JPH0422657B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of installing a ceramic foam filter in a vertically split mold. An object of the present invention is to enable automatic installation of a ceramic foam filter having the shape of a right rectangular thick plate into a vertically divided mold by a machine, thereby facilitating the installation of the ceramic foam filter. The purpose of the filter is to easily and reliably filter out inclusions contained in molten metal, which in turn makes it easier to produce high-quality castings.

(Prior Art) A ceramic foam filter is a porous body made of a refractory material. Ceramic foam filters can be used as filtration media, ie, filters, because their air bubbles are interconnected. Therefore, a ceramic foam filter was attached to the casting mold to filter out inclusions in the molten metal during casting.

A ceramic foam filter attached to a casting mold is molded into that shape from the beginning. That is, a ceramic foam filter for casting cannot be made by first making a large block of porous material and then cutting it to a predetermined size. The reason for this is that ceramic foam filters have a fine net-like structure that extends in three dimensions, so they are easily broken, and therefore it is difficult to cut them into exact dimensions. Also, the reason is, according to the excerpt,
This is because chips remain in the holes, which may clog the holes or get mixed into the filtrate, thereby worsening the filtration effect.

The following method is used to make ceramic foam filters. First, a porous body made of an organic material such as a urethane sponge is used as a base material, which is dipped into a slurry of ceramic powder, then passed between a pair of rolls to adjust the amount of slurry attached, and then dried. It is solidified to form a ceramic coating. Thereafter, this coating is fired to carbonize and burn off the organic material, leaving only the porous ceramic body behind to form a ceramic foam filter.

Ceramic foam filters were sometimes used in the form of disks, but most were used in the form of right-angled rectangular plates. The reason for this is mainly due to the ease of manufacturing; in order to form a disc, the organic material must be punched into a disc, which requires an extra process and makes the manufacturing cost relatively high. Because it will be.

To install a ceramic foam filter in the shape of a right rectangular thick plate into a vertically split mold, make a notch for installing the filter in the runner exposed on the mating surface of the mold, and insert the ceramic foam filter into the notch. It's here. Conventionally, the cuts were made as shown in FIGS. 4 to 6.
To explain this, a vertically split mold is one in which a mold cavity 1 in which a casting is to be made and a runner 3 connected thereto are provided on the mating surface 2 of the split mold, and a part of the runner 3 , a notch 4 was provided by cutting out the runner wall surface. Moreover, all of the cuts were in the shape of a right-angled rectangular thick plate.

In order to install a filter in such a notch 4, manual work has been required. For example, in the case of cut 4 as shown in Fig. 4,
After the divided molds are closed, the ceramic foam filter must be dropped into the runner and installed, so in principle it is not easy to install it using a machine before the molds are combined.
In addition, in the case of FIGS. 5 and 6, it seems easy in principle to insert the ceramic foam filter into the notch 4 by machine, but
In reality, it is not easy. The reason for this is that in order to insert the ceramic foam filter, it is necessary to hold it so that one side of it extends parallel to the mating surface 2, but as mentioned above, the dimensions of the ceramic foam filter must be precisely aligned. This is because it is difficult to align the center in the above-mentioned state and install it on the machine. In addition, ceramic foam filters have uneven surfaces,
This is because, since the filter is made of a brittle material, the surface extending in the insertion direction will be probed by the wall surface of the notch during insertion, resulting in damage to the filter. Thus, in the prior art, it was not possible to mechanically attach the ceramic foam filter into the mold.

Therefore, instead of inserting the ceramic foam filter directly into the notch, a method has been adopted in which the ceramic foam filter is placed in a frame made of refractory or mold material, and then inserted together with the frame into the notch. However, using a frame requires extra materials and steps, which is not at all advantageous.

(Problems to be Solved by the Invention) This invention allows a ceramic foam filter having a right-angled plate shape to be placed directly into a vertically divided mold by a machine without relying on human hands or using a frame. It is what is possible.

