System and method for measuring glass temperature during tube transition

Abstract

A system for producing articles from glass tubes includes a converter having a base having a plurality of processing stations and a turret movable relative to the base. The turret continuously aims and moves a plurality of holders for holding the glass tubes through the processing stations. The system further includes a thermal imaging system including a thermal imager coupled to the turret so as to move with the turret. The thermal imaging system may also include a reflector coupled to the thermal imager and positioned to reflect infrared light from one of the plurality of holders toward the thermal imager. The thermal imaging system may measure one or more characteristics of the glass tube during the conversion process. A method of using the thermal imaging system to measure one or more process variables to control the converter is also disclosed.

Description

[0001] Divisional Application Instructions

[0002] This application is a divisional application of an invention patent application with an application date of March 22, 2018, an international application number of PCT / US2018 / 023873, a national application number of 201880020806.3 after entering the Chinese national phase, and titled "System and method for measuring glass temperature during tube conversion".

[0003] Related Applications Cross Reference

[0004] This application claims the benefit of priority under 35 U.S.C. §120 to U.S. Provisional Application No. 62 / 476,408, filed on March 24, 2017, entitled “SYSTEM AND METHOD FOR MEASURING GLASS TEMPERATURE DURING TUBE TRANSFORMATION,” the entire contents of which are incorporated herein by reference.

[0005] background

[0006] field

[0007] The present description generally relates to systems and methods for measuring glass temperature during conversion of a glass tube into a glass product. Technical Background

[0008] Glass tubing can be converted into other glass products. For example, glass tubing can be converted into a variety of glass containers (including but not limited to vials, syringes, ampoules, barrels and other glass products) for use in pharmaceutical applications. Glass tubing can be converted, for example, in a "converter." Converters have been used for more than 75 years and are currently manufactured by a variety of commercial and in-house equipment suppliers. These converters generally use steps including flame machining, rotating and stationary tool forming, thermal separation or scoring, and impact cutting steps to transform long lengths of glass tubing into multiple glass products.

[0009] In the current glass converting industry, converting machines are run by operators and technicians with extensive experience. These operators and technicians learn machine operation through experience and craftsman-like training, and operational adjustments such as burners and machine settings are generally performed only by visually assessing the temperature and shape of the partially formed or fully formed glass product. Operating practices and machines are further tightly controlled by component manufacturers, a practice that poses a substantial barrier to new manufacturers entering the market for producing high-end pharmaceutical products.

[0010] Accordingly, a need exists for alternative systems and methods for forming glass articles using tube conversion machines.

[0011] Overview

[0012] Accordingly, a need exists for a system and method for measuring the temperature of a glass tube during its transition to produce a glass article.

[0013] In one or more aspects of the present disclosure, a system for producing a glass article from a glass tube may include: a converter including a base having a plurality of processing stations spaced apart from one another in a loop; and a turret movable relative to the base, the turret having a plurality of holders extending from the turret toward the plurality of processing stations, the plurality of holders spaced apart from one another, wherein the turret may be used to index each of the plurality of holders sequentially into proximity with each of the plurality of processing stations. The system may further include a thermal imaging system including a thermal imager coupled to the turret so as to move with the turret, wherein the thermal imager is positioned to capture infrared light emitted from the glass tube disposed in one of the plurality of holders.

[0014] In some embodiments, the thermal imager may be positioned to directly receive infrared light emitted by the outer surface of the glass tube. The thermal imaging system may further include at least one reflector oriented to reflect infrared light emitted from the inner surface of the glass tube toward the thermal imager. The at least one reflector may be a stationary reflector coupled to the base and oriented to reflect infrared light emitted from the inner surface of the glass tube toward the thermal imager.

[0015] In some embodiments, the system may further include a reflector coupled to the thermal imager and oriented to reflect infrared light from the glass tube toward the thermal imager. The reflector may be oriented to reflect infrared light emitted from the outer surface of the glass tube toward the thermal imager. The reflective surface of the reflector may have a reflectivity equal to or greater than 96% for light having a wavelength from 800 nanometers to 20 microns. In other embodiments, the reflector may be oriented to reflect infrared light emitted from the inner surface of the glass tube toward the thermal imager.

[0016] In some embodiments, the system may include at least one supplemental reflector coupled to the thermal imager, wherein the reflector is oriented to reflect infrared light emitted from the outer surface of the glass tube toward the thermal imager and the supplemental reflector is oriented to reflect infrared light emitted from the inner surface of the glass tube toward the thermal imager. In other embodiments, the system may include at least one stationary reflector vertically positioned below one of the plurality of processing stations, the stationary reflector being positioned to reflect infrared light emitted from the inner surface of the glass tube toward the thermal imager when the thermal imager is aimed and moved into position by the turret at the one of the plurality of processing stations.

[0017] In some embodiments, the thermal imager may be an infrared camera configured to receive infrared light having a wavelength from 4 microns to 14 microns or from 5 microns to 14 microns. In some embodiments, the system may include a main turret and a secondary turret. The thermal imager may be coupled to the main turret so as to rotate with the main turret. The system may include a loading turret positioned above the main turret and rotatable relative to the main turret. In some embodiments, the thermal imaging system may include a plurality of thermal imagers.

[0018] In certain embodiments, the system may include a slip ring positioned above the turret and having a slip ring shaft aligned with a central axis of the turret, the slip ring electrically coupling the thermal imager to a power source. The slip ring may operatively couple the thermal imager to a processor. An inner ring of the slip ring may include a central hole.

[0019] In other embodiments, the system may further include a power supply coupled to the turret so as to rotate with the turret, the power supply being electrically coupled to the thermal imager to provide power to the thermal imager. The system may also include a wireless communication device coupled to the turret, wherein the wireless communication device communicatively couples the thermal imager to the processor.

[0020] In some embodiments, the system may include a cooling system including a cooling fluid supply, a rotating union fluidly coupled to the cooling fluid supply and having a union axis aligned with a central axis of the turret, and a supply conduit extending from the rotating union toward the thermal imaging system. The system may also include a cleaning system including at least one nozzle positioned to deliver fluid to a lens of the thermal imager. The thermal imaging system may include a reflector coupled to the thermal imager and oriented to reflect infrared light from a glass tube positioned in one of the plurality of holders toward the thermal imager, and the cooling system may include at least one nozzle positioned to deliver fluid to a reflective surface of the reflector.

[0021] In certain embodiments, the system may include: at least one processor, the at least one processor being communicatively coupled to the thermal imager; at least one memory module, the at least one memory module being communicatively coupled to the processor; and machine-readable instructions, the machine-readable instructions being stored in the at least one memory module, the machine-readable instructions, when executed by the at least one processor, causing the thermal imaging system to perform at least the following steps: receiving thermal imaging information from the thermal imager; processing the thermal imaging information; and determining a property of the glass tube from the thermal imaging information. The property may be at least one of a temperature of the glass tube, a temperature gradient across the thickness of the glass tube, a viscosity of the glass tube, a viscosity gradient across the thickness of the glass tube, a size of the glass tube, a temperature distribution of the glass tube, a temperature distribution of the glass tube as a function of time, a centerline of the glass tube, or a combination thereof.

[0022] In some embodiments, the system may further include machine-readable instructions stored in the at least one memory module, which, when executed by the at least one processor, cause the thermal imaging system to perform the following steps: determine the temperature of the glass tube from the thermal imaging information; determine the viscosity of the glass tube from the thermal imaging information; or determine the size of the glass tube from the thermal imaging information.

[0023] In certain embodiments, the system may further include machine-readable instructions stored in the at least one memory module, which, when executed by the at least one processor, cause the thermal imaging system to perform at least the following steps: determining a first characteristic of the glass tube at a first processing station; determining a second characteristic of the glass tube at a second processing station positioned downstream of the first processing station; calculating a difference between the first characteristic and the second characteristic; and transmitting an output representing the difference between the first characteristic and the second characteristic.

[0024] In certain embodiments, the processor may be communicatively coupled to a control device, and the system may further include machine-readable instructions stored in the at least one memory module, which, when executed by the at least one processor, cause the thermal imaging system to perform at least the following steps: comparing the characteristic of the glass tube with a setpoint characteristic; determining a controlled variable from the comparison of the characteristic of the glass tube with the setpoint characteristic; and transmitting a control signal representing the controlled variable to the control device.

[0025] In some embodiments, at least one of the plurality of processing stations may include a heating station having at least one heating element, and the control device is operatively coupled to the heating element to manipulate the heating of the glass tube by the heating element. The heating element may include a burner, and the control device may be one or more of a fuel control valve, an oxygen control valve, or an air control valve. The controlled variable may be a mass flow rate of one or more of the fuel gas, oxygen, or air. Alternatively, the controlled variable may be a position of one or more of the fuel control valve, the oxygen control valve, or the air control valve.

[0026] In some embodiments, at least one of the processing stations may be a cooling station having at least one cooling fluid control valve, wherein the control device is the cooling fluid control valve. In some embodiments, at least one of the processing stations may be a forming station having one or more actuators that displace at least one forming tool into removable engagement with the glass tube, wherein the control device includes the one or more actuators. The controlled variable may be the contact time of the at least one forming tool with the glass tube in the forming station.

[0027] In certain embodiments, the system may further include a sizing system. The sizing system may include at least one of a visual imaging system, a laser reflectometer, a laser measuring instrument, or an optical micrometer. The sizing system may be positioned to capture measurement data of the glass tube upstream of the converter. Alternatively, in certain embodiments, the sizing system may be positioned to capture measurement data of the glass tube at one of the plurality of processing stations. The system may further include machine-readable instructions stored in the at least one memory module, which, when executed by the at least one processor, cause the sizing system to perform at least the following steps: capture measurement data of the glass tube in the one of the plurality of processing stations; process the measurement data of the glass tube; and determine a physical property of the glass tube from the measurement data of the glass tube. The physical property is one or more of a diameter, a thickness, or a mass of glass per unit length of the glass tube.

[0028] In certain embodiments, the system may include machine-readable instructions stored in the at least one memory module, which, when executed by the at least one processor, cause the system to perform at least the following steps: receiving the physical property of the glass tube from the sizing system; and determining a property gradient across the thickness of the glass tube from the physical property and the property. The property gradient may be a temperature gradient or a viscosity gradient.

[0029] In some embodiments, the system may include machine-readable instructions stored in the at least one memory module, which, when executed by the at least one processor, cause the system to perform at least the following steps: comparing the physical property of the glass tube with a set point physical property; and determining an adjustment to the controlled variable from the comparison of the physical property of the glass tube with the set point physical property.

[0030] In another aspect, a method for controlling a glass tube converter may include the steps of aiming a glass tube to move through a plurality of processing stations of the glass tube converter, the glass tube being removably coupled to a turret of the glass tube converter, at least one of the plurality of processing stations comprising a control device. The method may further include the steps of capturing a thermal image of the glass tube using a thermal imaging system coupled to the turret of the glass tube converter, the thermal imaging system comprising at least a thermal imager oriented to capture infrared light from the glass tube. The method may further include the steps of processing the thermal image; determining a characteristic of the glass tube from the thermal image; comparing the characteristic of the glass tube to a set point; determining a controlled variable from the comparison of the characteristic of the glass tube to the set point; and transmitting a control signal representative of the controlled variable to a control device.

[0031] In certain embodiments of the method, at least one of the plurality of processing stations may include a heating station having at least one heating element, and the control device may be operably coupled to the heating element. The heating element may be a burner, and the control device may be one or more of a fuel control valve, an oxygen control valve, or an air control valve, wherein the controlled variable may be a mass flow rate of one or more of the fuel gas, oxygen, or air. The control device may be one or more of a fuel control valve, an oxygen control valve, or an air control valve, and the controlled variable may be a position of one or more of the fuel control valve, the oxygen control valve, or the air control valve.

[0032] In some embodiments of the method, at least one of the processing stations may include a cooling station having at least one cooling fluid control valve, wherein the control device may be the cooling fluid control valve. In certain embodiments of the method, the at least one of the processing stations includes a forming station having one or more actuators that displace at least one forming tool into removable engagement with the glass tube, wherein the control device may be the one or more actuators. The controlled variable may be the contact time of the at least one forming tool with the glass tube in the forming station.

[0033] In certain embodiments, the converter may include a sizing system having at least one of a visual imaging system, a laser reflectometer, a laser measuring instrument, or an optical micrometer positioned to capture measurement data of the glass tube at one of the plurality of processing stations. The method may further include the steps of: capturing the measurement data of the glass tube in the one of the plurality of processing stations; processing the measurement data of the glass tube; and determining a physical property of the glass tube from the measurement data of the glass tube. The physical property may be one or more of a diameter, a thickness, or a glass mass per unit length of the glass tube.

[0034] In some embodiments, the method may further include the steps of: comparing the physical property of the glass tube with a set point physical property; and determining the adjustment to be made to the controlled variable from the comparison of the physical property of the glass tube with the set point physical property. In other embodiments, the method may further include the steps of: measuring a physical property of the glass tube, wherein the physical property may be one of the diameter, thickness, or mass of the glass tube per unit length of the glass tube; comparing the physical property of the glass tube with a set point physical property; and determining the adjustment to be made to the controlled variable from the comparison of the physical property of the glass tube with the set point physical property.

[0035] It is to be understood that both the foregoing general description and the following detailed description describe various embodiments and are intended to provide an overview or framework for understanding the nature and character of the claimed subject matter. The accompanying drawings are included to provide a further understanding of the various embodiments and are incorporated into and constitute a part of this specification. The accompanying drawings illustrate the various embodiments described herein and, together with the description, serve to explain the principles and operation of the claimed subject matter. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 schematically depicts an embodiment of a converter for producing a glass article from a glass tube in accordance with one or more embodiments shown and described herein;

[0037] Figure 2 Schematically depicts a Figure 1 The main turret, auxiliary turret and feeding turret of the glass tube conversion machine;

[0038] Figure 3A Schematically depicts a Figure 1 Heating station for the converter;

[0039] Figure 3B Schematically depicts a Figure 1 Separation station for converters;

[0040] Figure 3C Schematically depicts a Figure 1 Forming station for converters;

[0041] Figure 3D Schematically depicts a Figure 1 Another embodiment of the forming station of the converter;

[0042] Figure 3E Schematically depicts a Figure 1 Cooling station for converters;

[0043] Figure 4 In accordance with one or more embodiments shown and described herein Figure 1 A perspective view of a glass tube before conversion in a converter;

[0044] Figure 5 Schematically depicts a Figure 1 Thermal imaging system with converter;

[0045] Figure 6 Schematically depicts a Figure 5 Thermal imaging system;

[0046] Fig. 7A Schematically depicts a Figure 5 Operation of thermal imagers of thermal imaging systems;

[0047] Figure 7B Schematically depicts a Figure 5 Operation of thermal imagers and stationary reflectors of thermal imaging systems;

[0048] Figure 7C Schematically depicts a Figure 5 Operation of thermal imagers and reflectors of thermal imaging systems;

[0049] Fig.7D Schematically depicts a Figure 7C Replacement operation of thermal imagers and reflectors of thermal imaging systems;

[0050] Fig. 7ESchematically depicts a Figure 5 Operation of thermal imagers, reflectors and supplementary reflectors of thermal imaging systems;

[0051] Figure 7F Schematically depicts a Figure 5 Operation of thermal imagers, reflectors and stationary reflectors of thermal imaging systems;

[0052] Figure 7G Schematically depicts a Figure 7F Alternative operation of thermal imagers, reflectors and supplementary reflectors of thermal imaging systems;

[0053] Fig. 8A Schematically depicts a Figure 1 Another embodiment of a thermal imaging system of a converter;

[0054] Figure 8B Schematically depicts a Figure 1 Another embodiment of a thermal imaging system of a converter;

[0055] Fig. 9 Schematically depicts a Figure 1 Another embodiment of a thermal imaging system of a converter;

[0056] Fig.10 For use with the converter 100 according to one or more embodiments shown and described herein Fig. 9 A plot of the relative temperature of the glass tube surface (y-axis) measured by a thermal imaging system as a function of time (x-axis);

[0057] Fig.11A According to one or more embodiments shown and described herein, Fig. 9 The image captured by the thermal imaging system depicts Figure 1 glass tubes in the heating station of the converter;

[0058] Fig. 11B According to one or more embodiments shown and described herein, Fig. 9 The image captured by the thermal imaging system depicts Figure 1 Glass tubes in the separation station of the converter;

[0059] Fig. 11CAccording to one or more embodiments shown and described herein, Fig. 9 The image captured by the thermal imaging system depicts Figure 1 glass tubes in a forming station of a converter;

[0060] Fig.11D According to one or more embodiments shown and described herein, Fig. 9 The image captured by the thermal imaging system depicts Figure 1 a glass tube in another forming station of a converter;

[0061] Fig.12 An image depicting the use of a Fig. 9 A thermal imaging system is used to capture the side view and top view of the glass tube in a single thermal image;

[0062] Fig.13 Schematically depicts a Figure 1 Control system of the converter;

[0063] Fig.14 Schematically depicts a Fig.13 Single feedback control method of control system;

[0064] Fig.15 Schematically depicts a Fig.13 Cascade control method of control system;

[0065] Fig.16 Schematically depicts a Fig.13 Another single feedback control method of the control system;

[0066] Fig.17 Schematically depicts a Figure 1 A cross-sectional view of a reflector of a thermal imaging system of a converter;

[0067] Fig.18A Schematically depicts a Figure 1 The secondary turret of the converter has a thermal imaging system; and

[0068] Fig.18B Schematically depicts a Figure 1Another embodiment of the secondary turret of the converter, the secondary turret has a thermal imaging system. Detailed Description

[0069] Reference will now be made in detail to embodiments of systems and methods for controlling a tube conversion process, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals will be used to refer to the same or like parts throughout the drawings. One embodiment of a system for producing articles from glass tubes is depicted in FIG. Figure 1 In this embodiment, a system for producing a glass article from a glass tube 102 includes a converter 100 and a thermal imaging system 120. The converter 100 includes a base 104 having a plurality of processing stations 106 separated in a loop and a main turret 108 separated from the base 104 and movable relative to the base 104. The main turret 108 includes a plurality of holders 130 extending from the main turret 108 toward the plurality of processing stations 106. The plurality of holders 130 are separated from each other, and each of the plurality of holders 130 is aligned with one of the plurality of processing stations 106. The main turret 108 can be used to continuously index each of the plurality of holders 130 to be proximate to each of the plurality of processing stations 106. The thermal imaging system 120 may include a thermal imager 122 that may be coupled to a portion of the main turret 108 so as to be displaced with the portion of the main turret 108. The thermal imaging system 120 may also include a reflector 124 that is coupled to the thermal imager 122 and positioned to reflect infrared light from one of the plurality of holders 130 toward the thermal imager 122. Various embodiments of systems and methods for controlling a tube switching process will be described herein with particular reference to the accompanying drawings.

