KR100670187B1 - Pressure type casting process and mold using press - Google Patents

Abstract

A multistage pressing-type die casting method using a press and a mold thereof are provided to easily replace only molds according to shapes and sizes of the product by using the mechanical press. A multistage pressing-type die casting method using a press is composed of injecting a liquid metal material in the cavity of upper and lower molds(2a,3a) through gravity by using a mechanical press(1); a step of lowering the upper mold, combining the upper mold with the lower mold, and pressing the metal material injected in the cavity of the lower mold through the power of the mechanical press; and a step of pressing the metal material filled in the cavity of the lower mold by using hydraulic pressure cylinders(4a,4b). The liquid metal material is injected in the cavity by using the gravity from the upper side of the upper mold.

Description

Press type casting process and mold using press

1 and 2 are a front view and a side view of an embodiment equipped with upper and lower molds to illustrate the present invention.

Figure 3 (a) (b) is an embodiment of the pressure-down die-casting method of casting the injection of the liquid material in a state in which the upper and lower molds of the present invention combined or separated.

4 to 7 is an operating state diagram of the embodiment.

Figure 8 (a) (b) is a comparison drawing for comparing the die casting mold of the present invention and the prior art.

9 to 12 is an exemplary operation state of the pressure-up die casting method for casting the liquid material injected into the upper, lower mold of the present invention.

Figure 13 is a press front view of a mold closed die casting method embodiment of the present invention.

14 and 15 are operational state diagrams of the embodiment.

Figure 16 is a front view of the press of the die left and right die casting method of the present invention embodiment.

17 to 22 are operating state diagrams of the embodiment.

Figure 23 is a graph comparing the time and temperature of the ultra-high pressure die casting method and the general die casting method of the present invention.

※ Explanation of code for main part of drawing

1: press 11: body

12: drive motor 13: flywheel

14: crankshaft 15: crank rod

16 ball joint 17 upper platen

18: lower platen 2a, 2b, 2c: upper mold

21: pressure hole 22: locking groove

23: wedge portion 3a, 3b, 3c: lower mold

31: pressurization hole 32: wedge

33: slide guide plate 34a, 34b: cylinder for horizontal movement

35: inclined portion 4a, 4b: upper, lower hydraulic cylinder

41a, 41b: upper and lower plunger 42a, 42b: upper and lower plunger tip

43b: eject pin 44a, 45a: upper presser protrusion

45b: lower pressurization protrusion 46b: control tool

5: accumulator 51: accumulator cylinder

6: cylinder for closing mold

The present invention relates to a die-casting method and a mold that enables the casting of a liquid state material at a high pressure using a mechanical press. The method of the present invention is a liquid state by mounting a hydraulic apparatus on a press having a crankshaft applied to a forging method. Die-casting method and mold that can produce molded products with excellent mechanical properties with shrinkage holes and compact structure by injecting metal material of gravity into mold cavity using gravity and then pressurizing with hydraulic device and plastic deformation. It is to provide.

In general, the die casting product has a disadvantage in that the solidification time is long because the casting of the liquid metal (aluminum) material is performed at the liquidus temperature or higher, and casting defects are generated accordingly, so that the mechanical properties are low. Therefore, there is a demand for a casting method capable of removing shrinkage generated during solidification.

Existing equipment for forming a product using a liquid metal material, that is, die casting or squeeze casting is difficult to form a product having excellent mechanical properties.

Conventional die casting or squeeze casting equipment has a low pressure on the liquid metal material injected into the cavity of the mold, mainly by pressing horizontally or in the bottom. Therefore, it becomes difficult to remove defects such as shrinkage holes generated in the thick portion locally inside the molded product. And since the pressure applied in high pressure squeeze casting was limited up to about 150 MPa, it was practically difficult to eliminate shrinkage defects.

Therefore, the present invention was created in order to solve various problems appearing in the prior art, and an object of the present invention is to eliminate shrinkage defects generated in casting, and to melt and add structural alloys as well as general casting alloys into molds. Ultra-high pressure multi-stage pressure type to control molding speed, molding pressure and molding time by continuously pressurizing even after complete solidification of product to remove casting defects such as shrinkage or bubble hole and to make molded products with excellent mechanical properties. It is to provide a die casting method.

Another object of the present invention is to provide an ultra-high pressure die-casting method capable of maintaining pressurization after molding, which is impossible in conventional presses, so that it can be applied to a process requiring pressurization during the solidification time of a liquid metal material. In addition, it is possible to remove defects such as shrinkage holes by applying pressure even after solidification, and to obtain a product having excellent mechanical properties with a finer microstructure.

Still another object of the present invention is to provide a plunger mounted on an upper platen by injecting a liquid metal material using gravity in a closed (bonded) state or a heat-opened (separated state) in which the upper mold and the lower mold are closed. By providing a die casting method and apparatus that can be pressurized with a Plunger, it can provide less cycle defects, better mechanical properties, and shorter cycle times than conventional squeeze casting, low pressure casting and gravity casting.

