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United States Patent (10) Patent N0.: US 6,666,623 B1 Greene (45) Date of Patent: Dec

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United States Patent (10) Patent N0.: US 6,666,623 B1 Greene (45) Date of Patent: Dec US006666623B1 (12) United States Patent (10) Patent N0.: US 6,666,623 B1 Greene (45) Date of Patent: Dec. 23, 2003 (54) BUOYANCY CONTROL DEVICE AND 5,560,738 A * 10/1996 Noel ........................ .. 405/186 METHOD FOR CONTROLLING DIVERS 6,287,053 B1 * 9/2001 Garofalo et al. .......... .. 405/186 ASCENT 6,435,032 B1 * 8/2002 Holloway et al. .......... .. 73/713 2002/0127062 A1 * 9/2002 Biran et al. ............... .. 405/186 (75) Inventor: gsuegiard M. Greene, White Plains, NY FOREIGN PATENT DOCUMENTS GB 2246745 * 2/1992 ................ .. 441/88 (73) Assignee: Safe Flight Instrument Corporation, * . White Plains, NY (US) ‘med by exammer Primary Examiner—Jong-Suk (James) Lee ( * ) Notice: Subject to any disclaimer, the term of this (74) Attorney, A gem, 0r Firm—Dennison, Schultz & patent is extended or adjusted under 35 Dougherty U.S.C. 154(b) by 0 days. (57) ABSTRACT (21) APPL NOJ 10/167,585 Abuoyancy control device includes a buoyancy compensa (22) Filed Jun 13 2002 tor to be Worn by a scuba diver, a compressed air tank, a ' ' ’ depth or pressure gauge and a valve connecting the buoy ( 51 ) Int. Cl.7 .............................................. .. B63C 11/02 anc y com P ensator and com p ressed air tank for releasin g air (52) US. Cl. ....................... .. 405/186; 405/185; 441/88; mm and out of the buoyancy compensator- Amicroprocessor 441/96 is connected to the depth gauge and the valve for controlling (58) Field Of Search ............................... .. 405/185, 186; the amount of air in the buoyancy compensator in response 114/315, 331; 441/80, 88, 92, 96, 106, to the depth of the diver. In addition, the microprocessor is 108 programed for automatically controlling the rate of ascent of a diver under normal conditions and for a faster rate of (56) References Cited ascent under emergency conditions. The device also includes an override function Which alloWs a second diver to US- PATENT DOCUMENTS override the normal rate of ascent and to initiate the faster 4,051,846 A * 10/1977 McClure, III ............. .. 405/186 rate of ascent 1“ an emergency 4,324,507 A * 4/1982 Harrah . .. 441/92 5,542,446 A * 8/1996 Rose ....................... .. 137/812 8 Claims, 3 Drawing Sheets Buoyancy 80 Control Device Input 1st 81 Rate of 5 Ascent Input 2nd Rate of 5 82 Ascent Dive to Selected 5 85 Depth 5 84 | t t 2 d Initiate 1st n ic e n 86 Rate of no Rate of S Ascent Ascent yes yes Proceed to 85 Proceed to 87 Surface 5 Surfuce S U.S. Patent Dec. 23, 2003 Sheet 1 of3 US 6,666,623 B1 FIG. 1 (PRIOR ART) U.S. Patent Dec. 23, 2003 Sheet 2 0f 3 US 6,666,623 B1 10 Flexible Air Bladder N 44 49 Flow Flow 53 Meier Meier 78 55 51 A’ 50 46 Z ‘ 57 5 48 Fill Valve Release Valve DriverWi’rh Elec’rronicCircuilry DriverWilh EleclronicCircui’rry 47 54 /l3 74 Pressure 70 Sensor \< f\/ 72 Analog __ fJ Mul’riplexer TemperalureSensor /< 76 ~71 755 Ana|og—To—Digi’ral Converler “67 68% ~69 Embedded 61; j Compuler f/ 60 @V66 62 65 FIG.2 Ii Driver Conlrol Panel :IlN (PRIOR ART) U.S. Patent Dec. 23, 2003 Sheet 3 0f 3 US 6,666,623 B1 Buoyancy 8O Con’rrol j Device \npu’r 151 81 Ram of 5 Ascen’r Inpu’r 2nd Ro’re of 582 FIG.3 Asceni Dive To Selec’red 583 Depth 584 Ini?die 1s’r ln’rio’re 2nd 86 Rd’re of no * Ro’re of 5 Ascem‘ Ascen’r yes yes Proceed to 85 Proceed +0 87 Surface 5 Surface 5 9O 89 US 6,666,623 B1 1 2 BUOYANCY CONTROL DEVICE AND pensator. The Leonard device is used in conjunction With METHOD FOR CONTROLLING DIVERS underWater equipment Which is provided With an adjustable ASCENT buoyancy chamber. The Leonard patent is also incorporated herein in its entirety by reference. NotWithstanding the advances disclosed in the aforemen FIELD OF THE INVENTION tioned patents, it is presently believed that there is a need and This invention relates to a buoyancy control device for a commercial demand for an improved buoyancy control scuba divers and more particularly to a buoyancy control device. It is believed that there is a need for a device in device for controlling the vertical motion of a scuba diver accordance With the present invention that provides buoy 10 under normal and emergency conditions. ancy control Without excessive diver attention through all phases of the dive. In addition, the buoyancy control device BACKGROUND FOR THE INVENTION in accordance With the present invention provides for auto mated compensation for changes in buoyancy of a scuba Buoyancy compensators for scuba divers are Well knoWn tank as the air is consumed by a diver. for use in controlling buoyancy While diving. Such com 15 A further advantage