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BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to roof flashing units and both the apparatus and method of making them and, more particularly, to the use of ultrasonic welding apparatus for making the roof flashing units. 
     2. Description of the Prior Art 
     The use of ultrasonic welding is well known and understood in the art of joining materials. Ultrasonic welding apparatus has been used to join sheet material, as illustrated in U.S. Pat. No. 4,208,001 (Martner), U.S. Pat. No. 4,525,233 (Brooks), and U.S. Pat. No. 4,737,213 (Paeglis and Hinckley). Ultrasonic welding apparatus and techniques have also been used to weld window frames, as illustrated in U.S. Pat. No. 4,856,230 (Slocum) and U.S. Pat. No. 5,105,581 (Slocum, Jr.). 
     U.S. Pat. No. 5,846,377 (Frantz et al) is a patent which refers to the welding of thermoplastic elements. 
     U.S. Pat. No. 5,902,657 (Hanson) discloses the use of ultrasonic welding for making window and door joints. 
     Roof flashing units of the prior art are typically made of aluminum and use rivets to secure their seams. There are also mechanical overlap seams. However, the seams always have leaked, and the need for caulking was obvious. However, caulking cannot be used for flat roofs, where heat from hot asphalt being applied melts the caulk. Roof flashing units include a cylinder secured to a flat plate, and both the seam of the cylinder and the seam required to secure the cylinder to the flat base plate cause leakage problems over time with respect to the caulk. 
     There are generally three types of roof flashing units, a pipe jack type, which typically goes over sewer pipes extending upwardly from the roof. A second roof flashing type is pipe flashing which typically is disposed over the flue of a gas burning appliance, such as type B gas appliances, namely hot water heaters, gas furnaces, etc. The third type of roof flashing units is the tee top. These units go over or about flues from fans which blow air out of houses, such as exhaust fans, where no heat is involved, and the like. 
     Pipe jacks generally include a base element and a pipe which extends generally perpendicular to the base element. 
     Pipe flashing units typically include a base unit and a pipe which is larger than the pipe jack and which typically includes a slant or taper of some type. The pipe element is secured to the base element. 
     A tee top includes a base unit, a pipe which may or may not have a slant to it, and a curved half cylinder panel secured to the top of the pipe to prevent rain from flowing downwardly. 
     The method and apparatus comprising the present invention is capable of making all three types of roof flashing units. 
     With the apparatus and method of the present invention, aluminum roof flashing units are ultrasonically welded, and thus the problem of the riveted seams, or the other type of seams is substantially eliminated. The tubular or cylindrical pipe element is secured to the flat base element by means of ultrasonic welding, thus allowing the roof flashing units to be used on both flat roofs and on sloping roofs. 
     SUMMARY OF THE INVENTION 
     The invention described and claimed herein includes a method for ultrasonically welding a pipe element, and for securing the ultrasonically welded pipe element to a base plate. When the pipe element and the base plate are ultrasonically welded together, a roof flashing unit is completed. The roof flashing unit is typically made of aluminum, and the aluminum parts or elements are ultrasonically welded by two ultrasonic welding units or apparatus. The two ultrasonic welders include an anvil element which is freely rotating but does move perpendicular to its rotation axis, and a horn unit against which the aluminum material is disposed and against which the aluminum is pressed during the ultrasonic welding procedure. The ultrasonic welding apparatus for ultrasonically welding the tubular element is generally horizontally disposed, while the ultrasonic welding apparatus for joining the cylindrical pipe element to the base plate is generally vertically oriented. 
     Among the objects of the present invention are the following: 
     To provide new and useful roof flashing units which are ultrasonically welded; 
     To provide new and useful aluminum roof flashing units; 
     To provide a pair of ultrasonic welders for welding roof flashing units; 
     To provide an ultrasonic welder for welding a tubular aluminum element; 
     To provide a ultrasonic welder for joining a flat base plate to a tubular pipe member; and 
     To provide new and useful apparatus for ultrasonically welding roof flashing units. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     FIG. 1 is a schematic flow diagram illustrating the beginning steps of the method of the present invention. 
     FIG. 2 is an end view taken generally along line  2 — 2  of FIG.  1 . 
