JP7727309B2 - Partial ultra-high pressure die casting manufacturing method and device - Google Patents

Description

The present invention relates to a die-casting manufacturing method and device using partial ultra-high pressure, and in particular to a die-casting manufacturing method and device that improves the density of the product by providing a pouring pool in a branched runner that serves as the molten metal inlet for the mold, attaching an ultra-high pressure pressurizing cylinder, and pressing with a pressure pin connected to it.

Die-cast products are cast by forcing molten metal such as aluminum into a cavity made in a mold with a plunger, and then removing the product that has solidified to a shape that matches the cavity. To prevent voids from forming when the product is formed, a method has been proposed in which the runner is further pressurized in conjunction with the pressure action of the plunger.

The runner consists of a branch runner that runs in the direction of the plunger's extrusion and a rising runner that runs perpendicular to it. In order to locally apply pressure to the runner, a pressure pin that moves in and out of the rising runner that is directly connected to the cavity is provided, and after the plunger has completed applying pressure, the pressure pin of the runner is activated to apply further pressure (Patent Document 1).

In a method like that described in Patent Document 1, the molten metal forced into the cavity is already solidifying, so when the runner is pressurized, the molten metal flows back and is pushed back toward the plunger, resulting in the desired cavity-pushing effect being unsuccessful. In response to this issue, Patent Document 2 proposes a technology in which the gap between the inner diameter of the member forming the rising runner and the outer diameter of the pressure pin is uniformly set to 0.5 to 3.0 mm to prevent backflow and achieve a pushing effect. Generally, the flow rate Q of the annular gap is proportional to the cube of the annular gap Δ and inversely proportional to its length L. Therefore, minimizing the gap Δ is important. However, while the gap Δ between the inner diameter of the member forming the rising runner and the outer diameter of the pressure pin is set to 0.5 to 3.0 mm, it is difficult to actually form such a cylindrical gap, resulting in a large gap and a necessary gap length L. As a result, even when the pressure pin is inserted under pressure, the molten metal flows back through the gap Δ, pushing back the plunger, resulting in the expected backflow prevention effect being unsuccessful.

In particular, with conventional methods, plunger injection may be performed from multiple branch runners depending on the product shape created by the cavity, and in such cases, there is a problem of reduced density in the part of the product injected from a specific branch runner. This is even more difficult when the branch runner is not connected to the location where the voids occur, or when manufacturing is performed via a single runner.

JP 2000-117411 JP 2011-224650

The present invention addresses the above-mentioned problems and aims to provide a die-casting manufacturing method and apparatus that, when pressurizing the runners after injecting molten metal with a plunger through multiple branch runners, applies high pressure to selected branch runner sections at a specific level to continuously solidify the molten metal, thereby producing dense die-cast products through partial ultra-high pressure, improving the density of the intended area. Furthermore, by forming additional new branch runners and applying secondary pressure from these runners, dense die-cast products can be produced.

In order to achieve the above-mentioned objectives, the present invention is configured as follows. Specifically, the partial ultra-high pressure die casting method of the present invention is characterized by: injecting molten metal into a clamped mold via multiple branch runners using a primary pressure means; selecting a branch runner that communicates with the part where density improvement is desired; providing a pressure path midway through this branch runner that allows for a molten metal pool; providing an orifice in the pressure path toward the product; and providing a pressure pin for secondary pressure means that moves within the branch runner in the same direction as the flow of molten metal; and applying pressure using the pressure pin for secondary pressure means after injection by the primary pressure means is complete.

Alternatively, a primary pressure means can inject molten metal into the clamped mold via multiple branch runners and a newly set branch runner that connects to the area where density improvement is desired, and a pressure path can be set up in the middle of this new branch runner at a location where a molten metal pool can be secured. An orifice can be set up in the pressure path leading toward the product, and a pressure pin for a secondary pressure means can be set up that moves within the branch runner in the same direction as the flow of the molten metal, and after injection by the primary pressure means is complete, the runner can be pressurized by the pressure pin for the secondary pressure means.