[0070] Directional terms (eg, up, down, right, left, front, back, top, bottom) as used herein are made with reference only to the figures as drawn, and are not intended to imply an absolute orientation.

[0071] Unless otherwise expressly stated, no method described herein should be interpreted as requiring that its steps be performed in a particular order, or requiring a particular orientation when using any apparatus. Accordingly, if a method claim does not actually recite an order to be followed by its steps, or any apparatus claim does not actually recite an order or orientation of individual components, or does not otherwise specifically indicate in the claim or specification that the steps are to be subject to a particular order, or does not recite a particular order or orientation of components of an apparatus, then no order or orientation is to be inferred in any respect. This is true for any possible non-express basis for interpretation, including: matters of logic for arrangement of steps, operational flow, order of components, or orientation of components; inferences from the general meaning of grammatical organization or punctuation; and the number or type of embodiments described in the specification.

[0072] As used herein, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a" component includes aspects having two or more such components unless the context clearly dictates otherwise.

[0073] Now refer to Figure 1 , schematically depicts a converter 100 for producing glass products from a glass tube 102. The converter 100 can be used to convert the glass tube 102 into a plurality of glass products, such as, but not limited to, vials, syringes, barrels, ampoules, or other glass products. The converter 100 includes a base 104 having a plurality of processing stations 106, a main turret 108 positioned above the base 104 and rotatable relative to the base 104 about a central axis A, and a glass tube loading turret 110 positioned above the main turret 108 to feed the glass tube 102 to the main turret 108. The converter 100 may also include a plurality of secondary processing stations 112 on the base 104 and a secondary turret 114 that is rotatable relative to the base 104. A thermal imaging system 120 is coupled to the main turret 108 so as to rotate with the main turret 108. In some embodiments, the thermal imaging system 120 includes a thermal imager 122 and a reflector 124. A mounting device 126 may be used to couple the thermal imaging system 120 to the main turret 108. The thermal imaging system 120 may be used to capture thermal images of the glass tube 102 as the glass tube 102 is pointed and moved between the processing stations 106 using the main turret. From these thermal images, one or more temperatures or temperature profiles of the glass tube 102 may be extracted and used to study the conversion process and / or incorporated into one or more process control methods for controlling the converter 100.

[0074] like Figure 1, the base 104 of the converter 100 is stationary, and the processing stations 106 can be coupled to the upper portion 105 of the base 104. The plurality of processing stations 106 are spaced apart from each other and arranged in a main loop 116. In one or more embodiments, the main loop 116 can be circular so that the main turret 108 can be used to aim and move the glass tube 102 through the plurality of processing stations 106 by rotating the main turret about the central axis A. The type and / or shape of the article to be manufactured from the glass tube 102 can affect the number of processing stations 106 coupled to the base 104. The number of processing stations 106 of the main turret 108 can range from 14 processing stations 106 to 32 processing stations 106. Although the converter 100 and the conversion process are described in the context of the converter 100 having sixteen processing stations 106 in the main loop 116, it should be understood that the converter 100 can have more or fewer processing stations than sixteen processing stations 106 in the main loop 116. The processing stations 106 may include, by way of example and not limitation, one or more heating, forming, polishing, cooling, separating, perforating, measuring, feeding or unloading stations or other processing stations for producing glass articles from the glass tube 102. The type and / or shape of the article to be manufactured from the glass tube 102 may also affect the type of processing stations 106 of the converter 100 and / or the order of the processing stations 106.

[0075] The main turret 108 may be positioned above the base 104 and may be rotatably coupled to the base 104 such that the main turret 108 may rotate relative to the base 104 about a central axis A. A drive motor (not shown) may be used to rotate the main turret 108 relative to the base 104. The main turret 108 includes a plurality of holders 130 configured to removably secure each glass tube 102 to the main turret 108. The holders 130 may be clamps, fixtures, or other holding devices or a combination of holding devices. The holders 130 may orient each glass tube 102 such that the glass tube 102 is approximately parallel to the central axis A of the main turret 108 and approximately perpendicular to the upper portion 105 of the base 104. Although the converter 100 is described in this specification in the context of a vertically oriented converter 100, it should be understood that the converter 100 may be horizontally oriented or oriented at an angle. Each of the holders 130 is disposed from the bottom portion 109 of the main turret 108 in a direction toward the base 104 (i.e., in a direction relative to the Figure 1108 ) and each of the holders 130 is oriented to position the glass tube 102 in or near each of the successive processing stations 106 of the main loop 116 of the base 104 as the main turret 108 is pointedly moved about the central axis A. The vertical orientation of the glass tube 102 allows the downwardly protruding portion of each of the glass tubes 102 to be progressively cycled through the processing stations 106 of the main loop 116. Each of the holders 130 can be individually rotated relative to the main turret 108 about a holder axis D, which can be substantially parallel to the central axis A of the main turret 108. Each of the holders 130 can be operatively coupled to a motor (not shown), a continuous drive belt, or other drive mechanism for rotating each of the holders 130 relative to the main turret 108. Rotating the holders 130 allows the glass tube 102 to be rotated relative to a stationary burner, forming tool, cooling nozzle, or other feature of the processing station 106.

[0076] Reference Figure 1 and 2 , the converter 100 may have a plurality of secondary processing stations 112, which are also separated and arranged in a secondary loop 118 ( Figure 2 ) and auxiliary turret 114 ( Figure 1 ) so that the product 103 ( Figure 1 ) (which has been separated from the glass tube 102) is aimed and moved through the plurality of secondary processing stations 112. The secondary turret 114 can rotate about the second axis B relative to the base 104. The second axis B can be substantially parallel to the central axis A of the main turret 108. The secondary turret 114 also includes a plurality of holders 130 to hold the glass article 103 and to position the glass article 103 in sequence to engage with each of the secondary processing stations 112. The secondary turret 114 can be moved from the separation station 206 ( Figure 2 ) receives the product 103, moves the product 103 in an aimed manner through the multiple secondary processing stations 112 by rotating the secondary turret 114, and unloads the completed product from the converter 100.

[0077] The glass tube loading turret 110 is positioned above the main turret 108. In some embodiments, the glass tube loading turret 110 can be offset from the central axis A of the main turret 108. The glass tube loading turret 110 can rotate about an axis C, which can be substantially parallel to the central axis A of the main turret 108. The glass tube loading turret 110 can be independently supported in a stationary position relative to the main turret 108, and the rotation of the glass tube loading turret 110 can be independent of the rotation of the main turret 108. Figure 1 and 2In certain embodiments, the glass tube loading turret 110 may include a plurality of loading channels 132 arranged in a circular loop 134 and configured to hold the glass tubes 102. The glass tube loading turret 110 may be positioned to orient one of the loading channels 132 to be vertically aligned (i.e., parallel to and / or aligned with the central axis A of the main turret 108) with a corresponding holder 130 on the processing station 106 of the main loop 116 of the converter 100 and the main turret 108. Figure 1 The holder is aligned in a direction parallel to the Z-axis of the glass tube loading turret 110, and the holder is aimed at the processing station 106 moving through the main loop 116. In one or more embodiments, the processing station 106 aligned with the glass tube loading turret 110 can be a tube loading station 214 ( Figure 2 ). When the converter 100 has converted all or a portion of the glass tube 102 at a particular holder position 136 into one or more articles, the glass tube loading turret 110 can deliver a new length of glass tube 102 to the holder 130 at the holder position 136 through the top of the main turret 108 as the holder position 136 is aimed and moved to align with the tube loading station 214 of the main loop 116. In an alternative embodiment, the converter 100 may include an arm (not shown) that can be electromechanically moved between the main turret 108 and the glass tube loading turret 110. When the converter 100 has converted all or a portion of the glass tube 102 at a particular holder position 136, the arm can grab a new length of glass tube 102 from the glass tube loading turret 110 or other glass tube staging device and deliver the new length of glass tube 102 to the main turret 108 at the particular holder position 136. Other methods of delivering new lengths of glass tube 102 to main turret 108 are within the contemplated scope.

[0078] Reference Figure 2 As previously described, the plurality of processing stations 106 of the converter 100 may include one or more heating stations 202, forming stations 204, separation stations 206, polishing stations 208, cooling stations 210, perforating stations 212, tube loading stations 214, unloading stations 216, measuring stations 218, tube length drop stations 220, or other stations and / or combinations of these stations. Figure 2 The arrangement of the processing stations 106 of the converter 100 is schematically depicted, the converter having a primary loop 116 with sixteen processing stations 106 and a secondary loop 118 with eight secondary processing stations 112. As depicted, the processing stations 106 of the primary loop 116 are evenly spaced and evenly distributed around the circular loop, and the secondary processing stations 112 of the secondary loop 118 are also evenly spaced and evenly distributed around the circular loop. Figure 2 Also schematically depicted is a glass tube loading turret 110 having a plurality of loading channels 132. Figure 2 , for illustrative purposes, the glass tube loading turret 110 is illustrated in a position spaced apart from the main loop 116. Although the glass tube loading turret 110 is depicted as having twenty-four loading channels 132, it should be understood that the glass tube loading turret may have more or fewer than twenty-four loading channels 132.

[0079] Figure 2 The main circuit 116 of the converter schematically depicted in FIG. 1 may include one or more heating stations 202, a separation station 206, a flame perforation station 212, one or more forming stations 204, one or more cooling stations 210, a measuring station 218, a tube length delivery station 220, and a tube loading station 214. Relative to the direction 222 of the aiming movement of the main turret 108, the heating station 202 may be positioned before the separation station 206 and each of the forming stations 204 to preheat a target area of ​​the glass tube 102 to a target temperature at which the target area of ​​the glass tube 102 becomes plastically deformable and can be effectively shaped or cut without cracking or breaking the glass. At the separation station 206, the formed glass product 103 ( Figure 1 ) can be combined with glass tube 102 ( Figure 1 ) separation. The separation station 206 may also be a processing station 106 where the partially formed glass product 103, once separated, is transferred to the secondary turret 114 ( Figure 1 ) to aim the movement through the secondary loop 118 of the secondary processing station 112. The perforating station 212 can be positioned on the primary loop 116 downstream of the separation station 206 in the direction 222 of the aiming movement of the primary turret 108. At the perforating station 212, the end of the glass tube 102 previously closed by the separation station 206 is perforated, thereby forming an opening in the glass tube 102.

[0080] The forming station 204 of the main turret 108 may be positioned downstream of the perforating station 212 in the direction 222 of the aiming movement. At the forming station 204, the glass tube 102 is iteratively shaped into the desired finished glass product shape. As described above, one or more heating stations 202 may be positioned before each of the forming stations 204 to preheat a target area of ​​the glass tube 102 to a temperature at which the glass tube can be formed. The forming station 204 of the main turret 108 adjusts the shape of one end of the glass product 103, while the forming station 204 of the secondary turret 114 adjusts the shape of the other end of the glass product 103. In one or more embodiments, the converter 100 may be used to produce vials from the glass tube 102, and the forming stations 204 of the converter 100 may include one or more shoulder forming stations, one or more flange forming stations, and one or more flange finishing stations, wherein the one or more heating stations 202 are positioned before and between each of the forming stations 204. The main loop 116 may further include a measuring station 218, at which the sizing system 1310 ( Fig.13 ) can be used to measure one or more dimensions (e.g., diameter and thickness) of the glass tube 102 and one or more dimensions of features formed by the forming station 204. The feature dimensions can include flange thickness, flange length, neck length, neck thickness, overall article length, other feature dimensions, or combinations thereof. The measuring station 218 can be positioned directly after the last forming station 204 so that the dimensions are measured while the glass tube 102 is still at an elevated temperature. Alternatively, the measuring station 218 can be positioned after one or more cooling stations 210 to measure the dimensions of the glass tube 102 and / or glass article at a lower temperature.

[0081] Still refer to Figure 2 , one or more cooling stations 210 may be positioned after the forming station 204 in the direction 222 of the aiming movement of the main turret 108. A tube length delivery station 220 may be positioned after the forming station 204, between the forming station 204 and the separation station 206, to drop the partially formed glass tube 102, thereby positioning the glass tube 102 for cutting into a target length at the separation station 206. The main loop 116 may also include a tube loading station 214 to load new lengths of glass tubes 102 fed from the glass tube loading turret 110 into the main turret 108 ( Figure 1 In one or more embodiments, the tube loading station 214 can be incorporated into the cooling station 210. The tube loading station 214 can be positioned between the last forming station 204 and the separation station 206.

[0082] The forming station 204 of the primary turret 108 forms features at a first end of the glass article 103. For example, the forming station 204 may form a shoulder 142 and a flange 144 at the top (first end) of the glass article 103, which is a vial or a tube. Once the glass article 103 is separated from the glass tube 102 at the separation station 206, the glass article 103 is transferred to the secondary processing station 112 of the secondary turret 114. The secondary processing station 112 may include one or more forming stations 204 to form a second end of the glass article 103, which is opposite to the first end of the glass article 103. For example, the forming station 204 of the secondary processing station 112 may form one or more features at the bottom (second end) of the glass article 103, which is a vial.

[0083] The secondary processing stations of the secondary loop may include one or more heating stations 202, forming stations 204, polishing stations 208, cooling stations 210, unloading stations 216 or other stations, or combinations of secondary processing stations 112. In one or more embodiments, the secondary processing stations 112 of the secondary loop 118 can be used to form one or more features of the glass product 103 (for example, a vial, an ampoule, a barrel, or a syringe) at the end of the glass product 103 opposite to the end formed by the main turret 108. For example, in some embodiments, the glass product 103 is a vial, and the forming station 204 of the secondary loop 118 can form the bottom of the vial. Other features are also within the scope of concept, such as those unique to ampoules, barrels, syringes, etc. The secondary loop 118 may include one or more polishing stations 208 to finish the surface of the glass product. The secondary loop 118 may further include a plurality of cooling stations 210 and an unloading station 216, at which the finished glass product can be unloaded from the converter 100.

[0084] The foregoing description of the processing stations 106 of the primary loop 116 and the secondary processing stations 112 of the secondary loop 118 may represent a general converter 100 for producing vials from glass tubes 102. However, it should be understood that more or fewer processing stations 106 and secondary processing stations 112 may be utilized to produce vials or other glass articles (e.g., barrels, syringes, ampoules, or other glass articles) having different shapes. Furthermore, it should be understood that the processing stations 106 and secondary processing stations 112 may be arranged in any of a number of different orders and / or configurations to produce glass articles of different shapes.

[0085] Now refer to Figure 3A , schematically depicting the heating stations 202 of the converter 100. Each heating station 202 may include one or more heating elements 301. Examples of heating elements 301 may include, but are not limited to, fuel burners, lasers (e.g., carbon dioxide lasers), induction heaters, other heating devices, or combinations of these items. In some embodiments, a laser may be used to heat the glass tube 102. Figure 3A As shown in FIG. 1 , in some embodiments, the heating element 301 may include one or more burners 302, which are used to heat the forming station 204 ( Figure 2 ) or at the separation station 206 ( Figure 2 ) before the separation operation is performed at ). Figure 3A A single burner 302 is depicted, but it should be understood that more than one burner 302 may be employed in a single heating station 202. Each burner 302 may be fluidly coupled to a fuel supply 304, an oxygen supply 306, and (optionally) an air supply 308. Examples of fuels for the burners may include, but are not limited to, hydrogen, hydrocarbon fuel gases (such as, for example, methane, propane, and butane), other fuels, or combinations of these items. Each burner 302 may include a fuel control valve 310 to control the mass flow rate of the fuel gas delivered to the burner 302. Each burner 302 may also include an oxygen control valve 312 to control the mass flow rate of oxygen delivered to the burner 302. Each burner 302 may further include an air control valve 314 to optionally control the mass flow rate of air delivered to the burner 302. The burners 302 combust the fuel gas in the presence of oxygen and / or air to produce a flame that heats at least a target area of ​​the glass tube 102.

