Die cast manufacturing method and apparatus

Abstract

Provided are a die cast manufacturing method and apparatus, with which it is possible to shorten a manufacturing cycle by allowing a die cast product to be extracted upon completion of cooling the product without having to wait until a biscuit part cools down. In the die cast manufacturing method and apparatus, after molten metal is injected into clamped molds by a first pressure application means, second pressure application is conducted by a second pressure application means via a runner that is directly connected to a cavity. In a state where filling of the cavity by the molten metal is completed by the first pressure application means, a passageway between a die cast product part and the biscuit part is disconnected so as to allow the second pressure application means to apply pressure to the die cast product part, thereby enabling the die cast product part and the biscuit part to be cut apart and to be extracted upon opening the molds.

Description

Die-casting manufacturing method and device

[0001] The present invention relates to a die-casting manufacturing method and apparatus, and more particularly to a die-casting manufacturing method and apparatus capable of shortening a product manufacturing cycle.

[0002] A die-cast product is cast by forcing molten aluminum or other metal into a cavity created by a mold with a plunger and then removing a product shaped to match the cavity. To prevent porosity during cooling and molding, a method has been proposed for applying additional pressure to the runner in conjunction with the pressurizing operation of the die-casting machine's plunger. This method involves providing a pressure pin that moves in and out of a rising runner directly connected to the cavity. After the plunger pressurizes the product using the primary pressurizing means, the runner's pressure pin is activated to apply additional pressure (see Patent Document 1). In this case, the product is removed by grasping the biscuit portion connected to the product portion, and an automatic robot removes the entire as-cast product, consisting of the biscuit portion, runner portion, product portion, and air vent portion. The pressurization from the runner in Patent Document 1 has the drawback that the pressurized portion and the biscuit surface at the tip of the plunger are connected, causing the molten metal to flow back toward the plunger, preventing the riser effect from being achieved.

[0003] From this perspective, the technology described in Patent Document 2 has been proposed, which maintains the strength of the runner portion connecting the product portion and the biscuit portion while setting the gap between the inner diameter of the member forming the rising runner portion and the outer diameter of the pressure pin to 0.5 to 3.0 mm to exhibit backflow prevention function and obtain a pushing effect (Patent Document 2). However, although the gap Δ between the inner diameter of the member forming the rising runner portion and the outer diameter of the pressure pin is set to 0.5 to 3.0 mm, in practice, it is difficult to form such a cylindrical gap, resulting in a large gap and a certain gap length L. As a result, even if the pressure pin is inserted under pressure, the molten metal flows back through the gap Δ, pushing the plunger back, and the expected backflow prevention effect is not obtained.

[0004] Furthermore, after casting, the die-cast product is removed by grasping the biscuit portion with a robot chuck. The product and biscuit portions of the solidified casting are connected by a thin-walled cylindrical shape formed by the gap between the cylinder inner diameter and the pressure pin outer diameter, after the pressure pin is pressed into the cylinder where the runner portion is machined and installed. Therefore, if the gap between the rising runner cylinder portion and the moving runner pressure pin becomes thin, the strength of the portion connecting the biscuit and product portions decreases, resulting in breakage during product removal, leading to failure and disruption to continuous production. Conversely, if this gap is made larger, the second pressure effect of the runner pressure pin will cause molten metal to flow back through the gap, impairing the pressure effect. Furthermore, the manufacturing cycle time for die-cast products consists of the steps of mold clamping, filling with molten metal, injecting into the mold, cooling, mold opening, removing the as-cast product, injecting release agent, and mold clamping. However, the cooling time accounts for a large proportion of the cycle time, which is determined by the cooling time of the thick biscuit part, which takes the longest time to cool, and there was a limit to how much the product manufacturing cycle time could be shortened.

[0005] JP 2000-117411 JP 2011-224650

[0006] The present invention addresses the above-mentioned problems and aims to provide a die-cast manufacturing method and apparatus that can shorten the manufacturing cycle by enabling the die-cast product to be removed when cooling is complete without waiting for the biscuit portion to cool.

