HK1144489A - A percussion instrument - Google Patents

Description

Percussion instrument

The application is a divisional application of Chinese patent application with the application number of 200580046440X (PCT/US2005/046347), the application date of 12/21/2005, and the invention name of "method for manufacturing percussion instrument".

Technical Field

The present invention relates to a method for manufacturing a musical instrument. More particularly, the present invention relates to a method of manufacturing a percussion instrument from a polyvinyl chloride material.

Background

Percussion instruments are well known in the art. The method of manufacturing such percussion instruments typically involves a number of separate manufacturing steps. The steps of the manufacturing method use a plurality of specific tools and a plurality of different discrete components that are assembled together by fasteners or clamps. Percussion instruments typically have multiple parts such as a housing, chrome-plated fittings, a stand, and a skin. Heretofore, a decisive factor in achieving excellent sound quality and ensuring durability has been the use of a wooden casing. The wood shell is preferably made in a circular shape, and a skin is mounted on the wood shell. A great deal of research and development effort has been directed to wood shell manufacturing techniques.

The wood shell may be constructed of 6 to 8 wood plies, typically using different woods. These include mahogany, friett (falcata) wood, birch, and maple. Materials commonly used for the housing include single wood plies, solid wood, or man-made materials such as fiberglass, pressed steel, plexiglass, and resin composites. Wood shells or other composite shells may be completed by laminating the wood shells in a plastic manner. Wood shells can also be made in a number of different colors and have many effects such as a multi-colored shell. Natural wood can be stained or left natural and/or varnished. The steel housing is typically chrome plated and has a glass tint added.

Next, one or two cast or pressed metal rings are added to the wood shell. The cast or pressed metal rings are connected by means of tensioning screws or lugs into nut boxes (nut boxes) bolted to the wood shell. Such tension rod assemblies require precise machining, casting, and assembly, and sometimes require the addition of labor to enable predictable and assured tuning without dampening resonance or introducing additional vibration.

The mounting system may vary greatly from a simple die block that receives and clamps onto a housing of a rod that is joined to a clamp or holder, to more complex devices that utilize clamps. The clamp system allows for the engagement of the drum without requiring holes in the wood drum shell. The clamp is joined to the wood shell at a node point with two bolts to allow the wood shell to vibrate freely without destroying the dynamic range of the shell. The nodal point is the location on the hull that has the least amount of vibration, thereby allowing the least amount of influence on the resonance of the wood hull.

Although very good percussion instruments can be made in this manner, these methods of making percussion instruments are expensive and require a great deal of labor. This labor and the amount of expensive fine wood material used to form the wood shell increases costs. They also increase the overall time for manufacturing the percussion instrument. In addition, various forms of composite housings have also been in use for some time now. All of the foregoing methods use resin-based materials, including glass fibers, through a molding process. This molding process requires a permanent mold. The method of the present invention eliminates the need for such expensive molds.

Accordingly, there is a need for a method of manufacturing a percussion instrument that obviates one or more of the foregoing disadvantages and drawbacks of the prior art.

Disclosure of Invention

It is an object of the present invention to provide a percussion instrument that can be made of polyvinyl chloride material.

It is an object of the present invention to provide a percussion instrument that can be manufactured from a standard polyvinyl chloride material tube that is readily available and need not be dedicated to the manufacture of percussion instruments.

It is another object of the present invention to provide a percussion instrument that can be manufactured from polyvinyl chloride in a cost effective and quick manner.

It is yet another object of the present invention to provide a method of manufacturing a percussion instrument that is efficient and does not sacrifice the sound quality of the percussion instrument.

It is yet another object of the present invention to provide a percussion instrument made of stretched polyvinyl chloride.

It is yet another object of the present invention to provide an apparatus that can be installed inside a hollow member such as a pipe made of polyvinyl chloride, heat the polyvinyl chloride pipe, and expand the polyvinyl chloride pipe without breaking the polyvinyl chloride pipe to form a drum shell.

It is yet another object of the present invention to provide an apparatus that can be installed inside a polyvinyl chloride pipe and has a plurality of resilient arms that expand the polyvinyl chloride pipe to form a drum shell without rupturing the polyvinyl chloride pipe.

It is a further object of the present invention to provide a drum shell made of a shell of polyvinyl chloride material and having acoustic properties similar to those of a wooden drum shell.

