Dual mode breathing apparatus

A facemask configured for use with a breathing apparatus, the facemask comprising:

• a regulator comprising an inlet configured for connection to a tank containing a pressurized breathing gas, an outlet for providing the pressurized breathing gas to a user, and a valve configured for controlling a flow of the pressurized breathing gas between the inlet and the outlet based at least in part on the respiration of the user;
• a facepiece comprising a first port configured to be placed in fluid connection with the outlet of the regulator to introduce the pressurized breathing gas into the facepiece, a second port adapted to be connected to an air purifying system, and an exhalation valve for exhausting exhaled breath from the facepiece;
• a pneumatic pressure adjustment assembly in operative connection with the exhalation valve and operable to adjust the internal facepiece pressure required to open the exhalation valve based on whether the pressurized breathing gas is delivered to the pneumatic pressure adjustment assembly;
• and
• an alignment mechanism for aligning the regulator with the facepiece such that the pin is configured to be received within the recess when a first pneumatic connection of the pressure adjustment assembly in the facepiece is aligned with a corresponding second pneumatic connection of the pressure adjustment assembly in the regulator, wherein the alignment mechanism comprises a pin on one of the regulator and the facepiece and a corresponding recess on the other of the regulator and the facepiece,
• wherein the regulator is rotatable relative to the facepiece until the pin is received through an open end of the recess and engages a closed end of the recess,
• wherein the regulator comprises a connection element configured for mechanical connection of the regulator to the facepiece,
• wherein the mechanical connection is a bayonet connection, a spring-loaded detent connection, or a press-in connection, and
• wherein the connection element and the alignment mechanism are separate components of the breathing apparatus.

A breathing apparatus comprising:

• a tank configured for containing pressurized breathing gas;
• a regulator comprising an inlet for connection to the tank via a first airline, an outlet for providing the pressurized breathing gas to a user, and a valve configured for controlling a flow of the pressurized breathing gas between the inlet and the outlet based at least in part on a respiration demand of the user;
• a facepiece comprising a first port configured to be placed in fluid connection with the outlet of the regulator to introduce the pressurized breathing gas into the facepiece, a second port adapted to be connected to an air purifying system, and an exhalation valve for exhausting exhaled breath from the facepiece;
• a pneumatic pressure adjustment assembly in operative connection with the exhalation valve, the pneumatic pressure adjustment assembly having a first pneumatic connection in operative connection with a second pneumatic connection in the regulator, the pneumatic pressure adjustment assembly operable to adjust an internal facepiece pressure required to open the exhalation valve based on whether the pressurized breathing gas is delivered to the pneumatic pressure adjustment assembly via the second pneumatic connection in the regulator;
• a mechanical connection that mechanically connects the regulator and the facepiece;
• and
• an alignment mechanism for aligning the regulator with the facepiece such that the first pneumatic connection of the pressure adjustment assembly in the facepiece is aligned with the second pneumatic connection in the regulator, wherein the alignment mechanism comprises a pin on one of the regulator and the facepiece and a corresponding recess on the other of the regulator and the facepiece,
• wherein the regulator is rotatable relative to the facepiece until the pin is received through an open end of the recess and engages a closed end of the recess, and
• wherein after the pin is received within the recess, the pin remains axially movable within the recess until the regulator and the facepiece are fully connected.