Furthermore, a new branch runner connected to the part where density improvement is desired can be added to a mold with a single runner structure, and molten metal can be injected into the clamped mold via the runner using a primary pressure means. A pressure path can be provided in the middle of the added branch runner at a part where a molten metal pool can be secured. An orifice can be provided in the pressure path, and a pressure pin for a secondary pressure means can be provided that moves within the branch runner in the same direction as the flow of the molten metal. After injection by the primary pressure means is complete, pressure can be applied using the pressure pin for the secondary pressure means.

It is also possible to create a die casting manufacturing method that uses local ultra-high pressure to improve the density of the intended area by injecting molten metal into a clamped mold via multiple branch runners using a primary pressure means, selecting a branch flow base runner that connects to the area where density improvement is desired, providing a pressure path in the middle of this branch runner where a molten metal pool can be secured, providing an orifice in the pressure path toward the product and providing a pressure pin for a secondary pressure means that moves within the branch runner in the same direction as the flow of molten metal, and applying pressure using the pressure pin for the secondary pressure means after injection by the primary pressure means is complete.

In these cases, the secondary pressurizing means prevents pressure from the secondary pressurizing means from being transmitted to the primary pressurizing means device by blocking the basin with the pressurizing pin and creating a metal seal with a small gap between the orifice and the pressurizing pin, making it possible to apply high pressure from the secondary pressurizing means to the product portion.

Furthermore, the start time of the secondary pressurizing means after the completion of injection by the primary pressurizing means may be set by providing a control mechanism.
Furthermore, the pressure pin of the secondary pressure means attached to the branch runner and the pressure cylinder for driving it may be set on either the fixed mold side or the movable mold side of the mold.

The ultra-high pressure die casting device of the present invention is characterized by comprising: a primary pressure applying means for injecting molten metal into a die casting mold through multiple branch runners; a secondary pressure applying means for selecting a portion of the branch runners and attaching it to the selected branch runner to apply a higher pressure than that applied by the primary pressure applying means; a control unit for setting the start time for operating the secondary pressure applying means after the primary pressure applying means has completed filling of the molten metal product; and an orifice formed in the pressure path surface of the secondary pressure applying means.

Alternatively, the die-casting mold may be configured with a primary pressure applying means that injects molten metal through multiple branch runners and a newly installed branch runner that connects to the portion where density improvement is desired; a secondary pressure applying means that is attached to this new branch runner and that can apply a higher pressure than the primary pressure applying means; a control mechanism that sets the start time for operating the secondary pressure applying means after the primary pressure applying means has completed filling of the molten metal product; and an orifice formed in the pressure applying path surface of the secondary pressure applying means.

Furthermore, the die-casting mold may comprise a primary pressure means that injects molten metal through a single runner and a newly installed branch runner that connects to the portion where density improvement is desired; a secondary pressure means that is attached to this new branch runner and that can apply a higher pressure than the primary pressure means; a control mechanism that sets the start time for operating the secondary pressure means after the primary pressure means has completed filling the molten metal product; and an orifice formed on the pressure path surface of the secondary pressure means.

Also, a partial ultra-high pressure die casting device can be provided that comprises a primary pressure applying means for injecting molten metal into a die casting mold through multiple branch runners; a secondary pressure applying means that selects a branch runner base runner before the branch runner that is connected to the portion where density improvement is desired and is attached to the selected branch runner base runner to enable pressurization at a higher pressure than the primary pressure applying means; a control unit that sets the start time for operating the secondary pressure applying means after the primary pressure applying means has completed filling of the molten metal product; and an orifice formed in the pressure path surface of the secondary pressure applying means.

In these cases, the secondary pressure means may be provided on the fixed mold side, or may be provided so as to be able to apply pressure along the mold clamping surface.

