JPH02147309A - Injection molding machine - Google Patents

Abstract

PURPOSE:To smoothly perform continuous molding and to achieve miniaturization by mounting one injection condition control apparatus provided in relation to one nozzle common to two sets of molds and a computer control means for controlling the injection condition control apparatus so as to alter the injection condition from the nozzle corresponding to the molds. CONSTITUTION:A lower mold 16 is formed from the first lower mold 18 and the second mold 20 and the upper mold 22 common to the first and second lower molds 18, 20 is combined with the lower mold 16. By this constitution, two sets of molds are formed by the lower mold 16 and the upper mold 22 and the leading end outlet of a nozzle 30 is arranged to the injection port 22a of the upper mold 22 and an injection condition mold 22 and an injection condition control apparatus 34 for controlling an injection condition allowing the resin supplied from a pipe 32 to flow in the closed space of a mold 12 in relation to said nozzle 30 is arranged. The injection condition control apparatus 34 adjusts or controls the pressure, flow velocity and amount of the resin to be injected and a computer control apparatus 36 is connected to said injection condition control apparatus 34 and the program of several kinds of different injection conditions is preset to the computer control apparatus 36.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an injection molding machine, and particularly to a novel injection molding machine that continuously molds with different sets of molds and under different molding conditions.

[Prior art]

For example, as in the piezoelectric sounder already proposed by the applicant (Japanese Patent Application No. 1983-249596, filed on October 3, 1988), the same type of resin is molded at least twice to form a single product. The most basic way to make a
It is conceivable to use two injection molding machines and perform injection molding in each. However, with this method,
Continuous molding is not only difficult, but also costly and requires a large installation space.

On the other hand, a rotary type (or sliding type) injection molding machine as shown in FIG. 3 is also known. In the example shown in FIG. 3, a lower mold 1 and an upper mold 2 are combined to define different closed spaces 3 and 3', respectively. That is, first, a closed space 3 is formed and initial molding is performed using the nozzle 4 and injection condition adjustment device w5, and then the lower mold 1 is rotated (or slid) to form another closed space 3'. Molding is performed using another nozzle 4' and injection condition adjusting device 5.

[Problem to be solved by the invention]

In the conventional technique shown in FIG. 3, continuous molding can be performed relatively smoothly, but the nozzles 4 and 4' and the injection conditions (
Injection condition adjusting devices 5 and 5' were required to adjust the injection conditions (pressure, speed, amount, etc.).

Therefore, in the conventional technology, the cost of the injection molding machine itself becomes high and the machine size becomes large.

Therefore, the main object of the present invention is to provide an injection molding machine that can perform continuous molding smoothly, is inexpensive, and can be downsized.

[Means to solve the problem]

This invention includes at least two sets of molds, one nozzle common to the molds, one injection condition adjustment device provided in relation to one nozzle, and an injection conditioner that changes injection conditions from the nozzle according to the mold. This is an injection molding machine equipped with computer control means for controlling a conditioning device.

[Effect]

The computer control means is programmed in advance with the number of injection conditions (pressure, speed, amount, etc.) necessary for molding using each set (and one set of molds is used for one injection process). In order to perform molding under the specified conditions, the computer control means controls the injection condition adjusting device according to a predetermined program.

Therefore, molding is performed using the set of molds under the set injection conditions.

If the mold is configured as a rotary type or slide type, for example, the lower mold is rotated or slid to prepare another set of molds. Then, the computer control means switches the program, controls the injection condition adjusting device according to another program, and sets the injection conditions necessary for the other set of molds. Therefore, molding is performed using another set of molds under different injection conditions, and, if necessary, the molding is repeated using another set of molds and injection conditions to complete the product.

(Effects of the Invention) According to the present invention, a common nozzle and an injection condition adjustment device are provided for different groups, and the injection conditions from the nozzle are changed according to the mold by means of a computer control means. It is not necessary to change the set of nozzle and injection condition adjusting device for each molding process as in the conventional technique shown in the figure, and therefore continuous molding can be performed even more smoothly.

Furthermore, since only one set of nozzle and injection condition adjustment device is required, it is expected that the cost and size of the injection molding machine will be reduced.

The above objects, other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

〔Example〕

Referring to FIG. 1, it should be pointed out in advance that although the injection molding machine 10 of this embodiment is for manufacturing the piezoelectric sounder mentioned above, the target product is not limited to this.

The injection molding machine 10 includes a rotary mold 12. The mold 12 includes a lower mold 16 supported by a shaft 14, and the lower mold 16 is formed with a first lower mold 18 and a second lower mold 20 for defining closed spaces of different shapes. . In this embodiment, the first lower mold 18 and the second
An upper mold 22, which is common to the lower mold 20, is combined with the lower mold 16. However, another upper mold may be used.