It is still another object of the present invention to provide a die casting mold capable of simultaneously forming a plurality of products by forming a plurality of cavities horizontally radially in a mold.

Still another object of the present invention is to lower the plunger of the upper platen in a closed state (closed) of the upper mold and the lower mold, and to pressurize the liquid metal material injected into the cavity in the lower mold. The pressurized cylinder is raised from the bottom to provide a pressurized die-casting method for forming a product by pressing the first pressurized material secondly.

Still another object of the present invention is to provide a closed die casting method for casting a product by injecting a liquid metal material into a lower mold and directly pressing the material with the upper mold in a mold (separated) state in which the upper mold and the lower mold are opened. Thus, compared with the existing cold forging and hot forging, it provides the advantage of low molding load, excellent filling and extending the life of the mold.

Still another object of the present invention is to provide a clamping force maintenance structure that enables the upper mold to maintain the clamping force when the upper mold is molded into the lower mold.

Still another object of the present invention is to provide a die casting method having excellent mold force by allowing a top mold to wrap a lower mold formed by separating a left and right type by modifying a general mechanical press.

The present invention as a means for achieving the above object,

Injecting a liquid metal material into the cavity of the upper and lower molds mounted on a general mechanical press using gravity;

Mechanically pressing a metal material which is solidified by being injected into the cavity of the mold by simultaneously lowering the upper mold mounted on the upper platen bottom of the mechanical press to form a lower mold operation;

After the mechanical pressing step of the upper mold, the hydraulic operation of the upper hydraulic cylinder mounted on the upper platen continuously causes the upper plunger to press the metal material which is solidifying in the mold cavity for a predetermined time, so that the metal material is inside the cavity. Casting to plastically deform in a state filled with the same pressure throughout;

The product is cast in the cavity is characterized in that the molded into a dense structure.

In addition, the liquid metal material is injected into the cavity using gravity from the upper side of the upper mold in the state that the upper and lower molds are combined (bonded) or the cavity of the lower mold in the state of the upper and lower molds opened (separated). It is characterized by injecting in.

In addition, the upper and lower plungers are moved into the upper and lower plungers by hydraulic operation of the upper hydraulic cylinder mounted on the upper platen and the lower hydraulic cylinder mounted on the lower platen. It is characterized by casting the product by pressing for a certain time at the same time from the lower side.

In addition, after pressing the metal material injected into the cavity in the state in which the upper and lower molds are combined with the upper plunger of the upper hydraulic cylinder, the lower plunger rises by the operation of the lower hydraulic cylinder to press the metal material to cast the product. It is characterized by molding.

In addition, the upper and lower molds, the upper mold is joined to the lower mold by holding the upper mold coupled to the lower mold by the wedge moving toward the mold by the appearance of the piston rod of the cylinder for closing the mold during the upper platen lowering operation. It is characterized in that the clamping force is maintained.

In addition, the liquid metal material is injected into the cavity formed in the lower mold is characterized in that the product is cast molded in the cavity of the lower mold by the pressing force by the lowering operation of the upper plunger.

In addition, the cavity of the mold is formed only on the lower mold formed of the left and right split molds coupled and separated to the left and right, the inner surface of the upper mold inclined surface formed on the outer periphery of the left and right split molds of the lower mold formed during the lower operation It is characterized in that the pressure inclined surface is formed to maintain the molded clamping force while wrapping the.

And, the die casting mold is characterized in that the cavity is formed so that a plurality of horizontal radially around the center by a plurality of runner parts connected horizontally at a predetermined angle to the center of the metal material is injected.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 and 2 are a front view and a side view of an embodiment provided with upper and lower molds for explaining the present invention, Figure 3 (a) (b) is combined or separated the upper and lower molds of the present invention The pressure drop die casting method is an embodiment in which the liquid material is injected in the state cast, Figures 4 to 7 is an operating state diagram of the embodiment, Figure 8 (a) (b) compares the die casting mold of the present invention and the prior art 9 to 12 is an exemplary operation state diagram of an upward pressure die casting method for casting a liquid material injected into the upper and lower molds of the present invention, Figure 13 is a press of the die closed die casting method embodiment of the present invention 14 and 15 are operational state diagrams of the above embodiment, FIG. 16 is a press front view of an embodiment of the mold left-right separation die casting method of the present invention, and FIGS. 17 to 22 are the seals. The example operating state diagram, Figure 23 shows a comparison of the ultra-high pressure die casting process and the time and temperature of the plain die casting method of the present invention graph.

