JPH0459327A - High kneading screw - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a high kneading screw that can be applied to injection molding machines and extrusion molding machines.

[Prior Art] A conventional high-kneading screw is shown in FIGS. 4 and 5. FIG. 4 is a partially cutaway vertical sectional view of the high-kneading screw, and FIG. 5 is a developed view of the screw in FIG. 4.

In FIG. 4, the screw 1 is connected to the supply section FZ and the compression section C2.
, a metering section MZ, a supply section FZ and a compression section C.
The first sub-flight β1 branches from the main flight α at the boundary of Z and merges with the opposing main flight α again at the boundary between the compression part CZ and the measurement part MZ, and the boundary between the compression part C2 and the measurement part MZ. A second sub-flight β2 branches off from the main flight α of the section and merges with the main flight α again in the direction of the screw tip.
The structure has the following.

The first sub-flight β1 and the second sub-flight β2 are divided into a resin material supply thread groove 2, a semi-molten plasticized resin thread groove 3, and a molten plasticized resin discharge side thread groove 4, respectively.

Further, the gap between the cylinder barrel 5 and the first sub-flight β in the compression section CZ is always constant from the supply section FZ side to the metering section MZ side, and furthermore, similarly in the metering section MZ, the gap between the cylinder barrel 5 and the first sub flight β is constant. The gap between the cylinder barrel 5 and the second sub-flight β2 is also constant, and the gap between the cylinder barrel 5 and the first sub-flight β is larger than the gap between the cylinder barrel 5 and the second sub-flight β2. It is configured.

Now, in FIG. 4, the resin supplied from the hopper 6 to the supply section FZ receives thermal energy from a heater (not shown) and shear energy due to the rotation of the screw 1, and is gradually melted and transferred forward.

In addition, in the compression section C2, the solid resin is dammed up by the first sub-flight β1, and as the screw 1 rotates, a molten film is formed between the cylinder barrel 5 and the solid resin due to its strong shearing action, and the molten film is sheared. The force rapidly accelerates the melting of the surface of the solid resin. In this way, the molten resin passes over the first sub-flight β1 and is transferred to the semi-molten plasticized resin thread groove 3. Although the molten resin is further transferred from the semi-molten plasticized resin thread groove 3 to the second auxiliary flight β to the molten plasticized resin discharge side thread groove 4, the gap between the cylinder barrel 5 and the first auxiliary flight β1 Regarding the gap between the second sub-flight 62 and the former cylinder barrel 5, the gap between the first sub-flight β1 is larger than the latter, and the molten resin that crosses the second sub-flight β2 is further It is subjected to strong shearing forces and is completely melted.

[Problems to be Solved by the Invention] As described above, in the conventional high-kneading screw, the first sub-flight is arranged as a weir between the main flights in the compression section,
Furthermore, since the second sub-flight is arranged as a weir between the main flights in the metering section MZ, crosstalk is low. There was a drawback that reducing the gap between the two would reduce the throughput.

[Means for Solving the Problem] In order to solve such problems, in the present invention, in a partial range of the screw, the resin material supply side thread groove, the semi-molten plasticized resin side thread groove, and the molten plasticized resin In a multi-flight high-kneading screw having a sub-flight separating the discharge side thread groove, the depth of the resin material supply side thread groove is continuously gradually decreased from a deep groove part to a shallow groove part in the resin injection direction. None, the depths of the semi-molten plasticized resin side thread groove and the molten plasticized resin discharge side thread groove are unchanged with respect to the resin injection direction, and at the starting point of multiple flight formation in the resin injection direction, the resin The depth of the thread groove on the material supply side is made deeper than the thread groove depth on the semi-molten plasticized resin side and the thread groove on the molten plasticized resin discharge side, and the depths of the thread grooves are kept at a constant ratio until the end point of multiple flight formation. The configuration is such that the number decreases.

[Function] In the compression part, sub-flights that form a weir are arranged in the resin material supply side thread groove, the semi-molten plasticized resin side thread groove, and the molten plasticized resin discharge side thread groove, and , the depth of the resin material supply thread groove is continuously gradually decreased;
The depth of the thread groove on the semi-molten plasticized resin side and the thread groove on the molten plasticized resin discharge side are kept unchanged, and the groove depths of both are made almost the same, and the depth of the resin material supply thread groove is set as the depth of the thread groove on the semi-molten plasticized resin side. Because the depth of the resin thread groove and the molten plasticized resin discharge side thread groove are made deeper, the extrusion amount is regulated because a certain amount of resin sent from the supply side is not blocked between multiple flights and the extrusion force is stabilized. This makes it easy to change colors and significantly improves crosstalk.

