AT522178A4 - Plasticizing device for a molding machine - Google Patents

Abstract

Plasticizing device (1) for a molding machine (2), in particular for an injection molding machine or transfer press, with a plasticizing cylinder (3), a plasticizing screw arranged in the plasticizing cylinder (3), rotatable about a longitudinal axis (L) and linearly movable along the longitudinal axis (L) (4), the plasticizing screw (4) having at least one functional area (5), a sensor (6) arranged in or on the plasticizing cylinder (3), with which the distance (D) to the surface of the at least one functional area (5) of the plasticizing screw (4) is measurable, and a detection device (7) for detecting the type (T) of the functional area (5) and / or the operating state (B) of the functional area (5), which is configured to do so by moving the functional area (5 ) to record a distance signal curve (V) relative to the distance sensor (6), to compare the recorded distance signal curve (Vist) with a stored distance signal curve (Vref) and to output a signal (ST, SB) representing the type (T) of the functional area (5) and / or the operating state (B) of the functional area (5) as a function of a match between the detected distance signal profile (Vist) and a stored distance signal profile (Vref).

Description

The invention relates to a plasticizing device, a molding machine, in particular for an injection molding machine or transfer press, with a plasticizing cylinder, a plasticizing screw arranged in the plasticizing cylinder, rotatable about a longitudinal axis and linearly movable along the longitudinal axis, the plasticizing screw having at least one functional area, and one in or on the plasticizing cylinder arranged sensor with which the distance to the surface of the at least one functional area of the plasticizing screw can be measured. The invention also relates to a shaping machine with such a plasticizing device and a method

for operating a plasticizing device.

Different functional areas are used in the shaping process depending on the requirements. Functional areas can be, for example, a non-return valve, a screw flight zone of the plasticizing screw, a mixing head or a mixer. Depending on the type of functional area used, certain processing parameter limits or recommendations must be observed. The disadvantage is that the functional area for the operator after installation

is no longer understandable.

DE 10 2011 103 810 A1 discloses a plasticizing unit with a wear sensor. A signal is output via an evaluation unit as soon as the distance between the plasticizing cylinder and plasticizing screw measured by a measuring sensor has reached a definable limit value. A wear curve can also be displayed. With this system, therefore, conclusions can only be drawn about the wear on the plasticizing screw, without a direct one

To have a look inside the plasticizing cylinder.

The object of the present invention is therefore to create a plasticizing device which is improved over the prior art. In particular, the known disadvantages should be avoided. Above all, a possibility for better analysis should be created without having to dismantle the plasticizing screw

have to.

to have to remove the plasticizing screw.

Preferred embodiments are given in the dependent claims.

Functional areas are all those areas of a plasticizing screw or a part that is not visible in the plasticizing cylinder and that fulfill a specific function during the plasticizing and injection process. Specifically, a non-return valve, a screw flight zone of the plasticizing screw or a mixer form such a functional area. The functional area can also be used as a component for performing a work step

are designated.

The distance signal profile can in itself represent the profile of the distance from the (distance) sensor to any section and to any component of the functional area. It is preferably provided that the distance signal curve represents the surface contour of the functional area. This means that the surface of the functional area is scanned and a distance signal profile is created from it. The type of the functional area itself results from the (recorded) form of the functional area. The surface contour

thus serves as a type identification means.

Alternatively (or additionally) it can be provided that as identification means for

Recognizing the type of functional area one trained in the functional area

Functional area, be lasered.

With the detection device, however, not only the type, but alternatively or additionally the operating state of the functional area can be determined. An operating state can be, for example, the switch position of the functional area. With reference to the functional area in the form of a non-return valve, for example, a distinction can be made between the switch position “closed” and “open”. On the basis of the distance signal curve, it can therefore be concluded whether the non-return valve is currently open or closed and a corresponding signal can be output. The movements of the locking ring or the oscillation (orbital movement) of the tip can also be recorded in order to identify the operating status of the plasticizing screw. If the process parameters are not set optimally, they oscillate

Plasticizing screw or thus the lock in the cylinder.

It is also possible for the detection device to measure, for example, the closing of the non-return valve (e.g. shortening of the tip wings) or the length of the locking ring. Likewise, the number of in the non-return valve

balls used can be determined.

The type or the operating status does not have to be identified in every cycle. The detection device can for example be configured in such a way that the type of functional area and / or is detected only after a machine stop or after a standstill that lasts longer than a predetermined time

the operating status of the functional area takes place.

From the determined type of functional area and / or operating state

a specification or recommendation of processing parameters for the optimal

Components with regard to the suitable plastics.