1 and 2 of the drawings to show that the present invention is applied to a general mechanical press 1, the press 1 is a main body 11, a drive motor 12 which is a power source installed on the upper end thereof, A flywheel 13 which is rotated by the power of the drive motor, a crankshaft 14 rotating together with the flywheel, a crank rod 15 for converting the rotational movement of the crankshaft into a linear motion, and the crank A ball joint 16 formed at the free end of the rod, an upper platen 17 connected to the ball joint for reciprocating up and down, and a lower platen fixed to the lower side of the main body 11. It is comprised by the tongue 17.

The present invention is characterized in that the upper and lower molds 2a and 3a are formed in the mechanical press 1 configured as described above to form a die casting product using a liquid metal (aluminum alloy or copper alloy) material. In addition, the liquid metal material is gravity-injected into the cavity (not shown) formed to mold the product inside the upper and lower molds, and the metal material is pressurized even during the process of solidifying the liquid metal material after the injection. As a result, the shrinkage hole defect caused by the shrinkage phenomenon that occurs when the metal material is cooled or the bubble defect caused by the air existing in the cavity are excluded, and the molding is formed into a dense structure in the cavity inside the upper and lower molds. It is to provide a method to make it possible.

To this end, the press 1 is provided with upper and lower molds 2a and 3a in which a cavity for casting a die casting product is formed as a liquid metal material.

Each embodiment for casting the product according to the shape, shape and specification of the die casting product (hereinafter abbreviated as 'product') to the upper and lower molds (2a) (3a) will be described.

1 and 2, the upper hydraulic cylinder 4a is installed at the center of the upper surface of the upper platen 17 of the press 1, and the upper plunger 41a of the upper hydraulic cylinder is It is configured to reciprocate vertically through the center of the platen 17 downward.

The upper plunger tip 42a is mounted at the lower end of the upper plunger 41a. The upper plunger tip 42a reciprocates the inside of the pressing hole 21 formed at the center of the upper mold 2a up and down. It is formed to move and is configured to press the liquid metal material injected into the cavity of the lower mold.

In addition, a plurality of accumulator cylinders 51 provided with accumulators 5 around the upper platen 17 penetrate each of its piston rods 52 downward through the periphery of the upper platen 17. The accumulator 5 stores the hydraulic pressure supplied from the hydraulic pump (not shown) installed in the press 1 and operates the accumulator cylinder 51. That is, the accumulator 5 sends the hydraulic pressure to the accumulator cylinder 51 by the compression and expansion action of the gas to lower the upper mold 2a at a high speed and to form the lower mold 3a. Thereafter, the upper hydraulic cylinder 4a presses the upper mold 2a by using the hydraulic pressure supplied from the hydraulic pump to pressurize the metal material injected into the cavity of the lower mold 3a to ultra high pressure.

In addition, a plurality of mold closing cylinders 6 are installed at the periphery of the upper platen 17, and the piston rod 61 of the cylinder 6 also passes downward through the periphery of the upper platen 17. The upper mold 2a is lowered by being operated so that the wedge 32 of the lower mold 3a is fitted into the locking groove 22 formed at the lower circumference of the upper mold 2a as described below. The clamping force which maintains the state joined to the metal mold | die 3a is produced.

The lower mold 3a is installed on the upper surface of the lower platen 18 of the press 1, and the wedge 32 is provided with a hole 32a inclined at one surface at an upper circumference of the lower mold. Is formed, and a lower hydraulic cylinder 4b is installed at the bottom of the lower platen 18, and the lower plunger 41b of the lower hydraulic cylinder penetrates through the center of the lower platen 18. And a lower plunger tip 42b mounted on the upper end of the lower plunger 41b to reciprocate vertically toward the inner side of the lower die 3a. It is inserted and installed as possible to support the liquid metal material injected into the cavity of the lower mold 3a, or is configured to press the liquid metal material injected into the cavity upward from the lower side.

Injecting the liquid metal material into the cavity of the upper and lower molds (2a) and (3a) of the press (1), such as the conventional die casting or squeeze casting, and forcedly injected into the cavity at a high pressure and high speed. Unlike the method to make the liquid metal material into the cavity of the mold by using gravity, the upper platen 17 is lowered, and then by lowering the upper plunger 41a by hydraulic operation of the upper hydraulic cylinder (4a) The product is molded by casting the plastic material so that the metal material is filled at the same pressure in the cavity at a constant pressure, so that the operation of pressurizing the metal material which is being injected into the cavity of the cavity is maintained for a predetermined time. .

Each embodiment of the casting method according to molding the product as described above will be described with reference to the drawings.

FIG. 3 (a) shows the piston rod 52 of the accumulator cylinder 51, which is activated (advanced) to operate the liquid metal material inside the cavity in a state where the upper mold 2a is formed on the lower mold 3a. As shown in the embodiment using a gravity to the injection, the liquid metal is injected into the cavity through the pressure hole 21 of the upper mold (2a) in the state in which the upper and lower molds (2a, 3a) are combined The injection amount of the material is slightly smaller than the amount injected into the entire cavity of the lower mold 3a (it varies depending on the product to be molded, but it is filled in the range of about 70 to 90% of the cavity space on average) As shown in the figure, even though the liquid metal material is filled in a smaller amount than the cavity space of the lower mold 3a, the upper mold has the same horizontal surface as the upper surface of the metal material filled in the cavity of the lower mold 3a. (2a) pressure hole (21) This is because a metal material is injected into the lower side, and the metal material injected into the lower side of the press hole 21 of the upper mold flows into the cavity during pressurization, so that the metal material moves in the cavity. Press-filled to have a dense structure to enable the product to be cast.

