Abstract:
A roll forming apparatus including a plurality of stations each including and an upper roll and a lower roller, wherein a first number of stations are configured to form a pipe blank into a standing seam, and a second number of stations are configured to angle the seam. At least one station includes elongated top and bottom rollers for clinching the pipe blank during the roll forming process. Each elongated top roller is mounted on a pivotable shaft configured to pivot the elongated top rollers away the pipe blank to allow passage of at least one seam formed in the pipe blank.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a United States national stage of International Application No. PCT/US2014/030411, filed Mar. 17, 2014, which published as International Pubilcation No. WO 2014/145616, and which claims the benefit under 35 U.S.C. §119(e) of the earlier filing date of U.S. Provisional Patent Application No. 61/792,512 filed on Mar. 15, 2013, which is hereby incorporated by reference. 
     
    
     FIELD OF INVENTION 
       [0002]    This application is generally directed to the field of roll formers. 
       BACKGROUND 
       [0003]    Products used in heating/ventilation/air conditioning (HVAC) units are typically formed of sheet stock such as sheet metal. Examples of metals include steel, aluminum and the like. In particular, pipe or duct work for HVAC units is typically made from one or more sections of sheet stock that are formed to create a conduit. In general, duct work or conduit may have a round and/or rectangular cross section. The sections of steel conduit are joined to create the duct work. Seams are created along each pipe section where the sheet stock is joined resulting in steel against steel joint. Roll formers are typically used to form sheet metal into ducts. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]    Various embodiments of the invention are described herein by way of example in conjunction with the following figures, wherein like reference characters designate the same or similar elements. 
           [0005]      FIG. 1  is a schematic view of a portion of a duct system. 
           [0006]      FIG. 2  is a cross-sectional view taken along line  2 - 2  of  FIG. 1 . 
           [0007]      FIG. 3  is a cross-sectional view taken along line  3 - 3  of  FIG. 1 . 
           [0008]      FIG. 4  is a cross-sectional view taken along line  4 - 4  of  FIG. 1 . 
           [0009]      FIG. 5  is an isometric projection of a pipe of  FIG. 1 . 
           [0010]      FIG. 6A  is a cross-sectional view taken along line  6 - 6  of  FIG. 5 . 
           [0011]      FIG. 6B  is a cross-sectional view taken along line  6 - 6  of  FIG. 5  in a locked conformation in accordance with the embodiment of  FIG. 6A . 
           [0012]      FIG. 7A  is a cross-sectional view taken along line  6 - 6  of FIG. 
           [0013]      FIG. 7B  is a cross-sectional view taken along line  6 - 6  of  FIG. 5  in a locked conformation in accordance with the embodiment of  FIG. 7B . 
           [0014]      FIG. 8  is a cross-sectional view taken along line  4 - 4  of  FIG. 1  in a locked conformation. 
           [0015]      FIG. 9  is a flow diagram of a method of fabricating the pipe and fitting coupling system of  FIG. 1 . 
           [0016]      FIG. 10  shows a perspective view of embodiments of a roll forming. 
           [0017]      FIG. 11  shows stations  1 - 10  of the embodiment of  FIG. 10  with top elongated rolls removed. 
           [0018]      FIG. 12  shows stations  1 - 10  of the embodiment of  FIG. 10  showing the pivoting roller arrangement. 
           [0019]      FIG. 13  shows the pivoting roller arrangement in a pivoted up position. 
           [0020]      FIG. 14  shows how the pipe ducts is bent at stations  1 - 9  of  FIG. 10 . 
           [0021]      FIGS. 15A-15C  show end and two side views of the top roll of station  1  of  FIG. 10 . 
           [0022]      FIGS. 16A-16C  show end and two side views of the bottom roll of station  1  of  FIG. 10 . 
           [0023]      FIGS. 17A-17C  show end and two side views of the top roll of station  2  of  FIG. 10 . 
           [0024]      FIGS. 18A-18C  show end and two side views of the bottom front roll of station  2  of  FIG. 10 . 
           [0025]      FIGS. 19A-19C  show end and two side views of the bottom rear roll of station  2  of  FIG. 10 . 
           [0026]      FIGS. 20A-20C  show end and two side views of the top roll of station  3  of  FIG. 10 . 
           [0027]      FIGS. 21A-21C  show end and two side views of the bottom front roll of station  3  of  FIG. 10 . 
           [0028]      FIGS. 22A-22C  show end and two side views of the bottom rear roll of station  3  of  FIG. 10 . 
           [0029]      FIGS. 23A-23C  show end and two side views of the top roll of station  4  of  FIG. 10 . 
           [0030]      FIGS. 24A-24C  show end and two side views of the bottom front roll of station  4  of  FIG. 10 . 
           [0031]      FIGS. 25A-25C  show end and two side views of the bottom rear roll of station  4  of  FIG. 10 . 
           [0032]      FIGS. 26A-26C  show end and two side views of the top roll of station  5  of  FIG. 10 . 
           [0033]      FIGS. 27A-27C  show end and two side views of the bottom front roll of station  5  of  FIG. 10 . 
           [0034]      FIGS. 28A-28C  show end and two side views of the bottom rear roll of station  5  of  FIG. 10 . 
           [0035]      FIGS. 29A-29C  show end and two side views of the top roll of station  6  of  FIG. 10 . 
           [0036]      FIGS. 30A-30C  show end and two side views of the bottom front roll of station  6  of  FIG. 10 . 
           [0037]      FIGS. 31A-31C  show end and two side views of the bottom rear roll of station  6  of  FIG. 10 . 
           [0038]      FIGS. 32A-32C  show end and two side views of the top roll of station  7  of  FIG. 10 . 
           [0039]      FIGS. 33A-33C  show end and two side views of the bottom front roll of station  7  of  FIG. 10 . 
           [0040]      FIGS. 34A-34C  show end and two side views of the bottom rear roll of station  7  of  FIG. 10 . 
           [0041]      FIGS. 35A-35C  show end and two side views of the top roll of station  8  of  FIG. 10 . 
           [0042]      FIGS. 36A-36C  show end and two side views of the bottom front roll of station  8  of  FIG. 10 . 
           [0043]      FIGS. 37A-37C  show end and two side views of the bottom rear roll of station  8  of  FIG. 10 . 
           [0044]      FIGS. 38A-38C  show end and two side views of the top roll of station  9  of  FIG. 10 . 
           [0045]      FIGS. 39A-39C  show end and two side views of the bottom front roll of station  9  of  FIG. 10 . 
           [0046]      FIGS. 40A-40C  show end and two side views of the bottom rear roll of station  9  of  FIG. 10 . 
           [0047]      FIGS. 41A-41C  show end and two side views of the bottom rear roll of station  9  of  FIG. 10 . 
           [0048]      FIGS. 42A-42C  show end and two side views of the bottom rear roll of station  9  of  FIG. 10 . 
       
    
    
     DETAILED DESCRIPTION 
       [0049]    In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings and that some embodiments are described by way of reference only. The invention is capable of embodiments in addition to those described and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. 
         [0050]    The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. The roll former according to embodiments of the invention can be used in the formation of ducts, for example, such as the ducts illustrated in FIGS. 1-9 and disclosed in U.S. patent application Ser. No. 14/020,611, filed Sep. 6, 2013, the disclosure of which is incorporated by reference. As shown in  FIG. 1 , a pipe and fitting coupling system  10  includes a first pipe  12 , a second pipe  14 , and a joint  16 . In addition to the straight pipes shown, the pipe and fitting coupling system  10  may include any suitable pipe and/or fitting known to those skilled in the art. Examples of suitable pipes and fittings include round and rectangular pipes, small and large radius elbow joints, ‘Y’ joints, ‘T’ joints, registers, and the like. Thus, for the sake of brevity, the term, “pipe  12 ” and “pipe  14 ” are used throughout the present disclosure and the figures depict a round pipe, however the embodiments are not limited to round pipes, but rather, the terms, “pipe  12 ” and “pipe  14 ” refer to round and rectangular pipe and fittings for the same. 
         [0051]    To continue, the first pipe  12  has a pipe diameter D and a plain end  18 . The second pipe has a receiving end  20 . The receiving end is a single piece of shaped sheet metal. In general, the metal may include any suitable metal. Examples of suitable metals include steel, aluminum, alloys, and the like. In addition, the pipes  12  and/or  14  and receiving end  20  may be made of any other suitable material. Examples of suitable materials include malleable, injectable, and/or moldable materials such as, for example, plastics and other polymers, resins, and the like. 
         [0052]    As shown in  FIG. 2 , the receiving end  20  includes a first axial flange  22 , a second axial flange  24 , an axial groove  26 , and a sealant  28 . In general, the axial flanges  22  and  24  facilitate positioning the plain end  18  in the axial groove  26 . The sealant  28  includes any suitable elastomeric, resilient, or otherwise malleable material that is capable of forming and maintaining a seal with the plain end  18 . Particular examples of suitable materials include butyl rubber and the like. The first axial flange  22  has a first flange diameter D 1  that is greater than the pipe diameter D. The second axial flange  24  has a second flange diameter D 2  that is less than the pipe diameter D. The second axial flange  24  extends further axially than the first axial flange  22 . As described herein, this axial extension of the second axial flange  22  facilitates securing the plain end  18  of the first pipe  12  in the receiving end  20  of the second pipe  14 . 
         [0053]    The axial groove  26  is disposed at the pipe diameter and between the first axial flange  22  and the second axial flange  24 . To facilitate telescoping the plain end  18  into the receiving end, the first axial flange  22  has an inwardly angled face  30  to meet the axial groove  26  and the second axial flange  24  has an outwardly angled face  32  to meet the axial groove  26 . These angled faces  30  and  32  simplify the task of aligning the two ends  18  and  20  and initiating the telescoping of the plain end  18  towards the axial groove  26 . The sealant  28  is disposed in the axial groove  26  to seal the plain end  18  in the receiving end  20 . The joint  16  is formed by the cooperative alignment of the plain end  18  being inserted into the receiving end  20  and being sealed by the sealant  28 . 
         [0054]    Also shown in  FIGS. 1 and 2  is a fastener  34 . As shown in  FIG. 2 , the fastener  34  is configured to pierce a wall of the plain end  18  and a wall of the second axial flange  24 . In this manner, the plain end  18  may be secured in the receiving end  20 . In general, the fastener  34  includes any suitable fastener. Examples of suitable fasteners include screws, pop-rivets, and the like. In a particular example, the fastener  34  is a self-tapping metal screw. 
         [0055]      FIG. 3  is a cross-sectional view taken along line  3 - 3  of  FIG. 1 . As shown in  FIG. 3 , the second axial flange  24  includes a series of crimps  36  disposed about the circumference of the second axial flange  24 . The series of crimps  36  are configured to provide a taper in the second axial flange  24 . As such, the second axial flange is formed into a portion of a cone, e.g., a frusta-conical segment to facilitate telescopically sliding the plain end  18  over the second axial flange  24  and into the axial groove  26 . In various embodiments, the size or width of each crimp of the series of crimps  36  is about 2 mm to about 15 mm. More particularly, each crimp is about 4 mm wide. 
         [0056]      FIG. 4  is a cross-sectional view taken along line  4 - 4  of  FIG. 1 . As shown in  FIG. 4 , the inwardly angled face  30  of the first axial flange  22  includes an angle A 1 . In general, the angle A 1  includes any suitable angle. More particularly, the angle A 1  is about 1° to about 15° to facilitate telescopically sliding the plain end  18  into the axial groove  26 . More particularly still, the angle A 1  is about 10°. The outwardly angled face  32  of the second axial flange  24  includes an angle A 2 . In general, the angle A 2  includes any suitable angle. More particularly, the angle A 2  is about 1° to about 15° to facilitate telescopically sliding the plain end  18  into the axial groove  26 . More particularly still, the angle A 2  is about 5°. 
         [0057]    Also shown in  FIG. 4 , the first axial flange  22  extends a length L 1  past a bottom or proximal portion of the axial groove  26 . The length L 1  includes any suitable length. In general, the length L 1  may vary from about ¼ inch (0.6 cm) to about ½ inch (1.3 cm). The second axial flange  24  extend a length L 2  past a distal end of the first axial flange  22 . In general, the length L 2  is to provide sufficient area to secure the fastener  34 . Depending upon the type of fastener utilized, the length L 2  may vary from about 1 cm to about 5 cm. In a particular example, the length L 2  is about 2.54 cm. 
         [0058]      FIG. 5  is an isometric projection of the pipe  12  of  FIG. 1 . As shown in  FIG. 5 , the pipe  12  includes a longitudinal lock  50 . The longitudinal lock  50  includes a male portion  52  and female portion  54 . Also shown in  FIG. 5  is an intersection zone  56  where the receiving end  20  (e.g., the transverse seal) intersects with the longitudinal lock  50 . It is at this intersection zone  56  that the pipe and fitting coupling system  10  has the greatest tendency to leak. In order to offset this leakage tendency, additional sealant, such as the sealant  28 , may be utilized as described herein. 
         [0059]      FIG. 6A  is a cross-sectional view taken along line  6 - 6  of  FIG. 5  in accordance with an embodiment of the invention. As shown in  FIG. 6A , the male portion  52  includes a hem  60  and the female portion  54  includes a locking groove  62 . As shown in  FIG. 6B , in response to the male portion  52  being inserted sufficiently into the female portion  54 , the hem  60  slides past the locking groove  62  and engages the locking groove  62  to secure the male portion  52  in the female portion  54 . 
