DE102016205168A1 - Device and method for adjusting the outflow opening of an extruder head - Google Patents

Abstract

The invention relates to a device for adjusting the outflow opening of an extruder head (1), wherein the extruder head (1) has an upper part (2) and a lower part (3), wherein on the upper part (2) and on the lower part (3) in each case a strip ( 20, 30) is formed, which form a nozzle gap (4) for the passage of extrudable mass (5), wherein at least one strip (20, 30) in the exit direction of the material flow of the extrudable mass (5) at least one flexible lip (21, 31) is designed for contouring the extrudable mass (5) and that the at least one flexible lip (21, 31) is in operative connection with at least one actuating element (7) and a method for operating a device for adjusting the outflow opening of an extruder head (1) ,

Description

The invention relates to a device for adjusting the outflow opening of an extruder head and to a method for its operation.

The DE 1 704 481 A relates to a slot die with adjustable lip gap for the production of foil strips or plates of thermoplastic compositions with a arranged in a two-part nozzle housing, intended for receiving the die lips hollow cylindrical recess, wherein the recess extends to both parts of the nozzle housing and in the recess to form the gap , Two nozzle lips forming, is arranged in its longitudinal axis or parallel to it in two parts intersected solid cylinder. The in the DE 1 704 481 A disclosed device allows only to change the gap size of the outlet opening, however, the contour of the exiting from the extruder mass can not be affected.

The US 2,720,679 as well as the US 3,195,183 each reveal a variety of blades (blades) which act on the mass to be extruded. Each blade has a separate actuator. This construction is complex and involves the risk that the abutting edges between the blades are apparent in the extruded mass. Furthermore, mass to be extruded can penetrate into the areas between the blades and impair their function or even lead to the failure of the blades and thus lead to failure of the extruder.

The DE 2305 877 A discloses a device for continuously changing the outflow opening of an extruder head, wherein at least one of the outflow opening and the upper part and lower part of the chamber located in front of the opening is formed by the force of the pressure formed on the extruder head deformed steel sheets, with supports whose position continuously by pressure arms of Piston hydraulic units of controlled organs is changeable, are limited. This construction is very complicated and therefore prone to failure.

The invention is therefore based on the object to propose a device for adjusting the outflow opening of an extruder head, which is simple in construction and thus offers a low risk of failure at low investment costs, as well as a time and cost saving method for operating a device for adjusting the outflow opening of an extruder head propose.

This object is achieved according to the invention by a device for adjusting the outflow opening of an extruder head, wherein the extruder head has a top and a lower part, wherein in each case a bar is formed on the upper part and the lower part, which form a nozzle gap for the passage of extrudable mass, wherein at least a strip is formed in the exit direction of the material flow of the extrudable mass at least one flexible lip for contouring the extrudable mass and that the at least one flexible lip is in operative connection with at least one actuating element.

By positioning the at least one flexible lip on the side of the extruder head facing away from the extruder, this at least one flexible lip is not exposed to the full material flow of the extrudable mass. The force on the at least one flexible lip is thus lower. The at least one flexible lip only comes into contact with a preformed material strand at the outflow opening of the extruder head or nozzle. Flexible means that the at least one lip is movable, bendable, flexible, elastic, resilient, changeable, with regard to its position with respect to the flow of material and the at least one actuating element.

The position of the at least one flexible lip in relation to the preformed material strand can thus be selectively changed. As a result, the material strand receives its predetermined shape or contour when leaving the outflow opening of the extruder head. The material strand generates a force in the direction of the at least one actuating element, so that the at least one flexible lip comes to rest on the side remote from the material strand on the at least one actuating element. The effect of the at least one actuating element is that the at least one flexible lip can avoid the material strand only the path predetermined by the position of the at least one actuating element in the direction of the at least one actuating element. If a plurality of actuation elements are arranged on the side of the at least one flexible lip remote from the material strand, the contour of the material strand when leaving the outflow opening of the extruder head can thereby be predefined.

Furthermore, the invention provides that the at least one flexible lip is at least in the end region of its longitudinal extent force, form and / or cohesively fixed to at least one bar. This makes it possible that the at least one flexible lip is defined only at its end points in its longitudinal extent. In the area between the at least one flexible lip is perpendicular, or almost vertically adjustable with respect to the flow of material.

