Abstract:
An automatic tube tee forming and trimming system uses a single apparatus for milling a hole in a tube, pulling a forming die through the milled hole, and face trimming the resulting pullout joint to the desired height. The forming die is pulled out through the hole via a universal driver which is simply attached to the drawbar without requiring any twisting to lock the assembly. The system may automatically conduct each of the steps once the tube is loaded into the apparatus. The apparatus completes the tube tee forming and trimming process in a relatively small cell, without the need to travel out to another factory area, within a relatively short period of time, and with minimal use of manual labor.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention generally relates to a tube tee forming and trimming system and, more specifically, to an automated, self-contained tube tee forming and trimming system for forming and trimming a pullout joint.  
           [0002]    A pullout joint, also known as a tube tee, is formed in a tube to allow other tubes or fittings to be welded to the parent tube. Referring to FIG. 1, there is shown one example of a pullout joint  12  formed in a tube  10 . Pullout joints must be accurately located, correctly formed, and trimmed to the required height.  
           [0003]    A conventional pullout joint is made by attaching the part to a work surface and cutting an elliptical hole in the tube using either a laser or an abrasive water jet. The periphery of the cutout is then manually ground and polished to remove the heat affected material and cutting marks that will cause the material to crack when formed. After grinding, the part is cleaned to remove all anti spatter and grinding grit.  
           [0004]    The area to be formed is coated with a forming lubricant. The detail is located in a form die in a forming press and clamped in place. A punch is heated to 500° F. using an induction-heating coil. After reaching the pre-set temperature, the punch is manually inserted into the tube and onto a drawbar that protrudes into the tube, through the elliptical cutout. The punch is rotated 90° and locked onto the drawbar. The press is then activated and the punch is drawn through the tube, forming the pullout. The part is removed from the tool and routed to the clean line to remove the forming lubricant.  
           [0005]    After cleaning, the part is put in an assembly fixture and the pullout is scribed for the trim height, removed from the fixture and trimmed to the scribe line using a disk sander. After grinding the pullout to the scribe line, it is deburred and manually cleaned.  
           [0006]    The above described conventional pullout forming and trimming process is quite lengthy, requiring large capital equipment and the use of several areas of the factory for the various steps.  
           [0007]    As can be seen, there is a need for an improved tube tee forming and trimming system that solved both the technical and logistical issues related to forming and trimming a pullout joint. More specifically, there is a need for an automated, self-contained pullout joint forming and trimming system that completes the process in a relatively small cell, without the need to travel out to another factory area, within a relatively short period of time, and with minimal use of manual labor.  
         SUMMARY OF THE INVENTION  
         [0008]    In one aspect of the present invention, a tee forming and trimming system comprises a milling head for milling a hole in a surface; a forming die forming a rough pullout joint when pulled from an inside region of the surface through said hole; a face trim head for trimming said rough pullout joint into a finished pullout joint; and a loading/moving system for automatically moving the surface from a position where the milling head makes the hole to a position where the forming die makes the pullout joint to a position where the face trim head trims the rough pullout joint into the finished pullout joint.  
           [0009]    In another aspect of the present invention, a tube tee forming and trimming system comprises a milling head for milling a hole in a tube; a forming die forming a rough pullout joint when pulled from an inside region of the tube through the hole; a drawbar for pulling the forming die through the hole; a hydraulic cylinder for driving the drawbar; a face trim head, automatically interchangeable with the milling head, for trimming the rough pullout joint into a finished pullout joint; and a tube loading/moving system for automatically moving the tube from a position where the milling head makes the hole to a position where the forming die makes the pullout joint to a position where the face trim head trims the rough pullout joint into the finished pullout joint.  
           [0010]    In yet another aspect of the present invention, a tube tee forming and trimming system for forming a pullout joint in aircraft ducting comprises a milling head for milling a hole in a titanium tube; a forming die forming a rough pullout joint when pulled from an inside region of the titanium tube through the hole; a drawbar for pulling the forming die through the hole; a hydraulic cylinder for driving the drawbar; a universal driver having a diameter smaller than a diameter of the forming die; the universal driver being located distal of the forming die relative to the drawbar; the drawbar attaching to the universal driver when the drawbar is extended into the hole and through the forming die, wherein the forming die is pulled up through the hole when the hydraulic cylinder drives the drawbar away from the titanium tube; a face trim head, automatically interchangeable with the milling head, for trimming the rough pullout joint into a finished pullout joint; and a tube loading/moving system for automatically moving the titanium tube from a position where the milling head makes the hole to a position where the forming die makes the pullout joint to a position where the face trim head trims the rough pullout joint into the finished pullout joint.  
