JP2000288713A - Vacuum die casting apparatus and method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the sufficient degree of vacuum in a cavity by disposing a fixed die, movable die shiftable in a first direction and a sealing block to the retreated part of a slide core shiftable to a second direction different to the first direction with respect to the fixed die and the movable die, and abutted on the fixed die and the movable die. SOLUTION: A sealed space containing a cavity 51 and a shifting space of the slide core 8 is formed with the fixed die 1, movable die 2 and sealing block 11, and gas in the cavity is exhausted from an exhaust path in the cavity part with a vacuum pump and also, after exhausting the gas in the cavity from the gas exhaust path 55 in the sliding core part communicated with the sealed space with the vacuum pump, molten metal is poured into the cavity 51 to form a die casting product. A gas exhaust path is arranged to the retreated part of the slide core 8, too, and the gas in the sealed space formed with the fixed die 1, movable die 2 and sealing block 11 can be exhausted in a short time by exhausting with the vacuum pump, and the invasion of the gas from the outer part can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum die casting apparatus and a die casting method for forming a high quality die cast product.

[0002]

2. Description of the Related Art A conventional vacuum die casting apparatus is provided with an exhaust passage communicating with a cavity and a vacuum pump in order to reduce the amount of gas in a product, and discharges gas in the cavity using the vacuum pump. After vacuuming, a metal such as aluminum is filled into the cavity of the mold to obtain a product.

However, when the slide core is provided, there is a gap between the slide core and the fixed mold and the movable mold, so that gas enters into the cavity through the gap, and a sufficient degree of vacuum is obtained. However, there is a problem that the amount of gas in the product is increased and the quality of the die-cast product is deteriorated.

[0004]

SUMMARY OF THE INVENTION In view of the above situation, according to the present invention, by providing a slide core, gas enters into the cavity from a gap between the slide core and the fixed and movable molds, so An object of the present invention is to provide a vacuum die casting apparatus and a vacuum die casting method which solve the problem that a high degree of vacuum cannot be obtained and the amount of gas in a product increases.

[0005]

In order to solve the above-mentioned problems, a vacuum die casting apparatus according to the present invention comprises at least a fixed die, a movable die that can move in contact with the fixed die in a first direction, and The fixed type or the movable type comprises a slide core movable in a second direction different from the first direction and abutting on the fixed type and the movable type, wherein the fixed type, the movable type, And a cavity exhaust passage that forms a cavity with the slide core and communicates with the cavity, and a vacuum die casting apparatus that exhausts the gas in the cavity from the cavity exhaust passage by a vacuum pump. This is a vacuum die casting apparatus that employs the disposition of. Further, the vacuum die casting apparatus of the present invention further comprises a slide core portion exhaust passage communicating with a space formed by the fixed type, the movable type, the slide core and the sealing block, and a vacuum pump for retreating the slide core. This is a vacuum die casting apparatus that employs discharging.

According to another aspect of the present invention, there is provided a vacuum die casting method, wherein a cavity is formed by at least a fixed mold, a movable mold and a slide core, and a cavity exhaust passage communicates with the cavity. After exhausting the gas in the cavity from the exhaust passage by a vacuum pump, in the vacuum die casting method of closing the cavity portion exhaust passage and injecting a molten metal into the cavity to form a die cast product, the fixed die, the movable die and The sealing block forms a sealed space including a space for moving the cavity and the slide core, and discharges gas in the cavity from the cavity exhaust passage by a vacuum pump, and also forms a slide space communicating with the sealed space from a slide core exhaust passage. The gas in the sealed space is After issuing a vacuum die casting method employing a molding a die casting by injecting molten metal into said cavity.

[0007] The above structure is effective. That is, by providing the sealing block, the inside of the cavity can be set to a predetermined degree of vacuum, and the gas in the slide core can be discharged at a high speed by exhausting the gas with a vacuum pump. Vacuum degree can be maintained, and even if there is a gap between the slide core and the fixed and movable molds, the vacuum degree does not deteriorate, the amount of gas in the product is reduced, and a vacuum capable of forming high-quality die-cast products A die casting apparatus and a vacuum die casting method can be provided.