With the above configuration, the molten metal is injected via a branch runner operated by a plunger as primary pressurization means, followed by pressurization by a pressure pin as secondary pressurization means. Therefore, the gates at the cavity entrances of runners other than those equipped with secondary pressurization means solidify, blocking backflow. At the same time, the orifices installed in the pressurization passages of the secondary pressurization means form metal seals due to their throttling effect. Therefore, the secondary pressurization means allows for appropriate partial pressurization at ultra-high pressure. This allows for partial pressurization of the product at ultra-high pressure, eliminating porosity that may have occurred locally. Branch runners can be selected for the mold to address areas where high density is desired, or new branch runners can be installed in areas where no runners are installed for areas where high density is desired. Furthermore, new branch runners can be installed in molds with a single runner. In such cases, high-pressure injection can be reliably performed in a partial secondary pressurization, thereby enabling the production of die-cast products without porosity.

1 is a schematic front view of a die-cast product including a runner injected by an ultra-high pressure die-cast manufacturing apparatus according to an embodiment. FIG. FIG. 2 is a schematic side view of FIG. 1; FIG. 10 is a cross-sectional view of a secondary pressure means attached to a branch runner portion. FIG. 10 is a schematic front view of a die-cast product including a runner injected by an ultra-high pressure die-cast manufacturing apparatus according to another embodiment. FIG. 5 is a schematic side view of FIG. 4.

Below, a partial ultra-high pressure die casting manufacturing method and manufacturing apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings. Please 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.

Figures 1 and 2 show a schematic front view and a schematic side view of a die-cast product produced by the partial ultra-high pressure die-casting production equipment of this embodiment, the branch runners leading to the product, and the mounting position of the ultra-high pressure pressurizing cylinder attached to that particular branch runner. As shown in these figures, the die-cast product 10 begins with the biscuit 12 extruded from the plunger side at its front end. The runner that serves as the passage from the biscuit 12 to the cavity bends and rises upward (diverter base runner 14), which further branches into multiple runners (four in the illustrated example) (branch runners 16a, 16b, 16c, 16d), which open at four locations on the die-cast product 10 via gates 18a, 18b, 18c, 18d.

As shown in Figure 1, there was a problem with the tendency for cavities to form when the molten metal injected from the left-hand branch runner 16a solidified within the product. Therefore, this branch runner 16a was selected as the runner connected to the intended product portion. After the amount of molten metal required for the die-cast product 10 was injected using the primary pressure means 20 (see Figure 2), secondary pressure was applied at an ultra-high pressure approximately four times higher than the primary pressure using the secondary pressure means 22 (see Figure 3) attached to the selected branch runner 16a.

The primary pressure applying means 20 and secondary pressure applying means 22 will be explained with reference to Figures 2 and 3. The die-casting manufacturing apparatus comprises a movable mold 24 attached to a movable platen and a fixed mold 26 attached to a fixed platen. Molten metal is injected into a cavity 28 formed by clamping the two molds 24, 26 together, resulting in a die-cast product 10 shaped to match the cavity 28. The product 10 can be removed from the cavity 28 by separating the molds 24, 26 and activating an ejector pin attached to the back of the movable mold 24.

To supply molten metal to the cavity 28 of such a die-casting manufacturing device, a molten metal supply means is positioned below the cavity 28 as the injection section of the primary pressure means 20. As shown in Figure 2, the primary pressure means 20 is composed of an injection sleeve 30 that is attached by penetrating horizontally through the fixed platen and reaches the fixed mold 26, a plunger 32 disposed within the injection sleeve 30, and a pressure device (not shown) located behind the plunger 32 that can push and pull the plunger 32.

A runner is formed above the front end of the injection sleeve 30, serving as a passageway leading to the cavity 28. This consists of a diverter base runner 14 before branching and four branch runners 16a, 16b, 16c, and 16d. Molten metal is injected into the cavity 28 through the subsequent gates 18a, 18b, 18c, and 18d to form the die-cast product 10. Let's assume that this die-cast product 10 has a problem with many voids occurring in the part of the product injected from the branch runner 16a at the left end of Figure 1.