           [0011]    In a further aspect of the present invention, a tube tee forming and trimming system comprises a milling head for milling a hole in a tube; a forming die forming a rough pullout joint when pulled from an inside region of the tube through the hole; a drawbar for pulling the forming die through the hole; a hydraulic cylinder for driving the drawbar; a universal driver having a diameter smaller than a diameter of the forming die; the universal driver being located distal of the forming die relative to the drawbar; a presentation arm positioning the forming die and the universal driver in a position inside the tube such that when the drawbar is lowered into the tube, the drawbar is automatically aligned with the forming die and universal driver; a driver latch formed in the universal driver; the driver latch having a right half, a left half, and a top plate; a hole in the top plate such that when the left half is mated with the right half, the hole is smaller than the outside diameter of the drawbar; the left half and the right half of the driver latch resiliently contained in the universal driver such that when the drawbar extends into the universal driver, the left half and the right half elastically deform apart from each other; a groove in the drawbar being cut in a width at least as wide as the top plate, whereby when said groove reaches the top plate, the right half and the left half elastically return toward their original, mated positions, thereby locking the drawbar onto the universal driver; a face trim head, automatically interchangeable with the milling head, for trimming the rough pullout joint into a finished pullout joint; and a tube loading/moving system for automatically moving the tube from a position where the milling head makes the hole to a position where the forming die makes the pullout joint to a position where the face trim head trims the rough pullout joint into the finished pullout joint.  
           [0012]    In still a further aspect of the present invention, a pullout forming die system comprises a drawbar for pulling a forming die through a material; a universal driver having a diameter smaller than a diameter of the forming die; the universal driver being located distal of the forming die relative to the drawbar; a driver latch formed in the universal driver; the driver latch having a right half, a left half, and a top plate; a hole in the top plate such that when the left half is mated with the right half, the hole is smaller than the outside diameter of the drawbar; the left half and the right half of the driver latch resiliently contained in the universal driver such that when the drawbar extends into the universal driver, the left half and the right half elastically deform apart from each other; and a groove in the drawbar being cut in a width at least as wide as the top plate, whereby when the groove reaches the top plate, the right half and the left half elastically return toward their original, mated positions, thereby locking the drawbar onto the universal driver.  
           [0013]    In still a further aspect of the present invention, a method for forming and trimming a tube tee comprises milling a hole in a tube; pulling a forming die through the hole to form a rough pullout joint; trimming the rough pullout joint with a face trim head to form a finished pullout joint; and automatically moving the tube from a position where the milling head makes the hole to a position where the forming die makes the pullout joint to a position where the face trim head trims the rough pullout joint into the finished pullout joint. 
       
    
    
       [0014]    These and other features, aspects and advantages of the present invention will become better understood with reference to the following drawings, description and claims.  
       BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]    [0015]FIG. 1 is a perspective view showing a pullout joint formed in a tube;  
         [0016]    [0016]FIG. 2 is a perspective drawing of the tube trimming and forming apparatus according to one embodiment of the present invention in a part load position;  
         [0017]    [0017]FIG. 3 is a perspective drawing of the tube trimming and forming apparatus according to one embodiment of the present invention in a milling position;  
         [0018]    [0018]FIG. 4 is a perspective drawing of the tube trimming and forming apparatus according to one embodiment of the present invention moving from the milling position to a pullout position;  
         [0019]    [0019]FIG. 5 is a perspective drawing of the tube trimming and forming apparatus according to one embodiment of the present invention in a pullout forming position;  
         [0020]    [0020]FIG. 6 is a perspective drawing of the pullout forming portion of the tube trimming and forming apparatus according to one embodiment of the present invention;  
         [0021]    [0021]FIG. 7 is a schematic drawing showing the forming die system according to one embodiment of the present invention;  
         [0022]    [0022]FIG. 8 is a perspective drawing of the tube trimming and forming apparatus according to one embodiment of the present invention once the rough pullout joint is formed;  
         [0023]    [0023]FIG. 9 is a perspective drawing of the tube trimming and forming apparatus according to one embodiment of the present invention in a face trimming position;  
         [0024]    [0024]FIG. 10 is a perspective drawing of the tube trimming and forming apparatus according to one embodiment of the present invention in a part unload position;  
         [0025]    [0025]FIG. 11 is a schematic drawing showing the pullout forming die system according to one embodiment of the present invention;  
         [0026]    [0026]FIG. 12 is a close-up drawing showing the driver latch part used in one embodiment of the present invention; and  
         [0027]    [0027]FIG. 13 is a perspective drawing showing the universal driver used in one embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0028]    The following detailed description is of the best currently contemplated modes of carrying out the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.  
