JPH0110188Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a mold having a dynamic positioning structure between a cavity and a core.

[Prior art and its problems] The parallelism when the die plate of the molding machine is closed is
The clearance between the mold guide pin and guide bush is approximately 0.05 to 0.2 mm, and the clearance between the mold guide pin and guide bush is approximately 0.01 to 0.05 mm, so when the mold is set on the die plate and the molding machine is operated, the fixed side and movable side of the mold are separated. A positional deviation of about 0.05 mm occurs, making it difficult to ensure the positional relationship even if the mold product part is manufactured with high precision. For this reason, taper pins and the like have been embedded in the cavity plate and the core plate in order to accurately maintain the positional relationship between the cavity and the core during molding.

FIG. 3 shows an example of a conventional mold.

1 is a cavity plate fixed to a fixed die plate of a molding machine, 2 is a cavity fixed to the cavity plate 1 and has a mold engraving part 2a and a receiving part 2b for a nesting pin, and 3 is a cavity plate fixed to the cavity plate 1. It is a fixed taper bush. Also,
4 is a core plate fixed to a movable die plate of a molding machine, 5 is a core having a mold engraving portion 5a fixed to the core plate 4, 6 is a nesting pin,
7 is a taper bush 3 fixed to the core plate
It is a core pin that fits into the

The cavity plate 1 and the core plate 4 are positioned and connected to each other by a guide pin and a guide bush (not shown). The right half of the figure shows the state in which the core plate 4 is separated from the cavity plate 1 before the mold is closed, and the left half shows the state in which the core plate 4 is moved and the mold is closed.

In such a conventional mold, when the mold is closed, the taper pin 7 fits into the taper bush 3, thereby accurately positioning the cavity 2 and the core 5.

However, when the insert pin 6 of the core 5 jumps into the cavity 2, the insert pin 6 may forcefully jump into the cavity 2 and then be positioned by the taper pin 7 due to the misalignment between the cavity plate 1 and the core plate 4. In such a case, there were problems such as breakage of the nesting pin 6 and sagging of the receiving portion 2b.

In addition, when the cavity 2 and the core 5 have tapered pressed surfaces 2c and 5b as shown in the figure, when the mold is closed, the tapered pressed surfaces 2c and 5b always come into contact with each other and are then positioned by the taper pin 7. In addition, galling occurred on the tapered pressed surfaces 2c and 5b, causing burrs to appear on the molded product.

[Purpose of the invention] The purpose of the invention is to propose a mold that performs accurate positioning before the mold is closed, and eliminates damage to the nesting pin and generation of burrs due to galling of the tapered extrusion surface. It is in.

[Summary of the invention] The present invention is a mold that has a cavity plate and a core plate, and also has a taper bush and a taper pin that fit into the cavity plate and the core plate to position each other. A molding die in which a taper pin or a taper bush is provided on a cavity plate or a core plate so as to protrude from the cavity plate or a core plate, and the taper pin and taper bush fit together to perform accurate positioning before the mold is closed. It is.

[Embodiments of the invention] Hereinafter, the invention will be described in detail using drawings showing preferred embodiments.

1 and 2 are cross-sectional views of molds according to a first embodiment and a second embodiment of the present invention, respectively.
In the figure, parts given the same reference numerals as those in FIG. 3 have the same configuration as in FIG. 3, and therefore explanations thereof will be omitted.

In the first embodiment shown in FIG. 1, a taper bush 3' is provided on the core plate 4 side. 1
0 is a taper pin slidably inserted into a hole 1a provided in the cavity plate. The fitting clearance between the taper pin 10 and the hole 1a is extremely small. A flange portion 10a is formed at the rear end of the taper pin 10.
a is located in a cavity 1b that is continuous with the hole 1a of the cavity plate 1, and prevents the taper pin 10 from falling out of the hole 1a. Further, the taper pin 10 can be made to protrude in the direction of the hole 1a by the depth of the cavity 1b. 11 is the hollow part 1b
is a compression spring housed between the end face of the taper pin 10 and the flange portion 10a of the taper pin 10, and is always connected to the taper pin 10.
is urged in the direction of pushing out from the hole 1a.

