Abstract: Self-contained breathing apparatus comprising a portable tank containing a supply of breathing air under high pressure, a main pressure regulator for reducing the pressure of air from the tank to a moderate level, a face mask having a demand valve mounted thereon which receives air from the main pressure regulator through a main supply hose and which controls the pressure and flow thereof to meet the users requirements, a bypass pressure regulator and flow control means which receives air from the tank and which controls the pressure and flow of air to the mask, through a separate bypass hose, to provide breathing air to the mask in the event of a fault in the main breathing circuit. The bypass hose is attached to the bypass pressure regulator and flow control by means of manually operable quick disconnect fitting, enabling emergency sharing of the air supply by a second, similarly equipped user.

Abstract: A unitary device for splitting into substanitally equal halves a previously uncut muffin, or the like. The device is constructed in two hingedly-connected parts each having a plurality of tines extending fixedly therefrom in parallel relation. The parts are moved to a first position, wherein all the tines are arranged in a single, parallel row, and a muffin is inserted sideways so that it is pierced by the tines. Upon movement about the hinged connection away from this position the tines of the two parts are separated, breaking the muffin transversely into two parts.

Abstract: A chamber in a valve case has an inlet port of exhaled air in one of its end walls. Spaced inwardly from the side wall of the chamber is a valve seat surrounding the inlet port and engaged by one side of a sealing member, the opposite side of which is engaged by a rigid disc secured to a valve stem that extends through the port and into guiding means for the stem. The diameter of the disc is nearly as great as the diameter of the chamber. A spring in the case is compressed between the disc and the other end wall of the valve chamber for pressing the sealing member against the seat. The disc is spaced from the ported wall of the chamber far enough for the marginal portion of the disc that extends laterally out beyond the sealing member to be inclined toward the ported wall but spaced from it.