A pulse modulated oxygen dispensing and pressurization system provides a variable range of controlled oxygen bolus to an enclosed breathing environment supporting and maintaining required pressure conditions in accordance with desired flow demand. As oxygen is consumed by the user from within the enclosed breathing environment, the exhaled gases and moisture are conditioned or vented to acceptable levels by additional systems associated with the environment. These additional systems cause an ongoing need to replenish the oxygen within the environment and maintain the required partial pressure of oxygen. Specific to one of a plurality of modes of operation, the system responds to changes in regulated output pressure by delivering a precisely metered periodic bolus volume of oxygen to support a requirement of the environment volume. The bolus is variable based on a plurality of factors to increase and decrease changes in rates of flow required to maintain regulated pressure.

A pulse modulated oxygen dispensing and pressurization system provides a variable range of controlled oxygen bolus to an enclosed breathing environment supporting and maintaining required pressure conditions in accordance with desired flow demand. As oxygen is consumed by the user from within the enclosed breathing environment, the exhaled gases and moisture are conditioned or vented to acceptable levels by additional systems associated with the environment. These additional systems cause an ongoing need to replenish the oxygen within the environment and maintain the required partial pressure of oxygen. Specific to one of a plurality of modes of operation, the system responds to changes in regulated output pressure by delivering a precisely metered periodic bolus volume of oxygen to support a requirement of the environment volume. The bolus is variable based on a plurality of factors to increase and decrease changes in rates of flow required to maintain regulated pressure.

A rebreather apparatus includes at least one pressurized container of oxygen, at least one pressurized container of a diluting gas, and at least one valve to supply the oxygen and diluting gas to a rebreathing loop. The valve is controlled by a signal from at least one oxygen sensor, wherein the oxygen and diluting gas combine to form a breathing gas that is circulated by the rebreathing loop. At least one container of calibrating gas stores the calibrating gas at ambient pressure and temperature. At least one valve is connected to the at least one oxygen sensor presenting the calibrating gas to the oxygen sensor during calibration of the oxygen sensor and presenting the breathing gas to the oxygen sensor at all other times.

A rebreather apparatus includes at least one pressurized container of oxygen, at least one pressurized container of a diluting gas, and at least one valve to supply the oxygen and diluting gas to a rebreathing loop. The valve is controlled by a signal from at least one oxygen sensor, wherein the oxygen and diluting gas combine to form a breathing gas that is circulated by the rebreathing loop. At least one container of calibrating gas stores the calibrating gas at ambient pressure and temperature. At least one valve is connected to the at least one oxygen sensor presenting the calibrating gas to the oxygen sensor during calibration of the oxygen sensor and presenting the breathing gas to the oxygen sensor at all other times.

A scrubber-heating apparatus for a diving rebreather includes an oxygen supplying element. The oxygen supplying element has a gas mixing portion connected thereto. The gas mixing portion has a breath connecting element connected thereto. The breath connecting element has a scrubber connected thereto. The scrubber is provided with an absorbent heating element and a temperature detecting component. The temperature detecting component has a state display connected thereto. The absorbent heating element and the state display are electrically connected to a power supplying portion. Thereby, the scrubber can recycle gas exhaled by a user to prolong the duration of use of the rebreather. Additionally, the absorbent heating element increases the temperature in the scrubber, thereby enhancing the adsorption efficiency and prolonging the overall duration of use.

An apparatus for adjusting the partial pressure of gaseous mixtures comprises a housing and piston. The housing defines a chamber coupled to an oxygen metering orifice, diluent metering orifice, vent port and gas outlet. The oxygen metering orifice provides oxygen to the chamber and the diluent metering orifice provides diluent gas to the chamber. The piston is movably positioned in the chamber and includes first and second sealing devices. The chamber is sectioned into a mixing chamber, a diluent chamber and a reference chamber located between the mixing chamber and diluent chamber. The diluent chamber receives a diluent gas referenced at ambient pressure and the reference chamber is charged with a gas having a reference pressure. The piston changes positions within the chamber depending on a force balance created by a pressure differential between the reference pressure and ambient pressure.

A method and apparatus for automatically controlling partial pressure of oxygen in the breathing loop of a rebreather diving system. A diver may adjustably select a control parameter to maintain partial pressure of oxygen at a setpoint that varies with ambient pressure and is within a range between a maximum safe partial pressure of oxygen at depth and a minimum safe partial pressure of oxygen for the purpose of biasing the performance of the rebreather either towards minimizing gas venting from the rebreather breathing loop or minimizing decompression time. A method and apparatus for managing and monitoring the use of dive resources in comparison with a target dive time specified by the diver, calculating and indicating remaining dive time based on dive resource values and calculating and indicating dive resource values required to meet preselected dive resource end values and dive requirements.

A method and apparatus for automatically controlling partial pressure of oxygen in the breathing loop of a rebreather diving system. A diver may adjustably select a control parameter to maintain partial pressure of oxygen at a setpoint that varies with ambient pressure and is within a range between a maximum safe partial pressure of oxygen at depth and a minimum safe partial pressure of oxygen for the purpose of biasing the performance of the rebreather either towards minimizing gas venting from the rebreather breathing loop or minimizing decompression time. A method and apparatus for managing and monitoring the use of dive resources in comparison with a target dive time specified by the diver, calculating and indicating remaining dive time based on dive resource values and calculating and indicating dive resource values required to meet preselected dive resource end values and dive requirements.

A system and method for determining a remaining processing capacity of a scrubber having a flow path and a processing material disposed along the flow path. A device may comprise a plurality of optical sensors disposed within the processing material and arranged along the flow path, a light source, and a processor for determining the capacity according to signals received from the optical sensor. The device may be used to illuminate processing material adjacent to each optical sensor using the light source, measure a light value reflected by the processing material at each optical sensor, and determine the remaining processing capacity of the scrubber, using the processor, based on the measured light value. Devices may comprise a memory, such as a non-volatile memory to allow multiple uses of a scrubber without reloading with fresh processing material.

Diving equipment includes a compressed air bottle connected to a breathing apparatus and an inflatable jacket via which buoyancy is balanced by the jacket being connected to the compressed air bottle to be inflated or to an outlet to be deflated. A monitoring device is activated via a control valve as a function of surrounding water pressure and has a time monitoring unit which, after the expiry of a defined time and in the absence of breathing activity in the breathing apparatus, changes to emergency operation and activates an emergency valve via a control line connecting the jacket to the compressed air bottle to force inflation of the jacket. Actuation of at least one regulating valve is influenced during a dive by the monitoring device and/or the control valve. In manual activation, the jacket is inflated via the inflation valve, and the compressed air is bled via the outlet valve.