JP2023553100A - Method and system for adjusting slot dies used to produce extruded articles - Google Patents

Abstract

A method of operating a slot die, the slot die comprising: an applicator slot extending along the width of the slot die, the applicator slot being in fluid communication with a fluid flow path through the slot die; a choker bar; and at least one of the group consisting of a flexible die lip. The shape of the choker bar or flexible die lip can be manipulated using a force application mechanism by applying a force generally parallel to the width of the slot die. A method of operating and purging a slot die is further provided in which at least a portion of the applicator slot is blocked by one or more deckles to reduce the effective width of the applicator slot.

Description

TECHNICAL FIELD The present invention relates to slot dies and related assemblies, systems, and methods.

Generally, slot dies include a die lip that forms an applicator slot. The width of the applicator slot can extend along the width of a moving web or the width of a roller that receives an extrudate, such as a film. As used herein, with respect to slot dies and slot die components, "width" refers to the cross-web (or cross-roller) dimension of the slot die and its components. In this regard, the slot die's applicator slot extends along the width of the slot die.

Slot dies are commonly used to form extrudates, coatings, and other extruded articles. As an example, slot dies can be used in slot die coating to apply liquid materials to a moving flexible substrate or "web." There are many variations in slot die coating techniques. As an example, the coating material may be at room temperature or at a controlled temperature. When the coating material temperature is increased to ensure that the coating material is melted or liquefied for processing, this is often referred to as a "hot melt" coating. In other examples, the coating material can include a solvent diluent. The solvent may be water, an organic solvent, or any suitable fluid that dissolves or disperses the components of the coating. The solvent is typically removed in subsequent processing, such as by drying. The coating can include single or multiple layers, and several slot dies can be used to apply multiple layers simultaneously. The coating may be a continuous coating across the width of the die, or alternatively may be composed of strips, each strip extending over only a portion of the width of the die and separated from adjacent strips.

Slot dies are also used to form extrudates, including thin film extrudates or other extrudates. In some examples, the extrudate may be an extrusion coating and may be applied to a web substrate, a process sometimes referred to as extrusion coating. In other examples, the extruded material directly forms a film or web. The extruded film may then be processed by length stretching or tentering operations. Like coatings, extrudates may include a single layer or multiple layers.

The thickness of the extrudate, such as a film or coating, depends, among other factors, on the flow rate of the extrudate through the slot die. In one example, the slot die includes an adjustable choker bar within the flow path that can be used to locally adjust the flow rate of the extrudate through the slot die to provide a desired choker bar height profile. can be included in The slot die also adjusts the local height of the applicator slot (i.e., slot height) to control the flow rate of extrudate from the applicator slot to provide the desired extrudate thickness profile. It can include a flexible die lip that can be used for.

The slot die may include a plurality of actuators spaced along the width of the applicator slot to manipulate the thickness profile. For example, each actuator can be configured to provide localized positional adjustment of a choker bar or flexible die lip.

After starting the extrusion process using a slot die, the cross-web profile of the extrudate can be measured. Each actuator may then need to be individually adjusted to provide the desired thickness profile, such as a uniform thickness of the extrudate across the width of the applicator slot.

The present disclosure includes techniques for manipulating the shape of a die lip or choker bar by applying a force generally parallel to the width of the die, and the associated force application mechanism includes a flexible die lip or restrictor/choker bar. Most of it is contained within. Such a force parallel to the width of the die can be provided by expansion or contraction in all directions, such as caused by localized heating or cooling of the die lip or choker bar. For example, the flatness of the die lip can be manipulated by expanding the metal near the die lip, thereby changing the shape of the die lip between discrete control points. This technique is similar to a die with muscles that can be flexed between positioning devices.

These techniques can be used in combination with conventional adjuster means to advantageously adjust the die slot between conventional die slot control element positions themselves, thus improving the spatial resolution of extrusion uniformity control. can do.

In a first aspect, a method of operating a slot die is disclosed. The slot die includes one of the group consisting of an applicator slot extending along the width of the slot die and in fluid communication with a fluid flow path through the slot die, a choker bar, and a flexible die lip. at least one. The method includes manipulating the shape of the choker bar or flexible die lip by applying a force generally parallel to the width of the die using a force application mechanism.

In a second aspect, a method is provided for operating a slot die, the slot die having an applicator slot extending along the width of the slot die, the applicator slot being in fluid communication with a fluid flow path through the slot die. a slot, at least one of the group consisting of a choker bar and a flexible die lip, and a plurality of actuators spaced apart along the width of the slot die, each actuator of the plurality of actuators directing fluid through the applicator slot. a plurality of actuators operable to adjust the height of the fluid flow path at a respective position of each actuator to provide localized adjustment of the flow; A crossweb where a choker bar or flexible die lip of a slot die is locally expanded or contracted along a direction generally parallel to the width, thereby causing a force application mechanism to engage the choker bar or flexible die lip. The method includes determining settings for a force application mechanism and engaging the force application mechanism with a choker bar or flexible die lip based on the determined settings to adjust a slot height profile.

In a third aspect, a method of operating a slot die is provided, the slot die having an applicator slot extending along the width of the slot die, the applicator slot being in fluid communication with a fluid flow path through the slot die. a slot, at least one of the group consisting of a choker bar and a flexible die lip, and a plurality of actuators spaced apart along the width of the slot die, each actuator of the plurality of actuators directing fluid through the applicator slot. a plurality of actuators operable to adjust the height of the fluid flow path at a respective position of each actuator to provide local adjustment of the flow; blocking a portion of the applicator slot to reduce the effective width of the applicator slot; and using a controller to block a portion of the applicator slot to reduce the effective width of the applicator slot; predicting a set of individualizations from the configuration, the prediction being based on a known correlation between the set of individualizations and a cross-web slot height profile of the extrudate; configuring the position of each actuator according to a set of individual settings predicted for adjustment of the die, and the actuator is fixed over the blocked zone of the applicator slot during operation of the slot die. and is dynamic over the unobstructed zone of the applicator slot.

In a fourth aspect, a method of manufacturing an extruded article comprising operating a slot die according to the method described above and extruding an extrudate through an applicator slot of the slot die to obtain an extruded article. , a method is provided.

In a fifth aspect, a method of purging a slot die is provided, the slot die having an applicator slot extending along the width of the slot die, the applicator slot being in fluid communication with a fluid flow path through the slot die. a slot, a choker bar or flexible die lip extending along the width of the slot die, and a plurality of actuators spaced apart along the choker bar or flexible die lip, each actuator controlling fluid flow through the applicator slot. a plurality of actuators operable to adjust the height of the applicator slot at their respective locations to provide localized adjustment, and a plurality of actuators operable to adjust the height of the applicator slot by blocking a portion of the applicator slot; one or more deckles to reduce the width, the method includes manipulating the shape of the choker bar or flexible die lip by applying a force using a plurality of actuators to reduce the width of the target cross-web slot height. Obtaining a profile, wherein the actuator is fixed above the blocked zone of the applicator slot and dynamic above the unblocked zone of the applicator slot; Cross-web slot height along the unobstructed zone of the applicator slot using multiple actuators, with a progressively decreasing degree of expansion along the transition zone between the unobstructed and blocked zones. selectively enlarging the profile.

In a sixth aspect, a system is provided, the system comprising a slot die, an applicator slot extending along the width of the slot die, and an applicator slot in fluid communication with a fluid flow path through the slot die. a slot die including a slot, at least one of the group consisting of a choker bar and a flexible die lip, and a force application mechanism operably coupled to the choker bar or the flexible die lip; a controller configured to position each actuator and operate the slot die according to one of the actuators, the controller applying a force generally parallel to the width of the slot die using a force application mechanism; The choker bar or flexible die lip is configured to manipulate the shape of the choker bar or flexible die lip.

In a seventh aspect, a system is provided that includes a slot die and a controller. The slot die includes an applicator slot extending along the width of the slot die, the applicator slot being in fluid communication with a fluid flow path through the slot die, and a choker bar or flexible member extending along the width of the slot die. a flexible die lip and a choker bar or a plurality of actuators spaced apart along the flexible die lip, each actuator at its respective location to provide localized adjustment of fluid flow through the applicator slot; a plurality of actuators operable to adjust the height of the applicator slot; and one or more deckles that block a portion of the applicator slot to reduce the effective width of the applicator slot. The controller manipulates the shape of the choker bar or flexible die lip by applying a force using a plurality of actuators to obtain a target cross-web slot height profile, where the actuators are used to block the applicator slot. fixed above the blocked zone and dynamic above the unblocked zone of the applicator slot, and the extent of expansion along the transition zone between the unblocked and blocked zones. The cross-web slot height profile is configured to selectively expand the cross-web slot height profile along an unobstructed zone of the applicator slot using the plurality of actuators while gradually decreasing the cross-web slot height profile.

The details of one or more implementations of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the specification and drawings, and from the claims.

Repeat use of reference characters in the specification and drawings is intended to represent the same or similar features or elements of the disclosure. It should be understood that many other modifications and embodiments may be devised by those skilled in the art and are within the scope and spirit of the principles of this disclosure. Illustrations may not be drawn to scale.
FIG. 12 illustrates a slot die including a choker bar having multiple actuators, each actuator being operable to adjust the height of a fluid flow path at its location. FIG. 12 illustrates a slot die including a choker bar having multiple actuators, each actuator being operable to adjust the height of a fluid flow path at its location. A slot die including an adjustable rotating rod having a plurality of actuators connected to the rotating rod, each actuator adjusting the local position of the rotating rod at its location, thereby adjusting the local height of the applicator slot. FIG. 3 illustrates a slot die operable to adjust. A slot die including a flexible die lip having a plurality of actuators connected to the flexible die lip, each actuator adjusting the local position of the flexible die lip at its location, thereby adjusting the local position of the applicator slot. FIG. 3 shows a slot die operable to adjust the height. FIG. 3 illustrates an actuator assembly including a position sensor and a controller for selecting a position of the actuator assembly based on the output of the position sensor. 2 is a flowchart illustrating a technique for selecting the position of each actuator of a plurality of actuators of a slot die according to a preselected cross-web profile of an extrudate. 2 is a flowchart illustrating a technique for selecting the position of each actuator of a plurality of actuators of a slot die according to a preselected die cavity pressure during operation of the die. 2 is a flowchart illustrating a technique for purging a slot die by increasing the height of the fluid flow path adjacent each of the actuators while continuing to operate the die. 2 is a flowchart illustrating a technique for purging a slot die by substantially closing the fluid flow path adjacent each of the actuators while continuing to operate the die. FIG. 3 shows a strip coating containing a pattern generated by iteratively adjusting the actuator position settings of a slot die. FIG. 3 shows an extrudate containing a pattern produced by iteratively adjusting the actuator position settings of a slot die. FIG. 2 is a diagram illustrating an example of a user interface for a slot die controller. FIG. 2 is a diagram illustrating an example of a user interface for a slot die controller. FIG. 2 is a diagram illustrating an example of a user interface for a slot die controller. FIG. 2 is a diagram illustrating an example of a user interface for a slot die controller. FIG. 3 is a diagram illustrating a technique for retrofitting a set of actuator assemblies to a slot die. FIG. 4 is a diagram of a technique for manipulating die lip shape by applying a force generally parallel to the width of a die, where the force application mechanism is a flexible die lip or a restrictor/choker, in accordance with the techniques disclosed herein; Most will be housed inside the bar. FIG. 4 is a diagram of a technique for manipulating die lip shape by applying a force generally parallel to the width of a die, where the force application mechanism is a flexible die lip or a restrictor/choker, in accordance with the techniques disclosed herein; Most will be housed inside the bar. FIG. 4 is a diagram of a technique for manipulating die lip shape by applying a force generally parallel to the width of a die, where the force application mechanism is a flexible die lip or a restrictor/choker, in accordance with the techniques disclosed herein; Most will be housed inside the bar. FIG. 4 is a diagram of a technique for manipulating die lip shape by applying a force generally parallel to the width of a die, where the force application mechanism is a flexible die lip or a restrictor/choker, in accordance with the techniques disclosed herein; Most will be housed inside the bar. FIG. 4 is a diagram of a technique for manipulating die lip shape by applying a force generally parallel to the width of a die, where the force application mechanism is a flexible die lip or a restrictor/choker, in accordance with the techniques disclosed herein; Most will be housed inside the bar. FIG. 4 is a diagram of a technique for manipulating die lip shape by applying a force generally parallel to the width of a die, where the force application mechanism is a flexible die lip or a restrictor/choker, in accordance with the techniques disclosed herein; Most will be housed inside the bar. FIG. 4 is a diagram of a technique for manipulating die lip shape by applying a force generally parallel to the width of a die, where the force application mechanism is a flexible die lip or a restrictor/choker, in accordance with the techniques disclosed herein; Most will be housed inside the bar. FIG. 4 is a diagram of a technique for manipulating die lip shape by applying a force generally parallel to the width of a die, where the force application mechanism is a flexible die lip or a restrictor/choker, in accordance with the techniques disclosed herein; Most will be housed inside the bar. FIG. 4 is a diagram of a technique for manipulating die lip shape by applying a force generally parallel to the width of a die, where the force application mechanism is a flexible die lip or a restrictor/choker, in accordance with the techniques disclosed herein; Most will be housed inside the bar. FIG. 4 is a diagram of a technique for manipulating die lip shape by applying a force generally parallel to the width of a die, where the force application mechanism is a flexible die lip or a restrictor/choker, in accordance with the techniques disclosed herein; Most will be housed inside the bar.