(Means for Solving the Problem) The present inventor discovered that although a ceramic foam filter having a right rectangular thick plate shape is a porous body, due to its manufacturing process, a pair of opposing side surfaces However, he noticed that the pores of the filter were blocked, and thought of using this to mechanically lock the ceramic foam filter.
In other words, ceramic foam filters are made by immersing a porous body made of an organic material in a slurry of ceramic powder, then passing it between rolls to squeeze the slurry, and adjusting the amount of slurry deposited. When the material is squeezed by a roll, only the side surface perpendicular to the roll axis is filled with pores. For example, when a ceramic foam filter has the shape of a right-angled slab, one side of the right-angled quadrilateral is oriented parallel to the roll axis, and the adjacent side is oriented perpendicular to the roll axis, and the resulting thick plate is passed between the rolls. The pores are closed only on the pair of opposing sides. Therefore, it was confirmed that the ceramic foam filter could be mechanically locked by suctioning this side surface.

The closed side surface of the pores mentioned above not only means a surface in which all the pores on the side surface are completely closed, but also includes a surface with a small number of open pores. . The reason for this is that even if there are only a small number of open pores, suction can be carried out without greatly hindering vacuum suction.

Furthermore, although ceramic foam filters generally have uneven surfaces and are brittle, the inventor supported a right-angled thick plate-shaped ceramic foam filter on two adjacent sides as described above, and as a result, It has been found that when the triangular plate-shaped portion formed by the other two adjacent side surfaces is held in a protruding state, the mold or filter can be easily inserted into the cut without damaging it by advancing it in that state. This invention was made based on such knowledge.

The present invention uses a ceramic foam filter that is shaped like a right-angled thick plate and has pores closed on a pair of opposing sides, and connects the filter to two adjacent sides.
The side surface is suctioned and locked in the filter installation machine, and the triangular plate-shaped part surrounded by the filter and the other two sides is projected from the installation machine, and in this state, the filter is directed toward the mating surface of the vertically divided mold. advance, make a notch in a part of the runner exposed on the mating surface, match the shape of the notch to the triangular plate-shaped part of the filter that protrudes from the installation machine, and insert the triangular plate-shaped part into the notch. Then, the suction of the installation machine is released, the installation machine is moved away from the mold while leaving the filter in the notch, and the split molds are then closed together.
A method is provided for installing a ceramic foam filter in a vertically segmented mold.

(Example) Hereinafter, an example of the present invention will be described in Figures 1 to 3.
This will be explained based on the diagram.

FIG. 1 schematically shows the method of this invention. In FIG. 1, 1 is a mold cavity in which a casting is to be made, 2 is a mating surface of the mold, 3 is a runner, 4 is a notch, and 5 is a ceramic foam filter. The cut 4 is for inserting a filter 5, and the filter 5 has a thick plate shape of a right-angled quadrilateral.

The notch 4 is the same as a conventional notch in that it is formed by notching a part of the runner along the circumferential direction, but its shape is different. That is, the shape of the notch 4 is not a square plate shape as in the conventional case, but a triangular plate shape. Its shape is such that it can accommodate half of the filter 5, that is, a triangular plate-shaped portion when the filter 5 is divided into two along the diagonal line 52 of the front or back surface 51 that constitutes the widest surface. ing.

The ceramic foam filter 5 has a cutting depth of 4.
Corresponding to the shape of , a triangular plate-shaped portion, that is, a triangular plate-shaped portion when a right-angled quadrilateral is divided into two along the diagonal, is placed with its corners protruding. At this time, due to the manufacturing process, the filter 5 has holes open on the front or back surface 51, and also has holes opened on one of the adjacent sides 53 and 54. The hole is closed on one other side, and one of the remaining two adjacent sides is open and the other is closed. In FIG. 1, the side surface 54 has an open hole, and the side surface 53 has a closed hole. Therefore, by suctioning two adjacent side surfaces 53 and 54, locking can be achieved by suctioning the hole-occluded side. A suction device for this purpose is indicated at 6.