It is yet another object of the present invention to provide a method of manufacturing polyvinyl chloride drum shells from inexpensive raw materials in a more efficient (including less time consuming) manner than wood drum shells.

It is a further object of the present invention to provide a method of making a percussion instrument from a polyvinyl chloride tube having a longitudinal axis, wherein the polyvinyl chloride drum shell is formed by expanding the polyvinyl chloride tube from the longitudinal axis in a direction outwardly from the inner surface of the polyvinyl chloride tube.

These and other objects and advantages of the present invention are achieved by a method of manufacturing a percussion instrument according to the present invention. The method has the step of disposing a first member into the liquid, the first member having a first diameter and the first member having a first end and a second end. The method also has the steps of heating the liquid and expanding the first end of the first member to a second diameter. The method also has the step of cooling the expanded first end and the step of mounting a skin over the first end.

Drawings

Fig. 1 is a front perspective view of the apparatus for expanding polyvinyl chloride pipes of the present invention, which is provided with a press.

Fig. 2 is a front perspective view of the device of fig. 1 placed in a polyvinyl chloride pipe and a plurality of resilient arms extending out of the polyvinyl chloride pipe.

Fig. 3 is a top perspective view of the apparatus of fig. 1, wherein the polyvinyl chloride pipe and apparatus are submerged in a boiling liquid in the vessel and the pressure vessel exerts a force thereon.

Fig. 4 is a front view of the apparatus of fig. 3 taken from the boiling liquid in the vessel, with the polyvinyl chloride pipe being stretched accordingly.

Fig. 5 is a top isometric view of a mold placed in a first end of a stretched polyvinyl chloride pipe for reintroduction into a boiling liquid.

Fig. 6 is a perspective view of the stretched polyvinyl chloride pipe taken from the boiling liquid in the vessel, and the polyvinyl chloride pipe is flattened into a spherical shape.

Fig. 7 is a top view of a polyvinyl chloride drum shell having a first circular resilient member inserted therein.

Fig. 8 is a top view of a wooden mold placed in an opening of a polyvinyl chloride drum shell for forming a desired curve when reheating the polyvinyl chloride drum shell.

Fig. 9 is a perspective view of a stretched polyvinyl chloride pipe reheated in a boiling liquid in a vessel to form a desired curve.

Fig. 10 is a top view of a percussion instrument having a support head and a desired curve for mounting a drum head thereon.

Fig. 11 is a perspective view of a collapsible mold adjacent an expanded polyvinyl chloride pipe for another method of forming a drum.

Fig. 12 is a perspective view of a collapsible mold in the stretched polyvinyl chloride pipe of fig. 11.

Fig. 13 is a perspective view of a collapsible mold in the stretched polyvinyl chloride pipe of fig. 11, both placed in a container of heated liquid.

Fig. 14 is a perspective view of the collapsible mold in the stretched polyvinyl chloride pipe of fig. 13, both being removed from the container of heated liquid.

Fig. 15 is a top view of a collapsible mold in an expanded polyvinyl chloride pipe wherein the outer surface of the expanded polyvinyl chloride pipe is flattened by heating the liquid bath of fig. 14.

Figure 16 is a bottom view of a reinforcement member attached to the base plate for attachment to the expanded polyvinyl chloride pipe of figure 15.

Fig. 17 is a perspective view of the reinforcement of fig. 16 connected to the stretched polyvinyl chloride pipe of fig. 15.

Fig. 18 is a perspective view of a combination reinforcement on a base plate and a stretched polyvinyl chloride pipe.

Fig. 19 is a perspective view of a combination stiffener and stretched polyvinyl chloride pipe inserted into a vessel for connecting the stiffener to the stretched polyvinyl chloride pipe.

Fig. 20 is the combined reinforcement and stretched polyvinyl chloride pipe having been removed from the container.

Figure 21 shows the cooled combined stiffener and stretched polyvinyl chloride pipe with the base plate removed.

Fig. 22 shows the combined reinforcement and stretched polyvinyl chloride pipe connected to each other with the splittable mold split for removal.

Fig. 23 shows the combined reinforcement and stretched polyvinyl chloride pipe connected to each other with the collapsible mould being pulled from the completed drum.

Fig. 24 shows another exemplary embodiment of a drum having a carcass of the present invention.

Fig. 25 is a close-up view of fig. 24 showing a second lower loop of the armature of fig. 23.