As used herein, the terms "preferred" and "preferably" refer to embodiments described herein that can provide certain advantages under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments is not intended to imply that other embodiments are not useful or to exclude other embodiments from the scope of the invention.

As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to an element with "a" or "the" may include one or more of the elements and their equivalents known to those skilled in the art. Additionally, the term "and/or" means one or all of the listed elements, or a combination of any two or more of the listed elements.

It is noted that the term "comprising" and variations thereof do not have a limiting meaning when these terms appear in the accompanying description. Still further, "a," "an," "the," "at least one," and "one or more" are used interchangeably herein. Relative terms such as left, right, front, rear, top, bottom, side, above, below, horizontal, vertical, etc. may be used herein, from the perspective as seen in a particular drawing. It is something. However, these terms are only used for ease of description and are not intended to limit the scope of the invention in any way.

Throughout this specification, references to "one embodiment," "a particular embodiment," "one or more embodiments," or "an embodiment" refer to specific features, structures, structures, etc. described with respect to that embodiment. A material or property is meant to be included in at least one embodiment of the invention. Thus, the occurrences of phrases such as "in one or more embodiments," "in a particular embodiment," "in one embodiment," or "in an embodiment" in various places throughout this specification are not necessarily They are not referring to the same embodiment of the invention. Where applicable, product names should be written in all capital letters.

1A and 1B show a slot die 10. FIG. The slot die 10 includes an upper die block 2 and a lower die block 3. The upper die block 2, in combination with the lower die block 3, forms a fluid flow path through the slot die 10. The fluid flow path includes an inlet 5, a die cavity 4, and an applicator slot 6. The applicator slot 6 is between the rotating rod 12 attached to the upper die block 2 and the die lip 13 of the lower die block 3. Because slot die 10 includes a rotating rod 12 in its applicator slot, slot die 10 is sometimes referred to as a rotating rod die.

Slot die 10 includes a choker bar 11 that extends across the width of the fluid flow path within slot die 10 . As an example, the width of the fluid flow path within the slot die 10 at the choker bar 11 may be approximately the same as the width of the applicator slot 6 such that the choker bar 11 extends along the width of the applicator slot 6. . Actuator assemblies 200 are mounted on a common mounting bracket 9 and spaced apart along the width of slot die 10. In some examples, mounting bracket 9 may be segmented, eg, mounting bracket 9 may include a separate structure for each actuator assembly 200. Each actuator assembly 200 changes the height of the fluid flow path at its respective location along the width of the slot die 10 by changing the position of the choker bar 11 within the fluid flow path of the extrudate within the slot die 10. is operable to adjust and provide localized adjustment of fluid flow through the applicator slot 6.

During operation of the slot die 10, extrudate enters the slot die 10 at the fluid flow path inlet 5 and travels through the die cavity 4 until the extrudate exits through the applicator slot 6 and is applied to the moving rollers 7. continues through the fluid flow path of the slot die 10 containing the fluid. In some examples, the extrudate may be applied to a moving web (not shown), and in other examples, the extrudate may be applied directly to roller 7. The extrudate and web (if applicable) can be run over a series of rollers to cool the extrudate. One or more additional processes may be performed on the extrudate downstream of roller 7. Although not germane to this disclosure, such processes include, but are not limited to, stretching, coating, texturing, printing, cutting, rolling, and lamination. In some processes, the manufactured release liner can be removed and a release liner added, or one or more additional layers (such as a laminated transfer tape) can be added. Curing steps such as exposure to an electron beam, oven, or ultraviolet (UV) chamber can also be performed.

As shown in FIG. 1B, slot die 10 includes a set of actuator assemblies 200 mounted on a common mounting bracket 9. As shown in FIG. Although five actuator assemblies 200 are shown, different numbers of actuator assemblies are also possible. Each actuator assembly 200 is attached to or otherwise engaged to choker bar 11 , and the actuator assemblies 200 are spaced apart along the width of choker bar 11 . Each of the actuators is operable to provide local adjustment of the position of the choker bar 11 within the fluid flow path within the slot die 10, thereby controlling the height of the fluid flow path at that location.

As described in further detail with respect to FIG. 4, each of the actuator assemblies 200 can include a motor that drives a linear actuator. Each of the actuator assemblies 200 may also include precision sensors, such as linear variable differential transformers (LVDTs) or linear encoders, that detect positional movement of the linear actuator output shaft. The output shafts of the linear actuator assemblies 200 are spaced apart along the width of the choker bar 11 such that each linear actuator assembly 200 is operable to adjust the local position of the choker bar. As explained in more detail below, the position of each linear actuator is individually selectable to provide the desired cross-web profile of the extrudate. Additionally, the position of the linear actuator assembly 200 can be adjusted to position the desired die within the die cavity 4 during operation of the slot die 10 by adjusting the overall cross-sectional area of the fluid flow path adjacent the choker bar 11 within the slot die 10. Can be precisely adjusted to provide cavity pressure. In other examples, the position of each actuator assembly 200 may be actively controlled to produce an extrudate with patterned features, such as repeating or random patterned features. As referred to herein, references to the position of the actuator or actuator assembly are intended to refer more specifically to the relative positioning of the actuator output shafts.

FIG. 2 shows a slot die 20. FIG. Slot die 20 includes an adjustable rotating rod 22 having a plurality of actuator assemblies 200 connected thereto. Each actuator assembly 200 is operable to adjust the local position of the rotating rod 22 at its location, thereby adjusting the local height of the applicator slot 6. Some aspects of slot die 20 are similar to aspects of slot die 10, and will be described in limited detail with respect to slot die 20. Components of slot die 20 having the same reference numbers as components of slot die 10 are substantially similar to similarly numbered components of slot die 10.

The slot die 20 includes an upper die block 2 and a lower die block 3. The upper die block 2, in combination with the lower die block 3, forms a fluid flow path through the slot die 20. The fluid flow path includes an inlet 5, a die cavity 4, and an applicator slot 6. The applicator slot 6 is located between the adjustable rotating rod 22 mounted on the upper die block 2 and the die lip 13 of the lower die block 3. Because slot die 20 includes an adjustable rotating rod 22 in its applicator slot, slot die 20 is sometimes referred to as a rotating rod die.

Slot die 20 differs from slot die 10 in that the height of applicator slot 6 is controlled by an actuator assembly 200 that connects to rotating rod 22. Actuator assemblies 200 are mounted on a common mounting bracket 9 and spaced apart along the width of slot die 20. Each actuator assembly 200 adjusts the height of the fluid flow path at its respective location along the width of the slot die 20 by changing the position of the rotating rod 22 to improve fluid flow through the applicator slot 6. Operable to provide local adjustments. Although only one actuator assembly 200 is shown in FIG. 2, the slot die 20 has actuator assemblies 200 spaced apart along the width of the rotating rod 22 and the slot die 20, similar to the arrangement of the actuator assembly 200 shown in FIG. 1B. Contains a set of

During operation of the slot die 20, extrudate enters the slot die 20 at the fluid flow path inlet 5 containing the die cavity 4 until the extrudate is applied to the moving rollers 7 exiting through the applicator slot 6. Continue through the fluid flow path of slot die 20. In some examples, the extrudate may be applied to a moving web (not shown), and in other examples, the extrudate may be applied directly to roller 7. The extrudate and web (if applicable) can be run over a series of rollers to cool the extrudate. One or more additional processes may be performed on the extrudate downstream of roller 7, as described above with respect to FIGS. 1A and 1B.

Each of the actuator assemblies 200 is operable to control the height of the fluid flow path at that location by providing local adjustment of the position of the rotating rod 22. As described in more detail below, the position of each actuator assembly 200 is individually selectable to provide the desired cross-web profile of the extrudate. Additionally, the position of the linear actuator assembly 200 can be precisely adjusted to provide the desired die cavity pressure within the die cavity 4 during operation of the slot die 20 by adjusting the overall cross-sectional area of the applicator slot 6. can do. In other examples, the position of each actuator assembly 200 may be actively controlled to produce an extrudate with patterned features, such as repeating or random patterned features.

Although slot die 20 does not include a choker bar, in other embodiments, a slot die with an adjustable rotating rod may also include an adjustable choker bar, such as choker bar 11 of slot die 10. The position of such a choker bar, similar to the choker bar 11 of the slot die 10, can be locally controlled by a set of actuators.

FIG. 3 shows a slot die 30. As shown in FIG. Slot die 30 includes a flexible die lip 32 having a plurality of actuator assemblies 200 connected thereto. Each actuator assembly 200 is operable to adjust the local position of the flexible die lip 32 at its location, thereby adjusting the local height of the applicator slot 6. Some aspects of slot die 30 are similar to aspects of slot die 10 and slot die 20, and will be described in limited detail with respect to slot die 30. Components of slot die 30 having the same reference numbers as components of slot die 10 and slot die 20 are substantially similar to similarly numbered components of slot die 10 and slot die 20.

The slot die 30 includes an upper die block 2 and a lower die block 3. The upper die block 2, in combination with the lower die block 3, forms a fluid flow path through the slot die 30. The fluid flow path includes an inlet 5, a die cavity 4, and an applicator slot 6. The applicator slot 6 is between a die lip 34 that is part of the upper die block 2 and a flexible die lip 32 of the lower die block 3.

Slot die 30 differs from slot die 10 in that the height of applicator slot 6 is controlled by an actuator assembly 200 that connects to flexible die lip 32. Actuator assemblies 200 are mounted on a common mounting bracket 9 and spaced apart along the width of slot die 30. Each actuator assembly 200 adjusts the height of the fluid flow path at its respective location along the width of the slot die 30 by changing the position of the flexible die lip 32 to increase fluid flow through the applicator slot 6. Operable to provide local regulation of flow. Although only one actuator 220 is shown in FIG. 3, the slot die 30 has a flexible die lip 32 and an actuator assembly spaced apart along the width of the slot die 30, similar to the arrangement of the actuator assembly 200 shown in FIG. 1B. Contains 200 sets.

During operation of the slot die 30, extrudate enters the slot die 30 under pressure at the fluid flow path inlet 5 and continues through the die until the extrudate exits through the applicator slot 6 and is applied to the moving roller 7. Continue through the fluid flow path of slot die 30 including cavity 4 . In some examples, the extrudate may be applied to a moving web (not shown), and in other examples, the extrudate may be applied directly to roller 7. The extrudate and web (if applicable) can be run over a series of rollers to cool the extrudate.

In other embodiments, slot die 30 may be used with different configurations of rollers. For example, the extrudate can form a curtain that falls onto a downstream roller (in this case called a casting wheel) that can be temperature controlled. In other examples, the extrudate curtain may fall vertically into the nip of two rollers for subsequent processing, or may traverse horizontally (or at any angle). It is often used in both film extrusion and extrusion coating operations.

One or more additional processes may be performed on the extrudate downstream of roller 7, as described above with respect to FIGS. 1A and 1B.

