KR20070083825A - Coating die with quick assembly shape - Google Patents

Abstract

The slot coating die 10 is arranged to clamp at least the first portion 12 and the second portion 14 and the first portion against the second portion, which together form a cavity in fluid communication with the first applicator slot. At least one quick release fastener. The invention is particularly suitable for installation of a multilayer coating die, including a third portion, wherein the second portion and the third portion together form a second cavity in fluid communication with the second applicator slot. A good back acting quick release fastener eliminates the need to disassemble the entire die to access one of the interior parts to replace the shim or to clean the slot.

Applicator slot, cavity, quick release fastener, multilayer coating die

Description

COATING DIE HAVING QUICK ASSEMBLY FEATURES}

FIELD OF THE INVENTION The present invention generally relates to the construction of a die for applying a coating material, for example to a web of non-limiting length material, and more particularly to a coater having a shape that promotes rapid assembly and disassembly.

It is well known to coat a fluid onto a web material. Such coatings are often conveniently performed using a coating die having a cavity in communication with an applicator slot. The liquid under pressure is introduced into the cavity and then extruded from the applicator slot onto a desired substrate, such as, for example, a web of discrete length material or an individual article.

In die coating, it is highly desirable to implement precise control of die geometry to achieve a die assembly having a uniform slot height. The uniformity of the slot height is a function of the joining method, stiffness and flatness for the two parts containing the die. Shims may be employed (often employed) between die portions, and the uniformity of their dimensions is also a factor. Preferably, this uniform slot is in fluid communication with the cavity in the die in such a way that a uniform flow is maintained across the width of the die when the fluid to be coated is pumped under pressure into the cavity.

More complex multilayer dies with one or more applicator slots are known and used to uniformly spread two or more liquid layers simultaneously to coat webs or individual articles of non-limiting length material. Precise control of the die becomes more difficult when the number of layers increases, and cascading errors occur during assembly. Typically, the manifold and metrology slots for the layers in a multilayer die are precisely machined using standard fasteners, such as bolts, which screw two parts down through the top of one part to the next. It is formed by joining two metal parts. This causes several problems with multi-layer dies, such as having to disassemble the entire die to access one of the inner layers to replace the seams or clean the slots. Often this is because the upper part for the next layer is covered over the fasteners that join the underlying section to the next section below.

The use of bolts to assemble a coating die introduces a second problem between layers, for example a die without fastening pins, to ensure specific alignment. This alignment is desirable when it is desirable to allow the two layers that together form the manifold cavity and its associated applicator slot to be repositioned during assembly, in order to vary the overbite between the edges at the exit end of the slot. Pins are often removed. The reaction torque from the first bolt being clamped is likely to distort the upper part relative to the lower part, and the setting is often compromised unless the part is strictly inhibited from rotating before the bolt is snugging down.

The present invention provides a multilayer slot coated die configured to precisely join the main die portions together in a manner that allows the user to independently assemble, reposition or disassemble the individual layers without disturbing other already assembled layers. This is conveniently accomplished by a series of quick release fasteners that are preferably installed in recesses specially designed in the die body. Cams that rotate along an axis parallel to the plane of separation of the die are particularly convenient as these quick release fasteners. Such fasteners allow unrestricted access to the fasteners through the exposed back of the die at any point during the assembly process, even after multiple layers have been assembled up and down.

More specifically, the present invention provides at least a first and a second portion that together form a die cavity in fluid communication with the first applicator slot, and at least one quick release fastener disposed to clamp the first portion to the second portion. It can be considered an apparatus comprising a die having a. More generally, there is at least a second quick release fastener arranged to clamp the first portion against the second portion, which is better at resisting any forces that cause the die position to twist against each other. In fact, a large number of quick release fasteners may be required for a very wide die to provide sufficient stability and clamping force.

In a preferred embodiment, the quick release fastener is in a form such that the first portion of the die can be clamped by the quick release fastener over a range of positions relative to each other with respect to the second portion, the range of which is the first applicator slot. Is oriented in a direction perpendicular to. This allows the operator to assemble the die so that one edge of the applicator slot provides the exact amount of offset that will be advanced relative to the other edge for the substrate being coated. The offset is sometimes referred to in the art as "overvite" when the lower web edge of the slot is advanced towards the roll as compared to the upper web edge, and "underbite" when reversed. More information on the use of offset die edges in die coating is disclosed in US Pat. No. 5,759,274, issued by Maier et al., Which is incorporated herein by reference. It is particularly convenient if the quick release fastener is operable from the rear of the die compared to the applicator slot.