Therefore, this branch runner 16a is selected, and secondary pressure is applied at the selected branch runner 16a. In this embodiment, the secondary pressure applying means 22 is disposed on the clamping surface of the mold, as shown in Figure 3, and the operating direction of the pressure applying pin 34 that constitutes the secondary pressure applying means 22 is set to be an upward direction perpendicular to the extrusion direction of the plunger 28.

In Figure 3, this selective branch runner 16a has a curved shape consisting of a first branch runner 36 that branches off from the branch base runner 14, which extends almost vertically from the injection sleeve 30, turns diagonally upward, and a rising runner 38 that continues vertically. The rising runner 38 is ultimately connected by turning upward so as to directly connect to the bottom of the cavity 28. The molten metal extruded by the plunger 32 passes through the branch base runner 14, turns upward by the rising runner 38, and is injected and sprayed into the cavity 28 from the gate 18a. The stroke of the pressure pin 34 on the rising runner 38 of this selective branch runner 16a forms the molten metal pool required for secondary pressure application.

The first branch runner 36 of this branch runner 16a is provided with a secondary pressurizing means 22 that secondarily pressurizes the molten metal in the cavity 28. The secondary pressurizing means 22 is provided along the mold clamping surface and consists of a lower actuator 40 and a pressurizing pin 34 attached so that it moves in and out along the rising runner 38 (pressurizing path). The diameter d of the pressurizing pin 34 is smaller than the inner diameter D of the rising runner 38, allowing the pressurizing pin 34 to slide up and down on the rising runner 38. Therefore, the amount of pressure the pressurizing pin 34 presses into the rising runner 38 (the amount of molten metal it displaces) improves the density of the product created by the cavity 28.

In this embodiment, an orifice 44 that narrows the inner diameter of the selected branch runner 16a is formed on the first diverter runner 36 side (section B in Figure 3) of the intersection of the first diverter runner 36 and the rising runner 38 (section A-B in Figure 3). This orifice 44 is an annular protrusion 46 with a rectangular cross section formed on the inner diameter of the rising runner 38. The height of this annular protrusion 46 is adjusted as closely as possible to the outer diameter d of the pressure pin 34 to create a metal seal. Specifically, although this depends on the size of the cavity 28, empirically, a gap of approximately 1 mm between the pressure pin 34 and the rising runner 38's annular protrusion 46 is desirable, as this provides a metal seal due to the solidification of the molten metal. This optimal value varies depending on the axial length of the annular protrusion 46, mold shape, injection pressure, and injection speed, but is often approximately 0.5 mm to 1.0 mm on average. Additionally, the axial length L of the annular protrusion 46 is often around 10 mm on average to achieve a high metal seal effect, but this varies depending on the mold shape, injection pressure, speed, etc. These factors ensure a reliable metal seal.

When the pressure pin 34 of the secondary pressure means 22 configured in this manner reaches the annular protrusion 46 after injection by the plunger 32 of the primary pressure means 20 is completed, the molten metal from above penetrates the orifice 44, forming a metal seal that provides a shielding function. This metal seal at the orifice 44 increases the amount of molten metal filled into the cavity 28, and the pushing action of the pressure pin 34 lengthens the stroke, completing the operation.

The start time of the secondary pressurizing means 22 after completion of injection by the primary pressurizing means 20 (approximately 70 MPa) can be set using the control mechanism 48. In this example, the secondary pressurizing means 22 is started approximately 0.1 seconds after completion of injection by the primary pressurizing means. While the optimum value for this delay time varies on the order of milliseconds depending on various conditions, such as the mold shape, first pressurizing pressure, and pressurizing speed, and therefore requires some trial and error, the time setting for this device can be set on the order of milliseconds. This time setting utilizes the metal seal at the injection ports of the non-selected branch runners 16b, 16c, and 16d, which are not equipped with the secondary pressurizing means 22. The molten metal solidifies upon contact with the mold, while the remaining areas are in a semi-solidified state. Therefore, by achieving a metal seal at the non-selected branch runners 16b, 16c, and 16d, while also achieving a metal seal at the orifice 44, partial pressurization by the secondary pressurizing means 22 can be performed at an ultra-high pressure (approximately 250 MPa). In other words, partial pressurization approximately four times that of the primary pressurizing means 20 is possible.

