JPS5835788B2 - Front lid of centrifugal casting mold - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a front cover disposed at one end of a centrifugal casting mold to mold the inner periphery of one end of a product.

As shown in FIG. 1, the front cover 1 includes a support metal fitting 2 that is fitted onto the inner periphery of one end of the rotary metal frame 5 and fixed with a taper pin 4, etc., and is supported by being fitted externally to the support metal fitting 2. and a sand mold core 3 for forming the inner periphery of one end of the cast product.

This front cover 1 has conventionally been created by directly molding the core 3 onto the support hardware 2, so there is no gap between the support hardware 2 and the core 3, and the molten metal solidifies and shrinks after casting, causing the product to shrink on cooling. On the other hand, the core 3 is compressed due to the thermal expansion of the support hardware 2, and together with the fact that the support hardware 2 and the core 3 are firmly attached, the removal work of the support hardware 2 after casting is completed is significantly hindered. It had been.

Therefore, a method has been adopted in which the core 3 is fitted into the support hardware 2, but in order to fix the support hardware 2 and the core 3, for example, as shown in FIGS. 2 and 3, An engaging groove 6 is formed on the inner circumferential surface of the child, and a protrusion 7 is provided on the supporting hardware 2 to fit into the engaging groove for engagement and fixation.
As disclosed in No. 141327, a protrusion is provided on the inner periphery of the core 3, into which the protrusion of the support metal fitting 2 is bitten, but it is difficult to securely fix it, and this is difficult for large-diameter products. was particularly problematic.

That is, if the fixation is not reliable, there is a problem that the core may be pulled out during transportation of the front cover, or the core may rotate or shake during casting rotation, resulting in damage to the core.

The present invention has been made in view of these problems, and includes a front cover that allows easy removal of the supporting hardware after completion of casting, easy attachment of the core to the supporting hardware, and reliably prevents breakage of the core. For the purpose of providing.

In order to achieve this object, the present invention is based on a method in which a core is fitted into a supporting hardware, and a seven-rung portion protruding from the outer periphery of one end of the core is provided in an annular recess formed in an annular plate portion at one end of the supporting hardware. At the same time, the inclined projection provided on the outer periphery near the other end of the cylindrical part of the support metal is engaged with the protrusion on the inner periphery of the core, thereby making it easy to remove the support metal after casting is completed. Accurate centering of the core through the fitting of the flange and clamping of the seven rungs of the core between the rotating metal frame and the annular plate, and engagement between the protrusions and the slope protrusions, ensure that the core remains stable during casting rotation. Rotation and deflection are prevented, and engagement between the slope projection and the protrusion prevents the core from being pulled out during transport of the front lid.

An embodiment of the present invention will be described below with reference to FIGS. 4 and 5. Reference numeral 11 denotes a front cover consisting of a support metal fitting 12 and a core 13.

The supporting hardware 12 has a cylindrical portion 14 into which the core 13 is loosely fitted.
and an annular plate part 15 that integrally projects from the outer periphery of one end 14a of the cylindrical part 14 and whose outer periphery fits into the inner periphery of one end of the rotary metal frame 5. Other end 14b
An annular recess 16 whose inner periphery reaches the outer periphery of the cylindrical portion 14 and whose outer periphery reaches near the outer periphery of the annular plate portion 15 is formed on the side facing the side.

The core 13 is composed of a sand mold molded by the isocure method, the peg set method, the shell method, etc., and the inner periphery of the cylindrical main body portion 17 is loosely fitted to the outer periphery of the cylindrical portion 14 at intervals,
A flange portion 18 that fits into the outer peripheral side surface 16a of the annular recess 16 projects from the outer periphery of one end 17a of the main body portion.

The outer periphery of the main body 17 of this core 13 constitutes the mold surface of the inner periphery of one end of the product to be cast, and the side surface of the seventh run section 18 opposite to the annular recess 16 constitutes the mold surface of the one end surface of the product. Configure.

Further, a collar 19 is provided on the other end 17b of the main body portion 17 and projects inward in the radial direction to prevent the molten metal from jumping out toward one end of the rotating metal frame.

As shown in FIG. 5, on the inner periphery of the main body 17 of the core 13, protrusions 20 are formed at appropriate intervals in the circumferential direction and extend over almost the entire length along the axial direction. On the outer periphery of the end 14b, sloped protrusions 21 that correspond to each protrusion 20 and engage with the protrusion 20 are protruded.

