GB847892A - Improvements in or relating to the separation of sections from a ribbon of glass - Google Patents

Abstract

847,892. Glass cutting. PILKINGTON BROS. Ltd. Nov. 17, 1958 [Nov. 26, 1957], No. 36968/58. Class 56. For ease in altering the length of sections to be cut from a continuous ribbon of glass as'it issues from a drawing apparatus, two or more stops are disposed at predetermined intervals along the path of the leading end of the ribbon and each stop is movable into and out of the path and is adapted on engagement by the leading end of the ribbon to initiate a cut starting signal for effecting operation of a cutting device by which the ribbon is scored automatically along a line about which the section is separated from the ribbon ; the stops being moved simultaneously to a position at which one of the stops is spaced from the cutting device by the required length of the next section and only said one stop is caused to be capable of initiating a cut starting signal when engaged by the leading end of the ribbon. As shown with a fixed cutter bar 63 set at an angle, as in Figs. 1 and 7, a bracket 3 and housing 4 is secured to the top of a drawing frame 1 through which the continuous ribbon 2 of glass rises. A setting nut 7, which slides in a guide 5 secured to housing 4, has a threaded opening engaging a screw 8 integral with a driving shaft in housing 4, and a cavity 16 to support the lower end of a tube 9, the screw 8 and tube 9 being maintained parallel to the guide 5 as by bearings 10 and sleeves 11, 12, 13. Two or more stops 17a, 17b are secured on the tube 9 by brackets 18 and are at fixed distances, such as 1 metre apart, rotation of screw 8 allowing adjustment of stop 17a for any distance from the cutting device up to 1 in., of stop 17b for any distance between lin and 2 in. and so on. The screw 8 is threaded at the same rate as a scale 20, e.g. one turn per centimetre, and a disc 21 in millimetres is fixed on the screw 8 so that rapid rotation of screw 8 brings a portion 19 on the nut 7 against the number of centimetres required and the screw 8 is then rotated a fraction of a turn to bring an index 22 against the graduation on the disc 21 to give the length to the nearest millimetre or tenth of a millimetre. Each stop 17a, 17b comprises angle iron stop 33 pivoted at 52 to a plate 30 pivoted by lugs 28<SP>1</SP>, 36 to the non- threaded ends of a threaded rod 27 screwed through flanges 25<SP>1</SP>, 25<SP>11</SP> on the bracket 18 and having a manipulating rod 37<SP>1</SP> for fine adjustment of the stop 33 if not agreeing with the indices 19 and 22. The stop 33 carries two normally open switches 41, 42, the buttons 43, 44 of which are operated by an actuator 45 slidably suspended in the stop 33 and having a board 46 to be engaged by the leading end of the glass ribbon. A magnet 53 normally holds the stop 33 horizontal with the heel 40 against an adjustable screw 39, the glass ribbon closing the contacts 41, 42 before overcoming the action of magnet 53 to pivot the stop 33. A two speed reversible electric motor and reduction gear are used to effect movements of the stops 17a, 17b as necessary, a crank on the shaft of the motor permitting manual operation, and a selector switch in the circuit to the cutting device brings the selected stop into operation to control the device. For use with a moving cutting device, which may be as described in Specification 690,262, the housing 4, column 5, screw 8, setting nut 7 and tube 9 are fixed to a movable frame 105, 107, 111, Fig. 11, which normally rests on the main frame 1 and has rollers 108 rolling on rails 109 fixed to the frame 1, the movable frame 105, 107, 111 supporting the cutter carriage 104 which has rollers 106 mounted on the rail 105 which is horizontal and parallel to the ribbon of glass 2. The frame 105, 107, 111 is suspended by cables 115, with counterweights 114, passing over pulleys 116 on a rigid shaft 123. In this embodiment, the stops 113<SP>1</SP>, 113<SP>11</SP> are pivoted at 1251, 125<SP>11</SP> to. sleeves 124<SP>1</SP>, 124<SP>11</SP> on the tube 9, each sleeve also having an arm 127<SP>1</SP>, 127<SP>11</SP> which supports a catch 1261, 126<SP>11</SP> to engage the stop and a roller 1281, 128<SP>11</SP> for realeasing the catch on engagement by a counter stop 1291, 129<SP>11</SP> fixed adjustably on a vertically movable rod 76. The lower end of rod 76 is formed with a screw 82 which engages a rotatable threaded sleeve 84 keyed to a toothed wheel 87 rotating in an extension 88 of the housing 4 and meshing with a pinion 89 actuated from the screw 8 so that the counter stops 129<SP>1</SP>, 129<SP>11</SP> are adjusted at the same time as the stops 113<SP>1</SP>, 113<SP>11</SP>. Each stop carries contacts 41a, 42a and 41b, 42b for controlling the motor of the cutting device and a third contact 75<SP>1</SP>, 75<SP>11</SP> to control a solenoid 701, 70<SP>11</SP>, the armature 71<SP>1</SP>, 71<SP>11</SP> of which is pivoted to the catch 126<SP>1</SP>, 126<SP>11</SP> so that only the operative stop is held by the catch until released by its counter stop 129<SP>1</SP>, 129<SP>11</SP>. This embodiment is also shown for use with a horizontal drawing apparatus.