Nasal respiratory mask system and connection/disconnection means used therein

A connection/disconnection means comprising a fastener and a fastener catch;

• the fastener comprises a pair of clamping portions, and
• an approximately V-shaped tip portion that is formed protruding on front ends of the pair of clamping portions and engages with the fastener catch by being received therein;
• and
• the fastener catch comprises an axisymmetric guide whose axis is an insertion direction of the fastener, the shape of the guide is an indentation having a spindle shape or a cone shape, and the fastener has an approximately V-shaped protruding portion adapted to the indentation
• wherein, at an open end of the guide, the indentation has a smooth circular inner wall along an entire periphery thereof and extending a predetermined axial length of the indentation such that the headgear fastener can be inserted into the fastener catch in any rotational direction,
• wherein the fastener is rotatable about the axis of the insertion direction even when engaged at an engagement site with the fastener catch and
• wherein the fastener is rotatable by at least 30 degrees with respect to the fastener catch at the engagement site with the fastener catch.

A nasal respiratory mask system comprising:

• a nasal mask configured to be attachable to a face of a user and serves as means for supplying positive-pressure breathing gas to a nose of the user;
• a frame to keep the nasal mask at a predetermined position;
• and
• a headgear configured to be mountable on a head of the user in order for the nasal mask to be attachable to the face of the user, wherein
• the headgear comprises a headgear strap configured to adjust the length of the headgear, the headgear strap comprises a headgear fastener that serves as means for connection/disconnection with the frame, the frame comprises a fastener catch that engages with the headgear fastener, the fastener catch comprises an axisymmetric guide whose axis is an insertion direction of the headgear fastener, the shape of the guide is an indentation having a spindle shape or a cone shape, and the headgear fastener has an approximately V-shaped protruding portion adapted to the indentation,
• wherein the headgear fastener includes a lock hook piece, a clamping portion and a strap hook integrally connected together with a notch incorporated with one of the lock hook piece, the clamping portion and the strap hook or disposed between connected ones of the lock hook piece, the clamping portion and the strap hook and
• wherein, at an open end of the guide, the indentation has a smooth circular inner wall along an entire periphery thereof and extending a predetermined axial length of the indentation such that the headgear fastener can be inserted into the fastener catch in any rotational direction.

A nasal respiratory mask system comprising:

• a nasal mask configured to be attachable to a face of a user and serves as means for supplying positive-pressure breathing gas to a nose of the user;
• a frame to keep the nasal mask at a predetermined position;
• and
• a headgear configured to be mountable on a head of the user in order for the nasal mask to be attachable to the face of the user, wherein
• the headgear includes a headgear strap configured to adjust the length of the headgear, the headgear strap includes a headgear fastener for connection/disconnection with the frame, the frame includes a fastener catch that engages with the headgear fastener, the fastener catch includes a guide body disposed about and extending along an axisymmetric axis defining an insertion/retraction direction of the headgear fastener, the guide body having an inner guide body surface forming a generally conically-shaped reception hole extending along and about the axisymmetric axis and having a pair of lock holes extending through the guide body transversely to the axisymmetric axis and into the conically-shaped reception hole, the headgear fastener including a pair of clamp arms connected together at respective proximal clamp arm ends to form a generally V-shaped configuration and extending therefrom to terminate in respective distal clamp arm ends, each one of the pair of clamp arms having an inner clamp arm surface with respective ones of the inner clamp arm surfaces facing each other and an outer clamp arm surface facing away from the respective inner clamp arm surfaces, a pair of release levers with a respective one of the release levers integrally connected to respective ones of the distal clamp arm ends, a strap hook extending between and integrally connected to at least one of the pair of release levers for retaining the headgear strap to the headgear fastener and a pair of lock hook projections with a respective one of the pair of lock hook projections integrally connected to and projecting outwardly from respective ones of the outer clamp arm surfaces,
• wherein respective ones of the outer clamp arm surfaces are arcuate in shape as viewed cross-sectionally in a plane extending transversely to the axisymmetric axis such that, when the pair of clamp arms are inserted into the conically-shaped reception hole of the guide body, the outer clamp arm surfaces of the respective ones of the pair of clamp arm members arcuately comport with and facially oppose the inner guide body surface while the pair of lock hook projections are received in respective ones of the pair of lock holes.