Detailed Description

Referring to the drawings, and more particularly to FIG. 1, a method of making the percussion instrument of the present invention is shown. The percussion instrument of the present invention is generally designated by the reference numeral 10. Percussion instrument 10 is intended to be made of a commercially readily available polyvinyl chloride material formed into a hollow sleeve or tube 12 having a shaped cross-section as shown in fig. 2. One skilled in the art will recognize that any thermoplastic or polymeric material may be used and fall within the scope of the present invention. Preferably, the polyvinyl chloride pipe 12 has one or more layers of polyvinyl chloride at one or more locations of the pipe for increasing the thickness at preselected locations. Preferably, the polyvinyl chloride pipe 12 has a middle thickness (middle thickness) of class "D". Alternatively, the polyvinyl chloride pipe 12 has an "AW" rating. Also, preferably, the polyvinyl chloride pipe 12 is a white or gray pipe having a diameter of four inches, a wall thickness of two millimeters, and a length of forty-six centimeters. In addition, a second layer of polyvinyl chloride pipe is placed on the polyvinyl chloride pipe 12 for reinforcing the polyvinyl chloride pipe 12 with the second layer having a complementary ruler and a length of four centimeters. Alternatively, the polyvinyl chloride pipe 12 may be white and may have a diameter of four inches and a wall thickness of two millimeters and a length of about fifty-six centimeters, with the second layer being about four centimeters long. Additionally, in another embodiment, the polyvinyl chloride pipe 12 may have a diameter of five inches and a wall thickness of 2.6 millimeters and a length of sixty-six centimeters, with the second layer being approximately four centimeters long. Additionally, in another embodiment, the polyvinyl chloride pipe 12 may have a length of seventy-seven centimeters and a diameter of six inches and may be a gray grade D pipe. Those skilled in the art will appreciate that the polyvinyl chloride pipe 12 may have other dimensions and other thicknesses, and the present invention is not strictly limited to the above-described embodiments. Alternatively, percussion instrument 10 may be made of a thermally reactive plastic that may have the same or similar properties as polyvinyl chloride. Preferably, the thermally reactive plastic material can be reheated and reshaped in a similar manner to polyvinyl chloride.

The method of the present invention is advantageous, uses commercially readily available materials that are advantageous over wood and other materials used in the construction of the shell, eliminates many expensive manufacturing processes, and has the unexpected advantage of manufacturing percussion instruments that are generally of the same quality as other percussion instruments made by time consuming and expensive manufacturing methods.

The method of the present invention reduces the amount of time used to manufacture percussion instruments such as bangka drums, snares, drums, drum shells, or any other acoustic instrument known in the art. The method of the present invention is advantageous because the sound quality of the percussion instrument is not sacrificed and is in fact comparable to utilizing an advantageous wood shell. This simultaneous sound quality and reduced cost has unexpected advantages over the prior art. The teachings of the prior art drum shells deviate from the present invention because they encourage the use of high quality wood shells made of expensive materials to ensure sound quality such as drum shells.

More preferably, the percussion instrument 10 is a drum shell. However, the present invention may be used with any acoustic instrument known in the art. Furthermore, the method does not necessarily have to be used for manufacturing such an acoustic device. It may be used to make other containers, cups, pots, bowls, or other items known in the art for holding liquids or solids.

Referring to fig. 1, fig. 1 shows an apparatus 14 for making a percussion instrument 10 from a polyvinyl chloride pipe 12. The device 14 is preferably made of one or more resilient materials, such as steel, metal, aluminum, resilient polymers that can withstand high temperatures, composite materials that can withstand high temperatures while maintaining structural integrity so that the device 14 does not melt or deform when heated, or any other resilient material.

It is further preferred that the device 14 be of a predetermined size such that one portion of the device can be compressed to fit into the polyvinyl chloride pipe 12 and through the polyvinyl chloride pipe 12 and such that another, second portion of the device can extend out of the polyvinyl chloride pipe. The size of the device 14 depends on the diameter of the polyvinyl chloride pipe 12 used. It is preferred that the device 14 have a body 16 with a plurality of resilient bars 18, the resilient bars 18 being arranged in a cylindrical pattern as shown. In one embodiment of the invention, the device 14 has first through twelfth resilient bars connected to the support 20. A support 20 is connected to the plurality of resilient bars 18 and serves as a base for supporting one or more portions of the device. Preferably, the twelve resilient bars 18 form the body 16 with a wide portion 22 and a narrow portion 24 and a second wide portion 26. As shown, the body 16 forms an hourglass-like structure. Attached to the resilient lever 18 at the wide portion 22 of the device 14 are a plurality of resilient arms 28. The resilient arms 28 are made of the same or different material relative to the resilient stem 18 of the body 16 and may be metal, aluminum, steel, composite, thermoplastic material capable of withstanding high temperatures, or other resilient material.

