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Title:
SYSTEM AND METHOD FOR TWISTING HOLLOW BARS
Document Type and Number:
WIPO Patent Application WO/2016/148640
Kind Code:
A1
Abstract:
A system and method for twisting a hollow bar having one end supported and fixed using a supporting device and the other end attached to one end of a connector; the other end of the connector being connected to a twisting device; the twisting device having at least one pivoted point engaging the connector to enable a twist force applied to the other end of the hollow bar.

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Inventors:
HENG KIAN YONG (SG)
Application Number:
PCT/SG2015/000084
Publication Date:
September 22, 2016
Filing Date:
March 19, 2015
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
HENG KIAN YONG (SG)
International Classes:
B21D11/00; B21D11/14
Foreign References:
US5771726A1998-06-30
US6189359B12001-02-20
US4437329A1984-03-20
ES2163947B12003-03-01
Attorney, Agent or Firm:
NG, Kim Tean (P.O. BOX 1861Robinson Road Post Office, Singapore 1, SG)
Download PDF:
Claims:
CLAIMS

What is claimed is:

1. A system for twisting at least one hollow bar, comprising:

at least one supporting device for supporting and fixing one end of the hollow bar;

at least one connector, wherein one end of the connector is engaged with the other end of the hollow bar; and

at least one twisting device configured to rotate at a predetermined speed for providing a torque to the hollow bar, wherein the twisting device has at least one shaft having at least one pivoted point to which the other end of the connector is mechanically connected such that the twist force applied to the other end of the hollow bar alters the muscle memories of the hollow bar without distorting a physical structure and a cross sectional shape of the hollow bar.

2. The system of claim 1 , wherein the supporting device has at least one supporting portion comprising a lower support bracket and an upper support bracket, the supporting portion configured for supporting one end of the hollow bar.

3. The system of claim 2, wherein the supporting device has one or more fixing elements for firmly fixing the one end of the hollow bar when inserted into the supporting portion.

4. The system of claim 1 , wherein the supporting portion has an opening which is shaped to hold a specified hollow bar.

5. The system of claim 1 , wherein the shaft is connected to at least one motor.

6. The system of claim 1 , wherein the twisting device functions to twist the hollow bar so that the hollow bar retains a twist shape after being twisted beyond the elasticity limit of the hollow bar.

7. The system of claim 1 , wherein the twist force is applied to the connector.

8. The system of claim 1 , wherein the connector is an external connector comprising a pivoting bracket, the external connector configured to enclose an end of the hollow bar.

9. The system of claim 8, wherein the other end of the hollow bar is slotted into the pivoting bracket.

10. The system of claim 1 , wherein the connector is an internal connector configured for insertion into the hollow bar, the internal connector comprising a pivoting bracket and a guide bar.

11. The system of claim 10, wherein the pivoting bracket is configured for insertion into the hollow bar and the guide bar is configured for insertion into the pivoting bracket.

12. A method for twisting a hollow bar, comprising:

fixing one end of the hollow bar in at least one supporting device;

connecting the other end of the hollow bar to one end of at least one connector;

inserting other end of the connector to at least one pivoting point in a shaft of at least one twisting device, wherein the shaft is connected to a motor;

rotating the twisting device at a predetermined speed so as to produce a first twisting force in a first direction to over twist the hollow bar; and providing a second twisting force in a second direction, opposite to the first direction so as to produce a required twist of the hollow bar.

13. The system of claim 12, wherein the step of connecting the other end of the hollow bar comprises the step of inserting the connector into the hollow bar.

14. The system of claim 13, wherein the outside surface of the connector generally conforms to the inside surface of the hollow bar.

15. The system of claim 12, wherein the step of connecting the other end of the hollow bar comprises the step of enclosing the other end of the hollow bar in the connector.

16. The system of claim 15, wherein the outside surface of the connector conforms to the inside surface of the hollow bar.

17. A method for producing a twist in a hollow bar, the method comprising the steps of:

over twisting the hollow bar in a first direction so as to change muscle memories of the hollow bar; and

twisting the hollow bar in a direction opposite to first direction so as to achieve a predetermined degree of twist in the hollow bar without requiring supports to retain the predetermined degree of twist.