         [0029]    The present invention provides an automated tube tee forming and trimming system useful for forming and trimming pullout joints in a tube. The ability to provide accurate and simple formation of pullout joints in a tube may be useful in a wide variety of industries using the movement of air and fluid through tubes. For example, the aircraft industry uses ducting for the movement of air, for fuel vent tubes and for fuel feed lines. The food processing industry and wineries also use tubes of various sizes and designs.  
         [0030]    Conventional pullout joint forming and trimming methods require a significant amount of factory space to perform the various steps in the forming and trimming process. The automated tube tee forming and trimming system of the present invention addresses this issue by forming and trimming a pullout joint in a single, self-contained apparatus.  
         [0031]    Conventional pullout joint forming and trimming methods require a significant amount of user intervention to make the final product. The automated tube tee forming and trimming system of the present invention addresses this issue by forming and trimming a pullout joint in an automated fashion, requiring very little operator time and intervention.  
         [0032]    Conventional pullout joint forming and trimming methods require the drawbar to twist to lock into the form die prior to pulling the form die through the hole in the tube. The automated tube tee forming and trimming system of the present invention provides a simple locking mechanism to lock the drawbar into the form die without requiring any rotational motion.  
         [0033]    Referring to FIG. 2, there is shown a perspective drawing of the tube trimming and forming apparatus of the present invention in a part load position. A pullout forming portion  22  may be attached to a milling portion  20 . Milling portion  20  may be any conventional machining tool. For example, milling portion  20  may be a Fryer Machine Systems MC-20 computer numerical control (CNC) vertical 3-axis mill machining center. The CNC machine controller (not shown) may be used to drive the 3-axis mill, as well as activate pullout forming portion  22  and control a tube loading/moving system  28 .  
         [0034]    A tube  10  may be placed in a tube holder  24  of tube loading/moving system  28 . A top portion  30  of tube holder  24  may have an opening to allow a milling head  26  to pass therethrough.  
         [0035]    Referring now to FIG. 3, there is shown a perspective drawing of the tube trimming and forming apparatus of the present invention in a milling position. Tube loading/moving system.  28  may move the loaded tube  10  from the loading position to a milling position. Milling head  26  may move toward tube  10 , cutting a predetermined-sized elliptical hole  27  into tube  10 .  
         [0036]    Referring to FIG. 4, there is shown a perspective drawing of the tube trimming and forming apparatus of the present invention moving from the milling position to a pullout position. Milling head  26  may move from a cutting position to it original, non-cutting position. Tube loading/moving system  28  may slide tube  10 , now having an elliptical hole cut therethrough, from the milling position to the pullout position. Elliptical hole  27  may then be aligned with pullout forming portion  22 .  
         [0037]    Referring on to FIGS. 5, 6 and  7 , there are shown perspective drawings of the tube trimming and forming apparatus of the present invention. A hydraulic cylinder  32  may drive a drawbar  34  through elliptical hole  27  of tube  10  and through a hole in a forming die  36 . Forming die  36  may have an outside diameter sized at the desired inside diameter of the pullout joint.  
         [0038]    A universal driver  40  may be positioned distal to forming die  36 , relative to drawbar  34 , to engage an engagement end  42  of drawbar  34 . Once drawbar  34  engages universal driver  40 , hydraulic cylinder  32  may move to lift forming die  36 , along with universal driver  40 , through the elliptical hole in tube  10 , forming a rough pullout joint—such as pullout joint  12 —therein. Universal driver  40  may have a diameter smaller than that of forming die  36 , thereby allowing universal driver  40  to pass through the rough pullout joint—such as pullout joint  12 —along with forming die  36 . Universal driver  40  may be used with any sized forming die  36 , so long as the diameter of universal driver  40  is smaller than that of forming die  36 .  
         [0039]    A forming die presentation arm  38  may be used to align forming die  36  with drawbar  34 . If a pullout joint is to be formed at a central portion of a very long tube, forming die presentation arm  38  may be eliminated and forming die  36  manually located in tube  10  beneath the elliptical hole.  
