Patent Publication Number: US-2021169062-A1

Title: Rodent gasser with self-ignition system and method of using the same

Description:
This application claims the priority of U.S. Provisional Application Ser. No. 62/477,492 filed Mar. 28, 2017, and also the priority of U.S. Provisional Application Ser. No. 62/539,146 filed Jul. 31, 2017. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention is related to the field of pest control and, more particularly, to a rodent gasser or smoke cartridge with a self ignition system that eliminates the need for a fuse. As referred to herein, the term “rodent” in intended to include at least gophers, pocket gophers, moles, ground squirrels, rats, skunks and woodchucks, as well as similar rodent-type pests. 
     Description of the Related Art 
     Smoke cartridges have traditionally been developed and used for signal and distress flares like those disclosed in U.S. Pat. No. 8,182,622 (“the &#39;622 patent”) and are typically ignited using a fuse. U.S. Pat. No. 5,917,142 (“the &#39;142 patent”) discloses an ignition system for a flare that relies upon frictional engagement between the head of the flare and a surface on the flare cap. Neither the &#39;622 patent nor the &#39;142 patent contemplate having any applicability to a rodent gasser device or method but, for the teaching that is set forth therein, both the &#39;622 patent and the &#39;142 patent are hereby incorporated by reference as if fully set forth herein in their entireties. 
     Pull wire igniters like that disclosed in U.S. Pat. No. 5,313,888 (“the &#39;888 patent”) have also been used for flares. However, the &#39;888 patent also does not contemplate any applicability to a rodent gasser. 
     Existing rodent gassers are ignited using a fuse, a method of operation that can have several problems. 
     First, the length of the fuse determines how long it burns. To keep fuse size reasonable, the burn times are typically 5-10 seconds before the gasser fully ignites the gaseous or gas-forming composition but, by this time, it is dangerous to still be holding onto the fuse. Hence, rodent gassers that are lit by a fuse require caution due to the risk of error in handling and resulting injury. 
     Second, as fuses are affected by the movement of air, the extended burn time before the gasser fully ignites can be additionally problematic in windy conditions. Also, fuses are affected by moisture which can also compromise their effectiveness. 
     Third, it is also a common problem for fuses used with gassers to become disconnected or damaged, thus making it impossible to ignite the gaseous or gas-forming composition in the rodent gasser cartridge. 
     Therefore, a need exists for a rodent gasser with a self ignition system that provides better protection for the consumer and, by not requiring a lighter, is easier to ignite. A need also exists for a rodent gasser that is more robust in both storage and use, and for a method of using a rodent gasser having a self-ignition system. 
     SUMMARY OF THE INVENTION 
     In view of the foregoing, the present invention is directed to a rodent gasser having a self-ignition system. The self ignition system has a prime load that can be adjusted and that can provide up to 15-60 seconds of time, and preferably about 30-45 seconds, before the gasser composition fully ignites, thus giving the consumer more time to safely place the gasser in the rodent&#39;s burrow and retreat a safe distance away. The ignition system is windproof and water proof, being protected by a plastic shroud built into the gasser itself. The present invention is further directed to a method of using a rodent gasser having a self-ignition system. 
     Accordingly, it is an object of the present invention to provide a rodent gasser having a self-ignition system that does not require or use a fuse to light the gasser, simplifying operation for the user. 
     Another object of the present invention is to provide a a rodent gasser having a self-ignition system in accordance with the preceding object that is unaffected by wind and/or by moisture and therefore will light with greater reliability. 
     A further object of the present invention is to provide a rodent gasser having a self-ignition system in accordance with the preceding objects that, as compared with fuse-lit gassers, has a longer burn time, on the order of up to about 60 seconds, before the actual formula in the smoke cartridge is ignited. 
     Yet another object of the present invention is to provide a rodent gasser having a self-ignition system in accordance with the preceding objects that has a plastic cap and, according to at least one embodiment, a plastic shroud that fully protects the gasser ignition elements when the rodent gasser is not in use. 
     Still another object of the present invention is to provide a rodent gasser having a self-ignition system in accordance with the preceding objects that is simple to understand and execute for the consumer. 
     A further object of the present invention is to provide a rodent gasser having a self-ignition system in accordance with the preceding objects that is robust and resistant to tampering and damage from shipping. 
     Another object of the present invention is to provide a method of using a rodent gasser having a self-ignition system of the type set forth in the preceding objects by which the user removes the cap from the gasser cartridge to reveal an ignition component, ignites the gasser cartridge, places the cartridge in a rodent burrow or other rodent lair and then retreats a safe distance away from the location where the rodent gasser was placed before the gaseous or gas-forming composition in the cartridge ignites to produce a pest fumigating gas or smoke. 
     Yet another object of the present invention is to provide a rodent gasser having a self-ignition system in accordance with the preceding object in which, according to a first embodiment, the step of igniting the gasser cartridge includes 1) removing the cap to reveal a strike pad in the plastic shroud, 2) further removing the shroud on the gas cartridge by pulling the same straight up to expose an ignition button positioned on the cartridge, and then 3) taking the shroud in one hand and striking the strike pad against the ignition button to ignite the button, igniting the cartridge without a fuse. 
     A further object of the present invention is to provide a rodent gasser having a self-ignition system in accordance with the object before the preceding object in which, according to a second embodiment, the step of igniting the gasser cartridge includes removing the cap to reveal a gripping element such as a finger ring attached to a connecting element which is coupled to an ignition system integrated within the gasser, the user igniting the gasser cartridge by pulling the gripping element to release or activate an igniting element such as a firing pin structure within the gasser. 
     These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded photographic view of the components of a rodent gasser in accordance with a first embodiment of the present invention. 
         FIG. 2  is a photograph showing an assembled view of the rodent gasser components shown in  FIG. 1 . 
         FIG. 3  is a flow chart of the method steps undertaken when using the rodent gasser as shown in  FIGS. 1 and 2 . 
         FIG. 4  is an exploded view of the components of a rodent gasser with an ignition system integrated into the gasser in accordance with a second embodiment of the present invention. 
         FIG. 4A  is a photograph of a rodent gasser like that depicted in  FIG. 4 . 
