JPH08197228A - Apparatus for squeezing molten metal - Google Patents

Abstract

PURPOSE: To surely and easily obtain a good quality product by arranging a large scaled first hydraulic cylinder around a center pin and directly fitting an insert stem to the end surface of a piston thereof. CONSTITUTION: A fixed die 3 to a fixed plate 1 and a movable die 12 to a movable plate 7 are fitted, respectively. The center pin 18 is shiftable in the die opening/closing direction and a gate at the fixed die side is opened/closed with this pin. The cylindrical insert stem 13 for pressurizing molten metal, arranged around the center pin 18 so as to be slidable in the die opening/closing direction and faced to a cavity 14 at this tip part, or plural first pressurizing pins arranged on the concentrical circle, are arranged to the movable die side. Further, the large scaled first hydraulic cylinder 9 having the cylindrical piston 10 is arranged around the center pin 18 at the axial center part of the movable plate 7, and the insert stem 13 or the first pressurizing pin is directly fitted to the end surface of the piston 10 thereof. By this constitution, the pressurizing force is concentrated to the part needing the strength and the molten metal squeezing can be executed to this part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for filling a mold cavity with molten metal and forging the molten metal.

[0002]

2. Description of the Related Art Conventionally, for example, when molding aluminum wheels for automobiles by a squeeze die casting method,
Japanese Patent Publication No. 3-4297, Japanese Patent Publication No. 3-25264, Japanese Patent Application No. 5-296293, Japanese Patent Application No. 6-25
Molded using methods and equipment as described in US Pat. That is, in these,
Inside the mold cavity formed between the lower fixed mold and the upper movable mold, a melt passage with a diameter smaller than the inner diameter of the injection sleeve that is arranged by joining the fixed mold from the lower side to the fixed mold. Immediately after casting the molten metal into the mold cavity through the through hole, a pin that is slidably attached to the movable mold and that is slightly smaller than the diameter of the small-diameter melt passage in the fixed mold is immediately inserted. It was formed by advancing and inserting the tip of the pin into the melt passage of the small diameter.

All of these are aimed at producing a dense product. However, in the case of the squeeze die casting method as disclosed in Japanese Patent Publication No. 3-4297 and Japanese Patent Publication No. 3-25264, the axis of the movable mold is immediately after the molten metal is filled in the mold cavity. Since only the feeder pin provided at the core is moved forward,
Although the effect of pushing is obtained to some extent, only the small area in the center of the cast product that has already hardened is pushed, so that the entire molten metal in the mold cavity is replenished. However, the feeding power was not sufficiently transmitted. Further, when the feeder force due to the action of the center pin for the feeder is transmitted to the molten metal in the mold cavity, the pressure acts to push down the injection plunger, reducing the effect of the feeder.

For these reasons as well, sufficient riser is not always made, and a sufficiently satisfactory and dense product is not always obtained. Further, during the time when the center pin replenishes the molten metal with respect to the solidification shrinkage of the molten metal, the injection plunger continues to pressurize and cannot move to the next operation, resulting in a long casting cycle time. In addition, air remained in the mold, causing defects.

In the above-mentioned conventional molten metal forging method, the molten metal is cast into the mold cavity while the movable mold is temporarily stopped during the mold clamping just before the mold is completely clamped.
After that, the entire movable mold was further advanced to completely mold and perform the molten metal forging, so that the entire molten metal in the mold cavity was pushed in the mold clamping direction, and the unit pressure was It was too low to expect a feeder effect from the mold structure, and it was not always possible to obtain a product with consistent product accuracy, compactness and mechanical strength.

