Abstract:
A fireworks artillery shell for use as a consumer firework which may be propelled by the use of a mortar is provided which includes a casing, a lift charge, an effects charge, a timing fuse and an ignition fuse, and seals. The seals are provided within the casing above and below the effects charge to increase the burst effect of the effects charge. The lift charge is positioned within the casing and below the lower seal, and upon ignition, lifts the fireworks artillery shell into the air. The seals promote a harder break and more explosive effect from the effects charge without interfering with the lifting charge.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   This invention relates to a consumer fireworks shell which includes a lifting charge to propel the shell and an effect charge which provides a visual and audible display once the shell has been lifted. More particularly, it is concerned with a shell wherein the effect charge is tightly encased by the use of packing material to increase the explosive effect of the charge. 
   2. Description of the Prior Art 
   Fireworks have long provided entertainment to viewers by their colorful displays. As used herein, “fireworks” means “consumer fireworks” as defined in Title 27, Code of Federal Regulations, Section 55.11, as small fireworks devices designed to produce visible effects by combustion and comply with the construction, chemical composition, and other requirements of the U.S. Consumer Product Safety Commission, as set forth in Title 16, Code of Federal Regulations. 
   It is well known, for example, to have fireworks artillery shells which include a lifting charge and an effects charge. These artillery shells are placed in an upright tube, sometimes called a mortar (see, for example, U.S. Pat. No. 6,286,429, the disclosure of which is incorporated herein by reference). A typically prior art artillery shell is shown in FIG.  1 . The shell  10  has a long fuse  12  leading from the end of the tube down to the lift portion charge  14 . The lift portion  14  has a paper cylinder  16  wrapped around a black powder lift charge  18 . Ignition of the fuse  12  leads to ignition of the lift charge  18 , which propels the shell  10  upwardly and out of the tube. The shell  10  also typically includes a timing fuse  20  to connect the lift charge to an effects portion  22  having an effects charge  24 . As shown in  FIG. 1 , the effects portion  22  is typically provided by two paper cups  26  and  28  with a paper liner. The maker scoops the cups into a receptacle of the effects charge  24  and then pushes the two open ends of the cups together and glues the cups together. The connected cups are then wrapped in paper, and then connected to the timing fuse and lifting portion. This timing fuse  20  provides a suitable delay between the ignition of the lift charge  18  and the detonation of the effects charge  24  in order to allow the shell to reach a desired altitude. The timing fuse  20  then detonates the effects charge  24 , which then produces the visual effect. Another type of artillery shell is shown in U.S. Pat. No. 6,283,033 and D429,516, the disclosures of which are incorporated herein by reference. 
   However, because of the amount of explosives for such fireworks is limited by regulation, the bursting effect of such prior art artillery shells has been small, especially in relation to display fireworks. As such, there has developed a need for an artillery shell which has a greater bursting presentation while still within the consumer fireworks definitions and regulations, and which is still economical to produce and sell. 
   SUMMARY OF THE INVENTION 
   These objects have largely been met by the fireworks artillery shell of the present invention. The fireworks artillery shell herein remains a consumer firework with a limited amount of total explosive, but effectively increases the burst presentation of the shell by more effective sealing of the surrounding casing for the effects charge in using a paper tube with packing material pressed into place at each end. Consequently, the effects charge is held more tightly, and upon detonation, the effects are driven more effectively and with greater audible report than was possible with prior art fireworks artillery shells which do not have effective sealing using a dense, inert sealing material to seal off the effects charge from the lifting charge and to seal the effects charge within the casing. 
   In broad terms, the artillery shell of the present invention includes an ignition fuse, a casing, a lifting charge, a timing fuse, and an effects charge. The casing is preferably a cylinder with sealing material sealing the effects charge within the cylinder. Preferably, the sealing material is earth, and in particular clay, which is tamped and tightly packed into place to seal and isolate the effects charge. The cylinder is preferably a paper tube which is most preferably seamless. The clay sealing material is tamped by pressing or by impact to seal tightly against the cylinder. 
   Upon ignition of the effects charge by the timing fuse, the effects charge detonates. Because the cylinder is sealed by the packing material, leakage of the gases from the casing is minimized. Thus, the explosive effect of the effects charge is concentrated within the casing, which ruptures as the explosive gases escape. As a result, the audible report and distance the effect particles are propelled is increased in comparison to existing fireworks artillery shells. 
   These and other advantages will be readily apparent to those skilled in the art with reference to the drawings and description which follow. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a vertical cross sectional view of a prior art fireworks artillery shell, showing the casing surrounding the effects charge, the casing including two cups and a paper liner; and 
       FIG. 2  is a vertical cross sectional view of the fireworks artillery shell of the present invention, wherein the casing for the effects portion of the shell is a tubular member with plugs of sealing material at each end of the tube. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring now to  FIG. 2 , a fireworks artillery shell  100  in accordance with the present invention broadly includes an ignition fuse  102 , a casing  104 , a lift charge  106 , a timing fuse  108 , and an effects charge  110 . A paper wrapper  112  preferably envelopes the casing  104  to provide for the receipt of identifying indicia and limited moisture resistance. 
   In greater detail, the ignition fuse  102  is typically of twisted paper or fabric strands covered with black powder for promoting the ignition of the fuse and of a length sufficient to extend upwardly and over the top of the mortar. The length and coating may also be varied according to the desired delay between the time the remote end  112  of the fuse is lit and the time the lifting charge is ignited. 
   The casing  104  is preferably a paper cylinder which is most preferably manufactured as a seamless tube with a hole at its bottom end to permit the passage of one end of the ignition fuse  102  therein. The tube is most preferably solid paperboard stock, but alternatively may be manufactured by spiral wrapping of paper in successive layers, and additional paper or paper mache may be applied or glued to the exterior of the tube to increase its strength. 