[0007] To solve the above problems, the present invention is configured as follows: A die-casting manufacturing method in which molten metal is injected into a clamped mold by a first pressurizing means, and then a second pressurizing is performed by a second pressurizing means through a runner directly connected to the cavity, characterized in that, after the first pressurizing means has completed filling the cavity with molten metal, the passages for the die-cast product portion and the biscuit portion are separated and the second pressurizing means pressurizes the die-cast product portion.

[0008] In this case, after the first pressurizing means has filled the mold with molten metal, the second pressurizing means separates the passages between the die-cast product portion and the biscuit portion with the pressure of the pressurizing pin, and pressurizes the die-cast product portion with the pressing force of the pressurizing pin. After the second pressurizing means has pressed the product portion, the die-cast product portion solidifies, leaving the biscuit portion in a semi-solid state, which is then opened by the mold removal device, and the product or a removal protrusion connected to the product is grasped by the product removal device, and the semi-solid biscuit portion is separated by the mold extrusion or forward injection motion of the machine. Furthermore, the quality of the product can be confirmed during casting by monitoring the stroke of the pressurizing pin.

[0009] The pressure applied to the molten metal including the die-cast product portion by the pressure pin of the second pressure means is greater than the pressure applied to the molten metal by the first pressure means.

[0010] In the center gate manufacturing method, after molten metal is injected into the clamped mold by the first pressure means, when the spool portion of the fixed mold is pressurized by the second pressure means, the pressure pin of the second pressure means pressurizes so as to separate the die-cast product portion and the biscuit portion at the runner portion connecting them.

[0011] The die-cast manufacturing apparatus of the present invention comprises a first pressure applying means for injecting molten metal into a clamped mold, a second pressure applying means having a pressure applying pin that is operated after the operation of the first pressure applying means is completed and applies pressure to a runner directly connected to the cavity, and a separating means provided in a position to separate and shield the die-cast product portion and the biscuit portion, wherein the separating means is provided with a control unit that, after the operation of the first pressure applying means is completed, enables the die-cast product portion and the biscuit portion to be separated and the die-cast product portion and the biscuit portion to be separated, and then enables the die-cast product portion to be pressurized by the second pressure applying means.

[0012] The die-casting mold further comprises a first pressurizing means for injecting molten metal into the clamped mold, a second pressurizing means having a pressurizing pin that is operated after the first pressurizing means has completed its operation and pressurizes a runner directly connected to the cavity, and a pressurizing path for the pressurizing pin that is provided at a position that separates the die-casting product portion and the biscuit portion, and the pressurizing path is characterized by having a control unit that enables the die-casting product portion and the biscuit portion to be separated by the operation of the pressurizing pin, and then enables the die-casting product portion to be pressurized by the second pressurizing means.

[0013] In such an apparatus, after the product portion is pressurized by the second pressurizing means, the control section opens the mold while the die-cast product portion is solidified and the biscuit portion is in a semi-solid state, and the product or the runner connected to the product is grasped by a product removal device, and the semi-solid biscuit portion is cut off by the mold extrusion or injection forward motion of the machine.

[0014] Furthermore, an injection section is provided having a first pressure means for injecting molten metal into the die-casting mold, and a second pressure means for bending a runner connected to the cavity and being provided in the runner section directly connected to the cavity at this bent section to apply pressure in the direction of the cavity, and after injection by the first pressure means is completed, a control section is provided which is provided in the pressure path by the pressure pin of the second pressure means and separates and shields the die-cast product section and the biscuit section between the pressure pin and the second pressure means, and then enables the product section to be pressurized by the pressure pin.

[0015] In this case, after the product part is pressurized by the second pressure means, the control unit causes the die-cast product part to solidify and the biscuit part to open the mold in a semi-solid state, and the product or the runner connected to the product is grasped by the product removal device, and the semi-solid biscuit part is cut off by the mold extrusion or injection forward motion of the machine.