Each of the actuator assemblies 200 is operable to provide local adjustment of the position of the flexible die lip 32 to thereby control the height of the fluid flow path at that location. As described in more detail below, the position of each actuator assembly 200 is individually selectable to provide the desired cross-web profile of the extrudate. Additionally, the position of the linear actuator assembly 200 can be precisely adjusted to provide the desired die cavity pressure within the die cavity 4 during operation of the slot die 30 by adjusting the overall cross-sectional area of the applicator slot 6. can do. In other examples, the position of each actuator assembly 200 may be actively controlled to produce an extrudate with patterned features, such as repeating or random patterned features.

Although slot die 30 does not include a choker bar, in other embodiments, a slot die with a flexible die lip may also include an adjustable choker bar, such as choker bar 11 of slot die 10. The position of such a choker bar, similar to the choker bar 11 of the slot die 10, can be locally controlled by a set of actuators.

FIG. 4 shows an assembly that includes an actuator assembly 200, a zero backlash coupler 240, and a controller 300. As shown in FIGS. 1A-3, the actuator assembly 200 can be configured, for example, by adjusting the height of the applicator slot, similar to the slot dies 20, 30, or by adjusting the fluid flow within the slot die, similar to the slot die 10. It may be used in slot dies to provide localized adjustment of fluid flow paths in the slot die by adjusting the height of the channels.

Actuator assembly 200 includes a motor 210, a linear actuator 220 coupled to motor 210, and a position sensor 230. As an example, motor 210 may be a stepping motor. An output shaft (not shown) of motor 210 is mechanically coupled to linear actuator 220. Sensor 230 senses the position of linear actuator 220. For example, sensor 230 may be an LVDT sensor or a linear encoder. The sensor 230 is secured to the output shaft 222 of the linear actuator 220 by a clamp 232 and accurately measures the relative position of the output shaft 222 of the linear actuator 220. In other examples, sensor 230 may measure output coupler 240, die actuator linkage 252, flexible die lip 32, rotating rod 22, or choker bar 11. As an example, an actuator assembly suitable for use as actuator assembly 200 is available from Honeywell International Incorporated (Morristown, New Jersey).

Controller 300 receives position input from both motor 210 and sensor 230. For example, motor 210 may be a stepper motor and may provide an indication of the number of "steps" taken by the stepper motor from a known reference position of the stepper motor. Sensor 230 may provide more accurate position information to controller 300 than that provided by motor 210. Controller 300 provides commands to motor 210 to drive output shaft 222 of actuator 220 to a preselected position. For example, controller 300 may monitor the position of output shaft 222 of actuator 220 using sensor 230 while operating motor 210 to position output shaft 222 of actuator 220 according to a preselected position. . In some examples, controller 300 can control a set of actuator assemblies 200 either simultaneously or sequentially. For example, the controller 300 can control each of the actuator assemblies 200 of the slot die 10, as shown in FIG. 1B.

In slot dies 10, 20, 30, the output shaft 222 of actuator 220 may advantageously be connected to die actuator linkage 252 by a zero backlash coupler 240. Zero backlash coupler 240 includes two halves, a lower half 242 and an upper half 244, that are screwed together in this example. Lower half 242 is attached directly to die actuator linkage 252 with screws. Additionally, zero backlash coupler 240 includes a laminated protrusion assembly that is bolted to the end of output shaft 222 of actuator 220. The stacked protrusion assembly includes two metal discs 246 surrounding an insulating disc 248. As one example, insulating disk 248 may include a ceramic material. Lower half 242 and upper half 244 combine to enclose a laminated protrusion assembly that includes a metal disk 246 and an insulating disk 248 bolted to the end of output shaft 222 of actuator 220 . When upper half 244 is securely screwed to lower half 242, output shaft 222 of actuator 220 is effectively connected to zero backlash coupler 240 and die actuator linkage 252.

Zero backlash coupler 240 functions to thermally isolate actuator assembly 200 from the slot die. Specifically, insulating disk 248 significantly limits the metal-to-metal contact path between output shaft 222 of actuator 220 and die actuator linkage 252. This helps protect actuator assembly 200 from damaging heat of the slot die. For example, slot dies typically operate at temperatures in excess of 300°F (149°C). In contrast, components of actuator assembly 200, including motor 210 and sensor 230, can experience limited functionality or even permanent damage when exposed to temperatures above 130°F (54°C). There is sex. Thus, zero backlash coupler 240 can function to maintain the temperature of actuator assembly 200 below 130 degrees Fahrenheit (54 degrees Celsius). In some examples, metal disk 246 can also be formed from a non-metallic material so that there is no metal-to-metal contact between output shaft 222 of actuator 220 and die actuator linkage 252. Such embodiments further thermally isolate actuator assembly 200 from the slot die housing. In a further example, the surface area of coupler 240 can be selected to dissipate heat to maintain the temperature of actuator assembly 200 below 130 degrees Fahrenheit (54 degrees Celsius). This can be used independently or in combination with insulating disc 248. In further examples, active thermal control can be used to cool the zero backlash coupler 240, output shaft 222, or actuator assembly 200. Suitable examples of active thermal control include convective airflow, circulating liquid, and thermionic devices.

In contrast to slot die designs that utilize differential bolts as the actuation mechanism, zero backlash coupler 240 connects output shaft 222 of actuator 220 to die actuator linkage 252 with limited or no backlash. join to. Differential bolt mechanisms can have backlash in excess of 100 micrometers, whereas zero backlash couplers 240 have a backlash of less than 10 micrometers, or even less than 5 micrometers, such as about 3 micrometers. Can provide no backlash.

In slot dies that utilize a set of differential bolts to control applicator slot width or choker bar position, the relatively large backlash of each differential bolt can be reduced by adjusting the position of one differential bolt. , meaning there is a possibility to change the height of the fluid flow path in other bolts. Therefore, the absolute position of the choker bar cannot be known during operation of the extrusion die. In contrast, for slot dies 10, 20, 30, the position of the output shaft 222 of the actuator 220 is limited to the choker bar 11 (for slot die 10), the rotating rod 22 (for slot die 20), and the flexible die lip. 32 (in case of slot die 30). As such, slot dies 10, 20, and 30 facilitate repeatable, precise positioning that is not available with slot dies that utilize differential bolts as an actuation mechanism.

FIG. 5 is a flowchart illustrating a technique for selecting the position of each actuator of a plurality of actuators of a slot die according to a preselected cross-web profile of the extrudate. Although not limited to the slot dies disclosed herein, for clarity, the technique of FIG. 4) will be explained. In different embodiments, the technique of Figure 5 can be applied to strip coating, film slot die, multilayer slot die, hot melt extrusion coating die, drop die, rotating rod die, adhesive slot die, solvent coating slot die, aqueous coating die, slot feeding. It can be utilized in knife dies, extrusion replication dies, vacuum contact dies, or other slot dies.

First, a slot die such as slot die 10 is prepared (step 502). The slot die includes an applicator slot extending along the width of the slot die and a plurality of actuators spaced apart along the width of the slot die. The applicator slot is in fluid communication with a fluid flow path through the slot die. Each actuator of the plurality of actuators is operable to adjust the height of the fluid flow path at its respective location to provide localized adjustment of fluid flow through the applicator slot.

Next, a controller, such as controller 300, is provided that communicates with each actuator (step 504). The controller is configured to set the position of each actuator according to one of a plurality of individual settings, such as a measured position of sensor 230 and/or a stepper motor setting for motor 210.

Using fluid dynamics and a digital model of slot die 10, such as a solid model of slot die 10, controller 300 predicts a set of individual settings from a plurality of individual settings corresponding to a preselected cross-web profile. (step 506). In different embodiments, controller 300 may retrieve the preselected cross-web profile from a non-transitory computer-readable medium or receive the preselected cross-web profile from user input.

In different embodiments, the predicted settings may correspond to measurements from sensors 230 and/or individual position settings of motor 210. Sensor 230 may provide more accurate position information to controller 300 than that provided by motor 210. Thus, the controller 300 can predict the settings of the actuator assembly 200 based on measurements from the sensor 230, and instead of directly driving the motor 210 up to a number of steps corresponding to the predicted position. The motor 210 can be operated to position the output shaft 222 according to the set settings.

In a slot die that includes multiple actuator assemblies, such as actuator assembly 200, each actuator assembly includes a measurement device, such as sensor 230, and each measurement device is configured to provide a local measurement of the slot die; The local measurements correspond to the height of the fluid flow path at the location of the respective measurement device. As a controller, such as controller 300, positions each of the actuators, eg, according to a set of personalized settings, the controller can monitor local measurements from the measurement equipment. The controller then adjusts, for each of the actuators, the relative positions of the actuators until the actuators provide an absolute height of the fluid flow path at each position of the actuator defined by the set of individual settings. good.

The fluid dynamics, extrudate fluid properties, and digital model of the die allow the controller 300 to predict individual settings of the actuators of the slot die 10. In many applications, it is desirable to provide a consistent thickness of extrudate across the width of the die. As another example of strip coating, the controller can predict the individual settings of the actuator of the slot die 10 to predict a set of individual settings from a plurality of individual settings that correspond to a preselected strip width. .

Modeling the extrudate flowing through the die is the applicator slot width, the distance from the manifold cavity to the outlet of the applicator slot, and the narrow dimension of the applicator slot between the two parallel surfaces that define the slot itself. Many aspects of the die itself can be incorporated, including slot height. One fundamental issue in achieving flow uniformity and critical uniformity of coated products is the ability to construct dies with the best possible uniformity of die slot height. The sensitivity is greater than linear, meaning that the variation in slot height is magnified in the extrudate.

Flow modeling may use any suitable model characterizing fluid rheology. For example, flow modeling may include finite element analysis or may rely more directly on one or more equations. As an example, for a power law fluid, the relationship between the flow in the slot and the slot geometry is given by:

In Equation 1, Q/W is the flow rate per unit width, B is the slot height, P is the pressure, L is the slot length (corresponding to the die width), and n is the power law exponent and K is the power law viscosity coefficient. A Newtonian constant viscosity fluid has n=1, then K is the numerical viscosity.

As another example, slot uniformity can be characterized by the uniformity of the walls of the slot. If each slot has a total nominal runout of 2t, the percent uniformity of flow from the slot is:

For constant viscosity (Newtonian) fluids, this means that the coating uniformity is the cube of the slot height (B). This relationship is shown in Equation 3.

Equation 3 may not be used directly to predict slot settings because it may not take into account all details, including details related to extrusion flow, materials, and die design itself. However, Equation 3 shows the importance of providing precisely adjusted height across the width of the die. Specifically, Equation 3 shows that any variation in fluid flow path height will be magnified in the cross-web profile of the resulting extrudate.

Equation 1 may be used, for example, to predict die slot variation because, according to the techniques disclosed herein, the position of the actuator, and by inference the slot height B, The extrudate target thickness is known in combination with the currently measured extrudate thickness. Previously, it was not possible to know the absolute position of the slot height during the extrusion process, for example due to the backlash of the differential bolt. Using a known target extrudate thickness and a measured extrudate thickness profile, Equation 1 can predict the appropriate die slot variation. For example, since we know by inference the relationship between the slot height profile and the extrudate thickness profile from a known slot height profile and a measured extrudate thickness profile, we therefore obtain the target thickness profile of the slot The height profile can be predicted.

Assuming that other elements of the flow path are of minor importance, for Newtonian fluids, the predicted slot height B'i corresponding to actuator "i" is calculated as shown in Equation 4.

For a more generalized power law fluid, Equation 4 can be expressed as Equation 5.

To illustrate, fluid mechanical predictions can include die geometry. For flexible die lips, such as flexible die lip 32 of FIG. 3, the slot height can be better approximated by considering convergent or diverging slots with a nominally fixed slot at the hinge point. Assuming that the hinge point slot remains constant, Equation 6 can be applied.

According to the hydrodynamic lubrication approximation, it is as follows.

This gives Equation 8. Equation 9 represents ci in Equation 8.

While these closed-form examples are useful, it is clear that the model can be extended to include all possible details of mechanical, thermal, and hydrodynamic process details. The better the predictive model, the faster the techniques disclosed herein will converge toward the best operating conditions for the desired extrudate profile.

