JPH02290644A - Production of mold device, and mold device and heat resistant molten metal permeable sheet-like separator - Google Patents

Abstract

PURPOSE:To prevent collapse of a jaw part in a formed mold and to smoothly manufacture a casting product by inserting the specific shape of heat resistant molten metal permeable separator into groove arranged near pattern part for casting product in runner pattern part of the pattern. CONSTITUTION:The wooden pattern 1 is fixed to a surface plate 2 and the groove 3 is formed near the pattern part 1a for product side in the runner pattern part 1b. As the heat resistant molten metal permeable sheet-like separator 4, the separator having the height as same as height of the runner pattern part 1b and forming the width wider than width of the runner pattern part 1b is prepared. Intermediate face part 4a in the separator 4 is inserted into the above groove 3 and both side face part 4b are made to project toward outside from both side faces in the runner pattern part 1b and folded by bending to far direction from the pattern part 1a for casting product. A casting flask 5 is set on outer circumference of the wooden pattern 1 and molding sand is packed into the space and hardened. This molding sand forming body 7 is turned over and the wooden pattern 1 on upper face is pulled out. Then, the circumferential wall of the forming body is not broke and not collapsed to obtain the casting device for the product having the prescribed shape.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing a molding device, a molding device, and a heat-resistant and water-permeable sheet separator.

[Conventional technology]

Conventionally, in castings consisting of an upper mold and a lower mold, in order to install a heat-resistant porous sheet that perpendicularly crosses the runner formed between the upper mold and lower mold, the upper mold and the lower mold are separated. Insert the upper and lower sides of the sheet into the upper and lower cutouts, and insert the upper and lower side parts of the sheet into the upper and lower cutouts at positions facing each other. The mold device was manufactured by setting the sheet across the road, but when setting it up, the lower side of the sheet was inserted into the cutout provided on the cutting surface of the lower mold, and the lower surface of the upper mold was inserted. It is extremely ugly to fit the upper side part into the facing cutout provided in the. In order to eliminate this inconvenience, the applicant previously filed a patent application No. 63-278475 by making a cutout in the model, inserting a heat-resistant porous sheet into the cutout, and from this state, inserting a heat-resistant porous sheet into the cutout. After filling the internal space with casting sand and hardening the entire model, the model is turned over and pulled out to form a space for product casting that opens to the end side and a concave runner connected to the space. A mold consisting of an upper mold or a lower mold whose central surface crosses the runner at a predetermined location, and whose three side surfaces, both sides and the lower side, are embedded and fixed in the casting sand of the forming mold. We propose to manufacture a molding device according to the above-mentioned method of manufacturing a molding device, in which cuts are formed directly in the cutouts of the upper and lower molds of the above-mentioned conventional mold, and a perforated sheet is inserted across these cutouts. Removed the hassle.

[Problem to be solved by the invention]

In the production of the perforated sheet-embedded mold device disclosed in the above-mentioned application, in order to make the perforated sheet act as a separator, the porous sheet is buried and fixed near the end face opening into the product casting space at one end of the runner. When a product is manufactured, the thickness of the casting sand between the porous sheet and the space on the three sides of the buried surface becomes thinner, so when casting, the molten metal is injected into the space through a runner. Due to the force of the inflowing molten metal, the casting sand in this area tends to crumble due to shock and vibration, and especially when raw pig iron sand is used, it is extremely easy to crumble, resulting in a large loss in the production of gj making equipment with a specified shape. In order to prevent this inconvenience as much as possible, the applicant proposed a casting separator with sloped sides on both sides of the mold, as proposed in the previously filed Utility Application No. 139763/1983. The separator is set near one end on the side of the product casting space of the runner with its three side surfaces buried in casting sand, and the both side surface portions of the separator are bent and tilted in a direction away from the space side, and set. A casting sand wall between both side surfaces of the separator and the space is formed into a tapered thick part to prevent the wall from collapsing as much as possible.