The annular protrusion 46 that forms the orifice 44 may have a rectangular cross section as in the embodiment, but it can also have a V-shaped or arc-shaped cross section. In this case, if the tip of the V-shaped or arc-shaped protrusion is sharp, it will be difficult to remove the metal seal, so it is desirable to have a shaved tip.

In addition, a cooling means can be placed on the annular protrusion 46 that forms the orifice 44. This can be a horizontal, water-cooled, or oil-cooled method, and it is recommended that cooling be performed when injection by the primary pressure means 20 is completed and pressure is applied to the annular protrusion 46 by the secondary pressure means 22. This makes it easier to form a metal seal.

In the above embodiment, the annular protrusion 46 that forms the orifice 44 can be formed as a separate part and attached using a snap-in structure when forming the runner 16a. This is because the runner 16a is split vertically along the mold parting line, making it easy to attach to the semicircular rising runner 38.

The above example can also be applied to pushing runners in a hot chamber and when molding plastic.

In this embodiment, injection into the cavity 28 is performed by the primary pressurizing means 20, and the secondary pressurizing means 22 is activated a short time after the runner 16a is filled with molten metal. As a result, normal extrusion occurs while the pressure pin 34 reaches the intersection of the first branch runner portion 36 and the rising runner 38 (Figure 3A-B). However, as soon as the first branch runner 36 breaks and reaches the orifice 44, the annular protrusion 46 reaches the section, and the molten metal solidifies in the gap δ due to the metal seal, blocking the pressure. At this time, the injection ports of the non-branch selection b runners 16b-16d are in a solidified state, blocking the openings. Therefore, the unsolidified runner molten metal on the cavity 28 side, located above the pressure pin 42, is pushed toward the cavity 28 against the backdrop of the blocked pressure.

This allows the pressure pin 34 to advance further than with conventional strokes, and the secondary pressure means 22 can produce a product with higher strength and density in some areas. The effect of this is a 1.7% weight increase when filling a cavity 28 of the same volume with molten metal, an astonishing value in this industry.

While the above embodiment illustrates an example in which the secondary pressure means 22 is positioned along the direction perpendicular to the plunger stroke (mold clamping surface), the secondary pressure means 22 may also be positioned so that it can apply pressure along the fixed mold 26 side. This second embodiment is shown in Figures 4 and 5. In this example, the product portion 33 is flat, so the mold clamping line is perpendicular to the plate surface. The plunger 32, which is the primary pressure means 20, is configured to move from the front to the back in the figure, and is pushed out into the die-cast product 10 via paths from four branch runners 16a, 16b, 16c, and 16d. The secondary pressure means 22, which is activated after the primary pressure means 20 has completed ejection, forms a runner section in the selected branch runner 16a that is parallel to the operating direction of the plunger 32. The secondary pressure means 22 is attached to this parallel runner 50 and applies pressure parallel to the plunger 32. In this case, an orifice 44 is provided in the parallel runner 50, and the pressure pin 34 slides through it. The start of pressurization by this secondary pressurizing means 22 is also delayed slightly after the completion of injection by the primary pressurizing means 20, and is configured to operate after the delay time set in the control mechanism 48. This makes it possible for the secondary pressurizing means 22 to produce partial ultra-high pressure (250 MPa).

In the example shown in Figures 4 and 5, the secondary pressure means 22 is mounted with a pressure pin 34 along with an actuator 40 inside the fixed mold, but if this does not fit, the actuator 40 may be extended and positioned on the fixed platen side.

