EP4259414A1 - Procédé et système de réglage de filière en forme de fente utilisée pour la fabrication d'un article extrudé - Google Patents
Procédé et système de réglage de filière en forme de fente utilisée pour la fabrication d'un article extrudéInfo
- Publication number
- EP4259414A1 EP4259414A1 EP20828126.1A EP20828126A EP4259414A1 EP 4259414 A1 EP4259414 A1 EP 4259414A1 EP 20828126 A EP20828126 A EP 20828126A EP 4259414 A1 EP4259414 A1 EP 4259414A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- slot
- die
- applicator
- slot die
- width
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 107
- 239000012530 fluid Substances 0.000 claims abstract description 156
- 230000007246 mechanism Effects 0.000 claims abstract description 38
- 238000004891 communication Methods 0.000 claims abstract description 24
- 238000010926 purge Methods 0.000 claims abstract description 19
- 230000007704 transition Effects 0.000 claims description 11
- 239000002184 metal Substances 0.000 claims description 9
- 230000000116 mitigating effect Effects 0.000 claims description 8
- 230000000903 blocking effect Effects 0.000 claims description 6
- 238000000227 grinding Methods 0.000 claims description 5
- 230000000712 assembly Effects 0.000 description 68
- 238000000429 assembly Methods 0.000 description 68
- 238000000576 coating method Methods 0.000 description 48
- 239000011248 coating agent Substances 0.000 description 46
- 238000001125 extrusion Methods 0.000 description 23
- 239000000463 material Substances 0.000 description 18
- 238000005259 measurement Methods 0.000 description 18
- 230000008859 change Effects 0.000 description 16
- 239000010408 film Substances 0.000 description 15
- 230000008569 process Effects 0.000 description 14
- 230000000694 effects Effects 0.000 description 9
- 239000002904 solvent Substances 0.000 description 8
- 238000012545 processing Methods 0.000 description 6
- 239000000853 adhesive Substances 0.000 description 5
- 230000001070 adhesive effect Effects 0.000 description 5
- 230000006870 function Effects 0.000 description 5
- 238000009474 hot melt extrusion Methods 0.000 description 5
- 230000010076 replication Effects 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 230000008602 contraction Effects 0.000 description 4
- 238000012546 transfer Methods 0.000 description 4
- 238000004458 analytical method Methods 0.000 description 3
- 238000007765 extrusion coating Methods 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 230000007935 neutral effect Effects 0.000 description 3
- 238000009420 retrofitting Methods 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 238000005452 bending Methods 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000010291 electrical method Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 230000003993 interaction Effects 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 210000003205 muscle Anatomy 0.000 description 2
- 230000010355 oscillation Effects 0.000 description 2
- 230000000737 periodic effect Effects 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 239000002356 single layer Substances 0.000 description 2
- 238000007764 slot die coating Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 230000003213 activating effect Effects 0.000 description 1
- 238000003491 array Methods 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 239000003085 diluting agent Substances 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 239000000499 gel Substances 0.000 description 1
- 229910000078 germane Inorganic materials 0.000 description 1
- 239000012943 hotmelt Substances 0.000 description 1
- 238000012804 iterative process Methods 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 239000011344 liquid material Substances 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 238000004881 precipitation hardening Methods 0.000 description 1
- 238000007639 printing Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 238000000518 rheometry Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
- B29C48/07—Flat, e.g. panels
- B29C48/08—Flat, e.g. panels flexible, e.g. films
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05C5/00—Apparatus in which liquid or other fluent material is projected, poured or allowed to flow on to the surface of the work
- B05C5/02—Apparatus in which liquid or other fluent material is projected, poured or allowed to flow on to the surface of the work the liquid or other fluent material being discharged through an outlet orifice by pressure, e.g. from an outlet device in contact or almost in contact, with the work
- B05C5/0254—Coating heads with slot-shaped outlet
- B05C5/0262—Coating heads with slot-shaped outlet adjustable in width, i.e. having lips movable relative to each other in order to modify the slot width, e.g. to close it
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/30—Extrusion nozzles or dies
- B29C48/305—Extrusion nozzles or dies having a wide opening, e.g. for forming sheets
- B29C48/31—Extrusion nozzles or dies having a wide opening, e.g. for forming sheets being adjustable, i.e. having adjustable exit sections
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/92—Measuring, controlling or regulating
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C2948/00—Indexing scheme relating to extrusion moulding
- B29C2948/92—Measuring, controlling or regulating
- B29C2948/92009—Measured parameter
- B29C2948/92114—Dimensions
- B29C2948/92133—Width or height
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C2948/00—Indexing scheme relating to extrusion moulding
- B29C2948/92—Measuring, controlling or regulating
- B29C2948/92009—Measured parameter
- B29C2948/92114—Dimensions
- B29C2948/92152—Thickness
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C2948/00—Indexing scheme relating to extrusion moulding
- B29C2948/92—Measuring, controlling or regulating
- B29C2948/92504—Controlled parameter
- B29C2948/92609—Dimensions
- B29C2948/92628—Width or height
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C2948/00—Indexing scheme relating to extrusion moulding
- B29C2948/92—Measuring, controlling or regulating
- B29C2948/92504—Controlled parameter
- B29C2948/92609—Dimensions
- B29C2948/92647—Thickness
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C2948/00—Indexing scheme relating to extrusion moulding
- B29C2948/92—Measuring, controlling or regulating
- B29C2948/92819—Location or phase of control
- B29C2948/92857—Extrusion unit
- B29C2948/92904—Die; Nozzle zone
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C2948/00—Indexing scheme relating to extrusion moulding
- B29C2948/92—Measuring, controlling or regulating
- B29C2948/92819—Location or phase of control
- B29C2948/92942—Moulded article
Definitions
- the invention relates to slot dies, along with assemblies, systems, and methods related thereof.
- slot dies include die lips that form 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.
- width refers to the cross-web (or cross-roller) dimension of a slot die and its components.
- an applicator slot of a slot die extends along the width of the slot die.
- Slot dies are commonly used to form extrusions, coatings, and other extruded articles.
- slot dies can be used in slot die coatings to apply a liquid material to a moving flexible substrate or “web.”
- coating materials can be at room temperature or a controlled temperature. When a coating material temperature is elevated to ensure that the coating material is melted or liquefied for processing, this is often referred to as “hot melt” coating.
- a coating material can include solvent diluents.
- Solvents can be water, organic solvents, or any suitable fluid that dissolves or disperses components of a coating. Solvents are typically removed in subsequent processing such as by drying.
- a coating can include single or multiple layers, and some slot dies may be used to apply multiple layers simultaneously.
- a coating can be a continuous coating across the width of the die or instead be comprised of strips, with each strip extending across only a portion of the width of the die and being separated from adjacent strips.
- extrusions are also used to form extrusions, including thin-film extrusions or other extrusions.
- extrusions can be extrusion coatings and applied to a web substrate, a process which may be referred to as extrusion coating.
- the extruded material forms a film or web directly.
- An extruded film might be subsequently processed by length orienting or tentering operations.
- the extrudate might comprise a single layer or multiple layers.
- a slot die can include 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.
- a slot die can also include a flexible die lip that can be used to adjust the local height of the applicator slot (or “slot height”) to control the flow rate of the extrudate from the applicator slot to provide a desired extrudate thickness profile.
- a slot die may include a plurality of actuators spaced along the width of the applicator slot in order to manipulate the thickness profile.
- each actuator can be configured to provide a local positional adjustment of a choker bar or flexible die lip.
- the cross-web profile of an extrudate can be measured.
- Each actuator may then need to be individually adjusted to provide a desired thickness profile, such as a uniform thickness, for the extrudate across the width of the applicator slot.
- This disclosure includes techniques for manipulating die lip or choker bar shape by applying forces that are generally parallel to the width of the die and where the associated force application mechanism is largely contained within the flexible die lip or restrictor/choker bar.
- Such forces parallel to the width of the die can be provided by an omni-directional expansion or contraction such as caused by localized heating or cooling of the die lip or choker bar.
- the flatness of a die lip can be manipulated by expanding the metal near the die lip, which causes the shape of the die lip to change between the discrete control points. This technique is analogous to the die having muscles that can flex between the positioning devices.
- a method for operating a slot die includes: an applicator slot extending along a width of the slot die, wherein the applicator slot is in fluid communication with a fluid flow path through the slot die, and at least one of a group consisting of a choker bar and a flexible die lip.
- the method comprises manipulating the choker bar or flexible die lip shape by applying, with a force application mechanism, forces that are generally parallel to the width of the die.
- a method for operating a slot die wherein the slot die includes: an applicator slot extending along a width of the slot die, wherein the applicator slot is in fluid communication with a fluid flow path through the slot die, at least one of a group consisting of: a choker bar and a flexible die lip, and a plurality of actuators spaced along the width of the slot die, wherein each actuator in the plurality of actuators is operable to adjust a height of the fluid flow path at its respective location to provide a local adjustment of fluid flow through the applicator slot, wherein the method comprises: determining a setting for a force application mechanism to locally expand or contract 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 adjusting a cross-web slot height profile where the force application mechanism engages with the choker bar or flexible die lip; and engaging the force application mechanism with the choker bar or the flexible die lip based on the determined setting.