[0016] With conventional die-casting manufacturing equipment, the "as-cast product" consisting of the biscuit, runner, product, and air vent sections after molten metal is injected into the mold is removed only after the entire "as-cast product" has solidified. The solidification speed varies depending on the biscuit, runner, product, and air vent sections. The solidification speed is proportional to the square of the wall thickness. For example, if the product thickness is 3 mm, the cooling time for the product section is approximately 0.09 seconds for 3 mm, while if the biscuit section is 30 mm, the cooling time for the product section is 9 seconds for 30 mm. In most cases, the thicker biscuit section is the slowest, and the solidification speed of the biscuit section determines the cycle time, or productivity, of die-casting product manufacturing.

[0017] In the present invention, the product portion and the biscuit are separated by a runner pressure pin that is pressed into the runner portion. This allows the mold to be opened and the product portion removed as soon as only the product portion has solidified, without waiting for the biscuit portion, which takes a long time to solidify. This shortens the cycle time and improves the productivity of die-cast product manufacturing. For example, if the product portion is 3 mm thick and the biscuit portion is 30 mm thick, the time to remove the "as-cast product" is reduced from 9 seconds to 0.09 seconds, significantly shortening the cycle time and improving productivity. Furthermore, the product portion can be removed in a less solidified state than before, which also results in reduced product deformation and galling during removal.

[0018] In order to separate the product portion and the biscuit portion at the runner portion using the runner pressure pin that presses the runner portion, the runner portion must be cut by the weight of the biscuit portion when the mold is opened, causing the biscuit portion to fall. For this reason, the gap formed by the diameter of the runner portion and the diameter of the runner pressure pin is set to a thickness that is sufficient to allow the biscuit portion to fall under its own weight. A gap of this size also prevents backflow of molten metal when the runner is pressurized. Because there is no backflow, the molten metal is forced at high pressure into the product portion that has already been filled by the first pressurizing means through the second pressurization by the runner pressure pin. By timing the start of the runner pressure pin's pressing action into the runner portion when the vicinity of the product portion that contacts the mold has solidified but the center of the product has not yet solidified, the molten metal in the product portion before solidification can be forced into it, effectively increasing its density.

[0019] Furthermore, by monitoring the stroke of the pressure pin (or the stroke of the cylinder), the amount of molten metal being pushed in can be measured, making it possible to check the quality of the product during casting.

[0020] In conventional runner pressurization, which does not separate the product portion and biscuit portion, the chucking portion for removing the product portion after cooling becomes the biscuit portion, but the runner portion diameter and runner pressurizing pin diameter must be set so that the biscuit portion and product portion do not separate when removed, and gap adjustment is required to minimize backflow and prevent separation. However, with the runner pressurization and separation method of this invention, there is no backflow at all, so the stroke amount and the increase in product weight are equal, making management easier.

[0021] Fig. 1 is a cross-sectional view of a main part of a die-casting manufacturing apparatus according to an embodiment; Fig. 2 is a cross-sectional view of a pressure pin attachment used in the die-casting manufacturing apparatus, and a cross-sectional view of a modified example; Fig. 3 is an explanatory view of opening the apparatus and separately removing the die-cast product and the biscuit part; Fig. 4 is a configuration diagram of a pin stroke detection device; Fig. 5 is a cross-sectional view of runner pressure using a center gate manufacturing method;

[0022] A die-cast manufacturing method and manufacturing apparatus according to an embodiment of the present invention will be described in detail below with reference to the drawings. Note that the following description is merely one embodiment, and various modifications may be made to the present invention as long as they do not deviate from the spirit of the present invention.

