Casting Apparatus

This application claims priority to Japanese Patent Application No. 2024-071062 filed on Apr. 25, 2024, incorporated herein by reference in its entirety.

The present disclosure relates to a casting apparatus.

In production of a die-cast product, a method is used in which the die-cast product is immersed in water to be cooled after casting (e.g., see Japanese Unexamined Patent Application Publication No. 2015-27684 (JP 2015-27684 A)).

Now, as described in JP 2015-27684 A, when the die-cast product after casting is immersed in water to be cooled, the die-cast product may exhibit distortion. When distortion occurs, it is necessary to correct the cooled die-cast product using a press machine or the like. However, correction of the die-cast product leads to an increase in costs of the product.

Accordingly, an object of the present disclosure is to suppress distortion of a die-cast product during cooling following casting.

A casting apparatus according to the present disclosure is

As described above, the coolant is sprayed in a state in which the die-cast product is held by the mold, and accordingly deformation of the die-cast product at the time of cooling can be suppressed by the mold, and distortion of the die-cast product can be reduced. Also, the die-cast product is released from the mold by the ejecting device and thereafter sprayed with the coolant, and accordingly a situation can be suppressed in which the die-cast product becomes fixed to the mold when the coolant is sprayed, and cannot be removed from the mold. Note that the term “substantially horizontal direction” as used herein includes not only a horizontal direction in a strict sense, but also directions that are slightly tilted from the horizontal direction. For example, the present disclosure also includes directions tilted by about 2° to 3° from the horizontal direction in a strict sense.

In the casting apparatus according to the present disclosure, the processor may be configured to eject the die-cast product from the mold by the ejecting device in the substantially horizontal direction, such that an amount of ejecting of the die-cast product from the mold is shorter than a length in a mold removal direction of a portion at which the die-cast product and the mold overlap in an up-down direction.

Thus, the die-cast product can be held from below by the mold in a state in which the die-cast product is ejected from the mold.

In the casting apparatus according to the present disclosure, the processor is configured to cause the ejecting device to eject the die-cast product from the mold in the substantially horizontal direction such that the amount of ejecting of the die-cast product from the mold is less than 5 mm.

Thus, by setting the amount of ejection of the die-cast product to be less than 5 mm, the die-cast product can be held by the mold from below.

In the casting apparatus according to the present disclosure,

In this way, the coolant injection nozzle is advanced to between the movable mold and the fixed mold to cool the die-cast product, and accordingly the size of the casting apparatus can be made to be compact.

The present disclosure can suppress distortion of a die-cast product during cooling following casting.

Hereinafter, the casting apparatusof the embodiment will be described with reference to the drawings. As illustrated in, the casting apparatusincludes a mold, a mold clamping device, an ejecting device, an injection device, an exhaust pipe, a spraying device, and a control unit. In the drawings, reference numerals FR, LH, UP denote the front, left, and upper sides of the casting apparatus, respectively. The opposing orientations of FR, LH, UP are rearward, rightward, and downward, respectively. Further, the front and left are directions in the horizontal plane, and the upper and lower are directions in the vertical plane.

The moldincludes a fixed moldand a movable mold. The fixed moldincludes a main moldand an insert. The movable moldincludes a main moldand an insert. Here, the insertsandare portions of the fixed mold. movable moldthat are replaced according to the die-cast productto be molded. The main moldsandare portions commonly used for the die-cast productto be molded. Further, the main moldsandare portions fixed to the fixed platenand the movable platenof the mold clamping devicedescribed later.

The mold clamping deviceincludes a fixed platen, a movable platen, a tie bar, and a driving unit. The fixing platenis fixed to a distal end portion of a tie barwhich is a rod member. The movable platenis disposed so as to face the fixed platen, and moves forward along the tie barby the driving unit.