of the buoyancy control devices in pensators typically consists of a ?exible air bladder and accordance With the present invention is that they provide hand-activated pneumatic ?ll and release valves. In this automatic vertical propulsion and vertical velocity control of manner, the buoyancy force acting on the diver is changed a diver during the descent portion of the dive and also during by adjusting the volume of air in the ?exible bladder. the ascent portion of the dive. A still further advantage of the Such compensators generally require careful attention present device is the inclusion of a safety feature that alloWs from a diver to attain and maintain neutral buoyancy, to a diver or a second diver to provide for a relatively fast safely descend, to safely ascend and to establish adequate ascent under an emergency With a limited risk of a lung positive buoyancy at the surface. The diver controls buoy expansion injury or decompression sickness. ancy by using the hand-activated air valves to add and 25 Further, the improved device in accordance With the release air to and from the buoyancy compensator. Such present invention alloW a second diver to send an injured or control is based on vertical motion changes, references to unconscious diver to the surface unaccompanied by the stationary objects or the use of a depth gauge. second diver at a controlled rate. In addition, it is believed Neutral buoyancy is achieved at a selected depth and must that the devices in accordance With the present invention can be adjusted as the depth of the dive changes. A deviation be manufactured at a competitive price, and are reliable and from neutral buoyancy also occurs due to changes in the durable. hydrostatic pressure of the Water Which changes in depth as Well as changes in the loss of Weight as air from the BRIEF SUMMARY OF THE INVENTION compressed air tank is used. In essence, the present invention contemplates an An improved buoyancy compensator that reduces the 35 improved buoyancy control device for scuba divers. The scuba divers attention and exertion required for buoyancy device includes a buoyancy compensator or vest to be Worn control is disclosed in the US. Pat. No. 5,496,136 of Egan. by or attached to a diver. The device also includes one or As disclosed therein, a buoyancy compensator includes an more compressed air tanks adapted to be carried by a diver electronic sensor/valve assembly and a ?exible air bladder in a conventional manner and means such as a depth or Which automates and controls the vertical motion of a diver. pressure gauge for measuring the depth of a diver. A valve A computer acquires pressure, temperature and air ?oW data or other means is connected to the buoyancy compensator to determine the diver’s vertical motion and the amount of and the compressed air tank for releasing air from the air in the bladder. The computer controls electronic ?ll and compressed air tank into the buoyancy compensator and for release valves to change the volume of air in the bladder. releasing air out of the buoyancy compensator. The device Algorithms are implemented by the computer to automate 45 also includes a microprocessor operatively connected to the controlled vertical propulsion for ascending, descending, means for measuring the depth of the diver and to the valve neutral buoyancy, maintenance and surface operation. Auto for controlling the amount of air in the buoyancy compen mated transitions are provided betWeen modes of operation sator in response to the depth of a diver. In addition, the and for a timed safety stop during the ascent from the dive. device includes means for inputting a ?rst selected rate of Another approach for an improved buoyancy compensa ascent for controlling the vertical movement of a diver under tor device is disclosed in the US. Pat. No. 5,560,738 of normal conditions and a second selected rate of ascent for Noel. As disclosed therein, a depth sensitive diver safety controlling the vertical movement of a diver under emer system is utiliZed With an underWater breathing apparatus. gency conditions. An additional element in the device is The system includes a ?rst automatic ascent control stage means accessible by a second diver for overriding the ?rst Which initiates gradual regulated in?ation of a personal 55 rate of ascent and activating the second rate of ascent. In this ?otation device from a pressuriZed air source When a user Way, a disabled or unconscious diver can be safely sent to the drops beloW a danger/loW air level corresponding to a surface Without escort by a rescuing diver at a rate Which is diver’s depth. The system also includes a second automatic greater than normal but acceptable under emergency condi ascent control stage Which is structured to initiate gradual, tions.
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