JPH063139A - Dimensional inspection method of internal surface of molding die - Google Patents

Abstract

PURPOSE:To obtain a method which enables dimensional inspection of the internal surface of a die easily and without damaging the internal surface thereof with handy equipment. CONSTITUTION:A soft foam body with a thickness than a space between internal furnaces 17 and 19 of a molding die 10 is impregnated with a hardening type resin to form a resin impregnated foam body 15, which 5 is arranged into the molding die 10. The molding die 10 is closed and the resin impregnated foam body 15 is compressed with internal surfaces 17 and 19 of the molding die to be given a shape of the internal surfaces of the die while the resin in the resin impregnated foam body 15 is hardened to form a foam product. Thereafter, the foam product is take out of the molding die 10 and dimensions of parts of the foam product are measured to inspect the dimensions of the internal surfaces of the molding die.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for inspecting the dimensions of the inner surface of a mold during or after the manufacture of the mold.
Here, the dimension means not only the length, the thickness, and the interval, but also the surface shape such as a curved surface shape and a bent shape.

[0002]

2. Description of the Related Art In automobile interior products such as automobile molding ceilings and automobile door panels, or other panel-shaped resin products, a molding material is molded using a molding die having a mold inner surface having the same shape as the outer surface of the product. Compression molding or foam molding is performed on the inner surface shape.

By the way, in the above-mentioned forming die, since the outer shape of the product is determined by the inner surface of the die, it is necessary to finish the inner surface of the die accurately. Therefore, the dimensions of the inner surface of the molding die are inspected during or after the manufacturing of the molding die.

Conventionally, as a dimension inspection method for the inner surface of the molding die,
Instead of directly measuring the dimensions of the inner surface of the mold, insert a lead plate, lead rod or clay between the inner surfaces of the mold to shape the inner surface of the mold, or inject silicon rubber into the mold to harden it to the inner surface of the mold.
After that, take out the lead plate from the forming die and measure the dimensions of each part of the lead plate, etc., to easily inspect the dimensions of the inner surface of the die, or to mount the die on a regular process and equipment and at the same time. It is performed to inspect a product manufactured by using a raw material and under almost the same conditions as a normal production process.

[0005]

However, the above dimension inspection method has the following problems. First, when a lead plate or a lead rod is used, since the density of lead itself is high, the lead plate and the lead rod become extremely heavy and the handling becomes difficult when the inner surface of the mold to be inspected becomes large. In addition, since lead plates and lead rods do not deform to the inner shape of the mold unless the mold clamping pressure is increased, not only a large mold clamping device is required, but especially when the mold is made of aluminum There is also a problem that scratches due to the scratches easily occur on the inner surface of the mold.

On the other hand, in the case of clay, there is a problem that the clay is easily damaged when it is placed on the inner surface of the mold, when it is taken out from the molding die, and when the dimension is measured, and it is not easy to handle. Further, there is a problem that the dimension measurement of silicon rubber is not easy because it is easily deformed when taken out from the molding die, and moreover, the dimension measurement is not possible because it is expensive.
Therefore, in some cases, the mold is mounted on the regular process and equipment as described above and is often prototyped. However, in this case, there is a problem that the loss becomes large, such as the preheating of the mold and the auxiliary device, the preparation such as the preparation of the material, and the post-treatment are indispensable.

Therefore, in view of the above points, the present invention provides a method capable of easily performing a dimensional inspection of the inner surface of a mold with simple equipment and without damaging the inner surface of the mold.

[0008]

According to the present invention, a resin-impregnated foam is formed by impregnating a curable resin into a soft foam having a thickness larger than the distance between the inner surfaces of a molding die to form a resin-impregnated foam. The resin-impregnated foam is placed in a mold, the resin-impregnated foam is closed on the inner surface of the mold to shape the inner surface of the mold, and the impregnated resin in the resin-impregnated foam is cured to form a cured product of the foam. The present invention relates to a method for inspecting a dimension of an inner surface of a molding die, which comprises forming and thereafter taking out the cured foam material from a molding die and measuring a dimension of each portion of the cured foam material.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings. 1 to 5 are sectional views showing an embodiment of the present invention in the order of work. First, the resin-impregnated foam 15 is formed by impregnating the curable resin 14 into the soft foam 12 having a thickness larger than the inner surface of the molding die 10.

The molding die 10 in this embodiment is an upper die 1.
6 and lower mold 18, inside of product shape mold space 2
Has 0. The mold inner space 20 is composed of an upper mold inner surface 17 and a lower mold inner surface 19. The mold 10 may be in the middle of manufacturing or at the end of manufacturing.

The soft foam 12 may be mainly composed of an open cell structure that can be impregnated with the curable resin 14, and a soft urethane foam slab is particularly preferable. The thickness of the soft foam 12 differs depending on the hardness of the soft foam used, the shape of the inner surface of the mold, etc.
It is preferable that the distance between 7 and 19 is about 120%. The soft foam 12 may have multiple layers. Also,
The size of the soft foam 12 is made larger than the portion to be inspected on the inner surface of the mold. For example, when inspecting the dimension of the entire die inner surface, it is made larger than the entire die inner surface, while when inspecting the dimension of a part of the die inner surface, it is made larger than the inspected portion.