[0086] The heat of the flame produced by the burner 302 can be increased or decreased by changing the mass flow rate of the fuel gas, oxygen, and air fed to the burner 302 and by changing the ratio of the fuel gas to oxygen fed to the burner 302 and / or the ratio of the fuel gas to air fed to the burner 302. One or more of the fuel control valve 310, the oxygen control valve 312, or the air control valve 314 can be adjusted to adjust the ratio of fuel to oxygen and / or air. The burner 302 can be continuously fired, and the glass tubes 102 can be aimed into or out of contact with the flame produced by the burner 302 by rotating the main turret 108 and / or the secondary turret 114 to aim the glass tubes 102 into and out of the heating station 202. While positioned at the heating station 202, each glass tube 102 can be rotated about the holder axis D relative to the burner 302 by the holder 130 so that the glass tube 102 can be positioned at the downstream forming station 204 ( Figure 2 ) is evenly heated all around the specific area formed in the process.

[0087] Now refer to Figure 3B, schematically depicting a separation station 206 of the converter 100. The separation station 206 is positioned after one or more heating stations 202 in the direction 222 of the aiming movement of the main turret 108. The heating station 202 positioned before the separation station 206 heats the glass tube 102 to make the glass plastically deformable. The separation station 206 may include a separation tool 320. While the glass tube 102 (which has been made plastically deformable by the previous heating station 202) is rotated about the holder axis D by the holder 130, the separation tool 320 may engage with the outer surface 140 of the glass tube 102 to cut the glass tube 102 into a target length, thereby separating the product 103 ( Figure 1 Alternatively, in certain embodiments, the separation station 206 may include a burner (e.g., a hydrogen / oxygen burner) and / or a laser (e.g., a carbon dioxide laser) to cut the glass tube 102 into a target length and separate the product 103 from the glass tube 102. In other embodiments, the separation station 206 may include a separation tool 320 and at least one of a hydrogen / oxygen burner or a laser. Once separated from the glass tube 102, the product 103 may be transferred to the secondary turret 114 ( Figure 1 ) or removed from the converter 100.

[0088] Now refer to Figure 3C and 3D , schematically depicts an example of a forming station 204 of a converter 100. Each forming station 204 may include one or more forming tools 324 rotatably coupled to the forming station 204. The forming tool 324 may be rotatably coupled to the base 104 ( Figure 1 ) rotates around the tool processing axis E, which is connected to the main turret 108 ( Figure 1 )’s central axis A( Figure 1 ) is substantially parallel. While aiming to move into the forming station 204, the holder 130 rotates the glass tube 102 (which has been heated in the previous heating station 202). The rotatable forming tool 324 engages with the outer surface 140 of the glass tube 102. The forming tool 324 can be actuated into engagement with the outer surface 140 of the glass tube 102 by one or more actuators 326. The forming tool 324 is maintained in contact with the glass tube 102 for a certain contact time under a tool pressure maintained by the actuator 326. The forming tool 324 contacts the outer surface 140 of the heated glass tube 102, forming the glass tube 102 into a desired shape. After the contact time expires, the actuator 326 removes the engagement of the forming tool 324 with the glass tube 102. In one or more embodiments, the contact time may be different from the dwell time of the converter 100.

[0089] Figure 3CAn embodiment of a forming station 204 for forming a shoulder 142 of a vial formed from a glass tube 102 is schematically depicted. Figure 3D An exemplary embodiment of a forming station 204' for forming a flange 144 of a glass vial formed from a glass tube 102 is schematically depicted. The forming station 204' for forming the flange 144 includes three forming tools 324a, 324b, and 324c. Both forming tools 324a and 324b contact the outer surface 140 of the glass tube 102 to form the outer contour of the flange 144. A third forming tool 324c contacts the inner surface of the flange 144 of the glass tube 102 in a radially inward direction to form the inner diameter of the glass tube 102 at the flange 144. The third forming tool 324c also contacts the axial end of the glass tube 102 to form the axial surface of the flange 144. In some embodiments, the third forming tool 324c can be stationary, and the glass tube 102 is rotated around the third forming tool 324c by the holder 130. In some embodiments, a thin layer of lubricant (e.g., such as oil) can be disposed between the glass tube 102 and the third forming tool 324c to separate the glass tube 102 from contact with the third forming tool 324c. Although described with respect to forming vial structures, the forming station 204 can be configured to form other structures, such as, for example, a shoulder, neck, or tapered tip of an ampoule, or any other structure associated with an article other than a glass vial.

[0090] Figure 3E The cooling station 210 is schematically depicted with one or more cooling nozzles 340 positioned to direct a cooling fluid 342 (such as, for example, cold air or an inert gas) toward the glass tube 102. One or more of the cooling nozzles 340 may be positioned to direct the cooling fluid 342 toward a particular area of ​​the glass tube 102. One or more cooling fluid control valves 344 may be fluidly coupled to the cooling nozzles 340 to control the mass flow rate of the cooling fluid 342 delivered to the cooling nozzles 340, which allows for control of the cooling rate of the glass tube 102 as well as the temperature of the glass tube 102 and the temperature gradient in the glass tube 102.

[0091] Figures 3A-3E Included are schematic illustrations of several different examples of processing stations 106 that may be used in converter 100. However, it should be understood that other processing stations 106 having different structures, combinations of structures, or functions may be utilized to achieve the desired behavior of converting glass tube 102 into one or more glass articles.

[0092] Refer again Figure 2In operation, the main turret 108 aims and moves the glass tube 102 into the processing station 106, where the glass tube is fixed in the holder 130. At each processing station 106, a specific operation (e.g., heating, forming, perforating, separating, cooling, delivering, feeding, etc.) is performed on the glass tube 102. The dwell time is the time that the glass tube 102 spends in a particular processing station 106 before being aimed and moved by the main turret 108 to the next subsequent processing station 106. The converter 100 can be tuned so that all processing stations 106 complete their operations within the dwell time. At the end of the dwell time, the main turret 108 aims and moves the glass tube 102 to the next processing station 106. The aiming and moving time refers to the time it takes for the main turret 108 to aim and move the glass tube 102 from one processing station 106 to the next processing station 106, and is measured in time units. As used in the present disclosure, the total time per part per station is the sum of the dwell time and the aiming and moving time. The part rate (production rate) is the number of parts produced per unit time and is the inverse of the total time per part per station. In an embodiment, the aiming movement time of the main turret 108 may be up to 25% of the total time per part per station.

[0093] Examples of converters 100 for converting glass tubes 102 into glass vials include the RP16 model vial forming machine with an automatic tube feeder manufactured by AMBEG Dr. J. Dichter GmbH, which includes sixteen processing stations 106 in a main loop 116 and eight secondary processing stations 112. Other examples include the RP32 model vial forming machine manufactured by AMBEG Dr. J. Dichter GmbH, which has thirty-two processing stations 106 in a main loop 116 and two secondary loops 118 with eight secondary processing stations 112 in each secondary loop 118, and the Zeta 098 vial forming machine manufactured by Euromatic SRL, which has 36 processing stations 106. Another example may include the Zeta 103 barrel forming machine manufactured by Euromatic SRL, which is a converter for converting glass tubes 102 into barrels. The cartridge converter has similar characteristics to the previously described vial converter 100, but is used to produce glass articles having the form factor of a cartridge rather than a vial.

[0094] Although described in the context of a converter 100 for producing glass vials from glass tubes 102, it should be understood that the converter 100 can be configured to produce one or more other products, such as barrels, syringes, ampoules, or other glass products, by changing the order or configuration of the forming tools 324 and / or the processing stations 106 in the primary loop 116 or the secondary processing stations 112 in one or more secondary loops 118.

[0095] A typical converter 100 for producing articles from a glass tube 102 may be operated at production rates of from 30 parts per minute to 50 parts per minute. At these production rates, the thermal gradients within the glass tube 102 are extremely high and dynamic. Typically, a short length of glass tube 102 is heated from 200° C. to 1500° C. in a period of from 2 seconds to 4 seconds. Specifically, the heated length of glass tube 102 may experience a temperature gradient of up to 100° C. / minute or up to 200° C. / minute along a certain length of the tube. Reference Figure 4 For the glass tube 102, the length L is Figure 4 These large temperature gradients along the length L of the glass tube 102 help facilitate accurate dimensional control of heat separation within the converter 100 and accurate control of the thickness of the bottom of the glass article, for example, and control over the contour of the glass article.

[0096] The rapid heating of the glass tube 102 in the one or more processing stations 106 may also induce maximum temperature gradients through the thickness T of the heated glass tube 102. These temperature gradients may be, for example, and are not limited to, from 200° C. / minute to 300° C. / minute. Similar or higher temperature gradients may be induced during the forming process in the forming station 204 to form the shoulder 142 and flange 144 of the vial. These high thermal gradients induced along the length L of the glass tube 102 and through the thickness T of the glass tube 102 during conversion are important to understanding the dynamics of the conversion process, but are only somewhat understood within the capabilities of currently commercially available converters 100.

[0097] Now refer to Figure 5-6 , embodiments of the converter 100 described herein may utilize a thermal imaging system 120 to provide and / or enhance automated control of the converter 100 and the conversion process. The thermal imaging system 120 may be employed to measure one or more surface temperatures of the glass tube 102 during the conversion process. The thermal imaging system 120 includes a thermal imager 122 and a mounting device 126 for mounting the thermal imager 122 to the main turret 108. In some embodiments, the thermal imaging system 120 may also include one or more reflectors 124 coupled to the thermal imager 122 via the mounting device 126. The reflectors 124 may allow the thermal imager 122 to be oriented approximately vertically to reduce the spatial footprint of the converter 100. The thermal imaging system 120 is mounted to the main turret 108 such that the thermal imaging system 120 rotates with the main turret 108 and advances with the glass tube 102 through each processing station 106 ( Figure 1). The thermal imaging system 120 can be used to form a temperature profile of the glass tube 102 at any portion of the entire conversion process from glass tube to finished glass article by traveling with the glass tube 102 through each of the successive processing stations 106. The temperature profile can be used to identify, study, and control temperature gradients from one processing station 106 to the next.

[0098] In some embodiments, the thermal imager 122 may be a two-dimensional infrared thermal imaging camera that can capture light having wavelengths in the infrared spectrum. Specifically, in some embodiments, the thermal imager 122 can receive long-wave infrared light having a wavelength from 4 microns to 14 microns, from 4 microns to 10 microns, from 4 microns to 8 microns, from 4 microns to 7 microns, from 5 microns to 14 microns, from 5 microns to 10 microns, from 5 microns to 8 microns, from 5 microns to 7 microns, from 7 microns to 14 microns, from 7 microns to 10 microns, or from 7 microns to 8 microns. Infrared light includes a wide spectrum of wavelengths from 700 nanometers (nm) to 1 millimeter. However, longer wavelength infrared light generally indicates infrared light emitted by the outer surface 140 of the glass tube 102, which is the surface that is directly heated. Shorter wavelength infrared light from 700 nanometers to about 4 microns can be at least partially transmitted through the glass component of the glass tube 102. Therefore, the shorter wavelength infrared light received by the thermal imager 122 may have been emitted by an inner portion of the glass tube 102 or by an external structure positioned behind the glass tube 102 relative to the position of the thermal imager 122. The shorter wavelength infrared light of less than about 4 microns is therefore not indicative of the surface of the glass tube 102. At long wavelength infrared light (e.g., infrared light having a wavelength greater than about 14 microns), at least a portion of the infrared light having a long wavelength emitted from the surface of the glass tube 102 may be reflected away from the thermal imaging system. The glass component of the glass tube 102 converted by the converter 100 exhibits low transmittance and low reflectance to infrared light having a wavelength from 4 microns to 14 microns, and therefore exhibits greater infrared light emissivity in this wavelength range. For example, the glass tube 102 exhibits 0% transmittance and only 3% reflectance to infrared light having a wavelength of about 5 microns. Therefore, the emissivity of infrared light having a wavelength of about 5 microns from the glass tube 102 is about 97%. In another example, the reflectivity of infrared light having a wavelength of about 7.5 microns from the glass tube 102 is about 10% and the emissivity is 90%. Capturing infrared light having a wavelength in the range of about 4 microns to about 14 microns (e.g., from 4 microns to 7.5 microns or about 5 microns) can reduce errors in surface temperature measurements by avoiding integrating the temperature gradient through the thickness of the glass tube 102. The transmittance of infrared light through the glass tube 102 and the reflectivity of infrared light from the glass tube 102 introduce errors in the thermal image data captured by the thermal imager 122. A thermal imager 122 capable of capturing infrared light having a wavelength from 4 microns to 14 microns can exhibit enhanced temperature accuracy of thermal images obtained with the thermal imager 122. In one or more embodiments, the thermal imager 122 can have an object temperature range from 100° C. to 2000° C. or from 300° C. to 2000° C.

[0099] The thermal imager 122 may have an image capture rate of at least 30 Hz. In certain embodiments, the thermal imager 122 may have an image capture rate of from 30 Hz to 60 Hz or from 30 Hz to 50 Hz. In addition, the thermal imager 122 may conform to one or more interface protocols (such as, for example, the GigE Vision protocol) to allow the thermal imager to communicate with and transmit high-speed imaging data over an Ethernet connection to a computer having image analysis software (such as, for example, LabVIEW 1000 released by National Instruments). TM The thermal imager 122 may have an internal temperature sensor (not shown) integrated with a self-calibration system to allow the thermal imager 122 to measure the temperature of the infrared sensor assembly and adjust the image data to compensate for changes in the temperature of the thermal imager 122.

[0100] As previously described, the thermal imager 122 is mounted to the main turret 108 of the converter 100 using the mounting device 126. Figure 6 , the mounting device 126 can be attached to an outer portion 128 of the main turret 108 so that the mounting device 126 and the thermal imager 122 rotate with the main turret 108. In some embodiments, the main turret 108 of the converter 100 can be enclosed in a housing, such as a steel mesh housing 127. In these embodiments, the steel mesh housing 127 is the outer portion 128 of the main turret 108. The mounting device 126 can be mounted to a housing having a track support system 129 ( Figure 5) steel mesh housing 127. In certain embodiments, the mounting device 126 may allow for temporary removal of the thermal imager 122 and / or the reflector 124 from the main turret 108 of the converter 100. The mounting device 126 positions the thermal imager 122 and the reflector 124 at a fixed angular position on the main turret 108 so that the thermal imager 122 and the reflector 124 follow the entire cycle of a single holder 130 and glass tube 102 through the converter 100. The mounting device 126 may include an imager support 502 and a reflector support 504. The thermal imager 122 may be removably coupled to the imager support 502. The imager support 502 may be adjustable in one or more directions to orient the thermal imager 122 relative to the holder 130 and / or the glass tube 102. For example, the imager support 502 may include a vertical adjustment member (i.e., upward or downward parallel to the central axis A of the main turret 108), a radial adjustment member relative to the main turret 108 (i.e., used to move the thermal imager 122 closer to or farther away from the outer portion 128 of the main turret 108), an angle adjustment member (i.e., used to adjust the angular position of the thermal imager 122 relative to one of the holders 130), a rotation adjustment member (i.e., rotationally adjusting the camera to change the optical centerline OC formed by the camera and Figure 6 The angle between the XY planes of the axes in the image) or other adjustment components.

[0101] In some embodiments, the imager support 502 can be configured to position the thermal imager 122 to directly capture images of the glass tube 102 while the glass tube 102 is being processed. Figure 5 and Figure 6 108. The optical centerline OC of the thermal imager 122 is aligned on the XY plane of the coordinate axis of the primary loop 116. However, in a typical converter 100, the space around the processing station 106 of the primary loop 116 and / or the secondary processing station 112 of the secondary loop 118 is limited, and the act of positioning the thermal imager 122 so that the optical centerline OC of the thermal imager 122 is on the XY plane and radially aligned with the glass tube 102 causes the thermal imager 122 to extend radially outward relative to the main turret 108. This may cause the thermal imager 122 and / or the mounting device 126 to contact components of the converter 100 or interfere with the operation of the converter 100 when the thermal imager 122 rotates with the rotation of the main turret 108. In addition, in this configuration, the thermal imager 122 may extend radially outward relative to the rotating main turret 108, which may create a dangerous condition during operation.

[0102] To avoid these space issues, in some embodiments, the imager support 502 may be adjustable to orient the thermal imager 122 so that the optical centerline OC of the thermal imager 122 is relative to the Figure 5 and Figure 6In one or more embodiments, the thermal imager 122 may be positioned such that the optical centerline OC of the thermal imager 122 is parallel to the central axis A of the main turret 108 (i.e., parallel to the central axis A of the main turret 108). Figure 5 and Figure 6 Alternatively, thermal imager 122 may be positioned such that optical centerline OC forms a non-zero angle of less than 90° relative to the axial plane of main turret 108. Mounting thermal imager 122 at a non-zero angle relative to the axial plane of main turret 108 may help avoid interfering with the operation of converter 100 and / or creating a hazardous condition.

[0103] The reflector support 504 can be coupled to the imager support 502 and can position the reflector 124 to reflect infrared light from the glass tube 102 toward the lens 506 of the thermal imager 122. In some embodiments, the reflector support 504 can position the reflector 124 to align with the optical centerline OC of the thermal imager 122. In one or more embodiments, the reflector support 504 can allow the reflector 124 to be vertical (i.e., along the direction of the thermal imager 122) relative to the thermal imager 122. Figure 5 and Figure 6 One or more of +Z / -Z axis) adjustment, radial adjustment, angular adjustment, rotational adjustment or other directional adjustment of the coordinate axis.