The sloped protrusion 21 has a circumferential slope whose cross-sectional height increases as it moves toward the opposite side to the rotational direction of the support hardware 12, that is, the rotational direction of the rotating metal frame 5 (in the direction of the arrow in FIG. 5). It has an engaging surface, and this inclined retaining surface is the protrusion 20.
engage with.

Incidentally, the slope protrusion 21 is not limited to the other end 14b of the cylindrical portion, but may be arranged near the other end 14b, and in short, it is sufficient that it is located closer to the other end than the center of gravity of the core 13.

In addition, the number and size and shape of these protrusions 20 and slope protrusions 21 can be arbitrarily selected depending on the diameter of the product, the shape of one end, etc., but the general tendency is to increase the number and make the dimensions smaller. is preferred.

In the above configuration, the front cover 11 is assembled by inserting the separately molded core 13 into the support hardware 12. At this time, the protrusion 20 on the inner circumference of the core 13 After inserting the core 13 so that it is positioned between the protrusions 21, the protrusions 2 are rotated in the opposite direction to the direction of rotation during casting.
0 and the slope protrusion 21 are engaged with each other.

The front cover 11 thus assembled is fitted onto the inner periphery of one end of the rotary metal frame 5 by a suitable conveying means, and is pressed and fixed to the rotary metal frame 5 by fixing means such as a taper pin, hydraulic pressure, or a claw.

In this state, the flange portion 18 of the core 13 is fitted into the annular recess 16, so that the core 13 is aligned with the rotating metal frame 5 via the annular plate portion 15, and the outer peripheral portion of the flange portion 18 is aligned with the annular plate portion 15. It is fixed to the rotating metal frame 5 by being pressed against the rotating metal frame 5 by the portion 15, and at the same time, the protrusion 20 and the slope protrusion 21 are fixed to the rotating metal frame 5.
It is also fixed through the support hardware 12 by engagement with the support hardware 12.

This engagement also performs an auxiliary centering action at the other end of the core 13.

Therefore, there is no risk that the core 13 will rotate or shake during the casting rotation and be damaged.

When casting is completed, the fixing means for the supporting hardware 12 is released and the supporting hardware 12 is immediately removed from the rotary metal frame 5.

At this time, the attachment to the core 13 from the inside in the radial direction is as follows:
Since the slope protrusion 21 is only secured to the protrusion 20, it can be easily removed.

After the removed supporting hardware 12 is cleaned and cooled, the core 13 is inserted again and used for casting.

According to the front cover of the present invention, as is clear from the above description,
Since the core loosely fits into the cylindrical part of the support metal, it is easy to remove the support after casting is completed, and the flange of the core fits into the annular recess of the support metal, making it easy to remove the support metal after casting is completed. The core is aligned accurately, the flange of the core is pressed against the rotating metal frame by the annular plate of the support metal, and the protrusions of the core are engaged with the sloped protrusions of the support metal. This ensures that the core is aligned and fixed in the rotating metal frame, so there is no risk of the core being damaged during casting rotation, and the above-mentioned engagement prevents the core from being pulled out during transportation. Nor.

[Brief explanation of the drawing]

Figure 1 is a vertical cross-sectional view showing the schematic configuration of a centrifugal casting mold, Figure 2
The figure is a longitudinal sectional view of a conventional front cover, FIG. 3 is a view taken along the line II in FIG. 2, FIG. 4 is a longitudinal sectional view of a front cover according to the present invention, and FIG. −■ It is a sectional view taken along the arrow. 11...Front lid, 12...Support hardware, 1
3... Core, 14... Cylindrical part, 15.
...... Annular plate portion, 16...... Annular recessed portion, 17
...Body portion, 18...7 langouse portion, 20...Protrusion, 21...Slope protrusion.

Claims (1)

[Claims] 1. A centrifugal casting mold consisting of a support metal fitting with an annular plate protruding from the outer periphery of one end of the cylindrical part that fits into a part of the inner periphery of the rotating metal frame, and a core that loosely fits on the outer periphery of the cylindrical part. In the front lid of
Seven rungs protruding from the outer periphery of one end of the core are fitted into an annular recess formed in the annular plate portion, and protrusions extending along the axial direction are provided at appropriate intervals on the inner periphery of the core, and A front lid for a centrifugal casting mold, characterized in that a slope protrusion whose cross-sectional height changes as it moves in the circumferential direction is provided on the outer periphery near the other end of the cylindrical part.