Patent ID: 8881731

Claim:
A respiratory mask system, contacting the face of a user for supplying respiratory gas under positive pressure to the user, comprising: a mask cushion covering a nose, a nose and a mouth or a full face; a first frame connected with the mask cushion enabling to supply respiratory gas under positive pressure from a means for supplying respiratory gas under positive pressure; and a second frame connected with a headgear strap, the mask cushion being disposed on the face side of the first frame and the first frame being disposed on the face side of the second frame, a pair of slide surfaces being correspondingly formed in the side of the first frame facing the second frame and in the side of the second frame facing the first frame, and the first frame being connected slidably with the second frame along the slide surface, and the first frame and the second frame being relatively rotatable in any direction by 360° along the pair of slide surfaces, wherein a holding-down section is provided to prevent detachment of connection between the first frame and the second frame, even if tension is not applied to a headgear strap or pressure of respiratory gas under positive pressure is not applied, the provision of the holding-down section preventing the both first and second frames from detaching, wherein at least one slide surface of the pair of slide surfaces is formed along a portion of a hypothetical sphere, having a center, the slide surface having a spherical surface and a convex shape protruding in the direction opposite to the face side, and the first frame is connected with the second frame in a ball-joint like form through the slide surface, and wherein center of a revolving movement of a user's head from side to side and up and down is positioned on or near the center of the hypothetical sphere.