[0104] Reference Figure 5, the reflector 124 may be coupled to the mounting device 126 and positioned within the field of view of the thermal imager 122 such that the reflector 124 reflects infrared light toward the lens 506 of the thermal imager 122. In one or more embodiments, the reflector 124 may be positioned such that the optical centerline OC of the thermal imager 122 intersects the reflective surface 508 of the reflector. Alternatively, the reflector 124 may be positioned within the field of view of the thermal imager 122 such that the reflective surface 508 reflects infrared light toward the lens 506, but the optical centerline OC of the thermal imager 122 does not intersect the reflective surface 508 of the reflector 124. The reflector 124 may be tilted relative to the optical centerline OC of the thermal imager 122 to reflect infrared light emitted from the outer surface 140 of the glass tube 102 at a particular holder position 136 toward the thermal imager 122. 7 , in general, the reflector 124 is tilted so that the reflective surface 508 of the reflector 124 forms a non-zero angle α of less than 90° with the optical centerline OC of the thermal imager 122. In other words, the reflective surface 508 of the reflector 124 may be tilted so that the reflective surface 508 is not perpendicular to the optical centerline OC of the thermal imager 122. In one or more embodiments, the reflector 124 may be positioned to reflect infrared light from a holder position 136 toward the thermal imager 122, the holder position being positioned directly radially inward of the thermal imager 122 relative to the central axis A of the main turret 108. Alternatively, in other embodiments, the reflector 124 may be positioned to reflect infrared light from a holder position 136 that is one or more positions clockwise or counterclockwise relative to the position of the thermal imager 122 (i.e., one or more positions forward / upstream or aft / downstream of the position where the thermal imager 122 is attached to the main turret 108). While specific orientations of the reflector 124 and thermal imager 122 have been described herein, it should be understood that the reflector 124 and thermal imager 122 may be positioned and oriented in any of a number of configurations depending on the configuration of the particular transducer 100 .

[0105] In some embodiments, the reflective surface 508 of the reflector 124 can be highly reflective to infrared light. In one or more embodiments, the reflective surface 508 of the reflector 124 can have an average reflectivity of 96% or more, 97% or more, 98% or more, or 99% or more for infrared light having a wavelength from 4 micrometers (μm) to 14 μm. In one or more embodiments, the reflective surface 508 of the reflector 124 can have an average reflectivity of 96% or more for light having a wavelength from 4 μm to 14 μm. Fig.17, the reflector 124 may include a reflector base 510 and a reflective coating 512 applied to the reflector base 510 to produce the reflective surface 508. The reflector base 510 may be thermally stabilized to avoid distorting the image. In some embodiments, the reflector base 510 may be quartz, such as fused quartz, for example. In some embodiments, the reflective coating 512 may be, for example, a gold coating.

[0106] Reference Fig. 7A As previously described, in certain embodiments, the thermal imager 122 may be positioned to directly receive infrared light emitted from the outer surface 140 of the glass tube 102 at a particular holder position 135 of the main turret 108. Specifically, the thermal imager 122 may be positioned so that the infrared light emitted from the outer surface 140 of the glass tube 102 travels directly along the path 710 to the lens 506 of the thermal imager 122 without being reflected by a reflector (e.g., the reflector 124). The thermal imager 122 receives the infrared light emitted by the outer surface 140 of the glass tube 102 and captures a thermal image representing the wavelength and intensity of the infrared light received by the thermal imager 122. The thermal imager 122 travels with the main turret 108 so that the thermal imaging system 120 is positioned to view the glass tube 102 as it moves through the successive processing stations 106 ( Figure 1 ) at each processing station in the conversion process. Capturing thermal imaging data from infrared light emitted by the outer surface 140 of the glass tube 102 allows for mapping the distribution of the temperature of the outer surface 140 of the glass tube 102 as a function of time throughout the conversion process.

[0107] Reference Figure 7B In some embodiments, the thermal imager 122 may be positioned to directly receive infrared light emitted by the outer surface 140 of the glass tube 102. In addition, one or more stationary reflectors 700 may be coupled to the base 104 of the converter 100 at the processing station 106 to reflect infrared light emitted by the inner surface 146 of the glass tube 102 toward the thermal imager 122. In some embodiments, each stationary reflector 700 may be vertically positioned lower than the processing station 106 (i.e., at a position relative to the processing station 106). Figure 7B Positioning the stationary reflector 700 vertically lower than the processing station 106 allows the stationary reflector 700 to reflect the inner surface 146 ( Figure 4). Reflecting the infrared light emitted from the inner surface 146 of the glass tube 102 toward the thermal imager 122 may allow the thermal imaging system 120 to map or determine the temperature of the inner surface 146 of the glass tube 102. The infrared light emitted from the inner surface 146 of the glass tube 102 may travel along a path 712 that starts from the inner surface 146 of the glass tube 102 in a generally downward direction (i.e., in a Figure 7B 106) and reflects off the stationary reflector 700 toward the lens 506 of the thermal imager 122. Because the thermal imager 122 is coupled to the main turret 108 and rotates with the main turret 108, the thermal imager 122 only moves into position to receive infrared light emitted by the inner surface 146 of the glass tube 102 and reflected from a particular stationary reflector 700 once each time the main turret 108 cycles through the main loop 116 of the processing stations 106. In some embodiments, the stationary reflector 700 may be positioned at multiple processing stations 106 so that the thermal imager 122 can capture thermal image data of the inner surface 146 of the glass tube 102 from multiple processing stations 106 during each cycle of the main turret 108.

[0108] Reference Figure 7C As previously described, the thermal imager 122 may be positioned such that the lens 506 of the thermal imager 122 is not oriented to directly receive infrared light from the outer surface 140 of the glass tube 102. Figure 7C is shown as being oriented generally vertically (i.e., in Figure 7C In some embodiments, the thermal imager 122 may be oriented such that the optical centerline OC of the thermal imager 122 is aligned with the centerline C of the glass tube 102. L As previously described, the mounting device 126 can allow the glass tube 102 to be substantially parallel to the centerline C L The thermal imager 122 is rotated, tilted, or angled. The reflector 124 is coupled to the mounting device 126 so that the reflector 124 moves with the thermal imager 122 as the main turret 108 is aimed and moved through the processing stations 106. The reflector 124 can be positioned to reflect infrared light from the outer surface 140 of the glass tube 102 toward the lens 506 of the thermal imager 122. In this configuration, both the reflector 124 and the thermal imager 122 move with the main turret 108 so that the thermal imaging system 120 moves with the glass tube 102 as it rotates to successive processing stations 106 ( Figure 1) and captures thermal image data of the outer surface 140 of the glass tube 102 at a particular holder position 136 while rotating between the processing stations. Specifically, the reflector 124 can be positioned to reflect infrared light emitted radially outward from the outer surface 140 of the glass tube 102 toward the thermal imager 122, which receives the infrared light reflected from the reflector 124 and captures a thermal image representing the wavelength and intensity of the infrared light received by the thermal imager 122. The infrared light travels outward from the outer surface 140 of the glass tube 102 along the path 714 and reflects off the reflector 124 toward the lens 506 of the thermal imager 122.

[0109] 7D , the reflector 124 may be positioned to reflect infrared light emitted by the outer surface 140 of the glass tube 102 and infrared light emitted by the inner surface 146 of the glass tube 102 toward the lens 506 of the thermal imager 122. The infrared light emitted from the outer surface 140 of the glass tube 102 travels outwardly from the outer surface 140 of the glass tube 102 along a path 714 and reflects off the reflector 124 toward the lens 506 of the thermal imager 122. The infrared light emitted from the inner surface 146 travels from the inner surface 146 of the glass tube 102 along a path 716 toward the reflector 124 and is reflected by the reflector 124 toward the lens 506 of the thermal imager 122. Because the reflector 124 travels with the thermal imager 122 as it is aimed through the plurality of processing stations 106, the reflector 124 may allow the thermal imager 122 to capture thermal image data from the outer surface 140 and the inner surface 146 of the glass tube 102 at each of the processing stations 106. In some embodiments, the thermal imager 122 may capture thermal image data from the outer surface 140 and the inner surface 146 of the glass tube 102 simultaneously (e.g., such as in a single thermal image).

[0110] Reference Fig. 7E In some embodiments, the thermal imaging system 120 may include a supplemental reflector 125 that may be coupled to the mounting device 126 such that the supplemental reflector 125 travels with the thermal imager 122 and the reflector 124. In these embodiments, infrared light emitted from the outer surface 140 of the glass tube 102 travels from the outer surface 140 of the glass tube 102 along a path 714 toward the reflector 124 and is reflected by the reflector 124 toward the lens 506 of the thermal imager 122. Infrared light emitted from the inner surface 146 of the glass tube 102 travels from the inner surface 146 of the glass tube 102 along a path 718 toward the supplemental reflector 125 and is reflected by the supplemental reflector 125 toward the lens 506 of the thermal imager 122. In some embodiments, the supplemental reflector 125 may be positioned vertically lower than the reflector 124 (i.e., at a position 714 below the reflector 124). Fig. 7EBecause both the reflector 124 and the supplemental reflector 125 travel with the thermal imager 122 as the thermal imager 122 is aimed and moved through the plurality of processing stations 106, the reflector 124 and the supplemental reflector 125 can allow the thermal imager 122 to capture thermal image data from the outer surface 140 and the inner surface 146 of the glass tube 102 at each of the processing stations 106. In some embodiments, the thermal imager 122 can capture thermal image data from the outer surface 140 and the inner surface 146 of the glass tube 102 simultaneously.

[0111] Reference Figure 7F In some embodiments, one or more stationary reflectors 700 may be coupled to the base 104 of the converter 100 at the processing station 106. In some embodiments, each stationary reflector 700 may be positioned vertically below the processing station 106. The stationary reflectors 700 may be tilted to reflect infrared light emitted by the inner surface 146 of the glass tube 102 toward the thermal imager 122 as the thermal imager 122 is aimed and moved into position in the processing station 106. The infrared light emitted from the inner surface 146 of the glass tube 102 may be directed generally downward (i.e., at a predetermined position) along a path 720. Figure 7F 106) to the stationary reflector 700 and is reflected by the stationary reflector 700 toward the lens 506 of the thermal imager. Because the thermal imager 122 is coupled to the main turret 108 and rotates with the main turret 108 as the main turret 108 aims and moves each holder 130 through the plurality of processing stations 106, the thermal imager 122 is positioned to receive the reflected infrared light from the stationary reflector 700 once each time the main turret 108 cycles through the main loop 116 of the processing stations 106. The infrared light reflected by the stationary reflector 700 to the thermal imager 122 may be captured only once per cycle of the main turret 108 by the thermal imager 122. Positioning the stationary reflector 700 below the processing stations 106 allows the stationary reflector 700 to reflect the infrared light reflected by one or more inner surfaces 146 ( Figure 4 ) emitted by the glass tube 102, which may allow the thermal imaging system 120 to map the distribution of or determine the temperature of one or more inner surfaces 146 of the glass tube 102.

[0112] Reference Figure 7G, in some embodiments, the stationary reflector 700 can be oriented to reflect infrared light from the inner surface 146 of the glass tube 102 toward the reflector 124 coupled to the mounting device 126. In these embodiments, infrared light from the inner surface 146 of the glass tube 102 travels along a path 722 from the inner surface 146 of the glass tube 102 to the stationary reflector 700, reflects off the stationary reflector 700 toward the reflector 124, and then reflects off the reflector 124 toward the lens 506 of the thermal imager 122. At the same time, infrared light emitted from the outer surface 140 of the glass tube 102 travels from the outer surface 140 of the glass tube 102 toward the reflector 124 along a path 714, and reflects from the reflector 124 toward the lens 506 of the thermal imager 122. Other stationary mirrors 700 may be coupled to the base 104 beneath other processing stations 106, and other supplemental mirrors 124 may be coupled to the main turret 108 or mounting device 126 to achieve different configurations or different viewing angles of the glass tube 102 during one or more stages of the conversion process.

[0113] In certain embodiments, the thermal imaging system 120 may include a plurality of thermal imagers 122. The plurality of thermal imagers 122 may be coupled to the primary turret 108, the secondary turret 114, or both so as to rotate with the primary turret 108 or the secondary turret 114. In certain embodiments, each thermal imager in the plurality of thermal imagers 122 may be positioned to capture thermal imaging data from a separate holder location 136. In some embodiments, the thermal imaging system 120 may include one or more thermal imagers 122 coupled to the base 104 of the converter 100 or other stationary structure in a stationary position (e.g., the ground, a wall, or other structure adjacent to the converter 100) to capture thermal imaging data from a particular processing station 106 and / or secondary processing station 112 as the glass tube 102 is aimed and moved through the particular processing station 106 and / or secondary processing station 112.

[0114] Now refer to Fig. 8A , coupling the thermal imaging system 120 to the main turret 108 such that the thermal imaging system 120 travels in a continuous loop centered about the central axis A of the main turret 108, which creates unique challenges for delivering power and cooling fluid to the thermal imaging system 120 and receiving data from the thermal imaging system 120. Therefore, in some embodiments, the thermal imaging system 120 may include one or more rotating electrical and / or gas joints, which may allow for power, data exchange, and cooling of the thermal imaging system. In one or more embodiments, the thermal imaging system may include a slip ring 802 (sometimes referred to as a rotary electrical joint) that may provide a rotary connection to allow power and data transmission to and from the thermal imaging system 120. The slip ring 802 may operatively couple the thermal imager 122 to the processor 900 ( Fig. 9). The slip ring 802 may be a double ring structure having an inner ring 804 and an outer ring 806. Either the inner ring 804 or the outer ring 806 is stationary, while the other of the inner ring 804 or the outer ring 806 rotates relative to the stationary ring. The slip ring 802 may have a rotation axis that is parallel and aligned with the central axis A of the main turret 108. Aligning the axis of the slip ring 802 with the central axis A of the main turret 108 may prevent the cable 808 and the data cable 810 extending from the slip ring 802 to the thermal imaging system 120 from being entangled after the rotation of the main turret 108.

[0115] The slip ring 802 may include a plurality of loops (not shown) formed between the inner ring 804 and the outer ring 806. Power (e.g., 24 volts of power, for example) and data may be electronically transmitted radially between the inner radial surface of the outer ring 806 and the outer radial surface of the inner ring 804 while the inner ring 804 and the outer ring 806 rotate relative to each other. The outer ring 806 may be electrically coupled to a power source and / or may also be communicatively coupled to the processor 900 ( Fig. 9 ). The inner ring 804 can be electrically coupled to the thermal imager 122 to deliver power to the thermal imager 122, and can be communicatively coupled to the thermal imager 122 to send and receive data from the thermal imager 122. Power can be transmitted from the slip ring 802 to the thermal imager 122 via one or more electrical cables 808. In addition, data can be transmitted between the slip ring 802 and the thermal imager 122 via one or more data cables 810 (such as, for example, Ethernet cables). The slip ring 802 can communicatively couple the thermal imager 122 to the processor 900 ( Fig. 9 ), the processor may be remotely (ie, spaced apart) positioned in a stationary position relative to the thermal imager 122 to facilitate the transmission of data to and from the thermal imager 122. The processor 900 ( Fig. 9 ) may be temperature sensitive, and the ability to remotely locate processor 900 and efficiently transmit data to processor 900 can avoid the need to add special heat-resistant structures or cooling systems to further protect processor 900.

[0116] In one or more embodiments, the rotating portion of the slip ring 802 (e.g., Fig. 8A The inner ring 804 in FIG. 1 may be supported by a support 812 (e.g., such as an electrical conduit or a bracket) that is coupled to the main turret 108 so as to rotate with the main turret 108. The stationary portion of the slip ring 802 (e.g., such as Fig. 8A808. The outer ring 806 in the main turret 108 (shown in FIG. 1 ) may be coupled to a stationary support 814 that is attached to a fixed, non-rotating surface (not shown) that is separate from the main turret 108. The stationary support 814 may be, for example, an electrical conduit, a bracket, or other support structure. In addition, in one or more embodiments, the inner ring 804 of the slip ring 802 may have a center hole 816 that provides an inlet and outlet through the center hole for one or more fluid conduits 818. The center hole 816 may be centered on the rotation axis of the slip ring 802 that is aligned with the center axis A of the main turret 108. The fluid conduit 818 may pass through the center hole 816 of the inner ring 804 to deliver cooling fluid or other fluids to the thermal imaging system 120 or other parts of the main turret 108. In some embodiments, the slip ring 802 may be free to rotate relative to the fluid conduit 818 (i.e., the slip ring 802 is not coupled to the fluid conduit 818).

[0117] Reference Figure 8B In an alternative embodiment, the thermal imaging system 120 may include a power source 840 (e.g., a battery, for example) that is removably coupled to the main turret 108 so as to rotate with the main turret. The power source 840 may be electrically coupled to the thermal imager 122 to provide power to the thermal imager 122. The power source 840 may be removable from the main turret 108 so that the power source 840 can be replaced and / or recharged. In one or more embodiments, the thermal imager 122 may be communicatively coupled to the processor 900 via one or more wireless communication devices 842 using one or more wireless communication protocols. The wireless communication device 842 may be coupled to the main turret 108 so as to rotate with the main turret. The wireless communication device 842 may be communicatively coupled to the thermal imager 122. In some embodiments, the one or more wireless communication devices and / or protocols may be used to transmit thermal imaging data between the thermal imager 122 and the processor 900.

