JPS6017299Y2 - Resin material injection port of synthetic resin injection mold - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of the resin material injection port of the Hewei resin injection mold, which incorporates a heat pipe to maintain the molten state of the resin material to be injected.

This type of resin material injection port incorporates a heat pipe in order to maintain the molten state of the resin material to be injected until it reaches the cavity.
62 (Japanese Unexamined Patent Publication No. 50-23459).

However, in this conventional means, as shown in FIG. The heat pipe 11 is assembled in a buried state inside the mold 13, and the heat pipe 11 is expensive because the hot runner-b is assembled into the mold 13. Since hot runner B acts as a heat source for the synthetic resin material, if a failure occurs in the heat source of hot runner b, the resin material may not be injected smoothly, and repairs and repairs may be difficult.
Repairs and maintenance to avoid this problem are difficult, and furthermore, when used in an existing mold that does not have a heat pipe, there is a problem in that major modifications must be made.

In addition, as shown in Figure 1, some injection molds do not use a hot runner or a heat pipe, but in this mold one part of the sprue and part two of the runners are used together with the cavity 3. The first part of the sprue in particular uses a large amount of resin material, and the cooling time for solidification is long, resulting in a long shot cycle, which wastes resin material and has a large impact on productivity.

The present invention was devised in order to solve these problems in the conventional technology, and has a simple structure and easy maintenance of a heat pipe for maintaining the molten state of the resin material to be injected. Provides a new resin material injection port for a new resin injection mold that can be easily incorporated into existing molds that do not have a heat pipe. The purpose is to

In order to achieve this objective, in this invention,
A sprue bushing in which a cylindrical space has a guide path that is narrowed in the shape of a funnel at the outlet is opened at the axis, and the sprue bushing is installed in a mold die plate so that the outlet of the guide path communicates with the cavity. The nozzle has an ejection port of approximately the same diameter and is assembled with the axis aligned with the entrance of the guideway, the nozzle is attached to the tip, an injection screw is built in, and the outer periphery is surrounded by a heater. A heat pipe is formed by a molding machine cylinder and a heat pipe held within a guide path of the sprue bushing, with one end approaching the outlet of the guide path and the other end passing through the nozzle and facing into the molding machine cylinder. The present invention proposes a means for configuring a resin material injection port of a resin injection mold.

Next, embodiments will be described in detail with reference to the drawings.

Note that the same reference numerals are used for parts common to the conventional one.

In Figures 2 and 3, 4 is a sprue bushing,
A guide path 5 is provided in the axial direction.

The guide path 5 has a cylindrical shape, but narrows into a funnel shape on the exit 5a side.

The sprue bushing 4 is detachably installed on the mold guide plate 6, and when installed, the outlet 5a of the guide path 5 communicates with the cavity 3.

In the example shown in FIG. 2, the outlet 5a communicates with a number of cavities 3 through runners 2, and in the example shown in FIG. 3, it communicates directly with the cavities 3.

4a is a flange projecting in the radial direction from the outer peripheral edge of the sprue bushing 4.

5b is a fitting part formed on the entrance side of the guide path 5, into which the tip of the nozzle 7 of the injection molding machine fits.

The nozzle 7 of the injection molding machine is attached to the tip of the molding machine cylinder 8, and the inner diameter of its ejection port is approximately equal to the diameter of the guide path 5 of the sprue bushing 4.

The molding machine cylinder 8 is equipped with the nozzle 7 at its tip, has an injection screw 9 built therein, and is surrounded by a heater 10 on its outer periphery.

Reference numeral 11 denotes a heat pipe whose both ends are streamlined, the outer diameter of which is smaller than the diameter of the guide path 5 of the sprue bushing 4, and the guide path 5 is connected to the outer periphery of the heat pipe 11 by a holding piece 12. The one end 1 of the heat pipe 11 is held so that a passage is formed between it and the inner circumferential surface of the guide path 5.
It is held so that one end 1a approaches the outlet 5a of the guide path 5 and the other end 11b passes through the inside of the nozzle 7 and faces into the cylinder 8.

13 and 14 are inner and outer molds forming the cavity 3.

A molten resin 15 is molten in the cylinder 8 by the heater 10 .

The resin material injection port of the Hewei resin injection mold according to the present invention constructed as described above operates as follows.