When the press 1 is operated after injecting a liquid metal material into the cavities of the upper and lower molds 2a and 3a formed as described above, the crankshaft 14 rotates and the crank rod 15 is rotated. The lowering operation is started. As shown in FIG. 4, the lower end of the piston rod 61 of the mold closing cylinder 6 is a hole of the wedge 32 as a state before the crankshaft 14 reaches the bottom dead center. Until the upper mold 2a enters 32a), the upper mold 2a remains in a state of being joined with the lower mold 3a by its own weight, and the crankshaft 14 is positioned at the bottom dead center position as shown in FIG. When reaching, the mold closing cylinder 61 is operated to show the piston rod 61 so that its inclined lower end enters the hole 32a of the wedge 32 and moves the wedge 32 toward the upper mold 2. By being pushed out, the wedge 32 is caught in the locking groove 22 formed at the lower end of the upper mold 2a. As described above, when the wedge 32 is caught in the engaging groove 22 of the upper mold 2a, the upper mold 2a generates a clamp force that is maintained in the state of being joined to the lower mold 3, as will be described later. When the upper plunger tip 42a flows into the cavity by applying a pressing force to the metal material filled in the lower end of the pressure hole 21, the upper mold 2a does not occur in the lower mold 3a.

On the other hand, in the state in which the crankshaft 14 reaches the bottom dead center as described above, the driving motor 12 is stopped for a predetermined time, and at this time, the lowering operation of the upper platen 17 is completed, the upper hydraulic pressure Although the upper plunger 41a and the upper plunger tip 42a of the cylinder 4a enter the inside of the pressing hole 21 of the upper mold 2a, the upper plunger tip 42a is still the pressing hole 21. When the metal material charged in the lower side is not pressurized (refer to FIG. 5), and when the upper platen 17 has completed the lowering operation as described above, the upper hydraulic cylinder 4a is operated to operate the upper plunger 41a. The lower plunger tip 42a presses the metal material filled in the lower end of the pressure hole 21 (see FIG. 6).

As described above, when the upper plunger tip 42a presses the metal material filled in the pressure hole 21 by the operation of the upper hydraulic cylinder 4a, the liquid metal material is cooled during the cooling operation after being injected into the cavity. Since the solidification is in progress, but plastic deformation is still possible, the pressing hole 21 of the upper mold 2a is pressed by the pressing force of the upper plunger tip 42a which is lowered by the operation of the upper hydraulic cylinder 4a. The metal material that has been filled on the lower side flows into the cavity and is filled in the entire cavity. In this case, the descending distance of the upper plunger tip 42a, which is lowered while pressurizing the metal material, is a shrinkage coefficient that appears when the metal material solidifies. In consideration of this, the entire metal inside the cavity is lowered to a distance that can be cast in a state filled with a uniform pressure. Therefore, the shrinkage hole defects and the air bubble defects caused by the air present in the cavity can be eliminated and the molded product can be molded into a dense structure.

7 is a view illustrating demoulding the molded product after the casting of the product is completed in the cavity by the pressurization operation of the metal material by the operation of the upper hydraulic cylinder 4a, in which case the drive motor 12 is again The crankshaft 14 is rotated to the top dead center position by driving. Before the operation of the crankshaft 14 is rotated upward, the cylinder for closing the mold 6 is operated to start the piston rod 61. When immersed (reversed or raised), the lower end of the piston rod 61 is relaxed in the hole 32a of the wedge 32, whereby the wedge 32 has its own elastic force (elastic restoring force by torsion spring, etc.). It is separated from the locking groove 22 of the upper mold and returned to its original position. Then, the upper mold 2a together with the upper platen 17 is operated upward.

When the upper mold 2a is raised in the above, the finished product remains inside the cavity of the lower mold 3a. Because the casting finished product has a larger contact area with the cavity of the lower mold 3a than the contact area with the cavity of the upper mold 2a, and the weight of the product is acting as the lower mold 3a. When 2a) is raised, the cast product remains in contact with the cavity of the lower mold 3a, and immediately after the ascending operation of the upper mold 2a is completed, the lower hydraulic cylinder 4b is operated to raise the upper portion. When the casted product is raised by lifting the plunger 41b in the cavity of the lower mold 3a and simultaneously lifted upward, the ejection robot mechanism (not shown) takes out the molded product above the lower mold 3a. .