[0118] Refer back Fig. 8AIn some embodiments, the thermal imaging system 122 may also include a cooling system 820 to cool the thermal imager 122. The cooling system 820 may include a cooling fluid source 822, a fluid rotating union 824 in fluid communication with the cooling fluid source 822, and a fluid conduit 818 in fluid communication with the fluid rotating union 824. The cooling fluid may be a compressed gas, such as, for example, filtered air, nitrogen, or other gas or gas combination. In some embodiments, the cooling fluid may be clean dry air (i.e., air from which moisture, particles, dirt, oil, or other contaminants have been removed) to avoid introducing contaminants into the thermal imaging system 120 that may adversely affect the performance of the thermal imaging system 120. Alternatively, the cooling fluid may be nitrogen. In some embodiments, the cooling system 820 may include at least one of a regulator, a moisture remover, a particle filter, a coalescing filter, or a combination of these items. The cooling fluid source 822 may include a compressed gas storage tank, a gas compressor, or other compressed gas system or a combination of cooling fluid sources.

[0119] The fluid rotary union 824 includes a stationary portion 826 that is fluidly coupled to the cooling fluid source 822 and a rotating portion 828 that is rotatably coupled to and rotatable relative to the stationary portion 826. The fluid rotary union 824 includes a union axis that is parallel to and aligned with the central axis A of the main turret 108 such that the rotating portion 828 of the fluid rotary union 824 can rotate in unison with the rotation of the main turret 108. The rotating portion 828 of the fluid rotary union 824 can be fluidly coupled to a fluid conduit 818 that extends from the fluid rotary union 824 to the thermal imager 122 to deliver cooling fluid to the thermal imager 122.

[0120] The cooling system 820 may further include one or more cooling fluid conduits 830 in fluid communication with the fluid conduit 818 and positioned to deliver cooling fluid to portions of the thermal imaging system 120. In one or more embodiments, one or more of the cooling fluid conduits 830 may be positioned to deliver cooling fluid to the thermal imager 122. In some embodiments, the thermal imager 122 may be maintained at a temperature of less than about 50° C. to maintain accurate operation of the infrared sensor suite within the thermal imager 122. A combustion gas cover (not shown) integrated with the converter 100 may be used to extract the combustion gases toward the central axis A of the main turret 108 and the combustion gases generated by the heating element 301 ( Figure 3A ) and draws away the excess heat generated by the converter 100. Therefore, the thermal imager 122 is generally not exposed to the heat from the heating element 301 ( Figure 3A) of the converter 100. However, the thermal imager 122 may be exposed to some heat from the conversion process, and additional heat may be inherently generated due to the operation of the sensor suite and electronics of the thermal imager 122. Cooling fluid directed toward the thermal imager 122 may be used to maintain the temperature of the thermal imager 122 at or below 50°C. In some embodiments, the cooling system 820 is coupled to the cooling station 210 ( Figure 3E ) independently. However, in one or more embodiments, cooling station 210 ( Figure 3E ) and cooling system 820 may share a common cooling fluid source 822.

[0121] In certain embodiments, the thermal imaging system 120 may include a cleaning system 832 to clean the lens 506 of the thermal imager 122, the reflective surface 805 of the reflector 124, or both. During operation of the converter 100 and the thermal imaging system 120, oil and combustion products may be deposited on the lens 506 of the thermal imager 122 and the reflective surface 508 of the reflector 124 (e.g., due to oil condensation on the reflector 124 or the lens 506), which may reduce the reflectivity of the reflector 124 and interfere with the passage of infrared light through the lens 506 of the thermal imager 122, thereby introducing errors and inaccuracies into the image data collected by the thermal imager 122. In some embodiments, the cleaning system 832 may include one or more nozzles 834 positioned to deliver fluid to the lens 506 of the thermal imager 122 to clean the lens 506 of the thermal imager 122 from oil, dirt, and other contaminants. The nozzles 834 may be fluidly coupled to a fluid delivery conduit 836 that delivers fluid from a fluid source (not shown) to the nozzles 834. In some embodiments, one or more of the nozzles 834 may be positioned to deliver fluid to the reflective surface 508 of the reflector 124 to clean oil, dirt, and other contaminants from the reflective surface 508. A fluid that is free of particles, dirt, oil, or other contaminants may be used to clean the lens 506 of the thermal imager 122, the reflective surface 508 of the reflector 124, or both to avoid further contamination of the lens 506 and the reflector 124. For example, the fluid may be nitrogen, clean air, other gases, or combinations thereof. In certain embodiments, the cleaning system 832 may be fluidly coupled to the cooling system 820 so that a cooling fluid is delivered to the nozzles 834 and used as a fluid for cleaning the lens 506, the reflector 124, or both of the thermal imager 122.

[0122] The thermal imaging system 120 described herein may be adapted for use with the secondary turret 114 of the converter 100. Fig.18A and 18B, the secondary turret 114 may include a thermal imaging system 120 coupled to the secondary turret 114 so as to rotate therewith. In certain embodiments, the thermal imaging system 120 may be coupled to the shaft 1806 of the secondary turret 114 such that the thermal imaging system 120 is positioned at the center of the secondary turret 114. As previously discussed, the thermal imaging system 120 includes a thermal imager 122 and a mounting device 126. The thermal imaging system 120 coupled to the secondary turret 114 may capture thermal imaging data from the inner surface 146 and / or the outer surface 140 of the glass tube 102 as the glass tube 102 is aimed at the secondary processing station 112 moving through the secondary loop 118 via the secondary turret 114. Referring to Fig.18A In some embodiments, the thermal imager 122 may be positioned at the center of the secondary turret 114 and may be positioned vertically (i.e., at Fig.18A The optical centerline OC of the thermal imager 122 is substantially parallel to the central axis B of the secondary turret 114. In this configuration, the reflector 124 can be positioned and oriented to reflect infrared light from the outer surface 140 and / or the inner surface 146 of the glass tube 102. Fig.18B In other embodiments, the thermal imager 122 may be oriented generally horizontally (i.e., Fig.18B 102), so that the thermal imager 122 directly receives infrared light from the outer surface 140 of the glass tube 102. In these embodiments, the thermal imager 122 can face generally radially outward relative to the centerline B of the secondary turret 114. In this orientation, infrared light emitted by the outer surface 140 of the glass tube 102 can travel radially inward from the glass tube 102 directly toward the thermal imager 122. Other configurations of the thermal imaging system 120 (including the use of supplemental reflectors 125 as described herein) Fig. 7E )、Stationary reflector 700( Figure 7B ) or a combination of reflectors 124, 125, 700 to reflect infrared light from the inner surface 146 or the outer surface 140 of the glass tube 102 toward the thermal imager 122 can be adapted to the secondary turret 114.

[0123] Refer back Fig. 9 , the thermal imaging system 120 may include a processor 900, one or more memory modules 902 communicatively coupled to the processor 900, and machine-readable instructions stored in the one or more memory modules 902. The processor 900 may be communicatively coupled to the thermal imager 122 via a communication path 904, which may include a data cable 810 ( FIG. 8 ) and / or one or more wireless communication devices 842 ( FIG. 10 ) utilizing a standard wireless communication protocol. Figure 8B). Suitable wireless communication protocols may include 802.11 family protocols, Bluetooth protocols, ZigBee IEEE 802 standard protocols, etc. The use of a data cable 810 passing through a slip ring 802 or other rotating electrical coupling to communicatively couple the processor 900 to the thermal imager 122 is shown in Fig. 8A The data cable 810 may be an electrical wire, a fiber optic data cable, or other data cable. The use of the wireless communication device 842 to communicatively couple the processor 900 to the thermal imager 122 is shown in FIG. Figure 8B middle.

[0124] The processor 900 may allow for automated analysis of image data collected by the thermal imager 122. By executing machine-readable instructions stored in the memory module 902, the processor 900 may cause the thermal imaging system 120 to receive image data captured by the thermal imager 122, process the image data, and determine at least one characteristic of the glass tube 102. The characteristics of the glass tube 102 determined from the thermal image data may include one or more surface temperatures, temperature gradients, dimensions of the glass tube 102 (i.e., dimensions of the physical boundaries of the glass tube), viscosities at various locations of the glass tube 102, temperature distribution of the glass tube as a function of time, the centerline of the glass tube, other characteristics, or combinations thereof. The machine-readable instructions, when executed by the processor 900, may also cause the thermal imaging system 120 to store the thermal image data and / or the characteristics of the glass tube 102 determined from the thermal image data, or to display the data and / or the characteristics of the glass tube 102 on one or more displays 906. In one or more embodiments, the machine-readable instructions stored in the memory module 902 may include one or more image analysis software packages. Examples of image analysis software packages include LabVIEW 1000, released by National Instruments. TM Other commercially available image analysis software (off-the-shelf or otherwise modified) may also be used with the thermal imaging system 120 .

[0125] The machine-readable instructions, when executed by the processor 900, may cause the thermal imaging system 120 to perform at least the following steps: using the thermal imager 122 to capture thermal imaging information of the glass tube 102; transmitting the thermal imaging information from the thermal imager 122 to the processor 900; receiving the thermal imaging information from the thermal imager 122 at the processor 900; processing the thermal imaging information; and determining one or more characteristics of the glass tube 102 from the thermal imaging information. In certain embodiments, when executed by the processor 900, the machine-readable instructions may cause the thermal imaging system 120 to further determine one or more physical boundaries of the glass tube 102 from the thermal imaging data. In certain embodiments, the machine-readable instructions, when executed by the processor 900, may cause the thermal imaging system 120 to perform one or more of the following steps: identifying a centerline of the glass tube 102 from the thermal image information; drawing the centerline on a thermal image captured by the thermal imager 122; converting infrared wavelength data to temperature data; compiling the temperature data to determine one or more temperature distributions and / or temperature gradients of the glass tube 102; and / or determining a temperature distribution of the glass tube 102 as a function of time (e.g., a graphical plot or a data table). In certain embodiments, the machine-readable instructions, when executed by the processor 900, may cause the thermal imaging system 120 to calculate the glass viscosity of the glass tube 102 at a specific location and the viscosity of the glass tube 102 as a function of the temperature model from the temperature of the glass tube 102. In certain embodiments, the thermal imaging system 120 may calculate a viscosity gradient through the thickness of the glass tube 102.

[0126] In certain embodiments, the machine-readable instructions, when executed by the processor 900, may cause the thermal imaging system 120 to calculate at least one metric from the processed thermal image information. The at least one metric may be retrieved by a control algorithm, which may calculate at least one process control variable (e.g., such as a controlled variable) or process control parameter (e.g., such as a gain constant or other process control parameter) from the at least one metric.

[0127] The act of indirectly capturing thermal images by using the reflector 124 to reflect infrared light toward the thermal imager 122 introduces errors from the reflector as compared to direct image capture without the reflector 124. When processing the thermal image information, the machine-readable instructions, when executed by the processor 900, may cause the thermal imaging system 120 to apply one or more correction factors to the thermal image information to correct for the errors introduced by the reflector 124. When one or more stationary reflectors 700 ( FIG. 7 ) are used with the thermal imaging system 120, the machine-readable instructions, when executed by the processor 900, may cause the thermal imaging system 120 to apply a plurality of correction factors to the thermal image information.

[0128] In one or more embodiments, the machine-readable instructions stored in the one or more memory modules 902 may cause the thermal imaging system 120 to perform at least the following steps when executed by the processor 900: determine a first characteristic or temperature of the glass tube 102 at the first processing station 106; determine a second characteristic or temperature of the glass tube 102 at the second processing station 106 located downstream of the first processing station 106; calculate a difference between the first characteristic or temperature and the second characteristic or temperature; and transmit an output representing the difference between the first characteristic or temperature and the second characteristic or temperature. In some embodiments, the first characteristic and the second characteristic are at the outer surface 140 ( Figure 4 ) or inner surface 146( Figure 4 ) is the estimated temperature at a specific physical point or area (e.g. Figure 4 140 at the shoulder 142 depicted in FIG. 14 ). Alternatively, in other embodiments, the first characteristic and the second characteristic may be an average temperature of the glass tube 102. For example, in certain embodiments, the first characteristic and the second characteristic may refer to an average centerline temperature of the glass tube 102. Additionally, the first and second characteristics may be average temperatures taken over a certain area of ​​the glass tube 102 or glass article 103. The first characteristic and the second characteristic may be an interior surface temperature or an exterior surface temperature of the glass tube 102 or glass article 103.

[0129] In one or more embodiments, the machine-readable instructions, when executed by the processor 900, may cause the thermal imaging system 120 to store thermal imaging data in one or more of the memory modules 902. In one or more embodiments, the machine-readable instructions may cause the thermal imaging system 120 to store and maintain a database of thermal imaging data and / or glass tube characteristics determined from the thermal imaging data, which may be used to develop baseline targets and / or metrics for converter 100 operating parameters to facilitate machine startup and / or as set points for one or more process control methods used to control the converter 100. In certain embodiments, the machine-readable instructions, when executed by the processor 900, may cause the thermal imaging system 120 to store data from a particular glass article in the one or more memory modules 902 and index the data from a particular glass article by part identification so that the thermal history of a particular part may be accessed for further analysis and investigation.

[0130] The regularity errors caused by the reflector 124 may be introduced into the image data captured by the thermal imager 122. In one or more embodiments, the machine-readable instructions, when executed by the processor 900, may cause the thermal imaging system 120 to apply one or more data filters to the thermal image data. In one or more embodiments, the machine-readable instructions, when executed by the processor 900, may cause the thermal imaging system 120 to receive thermal image data from the thermal imager 122 at a target sampling rate. The target sampling rate may be modified to affect the overall capture rate of the thermal imaging system 120.

[0131] Still refer to Fig. 9 , the thermal imaging system 120 may further include a display 906 communicatively coupled to the processor 900. The memory module 902 may include machine-readable instructions that, when executed by the processor 900, cause the thermal imaging system 120 to display one or more outputs (e.g., thermal images, graphs, and / or data tables including glass tube temperature data from the thermal images) on the display 906. The output may be one or more graphical outputs, such as Fig.10 A graph of the surface temperature of the glass tube 102 as a function of time at a particular location as shown in Figures 11A-11D The output to the display 906 may also include one or more data tables that provide numerical representations of the temperature data generated by the thermal imaging system 120 rather than graphical representations.

[0132] Refer to Figures 7 and Fig. 9 In operation, the thermal imager 122 is positioned to capture thermal image data from the glass tube 102, which is removably secured in a holder 130 of the main turret 108. As the glass tube 102 is aimed and moved through the plurality of processing stations 106, the glass tube 102 is heated and cooled. When heated to a high temperature, one or more outer surfaces 140 or inner surfaces 146 ( Figure 4 ) emits infrared radiation outward from the glass tube 102 in a radial direction, an axial direction, or other directions. Figure 6 ) toward the lens 506 of the thermal imager 122 ( Figure 6 ) reflects the infrared light. Alternatively, the thermal imager 122 may be positioned to directly capture the infrared light emitted from the glass tube 102 without using the reflector 124. The thermal imager 122 uses a plurality of sensors to capture the infrared light and outputs thermal image data including the wavelength and intensity of the infrared light received by the thermal imager 122. Fig. 9As shown in FIG. 1 , thermal image data output by the thermal imager 122 is transmitted from the thermal imager 122 to the processor 900 via a communication path 904 (which may be wired or wireless). The processor 900 receives the thermal image data, processes the thermal image data, and outputs one or more properties (e.g., temperature) of the glass tube 102 determined by processing the thermal image data.

[0133] In one or more embodiments, the thermal imaging system 120 may be configured to be used at a particular stage of the conversion process or at a processing station 106 (e.g., a heating station 202 ( Figure 2 ) at the start or end of the dwell time at the forming station 204 ( Figure 2 ), or other stages in the conversion process]. Thermal image data of the glass tube 102 can be captured at the beginning or end of the dwell time of a forming operation at a processing station 106, or other stages in the conversion process. Thermal image data can be captured at the beginning of the dwell time, in the middle of the dwell time, at the end of the dwell time, or while the glass tube 102 is being aimed and moved by the main turret 108 between one processing station 106 and a subsequent processing station 106.

[0134] Alternatively, in other embodiments, the thermal imaging system 120 may be configured to capture thermal image data of the glass tube 102 at set time intervals during any portion of the conversion process. As previously described, the thermal imager 122 may have an image capture rate in the range of from 30 Hz to 60 Hz. The overall capture rate of the thermal imaging system 120 may be defined as the rate at which the thermal imaging system 120 generates output data sets, and may include the capture rate of the thermal imager 122 and the time necessary to transmit thermal image data to the processor 900, process the thermal image data, and output the thermal image data to the memory module 902, the display 906, the process controller, or other devices. The minimum overall capture rate of the thermal imaging system 120 is the fastest rate at which the thermal imaging system 120 is able to capture, transmit, process, and output thermal image data. The minimum overall capture rate of the thermal imaging system 120 may generally be greater than or equal to about 10 Hz. In other embodiments, the minimum overall capture rate of the thermal imaging system 120 may be at least 20 Hz. For example, the minimum overall capture rate of the thermal imaging system 120 may be from 10 Hz to 50 Hz, from 10 Hz to 40 Hz, from 10 Hz to 30 Hz, from 10 Hz to 20 Hz, from 20 Hz to 50 Hz, from 20 Hz to 40 Hz, from 20 Hz to 30 Hz, from 30 Hz to 50 Hz, or from 30 Hz to 40 Hz. A minimum overall capture rate of the thermal imaging system 120 of at least 10 Hz may facilitate capturing very high temperature gradients generated during certain stages of the conversion process. In one or more embodiments, one or more data filters may be employed to increase the overall capture rate of the thermal imaging system 120. In one or more embodiments, the sampling rate may be adjusted to change the overall capture rate of the thermal imaging system 120.

