Abstract:
A tankless secondary air supply system to be used in an emergency situation during underwater diving is disclosed. Specifically, the present invention is a high pressure hose reserve air supply for underwater diving. The system is configured with a secondary hose separately connected to the main air tank. The secondary hose is of larger than customary bore and is made of flexible reinforced material in order to store reserve air when filled with pressurized air from the main tank. The hose is connected to the main tank with a check valve which permits the air from the main tank to automatically fill the hose immediately upon connection via the first stage regulator. The check valve maintains the high pressure air supply within the hose. The air which is stored in the hose serves as a secondary source of air during an emergency situation via a secondary regulator mouthpiece.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates generally to improvements in air supply for underwater diving. Specifically, the present invention relates to a high pressure hose reserve air supply for underwater diving. 
         [0003]    2. Description of the Related Art 
         [0004]    In an underwater diving emergency, such as depletion of the diver&#39;s primary air supply, divers need an alternate air source in order to make a normal ascent. The redundant air supply systems currently in use are auxiliary tanks (also known as pony tanks). These tanks are small, independently filled diving cylinders that provide a totally independent source of breathing gas for the diver in an emergency. When used with a typical scuba diving configuration, an auxiliary tank delivers ample air to enable the diver to execute a controlled ascent from an out of gas incident. The pony tank has its own independent diving regulator with first and second stages and often a submersible pressure gauge. The pony tank is a requirement for a solo diver with no alternate air source from a companion diver&#39;s tank and octopus regulator. 
         [0005]    However, this auxiliary tank has significant disadvantages including weight and size. The pony tank also requires additional baggage fees, cost and time for filling of the tank at the diving destination, as well as the cost and time for proper maintenance. It is very important that the pony tank be adequately maintained with regular hydrostatic testing and visual inspection procedures. The pony tank is an emergency device and pre-dive safety testing must be performed to ensure that it is ready for use. 
         [0006]    Thus, the auxiliary tank of the current state of the art requires significant effort and expense to transport and maintain. What is needed is a device which provides ample air to execute a controlled ascent from an out of gas incident at a much reduced cost and significantly greater convenience. It would be less expensive and much more convenient to have a device that was tankless and therefore did not require hydrostatic testing or visual inspection procedures. It would also be advantageous to have an integrated device that did not require additional equipment and that was self-filling, always on, and always ready to go. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention discloses a tankless secondary air supply system to be used in an emergency situation during underwater diving. Specifically, the present invention is a high pressure hose reserve air supply for underwater diving. The system is configured with a secondary hose separately connected to the main air tank. The secondary hose is of larger than customary bore and is made of flexible reinforced material in order to store reserve air when filled with pressurized air from the main tank. The hose is connected to the main tank with a check valve which permits the air from the main tank to automatically fill the hose immediately upon connection via the first stage regulator. The check valve maintains the high pressure air supply within the hose. The air which is stored in the hose serves as a secondary source of air during an emergency situation via a secondary regulator mouthpiece. The secondary hose is not additional equipment but rather takes the place of the alternate breathing air hose and alternate second stage regulator and mouthpiece which are part of the standard air supply system for underwater diving. The emergency air supply system of the present invention improves ease of use and enhances diver safety. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a partially schematic plan view of a standard air supply system for underwater diving in the prior art. 
           [0009]      FIG. 2  is a partially schematic plan view of an alternate prior art air supply system for underwater diving incorporating a backup tank air supply. 
           [0010]      FIG. 3  is a partially schematic plan view of the air supply system for underwater diving of the present invention, incorporating a backup air supply. 
           [0011]      FIG. 4A  is a schematic block diagram of the air supply system for underwater diving (scuba diving) of the present invention, incorporating a backup air supply, prior to the attachment of a full primary tank. 
           [0012]      FIG. 4B  is a schematic block diagram of the air supply system for underwater diving (scuba diving) of the present invention, incorporating a backup air supply, after attachment of a full primary tank and during use of the primary tank for underwater breathing. 
           [0013]      FIG. 4C  is a schematic block diagram of the air supply system for underwater diving (scuba diving) of the present invention, incorporating a backup air supply, after the primary tank has been emptied and during use of the reserve high pressure hose reservoir for underwater breathing. 
           [0014]      FIG. 5A  is a partially schematic plan view of an alternate embodiment of the air supply system that includes a T-connector off of the single high pressure port. 