Equations 1-9 are merely exemplary; any number of equations may be used to predict the settings of actuator assembly 200 of slot die 10 corresponding to a preselected cross-web profile. For example, predicting the optimal settings for the actuator assembly 200 of the slot die 10 may include modeling heat transfer and heat dissipation throughout the slot die 10 and the extrudate. Such predictive modeling may include predictions of mechanical deflections of die assemblies and mechanical elements due to heat and flow induced forces. As previously discussed, such models may rely on finite element analysis or use more general equations to determine the size of the actuator assembly 200 of the slot die 10 corresponding to a preselected cross-web profile. The settings may be predicted.

Once the controller 300 predicts the settings of the actuator assembly 200 of the slot die 10 that correspond to the preselected cross-web profile, the slot die 10 will move the extrudate with the actuator assembly 200 positioned according to the predicted set of settings. through the fluid flow path and out of the applicator slot 6 (step 508).

During operation of slot die 10, the controller evaluates the cross-web profile of the extrudate after it exits the applicator slot according to measurements of the extrudate (step 510). For example, controller 300 may receive input from a sensor that directly measures extrudate thickness at multiple cross-web locations. As an example, a beta thickness gauge can be used to measure the thickness of an extrudate during operation of a slot die. In the case of strip coating, controller 300 can receive input from sensors that directly measure the strip width and/or thickness of individual strips. Using the cross-web profile evaluation, fluid dynamics, and digital model of the die, the controller 300 then makes adjustments to the predicted set of individual settings to pre-select after the extrudate exits the applicator slot. Determine whether it is possible to provide a cross-web profile of the extrudate that more closely matches the cross-web profile obtained.

Controller 300 allows adjustments to the set of predicted individual settings to provide a cross-web profile of the extrudate that more closely matches the preselected cross-web profile after the extrudate exits the applicator slot. If so, the controller predicts an improved set of personalizations from the plurality of personalizations corresponding to the preselected cross-web profile (step 512). While continuing to operate the slot die by passing extrudate through the fluid flow path and out of the applicator slot, controller 300 repositions the actuator according to the improved set of predicted individualization settings (step 514). Steps 510, 512, and 514 may be repeated until the controller 300 determines that the set of predicted settings cannot be improved and/or at periodic intervals to maintain the desired cross-web profile. can. The set of personalized settings (step 514) is for future retrievals where similar materials, extrusion or coating properties, and processing conditions are required, and for future use minutes, hours, or years later. Can be saved as a recipe.

FIG. 6 is a flowchart illustrating a technique for selecting the position of each actuator of a plurality of actuators of a slot die according to a preselected die cavity pressure. Although not limited to the slot dies disclosed herein, for the sake of clarity, the technique of FIG. 4) will be explained. In different embodiments, the technique of Figure 6 can be applied to a film slot die, a multilayer slot die, a hot melt extrusion coating die, a drop die, a rotating rod die, an adhesive slot die, a solvent coating slot die, an aqueous coating die, a slot-fed knife die, an extrusion It can be used for replication dies, vacuum contact dies, or other slot dies.

First, a slot die such as slot die 10 is prepared (step 602). The slot die includes an applicator slot extending along the width of the slot die and a plurality of actuators spaced apart along the width of the slot die. The applicator slot is in fluid communication with a fluid flow path through the slot die. Each actuator of the plurality of actuators is operable to adjust the height of the fluid flow path at its respective location to provide localized adjustment of fluid flow through the applicator slot.

Next, a controller, such as controller 300, is provided that communicates with each actuator (step 604). The controller is configured to set the position of each actuator according to one of a plurality of individual settings, such as a measured position of sensor 230 and/or a stepper motor setting for motor 210.

Using fluid dynamics and a digital model of slot die 10, such as a solid model of slot die 10, controller 300 predicts a set of individual settings from a plurality of individual settings that correspond to a preselected die cavity pressure. (step 606). In different embodiments, controller 300 may retrieve the preselected die cavity pressure from a non-transitory computer readable medium or may receive the preselected die cavity pressure from user input.

In different embodiments, the predicted settings may correspond to measurements from sensors 230 and/or individual position settings of motor 210. Sensor 230 may provide more accurate position information to controller 300 than that provided by motor 210. Thus, the controller can predict the settings of the actuator assembly 200 based on measurements from the sensor 230 and instead of directly driving the motor 210 up to a number of steps corresponding to the predicted position. Motor 210 can be operated to position output shaft 222 according to a setting.

The fluid dynamics, known fluid properties of the extrudate, and the digital model of the die allow the controller 300 to predict the individual settings of the actuators of the slot die 10. Modeling the extrudate flowing through the die is the applicator slot width, the distance from the manifold cavity to the outlet of the applicator slot, and the narrow dimension of the applicator slot between the two parallel surfaces that define the slot itself. Many aspects of the die itself can be incorporated, including slot height.

Any number of equations may be used to predict the settings of actuator assembly 200 of slot die 10 corresponding to a preselected die cavity pressure. For example, predicting the optimal settings for the actuator assembly 200 of the slot die 10 may include modeling heat transfer and heat dissipation throughout the slot die 10 and the extrudate. As previously discussed, such models may rely on finite element analysis or use more general equations to determine the value of the actuator assembly 200 of the slot die 10 corresponding to a preselected die cavity pressure. The settings may be predicted.

Once the controller 300 predicts the settings of the actuator assembly 200 of the slot die 10 that correspond to the preselected die cavity pressure, the slot die 10 will move the extrudate with the actuator assembly 200 positioned according to the predicted set of settings. through the fluid flow path and out of the applicator slot 6 (step 608).

During operation of the slot die 10, the controller measures the die cavity pressure at a suitable measurement point within the die cavity 4 or within the flow path, which may occur before or after the fluid flow path inlet 5 (step 610). For example, controller 300 may receive input from a sensor that directly measures die cavity pressure within die cavity 4 . Using the measured die cavity pressure, fluid dynamics, and digital model of the die, controller 300 then makes adjustments to the predicted set of personalized settings to more closely match the preselected die cavity pressure. Determine if die cavity pressure can be provided.

If the controller 300 determines that adjustments to the predicted set of individual settings can provide a die cavity pressure that more closely matches the preselected die cavity pressure, the controller adjusts the preselected die cavity pressure. A set of improved individualizations from the plurality of individualizations corresponding to pressure is predicted (step 612). While continuing to operate the slot die by passing extrudate through the fluid flow path and out of the applicator slot, controller 300 repositions the actuator according to the improved set of predicted individual settings (step 614). Steps 610, 612, and 614 may be repeated until the controller 300 determines that the predicted set of settings cannot be improved and/or at periodic intervals to maintain the desired die cavity pressure. can.

In some embodiments, the technique of FIG. 6 can be combined with the technique of FIG. 5. For example, controller 300 may attempt to provide a cross-web profile with a constant slot height while also maintaining a preselected die cavity pressure. In such embodiments, the controller 300 uses the same fluid dynamics and digital model of the die described with respect to FIGS. 5 and 6 to provide both a specific cross-web profile and a preselected die cavity pressure. Settings for actuator assembly 200 can be determined. In one example, pressure control allows control of a die positioned to coat a strip or precise width. Additionally, pressure control can be achieved if a sensor detecting strip width in communication with controller 300 is utilized to select die pressure control. The set of personalized settings (step 514) is saved as a recipe for future retrieval, which may be minutes, hours, or years later when similar materials, extrusion or coating properties, and processing conditions are required. Can be used at a future point.

FIG. 7 is a flowchart illustrating a technique for clearing a slot die by increasing the height of the fluid flow path adjacent each of the actuators while continuing to operate the die. Although not limited to the slot dies disclosed herein, for clarity, the technique of FIG. 4) will be explained. In different embodiments, the technique of Figure 7 can be applied to a film slot die, a multilayer slot die, a hot melt extrusion coating die, a drop die, a rotating rod die, an adhesive slot die, a solvent coating slot die, an aqueous coating die, a slot-fed knife die, an extrusion It can be utilized for replication dies, vacuum contact dies, or other slot dies.

First, a slot die such as slot die 10 is prepared (step 702). The slot die includes an applicator slot extending along the width of the slot die and a plurality of actuators spaced apart along the width of the slot die. The applicator slot is in fluid communication with a fluid flow path through the slot die. Each actuator of the plurality of actuators is operable to adjust the height of the fluid flow path at its respective location to provide localized adjustment of fluid flow through the applicator slot.

Next, a controller, such as controller 300, is provided that communicates with each actuator (step 704). The controller is configured to set the position of each actuator according to one of a plurality of individual settings, such as a measured position of sensor 230 and/or a stepper motor setting for motor 210. The controller 300 then uses the controller to position each of the actuators according to the set of individual settings selected from the plurality of individual settings (step 706), and the slot die 10 positions the actuator assembly 200 according to the set of individual settings selected from the plurality of individual settings (step 706). In this state, the extrudate is operated by passing the extrudate through the fluid flow path and out of the applicator slot 6 (step 708).

Defects in the extrudate profile after the extrudate exits the applicator slot are then observed, either by the controller 300 or by the user, for example. As explained in relation to Equation 3, any small disturbance to the flow within the die slot will disrupt the flow of liquid ejected from the die slot, thus affecting the cross-web uniformity of the extrudate or coating. effect. Such turbulence is often associated with gel or particulates trapped in the die slot itself. In coatings, this flow obstruction results in streaks, or in wider cases bands, in the coating. In film extrusion, this results in undesirable die lines. For this reason, it is desirable to allow impurities to pass through the die.

When defects in the extrudate profile are observed after the extrudate exits the applicator slot, the controller 300 directs the extrudate through the fluid flow path to allow impurities to pass through the die. While continuing to exit the applicator slot, the height of the fluid flow path adjacent each of the actuator assemblies 200 is increased (step 710). For example, controller 300 may operate actuator assemblies 200 in unison or sequentially to increase the height of the fluid flow path through slot die 10.

After increasing the height of the fluid flow path adjacent each of the actuators to allow turbulence to clear the die, the controller continues to pass the extrudate through the fluid flow path and out of the applicator slot. repositioning each of the actuators with the controller according to the original set of individual settings, i.e., the most recent set of adjusted settings before the purge operation, with the actuators positioned according to the original set of individual settings; , resumes operation of the slot die (step 712). In some embodiments, repositioning the actuator according to the original set of individualizations includes increasing the height of the fluid flow path adjacent the actuator for less than 15 minutes, less than 5 minutes, less than 2 minutes, or even within 30 minutes, such as less than 1 minute.

FIG. 8 is a flowchart illustrating a technique for purging a slot die by substantially closing the fluid flow path adjacent each of the actuators while continuing to operate the die. Although not limited to the slot dies disclosed herein, for clarity, the technique of FIG. 4) will be explained. In different embodiments, the technique of FIG. 8 can be applied to a film slot die, a multilayer slot die, a hot melt extrusion coating die, a drop die, a rotating rod die, an adhesive slot die, a solvent coating slot die, an aqueous coating die, a slot-fed knife die, an extrusion It can be utilized for replication dies, vacuum contact dies, or other slot dies.

First, a slot die such as slot die 10 is prepared (step 802). The slot die includes an applicator slot extending along the width of the slot die and a plurality of actuators spaced apart along the width of the slot die. The applicator slot is in fluid communication with a fluid flow path through the slot die. Each actuator of the plurality of actuators is operable to adjust the height of the fluid flow path at its respective location to provide localized adjustment of fluid flow through the applicator slot.

Next, a controller, such as controller 300, is provided that communicates with each actuator (step 804). The controller is configured to set the position of each actuator according to one of a plurality of individual settings, such as a measured position of sensor 230 and/or a stepper motor setting for motor 210. The controller 300 then positions each of the actuators using the controller according to the set of individual settings selected from the plurality of individual settings, and the slot die 10 positions the actuator assembly 200 according to the set of individual settings. In this state, the extrudate is operated by passing the extrudate through the fluid flow path and out of the applicator slot 6 (step 806).

Next, either the user or the controller 300 decides to interrupt the extrusion process through the slot die 10. Accordingly, controller 300 substantially closes the fluid flow path adjacent each of actuator assemblies 200 (step 808). For example, controller 300 may operate actuator assembly 200 substantially in unison or sequentially relative to the fluid flow path through slot die 10.