[0135] Reference Figures 11A-11D , providing a thermal image captured by the imager. The areas with higher temperatures on the glass tube 102 are indicated as lighter in color, while the areas with lower temperatures are indicated as darker in color. Fig.11A FIG. 2 shows a preheating step in which the glass tube 102 is heated before being separated. Fig. 11B 1, the glass tube 102 is being cut and separated from the glass tube raw material. As indicated by the very brightly colored area between the two sections of the glass tube 102, the glass tube in the cutting area 1102 is at a very high temperature at the separation station 206. In some embodiments, the temperature of the glass tube 102 in the cutting area 1102 can reach a temperature of 1500° C. or higher. The contrast in color indicates a high temperature gradient from the cutting area 1102 toward the opposite end 1104 of the glass tube 102. Fig. 11C and 11D Thermal images captured during a forming operation in the shoulder 142 and flange 144 of a glass tube 102 being shaped into a vial are shown. Again, the color change contrast between the lighter color of the forming area (e.g., the shoulder 142 and flange 144) and the darker color moving toward the opposite end 1104 of the glass tube 102 indicates a high temperature gradient along the length L of the glass tube 102.

[0136] Available from Figures 11A-11D Temperature data can be extracted from a series of images similar to those of FIG. 1 to produce a temperature history of the glass tube 102 at any portion of the conversion process in the converter 100. The wavelength of infrared light captured in the thermal image is related to the temperature of the glass tube 102 emitting the particular wavelength of infrared light captured. Fig.10 , an example of the temperature history of the surface of a glass tube 102 processed by a converter 100 as captured by a thermal imaging system 120 is shown. Fig.10 1002 is shown as a first temperature 1002 of the glass tube 102 determined at a first portion of the surface of the glass tube 102. In addition, the thermal imaging system 120 can also be used to extract temperature information of different regions of the article [e.g., extracting the flange 144 (145) of the partially formed glass tube 102 during the formation of the flange 144 and the neck 145] Figure 3A ) and neck 145( Figure 3A ) area temperature information]. Fig.10 , a second temperature 1004 is determined at a second portion of the surface of the glass tube 102, and a third temperature 1006 is determined at a third portion of the surface of the glass tube 102. In some embodiments, the second temperature 1004 and the third temperature 1006 may be determined at portions of the glass tube 102 corresponding to the flange 144 and the neck 145, respectively.

[0137] Operational experience with the tube component converter 100 has shown that the mutual influences in the conversion process are very strong, meaning that a small change in temperature at one processing station 106 of the converter 100 can affect the glass temperature and the forming process equally across the entire converter 100. The thermal imaging system 122 allows monitoring of the temperature of a single glass tube 102 passing through all of the processing stations 106 as well as the operations performed in each processing station 106, so that the effects of temperature changes at one processing station 106 on downstream forming operations can be observed and studied. Because the thermal imaging system 120 travels with the main turret 108 during the sighting movement between processing stations 106, the thermal imaging system 120 is also able to capture thermal images of the glass tube 102 between processing stations 106 to study the effects of cooling of the glass tube 102 between processing stations 106.

[0138] Refer again Figures 7A-7G As previously described, the thermal imaging system 120 may be configured to obtain thermal imaging data of the outer surface 140 of the glass tube 102. In addition, the thermal imaging system 120 may be configured to obtain thermal imaging data of one or more inner surfaces 146 ( Figure 4 ) of the glass tube 102 through temperatures of several hundred degrees Celsius (i.e., 200° C. to 300° C. or higher). Figure 4 ) has been measured. In addition, in one or more embodiments, the temperature measurement of the inner surface 146 of the glass tube 102 can facilitate the identification of temperature ranges that cause quality defects. For example, during the flange forming operation at the forming station 204 of the converter 100 for manufacturing vials, the flange 144 ( Figure 3D ) may develop at certain internal surface temperatures. The act of measuring the internal surface temperature of the glass tube 102 can be used to identify these internal surface temperatures that cause cracks so that changes can be made to the conversion process to prevent cracks.

[0139] Multiple mirror paths may be configured to obtain an inner surface 146 ( Figure 4 ). As previously described, the thermal imaging system 120 may be configured to acquire thermal images of an end view of the glass tube 102 using a plurality of stationary reflectors 700. The end view of the open end of the glass tube 102 may allow the thermal imaging system 120 to determine one or more internal temperatures of the glass tube 102, such as the temperature of the inner surface 146 of the glass tube 140. To capture the end view of the open end of the glass tube 102, one or more stationary free-standing thermal imaging devices (not shown) may be mounted directly below one or more processing stations 106 of the converter 100. The optical centerline of the stationary thermal imaging device may be aligned with the centerline C of the glass tube 102. LThe thermal imaging device 700 may be aligned to capture an end view of the glass tube 102. It may be expensive and cost prohibitive to install multiple individual thermal imaging devices below the multiple processing stations 106. In another configuration, a stationary imaging device (not shown) may be installed at a radially outward position relative to the processing station 106, and a stationary reflector 700 may be installed below the processing station 106 to reflect an end view image of the glass tube 102 to a lens (not shown) of the thermal imaging device. In this configuration, multiple thermal imaging devices may be necessary to capture thermal data of the inner surface 146 of the glass tube 102 at different processing stations 106.

[0140] Alternatively, in one or more embodiments, the thermal imaging system 120 previously described herein coupled to the main turret 108 may be used in conjunction with one or more stationary reflectors 700 that may be positioned below one of the plurality of processing stations 106. As shown in FIG. 7, the reflector 124 may be positioned to reflect infrared light emitted radially outward from the outer surface 140 of the glass tube 102 toward the lens 506 of the thermal imager 122, and the stationary reflector 700 may be positioned to reflect infrared light emitted axially downward (i.e., at a position approximately equal to the centerline C of the glass tube 102) from the inner surface 146 of the glass tube 102 toward the lens 506 of the thermal imager 122. L 104. When the thermal imager 122 is moved with the main turret 108 to align (e.g., angularly align) with the stationary reflector 700, both the reflector 124 and the stationary reflector 700 can reflect infrared light toward the lens 506 of the thermal imager 122, allowing the thermal imager 122 to simultaneously capture thermal images of the outer surface 140 and the inner surface 146 of the glass tube 102. Fig.12 A thermal image taken with thermal imaging system 120 having mirror 124 and stationary mirror 700 is depicted. Fig. 9 The thermal image of 140 shows a single thermal image that simultaneously captures thermal data for the exterior surface 140 and thermal data for the interior surface 146. The single thermal image may allow the thermal imaging system 120 to determine one or more exterior surface temperatures and one or more interior temperatures from a single set of thermal image data. Although described using a combination of the reflector 124 and the stationary reflector 700, as previously described in this disclosure, the act of capturing infrared light emitted from the interior surface 146 of the glass tube 102 may be accomplished by positioning the reflector 124 to reflect infrared light from both the exterior surface 140 and the interior surface 146 of the glass tube 102 toward the thermal imager 122 or by coupling a supplemental reflector 125 to the mounting device 126 to reflect infrared light from the interior surface 146 of the glass tube toward the thermal imager 122.

[0141] Although the thermal imaging system 120 has been described with respect to a vertically oriented converter 100 (where the central axis A of the main turret 108 is generally perpendicular to the ground), it should be understood that the thermal imaging system 120 can also be adapted for use with a horizontally oriented converter or an inclined converter. The thermal imaging system 120 is also described herein with respect to a converter 100 having a generally circular main turret 108 for aiming the glass tube 102 around a generally circular main loop 116 of processing stations 106, but it should be understood that the thermal imaging system 120 can be used with a converter 100 having any non-circular continuous loop or trajectory for aiming the glass tube 102 through a plurality of processing stations 106. The processing stations 106 can be arranged in any convenient pattern. As previously described, it should also be understood that the thermal imaging system 120 can be used with a vial converter 100 and converters for producing other articles (such as barrels, ampoules, syringes, or other glass articles) from a glass tube 102.

[0142] The thermal imaging system 120 described in the present disclosure can assist in the development of process measurements, mathematical models, and experiments to establish a fundamental understanding and glass-centric characterization of the converter 100 and the conversion process performed therewith. By using the thermal imaging system 120 to develop a better understanding of the conversion process, reliance on skill and experience is reduced in guiding the converter 100 setup, tooling, process configuration, and ability to successfully transfer between conversion platforms. The thermal imaging system 120 also allows for quantitative mapping of process windows and process limits. The thermal imaging system 120 allows for automated analysis of thermal images and location of the centerline C of the glass tube 102 and / or articles manufactured therefrom. L Additionally, the thermal imaging system 120 makes it easier to adapt the converter 100 and the conversion process to accommodate alternative glass formulations.

[0143] The thermal imaging system 120 also provides process temperature measurements that can be incorporated into the control system used to control the converter 100. At a particular processing station 106, measurements of the surface temperature of the glass tube 102 moving through the processing station 106 indicate significant short-term and long-term variability in the surface temperature of the glass tube 102. The short-term variability in the surface temperature of the glass tube 102 (which is variability from one individual segment to the next) can be attributed to manufacturing tolerances in the tube drawing process, which cause tube dimensions [e.g., tube diameter W ( Figure 4 ) and wall thickness T( Figure 4 )] along the length L of the glass tube 102 raw material. The quality variability from tube to tube can be from + / -2.5 percent (%) to + / -5%. The heating element 301 ( Figure 3A) are positioned to heat a specific area of ​​the glass tube 102. Thus, changes in glass quality in that specific area, which may be caused by these manufacturing variations of each glass tube 102, directly result in corresponding changes in the surface temperature of the glass tube 102. Other factors, such as uncertainties and variations in machine timing, may also cause short-term changes in surface temperature, but manufacturing variations in the glass tube 102 raw material have the most significant impact on these short-term changes. Conventional converters do not have systems to compensate for these short-term changes in the surface temperature of the glass tube 102.

[0144] Long term variations in the surface temperature of the glass tube 102 (i.e., measured over minutes and / or hours from one cycle to the next) may be caused by a number of factors that induce changes to the thermal state of the conversion process. Conditions that may cause long term variations in the glass surface temperature may include machine warm-up as the converter 100 is ramped from ambient conditions to steady state operating conditions. The warm-up process may take from 2 hours to 12 hours. Long term variability in surface temperature may also be caused by changes in fuel heating value (changes in the composition of the fuel gas received from the natural gas supplier), burner 302 degradation, changes in manifold pressures (e.g., fuel gas, air, oxygen), ambient conditions, exhaust hood flow rate variability, other factors, and / or a combination of factors. Conventional converter systems must be manually adjusted to account for these long term variations in surface temperature.

[0145] Reference Fig.13 , discloses a control system 1300 for a glass tube converter 100 that can provide systems and methods for compensating for short-term and long-term variations in surface temperature to provide more consistent, efficient operation of the converter 100. The control system 1300 includes the converter 100, the thermal imaging system 120, and a controller 1302.

[0146] The converter 100 may have any of the features of the converter 100 previously described herein. As previously described, the one or more heating stations 202 may include a heating element 301 that can be manipulated to change the amount of heating of the glass tube 102 and thereby change the temperature of the glass tube 102. For example, in some embodiments, the heating element 301 may be a burner 302 having a fuel control valve 310, an oxygen control valve 312, and an optional combustion air control valve 314, all of which control valves can be manipulated to change the heat of the flame produced by the burner 302 and thereby change the temperature of the glass tube 102 as it is aimed and moved through the heating station 202. Alternatively, in other embodiments, the heating element 301 may be a laser, such as a carbon dioxide laser, for example. The power input to the laser, the time the glass tube 102 is exposed to the laser, or both can be manipulated to change the degree of heating of the glass tube 102 and thereby change the temperature of the glass tube 102. Reference Figure 3E As previously described, the converter 100 may also have one or more cooling stations 210, which may include one or more cooling fluid control valves 344 to control the mass flow rate of the cooling fluid 342, which may also affect the temperature of the glass tube 102 aimed at moving through the cooling station 210.

[0147] The thermal imaging system 120 may be used to measure and determine one or more process variables for use by the control system 1300. The thermal imaging system 120 may have any of the features described herein with respect to the thermal imaging system 120 coupled to the main turret 108 for rotation therewith. As previously described, the thermal imaging system 120 includes at least one thermal imager 122, a processor 900 communicatively coupled to the thermal imager 122, and one or more memory modules 902 having machine-readable instructions thereon for receiving and processing thermal image data captured by the thermal imager 122. The thermal imaging system 120 may also include at least one reflector 124 positioned to reflect infrared light from the glass tube 102 toward the thermal imager 122. In certain embodiments, a single processor may serve as both the controller 1300 of the control system 1300 and the processor 900 of the thermal imaging system 120. The thermal imaging system 120 may also have one or more stationary reflectors 700 ( FIG. 7 ) vertically positioned below one or more processing stations 106 to reflect light reflected by the inner surface 146 ( FIG. 14 ) of the glass tube 102 toward the thermal imager 122 as the thermal imager 122 is aimed and moved into position to receive light reflected from the stationary reflectors 700. Figure 4 In one or more embodiments, a plurality of thermal imagers 122 may be coupled to the main turret 108 to simultaneously measure process variables of a plurality of processing stations 108 or secondary processing stations 112.

[0148] The thermal imaging system 120 may output one or more process variables that may be used by the control system 1300 to control the converter 100 and the conversion process. Alternatively, the thermal imaging system 120 may store the one or more process variables to the memory module 902 for retrieval by the controller 1302. In one or more embodiments, the process variables determined by the thermal imaging system 120 may include one or more temperatures of the outer surface 140 of the glass tube 102 at one or more points on the outer surface 140 of the glass tube 102 and at one or more stages of the conversion process. In some embodiments, the process variables determined by the thermal imaging system 120 may include one or more temperatures of the inner surface 146 of the glass tube 102 at one or more points on the inner surface 146 of the glass tube 102 and at one or more stages of the conversion process. Figure 4). In some embodiments, the process variable may be the peak centerline glass temperature (i.e., the temperature of the glass tube 102 along the centerline C of the glass tube 102). L In other embodiments, the process variable may also be one or more dimensions of the glass tube 102 at one or more regions of the glass tube 102, the viscosity of the glass tube 102 at one or more regions of the glass tube 102, the temperature distribution of the glass tube 102 as a function of time, other characteristics of the glass tube 102, or a combination of these items.

[0149] The control system 130 may receive other process variables of the converter 100. For example, the control system 130 may receive information about the dimensions or other physical properties of the glass tube 102, such as the outer diameter, inner diameter, and / or thickness. The dimensions or other process variables of the glass tube 102 may be received by the control system 130 from an external source or from other measurement systems integrated with the converter 100 and / or the control system 130. Fig.13 In certain embodiments, the control system 1300 may include a sizing system 1310 for measuring the diameter W and thickness T of the glass tube 102 and determining the glass mass per unit length of the glass tube 102 from the diameter W, thickness T, and density of the glass. Any of the diameter W, thickness T, or glass mass per unit length of the glass tube 102 may be used by the control system 1300 as a process variable.

[0150] The dimension determination system 1310 may include at least one of a visual imaging system, a laser reflectometer, a laser measuring instrument, other measuring equipment, or a combination of these items. Alternatively, the dimension determination system 1310 may include an optical micrometer, such as a micrometer including a collimated light beam emitted from a light source on one side of the glass tube 102 and a light receiver (such as a camera or a light sensor, for example) positioned on the opposite side of the glass tube. Fig.13 As shown in FIG. 1 , in some embodiments, the sizing system 1310 may include a visual imaging system 1312 having a visual imaging device configured to capture a visual image of the glass tube 102. In some embodiments, the visual imaging device of the visual imaging system 1312 may be stationary and focused on a single processing station 106. In some embodiments, the visual imaging system 1312 may be coupled to the base 104 of the converter 100. In some embodiments, the visual imaging system 1312 may be positioned directly above the main loop 116 ( Figure 2 ) in the last forming station 204 ( Figure 2). Alternatively, in other embodiments, the visual imaging system 1312 may be positioned at the processing station 106 located before the first forming station 204 of the converter 100. In other embodiments, the visual imaging system 1312 may be positioned to capture a visual image of the glass tube 102 before the glass tube 102 is loaded into the holder 130. The visual image obtained from the visual imaging system 1312 may be used to obtain the outer diameter W of the glass tube 102.