Next, Figure 3 (b) is a method of casting the product by injecting the liquid metal material to the cavity of the lower mold (3a) by gravity in a state in which the upper mold (2a) is separated from the lower mold (3a) In this embodiment, the liquid metal material injected into the cavity of the lower mold 3a using gravity is not filled in the entire space of the cavity, and as described above, with respect to the entire cavity of the lower mold. In the state of being injected to be filled in approximately 70 to 90% of the casting state, the casting of the liquid metal material in the 70 to 90% of the cavity of the lower mold (3a) immediately after filling the accumulator (5) and When the accumulator cylinder 51 operates and the piston rod 52 emerges (advances or descends), the upper mold 2a descends to press the liquid metal material filled in the cavity of the lower mold 3a. It is combined with the sub mold 3a, in which a part of the liquid metal material filled in the cavity of the lower mold is introduced into a state at a suitable height below the pressure hole 21 of the upper mold 2a (Fig. 4). In the following step-by-step operation, as described in the above-described embodiment, the product is molded by a method of casting and then demolding and taking out the metal material by a method of hydraulically pressing the metal material by the operation of the upper hydraulic cylinder 4a.

8 (a) shows upper and lower molds (2a) and (3a) in order to be able to cast and mold a plurality of die casting products by one press casting using a general mechanical press 1 as in the present invention. Each has a structure in which a plurality of cavities are formed radially toward the horizontal direction while maintaining a constant angle with respect to the center portion for injecting the metal material. Therefore, when the upper plunger tip 42a presses the metal material in the plurality of cavity centers, the pressing force acts equally on the entire interior of each of the radially formed cavities, and at the same time, the front side of each cavity The pressing force acts uniformly from the rear side (the end of each cavity) to the back side (the end of each cavity), so that the entire product can be molded into a dense structure without contraction or bubble bonding.

However, as shown in FIG. 8B, a plurality of cavities are formed vertically in the stationary mold and the movable mold, and each of the plurality of cavities connects a sleeve formed at the bottom of the stationary mold side. When the length of the runner part is different, the pressing force of the liquid metal material injected into each of the cavities by the piston is not uniform, and the pressure and time applied to the metal material injected into each cavity connected to the runner part are uniform. There is a problem that the failure rate is high.

Therefore, the method of casting a die casting product using a general mechanical press (1) as in the present invention is a new method that can not be compared with the existing die casting method, it is possible to improve the productivity of die casting products, casting or structural aluminum alloy Of course, non-ferrous metal alloys such as copper alloys as a material has the feature that enables the die casting.

9 to 12 are views showing an embodiment of the rising pressure method, the above embodiment is also cast in a state in which the liquid metal material is injected into the cavity of the lower mold (3a) within a range of 70 to 90%. . It will be described below with reference to the drawings.

9 shows the liquid metal material injected into the cavity of the lower mold 3a while being joined to the lower mold 3a by lowering the upper mold 2a while the crankshaft 14 is at the top dead center. As the primary joining state, at this time, the metal material injected into the cavity is in a liquid state, so that a part of the metal material is introduced into the pressing hole 21 of the upper mold 2a.

Subsequently, when the crankshaft 14 rotates to the bottom dead center position as shown in FIG. 10, when the upper platen 17 and the upper hydraulic cylinder 4a are lowered together, the upper plunger tip 42a at the bottom of the upper plunger 41a is shown. ) Secondary to pressurize the metal material flowing into the upper side of the pressing hole 21 of the upper mold, and at the same time the lower end of the piston rod 61 of the cylinder for closing the mold (6) 32a) to fit the wedge 32 into the locking groove 22 formed at the bottom of the upper mold (2a). In this way, when the wedge 32 is coupled to the locking groove 22 of the upper mold 2a, which is joined to the lower mold 3, the upper mold 2a has a clamping force to maintain the state of mating with the lower mold 3a. do.

As soon as the above operation is completed, the lower hydraulic cylinder 4b is operated to raise the lower plunger 41b as shown in FIG. 11, and accordingly, the lower mold 3a is operated by the upward operation of the upper plunger tip 42b. By pressing the metal material filled in the upper side of the joining hole 31 of the third to upward, that is, to push up into the cavity, wherein the upper side of the upper plunger tip 42a of the pressing hole 31 of the lower mold (3a) In the second pressurization, there is a sufficient amount of metal material to fill the empty space inside the cavity. Therefore, when the lower plunger tip 42b is subjected to the upward pressurization of the metal material, which is filled in the upper side of the press hole 31 of the lower mold, in the third cavity, the inside of the cavity is filled with a full metal material. Since the rising pressure of the lower plunger tip 42b for pressurizing and pressing the metal material in the pressing hole 31 of the mold 3a is equally transmitted to the end of the cavity, each product cast from the plurality of cavities has a shrinkage hole defect. The back is removed and brought into a compact structure.

