Method And Apparatus For Forming Profiled Articles

Abstract

An apparatus (40) for forming a profiled article (46) comprises: a forming path (41) through which a blank of deformable material to be formed into the profiled article passes; a pair of complementary and opposing body forming die members (45, 45′) adapted to travel along the forming path (41); and a drive (44, 44′) that facilitates travel of the body forming die members (45, 45′) along the forming path (41), wherein the pair of body forming die members (45, 45′) is adapted to act on the blank of deformable material independently to form a desired profile on the blank. Locating elements (75) that locate the blanks may be provided. A method of forming material is also provided. Further, there is provided a length of deformable material for use with the apparatus.

Description

FIELD OF INVENTION

The present invention relates to a method and apparatus for forming profiled articles, the profiled articles being generally irregular in their body profile. In particular, the invention relates to a method and apparatus in which at least one body forming die block is employed to form at least part of the profiled article. The invention is thought to provide an alternative to current stamping techniques.

BACKGROUND ART

Known systems for forming deformable materials such as sheet metal into a desired profile, particularly a desired uniform profile, include roll forming processes. These processes involve passing the sheet metal through a sequence of roll sets, each further deforming the sheet beyond the profile achieved at the previous roll set. The disadvantages of roll forming include redundant deformation resulting from non-uniform strain paths as the strip passes each roll set. This in turn leads to high residual stresses which result in product defects such as edge wave, flare, twist, and so on. Another disadvantage of roll forming is that the distance between the first roll set and the last roll set is relatively large. Consequently, the space needed to house a roll forming assembly is substantial, particularly when forming complex profiles.

Known systems using multiple roll sets also suffer from significant difficulties associated with initial alignment. A further disadvantage of roll forming is that tooling design is related to the designer's experience. “Trial and error” plays a dominant role in tooling design and alignment and for a new complex profile tooling design, this means the development time is less predictable. Additionally a large amount of material can be wasted during the period of tooling design and alignment, which contributes to the cost of tooling development.

In more recent times, chain-die forming has been proposed as an alternative in the production of articles having uniform profiles. Chain-die forming may be considered an extension of roll forming that involves forming the product gradually through at least one pass through a plurality of relatively short die blocks that incrementally form a blank into a final uniform profiled article. That is, as the blank moves through each die pair its cross-sectional profile is changed until the final desired cross-sectional profile is achieved. The roll radii used in chain-die forming are very large and, therefore, the longitudinal strain imparted to the material being formed is generally very small or negligible. As such, chain-die formed articles may have only a small amount of residual stress resulting from the forming process.

The formation of articles having irregular profiles requires other considerations. Conventionally, such articles are produced by stamping. Stamping, which is also known as pressing, generally includes a variety of sheet-metal forming manufacturing processes. For example, this may include punching using a machine press or stamping press, blanking, embossing, bending, flanging, and coining. Stamping may involve a single stage operation where every stroke of the press produces the desired form on the sheet metal part, or may alternatively involve a series of stages. The process is usually carried out on sheet metal, but can also be used on other materials, such as polystyrene.

Articles produced by stamping generally have earring that needs to be trimmed off after the stamping process, resulting in wasted material and additional processing time. Stamping is also discontinuous and requires a blank-holder to hold the blank in place during processing.

The present invention aims to provide an alternative to the aforementioned forming techniques, for the production of articles which may be irregular in profile.

The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one exemplary technology area where some embodiments described herein may be practice.

SUMMARY OF INVENTION

The present invention relates to a method and apparatus for forming profiled articles, the profiled articles being generally irregular in their body profile. In particular, the invention relates to a method and apparatus in which at least one body forming die block is employed to form at least part of the profiled article.

One aspect of the present invention provides an apparatus for forming a profiled article comprising:

• • a forming path through which a blank of deformable material to be formed into the profiled article passes;
  • a pair of complementary and opposing body forming die members adapted to travel along the forming path; and
  • a drive that facilitates travel of the body forming die members along the forming path,
  • wherein the pair of body forming die members is adapted to act on the blank of deformable material independently to form a desired profile on the blank.

