KR20070092448A - Devices for dispensing non-Newtonian liquids along passages - Google Patents

Abstract

The present invention is a non-Newton, such as molten synthetic material flowing along passages (1, 21), having a viscosity that gradually decreases outward in cross section of the flow flowing along the T-shaped passage branch (T), which directs and distributes the liquid flow. (non-Newtonian) relates to a device for dispensing liquids. In the first embodiment of the apparatus, before one end of the supply passage 1, the partition 11 is installed inside the passage branch T, which serves to distribute the liquid flowing back from the supply passage 1 in half and , The angular position of the partition 11 is set to separate and distribute the viscous components of the liquid flowing into the supply passage 1. In the second embodiment of the apparatus, the current transformer 23 is installed inside the passage branch T so that the central component (viscosity) of the liquid substance supplied from the supply passage 21 before the flow of the flow into the discharge passages 22a and 22b. Component) substantially in two components, and these two components are flown so as to flow radially, preferably in front of the discharge passages 22a, 22b, respectively.

Description

DEVICE FOR DIVISION OF A NON-NEWTONIAN LIQUID FLOWING THROUGH A PASSAGE}

1A-1C show the flow of non-Newtonian liquid inside a cylindrical passage.

2 illustrates a passage manifold system with three T-shaped passage branches.

2A is a top view of a portion of FIG. 2.

3a to 3c show the symmetrical distribution of viscous and fluid liquid components behind the first channel branch T1.

4A-4C show the distribution of the melt flowing from the first passage branch T1 to the passage branch T2 in the same plane as the previous passage branch T1.

5a to 5c show the distribution corresponding to FIG. 4 in a subsequent passage branch T3 located in a plane perpendicular to the previous passage branch T1.

6a and 6b show in principle a first embodiment of the invention for a first type of device.

FIG. 7 shows a practical embodiment in which the first type of device shown in FIG. 6 is installed inside a T-shaped passage branch.

8A and 8B are perspective views of an embodiment of the partition plug shown in FIG. 7.

9A and 9B are perspective views of a second type of embodiment according to the present invention, in two sections installed inside a T-shaped passage branch and perpendicular to each other.

10A and 10B show an embodiment in which a fixing part is added to the current transformer shown in FIGS. 9A and 9B in a direction perpendicular to each other.

11 shows the current transformer according to FIG. 10 installed inside the T-tube.

* Explanation of symbols for the main parts of the drawings

1: supply passage 2a, 2b: discharge passage

10: partition plug 11: partition 12: bore

14 screw plug 16: dome shaped depression

21: supply passage segment 22a, 22b: discharge passage segment

23: Current transformer 24: Blade 27: Web

31: cylindrical segment

The present invention relates to a device for the precise distribution of non-Newtonian liquids through a passage.

In injection molding, a molten synthetic material, such as a thermoplastic, is passed through, for example, a hot passage manifold system with branches at any location, and the melt supplied in one passage is distributed between the two discharge passages. . This branch mainly has a T-shaped structure.

In the case of Newtonian liquids passing through a circular passage, the parabolic flow rate distribution of the liquid is subdivided into imaginary concentric hollow cylindrical layers, with the flow rate maximizing at the center of the passage. In such liquids the shear stresses between the plurality of virtual hollow cylindrical cylindrical layers are approximately equal.

On the other hand, non-Newtonian liquids, for example (hot) liquid plastics, behave differently. In this case, the viscosity depends on the shear stress, which is maximum near the wall of the circular passage. The smaller the viscosity, the greater the shear stress. As a result, the viscosity near the wall of the circular passageway is minimal. The viscous distribution of the melt over the cross section of the circular passage is similar to a rapidly flat parabola. In simple terms, this means that the melt, seen as a viscous fluid in the central region of the passage, behaves like a plug with a flow rate that is almost independent of its radial position, while in the peripheral region of the passage the melt has a larger shear The closer to the fluid and the slower the flow because of the stress.

