Patent Publication Number: US-8991316-B2

Title: Gas controlled delay timing device

Description:
This utility patent application is based on and claims the priority filing date of U.S. Provisional Patent Application No. 61/721,413, filed on Nov. 1, 2012. 
    
    
     Notice is given that the following patent document contains original material subject to copyright protection. The copyright owner has no objection to the facsimile or digital download reproduction of all or part of the patent document, but otherwise reserves all copyrights. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention pertains to delay timing devices, and more particularly to delay timing devices that can be easily adaptable, if desired, to adjust the time delay. 
     2. Description of the Related Art 
     Pressurized gas, smoke and percussion canisters are sometimes launched by riot police and military personnel into an area or building to force occupiers or protestors to leave the area or building. Sometimes, it is desirable to delay activation of the canister a few seconds after deploying it to prevent detection and to give the riot police and military personnel sufficient time to install face masks or to evacuate the target area. The desired time delay for activation of the canister may vary according to many factors, such as the nature of the gas composition in the canister, the location and distance the target area or location is from the launch location, the number of occupiers or protestors, the size and shape of the area or building, and urgency for occupiers or protestors to leave the area or building. 
     There are different manufacturers of gas canisters which use a top mounted plunger style, canister valve assembly that must be activated in order to release the gas contained inside the canister. Typically, the gas canisters are manually activated by a plunger and then thrown towards the desired target. When activated, the aerosol gas inside the canister is immediately released and completely dispersed in 2 to 10 seconds. As the canister is thrown, smoke or aerosol gas is released. Also, if the desired target area is far away from the launch site, a large portion of the smoke or aerosol gas may be dispersed prior to reaching the target area. 
     What is needed is a delay timing device that can be used with a standardized pressurized gas canister used by riot police and military personnel. Such a device should be simple to operate and use mechanical components controlled by pressurized gas and not mechanical springs, electrical components, or batteries. Such a device should be relatively small and compact, relatively inexpensive and can be selectively attached or detached to different canisters. The device should include a simple design that can be easily adjusted for different time delay periods. 
     SUMMARY OF THE INVENTION 
     Disclosed herein is a gas flow dependent delay timing device that selectively connects to a pressurized gas dispersal canister used in the prior art. The device includes a main body that selectively attaches over the top valve assembly on the canister. 
     The device&#39;s main body includes three stacked air chambers that control the release and flow of compressed air from one chamber into an adjacent chamber and eventually causes activation of the top valve assembly. The main body includes an upper opening with an external pressure activated plunger assembly mounted thereon. In the embodiment shown, the external pressure is created by a handle that the user manually forces inward. 
     The plunger assembly includes a closed first chamber filled with a compressed gas. The pressure of the compressed gas in the first chamber may be increased or decreased during manufacturing to decrease or increase the time delay respectively. Located inside the main body and adjacent to the first chamber is a lower second chamber normally exposed to atmospheric air. The plunger assembly includes a longitudinal movement activated valve which is forced inward and presses against a post which allows compressed air in the first chamber to flow and pressurize the second chamber. In the embodiment presented, an external handle is attached to an end cap that covers the first air valve used to fill the first chamber with compressed air. When the handle is pressed inward, the entire plunger assembly is pressed inward in the main body causing the compressed air to flow into the secondary chamber. 
     A locking means is provided that holds the plunger assembly in the activated position. In the embodiment show, the means for holding is a compression ring located on the inside surface of the main body which engages the plunger assembly. A means for sealing, such as an o-ring, is disposed around the outer surface of the plunger assembly and the inside surface of the main body which enables the second chamber to be pressurized upon activation of the timer. 
