JPS632198Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention relates to a mold used for sand casting.
In particular, it relates to a mold having a core that is slid horizontally relative to a lower mold and stored in a predetermined position, that is, a slide core.

As is well known, in sand casting, it is necessary to mold a core separately from a lower mold in advance, and then perform a mold matching operation in which the core is placed in a predetermined position with respect to the lower mold. In such mold alignment work, the core and the lower mold are generally aligned using pins and bushes. That is, for example, bushes 3 and 4 are provided at predetermined positions on the lower surface of the cores 1 and 2 shown in FIG. 1, and pins 5 and 6 are provided at corresponding positions on the upper surface of the lower mold 7. Normally, the cores 1 and 2 are aligned with the lower mold 7 by lowering the cores 1 and 2 from above and inserting the bushes 3 and 4 onto the pins 5 and 6.

However, depending on the shape of the mold, it may be impossible to lower the core onto the lower mold from above and align the molds. For example, the core indicated by reference numeral 8 in FIG. 1 has a portion that goes around under another core 2, so it cannot be lowered onto the lower mold 7 from above. Therefore, such a core 8 is usually slid horizontally from the side along the upper surface of the lower mold 7 and stored in a predetermined position. Such a core 8 is generally called a slide core, but in this case, it is not possible to use the pin-and-button method for positioning the core, so as shown in the figure, a predetermined position on the bottom surface of the slide core cannot be used. At the same time, a protrusion (so-called dowel) 9 is formed on the lower mold.
Usually, a recess 10 is formed corresponding to the projection 9 and the recess 10, and the slide core 8 is aligned using these projections 9 and the recess 10. However, in this case, since the protrusions 9 and recesses 10 were formed by processing the sand of the core and lower mold itself, the sand on the surfaces of the protrusions 9 and recesses 10 may be displaced or scraped when the molds are assembled. Furthermore, due to expansion and contraction of the sand and loosening of the mold for mold release, the protrusions 9 and recesses 1
As a result, the positioning of the core cannot be performed accurately, resulting in problems such as variations in product dimensions and defective products. Furthermore, as mentioned above, when the sand is scraped when the core slides, the sand gets caught up in the molten metal when it is poured, resulting in defects in the product.

The purpose of this invention is to effectively solve the above problems by embedding slide rails made of hard material that slidably engage with each other in the opposing surfaces of the slide core and the lower mold. Then, by using this slide rail to slide the slide core to a predetermined position, the core is accurately positioned,
This prevents the sand in the core and lower mold from being scraped, thereby improving the dimensional accuracy of the product and at the same time preventing the occurrence of defects due to sand entrainment.

Hereinafter, embodiments of this invention will be described in detail with reference to FIGS. 2 to 7.

FIG. 2 shows an example of the slide core 11 used in the mold of this invention, and FIG. 3 shows an example of the core mold 12 for molding the slide core 11. This core mold 12 is composed of a core upper mold 13 and a core lower mold 14, and a convex slide rail 15 to be embedded in the slide core 11 is provided at a predetermined position of the core lower mold 14. A recessed set rail 16 is provided in advance for setting. If such a core mold 12 is used, the convex slide rail 15 is set on the concave set rail 16, and molding sand is filled and hardened in this state,
As shown in FIG. 2, a slide core 11 is obtained in which a convex slide rail 15 is embedded in a predetermined position on the lower surface side. The convex slide rail 15 is embedded so that its protruding portion 15A protrudes from the lower surface of the slide core 11.

FIG. 4 shows a lower mold 17 used in combination with the slide core 11 described above, and FIG. 5 shows an outer lower mold 18 for molding the lower mold 17. This outer lower mold 18 is placed on a molding frame 2 on the lower mold 19.
A convex set rail 22 is provided on the upper surface of the lower mold 19 for setting the recessed slide rail 21 to be placed and buried in the lower mold 17. Using such an outer and lower mold 18, by setting the concave slide rail 21 on the convex set rail 22 and filling and hardening molding sand into the molding frame 20, a concave mold is formed as shown in FIG. A lower mold 17 in which the slide rail 21 is embedded is obtained. Note that this concave slide rail 21 has a concave groove portion 21A.
is embedded so as to be exposed on the surface of the lower mold 17.

