JP2566470B2 - Vertical casting method and device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a vertical casting method and apparatus for injecting a molten metal into a die cavity from directly below to perform casting.

[Conventional technology]

For example, when casting a large amount of precision products such as aluminum automobile parts, casting products with high strength and elongation as well as less air entrapment and no air leaks are created. From the point of obtaining it, it is often a vertical die casting machine.

FIG. 6 is proposed, for example, by the applicant company, and is disclosed in JP-A-63-19.
FIG. 7 is a schematic horizontal cross-sectional view showing the mold and injection device of this vertical casting apparatus disclosed in Japanese Patent Publication No. 2543 by cutting along the line VI-VI in FIG. 7, and FIG. This will be described with reference to FIG. 1. The lower mold 3 is detachably fixed on the fixed platen 2 fixed on the machine base 1, and is also above the fixed platen 2. An upper mold 5 is detachably fixed to a movable platen 4 which moves up and down by a mold clamping cylinder (not shown). A cylindrical fixed sleeve 6 is fitted in the sleeve hole 2a of the fixed platen 2, and an injection sleeve 7 supported on the injection device main body side (not shown) can be freely inserted into and removed from the inner hole of the fixed sleeve 6. Has been inserted. A plunger tip 8a, which is the head of a plunger 8 that is vertically moved by an injection cylinder (not shown), is slidably fitted in the inner hole of the injection sleeve 7, and the molten metal 9 is contained in the injection sleeve 7. Has been injected.

Reference numeral 10 is a cavity having the same shape as the product, which is formed in an H-shaped cross section and has a rectangular shape in a plan view, and a part of which faces the lower mold 3 and most of which is the upper mold 5. Is formed to face the cavity 10 and the injection sleeve 7.
The inner hole is communicated with a passage 11 having the same diameter as the inner hole and a passage 12 formed on the upper mold side by branching into three sections.
A column-shaped hot water pool 13 is formed above the passage 11, and a lower end of the hot water pool 13 is exposed to a pressure pin 14 driven by a pressure cylinder (not shown) to move up and down. By lowering this into the molten metal pool 13, the molten metal 9 injected from the injection sleeve 7 into the cavity 10 is pressurized. Also, above the cavity 10,
A plurality of extruding pins 15 that are driven by an extruding cylinder (not shown) to move up and down are provided at four corners of the cavity 10. By lowering the extruding pins 15, the molten metal 9 in the cavity 10 is solidified and formed. Configured to extrude the product.

With the above configuration, the injection sleeve 7 into which the molten metal 9 has been poured while being pulled out of the fixed sleeve 6 and tilted is erected as shown in the figure and inserted into the fixed sleeve 6, and the injection cylinder When the plunger tip 8a is moved forward with, the molten metal 9 pushed by the plunger tip 6a
Is injection-filled into the cavity 10 through the passages 11 and 12. When the molten metal 9 in the cavity 10 is solidified and cooled,
Since the movable platen 4 rises and the movable mold 5 holding the product rises and the mold is opened, an extrusion pin by an extrusion cylinder is used.
The product in the cavity 10 is extruded from the movable mold 5 by the lowering of 15.

When injecting the molten metal 9 in such a vertical casting method, the cavity 9 is filled with the molten metal 9 and then the plunger tip 8a is further advanced to pressurize the molten metal 9, but with the passage of time, the injection sleeve 7 The molten metal 9 in contact with the inner wall is cooled and solidified, and the pressure applied to the molten metal 9 lowers to make it difficult to replenish the molten metal 9 corresponding to the solidification shrinkage of the molten metal 9 in the cavity 10. Become. Therefore, in this apparatus, a molten metal reservoir 13 is provided in the middle of the molten metal passages 11 and 12, and a pressurizing pin 14 enters the molten metal reservoir 13 and pushes away the molten metal 9 in correspondence with the solidification contraction timing of the molten metal 9. Since the so-called feeder action occurs, it is possible to prevent shrinkage cavities in the product.

