Apparatus and method to control gob weight, length and/or shape

A control arrangement for controlling a system for producing gobs for an individual section machine having a plurality of sections including at least a first section and at least a second section, the system cyclically producing a set of gobs including at least one gob for each of the plurality of sections including at least one first gob for the first individual section and at least one second gob for the second individual section, wherein each gob has a predetermined first physical characteristic value, the system producing gobs including:

• (1) a gob feeder apparatus and (2) a gob shearing mechanism, the gob feeder apparatus having:
• (A) a spout bowl with at least one discharge orifice hole located in the bottom thereof;
• (B) a cylindrical feeder tube within the spout bowl;
• (C) a cylindrical feeder tube vertical adjustment arrangement for adjusting the vertical offset of the cylindrical tube feeder relative to the bottom of the spout bowl;
• (D) at least one plunger needle located within the feeder tube above the at least one discharge orifice hole;
• and (E) a drive arrangement operably coupled to the at least one plunger needle to reciprocally drive the plunger needle toward and away from the discharge orifice hole to emit at least one molten glass stream, the gob shearing mechanism having a reciprocating shear blade located below the spout bowl to repeatedly cut the at least one molten glass stream emitted from the discharge orifice hole to form the gobs that form the set of gobs, the control arrangement comprising:
• a controller configured to cyclically control, based on a set of feeder control settings for forming the set of gobs:
• A) actuation of the drive arrangement to reciprocally drive the at least one plunger needle towards and away from the discharge orifice hole;
• B) actuation of the reciprocating shear blade;
• and
• C) actuation of the cylindrical feeder tube vertical adjustment arrangement to control a vertical offset of the cylindrical feeder tube relative to the bottom of the spout bowl;
• the controller being configured to determine the set of feeder control settings by determining and using an optimal and feasible set of feeder control setting deviations which is a set of deviations from a set of predetermined nominal feeder control settings;
• wherein a magnitude of each feeder control setting deviation has a deviation magnitude range of between zero deviation and a maximum deviation from the corresponding nominal feeder control setting;
• wherein the feeder control setting deviations have a predetermined priority order from lowest priority to highest priority;
• wherein the optimal and feasible set of feeder control setting deviations is feasible if the set of feeder control settings that are determined using the optimal and feasible set of feeder control setting deviations will create the set of gobs with each gob having the corresponding predetermined first physical characteristic value and is optimal if a magnitude of any one of the feeder control setting deviations within the set of feeder control setting deviations is reduced, a magnitude of a feeder control setting deviation having a lower priority must be increased for the set of feeder control setting deviations to be feasible.