JPH0422414B2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a mold for an injection molding machine.

(Prior art) Synthetic resin products formed by injection molding are
In recent years, its products have diversified, and in order to respond to this,
There is a need for an injection molding machine that has excellent mold compatibility and can be used for a variety of purposes.

The injection molding equipment shown in Figs. 3 and 4 meets the above requirements by making it easy to replace molds, and by making it possible to convert between 2-plate type and 3-plate type with one machine. It is constructed so that it can be used for various purposes (Special Publication No. 62-24245). FIG. 3 shows the state in which it is used as a two-plate type, and FIG. 4 shows the state in which it is used as a three-plate type.

In FIG. 3, numeral 1 is a fixed-side mold plate that holds the fixed-side insert mold 2, 3 is a runner stripper plate, and 4 is a fixed-side mounting base. The fixed side mount 4 is fixed to the injection molding machine, but the fixed side mold plate 1 and the runner stripper plate 3 are slidable on the tie bars. Reference numeral 5 denotes a movable mold plate slidably provided on tie bars 6, into which is fitted a movable mold plate 7 that fits into the fixed mold mold 2 when the mold is closed. Reference numeral 8 denotes a first runner portion that is connected to the movable nesting mold 7 and is provided on the parting surface.

A runner plate 9 is interposed between the fixed side mold plate 1 and the runner stripper plate 3, and a second runner portion 10 is formed. Reference numeral 11 denotes a hot runner portion that opens facing the parting surface of the fixed mold plate 1 and the movable mold plate 5, and 12 denotes a nozzle touch portion with which the nozzle 13 of the injection device comes into contact when injecting resin from the injection device. . Reference numeral 14 denotes a hot pull fixed side mounting base interposed between the back surface of the hot runner section 11 and the runner stripper plate 3;
It is closed to prevent resin from flowing into the second runner section 10 during molding.

With the above configuration, the fixed side template 1 and the movable side template 5
The resin injected with the mold closed passes through the hot runner section 11 and the first runner section 8, and is filled into the stationary insert mold 2. In this configuration, the parting surface is between the fixed template 1 and the movable template 5. That is, it operates as a two-plate type.

On the other hand, in the configuration shown in FIG. 4, the hot runner part 11 is supported by a sprue bush 15 and is placed in a retreated position at the rear of the fixed side mold plate 1, and a second A runner distribution plate 16 forming a resin path communicating with the second runner section 10 is installed.

According to the configuration shown in FIG. 4, the resin injected from the injection device passes through the hot runner section 11, passes through the second runner section 10, and is then formed by the fixed side nesting mold 2a and the movable side nesting mold 7a. filled into the cavity. When opening the mold, the molded product is taken out by opening the mold on the parting surface between the fixed side mold plate 1 and the movable side mold plate 5, and the parting surface between the fixed side mold plate 1 and the runner stripper plate 3 is taken out. The runner is removed by opening the mold on the parting surface.
That is, the configuration shown in FIG. 4 operates as a three-plate type.

In the conventional example described above, the hot sprue fixed side mounting base 14, the sprue bush 15, the runner distribution plate 16
It is possible to convert between the 2-plate type and the 3-plate type by simply replacing the resin path switching member. Furthermore, by manufacturing the stationary side nesting mold in a standard size, it can be easily replaced by fitting it into the stationary side mold plate.

(Problems to be Solved by the Invention) In conventional injection molding machines having both two-plate type and three-plate type functions, as described above, the member for switching the resin path has to be replaced to
I am trying to convert between plate type and 3 plate type. However, during this conversion,
There is a problem in that it becomes complicated to replace the member for switching the resin path each time in addition to replacing the stationary side nesting mold. Therefore, if the 2-plate type and the 3-plate type can be made interchangeable without replacing the member for switching the resin path, workability can be greatly improved.

Therefore, the present invention has been made to solve the above-mentioned problems, and its purpose is to omit the work such as replacing the member for switching the resin path during conversion, and to make it possible to switch between the 2-plate type and the 3-plate type. To provide a mold for an injection molding machine that can be easily converted and used.