The first lower mold 18 is provided with an ejector pin 24 for extruding the molded product. Further, the upper mold 22 is also provided with a similar ejector bin 26, and the first lower mold 1
A holding pin 28 is provided to cooperate with the holding pin 8 to firmly hold an electrode terminal 38 (FIG. 2A), which will be described later, in the closed space.

Furthermore, an injection port 22a is formed on the side surface of the upper mold 22.

In this way, two sets of molds are formed by the lower mold 16 and the upper mold 22.

A tip outlet of a nozzle 30 is arranged at the injection port 22a of the upper mold 22, and a vibrator 3 is connected to the nozzle 30.
An injection condition adjustment device 34 is installed to adjust injection conditions for injecting the resin supplied from the mold 12 into the closed space of the mold 12. The injection condition adjustment device 34 controls the pressure and flow rate of the resin to be injected.

It adjusts or adjusts the amount, etc. A computer control device 36 is connected to this injection condition adjustment device 34,
With reference to FIGS. 2A to 2E, in which programs for several different injection conditions are preset in the computer control device 36, the piezoelectric sounder 46 (
A method of manufacturing the product (Fig. 2E) through two molding steps will be explained. Hereinafter, in order to simplify the drawings, illustrations of the nozzle 30 and the like are omitted in FIGS. 2A to 2E.

First, as shown in FIG. 2A, the upper mold 22 is placed on the first lower mold 18 with the electrode terminals 38 sandwiched therebetween.

Then, as shown in FIG. 2B, the first lower mold 18 and the upper mold 2
2 to form a closed space into which the resin is to be injected, and the electrode terminal 38 is held together by the holding pin 28 of the upper mold 22 and the end of the upper mold 22 and the first lower mold 18. Fix it. Thereafter, resin is injected into the above-mentioned closed space through the injection port 22a formed in the upper mold 22. At this time, the computer control means 36 reads out the program necessary for injection in this case, and according to the program,
Controls the injection condition adjustment device 34. In this way, a molded product in which the electrode terminals 38 are insert-molded, ie, a case 40 of the piezoelectric sounder 46, as shown in FIG. 2B, is formed. After that, the ejector 24 pushes up the upper mold 2.
2 with the case 40 remaining, the first lower mold 18 and the upper mold 2
Open 2.

Next, as shown in FIG. 2C, the lower mold 16 is rotated and the second lower mold 20 is placed directly below the upper mold 22. At this time,
Inside the second lower mold 20, there is a piezoelectric sounding body (a piezoelectric body and a vibrating metal plate laminated together) 42 having a substantially disk shape, for example.
is placed.

Then, as shown in FIG. 2D, the second mold 20 and the upper mold 2
Integrate 2. After that, the injection port 22 of the same upper mold 22
A second molding is performed by pouring the resin into the closed space formed by the second lower mold 20 and the upper mold 22 according to the injection conditions changed by the computer control device 36 from step a. Thereby, the piezoelectric sounding body 42 is insert molded into the case 40. Note that a space 44 is formed between the case 40 and the piezoelectric sounding body 42.

Note that another injection port of the upper mold 22 may be used for the second injection. In this case, it may be necessary to reconnect the nozzle 30.

After that, as shown in FIG. 2E, the second lower mold 20 and the upper mold 2
2, the completed piezoelectric sounder 46 is released from the first lower mold 20 by an ejector pin (not shown), and is also released from the upper mold 22 by the ejector bin 26. A piezoelectric sounder 46 is thereby formed.

In addition, in the above-mentioned embodiment, a case was explained in which two sets of molds consisting of two lower molds and one upper mold were used.
The invention is not limited to this, and two lower molds and two upper molds may be combined, and the combination of lower molds and upper molds is three.
There may be more than one set.

[Brief explanation of the drawing]

FIG. 1 is an illustrative view showing an embodiment of the present invention. FIGS. 2A to 2E are process diagrams showing a method for manufacturing a piezoelectric sounder according to the present invention, in which FIG. 2A shows a state in which an electrode terminal is sandwiched between a first lower mold and an upper mold, and FIG.
The figure shows the first injection state, Fig. 2C shows the upper mold placed on the second lower mold, Fig. 2D shows the second injection state, and Fig. 2E shows the completed piezoelectric sounder. shows. FIG. 3 is an illustrative diagram showing the prior art. In the figure, 10 is an injection molding machine, 12 is a mold, 16 is a lower mold, 18 is a first lower mold, 20 is a second lower mold, 22 is an upper mold, 3
0 is a nozzle, 34 is an injection condition adjustment device, and 36 is a computer control device. Patent Applicant Murata Manufacturing Co., Ltd. Agent Patent Attorney Yama 1) Yoshihito Figure 2A Figure 2C Portion 2D

Claims (1)

[Scope of Claims] At least two sets of molds, one nozzle common to the molds, one injection condition adjusting device provided in relation to the one nozzle, and adjusting injection conditions from the nozzle according to the mold. An injection molding machine comprising computer control means for controlling the injection condition adjusting device to change the injection conditions.