It may be undesirable to stop the flow of extrudate through the slot die 10, for example, it may take a significant amount of time during start-up to reach each equilibrium temperature of the slot die 10 and the extrudate. Additionally, in the case of heated extrudates, stopping flow can undesirably result in thermal degradation of stagnant material within the flow system. To this end, slot dies such as slot die 10 may include a purge valve (not shown). The extrudate may continue to flow through the slot die by purging the extrudate from the purge valve once the fluid flow path is substantially closed (step 810). For example, the purge valve may operate as a pressure relief valve when the controller 300 substantially closes the fluid flow path adjacent each of the actuator assemblies 200 due to increased pressure within the die cavity 4. It may be opened automatically. In other embodiments, the purge valve may be actively opened by either controller 300 or an operator.

After substantially closing the fluid flow path adjacent each of the actuator assemblies 200, and ready to resume operation while continuing to purge extrudate from the purge valves, the controller 300 performs the operations according to the original set of individual settings. Reposition each of the actuators (step 812). Additionally, the purge valve is closed, either automatically or manually, to resume operation of the slot die (step 814). In some embodiments, repositioning the actuator according to the original set of individualizations to resume operation of the slot die with the actuator positioned according to the set of individualizations substantially repositions the fluid flow path. The closing may take place within 30 minutes, such as less than 15 minutes, less than 5 minutes, less than 2 minutes, or even less than 1 minute.

FIG. 9 shows a strip coating 900 that includes strips 904 forming a strip pattern produced by iteratively adjusting the actuator position settings of a slot die. Strips 904 were simultaneously extruded along direction 902 from a single die, such as slot die 10. In particular, strip coating 900 provides strips 904 with varying widths.

A slot die, such as slot die 10, is configured to position each of the actuators using a controller according to a first set of individual settings selected from a plurality of individual settings; In this state, the extrudate can be operated to produce strip 904 by passing the extrudate through the fluid flow path and out of the applicator slot. The controller 300 can then use the controller to change the position of the actuator to produce strips having varying widths while passing the extrudate through the fluid flow path and out of the applicator slot.

For example, the controller 300 may switch between successive sets of personalized settings, including a first set of personalized settings, such that the varying widths of the strips 904 provide a substantially repeating pattern such as that shown in FIG. May be cycled. The controller 300 continues to vary the position of the actuator while passing the extrudate through the fluid flow path and out of the applicator slot for a period of more than 30 minutes, more than 1 hour, more than 3 hours, or even more. Varying widths can be created in the extrudate over a period of more than 10 minutes, such as a period of more than 12 hours.

FIG. 10 shows an extrudate 910 containing a pattern produced by iteratively adjusting the slot die actuator position settings. Extrudate 910 was extruded from a die, such as slot die 10, along direction 912. As shown in FIG. 10, light areas represent relatively thicker portions of the patterned product and dark areas represent relatively thinner portions of the patterned product. Specifically, extrusion 910 includes a series of ridges that extend at an angle across the width of extrusion 910.

A slot die, such as slot die 10, is configured to position each of the actuators using a controller according to a first set of individual settings selected from a plurality of individual settings; In this state, extrudate 910 can be operated to produce extrudate 910 by passing the extrudate through the fluid flow path and out of the applicator slot. The controller 300 can then use the controller to change the position of the actuator to produce patterned features on the extrudate while passing the extrudate through the fluid flow path and out of the applicator slot. can.

In some examples, controller 300 may select a randomized setting from a plurality of individual settings such that the patterned features of the extrudate are randomized pattern features. The randomized settings selected by the controller match pre-selected specifications for the randomized pattern features; for example, such pre-selected specifications include average extrudate thickness, product thickness can represent the standard deviation of the product profile or other product profile specifications.

In other embodiments, the controller 300 includes a series of individual settings, including a first set of individual settings, such that the patterned features of the extrudate are in a substantially repeating pattern, such as that shown in FIG. may cycle between the sets. The controller 300 continues to vary the position of the actuator while passing the extrudate through the fluid flow path and out of the applicator slot for a period of more than 30 minutes, more than 1 hour, more than 3 hours, or even more. Patterned features can be produced in the extrudate over a period of time greater than 10 minutes, such as a time period greater than 12 hours.

Controller 300 can retrieve the first set of personalized settings and preselected specifications for pattern features from the non-transitory computer readable medium. In other embodiments, controller 300 may receive a first set of personalization settings and preselected specifications for pattern features from a user input.

11A-11D illustrate an example user interface 920 for a slot die controller. User interface 920 can interact with controller 300 to control operation of the set of actuator assemblies and control operation of the slot die. As shown in FIG. 11A, user interface 920 includes a display of selected slot die operating program 924, die temperature 926, and die pressure 928. User interface 920 also includes a set of selectable buttons that control the operation of the die, as well as a corresponding cancel button, which is selectable by the user if the selectable button is inadvertently activated. Allows you to cancel the selection of one of the buttons. Selectable button 930 is configured to initiate a purge operation, such as the techniques disclosed herein with respect to FIG. Selectable button 932 is configured to initiate a slot clearing operation such as the techniques disclosed herein with respect to FIG. Selectable button 934 is configured to resume slot die operation according to previous settings after a purge or slot clear operation.

FIG. 11A also shows a profile tab 940. Selecting the Profile tab 940 displays a graph containing a representation of the extruded product profile measured across the width of the extruded product. The chart also displays the actuator number relative to the width of the extruded product. Additionally, profile tab 940 includes a scroll bar 942, which can be used to view extruded product profiles at different times. However, as shown in FIG. 11A, the scroll bar 942 is in the forwardmost position so that the profile tab 940 displays the current extruded product profile and does not display a historical record of the extruded product profile.

FIG. 11B shows slot height tab 950. Selecting the slot height tab 950 displays a graph that includes a representation of the slot height across the width of the die. The chart also displays actuator number versus slot height width. Additionally, the slot height tab 950 includes a scroll bar 952, which can be used to view the slot height at different times. However, as shown in FIG. 1IB, the scroll bar 952 is in the forward-most position such that the slot height tab 950 displays the current extruded product profile and does not display a historical record of the extruded product profile. . Slot height tab 950 further includes a selectable button that can be used to save the current actuator settings for later retrieval.

FIG. 11C shows an auto-select average setpoint tab 960. Selecting the Auto Select Average Set Point tab 960 displays the actuator position associated with each actuator of the slot die, the actual current height of the die slot corresponding to each actuator position, and the extrudate measured by weight and height. Display a chart that includes thickness. In addition, the auto-select average setpoint tab 960 includes a selectable update setpoint button 964. Selecting the selectable update setpoint button 964 causes the controller to calculate a new setpoint that limits the variability of the product profile. The new setpoint is then displayed on the chart in the auto-select average setpoint tab 960. A selectable button 966 allows the user to then change the position of the actuator according to the calculated new set point.

FIG. 11D shows an auto-select pressure tab 970. Selecting the auto-select pressure tab 970 displays the actuator position associated with each actuator of the slot die, the actual current height of the die slot corresponding to each actuator position, and the extrudate thickness measured by weight and height. Display a chart containing. In addition, auto-select pressure tab 970 includes a selectable update setpoint button 974. Selecting the selectable update setpoint button 974 causes the controller to calculate a new setpoint according to the pressure indicated in the “New Pressure Setting Box” 978. The new set point is then displayed on the chart in the Auto Select Pressure tab 970. A selectable button 976 allows the user to then change the position of the actuator according to the calculated new set point.

FIG. 12 illustrates a technique for retrofitting a slot die with an actuator assembly, such as the set of actuator assemblies 200 (FIG. 4). In different embodiments, the technique of FIG. 12 can be applied to a film slot die, a multilayer slot die, a hot melt extrusion coating die, a drop die, a rotating rod die, an adhesive slot die, a solvent coating slot die, an aqueous coating die, a slot-fed knife die, an extrusion It can be used for replication dies, vacuum contact dies, or other slot dies.

First, a slot die is prepared (1202). The slot die includes an applicator slot extending along the width of the slot die and a plurality of actuation mechanisms spaced apart along the width of the slot die. The applicator slot is in fluid communication with a fluid flow path through the slot die. Each actuator of the plurality of actuation mechanisms is operable to adjust the height of the fluid flow path at its respective position to provide adjustment of fluid flow through the applicator slot. The slot die may be operated using multiple actuation mechanisms to control the height of the fluid flow path across the width of the slot die.

In different embodiments, the actuation mechanism includes one or more of a thermally adjustable bolt, a differential bolt, a piezoelectric actuator, a pneumatic actuator, and/or a hydraulic actuator. In one example, the actuation mechanism includes a thermally adjustable bolt, and the technique for retrofitting a slot die with a thermally adjustable bolt includes cross-section of the extrudate after it exits the applicator slot. evaluating the web profile and adjusting one or more of the actuation mechanisms such that the cross-web profile of the extrudate after it exits the applicator slot more closely matches the preselected cross-web profile. adjusting the relative positions with their respective thermally adjustable bolts.

In one exemplary actuation mechanism, the applicator slot is pressed against the flexible die lip using a lever supported by a rotating shaft as a fulcrum, with an actuation rod axially displaced by the body of the slot die. Adjustment can be made by applying a load or a tensile load. The rotational force of the lever is converted into an axial force of the actuating rod, and this axial force becomes a pressing or tensile load acting on the flexible die lip. The lever can apply a force directly to the actuating rod at the point of action of the lever.

In another embodiment, a thermally adjustable bolt automatically adjusts the applicator slot using a plurality of adjustment pins coupled to respective thermoelectric elements disposed on the flexible die lip. . The thermoelectric element may be controllable by a controller to adjust the applicator slot through the action of a mechanical force applied to the flexible die lip by a corresponding adjustment pin through expansion or contraction of the thermoelectric element. As a further option, the actuation mechanism may include providing at least two adjustment pins and/or thermoelectric elements that are adjusted simultaneously.

Further aspects of the above, along with other variations, are described in US Patent No. 9,700,911 (Nakano) and PCT Patent Publication No. WO 2019/219724 (Colell et al.).

The actuation mechanism is then removed from the die housing (1204). In place of the actuation mechanism, a plurality of actuator assemblies, such as actuator assembly 200, are installed (1206). Each actuator assembly of the plurality of actuator assemblies is operable to adjust the height of the fluid flow path at its respective location to provide localized adjustment of fluid flow through the applicator slot.

Next, a controller, such as controller 300, is provided and a communication link is formed between each actuator assembly and the controller (1208). The controller is configured to set the position of each actuator assembly according to one of a plurality of individual settings, such as a measured position of sensor 230 and/or a stepper motor setting for motor 210.

Using fluid dynamics and a digital model of the slot die, controller 300 predicts a set of individual settings from a plurality of individual settings that correspond to a preselected die cavity pressure. In different embodiments, controller 300 may retrieve the preselected die cavity pressure from a non-transitory computer readable medium or may receive the preselected die cavity pressure from user input.

In different embodiments, the predicted settings may correspond to measurements from sensors 230 and/or individual position settings of motor 210. Sensor 230 may provide more accurate position information to controller 300 than that provided by motor 210. Thus, the controller is able to predict the settings of the actuator assembly 200 based on measurements from the sensor 230 and instead of directly driving the motor 210 up to a number of steps corresponding to the predicted position. Motor 210 can be operated to position output shaft 222 according to a setting.

The fluid dynamics, the known fluid properties of the extrudate, and the digital model of the die allow the controller 300 to predict the individual settings of the actuator assembly. Modeling the extrudate flowing through the die is the applicator slot width, the distance from the manifold cavity to the outlet of the applicator slot, and the narrow dimension of the applicator slot between the two parallel surfaces that define the slot itself. Many aspects of the die itself can be incorporated, including slot height.

Any number of equations can be used to predict the settings of the actuator assembly, where the predicted settings correspond to, for example, a preselected cross-web profile and/or a preselected die cavity pressure. Good too. For example, predicting the settings of the actuator assembly may include modeling heat transfer and dissipation throughout the slot and extrusion.

Once the controller 300 predicts a setting for the actuator assembly 200 of the slot die 10 that corresponds to a preselected die cavity pressure, the slot die fluidically moves the extrudate with the actuator assembly positioned according to the predicted set of settings. It is operated by passing it through the flow path and out of the applicator slot (1212).

13-20 illustrate a technique for manipulating die lip shape by applying a force generally parallel to the width of the die, where the force application mechanism is applied to a flexible die lip in accordance with the techniques disclosed herein. or provided and largely contained within the restrictor/choker bar.