[Example] Figures 1 to 3 show one example of a high kneading screw according to the present invention.
Examples are shown in which Fig. 1 is a partially cutaway vertical sectional view of a high-kneading screw, Fig. 2 is a developed view of the screw, and Fig. 3 is a cross-sectional view of the high kneading screw.
The flow state of the resin in each cross section at point D is shown.

In Fig. 1, the screw l is connected to the supply section FZ and the compression section CZ.
, and a measuring section MZ. In addition, a first sub-flight β and a second sub-flight β2 are arranged in the compression section CZ, and the first sub-flight β1 and second sub-flight β2 connect the resin material supply screw groove 2 and the semi-molten plasticization. It is divided into a resin thread groove 3 and a melt plastic discharge side thread groove 4.

In addition, the main flight α at the boundary between the supply section FZ and the compression section CZ
The first sub-flight β1 branches off from the boundary between the compression part CZ and the measurement part MZ and merges with the opposing main flight α, and the main flight α of the compression part C7, which is threatened by road sludge and near-dirt, branches off. Then, at the boundary between the compression part CZ and the metering part MZ, the second sub-flight β2 joins the opposing main flight α again, and enters 1/.

As shown in FIG. 3, if the gap between the cylinder barrel 5 and the first sub flight β1 in the compression part CZ is 21, and the gap between the cylinder barrel 5 and the second sub flight β2 is 22, then the cylinder barrel 5 and the gap between the cylinder barrel 5 and the first sub flight β1 are 22. Gap with first secondary flight β1 2. is constantly constant from the supply section FZ side to the metering section MZ side, and furthermore, the gap Z between the cylinder barrel 5 and the second sub-flight β2 is also constant, and Z r > 2
It is configured to be 2.

Furthermore, regarding the depth number of the thread groove in the compression part CZ, first of all, in the resin material supply side thread groove 2, there is a continuous heat Hl>H2>H2>H from the deep groove part to the shallow groove part in the resin injection direction.
It has a configuration that gradually decreases so that .

In addition, the semi-molten plasticized resin thread groove 3 and the molten plasticized resin discharge side thread groove 4 in the compression part C7 remain unchanged in the resin injection direction, and have the same groove depth, that is, 1
(B=Ha. The depth of both grooves 3.4 near the starting point of compression part CZ formation is shallower than the depth of the resin material supply side screw groove 2 described above, The depth of both grooves 3 and 4 near the completion point is configured to be approximately the same as the depth of the resin material supply side screw groove 2 described above.

The operation of the high kneading screw configured as above will be explained.

In FIG. 1, the resin supplied from the hopper 6 to the supply section FZ receives thermal energy from a heater (not shown) and shear energy due to the rotation of the screw 1, and is gradually melted and transferred forward.

In the compression section CZ, the solid resin that has moved from the supply section FZ is stopped by the first sub-flight β1, and as the screw 1 rotates, a molten film is formed between the cylinder 5 and the solid resin due to its strong shearing action. The melting of the surface of the solid resin is rapidly promoted by the shear force of the molten film.

Furthermore, when the molten resin that has moved over the 11th WII flight β1 crosses over the second sub-flight β2, the molten resin crosses the gap Z between the cylinder barrel 5 and the second sub-flight β2.
2 is the cylinder barrel 5 and the first sub-flight β1 described above.
Since the gap zI is smaller than the gap between the two, and the semi-molten plasticized resin thread groove 3 and the molten plasticized resin discharge side thread groove 4 are shallow, the resin receives even more shear energy from the rotation of the screw 1, and the resin is completely melted. This improves crosstalk. In particular, in the present invention, the resin group staying in the resin material supply thread groove 2 in the compression part CZ, the semi-molten plasticized resin thread groove 3 and the molten plasticized discharge side thread groove 4 is formed in the axial direction of the screw 1. The resin moves smoothly from the supplying part FZ side to the measuring part MZ side, and a certain amount of resin sent from the supplying group FZ side is blocked by this triple flight part and the extrusion force is stabilized. Metering takes place constantly.