[Problems to be Solved by the Invention]

However, in such a conventional vertical casting method and apparatus, only one pressure pin 14 is provided in the center of the product in the cavity 10, and the distance from the pressure pin 14 to the end of the product is large. However, there is a problem that the product is distorted due to insufficient pressure transmission and a satisfactory effect cannot be expected, and that the effect of the feeder is small. In particular, when a sand core or other storage core is used as the core, the product size is difficult to obtain.

The present invention has been made in view of the above points, and an object thereof is to provide a vertical casting method and apparatus capable of uniformizing the pressure transmission to the molten metal in the cavity at the time of injection filling of the molten metal. There is.

[Means for solving the problem]

In order to achieve such an object, according to the present invention, as a vertical casting method, a die is divided into an upper die, a middle die and a lower die, and the molten metal in the lower die side injection sleeve is lifted up by a plunger tip. The horizontal passages provided on the die matching surface between the upper end of the lower die and the lower end of the middle die, a plurality of vertical passages communicating with the horizontal passages, and the lower end of the upper die and the upper end of the middle die communicating with the vertical passages. Injecting and filling into the cavity through a plurality of horizontal passages provided symmetrically with respect to the cavity on the die-matching surface portion with and at the end of the injection filling, above the vertical passages. After pressing the pressure pin into the provided pool and raising the molten metal in the cavity, the upper mold is lifted with the middle mold to open the mold between the lower mold and Lower the pressure pin further to the top of the vertical passage. We adopted a method in which the solidified material in the path was cut and dropped, and then the middle mold was lowered to open between the upper mold and the product in the cavity was pushed out. It is a thing. Also, as a vertical casting device, the mold is composed of a lower mold fixed to a fixed platen, an upper mold fixed to a movable platen above the fixed platen, and a vertical mold located between the lower mold and the upper mold. It is divided into a movably supported middle die, and communicates with an inner hole of an injection sleeve which is formed in a die mating surface portion between the upper end of the lower die and a lower end of the middle die and is inserted into the lower die from below through a molten metal passage. Horizontal passages, a plurality of vertical passages formed in the middle die and communicating with the horizontal passages, and cavities provided between the upper die and the middle die on the die mating surface portion between the lower end of the upper die and the upper end of the middle die. A horizontal passage that is formed symmetrically with respect to each other and communicates with each of the vertical passages; a plurality of basins formed in the upper mold above the vertical passages; Inserted in a freely insertable and removable manner, the hot water pool and vertical passage A plurality of pressure pins also arrows ゝ smaller than the gate end, the molten metal in the cavity is provided with a extrusion extruded pin from the upper mold a product obtained by solidifying.

[Action]

The upper, middle, and lower three-stage molds are clamped, the injection sleeve filled with the molten metal is inserted into the fixed mold, and then the plunger tip moves forward. And is injected and filled into the cavity through a plurality of vertical passages of the middle die and a plurality of horizontal passages of the upper die. At the final stage of injection filling, the pressurizing pin descends and enters the molten metal pool, and the molten metal is pushed away, so that the molten metal in the cavity acts as a molten metal. When the molten metal in the cavity solidifies and cools, the movable platen rises and the upper mold holding the product rises along with the middle mold to open the mold, so the pressure pin further descends to form a vertical passage. Upon entering, the solidified material in the passage is cut from the thin portion around the pressure pin and falls. After that, the middle die is lowered, and the product in the cavity is extruded from the upper die by the lowering of the extrusion pin by the extrusion cylinder.

When the molten metal is injected in such a vertical casting method, the cavity is filled with the molten metal, and then the plunger tip is further advanced to pressurize the molten metal. At this time, a plurality of pressure pins move forward together and enter into each pool to generate a riser action.However, since the melt enters the pool directly below, the press pins should push the hot melt. And, enough feeder is done. Further, since the plurality of pools and the plurality of locations of the cavity are connected by a short molten metal passage, uniform feeding is performed to each location of the cavity.