- a method for operating a slot die includes: an applicator slot extending along a width of the slot die, wherein the applicator slot is in fluid communication with a fluid flow path through the slot die, at least one of a group consisting of: a choker bar and a flexible die lip, and a plurality of actuators spaced along the width of the slot die, wherein each actuator in the plurality of actuators is operable to adjust a height of the fluid flow path at its respective location to provide a local adjustment of fluid flow through the applicator slot, wherein the method comprises: blocking a portion of the applicator slot with a deckle to reduce an effective width of the applicator slot; predicting, with a controller, a set of discrete settings from a plurality of discrete settings based on a pre-selected cross-web slot height profile for an unblocked zone of the applicator slot, the prediction based on a known correlation between the set of discrete settings and a cross-web
- a method for making an extruded article comprising: operating a slot die according to an aforementioned method; and extruding through the applicator slot of the slot die an extrudate to obtain the extruded article.
- a method for purging a slot die includes: an applicator slot extending along a width of the slot die, wherein the applicator slot is in fluid communication with a fluid flow path through the slot die, a choker bar or a flexible die lip extending along the width of the slot die; a plurality of actuators spaced along the choker bar or a flexible die lip, each operable to adjust a height of the applicator slot at its respective location to provide a local adjustment of fluid flow through the applicator slot; and one or more deckles blocking a portion of the applicator slot to reduce an effective width of the applicator slot; wherein the method comprises manipulating the choker bar or the flexible die lip shape by applying forces with the plurality of actuators to obtain a target cross-web slot height profile, the actuators being fixed over a blocked zone of the applicator slot and being dynamic over an unblocked zone of the applicator slot; and selectively enlarging the cross-web slot height profile along
- a system comprising: a slot die including an applicator slot extending along a width of the slot die, wherein the applicator slot is in fluid communication with a fluid flow path through the slot die, and at least one of a group consisting of: a choker bar and a flexible die lip, and a force application mechanism operatively coupled to the choker bar or flexible die lip; and a controller configured to set a position of each actuator according to one of a plurality of discrete settings to operate the slot die, wherein the controller is configured to manipulate the choker bar or the flexible die lip shape by applying, with the force application mechanism, forces that are generally parallel to the width of the slot die.
- a system comprising a slot die and a controller
- the slot die includes an applicator slot extending along a width of the slot die, wherein the applicator slot is in fluid communication with a fluid flow path through the slot die, a choker bar or a flexible die lip extending along the width of the slot die; a plurality of actuators spaced along the choker bar or a flexible die lip, each operable to adjust a height of the applicator slot at its respective location to provide a local adjustment of fluid flow through the applicator slot; and one or more deckles blocking a portion of the applicator slot to reduce an effective width of the applicator slot.
- the controller is configured to manipulate the choker bar or the flexible die lip shape by applying forces with the plurality of actuators to obtain a target cross-web slot height profile, wherein the actuators are fixed over a blocked zone of the applicator slot and dynamic over an unblocked zone of the applicator slot; and selectively enlarge the cross-web slot height profile along an unblocked zone of the applicator slot with the plurality of actuators, while tapering down the degree of enlargement along a transition zone between the unblocked zone and the blocked zone.
- FIGS. 1 A-1B illustrate a slot die including a choker bar with a plurality of actuators, each actuator operable to adjust a height of the fluid flow path at its location.
- FIG. 2 illustrates a slot die including an adjustable rotary rod with a plurality of actuators connected to the rotary rod, each actuator operable to adjust the local position of the rotary rod at its location and thereby adjust the local height of the applicator slot.
- FIG. 3 illustrates a slot die including a flexible die lip with a plurality of actuators connected to the flexible die lip, each actuator operable to adjust the local position of the flexible die lip at its location and thereby adjust the local height of the applicator slot.
- FIG. 4 illustrates an actuator assembly including a position sensor and a controller for selecting the position of the actuator assembly based on the output of the position sensor.
- FIG. 5 is a flowchart illustrating techniques for selecting the position of each actuator in a plurality of actuators of a slot die according to a preselected cross-web profile of the extrudate.
- FIG. 6 is a flowchart illustrating techniques for selecting the position of each actuator in a plurality of actuators of a slot die according to a preselected die cavity pressure during operation of the die.
- FIG. 7 is a flowchart illustrating techniques for purging a slot die by increase the height of the fluid flow path adjacent each of the actuators while continuing to operate the die.
- FIG. 8 is a flowchart illustrating techniques for purging a slot die by substantially closing fluid flow path adjacent each of the actuators while continuing to operate the die.
- FIG. 9 illustrates a strip coating including a pattern created by repeatedly adjusting actuator position settings in a slot die.
- FIG. 10 illustrates an extrudate including a pattern created by repeatedly adjusting actuator position settings in a slot die.
- FIGS. 11 A-l ID illustrate an example of a user interface for a slot die controller.
- FIG. 12 illustrates techniques retrofitting a slot die with a set of actuator assemblies.
- FIGS. 13-22 relate to techniques for manipulating die lip shape by applying forces that are generally parallel to the width of the die and where the force application mechanism is largely contained within the flexible die lip or restrictor/choker bar in accordance with the techniques disclosed herein.
- the terms “preferred” and “preferably” refer to embodiments described herein that can afford certain benefits, 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 does not imply that other embodiments are not useful and is not intended to exclude other embodiments from the scope of the invention. As used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a” or “the” component may include one or more of the components and equivalents thereof known to those skilled in the art. Further, the term “and/or” means one or all of the listed elements or a combination of any two or more of the listed elements.
- FIGS. 1A and IB illustrate a slot die 10.
- Slot die 10 includes an upper die block 2 and a lower die block 3.
- Upper die block 2 combines with lower die block 3 to form a fluid flow path through slot die 10.
- the fluid flow path includes entry 5, die cavity 4 and applicator slot 6.
- Applicator slot 6 is between rotary rod 12, which is mounted to upper die block 2, and die lip 13 of lower die block 3. Because slot die 10 includes rotary rod 12 at its applicator slot, slot die 10 may be referred to as a rotary rod die.
- Slot die 10 includes a choker bar 11 that extends across the width of the fluid flow path within slot die 10.
- the width of the fluid flow path within slot die 10 at choker bar 11 may be approximately the same as the width of applicator slot 6 such that choker bar 11 extends along the width of applicator slot 6.
- Actuator assemblies 200 are mounted on a common mounting bracket 9 and spaced along the width of slot die 10.
- mounting bracket 9 may be segmented, e.g., mounting bracket 9 may include separate structures for each actuator assembly 200.
- Each actuator assembly 200 is operable to adjust a height of the fluid flow path at its respective location along the width of slot die
- an extrudate enters slot die 10 at fluid flow path entry 5 and continues through the fluid flow path of slot die 10, including die cavity 4 until the extrudate exits through applicator slot 6 and is applied to moving roller 7.
- the extrudate may be applied to a moving web (not shown), in other examples, the extrudate may be applied directly to roller 7.
- the extrudate and web may be run over a series of rollers to allow the extrudate to cool.
- One or more additional processes may be performed to the extrudate downstream of roller 7. While not germane to this disclosure, such processes include, but are not limited to, stretching, coating, texturing, printing, cutting, rolling, and laminating.
- production release liners can be removed and release liners added, or one or more additional layers (such as a laminated transfer tape) can be added. Curing steps could also occur, such as exposure to e-beam, an oven, or an ultraviolet (UV) chamber.
- UV ultraviolet
- slot die 10 includes a set of actuator assemblies 200 mounted on a common mounting bracket 9. Five actuator assemblies 200 are shown, but different numbers of actuator assemblies are also possible. Each actuator assembly 200 is attached to, or otherwise engaged with, choker bar 11 and actuator assemblies 200 are spaced along a width of choker bar 11. Each of the actuators is operable to control the height of the fluid flow path at its location by providing a local adjustment of the position of choker bar 11 within the fluid flow path within slot die 10.
- each of actuator assemblies 200 can include a motor that drives a linear actuator.
- Each of actuator assemblies 200 can also include a precision sensor, such as a linear variable differential transformer (LVDT) or a linear encoder, that detects position movements of the output shaft of the linear actuator.
- LVDT linear variable differential transformer
- the output shafts of linear actuator assemblies 200 are spaced along the width of choker bar
- each linear actuator assembly 200 is operable to adjust the local position of the choker bar.
- the positions of each linear actuator are individually selectable to provide a desired cross-web profile of an extrudate.
- the positions of linear actuator assemblies 200 can be precisely coordinated to provide a desired die cavity pressure within die cavity 4 during the operation of slot die 10 by adjusting the overall cross-sectional area of the fluid flow path adjacent to the choker bar 11 within slot die 10.
- the positions of each actuator assembly 200 may be actively controlled to create an extrudate with patterned features, such as repeating or random patterned features.
- references to the position of an actuator or actuator assembly are intended to more specifically refer to the relative positioning of the actuator output shaft.
- FIG. 2 illustrates slot die 20.
- Slot die 20 includes adjustable rotary rod 22 with a plurality of actuator assemblies 200 connected to rotary rod 22.
- Each actuator assembly 200 is operable to adjust the local position of rotary rod 22 at its location and thereby adjust the local height of applicator slot 6.
- Some aspects of slot die 20 are similar to those of slot die 10 and are discussed in limited detail with respect to slot die 20.
- Components of slot die 20 that have the same reference numeral as components in slot die 10 are substantially similar to the like-numbered component of slot die 10.
- Slot die 20 includes an upper die block 2 and a lower die block 3. Upper die block 2 combines with lower die block 3 to form a fluid flow path through slot die 20. The fluid flow path includes entry 5, die cavity 4 and applicator slot 6. Applicator slot 6 is between adjustable rotary rod 22, which is mounted to upper die block 2 and die lip 13 of lower die block 3. Because slot die 20 includes an adjustable rotary rod 22 at its applicator slot, slot die 20 may be referred to as a rotary rod die.
- Slot die 20 differs from slot die 10 in that the height of applicator slot 6 is controlled by actuator assemblies 200, which connect to rotary rod 22.
