JPH043709Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a core for casting cylinder blocks.

[Prior art]

Conventional cores for cylinder block casting include:
For example, there are those shown in FIGS. 4 and 5. 11
For example, this is the main body of a core used in a mold for casting a cylinder block for a V-type engine. 12 is a baseboard for positioning formed at the bottom of this core body 11, and 12a serves as its reference surface. This allows the core body 11 to be accurately held in position when assembled into a main mold (not shown), thereby producing a cylinder block with good dimensional accuracy.

[Problems to be solved by the invention] However, in the case of such conventional cylinder block casting cores, there is a positioning width that has the function of holding the core body at a predetermined position within the casting space of the main mold. Since the wood was naturally formed to protrude the most from the core body, when handling the core, the baseboard positioning reference surface 12a is directly placed on the floor or conveying device.
comes into contact. For example, during transportation, the core may slide sideways on the conveyor and change direction.
Frequently, the reference surface 12a of the baseboard 12 becomes severely worn (indicated by the dashed line 12a' in FIG. 6). FIG. 6 shows a phenomenon caused by the wear of the positioning skirting board. The core body 11, which should originally be positioned at the position shown by the solid line 15 of the main mold 14, is not aligned with the baseboard reference plane 12a. Depending on the wear, the position will shift as shown by the chain line 16. In the case of vertical parting type casting, it may fall as shown by the solid line 17.

In any case, it is not possible to obtain a cast product with good dimensional accuracy using such a core. Particularly in the case of cylinder blocks for V-type engines that require precise balance, even a slight deviation of the core can have a serious impact on product quality.

This invention was devised in view of these conventional problems, and aims to provide a core for cylinder block casting which prevents wear from occurring on the reference surface of the positioning baseboard.

[Means for solving problems]

This invention, which achieves the above object, is a core that is incorporated into a mold for casting a cylinder block.
On the core positioning baseboard, positioning reference surface protection parts that can be fitted loosely into the plurality of protection part receiving grooves carved on the core support reference surface of the main mold are installed locally from the baseboard positioning reference surface. This is a core for casting cylinder blocks that is integrally protruded from and attached to the cylinder block.

〔Example〕

This invention will be explained below based on the drawings.

1 to 3 are diagrams showing an embodiment of this invention. Skirting board 2 for positioning the core body 1 for cylinder block casting incorporated in the main mold 4 (for example, frameless casting having a vertical parting surface 4a)
A positioning reference protection section (hereinafter referred to as "surface protection section") 3 is also provided. As shown in FIG. 3, the surface protection portion 3 of this embodiment includes a plurality of protection portion receiving grooves 4b carved in the core support reference surface 4c of the main mold 4.
It can be fitted loosely into each of the baseboards 2 and protrudes from two locations on the reference surface 2a of the positioning baseboard 2. There is no need to specifically limit the number, shape, dimensions, etc., and the point is that when the core body 1 is assembled into the main mold 4, the reference surface 2a of the baseboard 2 for positioning is aligned with the reference surface 4c for supporting the core.
Furthermore, when the core body 1 is placed on the floor, the core body 1 can be stably supported, and the wear due to friction with the floor and the receiving groove 4c can be avoided. It is sufficient if the depth of the area is taken into account. Moreover, regarding its formation, it is integrally molded in the core molding process, and can be easily formed by, for example, a shell molding method.

Next, the action will be explained.

Even if the core body 1 is slid sideways during transportation, for example, it is the sliding surface 3a of the protruding surface protection portion 3 that wears out, and the reference surface 2a of the positioning baseboard 2 does not wear out. Even if wear occurs on the surface protection part 3, as shown in FIG. Since the reference surface 2a of the wood 2 is placed in contact with the core support reference surface 4c, accurate positioning is possible, so that a highly accurate cylinder block for a V-type engine can be manufactured.

[Effect of idea]

As explained above, according to this idea,
A simple method is to install a surface protection part on the baseboard for positioning, which can be loosely fitted into the protection part receiving groove carved in the reference surface for supporting the core of the main mold, and protrudes locally from the baseboard positioning reference surface. The structure prevents wear that occurs during handling of the core body only to the surface protection part, and makes it possible to place the reference surface of the positioning skirting board in contact with the core support reference surface. Since the child is correctly set at a predetermined position within the casting space of the main mold, a remarkable effect is obtained in that high precision of the product can be guaranteed. In addition, since the core of this invention has a surface protection part integrally formed, there is no need to attach or remove a separate member for protecting the positioning reference surface after manufacturing the core, and the transfer device is It's fine to use one.

[Brief explanation of the drawing]

Fig. 1 is a front view of an embodiment of this invention, Fig. 2 is a side view thereof, Fig. 3 is a front view illustrating its operation, and Figs. 4 and 5 are of a conventional cylinder block casting core. One example is shown, and FIG. 4 is a front view, FIG. 5 is a side view, and FIG. 6 is a front view for explaining a defective phenomenon. 1... Core for cylinder block casting (main body),
2... Skirting board for positioning, 4... Main mold, 3... Positioning reference surface protection part, 2a... Baseboard positioning reference surface, 4b... Protective part receiving groove, 4c... Core support reference surface.

Claims (1)

[Scope of utility model registration request] A core to be incorporated into a mold for casting a thin double block, and a positioning reference that can be fitted loosely into a plurality of protection grooves carved into a core support reference surface of the main mold on a baseboard for positioning the core. A core for casting a cylinder block, characterized in that a surface protection portion is provided by protruding locally and integrally from a baseboard positioning reference surface.