing input information to a data processor, the input information comprising information about the predetermined shape of the cavity die and brace parameters, the brace parameters comprising brace width, starting brace centre point from edge, minimum brace spacing and maximum brace spacing; and b) processing the input file and the brace parameters to produce the output file, wherein the processing step comprises:

i) drawing a pair of edge braces having parallel centerlines and located at the starting brace center point from edge distance from the furthest points of the cavity die perpendicular to the centerline of the edge braces, the edge braces having a constant width equal to the brace width and end profiles determined by intersection with the shape of the cavity die; and

ii) if the distance between the edge braces is greater than the maximum brace spacing, drawing a number of interior braces having centerlines parallel to the edge braces and regularly spaced between the edge braces, the number being the lowest number such that the regular spacing is between the minimum brace spacing and maximum brace spacing, the interior braces having a constant width equal to the brace width and end profiles determined by intersection with the shape of the cavity die.

According to a fifth aspect of the invention, a computer readable medium having a computer program recorded thereon for producing an output file containing information for the design of braces for a cavity die having a predetermined shape is provided. The computer program causes the computer to perform the steps of: a) accessing information about the predetermined shape of the cavity die; b) accessing brace parameters relating to the location of the braces, the brace parameters comprising brace width, starting brace centre point from edge, minimum brace spacing and maximum brace spacing; and c) processing the input file and the brace parameters to produce the output file, the processing step comprising:

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments of the invention will now be described, by way of example, with reference to the following figures:

FIG. 1 is an isometric view of a braced cutting die.

FIGS. 2A through 2F are plan views of a selection of dies of various shapes.

FIG. 3 is a schematic representation of a brace making system.

FIG. 4 is a flow chart of steps followed to determine the shape and location of braces.

FIG. 5 is a flow chart of the sub-steps withinstep48 ofFIG. 4.

FIG. 6 is a front elevation view of a brace-making machine.

FIG. 7 is a back elevation view of the brace-making machine.

FIG. 8 is a partial plan view of the brace-making machine.

FIG. 9 is a schematic representation of an end clamp of the brace-making machine.

FIG. 10 is a schematic representation of a piston unit of the brace-making machine.

FIG. 11 is a schematic representation of a guide mechanism of the brace-making machine.

FIGS. 12, 13, and14 are schematic representations of a computer control system for the brace-making machine.

FIG. 15 is a flow chart of method of producing a brace.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 is an isometric view of a cutting die10. Cutting die10 has aknife12 constructed from a strip of material having acutting edge14 on one of its sides. Theknife12 is bent at various angles to provide a closed predetermined shape or cavity defined by the point of thecutting edge14. Theknife12 is typically made from steel. Thecutting edge14 may have various types of bevel such that the point of thecutting edge14 may be in the centre of the thickness of theknife12, offset to one side, or at one edge of theknife12. Depending on the application, theknife12 may have perforations in its sides, gates cut out of the cutting-edge14, or notches cut out of the non-cutting edge.

The die10 also hasbraces16 which serve a number of purposes. Depending on the application, these purposes may include one or more of: (i) supporting theknife12 or helping to maintain the shape of the die; (ii) distributing the forces from thedie10 to a base board (not shown), (iii) providing a means for mounting dies to a base board, and (iv) providing a means for mounting other items, such as cut-outs, punches, stabs or slit knives, to the die10.

Continuing to refer toFIG. 1, thebraces16 are typically located within the area bounded by theknife12 to avoid interfering with any adjacent dies mounted to the same base board. Thebraces16 are typically made of steel and welded at their ends toother braces16 or to theknife12. The braces may be cut from a strip of material (also known as “strip stock”), their ends being cut to match the inner surface ofknife12, or any other surface to which they are attached, to within the tolerances required by welding or any other method of attachment used. In the case of a die10 intended to be mounted flush with the surface of a baseboard, as for the die10 shown, thebraces16 are mounted flush with non-cutting edge of theknife12 and includeholes18 for inserting a fastener, such as a screw, to attach the die10 to a baseboard. For other sorts of dies, the braces may be located in different locations. For example, for dies in which theknives12 will be embedded into a baseboard, thebraces16 may be located at a point between the two edges of the knife so as to contact or remain above the baseboard when theknife12 is pounded into the baseboard. Theknife12 may also havenicks20, also called marker notches, which are used, for example, to provide alignment or folding tabs in the material to be cut by thedie10. Thenicks20 may extend only partially into theknife12 as shown or may extend to the non-cutting edge of theknife12. If thenicks20 extend through the plane of thebraces16, thebraces16 may be cut to the contour of thenicks20 or the location of thebraces16 may be adjusted to avoid thenicks20.

FIGS. 2A to2F show plan views of a selection of dies10 of various shapes. As shown in the figures, the braces can have a variety of configurations and locations. For example, die10ainFIG. 2A includesbraces16aextending between interior surfaces of theknife12a. Thebraces16a′ shown closest to the left or right side of the die10amay be called edge braces. Theother brace16a″ may be called an interior brace.Braces16p, which may be called supports, may be attached, for example by welding, between the other braces16.Other braces16b, which may be called tabs, may be attached, for example by welding, between the interior surface of theknife12aand abrace16a. Die10binFIG. 2B includes a set ofbraces16cextending parallel to each other and

additional braces

16dand16ethat are not parallel tobraces16c. Die10cinFIG. 2C includes a set ofbraces16fsupporting theknife12cand anadditional brace16g, which may be called a cross-brace, supporting apunch22. Aside from thepunch22, the cross-brace16gmight support other items, such as cutouts, stabs or slit knives, in position relative to theknife12. Thepunch22 or other items may be attached to abrace16 by various means including welding, fasteners, such as screws or clips, or a press fit into a hole in thebrace16. Multiple braces16 may be used to support large punches or other items. The cross-braces16gmay be separate braces provided only to provide a punch or other item or may bebraces16 provided for other purposes that additionally perform the function of a cross-brace16g.