Furthermore, the invention provides that the at least one actuating element is mounted positively movable on the at least one bar. By the storage of the at least one actuating element in the at least one flexible lip associated strip, a defined adjustment of the position of the at least one flexible lip with respect to the material strand is possible. The actuator can be supported in the bearing and thus build up a force for supporting the at least one flexible lip. The counterpressure forms the extrudable mass flowing through the die gap. Due to the material flow of the extrudable mass and the adjustment of the at least one actuating element, the at least one flexible lip assumes a defined position during the operation of the extruder. This defined position determines the contour of the flowing extrudable mass. As soon as no extrudable mass is applied to the at least one flexible lip, it assumes an undefined position. Only through the interaction of extrudable mass and at least one actuating element takes the at least one flexible lip a defined position. The at least one flexible lip can only escape the pressure of the extrudable mass until it comes to rest on at least one actuating element. The at least one actuating element serves as travel limit for the deflection of the at least one flexible lip. The more the at least one actuating element is adjusted in the direction of the flow of material, the smaller becomes the outlet opening of the extruder head. If the at least one actuating element is moved away from the material stream of the extrudable mass, the outlet opening of the extruder head increases. Regardless of the selected setting of the at least one actuating element, the material flow of the extrudable mass is given a defined contour only when the at least one flexible lip comes into contact with the at least one actuating element.

Furthermore, the invention provides that the at least one flexible lip is made of metal or a metal alloy. Metals and metal alloys are heat resistant and durable, and are advantageously used to make the at least one flexible lip. The at least one flexible lip is regularly exposed to high processing temperatures of the extrudable mass.

Furthermore, the invention provides that the at least one flexible lip is formed as a metal strip. A sheet metal strip is deformable so that almost any desired contour for the extrudable mass can be adjusted.

Furthermore, the invention provides that at least one flexible lip on its side facing the extrudable mass has a lubricious coating. By a sliding coating, the friction between the at least one flexible lip and the extrudable mass is reduced.

Furthermore, the invention provides that the at least one actuating element is designed as an adjusting screw, which is mounted in at least one threaded hole. An adjusting screw offers a precise adjustment possibility for the at least one flexible lip depending on the selected thread. In its longitudinal extent or along its flight, the adjusting screw can pass more than one threaded hole. This may be necessary, for example, due to material savings in the area of the at least one bar.

Furthermore, the invention provides that on the Oberteilendleiste a flexible upper lip and the dividing end strip is arranged a flexible lower lip. This can be influenced from two sides to the contour of the material strand.

The object stated at the outset is furthermore achieved by a method according to the invention for operating a device for adjusting the outflow opening of an extruder head, wherein the contour of the extrudable material strand emerging from the outflow opening of the extruder head is aligned with the target contour, whereupon the at least one flexible lip interacts with at least one actuating element for adjustment, preferably fine adjustment of the contour of the material flow of the extrudable mass is adjusted depending on the deviation from the target contour of the material strand. Due to the fact that only a fine adjustment takes place by this method, the device can be constructed significantly simpler and more cost-effectively.

Furthermore, the invention provides that the adjustment of the at least one flexible lip by adjusting the at least one actuating element takes place during the extruder process. The running-in process no longer needs to be interrupted by the device according to the invention and the method according to the invention made possible in order to set the desired contour for the material strand.

Furthermore, an adjustment of the at least one flexible lip can also take place during the production process.

In other words, the end bar of the extruder head consists of a top end bar and a bottom end bar. The opening of the profile, the die gap is made by machining with geometric undefined cutting such as milling or filing generated. Alternatively, the opening of the profile can be produced by electroerosion.

Electro-erosion is the generic term for all machining operations caused by electrical discharge processes between two electrodes (workpiece, tool) in a working medium. Electro-erosion includes spark erosion and arc erosion.

By this manufacturing method, an opening is created, which corresponds approximately to the desired profile geometry. So far, the procedure is identical to the production of known from the prior art end strips. These had to be removed again and again in the run-in process and reworked until the strand consisting of extrudable mass had the desired outer contour. The removal and installation of these end strips in the extruder head is expensive, time-consuming and therefore costly. Furthermore, a large amount of extrudable mass is generated during the run-in process.

In order to shorten the Einfahrprozess and reduce the effort, at least one flexible lip is proposed according to the invention, which comes into contact with the extrudable mass. This flexible lip is in contact with at least one actuating element which allows an adjustment of the position of the flexible lips.

The resulting between the end strips nozzle gap must be worked out during the production of the end strips only roughly from the material. The desired contour of the extrudable mass can be influenced and established by the at least one flexible lip.

The start profile opening must therefore correspond only approximately to the final (initially unknown) profile opening. The fine adjustment takes place in the installed state. The possible reachable adjustment ranges are determined by the choice of steel for the lips, the uniformity of the nozzle contour, the length and the thickness of the at least one lip.

