US20090071223A1

US20090071223A1 - Staged Tooling Technology

Info

Publication number: US20090071223A1
Application number: US11/857,825
Authority: US
Inventors: Bryan L. Rogers; Thomas S. Duppong; Mike J. McNertney; William J. Klein
Original assignee: Wilson Tool International Inc
Current assignee: Wilson Tool International Inc
Priority date: 2007-09-19
Filing date: 2007-09-19
Publication date: 2009-03-19
Also published as: WO2009038998A2; WO2009038998A3

Abstract

The invention involves staged press brake tooling combinations. In some embodiments, the invention provides a staged press brake setup. In other embodiments, the invention provides a staged quick-change multiple forming recess press brake die.

Description

FIELD OF THE INVENTION

The present invention relates generally to tooling for industrial presses. Specifically, this invention relates to tooling for press brakes, methods of fabricating sheet metal and other workpieces, and tooling setups for press brakes.

BACKGROUND OF THE INVENTION

A variety of presses are used in fabricating sheet metal and other workpieces. Press brakes are particularly useful. Press brake tooling can play a significant role in minimizing setup, reducing WIP, increasing throughput, and minimizing waste—the goals of lean manufacturing.
Most of today's original equipment manufacturers (OEMs) and contract manufacturers have embraced the principles of lean manufacturing. Many of the obvious offenders—the most wasteful processes and excess inventory—have been revamped and streamlined. But reaching the next level of lean is more challenging. It requires manufacturers to dig deeper, carefully examining each piece of the manufacturing puzzle for potential improvements.
In the area of press brake tooling, a closer look reveals room for improvement. Press brake tools, in fact, can play a very significant role in minimizing setup time, reducing work-in-progress (WIP), increasing throughput, and minimizing waste.
As OEMs move to reduce inventory, and continue to call for just-in-time (JIT) manufacturing, small-batch press brake runs are increasingly common.
Smaller does not necessarily mean easier or more efficient, though. Taking into account the setup time for multiple bends, it can be difficult to justify the expense of complex short-run jobs.
Thus, it would be desirable to provide staged press brake tooling that can make small runs cost-effective, e.g., by simplifying complex bending sequences and allowing each part to be handled only once. Staged bending is the execution of multiple bends in a single press brake setup. In staged bending, all the bends on a single part can be made in succession, using a single setup.
It would be desirable to provide staged, quick-change tooling. Further, it would be desirable to provide staged European-style press brake tooling, preferably based on common theoretical sharp dimensions, being quick-change tooling, or both. Finally, it would be desirable to provide a staged, quick-change die with a plurality of different forming recesses.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a press brake setup in accordance with certain embodiments of the invention.

FIG. 2 is a side end view of a press brake setup in accordance with certain embodiments of the invention.

FIG. 3 is a perspective view of a press brake setup in accordance with certain embodiments of the invention, where the tools on the upper and lower beams are shown in open position.

FIG. 4 is a perspective view of the press brake setup of FIG. 3, where the tools are shown in closed position.

FIG. 5A is a broken-away detail view of the tip of a press brake tool in accordance with certain embodiments of the invention.

FIG. 5B is a broken-away detail view of the tip of another press brake tool in accordance with other embodiments of the invention.

FIG. 6 is a side end view of a press brake setup in accordance with certain embodiments of the invention.

FIG. 7 is a side end view of a die mounted on a rail in accordance with certain embodiments of the invention.

FIG. 8 is a side end view of a die in accordance with certain embodiments of the invention.

FIG. 9 is a side view of the die of FIG. 8, with the die rotated 90° from the position shown in FIG. 8.

FIG. 10 is a perspective view of a die mounted on a rail in accordance with certain embodiments of the invention.

FIG. 11 is a perspective view of the rail-mounted die of FIG. 10, with the die being rotated 90° from the position shown in FIG. 10 such that a ridge of the rail is received in a second locating channel of the die.

FIG. 12 is a side end view of a die mounted on a rail in accordance with certain embodiments of the invention.

FIG. 13 is a side end view of the rail-mounted die of FIG. 12, with the die being rotated 90° from the position shown in FIG. 12 such that a ridge of the rail is received in a second locating channel of the die.