Each spring arm 28 is connected to each spring bar 18 by a connection point 30. Preferably, the device has two sets of resilient arms 28 that are pressed outwardly from the device 14. The attachment point 30 is adapted so that the resilient arm 28 can move freely as indicated by arrow a in an inward direction toward the inner surface of the resilient lever 18 and opposite the longitudinal axis of the body 16. In one embodiment, the connection point 30 is a roller bearing. However, the connection point 30 may be any other structure known in the art, such as a pivot, clamp, hinge, or any other suitable structure that allows movement of the resilient arm 28 in the direction of reference arrow A.

The device 14 has a press 32. The press 32 is preferably a resilient member that contacts the resilient arm 28. The forcer 32 exerts a force on each resilient arm 28 and urges each resilient arm in a first direction perpendicular to the longitudinal axis of the body 16. The press 32 is preferably a triangular resilient member and has a triangular cross-section. The press 32 is preferably connected to and powered by a hydraulic power source for movement downwardly in a direction parallel to the longitudinal axis of the body 16. Alternatively, the press 32 may push the resilient arm 28, which resilient arm 28 in turn pushes the dome-shaped member. The dome-shaped member is preferably located inside the device 14 between the resilient arms 28. The dome-shaped member preferably lifts and pushes the resilient arm 28 outwards by virtue of both the dome-shaped member and the resilient arm being connected to the threaded rod. Preferably, the hydraulic source is a five or ten ton hydraulic jack, an automobile jack or any other hydraulic source known in the art. The hydraulic source may be operated using air, oil or manual jacking as is well known in the art. Once powered, the forcer 32 moves the resilient arm 28, the resilient lever 18, or both the resilient arm and the resilient lever in a direction perpendicular to the longitudinal axis of the body 16.

Fig. 2 shows a polyvinyl chloride or polymer-based pipe 12 placed around a device 14. The polyvinyl chloride pipe 12 surrounds the wide portion 22, the narrow portion 24, and the second wide portion 26 of the body 16, and a portion of the device 14 extends out of the polyvinyl chloride pipe. As shown, the resilient bar 18 fits into the polyvinyl chloride pipe 12, and the resilient arms 28 extend out of the opening 34 of the polyvinyl chloride pipe. As shown, the press 32 is held in an initial position in which the resilient arms 28 surround the press. As will be appreciated by those skilled in the art, fig. 2 shows an initial starting position of the apparatus 14 for carrying out the method.

Referring now to fig. 3, the device 14 also has a container 36, which container 36 is a large tank or vat made of a resilient material that can withstand temperatures in excess of several hundred degrees celsius. The container 36 is preferably made of galvanized steel, metal, aluminum, or other resilient material and may be filled with a liquid 38 as shown. The device 14 has a heater thermally connected to the container 36 to heat the liquid 38 therein. The container 36 is sized so that the polyvinyl chloride pipe 12 is almost completely submerged therein. In the preferred embodiment, the liquid 38 is water. However, it will be appreciated by those skilled in the art that the liquid may be any suitable liquid known in the art, such as water with a solvent or catalyst therein.

As shown, the device 14 is placed in a container 36 with the polyvinyl chloride pipe 12. The liquid 38 reaches almost the boiling point and brings the polyvinyl chloride pipe 12 to a transition state. In the transition state, the material state of the polyvinyl chloride pipe 12 changes from the solid state to the malleable state. Preferably, the polyvinyl chloride pipe 12 is in boiling water for about one minute before becoming malleable and expanding. Also, it is preferred that the polyvinyl chloride pipe 12 have one or more additional layers of five centimeters of polyvinyl chloride pipe material at or adjacent the opening 34 that overlaps the polyvinyl chloride pipe 12. The press 32 in the initial position is then contacted and driven by hydraulic means (not shown). The hydraulic device applies a force to the forcer 32. The press 32 then exerts this force on the plurality of resilient arms 28, and the resilient arms 28 then contact the polyvinyl chloride pipe 12 and urge the polyvinyl chloride pipe 12 in a transverse, perpendicular direction relative to the longitudinal axis of the main body 16. The polyvinyl chloride pipe 12 is then expanded from a first diameter to a second diameter that is greater than the first diameter. The polyvinyl chloride pipe 12 is preferably expanded in a direction from the inside of the polyvinyl chloride pipe to the outside of the polyvinyl chloride pipe by the elastic bar 18, the elastic arm 28, or both.