Due to the arrangement of the at least one lip on the side of the extruder head facing away from the extruder, the entire material flow of the extrudable mass does not act on the at least one lip. This entire material flow acts only on the mold gap forming strips or on the upper and lower part of the extruder head. The strips cause a profiled strand to form from the extrudable mass before it contacts the at least one lip. The at least one lip thus serves only to form the final contour of the strand or of the profile. With this contour, effects such as shrinkage or increase in volume must be taken into account in the formation of the finished product or semifinished product.

Compared to the devices known from the prior art for adjusting the outflow opening of an extruder head, the adjusting device in the form of at least one flexible lip is not exposed to the full flow of material, but rather to a flow of material already regulated by entry into the die gap. As a result, lower forces act on the at least one flexible lip, the adjusting device can thus be constructed simpler. The operational reliability for the adjusting device and thus for the entire extruder process increases. The probability of failure for the extruder process due to faults at the extruder head drops.

In order to maintain the temperature of the extrudable mass at the desired level during passage through the nozzle, the nozzle housing is bypassing electrical heating elements such as heating plates. The temperature of the extrudable mass or the housing is monitored by thermocouples.

In a further embodiment of the invention, in each case flexible lips are arranged on a top end strip and on the dividing strip arranged opposite to it. At least one actuating element acts on each of these flexible lips.

The more actuators per unit length of the flexible lips are arranged, the more precisely the contour of the extrudable mass can be influenced.

Each lip to be adjusted is adjusted by a series of actuators, such as adjusting screws, which are located above or below the lip in a guide device. The guide device may for example be designed as a threaded bar.

By turning an adjusting screw of the nozzle gap can be reduced in the range of the pressure point of the adjusting screw, resulting in a thinner profile. By turning the adjusting screw in conjunction with the material pressure of the exiting extrudable mass, the lip is moved upwards, in the upper part or down, in the lower part, the extruded profile is thus thicker. By opening or loosening the individual adjustment screws, the nozzle opening can be adjusted segment by segment.

An extrudable mass may for example be formed from a rubber mixture or rubber compound. These extrudable materials can be used to make semi-finished products for the production of elastomeric products.

Furthermore, for example, elastomeric products can be produced from extrudable materials. Elastomeric products serve, for example, for the production of tires or for the production of tire components and for the production of conveyor belts, hoses, air spring bellows, drive belts, diaphragms, vibration dampers and other rubber products.

The term tires includes vehicle tires and pneumatic vehicle tires.

Hereinafter, an embodiment will be explained in more detail with reference to the attached figures.

Show it:

1 shows a schematic spatial representation of an extruder head and

2 a section of a schematic representation of a front view of the extruder head.

In the following description of the figures, terms such as top, bottom, front, back, left, right and the like refer exclusively to the exemplary representation and position of the device and other elements selected in the respective figures. These terms are not intended to be limiting, that is to say that different positions and / or mirror-symmetrical design or the like may change these references.

Identical elements are given the same reference numbers in both figures and in the following description.

The 1 shows an extruder head 1 with a device for adjusting the outflow opening of the extruder head 1 , The extruder head 1 has a top 2 and a lower part 3 , Between shell 2 and lower part 3 is a nozzle gap 4 arranged, which has an outflow opening at the extruder head 1 formed. This nozzle gap 4 is made of extrudable mass 5 (please refer 2 ) flows through. Due to the selected representation and for clarity was on the representation of the extrudable mass 5 in the 1 waived. With an arrow and the reference numeral X is the material flow direction of the extrudable mass 5 shown.

The top 2 has a top end bar 20 on. At this top end bar 20 is an upper lip 21 formed, which in operation in contact with the extrudable mass 5 stands. To influence the contour of the mass to be extruded 5 to take is the upper lip 21 flexible execution. Above the upper lip 21 are upper threaded holes 22 arranged, which actuators 7 , for example, executed as adjusting screws record.

The lower part 3 has a subdivision end bar 30 on. At this Teilerteilendleiste 30 is a lower lip 31 formed, which in operation in contact with the extrudable mass 5 stands. To influence the contour of the mass to be extruded 5 to take is the lower lip 31 flexible execution. Below the flexible lower lip 31 are lower threaded holes 32 arranged, which actuators 7 , for example, executed as adjusting screws record.

Unless upper end bar 20 and subdivision end bar 30 have common features, they are also considered at least one bar 20 . 30 or strips 20 . 30 designated. Likewise, provided the flexible upper lip 21 and the flexible lower lip 31 Having common features, they are also called at least one flexible lip 21 . 31 or flexible lips 21 . 31 designated.