(Means for Solving the Problems) In order to achieve the above object, the present invention has the following configuration.

That is, a fixed mold including a fixed side mounting base having a resin path for resin injection, a runner stripper plate, and a fixed side mold plate loaded with a fixed side nested mold;
In a mold for a three-plate injection molding machine, which includes a movable mold mount and a movable mold including a movable mold plate into which a movable nested mold is inserted, the resin outlet of the resin path is located on the fixed side. The injection plunger is provided on the tip surface of the injection plunger that protrudes from the mounting base toward the rear surface of the fixed-side nested mold, and when the mold is closed, the tip of the injection plunger is installed on the fixed side of the runner stripper plate. A through hole through which the tip of the injection plunger slides and passes is bored in the runner stripper plate so as to protrude from the nesting side surface, and the runner stripper plate is inserted into the runner stripper plate with respect to the fixed side mounting base. A tightening means is provided for releasably fixing the plate and the fixed side mold plate, and the runner stripper plate and the fixed side mold plate are fixed to the fixed side mounting base by the fastening means, and the mold plate is fixed to the fixed side mounting base. When using the runner stripper plate as a two-plate type, the fixed side inlet is connected to the resin outlet of the resin path opened at the tip surface of the injection plunger protruding from the fixed side nesting mold side surface of the runner stripper plate. It is characterized in that the resin inlet of the communication path communicating with the cavity part of the child mold is opened at the rear surface of the fixed side nesting mold.

If a concave groove is formed on the outer circumferential surface of the tip of the injection plunger to prevent the runner from returning, it is suitable for removing the runner when the injection plunger is used as a three-plate type.

(Function) During molding, the movable mold plate and the fixed mold plate are brought into contact with each other to close the mold, and resin is injected through the resin path in the fixed side mount and the injection plunger. The resin injected from the end face of the injection plunger passes through the communication path, fills the cavity, and is molded.

It can be used as a 2-plate type by fixing the stationary template and the runner stripper plate to the stationary mount with a fastening means, and it can be used as a 3-plate type by releasing the fastening means.

(Embodiments) Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

1 and 2 are explanatory diagrams showing one embodiment of a mold for an injection molding machine according to the present invention. FIG. 1 is an example in which it is used as a 2-plate type, and FIG. 2 is an example in which it is used as a 3-plate type. This is an example used.

In the figure, 20 is a fixed side mold plate into which the fixed side nesting mold 22 is fitted, 24 is a runner stripper plate, and 26
is the fixed side mounting base. 28 is the movable side nesting mold 30
32 is a movable side mounting base that supports the movable side template. Said fixed side mounting base 2
6 is fixed to the body of the injection molding machine, and the fixed side template 2
0, the runner stripper plate 24, the movable template 28, and the movable mounting base 32 are each slidably supported on a tie bar 34.

When the fixed side template 20 and the runner stripper plate 24 are used as a two-plate type, they are fixed to the fixed side mount 26 by a fastening means. As the tightening means, projections are extended from the outer surfaces of the fixed-side mounting base 26 and the fixed-side mold plate 20, respectively, and these projections are engaged to tighten and fix, or the fixed-side mounting is performed using a fixing bolt. stand 2
6, a method of tightening and fixing the fixed side mold plate 20 and the runner stripper plate 24 can be used.

Next, the structure of the communication part between the fixed side nesting mold 22 and the fixed side mounting base 26 will be explained. 22a is a cavity part provided in the fixed side nesting mold, and this cavity part 22a is connected to the movable side nesting mold 30. Together with this, it forms a molding cavity. 22b is a recess provided on the stationary side nesting die 22 facing the runner stripper plate 24. Recess 22b
A communication path 22c that communicates with the cavity portion 22a is opened at the inner bottom surface.