Therefore, in order to solve these problems, the inventor of the present invention, as described in Japanese Patent Application No. 6-25514, has a fixed die and a movable plate having a plurality of cylinders built therein. A movable die attached via a head, attached to a movable plate and slidably provided inside the movable die,
In addition, by using a molten metal forging device equipped with a center stem and a nest stem whose front end faces the cavity, hydraulic pressure is applied to the rod side chamber of each cylinder to move the nest stem and the center pin into a movable mold. The mold is clamped by moving the movable mold and the insert stem forward at the same time in a state of being relatively retracted with respect to the mold, and the mold is filled with molten metal while the mold clamping operation is continued. While the pressure is increasing in the head side chamber of the center pin cylinder, the center pin is moved forward and closed to the gate of the mold while maintaining the mold clamping force, preventing the molten metal from leaking into the mold cavity. In this state, the nesting stem is moved forward to increase the pressing force acting on the molten metal in the cavity to enhance the forging effect, and further the injection plunger is retracted early to shift to the next operation. It invented the molten metal forging method to reduce the forming cycle time.

[0007]

[Problems to be Solved by the Invention] Japanese Patent Application No. 6-25514
In the invention of No. 3, since the pressurization of the nest stem is performed by the hydraulic cylinders arranged on the circumference, the structure becomes complicated, the cross head as a strength member becomes large, and the movable plate cannot be made small. In addition, it is difficult to dispose a hydraulic cylinder that pressurizes the pressurizing pin to prevent the sink marks in the thick portion on the outer periphery of the cylindrical product. Further, the gas in the mold must be discharged during casting, but if a pressure pin can be arranged on the outer periphery, gas can be discharged by utilizing this pin to produce a product without bubbles.

[0008]

According to the present invention, a fixed mold attached to a fixed plate and a movable mold attached to a movable plate are provided and are movable in the mold opening / closing direction. Center pin that opens and closes the gate of, and is arranged around the center pin, is slidable in the mold opening and closing direction, and is located on a cylindrical insert stem or concentric circle for pressurizing the melt with the tip facing the cavity. In a molten metal forging device in which a plurality of first pressure pins are provided on the movable mold side, a large-sized first piston having a cylindrical piston around a center pin located at the central portion of the axis of the movable plate is used. One hydraulic cylinder was provided, and the nest stem or the first pressure pin was directly attached to the end surface of the piston of the first hydraulic cylinder.

Further, a plurality of second hydraulic cylinders are arranged concentrically inside the movable plate, and a ring-shaped crosshead is connected to the tip end portion of each piston rod of the second hydraulic cylinder to form a cylindrical cavity. A plurality of second pressure pins provided with the tip end facing the end face portion were attached to the crosshead. Further, the tip of the second pressure pin is used as an opening / closing valve, and a groove extending in the axial direction is provided on the outer peripheral surface of the second pressure pin leaving the tip, and a gas venting device is provided behind this groove. Connected.

[0010]

First, in the chamber on the rod side of the cylinder for the telescopic stem or the first pressure pin with the built-in movable plate and the cylinder for the second pressure pin when the second pressure pin is used. With the hydraulic stem actuated and the telescopic stem and the pressure pin are retracted relative to the movable mold, the movable platen is moved forward to advance the movable mold and the nested stem at the same time. Perform the tightening operation. In this state, the movable mold is completely pressed against the fixed mold for proper mold clamping, and the mold clamping force is transmitted from the movable plate to the fixed mold through the movable mold.

Next, when the mold clamping is completed, the second pressurizing pin is advanced so that the gas can pass therethrough. When the molten metal begins to be filled in the cavity by the injection operation, the gas is discharged from the passage around the second pressurizing pin. Immediately before the completion of filling, pull up the pin to block the passage and prevent molten metal from flowing out. When the filling of the molten metal in the cavity is completed, the hydraulic pressure in the chamber on the head side of the center pin cylinder is increased after a certain period of time while the mold clamping operation is being continued. Then, the center pin moves forward and its tip closes the gate of the mold.

After that, when the hydraulic pressure in the head side chamber of the insert stem or the cylinder for the first pressure pin and the cylinder for the second pressure pin is increased, the piston rod in the cylinder begins to move forward, The force is transmitted to each of the nest stems or the first pressure pin and directly to the second pressure pin through the crosshead, so that the nest stem or the first pressure pin and the second pressure pin are Advance. As a result, the pressing force that acts on the molten metal in the mold cavity is increased, and the molten metal is pressed by the area of the tip of the insert stem and the area of the tip of the pressure pin, forging the molten metal. In this case, the surface pressure by the nesting stem and the pressing pin is large, and a product corresponding to each of them is very precise.

