BACKGROUND OF THE INVENTION

[0001] The original standard for scuba tanks was steel with capacities of 50 and 70 cubic feet of compressed air or mixed gasses. These tanks often developed corrosion problems, prompting the introduction of aluminum tanks and the phasing out of the older steel variety. The aluminum tanks are more problem free and are higher capacity (80 cubic feet) at 3,000 pounds of pressure.

[0002] With the increased use of lighter aluminum tanks in scuba diving came the problem of increased buoyancy caused by the depletion of air as it is consumed during a dive. Heavier, lower capacity steel tanks have enough extra weight to offset most of the increased buoyancy caused by air consumption.

[0003] To solve the problem of increased buoyancy, more weight is required to attain residual negative buoyancy with one's Buoyancy Control vest empty and air tank depleted to the point where it is time to surface. The extra weight cannot be carried by most weight belts, so it is usually carried in the forward pockets of the Buoyancy Control vest. This creates an excessive forward weighting imbalance that is made worse as tank buoyancy increases with air consumption. This forces the diver to fight the resulting forward pressure to achieve proper trim or position in the water, especially at the end of a dive when fatigue can make the face-down pressure a safety problem. Weights added to the pockets of a vest are not easily removed in an emergency.

[0004] Several devices have been used as tank weights to remedy the problem of excess tank buoyancy.

[0005] Weighted pouches and lead weights attached in various ways to belts strapped to the tank have been employed (U.S. Pat. No. 4,455,718 to Finnern). The disadvantages of this type system are that they tend to slip out of position after the webbing becomes saturated with water and expands and the pouches and solid weights are bulky with the weight unevenly distributed. One device is comprised of a web strap harness which can hold one ore more individual cylindrical weights in bandolier fashion. This system is not removable in a dive emergency and is subject to slippage with water saturation as well. It is also more expensive than other systems. Pouches for weights are also made to be threaded onto the tank retaining band. since the tank band is what secures the tank to the diver, it cannot be removed during a dive and the fact that many tank band widths and configurations exist precludes their use with many tank bands. These are also bulky with uneven weight distribution.

[0006] Lead weights in a flat ring shape are made to be put in a boot which is fitted onto the bottom of the tank (U.S. Pat. No. 5,788,475 to Henderson). This method requires two lead rings to achieve the optimum ballast weight of about four pounds and the necessarily tight fit of the boot makes it extremely inconvenient to transfer from one tank to another, necessitating the purchase of weights for each tank the diver owns (usually two or more). As a result of this configuration, one cannot ditch the weight during a dive emergency and the extra weight stays with the tanks, making them more cumbersome to handle. Another system uses a special tank boot with weights fitted into it with a retainer which can be pulled to release the weights (U.S. Pat. No. 6,030,146 to Nicolen, et al.). This has the disadvantages that the system is not easily transferred from one tank to another and the ring pull used to release the weights may be accidentally snagged, dropping the weights unexpectedly.

BRIEF SUMMARY OF THE INVENTION

[0007] This novel device provides a safer, more effective, easier to use trim weight system for attachment to a standard diameter scuba compressed air tank.

[0008] This invention incorporates several features which solve the problems posed by existing devices and systems designed as tank weighting to compensate for excess back buoyancy produced in aluminum tanks by the consumption of air during a dive.

[0009] With this device the “strap” and weighting functions are integrated by way of a curved stretchable tubing (such as rubber) filled with finely divided weight (such as lead shot) that is sealed flat on both ends to allow the attachment of a quick-release type buckle (preferably side-release).

[0010] This embodiment allows the device to be stretched enough to provide a snug, non-slip grip on any standard diameter scuba tank. The device is easily transferred from one tank to another and provides a low-profile distribution of the weight around the tank. The side release buckle prevents accidental release during a dive and provides for instant release in an emergency. The flat buckle and softness of the shot-filled tubing also allows it to function as a protective bumper and anti-roll device during transport.