[0151] In certain embodiments, the sizing system 1310 may further include a laser reflectometer 1314 fixed at a stationary position relative to the base 104 of the converter 100. The laser reflectometer 1314 may be oriented to measure the thickness T (i.e., wall thickness) of the glass tube 102 at a single processing station 106. In one or more embodiments, the laser reflectometer 1314 may be located at the same processing station 106 as the visual imaging system 1312. Alternatively, the laser reflectometer 1314 may be located at a processing station 106 different from the processing station 106 to which the visual imaging system 1312 is directed. In certain embodiments, the visual imaging system 1312 may be positioned and oriented to capture a visual image of the glass tube 102 (e.g., an end view of the glass tube 102), from which the outer diameter W and the inner diameter of the glass tube may be determined. The visual imaging system 1312 may then use the outer diameter and the inner diameter of the glass tube 102 to determine the thickness T and the mass per unit length of the glass tube 102. Although the sizing system 1310 is described herein as having a visual imaging system 1312 , a laser reflectometer 1314 , or both, it is contemplated that other sizing devices may be incorporated into the sizing system 1310 to determine the dimensions and mass per unit length of the glass tube 102 .

[0152] In alternative embodiments, one or more portions of the sizing system 1310 (e.g., the visual imaging system 1312, a laser reflectometer, or other sizing equipment) may be positioned upstream of the processing station 106 of the converter 100 to measure the size of the glass tube feedstock prior to feeding the glass tube feedstock to the converter 100. For example, the sizing system 1310 may be positioned at a tube loading device [e.g., a glass tube loading turret 110 ( Figure 1 ) or a glass tube loading arm (not shown)] to measure the size of the glass tube 102 before loading the glass tube 102 into the converter 100.

[0153] The sizing system 1310 may further include a sizing processor 1316 having one or more sizing memory modules 1318 having machine-readable instructions thereon that, when executed by the sizing processor 1316, cause the sizing system 1310 to receive measurement data from at least one sizing device, process the measurement data, and determine the diameter W and thickness T of the glass tube from the measurement data. For example, in certain embodiments, the machine-readable instructions, when executed by the sizing processor 1316, may cause the sizing system 1310 to receive visual image data from the visual imaging system 1312, receive thickness information from the laser reflectometer 1314, process the visual image data, determine the diameter W of the glass tube 102, process the thickness information from the laser reflectometer 1314, and determine the thickness T of the glass tube 102. Alternatively, in other embodiments, the machine-readable instructions, when executed by the sizing processor 1316, may cause the sizing system 1310 to receive visual image data from the visual imaging system 1312, determine the outer diameter W of the glass tube 102, determine the thickness, and determine the mass per unit length of the glass tube 102 from the thickness T and the outer diameter W. The machine-readable instructions may include commercially available visual image processing software, such as those image processing programs previously described. The machine-readable instructions, when executed by the sizing processor 1316, may cause the sizing system 1310 to store and / or output the thickness T and the diameter W of the glass tube 102. In some embodiments, the machine-readable instructions, when executed by the sizing processor 1316, may cause the sizing system 1310 to determine the glass mass per unit length of the glass tube 102 (i.e., the mass per unit length of the glass tube 102) from the measured diameter W and thickness T of the glass tube 102. The sizing system 1310 may store the mass per unit length of the glass tube in the one or more sizing memory modules 1318 or may output the mass per unit length of the glass tube 102 .

[0154] In some embodiments, the control system 1300 can determine a temperature gradient across the thickness T of the glass tube 102 from the thickness T determined by the sizing system 1310 and the surface temperature (e.g., the temperature of the outer surface 140 and the inner surface 146 of the glass tube 102) determined by the thermal imaging system 120. The temperature gradient can be used as a process variable in one or more control methods. In certain embodiments, the control system 130 can determine a viscosity gradient of the glass across the thickness T of the glass tube 102 from the temperature information from the thermal imager 122 and the thickness T of the glass tube 102 determined by the sizing system 1310. The viscosity gradient can be used as a process variable in certain embodiments. Process variables can also include the aiming movement time of the turret.

[0155] Still refer to Fig.13, a controller 1302 of the control system 1300 may include a control processor 1304 and one or more control memory modules 1306 having machine readable instructions thereon that, when executed by the control processor 1304, cause the control system 1300 to implement one or more control methods for controlling the converter 100, which control methods will be further described herein. The controller 1302 may have a plurality of inputs communicatively coupled to one or more of the thermal imaging system 120, the sizing system 1310, or other sensors. The controller 1302 may have a plurality of outputs communicatively coupled to one or more control devices, which may include a fuel control valve 310, an oxygen control valve 312, an air control valve 314, a cooling fluid control valve 344 ( Figure 3E ), forming tool actuator 326 ( Figure 3D ) or one or more of other control devices associated with one or more heating stations 202, forming stations 204, cooling stations 210, or other processing stations 106. In some embodiments, the controller 1302 may be a proportional-integral-derivative (PID) controller.

[0156] The machine-readable instructions stored in the one or more control memory modules 1306, when executed by the control processor 1304, may cause the control system 1300 to receive process variables (e.g., temperature, viscosity, dimensions, temperature gradient, viscosity gradient, other characteristics or combinations of characteristics of the glass tube 102) from the thermal imaging system 120, compare the process variables to set points stored in the memory, determine controlled variables based on the comparison of the process variables to the set points, and transmit control signals representing the controlled variables to the one or more control devices. In some embodiments, the controller 1302 may receive one or more process variables (e.g., diameter W, thickness T, and / or mass of glass per unit length of the glass tube 102) from the sizing system 1310. In one or more embodiments, the machine-readable instructions, when executed by the control processor 1304, may cause the controller 1302 to retrieve process variables from the thermal imaging system 120, the sizing system 1310, or other sensors or sensing systems.

[0157] The set point of the process variable can be determined from a database of historical process variable measurements collected during operation of the converter 100. In some embodiments, the database may include process variable measurements and operating conditions representing acceptable production conditions. In some embodiments, the database may include a data set of process variable measurements and operating conditions corresponding to a representative cycle, which is collected to characterize the typical variability of the converter 100. The process variable measurements in the database can be used to form the set point of the one or more process variables. The variability of the process variable measurements can be determined from the database to define control parameters (for example, such as one or more gain constants) to maximize thermal consistency and avoid over-control of the converter 100. In some embodiments, the set point can be calculated as a moving average of the process variables acquired within a specific time (for example, a time of at least 3 minutes, at least 30 minutes, at least 60 minutes, at least 3 hours, at least 10 hours, or even at least 3 days).

[0158] Now refer to Fig.14 , schematically depicts one embodiment of a temperature feedback control method 1400. A process variable 1402 of the converter 100 is measured and transmitted to the controller 1302. The control processor 1304 of the controller 1302 compares the process variable 1402 to the set point 1404 and calculates an error 1406, which may be the difference between the set point 1404 and the process variable 1402. The control processor 1304 may then calculate one or more controlled variables 1408 and transmit one or more control signals representing the controlled variables 1408 back to the converter 100 (particularly to the control device 1410 of the converter 100). In some embodiments, the process variable 1402 may be one or more temperatures of the glass tube 102 measured by the thermal imaging system 120. In certain embodiments, the temperature of the glass tube 102 may be used by the controller 1302 to control the heating station 202 ( Figure 3A ) to control the heating of the glass tube 102 at the heating station 202. The control processor 1304 may calculate the controlled variable 1408 using one or more proportional, integral, or differential calculation methods. The calculation of the controlled variable 1408 may include applying a gain constant 1409 to the controlled variable 1408 to adjust the sensitivity of the conversion process to changes in the controlled variable 1408. Specifically, in some embodiments, the controlled variable 1408 may be determined by multiplying the error 1406 by the gain constant 1409. Alternatively, the control processor 1304 may combine modeling (for example, such as thermal conductivity modeling), system-level control methods, or other control strategies to determine the controlled variable 1408.

[0159] The temperature measured by the thermal imaging system 120 may be a single temperature of the glass tube 102 taken at a particular location on the glass tube 102 at a particular stage of the conversion process, such as a cycle end temperature, a dwell end temperature (i.e., the temperature of the glass tube 102 at the end of operation in the previous processing station 106 just before the main turret 108 aims the glass tube 102 to move to the next processing station 106), a dwell start temperature (i.e., the temperature of the glass tube 102 at the processing station 106 at the beginning of the dwell time), or any other temperature of the glass tube 102 at any location on the glass tube 102 and at any stage of the conversion process. In certain embodiments, the temperature measured by the thermal imaging system 120 may be a cycle end maximum centerline temperature and / or a maximum centerline temperature at any processing station 106. The process variables 1402 may include the outer surface 140 ( Figure 4 ) or the temperature of the inner surface 146 ( Figure 4 In some embodiments, the process variables 1402 may include one or more average temperatures, such as, for example, an average centerline temperature of the glass tube 102.

[0160] In some embodiments, the process variable 1402 may be the difference between any two temperatures of the glass tube 102 measured by the thermal imaging system 120. For example, in some embodiments, the process variable 1402 may be the temperature of the processing station 106 ( Figure 1 ) (e.g., heating station 202 or forming station 204) and the centerline temperature of the glass tube 102 at the end of the dwell time at the same processing station 106. In certain embodiments, process variable 1402 can be the difference between the end-of-cycle temperature of the glass tube 102 (i.e., the temperature of the glass tube 102 measured at the end of the last processing station of the conversion process) and the start-of-cycle temperature of the glass tube 102 (i.e., the temperature of the glass tube 102 measured at the first processing station of the conversion process). Process variable 1402 can be the same holder position 136 ( Figure 2 ) of the glass tube 102 at different stages of the conversion process. Alternatively, the process variable 1402 may include a difference between the temperature at one location on the glass tube 102 and the temperature at a second location on the glass tube 102 at the same stage of the conversion process. For example, the process variable 1402 may include the temperature of the outer surface 140 ( Figure 4 ) is the same as the temperature of the inner surface 146 ( Figure 4). The process variable 1402 may represent a temperature gradient between two locations on the glass tube 102, such as a temperature gradient across the thickness T of the glass tube 102. The process variable 1402 may also be an actual dimension of the glass tube 102 determined from the thermal imaging data. The process variable may also be a viscosity of the glass tube 102 or a viscosity gradient across the thickness T of the glass tube 102. The process variable 1402 may be any other process variable or characteristic of the glass tube 102 described herein.

[0161] The process variable 1402 (e.g., the temperature of the glass tube) may be compared to a set point 1404, which may be stored in the one or more control memory modules 1306 of the controller 1302. The set point 1404 may be periodically updated in the control memory module 1306 based on changes observed from the process variable 1402 measurements and the ongoing accumulation of operating conditions in the operating condition database described above.

[0162] In certain embodiments, the controlled variables 1408 may include one or more variables that affect one or more heating stations 202 ( Figure 3A ) in the heating element 301 ( Figure 3A ) heating of the glass tube 102. For example, in some embodiments, the controlled variables 1408 may include one or more burners 302 ( Figure 3A ) of the fuel control valve 310 ( Figure 3A )、Oxygen control valve 312( Figure 3A ) and air control valve 314 ( Figure 3A ) The fuel control valve 310, oxygen control valve 312, and / or optional air control valve 314 of one or more heating stations 202 are communicatively coupled to the output of the controller 1302, so that the controller 1302 can manipulate the mass flow rate of fuel gas delivered to the one or more burners 302 (FIG. 3) while proportionally varying the flow rates of oxygen and / or air, thereby controlling the heating station 202.

[0163] In certain embodiments, the ratio of the mass flow rate of oxygen and / or air to the mass flow rate of the fuel gas may be fixed, constant, such that adjusting the mass flow rate of the fuel gas changes the corresponding mass flow rate of oxygen and / or air. In these embodiments, the controller 1302 may be configured to manipulate the fuel control valve 310, the oxygen control valve 312, and / or the air control valve 314 to maintain a constant stoichiometric ratio of the fuel gas delivered to the burner. For example, in embodiments where air and pure oxygen are provided to the burner, the ratio of the air flow to the pure oxygen flow must also be maintained to maintain stoichiometry. In the case where the combustion of the burner is fed by multiple streams (e.g., air and oxygen), the air and pure oxygen mass flow rates are both maintained at a constant ratio to maintain a constant oxidant concentration (which refers to the total oxygen concentration of the air and oxygen streams combined) at the burner 302. Thus, in embodiments where fuel gas, pure oxygen, and air are supplied to the burner 302, the stoichiometry of the oxidation of the fuel gas is maintained by maintaining a ratio of the fuel gas flow rate to the pure oxygen flow rate and by maintaining a ratio of the air flow rate to the pure oxygen flow rate. In operation, the controller 1302 may send a control signal to the fuel control valve 310 to vary the mass flow rate of the fuel gas delivered to the burner 302. To maintain the stoichiometry, the controller 1302 will also make corresponding changes to the pure oxygen flow rate and the air flow rate to maintain a constant ratio of the air flow rate to the pure oxygen flow rate and a constant ratio of the fuel gas flow rate to the pure oxygen flow rate. Maintaining a constant stoichiometric ratio of the fuel gas delivered to the burner 302 will maintain the heat level of the burner 302 in proportion to the increase in fuel flow, which may increase the predictability of the temperature control response to changes in the controlled variable 1408.

[0164] Alternatively, in other embodiments, the mass flow rate of the fuel gas and the mass flow rate of oxygen and / or air may be adjusted independently of each other, such that the ratio of oxygen and / or air to the fuel gas may be adjusted in response to a control signal from the controller 1302. For example, the act of adjusting the ratio of the fuel gas to the oxidant introduced to the burner 302 at the heating station 202 may be used to adjust the amount of heating performed at the heating station 202 and thus affect the temperature of the glass tube 102. In certain embodiments, the fuel control valve 310 may be controlled to control the heating in the heating station 202, and the oxygen control valve 312 and / or the air control valve 314 may be controlled to maintain a constant stoichiometric ratio of the fuel gas to the oxygen at the burner 302 of the heating station 202. Furthermore, in a heating station 202 having multiple burners 302, the ratio of the fuel gas mass flow rate between the respective burners 302 may be fixed, such that a change in the fuel gas mass flow rate of a burner 302 causes a proportional change in the fuel gas mass flow rate of another burner 302. In some embodiments, each burner 302 may be independently controlled by the controller 1302. In alternative embodiments, the heating station 202 may include one or more laser heating elements, and the controlled variable 1408 may be the power output delivered to the laser or the time that the glass tube 102 is exposed to the laser.

[0165] can be achieved by performing the following steps at individual processing stations 106 ( Figure 1 ) to determine the gain constant 1409. Generally speaking, bump testing refers to a process in which small changes are made to one or more controlled variables 1408 and the process variables 1402 are measured to determine the response of the process variables 1402 to the small changes in the controlled variables 1408. For example, the mass flow rate of the fuel gas and / or oxygen may be changed in very small increments, and the thermal imaging system 120 may be used to measure the thermal response of the converter 100 to the changes in the mass flow rate of the fuel and / or oxygen. For the glass converter 100, the heating station 202 ( Figure 2 ) is highly coupled so that individual crash tests can be performed for each heating station 202 while keeping changes in the mass flow rates of fuel and oxygen very small.

[0166] Fig.14 The feedback control method 1400 described in FIG. 1 may be used to control the main turret 108 ( Figure 1 ) to maintain a consistent surface temperature of the glass tube 102 when averaged over a period of 2 to 3 complete rotations of the glass tube 102. Fig.14 The feedback control method 1400 is used to configure the control system 1300 to maintain a consistent surface temperature, which can reduce or eliminate the effects of the long-term sources of surface temperature variability previously described.

[0167] However, the feedback control method 1400 may not be effective in reducing or eliminating short-term variations, such as those in the mass of glass per unit length of the glass tube 102 as previously described. For example, for a converter 100 having N processing stations 106 and a thermal imaging system 120 having a single thermal imager 122, the thermal imager 122 may measure the process variable 1402 (i.e., temperature) of a single glass tube 102 as it is sighted through the N processing stations 106. The controlled variable 1408 would then be adjusted based on the temperature of the single glass tube 102, and this adjustment would be maintained for the next (N-1) glass tubes 102 until the thermal imager 122 cycles back to measure the process variable 1402 again. Thus, the operating conditions are maintained constant for the (N-1) glass tubes 102 between cycles of the thermal imager 122. For larger converters 100 having more than 18 processing stations 106, such as 36 or more stations, controlling the converter 100 in response to one measurement of the process variable 1402 for one of every N glass tubes 102 may not account for short-term variability in the process. Additionally, the size and / or mass of the (N-1) glass tubes 102 may vary, which may introduce more variability into the process between cycles of the thermal imager 122. In certain embodiments, the thermal imaging system 120 may include multiple thermal imagers 122 distributed around the holder location. Adding multiple thermal imagers 122 may increase the frequency of measurement of the process variable 1402 and may improve control of the converter 100.

[0168] Alternatively, to account for short-term changes (e.g., changes in the mass of glass per unit length of the glass tube 102), the control system 1300 ( Fig.13 ) implements the cascade control method 1500 (e.g. Fig.15 106). In the cascade control method 1500, a second process variable 1516 may be measured for at least (N-1) glass tubes 102 between cycles of the thermal imager 122 or provided from an external source. The cascade control method 1500 provides the ability to compensate for short-term variations (e.g., changes in glass tube mass and / or size) on a tube-by-tube basis. Thus, the cascade control method 1500 may allow the control system 1300 to compensate for temperature changes at holder locations where the temperature is not measured by the visual imaging system 120. The cascade control method 1500 may provide improved and / or enhanced process control of the converter 100 compared to the feedback control method 1400 (which may rely on measurement of a process variable by the thermal imaging system 120 once each time the thermal imager 122 cycles through the processing station 106).