By adopting the above-mentioned means, that is, in particular, by providing a sealing block, a sealed space is formed by a fixed type, a movable type, and a sealing block, and the cavity is housed in the space, whereby the inside of the cavity is formed. When the air is evacuated by the vacuum pump, the gas in the sealed space formed by the fixed type, the movable type and the sealing block can be exhausted, and the invasion of gas from the outside can be prevented. Also, by providing an exhaust passage in the retreating part of the slide core and exhausting with a vacuum pump, the gas in the sealed space formed by the fixed type, the movable type and the sealing block can be exhausted in a short time, and the gas from the outside can be discharged. As a result, the degree of vacuum in the cavity during the injection of the molten metal can be ensured, and the amount of gas in the product can be reduced.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. 1 and 2 are schematic cross-sectional views for explaining an apparatus according to an embodiment of the present invention. FIG. 3 is a schematic sectional view showing a state in which the mold shown in FIG. 1 is opened and the slide core is moved.

FIG. 4 is a perspective view showing the shape of a product formed by the present apparatus and method. FIG. 1 shows a cross section of the present apparatus, and FIG. 2 shows a cross section of another part. In FIG.
(101) is fixed on a device base (not shown) by a fixed platen. Reference numeral (102) denotes a movable platen.
−X ′ line direction). The fixed mold (1) is fixed to the fixed platen (101), while
A movable platen (6), a spacer block (3) and a movable mold (2) are fixed to the movable platen (102).

An injection sleeve (104) is fixed to the fixed platen (101), and a sprue bush (7) is fixed to the fixed mold (1). The injection sleeve (104) and the sprue bush (7) are fixed. 7) is disposed coaxially. An injection plunger (103) is slidably disposed in the injection sleeve (104) and the sprue bush (7). The injection plunger (103) is displaced rightward (X 'direction) in FIG. Molten injection port (107)
Are opened so that molten metal is supplied into the apparatus by a hot water supply apparatus (not shown).

In the movable mold (2), a slide core (8) moves on the movable mold (2) in the vertical direction (YY 'direction) in FIG.
Are slidably disposed. An angle pin (9) is fixed to the fixed mold (1) in an inclined state, and a hole slidable with the angle pin (9) is clear in the slide core (8). Therefore, the slide core (8) moves in the vertical direction (Y-
(Y 'direction).

On the movable mounting plate (6) side, an upper part (4) of the ejector plate and a lower part (5) of the ejector plate are provided.
In conjunction with an ejector pin (10) penetrating through the movable die (2), the space formed by the movable die (2) and the movable mounting plate (6) is moved in the horizontal direction (XX in FIG. 1). ′ Direction), and can be moved by a driving device (not shown).

A cavity (51) formed by the fixed mold (1), the movable mold (2) and the slide core (8).
And the space in the sprue bush (7) are the runner (52) formed by the fixed mold (1) and the movable mold (2).
Are connected by The movable mold (2) has a cavity part exhaust passage (53) penetrating therethrough.
It is connected to the main vacuum pump (105). Between the cavity exhaust passages (53), cut-off pins (12) move in the movable mold (2) in the left-right direction (X-
X 'direction), and the cut-off pin (12) can be opened and closed by controlling the movement of a cut-off pin (12) by a driving device (not shown). The movable block (2) has a sealing block (11) at a position where it does not hinder the movement of the slide core (8).
Is fixed so that gas does not leak out of the apparatus from the slide core retreat space (55) formed by the fixed mold (1), the movable mold (2), the slide core (8) and the sealing block (11). Have been. The movable mold (2) has a slide core portion exhaust passage (54) penetrating therethrough, and a space between the slide core retreat space (55) and the sub vacuum pump (106) is provided.
Connected.

Next, a vacuum die casting method using the above apparatus will be described. Upon receiving the driving force of a driving device (not shown),
The movable platen (102) moves rightward (X 'direction) from the position shown in FIG. 3 to the position shown in FIG. 1, and in conjunction with the movement, the slide core (8) moves the angle pin (9). Under the action, it moves downward (Y 'direction) from the position shown in FIG. 3 to the position shown in FIG. Movement is fixed type (1)
The slide core (8) is held at a predetermined position and is in a mold clamping state. At this time, the injection plunger (103) moves to the right (X 'direction) in FIG. 1 to open the molten metal injection port (107), and the ejector pin (10)
It moves to the left (X direction) and the cut-off pin (1
2) moves rightward (X 'direction) in FIG. 2 to close the cavity exhaust passage (53).