- Actuator assemblies 200 are mounted on a common mounting bracket 9 and spaced along the width of slot die 20.
- Each actuator assembly 200 is operable to adjust a height of the fluid flow path at its respective location along the width of slot die 20 to provide a local adjustment of fluid flow through applicator slot 6 by changing the position of rotary rod 22. While only one actuator assembly 200 is shown in FIG. 2, slot die 20 includes a set of actuator assemblies 200 spaced along the width of rotary rod 22 and slot die 20 and, similar to the arrangement of actuator assemblies 200 as shown in FIG. IB.
- an extrudate enters slot die 20 at fluid flow path entry 5 and continues through the fluid flow path of slot die 20, including die cavity 4, until the extrudate exits through applicator slot 6 and is applied to moving roller 7.
- the extrudate may be applied to a moving web (not shown), in other examples, the extrudate may be applied directly to roller 7.
- the extrudate and web may be run over a series of rollers to allow the extrudate to cool.
- One or more additional processes may be performed to the extrudate downstream of roller 7, as described above with respect to FIGS. 1 A and IB.
- Each of actuator assemblies 200 is operable to control the height of the fluid flow path at its location by providing a local adjustment of the position of rotary rod 22. As discussed in further detail below, the positions of each actuator assembly 200 are individually selectable to provide a desired cross-web profile of an extrudate. In addition, the positions of linear actuator assemblies 200 can be precisely coordinated to provide a desired die cavity pressure within die cavity 4 during the operation of slot die 20 by adjusting the overall cross-sectional area of applicator slot 6. In other examples, the positions of each actuator assembly 200 may be actively controlled to create an extrudate with patterned features, such as repeating or random patterned features.
- slot die 20 does not include a choker bar
- a slot die with an adjustable rotary rod may also include an adjustable choker bar, like choker bar 11 of slot die 10. The position of such a choker bar may be locally controlled by a set of actuators, just as with choker bar 11 of slot die 10.
- FIG. 3 illustrates slot die 30.
- Slot die 30 includes flexible die lip 32 with a plurality of actuator assemblies 200 connected to flexible die lip 32. Each actuator assembly 200 is operable to adjust the local position of flexible die lip 32 at its location and thereby adjust the local height of applicator slot 6.
- Some aspects of slot die 30 are similar to those of slot die 10 and slot die 20 and are discussed in limited detail with respect to slot die 30.
- Components of slot die 30 that have the same reference numeral as components in slot die 10 and slot die 20 are substantially similar to the like-numbered components of slot die 10 and slot die 20.
- Slot die 30 includes an upper die block 2 and a lower die block 3.
- Upper die block 2 combines with lower die block 3 to form a fluid flow path through slot die 30.
- the fluid flow path includes entry 5, die cavity 4 and applicator slot 6.
- Applicator slot 6 is between die lip 34, which is part of upper die block 2, and flexible die lip 32 of lower die block 3.
- Slot die 30 differs from slot die 10 in that the height of applicator slot 6 is controlled by actuator assemblies 200, which connect to flexible die lip 32.
- Actuator assemblies 200 are mounted on a common mounting bracket 9 and spaced along the width of slot die 30.
- Each actuator assembly 200 is operable to adjust a height of the fluid flow path at its respective location along the width of slot die 30 to provide a local adjustment of fluid flow through applicator slot 6 by changing the position of flexible die lip 32. While only one actuator 220 is shown in FIG. 3, slot die 30 includes a set of actuator assemblies 200 spaced along the width of flexible die lip 32and slot die 30 and, similar to the arrangement of actuator assemblies 200 as shown in FIG. IB.
- an extrudate enters slot die 30 under pressure at fluid flow path entry 5 and continues through the fluid flow path of slot die 30, including die cavity 4, until the extrudate exits through applicator slot 6 and is applied to moving roller 7.
- the extrudate may be applied to a moving web (not shown), in other examples, the extrudate may be applied directly to roller 7.
- the extrudate and web may be run over a series of rollers to allow the extrudate to cool.
- slot die 30 may be used with a different configuration of rollers.
- the extrudate may form a curtain that drops onto a downstream roller, in this case referred to as a casting wheel, that can be temperature controlled.
- an extrudate curtain may drop vertically or traverse horizontally (or any angle) into a nip of two rollers for subsequent processing. This is often used in both film extrusion and extrusion coating operations.
- One or more additional processes can be performed to the extrudate downstream of roller 7, as previously described with respect to FIGS. I A and IB.
- Each of actuator assemblies 200 is operable to control the height of the fluid flow path at its location by providing a local adjustment of the position of flexible die lip 32. As discussed in further detail below, the positions of each actuator assembly 200 are individually selectable to provide a desired cross-web profile of an extrudate. In addition, the positions of linear actuator assemblies 200 can be precisely coordinated to provide a desired die cavity pressure within die cavity 4 during the operation of slot die 30 by adjusting the overall cross-sectional area of applicator slot 6. In other examples, the positions of each actuator assembly 200 may be actively controlled to create an extrudate with patterned features, such as repeating or random patterned features.
- slot die 30 does not include a choker bar
- a slot die with a flexible die lip may also include an adjustable choker bar, like choker bar 11 of slot die 10. The position of such a choker bar may be locally controlled by a set of actuators, just as with choker bar 11 of slot die 10.
- FIG. 4 illustrates an assembly including actuator assembly 200, zero-backlash coupler 240 and controller 300.
- actuator assembly 200 may be used in a slot die to provide a local adjustment of a fluid flow path of the slot die, e.g., by adjusting the height of an applicator slot as with slot dies 20, 30 or by adjusting the height of a fluid flow path within the slot die as with slot die 10.
- Actuator assembly 200 includes motor 210, linear actuator 220, which is coupled to motor 210, and position sensor 230.
- motor 210 may be a stepper motor.
- the output shaft (not shown) of motor 210 is mechanically coupled to linear actuator 220.
- Sensor 230 senses the position of linear actuator 220.
- sensor 230 may be a LVDT sensor or a linear encoder.
- Sensor 230 is secured to output shaft 222 of linear actuator 220 with clamp 232 and precisely measures the relative position of output shaft 222 of linear actuator 220.
- the sensor 230 might measure the output coupler 240, die actuator linkage 252, flexible die lip 32, rotary rod 22, or choker bar 11.
- actuator assemblies that are suitable for use as actuator assemblies 200 are available from Honeywell International Incorporated of Morristown, New Jersey.
- Controller 300 receives position inputs from both motor 210 and sensor 230.
- motor 210 may be a stepper motor and may provide an indication of the number of “steps” the stepper motor has taken from a known reference position of the stepper motor.
- Sensor 230 may provide more precise position information to controller 300 than that provided by the motor 210.
- Controller 300 provides instructions to motor 210 to drive output shaft 222 of actuator 220 to a preselected position.
- controller 300 may monitor the position output shaft 222 of actuator 220 with sensor 230 while operating motor 210 in order to position output shaft 222 of actuator 220 according to a preselected position.
- controller 300 may control a set of actuator assemblies 200, either simultaneously or sequentially.
- controller 300 may control each of the actuator assemblies 200 in slot die 10, as shown in FIG. IB.
- Zero backlash coupler 240 in this example, includes two halves that screw together: bottom half 242 and top half 244. Bottom half 242 is directly attached to die actuator linkage 252 with a screw.
- zero backlash coupler 240 includes a stacked protrusion assembly that bolts onto the end of output shaft 222 of actuator 220.
- the stacked protrusion assembly includes two metallic discs 246 surrounding an insulative disc 248.
- insulative disc 248 may comprise a ceramic material.
- Bottom half 242 and top half 244 combine to encircle the stacked protrusion assembly, including metallic discs 246 and insulative disc 248, bolted onto the end of output shaft 222 of actuator 220. Once top half 244 is securely screwed to bottom 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.
- insulative disc 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 the damaging heat of a slot die.
- slot dies commonly operate at temperatures in excess of 300°F (149°C), whereas the components of actuator assembly 200, including motor 210 and sensor 230 may experience limited functionality or even permanent damage when subjected to temperatures to in excess of 130°F (54°C). For this reason, zero-backlash coupler 240 may function to keep the temperature of actuator assembly 200 at 130°F (54°C) or less.
- metallic discs 246 may also be formed from nonmetallic materials such that there is no metal-to- metal contact between output shaft 222 of actuator 220 and die actuator linkage 252. Such examples further thermally isolate actuator assembly 200 from the slot die housing.
- the surface area of the coupler 240 can be chosen to dissipate heat to keep the temperature of the actuator assembly 200 at 130°F (54°C) or less. This might be used independently or in combination with the insulative disc 248.
- active thermal control can be used cool to zero-backlash coupler 240, output shaft 222 or actuator assembly 200. Suitable examples of active thermal control include convective air flow, circulating liquid and thermo-electron devices.
- zero-backlash coupler 240 couples the output shaft 222 of actuator 220 to die actuator linkage 252 with limited or no backlash.
- zero-backlash coupler 240 may provide almost no backlash, such as less than ten micrometers, or even less than five micrometers, such as about three micrometers.
- the relatively large backlash of each differential bolt means that adjusting the position of one differential bolt may change the height of the fluid flow path at other bolts.
- slot dies 10, 20, 30 the position of output shaft 222 of actuator 220 directly corresponds to the local position of choker bar 11 (for slot die 10), rotary rod 22 (for slot die 20) and flexible die lip 32 (for slot die 30). For this reason, slot dies 10, 20 and 30 facilitate repeatable, precise positioning not available in slot dies utilizing differential bolts as actuation mechanisms.