However, when manufacturing a casting device by using the previously proposed porous sheet-like separator and burying its three sides in hook sand near the product casting space of the upper mold or lower mold, it is necessary to There is a risk that the following inconveniences may occur when using the production mold apparatus.

That is, in the manufacturing process, as shown in FIGS. 10 and 11, the porous sheet separator A is inserted into the trough C of the runner b1 of the model B at its center surface a1, and its both side surfaces a2+az and the lower side surface portion a of the model B are installed so as to protrude outward from both side surfaces and the upper surface of each of the runners b+ and b+, and then a casting flask D is installed surrounding the outer periphery of the mold B. The inside of the mold is filled with casting sand up to the upper end of the flask D, and the entire filled sand is solidified and formed (Fig. 11).Next, after inverting this, model B is pulled out to form the mold as shown in Fig. 12 and As shown in FIG. 13, a concave runner G, which is open to the parting surface side of the gong type E, and a space for product casting in the center and a concave runner G communicating with both sides of the space are formed at the cutout mark, and the porous sheet shape The separator A crosses the concave runner G at its center surface a1, and crosses the mold E at its outer three side surfaces a2 + 82 + as.
A mold device H is manufactured by being embedded and fixed in the casting sand on both sides and the bottom of the concave runner G. By using, as the separator A, the above-mentioned one in which both sides a2 + a3 are inclined, each side side part a
Mold walls e on both sides between 2+82 and product casting space F
+. Since e+ can be made thicker, when pouring molten metal into the space F during the production of cast products, the walls e+, e
However, as shown in Figure 10, when the separator A is set on the model B, its lower side surface a3 protrudes upward from the runner-shaped part b1 of the model B. As shown in Figure 11, there is a gap between the lower side a and the product casting mold part b of the model
The thin wall portion e2 is formed by the received casting sand, especially. If green casting sand is used, the thin wall part e2 is likely to be damaged or collapsed by external forces that are easily applied when the model is subsequently pulled out, and if water glass-added casting sand is used, it will be difficult to harden the thin wall part e2. The carbon dioxide gas used is prevented from flowing into and diffusing into the thin wall portion e2 by the protruding lower side surface portion a3, making it impossible to obtain sufficient hardening of the thin wall portion e2. There is. As clearly shown in FIG. 13, the mold device II obtained in this manner has a bottom surface portion of the opening portion of each concave runner G through which water flows into the product casting space F, that is, a jaw portion. is divided by the lower side surface part a3 of the separator A to be embedded, and the product casting space F and the lower side surface part a3
A thin wall portion e2 is formed between the two. Therefore, when casting a product using the molding device, when the molten metal flows into the space F and fills it, the force of the molten metal flows into the thin wall portion e2. e2 may collapse and a cast product of a predetermined shape may not be obtained, resulting in a loss in production.

[Means to solve the problem]

The present invention provides a method for manufacturing a molding apparatus that further improves the invention and idea proposed above, and includes (a) a heat-resistant hot-water supply in the vicinity of the cast product mold part at one end of the runner mold part of the model; (b) As the heat-resistant and hot water permeable sheet separator, its height is as high as the hot water! ! It is the same depth as the groove provided in the mold part,
(C) The width of the separator should be wider than the width of the runner mold part; At the same time, only the side surface portions thereof are made to protrude outward from both side surfaces of the runner mold portion, and further, installed in a state where they are inclined in a direction away from the product mold portion of the model, (d) the above-mentioned A casting flask is installed around the outer periphery of the model in which the heat-resistant and hot-water permeable sheet-like separator is set, and the inner space of the flask is filled with casting sand up to the upper end of the casting flask, and the filled casting sand body is hardened. ,(
e) The method is characterized in that it consists of inverting the obtained molded sand body and pulling out the model located on the upper surface thereof.

