JP3494782B2 - Screw removal method and device for injection molding machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw removing method for an injection molding machine and an apparatus therefor, and more particularly to a screw removing method for an injection molding machine for injecting a light alloy material and an apparatus therefor. .

[0002]

2. Description of the Related Art In a conventional in-line screw type injection molding machine, when a solid light alloy material is fed into a cylinder barrel from a hopper, the light alloy material is added by frictional heat generated by the rotation of the screw or a heater. It is melted by the heat generated and sent to the front of the cylinder barrel for weighing. The measured light alloy material in a molten state is injected into the mold by driving the screw by an axial method. The mold can be opened after waiting for cooling and solidification to obtain a molded product.

In the injection molding machine for injecting the above-mentioned light alloy material, when the screw is taken out from the cylinder barrel for the purpose of parts replacement of the backflow prevention device or material change, the temperature of the cylinder barrel is set to the temperature of the light alloy material. The temperature is raised to near the melting point, the cylinder head attached to the tip of the cylinder barrel is removed, and the screw is pushed out to the front of the cylinder barrel using an injection mechanism that gives the screw forward and backward movement and a screw drawing jig. I was taking it out.

[0004]

The following problems occur when the screw is taken out of the cylinder barrel after injecting a highly active light alloy material such as magnesium alloy or aluminum alloy with the above-mentioned injection molding machine. Points may occur. (a) Light alloy material in a molten state attached to the screw, screw head, backflow prevention ring of the backflow prevention device, etc. reacts with oxygen in the air and ignites and burns, causing the temperature of these parts to rise abnormally. , It may significantly reduce the mechanical properties. (b) It is dangerous that the molten light alloy material attached to the screw drips on the floor or the machine and catches fire or burns.
The working environment is bad. (c) Since the high-temperature screw is pushed out in a bare state, the operator who operates the operation panel in the vicinity is dangerous. (d) Since the extracted screw is very hot,
Suspending equipment such as wire rope for transportation is damaged immediately and cannot be used.

The present invention has been made to solve the above problems, and in an injection molding machine for injecting a light alloy material, when a screw is taken out, a light molten state attached to the screw is attached. It is an object of the present invention to provide a screw taking-out method and a device for taking out a screw that can be safely taken out by preventing ignition and burning of alloy material.

[0006]

A method for taking out a screw of an injection molding machine for injecting a solid light alloy material according to the present invention is a cylindrical metal attached to the tip of a cylinder barrel and having an inert gas atmosphere inside. The feature is that the screw is taken out while being inserted into the container.

A screw take-out device of an injection molding machine for injecting a solid light alloy material according to the present invention comprises a cylindrical metal container attached to the tip of a cylinder barrel, and an inert gas for supplying an inert gas into the container. And a gas supply member.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will now be described based on examples with reference to the drawings.

First, the injection molding apparatus will be described with reference to FIGS. 2 and 3. 2 and 3, the reference numeral 1 is a cylinder barrel, and the screw 2 is inserted therein. The cylinder barrel 1
The nozzle 4 is connected to the tip end of the cylinder via the cylinder head 3, and the hopper 13, which is a material supply unit, is connected to the rear end of the cylinder barrel 1. A heater 14 is attached to the outer peripheral walls of the cylinder barrel 1, the cylinder head 3 and the nozzle 4. The screw 2, the cylinder barrel 1 and the like described above form an injection unit.

An injection cylinder 15 is connected to the rear of the cylinder barrel 1, and an injection piston 16 is slidably fitted inside the injection cylinder 15. With the injection cylinder 15 and the injection piston 16, the rear pressure chamber 2
1a and the front pressure chamber 21b are partitioned, and an injection mechanism 23 that drives the screw 2 to move back and forth is configured. An output shaft 17 that is rotatable with respect to the injection piston 16 and is immovable in the central axis direction is supported inside the injection piston 16 with a radial bearing 18a and a thrust bearing 18b interposed therebetween. The screw 2 is mechanically coupled to the front end of the output shaft 17 by a coupling 19, and the rotating mechanism 22 including a hydraulic motor is connected to the rear end of the output shaft 17. The injection unit including the cylinder barrel 1, the screw 2, the injection mechanism 23, the rotation mechanism 22 and the like described above is attached to the mold clamping device by a moving cylinder device (not shown).
It is possible to move forward and backward.

Next, the operation of the above injection molding apparatus will be described.

The screw 2 is rotationally driven by the rotating mechanism 22 via the output shaft 17, and the light alloy material supplied from the hopper 13 is heated by the heater 14 provided in the cylinder barrel 1 and the like, while the screw 2 is being heated. Melt kneading is performed by. Here, the light alloy material is, for example, a magnesium alloy, an aluminum alloy, or the like,
These are crushed into chips of a predetermined size.