   The lift charge  106  is conventional and may be of different compositions as desired by the maker. One suitable lift charge  106  for a consumer fireworks artillery shell  100  as disclosed herein would typically be between about 5 and 12 grams and more typically would be about 8 grams, and may be of a black powder charge or suitable alternatives, such as a composition by weight of about 74% potassium benzoate (KC 7 H 5 O 2 ), 6% sulfur (S), and 20 percent carbon (C), preferably charcoal. 
   The timing fuse  108  is also of twisted paper or fabric material coated with black powder or the like, and typically has a greater thickness than the ignition fuse. The timing fuse  108  operatively connects the lift charge  106  to the effects charge  110 , such that upon ignition of the lift charge  106 , the timing fuse  108  is lit and burns upwardly to ignite and detonate the effects charge  110 . 
   The effects charge  110  may have many different compositions as is well known to those skilled in the art. Illustrated herewith is an effects charge  110  having a bursting charge  114  and a plurality of pearl charges  116 , which, after ignition, present the appearance of colored streams or stars. A suitable bursting charge  114  for a consumer fireworks artillery shell in accordance with the present invention would typically weigh between about 5 to 11 grams and would typically be about 8 grams, and have a composition by weight of about 22% potassium perchlorate (KClO 4 ), 48% potassium nitrate (KNO 3 ), 26% carbon, typically charcoal (C), and 4% powder of polished gelatinous rice. The composition of the pearl charges  116 , which are typically small balls and present a colorful display when ignited, will vary according to color and are well known by those skilled in the art, but a typical effect might have a plurality of pearl charges which display a red color after ignition. A typical composition by weight for a red pearl charge  1116  would be 40% potassium perchlorate (KClO 4 ), 25% strontium carbonate (SrCO 3 ). 20% aluminum-magnesium powder alloy, 10% phenolic resin and 5% polyvinyl chloride. The pearl charges may also be colored blue, yellow, green, silver or other colors as is well known by those skilled in the art. 
   Sealing material  118  is provided within the casing  104  on top of and below the effects charge  110  as the fireworks artillery shell  10  is oriented in FIG.  2 . The sealing material  118  is relatively incombustible and preferably provided as a relatively dry clay powder which is tamped or compressed into place into plugs. An upper seal  120  of sealing material  118  is substantially solid and imperforate. A lower seal  122  of sealing material  118  is tamped or compressed around the timing fuse  106 , which passes through the lower seal  122  and extends above and below it to come in contact with the lift charge and the effects charge. Wafers  124  of paperboard are preferably positioned within the casing  104  above and below each of the seals  120  and  122  to help isolate the seals from moisture intrusion, inhibit fragmentation, and to aid in assembly. The casing  104 , being substantially continuous and imperforate in the area between the upper seal  120  and the lower seal  122 , has an upper end  126  and a lower end  128 . The upper seal  120  extends substantially across and encloses the upper end  126 , and the lifting charge extends substantially across the lower end  128 . 
   To construct the fireworks artillery shell  100  hereof, the maker places the wafer  124  atop the cylinder of the casing  104  and then inverts it and places the clay powder in the casing, then adds the wafer positioned below the upper seal  120 . The clay powder sealing material  118  is then compressed into place. One way of accomplishing this is by using a hammer and a tool with a shaft and a disc fitting into the casing. The disc of the tool has an outer diameter corresponding to the inner diameter of the casing. By several swift strokes of the hammer, the sealing material  118  is tightly packed and compressed into place against the casing  104  and, with the wafer  124  between, against the effects charge. The effects charge  10  is then placed in the casing  104  and the timing fuse  106  inserted into place. Another wafer  124  is placed in the casing, and the sealing material of the lower seal  122  is inserted into the casing, and then another wafer  124  placed atop the sealing material  118  so that wafers  124  are both above and below the lower seal  122 . The hammer and tool are used again as described above to compress the powder into a tight sealing arrangement with the casing  104  and compressed toward the effects charge with the wafer  124  in between, by several hammer strokes. The lift charge  104  is then filled into the bottom end of the casing  104  and pressed into place with the timing fuse  102  passing through the casing  104  as described above and one end thereof in communication with the lift charge  106  as described. In use, the fireworks artillery shell  100  is inserted into the mortar with the lifting charge positioned lowermost as illustrated and with the ignition fuse  102  leading upwardly and over the open upper end of the mortar. The user lights the exposed end of the ignition fuse  102 , retires a safe distance, and watches. The lift charge  106  burns through the paper wrapping  112  and propels the shell  100  out of the mortar and ignites the timing fuse  108 . When the timing fuse in turn ignites and detonates the effects charge  10 , the sealing material and casing causes and improved and more powerful explosion which more forcefully distributes the pearl charges. 
   It may be appreciated that various sealing materials may be employed in the present invention. For example polyurethane or other synthetic resins, glue, paste, or cement might be used instead of or in addition to the clay sealing material. Additionally, the casing might be provided of synthetic resin, such as polyvinyl chloride, instead of paper, paperboard or the like. The construction of the fireworks artillery shell  100  is simplified relative to existing shells, requiring only a single tube rather than multiple components. As a result, a simpler device is provided without significant changes in overall weight, while a stronger “break” when the effects charge is detonated is produced. 
   Although preferred forms of the invention have been described above, it is to be recognized that such disclosure is by way of illustration only, and should not be utilized in a limiting sense in interpreting the scope of the present invention. Obvious modifications to the exemplary embodiments, as hereinabove set forth, could be readily made by those skilled in the art without departing from the spirit of the present invention.