Description:
SYSTEM AND METHOD FOR TWISTING HOLLOW BARS

TECHNICAL FIELD

[0001] The present disclosure relates generally to hollow metal bars used in architectural industry. Embodiments of the disclosure are related to a system and method for twisting hollow metal bars by altering the material muscle memor of the hollow metal bars without distorting its physical structure and cross sectional shape.

BACKGROUND

[0002] In an architectural industry, a row of bars forms a grille, grating, divider, railing, and other metalwork pieces, openwork cover or barrier to doors and windows, louvre, lattice forms, sun shades, screens and the like. In particular, each of the bars may be purposely deformed, or so formed, into certain twisted pattern along its longitudinal axis resulting in a twisted or helical spiral for aesthetics or ornamentation.

[0003] International patent application, WO 2010096018 discloses amethod for fabricating a hollow bar that forms elements of a grille or railing of a metalwork piece where the bar is twisted into a spiral form for decorative or ornamental purposes either manually or by utilizing machine-assisted or automated machinery. The hollow bar comprises separate longitudinal parts that are hinge joined to complementarily fasten each other to form the hollow bar. The longitudinal joints are amenable to increased torsional stress, such that each of the parts may be twisted without breaching the material's fatigue limit and the bar as a whole capable of being twisted with more spiral turns within its elasticity limits. The twisted bar may thus be released for re-working for adjustments or re-installation. A number of exemplary joint, internal and external bracing accessories are also disclosed to cater for the different longitudinal part fabrication, for example, by extrusion or roll-milling.

[0004] The hollow bars of different size and shape require different twisting torque. In smaller hollow bars, the twisting can be performed manually with the help of simple hand tools, as it requires less twisting torque. Due to the stiffness of the metal, the bigger hollow bars require higher torque compared to the smaller hollow bars. Hence, it would be difficult to twist bigger hollow bars manually. Further, the hollow bars are capable of regaining its original shape after being twisted, as its muscle memories are not changed during twisting process and hence needs to be fixed using bracing accessories.

[0005] A need, therefore, exists for a machine-assisted or automated machinery apparatus and method for twisting the bigger hollow metal bars that overcomes the above drawbacks.

SUMMARY

[0006] The following summary is provided to facilitate an understanding of some of the innovative features unique to the disclosed embodiment and is not intended to be a full description. A full appreciation of the various aspects of the embodiments disclosed herein can be gained by taking into consideration the entire specification, claims, drawings, and abstract as a whole.

[0007] It is, therefore, one aim of the disclosed embodiments to provide for a system for twisting a hollow bar comprising a supporting device for supporting and fixing one end of the hollow bar, at least one connector and a twisting device. One end of the connectoris connected to other end of the hollow bar before being connected to the twisting device. The twisting device is configured to rotate at a predetermined speed for providing a twist force to the hollow bar. The twisting device has at least one shaft having at least one pivoting point into which the other end of the connector is connected such that the twist force applied to the other end of the hollow bar alters the muscle memories of the hollow bar without distorting the physical structure and cross sectional shape of the hollow bar.

[0008] It is, therefore, one aim of the disclosed embodiments to provide for a system wherein the supporting device has at least one supporting portion comprising a lower support bracket and an upper support bracket into which the one end of the hollow bar is inserted for support.

[0009] It is, therefore, one aim of the disclosed embodiments to provide for a system wherein the supporting device has one or more fixing elements for firmly fixing the one end of the hollow bar when inserted into the supporting portion.

[0010] It is, therefore, one aim of the disclosed embodiments to provide for a system wherein the supporting portion has a shape that is capable of holding the hollow bar of varying widths.

[0011] It is, therefore, one aim of the disclosed embodiments to provide for a system wherein the shaft of the twisting device is connected to at least one motor.

[0012] It is, therefore, one aim of the disclosed embodiments to provide for a system wherein the twisting force is applied to the connector and not directly to the hollow bar.

[0013] It is, therefore, one aim of the disclosed embodiments to provide for a system wherein the connector is an external connector comprising a pivoting bracket. The other end of the hollow bar is slotted into the pivoting bracket.