The dies10 and braces16 described in FIGS.2A-C are typical of the majority of dies10. However, dies10 of unusual shapes occur from time to time and may be braced to account for their unusual shape. For example, die10dinFIG. 2D has a set ofbraces16hparallel to one direction and a second set ofbraces16iparallel to another direction. The two directions each correspond to the shape of a part of the die10d. The two directions are generally perpendicular to each other in the die10dalthough other dies may have directions at other angles to each other. The die10eofFIG. 2E has a set ofbraces16j′ spaced at multiples of a constant spacing interval and abrace16j″ spaced at a different spacing. The location ofbrace16j″ is adjusted to support theinterior corner22 of theknife12fbut without requiring a cut in the side ofbrace16j″.Brace16kmay also be added to reinforce the peninsula indie10e.Die10finFIG. 2F has braces16mand16l, which may all be called edge braces, forming a closed shape, such as a rectangle, inside of theknife12g. Braces ortabs16nextend from brace16lto theknife12g. Brace16lalso extends to theknife12gbut may optionally extend only to the outside edge ofbrace16m. In that case, tabs may be added to replace the lost extensions of brace16land provide connection with theknife12geither in the same location as the lost extensions of braces16lor in other locations. Additional tabs16omay be added. The bracing scheme used inFIG. 2F can be generally described as having a set ofbraces16 forming a closed shape within the die10fand having a set oftabs16n,16oand the extensions of16l, extending to theknife12g.

Dies10 of shapes other than those shown inFIGS. 2A through 2F may also occur in practice and braces16 as described in one or more of these figures may be selected, combined or adapted to provide bracing.

FIG. 3 shows asystem30 for making braces in accordance with a preferred embodiment of the present invention. The system includes any suitable data processor, such as acomputer31 which executes instructions from a bracing program32 (described in detail below) loaded thereon. Input devices, such as akeyboard34aand drive34b, or other input devices, allow for the input of aninput file33, and optionally brace parameters, to thecomputer31. Anoutput file35 with information, for example regarding the shape of one or more braces to be cut, may be communicated from thecomputer31, optionally via anysuitable communications network36, to a brace-making machine38 (also referred to as the apparatus) described in detail below. The brace-makingmachine38 receives the output file, reads the output file to determine the shape of one ormore braces16 to be cut, and cuts the one or more braces16. Alternately, the output file from thecomputer31 may be output, optionally through thecommunications network36, to a printer orplotter39. The printer orplotter39 reads the output file and produces a drawing showing the shape of one ormore braces16 to be cut. The printer orplotter39 may also produce a drawing showing braces16 in position in a die10 to be braced to aid in later assembly of thedie10.

The operation of thecomputer31 running the bracingprogram32 will now be described with reference toFIGS. 1, 3, and particularlyFIG. 4.

The operation begins atstep40, where theinput file33 is loaded into the bracingprogram32. Theinput file33 includes information about the shape of the die10 to be braced. To load theinput file33, a user may, for example, browse through and select a file from one or more folders of available files ondrive34b, or otherwise specify a file to be loaded. Theinput file33 may correspond to an article of manufacture or production run and may contain information on the shape of a number of different dies.

The bracingprogram32 is adapted to read theinput file33 in one or more forms and according to one more protocols. For example, the input file may be a Data Exchange File (DXF) file created in a separate drafting program, such as AutoCAD™ as supplied by Autodesk Inc., which contains information about the shape of the die. The die shape is made up of several line segments, for example segments corresponding with the shape enclosed by the point of thecutting edge14.

The protocol may include rules for preparing or formatting the information within the DXF file. For example, the bracing program may require that all data relating to the shape of a die10 be tagged with a group code number distinct from the group code number of any other information in the file. This allows the bracing program to identify and separate information relating to the shape of a die10 to be braced from information relating to other dies10 or title blocks, notes, or other information in a file. In files prepared in AutoCAD™, this is achieved by placing the information relating to the shape of the die in a distinct BLOCK enclosed by BLOCK . . . ENDBLK. Multiple dies can be included in an input file as long as each is included in its own block and the ENTITIES section is set to display all shapes if required to allow an operator to choose the die10 of interest. The protocol also includes rules regarding the scale and units to be used, for example, that the scale will be 1:1 and all units will be inches. The protocol may also include rules prohibiting any type of shape description not understood by the bracing program, which may include, for example, ARC or POLYLINE functions in AutoCAD. Alternately, the bracingprogram32 may be modified to avoid the need to address some or all of these issues in the protocol. For example, the bracingprogram32 may be modified to read ARC or POLYLINE functions and convert them to a series of line segments.

Other rules may also be included in the protocol to aid the bracingprogram32 in performing various functions. For example, rules may relate to the organization of information about adie10 within layers of a block. For example, the basic shape of the die10, or the point of itscutting edge14, may be included on one layer while information on the location of punches or other internal features of a die may be placed on separate layers. This allows the bracingprogram32 to locate information required for certain steps and separate the required information from other information contained in the complete file for thedie10. Alternately, the bracingprogram32 may be modified to solve or bypass issues addressed in the protocol so that the protocol may be simplified. For example, the bracingprogram32 may be modified to include routines which scan theinput file33 and identify perimeters of dies and features inside the perimeter of a located die such that information does not need to be provided in blocks or layers as described above.

Instep42, theinput file33 is converted if required. Althoughstep42 is shown as part of the bracingprogram32, a separate program may also be used to perform the conversion either before a file is input to the bracingprogram32 or upon receiving a file exported from the bracing program.Step42 may also be embodied in one or more routines of the bracingprogram32 which run automatically, optionally without input from a user or reporting to a user. Further, step42 may be broken into various component steps or conversions performed by one or more separate programs or sub-routines of the bracingprogram32 at other suitable locations within the overall process or at dispersed locations within the overall process.

Step

42 may include operations to bring an input file into compliance with the protocol. For example, step42 may include moving information in an input file between blocks so that all information regarding the shape of a die10 is located in a distinct block for each die10. Un-supported shape information, such as a POLYLINE, may be converted to a series of line segments.