〔Example〕

1 to 5 show an embodiment of a vertical casting apparatus according to the present invention shown for explaining a vertical casting method according to the present invention, and FIG. 1 shows a die and an injection apparatus thereof as a second embodiment. I-I in the figure
2 is a schematic vertical cross-sectional view, and FIG. 3, FIG. 4 and FIG. 5 are schematic vertical cross-sectional views of a mold and an injection device for explaining the operation. It is a figure. In the figure, a fixed platen 2 fixed on a machine base 1
Above, the lower mold 20 of the mold divided into the upper middle and lower three
Is detachably fixed to the movable platen 4, which is above the fixed platen 2 and moves up and down by a mold clamping cylinder (not shown). 21 is detachably fixed. A cylindrical fixed sleeve 6 is fitted in the sleeve hole 2a of the fixed platen 2, and an injection sleeve 7 supported on the injection device main body side (not shown) can be freely inserted into and removed from the inner hole of the fixed sleeve 6. Has been inserted. A plunger tip 8a, which is the head of a plunger 8 that moves up and down when driven by an injection cylinder (not shown), is slidably fitted in the inner hole of the injection sleeve 7, and 9 is the fixed sleeve. It is the molten metal injected above the plunger tip 8a in a state of being pulled out from 6 and tilted.

Between the upper mold 21 and the lower mold 20, a middle mold 22 of the upper, middle, and lower divided molds is provided movably supported by a side cylinder device (not shown). By lowering the movable platen 4, these molds 20, 21,
22 is crimped and clamped. Lower mold
A horizontal passage 23, which communicates with the inner hole of the injection sleeve 7 through the molten metal passage 11, is formed at the upper end of 20.
In the center of the upper mold 21, a cavity 10 as a space having the same shape as the product, which is formed in an H-shaped cross section and is rectangular in a plan view, is partially exposed to the middle mold 22. It is formed so as to face the upper mold 21. Furthermore, the mid-size 22 has a horizontal passage.
A plurality of vertical passages 24 that communicate with 23 and taper so as to have a smaller diameter toward the upper side are formed in the cavity 10.
Are provided close to the four corners of each of these vertical passages.
Above the 24, a plurality of cylindrical hot water pools 25, which communicate with these, are provided at the lower end of the upper mold 21. Further, at the lower end of the upper mold 21, a plurality of horizontal passages 26 that communicate the respective basins 25 with the cavities 10 are provided in a symmetrical manner with respect to the cavities 10. Here, this bilateral symmetry means not only a bilaterally symmetric state in the strict sense such that the left and right shapes and dimensions are not slightly different, but it is almost bilaterally symmetric or roughly bilaterally symmetric. Contains.
This is done so that the molten metal 9 can enter the cavity 10 from the left and right at approximately the same time or substantially at the same time.

Each of the pools 25 is formed with a diameter slightly smaller than the diameter of the pool 25 and the diameter of the gate 24a formed at the upper end of the vertical passage 24, and is driven by a pressure cylinder (not shown) to move up and down. The lower end of the molten metal 27 is inserted and removed, and the molten metal 9 in the pool 24 is moved into the pool 24.
Is pressed to process the molten metal 9 injected from the injection sleeve 7 into the cavity 10, and further descends to enter into the gate 24a of the vertical passage 24, so that the solidified material in the passage is pushed to be cut and dropped. Is configured. In addition, above the cavity 10, there are provided a plurality of extrusion pins 15 which are driven by an extruding cylinder (not shown) and are moved up and down at the four corners of the cavity 10. The molten metal 9 is solidified and extruded.

A vertical casting method performed using the vertical casting apparatus configured as described above will be described. The molten metal 9 is poured into the injection sleeve 7 which is pulled out of the fixed sleeve 6 and tilted, and the injection sleeve 7 stands up as shown in the drawing and is inserted into the fixed sleeve 6. Then, when the plunger tip 8a is advanced by the injection cylinder, the molten metal 9 pushed by the plunger tip 8a goes up through the molten metal passage 11 and the horizontal passage 23 and then is divided into a plurality of vertical passages 24 to rise to the pool. It is injected and filled into the cavity 10 through 25 and the horizontal passage 26.