Each actuator 7 is in at least one threaded hole 6 positively and non-positively arranged. This will cause an adjustment of the flexible lips 21 . 31 allows. In its longitudinal extension, the actuating element 7 several threaded holes 6 pass through, for example, when due to material savings, the strips 20 . 30 be executed as U-profiles.

The 2 shows another setting of the flexible upper lip 21 compared to the position of the flexible upper lip 21 in the 1 , In the presentation of the 1 grants the flexible upper lip 21 in the area to the left of the center, seen in the material flow direction X, the largest passage for the extrudable mass 5 , On the other hand, in the presentation of the 2 a setting for the flexible upper lip 21 chosen in the middle or near the center of the flexible lips 21 . 31 the largest passage for the extrudable mass 5 consists.

The flexible lower lip 31 is located, just like in the 1 shown in their starting position. By adjusting at least one actuating element 7 will affect the contour of the mass to be extruded 5 as they pass through the die gap 4 taken. By doing that, the flexible lips 21 . 31 the last contact with the material flow of the extrudable mass 5 give it the final contour, except for the material-related shrinkage or expansion effects.

So that the extrudable mass lighter the flexible lips 21 . 31 can happen, these indicate their on the extrudable mass 5 facing side a lubricious coating 8th on.

The at least one flexible lip 21 . 31 is at least in the end 9 their length on at least one bar 20 . 30 set, the determination is done for example by a screw or welded connection. In the intermediate area is the at least one flexible lip 21 . 31 vertically movable to contour the flowing extrudable mass 5 to enable. For this purpose, the at least one flexible lip 21 . 31 designed as a metal strip. This metal strip is made of a metal or a metal alloy.

LIST OF REFERENCE NUMBERS

1

extruder head

2

top

3

lower part

4

die gap

5

extrudable mass

6

threaded hole

7

actuator

8th

slide coating

9

end

20

Oberteilendleiste

21

upper lip

22

Upper threaded holes

30

Unterteilendleiste

31

bottom lip

32

Lower tapped holes

X

Material flow direction

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 1704481 A [0002, 0002]
• US 2720679 [0003]
• US 3,195,183 [0003]
• DE 2305877 A [0004]

Claims (10)

Device for adjusting the outflow opening of an extruder head ( 1 ), wherein the extruder head ( 1 ) a top ( 2 ) and a lower part ( 3 ), wherein at the top ( 2 ) and at the lower part ( 3 ) one bar each ( 20 . 30 ) is formed, which a nozzle gap ( 4 ) for the passage of extrudable mass ( 5 ), characterized in that on at least one bar ( 20 . 30 ) in the outlet direction of the material flow of the extrudable mass ( 5 ) at least one flexible lip ( 21 . 31 ) for contouring the extrudable mass ( 5 ) and that the at least one flexible lip ( 21 . 31 ) with at least one actuating element ( 7 ) is in operative connection. Device according to claim 1, characterized in that the at least one flexible lip ( 21 . 31 ) at least in the end region ( 9 ) of its longitudinal extent force, form and / or material fit on at least one bar ( 20 . 30 ). Device according to one of the preceding claims, characterized in that the at least one actuating element ( 7 ) positively movable on the at least one bar ( 20 . 30 ) is stored. Device according to one of the preceding claims, characterized in that the at least one flexible lip ( 21 . 31 ) is made of metal or a metal alloy. Device according to one of the preceding claims, characterized in that the at least one flexible lip ( 21 . 31 ) is designed as a sheet metal strip. Device according to one of the preceding claims, characterized in that the at least one flexible lip ( 21 . 31 ) on its extrudable mass ( 5 ) facing side a lubricious coating ( 8th ) having. Device according to one of the preceding claims, characterized in that the at least one actuating element ( 7 ) is designed as an adjusting screw which in at least one threaded bore ( 6 ) is stored. Device according to one of the preceding claims, characterized in that on the top end bar ( 20 ) a flexible upper lip ( 21 ) and at the subdivision end bar ( 30 ) a flexible lower lip ( 31 ) is arranged. Method for operating a device for adjusting the outflow opening of an extruder head ( 1 ), characterized in that the contour of the out of the outflow opening of the extruder head ( 1 ) extruded material strand of extrudable mass ( 5 ) is matched with the target contour, whereupon the at least one flexible lip ( 21 . 31 ) in cooperation with at least one actuating element ( 7 ) for adjustment, preferably fine adjustment of the contour of the material flow (X) of the extrudable mass ( 5 ) is adjusted depending on the deviation to the target contour of the material strand. Method according to claim 9, characterized in that the adjustment of the at least one flexible lip by adjusting the at least one actuating element ( 7 ) during the extruder process.

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