Patent Abstract:
The invention is BURROWING PEST CONTROL DEVICE, while mixing together oxygen and a flammable gas and injecting it into an underground burrow. The device includes the feature of being operated from a remote position, a vortex injection of the gases, and a device for generating a shockwave to propagate combustion throughout the stream of mixed gases.

Full Description:
FIELD OF THE INVENTION 
   The present invention generally relates to an apparatus for burrowing pest control, and more particularly to an apparatus for injecting flammable gas and oxygen into underground pest burrows for combustion and extermination of burrowing pests. 
   BACKGROUND OF THE INVENTION 
   Burrowing pests have been a problem for gardeners, ranchers, and farmers since time in immemorial. There have been many devices for the specific purpose of combating burrowing pests in their underground burrows including spring traps, jaw traps, spring spears, steel traps, poisons, and explosive devices. Eradicating burrowing pests is made more difficult because the pest burrow may be quite long with various entry points, underground chambers, and various escape routes. Poisonous gases have been utilized but this is dangerous to the operator and may involve such environmental impact as to make it impractical. 
   Explosive gases have also been injected into the system of burrows of burrowing animals. The use of explosive gases can be effective, but faces certain challenges. An applicator for injecting flammable gases into an underground burrow must cause the gas to penetrate deeply into the system of burrows for it to be effective. Usually, the flammable gas is a mixture of oxygen and a flammable gas and, at a certain distance from the injection point, the two gases can separate and the effectiveness of the combustion may become greatly reduced. Such a device also has to be very safe for the applicator so that there is no possibility of combustion around the applicator or of carrying the combustion into the device itself. 
   SUMMARY OF THE INVENTION 
   The present invention is a burrowing pest control device based on injecting a mixture of oxygen and a flammable gas into underground borrows. The device includes a valve assembly, a combustion assembly, an ignition assembly, an injector assembly, and a control panel assembly. The burrowing pest control device works by mixing oxygen and a flammable gas and injecting that mixture of gases into the hole of the burrowing pest, so that the mixture of gases penetrates some distance into the hole. At a selected time, the mixture of oxygen and flammable gas is ignited by the ignition assembly and the mixture combusts underground, thus eliminating the burrowing pest in the underground burrow. 
   The valve assembly includes a hose connection for an oxygen hose from a source of compressed oxygen. It also includes a hose connection for a hose supplying flammable gas from a flammable gas source. The flammable gas and the oxygen are connected from exterior sources to provide the burrowing pest control device with both of these gases. The valve assembly also includes an oxygen valve, which is configured to open and close a pathway for oxygen into the device of the invention. The flammable gas valve is also configured to open and close a pathway for flammable gas into the device. The functions of both of these valves can be combined into one valve, which controls the flow of both gases. The valve assembly also includes a valve controller which controls the oxygen valve and may also control the flammable gas valve. The oxygen and gas can be controlled by two separate valve controllers. 
   The combustion assembly includes a combustion chamber in which combustion of the mixture of oxygen and flammable gas is initiated. The device also includes an ignition assembly which includes a spark plug, a device for generating and sending energy for the spark to the spark plug, an ignition switch, and a radio receiver for receiving a signal from a remote location to initiate a spark. The ignition assembly includes a transmitter for remote detonation of the gases. 
   The device also includes an injection assembly, which includes an injection tube, which is adjacent to the combustion chamber, which directs the mixture of gases into an underground burrow. 
   The device also includes a control panel assembly, which includes a control panel and a remote transmitter, with the remote transmitter configured for remote operation of the device. In one configuration of the device the remote transmitter is able to control one or more valves, which allows oxygen and flammable gas to flow into the combustion chamber, as well as to control the initiation of the spark in the ignition assembly from a remote location. 
   The device can include a mixing tip, which creates a thorough mixing of the oxygen and flammable gas. The device can also include a nozzle tip in the injection tube, which contains a narrowing internal diameter followed by a gradually expanding internal diameter. This constricting flare in the passageway through which the mixture of gases flows is designed to impart a shockwave to the gas and oxygen as the gases are ignited. In one configuration of the mixing tip, the flow of oxygen can serve as an eductor to draw the appropriate flow of flammable gas into the oxygen stream, which contributes to thorough mixing. The mixing tip can further include a turbo tip, which is configured to impart a vortex, or a spiraling flow, to the mixture of gases as they enter the combustion chamber. When the gases pass from the combustion chamber they pass through a nozzle tip which has reduced diameter and directional vanes to further impart vortex flow to the mixture of gases. 