         [0060]      FIG. 7A  is a cross-sectional view taken along line  6 - 6  of  FIG. 5  in accordance with another embodiment of the invention. As shown in  FIG. 7A , the male portion  52  includes the hem  60  and the female portion  54  includes the locking groove  62 . Alternatively, the longitudinal lock  50  may include a button lock. In addition, the female portion  54  includes a sealant  64  disposed in a channel  66 . As shown in  FIG. 7B , in response to the male portion  52  being inserted sufficiently into the female portion  54 , the male portion  52  is pressed against the sealant  64  to form a seal and the hem  60  slides past the locking groove  62  and engages the locking groove  62  to secure the male portion  52  in the female portion  54 . 
         [0061]      FIG. 8  is a cross-sectional view taken along line  4 - 4  of  FIG. 1  in a locked conformation in accordance with another embodiment of the invention. As shown in  FIG. 8 , the pipe and fitting coupling system  10  optionally includes a sealant  80  in a groove corresponding to the back side of the first axial flange  22 . If included, the sealant  80  is configured to reduce or eliminate air leakage at the intersection zone  56 . That is, by placing in the groove corresponding to the back side of the first axial flange  22 , air leakage at the intersection zone  56  has been reduced based upon empirical testing. 
         [0062]    Also shown in  FIG. 8 , the pipe and fitting coupling system  10  optionally includes a lock  82  disposed at the joint  16  configured to secure the plain end  18  in the receiving end  20 . In general, the lock  82  includes any suitable locking structure(s) such as tabs, barbs, hems, locking grooves, buttons, dimples, hooks, catches, detents, and the like. In a particular example, the plain end  18  includes a hem  84  and the receiving end  20  includes a locking groove  86 . In various examples, the hem  84  and locking groove  86  may be configured to releasably engage or substantially non-releasably engage (that is, the engagement may be sufficiently secure such that uncoupling the joint  16  results in a permanent deformation of at least the hem  84  and locking groove  86 ). In yet another example, the plain end  18  includes a series of the hems  84  or buttons, dimples, and the like spaced about the circumference and the receiving end includes a series of locking grooves or catches spaced about the circumference. In this manner, the lock  82  may be selectively engaged by rotating the plain end  18  relative to the receiving end  20 . 
         [0063]      FIG. 9  is a flow diagram of a method  90  of fabricating the pipe and fitting coupling system of  FIG. 1 . In general, to fabricate a pipe such as the pipe  12  and  14 , a supply of sheet metal is uncoiled with an uncoiler at step  92 . The sheet metal is then flattened with a flattener to reduce the coil set, e.g., the tendency of the metal to coil at step  94 . At step  96 , the sheet metal is measured and cut to the predetermined dimensions by a shear, for example. A notcher removes segments of sheet metal that would otherwise interfere with the longitudinal or transverse locking mechanism at step  98 . The notched sheet now travels to a conventional longitudinal lock former via a transfer table. At step  100 , the sheet now receives the longitudinal lock  50  such as a “snap” lock shown in  FIGS. 6A and 7A  or “button” lock mechanism as shown in  FIGS. 6B and 7B . One side is roll formed to a female lock, the other side to a male lock. While the locks are being formed, a sealant is injected into the female portion on the lock at step  102 . Upon exiting the lock former, the pipe blank travels onto another transfer table that changes the direction of travel by 90 degrees at step  104 . At step  106 , the pipe blank enters the inventive roll former configured to form the receiving end  20 . 
         [0064]    In general, structures such as flanges and grooves are formed in sheet stock by passing the stock through a series of rolls or dies. A first roll in the series may initiate a bend and subsequent rolls accentuate the structure. In order to fabricate the receiving end  20 , the receiving end  20  is ‘flared’ or otherwise formed with a die and/or rolls to generate an outwardly angled face  38 . In general, the outwardly angled face  38  increases the diameter of the pipe from the diameter D to the diameter D 1 . Once the outwardly angled face  38  is formed, the first axial flange  22 , the axial groove  26  and second axial flange  24  are formed by passing the receiving end  20  through one or a series of rolls or dies. Following step  106 , the sealant  28  is injected or otherwise disposed in the axial groove  26  at step  108 . The blank then travels to a crimper machine and the series of crimps  36  may be formed in the second axial flange  24  at step  110 . Following fabrication, the completed pipe  12  exits onto a run-out table where it is inspected and then packaged at step  112 . 