Thereafter, the molten metal is supplied into the injection sleeve (104) and the sprue bush (7) from the molten metal inlet (107) by a hot water supply device (not shown). Thereafter, the injection plunger (103) is connected to the molten metal inlet (10).
In FIG. 1, it is moved leftward (X direction) to a position where the space inside the sprue bush (7) and the sprue bush (7) is shut off, and is temporarily stopped.

Thereafter, the cut-off pin (12) is
It is moved in the middle and left directions (X direction) to open the cavity exhaust passage (53). Thereafter, the main vacuum pump (105) is connected to the cavity (51) and the runner (5).
2) and start evacuation of the gas in the sprue bush (7) through the cavity exhaust passage (53). Then, after detecting by a not-shown timer means that a predetermined time has passed since the time when the cut-off pin (12) has been moved in the left direction (X direction) in FIG. Cut-off pin (12)
Is moved rightward (X 'direction) in FIG. 2 to close the cavity exhaust passage (53). As a result, the evacuation operation through the cavity exhaust passage (53) ends, and the evacuation from the main vacuum pump (105) ends. On the other hand, the sub vacuum pump (106) evacuates the gas in the slide core retreat space (55) through the slide core part exhaust passage (54) from the time when the injection plunger (103) is temporarily stopped, and cuts off the gas. Even after the pin (12) closes the cavity exhaust passage (53), the evacuation of the slide core retraction space (55) is continued, and the slide core (8), the fixed die (1) and the movable die are movable. The evacuation in the cavity (51) is continued from the gap between the surfaces that come into contact with the mold (2).

After detecting that the cut-off pin (12) has blocked the cavity exhaust passage (53) by detecting means (not shown), the injection plunger (10) is turned off.
3), the movement in the left direction (X 'direction) in FIG. 1 is restarted, and the movement is performed to a predetermined position. Thereby, the molten metal in the injection sleeve (104) and the sprue bush (7) is filled into the cavity (51) by the runner (52). At this time, the cavity exhaust passage (53)
Since the metal is in a closed state from the cutoff pin (12), the molten metal does not enter the main vacuum pump (105). On the other hand, since the gap between the contact surfaces of the slide core (8) and the fixed mold (1) and the movable mold (2) is very small, the molten metal may enter the slide core retreat space (55). There is no. In addition, the molten metal has a cavity (5
When the filling is performed in 1), the evacuation of the sub-vacuum pump (106) is extinguished, so that the evacuation from the sub-vacuum pump (106) is terminated after the filling completion time.

Thereafter, when the time until the molten metal filled in the cavity (51) solidifies, the molding of the die-cast product in the cavity (51) is completed. Thereafter, the movable platen (102) moves leftward (X direction) in FIG. 1 under the driving force of a driving device (not shown),
In conjunction with the movement, the slide core (8) is acted on by the angle pin (9) and moves upward (Y direction) in FIG. At that time, the injection plunger (1
03) moves the solidified metal in the left direction (X direction) in FIG. 1 in conjunction with the mold opening operation to a predetermined position, performs an operation of separating the die cast product from the fixed mold (1), and then adds the molten metal. In FIG. 1, up to a position where the entrance (107) is opened.
Move to the right (X 'direction). Thereafter, by receiving a driving force of a driving device (not shown), the upper (4), lower (5) and ejector pins (10) of the ejector plate are moved rightward (X 'direction) in FIG. Cavity (51), runner (5
2) and the die-cast product and other solidified metal formed in a part of the cavity exhaust passage (53) are integrally separated from the movable mold (2). Thereafter, a die casting product and other solidified metals are removed by a removal device (not shown). Thereafter, the ejector plate upper part (4), the ejector plate lower part (5) and the ejector pin (10) are moved leftward (X direction) in FIG.

