GB314099A - Improvements in or relating to apparatus for use in the manufacture of artificial filaments, films or the like - Google Patents

Abstract

314,099. British Celanese, Ltd., and Kinsella, E. Dec. 17, 1927. Fluid-actuated valves.-A device for use in the manufacture of artificial silk, films, &c. for delivering a constant flow of liquid under pressure, comprises a. static measuring-device of the orifice, capillary tube, construction or other type, the communication from the source of liquid under pressure to the static measuring-device being through a valve the motor-member of which is exposed on opposite sides to the pressures on the inlet and delivery sides of the static measuring-device, the arrangement being such that a constant difference as between the pressures is maintained. The static measuring-device may also be provided with means such that the desired constancy is preserved notwithstanding variations in the temperature of the liquid. In the form shown in Fig. 1, the static measuring- device consists of an orifice 18 in a plate 17, and the pressure-balance valve comprises a piston valve member 6 mounted on a piston 5, the latter, by means of appropriate passages, being exposed on opposite sides to the pressures on the inlet and delivery sides of the static measuring- device ; the valve 6 controls by one or more ports 12 the supply of liquid under pressure from a groove 13 communicating with the inlet pipe 1, and the construction is such that should an excess pressure develop on either side of the static measuring-device, the supply of liquid is cut off temporarily. In this form the necessary pressure-difference is obtained by means of a spring 16. In other forms the difference of pressure is obtained by employing a heavy piston 5, Fig. 4, the parts being suitably re-arranged; and the piston is replaced by a diaphragm 28, Fig. 3, and the piston valve 6 by a double conical valve 30, Fig. 3. To ensure constant delivery under varying temperatures a conical member 21, Figs. 1 and 2, mounted on a bimetallic strip 22, is fitted within the orifice 18 of the static measuring-device, the parts being arranged so that the conical member 21 enters more deeply into the orifice as the temperature rises. As an alternative, the control-member 21 may be mounted on an expansible capsule 22, Fig. 4, containing a liquid, and, in this case, the member is connected by means of an extension 21A to a diaphragm 26 so that the pressure on the capsule is balanced by the pressure on the diaphragm, actuation of the member 21 by variations in the liquid pressure being thereby avoided.