Abstract: An improved second stage regulator employs a pneumatically-activated anti-set poppet and inhalation resistance adjustment control knob accessible externally of the regulator. The anti-set poppet utilizes a pressure-activated compression spring to seal the air inlet during exhalation. When the regulator is stored, the relaxed spring permits the seal to withdraw from the sharp edge orifice of the air inlet thereby avoiding seal wear which would otherwise diminish the performance of the regulator. The adjustment control knob permits the diver to modify the required cracking effort by changing the amount of spring compression when the regulator is pressurized.

Abstract: A diver's buoyancy compensator that allows greater design freedom in the placement of the air-containing buoyancy chambers to better suit the needs of the diver. A preferred embodiment of the invention comprises four distinct surfaces, two of which make up the two halves of a floatation chamber that provides primarily back mounted floatation and the other two of which provide the chamber for more forward front mounted floatation under the arms and over the shoulder. After the two halves of each such chamber are joined to one another, the chambers are joined to each other with interchamber passageways providing free passage of air into both bladder chambers, whereby inflation and deflation in both chambers occur substantially simultaneously through a single valve or hose which may be connected to either such chamber.

Abstract: A snorkel top device which may be readily added to an existing snorkel tube for preventing the inadvertent entry of splash water into the top of the tube by providing a flap which tends to deflect splash water so that it exits the snorkel top device without entering the tube attached thereto. The most significant feature of the invention is that the snorkel top device provides a simple and effective guard against entry of splashed water into the top of the snorkel tube and yet constitutes a unitary, relatively inexpensive structure which has no moving parts, no valves and which provides an aesthetically pleasing addition to existing snorkel tubes.

Abstract: A first stage scuba regulator wherein the intermediate pressure to the second stage regulator increases as tank supply pressure decreases, thus solving the problem of the sensitive second stage at the start of the dive and decreasing the cracking efforts and improving low pressure flow rates at lower tank pressures. The design employed in the present invention for creating an intermediate pressure inversion relies on undersizing the critical balancing shaft of the piston where high pressure air entering from the tank is neutralized between the high pressure O-ring and plastic high pressure seat. By reducing the effective area of a shaft under the O-ring, but in front of the sharp end of the piston, an imbalance is created. This imbalance is in the forward or closing direction of the piston shaft. This extra force decreases the load requirement of the spring and lowers the intermediate pressure at the high supply pressure.

Abstract: The present invention comprises an oil-filled depth gauge which is made far less sensitive to violent shock and the potential resulting inaccuracies to the maximum depth gauge indicator from such shock. More specifically, the present invention comprises an improved oil-filled scuba diving depth gauge in which the improvement provides a fluid dam member which may be affixed to or molded into the transparent enclosure covering the dial face to effectively block the flow of the oil in the region of the gauge occupied by the maximum depth indicator dial. The fluid dam reduces the likelihood that a sudden jar or other violent shock will induce a relative differential in the motion between the oil and the gauge body which might otherwise produce inaccuracies in the position of the maximum depth indicator dial.

Abstract: A vest of the type having an inflatable bladder providing selectable degrees of buoyancy, such as for snorkeling. The vest comprises an elastic upper body garment for encircling the chest and back of the user and an airtight inflatable bladder, secured at discrete locations to the chest-covering region of the garment by at least a pair of elastic straps for limited movement relative to the garment. The bladder is substantially flat against the garment when deflated and is free to move relative to the garment while being inflated. Attachment of the bladder to the underlying garment is provided by means of a plurality of elastic straps which permits the relative movement of the bladder and the underlying vest-shaped garment. As a result, inflation of the bladder has little or no effect upon the fit of the underlying garment on the user. Attachment of the bladder and the underlying vest-shaped garment is also provided by an area of Velcro fasteners on the mating surfaces of the bladder and underlying garment.

Abstract: An integral floatation or buoyancy compensating device and weight assemblies for divers. The buoyancy compensating device provides an integral back pack which is used to support the air tank of a conventional scuba diving type. At least one and preferably two quick release weights are mechanically attached to the buoyancy compensating device usually at an integral waistband and worn around the waist similar to conventional hip style weights, but are individually releasable by a quick release mechanism from the waistband rather than normally jettisoning an entire band. The band to which the weights are attached are an integral lower extension of the buoyancy compensator or buoyancy compensating device. Weight release is simple and one handed with no band to entangle or become entrapped beneath the tank or other piece of equipment normally worn by the diver. Weight location is set about the waist near the hands when in a relaxed position. Weight release is effected by a simple grasping and squeezing action.

Abstract: An improved breathing regulator for a scuba diver comprises an integrated exhaust assembly having as the only removable part thereof a fastened cover for gaining access to the exhaust valve. The housing and integrated exhaust assembly reduce the cost of manufacture and increase the reliability and safety of the breathing regulator by obviating the prior art detachable exhaust tee.

Abstract: An improved hydrodynamic swim fin utilizes a wing and a tail that are overlapped normally to provide a two-stage propulsion system. Ribs support the wing and tail and define flow channels. These ribs are parallel to each other and to the longitudinal axis of the fin whereby the effective area through which flow proceeds is uniform throughout the length of the fin. No parts of the ribs form barriers to the leading edges of the side wing segments whereby laminar flow is achieved. The fin part is maintained essentially rigid; however, the fin part is allowed limited angular movement about a defined transverse axis to achieve proper attack angle. Since the fin part is rigid, it maintains that attack angle throughout the length of the fin part. Trailing ends of the wing are individually flexible to produce greater opening for two-stage propulsion during the power downstroke, and to produce substantial closure for one-stage propulsion during the upstroke.

Abstract: A diaphragm for a scuba diving regulator incorporates a contact member in the form of an axially thin spool cast or fabricated of low friction material. The contact member is installed at a central aperture of the diaphragm so that the end plates or flanges of the spool closely encompass the diaphragm on opposite sides. One of the flanges is located on the outside of the diaphragm, and the other is located on the inside, to be engaged by the actuating lever of the demand valve. No special sealing means need be provided about the spool, since the pressure difference between the ambient water and the air in the breathing chamber is always small, whatever be the depth of the diver in the water, but effective to maintain the seal.

Abstract: Affixed to the back plate on opposite sides of a tank seat are brackets providing loops for detachable connection to hooks. An inelastic fabric web, such as of woven nylon, adjustably threads around a buckle bar on one hook, and returns along the inside of the web for firm attachment by hook and mesh fasteners such as "VELCRO". The other end of the web fixedly attaches to a metal loop that cooperates with a high leverage toggle mechanism. The toggle mechanism comprises but two parts, the first being a bar forming a hook detachably coupled to the corresponding back plate bracket, the second being a lever hinged to the bar and providing a recess to receive the loop for over center lock and release of the loop by toggle action.

Abstract: A diving snorkel is provided with a purge valve located in a branch or bypass conduit. The branch conduit connects with the main snorkel conduit at a place remote from the mouthpiece. When the diver resumes a snorkel attitude after the snorkel has been filled with water, the purge valve allows water in the projecting end of the snorkel to drop to the level of the water surface, minimizing the amount of water required to be purged for snorkel breathing. The remote location of the purge valve provides efficient utilization of exhalation effort.