- FIG. 5 is a flowchart illustrating techniques for selecting the position of each actuator in a plurality of actuators of a slot die according to a preselected cross-web profile of the extrudate. While not limited to the slot dies disclosed herein, for clarity, the techniques of FIG. 5 are described with respect to slot die 10 (FIGS. 1 A-1B), actuator assembly 200 (FIG. 4) and controller 300 (FIG. 4). In different examples, the techniques of FIG.
- a film slot die may be utilized for strip coating, a film slot die, a multilayer slot die, a hot melt extrusion coating die, a drop die, a rotary rod die, an adhesive slot die, a solvent coating slot die, a waterbased coating die, a slot fed knife die, an extrusion replication die, a vacuum contact die, or other slot die.
- a slot die such as slot die 10
- the slot die includes an applicator slot extending along a width of the slot die and a plurality of actuators spaced 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 in the plurality of actuators is operable to adjust a height of the fluid flow path at its respective location to provide a local adjustment of fluid flow through the applicator slot.
- a controller such as controller 300, in communication with each actuator is obtained (step 504).
- the controller is configured to set the position of each actuator according to one of a plurality of discrete settings, such as measured position of sensor 230 and/or a stepper motor setting for motor 210.
- controller 300 predicts a set of discrete settings from the plurality of discrete settings corresponding to a preselected cross-web profile (step 506).
- controller 300 may retrieve the preselected cross-web profile from a non-transitory computer readable medium or may receive the preselected cross-web profile from a user input.
- the predicted setting may correspond to measurements from sensor 230 and/or discrete positions settings for motor 210.
- Sensor 230 may provide more precise position information to controller 300 than that provided by the motor 210.
- controller 300 may predict settings for an actuator assembly 200 based on measurements from sensor 230 and may operate motor 210 to locate output shaft 222 according to the predicted setting rather than directly driving motor 210 to a number of steps corresponding to the predicted position.
- each actuator assembly including a measurement instrument, such as sensor 230
- each measurement instrument is configured to provide a local measurement of the slot die, the local measurement corresponding to the height of the fluid flow path at the location of the respective measurement instrument.
- a controller such as controller 300
- positions each of the actuators e.g., according to the set of discrete settings
- the controller may monitor the local measurements from the measurement instruments.
- the controller may then, for each of the actuators, adjusting the relative position of the actuator until the actuator provides the absolute height of the fluid flow path at the respective location of the actuator defined by the set of discrete settings.
- Fluid dynamics, fluid properties of the extrudate, and a digital model of a die allows controller 300 to predict discrete setting for the actuators of slot die 10. In many applications, it is desirable to provide a consistent thickness of an extrudate across the entire width of the die. As another example for strip coating controller may predict discrete setting for the actuators of slot die 10 to predict a set of discrete settings from the plurality of discrete settings corresponding to a preselected strip width.
- Modeling of an extrudate flowing through a die may incorporate many aspects of the die itself including applicator slot width, a distance from the manifold cavity to the exit of the applicator slot, and a slot height, which is the narrow dimension of the applicator slot between the two parallel surfaces defining the slot itself.
- One fundamental issue in attaining the uniformity of the flow, and critical uniformity of the coated product, is the ability to construct a die with the best possible uniformity of the die slot height. The sensitivity is greater than linear, which means that variations in slot height are magnified in extrudates.
- Modeling the flow may use of any appropriate models characterizing fluid rheology. For example, modeling the flow may include finite element analysis or may more directly rely on one or more equations. As one example, for a power law fluid, the relationship between flow in the slot and the slot geometry is given by the equation:
- Equation 1 Q/W is the flow per unit width, B is the slot height, P is pressure, L is the slot length (corresponding to the die width), n is the power law index and K is the coefficient for power law viscosity.
- slot uniformity can be characterized by the uniformity of the walls of the slot. If each slot has a Total Indicated Runout of 2t, then the percent uniformity of the flow from the slot is then:
- Equation 3 For a constant viscosity (Newtonian) fluid, this means that the coating uniformity goes as the cube of the slot height (B). This relationship is shown as Equation 3.
- Equation 3 may not be directly used to predict slot settings because Equation 3 may not account for all details including details related to the extrusion flows, materials, and to the die design itself. However, Equation 3 demonstrates the importance for providing a precisely tuned height across the width of the die. In particular, Equation 3 demonstrates that any variations in the height of the fluid flow path are magnified in the resulting crossweb profile of the extrudate.
- Equation 1 may, for example, be used to predict a die slot change because, according to the techniques disclosed herein, the position of the actuator, and by inference the slot height B, is known in combination with the desired extrudate target thickness, the current measured extrudate thickness. Previously, knowing the absolute position of the slot height during an extrusion process has not be possible, e.g., due to the backlash in differential bolts. Using the known target extrudate thickness and the measured extrudate thickness profile, Equation 1 can predict an appropriate die slot change. For example, as we know by inference the relationship between slot height profile and extrudate thickness profile from the known slot height profile and the measured extrudate thickness profile and can thus predict a slot height profile that would obtain the target thickness profile.
- Equation 4 For a more generalized Power Law fluid, Equation 4 may be represented as Equation 5.
- the fluid mechanical predictions can include the geometric circumstances of the die.
- the slot height may be better approximated by considering converging or diverging slots with a nominal fixed slot at the hinge point. Assuming the hinge point slot remains constant, then Equation 6 applies.
- Equation 9 represents Ci for Equation 8.
- Equation 9 (Equation 9) These closed form examples are useful, but it is clear that one may extend the model to include every conceived detail of the mechanical, thermal, and fluid dynamical process details. The better the predictive model, the more rapid the techniques disclosed herein will converge to the best operating condition for the desired extrudate profile.
- Equations 1-9 are merely exemplary, and any number of equations may be used to predict the settings for actuator assemblies 200 in slot die 10 corresponding to a preselected cross-web profile.
- predicting the optimal settings for actuator assemblies 200 in slot die 10 may include modeling heat transfer and thermal dissipation throughout slot die 10 and the extrudate.
- Such predictive modeling may include prediction of the mechanical deflections of the die assembly and mechanical elements due to thermal and flow induced forces.
- such models may rely upon finite element analysis, or may use more general equations to predict the settings for actuator assemblies 200 in slot die 10 corresponding to the preselected cross-web profile.
- slot die 10 is operated by passing an extrudate through the fluid flow path and out applicator slot 6 with the actuator assemblies 200 positioned according to the set of predicted settings (step 508).
- 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 inputs from a sensor that directly measures thicknesses of the extrudate at multiple cross-web locations. As one example, a beta radiation thickness gauge may be used to measure the thicknesses of the extrudate during operation of a slot die. For strip coating, controller 300 may receive inputs from a sensor that directly measures strip width and/or thickness of individual strips.
- controller 300 determines whether adjustments to the predicted set of discrete settings may provide a crossweb profile of the extrudate after it exits the applicator slot that more closely matches the preselected cross-web profile.
- controller 300 determines that adjustments to the predicted set of discrete settings may provide a cross-web profile of the extrudate after it exits the applicator slot that more closely matches the preselected cross-web profile
- the controller predicts an improved set of discrete settings from the plurality of discrete settings corresponding to the preselected cross-web profile (step 512).
- controller 300 repositions the actuators according to the improved predicted set of discrete settings (step 514). Steps 510, 512 and 514 may be repeated until controller 300 determines that the predicted set of settings cannot be improved and/or at periodic intervals to maintain a desired cross-web profile.
- a set of discrete settings (step 514) can be saved as a recipe for future retrieval and use at a future time minutes, hours, or years later when similar materials, extrusion or coating properties, and processing conditions are required.
- FIG. 6 is a flowchart illustrating techniques for selecting the position of each actuator in a plurality of actuators of a slot die according to a preselected die cavity pressure. While not limited to the slot dies disclosed herein, for clarity, the techniques of FIG. 6 are described with respect to slot die 10 (FIGS. IA -IB), actuator assembly 200 (FIG. 4) and controller 300 (FIG. 4). In different examples, the techniques of FIG.
- a film slot die may be utilized for a film slot die, a multilayer slot die, a hot melt extrusion coating die, a drop die, a rotary rod die, an adhesive slot die, a solvent coating slot die, a water-based coating die, a slot fed knife die an extrusion replication die, a vacuum contact die, or other slot die.
- a slot die such as slot die 10
- the slot die includes an applicator slot extending along a width of the slot die and a plurality of actuators spaced 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 in the plurality of actuators is operable to adjust a height of the fluid flow path at its respective location to provide a local adjustment of fluid flow through the applicator slot.
- a controller such as controller 300, in communication with each actuator is obtained (step 604).
- the controller is configured to set the position of each actuator according to one of a plurality of discrete settings, such as measured position of sensor 230 and/or a stepper motor setting for motor 210.
- controller 300 predicts a set of discrete settings from the plurality of discrete settings corresponding to a preselected die cavity pressure (step 606).
- 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 a user input.
- the predicted setting may correspond to measurements from sensor 230 and/or discrete positions settings for motor 210. Sensor 230 may provide more precise position information to controller 300 than that provided by the motor 210. For this reason, controller may predict settings for an actuator assembly 200 based on measurements from sensor 230 and may operate motor 210 to locate output shaft 222 according to the predicted setting rather than directly driving motor 210 to a number of steps corresponding to the predicted position.
- Fluid dynamics known fluid properties of the extrudate, and a digital model of a die allows controller 300 to predict discrete setting for the actuators of slot die 10.
- Modeling of an extrudate flowing through a die may incorporate many aspects of the die itself including applicator slot width, a distance from the manifold cavity to the exit of the applicator slot, and a slot height, which is the narrow dimension of the applicator slot between the two parallel surfaces defining the slot itself.