The flatness of the coating and extrusion die during processing is important to product quality. The die lip can be operated by a differential bolt, a heated bolt, or a piezoelectric device. Another alternative is with an actuator assembly, such as actuator assembly 200. In all cases, these devices are intended for global control of the die lip by pushing or pulling at discrete locations. In all of these cases, the push/pull is in a direction generally perpendicular to the width of the die. According to the present disclosure, the die lip shape is instead manipulated by applying a force generally parallel to the width of the die, with a force application mechanism largely housed within the flexible die lip or restrictor/choker bar. is provided. For example, the flatness of the die lip can be manipulated by expanding the metal near the die lip, thereby changing the shape of the die lip between discrete control points, as shown in FIG. This technique is similar to a die with muscles that can be flexed between positioning devices. The slot die profile shown in Figure 13 uses vertical notches (i.e., saw cuts) in the flexible die lip to allow for precise adjustment of the slot die profile to adjust the varying amounts of expansion of the flexible die lip. This shows how it can be quantified. An enlarged version of this chart is described later in FIG.

These techniques can be used in combination with conventional adjuster means to advantageously adjust the die slot between conventional die slot control element positions themselves, thus improving the spatial resolution of extrusion uniformity control. can do. In one embodiment, this can attenuate the effects of pressure deflections on flexible die lips or internal restrictor/choker bars between conventional adjusters to achieve improved extrusion uniformity.

The provided technology provides a force application mechanism that stretches or responds to allow localized deflection of the die lip or choker bar. Exemplary force application mechanisms include piezoelectric devices, heating elements, mechanical devices, pneumatic devices, and hydraulic devices. In one example, application of bolt torque through a stepped bolt element is used to expand the metal in the vicinity of the threads and change the profile at the lip of the die. In a further embodiment, the shoulder bolt also functions as a spindle for a die actuator assembly, such as actuator assembly 200. In another example, localized cooling or heating of the lip at points along the lip causes the adjacent metal to contract and change the profile at the die lip.

The techniques disclosed herein can be utilized as the sole adjustment means for the conventional adjuster-free "fixed slot" type dies discussed above.

In a further example, using the techniques disclosed herein, the die can be " Coating dies can be created with built-in pressure relief features. Alternatively, this same strategy can be used to simply create a "flat" die slot during die assembly.

The pressure relief shape can be based on predetermined force or actuator settings, any of which can be provided automatically, semi-automatically, or manually. In an exemplary embodiment, the predetermined force described above is parallel to the width of the slot die and locally expands or contracts a choker bar or flexible die lip parallel to the width of the slot die. The settings of the force application mechanism can be automatically determined, for example, based on a target cross-web slot height profile average across the width of the slot die.

As mentioned above, any small disturbance to the flow within the die slot will disrupt the flow of liquid ejected from the die slot, thus affecting the cross-web uniformity of the coating or extruded sheet.

Extrusion dies typically have flexible die lips so that the slot can be adjusted to improve uniformity of the extruded film. Several techniques are used to flex the lip, including differential bolts, thermal bolts, piezoelectric devices, and actuators, as described above. In all of these cases, the push/pull is in a direction generally perpendicular to the width of the die. The spacing of the devices used to move the lips varies from about 1 inch (2.54 centimeters) to as much as 2.75 inches (7 centimeters). It is difficult to influence these interstitial areas by actuating the moving device, so it is important to have a smooth, continuous surface on the die lip between the devices. Generally, it is desirable to provide fine spatial resolution of extrusion uniformity control. However, spatial resolution is limited by the number of actuators that can be placed adjacently along the width of the die. With the techniques disclosed herein, the spatial resolution of tunable dies (eg, flexible lip or choker bar types) can be essentially doubled.

Furthermore, pressure deflection between conventional adjusters is a fundamental limitation for all adjustable dies. In order for the lip or choker bar to be adjustable, it must be flexible. However, in order for a flexible lip or choker bar to resist undesirable pressure deflections in the span between the adjusters, it is necessary to make it more rigid, in direct contrast to the need to make it adjustable. With the present disclosure, the die lip can remain more flexible, which is important to enable extrusion flow uniformity adjustment while directly mitigating the effects of pressure deflection between traditional actuators. be.

A force application mechanism capable of pushing and pulling the flexible lip or choker bar is generally engaged with the lip or choker bar. This may for example be provided by a threaded connection. In some examples, the threaded connection includes a shoulder bolt. As disclosed herein, the lip profile can be manipulated by controlling stepped bolt torque. Tightening or applying torque to the bolt compresses the material around the threads, and any expansion near the lip can be used to modify the die lip profile. This may be particularly useful when combined with actuator assembly 200.

In a further example, the techniques of this disclosure can be used to create a coating die with a "built-in" pressure relief feature. Precision die lip adjustment involves mechanical bolts that rely on threaded engagement, thermal bolts that locally heat the lip and adjust the lip position through thermal expansion, electrically moved piezoelectric devices, and stepper motors to push the lip. This can be done using several methods, including using actuators, or a combination of these. The intention of the adjustment mechanism in all of these is to move the lip in discrete positions, which are aligned with the device and typically spaced 2.5 cm to 7 cm apart. The shape of the die lip between devices is not controlled but is responsive to device movement, both with and without the influence of die pressure.

According to the techniques disclosed herein, the shape of the die lip is intentionally manipulated by controlling the attachment of the pressing device. In the case of a mechanical actuator pushing the spindle, the spindle is screwed into the die lip. This also applies to thermal bolts and differential bolts, alone or in combination with piezoelectric devices. If desired, two or more thermal bolts placed within the choker bar or flexible die lip can be used to provide non-uniform thermal expansion along the choker bar or flexible die lip. It is.

Because piezoelectric devices and thermal bolts have limited extension, they are often combined with differential bolts for coarse adjustment.

FIG. 14 shows an enlarged view of a flexible die block 1300 with a bolt 1302 attached to a flexible die lip 1304 and serving as a force application mechanism. The die was fabricated from precipitation hardened stainless steel commonly referred to as 15-5 PH (obtained under the trade designation "UNS S15500" from Crucible Materials Corporation, Syracuse, NY). Bolt 1302 can connect to one or more actuator assemblies, such as actuator assembly 200. As shown, the flexible die lip includes a plurality of regularly spaced notches 1306 to facilitate flexing of the flexible die lip 1304 as the metal expands.

FIG. 15 shows an interferometer plot (using a laser interferometer provided by ZYGO Corporation (Middlefield, CT)) of the die lip shown in FIG. 14 without the spindle attached to the die lip, and FIG. 16 shows an interferometer plot with the spindle attached to the die lip. Figure 15 shows an interferometer plot of the die lip shown in Figure 14 installed. In these figures, the dashed line represents the slot die parting line and the downward arrow in FIG. 16 indicates the actuator spindle position.

For actuators that are spaced 2.5 inches (6.4 centimeters) apart due to their physical size, locally bending the choker bar or flexible die lip is optional. There can be one or more notches machined into the lip to facilitate. Threaded connection of the device to the die lip causes movement of the lip between the primary positioning devices. This example is shown in FIGS. 15 and 16 for a test die with five actuators. FIG. 15 shows the profile near the lip edge without the spindle attached, and FIG. 16 shows a similar plot with the spindle attached and torqued to 35 ft-lbs (47 Newton meters). Data was collected using an interferometer on the top die surface near the slot exit. Here, the torque applied to the threaded connection acting against the shoulder of the bolt creates compressive stresses in the material in the vicinity of the threads. This effectively "pushes" away from the threaded connection and effectively expands the material between the locating devices, thus changing the profile between the locating devices. By increasing the torque, this effect can be increased, as explained below.

The die shown in Figure 13 had 15 actuators and measurements were taken at each actuator as well as at the midpoint and quarter point. First, the spindle was left loose and the die profile was measured. Various levels of torque were then applied to the spindle. The profile is shown in FIG. The vertical lines at integer positions on the plot represent the spindle position, and the amplitude of each curve represents the variation between actuators. The solid line labeled "Slack" represents the profile of the die lip without the spindle. Each of the other series in the plot represents increasing torque. It can be seen that the variation increases with the level of torque applied to the spindle. FIG. 18 shows the linear relationship between actuator-to-actuator variation and applied torque. FIG. 18 plots spindle torque versus average deviation between actuators, showing the effect of spindle torque on slot profile.

In order to produce flat films or coatings, it may be necessary to control die slot uniformity. One technique to improve flatness is to grind the surface of the die slot after installing the spindle, which can eliminate the variations seen in FIG. 17. However, depending on the material being coated or extruded, different levels of die cavity pressure exist, which accounts for variation between positioning devices. As previously mentioned, it has typically been difficult to control the position of the die lip in position between the positioning devices. This variability can be particularly pronounced when the spacing of the positioning devices increases and the die pressure is relatively high, such as with actuators. Finite element modeling can be used to predict the die lip profile using the effects of positioning devices and die cavity pressure.

FIG. 19 shows the lip profile of the test die shown in FIG. 14 with representative cavity pressures applied. Actuator-to-actuator variation has been found to be approximately 77 millionths of an inch (or 1.96 micrometers). The direction of deflection is opposite to the direction of deflection due to torque, which in combination makes the die lip profile more uniform. Therefore, based on the relationship between average deviation and torque shown in FIG. Torque can be selected.

Differential thermal expansion can also be used to compensate for pressure-induced die slot deflection. In a practical example, Table 1 below characterizes the vibration of the cross-web slot height profile at three locations along the applicator slot. These measurements demonstrate that by appropriately applying heat to the die lip segment to induce thermal expansion in the die lip segment, it may be possible to substantially eliminate the "waviness" in the cross-web slot height profile. It has been proven. In this example, heat was applied using electrical resistance heat tape wrapped around the die lip segment. Heat can also be applied to the actuator spindle near where it is attached to the flexible die lip.

Notably, the desired temperature of the die lip segment can be either higher or lower than the temperature of the die, depending on the level of heat input. If the temperature near the die lip segment is lower than the temperature of the rest of the die, it is possible to reverse the peaks and valleys observed in the cross-web slot height profile of the applicator slot. This is shown in FIG.

Note that in these embodiments, die lip profile control is described as a function of bolt torque. However, based on theorized control mechanisms, any method of applying controlled expansion or even contraction of material in the vicinity of the die lip is expected to have similar effects. This can include mechanical, thermal or electrical methods. Additionally, although the example here refers to expansion radially away from the axis of the spindle, this may be in any direction, for example parallel to the die lip.

In a further example, techniques disclosed herein may be used to manipulate a die with force elements (and associated forces) that create a desired pressure relief configuration when removed and the die is assembled. Coating dies can be created with "built-in" pressure relief features, such as by grinding. For example, fluid pressure typically deflects the die shape by 1.27 micrometers in the span between actuators, but the required spindle torque using a stepped bolt feature causes a deflection of 2.54 micrometers. Assume that it is induced. In this case, the coating die can be ground with a shoulder bolt at a lower torque level that will result in a non-flat shape when removed. However, when spindles with stepped bolt features are inserted and torqued to their specifications, the desired 1.27 micrometer deflection alleviates the pressure effects and provides the desired flat shape.

This strategy can also be used for die elements that do not include a stepped bolt spindle attachment for the actuator. For example, if the actuator attachment does not induce deflection, such as a shoulder bolt, you can add elements for use in the grinding process just to deflect the die lip or choker bar, and when they are removed, the lip can have a desired shape profile that resists pressure deflection.

In the examples above, die lip profile control is described as a function of bolt torque. However, based on theorized control mechanisms, any method of applying controlled expansion or even contraction of material in the vicinity of the die lip can have a similar effect. Useful force application mechanisms include mechanical, thermal, or electrical methods, piezoelectric devices, heating elements, mechanical devices, pneumatic devices, and hydraulic devices. Additionally, although the example here refers to expansion radially away from the axis of the spindle, this may be in any direction, for example parallel to the die lip. The technology disclosed herein involves manufacturing strategies that induce the desired flow slot shape, suitable means as a "die setup" such as spindle torque as described above, and die lip profile shape on-line during the extrusion or coating process itself. including fully controllable means of adjusting the

It may be desirable to reduce the effective width of the applicator slot. This may be required, for example, when producing films with lateral dimensions that are significantly smaller than the overall width of the slot die. In order to make such films using the same slot die, it is advantageous to insert one or more deckles into the applicator slot to interrupt the flow of extrudate along at least a portion of the applicator slot. It can be. The deckle is typically tightly clamped between opposing die lips to prevent the deckle from falling off during operation of the slot die.

