Patent GB-233384-A (GB)
Title: Improvements in or relating to processes and apparatus for the manufacture of artificial threads or filaments
IPC: D01F2/30
Filed: 1924-01-03
Abstract: 233,384. Soc. pour la Fabrication de la Soie Rhodiaseta, and Grillet, N. Jan. 3, 1924. Apparatus for making filaments.- Uniform conditions are maintained throughout the groups or sub-groups of cells of a dry-spinning plant by providing the cells with a double set of temperature-controlling elements, identical for the groups of the cells and through each of which flows a current of temperature-controlling fluid in series as regards each of the sets but in reversed sequence in opposite directions relatively in the one set to the other set. The temperaturecontrolling elements may be fitted inside the cells, or they may be arranged to heat the supply of gaseous medium passing to the cells. Thus, each cell is provided with two identical heating or cooling elements 8, shaped as shown in Fig. 2 to permit of the passage of the filaments; and these elements of the groups of cells are connected in series so as to form two sets of heating &c. elements; through one set passes, for example, a stream of hot water, the elements of this set gradually falling in temperature; through the other set passes in the opposite direction either a separate stream of hot water, or the same stream as in the first set either with reheating or without heating, the elements of this set showing also a fall of temperature towards the end of the set, but the arrangement is such that as regards the individual cells, the element of highest temperature of the one set is associated with the element of lowest temperature of the other set, and so on. To ensure uniformity of evaporation in addition to uniformity of temperature, the gaseous current passing through each of the cells and which serves to effect the evaporation of and to carry off the solvent is controlled as follows,-there is comhined with the temperature-controlling arrangements above referred to, means for ensuring in a simple manner uniformity of flow of the gaseous medium in the individual cells of a group or sub-group, such means comprising on the one hand the employment of collecting or supply piping 27, 29 of such dimensions that under the conditions of operating the loss of head throughout the system is negligible, and on the other hand the provision in the connections to the individual cells of each group or sub-group, of devices 26, which produce a fixed, predetermined and substantial loss of head and which are interchangeable but not individually adjustable; such devices are conveniently tubes of small diameter and of definite length, or plates of definite thickness and pierced with holes of definite diameter. The rate of flow through the cells of a group is adjusted by reguiating the head producing the flow in the collecting or supply piping. The flow of gaseous medium through the cells may be produced by aspiration or by positively forcing the medium through the cells; the gaseous medium leaving the aspirator may be reused, for example, after the recovery of the vapours carried away by it. The collecting piping through which the gaseous medium carrying the vapours of the solvents is led away from the cells may be provided with devices for preventing the propagation of an explosion such as gauze partitions, paper discs that are easily ruptured to provide relief openings, or with elbow connections that cause a sudden change of direction in the gases. Specification 218,913 is referred to.