JPH08197188A - Apparatus for producing long-sized casting - Google Patents

Abstract

PURPOSE: To decrease the flashes and distortions of a long-sized casting integrally formed with an intermediate part and front end parts of a sectional area larger than the sectional area of the intermediate part by using a large amt. of molten metal on both ends of the intermediate part and to obtain the defectless long-sized casting by producing the long-sized casting with simple equipment. CONSTITUTION: A die 1 is used in a gravity casting method and the die 1 is formed with a cavity 6 corresponding to the long-sized casting 5 integrally formed with the intermediate part 11 and the front ends 12 of the sectional area larger than the sectional area of the intermediate part 11 at both ends of the intermediate part 11. The cavities 16 for the front ends corresponding to the front ends 12 are arranged on both sides in the longitudinal direction of the die 1 and a cavity 17 for the intermediate part corresponding to the intermediate part 11 is formed toward the longitudinal direction of the die 1 between these cavities 16 for the front ends. A sprue 4a is arranged in the position between the cavities 16 for the front ends at both ends alongside the cavity 17 for the intermediate part and runners 11 extending from the sprue 4a are connected to the cavities 16 for the respective front ends.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for producing a long casting by a heavy casting method using a die.

[0002]

2. Description of the Related Art Conventionally, when a long casting is manufactured, it is necessary to surely supply the molten metal to every corner of the long cavity, so that a pressure casting method is generally used.

[0003]

However, in the case of producing a long casting by a pressure casting method as in the prior art, the equipment is large and, especially, a large amount of material is present at the intermediate portion and both ends of this intermediate portion. In the case of a long casting integrally formed with a large cross-sectional tip portion of the intermediate portion using a molten metal, due to the bias of the temperature distribution of the long die according to the casting shape,
The mold is thermally deformed, and the flash and distortion become remarkable.

The present invention has been made in view of the above circumstances, and integrally forms an intermediate portion and a tip portion having a larger cross-sectional area than the intermediate portion by using a large amount of molten metal at both ends of the intermediate portion. The present invention aims to obtain a sound long casting by reducing the flash and distortion of the casting while producing the above long casting with simple equipment.

[0005]

In order to achieve this object, the invention according to claim 1 is a mold used in a gravity casting method, wherein the mold has an intermediate part and both ends of the intermediate part. A cavity corresponding to a long casting integrally formed with a tip portion having a larger cross-sectional area than the intermediate portion is formed, and tip cavity portions corresponding to the tip portion are arranged on both sides in the longitudinal direction of the mold. In addition, an intermediate portion cavity corresponding to the intermediate portion is arranged between these tip portion cavities in the longitudinal direction of the mold, and the tip portions of the end portions on the sides of the intermediate portion cavity are disposed. The apparatus for producing a long casting is characterized in that a sprue is arranged at a position between the casting cavities and a runner extending from the sprue is connected to each of the tip cavities.

According to a second aspect of the present invention, in the apparatus for producing a long casting according to the first aspect, the die is composed of an upper die and a lower die, and an intermediate portion of the long casting is provided. Is a channel shape of the upper opening, the cavity for the intermediate portion, the lower surface and the side surface of the intermediate portion of the casting is formed by the lower mold, the inner surface side of the channel shape of the intermediate portion of the casting is formed by the upper mold, It is an apparatus for producing long castings.

[0007]

According to the first aspect of the present invention, since the sprue is arranged on the side of the cavity for the intermediate portion and between the cavities for the tip portions at the both ends, the tip portion which becomes a high temperature region in the mold is provided. The cavity and the sprue are arranged in a distributed manner in the longitudinal direction of the mold, the uneven distribution of the temperature distribution in the longitudinal direction of the mold is suppressed, the thermal deformation of the mold is reduced, and the flash and distortion are reduced.

Further, since the runner extending from the sprue is connected to each of the tip cavities, the molten metal supplied has a large capacity in the cavity and passes through the tip cavities maintained at a high temperature level. Since it reaches the cavity for the middle part, heat dissipation from a small amount of molten metal for filling the cavity for the middle part with a small capacity is suppressed, and the decrease in the melt temperature is reduced, so that it is possible to ensure good quality in every corner of the cavity. A molten metal can be supplied, and a sound casting can be obtained.

Therefore, although the long casting is integrally formed with the intermediate portion and the end portions having a larger cross-sectional area than the intermediate portion at both ends of the intermediate portion, the gravity casting method is used for producing with a simple facility. Reduces flash and distortion of the casting,
A sound casting can be obtained.

According to the second aspect of the present invention, the middle portion of the long casting has a channel shape with an upward opening, and the cavity for the middle portion has the lower surface and the side surface of the middle portion of the casting formed by a lower mold. Since the channel-shaped inner surface side of the middle portion of the casting is formed by the upper mold, it is easy to effectively install the feeder so as to be continuous with the open edge portion of the middle portion, if necessary.