FIG. 14 is a perspective view of a rail on which multiple dies are mounted in accordance with certain embodiments of the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The following detailed description is to be read with reference to the drawings, in which like elements in different drawings have like reference numerals. The drawings, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of the invention. Skilled artisans will recognize that the given examples have many useful alternatives, which fall within the scope of the invention.
Staged bending is the execution of different types of bends on a workpiece using a single press brake setup. In staged bending, a plurality of (optionally all of the) different bends on a single part can be made in succession, using a single setup.
Consider the manufacturing process for a cabinet component (this is merely an example for purposes of discussion). The bending process may require a 30-degree bend with hem, an offset bend, a 60-degree bend, and four 90-degree bends. Using conventional methods, an operator would set up the 30-degree bend with a 30-degree hemming punch and die and perform the bend on all of the parts, handling each part one at a time. Then, the operator would either remove the 30-degree hemming punch and die or reposition them so the top and bottom tool would not collide. Next, the operator would set up an offset punch and a corresponding die and make the offset bend on all of the parts, again handling each part another time. Once the offset bends were complete, the operator would either remove the offset punch and die or reposition them so the top and bottom tool would not collide. Next, the operator would set up a 60-degree punch and die and make this bend on all of the parts, handling the parts for the third time. When finished with this bend, the operator would have to either remove or reposition the 60-degree punch and die so the top and bottom tool would not collide. Finally, the operator would set up a 90-degree punch and die and complete the four 90-degree bends, handling the parts for the fourth time. This conventional manufacturing method requires the operator to complete four separate setups and create or load four separate programs.
In contrast, by using staged bending to bend the same part, the operator would set up the 30-degree hemming punch and die, the offset punch and die, the 60-degree punch and die, and the 90-degree punch and die all at the same time, creating or loading only one program. These tools would be set up in progressive order. On the same blank, the operator would complete the 30-degree hemming, the offset bending, the 60-degree bending, and the four 90-degree bending operations, thus achieving a completed component. The part would only need to be handled and set up once.
Due to the considerable setup and programming time required in conventional manufacturing methods, it is common to run large batch sizes to gain the economies of scale needed to absorb the non-value-added time (setup, teardown, and part handling). With staged bending, much smaller production runs are feasible, because setup, teardown, and part handling are eliminated or minimized. This allows the fabricator to make what is needed when it is needed, reducing both WIP and excess inventory.
The present invention provides several advantageous staged tooling technologies. These technologies allow a press brake to be equipped with multiple pairs of tools, of which at least one pair (e.g., at least one mateable punch and die set) is adapted to create a different bend than at least one other pair. Even though the present setup has different tool pairs with different angles, different radii, etc., the tools do not collide.
In some embodiments, all the tools (e.g., punches and dies) of a common height series (e.g., all the tools in a desired combination) have the same “shut height” 700 (without material between the mateable tools). Reference is made to FIG. 6.
Turning to FIG. 1, it can be seen that in some embodiments, different tool pairs on a single press are adapted to create different bends. In these embodiments, at least one of the upper tools 100 has a tip configuration (e.g., shape) different from that of another upper tool. More will be said of this later.
In the present embodiments, a plurality of (preferably a majority of, perhaps optimally all of) the tool pairs on the press brake PB are adapted to come together (or “mate”) at the same time. Thus, for each such mateable tool pair, the upper and the lower tools preferably have the same shut height 700 (or at least substantially the same shut height). For setups where punches are on the upper beam and dies are on the lower beam, the punches preferably contact (e.g., bottom out in) corresponding dies at the same time (i.e., when the upper and lower beams are brought together—by moving the upper beam toward the lower beam, by moving the lower beam toward the upper beam, or both).
One group of embodiments provides a staged press brake system including a press brake PB having upper 125 and lower 145 beams. In these embodiments, the system (or “setup”) includes a plurality of upper press brake tools 100 mounted in respective tool holders TH on the upper beam 125. Preferably, each of these tools 100 has a tang TG, and the tangs are received in respective tool holders.
As noted above, at least one of the upper tools 100 has a tip configuration different from that of another upper tool. FIGS. 1-4 and 6 show exemplary embodiments of this nature. The tip configurations of such tools can have different angles, different radii, etc.
In some embodiments, the tip of one tool has two converging surfaces CV separated by a certain angle, while the tip of another tool in the same combination (e.g., in the same setup) has two converging surfaces CV separated by a different angle. These angles can optionally be different by at least one degree, at least 2 degrees, at least 5 degrees, at least 10 degrees, at least 25 degrees, or more. Additionally or alternatively, the tip of one tool can have a first radius, while the tip of another tool has a different radius. These radii can optionally be different by at least 0.001 inch, at least 0.002 inch, at least 0.01 inch, or more.
In some embodiments, the setup includes at least three pairs of mateable tools. These embodiments, for example, can include a first punch and die pair adapted to make a first bend, a second punch and die pair adapted to make a second bend, and a third punch and die pair adapted to make a third bend. The first, second, and third bends are all different types of bends. These can be any desired bend types. As just one possibility, these bends can be three different bends selected from the group consisting of a 30-degree bend, an offset bend, a 60-degree bend, a 90-degree bend, and a hemming bend. Other possibilities include large-radius bending and other acute-angle bends (such as 45-degree bending, 75-degree bending, or 85-89 degree bending, to name just a few examples). The tool combination can also include one or more flattening punches, if desired. Many other possibilities will be apparent to skilled artisans given the present teaching as a guide.
In the embodiments shown in FIGS. 1-4 and 6, there is an upwardly facing load-bearing shoulder LB on only one side of the tang TG. This is perhaps best seen in FIGS. 2 and 6. Preferably, each such load-bearing shoulder LB contacts (e.g., has an upwardly facing surface SS that contacts) a downwardly facing force-transmitting surface LD of a tool holder TH. The tool 100 can optionally have a second shoulder on the other side of the tang, but in the present embodiments the second shoulder is not a load bearing shoulder (i.e., it does not receive a downward pressing force from the tool holder, rather it is spaced downwardly from the bottom end of the adjacent clamp CL on the tool holder TH). In some cases, the top end TE of the tang TG is spaced downwardly from the tool holder's confronting downwardly facing surface DF. There are, however, embodiments where these features are not present.
Referring to FIGS. 2 and 6, it can be seen that the illustrated tang TG configuration involves a safety recess formed in one side of the tang. In setups having one or more tools of this nature, the safety recess can optionally receive a lip of a pivotable clamp of a tool holder. In FIGS. 2 and 6, the safety recess is a slot formed in the side of the tang. The slot has a downwardly facing shoulder adapted to engage, as a safety measure, an upwardly facing shoulder of the lip on a clamp CL. Other tang and clamp configurations can be used in the present setup, as either an alternative to, or in combination with, the illustrated tang and clamp configurations.