As shown in FIG. 12, the metal material is cast into a dense structure inside the cavity by the upward pressure operation of the upper plunger tip 42b in the pressure hole 31 of the lower mold 3a by the operation of the lower hydraulic cylinder 4b. In this case, the mold closing cylinder 6 is operated to relax the lower end of the piston rod 61 in the hole 32a of the wedge 32. 32 is released from the locking groove 22 of the upper mold 2a by elastic restoring force such as a torsion spring (not shown) to allow the mold opening operation of the upper mold 2a, and then the crankshaft 14 rotates. When the upper mold 2a starts to be lifted from the lower mold 3a as it is being operated, the lower hydraulic cylinder 4b raises the upper plunger 41b at the same time, so that the angles cast inside the plurality of cavities Products have upper plunger tip (42 By the upward operation of b), the cavity of the lower mold 3a is relaxed and maintained in contact with the cavity of the upper mold 2a, so that each product is raised with the upper mold 2a that is raised. When the crankshaft 14 reaches the top dead center as shown in the drawing, when the upper hydraulic cylinder 4a operates to lower the upper plunger 41a, the upper plunger tip 42a has the upper mold 2a ascending and moving. The product is pushed downward in position to demould.

As described above, when the upper mold 2a demolds the product at the position where the ascending movement is completed, it can be taken out by holding the product by an automatic ejection mechanism such as a robot arm as well as by the automatic ejection mechanism of plate shape. Since the product can be taken out from the bottom, the automatic take-out device of the product can be manufactured with a simple structure.

Next, FIGS. 13 to 15 show an example of a die-closed die casting method, which also uses a mechanical press 1, with the same name and the same reference numerals for the same components as the above-described embodiment. In addition, the description of the same components will be omitted, and only the structural features of the components having a structure different from the above embodiments will be described.

Unlike this embodiment, the upper mold 2b is mounted at the lower end of the upper plunger 41a of the upper hydraulic cylinder 4a, and also pressurized a metal material at the lower end of the upper mold 2b. The upper pressurizing protrusion 44a is formed to protrude.

In addition, the lower mold 3b has a cavity for casting a product with only an upper portion of the cavity opened and closed in all directions, and a lower portion of the lower mold 3b has a lower hydraulic cylinder 4b installed at the bottom of the lower platen 18. It is formed in a structure that is closed by the eject pin (43b).

In the state in which the crankshaft 14 is rotated to a top dead center position as shown in FIG. 13, the upper mold 2b is moved up and the cavity of the lower mold 3b is opened at the upper part. Therefore, as shown in the figure, the liquid metal material is injected by gravity from the upper side of the cavity of the lower mold, wherein the injection amount of the liquid metal material is injected into a predetermined amount with respect to the volume of the product to be molded.

When the injection of the liquid metal material into the lower mold 3b is completed as described above, when the driving motor 12 is driven to move the crankshaft 14 to the bottom dead center, the driving motor 12 stops for a predetermined time. When the crankshaft 14 is moved to the bottom dead center position, the upper mold 2b lowered together with the upper platen 17 enters the upper part of the cavity of the lower mold 3b as shown in FIG. Thus, the upper pressurizing protrusion 44a primarily presses the liquid metal material by mechanical pressure, and then the upper hydraulic cylinder 4a installed on the upper surface of the upper platen 17 operates as shown in FIG. When the plunger 41a is lowered, the upper mold 2b presses the liquid metal material injected into the cavity of the lower mold 3b at the pressure of hydraulic pressure, whereby the metal material is hydraulically pressed. Upper mold at the time of secondary press (2b) The pressing force is pressurized to an ultra high pressure of 175 MPa or more, and this pressurization operation is performed until the final solidification is made to meet the size of the product to be molded into the metal material filled in the cavity of the lower mold 3b. The metal material to be cast is cast in a dense structure without generating shrinkage defects.

As described above, when the operation of pressurizing the metal material secondaryly by the upper mold 2b is completed, the drive motor 12 of the press 1 is driven again to move the crankshaft 14 to the top dead center position. When the upper hydraulic cylinder 4a is operated at the same time and the upper mold 2b is moved upward, the cavity of the lower mold 3b can demold the finished product, and the demolding of the product is performed by the lower hydraulic cylinder 4b. When the) is operated to raise the eject pin 43b, the product is demolded above the lower mold 3b, and thus the demolded product is taken out by the automatic ejection mechanism.

Next, 16 to 22 is an embodiment showing a mold left and right separation die casting method, this embodiment also uses a mechanical press (1). In the drawings of this embodiment, the same components and the same reference numerals are used for the same components as the above-described embodiments, and the description of the same components is omitted, and structural elements of the components having a structure different from the above-described embodiments are omitted. Only the features will be described.

16 shows a structure of an embodiment of a mold left-right separation die casting method, and as shown in the drawing, a plurality of accumulator cylinders installed around the upper platen 17 of the press 1 ( 51) An upper mold 2c is attached to a lower end of each piston rod 52, and a lower mold 3c is provided on an upper surface of the lower platen 18.