The apparatus may comprise any number of pairs of body forming die members, or a single pair of body forming die members. In one embodiment, the apparatus comprises a plurality of pairs of body forming die members, each pair of body forming die members being adapted to act on a respective blank of deformable material independently to form a desired profile on each respective blank. According to this embodiment neighbouring body forming die members of the plurality of pairs of body forming die members are generally hingedly connected to one another. Preferably, neighbouring body forming die members are hingedly connected with minimal clearance therebetween. This ensures a relatively strong structure and a simplified structure compared with, for example, chain-die forming.

In preferred embodiments, the apparatus comprises locating elements mounted between adjacent body forming die members, the locating elements being adapted to locate the blanks prior to engagement of the blanks with the body forming die members. In that regard, adjacent blanks may be connected to one another with a web and the locating elements may be disposed between adjacent body forming die members on a lower section of the forming path and, in use, locate on one or both sides of respective webs. Preferably, an upper section of the forming path comprises gaps between adjacent body forming die members, the gaps cooperating with and receiving respective locating elements in use.

The locating elements may be of any suitable form, provided they serve to substantially restrict movement of the blanks relative to the die members when the locating elements are engaged with the blanks. For example, the locating elements may comprise blocks, cylinders, hooks, bolts or pins. In a preferred embodiment, the locating elements comprise pins.

In certain embodiments, the pair of body forming die members, or each of the pair of body forming die members, is adapted to form the blank of deformable material into the profiled article in a single pass along the forming path. Depending on the complexity of the profile, two or more passes may be required.

In other embodiments, the pair of body forming die members, or each of the pair of body forming die members, is adapted to form the blank of deformable material into a profiled intermediate in a single pass along the forming path, the apparatus comprising at least one additional pair of body forming die members adapted to independently act on the profiled intermediate in at least one additional pass along the forming path, or along an additional forming path of the apparatus, to form the profiled article. If the forming path is that used in the initial forming process, the additional pair of body forming die members is inserted into the forming path, thereby replacing the initial pair of body forming die members. Generally, though, the apparatus will comprise at least one additional forming path along which a respective pair of the at least one additional pair of body forming die members travels.

Generally, although not essentially, the pair of body forming die members, or each of the pair of body forming die members, is of a length substantially equivalent to that of the blank of deformable material and acts along the length of the blank. That is, the body forming die members effectively “stamp” the length of the blank with the desired profile. In particular, a forming surface of the die member with which the blank comes into contact may be configured with at least a portion of the desired profile.

The apparatus preferably comprises first and second mounts that define the forming path therebetween and which mount first and second body forming die members of the pair of body forming die members. The first and second mounts may comprise drive cogs that engage the first and second body forming die members and that are driven by the drive.

In certain embodiments, the first and second mounts define first and second endless paths along which a first set of first body forming die members and a second set of second body forming die members respectively travel.

In other embodiments, the first and second mounts define a limited path along which the pair of body forming die members travel in forward, forming, motion and reverse, resetting, motion.

The form of the first and second mounts is not particularly limited. For example, at least one of the first and second mounts may comprise a large radial surface through the forming path. Each of the first and second mounts may comprise a large radius surface through the forming path. The respective radii of the large radius surfaces may be substantially equal, or are different. The curvature centres of radii may be on respective opposite sides of the forming path, or may be on the same side of the forming path. One of the first and second mounts may comprise a large radius surface through the forming path and the other of the first and second mounts may comprise a substantially flat surface through the forming path.

The blanks for deformable material may be of any suitable dimensions, dictated by the article to be formed. Generally, it is envisaged that the apparatus will primarily be suitable for use on blanks having a length of from about 100 mm to 3,000 mm, although the invention is not bound to these dimensions.

According to another aspect of the invention there is provided a method of forming a profiled article comprising:

• • passing a blank of deformable material to be formed into the profiled article through a forming path comprising a pair of complementary and opposing body forming die members adapted to travel along the forming path; and
  • progressively engaging the blank with the pair of complementary and opposing body forming die members;
  • wherein the pair of body forming die members is adapted to act on the blank of deformable material independently to form a desired profile on the blank.