26a is the fixed side nesting mold 2 from the fixed side mounting base 26.
It is an injection plunger provided to protrude in two directions. A through hole 24a into which an injection plunger 26a is inserted is provided in the runner stripper plate 24, and the tip of the injection plunger 26a passes through the through hole 24a and projects into the recess 22b of the stationary nesting die 22. do. The end surface of the injection plunger 26a is formed into a flat surface, and comes into contact with the inner bottom surface of the recess 22b, which is also formed into a flat surface, when the mold is closed. 2
6b is the injection plunger 26a and the fixed side mounting base 26
This is a resin path provided through the. Resin path 26
The position of the opening on the end face of the injection plunger 26a in b coincides with the position of the hole 22 that opens on the inner bottom face of the recess 22b. The rear opening of the fixed side mount 26 is formed as a nozzle touch part 26c, on which the nozzle 38 of the injection device 36 approaches and separates.

To explain the operation of the embodiment shown in FIG. 1 above,
The fixed side mold plate 20 and the runner stripper plate 24 are fixed to the fixed side mounting base 26 by a tightening means, and the movable side mold plate 28 is advanced with respect to the fixed side mold plate 20 to close the mold. After, injection device 3
The nozzle 38 of No. 6 is brought into contact with the nozzle touch portion 26c to inject resin into the resin path 26b. Resin is hole 2
2c and is filled into the cavity 22a. When opening the mold, the mold is opened on the parting surface of the stationary mold plate 20 and the movable mold plate 28, and the product attached to the stationary nested mold 22 is released by known means such as ejection pins. . In this way, molding is performed by repeatedly closing and opening the mold. In the embodiment shown in FIG. 1, the mold consists of two parts and acts as a two-plate type.

Next, an example of use as a three-plate type will be explained with reference to FIG. Among the configurations of this embodiment, the difference in configuration from the embodiment shown in FIG. The only thing that can be done is to release the tightening means that fixes the device to the device.

The fixed side nesting mold 23 has a cavity portion 23a and an injection plunger 2 on the side facing the movable side nesting mold 31.
A recess 23b is formed on the side facing 6a. A communication path 23c communicating with the cavity 23a is formed from the inner bottom surface of the recess 23b. The recess 23b
is formed so that when the fixed mold plate 20 and the runner stripper plate 24 are closed, there is a slight distance between the outer peripheral surface of the injection plunger 26a and the inner wall surface of the recess 23b. This space becomes a runner part during resin molding. In addition, the injection plunger 26a
In order to leave the runner on the runner stripper plate 24 side, a concave groove 26d having a V-shaped cross section is formed on the outer peripheral surface of the tip.

To explain the operation of the mold having the above configuration, after the fixed side mold plate 20 and the movable side mold plate 28 are closed, the nozzle 38 of the injection device touches the nozzle and resin is injected. The injected resin flows through resin path 2.
6b, and is filled into the cavity via the recess 23b.

When opening the mold, first, the space between the runner stripper plate 24 and the stationary mold plate 20 is slightly opened.
At this time, the runner portion is attached to the injection plunger 26a side due to the check effect of the groove 26d.
The molded product and the runner section are cut at the communication path 23c (gate section). Next, the molds are opened between the fixed side nesting mold 23 and the movable side nesting mold 31, and the molded product is attached to the fixed side nesting mold 23. The molded product is released from the mold using ejector pins. Next, remove the runner stripper plate 24 from the fixed side mounting base 26,
Pushing the runner on the side of the runner stripper plate 24 removes the runner from the injection plunger 26a. When closing the mold, the runner stripper plate 24 and fixed side mold plate 20 are advanced to clamp the mold to the fixed side mounting base 26, and the movable side mold plate 28 is advanced to separate the fixed side nesting mold 23 and the movable side mold plate. Match the mold with mold 31. Injection molding is performed repeatedly in this manner. In this way, it can be used as a 3-plate type.

In the embodiment shown in FIG. 2, a groove 2 is provided on the outer circumferential surface of the injection plunger 26a as a check.
6d, but instead of providing the groove 26d,
For example, the outer peripheral surface of the injection plunger 26a is formed into a straight shape, and the runner lock pin 40 is used to connect the fixed side mold plate 20 and the runner stripper plate 20.
When opening the mold, the runner may be locked and left on the runner stripper plate 24 side. An undercut portion is provided on the outer periphery of the tip of the runner lock pin 40, and the tip of the runner lock pin 40 is made to protrude into the recess 23b during resin molding.