The suction tool 6 is normally incorporated into the filter installation machine 7. The filter installation device 7 is movable toward and away from the mating surface 2 of the mold, and when it comes into close contact with the mating surface 2, the filter installation device 7 is installed so that the protruding triangular plate-shaped portion of the filter 5 held by the suction tool 6 just fits into the notch 4. It is configured. Specifically, the filter 5 is held on the filter installation machine 7 with the diagonal line extending from the vertex on the intersection line of the two side surfaces being sucked by the suction tool 6 protruding from the surface 8 of the filter installation machine 7. has been done. To put it another way, a triangular plate-shaped portion surrounded by two sides other than the two sides being sucked is fixed by the suction tool 6 with the corner protruding first. .

In this invention method, the suction tool 6 incorporated in the filter installation machine 7 sucks and locks the side surface of the triangular plate that is half of the filter 5, and the remaining half is placed on the filter installation machine 7 with the corner first. While holding it in a state protruding from the filter installation machine 7
is advanced toward the mating surface 2 of the mold. The protruding half of the filter 5 is thus inserted into the cutout 4 of the mold. After the half part is inserted, the suction of the filter installation machine 7 is released. Then, the filter 5 is easily removed from the installation machine 7. Therefore, the filter 5 is left in the notch 4 and the filter installation machine 7 is moved away from the mold.

Then, close the rest of the mold. At this time, the other mold part used for closing is provided with a similar cut 4 at the position where the filter 5 protrudes. Therefore, when the molds are closed, the filter 5 will be exactly accommodated across the two notches 4. In this way, the filter 5 is installed in the mold so as to straddle the runner 3 and block the runner. The method of this invention is to install the ceramic foam filter in the mold in this way.

In the explanation so far, in order to facilitate understanding, the shape of the notch 4 has been explained as a triangular plate that is a half of the filter 5. This triangular plate is originally supposed to be a right-angled triangle because the ceramic foam filter is shaped like a right-angled quadrilateral. However, the actual shape of the notch 4 only needs to be approximately a right triangle, and a preferred shape is an acute triangular plate having a slightly smaller apex angle than a right triangle. For example, as shown in FIG. 2, each α between the walls 41 and 42 of the notch 4 is not exactly a right angle, but is an acute angle of 80-88 degrees. By doing this, the filter 5 can be cut 4
When inserted into the filter, the side of the filter 5 will come into strong contact with the entrance of the notch 4.
The filter 5 can be easily fixed within the notch 4.
In addition, a small gap remains at the back of the notch 4, and small pieces and debris of the filter generated during insertion can be collected in the gap, thereby preventing the debris from causing trouble.

Furthermore, on the mating surface 2 of the molds, it is not necessary to provide completely equal cuts in the two divided molds. For example, as shown in FIG. 3, it is desirable to make the cut 4 of one split mold a large and to make the cut 40 of the other split mold b small. The reason is that in this way, when the filter is inserted into the notch 4 of the split type a, the center of gravity of the filter will be located within the notch 4, and the filter will be held stably, reducing the risk of the filter falling. Because it will disappear. Furthermore, it is desirable to provide a slight extra notch in the corner portion 43 of the notch 4. In addition, in FIGS. 2 and 3, the position occupied by the inserted ceramic foam filter 5 is shown by a dotted line.

Furthermore, in the notch 4, the height of the corner portion in the portion that contacts the front or back surface of the ceramic foam filter may be made smaller.
The corner portion is the portion shown with vertical and horizontal lines in FIG. In this way, it is advantageous to make the corner portion narrower toward the tip because the tip of the filter 5 is strongly locked at the back of the notch when the filter 5 is inserted.