Step

42 may also include operations to facilitate the work of the bracingprogram32 in place of expanding the protocol or requiring other operations later in the overall process. For example,nicks20 may be included in the shape of a die10 but not pass through the plane of thebraces16. Accordingly, thebraces16 do not need to be cut to clear thenicks20. Rather than requiring in the protocol that the input file be prepared with the nicks deleted,step32 may include a conversion routine that scans the input file fornicks20 and replaces them with a line segment. To locatenicks20, the nick removing routine searches for shapes within or similar to a specification, which may be input by the user or contained in pre-existing configuration file, for the shape of anick20. The conversion routine or program may also account for input files that contain shape information relating to the point of thecutting edge14, as is typical. Since the point of thecutting edge14 may be offset from the side of theknife12 that will contact abrace16, this offset must be accounted for. A similar offset occurs where there are punches or other items to be supported bybraces16 within adie10. Offset relating to these internal items may be accounted for instep42, for example, by increasing the size of such internal features as required by the offset. Optionally, some functions instep42 may be performed after the shapes of the braces are determined. For example, the offset between the side of theperimeter knife12 and the point of thecutting edge14 may be accounted for by adjusting the shapes of the braces after they are determined.

Instep44, a die10 to be braced is selected from the input file. An individual die10 can be selected, for example, by browsing through a display of all dies10 and selecting the desireddie10, by selecting from a list of alpha-numerical designations corresponding to the dies10, or by otherwise indicating the BLOCK number for the desireddie10. The selected die10 may then be displayed on a screen and the user may be asked to confirm the selection or make another selection. Once anindividual die10 has been selected for bracing, an initialization routine clears any previous shape information and may clear or reset appropriate parameters to default values. The block representing the selected die is copied from the input file for more convenient access by other routines of the bracing program. The name or designation for the die10 may also be copied into a file location within the bracing program.

Instep46, parameters relevant to the number and location ofbraces16 are input. These bracing parameters may be input by the user through thekeyboard34ain response to prompts after thedie10 is selected.Step46 may also be performed by other means, for example by inputting a parameter file or including the parameters in the general input file for extraction by the bracingprogram32.Step46 may also be performed at other times in the process, for example, before the input file is loaded. The bracing parameters may be based on pre-established guidelines designed to ensure that the bracing will be appropriate and sufficient for the intended use of thedie10. Sets of bracing parameters may be pre-determined for use for various classes or types of dies10. The classes or types of dies10 may be determined depending on die10 geometry, whether there are punches or other internal features and where they are located, mounting requirements for the die10, the materials used in thedie10, the type of press that the die10 will be used with or other factors. Thus, the parameters may embody the engineering required to produce an acceptable system ofbraces16 for dies10 of different shapes to be used in similar applications. Alternatively, for example where most or all dies10 to be braced will have similar requirements, a single set of bracing parameters may be determined and embodied in the bracing program such thatstep46 becomes a part of the working of the bracing program hidden from the user. Further alternatively, the bracing program may be adapted to review thedie10 and determine appropriate bracing parameters itself either by computation or by selection from a set of previously entered or programmed bracing parameters.

The set of bracing parameters is chosen in view of the needs of the method that will be used to determine the shape and location of the braces. For the method to be described below, bracing parameters are as described below.



Bracing Parameter	Description

Brace Width	the width of the material that the braces will be
	cut from
Starting Brace	the perpendicular distance to the edge of the die
Center Point	of the centerline of the edge braces
from Edge
The Edge Bracing	the maximum length of the outer edge of an
Extra Support	edge brace permitted when the edge brace is
Length	located at the Starting Brace Center Point from
	Edge distance
Start Brace Center	the perpendicular distance from the centerline of
from Edge if Over	an edge brace to the edge of the die to be used
Support parameter	if the Edge Bracing Extra Support Length is
	exceeded
Minimum Brace	the minimum spacing between the centerlines of
Spacing	adjacent edge or interior braces
Maximum Brace	the maximum spacing between the centerlines of
Spacing	adjacent edge or interior braces
Internal Bracing	a length for internal edges of braces which, if
Support Length	exceed, indicates that extra support bracing is
	required
Brace Mounting	the diameter of the mounting holes for the
Hole Diameter	braces as modified, if appropriate, for any offsets
	of a computer controlled device that will cut the
	holes
Brace Mounting	the distance from the edge of a brace used to
Distance from Edge	determine the center points of any mounting
	holes

Other parameters may also be required by the bracingprogram32, and can be input at the same time asstep46 or at other appropriate times. For example, parameters representing the offset of the point of thecutting edge14 to the side of theknife12 may be entered directly or by specifying the type of material used for theknife12 and having the program reference a table of offsets for different materials. Parameters representing the offset of the cutting point and side of a punch or other internal feature of the die may also be entered in a similar manner. Parameters representing the shape ofnicks20 may be entered ifnicks20 are to be identified and removed by the bracing program. Nick parameters may include the minimum length of one of the lines forming thenick20, the maximum length of thenick20 along the die perimeter, the minimum included angle of thenick20 or the minimum angle formed between a first side of thenick20 and anadjacent die10 segment. Other parameters may also be useful for additional features in other steps. For example, if the bracingprogram32 is capable of detecting and correcting discontinuities in the shape thedie10, a radius may be specified for searching for adjacent un-joined line segments. Another parameter may indicate whether holes are required or not. The various parameters may be entered all at one time or the parameters may be input at multiple times dispersed throughout the overall process.

Instep48, the number and location of braces is determined.Step48 can be broken into various sub-steps shown inFIG. 5.

Referring now toFIGS. 1, 3, and5, thedie10 is checked for any discontinuities in its perimeter atstep50. If any discontinuities are detected, a subroutine may be invoked to search for adjacent un-joined line segments within a specified radius and propose a method of joining the segments. If no adjacent un-joined segment is found, or if the proposed joinder produces unacceptable results as shown on a screen, the operator may terminate the program. Possible discontinuities may also be dealt with as part ofstep42 or by requiring continuous shapes in the input file protocol.