     FIG. 3 is a view in partial section taken generally along line  3 — 3  of FIG.  1 . 
     FIG. 4 is a side view in partial section illustrating a step in the method of the present invention. 
     FIG. 5 is a view in partial section illustrating another sequential step in the method of the present invention. 
     FIG. 6 is a view in partial section sequentially following the step of FIG.  5 . Illustrating the result of the step illustrated in FIG.  5 . 
     FIG. 7 is a side view in partial section sequentially following FIG. 6 illustrating another step in the method of the present invention. 
     FIG. 8 is a side view illustrating the product made by the method of the present invention. 
     FIG. 9 is a side view illustrating another product made by the present invention. 
     FIG. 10 is a side view showing still another product made by the method of the present invention. 
     FIG. 11 is a side view illustrating a portion of the apparatus used in the method of making the product of FIG.  10 . 
     FIG. 12 is a front view of the apparatus of FIG.  11 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 is a schematic illustration showing the beginning steps of the method of the present invention. The method of the present invention involves the ultrasonic welding of two elements to form a roof flashing unit. Illustratively, a pipe jack will be discussed. The pipe jack includes two elements, a cylindrical pipe and a generally flat base element. Those two elements are illustrated in FIG.  1 . 
     FIG. 1 illustrates a roll of raw material, for example aluminum, from which are made two flat plates, including a generally rectangular plate  12  and a generally square plate  30 . The rectangular plate  12  is rolled into a tubular configuration or pipe  14 , with an overlapped area  16  of the aluminum material. 
     The plate  30 , which comprises a base plate, is first placed in a machine which punches a hole  34  and draws an area  32  in the plate  30  about the punched hole  34 . The drawn area extends generally upwardly and inwardly from the generally flat plate  30  and towards the hole  34 . This allows for overlap for securing the pipe  14  to the base  30  and the inward and upward taper  32  allows for a tight fit of the pipe  14 , as will be discussed below. 
     FIG. 2 is an end view of the pipe  14  of FIG. 1 showing the overlap area  16  and the generally cylindrical open area  18  within the pipe roll  14 . FIG. 3 is a view in partial section through the base plate  30  of FIG. 1, showing the drawn area  32  and the hole or aperture  34  extending in the base plate  30 . 
     FIG. 4 is a side view in partial section illustrating the ultrasonic welding of the pipe  14 . The pipe  14  is placed in a fixed sleeve  50  with the overlapped area  16 , at which the ultrasonic welding will take place, disposed against an anvil  52 . The anvil  52  is fixed in place and is connected to and supported by an anvil support arm  54 . The anvil  52  freely rotates but does not move laterally. 
     An ultrasonic unit  60  is disposed adjacent to the sleeve  50  and to the pipe  14 . At the front of the ultrasonic welding unit  60  is a horn or head  62 , appropriately aligned with the anvil  52 . The ultrasonic welding unit  60  moves upwardly for releasing the pipe  14  and for the insertion of a rolled pipe element  14  into the sleeve  50 , and then downwardly such that the head  62  essentially clamps the overlapped area  16  of the pipe roll  14  against the fixed anvil  52 . 
     As the welder  60  is actuated, ultrasonic welding takes place at the overlap area  16  to ultrasonically weld the pipe  14 . Reference number  20  in FIGS. 5 and 6 denotes the ultrasonic weld for the new finished pipe  14 . The anvil  52  rotates freely to help move the pipe  14  out of the sleeve  50  during the welding step. The purpose of the sleeve  50  is to insure the cylindrical configuration of the pipe  14  as the ultrasonic welding takes place. The horn  62  rotates to move the pipe  14  as it vibrates to accomplish the ultrasonic welding. 
     After the pipe  14  is welded at the overlap area  16 , the pipe  14  is placed over the drawn area  32  of the base panel  30 . This is shown in FIG.  5 . The two elements, the pipe  14  and the base panel or plate  30 , are then placed on a swage unit  70 . FIG. 5 schematically illustrates the swage unit  70 , the base plate  30 , and the pipe  14 . 