Fig. 4 shows the apparatus 14 in an elevated position relative to the vessel 36 and the press 32 in a second position or partially within the polyvinyl chloride pipe 12. As shown in fig. 4, the polyvinyl chloride pipe 12 now has a larger second diameter as desired by the operator of the apparatus 14, or automatically set, such as by an automated system or software system. The method also has the step of repeating the steps for the opposite side of the polyvinyl chloride pipe 12, for the second expansion side 40 and thus forming the drum shell 10 as described above.

Fig. 5 shows a drum shell 10 made of polyvinyl chloride pipe 12. The drum shell 10 has a first enlarged diameter 42 and a second enlarged diameter 44 opposite the first diameter. When the drum shell 10 cools, it has a plurality of striations 46 formed in its outer surface 48. The plurality of striations 46 may adversely affect one or more acoustic properties of the drum shell 10. Therefore, the method also has the step of inserting the circular mold 50 into the first enlarged end portion 52 of the drum shell 10. The mold 50 is preferably in two-part form with the bottom portion having a stem connected to the top portion and made of an elastomeric material capable of withstanding high temperatures. As shown, the mold 50 has a manipulator arm 54 disposed through the centermost portion of the mold for manipulating the mold. The mold 50 is inserted into the first expanded end 52 of the polyvinyl chloride drum shell such that the outer edge 56 of the drum shell 10 contacts the outer periphery 58 of the mold 50.

Referring now to fig. 6, both the mold 50 and the drum shell 10 are placed in the container 36 with the boiling liquid 38 to heat the drum shell. The reheated drum shell 10 is transformed from a solid state to a malleable state and formed into a shape complementary to the mold 50 as shown. Reheating is continued for one to two minutes. Thus, the outer surface 48 of the drum shell 10 no longer has any striations on its outer surface and has a smooth shape that is pleasing to the consumer.

Referring to fig. 7, the drum shell 10 also has a support member 60, the support member 60 being positioned adjacent the outermost edge 56 of the drum shell 10. The support member 60 is preferably a resilient steel or metal member, but is less preferably any annular resilient member known in the art. The support member 60 is preferably spaced a predetermined distance from the outermost edge 56 of the drum shell 10. The support member 60 is preferably determined to reinforce the drum shell 10. The outermost edge 56 is preferably reheated to soften the outermost edge of the drum shell. Thereafter, the user presses the outermost edge 56 of the drum shell 10 inward to attach the support member 60 to the side of the outermost edge. Those skilled in the art will appreciate that the drum shell 10 has a memory such that when reheated, the drum shell will attempt to retract to its original shape. Thus, it is an unexpected advantage that upon reheating the drum shell 10 in the liquid 38, the drum shell 10 and all additional layers thereof will automatically bend around the support member 60 to form a support edge.

Referring to FIG. 8, the drum shell 10 has an "O" shaped wood member 62 disposed therein beneath the bearing member 60 for re-bending the outermost edge 56 and outer surface 48 of the drum shell 10 and for imparting one or more acoustic properties to the drum shell. As shown in fig. 8 to 10, the drum shell 10 is placed in the boiling liquid 38 in the container 36 and reheated for shaping the drum shell 10 around the wood member 62 as shown in fig. 10. Alternatively, the drum shell 10 is removed from the liquid 38 and the drum shell 10 is pressed against a flat surface while the plastic is still hot. Once flattened, the wood mold 62 is disassembled to be removed and the support member 60 is automatically retained within the drum shell 10 as shown. The drum shell 10 still has some inconsistencies at the top. Thus, optional grinding may be performed to flatten the drum shell 10 and ensure that all sharp edges are smooth. This is advantageous for the acoustic properties of the drum shell and the predetermined sound emanating therefrom. As shown, the drum shell 10 is bent into the desired shape by heating the shell 10 around the wood member 62 to create a high and clear slap when the drum head (not shown) is attached to the outermost end of the shell.