- predicting the optimal settings for actuator assemblies 200 in slot die 10 may include modeling heat transfer and thermal dissipation throughout slot die 10 and the extrudate. As previously mentioned, such models may rely upon finite element analysis, or may use more general equations to predict the settings for actuator assemblies 200 in slot die 10 corresponding to the preselected die cavity pressure.
- slot die 10 is operated by passing an extrudate through the fluid flow path and out applicator slot 6 with the actuator assemblies 200 positioned according to the set of predicted settings (step 608).
- controller 300 measures the die cavity pressure within die cavity 4 (step 610) or at a suitable measurement point in flow path, which may occur before or after fluid flow path entry 5. For example, controller 300 may receive inputs from a sensor that directly measures die cavity pressure within die cavity 4. Using the measured die cavity pressure, fluid dynamics and the digital model of the die, controller 300 then determines whether adjustments to the predicted set of discrete settings may provide a die cavity pressure that more closely matches the preselected die cavity pressure. If controller 300 determines that adjustments to the predicted set of discrete settings may provide a die cavity pressure that more closely matches the preselected die cavity pressure, the controller predicts an improved set of discrete settings from the plurality of discrete settings corresponding to the preselected die cavity pressure (step 612).
- controller 300 While continuing to operate the slot die by passing the extrudate through the fluid flow path and out the applicator slot, controller 300 repositions the actuators according to the improved predicted set of discrete settings (step 614). Steps 610, 612 and 614 may be repeated until controller 300 determines that the predicted set of settings cannot be improved and/or at periodic intervals to maintain a desired die cavity pressure.
- controller 300 may seek to provide a cross-web profile with a consistent slot height, while also maintaining a preselected die cavity pressure.
- controller 300 may use the same fluid dynamics and a digital model of the die discussed with respect to FIG. 5 and FIG. 6 to determine settings for actuator assemblies 200 that will provide both a certain cross-web profile and a preselected die cavity pressure.
- the pressure control enables control of a die arranged to coat strips or precise width. Further, the pressure control can be accomplished where a sensor to detect strip width in communication with controller 300 is utilized to select the die pressure control.
- a set of discrete settings (step 514) can be saved as a recipe for future retrieval and used at a future time that could be minutes, hours, or years later when similar materials, extrusion or coating properties, and processing conditions are required.
- FIG. 7 is a flowchart illustrating techniques 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. While not limited to the slot dies disclosed herein, for clarity, the techniques of FIG. 7 are described with respect to slot die 10 (FIGS. 1 A, IB), actuator assembly 200 (FIG. 4) and controller 300 (FIG. 4). In different examples, the techniques of FIG. 7 may be utilized for a film slot die, a multilayer slot die, a hot melt extrusion coating die, a drop die, a rotary rod die, an adhesive slot die, a solvent coating slot die, a water-based coating die, a slot fed knife die, an extrusion replication die, a vacuum contact die, or other slot die.
- a slot die such as slot die 10
- the slot die includes an applicator slot extending along a width of the slot die and a plurality of actuators spaced 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 in the plurality of actuators is operable to adjust a height of the fluid flow path at its respective location to provide a local adjustment of fluid flow through the applicator slot.
- a controller such as controller 300, in communication with each actuator is obtained (step 704).
- the controller is configured to set the position of each actuator according to one of a plurality of discrete settings, such as measured position of sensor 230 and/or a stepper motor setting for motor 210.
- Controller 300 positions each of the actuators with the controller according to a set of discrete settings selected from the plurality of discrete settings (step 706), and slot die 10 is operated by passing an extrudate through the fluid flow path and out applicator slot 6 with the actuator assemblies 200 positioned according to the set of discrete settings (step 708).
- any small disturbance to the flow in the die slot will result in a disruption to the flow of liquid emitted from the die slot, thus affecting the cross-web uniformity of the extrudate or coating.
- such disturbances are associated with gels or particulates getting caught in the die slot itself.
- this flow blockage results in a streak, or if wider, a band in the coating. In film extrusion, this results in undesirable die lines. For this reason, it is desirable to allow the impurity to pass through the die.
- controller 300 increases the height of the fluid flow path adjacent each of the actuator assemblies 200 while continuing to pass the extrudate through the fluid flow path and out the applicator slot (step 710).
- controller 300 may operate actuator assemblies 200 in unison or sequentially to increase the height of the fluid flow path through slot die 10.
- controller After increasing the height of the fluid flow path adjacent each of the actuators to allow the disturbance to clear the die, while continuing to pass the extrudate through the fluid flow path and out the applicator slot, controller repositions each of the actuators with the controller according to the original set of discrete settings, i.e., the most recent set of adjusted settings prior to the purge operation, to resume operating the slot die with the actuators positioned according to the original set of discrete settings (step 712).
- the repositioning of the actuators according to the original set of discrete settings may occur within thirty minutes, such as less than fifteen minutes, less than five minutes, less than two minutes or even less than one minute, of increasing the height of the fluid flow path adjacent the actuators.
- FIG. 8 is a flowchart illustrating techniques for purging a slot die by substantially closing the fluid flow path adjacent each of the actuators while continuing to operate the die. While not limited to the slot dies disclosed herein, for clarity, the techniques of FIG. 8 are described with respect to slot die 10 (FIGS. 1 A, IB), actuator assembly 200 (FIG. 4) and controller 300 (FIG. 4). In different examples, the techniques of FIG. 8 may be utilized for a film slot die, a multilayer slot die, a hot melt extrusion coating die, a drop die, a rotary rod die, an adhesive slot die, a solvent coating slot die, a water-based coating die, a slot fed knife die, an extrusion replication die, a vacuum contact die, or other slot die.
- a slot die such as slot die 10
- the slot die includes an applicator slot extending along a width of the slot die and a plurality of actuators spaced 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 in the plurality of actuators is operable to adjust a height of the fluid flow path at its respective location to provide a local adjustment of fluid flow through the applicator slot.
- a controller such as controller 300, in communication with each actuator is obtained (step 804).
- the controller is configured to set the position of each actuator according to one of a plurality of discrete settings, such as measured position of sensor 230 and/or a stepper motor setting for motor 210.
- Controller 300 positions positioning each of the actuators with the controller according to a set of discrete settings selected from the plurality of discrete settings, and slot die 10 is operated by passing an extrudate through the fluid flow path and out applicator slot 6 with the actuator assemblies 200 positioned according to the set of discrete settings (step 806).
- controller 300 decides to interrupt the extrusion process through slot die 10. Accordingly, controller 300 substantially closes the fluid flow path adjacent each of the actuator assemblies 200 (step 808). For example, controller 300 may operate actuator assemblies 200 in unison or sequentially to substantially the fluid flow path through slot die 10.
- a slot die such as slot die 10
- can include a purge valve (not shown in the figures).
- the extrudate may continue to flow through the slot die once by purging the extrudate from the purge valve while the fluid flow path is substantially closed (step 810).
- the purge valve may operate as a pressure relief valve and may open automatically once controller 300 substantially closes the fluid flow path adjacent each of the actuator assemblies 200 due to increased pressure within die cavity 4.
- the purge valve may be actively opened, either by controller 300 or an operator.
- controller 300 After substantially closing the fluid flow path adjacent each of the actuator assemblies 200, while continuing to purge the extrudate from the purge valve, once ready to resume operations, controller 300 repositions each of the actuators according to the original set of discrete settings (step 812). In addition, the purge valve is closed, either automatically or manually to resume operation of the slot die (step 814). In some examples, the repositioning of the actuators according to the original set of discrete settings to resume operating the slot die with the actuators positioned according to the set of discrete settings may occur within thirty minutes, such as less than fifteen minutes, less than five minutes, less than two minutes or even less than one minute, of substantially closing the fluid flow path.
- FIG. 9 illustrates a strip coating 900, which includes strips 904 that form a strip pattern created by repeatedly adjusting actuator position settings in a slot die. Strips 904 were extruded simultaneously from a single die, such as slot die 10 along direction 902. In particular, strip coating 900 provides strips 904 having varying widths.
- a slot die such as slot die 10 may be operated to produce strips 904 by positioning each of the actuators with the controller according to a first set of discrete settings selected from the plurality of discrete settings and by passing an extrudate through the fluid flow path and out the applicator slot with the actuators positioned according to the first set of discrete settings. Then, while passing the extrudate through the fluid flow path and out the applicator slot, controller 300 may change the positions of the actuators with the controller to create strips having varying widths.
- controller 300 may cycle between a series of sets of discrete settings including the first set of discrete settings such that the varying widths of strips 904 provide a substantially repeating pattern, such as that shown in FIG. 9. Controller 300 can continue to change the position of the actuators while passing the extrudate through the fluid flow path and out the applicator slot to create varying widths in the extrudate for a period in excess of ten minutes, such as a period in excess of thirty minutes, a period in excess of one hour, a period in excess of three hours or even a period in excess of twelve hours.
- FIG. 10 illustrates extrudate 910 including a pattern created by repeatedly adjusting actuator position settings in a slot die.
- Extrudate 910 was extruded from a die, such as slot die 10 along direction 912. As shown in FIG. 10, lighter sections represent relatively thicker portions of the patterned product and darker sections represent relatively thinner portions of the patterned product.
- extrudate 910 includes a series of ridges that extend at an angle across a width of extrudate 910.
- a slot die such as slot die 10, may be operated to produce extrudate 910 by positioning each of the actuators with the controller according to a first set of discrete settings selected from the plurality of discrete settings and by passing an extrudate through the fluid flow path and out the applicator slot with the actuators positioned according to the first set of discrete settings. Then, while passing the extrudate through the fluid flow path and out the applicator slot, controller 300 may change the positions of the actuators with the controller to create patterned features in the extrudate.
