Patent GB-389923-A (GB)
Title: Improvements in or relating to glass feeding devices
IPC: C03B7/08
Filed: 1931-12-11
Abstract: 389,923. Glass manufacture. WOOD, J. T., 21, Duffield Road, Pendleton, near Manchester. Dec. 11, 1931, No. 34329. [Class 56.] A feeder of the reciprocating- plunger type is provided with means for keeping the glass in the forehearth at a uniform temperature, means for supporting the plunger so that it can be removed or centred readily, and means for operating the plunger so that charges of glass of different weights can be delivered in predetermined succession. The forehearth 4, Fig. 2, is provided with a flow channel as described in Specification 213,406, [Class 56, Glass], and the forward end of the channel is formed with a depression 3 in which there is an elevated portion 7. The glass flowing along the channel is forced to flow around the portion 7, although part of the glass flows over it, and the flow is more evenly distributed around the plunger 18. The plunger rod 19, Figs. 2 and 5, has a slide 21 secured to its lower end, and a holder 22, which fits on the part 21, has a slide 23 formed on its underside, the two slides being at right-angles to one another. Another holder, 24, fits on to the slide 23 and supports the plunger 18 by means of pivoted clamping- levers 28. By adjustment of the holders 22, 24 along the slides, the plunger 18 can be centred in relation to the outlet aperture 1, the holders then being locked in place by means of screws 46, 48. The levers 28 are caused to grip the plunger 18 by means of screws 33 or springs 40 which force the upper ends 31 of the levers outwards. In a modified construction, a single holder is employed which fits over, and is movable in relation to, a plate secured to the lower end of the rod 19. In order that the feeder may deliver charges of different weights, means are provided for altering the stroke of the plunger 18 automatically. The plunger is reciprocated by a pneumatic cylinder 62, Fig. 2, and its downward movement is limited by a sleeve 59 which slides over the piston rod 61 of the cylinder and co-operates with a fixed stop 75 secured to the rod 61. The sleeve 59, which forms an adjustable stop, is screw threaded externally and is prevented from rotating by a key carried by a bracket 60. A bevel wheel 63, screwed on to the sleeve 59 and journalled in a bracket 64, is geared to a vertical shaft 70, Fig. 9, to which a hand-wheel 71 and a pinion 76 are secured. The hand-wheel enables the bevel wheel 63 to be rotated, and thus, by raising or lowering the sleeve 59, shortens or lengthens the stroke of the plunger. The pinion 76 is engaged by a rack 77 which is reciprocated by a pneumatic cylinder 79. The movement of the rack raises or lowers the sleeve 59, and thus enables charges of glass of two different weights to be fed alternatively by the plunger. The stroke of the rack is adjustable by means of stops 86, 85 to regulate the weight of the charges of glass. An adjustable stop 97, Fig. 2, which regulates the upward movement of the plunger, may also be operated by mechanism similar to that shown in Fig. 9. In a modified construction, the sleeve 59 is dispensed with and the piston rod 61 is made in two parts which are moved relatively to one another by the bevel wheel 63. In order to keep the temperature of the glass between two predetermined limits, means are provided for raising or lowering a damper 110 between the furnace 135 and the forehearth, for moving a damper 111 in the flue 112 through which burnt gases escape, and for altering the supply of air to the burners that heat the forehearth. The temperature is indicated or recorded by any usual type of pyrometer, which can be arranged to close one electric circuit and open another when indicating either the lower or upper limit of temperature. The circuits include two solenoids which move a valve that controls the supply of gas and air to the burners, and also the supply of air to a cylinder 109 for moving the damper 111, and to a cylinder that raises and lowers the damper 110. Specification 229,804, [Class 56, Glass], also is referred to.