JP3472886B2 - Injection molding method and injection molding device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a single mold clamping machine, a plurality of mold units, and a plurality of injection units corresponding to these mold units, for molding. The present invention relates to an injection molding method and an injection molding apparatus used for carrying out this method.

[0002]

2. Description of the Related Art An injection molding method or apparatus is
It is well known in the art without mentioning the name of the literature, and generally comprises an injection unit for melting and injecting a resin material, a mold unit for molding a product, a mold clamping machine for clamping the mold unit, and the like. Therefore, the resin material is melted and kneaded by the injection machine, the mold unit is clamped by the mold clamping machine, and the plasticized resin is injected from the injection unit to the cavity of the mold unit through, for example, the sprue and the gate. After filling and waiting for cooling and solidification to open the movable mold, a synthetic resin molded product or product having a desired shape molded by cavities can be obtained.

[0003]

As described above, a molded article can be obtained by the conventional injection molding apparatus, and if a plurality of injection molding apparatuses, for example, two injection molding apparatuses are used, the main body and the lid, Alternatively, products such as lenses and frames in a magnifying glass which are different in material and have different shapes and different molding cycles can be molded by respective injection molding apparatuses. However, the above molding method is
The use of a table injection molding device inevitably increases the cost of the product. Also, the installation space for the injection molding device becomes wider. As a solution to this problem, if a plurality of, for example, two mold units are applied to one mold clamping machine and two injection units are used corresponding to these mold units, one injection unit will be It is possible to inject a molten resin into the mold unit and to inject a different molten resin from the other injection unit into the other mold unit to form a molded product having a different material and a different shape.

However, the molding method using these two injection units also has a problem. For example, if the type of resin material is different, there is a difference in the cooling and solidification time even if the product has the same shape, and if the shape of the molded product is the product such as the main body and lid, or the lens and frame in the magnifying glass. Generally, since the wall thicknesses are different, there is a difference in the cooling and solidification time, but the above-mentioned molding method cannot deal with this problem. That is, if a single mold clamping machine molds products with different cooling and solidification times, it will be restricted to the longer molding cycle, and the next injection cycle cannot be entered, and expensive injection machines, mold clamping machines, etc. This makes the person waiting, which deteriorates the injection molding efficiency. Therefore, it is an object of the present invention to provide an injection molding method capable of efficiently molding a product having a different material and a different wall thickness and different molding cycles, and an injection molding apparatus used for carrying out the method. I am trying. It is also an object of the present invention to provide an injection molding method that can minimize the installation space of the injection molding apparatus and can contribute to the reduction of product cost at a low cost, and an injection molding apparatus used for carrying out this method.

[0005]

In order to achieve the above object, the present invention provides a single mold clamping machine, a plurality of mold units, and a plurality of mold units corresponding to the respective mold units. Using an injection unit, one mold unit molds a product with a relatively short cooling and solidification time, and the other mold unit molds a product with a relatively long cooling and solidification time and the other mold unit. While the mold is injected and the mold clamping force is maintained in a self-maintaining state, a molding cycle of molding with one mold unit is performed a plurality of times.
The invention according to claim 2 is a plurality of mold units each including a movable mold and a fixed mold, one mold clamping machine for clamping these mold units, and a plurality of mold units corresponding to the mold units. and a base of the injection unit, at least one fixed mold of the mold unit and the movable mold of the mold unit, the mold clamping
Binding and binding in the mold clamped state to each other in connection with the operation to be able of solving <br/>, also the fixed mold is configured to be able to unlock and lock the fixed plate .

[0006]

By using a plurality of mold units, for example, two mold units, the first mold unit and the second mold unit, it is possible to compare a product having a fast solidification in the first mold unit and a solidified product in the second mold unit. Mold products that take a lot of time. One mold clamping machine clamps the first and second mold units. Then, the molten resin is injected into each mold unit. The movable platen is opened after waiting for the solidification of the product injected into the first mold unit. By opening the mold, the product, which is molded by the first mold unit and has a rapid solidification, is taken out. At this time, since the second mold unit is kept in the mold clamped state, the mold is not opened.
Solidification of slow-setting products is progressing. Tighten the mold. Then, the molten resin is injected into the first mold unit. After waiting for the solidification of the product injected into the first mold unit, the movable platen is opened to take out the product which has solidified quickly. As described above, the second
While the mold unit is being held in the mold clamped state, a plurality of molding cycles for molding a product that solidifies quickly are performed. When you take out a product that solidifies quickly, clamp the mold. Then, the molten resin is injected into the first mold unit. The movable platen is opened after waiting for the solidification of the product injected into the first mold unit. This time, the second mold unit is also opened to take out the product which has a slow solidification. The above molding cycle is repeated to form a plurality of products that solidify quickly while molding one product that solidifies slowly.