[0014] It is, therefore, one aim of the disclosed embodiments to provide for a system wherein connector is an internal connector comprising a pivoting bracket and a guide bar. The pivoting bracket and the guide bar are inserted into the other end of the hollow bar.

[0015] It is, therefore, one aim of the disclosed embodiments to provide for a method for twisting at least one hollow bar comprising fixing one end of the hollow bar in a supporting device, connecting other end of the hollow bar to one end of a connector, inserting other end of the connector to at least one pivoting point in a shaft of a twisting device and allowing the twisting device to rotate at a predetermined speed. The shaft of the twisting device is connected to a motor. The twisting force is provided in a first direction to over twist the hollow bar and then provided in a direction to opposite to the first direction to obtain required twist of the hollow bar.

[0016] It is, therefore, one aim of the disclosed embodiments to provide for a method for twisting at least one hollow bar of bigger cross section in which over twisting the hollow bar alters its muscle memories.

[0017] It is, therefore, one aim of the disclosed embodiments to provide for a method for twisting at least one hollow bar comprising over twisting the hollow bar in a first direction, changing muscle memories of the hollow bar, twisting the hollow bar in a direction opposite to the first direction and achieving predetermined degree of twist without using supports to retain the twist.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The summary above, as well as the following detailed description of illustrative embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, exemplary constructions of the disclosure are shown in the drawings. However, the disclosure is not limited to specific methods and instrumentalities disclosed herein. Moreover, those in the art will understand that the, drawings are not to scale. Wherever possible, like elements have been indicated by identical numbers.

[0019] FIG. 1 is an illustration of a perspective view of a supporting device having a supporting portion utilized for supporting one end of a hollow metal bar during a twisting process, wherein the position of the supporting device is aligned with an axis of rotation of the hollow metal bar, in accordance with the disclosed embodiments;

[0020] FIG. 2 is an illustration of a perspective view of hollow bars of various cross sectional shapes, in accordance with the disclosed embodiments;

[0021] FIG; 3 is an illustration of a perspective view of the supporting device depicted in FIG. 1 holding one end of a hollow bar depicted in FIG. 2, in accordance with the disclosed embodiments;

[0022] FIG. 4 is an illustration of an perspective view of another supporting device having two supporting portions for holding two hollow bars depicted in FIG. 2 of different cross sectional shapes, in accordance with the disclosed embodiments;

[0023] FIG. 5 is an illustration of a perspective view of a twisting device utilized to hold and twist an end of one of the twisted hollow metal bars during the twisting process, in accordance with the disclosed embodiments;

[0024] FIG. 6 is an illustration of an exploded view showing an internal mounting method of securing the hollow bars to the twisting device in which a guide bar and a pivoting bracket are inserted into to the hollow metal bar, in accordance with the disclosed embodiments;

[0025] FIG. 7 is an illustration of an exploded view showing an external mounting method of securing the hollow bar to the twisting device in which the hollow bar is slotted to the pivoting bracket, in accordance with the disclosed embodiments;

[0026] FIG. 8 is an illustration of a perspective view of the twisting device depicted in FIG. 3 utilized for twisting the two hollow bars that are secured in the supporting device depicted in FIG. 4 during the twisting process, in accordance with the disclosed embodiments;

[0027] FIG. 9A-9C illustrate a perspective view of the hollow bar twisted at various stages of the twisting process, in accordance with the disclosed embodiments;

[0028] FIGS. 10A-10C illustrates of a perspective view of the hollow bar depicted in FIG. 7 at various stages of the twisting process, in accordance with the disclosed . embodiments; and

[0029] FIG. 11 is an illustration of a flow chart pertaining to a method of twisting the hollow bar using the system depicted in FIG. 7, in accordance with the disclosed embodiments.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0030] The particular configurations discussed in the following description are non- limiting examples that can be varied and are cited merely to illustrate at least one embodiment and are not intended to limit the scope thereof,

[0031] Referring to FIG. 1 , a supporting device 100 for supporting and fixing one end of the hollow metal bar (not shown) is disclosed. The supporting device 100 utilized for holding/anchoring the hollow bar is only for illustration purpose and other similar devices that can hold/anchor the hollow bar can also be used without limitation. The supporting device 100 has a pair of vertically raised legs 102 and 104 to position a supporting portion 107 above the ground 114.