Instep52, thedie10 is oriented to a reference direction. In the following description, the reference direction is assumed to be horizontal, although other reference directions may be used with appropriate modification. To orient thedie10, a rectangular outline of the die10 is drawn having horizontal and vertical sides touching the outer edges of thedie10. Thedie10 is fully contained within the rectangle but the rectangle is no larger than required to fully contain thedie10. Thedie10 is then rotated in increments through a specified range of rotation. At each angle, a new rectangle is drawn and the area of the new rectangle is determined and stored. After thedie10 has been rotated through the specified range of rotation, the areas of the rectangles at each rotation are compared and the die is returned to the rotation that produced the rectangle of the smallest area. This step may be performed fully automatically where, by drafting convention or the input protocol, the dies10 tend to be oriented generally horizontally in the input file or the range of rotation is large enough to account for randomly oriented dies10. In an operator assisted variation, the operator may initially rotate the die10 to a position that appears would give the smallest rectangle or in which the features of shape of the die10 are primarily either vertical or horizontal.Step52 may then be performed as described above through a more limited range of rotation. Once the smallest rectangle has been found, thedie10 is rotated again, if necessary, so that the longest side of the rectangle of minimum area is horizontal.

Instep54, the location and shape of the edge braces16 are determined. This is done by first drawing two edge braces16 of the specified Brace Width. The centerlines of the edge braces16 are vertical and spaced at the Starting Brace Center Point from Edge distance from the furthest left and right points on thedie10. The shape of the ends of the edge braces16 is determined by intersection with the perimeter of thedie10. The length of the outside edge of each edge braces16 is then determined. If either edge brace has an outside edge longer than the Edge Bracing Extra Support Length, then that edge brace is relocated so that its centerline is at the Start Brace Center from Edge if Over Support distance from the furthest left or right, as appropriate, edge of thedie10. The Start Brace Center from Edge if Over Support distance is larger than the Starting Brace Center Point from Edge distance since tab braces16 may be added as described in step58 (described below).

Instep56, the number, shape and location ofinterior braces16 is determined. To do this, the horizontal distance between the centerlines of the edge braces16 is determined. This horizontal distance is divided into a number of equal parts that produces the lowest number ofinternal braces16 spaced between the Minimum Brace Spacing and Maximum Brace Spacing. Internal braces16 are drawn with their centerlines vertical and passing through points dividing the horizontal distance into a number of equal parts. End shapes of theinternal braces16 are determined by intersection with the perimeter of thedie10.

Instep58, the number shape and location of any tab braces16 is determined. To do this, the length of the outer edge of anyedge brace16 located at the Start Brace Center from Edge if Over Support distance is determined. If this length is greater than the Edge Bracing Extra Support Length, tab braces16 will be provided. If so, the length is divided by the Edge Bracing Extra Support Length and the resulting number is truncated to a whole number representing the number of tab braces16 required. The location of these tab braces16 along the edge braces16 is then determined by dividing the length of the exterior edge of theedge brace16 by the whole number plus one. Tab braces16 are located with their centerlines horizontal and passing through the division points. One end of eachtab16 is cut square, the other is shaped by intersection with the perimeter of thedie10.

Instep60, the number, shape and location of any support braces16 are determined. To do this, each pair of adjacentvertical braces16 is considered. Internal braces16 will be considered as part of two pairs while edge braces16 are only considered as part of one pair. For each pair ofbraces16, the length of the right edge of theleft brace16 and the left edge of theright brace16 is determined. If either edge is longer than the Internal Bracing Support Length, then supports16 will be added. To locate the support braces16, the longer edge is divided by the Internal Bracing Support Length and the resulting number is truncated to a whole number representing the number of support braces16 required for that pair ofvertical braces16. The longer edge is then divided by the whole number plus one and support braces16 are added with their centerlines horizontal and passing through the points of division. The ends of eachsupport brace16 has a squared off shape. Alternate routines for providing support braces may also be used. For example, the program may first provide supports to the right edge of theleft brace16 of a pair and then check the left edge of the right brace of the pair to determine if it still has a need for more support braces16.

Instep62, the number, location and shape of any cross-braces is determined. To do this, the layer in theinput file33 which may contain information about punches or other internal elements according to the protocol is checked to determine whether there are any such elements. The maximum dimension of any internal feature, plus any offset if appropriate, is compared to the Brace Width. For internal features smaller than the Brace Width, across brace16 is added with its centerline oriented along the shortest vertical or horizontal line to anyother brace16. For larger internal features, two or more braces are drawn side by side to provide the required width. For very large internal features, the user may modify the cross-bracing determined by the program as appropriate.

Instep64, mountingholes18, if any, are automatically placed at the end of abrace16 that intersects with the die10 perimeter. Whether there are to be any holes depends on the intended use of the die10 as communicated to the program by an input parameter. The bracingprogram32 calculates the placement of the mountingholes18 in the following manner: (i) the longitudinal centerline of the brace is found to divide thebrace16 into two half widths; (ii) for each brace half-width, a line perpendicular to the brace centerline through the most interior point where the half-width intersects the die perimeter is found; and (iii) mountingholes18 are placed at the Brace Mounting Distance horizontally inward from thebrace16 edge vertically inward from the line described above. The mounting holes18 are made to have the Brace Mounting Hole Diameter. Mountingholes18 are also placed at the center of abrace16 if the brace length is greater than 10″. If the brace length is less than 1.5″ and both ends intersect with the die perimeter, two mountingholes18 are placed in the centre of thebrace16. When automatic brace placement is complete, the braces are numbered or otherwise identified.

Instep66, the bracing may be modified by the user by moving, adding or deleting braces16. For this purpose, the bracing scenario is shown to the user on screen of thecomputer31. The user may then add, move or delete abrace16 by any convenient input devices. Once relocated or added, braces16 are re-numbered and there may be an automatic or manual adjustment ofother braces16, i.e. internal braces. Before permitting abrace16 to be added or moved, the bracingprogram32 may check for compliance with location rules, such as the following rules: (i) that thebrace16 must lie within thedie10, (ii) thebrace16 cannot be located within apre-existing brace16, (iii) the end of abrace16 may not intersect both anotherbrace16 and the die10 exterior, and (iv) anangled brace16 can not overlapother braces16, and vice versa. A request to add a horizontal orvertical brace16 across anotherbrace16 may be interpreted as a request formultiple braces16 in line.Braces16 may be added, moved or deleted to achieve the results as described inFIGS. 2B, 2D,2E or2F. While these modifications may be performed by the user in the embodiment described, the program may alternately be modified to achieve similar results.