By performing the above steps in a series, the die casting step is performed, and the process is carried over to the next die casting step. By the way, in the conventional apparatus, the gas flows from the gap between the contact surfaces of the slide core (8) and the fixed mold (1) and the movable mold (2) to maintain the vacuum state in the cavity (51). Because of the difficulty, the amount of gas in the die-cast product is increased, and the quality of the die-cast product is deteriorated. On the other hand, according to the present embodiment, the flow of gas through the gap is suppressed by disposing the sealing block (11), and the slide core formed by disposing the sealing block (11). Since a high vacuum state can be maintained by evacuating the recessed space (55), the amount of gas in the die-cast product is reduced, and the die-cast product (1) shown in FIG.
It is characterized in that the quality of 10) can be improved.

The present invention is, of course, not limited to the above-described example, but may have various aspects. For example, in the embodiment, the angle pin (9) is used as a means for moving the slide core (8), but another cam mechanism or a hydraulic device may be used. Further, there may be a plurality of slide cores (8). The sealing block (11) may be fixed to the fixed mold (1) instead of the movable mold (2). As long as the slide core portion exhaust passage (54) is connected to the sub vacuum pump (106), the slide core portion exhaust passage (54) may penetrate the fixed mold (1) instead of the movable mold (2). The main vacuum pump (10
5) and the sub-vacuum pump (106) may be a single vacuum pump if a distribution means is added. In order to obtain a higher degree of vacuum, a sealing part such as an O-ring may be provided on the surface where the parts contact each other.

[Brief description of the drawings]

FIG. 1 is a schematic view for explaining an apparatus according to an embodiment of the present invention, showing a state immediately after mold clamping.

FIG. 2 is a schematic view for explaining an apparatus according to an embodiment of the present invention, and shows a state in which a cutoff pin opens a slide core portion exhaust passage.

FIG. 3 is a schematic sectional view showing a state in which the mold shown in FIG. 1 is opened and a slide core is moved.

FIG. 4 is a perspective view showing the shape of a product formed by the apparatus and method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Fixed type 2 ... Movable type 3 ... Spacer block 4 ... Upper ejector plate 5 ... Lower ejector plate 6 ... Movable mounting plate 7 ... Sprue bush 8 ... Slide core 9 ... Angle pin 10 ... Ejector pin 11 ... Sealing block 12 ... Cut Off pin 51 cavity 52 runner 53 cavity exhaust passage 54 slide core exhaust passage 55 slide core retreat space 101 fixed platen 102 movable platen 103 injection plunger 104 injection sleeve 105 main vacuum pump 106 Sub vacuum pump 107 ... Molten inlet 110 ... Die-cast product

Claims (3)

[Claims] At least a fixed mold, a movable mold that is in contact with the fixed mold and is movable in a first direction, and a second mold that is different from the first direction with respect to the fixed mold or the movable mold. And a slide core that is movable in the direction and abuts the fixed mold and the movable mold, and the fixed mold, the movable mold, and a cavity portion exhaust passage that forms a cavity with the slide core and communicates with the cavity. In a vacuum die casting apparatus for discharging the gas in the cavity from the cavity exhaust passage by a vacuum pump,
A vacuum die casting apparatus, wherein a sealing block is provided at a receding portion of the slide core. 2. A vacuum pump for retreating a slide core formed by the fixed mold, the movable mold, the slide core, and the sealing block, and a gas in a slide core exhaust passage communicating with the slide core. 2. The vacuum die casting apparatus according to claim 1, wherein the vacuum die casting apparatus discharges by vacuum. 3. A cavity is formed by at least a fixed mold, a movable mold and a slide core, a cavity exhaust passage communicates with the cavity, and the gas in the cavity is exhausted from the cavity exhaust passage by a vacuum pump. In a vacuum die casting method for closing a cavity portion exhaust passage and injecting molten metal into the cavity to form a die cast product, the fixed die, the movable die and the sealing block include a moving space of the cavity and the slide core. A space is formed, and the gas in the cavity is exhausted from the cavity exhaust passage by a vacuum pump, and the gas in the sealed space is exhausted from the slide core exhaust passage communicating with the sealed space by a vacuum pump. Die casting products by pouring molten metal into A vacuum die-casting method, comprising: