JPH08281740A - Resin molding screw - Google Patents

Abstract

PURPOSE: To provide a resin molding screw in which the plasticizing capacity is improved while assuring the kneading capacity of resin. CONSTITUTION: A resin molding screw 10 comprises a kneading unit 11 used by mounting at a cylinder, a metering unit 12 at the end continued to the unit 11, and a main flight 1, subflights 2, 3, wherein the pitch of the flight 1 of the unit 11 is varied gradually smaller toward the end. The groove depth of the subflight 2 provided at the unit 11 is gradually deepened toward the end, and further the groove depth of the subflight 3 from the subflight 2 to the metering unit is gradually changed to shallow.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin molding screw used by being mounted on a cylinder.

[0002]

2. Description of the Related Art Conventionally, a dam provided between the main flights of a resin molding screw mounted on a cylinder of an injection molding machine or an extrusion molding machine is disclosed in, for example, JP-A-63- In Japanese Patent No. 122513, a resin molding screw having a subflight slightly lower than the main flight, and a starting end portion and an end portion of the subflight function as a weir parallel to the axial direction, and a resin molding screw connected to the main flight. Has been described.

Further, Japanese Patent Application Laid-Open No. 4-71818 discloses a screw for an injection molding machine in which two or more sub flight parts are provided in the compression part of a screw having a measuring part and a compression part. .

[0004]

However, the above-mentioned JP-A-63-122513 and JP-A-4-718.
In the resin molding screw or the injection molding machine screw described in Japanese Patent No. 18, the kneading property is improved by the shearing force applied to the resin when the resin gets over this subflight by providing the subflight. However, on the other hand, there arises a problem that the plasticizing ability is lowered due to the shear resistance applied to the resin, which eventually affects the productivity.

The present invention has been made by paying attention to the above-mentioned problems, and an object of the present invention is to solve these problems and secure the kneading ability of the resin.
It is intended to provide a resin molding screw capable of improving the plasticizing ability.

[0006]

The resin molding screw of the present invention has a kneading section mounted on a cylinder for use, and a measuring section at the tip following the kneading section, and has a main flight and a subflight. In the resin molding screw constituted by, the pitch of the main flight of the kneading section is gradually changed toward the tip, and the groove depth of the first subflight provided in the kneading section is directed toward the tip. It is characterized in that the groove depth of the second subflight from the first subflight to the measuring portion is gradually changed to be shallow.

That is, the subflight increases the shear resistance received by the resin to secure the kneading property, and the groove depth of the first subflight is gradually deepened toward the tip so that the cross-sectional area between flights is directed toward the tip. It is intended to improve the plasticizing ability, that is, the amount of plasticizing by making the temperature constant. Further, the heat conduction from the cylinder to the resin is reduced by making the groove deep. In order to improve the heat conduction, the pitch of the main flight is gradually reduced toward the tip to increase the heat conduction received by the resin and prevent the deterioration of the kneading property.

[0008]

In the resin molding screw of the present invention, the pitch of the main flight of the kneading section is gradually changed toward the tip, and the groove depth of the first subflight provided in the kneading section is small. Temporarily deeper toward the tip,
Further, since the groove depth of the second subflight from the first subflight to the measuring portion is provided with a shallow change, the plasticizing ability can be improved while ensuring the kneading ability of the resin.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side view showing an example of the resin molding screw of the present invention. In FIG. 1, 10 is a resin molding screw, and this resin molding screw 10 is mounted on a cylinder for use.

This resin molding screw 10 has a kneading section 11 and a measuring section 12 at the tip following the kneading section 11, and has a main flight 1, a first subflight 2, and a second subflight. 3 and 3.

Pitch P of main flight 1 of kneading section 11
₁ is provided with a small change toward the tip to the provisional pitch P ₂ .

Further, the groove depth D ₂ of the first subflight 1 provided in the kneading section 11 is a temporary groove depth D ₃ toward the tip.
The groove depth D ₃ of the second subflight 3 extending from the first subflight 1 to the weighing section 12 changes to a temporary groove depth D ₄ with a shallow depth. It is provided.

FIG. 2 is a development view of the resin molding screw shown in FIG. 1, showing a relative relationship between the main flight 1, the first subflight 2, and the second subflight 3.

Specific examples of flight and groove depth of the resin molding screw 10 are shown below. For example, the pitch P ₁ of the main flight 1 of the kneading section 11 is 95 mm,
The provisional pitch P ₂ is provided with a small change to 95 mm toward the tip.

Further, the groove depth D ₂ of the first subflight 1 of the kneading section 11 is 2.5 mm, and the groove depth D _{3 is} temporary toward the tip.
Is deepened to 10 mm. Further, the groove depth D _{3 of} 10 mm from the first subflight 1 to the measuring portion 12 is shallowly changed to 6 mm which is the temporary groove depth D ₄ .

As described above, the first subflight 2,
The second subflight 3 increases the shear resistance of the resin to ensure kneading properties, and the groove depth of the first subflight 2 is gradually increased toward the tip, and the main flight 1 The plasticizing ability, that is, the plasticizing amount can be improved by making the inter-sectional area constant toward the tip.

[0017]

In the resin molding screw of the present invention, the pitch of the main flight of the kneading section is gradually changed toward the tip, and the groove depth of the first subflight is provided in the kneading section. Is provided deeper toward the tip, and the groove depth of the second subflight from the first subflight to the measuring section is gradually changed to be shallower. It is possible to improve the plasticizing ability while securing it. Therefore, it is suitably used as a resin molding screw.

[Brief description of drawings]

FIG. 1 is a side view showing an example of a resin molding screw of the present invention.

FIG. 2 is a development view of the resin molding screw shown in FIG.

[Explanation of symbols]

 1 Main Flight 2 First Subflight 3 Second Subflight 3a Recess 10 Resin Molding Screw 11 Kneading Section 12 Measuring Section D Groove Depth P Pitch

Claims (1)

[Claims] 1. A resin molding screw having a kneading section mounted on a cylinder for use, and a measuring section at the tip following the kneading section, and comprising a main flight and a subflight. The pitch of the flight is provided so as to change slightly toward the tip, and the groove depth of the first subflight provided in the kneading section is provided deeper toward the tip, and further, the first subflight is provided. A resin molding screw, wherein the groove depth of the second sub-flight reaching the measuring portion is changed to be shallow.