JP2000071252A - Screwed extruder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a screwed extruder which is small in size and can improve productivity and reduce the rotational driving force of a screw. SOLUTION: In a screwed extruder 11 in which a screw 13 is set in a barrel part 12, and a resin 7 supplied from an inlet formed at one end of the barrel part 12, while being melted by the rotation of the screw 13, is extruded from an outlet nozzle part 16 at the other end, the ratio L/D of the length L of the screw 13 to the diameter D of the screw 13 is arranged to be about 1-3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw extruder for supplying a molten resin in a blow molding machine, an injection machine or the like.

[0002]

2. Description of the Related Art FIG. 2 is a cut-away side view showing an example of a conventional screw extruder. A conventional screw extruder 1 has a slender tubular body 2 (barrel) inside which a motor or the like is driven. It has a configuration in which a screw 4 rotationally driven by the device 3 is concentrically inserted and arranged. A spiral ridge 5 that slides along the inner surface of the body 2 is provided on the outer peripheral surface of the screw 4.

An input port 8 for supplying a resin material 7 from a hopper 6 is formed at an end of the body section 2 on the drive device 3 side. An outlet nozzle portion 9 is formed at the opposite end.

Further, a plurality of temperature control devices 10 are provided on the outer peripheral surface of the body 2 in the axial direction. The screw extruder 1 needs to stir and stir the resin in a stable manner with the screw 4 and supply the resin adjusted to a molten state with a uniform and optimum softness. A plurality of temperature controllers 10 are provided to perform temperature control with an appropriate temperature gradient in the axial direction.

In the screw extruder 1, while the screw 4 is driven to rotate by the driving device 3, the resin material 7 in the form of pellets is transferred from the hopper 6 to the body 2 while the temperature in the axial direction is controlled by each temperature control device 10. Supply within. Then, the supplied resin material 7 is sequentially conveyed to the left side in FIG. 2 while being melted and stirred by the screw 4, and the resin in a good molten state is extruded from the outlet nozzle portion 9.

In the screw extruder 1 as shown in FIG. 2 which has been recently implemented, the screw 4 is rotated at a high speed in order to increase the productivity of the screw extruder 1. , The residence time of the resin in the screw extruder 1 becomes shorter,
Poor plasticization of the resin occurs.

In order to address the problem of poor plasticization,
Conventionally, the length of the screw 4 has been further increased. Generally, the screw 4 has a ratio L / L of the length L to the diameter D.
D was very long, about 20-35.

[0008]

However, in the conventional screw extruder, as described above, the screw 4 is
Since the ratio L / D between the length L and the diameter D is as long as about 20 to 35, the entire device becomes very long,
It is difficult and expensive to manufacture, and has a problem in installation space.

Further, as described above, when the long screw 4 is rotated at a high speed in order to improve the productivity, the pressure in the screw extruder 1 increases, and there is a problem that the screw 4 is galled and worn. Further, the screw 4 may be broken.

An object of the present invention is to solve such a conventional problem, and it is an object of the present invention to provide a screw extruder which is small in size, can increase productivity, and can extrude at low pressure.

[0011]

SUMMARY OF THE INVENTION According to the present invention, a screw is incorporated in a body portion, and while a resin material supplied from an inlet provided at one end of the body portion is melted by rotation of the screw, an outlet nozzle portion at the other end is provided. A screw extruder that extrudes from the screw, wherein the ratio L / D of the length L and the diameter D of the screw is L / D.
Is set to about 1 to 3 in the screw extruder.

According to the present invention, the screw is adjusted so that the ratio L / D of the length L to the diameter D is in the range of about 1-3.
By having a thick and short configuration, the screw extruder has a very compact configuration.