   In one configuration of the device, the valve assembly is contained in a valve housing with the combustion ignition and injector assemblies located in a device tip. In this configuration, the valve housing and the device tip are connected by conduits which contain a line for flammable gas, a line for oxygen, and a line which contains the electronics line to the ignition assembly. In this configuration, the valve housing is held in a spaced apart relation from the device tip and the two are joined by extended lines containing flammable gas conduit, oxygen conduit, and electronics line. 
   The device can also include a thermal switch in the combustion chamber for the purpose of cutting off the flow of gases when the temperature of the combustion chamber exceeds a pre-selected temperature. The device can further include a check valve in the combustion assembly for the purpose of preventing the gases in the combustion chamber from being ignited and from burning material coming from outside of the device itself. This can occur when gas has been injected and ignited into a section of burrow, and flammable material in the burrow is still being burned. Then, when gas begins to be injected into another opening into the same burrow system, it is possible for the gas to be ignited by the burning material in the burrow rather than from the spark plug. In that case, the flow of new gas would be cut off by the check valve or the thermal switch. 
   The panel assembly can further include a status board on which various parameters of the device can be displayed. This includes information about the status of the gas and oxygen valve, power to the unit, and the battery. 
   One embodiment of the device includes a configuration in which the oxygen and the flammable gas are not mixed together until the combustion chamber, which is adjacent to the nozzle tip. 
   One embodiment of the device includes structure such as a mixture tip and a turbo tip to induce a vortex flow into the device, coupled with a constriction in the exit line, which creates a shockwave of combustion in the mixture of gases. 
   The purpose of the foregoing Abstract is to enable the public, and especially the scientists, engineers, and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection, the nature and essence of the technical disclosure of the application. The Abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way. 
   Still other features and advantages of the present invention will become readily apparent to those skilled in this art from the following detailed description describing preferred embodiments of the invention, simply by way of illustration of the best mode contemplated by carrying out my invention. As will be realized, the invention is capable of modification in various obvious respects all without departing from the invention. Accordingly, the drawings and description of the preferred embodiments are to be regarded as illustrative in nature, and not as restrictive in nature. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a cross sectional view of the device of the invention. 
       FIG. 2  is a view of the control panel of the invention. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   While the invention is susceptible of various modifications and alternative constructions, certain illustrated embodiments thereof have been shown in the drawings and will be described below in detail. It should be understood, however, that there is intention to limit the invention to the specific form disclosed, but, on the contrary, the invention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention as defined in the claims. 
   The preferred embodiment of the invention is shown in the figures.  FIG. 1  shows the burrowing pest control device  10  of the invention which includes a valve housing  12 , a device tip  14 , a handle  16  for carrying the device. The device is generally divided into a valve assembly  50  which is located within the valve housing  12 . Another division is the combustion assembly  52  which is located within the device tip  14 . The injector assembly  54  is also located in the device tip  14  and includes an injection tube  34  and a nozzle tip  76 . In this embodiment of the invention, device tip  14  is held in a spaced apart relationship from the valve housing  12 , and the two are connected by pipes. An oxygen pipe  18  transfers oxygen from the valve housing  12  into the metering and mixing region of the device tip  14 . A flammable gas pipe  20  conducts a flammable gas from the valve housing  12  to the metering and mixing region of the device tip  14 . A third pipe may also be present which houses wires and other electrical components for sending a signal from the valve housing  12  to the device tip  14 . 
   The valve housing  12  is preferably made of metal, but other materials can be utilized such as a suitable plastic, fiberglass or other material. The gas lines  18  and  20  are preferably made of metal pipe and may be approximately 24 inches long and ½ inch in diameter. 
     FIG. 1  shows a pipe clamp  22  and a pipe seal  40  which are devices utilized with the gas pipes  18  and  20 . The combustion assembly is shown as  52  and is located in the device tip  14 . The combustion assembly  52  includes a combustion chamber  66  and an oxygen conduit or pipe  18  and a flammable gas conduit or pipe  20 . An ignition assembly includes a spark generator  68  and a spark plug  24 , an ignition switch  70 , a valve controller  96 , and a radio receiver  72 . The spark plug  24  is preferably housed in a spark plug sleeve  26 . The spark plug  24  is electrically connected to the spark generator  68  by an electronics line  100 , and to an ignition switch  70 , as well as ignition control mechanisms in the valve housing  12 , which may be activated from the control panel  74  or from the remote transmitter  44 . A factory-set timed activation switch may also be added. A preferred design of the mixing tip  36  is one in which the flow of oxygen can serve as an eductor  85 , to draw the appropriate flow of flammable gas into the oxygen stream, which contributes to thorough mixing. 