[0023] 1 shows a cross-sectional view of the essential parts of a die-casting production apparatus according to a first embodiment. The die-casting production apparatus 10 comprises a movable die 14 attached to a movable platen 12 and a fixed die 18 attached to a fixed platen 16. Molten metal is injected into a cavity 20 formed by bringing the dies 14, 18 into contact, resulting in a product having a shape that conforms to the cavity 20. The die-cast product can be removed from the cavity 20 by separating the dies 14, 18 and operating an ejector pin 22 provided on the back surface of the movable die 14.

[0024] A molten metal supply means 24 is disposed below the cavity 20 as an injection section for supplying molten metal to the cavity 20 of the die-casting manufacturing apparatus 10. This is composed of a first pressure means 30 consisting of an injection sleeve 26 that is attached by penetrating horizontally through the fixed platen 16 and reaches the fixed mold 18, a plunger 28 disposed within the injection sleeve 26, and a pressure device that is located behind the plunger 28 and can push and pull the plunger 28.

[0025] A runner 32 is formed at the front end of the injection sleeve 26, serving as a passage for the molten metal that passes through the biscuit 31 and reaches the cavity 20. This runner 32 consists of a diverter runner portion 34 that extends almost horizontally from the injection sleeve 26 and a rising runner portion 36 that turns upward so as to connect directly to the bottom of the cavity 20. The molten metal extruded by the plunger 28 of the first pressurizing means 22 passes through the diverter runner portion 34, is turned upward by the rising runner portion 36, and is injected and sprayed into the cavity 20.

[0026] The rising runner portion 36 of the runner 32 is provided with a second pressurizing means 38 that secondarily pressurizes the molten metal in the cavity 20. This second pressurizing means 38 is composed of an actuator (hydraulic cylinder) 40 mounted on the bottom of the molds 14, 18 and a pressurizing pin 42 attached so as to move in and out from the bottom to the top of the rising runner portion 36 using the actuator. The diameter d of the pressurizing pin 42 is smaller than the inner diameter D of the rising runner portion 36, but they are approximately the same diameter, allowing the pressurizing pin 42 to slide up and down in the rising runner portion 34 while dividing and shielding the molten metal. Therefore, the amount by which the pressurizing pin 42 is pressed into the rising runner portion 36 improves the density of the product formed by the cavity 20.

[0027] In this embodiment, in particular, in the straight path from the intersection of the rising runner section 36 and the diverter runner section 34 (section A-B in FIG. 2(1)) to the gate of the upper rising runner section 36, the inner diameter D of the section (section A-C in FIG. 2(1)) to the stroke end (C in FIG. 2(1)) of the pressure pin 42 is set to D = d + 0.1 mm to d + 0.5 mm, where D is the outer diameter of the pressure pin 42. Preferably, D is set to D = d + 0.2 mm to d + 0.4 mm. This is to ensure a range of motion for the pressure pin 42 and to prevent molten metal from entering any gaps.

[0028] The second pressurizing means 38 thus configured begins to apply pressure from the position shown in Figure 2(1)A after injection by the plunger 28 of the first pressurizing means 30 is completed. When the pressurizing pin 42 just interrupts the diverter runner portion 34 as shown in Figure 2(1)B, it separates the product portion 35 from the biscuit portion 31 at that point. Therefore, when the pressurizing pin 42 is pushed in to reach Figure 2(1)C, the amount of molten metal filled into the cavity 20 increases, the stroke of the pressurizing pin 42 becomes longer, and the manufacturing process is completed. At this point, the die-cast product portion 35 and the biscuit portion 31 in the cavity 20 are completely separated. Therefore, as shown in Figure 3, the molds 14, 18 are opened when the solidification time of the die-cast product portion 35 has elapsed. Even if the biscuit portion 31 is still hot and not yet completely cooled, the die-cast product 35 can be removed by the chuck robot 41, and the separated biscuit portion 31 can fall under its own weight. These drive controls may be performed by a separately provided control unit.