In FIGS. 1-6, each upper tool 100 has a downwardly facing tip TP comprising two downwardly converging surfaces CV. Here, two planes CVP lying respectively on planar portions of the two converging surfaces CV intersect at a tool theoretical sharp location IP. The tool theoretical sharp location may be located beyond the tip of a given tool (see FIG. 5A), or it may be at the end of the tool's tip (see FIG. 5B).
Many different tip configurations can be used. A variety of useful European-style punches are shown in the Wilson Tool publication entitled “European Style Press Brake Tooling” (February 2006), the salient teachings of which are incorporated herein by reference. The tools shown in this publication are commercially available from Wilson Tool (White Bear Lake, Minn., U.S.A.).
In the present embodiments, a common vertical distance 99 separates the tool theoretical sharp location IP and the upwardly facing surface SS of the load-bearing shoulder LB for a plurality of (preferably a majority of, perhaps optimally all of) the tools 100 in the combination (when the upper and lower tools are in closed positions, as shown in FIG. 6). The term “common” here means the distance is the same or substantially the same for the tools in question. For embodiments where the upper tools are punches, this distance 99 is the “punch staged height.”
In some of the present embodiments, the tooling setup includes at least one large-radius bending tool. Here, the large-radius bending tool and its corresponding die preferably are configured to have the same shut height (or substantially the same shut height) as the other tools on the press brake. Preferably, the same is true of any flattening tools that may be included in the tooling setup.
For embodiments where different tool pairs have at least substantially the same shut height, any variance in the actual shut heights preferably is less than 0.010 inch.
The present setup also includes a plurality of press brake dies 10, 10′. Preferably, each die 10, 10′ is mounted on a rail 20 carried by the lower beam. The rail 20 can optionally be mounted on a die holder 30 secured to the lower beam. The present staged setup does not require any special shims or risers. Thus, the bottom of each die preferably sits directly on the rail, and the bottom of the rail preferably sits directly on the die holder.
As is perhaps best seen in FIGS. 7 and 8, each die 10, 10′ preferably has a bearing face 15FB, 15SB with a bearing base 15FBB, 15SBB and a locating recess (e.g., channel) 15FL, 15SL in which a locating ridge 25 of the rail 20 is received. In the illustrated embodiments, each bearing base is defined by two flush, planar surfaces separated by a single locating recess. Each illustrated die has only one locating recess in the/each bearing face, although this is not strictly required. Furthermore, each illustrated locating recess has a cross section (taken perpendicular to the die's longitudinal axis LA) that is rectangular, although other configurations can be used.
In the present setup embodiments, each die 10, 10′ also has a workpiece-contact face 15FC, 15SC with an upwardly open forming recess 15FR, 15SR. In the illustrated embodiments, each forming recess 15FR, 15SR is bounded by two downwardly convergent surfaces CS. Here, two planes P lying respectively on planar portions of the two convergent surfaces CS intersect at a die theoretical sharp location FTS, STS. Preferably, a shared vertical distance 300 separates the die theoretical sharp location FTS, STS and the bearing base 15FB, 15SB (a base surface 15FBB, 15SBB thereof) for a plurality of, a majority of, or all of the dies 10, 10′ in the present setup. The term “shared” here means the distance is the same or substantially the same for the dies in question.
In FIG. 6, it can be appreciated that the dies 10′, the rail 20, and the die holder 30 are configured such that the “closed height” 900 for each operatively positioned tool pair is the same (or substantially the same). Similarly, in the present setup embodiments, the die staged height 1700 preferably is the same or substantially the same for a plurality of the dies, a majority of the dies, or all of the dies. Reference is made to FIG. 7.
In some of the present embodiments (see FIG. 6), the tool holders TH on the upper beam have a centerline 500 that extends vertically downwardly and passes through all of the following: (a) the downwardly facing force-transmitting surface LD of each tool holder, (b) the upwardly facing load-bearing shoulder LB (and its upwardly facing surface SS) of each tool, (c) the tool theoretical sharp location IP of each tool, and (d) the operative die theoretical sharp location FTS, STS of each die. For embodiments involving a die with multiple forming recesses 15FR, 15SR, the term “operative die theoretical sharp location” refers to the theoretical sharp location of the forming recess that is operatively positioned (the operative forming recess will typically be upwardly facing, i.e., facing the upper beam). This is perhaps best understood by referring to FIG. 7, which illustrates a staged 2-V die.
In embodiments like those of FIG. 6, the operative locating recess 15FL, 15SL of each die 10, 10′ is not directly aligned with the machine's centerline 500. Rather, the operative locating recesses (e.g., channels) of the illustrated dies are spaced from this centerline. In some embodiments of this nature, the (or each) locating recess 15FL, 15SL on each die has a width 800, 810, and a plurality of (preferably a majority of, or all of) the dies have a common die locating dimension DLD. This is perhaps best appreciated by referring to FIGS. 7 and 8. For purposes of the present disclosure, the “die locating dimension” is defined as the distance between the centerline 500 of the press brake PB and a midpoint of the width 800, 810 of the operative locating recess 15FL, 15SL. For embodiments involving a die with multiple locating recesses, the term “operative locating recess” refers to the locating recess that is operatively positioned (the operative locating recess will typically receive the ridge 25 of the rail 20).
Thus, in certain embodiments, the tools (e.g., punches) and dies when mated all have a common shut height 700. For purposes of this disclosure, the “shut height” is defined as the vertical distance between the operative bearing face 15FB, 15SB (a base surface 15FBB, 15SBB thereof) and the upwardly facing load-bearing shoulder LB (an upwardly facing load-bearing surface SS thereof) of a closed tool and die pair.
As noted above, in the present embodiments, at least one mateable tool and die pair is adapted to create a first bend, and at least one other mateable tool and die pair is adapted to create a second bend. The first and second bends here are different. (It is to be appreciated that the terms “first bend,” “second bend,” and the like do not require those bends to be made in any particular sequence. For example, the “first bend” could be made in a workpiece after the “second bend” has been made in the workpiece.) In some cases, the first or second bend is a 90-degree bend. In certain embodiments, the first and second bends are two different bends selected from the group consisting of a 90-degree bend, a 60-degree bend, and a 30-degree bend. The first bend can optionally be a 90-degree bend, while the second bend is a 30-degree bend. This is merely one example, however.
Some embodiments involve a first mateable tool and die pair adapted to create a first bend, a second mateable tool and die pair adapted to create a second bend, and a third mateable tool and die pair adapted to create a third bend. Again, the first, second, and third bends are all different. For instance, the first bend can optionally be a 90-degree bend, while the second bend is a 60-degree bend, and the third bend is a 30-degree bend. This particular example, however, is not required.
The present setup can have virtually any number of different bending stations. Generally, each bending station includes at least one mateable punch and die set. FIGS. 3 and 4 show one exemplary setup having three bending stations. Here, each bending station includes a mateable punch and die pair. Each of these bending stations is adapted to make a different bend than the other two stations.