A fixed moldis attached to the fixed platen, and a movable moldis attached to the movable platen. The mold clamping deviceopens and closes the moldby horizontally moving the movable moldin the front-rear direction together with the movable platen. Then, the movable moldis moved forward and pressed against the fixed mold, whereby the mold clamping of the moldis performed.shows a moldin a clamped state by a mold clamping device. When the moldis clamped, a cavityis formed between the fixed moldand the movable mold. The cavityis a portion of the internal space of the moldhaving a shape corresponding to the shape of the die-cast product(see). Here, the die-cast productmay be, for example, a vehicle body structural member.

The injection devicepumps the molten metal, which is the material of the die-cast product, into the cavityof the moldas indicated by the white arrow in. Further, the air in the cavityis exhausted from the exhaust pipeby a vacuum device (not shown) (see an arrow in). The ejecting deviceincludes an ejecting pin, an ejecting plate, and an ejecting drive unit. The ejecting devicereleases the die-cast productfrom the movable moldin a substantially horizontal direction by causing the ejecting pinsto project horizontally toward the front when the moldis separated. Here, the substantially horizontal direction includes not only a strict horizontal direction but also a direction slightly inclined from the horizontal direction. For example, the substantially horizontal direction includes a direction inclined by about 2° to 3° from the strict horizontal direction.

A spraying deviceis disposed above the mold. The spraying deviceincludes a main body, a telescopic arm, a release agent injection nozzle, and a coolant injection nozzle. The main bodyis attached to a frame (not shown) and moves in the front-rear-left-right direction. The telescopic armis attached to the main bodyand expands and contracts in the up-down direction. A release agent injection nozzleand a coolant injection nozzleare attached to the distal end of the telescopic arm. The release agent injection nozzlesprays the release agent toward the movable mold. The coolant injection nozzlesprays the coolant onto the die-cast productafter casting. The release agent injection nozzleand the coolant injection nozzleare movable in the front, rear, left, right, up and down directions by the main bodyand the telescopic arm.

The control unitis a computer including a CPUthat is a processor that performs information processing therein, and a memorythat stores control programs and control data. The driving unitof the mold clamping device, the ejecting drive unitof the ejecting device, the injection device, and the spraying deviceare connected to the control unit, and operate according to an instruction from the control unit.

Next, with reference to, the operation of the casting apparatuswill be described. As shown in, a fixed moldand a movable moldare setin the casting apparatus. The fixed moldand the movable moldare separated from each other by the mold clamping device, and a space is provided between the fixed moldand the movable mold.

As shown in stepof, CPUof the control unitextends the telescopic armof the spraying devicedownward to advance the release agent injection nozzlebetween the fixed moldand the movable mold. Then, CPUsprays the release agent onto the movable moldas shown inwhile scanning the release agent injection nozzlevertically and horizontally with respect to the movable moldby the main bodyand the telescopic arm.

When the spraying of the release agent is completed, CPUof the control unitoperates the driving unitof the mold clamping deviceto move the movable moldforward together with the movable platen, as shown in stepof. Then, CPUpresses the movable moldagainst the fixed moldto clamp the mold(see). Then, CPUof the control unitoperates the injection devicein stepof, as shown in, injecting molten metal into the cavityof the mold.

CPUremains clamped for a predetermined period of time at stepof. Thereafter, in stepof, CPUoperates the driving unitof the mold clamping deviceto move the movable moldbackward together with the movable platen, as shown in, and separates the moldinto the fixed moldand the movable mold. When the moldis separated after casting, a die-cast productis formed in the region of the cavityshown in.

Next, in stepof, CPUoperates the ejecting drive unitof the ejecting deviceto move the ejecting pinforward, and releases the die-cast productforward from the movable mold, as shown in.

As shown in, the insertof the movable moldincludes an upper portion, a lower portion, and a central portion. The central portionprotrudes forward from the upper portionand the lower portionto form a convex portionof the die-cast product. The central portionhas a height H. The central portionhas a tapered cross section in which the length of the upper and lower portions decreases toward the front. The upper surfaceof the central portionis inclined downward toward the front, and the lower surfaceis inclined upward toward the front. Incidentally, the inclination angle of the upper surfaceand the lower surfacemay be any angle as long as it is a die-cutting gradient for releasing the die-cast productfrom the movable mold, and may be, for example, about 1° to 2°. In, the inclination angle is displayed larger than the actual inclination angle.