The recorded data enable production data to be recorded. In particular, this can be used to calculate a collective load (accumulated load). In this way it can be calculated how long a non-return valve has produced with different parameters. This also enables preventive maintenance: when a certain working time has been reached, maintenance can be carried out again. This allows the maintenance intervals to be controlled. Above all, there are variable,

Maintenance intervals adjusted to the actual consumption.

According to a preferred exemplary embodiment, it is provided that the stored distance signal curve is stored in a memory of the plasticizing device

or can be called up from a cloud via a data line.

Furthermore, it is preferably provided that the detection of the distance signal profile when the plasticizing screw rotates (around the longitudinal axis), when the plasticizing screw is linearly movable along the longitudinal axis or when it is rotating and translationally

(along the longitudinal axis) movable plasticizing screw takes place.

The stored distance signal profile can be based on a distance signal profile specified for the functional area. This means that when the plasticizing screw is installed, a reference distance signal curve that matches the functional area or the functional areas is stored. This can be provided by the manufacturer of the plasticizing screw. Alternatively, it is possible that after the assembly of the plasticizing screw a one-time

Discovery run is performed. A distance signal course (graph)

will.

The following components or areas can form specific functional areas:

- In the case of a functional area in the form of a non-return valve, the type of functional area is a ball lock, a wing lock, a link lock, a multi-ball lock or a ring non-return valve.

- In the case of a functional area in the form of a spiral flight, the type of functional area is a single-flight screw, a barrier screw, a double-flight screw, a metering zone, a compression zone or a feed zone.

- In the case of a functional area in the form of a mixer, the type of functional area is a toothed disk mixer, a diamond mixer

Shear mixing head, a shear part, a spiral shear part or a Maddock mixer.

The measurement of the distance can be carried out with any suitable sensor. It is preferably provided that the sensor is used as a sound sensor (preferably as an ultrasonic sensor), as an electromagnetic sensor or as a capacitive sensor

is trained.

Furthermore, it is preferably provided that the sensor has at least one measuring head. At least two, along the longitudinal axis or, are particularly preferred

measuring heads spaced apart from one another are provided along the circumference.

The at least one measuring head can be located inside the plasticizing cylinder. It can also be arranged at a distance from the plasticizing cylinder. However, it is preferably provided that the at least one measuring head is arranged on the plasticizing cylinder, preferably on the outside of the plasticizing cylinder, particularly preferably in a blind bore formed on the outside of the plasticizing cylinder. Even if two measuring heads are provided

are, they can each be arranged in a blind hole.

Be a molding machine.

The detection device can be designed as part of the control or regulation unit. Alternatively, the detection device with the control or regulation unit in

signaling connection.

Protection is also desired for a molding machine with a

plasticizing device according to the invention.

The above-described object is also achieved by a method having the features of claim 15. Accordingly, the invention provides that the type of functional area and / or the operating state of the functional area is recognized by the steps of moving the functional area relative to the distance sensor, acquiring a distance signal curve, comparing the recorded distance signal curve with a stored distance signal curve and outputting the type of the functional area and / or the operating state of the functional area representing signal as a function of a match of the detected

Distance signal course with a stored distance signal course.

Further details and advantages of the present invention will become apparent from the description of the figures with reference to those shown in the drawings

Exemplary embodiments are explained in more detail below. Show in it:

Fig. 1 is a schematic side view of a molding machine with a plasticizing device, Fig. 2-3 sections through the plasticizing cylinder in different positions

the plasticizing screw along the longitudinal axis,

7728

7 shows a diagram with an exemplary distance signal curve,

8 shows a schematic section through a plasticizing cylinder and a plasticizing screw,

FIG. 9 shows a diagram with a distance signal curve matching FIG. 8,

10a-10c various representations of a non-return valve in the form of a single ball lock,

11a-11c different representations of a non-return valve in the form of a central ball lock,

12a + 12b various representations of a non-return valve in the form of a

Multi-wing lock, FIG. 13 a cross section matching FIGS. 10a to 10c, FIG. 14 a cross section matching FIGS. 11a to 11c, FIG. 15 a cross section matching FIGS. 12a and 12b, FIG. 16a a front view matching 10c, 16b show a diagram with a distance signal profile matching FIG. 16a, FIG. 17a a front view matching FIG. 11c, FIG. 17b a diagram with a distance signal profile matching FIG. 17a, FIG. 18a a front view matching FIG FIGS. 12c and 18b show a diagram with a distance signal profile that matches FIG. 18a.