         [0065]    Alternatively, the pipe and fitting coupling system may be fabricated via a molding or casting process. For example, as is generally known, a negative mold of the pipe  12  may be generated and a material may be introduced to the mold to form the pipe  12 . 
         [0066]    Embodiments of a roll forming machine  300  used to form the receiving end  20  of pipe  12  are illustrated in  FIGS. 10-42C . The roll forming machine  300  preferably has nine stations or more stations for forming the receiving end  20  on the pipe blank. In the illustrated embodiment, there are nine stations  1 - 9  ( 301  to  309 ). Each of stations  1 - 9  have a top roll and a bottom roll which both move the pipe blank forward while at the same time bending the pipe blank to form the receiving end  20  of pipe  12  as described above. Stations  1  ( 301 ) to 6 ( 306 ) form the pipe blank into a standing seam, stations  8  ( 308 ) and 9 ( 309 ) angle the seam to a specific angle depending on the gauge of the material so it will bend to form a pocket when rolled in a later process. The illustrated embodiment further includes a tenth station  10  ( 310 ). The top and bottom rollers at station  10  do not bend the pipe blank and serve to convey the pipe blank out of the roll former. The bend of the pipe blank at each station is shown in  FIG. 14 .  FIGS. 15A to 42C  show the top and bottom (front and rear) rolls of stations  1  to  9 . As discussed above, a sealant injection nozzles  312 ,  314  are located between stations  5  ( 305 ) and 6 ( 306 ) and after station  9  ( 309 ) to inject sealant as described above. Sealant injection nozzle  312  injects sealant  80  in a groove corresponding to the back side of the first axial flange  22  of receiving end  20 , while sealant injection nozzle  314  injects sealant  28  in the axial groove  26 . 
         [0067]    The roll forming machine  300  preferably has elongated top and bottom rolls at stations  3  ( 303 ), 6 ( 306 ), 8 ( 308 ) and 9 ( 309 ). The elongated top and bottom rolls allow the single headed roll former to clinch the pipe blank during the forming process. To accomplish this task, the bottom rolls at stations  3  ( 303 ), 6 ( 306 ), 8 ( 308 ) and 9 ( 309 ) are attached to a longer shaft driving the bottom rolls. The top rolls at stations  3  ( 303 ), 6 ( 306 ), 8 ( 308 ) and 9 ( 309 ) are mounted on shafts ( 603 ,  606 ,  608 ,  609 ) that are allowed to pivot with the help of air cylinders ( 403 ,  406 ,  408 ,  409 ).  FIG. 12  shows the top rolls at stations  3  ( 303 ), 6 ( 306 ), 8 ( 308 ) and 9 ( 309 ) in an un-pivoted position.  FIG. 13  shows top rolls at stations  3  ( 303 ), 6 ( 306 ), 8 ( 308 ) and 9 ( 309 ) in a pivoted-up position. Shafts ( 603 ,  606 ,  608 ,  609 ) are operatively connected to air cylinders ( 403 ,  406 ,  408 ,  409 ) by clevises ( 503 ,  506 ,  508 ,  509 ). When the beginning or the end of a pipe blank approaches, visual sensors  700  actuate the air cylinders ( 403 ,  406 ,  408 ,  409 ) causing the top rolls at stations  3  ( 303 ), 6 ( 306 ), 8 ( 308 ) and 9 ( 309 ) to temporarily lift up to release pressure on the pipe blank and allow the male or female longitudinal lock to pass. Once past, the air cylinder releases the roll and again clinches the pipe blank to prevent it from shifting during the forming process. This added pressure on the pipe blank helps keep the material to stay straight in the rolls and therefore produces a much more consistent lock. If the rollers did not move up and down, they would flatten the longitudinal lock with their pressure. 
         [0068]    The roll forming machine  300  preferably includes three sets of horizontal rolls (vertical axis) located between stations  6  ( 306 ) and 7 ( 307 ), stations  7  ( 307 ) and 8 ( 308 ), and stations  8  ( 308 ) and 9 ( 309 ). The primary purpose of these rolls is to guide the pipe blank as it is being formed in the roll forming machine  300 . A first set  316  of horizontal rolls between station  6  ( 306 ) and 7 ( 307 ) guides the standing flange (first axial flange  22 ) into the next set of rolls that pinch it shut. The second set  318  of horizontal rolls stations between 7 ( 307 ) and 8 ( 308 ) as well as the third set  320  between stations  8  ( 308 ) and 9 ( 309 ) hold the flange at the desired angle and prevent the flange to move out of position, creating an uneven lock. 
         [0069]    The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.