- controller 300 may selects randomized settings from the plurality of discrete settings such that the patterned features in the extrudate are randomized pattern features.
- the randomized settings selected by the controller conform to preselected specifications for the randomized pattern features, for example, such preselected specifications may represent an average extrudate thickness, a standard deviation of product thickness or other product profile specification.
- controller 300 may cycle between a series of sets of discrete settings including the first set of discrete settings such that the patterned features in the extrudate are a substantially repeating pattern, such as that shown in FIG. 10. Controller 300 may continue to change the position of the actuators while passing the extrudate through the fluid flow path and out the applicator slot to create patterned features in the extrudate for a period in excess of ten minutes, such as a period in excess of thirty minutes, a period in excess of one hour, a period in excess of three hours or even a period in excess of twelve hours. Controller 300 may retrieve the first set of discrete settings and preselected specifications for the pattern features from a non-transitory computer readable medium. In other examples, controller 300 may receive the first set of discrete settings and preselected specifications for the pattern features from a user input.
- FIGS. 11 A-l ID illustrate an example user interface 920 for a slot die controller.
- User interface 920 may interact with controller 300 to control operations of a set of actuator assemblies to control the operation of a slot die.
- user interface 920 includes indications of a selected slot die operation program 924, die temperature 926 and die pressure 928.
- User interface 920 also include a set of selectable buttons that control operations of the die as well as corresponding cancel button, which allow a user to cancel the selection of one of the selectable buttons in the event that a selectable button was inadvertently activated.
- Selectable button 930 is configured to initiate a purge operation, such as the techniques disclosed herein with respect to FIG. 8.
- Selectable button 932 is configured to initiate a slot-clearing operation, such as the techniques disclosed herein with respect to FIG. 7.
- Selectable button 934 is configured to resume operation of the slot die according to the previous settings after a purge operation or a slot-clearing operation.
- FIG. 11 A also illustrates profile tab 940.
- Selection of profile tab 940 displays a graph including an indication of an extrudate product profile measured across a width of the extrudate product. The chart also displays an actuator number relative to the width of the extrudate product.
- profile tab 940 includes a scroll bar 942, which may be used to view the extrudate product profile at different times. However, as shown in FIG. 11 A, scroll bar 942 is in the most forward position, such that profile tab 940 displays the current extrudate product profile and not a historical record of the extrudate product profile.
- FIG. 1 IB illustrates slot height tab 950.
- Selection of slot height tab 950 displays a graph including an indication of slot height across a width of the die. The chart also displays an actuator number relative to the width of the slot height.
- slot height tab 950 includes a scroll bar 952, which may be used to view the slot height at different times. However, as shown in FIG. HB , scroll bar 952 is in the most forward position, such that slot height tab 950 displays the current extrudate product profile and not a historical record of the extrudate product profile.
- Slot height tab 950 further includes selectable button, which may be used to save the current actuator settings for later retrieval.
- FIG 11C illustrates auto-select average setpoint tab 960.
- Auto-select average setpoint tab 960 displays a chart including 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 measured extrudate thickness by weight and height.
- auto-select average setpoint tab 960 includes a selectable update setpoint button 964. Selection of selectable update setpoint button 964 causes the controller to calculate new setpoints that will limit variability in the product profile. The new setpoints are then displayed in the chart of auto-select average setpoint tab 960. Selectable button 966 allows a user to then change the position of the actuators according to the calculated new setpoints.
- FIG. 1 ID illustrates auto-select pressure tab 970.
- Selection of auto-select pressure tab 970 displays a chart including 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 measured extrudate thickness by weight and height.
- auto-select pressure tab 970 includes a selectable update setpoint button 974. Selection of selectable update setpoint button 974 causes the controller to calculate new setpoints according to the pressure indicated in the “set new pressure box” 978. The new setpoints are then displayed in the chart of auto-select pressure tab 970. Selectable button 976 allows a user to then change the position of the actuators according to the calculated new setpoints.
- FIG. 12 illustrates techniques for retrofitting a slot die with actuator assemblies, such as a set of actuator assemblies 200 (FIG. 4).
- the techniques of FIG. 12 may be utilized for a film slot die, a multilayer slot die, a hot melt extrusion coating die, a drop die, a rotary rod die, an adhesive slot die, a solvent coating slot die, a water-based coating die, a slot fed knife die, an extrusion replication die, a vacuum contact die, or other slot die.
- a slot die is obtained (1202).
- the slot die includes an applicator slot extending along a width of the slot die and a plurality of actuation mechanisms spaced 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 in the plurality of actuation mechanisms is operable to adjust a height of the fluid flow path at its respective location to provide an adjustment of fluid flow through the applicator slot.
- the slot die may be operated using the plurality of actuation mechanisms to control a height of a fluid flow path across a width of the slot die.
- the actuation mechanisms include one or more of the following: thermally adjustable bolts, differential bolts, piezo-electric actuators, pneumatic actuators; and/or hydraulic actuators.
- the actuation mechanisms include thermally-adjustable bolts and the technique for retrofitting a slot die with thermally- adjustable bolts may include evaluating the cross-web profile of the extrudate after it exits the applicator slot and adjusting the relative position of one or more of the actuation mechanisms with its respective thermally-adjustable bolt such that the cross-web profile of the extrudate after it exits the applicator slot more closely conforms to a preselected crossweb profile.
- the applicator slot can be adjusted by applying a pressing load or tensile load to a flexible die lip using a lever supported by a rotating shaft as a fulcrum, along with an operating rod displaced in an axial direction by the body of the slot die.
- Rotational force of the lever is converted into a force in the axial direction of the operating rod, and the force in the axial direction becomes a pressing load or a tensile load exerted on the flexible die lip.
- the lever directly can apply a force to the operating rod at the point of action of the lever.
- thermally adjustable bolts automatically regulate the applicator slot using a plurality of adjusting pins, coupled to respective thermoelements disposed on a flexible die lip.
- the thermoelements can be controllable by the controller in to adjust the applicator slot through the action of mechanical force applied to the flexible die lip by the corresponding adjusting pin through expansion or contraction of the thermoelements.
- the actuation mechanism can include providing at least two adjusting pins and/or thermoelements that are simultaneously adjusted.
- the actuation mechanisms are removed from the die housing (1204).
- a plurality of actuator assemblies such as actuator assemblies 200, are installed in place of the actuation mechanisms (1206).
- Each actuator assembly in the plurality of actuator assemblies is operable to adjust a height of the fluid flow path at its respective location to provide a local adjustment of fluid flow through the applicator slot.
- a controller such as controller 300, is obtained 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 discrete settings, such as measured position of sensor 230 and/or a stepper motor setting for motor 210.
- controller 300 predict a set of discrete settings from the plurality of discrete settings corresponding to a preselected die cavity pressure.
- 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 a user input.
- the predicted setting may correspond to measurements from sensor 230 and/or discrete position settings for motor 210.
- Sensor 230 may provide more precise position information to controller 300 than that provided by the motor 210.
- controller may predict settings for an actuator assembly 200 based on measurements from sensor 230 and may operate motor 210 to locate output shaft 222 according to the predicted setting rather than directly driving motor 210 to a number of steps corresponding to the predicted position.
- Fluid dynamics known fluid properties of the extrudate, and a digital model of a die allows controller 300 to predict discrete settings for the actuator assemblies.
- Modeling of an extrudate flowing through a die may incorporate many aspect of the die itself including applicator slot width, a distance from the manifold cavity to the exit of the applicator slot, and a slot height, which is the narrow dimension of the applicator slot between the two parallel surfaces defining the slot itself.
- predicting settings for the actuator assemblies may include modeling heat transfer and thermal dissipation throughout the slot and the extrudate.
- FIGS. 13-20 illustrates techniques for manipulating die lip shape by applying forces that are generally parallel to the width of the die and where a force application mechanism is provided and largely contained within the flexible die lip or restrictor/choker bar in accordance with the techniques disclosed herein.
- Die lips can be manipulated by differential bolts, heated bolts, or piezoelectric devices.
- actuator assemblies such as actuator assemblies 200.
- these devices are intended to control the die lip globally by pushing or pulling at discrete locations.
- the pushing/pulling is done in a direction generally orthogonal to width of the die.
- the die lip shape is instead manipulated by applying forces that are generally parallel to the width of the die and where a force application mechanism is provided that is largely contained within the flexible die lip or restrictor/choker bar.
- the flatness of the die lip can be manipulated by expanding the metal near the die lip, which causes the shape of the die lip to change between the discrete control points, as shown in FIG. 13.
- This technique is analogous to the die having muscles that can flex between the positioning devices.
- the slot die profiles shown in FIG. 13 illustrate how varying amounts of expansion in the flexible die lip, with vertical notches (i.e., saw cuts) in the flexible die lip, can be quantified to enable precise tuning of slot die profile. An expanded version of this chart shall be visited later in FIG. 17.
- the provided techniques provide a force application mechanism that extends or reacts to enable localized deflection of the die lip or choker bar.
- Exemplary force application mechanisms include piezoelectric devices, heated elements, mechanical devices, pneumatic devices, and hydraulic devices.
- application of bolt torque via a shoulder bolt element is used to expand the metal in the vicinity of the threads and change the profile at the lip of the die.
- this shoulder bolt also serves as a spindle for actuator assemblies of the die, such as actuator assemblies 200.
- localized cooling or heating of the lip at points along the lip would contract the metal in the vicinity and change the profile at the die lip.
- the techniques disclosed herein can be used to create a coating die with a “built in” pressure mitigating shape such as by grinding the die with force elements that when removed and the die assembled, create the desired pressure mitigating shape.