During this pressing operation, since the gate is closed by the center pin, no reaction force is applied to the injection plunger. Therefore, the gate is retracted earlier than the time when the molten metal in the cavity solidifies, and the next operation starts. However, the molten metal does not flow backward and the casting cycle time can be shortened.

Further, since the gas is discharged from the gaps around the insert stem and the pressurizing pin during the filling of the molten metal, defects due to the gas are eliminated. However, when the molten metal is filled and pressurized by the nesting stem and the pressure pin, the reaction force causes the molten metal to enter the gap, cool and solidify, and remain as burrs even when the product is taken out. The burr is removed by advancing and retracting the pin, and the passage is kept gas flowing.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of the apparatus of the present invention, which is shown as a vertical molten metal forging apparatus for manufacturing automobile wheels made of aluminum alloy. In FIG. 1, 1 is a fixed platen that is also a horizontal lower platen, 2 is a lower mold holder, 3 is a fixed mold that is also a lower mold, 4 is a cylinder platen provided above, and 5 is a mold. A mold clamping cylinder for opening the mold, 6 is a piston rod, 7 is a movable platen that moves in the vertical direction, and 8 is a column that connects the fixed plate 1 and the cylinder platen 4. A gate hole 3a having a slightly larger inner diameter is provided downward at the center of the fixed mold 3 axis.

In the central portion of the inner axis of the movable plate 7, there is a downward facing 1
A plurality of large first hydraulic cylinders 9 are incorporated, and one hollow large-diameter piston 10 of the first hydraulic cylinder 9 has a cylindrical lower end in the center or a similar shape. Nesting stem 13 with a shape that fits in the shape range
Is installed. In the lower central part of the movable plate 7, there is a back plate 7a of the movable mold 12 and the movable mold 12, and the cylindrical nesting stem 13 has a through hole 1 in the movable mold 12.
2a is provided slidably in the vertical direction, and its tip end faces the mold cavity 14. The first
The outer diameter of the piston 10 of the hydraulic cylinder 9 is larger than the outer diameter of the insert stem 13, for example, a large diameter close to the outer diameter of the movable mold 12 so that a large pressing force can be applied. Leave.

Further, instead of one nesting stem 13, a plurality of first pressure pins 11 arranged concentrically may be used. In this case, for example, the structure is as shown in FIG. That is, each first pressurizing pin 11 penetrates through the movable mold 12 and can slide in the vertical direction, and the rear end portion is fixed to the front end surface of the piston 10. The tip of each first pressure pin 11 faces the mold cavity 14. In this case, since there is no nesting stem 13, a center pin 18, which will be described later, is attached to the axial center of the movable mold 12 so as to be vertically slidable.

Reference numeral 15 denotes several cores which are a part of the movable mold provided around the movable mold 12. In FIGS. 1 and 2, the core 15 is incorporated in the lower end of the outer periphery of the movable plate 7. The movable core cylinder 16 allows the product to be moved in the horizontal direction, allowing the product to be taken out. Core 15
The outer peripheral portion of the lower end of the core 15 is provided with a tapered surface 15a. When the core 15 is closed and the mold is clamped, the tapered surface 15a is formed.
However, it is adapted to fit with the taper surface 17 a of the inner surface of the taper ring 17 provided on the upper outer periphery of the lower die holder 2.

Reference numeral 18 is a center pin for hot water supply and gate cutting, which is usually called an acurad pin. About half of the tip of the center pin 18 slides in the hole 13a at the axial center of the insert stem 13. It is freely provided, and its front end portion can be moved in and out from the lower end portion of the insert stem 13, and when the center pin 18 projects from the insert stem 13, the gate hole 3a of the fixed mold 3 is provided. It is designed so that it can enter and block it. The rear end portion of the center pin 18 is integrally connected to the piston rod 20 of the cylinder 19 incorporated in the piston rod 6 in the hole of the axial center portion of the piston 10. Inside the center pin 18, a hole for cooling water is provided up to near the tip.