One example of a special case is a die, such as an L-shaped die, that does not fit the rectangular model used in the method. Such dies may be instead separated into two rectangular regions with braces in each region parallel to the smallest dimension of that region. The bracingprogram32 may be modified to locate L-shaped dies by comparing the lengths ofsuccessive braces16 and, if an increase in length beyond a parameter is found, rotating the reference direction for an area above the last brace (before the large increase in brace length) and re-drawing the braces for that area. Dies that have long interior protrusions or corners need support at those corners. Braces on these dies need to be positioned such that the interior corner is supported. In these cases, the braces are positioned according to the method above, but then one of the interior braces is moved until it supports the corner without a cutout in the brace, provided that the movement still meets the minimum and maximum spacing rules. This can also be achieved in the bracingprogram32 by searching for these features and then moving the closest brace towards the feature in small steps until the corner is supported. Then, the perimeter of the die is checked to determine if the unsupported length of any section ofknife12 has increased such that an additional brace is required. Large rectangular or square dies having a smallest dimension of greater than 8 inches may be braced on all four sides with perpendicular tabs linking the bases to the outside of the die. The perpendicular tabs should be spaced according to the above method.

Referring again toFIGS. 1, 3 and4, the shape, quantity and location ofbraces16 for a givendie10 are provided as an output instep49. The output may take any convenient form. For example, the output may be theoutput file35 produced in a form suitable for further processing, such as by the brace-makingmachine38. Alternately, the bracing scenario generated by the bracingprogram32 may be presented visually, such as in a drawing file or printed drawing of thebraces16 or of a braceddie10. Before output, thebraces16 may be automatically numbered sequentially from left to right and from top to bottom if not previously numbered in the program.

FIGS. 6-8 show the brace-making machine38 (also referred to as the apparatus) which preferably cuts braces16 from strip stock (not shown). The strip stock is typically made of steel. Strip stock suitable for braces may come in a variety of widths ranging from about ⅝ to 2 inches or more, a variety of thickness ranging from about ⅛ to ¼ inch and lengths, which may be random, ranging from about 8 to 16 feet. Each strip is generally straight, but typically has some curvature along its length in planes both normal to and parallel with the width of the strip.

Brace-makingmachine38 has aframe102 that supports its various components. A portion offrame102 forms ahopper104 that supports a stack of strips of feed material.Hopper104 includesvertical barriers106 separating the hopper from a bed108 formed by a series of rollers110. Thevertical barriers106 are suspended from theframe102 and extend downwards but do not touch the bottom of thehopper104. A gap between thevertical barriers106 and the bottom of thehopper104 is provided so that a single strip of material may slide through the gap while remaining strips are retained in thehopper104.

A series ofpiston assemblies112 are mounted to theframe102 and operable to push a strip of material onto the rollers110.

Referring now toFIGS. 6 and 10, thepiston assembly112 has apneumatic cylinder118 attached to apiston mounting bracket120 for mounting thepiston assembly112 to theframe102. Thecylinder118 drives apiston shaft122 moving within aspacing block124 that keeps the top of thepiston shaft122 in or below the plane of the bottom of thehopper104. Anabutment124 projects above the top of thepiston shaft122 to a height which allows it to engage a single strip of material on the bottom of thehopper104 without contacting a second strip. Actuating thepneumatic cylinder118 causes thepiston shaft122 to extend which causes theabutment124 to push a strip of material onto the rollers110.

Referring again toFIGS. 6-8, and toFIG. 8 in particular, the rollers110 have flanges114 which define a reference edge of the bed108 and prevent the strip of material from being pushed past the reference edge. A series ofguide mechanisms116 are mounted to the other edge of the bed108 opposite the reference edge.

Referring now toFIGS. 6 and 11, theguide mechanisms116 have avertical roller128 held within anangled block130. Thevertical roller128 is attached to theangled block130 with a spring that biases thevertical roller128 towards the front of the brace-makingmachine38. When the strip of material is on the bed108, thevertical rollers128 apply pressure to the edge of the strip to bias the strip of material towards the flanges114 of the rollers110 of the bed108. However, theangled block130 is itself mounted through a spring to aguide base132 so that it is lowered out of the way by the weight and pressure of a strip of material being pushed by thepiston assemblies112 from thehopper104 to the bed108. Theangled block130 moves back upwards to allow thevertical rollers128 to contact the edge of the strip after the strip is on the bed108. To accommodate different widths of strip material despite the limited range of movement of thevertical rollers128, theguide base132 is mounted to theframe102 throughpins134. Athumbscrew136 may be turned to slide theguide base132 along thepins134 to a position appropriate for strips of various widths. The spring biasing of thevertical rollers128 allows them to hold the strip material against the reference edge of the bed108 despite any longitudinal curvature of the strip material in the plane of the width of the material.

Referring again toFIGS. 6-8, andFIG. 8 in particular, a piece of strip stock on the bed108 may be held by either of two clamps. The first is a front clamp located at the front of the bed108.

Referring toFIGS. 6 and 9, thefront clamp138 includes a mountingbracket140 for supporting the various parts of thefront clamp138 and for mounting thefront clamp138 to theframe102. Thefront clamp138 also has awear plate142 that a strip of material to be cut may rest on. A pair of clampingrollers144 pass through thewear plate142 and are attached to aclamp actuator146. Theclamp actuator146, when actuated, pulls the clampingrollers144 towards thewear plate142 to hold a strip of material clamped against thewear plate142. When released, the clampingrollers144 allow the strip of material to slide along thewear plate142 but may be set to keep the strip of material near thewear plate142 to counter any curvature of the strip material tending to lift the strip material off of the bed108. One of the clampingrollers144 is attached to athumbscrew136 that permits the distance between the clampingrollers144 to be altered to accommodate strip materials of various widths.