In some embodiments, at least one of the dies 10, 10′ has a working height WH different from that of another die 10, 10′. This is perhaps best appreciated by referring to FIGS. 1 and 7. The working height WH of a die 10, 10′ is defined as the distance between its operative bearing face 15FB, 15SB (a base surface 15FBB, 15SBB thereof) and its operative workpiece-contact face 15FC, 15SC. In some cases, at least one of the dies 10, 10′ has a working height WH that is greater than that of another die by at least 1/32 inch, by at least 1/16 inch, by at least ¼ inch, or more.
In certain embodiments, the setup includes at least one die (or a plurality of dies) having a forming recess with a radiused bottom. In some cases, planar portions of two convergent surfaces CS are connected by a radiused valley section RVS. This is the case with the forming recesses 15FR, 15SR shown in FIGS. 8 and 9. Each of these forming recesses would have a greater depth if the two convergent surfaces CS converged at constant angles over their whole length until reaching a vertex at the die theoretical sharp location FTS, STS rather than being connected by a radiused valley section RVS. In FIG. 7, each forming recess 15FR, 15SR comes to a sharp vertex, rather than terminating at a radiused valley section. The present embodiments can include dies with any combination of sharp Vs, rounded Vs, etc.
In some of the present setup embodiments, a plurality of the tool holders TH on the press brake PB have pivotable clamps CL. This is perhaps best seen in FIGS. 1, 2, and 6. Useful European style tool holders are described in U.S. Pat. No. 6,003,360, the salient teachings of which are incorporated herein by reference. Generally, each clamp CL is pivotable about a horizontal axis. In FIG. 2, it can be seen that the tool holder TH has a downwardly extending support plate 114. This support plate 114 has a downwardly facing shoulder that is adapted to engage the upwardly facing load-bearing shoulder LB of a tool (e.g., a punch). This downwardly facing shoulder defines the surface LD. In the illustrated embodiments, the tool holder TH has pivotable clamps CL spaced from both sides of the support plate 114. This, however, is not required.
In one group of embodiments, the tool holders TH (or at least some of them) have seating mechanisms that, in response to clamping movement of the tool holders, move upwardly facing shoulders LB of the tools 100 into contact with respective downwardly facing force-transmitting surfaces LD of the tool holders. Useful seating mechanisms of this nature are described in U.S. patent applications Ser. Nos. 11/178,977 and 11/230,742, the salient teachings of which are incorporated herein by reference.
Thus, some embodiments of the invention involve a staged press brake system (e.g., a setup) that includes a press brake PB. Other embodiments, though, simply provide a combination of staged tools 100, 10, 10′ for a press brake system. Preferably, the tooling combination is adapted for use on a press brake with upper and lower beams. The tooling combination includes a plurality of press brake tools (e.g., punches) 100 and a plurality of press brake dies 10, 10′.
Commonly, the tools 100 are upper tools adapted to be mounted in respective tool holders on the upper beam 125. As noted above, each tool 100 has a tang TG, and the tangs are adapted for receipt in respective tool holders TH. In the present tooling combination, at least one of the tools 100 has a tip configuration different from that of another tool of the combination. This was explained above in connection with the setup embodiments.
In some of the present embodiments, there is a load-bearing shoulder LB on only one side of the tang TG of each tool 100. Preferably, each such shoulder LB (e.g., a surface SS thereof) is adapted to contact a downwardly facing force-transmitting surface LD of a tool holder TH when the tools 100 are operatively mounted in respective tool holders. In certain embodiments, each tool 100 (or at least one tool 100) has a tip TP comprising two converging surfaces CV, and two planes CVP lying respectively on planar portions of these two converging surfaces intersect at a tool theoretical sharp location IP. In the present embodiments, a common distance 99 separates the tool theoretical sharp location IP and the load-bearing shoulder LB (surface SS thereof) for all (or at least a plurality of) the tools 100 in the tooling combination.
In connection with the dies 10, 10′, each one preferably is adapted to be mounted on a rail 20. In the illustrated embodiments, the die rail 20 is mounted on a die holder 30, which is supported by the press brake's lower beam 145. Preferably, each die 10, 10′ has a bearing face 15FB, 15SB with a bearing base 15FBB, 15SBB and a locating recess (e.g., channel) 15FL, 15SL. Each locating recess is adapted to receive a locating ridge 25 of the rail 20. And each die 10, 10′ preferably has a workpiece-contact face 15FC, 15SC with a forming recess 15FR, 15SR, which in some cases is bounded by two convergent surfaces CS. As noted above, two planes P lying respectively on planar portions of such two convergent surfaces CS intersect at a die theoretical sharp location FTS, STS. As with the setup embodiments described above, a shared distance 300 separates the die theoretical sharp location FTS, STS and the bearing face 15FB, 15SB (a base surface 15FBB, 15SBB thereof) for all the dies 10, 10′ (or at least a plurality of the dies) in the present tooling combination.
In the illustrated embodiments, each workpiece-contact face 15FC, 15SC has a single forming recess. In the figures, two flush, planar surfaces are separated by each forming recess. These features, however, are not required in all embodiments.
In the tooling combination embodiments, the tools and dies, when held in a closed (i.e., mated) position, preferably all have a common shut height 700. It is possible, though, for the tooling combination to include some tools that have a smaller shut height than that of the staged tools in the combination. In such cases, the staged tools can be used to perform staged bending, without actually using the shorter tools (the shorter tools would not collide).
In some of the tooling combination embodiments, at least one of the dies 10, 10′ has a working height WH different from that of another die. This is perhaps best seen in FIG. 1. In some cases, at least one of the dies 10, 10′ has a working height WH that is greater than that of another die by at least 1/32 inch, by at least 1/16 inch, by at least ¼ inch, or more. This, however, is not required.
In certain embodiments, the tooling combination includes at least one die having a forming recess with a radiused bottom. For example, planar portions of two convergent surfaces CS can be connected by a radiused valley section RVS. Each such forming recess 15FR, 15SR would have a greater depth if the two convergent surfaces CS converged at constant angles over their whole length until reaching a vertex at the die theoretical sharp location FTS, STS, rather than being connected by a radiused valley section. As noted above, one or more of the forming recesses can alternatively have two convergent surfaces CS that come to a sharp vertex.
In the present tooling combination, at least one mateable tool and die pair is adapted to create a first bend, and at least one other mateable tool and die pair is adapted to create a second bend. As already explained, the first and second bends are different. For example, the first and second bends can optionally be two different bends selected from the group consisting of a 90-degree bend, a 60-degree bend, a 30-degree bend, an offset bend, and a hemming bend. However, this is by no means required.
In some embodiments, the tooling combination includes a first mateable tool and die pair adapted to create a first bend, a second mateable tool and die pair adapted to create a second bend, and a third mateable tool and die pair adapted to create a third bend. Here again, the first, second, and third bends are all different types of bends.
Thus, the present tooling combination can include two mateable tool pairs, three mateable tool pairs, or more mateable tool pairs. Many variants of this nature will be apparent to skilled artisans given the present teaching as a guide.
In one group of embodiments, the tooling combination includes at least one tool with a seating mechanism. The seating mechanism here is adapted to seat the load-bearing shoulder LB of the tool 100 against a downwardly facing force-transmitting surface LD of a tool holder TH in response to a clamping movement of the tool holder. Tools with useful seating mechanisms are described in U.S. patent application Ser. No. 11/451,148, the salient teachings of which are incorporated herein by reference.