Further, when the conventional screw groove shape is directly increased in diameter in order to obtain the same production volume as the conventional one, the internal pressure can be reduced.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a cut-away side view showing an embodiment of the present invention. 1 in FIG. 1 is a screw extruder,
In the screw extruder 11, a screw 13 is inserted and disposed in a cylindrical body 12, and a ratio L / D of the length L to the diameter D of the screw 13 is in a range of about 1 to 3. It is a thick and short shape that becomes

The screw 13 is rotatably driven by a driving device 14 such as a motor. A screw formed on the outer peripheral surface of the screw 13 so as to slide along the inner surface of the body 12. A ridge 15 is provided.
Further, an input port 8 for supplying the resin material 7 from the hopper 6 is provided at an end of the body section 12 on the drive device 14 side.
Are formed. An outlet nozzle 16 is formed at the end of the body 12 opposite to the input port 8, and a plurality of temperature control devices 17 are provided on the outer periphery of the body 12. The screw extruder 1 is controlled by the adjusting device 17.
Temperature control with a temperature gradient in the axial direction can be performed.

Next, the operation of the above embodiment will be described.

In the screw extruder 11 shown in FIG. 1, the screw 13 is driven to rotate by the driving device 14 and the temperature of the axial direction is controlled by the temperature control devices 17 to control the pellet-shaped resin material 7 from the hopper 6.
Is supplied into the body 12, the supplied resin material 7 becomes
While being melted and agitated by the screw 13, the resin is sequentially conveyed to the left side in FIG.

At this time, the length L and the diameter D of the screw 13 are
Of the screw 13 which is thicker and shorter than the conventional screw 4 (FIG. 2) so that the ratio L / D of the screw
Can have a very compact configuration.

The length of the spiral ridge 5 of the conventional screw 4 in FIG. 2 is the same as the length of the spiral ridge 15 of the screw 13 in FIG. 1, and the moving peripheral speeds of the spiral ridges 5 and 15 are the same. It was found that when the residence time of the resin in the body parts 2 and 12 was the same, the internal pressure of the body part 12 could be reduced. Therefore, it is also advantageous from a mechanical design point of view.

The ratio L of the length L to the diameter D of the screw 13
When / D is 1 or less, there is a problem that the temperature controllability is significantly reduced. In the screw extruder 11, a plurality of temperature control devices 17 are provided in the axial direction in order to stably supply the resin in a uniform molten state by performing stable melting and stirring of the resin.
It is necessary to perform temperature control so as to provide an appropriate temperature gradient with
The ratio L / D needs to have a length of about 1, so the value of L / D is set to a range of at least one.

The ratio L of the length L to the diameter D of the screw 13
/ D is set to a maximum of 3 because the ratio L / D is 3
In the case described above, the above-described screw extruder cannot be significantly reduced in size and the effect of reducing the pressure cannot be meaningfully exhibited. For this reason, the ratio L / D is set to a range of 3 at the maximum.

It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that various changes can be made without departing from the spirit of the present invention.

[0024]

According to the present invention, the screw is made thick and short so that the ratio L / D of the length L to the diameter D is in the range of about 1 to 3, thereby reducing the screw. An excellent effect that the extruder can have a very compact configuration can be obtained.

Further, when the diameter of the screw is increased, the effect that the internal pressure of the body can be reduced can be obtained.

[Brief description of the drawings]

FIG. 1 is a cut-away side view showing an example of an embodiment of the present invention.

FIG. 2 is a cut side view showing an example of a conventional screw extruder.

[Explanation of symbols]

 7 Resin material 8 Input port 11 Screw extruder 12 Body part 13 Screw 16 Outlet nozzle part D Diameter L Length

 ──────────────────────────────────────────────────の Continuing from the front page (72) Inventor Yoshiharu Shitara 1st place, Shin-Nakahara-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture Inside the Technical Research Institute, Ishikawajima-Harima Heavy Industries Co., Ltd. (72) Inventor Hiroyuki Otsuka Shin-Nakahara-cho, Isogo-ku, Yokohama-shi, Kanagawa No. 1 Ishi Kawashima Harima Heavy Industries, Ltd. Technical Research Institute (72) Inventor Atsushi Hirata No. 1 Shin-Nakahara-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture BK13 BK40 4F206 JA03 JA06 JD01 JF01 JF12 JF13 JQ11 4F207 KA01 KF01 KF12 KF13 KK12 KL01

Claims (1)

[Claims] 1. A screw extruder in which a screw is incorporated in a body, and a resin material supplied from an input port provided at one end of the body is melted by rotation of the screw and pushed out from an outlet nozzle at the other end. A screw extruder, wherein the ratio L / D of the length L and the diameter D of the screw is about 1 to 3.