Patent GB-543751-A (GB)
Title: Apparatus for forming hollow glassware
IPC: C03B9/18
Filed: 1940-09-10
Abstract: 543,751. Making hollow glassware. BRIDGES, E. G. Sept. 10, 1940, No. 14053. [Class 56] Relates to a machine for blowing hollow glassware, in which a number of parison moulds are moved in succession to compacting, counterblowing, mould-opening, and re-heating positions. According to the invention, the counterblowing of a parison in a parison mould is continued while the mould moves through a distance substantially greater than the spacing between successive moulds. Figs. 2 and 3 show a double-table machine, of the kind described in Specification 386,012, in which the mould tables 10, 11 are each provided with its own driving-mechanism comprising a Geneva wheel 19 that is housed in a deep well 15 in the machine base and is rotatable on a vertical column 12, 13 respectively. A rotator 30 for each Geneva wheel is journalled in anti-friction bearing 31 and carries a worm wheel 36 driven by a worm 37, the driving member and the worm wheel being removable from the well as a unit. The worms 37 are coupled to a shaft driven by a motor 50, Fig. 6, through a variablespeed gear and an overload clutch that permits the machine to stop if subjected to an excessive load. Another clutch in the drive can be operated by a pneumatic cylinder 86 or a hand lever 85 to stop the machine. Each mould table is also provided with a brake drum 327 encircled by braking-shoes 325 operated by a pneumatic cylinder 331. The brakes are applied during the last half of the movement as the table moves from one operating position to the next. The driving-mechanism also rotates a shaft for synchronizing the operation of a feeder with the forming-machine, and also a timing device 275 for timing the operation o the machine. This device consists of a vertical drum with circumferential slots in which are adjustably secured buttons that operate valves controlling the supply of compressed air to pneumatic cylinders. The parison moulds, secured to holders 102, Fig. 2, are inverted to receive charges of molten glass and are operated as described in Specification 386,012. At the charging position, the neck end of the mould is closed by a mouthforming pin 134 which is moved'into and out of the mould by a stationary pneumatic cylinder 141 the piston rod of which has a yoke 142 that engages the lower end of the mouth-forming pin. Suction is applied, to compact the charge in the mould, by a suction head 145 which is moved by a pneumatic cylinder 148 into contact with an opening in the housing 130 of the neck-forming pin. The piston of the cylinder 148 also carries a suction valve casing 150 which comprises a valve for connecting the blowhead 145 to the suction chamber, and a pneumatic cylinder 156 for opening and closing the valve. The compacting of the glass may be assisted by air pressure applied to the upper end of the charge of glass. For this purpose, a blowhead 160 is attached to a shaft 162 which is raised and lowered by a pneumatic cylinder 165, and is also provided with a roller 166 which engages on an inclined cam track 167 and causes the blowhead to swing to one side as it is raised from the open end of the mould. During the movement of the mould to the next operating position, a baffle plate is applied to the open end of the mould and the charge of glass is counter-blown, or expanded to fill the mould, by compressed air applied through the neck pin housing 130. According to the invention, the counter-blowing is sustained through a relatively long period and takes place during the movement of the mould from the stop at 'the end of the compacting operation until the next stopping position or even to the following position. Initiation of the counterblowing period is effected by an adjustable pin 192, Fig. 2, which operates a rocker valve 180 that admits air to the housing 130. The valve is connected to a combined air and lubricant cup surrounding the column 12. The valve is closed by the stroke of a pneumatic cylinder which may be operated to finish the counter-blowing as the mould approaches or leaves a stopping position, as required. The moulds are reverted, partly opened to allow the parison to re-heat, and the parison is then transferred to a finishing mould, the construction of the finishing mould mechanism being similar to that described in Specification 386,012. Specifications 508,021 and 508,056 also are referred to.