In the configurations of the above two-plate type and three-plate type, as described above, only the configuration of the fixed side nesting type differs, and in addition, the fixed side mold plate 20, the runner stripper plate 24, the fixed side mounting base 26,
The movable side template 28 and the like are all used in common.
That is, in the injection molding machine mold of this embodiment, by replacing only the stationary side nesting mold and the movable side nesting mold used in combination with this, a 2-plate type and a 3-plate type can be created. can be converted and used.

Of course, the fixed side template 20 and the movable side template 2
By forming the mold to a standard size according to the size of No. 8, it is easy to replace and use the mold.

In the above embodiment, the recess 22b was provided on the rear surface of the stationary side nesting mold 22, but it is not necessary to form the recess. It is sufficient that at least a communication path connected to the provided resin path 26b is provided.

The above-described mold structure can be applied to various injection molding machines, and can be similarly used not only to an injection device in which the nozzle is touched as in the above example but also to a stationary injection device.

(Effects of the Invention) According to the mold for an injection molding machine of the present invention, since it is configured as described above, it is only necessary to replace the stationary side nesting mold and the movable side nesting mold used in combination therewith. It is possible to convert between a 2-plate type and a 3-plate type with one injection molding machine. Furthermore, by manufacturing the mold to a standard size, the mold can be easily replaced. As a result, it has become possible to select and use the 2-plate type and 3-plate type as appropriate during molding.
The molding machine can be used for a variety of purposes.

[Brief explanation of drawings]

1 and 2 are partial sectional views showing one embodiment of a mold for an injection molding machine according to the present invention, and FIGS. 3 and 4 are partial sectional views showing a conventional example of an injection molding apparatus. 1...Fixed side mold plate, 2...Fixed side nested mold, 5...
...Movable side template, 7...Movable side nesting mold, 8...First
Runner section, 10...Second runner section, 11...
Hot runner part, 20...Fixed side template, 22, 2
3... Fixed side nesting mold, 22a, 23a... Cavity part, 22b, 23b... Recessed part, 22c, 23
c...Communication path, 24...Runner stripper plate, 26...Fixed side mounting base, 26a...Injection plunger, 26b...Resin path, 26c...Nozzle touch portion, 26d...Concave groove, 28... Movable side template,
30...Movable side nesting mold, 36...Injection device.

Claims (1)

[Scope of Claims] 1. A fixed mold including a fixed side mounting base having a resin path for resin injection, a runner stripper plate, a fixed side mold plate loaded with a fixed side nesting mold, and a movable mold mounting. A mold for a three-plate injection molding machine comprising a stand and a movable mold including a movable mold plate into which a movable nesting mold is inserted, wherein the resin outlet of the resin path is from the fixed side mounting base. Provided on the tip surface of an injection plunger that protrudes toward the rear surface of the stationary side nesting mold, and when the mold is closed, the tip of the injection plunger touches the stationary side nesting side of the runner stripper plate. A through hole through which the tip of the injection plunger slides and passes is bored in the runner stripper plate so as to protrude from the surface of the runner stripper plate and the fixed side mounting base. A tightening means is provided for releasably fixing the side mold plate, and the runner stripper plate and the fixed side mold plate are fixed to the fixed side mounting base by the tightening means, and the mold is attached to the two plates. When used as a type, the fixed side nesting mold is connected to the resin outlet of the resin path opened at the tip surface of the injection plunger protruding from the fixed side nesting mold side surface of the runner stripper plate. A mold for an injection molding machine, characterized in that a resin inlet of a communication path communicating with a cavity portion is opened at the rear surface of a fixed-side nested mold. 2. When using the mold as a 3-plate type, it is important to note that a concave groove is formed on the outer peripheral surface of the tip of the injection plunger to prevent the runner from returning, which is formed between the runner stripper plate and the stationary side mold plate. A mold for an injection molding machine according to claim 1.