     Located inside the main body and below and adjacent to the second chamber is an intermediate strut. Formed on the opposite side of the intermediate strut is a partially sealed third chamber. At least one air conduit is formed on the intermediate strut so that when compressed gas flows into the second chamber it then flows into the third chamber. The size and number of air conduits in the intermediate strut may be adjusted by the manufacturer to control how quickly compressed air flows from the second chamber into the third chamber. Located inside the third chamber is a second plunger with a hollow stem. When the main body is longitudinally aligned and attached to the gas canister, the hollow stem on the second plunger partially extends into the canister&#39;s valve assembly but does not activate the valve assembly. 
     When sufficient compressed air enters the third chamber to force the plunger body inward, the hollow stem is forced into the canister causing the aerosol gas to flow quickly into the hollow stem and into a lower discharge chamber in the device&#39;s main body. The lower discharge chamber is located below the second plunger. Holes formed in the side of the main body surrounding the lower discharge chamber allow the aerosol gas to escape into the environment. 
     In summary, after the device is assembled, an external compressed air source is connected to an air valve attached to the plunger assembly. The first chamber is then filled with the desired amount of compressed air (40-150 psi). When the plunger assembly is manually forced inward, the compressed air in the first chamber is sequentially released and flows into the second chamber and then into the third chamber. The third chamber is divided into two stacked smaller chambers by a second plunger assembly. When sufficient force is exerted on the second plunger assembly, the second plunger assembly is forced inward forcing the hollow stem into the canister&#39;s valve assembly. Pressurized gas then travels into the lower discharge chamber and eventually dispersed through side openings in the main body to the environment. Thus, a simple mechanical time delay mechanism is provided for a canister that is relatively inexpensive and less prone to failure. Because the pressure of the gas in the canister is predetermined, the manufacturer can provide devices with different delay timings to allow the user to throw different canisters with the desired time delay. In some instances, the manufacturer can also change the diameters of the air conduits, the size and number of air conduits between the first, second, and third chambers, and the volumes of the first, second and third chambers, to adjust the time delay period. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a delayed release pressurized gas canister. 
         FIG. 2  is a sectional side elevational view of the delayed release pressurized gas canister shown in  FIG. 1 . 
         FIG. 3  is an exploded view of the delayed released pressurized gas canister. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT(S) 
     Disclosed herein is delay timing device  10  that selectively connects to a pressurized gas or smoke filled canister  100 . The device  10  is a small compact structure that selectively attaches to the top valve assembly  108  commonly used on the canister  100 . The canister  100  includes a closed bottle  102  with upper cap assembly  104 . Located inside the upper cap assembly  104  is the top valve assembly  108 , Formed on the outer surface of the upper cap assembly  104  are external threads  110 . The canister  100  is filled with a pressurized aerosol gas  112 . 
     The device  10  is designed to selectively attach to the upper cap assembly  104  on the canister  100 . The device  10  includes a cylindrical main body  12  with an upper opening and lower opening  14 . Mounted over the upper opening  13  is an external pressure activated first plunger assembly  20 . The first plunger assembly  20  includes a cylindrical inner body  22  configured to fit and move longitudinally a short distance inside the upper portion of the main body  12 . The first plunger assembly  20  also includes an inner cap  24  with a threaded neck  26 . Extending over the upper opening  13  is an outer cap  28  with internal threads  30  that connect to external threads  18  formed on the outside surface of the main body  12  near the upper opening  13 . During assembly, the outer cap  28  is placed over the upper opening and the threads  18  and  30  are engaged to hold the outer cap  28  in place on the main body  12 . The top surface of the inner body  22  includes a threaded neck  26  that attached to a T-shaped handle  38  that extends through a center bore formed on the outer cap  28 . Located inside the neck  26  is a first valve  27 . 
     As shown in  FIG. 3 , the inner body  22  is a closed structure with a first cavity  40  formed therein when the inner cap  24  is attached thereto. Extending downward from the lower surface of the inner body  22  is a second valve  42  with a cylindrical hollow neck with a coaxially aligned, activation pin  44  located therein. The end of the hollow neck is open and configured to receive post  56 . The activation pin  44  extends from the upper section of the secondary valve  44  to the space inside the hollow neck. When the plunger assembly  20  is pressed inward, the secondary valve  42  is forced towards the intermediate strut  54  and the post  56  extends into the hollow neck and presses against the activation pin  44 . The activation pin  44  is then forced outward and communicates with the first chamber  40  and allows compressed air  90  to flow into the secondary chamber  50 . 