In Fig. 1, a shaping machine 2 is shown in a schematic side view. This shaping machine 2 has a clamping unit 11 (shown on the left). This clamping unit 11 comprises a movable platen 12, a stationary platen 13, a mold 14 mounted on the platen 12 and 13 and a drive device 15 (for example in the form of a toggle system) for the movable platen 12. In the closed mold 14 is

at least one cavity K is formed. The molding machine 2 has (shown on the right) a plasticizing device 1

on. This plasticizing device 1 comprises a plasticizing cylinder 3 and an im

Plasticizing cylinder 3 arranged, rotatable about a longitudinal axis L and along the

K to at least one shaping part (injection molded part).

The plasticizing screw 4 has at least one functional area 5. In Fig. 5 three exemplary functional areas 5 are shown - a non-return valve 5a, a mixer 5b and a screw flight zone 5c. A measuring head 6a of a sensor 6 is assigned to each of these functional areas 5. Together with one

Evaluation unit 6b, each measuring head 6a forms a sensor 6.

The plasticizing device 2 has a detection device 7 for detecting the type T of the functional area and / or the operating state B of the functional area 5. By moving the functional area 5 relative to the sensor 6, a distance signal curve V is recorded by the sensor 6. Specifically, the measuring head 6a of the sensor 6 records the distance D to the surface of the functional area 5. During the movement of the plasticizing screw 4 relative to the plasticizing cylinder 3, a new value of the distance D is recorded at regular time intervals (e.g. in the millisecond range). The total recorded measured values of the distance D result in a recorded distance signal profile Viss. This detected distance signal profile Vist is compared with at least one (preferably in a memory 8) stored distance signal profile V, ef. Depending on whether the detected distance signal profile Viss corresponds to a stored distance signal profile V, e: a signal St or Sg representing the type T of the functional area 5 and / or the operating state B of the functional area 5 is generated

issued.

The plasticizing device 1 has a control or regulating unit 10. The detection device 7 is in signaling connection with this control or regulation unit 10. The type T or the is preferred

Operating state B representing signal St or Sg to this control or

represent.

2 shows a section through a plasticizing cylinder 3 with a plasticizing screw 4. The plasticizing cylinder 3 has a flange 21. Blind bores 9 are formed on the inside of the plasticizing cylinder 3. A measuring head 6a of a sensor 6 is arranged in each of these blind bores 9. The functional area 5 is designed as a non-return valve 5a. The non-return valve 5a has the locking ring 20, the stop 22 (in this case a pressure ring) and several balls 23 (in this case bearing balls). The plasticizing screw 4 is currently moving forward, which is indicated by the movement arrow P. At the same time, there is also a rotary movement about the axis of rotation of the plasticizing screw 3 (see movement arrow R). The measuring head 6a is

the distance D is recorded at time t +.

In Fig. 3 a section is shown again through the same plasticizing cylinder 3, wherein the plasticizing screw 4 has already moved further forward. In this case, no second measuring head 6a is shown. The measuring head 6a arranged in the plasticizing cylinder 3 determines the distance D between the surface of the

Functional area 5 recorded at time t2.

In the same way, according to FIG. 4, the distance D between the surface of the functional area 5 is detected at the point in time tz. With the position according to FIG. 4, the forward movement of the plasticizing screw 4 is completed. But it is still happening

another turning movement.

A radial cross section through the plasticizing cylinder 3 together with the plasticizing screw 4 is shown in FIG. The balls 23 of the non-return valve 5a can be seen, which are arranged at regular intervals from one another around the plasticizing screw 4. The measuring head 6a measures the distance D to

Surface (specifically to the locking ball 23) of the functional area 5 at the time t4.

According to FIG. 6, the plasticizing screw 4 has continued to rotate through the angle W. As a result, the distance D between the measuring head 6a and the

Functional area 5 enlarged. This distance D corresponds to the point in time ts.

The detected distances D at the times t4 to ts are combined by the detection device 7 to form a distance signal curve V. An exemplary distance signal profile V is illustrated in the diagram according to FIG. 7. The ordinate of this diagram shows the distance D detected by the sensor 6. The abscissa of this diagram shows the time t. The distances D at the various times t + to ts are given by way of example. This distance waveform V can be a detected distance waveform Vist or a

deposited distance signal curve V, e: correspond.

In other words, FIGS. 2 to 7 can be described as follows: When the plasticizing screw 4 moves forwards or backwards, a measuring range of a sensor 6 is swept over. The sensor 6 can be mounted in the flange 21 or in the plasticizing cylinder 3. The sensor 6 can be designed as an ultrasonic sensor. During the axial movement, the distances D to the contour of the screw tip and the associated components are measured and recorded. The signal obtained corresponds to the distance D to a reflection surface or topography on one or more components of the plasticizing screw 4 (e.g. non-return valve 5a or mixing parts). During the movement, the distance signal curve V results as a function of time t, the position along the longitudinal axis L and the angle W, which is normalized with the speed. Depending on the basic shape of the functional area 5, a characteristic curve results which can be clearly assigned to the type T of the functional area 5. To compare the characteristic distance signal curves V, these are shown in

Dependence on the position during the course of time and the speed ins

Relationship is set and the graphs obtained in this way are superimposed by

compared.