Some embodiments provide the tooling combination together with a press brake. Setup embodiments of this nature have already been described. As noted above, in some of these embodiments, one or more (optionally each) of the tool holders comprises a pivotable clamp CL. This is best seen in FIGS. 1, 2, and 6.
The invention also provides fabrication methods involving a press brake with upper and lower beams. The method involves providing a plurality of press brake tools. Each tool has a tang, and at least one of the tools has a tip configuration different from that of another tool. In some of these embodiments, there is a load-bearing shoulder on only one side of the tang of each tool. Preferably, at least one tool (optionally each tool) has a tip comprising two converging surfaces CV, and two planes lying respectively on planar portions of these two converging surfaces intersect at a tool theoretical sharp location. As already explained, a common distance 99 separates the tool theoretical sharp location and the load-bearing shoulder (surface SS thereof) for a plurality of, a majority of, or all of the tools 100.
The present method also involves providing a plurality of press brake dies. Each die 10, 10′ has a bearing face 15FB, 15SB with a bearing base 15FBB, 15SBB and a locating recess (e.g., channel) 15FL, 15SI. Each die 10, 10′ also has a workpiece-contact face 15FC, 15SC with a forming recess 15FR, 15SR, which in some cases is bounded by two convergent surfaces CS. As noted above, two planes P lying respectively on planar portions of such two convergent surfaces intersect at a die theoretical sharp location FTS, STS. Preferably, a shared distance 300 separates the die theoretical sharp location FTS, STS and the bearing base 15FB, 15SB (a base surface 15FBB, 15SBB thereof) for a plurality of, a majority of, or all of the dies 10, 10′.
In the present method, an arrangement of tools 100 and dies 10, 10′ is provided on the press brake PB by: (i) mounting the tools 100 in respective tool holders TH of the upper beam 125, e.g., such that the load-bearing shoulders LB of the tools confront downwardly facing force-transmitting surfaces LD of respective tool holders, and (ii) mounting each die 10, 10′ on a rail 20 carried by the lower beam 145 such that the locating recess 15FL, 15SL of each die receives a locating ridge 25 of the rail.
A workpiece is positioned between the upper tool and the die of a first mateable tool set, and a first bend is made in the workpiece WP by bringing the upper 125 and lower 145 beams of the press brake PB together so as to deform the workpiece between the upper tool and die of the first mateable tool set. Then, without changing the arrangement of tools and dies on the press brake (i.e., without changing the setup), the workpiece is positioned between the upper tool and die of a second mateable tool set, and a second bend is formed in the workpiece WP by bringing the upper 125 and lower 45 beams together so as to bend the workpiece between the upper tool and die of the second mateable tool set. The first and second bends here are two different types of bends.
In some of the present embodiments, the method further includes using a third tool set to make a third bend in the workpiece WP. In such cases, the first, second, and third bends are all different types of bends. As just one example, the first bend can be a 90-degree bend, the second bend can be a 60-degree bend, and the third bend can be a 30-degree bend. Many other bend combinations, of course, can be used, depending upon the particular part being fabricated.
The invention also provides a group of embodiments involving a staged quick-change die. In some of these embodiments, the die 10 has multiple forming recesses, e.g., multiple Vs. Reference is made to FIGS. 7-14. Here, the die 10 has two Vs, and the Vs are on two respective faces of the die. Preferably, these two faces are perpendicular (or at least generally or substantially perpendicular) to each other. This, however, may not be the case with all die configurations.
The term “V” can refer to a V-shaped recess with a sharp vertex, a V-shaped recess with a radiused bottom, etc.
One exemplary manner in which the die can be manufactured is by milling the tool from a tool steel billet. The billet, for example, can be milled to a near net shape. After milling, the tool can be ground on all working surfaces. After grinding, the part can either be milled or cut with a saw to lengths. Once the tools have been milled, ground and cut to length, the tool can optionally be heat treated to a desired heat-treat specification. The die (in accordance with one manufacturing method) is then ready for sale. Skilled artisans will be familiar with other manufacturing methods that can be used.
Referring to FIG. 8, the illustrated die 10 has a first bearing face 15FB and a first workpiece-contact face 15FC. Here, the first bearing face 15FB and the first workpiece-contact face 15FC are on opposed (i.e., opposite) sides of the die 10. In FIG. 8, these two faces 15FB, 15FC are parallel (or at least generally or substantially parallel) to each other.
The illustrated die 10 has a generally square cross section (in a plane perpendicular to the longitudinal axis LA of the die). This, however, is not required. For example, the die can alternatively have a generally rectangular cross section. Or the cross section can have various other polygonal shapes. The die can alternatively have a more irregular cross-section.
The first bearing face 15FB includes a first bearing base 15FBB and a first locating recess (e.g., channel) 15FL. In the illustrated embodiments, the first bearing base 15FBB comprises two wall sections separated by the first locating recess 15FL. These two wall sections are shown as being flush, planar wall sections, although this is not strictly required.
The present die 10 is a quick-change die, which can be mounted on a rail 20 (see FIGS. 7 and 10-14). Thus, the illustrated die 10 can be mounted by placing the first bearing base 15FBB on the rail 20 such that a ridge 25 of the rail is received in the die's first locating recess 15FL. The illustrated ridge 25 is elongated in the longitudinal direction, and it has a rectangular cross section (in a plane perpendicular to the longitudinal axis LA). The ridge 25 projects upwardly from the two surfaces (shown as being flush, planar surfaces) that are separated by the ridge. In the illustrated embodiments, the first locating recess (e.g., channel) 15FL has a rectangular cross section (taken in a plane perpendicular to the die's longitudinal axis). However, this is not strictly required.
Referring to FIGS. 2, 7, 12, and 13, it can be seen that when the die is mounted on the rail, there preferably is at least some separation, e.g., a gap 333, between the top of the rail's ridge 25 and the confronting end surface ES of the locating recess in which the ridge 25 is received. The lateral dimension of the ridge 25, however, preferably fits snuggly within the width of the locating recess.
The first workpiece-contact face 15FC has therein formed a first forming recess 15FR. In the illustrated embodiments, this forming recess 15FR is V-shaped or generally V-shaped. However, this recess can be provided in a variety of different shapes, depending upon the particular bend desired.
In FIG. 8, the first forming recess 15FR is bounded by two converging surfaces CS, preferably such that two planes P lying respectively on planar portions of the two converging surfaces CS intersect at a first theoretical sharp location FTS. In the embodiment of FIG. 8, the first forming recess 15FR terminates in a radiused valley section RVS. Thus, the first theoretical sharp location FTS is spaced from (so as to be closer to the first bearing base 15FB than is) the bottom of the radiused valley section RVS. In other cases, the first forming recess 15FR terminates in a sharp vertex at the first theoretical sharp location FTS. Reference is made to FIG. 7.
For purposes of the present disclosure, the term “first theoretical sharp distance” FTSD is defined as the distance between the first bearing base 15FB (the base surface 15FBB thereof) and the first theoretical sharp location FTS. Reference is made to FIG. 9.
