GB124827A - A Combined Pressure and Static Head for Air Speed Indicators. - Google Patents

Abstract

124,827. Aeronautical Instrument Co., and Brewer, G. April 28, 1916. Pitot-tube apparatus.-A swivelling pressure-head for air-speed indicators of streamline form, constructed to convey both wind and static pressures to a differential pressure gauge on which the speed is indicated, is mounted upon a pivot carried by a tubular member and is provided with means for keeping the head of the device to the wind. The tubular member bearing the pivot is in communication with the wind-pressure chamber and is carried by a tubular mast, which may enclose a second tube communicating the static pressure of the secondary atmosphere, or may itself constitute the communicating means, the combined pressures being conveyed thereby to an indicating-device, such as that described in Specification 13796/13. A tube 4, Fig. 1, mounted in the nose of the device communicates with a casing constituted by a tube 5, an upper cap 6, and a lower cap 12, through which passes a tube 9, carried by the perforated upper end of which is a pivot 8, a bearing 7 therefor being carried by the cap 6. The casing 5 is rendered air-tight by a felt or like washer 11 secured so as to be capable of longitudinal movement between the cap 12 and a screwed end 13. Surrounding the lower end of the tube 9 and carried by the tubular mast is a second tube 10 closed at its upper end and perforated at 15 to communicate with tlie interier of the casing, which itself is connected with the exterior air by holes 16. Balance weights 18, provided with cavities 19 to receive shot, are mounted in the head. The tail 20 is made to diverge towards the rear as shown in Fig. 2, the preferred angle being 10 degrees.