[0029] In this way, by using the runner pressure pin 42 to push into the runner, the product portion and the biscuit portion 31 are separated. This allows the molds 14, 18 to be opened and the product portion removed as soon as the product portion has solidified, without waiting for the biscuit portion 31, which takes a long time to solidify. This shortens the cycle time and improves the productivity of die-cast product manufacturing. If the product portion is 3 mm thick and the biscuit portion 31 is 30 mm, the time required to remove the "as-cast product" is reduced from 9 seconds to 0.09 seconds, shortening the cycle time and improving productivity. Furthermore, the product portion can be removed in a less solidified state than before, resulting in reduced product deformation and galling during removal.

[0030] In order for the runner pressure pin 42 that presses the runner portion 31 to separate the product portion from the biscuit portion 31 at the runner portion 31, the runner portion must be cut by the weight of the biscuit portion 31 and fall when the molds 14, 18 are opened. For this reason, the gap formed by the diameter of the runner portion 31 and the diameter of the runner pressure pin 42 must be thick enough to allow the biscuit portion 31 to fall under its own weight. This gap also prevents backflow of molten metal when the runner is pressurized. Because there is no backflow, the molten metal is forced at high pressure into the product portion already filled by the first pressurizing means 24 through the second pressurization by the runner pressure pin 42. By timing the start of the pressing operation of the runner pressure pin 42 into the runner portion when the vicinity of the product portion in contact with the mold has solidified but the center of the product is not solidified, the molten metal in the product portion before solidification can be forced into it, effectively increasing its density.

[0031] As a result, the die-cast product time can be used as the cycle time, and is not affected by the cooling time of the biscuit. In addition, since there is no need to hold the biscuit 31 when removing the die-cast product, product deformation and galling during removal do not occur.

[0032] In addition, the runner pressure pin can be used to separate the die-cast product from the biscuit portion, and pressure can be applied to the center of the product while it is still wet.This allows the molten metal to be forced into the die-cast product portion with a higher casting pressure (approximately 70 MPa → approximately 280 MPa) while maintaining the conventional clamping force (projected area * casting pressure), significantly increasing the internal density.

[0033] FIG. 2(2) shows a modified example of the pressure pin 42. This has an annular protrusion 43 with a diameter D at the inlet of the rising runner portion 36. The inner diameter D of the annular protrusion 43 and the diameter d of the pressure pin 42 are set to D = d + 0.1 mm to d + 0.5 mm. Preferably, D is set to D = d + 0.2 mm to d + 0.4 mm. The diameter E of the rising runner 36 is larger than D, so the dimensions can be approximate. With this configuration, there is almost no gap between the annular protrusion 43 and the pressure pin 42, and molten metal does not leak through this gap. Compared to the example in FIG. 2(1), this has the advantage of being easier to process because it is a ring-shaped body.

[0034] Furthermore, monitoring the pressure pin stroke (or cylinder stroke) allows for product quality confirmation during casting. The runner pressure separation method eliminates backflow, increasing the stroke and product weight, making it easier to manage. This can be achieved with the following configuration. Figure 4 shows the pin stroke detection device. As shown in the figure, the hydraulic pressure discharge path 44 is designed to measure the amount of oil discharged when the pressure pin 42 rises, thereby measuring the piston drive amount of the main actuator 40 and, ultimately, the stroke of the pressure pin 42. This stroke detection device 46 has a cylinder-piston structure, consisting of a cylinder body 48 and a piston 50 that slides within it. One chamber of the cylinder body 48, separated by the piston 50, is connected to the hydraulic oil outlet of the pressure pin 42, and the other chamber is connected to the directional control valve 52. As a result, hydraulic oil discharged from the main actuator 40 flows into the stroke detection device 76, moving the piston 50. A rod 54 is integrally formed with the piston 50, protruding from one end of the cylinder body 48 and connected to a linear potentiometer 56. The rod 54 starts to move at one end of the cylinder body 48 (the left end in FIG. 3 ), which coincides with the pressure start point of the pressure pin 42 (the lower end in FIG. 3 ). The linear potentiometer 56 is disposed parallel to the rod 54 and moves with it to measure its travel distance. In this stroke detection device 46, the piston 50 is provided with a through-hole that connects the chambers separated by the piston 50, and a check valve 58 and an orifice (throttle valve) 60 are attached to this through-hole. The check valve 58 is a one-way valve that prevents hydraulic oil from flowing from the chamber containing hydraulic oil for the pressure pin 42 to the chamber on the directional control valve 52 side, but allows flow in the opposite direction. This allows the stroke detection device 46 to detect the total amount of hydraulic oil when the pressure pin 42 performs a pressure application. An orifice (throttle valve) 59 regulates the flow rate of the check valve 58. If the cracking pressure (spring force) of the check valve 58 is weak, the fluid will flow through the check valve when the piston is stopped, so this can be solved by restricting the flow rate.A control means for controlling the above-described operating system is provided separately to ensure proper operation.