         FIG. 5  is a photograph showing an assembled view of the rodent gasser components shown in  FIG. 4A . 
         FIG. 6  is a flow chart of the method steps undertaken when using the rodent gasser as shown in  FIGS. 4, 4A and 5 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     It is to be understood that the embodiments described herein are disclosed by way of illustration only. It is not intended that the invention be limited in its scope to the details of construction and arrangement of components set forth in the following description or illustrated in the drawings. Also, in describing the preferred embodiments, specific terminology will be resorted to for the sake of clarity. It is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. 
     According to a first embodiment as shown in the exploded view of  FIG. 1  and the assembled view of  FIG. 2 , the present invention is directed to a rodent gasser generally designated by reference numeral  10 . The rodent gasser  10  includes a top plastic cap  12 , a lower plastic shroud  14  with a strike pad  16 , and a gasser cartridge  18 , which is preferably wrapped in paper, having an ignition button  20 . 
     When assembled, the plastic cap  12  covers the strike pad  16  and the ignition button is positioned under the lower shroud  14 . When the cap  12  is removed from the gasser cartridge  18 , the strike pad  16  is exposed. The strike pad  16  is preferably made out of a material similar to that of a match strike pad. 
     The present invention is also directed to a method of using a rodent gasser having an ignition system of the type described herein. Hence, in use according to the first embodiment, the consumer removes the cap  12 , exposing the strike pad  16 , and then removes the lower plastic shroud  14  by pulling it straight up and away from the cartridge  18 . To help prevent tampering, the lower shroud is made so that it takes a reasonable amount of force to remove it from its position on the cartridge  18 . 
     With the strike pad  16  exposed, the consumer takes the lower shroud  14  in one hand and then frictionally engages the surface of the strike pad against the exposed ignition button on the gasser cartridge  18 . This action is similar to that taken when lighting a match. The button immediately ignites and starts the countdown to actual ignition of the gas-forming composition in the gasser cartridge  18 . 
     The steps of the method of use are further set forth in the flow chart of  FIG. 3 . The user first removes the cap from the gasser cartridge to reveal the strike pad in the shroud, step  100 , and then removes the shroud on the gas cartridge by pulling the same straight up to expose the ignition button positioned on the cartridge, step  102 . The user then takes the shroud in one hand and the cartridge in the other, step  104 , and strikes the strike pad against the ignition button to ignite the button, step  106 . With the button ignited, the user places the cartridge in a rodent burrow or other rodent lair, step  108 , and then retreats a safe distance away from the location where the rodent gasser was placed before the gaseous or gas-forming composition in the cartridge ignites to produce a pest fumigating gas or smoke, step  110 . 
     According to a second embodiment as shown in the exploded view of  FIGS. 4 and 4A  and the assembled view of  FIG. 5 , the present invention is also directed to a rodent gasser generally designated by reference numeral  300 . The rodent gasser  300  includes a top plastic cap  312  covering an integrated pull pin ignition assembly generally designated by reference numeral  316 , and a gasser cartridge  318 . The gasser cartridge  318  is preferably wrapped in paper, plastic or other suitable material. The top  321  of the gasser  300  may be sealed in plastic to protect the gasser from the elements. 
     Removal of the cap  312  reveals a gripping element here embodied as a finger ring  323 . The finger ring  323  could be made of metal, plastic and the like, and other alternative embodiments could use a pull tab, a hooked element and the like. The gripping element is preferably coupled to a connecting element  325  that is attached to an ignition component, such as a firing pin structure, that is part of the integrated pull pin ignition system  316 . The connecting element may be a twisted or untwisted wire, a chain, a cable, a string and the like. Alternatively, a separate gripping element could be eliminated provided the connecting element is configured with a grippable portion. In the embodiment shown, the finger ring  323  and connecting element  325  are covered by the cap  312  when the gasser is assembled as shown in  FIG. 5 . 
     In use of the rodent gasser according to the second embodiment, the consumer removes the cap  312 , exposing the finger ring  323  and connecting element  325 . To ignite the cartridge  318  the user pulls on the finger ring  323  which, through the connection of the connecting element  325 , releases the firing pin (not shown) to ignite the gasser. The gasser may be provided with an internal fuse or other ignition element which is ignited by the action of pulling on the finger ring. Military use of pull pin technology for lighting grenades, pyrotechnics, demolitions and the like is described in the Army Field Manual 7-7, Appendix P, Section 5: Demolition. The M81 and M80 are military examples of fuse ignitors like those that may be used in the instant application. 
     The steps of the method of use according to the second embodiment are further set forth in the flow chart of  FIG. 6 . The user first removes the cap from the gasser cartridge to reveal the activation portion of the pull pin ignition system, step  400 . The user then takes the gasser cartridge in one hand and grasps the finger ring using a finger on the other hand, step  402 , and then pulls the finger ring to ignite the gasser, step  404 . With the gasser ignited, the user places the cartridge in a rodent burrow or other rodent lair, step  406 , and then retreats a safe distance away from the location where the rodent gasser was placed before the gaseous or gas-forming composition in the cartridge ignites to produce a pest fumigating gas or smoke, step  408 . 
     According to both embodiments, the gas-forming material in the gasser cartridge may be made with a composition which is based on the oxidizer sodium nitrate or potassium nitrate such as the formulations listed as preferred embodiments in the first table on the following page. The composition can alternatively use both sodium nitrate and potassium nitrate. The gaseous or gas forming composition can contain a wide variety of ingredients the quantities of which those skilled in the art would know could be adjusted in order to provide differing performance attributes. Changes in composition may also be made to alter the cost, burn rate, smoke production, flame production, fuel/oxidizer ratio, ease of ignition, or molten byproducts of the rodent gasser, among other attributes. Without being limited thereby, a list of representative materials/components, with typical ranges, that the gaseous or gas forming composition may include is provided in the second table on the following page. 
     The rodent gasser product according to the present invention does not require a lighter, is wind proof, moisture proof, fully protected when not in use and simple to understand. The burn time of between about 15 seconds and about 60 seconds prior to ignition of the formula in the cartridge improves safety in use and the gasser lights virtually every time, providing much greater reliability than is possible with conventional fuse-lit gasser products. 
     