As the curable resin 14, a liquid resin having a viscosity capable of impregnating the soft foam 12 is used. As the curable resin 14, an epoxy resin or a water-curable isocyanate compound solution is used. The impregnation amount of the curable resin 14 differs depending on the type of the curable resin 14 and the like.
It is preferably 200 to 600 g per liter volume. As an example of an epoxy resin, a curing agent H-18 (manufactured by SKAKEN) 18 against L-404 (manufactured by SKAKEN) is used.
g, and the curing time is set to 24 hours.

The curable resin 14 is impregnated with
It is carried out by a usual impregnation method such as brush coating or dipping. Further, in order to make the impregnation amount constant, it is preferable to pass the soft foam after impregnation between the rolls and squeeze the soft foam to a predetermined thickness.

Next, as shown in FIG. 2, the resin-impregnated foam 15 is placed in the molding die 10. Of course, when inspecting the dimensions of a part of the inner surface of the mold, the resin-impregnated foam 15 may be placed on the inner surface of the mold to be inspected.

The resin-impregnated foam 15 is molded into the mold 1.
It is preferable that a mold release agent is applied to the mold inner surfaces 17 and 19 or a mold release sheet is arranged prior to the arrangement in the mold 0. In addition, a net-like reinforcing sheet made of cotton cloth or the like may be laminated in one layer or two or more layers on the resin-impregnated foam body 15, or when the resin-impregnated foam body 15 is composed of multiple layers, it may be sandwiched between the resin-impregnated foam bodies 15. When the reinforcing sheet is also used, the strength of the cured product of the foam formed by curing the impregnated resin can be increased, and the cured product of the foam can be more easily handled during demolding or dimension measurement.

Thereafter, as shown in FIG. 3, the upper mold 16 and the lower mold 18 of the mold 10 are closed, and the resin-impregnated foam 15 is compressed by the mold inner surfaces 17 and 19 to be shaped into the mold inner surface.
The mold clamping pressure at this time may be small because the resin-impregnated foam 15 in the mold uses the soft foam 12 as a constituent material. Then, the curable resin in the resin-impregnated foam 15 is left to stand for a predetermined time in the closed state to cure. As a result, the resin-impregnated foam 15 becomes a foam-cured product 22 fixed in the same shape as the inner surface of the mold. When the impregnating resin is a resin that generates heat during curing, such as an epoxy resin, the cured product 22 of the foam has little distortion and high dimensional stability.
In order to obtain the temperature, the temperature of the mold 10 at the time of curing is 40 ° C.
It is preferable to keep below.

After the impregnated resin is cured, the mold 10 is opened to remove the foamed cured product 22, as shown in FIG. Then, as shown in FIG. 5, the thickness, length, curved surface shape and other dimensions of each portion of the cured product 22 of the foam are measured by a measuring tool 24 such as a caliper, a micrometer, and an R gauge, and the measured values are used to measure the inner surface 17 of the mold. , 19 are examined to see if they are accurate. At that time, a visual inspection is appropriately added.

[0018]

As shown and described above, according to the present invention, since the resin-impregnated foam formed by impregnating the flexible foam with the curable resin is compressed on the inner surface of the mold, the clamping pressure is small. You can easily inspect the dimensions of the inner surface of the mold with simple equipment. Moreover, since the soft soft foam is compressed on the inner surface of the mold, the inner surface of the mold is not damaged. In addition, the soft foam is lightweight and easy to handle, and in addition,
Since it is much cheaper than silicon rubber or the like, the dimensional inspection of the inner surface of the mold can be performed easily and inexpensively.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an impregnation of a curable resin according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a process of placing a resin-impregnated foam in a mold in the same example.

FIG. 3 is a cross-sectional view showing a state where the resin-impregnated foam is compressed on the inner surface of the mold in the example.

FIG. 4 is a cross-sectional view showing a case where a cured product of a foam is released from a mold in the same example.

FIG. 5 is a cross-sectional view showing a dimension of a cured product of foam in the same example.

[Explanation of symbols]

 10 Mold 12 Soft Foam 14 Curable Resin 15 Resin Impregnated Foam 17 Mold Inner Surface 19 Mold Inner Surface 20 Mold Inner Space 22 Foam Cured Product

Claims (1)

[Claims] 1. A resin-impregnated foam is formed by impregnating a curable resin into a soft foam having a thickness greater than the distance between the inner surfaces of the molding die to form a resin-impregnated foam, and arranging the resin-impregnated foam in the molding die. The mold is closed and the resin-impregnated foam is compressed on the inner surface of the mold to shape the inner surface of the mold, and the impregnated resin in the resin-impregnated foam is cured to form a cured product of the foam, and then the foam is cured. A method for inspecting a dimension of an inner surface of a molding die, which comprises taking out a product from a molding die and measuring a dimension of each part of the cured product of the foam.