[0035] By providing such a stroke detection device 46 for the pressure pin 42, the pressure pin can be accurately monitored, and this operation alone can measure the amount of secondary pressure applied to the die-cast product.

[0036] Next, Fig. 5 shows an example of application to the "center gate manufacturing method." The "center gate manufacturing method" is applied to circular or conical shaped parts and point-symmetric parts, and is used to fill the molten metal from the center of the cavity 66 to improve filling balance.

[0037] As shown in FIG. 5 , the center gate molding method is performed in an apparatus having a second movable mold 64 disposed between a fixed mold 60 and a movable mold 62. A circular cavity 66 is formed between the movable mold (hereinafter referred to as the first movable mold) 62 and the second movable mold 64. A spool 70 is formed in the second movable mold 64, connecting the cavity 66 to a runner 68. The spool 70 is conically shaped, with its apex located at the center of the circular cavity 66. By supplying molten metal from the apex, the molten metal is distributed throughout the cavity 66 through the spool 70. The runner 68 is formed on the mating surface of the fixed mold 60, bends at a right angle from the apex of the spool 70, and extends downward. The runner 68 is connected to a horizontally extending plunger sleeve 72 disposed below the fixed mold 60. A plunger 74 is inserted into the plunger sleeve 72, and a primary pressure is applied by an actuator (not shown) to inject the molten metal. The pressurizing means including the plunger 74 is the first pressurizing means 76 .

[0038] A second pressure means 80 is provided on the fixed mold 60 side, facing the apex of the spool 70. This means comprises a pressure cylinder 82 and a pressure pin 84 that moves in and out of the pressure cylinder 82. The pressure pin 84 moves in and out toward the apex of the spool 70 formed in the second movable mold 64. Specifically, as shown in the enlarged portion of Figure 5, the pressure pin 84 moves in and out through a curved passage 86 provided at the location connecting the runner 68 and the spool 70. This passage is formed inside the second movable mold 64 and connects to the cavity 66. The pressure pin 84 traverses the runner 68 and pressurizes the cavity 66 as soon as it reaches the curved passage 86.

[0039] Here, the relationship between the inner diameter D of the curved passage 86 and the outer diameter d of the pressure pin 84 is D = d + 0.1 mm to d + 0.5 mm. Desirably, D is set to D = d + 0.2 mm to d + 0.4 mm. This is to ensure a range of motion for the pressure pin 84 and to prevent the molten metal from entering into any gaps. As shown in the enlarged view of Figure 5 (the lower view of the same figure), the amount of pressure applied by the pressure pin 84 determines the amount of pressure applied to the cavity 66.