In some cases, the deckle can also function as a shim that changes the slot height of the applicator slot in its neutral or rest position. This neutral position is the position when the flexible die lip or choker bar is not flexed open or closed by the force application mechanism.

In the predictive control scheme described above, an actuator dynamically directs fluid flow through an applicator slot using a choker bar or flexible die lip based on incoming extrudate thickness (i.e., caliper) data. Incorporating such a deckle into an extrusion process can be a technical challenge, as it is configured to adjust and would normally not be aware of its presence. This problem can be overcome by a process known as "freezing," in which at least some actuator settings are assigned fixed values during slot die operation, while other actuator settings are It does not change even if it is repeatedly corrected during operation.

For clarity in the following paragraphs, "blocked zone" refers to the area along the width of the slot die, aligned with the deckle, where extrudate cannot pass through the applicator slot. "Unblocked zone" refers to the area along the width of the slot die that is not aligned with the deckle and allows extrudate to pass through the applicator slot. The deckle preferably has a thickness similar to that of the applicator slot in its neutral position to avoid creating discontinuities in slot height between blocked and unblocked zones. It has a certain quality.

In an exemplary process, at least a portion of the applicator slot of the slot die is blocked with a deckle to reduce the effective width of the applicator slot, and the slot die has at least some actuator settings blocked with a deckle. The at least some actuator settings are operated fixedly over the zone and dynamically over the unblocked zone of the applicator slot. To provide continuity between adjacent actuator positions, the control scheme preferably includes a die lip or choker bar slot height profile above the blocked zone and a die lip or choker bar above the adjacent unblocked zone. Constrain the assigned actuator settings such that the bar slot height profile converges to the same value where the blocked and unblocked zones meet.

Preferably, the convergence of the cross-web slot height profiles where the blocked and unblocked zones come together is a monotonic convergence. In some cases, the convergence is sinusoidal convergence rather than monotonic convergence. However, even if the convergence is sinusoidal, the actuator settings in the vicinity of the transition point between the blocked and unblocked zones will reduce the cross-web profile obtained in the absence of such constraints. Preferably, the controller is automatically or semi-automatically constrained to reduce the amplitude of the oscillations.

The deckle can be used even if the actuator is not engaged to the die lip. For example, multiple actuators can be used that engage choker bars across the width of the die slot even if a portion of the applicator slot is blocked by one or more deckles at the die exit. In the presence of a deckle, the exact configuration of the choker bar does not control flow in the blocked slot region, but nevertheless bends interaction (i.e., convolution) with the unblocked region along the die slot. have some influence as a result of.

In the control scheme described above, where the actuator is engaged to the choker bar, the actuator corresponding to the blocked zone of the slot is simply locked in a fixed position ("freeze mode"). This fixed position can be determined based on the cross-web slot height profile average along only the unobstructed zone of the applicator slot. Other control modes are also possible, as explained below.

In a second control mode, the actuator settings are predictively programmed to reach a fixed target slot position above the blocked zone of the slot ("freeze slot mode"). Here, the actuator is not frozen and is manipulated by the controller, for example based on fluid physics calculations, to reach a fixed slot profile. In some embodiments, this is an iterative process and the actuator settings may be adjusted more than once to converge on the desired fixed slot profile.

In a third control mode, the choker bar along the blocked zone moves together with the adjacent outer portion of the open die slot ("slave mode"). In other words, the actuator above the blocked zone becomes a "slave" of the last actuator in the unblocked zone.

In one embodiment, this freeze slot mode can be achieved by manipulating the fluid physics within the freeze slot actuator zone. For example, assume that actuators #1 and #2 are frozen, while the segment of the applicator slot corresponding to actuator #3 is unobstructed and yields good caliper data. In this case, the average caliper measurements above the unblocked actuator zones can be used in place of the caliper data that is not present in the blocked actuator zones (i.e., actuators #1 and #2).

上に示したように、行列法は、アクチュエータ位置を操作してそれらの畳み込み相互作用を考慮することによって、スロットを一定に保持する。 Mathematically, this result can be achieved as follows using the matrix method described in PCT Patent Publication No. WO 2012/170713 (Secor et al.).

As shown above, the matrix method holds the slots constant by manipulating the actuator positions and considering their convolutional interactions.

Adjusting the relative position of Freeze Slot 1 or Freeze Slot 2 compared to Actuator 3 may (1) suspend automatic fluid physics control and (2) require the position of Actuator #1 and/or #2. (3) and then (3) restarting the automatic fluid physics control. As a result, actuators #1 and #2 remain slaves, but their positions are defined relative to the new starting point considered at the adjusted slot height B'i.

In the above-mentioned "freeze mode", the position at which the actuator with fixed settings transitions to the actuator with dynamic settings can be advantageously adjusted by the operator based on the application at hand. This transition position can be made to one or more deckle positions within the applicator slot. For example, the aggressiveness of the freeze can be adjusted according to the following three options (in these descriptions, "i" represents the actuator number):
(1) Freeze option A: Freeze when deckle passes i (i+1) (most aggressive).
(2) Freeze option B: Freeze at (i+1) when deckle passes (i+0.5) (moderately aggressive).
(3) Freeze Option C: Freeze at (i) when deckle passes i (least aggressive).
The above options assume that the deckle is placed on the left side of the die (lower actuator number side). If the deckles are installed on both sides of the die, the same principle applies to the mirror image on the opposite side (higher actuator number).

An important technical challenge in installing the deckle in the applicator slot when the actuator follows the control scheme described above is the sudden change in the slot height profile where the blocked and unblocked zones come together. This stems from the controller's tendency to overcompensate. This can produce an undesirable "kink" in the slot height profile, an artifact from sinusoidal convergence. Left uncorrected, this phenomenon can produce a "W" or "M" shape in the slot height profile, as shown by the dotted lines in FIGS. 21 and 22, respectively. In these figures, actuators #1 to #10 and #26 to #35 were frozen, but the remaining actuators #11 to #25 were not frozen.

To reduce or prevent the above-mentioned phenomenon, the predicted actuator settings near where this transition occurs can be further adjusted to improve the cross-web slot height profile along the unobstructed zone and the blocked zone. can yield monotonic convergence between the cross-web slot height profile averages above. In various embodiments, this adjustment can be made manually, automatically, or semi-automatically. The idealized results of this adjustment are represented by the solid lines in FIGS. 21 and 22, and the actual slot profile values are represented by the bar graphs. In the exemplary embodiment of FIG. 21, monotonic convergence was achieved for the deckle boundary on the left side of the chart, but not on the right side, leaving an undesirable kink in the slot height profile.

Continuity issues arise again when purging a slot die that has one or more deckles installed, particularly in configurations where the actuator is engaged to the flexible die lip. Once the flexible die lip is clamped onto the deckle, the actuator position along the deckle is essentially fixed. A conventional purge in which all actuators fully open the applicator slots causes the deckle to fall off. Further, opening the applicator slot completely only along the unobstructed zone is also problematic as it requires a discontinuity (or break) in the flexible die lip.

To solve this dilemma, the controller gradually decreases the degree of expansion along the transition zone between the unblocked and blocked zones, while Commands can be sent to the actuator to automatically or semi-automatically enlarge the cross-web slot height profile. The transition zone can extend over three, four, or even more than four consecutive actuators. This solution allows the applicator slot to be purged while providing a smooth transition of the slot height profile between the blocked and unblocked zones of the applicator slot.

The techniques described in this disclosure, such as those described with respect to controller 300, may be implemented at least partially in hardware, software, firmware, or any combination thereof. For example, various embodiments of the technology may include one or more microprocessors, digital signal processors (DSPs), application specific integrated circuits (DSPs) embodied in a controller, user interface, or other device. specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), or any other equivalent integrated circuits or discrete logic circuits, as well as any combination of such components. . The term "controller" may generally refer to any of the aforementioned logic circuits alone or in combination with other logic circuits, or any other equivalent circuit.

When implemented in software, the functionality ascribed to the systems and controllers described in this disclosure may include random access memory (RAM), read-only memory (ROM), non-volatile random access memory As instructions on a computer-readable storage medium such as non-volatile random access memory (NVRAM), electrically erasable programmable read-only memory (EEPROM), flash memory, magnetic media, optical media, etc. May be specific. The instructions may be executed to cause one or more processors to support one or more embodiments of the functionality described in this disclosure.

Various embodiments have been described in the preceding sections. These and other embodiments are within the scope of the following claims.

Furthermore, all references, patents, or patent applications cited in the above patent applications are hereby incorporated by reference in their entirety. In the event of any discrepancy or inconsistency between some of the incorporated references and this application, the information in the foregoing description shall prevail. The foregoing description is provided to enable one skilled in the art to practice the disclosure set forth in the claims, and should not be construed as limiting the scope of the disclosure, but rather limiting the scope of the disclosure. is defined by the claims and all equivalents thereof.