[0032] A horizontal bar 105 fits over the vertically raised legs 102 and 104. The supporting portion 107 is placed on the horizontal bar 105. The supporting portion

107 comprises an upper support bracket 106 and a lower support bracket 108. The lower support bracket 108 is fixed to the horizontal bar 105, and the upper support bracket 106 is movable to enable insertion of a hollow bar (not shown) into the supporting portion 107. The upper support bracket 106 and lower support bracket

108 are bolted, or otherwise clamped together by mechanical means, so that they can be separated and the metal hollow bar can easily be retrieved after twisting.

[0033] For example, the upper support bracket 106 can be easily moved up so that the hollow bar can be inserted into the supporting portion 107 and then the upper support bracket 106 can be lowered down to fit in the supporting portion 107. The supporting portion 107 comprises an opening 109 substantially approximating the shape of the cross-section of the hollow bar, and the dimensions of the opening 109 approximate the cross-sectional dimensions of the hollow bar. The hollow bar is thus firmly fixed between the lower support bracket 108 and upper support bracket 106 by means of fixing elements 110 and 112 which allows the hollow bar to be firmly fixed after fitting the hollow bar in the supporting portion 107. The fixing elements 110 and 112 can be bolts, for example, or any clamping device to hold hollow bars in position while a twisting force is being applied to the hollow bar.

[0034] FIG. 2 is an illustration of a perspective view of hollow bars 300-305 of various possible cross sections, in accordance with the disclosed embodiments. The supporting portion 107 of the supporting device 100 depicted in FIG. 1 can hold, and keep from being turned, any one end of the hollow bars 300-305. The hollow bars 300-305 can be of various cross sectional shapes such as square, triangle, oval, rectangle, round, etc., and other cross sections are also applicable without limitation depending on the aesthetics or ornamentation requirement.

[0035] An end of any one of the hollow bars 300-305 is first inserted and positioned in the opening 109 of the supporting portion 107. The fixing elements 110 and 112 may be tightened as required. After the end of the hollow bar 300, 301 , 302, 303, 304, or 305 has been secured, the remaining length of the hollow bar 300, 301 , 302, 303, 304, or 305 is "over twisted" in one direction, that is, twisted beyond the elasticity limit of the hollow bar material. The hollow bar is then twisted in the opposite direction, and released when a specified degree of twist has been reached in the opposite angular direction. It is to be noted that different hollow bars have different thresholds of twisting for "point of return", wherein the hollow bar is permanently deformed.. There is no certain angle to define "over twist". It is observed that point of "over twisting" is very near to "point of destruction". This retains the permanent twist of the hollow bar, even after twisting is no longer being applied. Accordingly, the disclosed method does not require the use of end supports or internal stiffener rods that are used to retain the twist, as disclosed in the International patent application: WO 2010096018.

[0036] FIG. 3 is an exemplary illustration of a perspective view of the supporting device 100 depicted in FIG. 1 holding one end of the hollow bar 300 depicted in FIG. 2, in accordance with the disclosed embodiments. The hollow bar 300 is inserted into the opening 109 of the supporting portion 107 of the supporting device 100. The fixing elements 110, 112 are initially loosened such that the upper support bracket 106 can be positioned to hold one end of the hollow bar 300 that is inserted into the supporting portion 107. After inserting the hollow bar 300 inside the supporting portion 107, the upper support bracket 106 is placed back over the lower support bracket 107 and thefixing elements 110 and 112 are tightened to fix the hollow bar 300 firmly in the supporting device 100.