[0040] To explain the actual operation steps of this "center gate manufacturing method," first, in the mold clamping state, the first pressurizing means 76, the gate-cutting hydraulic cylinder 78, and the second pressurizing means 80 are all in standby mode. First, molten metal is poured through the inlet of the plunger sleeve 72. After pouring is complete, the first pressurizing means 76 begins operation, moving at high speed and completing the low-speed, high-pressure injection at its forward limit. The molten aluminum enters the runner 68, rises, passes through the curved passage 86, and is filled into the cavity 66 from the spool 70. After the injection operation by the first pressurizing means 76 is completed, secondary pressurization is performed by the second pressurizing means 80. This is done by pushing the pressurizing pin 84 from its standby position (upper view of the enlarged view in Figure 5 ) using the pressurizing cylinder 82. The pressurizing pin 84 crosses the runner 68 and reaches the curved passage 86, where it performs its function of dividing and blocking the molten metal. Therefore, the separating function of the pressure pin 84 increases the amount of molten metal filled into the cavity 66, and the pushing action of the pressure pin 84 lengthens the stroke, completing the process. Next, the first movable mold 62, including the second movable mold 64, is moved back, and one side of the intermediate mold is opened. This brings the runner 68 into contact with the cavity 66. In this mold-open state, the die-cast product portion and the biscuit portion 31 are separated, making it easy to remove the biscuit. Finally, the first movable mold 62 is moved back further, widening the gap between the second movable mold 64 and the first movable mold 62 of the intermediate mold, and the product is removed from the cavity 66, completing the process.

[0041] Thus, according to the "center gate manufacturing method," the pressure pin 84 of the second pressure means 80, which applies pressure to the spool 70 located at the center of the cavity 66, blocks the curved passage 86 leading to the product portion, completely blocking the backflow of molten metal and maintaining pressure, thereby enabling additional pressure to be applied to the product portion. Furthermore, it is no longer necessary to place the second pressure means 80 below the runner 68, and the second pressure means 80 does not get in the way.

[0042] Thus, the center gate manufacturing method also fully achieves the effects of the present invention. That is, according to this embodiment, there is no need to first install a hydraulic cylinder for gate cutting. Even if a hydraulic cylinder is installed, it is sufficient to simply peel the runner portion from the second movable mold 64. Because the die-cast product portion and the biscuit portion 31 are separated, the cycle can be set based on the time it takes for the die-cast product portion to cool and solidify. Since the biscuit portion 31 does not need to be completely cooled during heating, the product manufacturing cycle time can be significantly reduced.

[0043] In the present invention, after molten metal is injected into a clamped mold by a first pressurizing means, a second pressurizing is performed by a second pressurizing means through a runner directly connected to the cavity.When the molten metal has completely filled the cavity by the first pressurizing means, the die-cast product portion and the biscuit portion can be separated and pressurized by the second pressurizing means, thereby shortening the product manufacturing cycle time.

[0044] 10...Die casting manufacturing apparatus, 12...Moveable platen, 14...Movable mold, 16...Fixed platen, 18...Fixed mold, 20...Cavity, 22...Ejector pin, 24...Water supply means, 26...Injection sleeve, 28...Plunger, 30...First pressurizing means, 32...Runner, 34...Diverter runner portion, 36...Rising runner portion, 38...Second pressurizing means, 40...Actuator, 42...Pressure pin, 44...Hydraulic pressure discharge path, 46...Pin stroke detection device, 48...Cylinder body, 50...Piston, 52...Directional switching valve, 54...Rod, 56...Potentiometer, 58...Check valve, 59...Throttle valve, 60...Fixed mold, 62...First movable mold, 64...Second movable mold, 66...Cavity, 68...Runner, 70...Spool, 72...Plunger sleeve, 74...Plunger, 76...First pressure means, 78...Gate cutting hydraulic cylinder, 80...Second pressure means, 82...Pressure cylinder, 84...Pressure pin, 86...Bent passage.