In addition, the above example assumes that the product has branch runners 16a-16d from the beginning, but if a relatively large number of new voids are found in the product apart from the branch runner sections, a new branch runner can be provided toward that location, and this new runner section can be subjected to a partial pressure (approximately 250 MPa) higher than the plunger pressure (approximately 70 MPa) by the secondary pressure means 22. Furthermore, in the case of a mold that forms a product with a single runner, forming a new runner section and providing the secondary pressure means 22 there can also partially prevent void formation, making it possible to respond to each product in detail.

Furthermore, if there are multiple branch runners leading to the area where the density needs to be increased, they can be grouped together into a branch base runner, and a secondary pressure means can be provided on this branch base runner, allowing the multiple branch runners to be subjected to secondary pressure.

This invention is a method and apparatus for die casting production that allows for plunger pressure to be applied as a primary pressure means, followed by the use of a secondary pressure means to apply pressure to selected or new runners in areas requiring strength, thereby improving product density.

10...Die-cast product, 12...Biscuit, 14...Diverter base runner, 16a, 16b, 16c, 16d...Branch runners, 18a, 18b, 18c, 18d...Gate, 20...Primary pressure means, 22...Secondary pressure means, 24...Moveable mold, 26...Fixed mold, 28...Cavity, 30...Injection sleeve, 32...Plunger, 34...Pressure pin, 36...First diverter runner, 38...Rising runner, 40...Actuator, 44...Orifice, 46...Annular protrusion, 48...Control mechanism, 50...Parallel runner.

Claims (13)