This behavior is shown in Figures 1A-1C. 1A shows a circular passage through which a non-Newtonian liquid, for example a plastic melt, flows. FIG. 1B shows the distribution of flow rate V over the cross section, and FIG. 1C shows the distribution of shear stress. Region d almost corresponds to the plug described above.

If the non-Newtonian liquid flow of the type shown in FIG. 1 is distributed inside a rectangular (T-shaped) branch T1 and divided into two separate flows S1 and S2 as shown in FIG. 2, the high point of the liquid The male and fluid portions will be distributed over the cross section of the passage. The distribution over the cross section is shown in FIGS. 3A-3C, where the HV region represents a high viscosity liquid and the LV region represents a low viscosity liquid. In the coordinate system shown in Figs. 2 to 5, the x and y axes are located in the plane of the drawing, and the z axis is perpendicular to the plane of the drawing. Thus, the highly viscous HV portion of the non-Newtonian liquid will gather substantially under the passage segment 2a, 2b shown in FIG. This is easy to see, because the viscous fluid (melt) supplied from the central region of the passage segment 1 will proceed to the lower part of the T tube 6 and then to the left and right as indicated by the arrow "a" in FIG. Will flow. On the other hand, the liquid close to the fluid flowing through the peripheral region of the passage 1 will flow left and right from the starting point of the branch of the passage as indicated by the arrow "b".

If the passage segments 2a and 2b shown in Fig. 2 are very long, the natural distribution shown in Fig. 3A will gradually recover. However, since the passage segment is actually short in length, the distribution shown in FIGS. 3B and 3C will be maintained almost until the next branch in the T tube.

If the liquid flowing inside the passage segment 2a encounters the T-shaped tube T2 whose longitudinal axis is in the y-axis direction, the distribution in the discharge passages 3a and 3b is as shown in FIG. Here, the figures are shown in the flow direction of the present discharge passage. In the discharge passage, noticeable disproportionate distribution of the viscous and fluid portions and their pronounced asymmetry with respect to the center of the passage can be seen.

The T-tube T3 in FIG. 2 has two discharge passages 4a and 4b extending perpendicular to the plane of the drawing (z direction). FIG. 2A is a top view of the portion T3 of FIG. 2. FIG. After the flow in the T-tube T2, the state of separation of the viscous and fluid portions of the liquid is shown in Figs. 5A and 5B. The distribution in the discharge passage 4b lying in the direction exiting from the plane of FIG. 2 is shown in FIG. 5C, and the distribution in the discharge passage 4a lying in the direction entering from the plane of FIG. 2 is shown in FIG. 5B, The figure is shown in the flow direction of the discharge passage.

In injection molding, if the injection nozzles connected to the injection molding apparatus (mold) have a passage and / or a distribution in which the quantitative distribution of melt components having different viscosities are different, as shown in Figs. 4b and 4c, If supplied from a passage which is no longer symmetrical in the direction of rotation with respect to the longitudinal axis of the passage, as in FIGS. 3B and 5B, this may cause a defect in the cast injection molded article.

If the plate is ejected through a plurality of nozzles distributed in the plate area, the following defects may occur.

If the fluid melt from the nozzles in the outer region of the plate is more than the fluid melt from the nozzles in the inner region of the plate, the incoming melt is subjected to temporary pressure, causing more melt in the outer region than the middle region of the plate. It is pushed into the injection mechanism (injection mold). This means that more material per unit area is supplied to the plate in the outer region than in the inner region, which results in the casting plate having irregular edges. Conversely, if more fluid melt is pushed into the injection mold in the inner region, after cooling of the melt, there will be more melt per unit area in the inner region resulting in expansion in the inner region of the plate.

Although not a big problem, a similar situation can occur if the melt inside the passage segment feeding the nozzle is distributed asymmetrically.

If each of the plurality of injection nozzles of the hot passage manifold system injects the cup, an uneven quantitative distribution of viscous melt and fluid melt passing between the plurality of nozzles will result in different cup thicknesses. The asymmetric distribution of the melt components results in that one side of the cup contains a thicker fluid melt than the opposite side, resulting in a convex cup shape, or where the viscous melt is inserted into the mold. You will not be able to reach the bottom.