In the above description, the convex slide rail 15 of the slide core 11 and the concave slide rail 21 of the lower mold 17 are defined by the protrusion 15A and the concave groove 21.
15A of the convex slide rail 15.
The structure is such that the slide core 11 can be slid with respect to the lower mold 17 while being engaged with the concave groove portion 21A of the concave slide rail 21. Note that these convex slide rails 15 and concave slide rails 21 are provided in two or more parallel stripes as shown in the figure in order to ensure the stability of the slide core 11 when it slides. This is desirable. Furthermore, the convex slide rail 15 and the concave slide rail 21 are made of a hard material such as metal or heat-resistant hard resin.

FIG. 6 and FIG. 7 show the above-mentioned slide core 1.
An example of a mold of this invention using a mold 1 and a lower mold 17 is shown. During mold matching work of such molds, the convex slide rail 1 of the slide core 11
5 is engaged with the concave groove part 21A of the concave slide rail 21 of the lower mold 17, and in this state, slide the slide core 11 horizontally from the side to place the slide core 11 in a predetermined position. You can move it to. Here, since the convex slide rail 15 and concave slide rail 21 made of hard materials are extremely unlikely to undergo dimensional changes or positional deviations, the convex slide rail 15 and concave slide rail 21 are used during sliding. By aligning the molds by sliding the core 11, the position of the slide core 11 can be set extremely accurately. The final positioning of the slide core 11 is performed, for example, by using the groove 2 of the slide rail 21 as shown in FIG.
A stopper surface 22 is formed at the end of 1A,
Convex slide rail 15 on this stopper surface 22
This can be done by bringing the tips of the protrusions 15A into contact with each other. And also convex slide rail 1
The height of the protruding portion 15A of No. 5 or the depth of the concave groove portion 21A of the concave slide rail 21 is set such that there is a slight gap between the lower surface of the slide core 11 and the upper surface of the lower mold 17, as shown in FIG. It is desirable to set the slide core so that 23 is generated. In this way, the slide core 11 and the lower mold 17 do not come into direct contact with each other when the slide core 11 slides, so that the sand on their surfaces is not scraped. Therefore, it is effectively possible to prevent sand scraped during sliding from being caught in the product and causing defects.

In addition, in the above-mentioned embodiment, the slide core 11
Although the convex slide rail 15 is buried in the lower mold 17 and the concave slide rail 21 is buried in the lower mold 17, conversely, the concave slide rail 21 is buried in the slide core 11 and the convex slide rail 15 is buried in the lower mold 17. Of course, it is also possible to have a configuration in which the Also slide core 11
The slide rails buried in the mutually opposing surfaces of the lower mold 17 are not necessarily limited to convex and concave shapes, but may have any shape as long as they can slidably engage with each other.

As is clear from the above explanation, the mold of this invention is equipped with slide rails made of hard material on the opposing sides of the lower mold and the slide core, and therefore, during mold alignment work, Since the slide core can be positioned extremely accurately by using the slide rail, a remarkable effect can be obtained in which the dimensional accuracy of the product can be significantly improved compared to the conventional method. In particular, according to an embodiment in which a gap is formed between the lower mold and the slide core by the slide rail, the sand is not scraped when the slide core slides, so the product is produced by entrainment of sand. This has the effect that defects are less likely to occur.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional view showing an example of a mold using a conventional sliding core, Fig. 2 is a longitudinal sectional view showing an example of a sliding core used in the mold of this invention, and Fig. 3 is a longitudinal sectional view showing an example of a mold using a conventional sliding core. FIG. 4 is a longitudinal sectional view showing a core mold for molding the sliding core shown in FIG. 4; FIG. 4 is a longitudinal sectional view of a lower mold used in combination with the sliding core shown in FIG. The figure is a longitudinal sectional view of the outer lower mold for producing the lower mold shown in Figure 4, and Figure 6 is a mold of this invention which is a combination of the slide core shown in Figure 2 and the lower mold shown in Figure 4. A vertical sectional view showing an example, FIG. 7 is a sectional view taken along the - line in FIG. 6. 11...Slide core, 15...Convex slide rail, 17...Lower mold, 21...Concave slide rail, 23...Between.

Claims (1)

[Claims for Utility Model Registration] (1) In a mold having a sliding core that is slid horizontally relative to a lower mold and stored in a predetermined position, surfaces of the lower mold and the sliding core that face each other; A mold characterized in that slide rails made of a hard material are embedded in each of the slide rails that are slidably engaged with each other. (2) The mold according to claim 1, wherein the slide rail is configured to create a gap between the opposing surfaces of the lower mold and the slide core.