JPH0636975B2 - Mold release method of casting machine - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold releasing method for reliably and easily releasing a molded product in a casting machine for casting a product having an undercut portion on its outer periphery. .

(Prior Art) Conventionally, in order to obtain a high-quality and high-strength cast product having high dimensional accuracy and excellent casting, a pressure casting method in which pressure is applied to the molten metal in the mold to form and solidify is well known, When the cast product has an undercut portion on the outer surface, a split mold is often used which moves in a stroke-like manner by opening or closing the mold in conjunction with a movable mold. If the cast product is cup-shaped, it tends to remain in the mold on the side with a large mold release resistance, that is, the cup inner mouth restraint side due to mold shrinkage during mold opening after molding and solidification. It is common to provide a mechanism. Therefore, in a vertical casting machine for casting a cast product having a cup shape and an undercut portion on the outer surface by pressure solidification, for example, as shown in FIGS. 7 and 8 of JP-A-61-182868. There is known a device in which a cup opening is directed downward so that a cast product at the time of mold opening is always left under the extrusion mechanism.

(Problems to be Solved by the Invention) However, in the state in which the cup opening portion is directed downward as in the above apparatus, when the runner is provided below to attempt to simplify the apparatus, as shown in FIG. And it is unavoidable to form the sprue 5 at a part of the cup opening end facing the mold split surface of the upper mold 52, and the spouting property becomes poor, or as shown in this example, there are two sprues 53, 53. If this is set, there is a problem that there is no place for gas escape.

On the other hand, with the cup opening facing upward and the opening upper end facing the mold splitting surface of the mold, filling the molten metal from the bottom side of the cup improves the bathing property and allows sufficient gas escape. On the other hand, when the mold is opened, the molded product tends to remain on the upper mold side, which causes a problem of mold release.

(Means for Solving the Problems) In order to solve the problems, the present invention provides a movable mold opening,
Insert a mold release pin that can move back and forth in the direction of stroke movement into the split mold that moves in conjunction with mold closing, and insert the tip of this mold release pin into the opening on the restraining surface of the split mold. In the mold releasing method of the casting machine, in which the position of the mold releasing pin is held while the mold is solidified and solidified and then the mold moves as the mold moves along with the rise of the movable mold to move the stroke. The movable die is linked by a split type inclined hole and a movable type inclined pin fitted in this inclined hole, and a play is provided between the inclined hole and the inclined pin so that there is a time difference after the transition of the movable type. The split type stroke movement is started.

(Function) When the split mold splits and separates from the molded product, the mold release pin remains in contact with the outer surface of the molded product, so that the mold can be easily separated from the molded product, and the fixed position on the fixed mold side is always maintained. However, by providing play between the movable tilt pin and the split mold tilt hole, the movable mold starts to move as the mold is opened. Therefore, the movable mold and the molded product are reliably released.

(Example) The Example of this invention is described based on the accompanying drawing.

FIG. 1 is a vertical cross-sectional view showing the entire vertical casting machine, and FIG. 2 is an operational view of a partial view seen from the II-II direction in FIG.

This vertical casting machine is provided for casting of aluminum by a pressure solidification casting method, and as shown in FIG. 1, an upper die 2 provided on a lower die 1 as a fixed die becomes a movable die and moves vertically. The mold is opened and closed, and the lower mold 1 is provided with a pressing and pushing mechanism 3 at the center thereof.

A lower core 11 is attached to the center of the split surface of the lower mold 1, and a lower block 12 is integrally formed around the lower core 1 to form the lower mold 1.
And the lower core 11,
A split sliding die 4 as a split die is provided on the lower block 12. This split slide die 4 is slidable in the front and back direction of the paper surface of FIG. 1, and guide blocks 13 for guiding this slide are attached to the upper surfaces of both end portions of the lower die 1.

On the other hand, an upper core 21 projecting downward is attached to the split surface of the upper mold 2, and a casting pin 22 having a cooling water passage 23 is integrally formed at the center of the protruding part to mold the upper mold 2. It forms a mating surface.

Therefore, when the lower mold 1, the upper mold 2 and the split sliding mold 4 are matched with each other, as shown in FIG. 1, a pair of left and right cup-shaped cavities 5 and a runner portion 6 for communicating these cup bottom surfaces are formed. Will be. Further, a runner not shown in the drawing is connected to the center of the nanna portion 6 downward, and the molten metal passing through this runner is pressurized by a pressure plunger to fill the cavity.

The pressurizing / extruding mechanism 3 is a pair of pressurizing cylinder units 3 sandwiched between the extruding support plate 31 and the extruding plate 32.
3, 33, a pair of pressurizing pins 34 extending from the cylinder rod of the pressurizing cylinder unit 33 and penetrating the extruding plate 32 in a loose insertion manner to move up and down, and the extruding plate 32.
A plurality of pushing pins 35 attached to the lower die 1 are provided, and the pushing support plate 31 can be moved up and down by a driving device (not shown). Regulated in position.