In the present embodiments, the die 10 has a second bearing face 15SB and a second workpiece-contact face 15SC. These two faces 15SB, 15SC are on opposed sides of the die. In the illustrated embodiments, these two faces 15SB, 15SC are parallel (or at least generally or substantially parallel) to each other.
The second bearing face 15SB includes a second bearing base 15SBB and a second locating recess (e.g., channel) 15SL. In the illustrated embodiments, the second bearing base 15SBB comprises two wall sections separated by the second locating recess 15SL. These two wall sections are shown as being flush, planar wall sections. However, this is not strictly required.
The second workpiece-contact face 15SC has therein formed a second forming recess 15SR. Here, the recess 15SR is generally V-shaped and is bounded by two convergent surfaces CS. Preferably, two planes P lying respectively on planar portions of these two convergent surfaces CS intersect at a second theoretical sharp location STS.
The term “second theoretical-sharp distance” STSD is defined herein as the distance between the second bearing base 15SB (the base surface 15SBB thereof) and the second theoretical sharp location STS. This is shown in FIG. 9.
In some embodiments, the first 15FR and second 15SR forming recesses have different sizes (e.g., different widths). For example, the die 10 can have two Vs of different size. In FIG. 7, for example, the first forming recess 15FR is larger (e.g., wider and/or deeper) than the second forming recess 15SR. The situation, of course, can be reversed. That is, the second forming recess can be larger than the first forming recess. In the present embodiments, the first forming recess 15FR has a first width, the second forming recess 15SR has a second width, and the first and second widths are different, yet the die 10 is dimensioned such that the first FTSD and second STSD theoretical-sharp distances are the same (or at least substantially the same). This dimensioning feature makes it possible to use either forming recess on the die with a staged tooling set-up.
The configurations of the forming recesses 15FR, 15SR can be varied to accommodate the particular bends desired. As noted above, one or both of the Vs may come to a sharp bottom, such that the V terminates at the theoretical sharp location. In FIG. 7, the first forming recess 15FR comes to a sharp bottom, as does the second forming recess 15SR. In FIGS. 8 and 9, both forming recesses 15FR, 15SR have radiused bottoms. In FIGS. 10-14, the first forming recess 15FR comes to a sharp bottom, while the second forming recess 15SR terminates at a radiused bottom section. Variations of this nature will be apparent to skilled artisans given the present disclosure as a guide.
In certain embodiments, the die 10 has a first centerline FCL defined by an axis that is perpendicular to the first bearing base 15FBB and passes through the first theoretical sharp location FTS. Reference is made to FIG. 8. Preferably, the first locating recess 15FL is not directly aligned with the first forming recess 15FR, such that the first locating recess 15FL is spaced from the first centerline FCL. This is shown in FIG. 8.
Additionally or alternatively, the die 10 can have a second centerline SCL defined by an axis that is perpendicular to the second bearing base 15SBB and passes through the second theoretical sharp location STS. Reference is made to FIG. 9. Here again, the second locating recess 15SL preferably is not directly aligned with the second forming recess 15SR, such that the second locating recess is spaced from the second centerline SCL. This is shown in FIG. 9.
The width 810 of the first locating recess 15FL can optionally be the same (or substantially the same) as the width 800 of the second locating recess SCL. Additionally or alternatively, the two locating recesses 15FL, 15SL can optionally have the same depth. These features, though, are not strictly required.
For purposes of the present disclosure, the “first die-locating dimension” is defined as the distance between the first centerline FCL and a midpoint of the width 810 of the first locating recess 15FL. Similarly, the “second die-locating dimension” is defined as the distance between the second centerline SCL and a midpoint of the width 800 of the second locating recess 15SL. In certain embodiments, the first and second-die locating dimensions are the same or substantially the same.
In some embodiments, the die has first and second working heights that are different. The “first working height” is defined as the distance between the first bearing base 15FBB and the first workpiece-contact face 15FC. The “second working height” is defined as the distance between the second bearing base 15SBB and the second workpiece-contact face 15SC. In these embodiments, even though the first and second working heights are different, the first and second theoretical-sharp distances FTSD, STSD are the same or substantially the same. Thus, the present die is a staged, multiple forming recess (e.g., multiple-V) die.
Some embodiments involve the converging surfaces CS connected by a radiused valley section RVS, such that the first forming recess 15FR would have a greater depth if its two converging surfaces converged at constant angles over their whole length until reaching a vertex at the first theoretical sharp location FTS, rather than being connected by a radiused valley section RVS. Additionally or alternatively, the planar portions of the two convergent surfaces CS can optionally be connected by a radiused valley section RVS, such that the second forming recess SFR would have a greater depth if its two convergent surfaces converged at constant angles over their whole length until reaching a vertex at the second theoretical sharp location STS, rather than being connected by a radiused valley section. Embodiments of this nature have already been described.
In certain embodiments, the die 10 has a length, and the first 15FL and second 15SL locating recesses (e.g., channels) extend entirely along the die's length. This is best seen in FIGS. 10, 11, and 14. Additionally or alternatively, the first 15FR and second 15SR forming recesses can extend entirely along the die's length.
In FIGS. 7-14, the two locating recesses 15FL, 15SL are formed in two faces of the die that are perpendicular (or at least generally or substantially perpendicular) to each other. This, however, is not required in all embodiments.
In illustrated embodiments, the first locating recess 15FL, the second locating recess 15SL, the first forming recess 15FR, and the second forming recess 15SR all extend in directions that are parallel or substantially parallel. This is shown in FIGS. 10, 11 and 14. Here, all the locating recesses 15FL, 15SL and forming recesses 15FR, 15SR are elongated in a direction parallel or substantially parallel to the die's longitudinal axis LA.
In FIGS. 7-14, the first 15FL and second 15SL locating recesses are both rectangular channels. As noted above, the first 15FL and second 15SL locating recesses can advantageously have substantially the same width, substantially the same depth, and substantially the same length. These features, though, are not always required.
In the illustrated embodiments, die 10 has six faces: the first bearing face 15FB, the first workpiece-contact face 15FC, the second bearing face 15SB, the second workpiece-contact face 15SC, and two end faces. Reference is made to FIG. 10. In other embodiments, the die can have more faces.
Skilled artisans will appreciate that various materials can be used in manufacturing the present punches and dies. Following are a few examples of materials from which the tool bodies can be formed: (1) pre-hard tool steel, optionally with a Nitride hardened surface or the like (the Nitrided surface can have an HRC rating of up to 70); (2) pre-hard steel, optionally with laser hardened, flame hardened, or induction hardened working surfaces (optionally 28-32HRC for the pre-hard material, or 45-60 HRC for the hardened working surfaces); (3) thru-hardened tool steel, optionally with a hardness of 50-52HRC.
In certain embodiments, each punch or die is provided with a Nitrex treatment (optionally over the entire tool) for both hardness and as a rust preventative. It is to be appreciated, though, that such treatments are not strictly required.
While a preferred embodiment of the present invention has been described, it should be understood that various changes, adaptations and modifications may be made therein without departing from the spirit of the invention and the scope of the appended claims.