The die-cast productincludes an upper side portion, a lower side portion, a central convex portion, an upper plate, and a lower plate. The convex portion, the upper plate, and the lower plateare formed by the upper surfaceand the lower surfaceof the central portionof the insert. The inclination angle of the inner surface of the upper plateis the same as the inclination angle of the upper surface. The inclination angle of the inner surface of the lower plateis the same as the inclination angle of the lower surface. These inclination angles may be about 1° to 2°, similar to the inclination angles of the upper surfaceand the lower surface.

In stepof, CPUcauses the ejecting deviceto push the upper side portion, the lower side portion, and the convex portionof the die-cast productout of the upper portion, the lower portion, and the central portionof the insertby the ejecting amount D, as shown in. As a result, a gap of the ejecting amount D is formed between the upper side portionand the upper portion, between the lower side portionand the lower portion, and between the convex portionand the central portion. A gap is also formed between the inner surface of the lower plateand the lower surfaceof the insert.

On the other hand, a part of the inner surface of the upper plateand a part of the upper surfaceof the insertare in contact with each other in the vertical direction. As described above, the inclination angle of the upper surfaceis about 1° to 2°. Thus, when CPUpushes the die-cast productforward with the ejecting device, the die-cast productis pushed forward obliquely down 1° to 2° along the draft angle provided on the upper surfaceof the insert. In this way, the die-cast productis ejected in a substantially horizontal direction along the draft angle. Since the inclination angle of the upper surfaceis about 1° to 2°, the load of the die-cast productis supported by the upper surfaceof the insertat a portion (B portion in) where the upper plateand the upper surfaceoverlap in the up-down direction. Accordingly, the die-cast productis held by the movable mold.

Before the die-cast productis ejected, the front portion of the inner surface of the upper plateand the entire upper surfaceof the insertoverlap in the vertical direction. Here, since the height of the central portionof the insertis H, the length in the die-cutting direction of the portion where the die-cast productand the movable moldoverlap in the vertical direction is H. Therefore, CPUpushes the die-cast productsubstantially horizontally such that the ejecting amount D is shorter than the height H. As a result, the die-cast productcan be held by the movable mold. Here, the ejecting amount D can be freely set as long as it is shorter than the height H, but may be, for example, less than 5 mm.

As shown in, after the die-cast productis ejected from the movable mold, CPUproceeds to stepofto spray the coolant to the die-cast product.

As shown in, CPUextends the telescopic armof the spraying devicedownward to advance the coolant injection nozzlebetween the fixed moldand the movable mold. Then, as shown in, CPUsprays the coolant onto the surface of the die-cast productheld by the movable moldwhile scanning the coolant injection nozzlein the vertical and horizontal directions with respect to the movable moldby the main bodyand the telescopic arm.

Then, when the temperature of the die-cast productdecreases, CPUgrasps the die-cast productwith a robotic arm (not shown) and removes it from the movable mold, as shown in stepof.

As described above, in the casting apparatus, since the coolant is sprayed in a state where the die-cast productis held by the movable mold, deformation of the die-cast productat the time of cooling can be suppressed by the movable mold, and distortion of the die-cast productcan be reduced. Further, since the die-cast productis released from the movable moldby the ejecting deviceand then the coolant is sprayed, it is possible to prevent the die-cast productfrom being fixed to the movable moldand cannot be punched out when the coolant is sprayed.

In the above description, the die-cast productis ejected from the movable moldby the ejecting device, and the die-cast productis held by the movable moldto spray coolant, but the present disclosure is not limited thereto. For example, the ejecting devicemay be disposed on the side of the fixed mold, and the ejecting devicemay be configured to eject the die-cast productfrom the fixed mold, hold the die-cast productin the fixed mold, and spray the coolant.