Referring again toFIGS. 6-8, the second clamp is amaterial feed clamp148 provided as part of amaterial feeder150.Material feed clamp148 is an electromagnetic clamp positioned above the bed108 such that, when activated, it attaches to the strip of material on the bed108. Components of the bed108, particularly the rollers110 may be made of non-ferrous materials, such as brass or bronze, so as to not interfere with the operation of thematerial feed clamp148.Material feed clamp148 is attached to afeeder arm152 driven linearly bymaterial feeder screw154 alongguide156.Material feeder screw156 is in turn driven withmaterial feed servo158 such thatmaterial feed clamp148 is capable of moving in two directions, either advancing or retracting a strip of material along the bed108.Guide156 ensures that thematerial feed clamp148 travels linearly with minimal deviation.

A cuttinghead160 at the front of the bed108 includes a cutting chamber162, acutting tool164 and acutting tool servo166. The cutting chamber162 encloses a space around where the strip material is to be cut and includes achute170 for large bits of material to fall through to a receptacle (not shown). The cutting chamber162 also includes anexhaust port174 for connection to anexhaust unit172. Cuttingtool164 is a plasma torch although other cutting tools may also be used. Cuttingtool164 is powered by a cuttingtool power supply176. Cuttingtool164 is movable on a slide assembly and is attached to cuttingtool servo166 such that, by operation of cuttingtool servo166, cuttingtool164 may be moved across the width of a strip of material placed under it bymaterial feeder150.Cutting tool servo166 may be operated with the strip of material stationary, optionally Alternately, cuttingtool servo166 andmaterial feed servo158 may be operated simultaneously to cut a curve or series of line segments across width of the strip. Cuttingtool vernier screw178 allows the height of thecutting tool164 to be set as required above the strip of material and allows adjustment of that height from time to time as a consumable part of thecutting tool164 is consumed.

The brace-makingmachine38 also hasvarious proximity switches180 and other sensors. For example, two proximity switches (not shown) are provided with eachcylinder118 to determine whether eachcylinder118 is in either its forward or back position. Anotherproximity switch180 is provided near thematerial feed clamp148 to determine whether material is near thefeed clamp148. Anotherproximity switch180 is provided near thecutting tool164 to determine if the strip of material is within a known offset from the centre of thecutting tool164. Two more proximity switches180 are provided near thematerial feed servo158. One of these proximity switches180 indicates whether thematerial feeder150 is in a position representing thefeed servo158 home position. The other indicates whether thefeed servo158 has over-traveled beyond its home position. Two more proximity switches (not shown) are located on the cutting tool slide assembly and determine whether thecutting tool servo166 is in its home position or whether it has over-traveled. Anotherproximity switch180 is located over the bed108 behind thematerial feed servo158 to indicate whether there is a strip of material on the bed108 behind thefeed servo158 home position. Sensors (not shown) are provided, for example, to indicate whether there is sufficient air pressure to operate thecylinders118 or to indicate whether an emergency stop button has been pushed. Other proximity switches or sensors may also be provided. In addition, various wires and switches are also provided as required to operate the various components of the brace-makingmachine38. For example, switches are provided to activate or de-activate theclamp actuator146, to turn the exhaust unit on or off, to turn thecutting tool164 on or off, to advance or retract thecylinders118 and to engage or disengage thematerial feed clamp148. Other controls may also be provided. Many of the components mentioned above are housed within acontrol cabinet182.

Thecontrol cabinet182 also houses some parts of acontrol system500 that controls the brace-makingmachine38.

Referring now toFIGS. 12-14, thecontrol system500 includes a programmable logic controller (PLC)502.PLC502 comprises apower supply504, aCPU506, aservo controller508, acommunications card510, aninput controller512 and anoutput controller514. Multiple controller or communication cards may be used if desired. For example, there may be twoservo controllers508, one for each

servo

158,166.

Communications card

510 connectsPLC502 to a local area network (LAN)516 through the use ofcommunications hub518. TheLAN516 communications hub is a preferred embodiment of thecommunication network36 described above and illustrated inFIG. 3. In one embodiment, theLAN516 makes use of the ethernet protocol but any number of other protocols may be utilized.

Referring now toFIG. 3 and12, thecomputer31 directs the actions of thePLC502. Thecomputer31 preferably communicates with thePLC502 viaLAN516 and thehub518. Thecomputer31 is adapted to store or receive theinput file33 describing the shape of a die and run the bracingprogram32 to produce theoutput file35 describing the number and shape of braces required to brace a particular die (as described in detail above).

In an alternative embodiment (not shown), the functions ofcomputer31 may be distributed between two (or more) computers. One computer may run the bracingprogram32 and a second computer may control thePLC502. In such an embodiment, the second computer may include a database ofoutput files35 containing information on the shape of braces, for example, the shapes of all braces required for a given die. The output files are received from the first computer (which runs the bracing program32) in any suitable manner, such as viaLAN516.

Referring toFIGS. 3 and 12, an operator operatescomputer31 to select or produce theoutput file35 containing information regarding the shape of one or more braces. In one embodiment, theoutput file35 contains all required information for the brace-makingmachine38 to create the braces. Theoutput file35 is downloaded toPLC502. This information is downloaded in the form of a modified data exchange file (DXF). Other data files, not in the DXF format, may also be used to contain the information required for brace-makingmachine38 to cut a brace. Based upon the downloaded information,PLC502 then directs the brace-makingmachine38 to manufacture the required braces. As thecomputer31 is connected toLAN516, it may receive patterns from or transmit patterns to any other device connected toLAN516.