         [0040]    Referring now to FIG. 8, there is shown a perspective drawing of the tube trimming and forming apparatus of the present invention once the rough pullout joint is formed. After hydraulic cylinder  32  pulls out of tube  10 , the rough pullout joint is formed. At this point, milling head  26  (not shown) may be changed to a face trim head  44 . Tube loading/moving system  28  may slide tube  10  from a pullout forming position back to the original milling position.  
         [0041]    Referring to FIG. 9, there is shown a perspective drawing of the tube trimming and forming apparatus of the present invention in a face trim position. Face trim head  26  may lower to trim excess material from the rough pullout joint and to make the rough pullout joint of the correct drawing height.  
         [0042]    Referring to FIG. 10, there is shown a perspective drawing of the tube trimming and forming apparatus of the present invention in an unload position. After face trim head  44  completes the trimming of the pullout joint, face trim head  44  may rise and tube loading/moving system  28  may move tube  10  to an unloading position. Tube  10  may be removed to give completed part having pullout joint  12 .  
         [0043]    Referring now to FIGS. 7, 11,  12  and  13 , there is shown more detailed views of the universal driver  40 /forming die  36  assembly used to receive engagement end  42  of drawbar  34 . A driver latch  48  may be made from a left half  48 L and a right half  48 R. Left half  48 L and right half  48 R come together to form a top plate  56  of driver latch  48  having a hole  52  in the center thereof. Hole  52  may be made at approximately the same diameter of drawbar  34 . From each of left half  48 L and right half  48 R may extend a left leg  50 L and a right leg  50 R.  
         [0044]    A groove  54  at engagement end  42  of drawbar  34  may be made to give drawbar a reduced diameter approximately the same as the diameter of hole  52  when right half  48 R and left half  48 L are mated. Groove  54  may have a width approximately the same as the width of top plate  56  of driver latch  48 .  
         [0045]    Driver latch  48  may be installed in universal driver  40  as shown in FIG. 11. A channel  46  may be made around the circumference of universal driver  40  as well as in a portion of left leg  50 L and right leg  50 R to form a continuous channel about universal driver  40 . An elastically resilient band (not shown) may be placed in channel  46  to maintain a pressure on left leg  50 L and right leg  50 R, thereby keeping left half  48 L and right half  48 R pressed together. The elastically resilient band may be made of any material that provides sufficient resiliency against left leg  50 L and right leg  50 R. Such materials may include metal bands or clips as well as rubber bands or o-rings.  
         [0046]    When drawbar  34  is inserted through forming die  36 , through universal driver  40  and into hole  52  of driver latch  48 , the outside diameter of drawbar  34  presses left half  48 L and right half  48 R resiliently apart. Once groove  54  of drawbar  34  is aligned with top plate  56 , left half  48 L and right half  48 R resiliently snap back into groove  54 , thereby locking universal driver  40  onto drawbar  34 . Thus, when drawbar  34  is raised, universal driver  40  is raised against forming die  36 , raising forming die  36  through the hole in the tube, thereby creating the rough pullout joint.  
         [0047]    Right arm  5 OR and left arm  50 L may extend beyond a bottom face  58  of universal driver  40 . This allows for a user, or another device to resiliently move right arm  50 R and left arm  50 L to separate right half  48 R and left half  48 L out of groove  54 . This allows for the simple remove of forming die  36  and universal driver  40  from drawbar  34 .  
         [0048]    The present invention may be used to make pullout joints of any size in practically any diameter tube. The present invention is especially useful in making pullout joints from about 1 to about 5 inches in a tubular material.  
         [0049]    The tubular material may be any material through which a pullout joint may be formed. Such materials include, but are not limited to titanium, stainless steel, thin-walled inconel, copper, brass, and alloys, such as high nickel alloys.  
         [0050]    The present invention has been described using a tubular material for making the pullout joint therein. However, the invention is not meant to be limited to materials of any particular size or shape. For example, a rectangular duct may be used as a starting material to have a pullout joint formed therethrough.  
         [0051]    The present invention has been described using an elliptical hole being first milled in the tubular material. As one having ordinary skill in the art could envision, a hole of such shape is made to minimize the excess material that must be trimmed when face trimming the rough pullout joint to the desired drawing height. The present invention, however, is not meant to be limited to initial holes of any particular shape. For example, round holes may be milled in the tubular material and the excess trimmed in the trimming step.  
         [0052]    It should be understood, of course, that the foregoing relates to preferred embodiments of the invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims.