JPH0434006Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application)
The present invention relates to a liquid color supply device for coloring the synthetic resin when it is melted.

(Prior art) Conventionally, when changing the color of synthetic resin injected into a mold from an injection device, the synthetic resin inside the device is changed by the synthetic resin colored in a different color to be used next. After extrusion, a normal injection molding process is performed. When coloring the synthetic resin inside the device, the molten synthetic resin is colored by injecting a liquid pigment coloring agent (hereinafter referred to as liquid color) from the middle of the heating cylinder of the device. .

A conventional injection device equipped with a device for injecting liquid color into molten synthetic resin will be explained with reference to FIG.

The injection device 11 has a heating cylinder 12.
The center flow path has a screw 13 for sending the synthetic resin forward and a mixing 14 for increasing kneading.
and the head 15 are connected and inserted in a line on a coaxial line. A heater 16 is provided on the circumferential surface of the heating cylinder 12, and the outer periphery of the heater 16 is covered with a protective cover 17. A hole is formed from the upper part of the circumferential surface of the heating cylinder 12 toward the flow path, and the lower end of the supply cylinder 18 is fitted into this hole 12a. A liquid color of a desired color is dripped into the supply tube 18 according to the purpose, mixed with the molten synthetic resin by the screw 13, colored, and injected into the mold.

(Problem that the invention aims to solve) However, when supplying liquid color, there is no problem because the liquid color is extruded and colored while applying pressure, but when the supply of liquid color is temporarily stopped, no pressure is applied. Since the liquid collar is merely in contact with the molten synthetic resin within the discharge port of the supply cylinder 18, the synthetic resin flows back into the supply cylinder 18 due to the movement of the synthetic resin by the screw. When the supply of liquid color is restarted, it is sufficient if the synthetic resin that has entered is pushed out as it is, but as shown in Fig. 3, the synthetic resin 19 that has entered the discharge port of the supply tube 18 is solidified due to the influence of the surrounding environment. 19a, the flow path of the liquid color 20 is blocked, making it impossible to supply the liquid color.
This requires a lot of time and effort to disassemble and clean.
It reduces productivity.

In order to solve the above problems, the present invention provides a liquid color supply device that can melt solidified synthetic resin and stabilize the supply.

(Means for Solving the Problems) In order to achieve the above object, the present invention installs a liquid color supply cylinder from the peripheral wall of the heating cylinder of the injection device toward the flow path, and attaches the liquid color supply cylinder to the lower end of the supply cylinder. It is characterized by the installation of a heater that enters the discharge port from inside the heating cylinder and melts the solidified synthetic resin.

(Function) The molten synthetic resin moving inside the heating cylinder to the injection port is colored by the supply of liquid color. When this molten synthetic resin enters the discharge port of the supply cylinder, it solidifies due to the influence of the interface, temperature, etc. and blocks the hole in the supply cylinder, but it solidifies at will by the heater installed at the bottom end of the supply cylinder. It is possible to melt the synthetic resin and extrude the molten synthetic resin at the same time as liquid color is supplied.

(Example) An embodiment of the present invention will be described based on FIG.

FIG. 1 shows the liquid color (liquid pigment coloring agent) supply device as seen from the axial direction of the heating cylinder 2. As shown in FIG. In the figure, reference numeral 1 denotes a supply tube, which is fitted into a hole 2b provided from the outer peripheral surface of the heating tube 2 toward the flow path 2a. In this state, the liquid flow path 1a of the liquid collar 3 of the supply tube 1 passes through the flow path 2a through the discharge hole 1b.
will be communicated with.

Reference numeral 7 denotes a hot chip (heater) holding column arranged in the supply cylinder 1, the upper end of which is fixed to the upper part of the supply cylinder 1, and a liquid flow path 1a is formed around it. A hot chip 8 is attached to the tapered lower end of the hot chip holding column 7, and this portion is positioned at the discharge port at the lower end of the liquid flow path 1a. An electric cord 9 for energizing and heating is connected to the hot chip 8.

In this device configured as described above, even if the molten synthetic resin 5 moving through the flow path 2a flows backward and enters the liquid flow path 1a and solidifies, it can be remelted by heating the hot chip 8. . This can be easily pushed out into the channel 2a by the delivery means of the liquid color 3.

In addition, in the embodiment, the hot chip 8 is attached to the holding column 7.
Although it is attached to the lower end and located at the lower end of the liquid flow path 1a, it may also be provided so as to be arranged in a ring shape at the lower end of the supply cylinder 1.

(Effects of the invention) Since the invention is constructed as described above, even if the synthetic resin flows backwards and enters the inside of the supply cylinder from the discharge port and solidifies, it can be remelted without disassembling the injection device. This will help stabilize the supply of liquid color. Therefore, productivity can be improved by reducing the time and labor required for disassembly and cleaning.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a liquid color supply device which is an embodiment of the present invention, Fig. 2 is a sectional view of an injection device equipped with a conventional liquid color supply device, and Fig. 3 is a sectional view of an injection device equipped with a conventional liquid color supply device.
The figure is a sectional view of a conventional liquid color supply device. 1... Supply tube, 2... Heating tube, 2a... Channel,
8...Hot chip (heater).

Claims (1)

[Scope of utility model registration request] A liquid color supply tube is attached from the peripheral wall of the heating tube of the injection device toward the flow path, and a heater is attached to the lower end of the supply tube for melting the solidified synthetic resin that enters the discharge port from inside the heating tube. A liquid color supply device characterized by: