Patent GB-275169-A (GB)
IPC: C03B25/08
Filed: 1927-05-18
Abstract: 275,169. Pittsburgh Plate Glass Co., (Assignees of Heichert, H. S.). July 29, 1926, [Convention date]. Charges, conveying; indicators. -Apparatus for making sheet glass comprises rolling means for forming the molten glass into sheets at relatively high speed and an annealing leer for receiving the sheets provided with transporting rollers arranged in separately driven groups which at the forward end of the leer are driven at high speed until the sheet is sufficiently set, after which they are driven at a reduced speed corresponding to the speed of the rollers in the rear section of the leer. Indicating means governed by the sheets are provided for informing the operator of the position of the end of the sheets as they pass through the forward section of the leer. The rolling apparatus comprises a shell 1, Figs. 1 and 2, supported on driving-rollers 5, 6 and a sizing roller 2 driven through interconnected gearing from a shaft 47. Glass is poured into the recess between the shell 1 and roller 2 and is delivered in sheet form over a water-cooled apron 16 on to a separately driven group of rollers 18 and then on to the rollers of the leer 17 which are arranged in separately driven groups 19 - - 28, Figs. 2, 2<a>. The rollers in the section A<1> of the leer are all driven at high or low speed. Those in the section A<11>, Fig. 2a, are all driven at high or low speed or with some groups at high speed and others at low speed while the rollers in the section B are all driven at low speed. The driving gear for the rollers consists of a longitudinal shaft consisting of a section 39, Fig. 1<a>, driven by a motor 38 at low speed and extending throughout the length of the rear section of the leer, the shaft being coupled to the groups of rollers through gearing. The shaft 39 is coupled to shaft sections 42 - - 47, Figs. 1, 1<a>, by a roller clutch 43a and combined roller and electromagnetic clutches 50 - - 54 so that the whole of the shafting may be driven at slow speed, while a high speed motor 37 coupled to the shafting at the forward end of the leer enables the shaft sections 42 - - 47 to be driven at high speed. The rollers in the forward end of the leer are driven by sprockets 30 and sprocket chains 29 from the forward shaft sections. The rolling and conveying operations are effected as follows. Assuming that the slow speed motor 38 is driving the leer rollers and rolling apparatus at slow speed, glass is poured into the recess 3 and the starting button 92, Fig, 10, is pressed to complete the circuit from the mains 96, 97 through the lines 98 - - 100 to the high speed motor 37. Simultaneously the electromagnetic clutch 54 is energized through the lines 110, 111 and switch 112 and the shafts 46, 47 driven at high speed and likewise the rolling apparatus and groups of rollers 18 - - 22, Fig. 2. An electromagnetic clutch 119 on one of the rollers 18 is also energized through the lines 110, 111 to transmit motion to a shaft 72 and rotate the arm 73 of the indicator The sheet of glass is carried at high speed over the groups of rollers 18 - - 22 and upon the forward edge of the sheet reaching the groups of slow moving rollers 22 - - 26 each group is caused successively to rotate at high speed. This is effected by the rotating arm 73 which operates switches 74 - - 77 successively as the sheet reaches each successive group of rollers and effects the closing of switch arms 122, 132, 133, 134 to complete circuits for energizing the clutches 50 - - 53 and coupling the shafts 42 - - 45 to the high speed shaft 46. The sheet is completely generated when its leading edge reaches the roller 27 in the slow speed section B of the leer and may be slowed down in speed. The arm 73 now operates the switch 78 and breaks the circuit of the motor 37 through the lines 120, 121, 99, 100, and after a short interval operates the switch 79 and breaks the circuit of the clutches 50 - - 54, the lines 116, 117 being interrupted and the winding 113 releasing the arm 112 and breaking the circuit between the return line 126 and line 97. The operator is informed of the position of the ends of the sheets by means of lamps 101 - - 105 which are illuminated and extinguished as the forward and rear ends of the sheet pass under switches 32 - - 36 adapted to open and close the circuits of an alternating current line 106, 107. Specification 269,300 is referred to.