JPH025133B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of the Invention The present invention relates to a rotating screw used for extruding synthetic resins, rubber, injection molding machines, or kneading processed food products.

(b) Background of the Invention Conventionally, in order to improve the properties of resin raw materials, various organic and inorganic substances have been mixed and kneaded and used for molding.

The same is true in the food field, such as paste products, where various powders are mixed to increase nutritional value and improve taste.

Various types of screws having special kneading sections have been developed and put into practical use so that additives can be sufficiently stirred and kneaded into these raw materials.

However, in reality, when emphasis is placed on kneading, the discharge amount decreases, and when the discharge amount is increased, kneading cannot be performed sufficiently, which is a contradictory result.

In order to increase the kneading effect while not reducing the discharge rate, it is necessary to increase the size of the device or use a multi-shaft screw with a complicated structure and high cost.

(c) Purpose of the Invention This invention has an excellent stirring and kneading effect even with a single-screw, and exhibits a high degree of dispersion and kneading for resin raw materials, glass fibers, calcium carbonate, and any other additives. The purpose of the present invention is to provide a rotating screw that can be expected to produce a large discharge amount without causing a stagnation phenomenon.

(d) Structure of the Invention The rotating screw of the present invention continuously forms a generally parallelogram-shaped recess in the unfolded state with protrusions front and rear along the helical direction of the outer periphery of the screw, and the depth of each of these recesses is equal to the depth of the screw in the helical direction. The kneading part is formed so that it is deepest in the center and gradually becomes shallower as it reaches the front and rear protrusions, and each protrusion has a kneading part located in the center of an adjacent concave part and facing each other with the concave part in between. It is characterized by

(E) Effects of the Invention According to the present invention, in the kneading section, by eliminating screw flights and providing regular irregularities in the spiral direction over the entire outer peripheral surface, the resin raw material and the paste raw material and the additives added thereto can be mixed. While repeatedly and continuously applying a compression and expansion action in the radial direction and a compression and extension action in the axial direction to the additive, the side wall of the protrusion applies a feeding action in the transport direction.

Therefore, the additives are mixed while being reliably dispersed in the resin raw material and the kneaded product, and a sufficiently kneaded product is obtained at the end of the kneading section.

(f) Examples An embodiment of the present invention will be described in detail based on the drawings.

In the drawing, 1 is a cylindrical heating cylinder,
A rotating screw 2 is inserted inside and driven by power from a motor (not shown) or the like.

This rotary screw 2 has a kneading section 3 and a screw section 5 in which normal flights 4 are formed in the front and back or either side of the transfer direction.

The kneading section 3 is provided with protrusions 6, 6, .
Concave portions 8, 8 are continuously formed in the shape of a substantially parallelogram in the unfolded state, with the depth being deepest at the central portion 7 between the two portions 6 and gradually becoming shallower toward the protrusions on both sides.

Adjacent spirals are shifted in phase by 60 degrees, and each protrusion 6, 6 is located on the side of the deepest central part 7 of the adjacent recess 8, 8, and each protrusion 6, 6 is separated from the outer peripheral surface of the screw shaft. It is formed in a protruding state every 60 degrees.

Therefore, each of the recesses 8, 8 is arranged with a phase shift of 60 degrees from the adjacent recesses on both sides, and the bottom surfaces of both recesses 8, 8 are the same at 30 degrees before and after the protrusion 6. Concave communication path 9, 9 which becomes depth
... are formed, and a transfer surface is formed by the side wall 10 of the protrusion 6.

The kneading section 20 shown in FIG. 3 and FIG.
... are provided, and recesses 8, 8 are continuously formed such that the recesses 8, 8 are deepest at the central portion 7 between the protrusions 6, 6, and gradually become shallower toward the protrusions on both sides.

In this case, the adjacent spirals are shifted in phase by 90 degrees, and each protrusion 6, 6 is also located on the side of the central deepest part 7 of the adjacent recess 8, 8, and each protrusion 6, 6 protrude from the outer circumferential surface of the screw shaft at every 90 degrees, and recess communication passages 9, 9 are formed at 45-degree positions before and after each protrusion, and the bottom depths of both recesses 8, 8 are the same. side wall 1
0 forms the transport surface.

FIG. 5 shows a cross section of a kneading section 30 in which protrusions 6 are provided at every 90 degrees in the helical direction, and in this case, the recesses 8 are arranged 45 degrees out of phase with the adjacent recesses.

When additives are mixed into the resin raw material or the edible dough raw material using the rotary screw 2 configured in this way, the raw materials are sequentially transferred on the transfer surface of the side wall 10 of the protrusion 6 while being melted in the kneading section 3. .

During this transfer, compressive force is applied to the raw materials and additives by the continuous protrusion 6, the bottom surface of the smoothly curved concave part 8, and the inner surface of the heating cylinder 1, and the concave part 8 Under the dispersion action developed in the axial direction, some of the raw material flows into the adjacent recess 8 from the communication path 9 between the recesses, repeatedly causing a pulsating turbulent flow phenomenon.

As a result, the raw material kneaded with additives becomes a uniform raw material that has been thoroughly dispersed, stirred, and kneaded by the time it reaches the outlet of the kneading section, and is extruded by the screw section 5 that is continuously provided. .

In this invention, by eliminating the flight part of the normal screw and forming regular irregularities along the spiral on the entire outer peripheral surface, the dispersion stirring and kneading effect is improved while increasing the discharge amount compared to the conventional kneading device with flights. has improved significantly.

[Brief explanation of drawings]

Fig. 1 is a side view of the first embodiment of the present invention, Fig. 2 is a sectional view taken along line A-A in Fig. 1, Fig. 3 is a side view of the second embodiment, and Fig. 4 is B in Fig. 3. -B cross-sectional view and FIG. 5 are cross-sectional views of the third embodiment. DESCRIPTION OF SYMBOLS 1... Cylindrical heating cylinder, 2... Rotating screw, 3, 20, 30... Kneading section, 6... Protrusion part, 7... Center of recess, 8... Recess, 9... Recess communication path.

Claims (1)

[Scope of Claims] 1. A screw having a kneading part inserted into a cylindrical heating cylinder, the kneading part having a substantially parallel four-sided shape in an expanded state with a protruding part in the front and back along the spiral direction on the outer periphery thereof. The depth of each of these recesses is the deepest at the central part in the spiral direction and gradually becomes shallower as it reaches the front and rear protrusions, and each protrusion is formed in the central part of the adjacent recess. The rotary screws are positioned opposite each other with a concave portion in between.