     The swage unit  70 , as is well known and understood, includes a plurality of blocks  72  which are generally circularly disposed, and which extend radially outwardly from a central open area. Each of the generally rectangular swage unit blocks  72  includes a inner tapered portion  74 . A stem  76  extends downwardly through the center open area of the blocks  72 . At the top of the stem  74  is an inverted conical head  78 . The diameter at the top of the inverted conical head  78  is larger than the diameter of the open area at the center of the blocks  72 . Accordingly, when the stem  76  is moved downwardly, as by appropriate force, such as pneumatic or hydraulic pressure, well known and understood in the art, the inverted conically tapered lower portion of the head  78  contacts the sloping portion  74  of the blocks and moves the blocks outwardly by cam action. 
     The diameter of the hole or aperture  34  of the plate  30  is slightly larger than the outer diameter of the blocks  72  of the swage unit  70 . The plate  30 , with the pipe  40  disposed thereon, accordingly is disposed over the swage unit  70 . 
     FIG. 6 sequentially schematically illustrates the result of the action of the swage unit  70  with respect to the base plate  30  and the pipe  14 . The blocks  72  move radially outwardly as the stem  76  moves downwardly, and the drawn area  32  moves outwardly against the pipe unit  14  under the pressure or force of the blocks  72 . The outward movement of the blocks  72  of the swage unit  70  moves the drawn area  32  outwardly until the drawn area  32  and the hole or aperture  34  are substantially identical and are generally perpendicular to the plane of the base  30 . At the same time, the lower portion of the pipe  14  is also moved outwardly slightly and there is accordingly a frictional engagement between the pipe  14  and the base  30 . As illustrated in FIG. 6, a joint area  22  of the pipe  14  is disposed against the drawn area  32  to provide the frictional engagement. The joint area  22  is also, of course. 
     FIG. 7 is a view in partial section illustrating the ultrasonic welding of the pipe  14  to the drawn area  32  of the base  30 . The ultrasonic welding of the pipe  14  to the base  30  completes the fabrication of a pipe jack  40 , which is shown in FIG.  8 . In FIG. 7, the base  30  with the pipe  14  frictionally engaged thereto is shown disposed against a rotatable anvil  80  at the now adjacently disposed areas of the pipe  14  and  32 / 34  of the base  30  at which the welding will take place. The anvil  80  includes a support arm  82  which extends upwardly from the anvil. The anvil  80  is again free to rotate to help rotate the base  30  and the pipe  14  during the ultrasonic welding procedure, but the anvil does not move laterally. 
     An ultrasonic welding tool  90  is moved against the inside of the drawn area  32 , and it includes a horn or head  92  which is, of course, aligned with the anvil  80 . The horn  92 , like the horn  52 , rotates to rotate the two units being welded, as discussed above for the welding and the movement of the pipe  14 . When the ultrasonic welding apparatus is engaged, the anvil  80  rotates freely and a joint area  36  ultrasonically welds the two elements, namely the pipe  14  and the base  30 , together to form the pipe jack  40 . The pipe jack  40  rotates by the rotation of the horn  92  until the joint area  36  is completed about the entire circumferential area of the pipe  14 . As indicated above, a completed pipe jack  40  results. FIG. 8 is a side view schematically illustrating the complete pipe jack  40 . 
     A tee top roof flashing unit  100  is shown in FIG.  9 . FIG. 9 is a side view of the tee top roof flashing unit  100 . The tee top unit  100  includes a base plate  102 , which is substantially identical to the base plate  30  of the pipe jack  40 . The tee top  100  includes a pipe  104  which is fabricated substantially the same way as discussed above for the pipe  14 , although the pipe  104  is substantially larger in diameter than that of the pipe  14 . The securing of the pipe  104  to the base  102  is substantially as discussed above, and as illustrated in FIGS. 5,  6 , and  7 . 
     A top  106  is a substantially rectangular plate curved in the configuration of a half cylindrical element and is ultrasonically welded to the top of the pipe  114  at two relatively short arcuate areas diametrically opposed to each other. One of the two ultrasonic welding areas is denoted by reference numeral  108 . 