As will be appreciated by the above discussion, the forming path may comprise a plurality of pairs of body forming die members, in which case the method preferably comprises passing a plurality of blanks of deformable material through the forming path and engaging a respective blank with a respective pair of body forming die members to independently to form a desired profile on each respective blank. In this embodiment, the method preferably comprises locating the blanks prior to engagement of the blanks with the body forming die members, the locating being achieved with locating elements mounted between adjacent body forming die members. Again, the locating elements preferably comprise locating pins, although the above option and others may also be appropriate.

In certain embodiments, the pair of body forming die members forms the blank of deformable material into the profiled article in a single pass along the forming path.

In other embodiments, the pair of body forming die members forms the blank of deformable material into a profiled intermediate in a single pass along the forming path, the method further comprising:

• • passing the profiled intermediate through at least one additional forming path comprising a respective at least one additional pair of complementary and opposing body forming die members adapted to travel along the a respective at least one additional forming path; and
  • progressively engaging the profiled intermediate with the at least one additional pair of body forming die members,
  • wherein the at least one additional pair of body forming die members independently acts on the profiled intermediate in at least one additional pass along the at least one additional forming path to form the profiled article.

Again, in certain embodiments the pair of body forming die members is of a length substantially equivalent to that of the blank of deformable material and acts along the length of the blank. Likewise, blanks having a length of from about 100 mm to 3,000 mm will be suitable for use in the method, although the invention is not bound to these dimensions.

According to another aspect of the invention there is provided a length of deformable material for use with an apparatus as described above, specifically an apparatus that comprises locating elements mounted between adjacent body forming die members, the locating elements being adapted to locate the blanks prior to engagement of the blanks with the body forming die members. The length of material of this aspect of the invention comprises a plurality of blanks of the deformable material, wherein consecutive blanks of the length of deformable material are connected to one another by a web of material, the web and the consecutive blanks defining recesses adapted to engage the locating elements of the apparatus.

In certain embodiments the blanks and webs may be formed from the same material or different materials and may be connected or joined together by ay suitable means. Preferably, though, the blanks and the webs are integral with one another.

The length of deformable material may take the form of a sheet or strip, or may take any other form. In certain embodiments, the length of deformable material is in the form of a roll that can be fed to the forming path of the apparatus.

Preferably, the blanks have a length of from about 100 mm to 3,000 mm, although the invention is not bound to these dimensions.

In a further aspect of the invention there is provided a profiled article formed using the apparatus or method of the invention.

The present invention consists of features and a combination of parts hereinafter fully described and illustrated in the accompanying drawings, it being understood that various changes in the details may be made without departing from the scope of the invention or sacrificing any of the advantages of the present invention.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS

To further clarify various embodiments of the present invention, a more detailed description of the invention follows with reference to specific embodiments thereof, which are illustrated in the accompanying drawings. It should be appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting on its scope. The invention will be described and explained with additional specificity and detail through the accompanying drawings in which:

FIG. 1 illustrates the method of an embodiment of the invention in which a number of body forming die blocks are used to form an irregular profiled article.

FIG. 2 illustrates a blank used in the method illustrated in FIG. 1.

FIG. 3 illustrates the profiled article produced by the method illustrated in FIG. 1.

FIG. 4 illustrates an apparatus according to an embodiment of the invention including a number of body forming die blocks.

FIG. 5 illustrates a pair of irregular body forming die blocks.

FIG. 6 illustrates an alternative arrangement for an apparatus and method of an embodiment of the invention.

FIGS. 7 and 8 illustrate an embodiment of the apparatus of the invention showing locating pins for locating a run of blanks.

FIGS. 9a-9c illustrate drive arrangements for the apparatus of embodiments of the invention.

FIGS. 10a-10c illustrate profiles for forming surfaces of apparatuses according to embodiments of the invention, along which body forming die blocks travel.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention relates to a method and apparatus for forming profiled articles, the profiled articles being generally irregular in their body profile. In particular, the invention relates to a method and apparatus in which at least one body forming die block is employed to form at least part of the profiled article.

Hereinafter, this specification will describe the present invention according to the preferred embodiments. It is to be understood that the following description of the preferred embodiments of the invention is provided to facilitate discussion of the present invention and it is envisioned that without departing from the scope of the appended claims.