Computer

31 andPLC502 are configured to operate according to a protocol determining what information will be contained in the DXF or other file and how it will be ordered in the file. Depending on the protocol and how information is input to thecomputer31, it orPLC502 or both may be required to perform some data processing operations to produce or use the information in the file which may include runningprogram32 as described earlier. There are numerous options for the protocol that may be used according to a users preference. In one example, the file downloaded toPLC502 contains all information relating to thebraces16 required for a selecteddie10. This information includes the number ofbraces16 to be made, the shape of eachbrace16 and the location of any holes in eachbrace16. The shape of eachbrace16 is defined in the file by a series of co-ordinates, for example X-Y co-ordinates, for the start and end of each line segment forming the shape of the ends of thebrace16, the co-ordinates for the centers of anyholes18 and an overall length of eachbrace16. Also included may be various parameters such as the width of the strip of material for thebraces16, the distance between the cuttingedge14 and interior surface of theknife12, the width or radius of the cut made by thecutting tool164 and the radius ofholes18. According to the protocol, thecomputer31, or anoperator using computer31 will have determined whether anynicks20 pass through the plane of thebraces16 and adjusted the shape of thebraces16 as described in the input file accordingly.Holes18 will be shown in the input file by the location of their centers, but the hole diameter will be included as a parameter. Accordingly,PLC502 performs calculations to determine the required path of thecutting tool164 considering the desired center and diameter of eachhole18 and the radius of a cut made by thecutting tool164 in the course of instructing the

servos

158,166 to cut eachhole18. The shape of the ends of eachbrace16 will be provided as several line segments corresponding with the shape of thecutting edge14 of thedie10. Thus, thecomputer31 may be required to convertbrace16 or die10 shapes originally provided in forms other than a series of line segments.PLC502 is required to account for the distance between the cuttingedge14 and the interior of theknife12 and the radius of cut of thecutting tool164 in the course of instructing the

servos

158,166 to cut the ends of thebraces16. Alternately, thecomputer31 may be required to pre-process the information in the file to account for these differences before downloading the file to thePLC502. Rules are also provided relating to any other features of thebraces16, for example, to account for mounting punches or other items that may also be attached to thebraces16. The protocol may also include rules for tagging, ordering or arranging data, such as in blocks or layers, such thatPLC502 may locate and extract information regarding distinct braces16. The protocol also includes rules regarding the scale and units to be used, for example, that the scale will be1:1 and all units will be inches. Thecomputer31 may also be configured to provide other pre-processing of the input file, for example to check for and correct any discontinuities in the shape of abrace16, to numberdistinct braces16 or to determine the shapes ofbraces16, the location ofholes18, or other aspects of thebraces16 from other information such as information describing thedie10, for example by runningprogram32 as described earlier.

Thecomputer31 may also be used to manually control the brace-makingmachine38. For manual control, thecomputer31 provides an interface through which an operator may view the information provided by the inputs shown inFIG. 13 and other indicators of system performance. Thecomputer31 also allows an operator to direct the operation of the

servos

158,166 ofFIG. 13 or the outputs shown inFIG. 14 individually. For example, the

servos

158,166 may be homed or moved to a selected distance from the home position and the outputs shown inFIG. 14 or others may be turned on or off, advanced or retraced, engaged or disengaged or activated or de-activated. Thecomputer31 also allows an operator to enter commands that may over-ride or modify an automated function on thePLC502. For example, an operator may stop, pause or reset an operation being performed byPLC502 or re-set or respond to alarms. Thecomputer31 converts these various commands entered by an operator into signals directing thePLC502. Thecomputer31 may also provide or alter various machine control parameters stored inPLC502. These parameters may include items such as travel limits for the

servos

158,166, or desired servo speeds. These parameters may also include various offsets such as the distance between theproximity switch180 near thecutting tool164 and the centre of a cut made by thecutting tool164 or between the cuttingtool164

home proximity switch

180 and the reference edge of the bed108. These offsets are used by thePLC502 to convert information from the proximity switches180 to information regarding the actual location of the strip of material being cut, thecutting tool164 or thefeed clamp148.

Referring again toFIG. 12, each component of thePLC502 will now be discussed in more detail.Power supply504 provides the power forPLC502.CPU506 controls the overall processing ofPLC502.Servo controller508 controls cuttingtool servo166 andmaterial feed servo158.Cutting tool servo166 advances or retracts cuttingtool164 andfeed servo158 advances or retractsmaterial feeder150.Communication card510 connectsPLC502 tohub518 and thus to control thecomputer31.Input controller512 controls a plurality of inputs devices as shown inFIG. 13. Each input device determines the status of a component of the brace-makingmachine38. The inputs include a number of proxy switches180 described above which are grouped together in a dashed rectangle withinFIG. 13. Other inputs include anair pressure switch522 and a master control relayemergency stop button524.Air pressure switch522 determines if air pressure is sufficient to operate thecylinders118 or any other component of the bracingmachine38 that is pneumatically powered. Mastercontrol stop button524 detects whether an operator has pressed an emergency stop button and, if so, cuts power to themachine38. Other inputs may be added as desired.

Output controller

514 controls a various components of themachine38, as shown inFIG. 14. Control of these components typically occurs through various ancillary components not shown. For example,clamp actuator146,exhaust unit174, cuttingtool164 and feedclamp148 are all electrically powered. Theoutput controller514 controls these components through various switches or relays.Cylinders118 are pneumatically powered and theoutput controller514 controls them through an appropriate combination of components such as relays, solenoids and valves. Other controls may be added to provide other functions. For example, a printer may be added to place a part or serial number on a label on each brace cut or a cleaner may be added to clean the braces before they leave themachine38. Cleaning and labeling may also occur before a brace is cut.

FIG. 15 shows thecutting process600 performed bycontrol system500. Instep602, thecontrol system500 and brace-makingmachine38 are initialized. This step includes various sub-steps to make thecontrol system500 and brace-makingmachine38 ready for operation. For example,

servos

158 and166 are homed and checks are made to determine if a strip of material is present on the bed108 with its front edge under thecutting tool164, if communications links are open and whether the brace-makingmachine38 is ready for operation. Steps are performed to overcome any initial deficiencies. For example, a piece of strip of material may be loaded if there is none on the bed108 or a strip of material on the bed108 may be moved forward to place its front edge under thecutting tool164 by at least a minimum clearance distance.

Instep604, thePLC502 waits for theoutput file35 to be downloaded. Once a file is received, processing continues to step606 in which information regarding abrace16, which may be a first ornext brace16 to be cut, is extracted. If multiple braces16 are included in the input file to thePLC502, which is theoutput file35 from thecomputer31, thePLC502 will establish an indexing log or counter indicating the total number of braces to be cut. The counter allowsPLC502 to determine atstep620, to be described below, whether more braces need to be cut.