In Fig. 8 a schematic section through a plasticizing cylinder 3 and a plasticizing screw 4 is shown. The plasticizing screw 4 has a functional area 5 in the form of a screw flight zone 5c. This screw flight zone 5c has one or more, helically around the

Plasticizing screw 4 coiled screw flights 24.

When the plasticizing screw 4 according to FIG. 8 moves in the direction of the movement arrow P and / or when the plasticizing screw 4 rotates about the longitudinal axis L, the sensor 6 detects a distance signal curve Vist. This is illustrated in FIG. 9. The elevations in the distance signal curve Viss correspond to the groove-shaped screw flights 24, since there the distance D to the sensor 6 is greater than in the area of the screw flights 25. The recorded distance signal curve Viss produces a characteristic signal which is compared with the stored distance signal curves Vrer. The recognized type T of the functional area 5 is output as a function of a match. Stored distance signal curves V, e: can be found in

stored digitally in a kind of library.

FIGS. 10a, 10b and 10c show different representations of a non-return valve 5a. FIG. 10a shows a side view, FIG. 10b shows a cross section and FIG. 10c shows a front view. In this case, the non-return valve 5a is a so-called single-ball lock with a single (locking) ball 23 and a locking ring 20

educated.

In contrast, FIGS. 11a (side view), 11b (cross section) and 11c (front view) show a non-return valve 5a in the form of a central ball lock. Here the ball 23 together with the ball seat forms a ball valve. This non-return valve 5a has several regularly around the longitudinal axis L in the region of the screw tip 27

arranged outflow openings 26.

12a (cross section) and 12b (front view) show a ring non-return valve 5a in the form of a multi-vane barrier. In this case, the multi-leaf lock will redirect three

the longitudinal axis L arranged, regularly spaced wings 28 on.

Fig. 13 shows a non-return valve 5a according to FIG. 10b, which in a

Plasticizing cylinder 3 is arranged.

Fig. 14 shows a non-return valve 5a according to FIG. 11b, which in a

Plasticizing cylinder 3 is arranged with a measuring head 6a.

15 shows a non-return valve 5a arranged in the plasticizing cylinder 3

according to Fig. 12a.

16a shows the front view according to 10c and schematically of the measuring head 6a. During the rotation of the plasticizing screw 4, the measuring head 6a scans the functional area 5 - in this case the surface of the non-return valve 5a designed as a central ball lock. This results in the characteristic distance signal curve Vist according to FIG. 16b. The increases in the distance signal curve Viss correspond to the lateral flattened areas 29 on the

Non-return valve 5a.

In contrast, FIG. 17a shows the front view according to FIG. 11c. By scanning the surface with the measuring head 6a (as indicated in FIG. 14), the distance signal curve Visı according to FIG. 17b results. The regularly arranged elevations in which the distance D is greater and which is clearly visible are clearly visible

individual outflow openings 28 in the screw tip 27 correspond.

18a shows the front view according to FIG. 12b of a non-return valve 5a in the form of a multi-vane barrier. In the detected distance signal curve Vist shown in FIG. 18b, the elevations correspond to the notches between the blades 28 of FIG

Snail tip 27.

List of reference symbols:

1 plasticizing device

6a 6b

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29

13

Forming machine plasticizing cylinder plasticizing screw functional area non-return valve

mixer

Worm gear zone

sensor

Measuring head

Evaluation unit recognition device

Storage

Blind hole

Control or regulation unit, clamping unit

movable platen fixed platen molding tool drive device for movable platen drive device for plasticizing screw screen

Filling funnel

Injection port

Locking ring

flange

attack

Balls (locking ball or bearing balls) screw flights screw flights outflow openings screw tip

wing

lateral flattenings

Longitudinal axis

D distance

T Type of functional area

B Operating state of the functional area V Distance signal curve

Vist detected distance waveform

Vrer deposited distance signal curve

St type representing signal

Se operating state representing signal P movement arrow

R movement arrow

W angle

Innsbruck, April 25, 2019

Claims (1)