[0037] FIG. 4 is an illustration of a perspective view of an exemplary embodiment of a supporting device 120 having the supporting portion107 and a second supporting portion 101 for holding two hollow bars 300 and 301 of different cross sections respectively, in accordance with the disclosed embodiments. The free ends of the hollow bars 300 and 301 may be connected to the shafts of a twisting machine (not shown), according to an exemplary embodiment, to show that the two supporting portions 101 and 107 can include openings (not shown) of different shapes conforming to the external cross-sectional shape of a hollow rod that is to be retained in the supporting device 120. For example, the supporting portion 101 can include an opening of rectangular shape to hold the hollow bar 301 having a rectangular cross section, and the supporting portion 107 can include the opening 109 which is oval shape to hold the hollow bar 300 having an oval cross section.

[0038] FIG. 5 is an illustration of a perspective view of a twisting device 200 utilized to hold and twist one or two selected hollow bars during a twisting process, in accordance with the disclosed embodiments. The twisting device 200 has one or more rotating shafts 206 and 208 that are connected to a motor (not shown) housed inside the twisting device 200. In an exemplary embodiment, the shafts 206 and 208 may both operate simultaneously, at a selected rotational speed or torque, and preferably rotating in the same direction. The device 200 has plurality of pivoting points for releasably attaching one of the rotating shafts 206, 208 to the free end of a respective hollow bar. For example, in the embodiment shown, the shaft 208 has pivoting points 201 and 203, and the shaft 206 has a pivoting point 204. The selected hollow bar can be mechanically connected to the respective rotating shaft in various possible ways known and assumed by a person skilled in art, such as an external mounting method or an internal mounting method.

[0039] FIG. 6 is an illustration of an exploded isometric view showing an internal mounting method in which a guide bar 400 is sized and shaped for insertion into a hole 212 in the pivoted point 204, and in which a pivoting bracket 402 is sized and shaped for insertion into the hollow bar 300, in accordance with the disclosed embodiments. It can be appreciated by one skilled in the art that (i) placement of the pivoting bracket 402 into the opening of the hollow bar 300, and (ii) engagement with the guide bar 400 enables substantially all the torque produced by the twisting machine 200 (shown in FIG. 8) to be used in twisting the hollow bar 300. This method produces a twisted configuration of the hollow bar 300 without damage to the end of the hollow bar 300, as might result from a conventional method of grasping the end of the hollow bar 300.

[0040] As shown in the illustration, the guide bar 400 has an outside configuration that enables a user to place the guide bar 400 into the hole 212 in the pivoted point 204. The guide bar 400 has a non-circular cross section that prevents the guide bar 400 from rotating with respect to the pivoted point 204 after the guide bar 400 is placed into the hole 212. In a preferred embodiment, the outside surface of the guide bar 400 is precisely the same size and shape as is the inside surface of the hole 212 and the inside surface of the hole 214. In the configuration shown, the guide bar 400 and the hole 212 have substantially congruent rectangular (or square) cross-sectional shapes, but it should be understood that any non-circular cross- sectional shape can be used.

[0041] The shaft 206 uses the linked combination of the pivoted point 204, the guide bar 400, and a hole 214 in the pivoting bracket 402to mechanically engage the hollow bar 300 such that, when the shaft 206 rotates and produces a torque, the mechanical engagement forces the free end of the hollow bar 300 to rotate, or twist, as well. The combination of the guide bar 400 and the pivoting bracket 402 form a connector which mechanically connects the free end of the hollow bar 300 to the pivot point 204. As can be appreciated by one skilled in the art, the outside surface of the connector, that is, the outside surface of the pivoting bracket 402, conforms to the inside surface of the hollow bar 300.

[0042] An alternate external mounting method is shown in FIG. 7. The shaft 208 has two pivoted points 201 and 203 for holding a free end of a selected hollow bar, such as the hollow bar 301 in the illustration. The hollow bar 301 is slotted into a pivoted bracket 401, which is slotted into the pivoted points 201 and 203. The pivoted bracket 401 includes a first guide tab 406 for engagement with a first hole 216 in the pivoted point 201 , and a second guide tab 408 for engagement with a second hole 218 in the pivoted point 203. The guide tabs 406, 408 are shown as having square cross-sectional shapes for respective insertion into the holes 216, 218, but any cross-sectional shape can be used, including circular cross sections.