Claims

1. A die casting manufacturing method comprising: injecting molten metal into a clamped die by a first pressurizing means, and then applying a second pressurization by a second pressurizing means through a runner directly connected to a cavity, A die casting manufacturing method characterized in that when the first pressurizing means has completely filled or nearly filled the cavity with molten metal, the second pressurizing means is operated to separate the passages between the die-cast product portion and the biscuit portion, and the die-cast product portion is pressurized by the second pressurizing means while blocking the molten metal via an annular protrusion provided at the runner inlet portion immediately after separation.

2. (delete)

3. The die casting method according to claim 1, characterized in that after the product portion is pressurized by the second pressurizing means, the die-cast product portion is solidified and the biscuit portion is opened in a semi-solid state, the removal protrusion of the product or the runner portion connected to the product is grasped by a product removal device, and the semi-solid or solidified biscuit portion is cut off by the die extrusion or injection forward motion of the machine.

4. 2. The die casting manufacturing method according to claim 1, wherein the stroke of the pressure pin is monitored to confirm the quality of the product during casting and to determine whether the stroke has reached the dividing position.

5. 2. The die casting manufacturing method according to claim 1, characterized in that the pressure acting on the molten metal including the die-cast product portion by the pressure pin of the second pressure means is greater than the pressure acting on the molten metal by the first pressure means.

6. This is a die-casting manufacturing method in which, in the center gate manufacturing method, after molten metal is injected into a clamped mold by a first pressurizing means, the spool portion of the fixed mold is pressurized by a second pressurizing means, the runner portion connecting the die-cast product portion and the biscuit portion is separated by a pressurizing pin of the second pressurizing means, and the molten metal is blocked via an annular protrusion provided at the runner inlet portion immediately after separation, while the product is pressurized by the pressurizing pin.

7. A first pressurizing means for injecting molten metal into the clamped mold; a second pressurizing means having a pressurizing pin which is operated after the operation of the first pressurizing means is completed and pressurizes a runner directly connected to the cavity; A dividing means is provided at a position for dividing and shielding the die-cast product portion and the biscuit portion; an annular protrusion that is provided at the inlet of the runner immediately after separation and serves to shield the molten metal; The die-casting manufacturing apparatus is characterized in that the separating means is provided with a control unit which enables the die-casting product portion and the biscuit portion to be separated from each other after the operation of the first pressurizing means has been completed or is nearly filled, and then enables the die-casting product portion to be pressurized by the second pressurizing means which has passed through the annular protrusion.

8. A first pressurizing means for injecting molten metal into the clamped mold; A second pressurizing means having a pressurizing pin which is operated after the operation of the first pressurizing means is completed or after the filling is almost completed, and pressurizes a runner directly connected to the cavity; a pressure path for the pressure pin provided at a position separating the die-cast product portion and the biscuit portion; an annular protrusion that is provided at the inlet of the runner immediately after separation and serves to shield the molten metal; The die-cast manufacturing apparatus is characterized in that the pressure path is provided with a control unit that enables the die-cast product portion and the biscuit portion to be separated and separated by the operation of a pressure pin, and then enables the die-cast product portion to be pressurized by a second pressure means that has passed through the annular protrusion.

9. The control unit is characterized in that after the product part is pressurized by the second pressurizing means, the die-cast product part is solidified and the biscuit part is opened in a semi-solid or solidified state, the product or the runner connected to the product is grasped by a product removal device, and the semi-solid biscuit part is separated by the die extrusion or injection forward motion of the machine. The die casting manufacturing apparatus according to claim 7 or 8.

10. A first pressurizing means for injecting molten metal into a die casting mold; a second pressurizing means provided in a runner portion directly connected to the cavity at the bent portion and applying pressure in a direction toward the cavity; a ring-shaped protrusion through which the pressure pin can be inserted is provided at a runner inlet portion that serves as the pressure path; A die-casting manufacturing apparatus characterized by having a control unit provided in a pressure path applied by a pressure pin of a second pressure means, which separates and shields the die-cast product portion and the biscuit portion between the pressure pin and the second pressure means after completion of injection by the first pressure means, and then enables the product portion to be pressurized by the pressure pin.