Claims 1. Plasticizing device (1) for a molding machine (2), in particular for an injection molding machine or transfer press, with - a plasticizing cylinder (3), - A plasticizing screw (4) arranged in the plasticizing cylinder (3), rotatable about a longitudinal axis (L) and linearly movable along the longitudinal axis (L), the plasticizing screw (4) having at least one functional area (5), and - A sensor (6) arranged in or on the plasticizing cylinder (3), with which the distance (D) to the surface of the at least one functional area (5) of the plasticizing screw (4) can be measured, marked by - A recognition device (7) for recognizing the type (T) of the functional area (5) and / or the operating state (B) of the functional area (5), which is configured by moving the functional area (5) relative to the distance sensor (6 ) to record a distance signal waveform (V), compare the recorded distance signal waveform (Vist) with a stored distance signal waveform (V, er) and, depending on whether the recorded distance signal waveform (Vist) matches a stored distance signal waveform (Vrer), enter the type (T) of the functional area (5) and / or the operating state (B) of the functional area (5) representing signal (ST, Se) output. 2. Plasticizing device according to claim 1, characterized in that the functional area (5) has a non-return valve (5a), a screw thread zone (5c) the plasticizing screw (4) or a mixer (5b). 3. Plasticizing device according to claim 1 or 2, characterized in that the distance signal curve (V) the surface contour of the functional area (5) represents. in the functional area (5) trained surface code acts. Plasticizing device according to one of Claims 1 to 4, characterized in that the detection of the distance signal curve (V) when the plasticizing screw (4) is rotating, when the plasticizing screw (4) is linearly movable along the longitudinal axis (L) or when the plasticizing screw (4) is rotating and translational movable plasticizing screw (4) takes place. Plasticizing device according to one of claims 1 to 5, characterized in that the stored distance signal curve (V, er) is stored in a memory (8) of the plasticizing device (1) or via a Data line can be accessed from a cloud. Plasticizing device according to one of Claims 1 to 6, characterized marked that - in the case of a functional area (5) in the form of a non-return valve (5a), the type (T) of the functional area (5) is a ball lock, a wing lock, a link lock, a multi-ball lock or a ring non-return valve, - In the case of a functional area (5) in the form of a screw flight zone (5c), the type of functional area (5) is a single-flight screw, a barrier screw, a double-flight screw, a metering zone, a compression zone or a feed zone, - In the case of a functional area (5) in the form of a mixer (5b), the type of functional area (5) is a toothed disk mixer, a diamond mixer, a shear mixing head, a shear part, a spiral shear part or a Maddock Mixer is. Plasticizing device according to one of Claims 1 to 7, characterized in that the sensor (6) is a sound sensor, preferably an ultrasonic sensor, an electromagnetic sensor or a capacitive sensor is trained. 11. 12. 13. 14th 15th Plasticizing device according to one of claims 1 to 8, characterized in that the sensor (6) has at least one measuring head (6a), preferably at least two, along the longitudinal axis (L) or along the Circumferentially spaced measuring heads (6a). Plasticizing device according to claim 9, characterized in that the distance sensor (6) is connected to the measuring head (6a) Has evaluation unit (6b). Plasticizing device according to claim 9 or 10, characterized in that the at least one measuring head (6a) on the plasticizing cylinder (3), preferably on the outside of the plasticizing cylinder (3), particularly preferably in a blind hole (9) formed on the outside of the plasticizing cylinder (3) ), is arranged. Plasticizing device according to one of Claims 1 to 11, characterized by a control or regulating unit (10) for controlling or regulating Movements of the plasticizing screw (4). Plasticizing device according to claim 12, characterized in that the detection device (7) forms part of the control or regulating unit (10) or is in signaling connection with the control or regulating unit (10). Molding machine (2) with a plasticizing device (1) according to one of the Claims 1 to 13. A method for operating a plasticizing device (1) of a molding machine (2), in particular an injection molding machine or transfer press, the plasticizing device (2) having - a plasticizer cylinder (3), - one arranged in the plasticizing cylinder (3) around a longitudinal axis (L) rotatable and linearly movable along the longitudinal axis (L) - A sensor (6) arranged in or on the plasticizing cylinder (3), with which the distance (D) to the surface of the at least one functional area (5) of the plasticizing screw (4) can be measured, characterized in that a recognition of the type (T) of the Functional area (5) and / or the operating state (B) of the Functional area (5) is carried out through the steps - Moving the functional area (5) relative to the sensor (6), - Acquisition of a distance signal curve (V), - Compare the detected distance signal profile (Vist) with a stored distance signal profile (V, er) and - Output of a signal (ST, Se) representing the type (T) of the functional area (5) and / or the operating state (B) of the functional area (5) depending on whether the detected distance signal profile (Visp) matches a stored distance signal profile (Vref) - Innsbruck, April 25, 2019