[0007]

The present invention applies a plurality of mold units to one mold clamping unit.
An example of using a single mold unit 1 and 10 to mold a relatively thin product A in the first mold unit 1 and a thick product B in the second mold unit 10 will be described. To do. Further, according to the present invention, the thin product A and the thick product B can be molded at various molding cycle ratios, the thin product A is twice and the thick product B is thick.
An example of molding at a rate of once will be described. As the resin material, products A and B can be molded with the same resin,
It is also possible to mold with different resins. Since a conventionally known mold clamping machine is applied, a concrete example of the mold clamping machine is not shown in the drawing.

Hereinafter, examples of the present invention will be described. As shown in FIG. 1, the injection molding apparatus according to this embodiment includes two sets of first and second mold units 1 and 10. Then, first and second injection units 30 and 31 are provided corresponding to these mold units 1 and 10.
The first and second injection units 30 and 31 have a known structure, and known injection nozzles 32 and 33 are provided at the tips thereof. The first mold unit 1 located at the upper side in the drawing is composed of a movable mold 2 and a fixed mold 3. As is well known in the art, the movable mold 2 is attached to one common movable plate 4, and the fixed mold 3 is similarly attached to the common fixed plate 6 via the attachment member 5.
A cavity 7 for molding a thin product A is formed in the first mold unit 1, and the cavity 7 communicates with a locate ring 9 via a sprue 8.

The second mold unit 10 located below is also
Similarly, it is composed of a movable mold 12 and a fixed mold 13. The second mold unit 10 is formed with a cavity 17 for molding the thick molded product B, and the cavity 17 is also communicated with the locate ring 19 via the sprue 18. .

According to this embodiment, the second mold unit 10
The fixed mold 13 is separated from or fixed to the fixed platen 6 in conjunction with or in association with the molding cycle, as described in detail in the section of operation. Furthermore, fixed mold 1
3 is also coupled to the movable mold 12 in a mold clamped state as required. The structure can be configured as described in Japanese Patent Application Nos. 4-293911 and 293912, which are currently proposed by the present applicant. Therefore, FIG. 1 shows these examples. Is schematically shown. That is, the attachment member 15 to which the fixed mold 13 is attached is attached to the fixed platen 6 by the lock mechanism. The lock mechanism is schematically shown in the figure with the lock pins 20, 2
1 is shown. The lock pins 20 and 21 are unlocked and locked alternately in relation to the mold clamping operation so that the lock pins 20 and 21 are released by the first mold clamping operation of the movable platen 4 and locked by the second operation. It is like this.

The fixed mold 13 of the second mold unit 10 is also
The mold clamping state is maintained and released from the movable mold 12 as needed, and this mechanism is also disclosed in the above-mentioned Japanese Patent Application Nos. 4-293911 and 293912. Since they can be configured so that they are present, the coupling members 22 and 23 are shown as a representative of these mechanisms. The coupling members 22 and 23 are configured to couple the dies 12 and 13 by the first mold clamping operation of the movable platen 4 and release the dies 12 and 13 by the second operation. That is, the lock pin 2
Contrary to 0 and 21, coupling and releasing are alternately repeated in relation to the mold clamping operation.

Next, an example in which a thin product A and a relatively thick product B are injection-molded by using the above injection molding apparatus will be described. (1) As shown in FIG. 2A, the movable platen 4 is driven and the mold is clamped. Since this mold clamping operation is the first time, the fixed mold 13 of the second mold unit 10 is coupled to the movable mold 12 by the coupling members 22 and 23 by this action. Further, the lock pins 20 and 21 are unlocked, and the fixed mold 13 becomes separable from the fixed platen 6. As is well known, the first mold unit 1 has a first
Molten resin is injected into the cavities 7 and 17 from the nozzle 32 of the injection unit 30 and from the nozzle 33 of the second injection unit 31 to the second mold unit 10. (2) Waiting for the pressure holding and solidification of the fast solidified thin product A molded by the first mold unit 1, the movable platen 4 is driven to open the mold. Since the first mold unit 1 has a conventionally well-known structure, when the mold is opened, the thin product A is ejected by the ejector pin.