Reference numeral 21 is a casting sleeve attached to the axial center of the fixed platen 1, 22 is a plunger tip provided in the casting sleeve 21 so as to be vertically slidable, 23 is an injection plunger, and 24 is an injection plunger. It is a casting cylinder, and the lower end of the injection plunger 23 is integrally connected to the piston rod 25 of the casting cylinder 24. The casting cylinder 24 is
It may be fixed to the fixed plate 1 via a connecting member,
Normally, it is convenient to be able to vertically move and tilt together with the casting sleeve 21, the plunger tip 22, etc. by a tilting device (not shown). Note that these are known and are commonly used, for example, in Japanese Patent Publication No. 57-21414 and Japanese Patent Publication No. 58-29182.

Near the outer periphery of the movable platen 7, several downward second hydraulic cylinders 47 are incorporated, and a ring-shaped crosshead 49 is provided at the lower end of each piston rod 48 of the hydraulic cylinders 47. A plurality of second pressure pins 50 are mounted on the same circumference below the crosshead 49. The pressure pin 50 is vertically slidably provided in a hole penetrating the movable plate 7 and the movable die 12, and the tip end portion thereof has a mold cavity 1
4 faces a cylindrical end surface portion.

6 to 8 are detailed or operational views of this portion, in which the second pressurizing pin 5 whose tip portion has an opening / closing valve portion.
On the outer peripheral surface of No. 0, several grooves 52 for passing gas are formed in the axial direction except for the tip. The rear portion of the groove 52 is connected to the atmosphere, the vacuum tank 55, or the like by the passage 53 and the electromagnetic switching valve 54 via the hole 52a. 5
6 is a vacuum pump. Further, reference numeral 51 is a seal provided on the outer periphery of the upper portion of the pressure pin 50 to prevent air from entering.

As shown in FIGS. 1 and 3 to 5, a small gap 43 of, for example, about 0.1 to 0.3 mm for passing gas is provided in the lower portion of the through hole 12a, and a passage 44 is formed. It can also be connected to the passage 53 through. With this configuration, the gas in the cavity 14 can be discharged to the outside even from the outer peripheral portion of the tip of the insert stem 13. 45 is an O-ring.

26 is a hydraulic pump, 27 is a relief valve, 4
0 is a four-way switching valve for the mold clamping cylinder 5, 28 is a four-way switching valve for the center pin 18 for feeder and gate cutting, 2
9 is a four-way switching valve for the first hydraulic cylinder 9 for pressurizing the nest pin, 30 is a four-way switching valve for the second hydraulic cylinder 47 for pressurizing the second pressurizing pin 50, 31 is for the core cylinder 16. 4 is a four-way switching valve, 32 is a four-way switching valve for the casting cylinder 24, 41 and 33 to 37 are relief valves, 38 is a check valve, and 39 is a tank.

Next, the operation of the present invention will be described.
First, with the mold open, retract the center pin 18,
With the core 15 advanced, the rod-side chamber 9b of the insertion pin pressurizing cylinder 9 is filled with hydraulic oil to operate hydraulic pressure. Then, the piston 10 goes up, and in this state, the nest stem 13 is retracted relative to the movable mold 12. In this state, the mold clamping cylinder 5 is operated to move the movable platen 7 downward, whereby the movable mold 12, the insert stem 13, and the center pin 18 are simultaneously advanced downward to perform the mold clamping operation.

In the mold clamped state, the lower end tapered surface 15a of the core 15 is fitted to the tapered surface 17a of the taper ring 17, and the lower end surface of the core 15 is in contact with the fixed mold 3 and the upper surface of the lower mold holder 2. ing. As shown in FIG. 1, a mold cavity 14 is formed between the movable mold 12, the fixed mold 3 and the core 15. In this mold clamping state, the mold clamping force from the mold clamping cylinder 5 is applied from the movable platen 7 to the movable mold 1.
2, the core 15, the fixed mold 3, the lower mold holder 2, and the fixed platen 1.