The filter setting machine used in the method of this invention can be used by making slight modifications to the device conventionally called a core setter and used for attaching cores to vertically split molds. That is, it is sufficient to attach a part to accommodate only the triangular plate-shaped portion surrounded by the two adjacent side surfaces of the ceramic foam filter, which is in the shape of a thick plate of a right angled quadrilateral, by suction. Therefore, in a workshop that already has a core setter, it is possible to immediately implement the method of the present invention using it.

(Effects of the Invention) According to the method of the invention, since a right-angled thick plate-shaped ceramic foam filter is used, it is easier to manufacture and can be obtained at a lower cost than the conventional ceramic foam filter. Therefore, it can be carried out industrially advantageously. In addition, a ceramic foam filter that is shaped like a right-angled thick plate and has pores closed on a pair of opposing sides is used, and the filter is sucked from two adjacent sides. Because of this, one of the two sides is always a side with a closed hole, so unlike when suction is applied to two opposing sides, it is necessary to select the side with a closed hole for installation. Therefore, the filter can be easily locked to the filter installation machine. Moreover, since the locking is based on suction, the filter can be locked securely without damaging it. Furthermore, when the filter is locked in this way, the triangular plate-shaped part surrounded by the other two sides of the filter can be easily projected from the installation machine, so that the extending direction of the front and back surfaces of the filter is aligned with the plane of the cut. By aligning them, the installation machine can be advanced toward the mold and the protruding triangular plate-shaped portion of the filter can be installed in the notch of the mold. Also, at this time, a notch was made in a part of the runner exposed on the mating surface of the mold, and the shape of the notch was matched to the triangular plate-shaped part of the filter that protruded from the installation machine, so the filter could be locked. By advancing the installation machine directly toward the notch, the protruding triangular plate-shaped portion of the filter can be inserted into the notch from the corner. Therefore, the filter can be easily and reliably inserted into the cut without damaging the filter during insertion. Next, release the suction on the installation machine, so you can avoid damaging the filter.
The machine ensures that the filter remains within the cut. Then move the installation machine away from the mold.
Next, I decided to close the split molds together.
The ceramic foam filter can be easily and reliably attached to the appropriate location of the runner by a machine. As described above, according to the method of the present invention, an inexpensive ceramic foam filter can be easily installed by a machine, and therefore, great industrial benefits can be obtained.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway perspective view of a mold, etc., schematically showing the method of the present invention. FIGS. 2 and 3 are partially cutaway sectional views of a mold used in the method of this invention. FIGS. 4 to 6 are partially cutaway vertical cross-sectional views of conventional molds. In the figure, 1 is a cavity of a mold, 2 is a mating surface of a mold, 3 is a runner, 4 is a notch, 5 is a ceramic foam filter, 6 is a suction tool, and 7 is a filter installation machine.

Claims (1)

[Scope of Claims] 1. A ceramic foam filter that is shaped like a right-angled thick plate and has pores closed on a pair of opposing sides is used, and the filters are placed adjacent to each other. The two sides of the filter are suctioned and locked in the filter installation machine, and the triangular plate-shaped part surrounded by the other two sides of the filter is made to protrude from the installation machine, and in this state, the filter is placed on the mating surfaces of the vertically split mold. Make a notch in a part of the runner exposed on the mating surface, match the shape of the notch with the triangular plate-shaped part of the filter that protrudes from the installation machine, and insert the triangular plate-shaped part into the notch. inserting the mold, and then releasing the suction of the installation machine, leaving the filter in the cut and moving the installation machine away from the mold, and then closing the split molds together.
How to install a ceramic foam filter in a vertically split mold. 2. The method according to claim 1, wherein the apex angle formed by the vertical wall surface of the wall surfaces constituting the cut is an acute angle within the range of 80 to 88 degrees. 3. Among the walls constituting the cut, the horizontal wall surfaces are inclined so that the distance between the horizontal wall surfaces becomes smaller as you go further toward the edge of the horizontal wall surfaces. The method described in Scope 1 or 2. 4. The method according to any one of claims 1 to 3, characterized in that the innermost wall surface of the notch is cut out.