     A compression ring  46  is located around the outer side wall of the inner body  22  and near the upper opening  13 . During use, the handle  38  is pressed inward which forces the inner body  22  inward on the main body  12 . The inner body  22  moves pass the compression ring  46  enabling it to snap into a locking position and prevent the upward movement of the inner body  22  in the main body  12  to its original location. 
     Also as shown in  FIG. 2 , located inside the main body  12  and below and adjacent to the second chamber  50  is an intermediate strut  54 . Formed on the strut  54  is a central, coaxially aligned support post  56 . As discussed above, when the first plunger assembly  20  is forced inward, the activation pin  44  presses against the support post  56  causing compressed air  90  in the first chamber  40  to be released into the second chamber  50 . 
     The intermediate strut  54  includes at least one air conduit  58  that communicates with a third chamber  60  located on the opposite side of the intermediate strut  54 . Located inside the third chamber  60  is a second plunger assembly  70  that divides the third chamber  60  into an upper filling chamber  64  and a lower discharge chamber  68 . The air conduit  58  allows compressed air  90  to pass with a restricted flow from the second chamber  50  into the upper filing chamber  64 . 
     The second plunger assembly  70  includes an upper plunger head  72  and a perpendicularly aligned hollow stem  76 . An O-ring  78  is disposed around the outer surface of the plunger head  76  to create an air tight seal between the plunger head  72  and the inside surface of the third chamber  60 . When the device  10  is initially attached to the canister  100  as shown in  FIGS. 1 and 2 , the stem  76  on the second plunger assembly  70  partially extends into the top valve assembly  108  but does not activate the top valve assembly  108 . 
     When sufficient compressed air  90  enters the upper filing chamber  64 , the plunger head  72  on the second plunger assembly  70  is forced inward that forces the hollow stem  76  into canister body  102 . When the distal end of the hollow stem  76  communicates with the pressurized aerosol gas, the aerosol gas flows quickly into the stem  76  and into the lower discharge chamber  68  located in the main body  12 . Holes  80  formed in the main body  12  surrounding the lower discharge chamber  68  allow the smoke or aerosol gas  112  to escape into the surrounding area. 
     In the embodiment presented herein, the canisters with ¼ inch diameter valves are used. The first chamber is filled with compressed gas between 40 and 150 psi. One air conduit is formed in the intermediate strut with a diameter of approximately 3/1000 inch in diameter. When the pressure of the compressed gas is 100 psi, release of the smoke or gas  112  from the device begins approximately 2 seconds after activation of the plunger handle. When the pressure of the compressed gas is 60 psi, release of the smoke or gas from the device begins approximately 10 seconds after activation of the plunger handle. 
     In summary, the release of compressed gas  90  from the first chamber  40  and its sequential flow from the first chamber  40  into the second chamber  50  and then into the upper filling chamber  64  and the exertion of pressure on the second plunger assembly  70  in the third chamber  60  creates a simple mechanical time delay mechanism that is relatively inexpensive and less prone to failure. By adjusting the pressure of the compressed air  90  in the first chamber  40  and the diameter of the air conduit  58  between the second and third chambers  50 ,  60 , respectively, the manufacturer can change the time delay. 
     In compliance with the statute, the invention described has been described in language more or less specific as to structural features. It should be understood however, that the invention is not limited to the specific features shown, since the means and construction shown, comprises the preferred embodiments for putting the invention into effect. The invention is therefore claimed in its forms or modifications within the legitimate and valid scope of the amended claims, appropriately interpreted under the doctrine of equivalents.