Instep608, the position of thematerial feeder150 is checked to see whether it is over top of a strip of material and far enough away from thecutting tool164 to cut thenext brace16. If both conditions are not satisfied, processing moves to step622 where thematerial feeder150 is moved back to a distance behind thecutting tool164 at least as large as the overall length of thebrace16 to be cut plus a minimum operating clearance. To move thematerial feeder150,front clamp138 is first engaged andmaterial feed clamp148 disengaged so that the strip of material will not move.Material feed servo148 is then operated to move thematerial feeder150 back. Instep624, a check is made to see if thematerial feeder150 was capable of secure sufficient strip material for thenext brace16. The check may include monitoring theproximity sensor180 that determines whether thematerial feeder150 has over-traveled. Over-travel may occur if an operator attempts to cut a brace larger than the maximum travel, less operating clearances, of thematerial feeder150. This possibility may also be avoided by having thecomputer31 orPLC502 check anybraces16 for excess length before attempting to cut them.

Alternately, thecontrol system500 may be adapted to cutlarger braces16 by allowing thematerial feeder150 to re-locate itself in relation to a strip being cut while cutting asingle brace16. In the present embodiment, thematerial feeder150 holds the strip to be cut at only one location while all cuts are made for abrace16.

A check is also made of theproximity sensor180 near thematerial feed clamp148 to see if material is present to be clamped. Material will not be present if the strip of material on the bed108 is too short for thebrace16 to be cut. In this case, the process proceeds to

steps

626 and628 in which the existing material is ejected from the bed108 and a new piece of material is loaded. Step626 may be performed by alerting the operator through thecomputer31 that the strip is too short. The operator then removes the strip of material and then enters an instruction through thecomputer31 indicating that the process may proceed to step626.

Alternately, steps626 and628 may be performed automatically. For the automatic process,material feeder150 is moved so as to be able to grab near the back edge of the strip.Front clamp138 is opened,material feed clamp148 turned on, andmaterial feeder150 is then moved to its farthest forward travel limit. This moves the strip of material to a position in front of where a new strip to be loaded. Thefront clamp138 is then closed, thematerial feed clamp148 opened and thematerial feeder150 returned to its home position.Cylinders118 are advanced to push a new strip onto the bed108.Material feed clamp148 is closed on the new strip and thecylinder118 are retracted. Proximity switches180 are checked to verify that all cylinders advance and retract as required. Thematerial feeder150 is then moved forward by a pre-set distance sufficient to put the front edge if the new strip under thecutting tool164 which also ejects the old strip through the front of the cutting chamber162.

Instep608, the current position of thematerial feeder150 is also checked to make sure the rear or front travel limits will not be reached when moving the steel during a cut. For this check, the peak to peak distance of the head cut is added to the current position of thematerial feeder150 and the result checked to make sure that the limits of thematerial feeder150 will not be reached. If a limit would be reached, then thematerial feeder150 is moved without moving the feed stock as required so that the cut may be made without requiring thematerial feeder150 to be repositioned relative to the feed in the middle of a cut.

When the checks instep608 have been satisfied, the process proceeds to step610. Instep610 the head, or front edge, of thebrace16 is cut. To make the cut, thePLC502 generates a profile of the cut and array of instructions to the

servos

158,166. The

servos

158,166 are moved to the first co-ordinate in the profile. Thecutting tool164 is then turned on and the

servos

158,166 are run through their profile moves. Thecutting tool164 is then turned off.

In

steps

612 and614, thecontrol system500 checks whether theholes18 are required, and if so, cuts theholes18. To facilitate checking whether there are any holes to be cut, thePLC502 notes the total number of holes to be cut and maintains a counter as eachhole18 is cut. Each holes18 is cut in a manner similar to that described for the cutting the head of thebrace16. When all holes18 are cut, the process proceeds to step616 where the tail of thebrace16 is cut in a manner similar to how the head of thebrace16 was cut. As the tail is cut, thebrace16 falls through the front of the cutting chamber162.

After abrace16 is cut,material feeder150 is moved forward to a clearance distance sufficient to ensure that the head of thenext brace16 may be cut. The clearance distance accounts for the width of the cut made by thecutting tool164. The clearance distance also accounts for the possibility that the tail cut on the last brace may have extended forwards towards the end of the cut and backwards from the reference edge of the bed108. In this case, a solid width of material is not left under the path of travel of thecutting tool164 and theproximity sensor180 near thecutting tool164 can not be used to determine by how much the strip needs to be advanced to correct the problem.

The clearance distance may be set in the protocol and braces16 that would cause a problem despite the clearance distance would not be allowed. Alternatively, the total length ofbrace16 information in the input file may be used to establish a clearance for each brace. Alternatively, thecomputer31 may compare the tail and head cut shapes ofbraces16 and, with consideration for the width of cut, determine a distance for thematerial feeder150 to move instep618 and include this in the input file. In this way, strip material is saved since the PLC520 may reduce the clearance distance in cases where the tail of onebrace16 has a shape similar to the head of thenext brace16 to be cut.

Afterstep618, the process continues to step620 where the index is consulted to see if there are more braces to cut. If so, then the process returns to step606. If not, then the process returns to step604. The process is thus continuous, but may be terminated by the operator through thecomputer31 when the operator is finished cutting braces.

Although the invention has been described with reference to certain specific embodiments, various modifications can be made without departing from the spirit and scope of the invention as described in the following claims. In particular, but without limitation, theprogram32 may be modified, other forms of cutters may be used, modified systems may be used to move the strip of material and the cutter, the configuration of the machine may be changed, different types of clamps, actuators, guides or piston assemblies may be used, other parts may be substituted for parts suitable for performing the same tasks, the protocol may be changed and the series of steps performed may be modified. Further, although the systems and methods have been described for use in making braces for dies, they, or parts of them, may be adapted or used in other situations where a piece of strip stock is designed or cut to fit to a boundary.