- this same strategy can be used to simply create a “flat” die slot upon assembly of the die.
- the pressure mitigating shape can be based on pre-determined forces or actuator settings, either of which can be provided automatically, semi-automatically, or manually.
- the aforementioned pre-determined forces are parallel to the width of the slot die, and locally expand or contract the choker bar or flexible die lip parallel to the width of the slot die.
- the setting for the force application mechanism can be automatically determined, for instance, based on a target cross-web slot height profile average across the width of the slot die.
- any small disturbance to the flow in the die slot will result in a disruption to the flow of liquid emitted from the die slot, thus affecting the cross-web uniformity of the coating or extruded sheet.
- Extrusion dies typically have a flexible die lip so that the slot can be adjusted to improve the uniformity of the extruded film.
- Several techniques are used to flex the lip including differential bolts, thermal bolts, piezoelectric devices and actuators, as described previously. In all of these cases, the pushing/pulling is done in a direction generally orthogonal to width of the die. Spacing of the devices used to move the lip varies from around an inch (2.54 centimeters) to as much as 2.75 inches (7 centimeters). Between the devices, it is critical to have a smooth, continuous surface on the die lip since it is difficult to affect these interstitial areas by activating the movement devices. It is generally desirable to provide fine spatial resolution of extruded uniformity control.
- the spatial resolution is limited by the number of actuators that can be adjacently placed along the width of the die.
- the spatial resolution of the adjustable die e.g., flexible lip or choker bar types
- pressure deflection between the conventional adjustors is a fundamental limitation for all adjustable dies.
- To make the lip or choker bar adjustable it must be flexible.
- making the flexible lip or choker bar resist undesirable pressure deflection in the spans between adjusters requires making it stiffer — directly at odds with the need to make it adjustable.
- the die lip can remain more flexible, important to enable the extruded flow uniformity adjustment, while also directly mitigating the effects of pressure deflection between the conventional actuators.
- Force application mechanisms capable of pushing and pulling a flexible lip or choker bar are generally engaged with the lip or choker bar.
- This may be provided, for example, by a threaded connection.
- the threaded connection includes a shoulder bolt.
- lip profile can be manipulated by controlling the shoulder bolt torque. Tightening or torqueing the bolt causes the material around the threads to be compressed and when the expansion occurs near the lip, it can be used to change the die lip profile. This may be particularly useful when combined with actuator assemblies 200.
- the techniques of this disclosure may be used to create a coating die with a “built in” pressure-mitigating shape.
- Precision die lip adjustment can be done using several methods, including mechanical bolts which rely on threaded engagement, thermal bolts which locally heat the lip and adjust lip position via thermal expansion, piezoelectric devices which are moved electrically, actuators which use stepper motors to push the lip or combinations of these.
- the intent of the adjustment mechanism in all of these is to move the lip at discrete locations, which are aligned with the device, which are typically spaced from 2.5 cm to 7 cm apart.
- the shape of the die lip between the devices is uncontrolled but does react to the movement of the device, both with and without the effect of the die pressure.
- the shape of the die lip is intentionally manipulated by controlling the attachment of the pushing device.
- the spindle In the case of a mechanical actuator which pushes a spindle, the spindle is threaded into the die lip.
- thermal bolts and differential bolts singly or in combination with piezoelectric devices.
- FIG. 14 illustrates an enlarged view of a flexible die block 1300 with bolts 1302 serving as force application mechanisms attached to the flexible die lip 1304.
- This die was fabricated from a precipitation hardening stainless steel commonly referred to as 15-5 PH (obtained under the trade designation “UNS SI 5500” from Crucible Materials Corporation, Syracuse, NY).
- the bolts 1302 can connect to one or more actuator assemblies, such as actuator assemblies 200.
- the flexible die lip includes a plurality of regularly- spaced notches 1306 to facilitate bending of the flexible die lip 1304 as the metal expands.
- FIG. 15 illustrates an interferometer plot (using a laser interferometer provided by ZYGO Corporation, Middlefield, CT) of the die lip shown in FIG. 14 without the spindles attached to the die lip
- FIG. 16 illustrates an interferometer plot of the die lip shown in FIG. 14 with the spindles attached to the die lip.
- the dashed line represents a slot die parting line
- the downward pointing arrows in FIG. 16 show the actuator spindle locations.
- FIGS. 15 and 16 show the profile near the lip edge without spindles attached and FIG. 16 shows a similar plot with the spindles attached and torqued to 35 ft-lbs. (47 newton-meters). Data was collected using the interferometer, on the top die surface, near the slot exit.
- the torque applied to the threaded connection causes compressive stress in the material in the vicinity of the threads. This effectively “pushes away” from the threaded connection and causes the material between the positioning devices to effectively expand, therefore changing the profile between the positioning devices. Increasing the torque can increase this effect, as discussed below.
- the die shown in FIG. 13 has fifteen actuators and measurements were taken at each actuator as well as the mid and quarter points. Initially, the spindles were left loose and the die profile was measured. Then, the spindles were torqued to various levels. The profile is shown in FIG. 17.
- the vertical lines at integer positions on the plot represent the location of spindles and the amplitude each curve represents the variation between the actuators.
- the solid line labeled “Loose” represents the profile of the die lip without the spindles.
- Each of the other series in the plot represents increasing torque. It can be seen that the variation is increasing with the level of torque applied to the spindles.
- FIG. 18 shows the linear relationship between the variation between actuators and the applied torque.
- FIG. 18 plots the spindle torque relative to the average deviation between actuators and illustrates the effect of spindle torque on slot profile.
- FIG. 19 shows the lip profile for the test die shown in FIG. 14, with a representative cavity pressure applied.
- the variation between actuators is found to be around 77 millionths of an inch (i.e., 1.96 micrometers).
- the direction of the deflection is opposite of the direction of the deflection due to torque, which combines to make the die lip profile more uniform. So, based on the relationship between average deviation and torque shown in FIG. 18, one could choose 35 ft-lbs. (or 47 newton-meters) of torque on the spindles to exactly counteract the pressure induced die slot deflection.
- Differential thermal expansion can also be used to compensate for pressure induced die slot deflection.
- Table 1 below characterizes the oscillation of crossweb slot height profile at three locations along the applicator slot.
- the desired temperature for the die lip segment can be either higher or lower than that of the die, depending on the level of heat input. If the temperature in the vicinity of the die lip segment is lower than that of the remainder of the die, it is possible to invert the peaks and valleys observed in the cross-web slot height profile of the applicator slot. This is shown in FIG. 20.
- control of the die lip profile is described as being a function of the bolt torque.
- any method of applying a controlled expansion, or even contraction of the material in the vicinity of the die lip would be expected to have a similar effect. This could include mechanical, thermal or electrical methods.
- the example here implies expansion radially away from the axis of the spindle, but this could be in any direction, for example parallel to the die lip.
- the techniques disclosed herein can be used to create a coating die with a “built in” pressure mitigating shape such as by grinding the die with force elements (and associated forces) that when removed and the die assembled, create the desired pressure mitigating shape.
- fluid pressure normally deflects the die shape by 1.27 micrometers in the spans between actuators, but the required spindle torque with a shoulder bolt feature induces a deflection of 2.54 micrometers.
- the coating die can be ground with shoulder bolts at a lower torque level that, when removed, would result in a non-flat shape.
- the spindles with shoulder bolt feature are inserted and torqued to their specification, the desired 1.27 micrometer deflection mitigates the pressure effects, resulting in a desired flat shape.
- This strategy can also be used for die elements that do not include shoulder bolt spindle attachments for actuators. For example, if the actuator attachment does not induce the deflection as a shoulder bolt does, then elements could be added for use in the grinding process only to deflect the die lip or choker bar so that when they are removed, the lip includes the desired shape profile to resist pressure deflection.
- control of the die lip profile is described as being a function of the bolt torque.
- any method of applying a controlled expansion, or even contraction of the material in the vicinity of the die lip can have a similar effect.
- Useful force application mechanisms include mechanical, thermal or electrical methods, piezo electric devices, heated elements, mechanical devices, pneumatic devices, and hydraulic devices.
- expansion radially away from the axis of the spindle but this could be in any direction, for example parallel to the die lip.
- the techniques disclosed herein include the fabrication strategies to induce a desired flow slot shape, means suitable as a “die set-up” such as spindle torque as discussed above, and fully controllable means of adjusting the die lip profile shape on-line during the extrusion or coating process itself.
- a 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 of the flexible die lip or choker bar when not being flexed open or closed by a force application mechanism.
- “blocked zones” refer to those areas along the width of the slot die that are aligned with the deckle, where extrudate cannot pass through the applicator slot. “Unblocked zones” refer to those areas along the width of the slot die that are not aligned with the deckle, where extrudate can pass through the applicator slot. Deckles preferably have a thickness similar to that of the applicator slot in its neutral position to avoid creating a discontinuity in slot height between the blocked and unblocked zones.
- the control scheme preferably constrains the assigned actuator settings such that the die lip or choker bar slot height profile over a blocked zone and that over a neighboring unblocked zone converge to the same value where the blocked and unblocked zones come together.
- the convergence of cross-web slot height profile where the blocked and unblocked zones come together is a monotonic convergence.
- the convergence is not a monotonic convergence, but a sinusoidal convergence.
- the actuator settings in the vicinity of at the transition point between the blocked and unblocked zones are automatically or semi-automatically constrained by the controller to reduce the amplitude of oscillation relative to the cross-web profile that would be obtained in absence of such constraints.