Referring to FIG. 1, a simplified diagram of a forming method 10 from a blank 11 (as shown in FIG. 2) to a final product 12 (shown in FIG. 3) is illustrated. In the illustrated method 10, the blank 11 experiences ‘n’ forming passes through body forming die block pairs 13 to gradually achieve the final product 12. The proposed method 10 differs to conventional stamping, which can form the final product in a single stroke, as the proposed method 10 involved rolling of the blank 11 between the die block pairs 13. This does not require a blank-holder, as is the case with stamping, and does not result in the need to trim off earring. Importantly, each of the die block pairs 13 imparts a desired profile to the blank 11. Each die block pair 13 acts on the blank 11 to facilitate production of a final product 12 having an irregular profile. To compare with chain-die forming, the proposed method 10 employs whole body forming die blocks 13 instead of discrete die-blocks seen in chain-die forming. It is considered that the use of whole body forming die blocks 13 in the proposed method 10 advantageously ensures that the forming dies have higher strengths than those used in chain-die forming and are free of gaps between the dies. As such, it is envisaged that the surface finish of the final product 12 will be improved. Also, from the mechanical implementation stand point, the structure of the apparatus, discussed below, is simpler and much more robust compared with chain-die forming.

Referring to FIG. 4, an apparatus 40 according to an embodiment of the invention is illustrated. The apparatus 40 includes a forming path 41 disposed between a first mount 42 and a second mount 43. Additional mounts may be provided, although this will not be described here in any detail. The first and second mounts 42, 43 include drive gears 44, 44′ that engage cooperating first die members 45 and second die members 45′ respectively. According to this embodiment, the first and second mounts 42, 43 may form endless paths (e.g. these may be large radii elliptical mounts) or large radii semi-elliptical mounts. Blanks of deformable material travel along the forming path 41 between the cooperating first and second die members 45, 45′ to form final products 46.

Each pair of cooperating first and second die members 45, 45′ acts on a respective blank to impart the characteristics of the pairs of die members 45, 45′ to the blank. Put another way, each pair of die members 45, 45′ acts as a whole body die block that acts on the length of a respective blank independent of any subsequent processing with further die pairs. Therefore, the pairs of die members 45, 45′ do not act in a similar way to die pairs in chain-die forming, in which a length of deformable material is sequentially deformed to a desired cross-sectional profile. Rather, the pairs of die members 45, 45′ effectively act in a similar way to a conventional stamping mechanism. As illustrated, the profiles of the pairs of die members 45, 45′ act independently on a respective blank to form this into the desired profile of the final product 46, which may be generally irregular or may be uniform.

There is very little gap 47 between consecutive pairs of die members 45, 45′, which are hingedly connected by joints 48. This ensures that the die members 45, 45′ are of relatively high strength compared with, for example, conventional chain-die blocks used in the forming of generally uniform profiles. The arrangement also prevents or ameliorates issues relating to earring generally associated with stamping processes. It is envisaged that the arrangement will also result in better quality finishes in the final product 46.

Examples of the die members 45, 45′ are provided in FIG. 5. Referring to this figure, the first die member 45 includes a first profile 55 and the second die member 45′ includes a second profile 55′. The first and second profiles 55, 55′ are complementary and impart a desired profile to the final product as the blank or intermediate passes between the pair of die members 45, 45′.

In an alternative embodiment of the apparatus 60, as illustrated in FIG. 6, the pair of die members 45, 45′ draws a blank 61 into the apparatus 60 and moves the blank 61 forward 62 to facilitate forming. Once the process is complete, the final product 63 is produced and the apparatus 60 reverses and moves the die members 45, 45′ backwards 64 and returns to the start position.

