US 908108 A
Description (OCR text may contain errors)
' H. KNUDSEN. FIREMANS MASIK. APPLICATION FILED AUG. 7, 1306- Patented Dec, 29, 19%.
mmwzoa- ITESI S'ES.
Learns HANS KNUD EN, 0F MINNEAPOLIS, MINNESOTA.
' FIREMANS mask.
Specification of Letters Patent;
PatentedDec. 29, 1908.
Application filed August 7, 1906. Serial No. 329,595.
To all whom it may concern:
Be it known that I, Hans Kuunsnu, a subject of the King of Denmark, residing at Minneapolis, in the county of Hennepin and State of Minnesota, have invented certain new and useful Improvements in Firemens Masks and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the figures of reference marked thereon, which form a part of this specification.
My invention relates to improvements in firemens masks, or means for separating the smoke in a burning building from the air a person must inhale who is in the building or must enter it while there is smoke in the rooms.
The invention consists of the means hereinafter described and fully pointed out in the In the accompanying drawing Figure 1 is a front View of a persons head wearing my mask, the exhaust tube for the air having its front end removed to give a full view of a rotarry fan within the mask. Fig. 2 is a side view of Fig. 1 with the mask shown as made of'canvas with a portion broken away to expose the face and the fan and fan-driving mechanism in front of the nose and mouth. Fig. 3 is the front end of the exhaust tube removed from infront of the fan in Fig. 1.
Referring to the drawing by reference numerals, 1 designates. the neck, 2 the head and 8 the hat of a fireman or other person upon whom the mask is illustrated.
' Fastened to the hat or free from it, as
may be desired, is a hat-shaped su portingframe 4:, which rests on the head an may be used with or without the hat 3 over it. By the brim of the light wire hat 4 is supported a suitable wire frame 5 which comes down as shown at the back, sides and front of the head. .In the front part of the frame 5 is fixed a box-shaped frame 6 having in its upper part a protruding tube 7, with a hinged 11d 8, normally kept closed by a very light spring 9.
In the frame 6 is mounted a train of speedincreasing gear wheels 10, (best shown in Fig. 2) of which the slowest shaft 11 isdriven by a clockspring 12, which may at any time be wound up by the key 13, ratchet-Wheel 14 and ratchetdog 15; allarranged on. well known clock-spring and gear principle; and the fastest-running shaft '16 carries the fan 17, by which, when the gears are running, the smoke is prevented from entering the tube 7, as a constant current of air from the fan kee s itout.
e frame work 4-5 is covered by a hood 18 uniting closely with the mechanism framefi, and having in its lower part an opening through which the head is inserted, and then the opening is drawn sufficiently tight about the neck by an elastic string or band 19 inclosed in the lower edge of the hood, said lower edge or also be made altogether of thin flexible rubber, so that the string may be dispensed with. The rest of the canvas or cloth in the hood may be of silk, cotton, wool, or other fabric or material that prove to be the best for filtering the smoke-substances out of the air as the air is drawn through the canvas by the partial vacuum created within the hood by the action of the fan.
The functions of the lid 8 is to close the tube 7 against the smoke whenever the fan runs too slow to keep the. smoke out, because the spring needs winding.
'From this it will be understood that if reliable and ion -lasting driving means, like a good electric attery, is employed to drive the fan, or if the winding of the spring 12 is properly attended to the lid 8 may be disensed with. And, again, the lid may to air-advantage be used without the fan and its driving mechanism, as the, lungs of the wearer of the mask draws the air in through the mask, ejects it through the tube 7, which may be'closer to his mouth than shown, the lid 8 opening for each exhalation or puff of air from the lungs and closing during the inl 1alation.-
20 are comparatively large pieces of lass,
or preferably mica, inserted in the mas for lid. ever the opening of the tube, a rotating l ture, in presence of two witnesses.
fzip expelling air through the tube, and suitable means for driving the fan, said driving ins consisting of a train of speed-increasing gear wheels, a spring running the train of Wheels and a key for winding the spring.
JOHN ROSVOLD, ARTHUR Rosvow.
In testimony whereof I am); my signs"