Referring now to FIG. 11, another preferred method of forming the drum 10 according to the present invention is shown. FIG. 11 shows an expanded PVC component 64 adjacent to an exemplary mold 66. The exemplary mold 66 of the present invention is collapsible as previously described and preferably has a body generally designated by the numeral 68 having a metal ring 70 attached to a top side 72 of the body. As described above, the mold 66 is made of any suitable material that can withstand being placed in a boiling liquid, such as in excess of one hundred degrees Fahrenheit. Preferably, the mold 66 is collapsible and is a metal, aluminum, stainless steel, treated metal, treated wood, thermoplastic, composite, or any combination thereof, as described above.

Referring now to fig. 12, the mold 66 is preferably inserted into the expanded PVC member 64 using a clamp, wrench or other tool 74. Referring to fig. 13, the combined collapsible mold 66 in the expanded PVC member 64 is placed in a heated liquid. The heated liquid is in the container 36, as described above. The heated liquid is preferably any suitable high temperature liquid (e.g., water, oil, or a mixture) to shape the stretched PVC member 64 around the mold 66. It will be appreciated by those skilled in the art that the stretched PVC member 64 is thereafter transformed into a malleable state and now does not have any jagged outer surface, but rather has a smooth outer surface 76 that is commercially aesthetically pleasing as shown in fig. 14. The tool 74 may be used to place the expanded PVC member 64 in the container 36 and remove it from the container 36 any desired number of times until the expanded PVC member 64 is in a malleable condition and thereby formed.

Fig. 14 shows the stretched PVC member 64 with the ring 70 disposed therein pulled from the container 36. Preferably, in the malleable condition of this embodiment, the ring 70 is permanently secured in the stretched PVC member 64 for support. Referring now to FIG. 15, there is shown a top side 72 of the stretched PVC component 64, the PVC component 64 having a ring 70 molded thereon or attached therein. A preferred feature of this embodiment is that the resulting drum 10 has a reinforced drum head end that is strong to withstand repeated use and to prevent any deformation thereof during playing of the drum and during transport thereof. Referring now to fig. 16, the method of forming the drum 10 also has the step of adding a reinforcement 78 to the stretched PVC member 64 having the rings 70 therein. The stiffener 78 has an additional or second PVC ring 80 connected to a circular base plate 82. Alternatively, the stiffeners 78 may be any other reinforcing component or other thermoplastic material known in the art for providing additional structure to the finished drum 10. In this embodiment, the reinforcement 78 is an additional layer of expanded polyvinyl chloride generally indicated by reference numeral 80 and is not limited to this structure. As shown, the stiffener 78 is preferably attached to a circular base plate 82 by two or more screws 84, and the base plate has holes 81 to allow attachment to another component to manipulate the base plate when heated. Preferably, the reinforcement 78 is wedged between two or more screws 84 disposed on opposite sides of the base plate 82, as shown. Referring to fig. 17, the base plate 82 has manipulating members 86 disposed on opposite top sides of the base plate 82, the manipulating members 86 serving to grasp the base plate and manipulate the reinforcing member 78 when desired.

Referring to fig. 17, the reinforcement 78 is an annular member that is smaller in diameter than the expanded PVC member 64 and that can fit within the PVC member. Preferably, the reinforcement 78 is placed on the top side 72 of the stretched PVC member 64 with a tool 74 when hot or by hand when cold. The manufacturer grasps the handling member 78 of the base plate 82 with the tool 74 and then places the reinforcement member 78 in the top side 72. The base plate 82 also has a cord 88 or retaining member for holding the stretched PVC member 64 in place relative to the reinforcement 78. Thereafter, referring to fig. 18, the reinforcement 78, the expanded PVC member 64 with the ring 70, is placed in the container 32 with the heated liquid therein.

Referring to fig. 19, the reinforcement 78 is transformed from a solid state to a malleable state by the heated liquid in the container 36, and the stretched PVC member 64 is also reheated to also be transformed from a solid state to a malleable state. Thus, as shown, the reinforcement 78 is connected to the stretched PVC member 64.

Referring to fig. 20, a reinforced PVC member 64 for forming the drum 10 from PVC members is shown. Referring to fig. 21, the base plate 82 shown in fig. 20 is then removed, and the expansion member 90 (which is the cross-member (in this non-limiting embodiment) connected to the mold 66 for manipulating the mold) is then likewise removed. Referring to fig. 22 and 23, the mold 66 is then disassembled and removed as previously described to form the completed drum 10. The drum 10 is then mounted with a skin, as is known in the art.