A preferred embodiment of the apparatus of the invention is illustrated in FIGS. 7 and 8. Referring to these figures, the apparatus 70 is substantially as described above in that a blank 71 of deformable material is passed between sets of die members 45, 45′ to form a final product 73. However, in this embodiment the apparatus 70 includes locating pins 75 on one side or on opposing sides of the die members 45, 45′, generally located in lower gaps between the die members 45, 45′ and in cooperation with upper gaps 77 between the die members 45, 45′. The locating pins 75 engage recesses 76 between blanks 71, the blanks 71 in this embodiment being joined by webs 78. This advantageously ensures that the blanks 71 are correctly positioned between respective die members 45, 45′ as they pass through the apparatus 70. Hence, die members 45, 45′ act independently on a respective blank 71 passing through the apparatus 70.

FIGS. 9a to 9c show some exemplary ways in which the apparatus 90 can operate. In FIG. 9a the system is provided with driving gears 91 which drive the two sets of die elements 45, 45′ in phase so as to draw a section through the forming portion. In FIG. 9b a separate set of driving rolls 92 is provided to propel this section through the forming portion. FIG. 9c shows a similar configuration in which a separate set of driving rolls 93 are used to push a section through the forming portion.

FIGS. 10a to 10c show some of the possible configurations of the forming path in the forming portion of the apparatus. In FIG. 10a each of the opposed forming portions has a large radius and the centres of the radii are respectively on the opposite sides of the forming space. FIG. 10b shows a configuration in which one of the forming portions has a large radius and another has an infinite radius or in other words is flat. FIG. 10c shows a configuration in which the centres of the radii are both on one side of the forming space and large radii are used for the respective forming portions to provide converging paths between the opposed dies. It is also considered that a configuration may be provided in which the radii of the forming portion are not constant, for example to provide a converging track between the opposed dies.

Unless the context requires otherwise or specifically stated to the contrary, integers, steps or elements of the invention recited herein as singular integers, steps or elements clearly encompass both singular and plural forms of the recited integers, steps or elements.

Throughout this specification, unless the context requires otherwise, the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated step or element or integer or group of steps or elements or integers, but not the exclusion of any other step or element or integer or group of steps, elements or integers. Thus, in the context of this specification, the term “comprising” is used in an inclusive sense and thus should be understood as meaning “including principally, but not necessarily solely”.

It will be appreciated that the foregoing description has been given by way of illustrative example of the invention and that all such modifications and variations thereto as would be apparent to persons of skill in the art are deemed to fall within the broad scope and ambit of the invention as herein set forth.

Claims

1. An apparatus for forming a profiled article comprising: a forming path through which a blank of deformable material to be formed into said profiled article passes;a pair of complementary and opposing body forming die members adapted to travel along said forming path; anda drive that facilitates travel of said body forming die members along said forming path,wherein said pair of body forming die members is adapted to act on said blank of deformable material independently to form a desired profile on said blank.

2. An apparatus according to claim 1, comprising a plurality of pairs of body forming die members, each pair of body forming die members being adapted to act on a respective blank of deformable material independently to form a desired profile on each respective blank.

3. An apparatus according to claim 2, wherein neighbouring body forming die members of said plurality of pairs of body forming die members are hingedly connected to one another.

4. An apparatus according to claim 3, wherein said neighbouring body forming die members are hingedly connected with minimal clearance therebetween.

5. An apparatus according to any one of claims 2 to 4, comprising locating elements mounted between adjacent body forming die members, said locating elements being adapted to locate said blanks prior to engagement of said blanks with said body forming die members.

6. An apparatus according to claim 5, wherein said locating elements comprise locating pins.

7. An apparatus according to claim 5 or 6, wherein adjacent blanks are connected to one another with a web and wherein said locating elements are disposed between adjacent body forming die members on a lower section of said forming path and, in use, locate on one or both sides of respective webs.

8. A apparatus according to claim 7, wherein an upper section of said forming path comprises gaps between adjacent body forming die members, said gaps cooperating with and receiving respective locating elements in use.

9. An apparatus according to any one of the preceding claims, wherein said pair of body forming die members, or each of said pair of body forming die members, is adapted to form said blank of deformable material into said profiled article in a single pass along said forming path.

10. An apparatus according to any one of the preceding claims, wherein said pair of body forming die members, or each of said pair of body forming die members, is adapted to form said blank of deformable material into a profiled intermediate in a single pass along said forming path, said apparatus comprising at least one additional pair of body forming die members adapted to independently act on said profiled intermediate in at least one additional pass along said forming path, or along an additional forming path of said apparatus, to form said profiled article.