Molten metal is injected into the clamped mold via a plurality of branched runners by a primary pressure means,
A branch runner is selected that is connected to the part where density improvement is desired, and a pressurization path is provided in the middle of this branch runner so that a pouring pool can be secured.
An orifice is provided in the pressure path directed toward the product, and a pressure pin for a secondary pressure means is provided which moves in the branch runner in the same direction as the flow of the molten metal,
A minute gap is formed between the orifice and the pressure pin, thereby enabling a metal seal to be formed,
A die casting manufacturing method for improving the density of a desired part by applying a partial ultra-high pressure, characterized in that pressure is applied by a pressure pin for the secondary pressure means after completion of injection by the primary pressure means. Molten metal is injected into the clamped mold by a primary pressure means via multiple branch runners and a newly set branch runner that is connected to the part where density improvement is desired,
A pressurized path is provided in the middle of this new branch runner where a pouring pool can be secured.
An orifice is provided in the pressure path directed toward the product, and a pressure pin for a secondary pressure means is provided which moves in the branch runner in the same direction as the flow of the molten metal,
A minute gap is formed between the orifice and the pressure pin, thereby enabling a metal seal to be formed,
A die casting manufacturing method for improving the density of intended parts by applying local ultra-high pressure, characterized in that after completion of injection by the primary pressure means, runner pressure is applied by the pressure pin for the secondary pressure means. A branch runner is newly added to a mold with a single runner structure, which connects to the area where density improvement is desired, and molten metal is injected into the clamped mold via the runner using a primary pressure means.
A pressurizing path is provided in a portion of the added branch runner where a pouring basin can be secured,
an orifice is provided in the pressurizing path, and a pressurizing pin for a secondary pressurizing means is provided which moves in the branch runner in the same direction as the flow of the molten metal;
A minute gap is formed between the orifice and the pressure pin, thereby enabling a metal seal to be formed,
A die casting manufacturing method for improving the density of a desired part by applying a partial ultra-high pressure, characterized in that pressure is applied by a pressure pin for the secondary pressure means after completion of injection by the primary pressure means. Molten metal is injected into the clamped mold via a plurality of branched runners by a primary pressure means,
A branch runner base section that is connected to the area where density improvement is desired is selected, and a pressurization path is provided in the middle of this branch runner, where a pouring pool can be secured.
An orifice is provided in the pressure path directed toward the product, and a pressure pin for a secondary pressure means is provided which moves in the branch runner in the same direction as the flow of the molten metal,
A minute gap is formed between the orifice and the pressure pin, thereby enabling a metal seal to be formed,
A die casting manufacturing method for improving the density of a desired part by applying a partial ultra-high pressure, characterized in that pressure is applied by a pressure pin for the secondary pressure means after completion of injection by the primary pressure means. The secondary pressurizing means prevents the pressure from the secondary pressurizing means from being transmitted to the primary pressurizing means device by blocking the basin with a pressurizing pin and creating a metal seal with a minute gap between the orifice and the pressurizing pin, thereby enabling the secondary pressurizing means to apply high pressure to the product portion. This is a die-casting manufacturing method for improving the density of intended portions by applying local ultra-high pressure as described in any one of claims 1 to 4. A die-casting manufacturing method for improving the density of a desired part by applying partial ultra-high pressure, as described in any one of claims 1 to 4, characterized in that a control mechanism is provided to enable time setting for the start time of the secondary pressure means after injection by the primary pressure means is completed. A die casting manufacturing method for improving the density of a desired part by applying local ultra-high pressure, as described in any one of claims 1 to 4, characterized in that the pressure pin of the secondary pressure means attached to the branch runner and its driving pressure cylinder are set on either the fixed mold side or the movable mold side of the mold. a primary pressurizing means for injecting molten metal into a die-casting mold through a plurality of branched runners;
a secondary pressurizing means for selecting a part of the branch runners and attaching it to the selected branch runner, and for applying a pressure higher than that of the primary pressurizing means;
a control unit that sets a start time for operating the secondary pressurizing means after the filling of the molten metal product by the primary pressurizing means is completed;
an orifice formed on a pressure path surface of the secondary pressure means;
It consists of
A die casting device using partial ultra-high pressure, characterized in that a metal seal can be formed by leaving a minute gap between the orifice and the pressure pin of the secondary pressure means . a primary pressurizing means for injecting molten metal into a die-casting mold via a plurality of branch runners and a newly installed branch runner connected to a portion where density improvement is desired;
a secondary pressurizing means attached to the new branch runner and capable of applying a pressure higher than that of the primary pressurizing means;
a control mechanism for setting a start time for operating the secondary pressurizing means after the completion of filling of the molten metal product by the primary pressurizing means;
an orifice formed on a pressure path surface of the secondary pressure means;
It consists of
A die casting device using partial ultra-high pressure, characterized in that a metal seal can be formed by leaving a minute gap between the orifice and the pressure pin of the secondary pressure means . a primary pressurizing means for injecting molten metal into a die-casting mold via a single branch runner and a newly installed branch runner connected to a portion where density improvement is desired;
a secondary pressurizing means attached to the new branch runner and capable of applying a pressure higher than that of the primary pressurizing means;
a control mechanism for setting a start time for operating the secondary pressurizing means after the completion of filling of the molten metal product by the primary pressurizing means;
an orifice formed on a pressure path surface of the secondary pressure means;
It consists of
A die casting device using partial ultra-high pressure, characterized in that a metal seal can be formed by leaving a minute gap between the orifice and the pressure pin of the secondary pressure means . a primary pressurizing means for injecting molten metal into a die-casting mold through a plurality of branched runners;
a secondary pressurizing means for selecting a diverter base runner located before a branch runner that is connected to a portion where density improvement is desired, and for attaching the selected diverter base runner to the runner so as to be able to apply a pressure higher than that of the primary pressurizing means;
a control unit that sets a start time for operating the secondary pressurizing means after the filling of the molten metal product by the primary pressurizing means is completed;
an orifice formed on a pressure path surface of the secondary pressure means;
It consists of
A die casting device using partial ultra-high pressure, characterized in that a metal seal can be formed by leaving a minute gap between the orifice and the pressure pin of the secondary pressure means . 12. The partial ultra-high pressure die casting apparatus according to claim 8, wherein the secondary pressure means comprises a pressure pin that moves on the parting line, i.e., the contact surface, of the fixed die and the movable die. 12. The die casting apparatus using partial ultra-high pressure according to claim 8, wherein the secondary pressure means is provided so as to be capable of applying pressure in the same direction as the mold clamping direction.