GB491609A - Improvements in respiratory masks combined with a helmet - Google Patents

Abstract

491,609. Respiratory masks. CHARBONNEL, P. April 3, 1937, Nos. 9497 and 9498. Convention dates, April 3, 1936 and March 27, 1937. [Class 81 (ii)] A respiratory mask, for military or civil purposes, is normally disposed in the space 3 between the walls 1 and 2 of a double-walled helmet, but is adapted to be pulled out, through a crescent-shaped opening left between the edges of the walls at the front of the helmet, when required for use. Said opening may be closed by a cover provided with a lightning fastener 32, when the helmet is not in use. The facepiece 10 of the mask and the helmet may be made of moulded material mainly composed of synthetic resin. The face-piece 10 is connected by a pair of links 7 to a carriage 5 slidable on curved guides 4 arranged within the space 3, the carriage being normally retracted by rubber cords 6. In the form shown in Figs. 1 and 2, the links 7 also carry a curved member 8 having a rubber pad 8b adapted to fit on the forehead, while rubber side pieces 11, secured to the face-piece 10, are hinged about a pin 8a and are adapted to fit under the chin and on the cheeks. The part 10 is fitted with eyepieces 12 of unbreakable glass and with an exhaust valve 13. On pulling out the mask, downturned flanges on the parts 11 engage in upwardly-opening grooves 20 formed in the helmet wall 1, and the mask is tilted so that a rubber border 15 at the upper part of the part 10 engages in a downwardlyopening groove 16 on the wall 1. The space 3, which is thus in communication with the space between the mask and the face, communicates through an inlet valve 25 with a chamber 26 closed by a hinged cover 27 and containing a filter pad 30. Air is drawn in through an orifice 31 passes through the pad 30 and through the valve 25 into the space 3 whence it passes to the nose past the eye-pieces 12, thus tending to prevent the formation of mist on the latter. The cover 27 is held closed by a hook 28 fastened by a movable ornamental grenade 29. A ventilating opening 21 in the inner wall 2 is closed by a spring-urged valve 22 when the mask is in use, but, when the mask is retracted into the space 3, the valve 22 is opened by a nosepiece 24 carried by the member 8. In the form shown in Fig. 6, air is led through the valve 25 from the filter chamber 26 to the space between the mask and the face by an extensible corrugated tube 35, said space being no longer in communication with the space 3, but being sealed therefrom bv an elastic forehead band 40 secured to the face-piece 10 and side pieces 11. Tension cords 41 apply the band 40 on the forehead, and the mask is held in its operative position by the border 15 engaging the groove 16. According to the Specification as open to inspection under Sect. 91, the ends of the pad 8b are connected to the parts 11. This subject-matter does not appear in the Specification as accepted.