■

Furthermore, all references, patents, or patent applications cited in the above patent applications are hereby incorporated by reference in their entirety. In the event of any discrepancy or inconsistency between some of the incorporated references and this application, the information in the foregoing description shall prevail. The foregoing description is provided to enable one skilled in the art to practice the disclosure set forth in the claims, and should not be construed as limiting the scope of the disclosure, but rather limiting the scope of the disclosure. is defined by the claims and all equivalents thereof.
In addition to each embodiment, the following aspects will be added.
(Additional note 1)
A method of operating a slot die, the slot die comprising: an applicator slot extending along a width of the slot die, the applicator slot being in fluid communication with a fluid flow path through the slot die; at least one of the group consisting of a choker bar and a flexible die lip, the method comprising:
manipulating the shape of the choker bar or the flexible die lip by applying a force generally parallel to the width of the slot die using a force application mechanism;
Method.
(Additional note 2)
The method of clause 1, wherein the force generally parallel to the width of the slot die expands the flexible die lip or metal of the choker bar.
(Additional note 3)
3. The method of claim 1 or 2, wherein the force generally parallel to the width of the slot die is selected to create a pressure relief shape.
(Additional note 4)
The slot die further includes the choker bar, the slot die further includes a plurality of actuators spaced apart along the width of the slot die, and the plurality of actuators extend along the width of the choker bar. each actuator is engaged with the choker bar, each actuator controlling the height of the fluid flow path at each actuator location by providing local adjustment of the choker bar position within the fluid flow path; The method according to any one of appendices 1 to 3, wherein the method is operable to:
(Appendix 5)
The slot die further includes a plurality of actuators spaced apart along the width of the slot die, each actuator of the plurality of actuators for providing localized adjustment of fluid flow through the applicator slot. , being operable to adjust the height of the applicator slot at a respective position of each actuator.
(Appendix 6)
The slot die further includes the flexible die lip on one side of the applicator slot, and the plurality of actuators control the height of the applicator slot by moving the flexible die lip. The method according to appendix 5, which is operable to:
(Appendix 7)
7. The method of clause 6, wherein the flexible die lip includes a plurality of notches that facilitate locally bending the choker bar or flexible die lip.
(Appendix 8)
8. A method according to any one of clauses 1 to 7, wherein the force generally parallel to the width of the slot die either contracts or expands the metal forming the flexible die lip.
(Appendix 9)
grinding the slot die while applying the force generally parallel to the width of the slot die;
removing the force generally parallel to the width of the slot die so that the slot die assumes a pressure-reduced configuration after grinding the slot die;
The method according to any one of Supplementary Notes 1 to 8, further comprising:
(Appendix 10)
10. A method according to any one of clauses 1 to 9, wherein the force application mechanism comprises a heating element, a piezoelectric device, a mechanical device, a shoulder bolt element, a pneumatic device, or a hydraulic device.
(Appendix 11)
A method of operating a slot die, the slot die comprising: an applicator slot extending along a width of the slot die, the applicator slot being in fluid communication with a fluid flow path through the slot die; at least one of the group consisting of a choker bar and a flexible die lip; and a plurality of actuators spaced apart along the width of the slot die, each actuator of the plurality of actuators passing through the applicator slot. a plurality of actuators operable to adjust the height of the fluid flow path at a respective position of each actuator to provide localized adjustment of fluid flow, the method comprising:
locally expanding or contracting the choker bar or the flexible die lip of the slot die along a direction generally parallel to the width of the slot die, thereby causing the plurality of actuators to expand or contract the choker bar or the flexible die lip of the slot die; determining an actuator setting to adjust the cross-web slot height profile when engaging the gender die lip;
engaging the plurality of actuators with the choker bar or the flexible die lip based on the determined actuator settings;
including methods.
(Appendix 12)
Clause 11, wherein the choker bar or flexible die lip includes a plurality of notches extending generally parallel to a fluid flow direction to facilitate locally bending the choker bar or flexible die lip. Method described.
(Appendix 13)
A method of operating a slot die, the slot die comprising: an applicator slot extending along a width of the slot die, the applicator slot being in fluid communication with a fluid flow path through the slot die; at least one of the group consisting of a choker bar and a flexible die lip; and a plurality of actuators spaced apart along the width of the slot die, each actuator of the plurality of actuators passing through the applicator slot. a plurality of actuators operable to adjust the height of the fluid flow path at a respective position of each actuator to provide localized adjustment of fluid flow, the method comprising:
blocking a portion of the applicator slot with a deckle to reduce the effective width of the applicator slot;
using a controller to predict the set of personalized settings from a plurality of personalized settings based on a preselected cross-web slot height profile of an unobstructed zone of the applicator slot, the prediction comprising: , based on a known correlation between the set of personalized settings and a cross-web slot height profile of the extrudate;
setting the position of each actuator according to the set of predicted individual settings for the adjustment of the slot die;
including;
the actuator is fixed over the blocked zone of the applicator slot and dynamic over the unblocked zone of the applicator slot during operation of the slot die;
Method.
(Appendix 14)
The height profile along the unobstructed zone of the applicator slot is such that the height profile along the unobstructed zone of the applicator slot is such that the height profile along the unobstructed zone of the applicator slot 14. The method of claim 13, converging to an average height profile over the zone.
(Additional note 15)
1. A method of manufacturing an extruded article, the method comprising:
operating a slot die according to the method described in any one of appendices 1 to 14, and extruding an extrudate through the applicator slot of the slot die to obtain the extruded article;
including methods.
(Appendix 16)
A method of purging a slot die, the slot die comprising: an applicator slot extending along a width of the slot die, the applicator slot being in fluid communication with a fluid flow path through the slot die; a choker bar or flexible die lip extending along the width of the slot die; and a plurality of actuators spaced apart along the choker bar or flexible die lip, each actuator controlling fluid flow through the applicator slot. a plurality of actuators, each actuator being operable to adjust the height of the applicator slot at a respective location to provide localized adjustment of the applicator slot; one or more deckles that reduce the effective width of the applicator slot, the method comprising:
manipulating the shape of the choker bar or the flexible die lip by applying a force using the plurality of actuators to obtain a target cross-web slot height profile; fixed above the blocked zone of the applicator slot and dynamic above the unblocked zone of the applicator slot;
the plurality of actuators along the unblocked zone of the applicator slot, with the degree of expansion decreasing along a transition zone between the unblocked zone and the blocked zone; selectively enlarging the cross-web slot height profile;
including methods.
(Appendix 17)
The height profile along the unobstructed zone of the applicator slot is such that the height profile along the unobstructed zone of the applicator slot is such that the height profile along the unobstructed zone of the applicator slot 17. The method of claim 16, converging to a height profile average over the zone.
(Appendix 18)
It is a slot die,
an applicator slot extending along the width of the slot die and in fluid communication with a fluid flow path through the slot die;
at least one of the group consisting of a choker bar and a flexible die lip;
a force application mechanism operably coupled to the choker bar or flexible die lip;
a slot die including;
a controller configured to set the position of each actuator and operate the slot die according to one of a plurality of individual settings, the controller configured to operate the slot die using the force application mechanism. , configured to manipulate the shape of the choker bar or the flexible die lip by applying a force generally parallel to the width of the slot die;
system.
(Appendix 19)
It is a slot die,
an applicator slot extending along the width of the slot die and in fluid communication with a fluid flow path through the slot die;
a choker bar or flexible die lip extending along the width of the slot die;
a plurality of actuators spaced along the choker bar or flexible die lip, each actuator at a respective position for providing localized adjustment of fluid flow through the applicator slot; a plurality of actuators operable to adjust the height of the applicator slot;
one or more deckles that block a portion of the applicator slot to reduce the effective width of the applicator slot;
a slot die including;
Manipulating the shape of the choker bar or the flexible die lip by applying a force using the plurality of actuators to obtain a target cross-web slot height profile, where the actuators are connected to the applicator slot. fixed above the blocked zone of said applicator slot, dynamic above the unblocked zone of said applicator slot, and in a transition zone between said unblocked zone and said blocked zone. a controller configured to use the plurality of actuators to selectively expand the cross-web slot height profile along an unobstructed zone of the applicator slot, with decreasing degrees of expansion along the ,
A system equipped with.

Claims (19)

A method of operating a slot die, the slot die comprising: an applicator slot extending along a width of the slot die, the applicator slot being in fluid communication with a fluid flow path through the slot die; at least one of the group consisting of a choker bar and a flexible die lip, the method comprising:
manipulating the shape of the choker bar or the flexible die lip by applying a force generally parallel to the width of the slot die using a force application mechanism;
Method. 2. The method of claim 1, wherein the force generally parallel to the width of the slot die expands the flexible die lip or metal of the choker bar. 3. The method of claim 1 or 2, wherein the force generally parallel to the width of the slot die is selected to create a pressure relief shape. The slot die further includes the choker bar, the slot die further includes a plurality of actuators spaced apart along the width of the slot die, and the plurality of actuators extend along the width of the choker bar. each actuator is engaged with the choker bar, each actuator controlling the height of the fluid flow path at each actuator location by providing local adjustment of the choker bar position within the fluid flow path; A method according to any one of claims 1 to 3, operable as in any one of claims 1 to 3. The slot die further includes a plurality of actuators spaced apart along the width of the slot die, each actuator of the plurality of actuators for providing localized adjustment of fluid flow through the applicator slot. 5. A method according to any preceding claim, wherein the method is operable to adjust the height of the applicator slot at a respective position of each actuator. The slot die further includes the flexible die lip on one side of the applicator slot, and the plurality of actuators control the height of the applicator slot by moving the flexible die lip. 6. The method of claim 5, wherein the method is operable to: 7. The method of claim 6, wherein the flexible die lip includes a plurality of notches that facilitate locally bending the choker bar or flexible die lip. A method according to any preceding claim, wherein the force generally parallel to the width of the slot die either contracts or expands the metal forming the flexible die lip. . grinding the slot die while applying the force generally parallel to the width of the slot die;
removing the force generally parallel to the width of the slot die so that the slot die assumes a pressure-reduced configuration after grinding the slot die;
The method according to any one of claims 1 to 8, further comprising: A method according to any one of the preceding claims, wherein the force application mechanism comprises a heating element, a piezoelectric device, a mechanical device, a shoulder bolt element, a pneumatic device, or a hydraulic device. A method of operating a slot die, the slot die comprising: an applicator slot extending along a width of the slot die, the applicator slot being in fluid communication with a fluid flow path through the slot die; at least one of the group consisting of a choker bar and a flexible die lip; and a plurality of actuators spaced apart along the width of the slot die, each actuator of the plurality of actuators passing through the applicator slot. a plurality of actuators operable to adjust the height of the fluid flow path at a respective position of each actuator to provide localized adjustment of fluid flow, the method comprising:
locally expanding or contracting the choker bar or the flexible die lip of the slot die along a direction generally parallel to the width of the slot die, thereby causing the plurality of actuators to expand or contract the choker bar or the flexible die lip of the slot die; determining an actuator setting to adjust the cross-web slot height profile when engaging the gender die lip;
engaging the plurality of actuators with the choker bar or the flexible die lip based on the determined actuator settings;
including methods. 12. The choker bar or flexible die lip includes a plurality of notches extending generally parallel to a fluid flow direction to facilitate locally bending the choker bar or flexible die lip. The method described in. A method of operating a slot die, the slot die comprising: an applicator slot extending along a width of the slot die, the applicator slot being in fluid communication with a fluid flow path through the slot die; at least one of the group consisting of a choker bar and a flexible die lip; and a plurality of actuators spaced apart along the width of the slot die, each actuator of the plurality of actuators passing through the applicator slot. a plurality of actuators operable to adjust the height of the fluid flow path at a respective position of each actuator to provide localized adjustment of fluid flow, the method comprising:
blocking a portion of the applicator slot with a deckle to reduce the effective width of the applicator slot;
using a controller to predict the set of personalized settings from a plurality of personalized settings based on a preselected cross-web slot height profile of an unobstructed zone of the applicator slot, the prediction comprising: , based on a known correlation between the set of personalized settings and a cross-web slot height profile of the extrudate;
setting the position of each actuator according to the set of predicted individual settings for the adjustment of the slot die;
including;
the actuator is fixed over the blocked zone of the applicator slot and dynamic over the unblocked zone of the applicator slot during operation of the slot die;
Method. The height profile along the unobstructed zone of the applicator slot is such that the height profile along the unobstructed zone of the applicator slot is such that the height profile along the unobstructed zone of the applicator slot 14. The method of claim 13, converging to a height profile average over the zone. 1. A method of manufacturing an extruded article, the method comprising:
operating a slot die according to the method according to any one of claims 1 to 14 and extruding an extrudate through the applicator slot of the slot die to obtain the extruded article;
including methods. A method of purging a slot die, the slot die comprising: an applicator slot extending along a width of the slot die, the applicator slot being in fluid communication with a fluid flow path through the slot die; a choker bar or flexible die lip extending along the width of the slot die; and a plurality of actuators spaced apart along the choker bar or flexible die lip, each actuator controlling fluid flow through the applicator slot. a plurality of actuators, each actuator being operable to adjust the height of the applicator slot at a respective location to provide localized adjustment of the applicator slot; one or more deckles that reduce the effective width of the applicator slot, the method comprising:
manipulating the shape of the choker bar or the flexible die lip by applying a force using the plurality of actuators to obtain a target cross-web slot height profile; fixed above the blocked zone of the applicator slot and dynamic above the unblocked zone of the applicator slot;
the plurality of actuators along the unblocked zone of the applicator slot, with the degree of expansion decreasing along a transition zone between the unblocked zone and the blocked zone; selectively enlarging the cross-web slot height profile;
including methods. The height profile along the unobstructed zone of the applicator slot is such that the height profile along the unobstructed zone of the applicator slot is such that the height profile along the unobstructed zone of the applicator slot 17. The method of claim 16, converging to a height profile average over the zone. It is a slot die,
an applicator slot extending along the width of the slot die and in fluid communication with a fluid flow path through the slot die;
at least one of the group consisting of a choker bar and a flexible die lip;
a force application mechanism operably coupled to the choker bar or flexible die lip;
a slot die including;
a controller configured to set the position of each actuator and operate the slot die according to one of a plurality of individual settings, the controller configured to operate the slot die using the force application mechanism. , configured to manipulate the shape of the choker bar or the flexible die lip by applying a force generally parallel to the width of the slot die;
system. It is a slot die,
an applicator slot extending along the width of the slot die and in fluid communication with a fluid flow path through the slot die;
a choker bar or flexible die lip extending along the width of the slot die;
a plurality of actuators spaced along the choker bar or flexible die lip, each actuator at a respective position for providing localized adjustment of fluid flow through the applicator slot; a plurality of actuators operable to adjust the height of the applicator slot;
one or more deckles that block a portion of the applicator slot to reduce the effective width of the applicator slot;
a slot die including;
Manipulating the shape of the choker bar or the flexible die lip by applying a force using the plurality of actuators to obtain a target cross-web slot height profile, where the actuators are connected to the applicator slot. fixed above the blocked zone of said applicator slot, dynamic above the unblocked zone of said applicator slot, and in a transition zone between said unblocked zone and said blocked zone. a controller configured to use the plurality of actuators to selectively expand the cross-web slot height profile along an unobstructed zone of the applicator slot, with decreasing degrees of expansion along the ,
A system equipped with.

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