[0169] Reference Fig.15, in the first feedback loop 1502, a first process variable 1506 of the conversion process is measured and transmitted to the controller 1302. The controller 1302 compares the first process variable 1506 with a first set point 1508 associated with the first process variable 1506 and calculates a first error 1510, which may be a difference between the first set point 1508 and the first process variable 1506. The controller 1302 may then calculate an intermediate controlled variable (not shown) and adjust the intermediate controlled variable by applying a first gain constant 1514. In the second feedback loop 1504, a second process variable 1516 of the converter 100 is measured and transmitted to the controller 1302. The controller 1302 compares the second process variable 1516 with a second set point 1518 associated with the second process variable 1516 and calculates a deviation (i.e., a second error, not shown). The controller 1302 may then use the deviation and the second gain constant 1522 to adjust the controlled variable 1512 (which is determined by the controller 1302 in the first feedback loop 1502) to produce the controlled variable 1512. The controller 1302 may then transmit one or more control signals representing the controlled variable 1512 to one or more control devices 1410 of the converter 100.

[0170] In some embodiments, the first process variable 1506 may be one or more temperatures of the glass tube 102 measured by the thermal imaging system 120, and the second process variable 1516 may be an actual dimension of the glass tube 102 (e.g., diameter, thickness, or mass of glass per unit length of the glass tube 102, for example) measured by the sizing system 1310. The temperature of the glass tube 102 and the physical dimensions of the glass tube 102 may be used by the controller 1302 in the cascade control method 1500 to control the heating behavior at one or more heating stations 202 (Fig. A). The first feedback loop 1502 with the first process variable 1506 (which is the temperature of the glass tube 102) may allow the control system 1300 to control the converter 100 on a per cycle basis to reduce or eliminate the effects of long-term sources of surface temperature variability as previously described. A second feedback loop 1504 having a second process variable 1516, which is the actual size of the glass tube 102, can allow the control system 1300 to control the converter 100 on a per glass tube basis to reduce or eliminate the effects of short-term sources of surface temperature variability (e.g., variability in the size of the glass tube 102) as previously described herein.

[0171] In one or more embodiments, the first feedback loop 1502 of the cascade control method 1500 may be coupled to Fig.14 Described in and previously with Fig.14Similarly, the first process variable 1506, the first set point 1508, the first gain constant 1514, and the controlled variable 1512 may be the same as previously described with respect to the feedback loop. Fig.14 The process variable 1402, set point 1404, gain constant 1409, and controlled variable 1408 described in association are similar.

[0172] Refer back Fig.15 , the second process variable 1516 (which may be a physical property of the glass tube 102) may be measured by the sizing system 1310 ( Fig.13 ) measurements and / or calculations. A second process variable 1516 (e.g., diameter, thickness, or mass of glass per length of glass tube) may be compared to a second set point 1518 (which may be stored in the one or more control memory modules 1306 of the controller 1302). In some embodiments, the second set point 1518 may be a nominal mass per unit length of tube. The second set point 1518 may be periodically updated in the control memory module 1306 based on changes observed from process variable measurements and ongoing accumulation of operating conditions in a database. A deviation (not shown) may be calculated for each glass tube 102 being processed, and the controlled variable 1512 may be adjusted on a tube-by-tube basis. The deviation may be calculated using a mathematical model that relates the mass per unit length of the glass tube 102 to the temperature distribution of the glass tube 102. The mathematical model may include a heat transfer model, or may be empirically determined from historical thermal data stored by the thermal imaging system 120.

[0173] As previously described, the controlled variables 1512 may include the fuel control valves 310 ( Figure 3A )、Oxygen control valve 312( Figure 3A ) and / or air control valve 314 ( Figure 3A ) in one or more locations.

[0174] Refer again Fig.13 As described herein, the thermal imaging system 120 follows the single glass tube 102 through the converter 100, such that at a fixed position 138 on the main turret 108 corresponding to the thermal imaging system 120, the control system 1300 operates in full cascade mode (i.e., according to Fig.15 1500). However, for the glass tube 102 at the holder position 136 that does not correspond to the fixed position 138 of the thermal imaging system 120, the control system 1300 can be operated as a single loop feedback control method in which the feedback control is based on the second process variable 1516 ( Fig.15) to control the heating station 202, the second process variable may be a physical property of the glass tube 102 (e.g., the diameter, thickness, or mass of glass per unit length of the glass tube 102). The heating flow rate is continuously modified based on the physical property of the glass tube for the holder positions 136 between the fixed positions 138 of the thermal imaging system 120. As previously described, in one or more embodiments, more than one thermal imaging system 120 may be coupled to the main turret 108 of the converter 100 to provide measurements of the first process variable 1506 at two fixed positions 138 on the main turret 108, which allows the first process variable 1506 to be measured at a frequency greater than once per cycle.

[0175] Reference Fig.16 , depicts an embodiment of a single-loop feedback control method 1600 based on controlling the heating station 202 ( Figure 3A ) of one or more heating elements 301 ( Figure 3A ), which controls the change in glass mass per unit length of the glass tube 102 as measured by the sizing system 1310. Fig.16 In an embodiment of the present invention, the process variable 1602 may be a physical property of the glass tube 102, such as the diameter, thickness, or mass of glass per unit length of the glass tube 102. The process variable 1602 may be compared to a set point 1604, which may be a nominal diameter, nominal thickness, or nominal mass of glass per unit length of the glass tube 102. An error 1606 (which may be the difference between the process variable 1602 and the set point 1604) and a gain constant 1609 may be used to determine a controlled variable 1608, which may be a position of one or more of the fuel control valve 310, the oxygen control valve 312, and / or the air control valve 314, which in combination control the mass flow rate of fuel, oxygen, and / or air to the burners 302 (FIG. 3) of one or more heating stations 202. Fig.16 The single-loop feedback control method 1600 may represent the control system 1300 ( Fig.13 ) is directed to the operation of the glass tube 102 in a holder position 136 other than the fixed position 138, which is the holder 130 where the thermal imaging system 120 is located. At the fixed position 138, the control system 1300 is as previously described and Fig.15 is shown operating in full cascade mode.

[0176] In certain embodiments, for Figure 14-16 For any of the control methods depicted in FIG. 1 , the controlled variable 1408, 1512, 1608 may be the position of the cooling fluid control valve 344, which controls the cooling fluid delivered to one or more cooling stations 210 ( Figure 3E) of cooling fluid 342( Figure 3E ) mass flow. In these embodiments, the cooling fluid control valve 344 ( Figure 3E ) may be communicatively coupled to the control system 1300. Additionally, in some embodiments, the controlled variables 1408, 1512, 1608 may also include a time for aiming movement of the main turret 108 of the converter 100.

[0177] In some embodiments, the feedback control method 1400 ( Fig.14 ) or cascade control method 1500 ( Fig.15 ) can be used to control the forming tool 324 ( Figure 3C-3D ) and forming station 204 ( Figure 3C-3D ) in contact time of the glass tube 102 in the glass tube 102. The process variables 1402, 1506 may be responsive to, for example, the temperature of the glass tube 102 measured using the thermal imaging system 120 or a physical property of the glass tube 102 (e.g., the diameter, thickness, or mass of glass per unit length of the glass tube 102), which may be determined by the sizing system 1310 ( Fig.13 ) measured] and the contact time is controlled as a controlled variable 1408, 1512. The contact time of the forming tool 324 and the glass tube 102 can be increased or decreased in response to the process variables 1402, 1506.

[0178] In one or more embodiments, the controlled variable 1408 may be a contact time. When the measured surface temperature reaches the target surface temperature, the controller 1302 may set the contact time to a period starting from when the forming tool 324 first engages the glass tube 102 and ending when the measured surface temperature reaches the target surface temperature. As the main turret 108 aims and moves the glass tube 102 through the forming station 204, the controller 1302 maintains the controlled variable 1408 equal to the contact time determined by the controller 1302 until the thermal imaging system 120 cycles back into position near the forming station 204 to measure the process variable 1402 again. In these embodiments, the contact time may be varied from cycle to cycle, and the effects of long-term sources of surface temperature variability on the contact time may be effectively reduced or eliminated.

[0179] In one or more embodiments, Fig.15The cascade control method 1500 depicted in and previously described in the present disclosure may be adapted to control the contact time of the forming tool 324 with the glass tube 102 based on the surface temperature of the glass tube 102 and the physical properties of the glass tube 102. In these embodiments, the first process variable 1506 may be the surface temperature of the glass tube 102 measured by the thermal imaging system 120. The second process variable 1516 may be the mass of glass per unit length of the glass tube 102 determined by the sizing system 1310. The controlled variable 1512 may be the contact time. Initially, the contact time (controlled variable 1512) is established for one cycle based on comparing the measured surface temperature (first process variable 1506) provided by the thermal imaging system 120 with the target surface temperature (first set point 1508) stored in the control memory module 1306. The contact time may then be further adjusted on a glass tube by glass tube basis based on a comparison between the glass mass per unit area (second process variable 1516) measured by the sizing system 1310 and the target glass mass per unit area (second set point 1518). Implementing the cascade control method 1500 may further allow the control system 1300 to reduce and / or eliminate the effects of short-term sources of variability in glass tube temperature (e.g., variability in the size of the glass tube 102).

[0180] Based on the above, it should now be understood that the embodiments described herein relate to a thermal imaging system 120 and a control system 1300 for use with a converter 100 for producing a plurality of glass articles from a glass tube 102. The thermal imaging system 120 and control system 1300 described herein may be implemented to eliminate or minimize the reliance of existing converters on operator experience and skill in fine-tuning thermal conditions of a glass tube converter 100. The thermal imaging system 120 and converter control system 1300 may minimize the need for experience and shorten the learning curve for new component manufacturers to achieve high quality and consistent production. The thermal imaging system 120 and control system 1300 may also enable faster process adjustments for producing new products or incorporating different glass compositions. The control system 1300 may also enable manufacturers to maximize the yield and production of the converter 100.

[0181] The present disclosure may be implemented in hardware and / or in software (including firmware, resident software, microcode, etc.). The thermal imaging system 120 and / or the control system 1300 may include at least one processor and a computer-readable medium (i.e., a memory module) as previously described in this specification. A computer-usable or computer-readable medium or memory module may be any medium that can contain, store, communicate, propagate, or transport a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0182] The computer usable or computer readable medium or memory module may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared or semiconductor system, apparatus, device or propagation medium. More specific examples of computer readable media (a non-exhaustive list) would include the following: an electrical connection having one or more wires, a portable computer disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), optical fiber, and a portable compact disk read-only memory (CD-ROM). Note that the computer usable or computer readable medium may even be paper or another suitable medium on which the program is printed, since the program may be captured electronically, for example, by scanning the paper or other medium with light, and then compiled, interpreted or otherwise processed in a suitable manner as needed, and then stored in the computer memory.

[0183] Computer program code for implementing the operation of the present disclosure may be written in a high-level programming language (e.g., C or C++) for the sake of development convenience. In addition, computer program code for implementing the operation of the present disclosure may also be written in other programming languages ​​(e.g., but not limited to interpreted languages). Certain modules or routines may be written in assembly language or even microcode to enhance performance and / or memory usage. However, the software implementation of the present disclosure does not rely on implementation with a specific programming language. It will be further understood that the functions of any or all parts of the program modules may also be implemented using discrete hardware components, one or more application specific integrated circuits (ASICs), or programmed digital signal processors or microcontrollers.

[0184] While various embodiments of the thermal imaging system 120 and techniques for using the thermal imaging system 120 to study, start, optimize, and control the glass tube converter 100 have been described herein, it should be understood that each of these embodiments and techniques may be contemplated for use alone or in combination with one or more embodiments and techniques.

[0185] Those skilled in the art will appreciate that various modifications and variations may be made to the embodiments described herein without departing from the spirit and scope of the claimed subject matter. Therefore, it is intended that this specification covers variations and variations of the various embodiments described herein, provided such variations and variations fall within the scope of the appended claims and their equivalents.

Claims

1. A system for producing a glass product from a glass tube, the system comprising: a converter comprising a plurality of processing stations including at least one heating station, at least one forming station, and at least one separation station, wherein the plurality of processing stations are arranged in a loop, wherein the converter displaces a distal end of each of a plurality of glass tubes through the plurality of processing stations; A thermal imaging system, a sizing system, one or more sensors, or a combination thereof; one or more control devices; and A control system, the control system comprising: Control processor; a control memory module communicatively coupled to the control processor; machine-readable and executable instructions stored on said control memory module; one or more inputs communicatively coupled to the thermal imaging system, the sizing system, the one or more sensors, or a combination thereof; as well as one or more outputs communicatively coupled to one or more control devices; The machine-readable and executable instructions, when executed by a control processor, cause the control system to automatically: receiving a process variable from a thermal imaging system, a sizing system, a sensor, or a combination thereof; comparing the process variable to a set point; determining a controlled variable based on the comparison; as well as A control signal representative of a controlled variable is transmitted to the one or more control devices, wherein the control signal causes the one or more control devices to change state to change the operation of the converter.

2. The system of claim 1, wherein the control system is a proportional-integral-derivative controller.

3. The system of claim 1, wherein the machine readable and executable instructions, when executed by the control processor, cause the control system to automatically calculate the controlled variable using one or more proportional, integral, or derivative calculation methods.

4. The system of claim 1 , wherein the machine readable and executable instructions, when executed by the control processor, cause the control system to automatically: determining the set point from a database of historical process variable measurements; The set point is stored in the control memory module.

5. The system of claim 1, wherein the machine readable and executable instructions, when executed by the control processor, cause the control system to automatically and periodically update the set point based on changes observed from the ongoing accumulation of process variable measurements.

6. The system of claim 1, wherein: The process variable is determined at a location downstream of a control device in the one or more control devices; and The machine readable and executable instructions, when executed by the control processor, cause the control system to automatically perform feedback control of the control device based on the process variable value.

7. The system of claim 6, wherein the machine readable and executable instructions, when executed by the control processor, cause the control system to automatically: Measuring process variables; determining the error of the process variable compared to the set point; and The controlled variable is calculated from the error.

8. The system of claim 7, wherein the machine readable and executable instructions, when executed by the control processor, cause the control system to automatically: determining a gain constant; and The error is multiplied by the gain constant to calculate the controlled variable.

9. The system of claim 8, wherein the machine readable and executable instructions, when executed by the control processor, cause the control system to automatically determine the gain constant from the variability of historical operating data of the converter.

10. The system of claim 8, wherein the machine readable and executable instructions, when executed by the control processor, cause the control system to automatically perform one or more bump tests to determine the gain constants.

11. The system of claim 10, wherein the machine readable and executable instructions, when executed by the control processor, cause the control system to automatically: Make small changes in the controlled variables; Measuring the process variable after making small changes in the controlled variable; and The gain is determined from the change in the process variable in response to a change in the controlled variable.

12. The system of claim 1 , wherein the machine readable and executable instructions, when executed by the control processor, cause the control system to automatically determine the controlled variable and transmit a control signal to the one or more control devices for each complete rotation of the main turret of the converter or for every n complete rotations of the main turret of the converter.

13. The system of claim 1, wherein the machine readable and executable instructions, when executed by the control processor, cause the control system to automatically determine the controlled variables on a glass tube by glass tube basis and transmit control signals to the one or more control devices.

14. The system of claim 1, wherein the machine readable and executable instructions, when executed by the control processor, cause the control system to automatically perform cascade control of a control device in the one or more control devices based on a process variable value.

15. The system of claim 14, wherein the machine readable and executable instructions, when executed by the control processor, cause the control system to automatically: measuring a first process variable; transmitting a first process variable to a control system; comparing the first process variable to a first set point associated with the first process variable; determining a first gain constant of the controlled variable based on a response to a change in the first process variable; determining an intermediate controlled variable based on the comparison and a first gain constant; measuring a second process variable; transmitting a second process variable to a control system; comparing the second process variable to a second set point associated with the second process variable; determining a second gain constant for the controlled variable based on a response to a change in the second process variable; and A controlled variable is determined based on the intermediate controlled variable, a comparison of the second process variable with the second set point, and a second gain constant.

16. The system of claim 1, wherein the process variable is one or more of: glass tube outer surface temperature, glass tube inner surface temperature, peak centerline glass temperature of the glass tube, average centerline glass temperature of the glass tube, glass viscosity of the glass tube, temperature distribution of the glass tube as a function of time, temperature gradient across the thickness of the glass tube, size of the glass tube, or a combination thereof.

17. The system of claim 16, wherein the control system is communicatively coupled to the sizing system, and the process variable is a dimension of the glass tube.

18. The system of claim 1, wherein the control system is communicatively coupled to the thermal imaging system, and the process variable is a difference between a first temperature of a glass tube in the plurality of glass tubes and a second temperature of the glass tube.

19. The system of claim 1, wherein the controlled variables include one or more of: positions of one or more fuel control valves, positions of one or more oxygen control valves, positions of one or more air control valves, positions of one or more cooling fluid control valves, aiming movement time of a main turret of a converter, contact time of one or more forming tools with a glass tube of the plurality of glass tubes, or a combination thereof.

20. The system of claim 1, wherein: at least one control device of the one or more control devices operatively coupled to a heating element of the at least one heating station to manipulate heating of each of the plurality of glass tubes by the heating element; and / or The one or more control devices include one or more actuators of the at least one forming station that displace at least one forming tool into removable engagement with each of the plurality of glass tubes.

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