GB849197A - Methods of corrugating sheets of asbestos cement or the like and corrugating machines suitable for carrying out the methods - Google Patents

Abstract

849,197. Corrugating asbestos-cement sheets. SMIDTH & CO. A. S., F. L. June 15, 1959, No. 20492/59. Class 87(2). Sheets of asbestos cement are corrugated, while plastic, in a machine which comprises an upper member 7 with a working surface conforming to the required corrugations and a lower member 8 with rollers A, B, C, D conforming to the valleys of the upper member and carried on the upper ends of pistons 12 of compressed air cylinders 13. The middle roller A is first raised to press the middle part of the sheet into the correspondihg valley and the remaining rollers B-B, C-C, D-D are moved in succession to complete the corrugation. Compressed air is distributed to the cylinders by a known device 15 operated automatically by a rod 18. To reduce friction and lessen the risk of the sheet cracking as it is corrugated, chains 35, 36, fixed at one end to the support 37 of the roller A pass round sprocket wheels B 1 , C 1 , D 1 on the shafts of the rollers B, C, D and round sprocket wheels ba, ab &c. on shafts carried by the framework and terminate in weights or springs 37, 38, the operation being that when the roller A rises, the remaining rollers are positively rotated in the direction of the movement of the sheet, the same rotation being imparted to the remaining rollers when the rollers B 1 C 1 and D 1 are raised. The upper moulding member 7 is hollow and when all the rollers are pressing against it, i.e. when the corrugation is complete, a valve 20 in a partly flexible pipe 19 is set to connect it to a source of vacuum and the sheet 9 thus remains on its lower surface when the rollers are lowered. The moulding member 7 is suspended in a carriage 21 which is pushed, along rails 23, above a table 28, and a valve 26 is then actuated to cause the piston-rod 25 of a cylinder 24 to deposit the sheet, the valve 20 being simultaneously actuated to connect the moulding member 7 to atmosphere. By a similar operation a vacuum pick-up device 29, raised and lowered by a cylinder and piston 40, 39 and connected to vacuum or atmosphere through a pipe 31, picks up a fresh sheet from a conveyer 33 and deposits it on the rollers of the lower member 8.