The upper mold 2c is formed with a wedge portion 23 formed as an inclined surface gradually extending downward while penetrating through a diameter capable of wrapping the outer circumference of the lower mold 3c.

The lower mold 3c is formed of left and right divided molds 3c-1 and 3c-2 divided into left and right, and each of the left and right divided molds can cast a product to be molded. The cavity is divided to form a cavity in which a product can be cast at the time of molding (bonding).

The left and right split molds 3c-1 and 3c-2 are configured to be separated or coupled to the left and right sides along the slide guide plate 33 fixed to the upper surface of the lower platen 18. (See FIG. 22), and the separation or coupling operation of the left and right split molds is performed by horizontally moving cylinders 34a and 34b horizontally fixed to both upper surfaces of the lower platen 18. That is, the front end of each of the piston rods 34a and 34b of the above-described horizontal movement cylinders 34a and 34b is connected to the left and right split molds 3c-1 and 3c-2, respectively. The right split molds are combined or separated from each other.

In addition, the upper surface of each of the left and right divided molds 3c-1 and 3c-2 has an inclined portion 35 inclined at the same inclination angle as the inclined wedge portion 23 of the upper mold 2c. When the upper mold 2c descends while the right split molds 3c-1 and 3c-2 are joined (coupled), the wedge part 23 is coupled to both inclined portions 35, and the left and right split molds are combined. (3c-1) and (3c-2) generate a clamping force that maintains the integrated state.

In addition, an upper pressurizing protrusion 44a is formed at the lower end of the upper plunger 41a of the upper hydraulic cylinder 4a to pressurize the metal material from above, and is mounted at the end of the lower plunger 41b of the lower hydraulic cylinder 4b. On the upper end of the lower plunger tip 42b, a lower pressurizing protrusion 45b is formed to press the metal material from the lower side.

The lower plunger tip 42b enters into the cavity when the left and right split molds 3c-1 and 3c-2 are joined to each other at the central portion of the slide guide 33. , Only the lower pressing protrusion 45b enters into the cavity, and a control tool 46b is formed to protrude the metal material.

The operation state according to casting and molding the product as the upper and lower molds 2c and 3c configured as described above will be described.

First, as shown in FIG. 17, the left and right divided molds 3c-1 and 3c-2, which are separated on both sides, are operated at the same time by operating both side horizontal moving cylinders 34a and 34b, respectively. ) 3c-2, and the lower hydraulic cylinder 4b is operated so that the lower pressing protrusion 45b formed at the upper end of the upper plunger tip 43b enters the inside of the cavity through the control port 46b. In this state (see FIG. 18), the liquid metal material is injected by gravity, and the injection amount is injected in advance to measure the product to be molded into a dense structure.

18 shows that the crankshaft 14 is coupled in a state in which the upper mold 2c descends and surrounds the molded lower mold 3c before the crankshaft 14 reaches the bottom dead center position. The upper mold 2c lowered to surround 3c has an inclined wedge portion 23 engaged with the inclined portion 35 of each of the divided molds 3c-1 and 3c-2 on both sides of the lower mold 3c. Since the clamping force of the lower mold 3c is maintained, the divided molds 3c-1 and 3c-2 are relaxed when pressing the metal material injected into the cavity of the lower mold 3c as described below. Will not occur.

19 shows when the upper hydraulic cylinder 4a is operated while the crankshaft 14 is rotated to the bottom dead center position. Thus, the upper hydraulic cylinder 4a is operated so that the upper plunger 41a is operated. When lowering the upper pressing projection (45a) formed at the bottom of the lower mold (3c) to enter the cavity to press the metal material hydraulically, this pressurization operation is continued during the time the metal material is solidified in the cavity. Since the pressing force of the upper pressing projection (45a) is evenly transmitted to the entire inside of the cavity. Thus, the product cast inside the cavity is one in which the shrinkage cavity bonds seen in the prior art are removed and molded into dense tissue.

20 shows demoulding the finished product in the lower mold 3c, where the crankshaft 14 is rotated to the top dead center position, and also the piston rod 52 of the accumulator cylinder 51. When the upper mold (2c) is separated from the lower mold (3c) upward by the upward operation and then both horizontal movement cylinders (34a) and (34b) are operated to immerse (reverse) the piston rod of the lower mold (3c). Left and right split mold (3c-1) (3c-2) is opened to the left and right sides, wherein the lower end of the product cast in the cavity of the lower mold (3c) inside the cavity through the control port 46b Since the lower pressurizing protrusion 45b, which has been introduced into the state, is inserted at a predetermined depth, even if the left and right split molds 3c-1 and 3c-2 are opened to the left and right side, the product is connected to the lower pressurizing protrusion 45b. It will remain captured.