Therefore, even in the middle part where the runner is far from the sprue as described above, shrinkage cavities are prevented by the riser, and the elongated casting of the above-mentioned shape can be obtained as a sound product by gravity casting. It will be more certain.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments shown in the drawings.

In FIG. 2, reference numeral 1 denotes a gravity casting mold (hereinafter, simply referred to as a mold, which corresponds to the manufacturing apparatus in the present invention), 2 is a lower mold, 3 is an upper mold, 4 is a sprue part.

A cavity 6 corresponding to the shape of the long casting 5 is formed in each of the lower mold 2 and the upper mold 3, and the spout 4a formed in the sprue part 4 is formed in the cavity 6.
The runners 7 connecting from are connected.

Therefore, when the molten metal is supplied from the sprue portion 4, the molten metal is filled into the cavity 6 via the runner 7, and the molten metal is solidified to obtain a long casting 5 having a predetermined shape by the gravity casting method. To be

First, the long casting 5 in this embodiment will be described.

The long casting 5 of this embodiment is a so-called thin casting, and has a structure in which a thin plate-shaped casting portion is bent over the whole.

As shown in phantom in FIG. 1, the elongated casting 5 is formed by integrally forming an intermediate portion 11 and tip portions 12 at both ends of the intermediate portion 11, for example, It is a large-sized part that is used as a part of the body frame of a passenger car and has a total length (in the left-right direction in Fig. 1) of about 1.5 m and is made of aluminum alloy (AC4CH).

As shown in FIG. 3, the intermediate portion 11 is formed in a channel shape having a U-shaped cross section, and in order to improve its bending rigidity while being lightweight, a plurality of intermediate portions 11 are provided at appropriate intervals in the longitudinal direction. The rib 13 is installed.

The tip portion 12 has a function as a bracket for connecting to another vehicle body frame and as a bracket for mounting various other parts such as suspension parts of an automobile.

Therefore, the cross-sectional area of the casting portion in the cross section of the tip portion 12 in the direction orthogonal to the longitudinal direction of the long casting 5 is larger than the same cross-sectional area of the intermediate portion 11 excluding the ribs 13. Has become.

Therefore, in forming such a long casting 5, most of the molten metal is used for forming the tip portion 12, while the amount of molten metal used for forming the intermediate portion 11 is small.

In the die 1 for producing such a long casting 5 by gravity casting, tip end cavities 16 corresponding to the respective tip portions 12 are provided at both ends of the die 1 in the longitudinal direction. The cavities 16 for the tip end portions are formed so as to be separated from each other, and the cavities 16 for the tip end portion are connected by the cavity 17 for the intermediate portion formed in the longitudinal direction of the mold 1.

A sprue 4a is disposed laterally of the intermediate cavity 17 and between the distal cavities 16. That is, in the mold 1, the tip end cavity 16 on one end side, the sprue 4a, and the tip end cavity 16 on the other end side are sequentially arranged in the longitudinal direction of the die 1 (left-right direction in FIG. 1). ing. Therefore, in the mold 1, since the tip end cavities 16 and the sprue 4a, which have high temperature levels, are located dispersedly in the longitudinal direction of the mold 1, the temperature distribution in the longitudinal direction of the mold 1 is increased. Is suppressed, and the thermal deformation of the die 1 during casting is reduced.

A molten aluminum alloy is supplied as shown by the arrow in FIG.
The molten metal is the first metal which is installed in the longitudinal direction of the mold 1.
Reach Runway 21. The molten metal reaching the first runway 21 is
The flow is divided into left and right at the merging portion, and heads to the left and right tip end cavities 16, respectively.

The opposite ends of the first runner 21 are joined to the second runner 22, respectively.

These second runners 22 are formed so as to surround the peripheries of the respective tip end cavities 16 corresponding thereto. This is for suppressing the heat radiation from the molten metal supplied to each tip cavity 16 and maintaining the temperature level of the molten metal supplied to the intermediate cavity 17.

In this embodiment, the second runner 22 is formed so as to surround only the portion of the tip end cavity 16 on the side of the sprue 4a. The shape of the cavity 16 for enclosing a portion of the cavity 16 on the opposite side of the sprue 4a may also be formed.

A ceramic filter 23 having a large number of pores is installed in each of the second runners 22, and the tips are branched into a plurality, and each of the branched tips is pushed. It is connected to the proper location of the tip end cavity 16 via hot water 24.

That is, the molten metal supplied from the second runner 22 to the tip end cavity 16 is all in the filter 2
As a result, the impurities are removed and the flow of the molten metal is laminarized by passing through No. 3, and then the molten metal is smoothly supplied to the tip cavity 16 and the intermediate cavity 17 by passing through the feeder 24. Is secured.