11. An apparatus according to claim 10, wherein said apparatus comprises at least one additional forming path along which a respective pair of said at least one additional pair of body forming die members travels.

12. An apparatus according to any one of the preceding claims, wherein said pair of body forming die members, or each of said pair of body forming die members, is of a length substantially equivalent to that of said blank of deformable material and acts along the length of said blank.

13. An apparatus according to any one of the preceding claims, comprising first and second mounts that define said forming path therebetween and which mount first and second body forming die members of said pair of body forming die members.

14. An apparatus according to claim 13, wherein said first and second mounts comprise drive cogs that engage said first and second body forming die members and which are driven by said drive.

15. An apparatus according to claim 13 or 14, wherein said first and second mounts define first and second endless paths along which a first set of first body forming die members and a second set of second body forming die members respectively travel.

16. An apparatus according to claim 13 or 14, wherein said first and second mounts define a limited path along which said pair of body forming die members travel in forward, forming, motion and reverse, resetting, motion.

17. An apparatus according to any one of claims 13 to 16, wherein at least one of the first and second mounts comprises a large radius surface through said forming path.

18. An apparatus according to claim 17, wherein each of the first and second mounts comprises a large radius surface through said forming path.

19. An apparatus according to claim 18, wherein the respective radii of the large radius surfaces are substantially equal, or are different.

20. An apparatus according to claim 18 or 19, wherein the curvature centres of radii are on respective opposite sides of said forming path, or are on the same side of the forming path.

21. An apparatus according to claim 17, wherein one of the first and second mounts comprises a large radius surface through said forming path and the other of said first and second mounts comprises a substantially flat surface through said forming path.

22. A method of forming a profiled article comprising: passing a blank of deformable material to be formed into said profiled article through a forming path comprising a pair of complementary and opposing body forming die members adapted to travel along said forming path; andprogressively engaging said blank with said pair of complementary and opposing body forming die members;wherein said pair of body forming die members is adapted to act on said blank of deformable material independently to form a desired profile on said blank.

23. A method according to claim 22, wherein said forming path comprises a plurality of pairs of body forming die members, and wherein said method comprises passing a plurality of blanks of deformable material through said forming path and engaging a respective blank with a respective pair of body forming die members to independently to form a desired profile on each respective blank.

24. A method according to claim 23, comprising locating said blanks prior to engagement of said blanks with said body forming die members, said locating being achieved with locating elements mounted between adjacent body forming die members.

25. A method according to claim 24, wherein said locating elements comprise locating pins.

26. A method according to any one of claims 22 to 25, wherein said pair of body forming die members forms said blank of deformable material into said profiled article in a single pass along said forming path.

27. A method according to any one of claims 22 to 25, wherein said pair of body forming die members forms said blank of deformable material into a profiled intermediate in a single pass along said forming path, said method further comprising: passing said profiled intermediate through at least one additional forming path comprising a respective at least one additional pair of complementary and opposing body forming die members adapted to travel along said a respective at least one additional forming path; andprogressively engaging said profiled intermediate with said at least one additional pair of body forming die members,wherein said at least one additional pair of body forming die members independently acts on said profiled intermediate in at least one additional pass along said at least one additional forming path to form said profiled article.

28. A method according to any one of claims 22 to 27, wherein said pair of body forming die members is of a length substantially equivalent to that of said blank of deformable material and acts along the length of said blank.

29. A length of deformable material for use with an apparatus as claimed in any one of claims 5 to 8, comprising a plurality of blanks of said deformable material, wherein consecutive blanks of said length of deformable material are connected to one another by a web of material, said web and said consecutive blanks defining recesses adapted to engage the locating elements of the apparatus.

30. A length of deformable material according to claim 29, wherein said blanks and said webs are integral with one another.

31. A length of deformable material according to claim 29 or 30, wherein said length of deformable material is in the form of a roll that can be fed to the forming path of the apparatus.

32. A profiled article formed in an apparatus of any one of claims 1 to 21, or formed by a method of any one of claims 22 to 28.