From the above configuration, even when the core plate 4 is separated from the cavity plate 1 as shown in the right half of FIG. 1, the taper pin 10 is pushed out from the cavity plate 1 by the compression spring 11, and the mold is closed. Having previously been fitted into the taper bush 3' of the core plate 4, the cavity plate 1 and the core plate 4 are positioned relative to each other.

When the mold is then closed, the taper pin 10 is pushed into the hole 1a while being fitted into the taper bush 3'. In addition, as the nesting pin 6 jumps into the receiving part 2b, the taper press face 2c of the cavity 2 and the core 5
The tapered pressing surface 5b is pressed and mold closing is completed. At this time, the cavity plate 1 and the core plate 4 are positioned in advance by the taper pin 10 and the taper bush 3' as described above, so that the nesting pin 6 does not forcefully jump into the receiving part 2b.
Furthermore, galling does not occur between the tapered pressed surfaces 2c and 5b. Therefore, damage to the nesting pin 6 and generation of burrs on the molded product are prevented.

Next, a second embodiment shown in FIG. 2 will be explained.

In the molding die of the second embodiment, the taper pin 13 is divided and fixed in contact with the peripheral wall 5c of the core 5 as shown in the figure, and the taper bush 12, which is fitted with the similarly divided taper pin 13, is attached to the cavity 2. It is slidably inserted into the gap 1c formed between the peripheral wall 2d and the cavity plate 1,
In addition, a spring 14 is provided that biases the taper bush 12 in a direction to push it out. Moreover, a flange portion 12b is formed on the taper bush 12 to prevent it from falling off.

With this configuration, in the second embodiment, as in the first embodiment, the taper bush 12 pushed out by the spring 14 fits into the taper pin 13 as shown in the right half of FIG. 2 before the mold is closed. As a result, accurate positioning is performed first and then the mold is closed, thereby preventing damage to the nesting pin 6 and occurrence of burrs on the molded product.

In addition, in the second embodiment, the taper bush 1
2 and the tapered pressed surfaces 12a, 13 of the taper pin 13
By making the angle a steeper than the angle between the tapered press surfaces 2c and 5b of the cavity 2 and the core 5, positioning can be performed more reliably and good results can be obtained.

In addition, although the above explanation shows the case where the taper pin or taper bush is provided so as to protrude freely from the cavity plate, it is of course possible to provide the taper pin or taper bush from the core plate side so that it can protrude freely, and the same result can be obtained in this case as well. It will be done. Furthermore, although the pressure means using a compression spring is shown in order to make the taper pin or taper bush slidable by a predetermined amount, pressure means such as hydraulic pressure or pneumatic pressure may be used instead.

[Effects of the invention] As described above, according to the invention, a taper pin or taper bush is protrusively provided on either the cavity plate or the core plate, and accurate positioning is performed before the mold is closed. This prevents damage to the molded product and also prevents burrs from forming on the molded product. Therefore, it is extremely practical for improving the durability of the mold and improving the molding accuracy.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a mold according to a first embodiment of the present invention, Fig. 2 is a sectional view of a mold according to a second embodiment of the present invention, and Fig. 3 is a sectional view of a conventional mold. It is a sectional view showing an example. Here, 1... cavity plate, 2... cavity, 3', 12... taper bush, 4...
... Core plate, 5 ... Core, 6 ... Nesting pin,
10, 13... Taper pin, 11, 14... Compression spring.

Claims (1)

[Claims for Utility Model Registration] (1) A mold that has a cavity plate that fixes a cavity and a core plate that fixes a core, and that is provided with a taper pin and a taper bush that fit into the cavity plate and the core plate. In the mold, at least either the taper pin or the taper bush is provided so as to protrude from the cavity plate or the core plate, and the taper pin and the taper bush are fitted together before closing the mold to position the cavity and the core. mold. (2) The mold according to claim 1 of the utility model registration claim, characterized in that at least either the taper pin or the taper bush is biased by a compression spring and positioned so as to protrude from the cavity plate or the core plate. .