   Located in the device tip  14  is also a thermal switch  28 , and a check valve  30 . The thermal switch  28  detects the temperature in the combustion chamber  66  and shuts off the flow of gases if the temperature in the combustion chamber exceeds a preset temperature. The temperature in the combustion chamber could exceed a preset temperature if gas has been ignited and dispensed for a period of time sufficient for the injection tube  34  to become hot. 
   The device tip  14  also includes a check valve  30 . When activated, the check valve  30  prevents the propagation of flame from the combustion chamber or the device tip  14  into the gas line  18  or  20 . 
   The device can be sized according to the requirements of the particular application, but one advantageous configuration is one in which the injection nozzle tube is made of non-ferrous metal and is a tube approximately 2 inches in diameter. 
   Sequentially, a valve controller  96  is activated by a controller valve activation switch  102 . The valve controller  96  opens the oxygen valve  46  and the flammable gas valve  48 , and gases flow toward the mixing tip  36 . The gases are mixed in the mixing tip  36 , which encloses the eductor  85 . From the mixing tip  36  the gases flow through a check valve  30  which prevents backflow. From the check valve  30  the mixed gases enter the combustion chamber  66  through a turbo tip which disperses the mixed gases in multiple directions into the combustion chamber  66 . From the combustion chamber, the gases flow through a nozzle tip  76  in which is located a vortex generator  32 . The vortex generator  32  imparts a swirling motion to the gases by use of directional vanes  106 . The directional vanes  106  impart a swirling motion into the mixture of gases coming from the combustion chamber  66  and exiting the nozzle tip  76 . The swirling of the gases creates a vortex effect which extends not only out the device tip as the gases exit the device, but also extends into the combustion chamber and serves to draw the two gases towards the exit of the device tip and to mix them together when in the swirling vortex. The vortex generator  32 , by creating a vortex in the gases, serves to mix the two gases together better and, since the vortex extends into the burrow, the two gases stay mixed together longer, and the stream of flammable gas and oxygen mixing together in a vortex extends for a greatly enhanced distance into the burrow. The vortex also serves to keep the two gases from separating as the distance from the device tip becomes greater. The nozzle tip  76  preferably includes a constricting flare  78 , which is a section in the tubing of the nozzle tip  76  which has a narrowing internal diameter followed by a gradually expanding internal diameter. This constricting flare  78  in the passageway through which the mixture of gases flows is designed to impart a shockwave to the gas and oxygen as the gases are ignited. 
   Within the valve housing  12  is located a valve controller  96 , an oxygen valve  36 , and a gas valve  48 . Within the valve housing  12  is also located a radio receiver  72  for receiving a signal from the remote transmitter  44 . From the remote transmitter  44  a signal can be received to begin the flow of gases and a separate signal can be sent to activate the ignition of the gases. When the gases have flowed for a sufficient time, a signal to ignite is sent from the remote transmitter  44 . The radio receiver sends that signal to the spark generator  68 , which uses the battery  80  to generate a spark at the spark plug  24 . 
   On the valve housing  12  is located a gas line connection  82  and an oxygen line connection  84 . To these connections are attached an oxygen hose  62  and a gas hose  64  which connect the device to an oxygen source  58  and a gas source  60 . 
     FIG. 2  shows the configuration of the control panel assembly  56 . The control panel assembly  56  includes a control panel  74 , with a unit off/on switch  94  for turning the unit on or off. Also shown on the control panel  74  is a gas line connection  82  and an oxygen line connection  84  for manually attaching the gas and oxygen line. The control panel  74  can include a power indicator  86  in the form of a light, which would indicate if the power to the unit is activated or not. A flow indicator  88 , battery indicator  90 , and a spark indicator  92 , may also be present and form a status board  104  as part of the control panel  74 . 
   In the following description and in the figures, like elements are identified with like reference numerals. The use of “or” indicates a non-exclusive alternative without limitation unless otherwise noted. The use of “including” means “including, but not limited to,” unless otherwise noted. 
   While there is shown and described the present preferred embodiment of the invention, it is to be distinctly understood that this invention is not limited thereto, but may be variously embodied to practice within the scope of the following claims. From the foregoing description, it will be apparent that various changes may be made without departing from the spirit and scope of the invention as defined by the following claims.

Technology Classification (CPC): 0