Subnasal sealing cushion and patient interface device employing same

A subnasal sealing cushion for a patient interface device structured to deliver a flow of breathing gas to an airway of a user, comprising:

• a cushion member having a front side and a rear side opposite the front side, the rear side being structured to face a face of the user responsive to the patient interface device being donned by the user, the cushion member including:
• a support portion having a lower oral support portion, an upper nasal support portion, a support structure coupled to an outer wall of the support portion and extending longitudinally along a first direction, the first direction extending from the front side to the rear side, and
• a sealing flap portion coupled to the support portion, the sealing flap portion including an oral sealing portion that transitions into a nasal shelf portion, the nasal shelf portion defining a nasal orifice and being structured to contact a bottom of a nose of the user to create a seal therewith responsive to the patient interface device being donned by the user, the oral sealing portion having an oral orifice that is structured to receive a mouth of the user responsive to the patient interface device being donned by the user,
• wherein the support structure is positioned under and spaced a predetermined distance from a bottom surface of the nasal shelf portion,
• wherein the nasal shelf portion includes opposite side regions which together define the nasal orifice and which are structured to contact the bottom of the user's nose,
• wherein the support structure is positioned proximate the side regions in order to provide support to the nasal shelf portion and prevent collapse thereof,
• wherein the support structure includes a first support wall extending from the lower oral support portion and being made of a first material having a first durometer, and a second support wall extending from the upper nasal support portion and being made of a second material having a second durometer that is higher than the first durometer, and
• wherein the support structure comprises a first plurality of ribs and a second plurality of ribs, each of the first and second pluralities of ribs being coupled to and extending from the outer wall, each of the first plurality of ribs being spaced from one another and positioned one on top of the other, and each of the second plurality of ribs being spaced from one another and positioned one on top of the other.