Then, by supplying pressure fluid from a pressure fluid supply source (not shown) to the rear pressure chamber 21a, the injection piston 16, the output shaft 17 and the screw 2 are integrally advanced, and a light alloy in a molten state is produced. The material can be injected into the mold 20 by the screw 2, and the pressure in the rear pressure chamber 21a can be maintained while the front pressure chamber 21b is drained. The injection piston 16, the output shaft 17, and the screw 2 can be integrally retracted by supplying the pressure fluid from the pressure fluid supply source to the front pressure chamber 21b.

Next, the screw take-out device will be described with reference to FIG.

The screw take-out device comprises the cylinder head 3 attached to the tip of the cylinder barrel 1.
After removing the nozzle 4 and the cylinder 4, a cylindrical metal container 5 attached to the tapered portion of the cylinder barrel 1, and a pipe which is an inert gas supply member for supplying an inert gas from the inert gas source 6 into the container 5. 7 and the like, and the pipe 7 is provided with a pressure regulator 8, a flow rate regulating valve 9 and the like. The cylindrical metal container 5 is attached to the tip of the cylinder barrel 1 with a screw or the like via a flange or the like provided at the end thereof, and can be hung by a crane or the like.

Next, the screw taking-out operation will be described.

First, the temperature of the cylinder barrel 1 is raised to the molding temperature range of the light alloy material by the heater 14 attached to the outer peripheral wall of the cylinder barrel 1, and the light alloy material remaining in the cylinder barrel 1 is heated. Is discharged to the outside as much as possible by a purging operation or the like.

Next, the screw 2 is forcibly retracted a little, and the coupling 19 for mechanically connecting the screw 2 and the output shaft 17 and the cylinder head 3 attached to the tip of the cylinder barrel 1 are provided. Remove the nozzle 4. Then, the output shaft 17 is further retracted, the output shaft 17 and the screw 2 are separated, the screw extraction jig 10 is inserted between them, the output shaft 17 is advanced, and the screw 2 is moved by the length of the screw extraction jig 10. The cylinder barrel 1
To the front of. Then, only the output shaft 17 is retracted again, a new screw drawing jig 10 is inserted between the output shaft 17 and the screw drawing jig 10, and the output shaft 17 is moved forward. While repeating the operation, the screw 2 is completely taken out from the cylinder barrel 1.

At this time, as shown in FIG. 1, a cylindrical metal container 5 hung by a crane or the like is arranged in the tapered portion of the cylinder barrel 2, and the screw 2 is replaced by the cylindrical metal container 5.
Be pushed out to the inside of. Moreover, the inert gas from the inert gas supply source 6 is supplied into the cylindrical metal container 5. The screw 2 extruded to the inside of the tubular metal container 5 is transported to a predetermined location together with the tubular metal container 5 by a crane or the like. After that, the supply of inert gas was cut off,
After the screw 2 is cooled to a temperature at which it can be taken out, the screw 2 is taken out of the cylindrical metal container 5.

[0020]

Since the present invention is configured as described above, the following effects can be obtained. That is, when the screw is taken out, the screw is extruded into a cylindrical metal container in an inert gas atmosphere, so that ignition and combustion of the molten light alloy material adhering to the screw is eliminated, and therefore the mechanical characteristics of the screw member are reduced. At the same time as preventing the decrease of temperature, the high temperature screw is not exposed and the light alloy material in the molten state is not ignited, burned or drooped, and the screw can be taken out safely.

[Brief description of drawings]

FIG. 1 is a view showing an apparatus for carrying out a screw removing method according to the present invention.

FIG. 2 is a vertical sectional view showing an injection molding device of an injection molding machine.

FIG. 3 is a vertical cross-sectional view showing an injection unit of an injection molding device.

[Explanation of symbols]

1 cylinder barrel 2 screws 3 cylinder head 4 nozzles 5 Cylindrical metal container 6 Inert gas source 7 Piping (Inert gas supply member) 8 Pressure regulator 9 Flow control valve 10 Screw extraction jig

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinji Matsui 1-6-1, Funakoshi Minami, Aki-ku, Hiroshima City, Hiroshima Prefecture, Japan Steel Works, Ltd. (56) Reference JP-A-8-257726 (JP, A) Kaihei 7-155917 (JP, A) JP-A-5-84807 (JP, A) Actual Kaihei 6-66853 (JP, U) Actual Kaihei 4-24318 (JP, U) Registered utility model 3001017 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) B22D 15/00-17/32

Claims (2)

(57) [Claims] 1. A method for taking out a screw of an injection molding machine for injecting a solid light alloy material, wherein a cylindrical metal attached to the tip of a cylinder barrel (1) of the injection molding machine and having an inert gas atmosphere inside. A method for taking out a screw of an injection molding machine, characterized in that the screw (2) is taken out while being inserted into a container (5). 2. A screw take-out device for an injection molding machine for injecting a solid light alloy material, comprising: a cylindrical metal container (5) attached to the tip of a cylinder barrel (1) of the injection molding machine; 5) A screw take-out device for an injection molding machine, which comprises an inert gas supply member (7) for supplying an inert gas into the inside.