It is an object of the present invention to provide an apparatus for minimizing or possibly eliminating as much as possible asymmetric and / or uneven quantitative distributions of liquid components having different viscosities by means of the above-mentioned flow action.

To achieve this object, a first embodiment of an apparatus for accurately dispensing non-Newtonian liquid, for example molten synthetic material, passing through passage 1 may be provided. The material has a viscosity that gradually diminishes outwards in the cross section of the flow flowing through the T-shaped passage branch T, which flows and distributes the liquid flow. The partition lies inside the passage branch T, which causes the liquid flowing back from the feed passage segment 1 to be divided in half. The angular position of the partition 11 is preferably set to distinguish and distribute the viscous components of the liquid flowing into the feed passage segment 1. According to the present invention, the viscous components of the liquid are not significantly distinguished and distributed between the discharge passages 2a and 2b of the passage branch T.

According to an embodiment of the invention, preferably or substantially within the feed passage segment of the T-shaped passage branch, melt components with different viscosities are distributed asymmetrically in the direction of rotation. Instead, the proportion of melt components with different viscosities inside the two outlet passage segments of the passage branch are substantially the same.

In a second embodiment of the invention, a current transformer is provided for distributing the flow of material.

In a second embodiment of the apparatus, preferably or substantially within the feed passage segment of the T-shaped passage branch, the quantitative distribution of melt components with different viscosities is symmetric in the direction of rotation. Within the two outlet segments of the passage branch, in particular in a rotational direction, a symmetrical distribution is maintained, and the proportion of melt components with different viscosities in the two outlet passages is substantially the same. Thus, the distribution pattern in the outlet passage segment is essentially the same as that in the feed segment.

The discharge passages can have the same cross-sectional area as that of the feed passage, so that the flow rate inside the discharge passages is cut in half. Optionally, however, the discharge passages can have a smaller cross-sectional area so that the flow rate decreases less rapidly or does not decrease at all.

6a and 6b show in principle an embodiment with a structure of the first type of the device according to the invention. Since the partition 11 facing the feed melt is installed inside the passage branch, it is possible to distribute the melt flow supplied from the feed passage segment 1. Here, the partition 11 is placed so as to be rotatable to distribute the approaching melt, where the liquid components with different viscosities are not symmetrically distributed in the direction of rotation with respect to the longitudinal axis of the passage, Rotatable partitions can be used to create flows that contain liquid components with different viscosities evenly.

If the partition 11 is absent, the melt distributes itself between the outlet passages corresponding to the line “t” shown in FIG. 6A, but if there is a partition 11 placed in the angular position shown in FIG. 6B, the approaching melt Can separate the viscous and fluid liquids into the two outlet passages at the same rate. The partition 11 may be arranged in a manner suitable for an adjustable fixed position or an angular position inside the passage branch.

An embodiment according to the invention is shown in FIGS. 7 and 8. In FIG. 7, a bore 12, starting from the bottom 6 of the T-shaped passage branch, is made inside the T-tube. In this bore 12, the partition plug 10 with the partition 11 firmly attached is pressed down to the center of the discharge passage segments 22a and 22b. Here, the partition plug, such as the hexagon socket 13, can rotate to the desired angular position as shown in FIG. 6B. In order to prevent the plug 10 from being pushed under operating pressure, the plug 10 is fixed in an axial position by a screw plug 14, which screw plug 14 is for example. By means of the hexagon socket 15, it can be fixed using a screw inside the bore 12. The plug 10 is preferably a rigid object, the end of which is near the partition 11 in a dome-shaped depression 16, away from the supply passage segment 1 of the partition 11. The surface portion corresponding to the separated side is firmly fixed in any way inside the depression 16. The required angular position of the partition 11 is determined by the rotational position at which the partition plug 10 is inserted into the bore 12. This angular position may be maintained by any conventional method, such as a press fit or other additional suitable rotational fixing means.