[0043] The pivoted bracket 401 also includes a rectangular opening 404 sized and shaped to removably enclose th free end of the hollow bar 301 such that the hollow bar 301 is prevented from rotating with respect to the pivoted bracket 401 when the hollow bar 301 is inserted into the pivoted bracket 401. It can be appreciated by one skilled in the art that placement of the pivoting bracket 401 into the openings 216 and 218 of the shaft 208 and enclosure of the hollow bar 300 with the pivoting bracket 401 enables substantially all the torque produced by the twisting machine 200 (shown in FIG. 8) to be used in twisting the hollow bar 301. This method produces a twisted configuration of the hollow bar 301 without damage to or distortion of the end of the hollow bar 301 , as might result from a conventional method of grasping the end of the hollow bar 301. The pivoted bracket 401 serves as a connector for mechanically connecting the hollow bar 301 to the pivoted point 201 and the pivoted point 203. As can further be appreciated by one skilled in the art, the inside surface of the connector, that is, the inside surface of the rectangular opening 404, conforms to the outside surface of the hollow bar 301.

[0044] As can be appreciated by one skilled in the art, twisting a larger hollow bar requires a higher torque than twisting a smaller hollow bar. Accordingly, the twisting device 200 is preferably configured with a motor of sufficient power to provide such higher torque. Further, the twisting device 200 is also configured to rotate in both clockwise and counterclockwise directions at a constant predetermined speed. For example, the twisting device 200 may initially rotate the free end of the hollow bar at a predetermined speed or torque in one direction, such that the hollow bar is over twisted to change its metal memories. By changing the metal memories, a required twist upto a certain degree, of the hollow bar can be achieved without need for supports to maintain the twisted configuration of the hollow bar. Then, the twisting device 200 rotates the free end of the hollow bar in the opposite direction until the required permanent twist is achieved.

[0045] Referring again to FIG. 6, the small rigid hollow guide bar 400 and pivoted bracket 402 may be utilized to removably connect the free end of the hollow bar 300 to the pivoted point 204 of the twisting machine 200. One end of the guide bar 400 is fixed to other end of the hollow bar 300 via the pivoted bracket 402 while the other end of the guide bar 400 is fixed to the pivoted point 204 of the twisting device 200. The guide bar 400 preferably has a cross section similar to that of the pivoted point 204 and the pivoting bracket 402 such that the guide bar 400 can be easily inserted into the pivoted point 204 and the pivoting bracket 240. It should be noted that the hollow bar 300 can be formed by joining two or more longitudinal parts of similar cross section. The cross sectional shape and size of the guide bar 400, the inner surface of the hollow bar 300, and the size and shape of the hole 214 in the pivoted point 204 are selected such that the guide bar 400 can be firmly inserted into the hollow bar 300 and the pivoted point 204. In this configuration, the twisting force provided by the twisting machine 200 is not directly applied to the hollow bar 300, but is instead applied through the guide bar 400. This retains the cross section and physical shape of the hollow bar 300 even when the hollow bar 300 is over twisted to change its muscle memories.

[0046] The dual pivoting points 201 and 203 as shown in FIG. 7 can also be utilized with two pivoting brackets 402, depicted in FIG. 6 for twisting operations on hollow bars (not shown) having larger internal openings than the internal opening of hollow bar 300, to better capture the desired twisted shape without distorting the physical structure and the cross sectional shape of the hollow bar.

[0047] Internal pivoting brackets 402 depicted in FIG. 6 can be inserted into the pivoting point 204 using the guide bar 400, and the external pivoting bracket 401 depicted in FIG. 7 can be slotted into the pivoting points 201 and 203, in a non- permanent connections. Once the respective twisting operation is done, the respective pivoting brackets 401 , 402 and the guide bar 400 can easily be retrieved. [0048] As shown in FIG. 8, the figure illustrates different mounting methods and configuration. Different shapes of the bars require different torque for twisting. According to the system 450 as shown in FIG. 8, more than one hollow bar can be twisted in the same operation. The hollow bars 300 and 301 are supported between the supporting device 100 and the twisting device 200. The hollow bars 300 and 301 are rotated at a predetermined speed and torque in one direction (e.g., clockwise) using the twisting device 200. It should be noted that one end of the hollow bars 300 and 301 are fixed/anchored at the supporting device 100 and the free ends are rotated at the twisting device 200. The hollow bars 300 and 301 are twisted many times such that the respective muscle memories are changed. FIG. 9A shows an angle of hollow bar 300 with respect to an axis of rotation of rotating shaft, beginning at zero degrees.

