Abstract: A protective respiratory device (1) in the form of a half-mask (2) is designed to cover the nose and the mouth of the wearer and is combined with a bag-shaped hood (3) designed to enclose the head of the wearer and provided with a visor (12) in front. Round the bag opening, the hood (3) is provided with an elastic sleeve designed to surround the neck of the wearer in a tight-fitting fashion. A first elastic band (9) arranged in the hood extends between the two sides of the half-mask and is intended to be applied round the back of the head or the nape of the neck of the wearer. A second elastic band (13) arranged in the hood and extending rearwards from a hood portion corresponding to the forehead of the wearer is connected to the first band (9) at the back. The second band (13) is adapted to be placed over the crown of the head of the wearer and has such a width that it will then largely surround the head of the wearer also laterally.

Abstract: A filter container for direct or indirect connection to a protective mask comprises a cup-shaped casing having a bottom wall with an inhalation air intake formed therein, a cover closing the casing and having a top wall with an inhalation air outtake formed therein, a particle filter disposed within a bottom portion of the casing and secured around its circumference to an inner sidewall of the casing, and an absorption filter mounted between the particle filter and the cover within an upper portion of the casing. The bottom wall of the casing has a plurality of inwardly projecting, circumferentially spaced, radially directed stiffening ribs formed thereon, and the stiffening ribs have inwardly facing longitudinal edges lying substantially in a single plane. The particle filter has upper and lower folds, and engages at lower folds thereof the inwardly facing longitudinal edges of the stiffening ribs and engages at upper folds thereof a member supporting a bottom of the absorption filter.

Abstract: The invention concerns a filter container for an absorption filter (8) and a particle filter (7), the container being adapted to be connected to a protective mask.

Abstract: An apparatus for folding a sheet along concentric circular arcs comprises two series of chain driven comb-shaped folding elements. The folding elements of each series are spaced apart by a distance which is approximately twice the distance between the intended fold locations on the sheet, with the elements of one series being arranged to act against one side of the sheet and the elements of the other series being arranged to act against the other side of the sheet. The folding elements of one series are offset relative to those of the other series a distance equalling the distance between adjacent fold locations on the sheet. The elements of one series increasingly overlap the elements of the other series along the length of the sheet, whereby a plurality of folds are simultaneously being formed progressively as the sheet is fed between the two series of folding elements.