       
         
           
               
            
               
                   
               
               
                 Preferred Embodiments 
               
            
           
           
               
               
               
               
               
               
            
               
                   
                 % By Weight 
                   
                 % By Weight 
                   
                 % By Weight 
               
               
                 Ingredient Name 
                 In Batch 
                 Ingredient Name 
                 In Batch 
                 Ingredient Name 
                 In Batch 
               
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 Sodium Nitrate 
                 50.40% 
                 Potassium Nitrate 
                 39.52% 
                 Potassium Nitrate 
                 45.14% 
               
               
                 Sulfur 
                 38.19% 
                 Sulfur 
                 38.99% 
                 Sulfur 
                 45.23% 
               
               
                 Charcoal/Carbon 
                 9.00% 
                 Charcoal/Carbon 
                 9.30% 
                 Charcoal/Carbon 
                 8.00% 
               
               
                 Mineral Oil 
                 2.41% 
                 Calcium Carbonate 
                 9.19% 
                 Dextrin 
                 1.63% 
               
               
                 Total 
                 100.00% 
                 Mineral Oil 
                 3.00% 
                 Total 
                 100.00% 
               
               
                   
                   
                 Total 
                 100.00% 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
               
             
               
                   
               
               
                   
                 Weight percentage 
               
               
                   
                 of gaseous or gas 
               
               
                 Material/Component 
                 forming composition 
               
               
                   
               
             
            
               
                 Potassium Nitrate and/or Sodium Nitrate 
                 30%-60%  
               
               
                 Sulfur 
                 0%-50% 
               
               
                 Carbon/Charcoal 
                 6%-30% 
               
               
                 Paraffin Wax 
                 0%-5%  
               
               
                 Oil (Paraffinic, Mineral, etc) 
                 0%-6%  
               
               
                 Water 
                 0%-6%  
               
               
                 Starch/Dextrins 
                 0%-10% 
               
               
                 Polyvinyl Chloride 
                 0%-10% 
               
               
                 Sawdust 
                 0%-10% 
               
               
                 Ground Rock/Mineral such as Talcum Powder, 
                 0%-20% 
               
               
                 Calcium Carbonate, Clay 
               
               
                 Sugar (sucrose, lactose, fructose, maltose, etc.) 
                 0%-20% 
               
               
                   
               
            
           
         
       
     
     The foregoing descriptions and drawings should be considered as illustrative only of the principles of the invention. The invention may be configured in a variety of shapes and sizes and is not limited by the dimensions of the preferred embodiments. Therefore, it is not desired to limit the invention to the specific examples disclosed. Rather, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.