JPH04147818A - Mold for molding synthetic resin - Google Patents

Abstract

PURPOSE:To prevent the generation of stringing and an inferior product and to control the flow rate between a plurality of spools by controlling the opening and closing of the synthetic resin injection flow path in a mold and the opening and closing degree thereof by the operation of a disc-shape valve. CONSTITUTION:A connection shaft 26 and a guide piece 29 are retracted to rotate a disc-shape valve 16 so as to allow valve ports 19, 19, 19 to communicate with valve seat ports 20, 20, 20 and a molten synthetic resin is introduced into the synthetic resin injection flow path 11 from an injection molding machine under pressure to be injected in a cavity 4 through a runner 13. The operating shaft 25 of an actuator 24 is stretched to allow the connection shaft 26 and the guide piece 29 to advance and the disc-shape valve 16 is rotated to shift the valve ports 19, 19, 19 from the valve seat openings 20, 20, 20 of a valve box 15 to cut off, the communication of the valve ports and the valve seat openings. When a mold is opened after the synthetic resin is cooled and solidified, various troubles due to the generation of a stringing phenomenon is prevented. By controlling the stroke of an operating shaft 25 and the angle of rotation of the disc-shape valve 16 by a control screw 31, the opening area of the flow path can be controlled and the inflow balance of the resin in a mold can be controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to the structure of a synthetic resin injection nozzle in a synthetic resin mold.

[Problems with conventional technology] When a molded product is removed from a mold in synthetic resin injection molding, the unsolidified filamentous resin that is drawn out from the spool along with the molded product can adhere to the surface of the molded product and cause the molded product to be defective. Otherwise, they could invade the sliding parts of the mold and cause malfunction. Furthermore, when molding a molded product using a plurality of spools, it is necessary to adjust the flow rate of the synthetic resin between the spools, but it is difficult to do this appropriately.

For this reason, improvement has been desired for some time, but an appropriate means has not yet been developed.

[Means for Solving the Problems] The synthetic resin molding mold of the present invention is intended to solve the above-mentioned problems. Accordingly, a disk-shaped valve that rotates in a plane perpendicular to the flow path is provided, and the synthetic resin injection flow path can be opened and closed and the degree of opening and closing can be adjusted by the disk-shaped valve.

[Example] Next, one embodiment of the present invention will be described with reference to the drawings.

Figure 1 shows a vertical cross-sectional view of this mold. 1 in Figure 0 is a fixed type;
2 is a movable mold, 3 is a parting line thereof, 4 is a cavity, 5 is a locate ring of a fixed mold 1 for properly pressing the tip of the heating cylinder of the injection molding machine into the synthetic resin injection channel 11, and 8 is the fixed mold. A nozzle 9 disposed in the nozzle 1 is a spool member connected to the tip of the nozzle 8 via a threaded portion 10. For this reason, a synthetic resin injection flow path 11 is formed in the fixed mold 1 that extends from the nozzle 8 to the spool member 9. A bunt heater 12 is wound around the outer periphery of the nozzle 8 to keep the synthetic resin injection channel 11 within the nozzle 8 at a high temperature to prevent the synthetic resin flowing through the synthetic resin injection channel 11 from solidifying. . A synthetic resin injection channel 11 within the spool member 9 communicates with the cavity 4 via a runner 13. Note that reference numeral 14 indicates an assembly member that holds the spool member 9 within the fixed mold 1.