The invention is particularly suitable for installation of a multilayer coating die, including a third portion, wherein the second portion and the third portion together form a second cavity in fluid communication with the second applicator slot. A good back actuated quick release fastener eliminates the need to disassemble the entire die to access one of the interior parts to replace the shim or to clean the slot.

One particularly convenient quick release fastener that can be used in connection with the present invention includes a stud attached to one of the first or second portions and configured to extend into a recess in the other portion. The other part has a rotatable cam arranged to exert a variable force on the stud as it rotates.

Although it is desirable to provide a fast release fastener such as a bolt to adjust the expected force to separate the die portion, the quick release fastener of the type just described may facilitate assembly of the die. More specifically, such cam braking fasteners maintain a torsional force around an axis perpendicular to the plane of separation of the die portion, such as how the bolt acts when torque is applied. As such, if such a cam braking fastener is provided and used to brake the die portion together before the bolt is adopted, the clamping force may be used to resist any tendency for the bolt to go out of alignment and twist the die portion. will be.

With this in mind, the present invention also assembles a coating die comprising at least a first and a second die portion together to form a cavity in fluid communication with the first applicator slot, and the first portion with respect to the second portion. It may also be considered as a method of forming one or more quick release fasteners disposed to clamp and actuating the quick release fastener. In many preferred embodiments, the quick release fastener is of a type such that the first portion can be clamped by the quick release fastener over a range of positions relative to each other with respect to the second portion, the range being the first applicator slot. Is oriented in a direction perpendicular to. In these embodiments, the method may further include placing the first portion within a range of positions relative to the second portion to achieve a predetermined offset between the first portion and the second portion in the applicator slot.

In any preferred variant of this method, the quick release fastener is formed to maintain a torsional force around an axis perpendicular to the plane of separation of the die portion. In these variants, the method very easily accommodates the additional step of clamping the first part to the second part with one or more quick release fasteners.

In the several figures of the accompanying drawings, like parts have like reference numerals.

1 is a perspective view of an exemplary coating die in accordance with the present invention.

2 is a detailed exploded perspective view highlighting the preferred form of the quick release fastener.

It will be appreciated that the above description is for illustrative purposes only and is not intended to be limiting. It will be apparent to those skilled in the art that various modifications and variations of the present invention may be made from the foregoing techniques without departing from the scope of the present invention, and that the invention is not limited to the exemplary embodiments disclosed herein.

[Justice]

The distribution chamber of most coating dies typically has a general shape. They comprise a cavity (also sometimes referred to in the art as a distribution chamber or channel) that is oriented substantially in the cross-web direction and connected to an applicator slot (sometimes referred to in the art as a slit or land). As used herein, the term “manifold” refers to the cavity and any other passage between the cavity and the applicator slot, as defined above, and includes an applicator slot.

As used herein, the term "clamp" means using a mechanism to apply a force intended to secure two objects in a positional relationship to each other. This does not imply that the two objects are actually in contact. (In the context of the present invention, the die portions are often separated slightly by inflexible shims. However, they are clamped when the instruments are used to fix their relative positions.)

Referring to FIG. 1, a front perspective view of an exemplary coating die 10 is shown. Coating die 10 includes a first die portion 12, a second die portion 14, and a third die portion 16. In many convenient embodiments, these portions are separated by shims, as illustrated herein with shims 18, 20. This makes it possible to conveniently adjust the height of the applicator slot. First applicator slot 22 and second applicator slot 24 are conveniently formed by shim 18 and shim 20, respectively. The applicator slots 22, 24 are in fluid communication with the fluid distribution cavity formed by the first die portion 12 and the second die portion 14 and the second die portion 14 and the third die portion, respectively. Is masked in the example of the assembled coating die 10.