In addition, in the embodiment of the present invention, the gap ZI between the cylinder barrel 5 and the first sub-flight β in the compression part C2 is
Although the case has been described in which the gap is larger than the gap Z2 between the cylinder barrel 5 and the second sub-flight 62, the gap is not limited to this, and almost the same effect can be obtained even if Z=72.

Furthermore, as described above, the case where the depth H5 of the semi-molten plasticized resin thread groove 3 and the depth H6 of the molten plasticized resin discharge side thread groove 4 are the same (H5=H,), but H, >H
Almost the same effect can be obtained by setting s or H6<H.

In addition, in the embodiment of the present invention, the second flight α is provided between the main flights α. A first subsidiary flight of the second thread that branches the third thread and separates it into a resin material supply thread groove and a semi-molten plasticized resin thread groove, and the semi-molten plasticized resin thread groove and the molten plasticized resin discharge. Although we have described a high-kneading screw having a triple flight consisting of a second sub-flight of a third thread that separates into a side thread groove, the invention is not limited to this, and the screw thread may be further branched into a fourth or more thread. It is also possible to have multiple flights.

[Effects of the Invention] As is clear from the above explanation, in the present invention, the compression part of the screw has a thread groove on the resin material supply side, a thread groove on the half-molten plasticized resin side, and a thread groove on the molten plasticized resin discharge side. In a multi-flight high kneading screw provided with a sub-flight for separation, the depth of the resin material supply side thread groove is gradually decreased from a deep groove part to a shallow groove part in the resin injection direction, so that the semi-molten The depths of the plasticized resin side thread groove and the molten plasticized resin discharge side thread groove are kept unchanged with respect to the resin injection direction, and at the starting point of multiple flight formation in the resin injection direction, the resin material supply side thread groove is By making the depth deeper than the depth of the semi-molten plasticized resin side thread groove and the molten plasticized resin discharge side thread groove, and making the depth of the thread groove decrease at a constant rate until the end point of multiple flight formation. , when a certain amount of molten resin sent from the supply side passes over each flight, the flow velocity and pressure increase, which significantly improves crosstalk, and the extrusion force is stabilized because the resin is not blocked between each flight. The amount of extrusion is not restricted and color changes are easy.

[Brief explanation of the drawings] Figures 1 to 3 show a high kneading screw according to the present invention.
Examples are shown in which Fig. 1 is a partially cutaway vertical sectional view of a high-kneading screw, Fig. 2 is a developed view of the screw, and Fig. 3 is a cross-sectional view of the high kneading screw.
The flow state of the resin in each cross section at point D is shown. 4 and 5 show a conventional high-kneading screw, FIG. 4 is a partially cutaway vertical sectional view of the high-kneading screw, and FIG. 5 is a developed view of the screw in FIG. 4. l...Screw, 2...Resin material supply thread groove, 3...Semi-molten plasticized resin thread groove, 4.
...Melted plasticized resin discharge side thread groove, 5...
・Cylinder barrel, 6...Hopper, α...Main flight, β,...1st sub-flight, β2...2nd sub-flight, MZ...Measuring section, CZ ... Compression section, FZ... Supply section.

Claims (1)

[Claims] In a multi-flight high-kneading screw that is provided with a sub-flight that separates a resin material supply side thread groove, a semi-molten plasticized resin side thread groove, and a molten plasticized resin discharge side thread groove in a partial range of the screw, the resin material supply The depth of the side thread groove is gradually decreased from the deep groove part to the shallow groove part in the resin injection direction, and the depth of the semi-molten plasticized resin side thread groove and the molten plasticized resin discharge side thread groove is The depth of the thread groove on the resin material supply side is kept unchanged with respect to the resin injection direction, and at the first multiple flight formation start point in the resin injection direction, the depth of the thread groove on the semi-molten plasticized resin side and the melted plasticized resin side thread groove are A high-kneading screw characterized in that the depth of the thread grooves on the resin discharge side is deeper than the depth of the thread grooves on the resin discharge side, and the depths of the thread grooves decrease at a constant rate until the end point of multiple flight formation.