At the end of this injection filling, the molten tip 9 in the cavity 10 is pressurized by the continuously rising plunger tip 8a, and the pressurizing cylinder is actuated to move the pressurizing pin 27 into the sump 25.
The molten metal 9 inside the cavity 10 is pushed down because it enters the inside and descends before the gate 24a and pushes away the molten metal 9 inside the pool 25.
Is further pressurized by this feeder action and spreads to every corner of the cavity 10. In this case, when the molten metal 9 enters the molten metal pool 25 from directly below, the molten metal 9 having a high temperature in the central portion of the vertical passage 24 is accumulated and the pressurizing pin 27 pushes the high temperature portion of the molten metal 9, so that the injection is performed. The air entrained in the air collects in the upper part of the basin 24 and prevents the formation of cavities in the product. The pressurizing pin 27 may be lowered into the gate 24a at the time of feeding, and in this case, a thin cylindrical solidified material is formed around the inserting portion of the pressurizing pin 27 inside the gate 24a. When the molten metal 9 is injected, the horizontal passage 26 extending from the pool 24 to the cavity 10 is short and has a small passage resistance, and is connected to a plurality of locations of the cavity 10 in a symmetrical manner. A uniform feeder action works on the spot.

When the molten metal 9 in the cavity 10 is solidified and cooled, the movable platen 4 rises and the plunger tip 8a further rises, and as shown in FIG. 3, the molten metal 9 solidifies to form a product 28. Then, the upper mold 21 and the middle mold 22, which hold the solidified material 29 that solidifies in the passages 11, 23, 24 and is extruded by the plunger tip 8a, are lifted and opened. After the mold is opened, the pressure pin 27 further descends and enters the gate 24a at the upper end of the vertical passage 24 as shown in FIG. 4, so that the solidified substance 29 is cut from the thin portion around the tip of the pressure pin 27. , And is pushed out from the lower end side of the middle mold 22 and falls.

Thereafter, as shown in FIG. 5, the middle die 22 descends, and the extrusion pin 15 descends by the extrusion cylinder, so that the product 28 in the cavity 10 is accompanied by the molten metal pool 25 and the solidified material 30 in the horizontal passage 26. Is extruded from the upper mold 21 and the solidified product 30 is cut from the thin portion to complete one casting operation.

[Effects of the Invention] As is clear from the above description, according to the present invention, as a vertical casting method, a mold is divided into three pieces, an upper die, a middle die, and a lower die, and the molten metal in the lower die side injection sleeve is used. , A horizontal passage provided on the die matching surface portion between the upper end of the lower die and the lower end of the middle die due to the rise of the plunger tip, a plurality of vertical passages provided so as to communicate with the horizontal passage, and the vertical passages. Then, the mixture is injected and filled into the cavity through a plurality of horizontal passages provided symmetrically with respect to the cavity at the mold matching surface portions of the upper mold lower end and the middle mold upper end, and at the end of this injection filling, The pressurizing pin is inserted into the basin provided above the vertical passage to raise the dies, and after the molten metal in the cavity is solidified, the upper die is lifted together with the middle dies so that the space between After opening the mold, lower the pressure pin further. , It enters into the gate provided at the upper end of the vertical passage, cuts and solidifies the solidified material in the passage, and then lowers the middle mold to open the mold between the upper mold and the product in the cavity. Adopting the method of putting out, as a vertical casting device, the mold is a lower mold fixed to the fixed platen, an upper mold fixed to the movable platen above the fixed platen, and these lower mold and upper mold. And an inner hole of an injection sleeve which is formed between the upper and lower ends of the lower mold and which is inserted into the lower mold from below while being divided into a middle mold which is located between and is movably supported vertically. A horizontal passage communicating with a molten metal passage, a plurality of vertical passages formed in the middle die so as to communicate with the horizontal passage, and these upper dies on a die-matching surface portion of the upper die lower end and the middle die upper end. Symmetric with respect to the cavity provided between the Horizontal passages formed in such a manner as to communicate with the vertical passages, a plurality of basins formed in the upper mold above the vertical passages, and insertable and removable into the basins. By providing a plurality of pressurizing pins having a diameter slightly smaller than the gate of the hot water pool and the upper end of the vertical passage, and an extruding pin for extruding the product obtained by solidifying the molten metal in the cavity from the upper mold, At the final stage of injection and filling of molten metal into each cavity, the pressurizing pin enters the molten metal pool and pushes away the molten metal to pressurize the molten metal in the cavity. The hot molten metal enters from directly below and accumulates, and the air trapped during the flow of the passage collects at the top by setting the height of the pool to an appropriate level, so that the formation of cavities due to gas generated in the product is prevented. In That. Further, since the pressurizing pin pushes the high temperature portion at the center of the vertical passage of the molten metal, sufficient feeding is performed, the amount of shrinkage cavities generated in the product is significantly reduced, and the quality of the cast product is improved. Further, since the pressurizing pin, the molten metal reservoir, and a plurality of molten metal passages toward the cavity are provided, and the molten metal passages are short and provided symmetrically with respect to the cavity, the passage resistance is small and the molten metal Pressurization is possible, and the molten metal in the cavity acts uniformly at each location, and the core and other deformations are small, resulting in a product with high dimensional accuracy and improved casting quality. To do. Further, since the solidified material in the molten metal passage can be cut and extruded by using the pressure pin, workability is improved.

[Brief description of drawings]

1 to 5 show an embodiment of a vertical casting apparatus according to the present invention shown for explaining a vertical casting method according to the present invention, and FIG. 1 shows a die and an injection apparatus thereof as a second embodiment. FIG. 2 is a schematic cross-sectional view cut along the line I-I of FIG. 2, FIG. 2 is a schematic vertical cross-sectional view of the same, and FIGS. 3, 4, and 5 are a mold and an injection device shown for explaining the operation. FIG. 6 is a schematic vertical sectional view of FIG. 6, and FIG. 6 shows a mold and an injection device of a conventional vertical casting apparatus of FIG.
FIG. 7 is a schematic horizontal sectional view cut along the line VI-VI, and FIG. 7 is a schematic vertical sectional view thereof. 2 ... Fixed platen, 4 ... Movable platen, 7 ... Injection sleeve, 8a ... Plunger tip, 9 ... Molten metal, 10 ...
… Cavity, 15 …… Extrusion pin, 20 …… Lower mold, 21 …… Upper mold, 22 …… Middle mold, 23 …… Horizontal passage, 24 …… Vertical passage, 24a …… Gate, 25 …… Bath , 26 …… Horizontal passage, 27 …… Pressure pin, 28 …… Product, 29 …… Solidified material.

Claims (2)

(57) [Claims] 1. A mold is divided into an upper mold, a middle mold, and a lower mold,
A horizontal passage provided for the molten metal in the lower die injection sleeve on the die mating surface portion between the upper end of the lower die and the lower end of the middle die by raising the plunger tip, and a plurality of vertical passages provided in communication with the horizontal passage. And a plurality of horizontal passages which are connected to these vertical passages and are provided symmetrically with respect to the cavity on the die matching surface portion between the lower end of the upper die and the upper end of the middle die for injection filling. Together with this, at the end of this injection filling, a pressurizing pin is introduced into the pool of the water provided above each of the vertical passages to carry out the rising, and after the molten metal in the cavity is solidified, the upper mold is After the mold is opened between the lower mold by raising it together with the middle mold, the pressurizing pin is further lowered to enter into the gate provided at the upper end portion of the vertical passage so that the solidified substance in the passage is solidified. Cut and drop, and after that, Lowers the serial middle- and mold opening between the upper mold, the vertical casting method characterized by extruding the product in the cavity. 2. A lower mold fixed to a fixed platen, an upper mold fixed to a movable platen above the fixed platen, and a mold located between the lower mold and the upper mold so as to be movable up and down. A horizontal passage that is divided into a supported middle die and that communicates via an inner hole of an injection sleeve that is formed in the die mating surface portion between the upper end of the lower die and the lower end of the middle die and is inserted into the lower die from below via a molten metal passage. And a plurality of vertical passages formed in the middle die and communicating with the horizontal passages, and right and left with respect to the cavities provided between the upper die and the middle die on the die mating face portion of the upper die lower end and the middle die upper end. Horizontal passages that are formed symmetrically and communicate with the vertical passages, a plurality of basins formed in the upper mold above the vertical passages, and can be inserted into and removed from the basins. Inserted into the pool at the upper end of the pool and the vertical passage A plurality of pressure pins also arrows ゝ smaller than, vertical casting apparatus characterized by melt provided and extrusion extruded pin from the upper mold a product obtained by solidifying in the cavity.