On the other hand, the fixed mold 13 of the second mold unit 10 is connected to the movable mold 12 by the connecting members 22 and 23, and the lock pins 20 and 21 are unlocked. When the fixed mold 13 is opened, the movable mold 1
It is maintained in the mold clamped state integrally with 2, and is driven in the mold opening direction. These states are shown in FIG. (3) Since the thin product A has been taken out, the movable platen 4 is driven and the mold is clamped as shown in FIG. Since this mold clamping operation is the second time, this operation causes the fixed mold 13 of the second mold unit 10 to move to the movable mold 12.
The bond with is released. Further, the lock pins 20 and 21 are locked. As described above, the molten resin is injected from the nozzle 32 into the cavity 7 of the first mold unit 1.

(4) Waiting for the pressure and solidification of the thin product A, the movable platen 4 is driven to open the mold. Since this mold opening is the second molding cycle and the time has elapsed, the thick product B molded by the second mold unit 10 is also solidified. When the movable platen 4 is opened, in the first mold unit 1, the thin product A is ejected by the ejector pin as described above. In addition, the coupling members 22 and 23 of the second mold unit 10
2 is released and the lock pins 20 and 21 are in a locked state. Therefore, when the movable platen 4 is opened, the second mold unit 10 is also opened this time, as shown in FIG. Thick product B is also ejected. Since the thin product A and the thick product B have been taken out, the movable platen 4 is ready for the next injection.
Drive to close the mold. Then, as shown in (a) of FIG. Similarly, two thin products A and one thick product B are molded in the same manner.

[0015]

As described above, according to the present invention, one mold clamping machine, a plurality of mold units, and a plurality of injection units corresponding to these mold units are used. Then, one mold unit molds a product with a relatively short cooling and solidification time, and the other mold unit molds a product with a relatively long cooling and solidification time and injects it into the other mold unit. While the mold clamping force is kept self-supporting, it is configured to perform the molding cycle for molding with one mold unit a plurality of times. The effect peculiar to the present invention that molding can be efficiently performed is obtained. Also, 1
It is possible to obtain the effect of simultaneously molding products of different materials with the mold clamping machine of the stand, and further it is possible to efficiently mold products of different materials with different solidification times. Further, according to the present invention, since a plurality of injection units are molded by one mold clamping machine, there is a margin in the layout of the installation space of the injection molding device, and the mold clamping machine is shared. Therefore, the injection molding apparatus is inexpensive and the product cost can be reduced.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view schematically showing an embodiment of the present invention.

FIG. 2 is a diagram schematically showing an operating state of the embodiment of the present invention, and (A) to (D) are partially cutaway front views showing respective molding steps in order.

[Explanation of symbols]

1 1st mold unit 6
Fixed platen 10 Second mold unit 12
Movable mold 13 Fixed mold 20, 2
1 Lock pin 30, 31 Injection unit

Front page continuation (72) Inventor Kunikazu Kazuda 1-6-1, Funakoshi-minami, Aki-ku, Hiroshima City Japan Steel Works (72) Inventor Hiroshi Yonekubo 2-43-2 Hatagaya, Shibuya-ku, Tokyo Ori Inpass Optical Co., Ltd. (72) Inventor Kaoru Maeda 2-43-2 Hatagaya, Shibuya-ku, Tokyo Orimpus Optical Co., Ltd. (72) Inventor Tetsuo Suga 2-43-2 Hatagaya, Shibuya-ku, Tokyo Ori Inpass Optical Industry Co., Ltd. (72) Inventor Kazuo Saito 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Industry Co., Ltd. (56) Reference JP-A-6-114874 (JP, A) JP-A 6-114890 (JP, A) JP-A-1-249415 (JP, A) Actual development Sho 63-100121 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) B29C 45/06 , 45 / 10,45 / 12

Claims (2)

(57) [Claims] 1. A mold clamping machine, a plurality of mold units (1, 10), and a plurality of injection units corresponding to these mold units (1, 10) are used. Then, in one mold unit (1), the product (A) whose cooling / solidifying time is relatively short is used, and in the other mold unit (1).
In (0), a product (B) having a relatively long cooling / solidifying time is molded and injected into the other mold unit (10) to keep the mold clamping force in a self-holding state, An injection molding method characterized in that a molding cycle in which molding is performed by the mold unit (1) is performed a plurality of times. 2. A movable mold (2, 12) and a fixed mold (3,
13) and a plurality of mold units (1, 10)
And clamp these mold units (1, 10) 1
A mold clamping machine and a plurality of injection units (30, 31) corresponding to the mold units (1, 10), and at least one mold unit of the mold units (1, 10) ( 10) fixed mold (13) and movable mold (1)
2) is such that in connection with the clamping operation it is possible to couple (22, 23) and uncouple each other into a clamped state,
The fixed mold (13) is locked (2) to the fixed platen (6).
0, 21) and the lock can be released.