           [0015]      FIG. 5B  is a partially schematic plan view of an alternate embodiment of the air supply system that includes a DIN tank attachment and quick connect to a high pressure port. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0016]    Reference is made first to  FIG. 1  which illustrates a partially schematic (not to scale) plan view of a standard air supply system  10  for underwater diving of the prior art. As shown in  FIG. 1 , the scuba diving air supply system  10  includes an air supply tank, regulators, hoses, and pressure gauge. Air supply tank  12  is connected to tank valve  14 . The tank valve  14  is connected to the first stage regulator  16  during use. First stage regulator  16  is connected to four hoses. These include: tank pressure hose (high pressure)  22 , buoyancy compensation device (BCD) air hose (low pressure)  30 , primary breathing air hose (low pressure)  18 , and alternate breathing air hose (low pressure)  26 . Tank pressure hose  22  is connected to the tank pressure gauge (psi)  24 . Buoyancy compensation device air hose  30  is connected to a stop valve BCD connector  32 . Primary breathing air hose  18  is connected to primary second stage regulator and mouthpiece  20 . Alternate breathing air hose  26  is connected to alternate second stage regulator and mouthpiece  28 . 
         [0017]      FIG. 2  provides a partially schematic plan view of an alternate prior art air supply system  10  for underwater diving incorporating a backup tank air supply. Tank valve  14  of primary air supply tank  12  is connected to the first stage regulator  16  during use. When a backup tank air supply is used, primary breathing air hose  34  is attached to a switch valve  38 . Switch valve  38  is connected to reserve tank air hose  40  (low pressure) which is attached to the reserve tank valve  44  (with integrated regulator) and the reserve air supply tank  42 . In case of an emergency situation due to depletion of the diver&#39;s primary air supply tank  12 , the diver will turn the switch valve  38  to close the flow communication with primary air supply tank  12  and access the air supply from reserve air supply tank  42  through reserve tank air hose  40  via the primary second stage regulator and mouthpiece  36 . 
         [0018]    Reference is next made to  FIG. 3  which discloses a partial schematic (not to scale) plan view of the air supply system  50  for underwater diving of the present invention, incorporating a backup air supply. In  FIG. 3 , air supply tank  52  is connected to the first stage regulator  56  via tank valve  54 . Tank pressure hose  62  is connected to the tank pressure gauge (psi)  64 . Buoyancy compensation device air hose  70  is connected to a stop valve BCD connector  72 . Primary breathing air hose  58  is connected to primary second stage regulator and mouthpiece  60 . The present invention discloses a unique reserve air supply system wherein a reserve air supply autofill check valve  74  is connected to the high pressure side of the first stage regulator  56 . Two high pressure ports are standard on higher end first stage regulators. Lower end first stage regulators have only one port. These lower end first stage regulators require an adaptor to run the tank pressure gauge and the reserve air supply autofill check valve  74 . These adaptors are readily available. A high pressure reserve air supply reservoir hose  66  is attached to the reserve air supply autofill check valve  74 . The reservoir hose  66  is of larger than customary bore and is made of flexible reinforced material similar to current high pressure scuba hoses in order to store reserve air when filled with pressurized air from the primary tank. For example, the reserve air supply hose would be constructed of rubber or alternately would have a polyester braided outer layer over a woven Kevlar inner layer. The hose would preferably have a maximum working pressure of 5000 psi and a minimum burst pressure of 20,000 psi with an internal diameter of ½ to 1 inch and a length of 60-70 inches. 
         [0019]    The surface consumption rate for a diver is about 12 psi per minute. The reserve air supply hose of the present invention would be approximately 60-70 inches long and have a ½ 1 inch internal diameter. Within these parameters, the ½ inch internal diameter hose would yield between 4.5 to 5.3 minutes at 1 atm and 1.1 to 1.3 minutes at 4 atm. A 1 inch internal diameter hose would yield between 9.3 to 10.9 minutes at 1 atm and 2.3 to 2.7 minutes at 4 atm. 
         [0020]    The other end of the high pressure reserve air supply reservoir hose  66  is connected to a reserve air supply pressure gauge (psi)  76 , which is attached to an alternate/reserve second stage regulator (high pressure) and mouthpiece  68 . High pressure reserve air supply reservoir hose  66  takes the place of the alternate breathing air hose (low pressure)  26  in  FIG. 2 . High pressure reservoir hose  66  provides access and serves as the reservoir for the backup air supply. The elements  38  (switch valve),  40  (reserve tank air hose—low pressure),  44  (reserve tank valve with integrated regulator), and  42  (reserve air supply tank) of  FIG. 2  are no longer necessary in the configuration of the present invention. 