The assembled heat pipe 11 is injection molded with one end 11a facing the outlet 5a of the guide path 5 in the sprue bushing 4 that feeds the molten resin material 15 into the cavity 3, and the other end 11b protruding from the entrance side of the guide path 5. Since it faces the inside of the molding machine cylinder 8 through the spout lumen of the nozzle 7 of the machine, the heat received from the resin material in the molding machine cylinder 8 which becomes molten due to the peak-10 surrounding the molding machine cylinder 8,
The resin material carried near the exit 5a of the guide path 5 facing the cavity 3 and injected into the guide path 5 by the injection screw 9 is heated throughout the guide path 5 by heat from the heater 10 surrounding the molding machine cylinder 8. The resin material 15 is uniformly heated and maintained in a molten state so that the resin material 15 to be injected is cooled and solidified only within the cavity 3.

That is, the heat pipe 11 to be incorporated uses the heat of the heater 10 around the molding machine cylinder 8 provided in the injection molding machine, without incorporating a heater as a heat source in the mold side.
The resin material 15 injected from the injection molding machine is maintained in a molten state to prevent it from solidifying on the way to the cavity 3.

The heat pipe 11 that operates in this manner is as described above.
Since it is attached so as to extend from the inner cavity of the nozzle 7 at the tip of the molding machine cylinder 8 to the guide path 5 of the inner cavity of the sprue bushing 4 attached to the mold die plate 6, the structure is as shown in FIG. The sprue bushing of the present invention is constructed by removing the sprue bushing 4 attached to the mold die plate 6 of the existing one without the heat pipe 11, as shown in Fig. 2. By installing 4 interchangeably, it can be easily used in existing molds.

Furthermore, the guide path 5 in the sprue bushing 4 that accommodates the heat pipe 11 becomes substantially an extension of the molding machine cylinder 8 of the injection molding machine due to the heat pipe 11, and the outlet 5a of the guide path 5 is is essentially the spout of the nozzle 7, so the actual sprue consists of only a very short outlet 5a as shown in Fig. 2. Conventionally, the diameter of the sprue gradually increases toward the injection direction for heat retention. The sprue that was formed and installed in this manner has been substantially removed.

Therefore, according to the means of the present invention, a temperature control device, an electric heater, etc. can be added to the resin material injection port of the resin injection mold, which maintains the resin material injected by the heat pipe in a uniform molten state. The heat pipe has a simple configuration in which the heat pipe is assembled to the outside of the mold for easy maintenance and does not require any major modifications. In addition, since there is virtually no sprue, productivity is improved by saving resin materials and shortening the shot cycle.Furthermore, since there is no need to modify the inside of the mold, etc., it can be removed from the outside. By standardizing only the removable sprue bushings in size, you can also benefit from being able to use them in common with other types.

[Brief explanation of drawings]

Figure 1 is a longitudinal sectional view of the resin material injection port of the existing Hewei resin injection mold, and Figure 2 is the resin material injection port of the Hewei resin injection mold, which is the first embodiment of the present invention. FIG. 3 is a vertical cross-sectional view of the resin material injection port of the second embodiment of the present invention, a resin injection mold, and FIG. FIG. 2 is a longitudinal cross-sectional view of a resin material injection port of a resin injection mold. Explanation of drawing symbols, 1... Sprue part, 2...
...Runner (part), 3...Cavity, 4.
...Sprue bushing, 4a...Flange, 5...Guideway, 5a...Exit, 5
b... Fitting part, 6... Mold die plate, 7... Nozzle, 8... Molding machine cylinder, 9... Injection screw 10...
・Heater, 11...Heat pipe, 11a・
...One end, 11b...Other end, 12...
...Holding piece, 13.14...Inner and outer mold, 1
5... Molten resin.

Claims (3)

[Scope of utility model registration request] (1) A sprue bushing 4 having a guide path 5 whose cylindrical space narrows in the shape of a funnel at the outlet 5a is opened around the axis, and the sprue bushing 4 is installed on a mold die plate 6 to form the guide path 5. A nozzle 7 is provided with an ejection port of approximately the same diameter, and the nozzle 7 is assembled with the axis aligned with the inlet of the guide path 5 with the outlet 5a communicating with the cavity 3, and the nozzle 7 is attached to the tip. A molding machine cylinder 8 having a built-in injection screw 9 and surrounded by a heater 10 on the outer periphery.
Then, the sprue bushing 4 is held in the guide path 5 so that one end 11a approaches the outlet 5a of the guide path 5 and the other end 11a approaches the outlet 5a of the guide path 5.
1b comprises a heat pipe 11 passing through the nozzle 7 and facing into the molding machine cylinder 8. (2) Resin material for the resin injection mold according to claim 1, wherein the exit 5a of the guide path 5 communicates with a plurality of cavities 3 via the runner 2. Inlet part. (3) The resin material inlet portion of the joint resin injection mold according to claim 1, wherein the exit 5a of the guide path 5 directly communicates with the cavity 3.