In the present invention, there is one or more quick release fasteners adapted to clamp the first portion 12 against the second portion. The quick release fasteners can be operated without repeated operation, and various mechanical measures will be apparent to those skilled in the art. Rotatable and linear cam placement, taper connection and overcenter toggle are non-limiting examples of quick release fasteners. In the context of the present invention, the quick release fastener can be clamped by a quick release fastener over a range of positions relative to each other with the first portion, the range being perpendicular to the first applicator slot. Most preferred is a piece that is shaped to be oriented in a direction. In addition, a mechanized device may be used to engage or disengage the quick release fastener.

A quick release fastener that can provide this advantage is shown in FIG. 2, which is a detailed exploded perspective view focusing on the quick release fastener. An isolated portion of the first die portion 12 is shown separated from the second die portion 14 at its original dividing line. The first die portion 12 is provided with a recess 40 extending in a direction perpendicular to the dividing line. The recess 40 is crossed by a transverse bore 42 extending into the opening 44 in the rear face 46 of the first die portion 12. The recess 40 is sized to receive a stud 48 mounted within the die portion 14. The stud 48 has a support surface 50 which is conveniently shaped to interact with the rotatable cam 52. The stud 48 is mounted such that the support surface 50 can be clamped in any one of the plurality of positions in a direction perpendicular to the separation plane of the die portions 12, 14. The rotatable cam 52 is shaped to exert a varying force to attract the first die portion 12 towards the second die portion 14 according to its rotational position relative to the support surface 50. The rotatable cam 52 is conveniently provided with a tool feature 54 so that it can be adjusted within the cross bore 42 with a tool such as a screwdriver, square drive wrench or Allen wrench, depending on the details of the feature. . The braking setting screw 56 is provided to hold the rotatable cam 52 which is spring loaded against it in the cross bore 42 after assembly. The rotatable cam 52 preferably has a notch 58 on the exposed surface to provide tactile feedback to the user, and is released each time the notch 58 rotates into the proximity of the tip of the set screw 56. And click into the correct rotational position for die disassembly. In addition, the rotatable cam 52 is marked on the exposed surface to indicate the correct rotational position for release. The set screw 56 also provides a means for adjusting the axial position of the rotatable cam 52 by an inclined tip on which the cam 52 under spring load slides. Turning the set screw 56 further into the die causes the rotatable cam to further retract into the recess that houses the rotatable cam 52.

Example 1

The coating die, each 25 cm wide and having two applicator slots shown in FIG. 1, was prepared from stainless steel and six quick release fasteners were provided as shown in FIG. More specifically, these quick release fasteners include studs suitable for the D1-2 "camlock spindle nose. The studs are 11 mm (7/16") in diameter and the support surface is 40 ° vertically. Incline The studs are formed with 3 / 8-24 UNF threaded threads so that the height of the studs can be adjusted in 1 mm (41 mil) increments during initial assembly. The linear cam has a 210 ° shape that is 1.6 to 0.1 mm (0.063 "to 0.004") less than the outer periphery, nominally 15.8 mm (5/8 ") in diameter, and has a rise of about 1.5 mm (60 mil). The eccentricity of the stud follower to is 9.1mm (0.358 ").

The coating dies described were pressure tested to compare the performance of the camlock fasteners to the performance of conventional cap screws typically used to join the die portions together. A 0.09 mm (3.7 mil) layer of 3M 5490 extruded PTEE (3M Company, St. Paul, Minn.) Tape was applied to the separating surface of the upper block, which was then laminated to the top of the lower block. The fitting is connected to a Rosemount 3051C pressure transmitter (Emerson Process Management, Rosemount Division, Chanhassen, Minnesota, Chanhasen, Minn.) And an air pressure regulator to connect it to the bottom block to connect it. Screwed into supply port.

Mitutoyo Digimatic digital indicator {Mitutoyo / MTI Corporation, Aurora, Illinois, Aurora, Illinois} has the axis of the indicator perpendicular to the separation plane and the exit end of the slot. It is mounted to a bottom block using a magnetic stand such that it is directly above the top block located on a line of symmetry with respect to the nearby assembly. The indicator is then zeroed to the top surface of the upper block parallel to the separation plane.

The blocks are then joined together by hand tightening the cam clockwise with a 6.35 mm (1/4 ") square end driver. When the block is pressurized to 4.2186 kg / cm 2 (60 psig), the indicator is 0.076 mm (3 mil) The air is blown out of the die along the edge of the separation plane opposite the supply port side, then the air pressure is vented and the cam has a torque of about 69.128 kgcm (60 in-lbs). At this time the indicator reading is unchanged and there is no leakage of any audible noise When the air supply is cut off, the pressure in the block drops slowly to zero over a period of three minutes.

Comparative example

For comparison, the coating die was prepared approximately similarly to the coating die of Example 1, except that the quick release fasteners were replaced with conventional 3 / 8-24 socket head cap screws that completely penetrated the upper block. This fastener has a torque of 60 inches-lbs (69.128 kgcm) and receives a maximum torque of 1/6. The results were similar to the test where the quick release fasteners were also torqueed to 60 in-lbs (69.128 kgcm). Increasing the torque on the cap screw to 480 in-lbs (553.027 kgcm) produces the same result. The reduction in torque on the cap screw down to 30 in-lbs (34.564 kgcm) results in a lip strain of 0.0076 mm (0.3 mil). This shows that the convenience of quick release fasteners can be achieved without loss of sealing force.

Claims (19)

A die having together at least first and second portions forming a manifold in fluid communication with the first applicator slot; And at least one quick release fastener disposed to clamp the first portion relative to the second portion. The apparatus of claim 1, further comprising at least a second quick release fastener disposed to clamp the first portion to the second portion. The method of claim 1, wherein the first portion is shaped such that it can be clamped by a quick release fastener over a range of positions relative to each other with respect to the second portion, wherein the range is perpendicular to the first applicator slot. Oriented device. The apparatus of claim 1, wherein the quick release fastener is operable from the rear of the die compared to the applicator slot. The apparatus of claim 1, wherein the coating die further comprises at least a third portion to form a second manifold in which the second portion and the third portion are in fluid communication with the second applicator slot. 6. The apparatus of claim 5, wherein one or more quick release fasteners are disposed to clamp the second portion to the third portion. The method of claim 1, wherein the quick release fastener comprises a stud attached to one of the first portion or the second portion and adapted to extend into a recess in the other portion; And a rotatable cam positioned to exert a force on the stud as it rotates. 8. The device of claim 7, wherein the force on the stud is variable depending on the degree of rotation of the rotatable cam relative to the stud. 8. The apparatus of claim 7, wherein the rotatable cam is accessible from the rear of the die compared to the applicator slot. The apparatus of claim 9, wherein the first portion can be clamped by a quick release fastener over a range of positions relative to each other with respect to the second portion, the range being oriented in a direction perpendicular to the axis of the applicator slot. . Forming together at least first and second portions that form a manifold in fluid communication with the first applicator slot; Forming one or more quick release fasteners disposed to clamp the first portion against the second portion; Operating the quick release fastener. 12. The method of claim 11, further comprising: forming a second quick release fastener disposed to clamp the first portion relative to the second portion; Operating the second quick release fastener. 12. The quick release fastener of claim 11 wherein the quick release fastener is of a type such that the first portion can be clamped by the quick release fastener over a range of positions relative to each other with respect to the second portion, wherein the range is in the first applicator. Oriented perpendicular to the slot, And placing the first portion within a range of positions relative to the second portion to achieve a predetermined offset between the first portion and the second portion in the applicator slot. The method of claim 11, wherein the quick release fastener is operable from the rear of the die compared to the applicator slot. The coating of claim 11, wherein the coating die is a multilayer die, further comprising providing at least a third portion to form a second manifold in which the second portion and the third portion are in fluid communication with the second applicator slot. Die assembly method. 12. The device of claim 11, wherein the quick release fastener comprises: a stud attached to one of the first or second portions and configured to extend into a recess in the other portion; And a rotatable cam positioned to exert a force against the stud as it rotates. 17. The method of claim 16, wherein the force on the stud is variable depending on the degree of rotation of the rotatable cam relative to the stud. 18. The method of claim 17, further comprising disposing a shim having a thickness selected from a range of thicknesses between the first portion and the second portion, The rotation of the rotatable cam can exert a variable force on the stud when any of the possible shims are so disposed. 13. The method of claim 12, wherein the quick release fastener is configured to maintain without applying a torsional force about an axis perpendicular to the plane of separation of the die portion.

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