Claims

1. A staged quick-change multiple forming recess die for a press brake, the die having a first bearing face and a first workpiece-contact face, the first bearing face and the first workpiece-contact face being on opposed sides of the die, the first bearing face including a first bearing base and a first locating recess, the first workpiece-contact face having therein formed a first forming recess bounded by two converging surfaces, wherein two planes lying respectively on planar portions of said two converging surfaces intersect at a first theoretical sharp location, wherein a first theoretical-sharp distance is defined as the distance between the first bearing base and the first theoretical sharp location, the die having a second bearing face and a second workpiece-contact face, the second bearing face and the second workpiece-contact face being on opposed sides of the die, the second bearing face including a second bearing base and a second locating recess, the second workpiece-contact face having therein formed a second forming recess bounded by two convergent surfaces, wherein two planes lying respectively on planar portions of said two convergent surfaces intersect at a second theoretical sharp location, wherein a second theoretical-sharp distance is defined as the distance between the second bearing base and the second theoretical sharp location, the first forming recess having a first size, the second forming recess having a second size, wherein said first and second sizes are different and yet the first and second theoretical-sharp distances are substantially the same.

2. The die of claim 1 wherein the die has a first centerline defined by an axis that is perpendicular to the first bearing base and passes through the first theoretical sharp location, wherein the first locating recess is not directly aligned with the first forming recess, such that the first locating recess is spaced from the first centerline.

3. The die of claim 2 wherein the die has a second centerline defined by an axis that is perpendicular to the second bearing base and passes through the second theoretical sharp location, wherein the second locating recess is not directly aligned with the second forming recess, such that the second locating recess is spaced from the second centerline.

4. The die of claim 3 wherein the die has first and second die-locating dimensions that are substantially the same, the first locating recess having a width, the first die-locating dimension being defined as the distance between the first centerline and a midpoint of the width of the first locating recess, the second locating recess having a width, the second die-locating dimension being defined as the distance between the second centerline and a midpoint of the width of the second locating recess.

5. The die of claim 4 wherein the first locating recess is an elongated channel extending longitudinally along the die's first bearing face, and the second locating recess is an elongated channel extending longitudinally along the die's second bearing face.

6. The die of claim 1 wherein the die has first and second working heights that are different, the first working height being defined as the distance between the first bearing base and the first workpiece-contact face, the second working height being defined as the distance between the second bearing base and the second workpiece-contact face.

7. The die of claim 1 wherein the first and second workpiece-contact faces are substantially perpendicular to each other.

8. The die of claim 7 wherein the first and second bearing faces are substantially perpendicular to each other.

9. The die of claim 1 wherein the first forming recess is at least generally V-shaped.

10. The die of claim 9 wherein the second forming recess is at least generally V-shaped.

11. The die of claim 1 wherein said first size is a width of the first forming recess, said second size is a width of the second forming recess, wherein these two widths are different and yet the first and second theoretical-sharp distances are the same.

12. The die of claim 1 wherein the planar portions of said two converging surfaces are connected by a radiused valley section, such that the first forming recess would have a greater depth if its two converging surfaces converged at constant angles over their whole length until reaching a vertex at the first theoretical sharp location rather than being connected by a radiused valley section.

13. The die of claim 12 wherein the planar portions of said two convergent surfaces are connected by a radiused valley section, such that the second forming recess would have a greater depth if its two convergent surfaces converged at constant angles over their whole length until reaching a vertex at the second theoretical sharp location rather than being connected by a radiused valley section.

14. The die of claim 1 wherein the die has a length, and the first and second locating recesses extend entirely along the die's length.

15. The die of claim 14 wherein the first and second forming recesses extend entirely along the die's length.

16. The die of claim 1 wherein the first locating recess, the second locating recess, the first forming recess, and the second forming recess all extend in directions that are substantially parallel.

17. The die of claim 1 wherein the first and second locating recesses have substantially the same width, substantially the same depth, and substantially the same length.

18. The die of claim 17 wherein the first and second locating recesses are both rectangular channels.

19. The die of claim 1 wherein the die has six faces: the first bearing face, the first workpiece-contact face, the second bearing face, the second workpiece-contact face, and two end faces.

20. A staged quick-change two-V press brake die, the die having first and second bending Vs formed respectively in first and second workpiece-contact faces of the die, said first and second workpiece-contact faces being at least generally perpendicular to each other, the first bending V having a first theoretical sharp location, the second bending V having a second theoretical sharp location, the die having first and second bearing faces, the first bearing face having formed therein a first elongated locating channel, the second bearing face having formed therein a second elongated locating channel, the first bearing face being at least generally parallel to the first workpiece-contact face, the second bearing face being at least generally parallel to the second workpiece-contact face, wherein a first theoretical-sharp distance is defined as the distance between the first bearing face and the first theoretical sharp location, and a second theoretical-sharp distance is defined as the distance between the second bearing face and the second theoretical sharp location, wherein the first and second bending Vs have different widths and yet the die is configured such that the first and second theoretical-sharp distances are substantially the same.

21. A staged quick-change press brake system including a press brake with upper and lower beams, the system comprising:

a plurality of press brake tools mounted in respective tool holders on the upper beam, each tool having a tang, the tangs being received in respective tool holders,

at least one of the tools having a tip configuration different from that of another tool of said plurality,

wherein there is an upwardly facing load-bearing shoulder on only one side of the tang of each tool, each such upwardly facing shoulder contacting a downwardly facing force-transmitting surface of a tool holder, each tool having a downwardly facing tip comprising two downwardly converging surfaces, wherein two planes lying respectively on planar portions of said two converging surfaces intersect at a tool theoretical sharp location, wherein a common vertical distance separates the tool theoretical sharp location and the upwardly facing load-bearing shoulder for all the tools of said plurality, and

a plurality of press brake dies, each mounted on a rail carried by the lower beam, each die having a bearing face with a bearing base and a locating recess in which a locating ridge of the rail is received, each die having a workpiece-contact face with an upwardly open forming recess bounded by two downwardly convergent surfaces, wherein two planes lying respectively on planar portions of said two convergent surfaces intersect at a die theoretical sharp location, wherein a shared vertical distance separates the die theoretical sharp location and the bearing base for all the dies of said plurality.

22. The press brake system of claim 21 wherein the tool holders on the upper beam of the press brake have a centerline that extends vertically downwardly and passes through all of the following: (a) said downwardly facing force-transmitting surface of each tool holder, (b) said upwardly facing load-bearing shoulder of each tool, (c) the tool theoretical sharp location of each tool, and (d) the die theoretical sharp location of each die.

23. The press brake system of claim 22 wherein the locating recess of each die is not directly aligned with said centerline, such that the locating recesses of the dies are spaced from said centerline.

24. The press brake system of claim 22 wherein the locating recess in each die has a width, and the dies all have a common die locating dimension, the die locating dimension being defined as the distance between said centerline and a midpoint of said width.

25. The press brake system of claim 21 wherein the tools and dies when mated all have a common shut height, the shut height being defined as the vertical distance between the bearing base and the upwardly facing load-bearing shoulder of a mated tool and die pair.

26. The press brake system of claim 21 wherein at least one mateable tool and die pair is adapted to create a first bend, and at least one other mateable tool and die pair is adapted to create a second bend, the first and second bends being different, and wherein said tools are punches.

27. The press brake system of claim 26 wherein the first and second bends are two different bends selected from the group consisting of a 90-degree bend, a 60-degree bend, a 30-degree bend, an offset bend, and a hemming bend.

28. The press brake system of claim 27 wherein the first or second bend is a 90-degree bend.

29. The press brake system of claim 21 wherein a first mateable tool and die pair is adapted to create a first bend, a second mateable tool and die pair is adapted to create a second bend, and a third mateable tool and die pair is adapted to create a third bend, the first, second, and third bends all being different.

