JP-2026076012-A - Injection molding machine

Abstract

[Problem] To provide an injection molding device capable of supplying molding material from multiple hoppers in appropriate proportions. [Solution] An injection molding device for injecting molding material into the cavity of a clamped mold comprises a heating cylinder filled with molding material, a first hopper for supplying molding material to the heating cylinder, a second hopper for supplying molding material to the tip side of the heating cylinder from the first hopper, and a screw having a helical groove formed on its outer circumference, which rotates and retracts inside the heating cylinder to measure the molding material, and advances inside the heating cylinder to inject the molding material into the cavity. The screw has a first portion facing the first hopper and a second portion facing the second hopper, the volume per unit length of the helical groove being larger than that of the first portion. [Selection Diagram] Figure 3

Inventors

• 澤田 靖丈
• 井上 玲
• 下楠薗 壮
• 松尾 明憲

Assignees

• ＴＯＹＯイノベックス株式会社

Dates

Publication Date

20260511

Application Date

20241023

Claims (6)

1. In an injection molding device that injects molding material into the cavity of a clamped mold, A heating cylinder filled with molding material, A first hopper that supplies molding material to the heating cylinder, A second hopper supplies molding material from the first hopper to the tip side of the heating cylinder, A screw has a helical groove formed on its outer surface and rotates and retracts inside the heating cylinder to measure the molding material, and moves forward inside the heating cylinder to inject the molding material into the cavity. The aforementioned screw is The first part facing the first hopper, An injection device characterized by having a second portion facing the second hopper, wherein the volume per unit length of the helical groove is larger than that of the first portion.
2. In the injection apparatus according to claim 1, The aforementioned screw is A shaft portion extending in a straight line, The shaft portion has a projection that extends radially outward from its outer circumferential surface and is spirally extended, The second part is characterized in that, compared to the first part, the depth of the helical groove is greater, the pitch of the protrusions is wider, or the width of the protrusions is narrower.
3. In the injection apparatus according to claim 1, The boundary between the first part and the second part is, When the screw is at its retraction limit, it is located in front of the first hopper, An injection device characterized in that it is located behind the second hopper when the screw is in its forward position.
4. In the injection apparatus according to claim 1, The injection device is characterized in that the first hopper and the second hopper have different areas of lower end openings for supplying molding material to the heating cylinder.
5. In the injection apparatus according to claim 1, The injection molding apparatus is characterized in that the first hopper and the second hopper have different supply positions for the molding material to the heating cylinder when viewed from the direction of extension of the heating cylinder.
6. A mold clamping device that opens and closes the mold and clamps it, A molding machine characterized by comprising the injection device described in claim 1.

Description

This invention relates to an injection molding device and molding machine capable of mixing and injecting multiple types of molding materials. Conventionally, injection molding devices for injecting molding material into the cavity of a clamped mold comprise a heating cylinder filled with molding material, a hopper that supplies molding material to the heating cylinder, and a screw that rotates and retracts inside the heating cylinder to measure the molding material, and then advances inside the heating cylinder to inject the molding material into the cavity. Furthermore, injection molding devices are known that have hoppers installed at multiple positions spaced apart in the extension direction of the heating cylinder in order to mix and inject multiple types of molding materials within the heating cylinder (see, for example, Patent Documents 1 to 3). Japanese Utility Model Publication No. 63-033917Japanese Unexamined Patent Publication No. 57-064534International Publication No. 2024/176361 This is a side view of the injection molding machine according to this embodiment.This is an exploded view of the heating cylinder, screw, first hopper, and second hopper.This diagram shows the relative positions of the heating cylinder, screw, first hopper, and second hopper.This diagram shows variations of hoppers.This figure shows the shape of a screw in a modified form. The injection molding machine 10 according to the present invention will be described below with reference to the drawings. The injection molding machine 10 is a device that injects a measured amount of plasticizer resin (molding material) into a mold to form a molded product. However, the specific example of the molding machine is not limited to the injection molding machine 10; a die-casting machine that injects molten metal (molding material) into a mold to form a molded product may also be used. [Configuration of injection molding machine 10] Figure 1 is a side view of the injection molding machine 10 according to this embodiment. As shown in Figure 1, the injection molding machine 10 mainly comprises a mold clamping device 20 and an injection device 30. The mold clamping device 20 opens and closes the mold 21 and clamps it. Specifically, the mold clamping device 20 mainly comprises a fixed die plate 23 that supports the fixed mold 22 and a movable die plate 25 that supports the movable mold 24. The fixed mold 22 and the movable mold 24 are supported so as to face each other in the left-right direction (horizontal direction) of the injection molding machine 10. The movable die plate 25 moves left and right along the tie bar 27 as the driving force of the mold opening/closing motor (not shown) is transmitted through the toggle link mechanism 26. When the movable die plate 25 moves to the left, the fixed mold 22 and the movable mold 24 separate. Conversely, when the movable die plate 25 moves to the right, the fixed mold 22 and the movable mold 24 come into contact, forming a cavity (internal space) inside the mold 21. Furthermore, when pressure is applied in the direction that moves the movable die plate 25 to the right, the fixed mold 22 and the movable mold 24 are clamped together. The injection molding device 30 plasticizes, measures, and injects the molding material. In this embodiment, the injection molding device 30 is positioned horizontally opposite the mold clamping device 20 (to the right of the mold clamping device 20). The injection molding device 30 mainly comprises a heating cylinder 31, a screw 32, a first hopper 33, and a second hopper 34. The heating cylinder 31 is a cylindrical component that extends linearly in the left-right direction from the injection molding machine 10. The heating cylinder 31 mainly comprises a resin passage 35 and a nozzle 36. A band heater (not shown) is attached to the outer circumferential surface of the heating cylinder 31 to heat it. The resin passage 35 is a cylindrical space extending axially (longitudinally) inside the heating cylinder 31. The resin passage 35 communicates with the outside of the heating cylinder 31 (the cavity of the mold 21) through a nozzle 36 located at the tip (front end) of the heating cylinder 31. In other words, the resin passage 35 is a space extending axially from the nozzle 36. The screw 32 is generally cylindrical in shape. A spiral groove (hereinafter referred to as "spiral groove 43") is formed on the outer surface of the screw 32, extending along its longitudinal direction. The screw 32 is housed within the internal space of the heating cylinder 31, allowing for movement (hereinafter referred to as "advance and retreat") and rotation within the injection molding machine 10. Furthermore, the screw 32 within the heating cylinder 31 is configured to be replaceable. In other words, screws 32 with different specifications (e.g., material, shape of the spiral groove 43, volume of the spiral groove 43) can be inserted into the heating cylinder 31. The screw 32 moves forward