As described above, the first and second runners 21 and 22 extending from the sprue 4a are connected to the tip end cavity 1 respectively.
6, the tip cavity 1 has a large capacity and is maintained at a high temperature level in the cavity 6.
The molten metal can be supplied to the cavity 17 for the intermediate portion via 6

Therefore, the heat can be supplied while suppressing the heat radiation from a small amount of the molten metal for filling the small-capacity intermediate cavity 17, and the decrease in the temperature of the molten metal supplied to the intermediate cavity 17 is reduced. , Cavity 6
It is possible to reliably supply good molten metal to every corner of the
A sound casting can be obtained by the gravity casting method performed with simple equipment.

Further, in this embodiment, the long casting 5
Of the intermediate part 11 of the elongated casting 5 is formed by the lower mold 2 on the lower surface and the side surface of the intermediate part 11 of the elongated casting 5 to form the channel of the intermediate part 11 of the elongated casting 5. The inner surface side of the shape is formed by the upper mold 3.

Therefore, it is easy to effectively install the feeder 25 (shown by an imaginary line in FIG. 1) so as to be continuous with the open edge of the intermediate portion 11 if necessary.

This means that the intermediate portion 1 in which the first and second runners 21 and 22 are far from the sprue 4a as described above.
Even if it is 1, it becomes more reliable to obtain the elongated casting 5 having the above-mentioned shape as a sound one free from distortion by gravity casting by installing the feeder 25 at the position of the rib 13, for example.

Although the mold 1 of the embodiment described above is provided with the single sprue 4a and the first and second runners 21 and 22 are formed, the present invention is not limited to this. Alternatively, the sprue may be formed for each tip cavity 16 at a position between the tip cavities 16, and the runner extends from the spout 4a toward each tip cavity 16. As a matter of fact, they may be directly connected.

[0037]

As described above, according to the first aspect of the invention, since the sprue is arranged at the side of the cavity for the intermediate portion and between the cavities for the tip portions at the both ends, The tip cavity and the sprue, which are the high temperature region in the mold, are dispersed and arranged in the longitudinal direction of the mold, the uneven distribution of the temperature distribution in the longitudinal direction of the mold is suppressed, and the thermal deformation of the mold is reduced. Reduces flash and distortion.

Further, since the runner extending from the sprue is connected to each of the tip cavities, the molten metal supplied has a large capacity in the cavities and passes through the tip cavities maintained at a high temperature level. Since it reaches the cavity for the middle part, heat dissipation from a small amount of molten metal for filling the cavity for the middle part with a small capacity is suppressed, and the decrease in the melt temperature is reduced, so that it is possible to ensure good quality in every corner of the cavity. A molten metal can be supplied, and a sound casting can be obtained.

Therefore, although it is a gravity casting method for producing a long casting in which a middle portion and both ends of the middle portion are integrally formed with a tip portion having a larger cross-sectional area than the middle portion by a gravity casting method, Reduces flash and distortion of the casting,
A sound casting can be obtained.

According to the second aspect of the present invention, the middle part of the long casting is formed into a channel shape with an upward opening, and the cavity for the middle part is formed by forming a lower surface and a side surface of the middle part of the casting with a lower mold. Since the channel-shaped inner surface side of the middle portion of the casting is formed by the upper mold, it is easy to effectively install the feeder so as to be continuous with the open edge portion of the middle portion, if necessary.

Therefore, even in the middle part where the runner is far from the sprue as described above, shrinkage cavities are prevented by the riser, and a long casting of the above shape can be obtained as a sound product by gravity casting. It will be more certain.

[Brief description of drawings]

FIG. 1 is a die plan view of a die.

FIG. 2 is an overall side view of a mold.

FIG. 3 is an enlarged central cross-sectional view of a main part of a lower mold.

[Explanation of symbols]

 1 Gravity Casting Die 2 Lower Die 3 Upper Die 4 Gate 4a Gate 5 Long Cast 6 Cavity 7 Runner 11 Intermediate Part 12 Tip 16 Tip Cavity 17 Intermediate Cavity 21 First Runner 22 No. 2 runways

Claims (2)

[Claims] 1. A mold used in a gravity casting method, wherein a long casting is integrally formed with an intermediate part and both ends of the intermediate part and tip parts having a larger cross-sectional area than the intermediate part. A cavity corresponding to the tip portion is formed, the tip portion cavity corresponding to the tip portion is arranged on both sides in the longitudinal direction of the mold, and an intermediate portion corresponding to the intermediate portion is provided between these tip portion cavities. The cavity for casting is arranged in the longitudinal direction of the mold, and the sprue is arranged at a position lateral to the cavity for the middle portion and between the cavities for tip portions at the both ends, and the runner extending from the spout is An apparatus for producing a long casting, which is connected to each tip cavity. 2. The apparatus for producing a long casting according to claim 1, wherein the mold is composed of an upper die and a lower die, and an intermediate portion of the long casting has an upward opening channel shape. The apparatus for producing a long casting is characterized in that the part cavity is formed by forming a lower surface and a side surface of a middle portion of the casting with a lower die and forming an inner surface side of the channel shape of the middle portion of the casting with an upper die.