         [0021]    In an alternate embodiment, there would be a quick connect to a High Pressure Port on the tank valve itself. This embodiment would require a change in the tank valve and would not be integrated into the regulator system. In another alternate embodiment, a T connector off of the single high pressure port typically found on low end first stage regulators could be utilized to connect to the tank pressure hose in the first instance and the check valve and reserve air supply hose in the second instance. 
         [0022]      FIGS. 4A, 4B, and 4C  illustrate the pressure within the air supply system of the present invention before attachment of the primary tank, during use of the primary tank, and after the primary tank has been emptied and the reserve air supply of the present invention is in use. To further illustrate the flow communications within these figures, the high pressure areas are shown in bold, low pressure areas are shaded grey, and unpressurized areas are unshaded. 
         [0023]      FIG. 4A  discloses a schematic block diagram of the air supply system for underwater diving of the present invention, incorporating a backup air supply, prior to the attachment of a full primary tank. At this point, the primary tank is full and has an approximate air pressure of 3000 psi. The hoses within the system have not been filled with air from the primary tank and are not pressurized. 
         [0024]    Continuing in  FIG. 4B , is a schematic block diagram of the air supply system for underwater diving of the present invention, incorporating a backup air supply, after attachment of a full primary tank and during use of the primary tank for underwater breathing. Once the primary tank is connected to the first stage regulator, the pressure in the primary tank fills the tank pressure hose (high pressure) as well as the low pressure (about 145 psi) primary breathing air hose and the low pressure buoyancy compensation device air hose. Importantly, the high pressure from the primary tank also travels through the check valve to fill the reserve air supply reservoir hose. This provides 9.6 minutes of breathable air supply for the average diver. When the reserve air supply reservoir hose is fully pressurized, the check valve closes and the emergency air supply remains available for use if necessary. 
         [0025]      FIG. 4C , provides a schematic block diagram of the air supply system for underwater diving of the present invention, incorporating a backup air supply, after the primary tank has been emptied and during use of the reserve high pressure hose reservoir for underwater breathing. In  FIG. 4C , the air pressure to the tank pressure gauge, the buoyancy compensation device, and the second stage regulator is gone. Under such emergency conditions, the high pressure reserve air supply reservoir hose is put to use. Utilizing the high pressure alternate/reserve second stage demand regulator and the reserve air supply pressure gauge, the diver is able access the reserve air supply contained in the high pressure hose reservoir and execute a controlled ascent from an out of gas incident. 
         [0026]      FIGS. 5A and 5B  disclose alternate embodiments of the present invention. In  FIG. 5A , a T-connector is positioned off of the single high pressure port typically found on low end first stage regulators. In this configuration, the in-flow connection of T-connector  75  is attached to the first stage regulator  56 . The two out-flow connections of T-connector  75  are attached to the tank pressure hose  62  and the autofill check valve  74 . The air supply reservoir hose  66  is connected to the autofill check valve  74 . The primary breathing air hose  58  and the buoyancy compensation device air hose  70  are connected to the two low pressure ports on the first stage regulator  56 . 
         [0027]    The alternate embodiment of the present invention shown in  FIG. 5B  requires the use of a DIN tank attachment rather than a yoke attachment.  FIG. 5B  discloses a quick connect to a high pressure port on the tank valve itself.  FIG. 5B  illustrates air supply tank  52  with tank valve knob  55  and tank valve  54 . Tank valve  54  has a DIN-type connector. T-connector  77  is connected to the DIN-type connector of tank valve  54 . The two out-flow connections of T-connector  77  are attached to autofill check valve  74  and DIN-type first stage regulator and connector  57 . The air supply reservoir hose  66  is connected to the autofill check valve  74 . 
         [0028]    Changes in the precise embodiments of the invention herein disclosed can be made within the scope of what is claimed without departing from the spirit of the invention. Other designs may be evident to those skilled in the art upon viewing this device. Although the present invention has been described in conjunction with the preferred embodiment, those skilled in the art will recognize modifications to this embodiment that still fall within the spirit and scope of the present invention.