A valve box 15 is disposed in the spool member 9 at the connection part with the nozzle 8, and a disk-shaped valve 16 that can rotate in a plane perpendicular to the synthetic resin injection channel 11 is disposed within the valve box 15. establish. Reference numeral 17 denotes a valve cover that closes the disk-shaped valve 16 within the valve box 15, and a communication port 18 with the synthetic resin injection channel 11 of the nozzle 8 is opened in the valve cover 17. The disc-shaped valve 16 has an opening with the same diameter as the communication port 18 on the side facing the valve lid 17, and three small valve ports 19, 19, 19 open on the side facing the inner bottom surface of the valve box 15. The flow path branches into three forks. Further, the inner bottom surface of the valve box 15 is arranged so that the spool member 9 can face the valve ports 19, 19, 19.
The valve seat opening 2 has a three-pronged shape that communicates with the synthetic resin injection flow path 11 inside.
0,20.20 has been opened. The pin 21 fixed to the circumferential side of the disc-shaped valve 16 is connected to a long hole 21 formed in the side wall of the valve body 15 and the spool member 9 to be elongated in the circumferential direction.
A slider 23 is fixed to the protruding end of the pin 21 passing through it. 24 is an actuator such as an air cylinder fixedly installed in the fixed mold 1, and an operating shaft 25 of the actuator 24
A connecting shaft 26 provided in parallel with the actuating shaft 25 is connected by a connecting fitting 27, and when the actuating shaft 25 moves forward or backward due to the operation of the actuator 24, the connecting shaft 26 moves forward or backward integrally. has been done. Note that 28 is the connecting shaft 26
This is a bearing piece. As shown in FIG. 5, a bifurcated guide piece 29 that covers the outer periphery of the spool member 9 is provided at the tip of the connecting shaft 26, and the slider 23 is provided on the inner surface of the guide piece 29. An inclined guide groove 30 is formed into which the guide groove 30 is loosely fitted. Therefore, when the actuator 24 is actuated, the connecting shaft 26. When the guide piece 29 moves forward or backward, the slider 23 slides along the guide groove 30, and the disc-shaped valve 16 connected by the pin 21 can rotate. In addition, 31 is the operating shaft 25
is provided opposite to the tip of the operating shaft 25 in order to adjust the stroke of the ! The gi1 node screw 32 is a key that fixes the valve box 15 in a non-rotatable manner.

In the synthetic resin molding mold configured in this way, the connecting shaft 26. The guide piece 29 is moved back and the disc-shaped valve 16 is rotated so that its valve port 19, 19.19 communicates with the valve seat port 20°20.20, and the synthetic resin injection channel 11 is inserted from the injection molding machine. A molten synthetic resin is press-fitted into the cavity 4 through a runner 13. Then, the operating shaft 2S of the actuator 24 is extended, and the connecting shaft 26. By advancing the guide piece 29, the disk-shaped valve 16 is rotated, and its valve openings 19, 19.19 and the valve seat opening 2 of the valve body 15 are rotated.
0, 20.20, the communication is closed. and cavity 4. After waiting for the synthetic resin in the synthetic resin injection channel 11 in the runner 13 and the spool member 9 to solidify due to cooling, the mold is opened. Since the injection flow path 11 is separated from the injection flow path 11 by the disc-shaped valve 16, the uncured resin does not turn into strings and are pulled out together with the molded product, thereby preventing various troubles caused by the stringing phenomenon. In addition, by adjusting the stroke of the operating shaft 25 and the rotation angle of the disk-shaped valve 16 using the adjustment screw 31, the valve openings 19, 19° 19 and the valve seat openings 20, 20, 2
Since the opening area of the flow path can be adjusted by matching with 0, the balance of resin inflow into the mold can be adjusted.

[Effects of the Invention] As described above, the synthetic resin molding mold of the present invention can open and close the synthetic resin injection channel in the mold and adjust the degree of opening and closing by operating the disc-shaped valve. It is possible to prevent so-called stringing, eliminate the occurrence of defective products, and adjust the flow rate between a plurality of spools. In addition, since the disc-shaped valve is provided to rotate in a plane perpendicular to the synthetic resin injection flow path, it cannot be used with other types of valve sliding parts, such as when using a sliding gate valve. There is no risk of molten resin entering the gap and solidifying it, which could cause a failure, and maintenance is therefore easy.

[Brief explanation of the drawing]

The drawings show an embodiment of the synthetic resin molding mold according to the present invention, in which FIG. 1 is a longitudinal cross-sectional view, FIG. 2 is an enlarged view of the main part thereof, and FIG. 3 is a view taken along A--A in FIG. The A-line sectional view, Figure 4 is B-BA in Figure 2! 5 is a sectional view taken along the line CC in FIG. 2, and FIG. 6 is a sectional view taken along the line D-D in FIG. 2. DESCRIPTION OF SYMBOLS 1... Fixed type, 2... Movable type, 4... Cavity, 8... Nozzle, 9... Spool member, 11... Synthetic resin injection channel, 15... Valve box, 16. ...Disk valve, ...Valve lid. Patent applicant Hideo Murotani

Claims (1)

[Claims] 1. A disk-shaped valve that rotates in a plane perpendicular to the flow path is provided in the synthetic resin injection flow path formed in the synthetic resin molding mold, and the amount of rotation of the disk-shaped valve is adjusted. A mold for molding synthetic resin, characterized in that the resin injection channel can be opened and closed, and the degree of opening and closing can be adjusted.