GB493004A - Improvements in the manufacture of glass sheets, and particularly in their continuous manufacture by means of rotating devices or rollers exposed to heat - Google Patents

Abstract

493,004. Glass manufacture ; hollow rollers; cooling moulds. SOC. ANON. DES MANUFACTURES DES GLACES ET PRODUITS CHIMIQUES DE ST.-GOBAIN, CHAUNY, ET CIREY. July 14, 1937, No. 19527. Convention date, July 16, 1936. [Class 56] [Also in Groups XIII and XXII] Relates to the method of regulating the temperature of rotating devices exposed to heat, particularly the rollers used in the continuous manufacture of glass sheets, by passing cooling- or heating-fluid through the interior of the rollers. According to the invention, the cooling or heating effect is varied in zones extending longitudinally of a roller in order to prevent distortion due to uneven expansion. A roller 1, Fig. 2, may be provided with an axial chamber P which is divided by longitudinal partitions 2-5 into four channels through which water may be circulated. Each channel is supplied with water by a separate pipe provided with a valve to enable the speed of circulation of the water to be regulated independently for each channel, thus varying the cooling-action for four zones 6-9 extending longitudinally of the roller. Control may be exercised, also, by varying the temperature and nature of the fluid circulated through the channels. Instead of using the partitions, the speed of flow of the cooling-fluid may be varied along different parts of the chamber P. This may be done by means of a core 17, Fig. 4, the axis of which is parallel with, but eccentric with respect to, the axis of the roller. By moving this core nearer to or farther from the wall of the chamber P, the circulation of the fluid can be restricted in the region 18 and cooling of the adjacent parts of the roller is lessened. Instead of using a solid core 17, a tube may be used through which cooling- fluid is circulated, the adjacent parts of the roller being cooled by radiation. The tube may be coaxial with the roller, one or more movable screens being arranged between the tube and the roller. The cooling-fluid may be admitted to the roller by a perforated tube 23, Fig. 6, the position of which is adjustable. The fluid issuing in jets strikes the wall of the roller, and the cooling-effect is local and varies with the position of the tube 23. In another arrangement, shown in Fig. 7, a movable screen 26 is used which reduces the cooling-action on the part covered. The screen may be provided with projections or depressions to affect the flow of the fluid. In a further arrangement, cooling is effected by metal brushes, some of the " bristles " 28, Fig. 9, being closer to one another to vary the cooling-effect. A screen or shield, similar to the screen 26, may be used in connection with the brushes. The Specification as open to inspection under Sect. 91 states that the invention may be applied to the rotary moulds used for the centrifugal casting of pipes. This subjectmatter does not appear in the Specification as accepted.