Referring now to fig. 24, another exemplary drum 10 is shown. One significant problem in the art is that the PVC member 64 or drum 10 as shown in fig. 24 may become malleable during transport or if left in the bed or truck for an extended period of time during a particularly hot summer day. Often, percussion instruments are often transported from one location to another. In this way, the drum 10 made of PVC parts 64 may heat up during transport to become malleable and thus deform, or otherwise lose its shape.

The drum 10 of the present invention corrects this known problem in the art. Preferably, the drum 10 has a carcass 94 or internal support structure made of non-deformable elastic members or members that protect and support the shape of the drum. The drum 10 in this embodiment has a stiffener 78 and a ring 70 attached to the drum 10. The drum 10 has a skeleton 94, the skeleton 94 having a plurality of side rails 96 each connected to the ring 70 on one side and to a second lower ring 98 on the opposite side. Each longitudinal bar 96 or second lower ring 98 is made of a resilient metal member that may be the same or different than ring 70. In a preferred embodiment as shown in fig. 20, the skeleton 94 has four longitudinal bars 96, each longitudinal bar 96 being vertically aligned in the drum 10 for support. It is critical that the rods 96 be made of a material sufficient to prevent deformation of the drum 10, and that the rods 96 be made with a minimum amount of this material so as not to adversely affect the acoustic properties of the drum 10.

Referring to fig. 25, an enlarged view of armature 94 with second lower ring 98 is shown. Preferably, the second lower ring 98 has a smaller diameter than the ring 70 shown in fig. 34 to complement the geometry of the drum 10. However, the second lower ring 98 may have any geometry known in the art to provide support to the side curved wall 100 of the drum 10.

It should be understood that the foregoing description is only illustrative of the invention. Numerous alternatives and modifications can be devised by those skilled in the art without departing from the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances. The preferred embodiments described with reference to the accompanying drawings are presented only to demonstrate certain embodiments of the invention. Other elements, steps, methods and techniques that are substantially the same as those described above and/or in the appended claims are also within the scope of the present invention.

Claims (6)

1. A percussion instrument, comprising:

a body made of polyvinyl chloride pipe, wherein a first portion has a first diameter and a second portion has a second diameter, the first diameter being greater than the second diameter, wherein the first portion is formed by heating to a malleable state in a boiling liquid and then expanding.

2. A drum, the drum comprising:

a body having a first portion and a second portion, the body being made of a polyvinyl chloride pipe, wherein the first portion has a first diameter and the second portion has a second diameter, the first diameter having a drum head attached thereto, the first diameter being greater than the second diameter, wherein the first portion is spherical and is formed by heating to a malleable state in a boiling liquid and then expanding, and wherein the second portion is integrally connected to the spherical first portion and forms a cylindrical integral seat.

3. A percussion instrument, comprising:

a skin; and

a body made of polyvinyl chloride pipe, wherein the body has at least one portion that is malleable, heated, stretched polyvinyl chloride, wherein the heated, stretched polyvinyl chloride is stretched in a direction, and wherein the direction is generally from an interior of the polyvinyl chloride pipe to an exterior of the polyvinyl chloride pipe.

4. A percussion instrument, comprising:

a body made of a thermo-reactive plastic tube, the body having a first portion having a first diameter and a second portion having a second diameter, the first diameter being greater than the second diameter, wherein the first portion is formed by heating to a malleable state in a boiling liquid and then expanding.

5. A drum, the drum comprising:

a body having a first portion and a second portion, the body being made of a thermo-reactive plastic tube, wherein the first portion has a first diameter and the second portion has a second diameter, the first diameter having a drum head attached thereto, the first diameter being larger than the second diameter, wherein the first portion is spherical and is formed by heating to a malleable state in a boiling liquid and then expanding, and wherein the second portion is integrally connected to the spherical first portion and forms a cylindrical integral seat.

6. A percussion instrument, comprising:

a skin; and

a body made of a thermo-reactive plastic tube, wherein the body has at least one portion that is a malleable, heated, expanded thermo-reactive plastic, wherein the heated, expanded thermo-reactive plastic is expanded in a direction, and wherein the direction is generally from an interior of the thermo-reactive plastic tube to an exterior of the thermo-reactive plastic tube.