Suitably, after the above-described plug is installed inside the passage branch, it is drilled in the dome-shaped depression 16 area to fit the diameter of the discharge passages in the partition plug 10 starting from the discharge passages 22a and 22b. This forms the projected hemispherical flow openings 17. Such flow openings can of course be provided before installation of the partition plug.

In FIG. 7, clearly, the partition 11 is placed at an angular position perpendicular to the plane of the figure, and the openings 17 formed by boring are placed in the plane of the figure. In practice these flow openings 17 are rotated 90 degrees, while the angular position of the partition 11 is defined with respect to the plane of the drawing, as shown in FIG. 6B, which is mutually in the supply passage 1. It will be appreciated that it can be adapted to the distribution of liquid components with different viscosities.

In FIG. 7, the underside 6 of the passage branch is shown with a stiffener 18. This is only necessary when the walls of the commercial T-tubes, ie the walls of the hot passage manifold blocks with flow, do not have sufficient thickness.

8A and 8B show a perspective view of the solid partition plug 10 as an example described above with the partition 11. 8A shows the plug 10 with the rear hex socket 13 before being drilled in the dome shaped recess 16 area. 8b shows a properly perforated plug after installation and the resulting flow openings 17.

In a second embodiment of the device according to the invention, the aim is to achieve this symmetrical distribution even when the liquid components with different viscosities inside the passage branch have a symmetrical distribution as shown in FIG. Is substantially maintained inside the discharge passage.

If it is assumed in FIG. 9B that the liquid inside the feed passage segment 21 is distributed as in FIG. 3A, the distribution inside the outlet passage segments 22a and 22b will be consistent with FIGS. 3B and 3C if there is no device. However, if a uniform liquid flow from the pipe 21, indicated as top in the figure, is sent to the passage branch with additional liquid flow at the bottom, the viscous fluid component flowing side by side inside the passages 22a and 22b in FIG. The virtual additional liquid flow will move towards the center of the passages 22a and 22b.

This can be done by a device of the second type of the invention having a conventional passage branch. In a second type of device according to the invention, a viscous liquid component flowing in the center of the feed passage segment is dispensed, the two components are flown at the inlet of the outlet passage segment and meet each other at substantially right angles, with the flow direction being It is essentially perpendicular to the longitudinal direction of the discharge passage.

To this end, a current transformer 23 inside the passage branch enters the feed passage segment 21 together with the blades 24 and essentially separates the viscous liquid component flowing in the center of the passage segment 21 into two components. . One flows to the left side of the current transformer 23 and the other flows to the right side. These components are deflected and meet at right angles on the underside 7 of the passage branch in the figure.

The web 27 where the two viscous components collide laterally serves only as a mechanical connection of the current transformer 23 inside the passage branch. The web 27 is not necessary for the practice of the present invention. The actual current transformer 23 preferably does not contact the passage segment 21 anywhere.

10A and 10B show an embodiment of the current transformer 23. The aforementioned web 27 is connected to a cylindrical segment 31 which leads to a cylindrical segment 32 having an expanded diameter. Together with the segment 31 described above, the current transformer 23 is inserted to the position shown in FIGS. 9A and 9B and secured in a sealed form through a bore at the bottom of the passage branch.

In principle, although difficult in small diameter passages, any fixture such as, for example, a strut 28, indicated by the dashed line in FIG. 9A, may be used as a current transformer 23 fixture inside the passage branch. .

The current transformer 23 comprising the web 27 and the cylindrical segment 31 can be fabricated from an integral cylinder, the front end having the blades 24 and the rear end forming the web 27 by notches on both sides. It has a contraction part, and is facing each other in parallel with the blade 24. The opposite side 25 of the current transformer extends from the blade 24 to the web 27 and is preferably located on a circular or similar curved surface and transitions to the surface of the cylinder 31.

FIG. 11 shows a current transformer of the same type as FIG. 11 installed inside the T-shaped passage branch. If the signs in Fig. 11 coincide with the signs in Figs. 9 and 10, they specify the same object.