The above-mentioned pressurizing pin 34 is provided so that its tip faces the molten boss portion at the bottom of the cup so as to directly press the molten metal and press the molten metal.
The pressure cylinder unit 33 causes the pressure cylinder unit 33 to project to a position indicated by a broken line.

As described above, the split slide die 4 is slidable in the front-back direction of the paper surface of FIG. 1, and therefore, as shown in FIG. 2, the inclined hole 41 engaging with the inclined pin 24 protruding from the upper die 2 is formed. The upper mold 2 is configured so as to move in conjunction with the stroke as the upper mold 2 moves up or down. A slight clearance is provided between the inclined pin 24 and the inclined hole 41 as shown in the enlarged view of FIG.

On the other hand, inside the split sliding die 4, a release pin support member 42 is provided.
The mold release pin 43, which penetrates through the mold from the mold release pin support member 42 toward the cavity 5, is configured such that the tip end thereof faces the opening 44 of the restraining surface when the mold is clamped. The release pin support member 42 is held by the engaging portion 45 of the split slide die 4 so as to be movable in the sliding direction by a predetermined distance, and the free space is split and slid by the inclined pin 24 of the upper die 2. It is set to be at least equal to or slightly larger than the interval at which the die 4 moves in the stroke. Further, a cylinder rod of a cylinder unit 46 attached to the lower die 1 is coupled to the release pin support member 42, and further split opening slide of the split slide die 4 is possible via an engaging portion 45. I am trying. The release pin 43 is provided on the split sliding die 4 in both directions.

In the apparatus thus configured, when the cavity 5 shown in FIG. 1 is filled with the molten metal, the gas is easily discharged from the split surfaces of the upper die 2 and the split sliding die 4. Next, the pair of pressurizing cylinder units 33 are driven to press the pressurizing pin 34 directly into the molten metal to solidify it, and the mold opening starts. At this time the second
The cylinder unit 46 shown in the figure does not operate, and therefore, the tip of the release pin 43 remains in contact with the outer surface of the molded product as shown in FIG. Mold release is easily performed, and since the mold release pins 43 are in contact with each other from both directions, the molded product is held at a fixed position on the lower mold 1.

The mold release between the upper mold 2 and the molded product is also performed by the fact that the projection on the outer surface of the molded product is still engaged with the restraining surface of the split slide mold 4 when the upper mold 2 starts to move. The play shown in FIG. 43 and FIG. 3 provides further assurance.
In other words, this play exerts the effect of keeping the outer surface of the split slide die 4 restrained during the initial rising of the upper die 2.

The molded product on the lower mold 1 separated from the upper mold 2 and the split sliding mold 4 in this way is ejected by the extrusion of the extrusion pin 35 by the elevation of the extrusion support plate 31.

Further, even if the opening of the cup-shaped part faces upward, the molded product can always remain on the lower fixed mold, so that the quality of the product is improved and the flexibility of the overall layout is improved. .

(Effect of the Invention) As described above, according to the present invention, the casting machine is configured such that the movable die tilt pin is fitted into the split die tilt hole to move the split die in a stroke in conjunction with the opening of the movable die. In the above, since the play is provided between the tilt hole and the tilt pin so that the split mold can be stroke-moved with a time lag after the transfer of the movable mold, it is possible to securely separate the movable mold while keeping the molded product in the original position. When the mold can be performed and the split mold is subsequently separated from the molded product, the tip of the release pin in the split mold is brought into contact with the outer surface of the molded product, so that the molded product is fixed. Can be held in a fixed position.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing the entire vertical casting machine, FIG. 2 is an operational view of a partial view seen from the direction II-II in FIG. 1, and FIG. 3 is a split sliding type stroke transfer mechanism. And FIG. 4 is a partial view showing a conventional example. In the drawings, 1 is a lower die, 2 is an upper die, 3 is a pressure extrusion mechanism, 4 is a split slide type, 5 is a cavity, 24 is an inclined pin, 34 is a pressure pin, 35 is an extrusion pin, 41 Is an inclined hole, 43 is a release pin, 44 is an opening, 51 is a lower mold, 52
Indicates the upper mold.

Claims (1)

[Claims] 1. A mold releasing pin which is movable in a stroke on a fixed mold in conjunction with opening and closing movements of a movable mold. Casting with the mold facing the opening of the restraining surface of the split mold, and holding the position of the mold release pin during the stroke movement of the split mold due to the mold opening accompanying the rise of the movable mold after the molding and solidification. In the mold releasing method of the machine, the split die and the movable die are interlocked with each other by an inclined hole of the split die and a movable type inclined pin fitted in the inclined hole, and a play is provided between the inclined hole and the inclined pin. A mold releasing method for a casting machine, characterized in that a stroke movement of the split mold is started with a time difference after the moving of the movable mold.