GB307822A - Improvements in and relating to paper making machines - Google Patents

Abstract

307,822. Butterworth, F., and Horsburgh, R. W. March 14, 1928, [Convention date]. Thickness of paper, regulating and gauging; pulp, regulating flow and consistency of.-Light sensitive cells or mechanical or electromechanical means are used to detect the changes in the thickness of paper during its manufacture in the paper machine and with or without amplifiers or relays the means are used to adjust, automatically either the speed of the machine or the valve of the stuff chest to maintain the correct thickness or weight of paper. In the apparatus illustrated, the paper web P, Fig. 2, during manufacture passes beneath a source of light 23 backed by a reflector 26 and the light passing through the paper is focused by lenses 28, 29 on to a cell sensitive to light rays such as a selenium or photo-electric cell 31, which, with a galvanometer 33, Fig. 1, and transformer 34 is in the circuit of a battery 32. An amplifier 35 comprises a fixed solenoid 41, Fig. 3, and a core 43 carrying a roller or slide 44 insulated therefrom. This roller normally rests between two contacts 48, 49 on a block 50. Variation in the thickness or weight of the paper during manufacture moves the core 43, and the roller 44 makes contact with one or other of the contacts 48, 49 thus completing the circuit of the motor 55 which, through gearing 58 moves a contact 60 over studs 61 of a rheostat in the shunt circuit of a motor 9 and adjusts the speed of the paper machine driven thereby. The motor 55, through gearing 56 also rotates a screw 51 and thus slides along the block 50 until the roller 44 is in the mid position between the contacts 48, 49, thus stopping the relay, leaving the rheostat adjusted to the new position. Instead of the fixed coil 41, a moving coil may be used and the motion of the coil may operate a dependent arm immersed in a liquid resistance in the circuit of the motor driving the paper machine. The motor 55 may be used to rotate the brushes of a variable speed alternating current motor which may be used in place of the motor 9. The relay may be used to operate an auxiliary stuff cock by which pulp is supplied to the paper machine. Where steam or internal combustion engines are used as prime movers, the motor 55 may be used to control steam or gas valves, governors &c.