     It will be understood that the ultrasonic welding method discussed above may also be used, as indicated above, to produce a pipe flashing  110 , a side view of which is shown in FIG.  10 . The pipe flashing unit  110  includes a base  112 , which is substantially identical to the base  30  and to the base  102 . The pipe flashing unit  110  also includes a pipe  114  which is different in configuration from the pipe  14  of the pipe flashing  40  and the pipe  104  of the tee top unit  100 . The pipe  114  is a tapered pipe, but is secured together in substantially the same way, with respect to the ultrasonic welding, as is the pipe  14  and the pipe  104 , discussed above. 
     The manufacturing of the pipe  114  is schematically illustrated in FIGS. 11 and 12. FIG. 11 is a side view of the apparatus used to ultrasonically weld the pipe  114 , while FIG. 12 is a schematic representation of the front view of a portion of the elements illustrated in FIG.  11 . For the following discussion, reference will primarily be made to FIGS. 11 and 12, but reference may also be made to FIG.  10 . 
     A split sleeve  120  is illustrated in both FIGS. 11 and 12, and the split sleeve  120  is used to hold the tapered pipe  114  after it has been rolled and prior to, and during, the ultrasonic welding step. The split sleeve  120  includes a pair of generally vee shaped slots  122  and  124  into which the opposite sides of the tapered pipe  114  are inserted. The sleeve  120  is spaced apart slightly from an anvil  130 , which is supported by a support arm  132 . As indicated above, the anvil  130 , like the anvils  52  and  80 , rotate freely. 
     Disposed above the anvil  130 , and aligned therewith, is a ultrasonic welding tool  140  with its horn  142 . As indicated by the double headed arrow, the ultrasonic welding tool moves upwardly and downwardly. As indicated by the heavy single headed arrow, the horn  142  rotates as the ultrasonic welding tool  140  is activated to accomplish the ultrasonic welding. 
     It is the rotation of the horn  142 , as well as the rotation of the horns  62  and  92 , discussed above, that causes the elements being welded to move, thus providing a continuous welded area. 
     An overlap area of the ends of the rolled pipe  114  is indicated by reference number  116  in both FIG.  11  and FIG.  12 . The ultrasonic welding takes place in the overlap area  116 . 
     An outer end  118  of the rolled sleeve  114  is manually placed or moved onto the anvil  130 , and the ultrasonic welding tool  140  is then moved downwardly to clamp the pipe  114  against the anvil  130  at the overlap area  116 . The ultrasonic welding tool  140  is then actuated to both accomplish the welding step and to rotate the horn  142  to move the pipe  114  along its full length to provide a continuous bead the full length of the horn  114 . 
     It will be noted that using a split sleeve  120 , the angle or size of the pipe  114  is entirely immaterial. 
     It will be noted that the anvil  130  is shown in FIG. 12 spaced apart downwardly from the split sleeve  120 . The purpose of this is for clarity of illustration. In actuality, as may be understood from FIG. 11, the height of the anvil  130 , while spaced in front of the sleeve  120 , is sufficient to easily allow the pipe  114  to move onto the anvil  130 . 
     The joint area of the pipe  114  and the base  112  is rendered generally perpendicularly to the plane of the base  102 , substantially as discussed above, by a swaging operation, also as discussed above. Thus, the joint area of the two elements is substantially as shown in FIG. 6, and is formed in substantially the same way as illustrated in FIG.  5 . The taper of the pipe  114  is relatively immaterial with respect to the ultrasonic welding steps as outlined above. 
     While the principles of the invention have been made clear in illustrative embodiments, there will be immediately obvious to those skilled in the art many modifications of structure, arrangement, proportions, the elements, materials, and components used in the practice of the invention, and otherwise, which are particularly adapted to specific environments and operative requirements without departing from those principles. The appended claims are intended to cover and embrace any and all such modifications, within the limits only of the true spirit and scope of the invention.

Summary:
Ultrasonic welding apparatus is used for making roof flashing units. The roof flashing unites typically include a generally flat aluminum plate and a cylindrical aluminum element joined to the generally flat plate. Two ultrasonic welders are used to make the roof flashing unit, including a horizontally disposed ultrasonic welder for the cylindrical element and a horizontally disposed ultrasonic welder for joining the cylindrical unit to the generally flat plate.