On the other hand, after lowering the casting sleeve 21 and separating it from the stationary platen 1, an unillustrated casting cylinder tilting device is operated to move the casting cylinder 24, the upper portion of the casting sleeve 21 and the like horizontally. Tilted or moved horizontally in the direction to cast the molten metal with a ladle in a place where it does not get in the way 2
Pour in 1 At this time, the plunger tip 22 may be lowered to the lower part of the casting sleeve 21 in advance. It is also possible to prevent air from being entrapped in the molten metal and to prevent the molten metal temperature from decreasing as much as possible.

When the pouring of the molten metal into the pouring sleeve 21 is completed, the pouring cylinder 24 is returned to the vertical state, the pouring sleeve 21 and the like are raised, and as shown in FIG.
1 is docked on the fixed board 1. After performing mold clamping and pouring, the casting cylinder 24 is operated to operate the plunger tip 2
2 is raised and the molten metal 42 is cast into the mold cavity 14. The state in the middle of casting is shown in FIG.

During the casting, the gas is discharged in a vacuum through the passage 53 from the gap 43 in the lower outer periphery of the insert stem 13. Four
4 is an O-ring. The molten metal 42 fills the cavity 14 and also enters the gap 43.
Since it is small, it solidifies by cooling immediately and does not penetrate deep into the entrance.

If the tip of the pressure pin 50 is projected into the cavity 14 during casting, as shown in FIG.
The groove 52 on the outer circumference of the pressure pin 50 communicates with the cavity 14,
The gas is discharged from the groove 52 to the outside through the passage 53.
If it is sucked in a vacuum, its discharge is accelerated. Immediately before the molten metal 42 fills the cavity 14, the second hydraulic cylinder 4
When 7 is actuated to pull up the pressure pin 50, the passage is closed as shown in FIG. 6, and the molten metal 42 does not enter the groove 52. At this time, at the same time, degassing is also performed from the gap 43 on the outer periphery of the insert stem 13.

When the mold cavity 14 is filled with the molten metal, the cylinder 19 for the center pin 18 is actuated by operating the center pin 18 while the casting force is exerted on the molten metal by the action of the casting cylinder 24. Is moved forward so that the tip of the center pin 18 enters the upper end of the gate hole 3a. By the forward movement of the center pin 18, a feeder force is applied to the molten metal 42 in the mold cavity 14. Further, the upper end of the gate hole 3a is closed by the tip of the center pin 18. The state at this time is shown in FIG.

When the gate hole 3a is closed, the four-way switching valve 2
9 is operated to feed the working oil in the chamber 9a on the head end side of the first hydraulic cylinder 9 to move the piston 10 forward, and its force is applied with a simple shape and structure to the cylindrical nesting stem 13
By directly and efficiently applying high pressure to a portion corresponding to the lower side of the insert stem 13, for example, 3 to 4 to
A relatively large surface pressure of n / cm ² is applied, and the solidified molten metal or metal is pressed by concentrated pressure to perform molten metal forging. This is also the case when a plurality of first pressurizing pins 11 are used as shown in FIG. 2 instead of using one nesting stem 13, which results in a machine without a dense nest. Good quality products with high strength can be obtained. This state is shown in FIG.

Further, after the gate hole 3a is closed by the tip of the center pin 18, hydraulic oil is sent to the head end side of the second hydraulic cylinder 47, and the crosshead 49 is advanced through the piston rod 48, and its force is 2 pressure pin 50
To press the metal into the cavity 14, press the tip of the insert stem 13 with less pressure transmission, and forge the molten metal. The timing of pressurization is set according to the coagulation time which varies depending on the thickness of the portion.

On the other hand, when the center pin 18 closes the gate hole 3a, it is not necessary to pressurize the biscuit with the plunger tip 22, so that the molten metal in the cavity is solidified.
The casting cylinder 24 is actuated without the completion of pressure forging.
The casting sleeve 21 and the plunger tip 22 are retracted to shift to the next operation. As a result, the cycle time of the device can be shortened. The pouring sleeve 21 separated from the fixed platen 1 and the fixed mold 3 is tilted together with the pouring cylinder 24, and the upper part of the pouring sleeve 21 is moved to the side of the fixed platen 1 for the next pouring.

Thus, after the pressure forging, that is, the molten metal forging is finished and the product is cooled, a predetermined operation is performed, the center pin 18 is further projected, and the biscuit 46 remaining in the gate of the lower die 3 is cut and attached. Drop it. This state is shown in FIG. Then, after the mold is opened, a product extruding device (not shown) is operated to extrude and take out the product from the movable mold 12. When the product is extruded, the nest stem 13 is also moved forward, so that the burr that has entered the gap 43 can also be pushed down. If the burr is difficult to drop, the burr can be surely cleaned by repeating the forward and backward movements of the insertion stem 13, so that the next degassing can be surely performed. The same applies to the pressure pin 50 side.

In the above embodiment, an example of the vertical clamping vertical casting type is shown, but this is not necessarily limited to the vertical type, and a horizontal clamping type may be used. Further, in the above-mentioned embodiment, the example in which the core 15 is movably attached to the movable mold 12 side which is the upper mold is shown, but in this embodiment, the core 15 is movable to the fixed mold 3 side which is the lower mold. The core may not necessarily be used depending on the type of molten metal forging product to be manufactured. Of course, the present invention can be used not only for manufacturing the aluminum wheel shown in the embodiment but also for manufacturing other products.

[0037]

As described above, according to the present invention, as shown in the claims, the fixed mold attached to the fixed plate and the movable mold attached to the movable plate are provided, and the mold is provided. A center pin that is movable in the opening and closing direction and is arranged around the center pin that opens and closes the gate on the fixed mold side, is slidable in the mold opening and closing direction, and has its tip facing the cavity and for pressurizing the molten metal. In a molten metal forging device in which a plurality of first pressure pins arranged on a movable die side or a concentric circular stem are provided on the movable die side, a cylindrical shape is formed around a center pin located in the central portion of the axis of the movable plate. Since a large-sized first hydraulic cylinder having one piston is provided, and the insert stem or the first pressure pin is directly attached to the end surface of the piston of the first hydraulic cylinder, mold clamping and casting are performed. ， Fill the mold cavity with molten metal Immediately after the operation, due to the action of the nesting stem, etc., the pressing force can be concentrated on the part where strength is required, and the molten metal forging can be performed on that part, and at the same time, the gas on that part is discharged, A large diameter first hydraulic cylinder for pressurizing the nesting stem or the plurality of first pressurizing pins is of course capable of reliably and easily producing a product having a high mechanical strength without a dense cavity. By arranging the cylinder in the center of the movable plate and simplifying the shape and structure, the force flow is smoothed, the force transmission efficiency is improved, and the molten metal is concentrated and pressurized to ensure good quality products. Can be easily obtained.

Further, since the insert stem or the first pressurizing pin is directly attached to the first hydraulic cylinder,
Unlike the conventional device, it is not necessary to connect the insert stem or the like to the insert stem driving cylinder via the crosshead, and the movable plate can be made smaller.

Further, by arranging the first hydraulic cylinder for pressurizing the telescopic stem in the center, a space is created in the periphery, and the second hydraulic cylinder for the second pressurizing pin for pressurizing the outer circumference of the cylinder is provided therein. It becomes possible to arrange. Then, a plurality of second hydraulic cylinders are concentrically arranged inside the movable plate, and a ring-shaped crosshead is connected to the tip end portion of each piston rod of the second hydraulic cylinder, and the cylindrical end surface portion of the cavity is connected. Since a plurality of second pressure pins provided with the tips facing each other are attached to the crosshead, pressure can be applied even on the outer peripheral portion of the product, and a denser product with even better riser can be obtained. be able to.

Further, the tip of the second pressure pin is used as an opening / closing valve, and a groove extending in the axial direction is provided on the outer peripheral surface of the second pressure pin leaving the tip, and a gas is provided behind the groove. Since the venting device is connected, it is possible to easily discharge the gas in the upper peripheral portion where the gas in the cavity is most likely to be accumulated by using the second pressurizing pin. Therefore, by the action of the second pressurizing pin, it is possible to perform both the riser action and the gas discharge action, there is no gas entrainment, and there is no sinkhole due to the pressurization, so that a product with high strength can be reliably and easily produced. Can be obtained.

Immediately after the molten metal is poured into the cavity, the tip of the center pin, which is slidably provided on the inner axial center of the insert stem, is provided in the fixed mold. Before the molten metal forging ends because the injection plunger can be retracted between the time when the gate is closed and the end of the molten metal forging due to the advancement of the insert stem etc. By closing the gate with the center pin, the casting sleeve and plunger can be moved to the next operation quickly, and as a result, the casting cycle can be shortened and productivity can be improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a second embodiment of the present invention,
An example in which the first pressure pin is used instead of the nesting stem is shown.

FIG. 3 is a vertical cross-sectional view showing an operating state during filling in one embodiment of the present invention.

FIG. 4 is a gate cut after filling in one embodiment of the present invention,
It is a longitudinal cross-sectional view showing an operating state at the time of sealing.

FIG. 5 is a vertical cross-sectional view showing an operating state when a biscuit is cut in one example of the present invention.

FIG. 6 is a vertical cross-sectional view showing an operating state of the second pressure pin immediately after filling in one embodiment of the present invention.

FIG. 7 is a vertical cross-sectional view showing an operating state of the pressurizing pin when gas is being discharged during casting in one embodiment of the present invention.

8 is a cross-sectional view taken along the line AA of FIG.

[Explanation of symbols]

 1 Fixed Plate 3 Fixed Mold 3a Gate Hole 4 Cylinder Platen 5 Mold Clamping Cylinder 7 Movable Plate 8 Column 9 First Hydraulic Cylinder 10 Piston 11 First Pressure Pin 12 Movable Mold 13 Nested Stem 14 Mold Cavity 15 Core 16 Core cylinder 17 Taper ring 18 Center pin 19 Cylinder 21 Casting sleeve 22 Plunger tip 23 Injection plunger 24 Casting cylinder 26 Hydraulic pump 28-32, 40 Four-way switching valve 42 Molten metal 43 Gap 44, 53 Passage 47 Second hydraulic pressure Cylinder 49 Crosshead 50 Second pressurizing pin 52 Groove 54 Electromagnetic switching valve 55 Vacuum tank 56 Vacuum pump

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location B22D 17/22 G 27/11

Claims (3)

[Claims] 1. A center pin and a center pin, which are provided with a fixed mold attached to a fixed plate and a movable mold attached to a movable plate, are movable in a mold opening / closing direction and open / close a gate on the fixed mold side. A plurality of first pressurizations arranged on a cylindrical nesting stem for concentrating the melt or concentric circles, which is arranged around the periphery of the mold, is slidable in the mold opening / closing direction, and has a tip end facing the cavity. In a molten metal forging device in which a pin is provided on a movable die side, a large-sized first fork having one cylindrical piston around a center pin located at a central portion of an axis of a movable platen.
And a first pressurizing pin is directly attached to the end surface of the piston of the first hydraulic cylinder. 2. A plurality of second hydraulic cylinders are concentrically arranged inside a movable plate, and a ring-shaped crosshead is connected to the tip of each piston rod of the second hydraulic cylinder to form a cylindrical cavity. The molten metal forging device according to claim 1, wherein a plurality of second pressure pins provided with the tip end facing the end face portion are attached to the crosshead. 3. An opening / closing valve is provided at the tip of the second pressure pin, and an axially extending groove is provided on the outer peripheral surface of the second pressure pin leaving the tip and a gas is provided behind the groove. The molten metal forging device according to claim 2, wherein a drawing device is connected.