As described above, the dispensing device of the present invention can minimize or possibly eliminate the asymmetric and / or uneven quantitative distribution of liquid components having different viscosities by the action of current flow, and also prevents their occurrence. It will be possible to reduce defects in injection molded products which can occur when the melt distribution is asymmetric.

Claims (16)

A device for dispensing non-Newtonian liquid material flowing along a passage (1), The material has a viscosity that gradually decreases outward in the cross section of the flow flowing through the substantially T-shaped passage branch T, which directs and distributes the liquid flow, The apparatus includes a partition positioned adjacent to the end of the supply passage of the passage branch (T) for dividing the liquid flowing back from the supply passage segment (1) in half, The angular position of the partition 11 is set to distinguish and distribute the viscous components of the liquid flowing into the feed passage segment 1, And the viscous components of the liquid flowing into the discharge passage are not substantially divided and distributed. The method of claim 1, The partition (11) is characterized in that the adjustment of the angular position. The method of claim 1, The partition 11 is located inside the passage branch T by a partition plug 10, and the partition 11 is opened by a bore 12 inside the passage branch T. Apparatus characterized in that it is attached to the partition plug (10). The method of claim 2, The partition 11 is located inside the passage branch T by a partition plug 10, and the partition 11 is opened by a bore 12 inside the passage branch T. Apparatus characterized in that it is attached to the partition plug (10). The method of claim 3, wherein The first end of the partition plug 10 adjacent to the feed passage segment 1 has a dome-shape depression 16 and the partition 11 is fixed to the dome-shaped depression 16. Characterized in that the device. The method of claim 5, The domed depression (16) is characterized in that it is perforated in the direction of the discharge passage (2a, 2b). The method of claim 3, wherein And the screw plug (14) is screwable within the bore (12) at the rear of the partition plug to secure the partition plug (10) in an axial position. The method of claim 4, wherein And the screw plug (14) is screwable within the bore (12) at the rear of the partition plug to secure the partition plug (10) in an axial position. A device for dispensing non-Newtonian liquid material flowing along passage 21, The liquid material has a viscosity that gradually decreases outward in cross section of the flow flowing through the substantially T-shaped passage branch T, which directs and distributes the liquid flow, The device is located in the passage branch (T) and has a central component (viscosity component) of the liquid substance supplied from the supply passage segment 21 before being flowed into the discharge passages 22a and 22b in two components. A distributor 32 for dispensing, The two components are flown in front of the discharge passages 22a and 22b, preferably flowing in the radial direction, respectively, And the viscous components of the liquid flowing into the outlet passages (22a, 22b) are substantially distinct and symmetrically distributed. The method of claim 9, The flow direction of the two components is substantially perpendicular to the longitudinal axis of the outlet passages (22a, 22b). The method of claim 9, The current transformer (23) is characterized in that it extends into one end of the feed passage and widens in a direction perpendicular to the blade (24) starting from the blade (24) and then narrowing again. The method of claim 10, The current transformer (23) is characterized in that it extends into one end of the feed passage and widens in a direction perpendicular to the blade (24) starting from the blade (24) and then narrowing again. The method of claim 11, The current transformer (23) is characterized in that it is located not in contact with the wall of the feed passage segment (21). The method of claim 11, The current transformer (23) is characterized in that it is fixed to the passage branch (T) by a web (27) located at the rear end in the flow direction. The method of claim 13, The current transformer (23) is characterized in that it is fixed to the passage branch (T) by a web (27) located at the rear end in the flow direction. The method of claim 9, The shape of the current transformer 23 begins with a cylinder comprising the blade 24 positioned at the front end, and then a retracted portion extending from two sides 25 lying substantially parallel to the blade. ) And then continued as cylindrical segment 31, The current transformer (23) is characterized in that it is insertable and fixable to the underside of the passage branch (T) via the cylindrical segment (31), rather than by the bore of the underside of the passage branch (T).

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