30. The press brake system of claim 21 wherein at least one of the dies has a working height different from that of another die of said plurality, the working height of a die being defined as the distance between its bearing base and its workpiece-contact face.

31. The press brake system of claim 30 wherein at least one of the dies has a working height at least 1/16 inch greater than that of another die of said plurality.

32. The press brake system of claim 30 wherein, on at least one of the dies, the planar portions of said two convergent surfaces are connected by a radiused valley section, such that the forming recess would have a greater depth if its two convergent surfaces converged at constant angles over their whole length until reaching a vertex at the die theoretical sharp location rather than being connected by a radiused valley section.

33. The press brake system of claim 21 wherein at least a plurality of the tools are punches with tangs each having a safety recess formed in one side.

34. The press brake system of claim 21 wherein the tool holders have seating mechanisms that, in response to clamping movements of the tool holders, move said upwardly facing shoulders of the tools into contact with the respective downwardly facing force-transmitting surfaces of the tool holders.

35. A tooling combination for a press brake having upper and lower beams, the combination comprising:

a plurality of press brake tools adapted to be mounted in respective tool holders on the upper beam, each tool having a tang, the tangs being adapted for receipt in respective tool holders,

wherein there is a load-bearing shoulder on only one side of the tang of each tool, each such shoulder being adapted to contact a downwardly facing force-transmitting surface of a tool holder when the tools are operatively mounted in respective tool holders, each tool having a tip comprising two converging surfaces, wherein two planes lying respectively on planar portions of said two converging surfaces intersect at a tool theoretical sharp location, wherein a common distance separates the tool theoretical sharp location and the load-bearing shoulder for all the tools of said plurality, and

a plurality of press brake dies, each adapted to be mounted on a rail carried by the lower beam, each die having a bearing face with a bearing base and a locating recess adapted to receive a locating ridge of the rail, each die having a workpiece-contact face with a forming recess bounded by two convergent surfaces, wherein two planes lying respectively on planar portions of said two convergent surfaces intersect at a die theoretical sharp location, wherein a shared distance separates the die theoretical sharp location and the bearing base for all the dies of said plurality.

36. The combination of claim 35 wherein the tools and dies when mated all have a common shut height, the shut height being defined as the distance between the bearing base and the load-bearing shoulder of a mated tool and die pair.

37. The combination of claim 35 wherein at least one of the dies has a working height different from that of another die of said plurality, the working height of a die being defined as the distance between its bearing base and its workpiece-contact face.

38. The combination of claim 37 wherein at least one of the dies has a working height at least 1/16 inch greater than that of another die of said plurality.

39. The combination of claim 35 wherein, on at least one of the dies, the planar portions of said two convergent surfaces are connected by a radiused valley section, such that the forming recess would have a greater depth if its two convergent surfaces converged at constant angles over their whole length until reaching a vertex at the die theoretical sharp location rather than being connected by a radiused valley section.

40. The combination of claim 35 wherein at least one mateable tool and die pair is adapted to create a first bend, and at least one other mateable tool and die pair is adapted to create a second bend, the first and second bends being different, and wherein said tools are punches.

41. The combination of claim 40 wherein the first and second bends are two different bends selected from the group consisting of a 90-degree bend, a 60-degree bend, a 30-degree bend, an offset bend, and a hemming bend.

42. The combination of claim 35 wherein a first mateable tool and die pair is adapted to create a first bend, a second mateable tool and die pair is adapted to create a second bend, and a third mateable tool and die pair is adapted to create a third bend, the first, second, and third bends all being different.

43. The combination of claim 35 wherein at least a selected one of the tools includes a seating mechanism, the seating mechanism being adapted to seat the load-bearing shoulder of the selected tool against a downwardly facing force-transmitting surface of a selected tool holder in response to a clamping movement of the selected tool holder.

44. The combination of claim 35 further including the press brake, wherein each of a plurality of the tool holders comprises a pivotable clamp.

45. A fabrication method involving a press brake with upper and lower beams, the method comprising:

providing a plurality of press brake tools, each tool having a tang, at least one of the tools having a tip configuration different from that of another tool of said plurality, wherein there is a load-bearing shoulder on only one side of the tang of each tool, each tool having a tip comprising two converging surfaces, wherein two planes lying respectively on planar portions of said two converging surfaces intersect at a tool theoretical sharp location, wherein a common distance separates the tool theoretical sharp location and the load-bearing shoulder for all the tools of said plurality,

providing a plurality of press brake dies, each die having a bearing face with a bearing base and a locating recess, each die having a workpiece-contact face with a forming recess bounded by two convergent surfaces, wherein two planes lying respectively on planar portions of said two convergent surfaces intersect at a die theoretical sharp location, wherein a shared distance separates the die theoretical sharp location and the bearing base for all the dies of said plurality,

providing an arrangement of tools and dies on the press brake by: (i) mounting the tools in respective tool holders of the upper beam such that the load-bearing shoulders of the tools confront downwardly facing force-transmitting surfaces of respective tool holders, and (ii) mounting each die on a rail carried by the lower beam such that the locating recess of each die receives a locating ridge of the rail,

positioning a workpiece between a first mateable tool and die pair and then forming a first bend in the workpiece by bringing the upper and lower beams of the press brake together so as to deform the workpiece between the tool and die of the first mateable pair, and without changing the arrangement of tools and dies on the press brake, positioning the workpiece between a second mateable tool and die pair and then forming a second bend in the workpiece by bringing the upper and lower beams of the press brake together so as to bend the workpiece between the tool and die of the second mateable pair, wherein the first and second bends are two different types of bends.

46. The method of claim 45 wherein the tool holders on the upper beam have a centerline that extends vertically downwardly and passes through all of the following: (a) said downwardly facing force-transmitting surface of each tool holder, (b) said load-bearing shoulder of each mounted tool, (c) the tool theoretical sharp location of each mounted tool, and (d) the die theoretical sharp location of each mounted die.

47. The method of claim 46 wherein the locating recess of each mounted die is not directly aligned with said centerline, such that the locating recesses of the mounted dies are spaced from said centerline.

48. The method of claim 46 wherein the locating recess of each die has a width, and the mounted dies all have a common die locating dimension, the die locating dimension being defined as the distance between said centerline and a midpoint of said width.

49. The method of claim 45 wherein the tools and dies when mated all have a common shut height, the shut height being defined as the distance between the bearing base and the load-bearing shoulder of a mated tool and die pair.

50. The method of claim 45 wherein the first and second bends are two different bends selected from the group consisting of a 90-degree bend, a 60-degree bend, a 30-degree bend, an offset bend, and a hemming bend.

51. The method of claim 50 wherein the first or second bend is a 90-degree bend.

52. The method of claim 45 wherein the method further comprises using a third mateable tool and die pair to make a third bend in the workpiece, the first, second, and third bends all being different types of bends.