JP3219808B2 - Method of adjusting mold parallelism in injection molding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for adjusting the parallelism of a mold plate in an injection molding machine.

[0002]

2. Description of the Related Art Conventionally, this type of mold plate parallelism adjustment method has
A mold is attached to a fixed platen and a movable platen which constitute a mold clamping device of an injection molding machine, and a mold clamping force is applied to the mold at an ordinary temperature so that no gap between the mold plates is eliminated. Measurement was performed, and the position of the tie bar and the like were adjusted to adjust the mold parallelism.

[0003]

Generally, during injection molding, the temperature of a mold is several steps higher than room temperature.

However, in the above-described conventional method, the mold parallelism is measured by applying a mold clamping force at room temperature and smaller than the mold clamping force at the time of molding so as to eliminate the gap between the molds. Therefore, it is not possible to cope with variations in the thickness in the mold clamping direction due to the thermal expansion of the mold that has been heated to a high temperature generated during injection molding. That is, due to the thermal expansion of the mold, a deviation occurs between the parallelism of the mold plate at the time of injection molding and the parallelism of the mold plate adjusted at the normal temperature, and the uniform mold clamping force is not applied to the mold. There is a problem that the size of the product is adversely affected.

The present invention has been made in view of the above-mentioned problems of the prior art, and makes it possible to apply a uniform mold clamping force to a high-temperature mold during injection molding. It is an object of the present invention to realize a method of adjusting a mold plate parallelism in an injection molding machine.

[0006]

In order to achieve the above object, a method of adjusting the parallelism of a mold plate in an injection molding machine according to the present invention comprises attaching a mold to a fixed plate and a movable plate of a mold clamping device of the injection molding machine. After the temperature of the mold is adjusted to the temperature at the time of molding and stabilized at the temperature at the time of molding, at least the fixed platen and the movable platen are fixed to the mold with the mold clamping force applied at the time of molding. The parallelism adjusting means provided on one side adjusts the mold parallelism of the mold so as to fall within a predetermined allowable value.

The mold plate parallelism may be obtained by measuring the distance between the fixed platen and the movable platen at several places, and as a dimensional difference between the distances at the several places.

[0008]

[Function] The mold is thermally expanded at the temperature at the time of injection molding, and the mold plate parallelism is adjusted while applying the same mold clamping force as at the time of injection molding. It can be adjusted to the board parallelism.

[0009]

An embodiment of the present invention will be described with reference to the drawings.

FIGS. 1A and 1B show a first embodiment, wherein FIG. 1A is a schematic front view of a main part thereof, and FIG. 1B is a schematic side view of the same seen from a fixed platen side.

First, an example of a mold clamping device used for carrying out the present invention will be described.

A fixed platen 3 on which the fixed mold 1 is mounted is fixed to the center of the bed 8, and a mold clamping housing (not shown) is fixed to one end of the bed 8. The fixed platen 3 and the mold clamping housing are connected by four tie bars 5, and a movable platen between which the movable mold 2 guided by the tie bar 5 and reciprocally movable in the axial direction is mounted. 4 are provided. The movable platen 4 is provided with a ram 4a of a mold clamping force generating mechanism provided in the mold clamping housing.
Is reciprocated.

A pipe 7a of a temperature controller 7 communicates with a mold composed of a fixed mold 1 and a movable mold 2 attached to the fixed plate 3 and the movable plate 4 of the mold clamping device, respectively.
The mold is configured to be able to control the temperature to a predetermined temperature.

Next, the steps of the first embodiment will be described.

A fixed die 1 and a movable die 2 are mounted on a fixed platen 3 and a movable platen 4 of the mold clamping device, respectively. Then
The temperature of the mold including the fixed mold 1 and the movable mold 2 is adjusted by a temperature controller 7 to a temperature at the time of injection molding. After the temperature is stabilized, the mold clamping force having the same size as that at the time of injection molding is obtained. And mold clamping is performed.

Thereafter, the distance between the fixed platen 1 and the movable platen 2 is measured by, for example, an inside gauge, a laser measuring device, or the like at four portions near the four tie bars 5.

Then, a value obtained by subtracting the minimum value from the maximum value among the distances of the four portions measured as described above is defined as the mold plate parallelism, and the mold plate parallelism falls within a predetermined allowable value. As described above, the parallelism of the mold plate is adjusted by changing the thickness of the shims 6 arranged at the four corners of the fixed mold 1 between the fixed mold 1 and the fixed platen 2.

FIG. 2 is a partial sectional front view showing a main part of the second embodiment.

In this embodiment, the parallelism of the mold plate is adjusted by adjusting the protrusion length of the adjusting screw 16 screwed into the screw hole of the fixed plate 13 instead of the shim 6 of the first embodiment. It is. The other parts are the same as in the first embodiment, and a description thereof will be omitted.

FIG. 3 is a front view showing a main part of the third embodiment.

In this embodiment, the parallelism of the mold plate is adjusted by wedges 26 instead of the shim 6 of the first embodiment. The other parts are the same as in the first embodiment, and a description thereof will be omitted.

In each of the above embodiments, the mold plate parallelism is adjusted between the fixed platen and the fixed mold. However, the present invention is not limited to this.
The above-described mold parallelism adjusting means may be provided between the movable mold and the movable mold to adjust the mold parallelism between the movable mold and the movable mold. Alternatively, mold parallelism adjusting means may be provided for both the fixed mold and the fixed board, and both the movable mold and the movable board, and the mold parallelism may be adjusted by both.

[0023]

Since the present invention is configured as described above, it has the following effects.

Since the mold plate parallelism is adjusted at the temperature of the mold during injection molding and with the same mold clamping force applied during injection molding, the mold due to the thermal expansion of the mold as in the conventional example is used. There is no shift in the parallelism of the mold plate due to variations in the thickness in the clamping direction, and a uniform clamping force can be applied to the mold, so that the dimensions of the molded product are high. In particular, it is effective when used for injection compression molding that requires precision of the mold parallelism.

[Brief description of the drawings]

FIGS. 1A and 1B show a main part of a mold clamping apparatus used for carrying out a first embodiment, wherein FIG. 1A is a schematic partial front view and FIG. 1B is a schematic side view.

FIG. 2 is a schematic partial front view showing a main part of a mold clamping device used for carrying out a second embodiment.

FIG. 3 is a schematic partial front view showing a main part of a mold clamping device used for implementing a third embodiment.

[Explanation of symbols]

 1,11,21 Fixed mold 2 Movable mold 3,13,23 Fixed plate 4 Movable plate 5 Tie bar 6 Shim 7 Temperature controller 8 Bed 16 Adjustment screw 26 Wedge

Claims (2)

(57) [Claims] 1. A mold is mounted on a fixed platen and a movable platen of a mold clamping device of an injection molding machine, and the temperature of the mold is adjusted to a temperature at the time of molding and stabilized at the temperature at the time of molding. When the mold clamping force is applied to the mold, the parallelism adjusting means provided on at least one of the fixed board and the movable board allows the mold parallelism of the mold to fall within a predetermined allowable value. Adjustment method for an injection molding machine. 2. The injection molding according to claim 1, wherein the mold plate parallelism is obtained by measuring a distance between the fixed platen and the movable platen at several places, and as a dimensional difference of the distances at the several places. Method of adjusting the parallelism of the mold plate in the machine.