21 shows demoulding and taking out the product from the mold-opening lower mold 3c. At this time, when the lower hydraulic cylinder 4b is operated to lower the lower plunger 41b, the lower plunger tip 42b is shown. The lower pressurizing protrusion 45b of the upper end is removed from the lower end of the product, so that the state enters into the control opening 46b, so that the product can be taken out. Therefore, the product can be taken out by the automatic taking out mechanism.

As described above, the present invention enables the casting of a liquid metal material based on molten metals such as casting and structural alloys by using a general mechanical press, and multi-stage pressure by primary to third pressure by mechanical press and hydraulic press of the press. By casting in operation, it can provide the effect that the tissue can produce the product with high density and good mechanical properties, and also reduce the investment cost of the equipment by using the mechanical press which is very inexpensive compared to expensive die casting or squeeze casting equipment. In addition, it is possible to produce the product to be molded by replacing only the mold according to the shape and size of the product, and according to the structural characteristics of the product, it is possible to select the mold with the structure of vertical separation, left and right separation, closed type, etc. Effect, and the existing die casting The squeeze casting method has a disadvantage of weak pressing force (approximately 175 MPa) to pressurize the metal material because the pressurization speed of the piston must be increased to prevent the liquid metal material from solidifying in order to inject and fill the liquid metal material into the mold cavity. However, in the present invention, after injecting the liquid metal material into the mold, the mold is formed at a high speed by a mechanical press, and at the same time, the first press is carried out and then pressurized to the ultra-high pressure by hydraulic pressure. Slower than the prior art, but can be cast at a larger pressing force (up to 350MPa) provides the effect of producing a product having a dense structure and excellent mechanical properties, the present invention is also conventional die casting or squeeze as shown in FIG. It can only be cast at lower temperatures than ordinary casting by casting Because time is short, LA has the advantage that enables improved productivity and can produce excellent mechanical properties of the product.

Claims (9)

Installing a mold (coupling) and opening (separating) operation between upper and lower molds by using a general mechanical press, and then injecting a liquid metal material into the cavity of the upper and lower molds by gravity; Lowering the upper mold to mold the lower mold and simultaneously pressing the metal material injected into the cavity of the lower mold with the force of a mechanical press; Subsequently, the final pressurization of the metal material filled in the cavity of the lower mold by using a hydraulic cylinder; and the metal material that is solidified proceeds from the moment it is injected into the cavity of the mold into a dense structure inside the cavity. Multi-stage pressurized die casting method using a press, characterized in that the casting by applying plastic deformation as possible. The method of claim 1, The liquid metal material is a multi-stage pressure die casting method using a press, characterized in that the upper and lower molds are injected (combined) into the cavity using gravity from the upper side of the upper mold. The method of claim 1, The liquid metal material is a multi-stage pressurized die casting method using a press, characterized in that the upper and lower molds are opened (separated) in the cavity using gravity from the upper side of the lower mold. The method of claim 1, The metal material being solidified by being injected into the cavity of the upper and lower molds is cast simultaneously by pressing the upper and lower hydraulic cylinders mounted on the upper and lower platens of the press at the same time. Multi-stage pressure die casting method using a press. The method of claim 1, The metal material injected into the cavity in the state in which the upper and lower molds are combined is first pressed from the upper side by the hydraulic pressure of the upper hydraulic cylinder formed on the upper platen of the press and then the lower hydraulic cylinder formed on the lower platen of the press. Multi-stage pressurized die casting method using a press, characterized in that the final pressurized from the bottom by the hydraulic pressure. The method according to any one of claims 1 to 5, In the upper and lower molds, the upper mold is joined to the lower mold by allowing the wedge moving toward the mold to catch the upper mold formed in the lower mold by the appearance of the piston rod of the cylinder for closing the mold during the lower platen lowering operation of the press. Multi-stage pressure type die casting method using a press, characterized in that to generate a clamping force that maintains a closed state. The method of claim 1, The liquid metal material is injected into gravity only in the cavity formed in the lower mold, and the upper mold is mechanically pressurized by the upper mold into the cavity by the lowering operation of the upper platen of the press, and then finally the hydraulic pressure of the hydraulic cylinder. Multi-stage pressure die casting method using a press, characterized in that the press is cast inside the lower mold. The method of claim 1, The lower mold is divided into left and right split molds which are combined and separated by left and right, and the upper mold is formed to maintain the clamping force of the lower mold by wrapping the inclined portion formed on the outer circumference of the lower mold in which the left and right split molds are combined. Multi-stage pressurized die casting method using a press, characterized in that the hollow wedge portion for giving. In a die casting mold having at least one cavity for casting a product, The cavity is the center portion so that the pressing force can be applied horizontally from the front side to the rear side of the cavity through a plurality of runners when pressing the metal material injected into the center of the upper and lower molds in the vertical direction. A multistage pressurized die-casting die using a press, which is formed in a circumferential direction in a circumferential direction.

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