[0049] As shown in FIG. 9B, the angle of axis of hollow bar 300 with respect to axis of rotation shaft is initially over twisted, say at 450°, in one direction (clockwise) to change its muscle memories. Then, as depicted in FIG. 9C, the over twisted hollow bar 300 is twisted in other direction (anti-clockwise), say 225° until the required twist of the hollow bar 300 is obtained. As the metal memories of the hollow bars 300 are changed, then the required twist of the hollow bar 300 is obtained, the twist of the hollow bar 300 is retained and the need for conventional end supports or internal stiffener rods to retain the twist configuration of the hollow bar 300 can be avoided.

[0050] It should be noted that any degree of twisting lesser than, as depicted in FIG. 9B, say lesser than 225° without the need for the supports to retain the lesser twist can still be achieved by further rotating at the opposite direction (i.e., anticlockwise). Further, any degree greater than as depicted in FIG. 9B, say greater than 225° will require supports to retain the greater twist. The over twisting and releasing angles of hollow bars depends upon their size, length, thickness and shape.

[0051] It also should be noted that the parameters such as duration, speed, rotation degree and torque required for twisting the hollow bars depends on the length, size and shape of the hollow bars. The direction, speed, duration and torque required to over twist the hollow bar are different from the direction, speed, duration and torque required to twist the over twisted hollow bars to obtain final twisted hollow bars.

[0052] Initially the untwisted shape of the hollow bar, say the hollow bar 300, is similar to the untwisted shape shown in FIG. 2. Then, the hollow bar 300 is twisted in one direction as shown in FIG. 10A, to produce an initial twisted configuration, and then over twisted as shown in FIG. 10B, to produce a subsequent twisted configuration without distorting the physical structure and the cross sectional shape of the hollow bar 300. The twist of the hollow bar 300 shown in FIGS. 10A-10B is in one direction. The over twisted of the hollow bar 300 shown in FIG. 10B will have the muscle memories changed compared to the original hollow bar 300 depicted in FIG. 2. The over twisted hollow bar 300 is then twisted in the opposite direction until the required twist is obtained. FIG. 10C shows the final twisted hollow bar 300 that can be used for aesthetics or ornamentation purposes, without need for the conventional internal and/or external bracing accessories to retain the twist.

[0053] FIG. 11 is an illustration of a flow chart 500 pertaining to a method of twisting a hollow bar, such as the hollow bar 300 of FIG. 2, using the system 450 depicted in FIG. 8, in accordance with the disclosed embodiments. At step 502, one end of the hollow bar is supported and fixed using the supporting device 100 depicted in FIG. 1.

[0054] At step 504, the other end of the hollow bar is releasably engaged with the twisting device 200. The hollow bar can be connected to the twisting device 200 by using internal or external pivoting brackets 401, 402 as depicted in FIGS. 6-7. The twisting device 200 rotates the hollow bar in one direction such that the hollow bar is over twisted, at step 506. At steps 508 and 510, the over twisted hollow bar is twisted in a direction opposite to the first direction until a required twist of the hollow bar is achieved.

[0055] Finally the hollow bar is removed from the supporting and twisting device 100, and used for aesthetic purposesat step512. It should be noted that the twisted hollow bar does not require supports to retain the twist after twisting process. The physical structure and cross sectional shape of the final twisted bar is not changed after twisting process. After over twisting the hollow bar beyond the elasticity limit of the hollow bar, the metal will spring back by itself to an opposite direction, due to the elasticity of the material, but will not return to the original position.

[0056] It will be appreciated that variations of the above disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Also, various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.

[0057] Although embodiments of the current disclosure have been described comprehensively in considerable detail to cover the possible aspects, those skilled in the.art would recognize that other versions of the disclosure are also possible.