- Deckles can be used even if the actuators are not engaged to a die lip. For example, one could use a plurality of actuators that engage a choker bar across the full width of the die slot, even when a portion of the applicator slot is blocked with one or more deckles at the die exit. With the deckles present, the precise configuration of the choker bar would not control the flow in the blocked slot areas, but would nonetheless exert some influence as a result of bending interactions (i.e., convolutions) with unblocked areas along the die slot.
- the actuator settings are predictively programmed to arrive at a fixed target slot position over the blocked zones of the slot (“freeze slot mode”).
- actuators are not frozen but rather manipulated by the controller, based for example on fluid physics calculations, to arrive at a fixed slot profile. In some embodiments, this is an iterative process, where actuator settings can be adjusted more than once to converge on the desired fixed slot profile.
- the choker bar along the blocked zones ride along with the adjacent outer portion of the open die slot (“slave mode”).
- slave mode the actuators over the blocked zone become the “slave” of the last actuator in the unblocked zone.
- this freeze slot mode can be accomplished by manipulating the fluid physics in the freeze slot actuator zones.
- Actuator #1 and #2 are frozen, while the segment of applicator slot corresponding to Actuator #3 is not blocked and yields good caliper data.
- the average caliper measurement over the unblocked actuator zone can be substituted for the non-existent caliper data in the blocked Actuator zones (i.e., Actuator #1 and #2).
- the matrix methods will hold the slot constant by manipulating the actuator positions to account for their convolution interaction.
- Adjusting the relative position of Freeze Slot 1 or Freeze Slot 2 compared to Actuator 3 can be achieved by: (1) suspending the automated fluid physics control; (2) adjusting the positions of Actuators #1 and/or #2 as desired; and then (3) resuming the automated fluid physics control.
- the result is that Actuator #1 and #2 remain as Slaves, but their positions are defined relative to new starting points accounted for in the adjusted slot height Bi
- the location at which actuators with fixed settings transition to actuators with dynamic settings can be advantageously adjusted by an operator based on the application at hand.
- This transition location can be made relative to the position of one or more deckles within the applicator slot.
- the aggressiveness of the freeze can be tailored according to the following three options (in these descriptions, “z” represents actuator number):
- Freeze Option A Freeze to (i+1) when the deckle is past z (most aggressive)
- the predicted actuator settings near to where this transition occurs may be further adjusted to provide for a monotonic convergence between the cross-web slot height profile along the unblocked zone and the cross-web slot height profile average over the blocked zone.
- this adjustment can be made manually, automatically, or semi-automatically.
- the idealized result of this adjustment is represented by the solid lines in FIGS. 21 and 22, with actual slot profile values represented by the bar chart.
- a monotonic convergence was achieved for the deckle boundary on the left side of the chart but not on the right side, where an undesirable kink remained in the slot height profile.
- the controller can send instructions to the actuators to automatically or semi-automatically enlarge the cross-web slot height profile along an unblocked zone of the applicator slot, while tapering down the degree of enlargement along a transition zone between the unblocked zone and the blocked zone.
- the transition zone can extend over three, four, or even more than four consecutive actuators.
- controller 300 may be implemented, at least in part, in hardware, software, firmware or any combination thereof.
- various examples of the techniques may be implemented within one or more microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), or any other equivalent integrated or discrete logic circuitry, as well as any combinations of such components, embodied in controllers, user interfaces or other devices.
- DSPs digital signal processors
- ASICs application specific integrated circuits
- FPGAs field programmable gate arrays
- controller may generally refer to any of the foregoing logic circuitry, alone or in combination with other logic circuitry, or any other equivalent circuitry.
- the functionality ascribed to the systems and controllers described in this disclosure may be embodied as instructions on a computer- readable storage medium such as random access memory (RAM), read-only memory (ROM), non-volatile random access memory (NVRAM), electrically erasable programmable read-only memory (EEPROM), FLASH memory, magnetic media, optical media, or the like.
- RAM random access memory
- ROM read-only memory
- NVRAM non-volatile random access memory
- EEPROM electrically erasable programmable read-only memory
- FLASH memory magnetic media, optical media, or the like.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Extrusion Moulding Of Plastics Or The Like (AREA)
Abstract
La présente invention concerne des procédés de fonctionnement d'une filière en forme de fente comprenant une fente d'applicateur s'étendant dans le sens d'une largeur de la filière en forme de fente, la fente d'applicateur étant en communication fluidique avec un trajet d'écoulement de fluide à travers la filière en forme de fente, et au moins un élément d'un groupe constitué de : une barre de contrôle et une lèvre de filière flexible. La forme de la barre de contrôle ou de la lèvre de filière flexible peut être manipulée en appliquant, avec un mécanisme d'application de force, des forces qui sont généralement parallèles à la largeur de la filière en forme de fente. L'invention concerne en outre des procédés de fonctionnement et de purge d'une filière en forme de fente, au moins une partie de la fente d'applicateur étant bloquée avec une ou plusieurs réglettes pour réduire une largeur efficace de la fente d'applicateur.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/IB2020/061687 WO2022123295A1 (fr) | 2020-12-09 | 2020-12-09 | Procédé et système de réglage de filière en forme de fente utilisée pour la fabrication d'un article extrudé |
Publications (1)
Publication Number | Publication Date |
---|---|
EP4259414A1 true EP4259414A1 (fr) | 2023-10-18 |
Family
ID=73855520
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP20828126.1A Pending EP4259414A1 (fr) | 2020-12-09 | 2020-12-09 | Procédé et système de réglage de filière en forme de fente utilisée pour la fabrication d'un article extrudé |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP4259414A1 (fr) |
JP (1) | JP2023553100A (fr) |
MX (1) | MX2023006851A (fr) |
WO (1) | WO2022123295A1 (fr) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2024016023A1 (fr) * | 2022-07-12 | 2024-01-18 | Brownlow George | Procédé de revêtement d'un tuyau |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE9422051U1 (de) * | 1994-02-04 | 1997-09-25 | Extrusion Dies, Inc., Chippewa Falls, Wis. | Flexible Doppellippen-Extrusionsvorrichtung |
US5679383B1 (en) * | 1994-02-04 | 1999-01-05 | Extrusion Dies Inc | Dual flexible lip extrusion apparatus |
BR112013031333B1 (pt) * | 2011-06-07 | 2020-12-01 | 3M Innovative Properties Company | sistema para ajuste de posição de matriz em fenda |
JP6399850B2 (ja) | 2014-08-05 | 2018-10-03 | 住友重機械モダン株式会社 | ダイリップ駆動構造 |
US9815237B2 (en) * | 2015-02-20 | 2017-11-14 | Nordson Corporation | System for adjusting the land channel length on an extrusion die |
DE102018111763A1 (de) | 2018-05-16 | 2019-11-21 | Windmöller & Hölscher Kg | Verfahren zur automatisierten Regelung der Größe eines Spaltes einer Düsenanordnung und Steuer- und/oder Regelsystem |
-
2020
- 2020-12-09 EP EP20828126.1A patent/EP4259414A1/fr active Pending
- 2020-12-09 JP JP2023534894A patent/JP2023553100A/ja active Pending
- 2020-12-09 WO PCT/IB2020/061687 patent/WO2022123295A1/fr active Application Filing
- 2020-12-09 MX MX2023006851A patent/MX2023006851A/es unknown
Also Published As
Publication number | Publication date |
---|---|
JP2023553100A (ja) | 2023-12-20 |
WO2022123295A1 (fr) | 2022-06-16 |
MX2023006851A (es) | 2023-08-14 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US9744708B2 (en) | Slot die position adjustment and return to baseline | |
US9579684B2 (en) | Slot die position adjustment control | |
KR102118074B1 (ko) | 슬롯 다이의 위치를 조정하기 위한 시스템 | |
US9216535B2 (en) | Slot die position adjustments to facilitate patterned products | |
CN107848001B (zh) | 用于改变金属带材温度以调整平整度的方法和装置 | |
US6314776B1 (en) | Sixth order actuator and mill set-up system for rolling mill profile and flatness control | |
JP6475229B2 (ja) | 焼鈍炉のための炉マッフル | |
EP4259414A1 (fr) | Procédé et système de réglage de filière en forme de fente utilisée pour la fabrication d'un article extrudé | |
EP4259413A1 (fr) | Procédé et système de réglage de filière en forme de fente utilisée pour la fabrication d'un article extrudé | |
CN111168868B (zh) | 线切割装置及工件切割方法 | |
US20220259721A1 (en) | Deposition Processing Systems Having Active Temperature Control and Associated Methods | |
KR20070050073A (ko) | 쉬터 간격 조정 및 수압식 작동 | |
JP2024069307A (ja) | リンギング制約を伴うスロットダイ位置調整 | |
KR20160067826A (ko) | 스퍼터 장치 | |
JP6932527B2 (ja) | ロール温調による塗工隙間制御を用いた塗工装置および塗工方法 | |
JP2024537095A (ja) | 調整された剛性、低減された延伸ゾーン、及び力バジェットを有するスロットダイアセンブリ | |
JP2023553102A (ja) | スロットダイ位置調整 | |
JP6597114B2 (ja) | 塗布装置及び塗布方法 | |
CN117083161A (zh) | 唇间隙调整装置、挤出成型模具、挤出成型装置、调整唇间隙的方法和制造薄膜的方法 | |
WO2022219379A1 (fr) | Réglage de filière plate avec commandes hybrides | |
JP6186976B2 (ja) | シート状材料の冷却制御方法及び装置 | |
WO2024136855A1 (fr) | Filière à fente et ses méthodes de fonctionnement |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: UNKNOWN |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE |
|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE |
|
17P | Request for examination filed |
Effective date: 20230607 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
DAV | Request for validation of the european patent (deleted) | ||
DAX | Request for extension of the european patent (deleted) |