[For production]

As mentioned above, as a heat-resistant and water-permeable sheet separator,
Prepare a piece whose height is the same as the depth of the hole provided in the runner mold part of the model, and whose width is wider than the width of the runner mold part, and use this as the depth of the hole provided in the runner mold part of the model. When inserting the
Since the separator is installed in the model without protruding outward from the upper surface of the runner mold part, when filling the space surrounded by the casting flask on the outer periphery with casting sand, the separator is installed in the runner mold part of the model. The top surface of the mold section is covered with a thick layer of sand protection. After that, the filled casting sand body is consolidated, the obtained casting sand molded body is turned over, and the pattern frame is pulled out, and a product of a predetermined shape with an open upper surface, that is, a parting surface, is formed in the place where the mold was pulled out. A casting space and a concave runner communicating therewith are formed, and the middle surface crosses the entire cross section of the concave runner, and the peripheral parts on both sides are at the same height as the depth of the concave runner. A molding device is obtained in which sheet-like separators are inserted and fixed into the casting sand portions on both sides of the channel, that is, the weir. Since the side surfaces are gradually inclined backward with respect to the front opening end surface of the thirst duct, a tapered thick groove is formed between the product casting space and the sloped side surfaces. A mold wall is formed.

Therefore, this part is prevented from chipping or collapsing due to the flow of molten metal during the production of cast products.In addition to this, the jaws on the lower surface of the runner are separated from the lower side of the conventional separator. By embedding the face part, there is no formation of a thin wall, so a solid jaw part can be cast, which solves the conventional problem of collapse of the thin wall part and prevents the collapse of the jaw part. However, the production of cast products with good stability in a given shape is not stable.

〔Example〕

Next, examples of the present invention will be described.

Figures 1 to 9 show an example of the method for manufacturing the molding device of the present invention. In the drawing, 1 indicates a model with a predetermined shape. The model 1 may be made of any material such as wood, metal, ceramic, or plastic. In the following examples, wooden fJJ
Since the explanation will be given using an example of a product model, a "wooden mold" 87i will be used instead. Mold part 1b
, 1b, consists of base parts 1c, 1c on the sprue side and riser side. The wooden mold 1 is fixed to two flat surface plates with adhesive, and the runner mold part 1b is divided into two near the product mold part 1a side of one end of each runner mold part 1b, A cutout 3 is formed for inserting a heat-resistant and water-permeable sheet separator that reaches two surfaces of the surface plate. It goes without saying that the eraser 3 may be formed in advance by dividing it into two parts at a predetermined point and fixing it to the surface plate 2 with a predetermined width. On the other hand, as shown in the second figure, a separator 4 made of heat-resistant fibers such as high-silicate glass fibers and formed into a porous heat-resistant and hot-water-permeable sheet shape, such as a net shape, has a height equal to that of the wooden mold 1, as shown in the second figure. The height of the runner mold part 1b is the same as that of the runner mold part 1b, and therefore the depth of the groove 3 provided therein is the same, and the width thereof is wider than the width of the runner mold part 1b. As shown in the third figure, the middle surface part 4a is inserted into the inner part 3 of the wooden mold 1, and the both side surface parts 4b are projected outward from both sides of the runner mold part 1b. The mold part 1a for the cast product is bent and tilted in the direction away from the mold part 1a for the cast product. As shown in FIGS. 2(A) and 2(B), before the separator 4 is inserted into the holder 3, its both sides 4b, 4b are bent at a predetermined angle with respect to the intermediate surface 4a. Alternatively, you can bend it after inserting it into the connector. The direction in which the side surfaces 4b, 4b are bent is the direction away from the product mold part 1a of the wooden mold 1.

Further, its inclination angle is, for example, 45° with respect to the intermediate surface portion 4a. Incidentally, the outer ends of the U oblique side surfaces 4b, 4b may be stably installed by abutting on the surface plate 21 with engagement pins 2a, 2a which are not provided protrudingly. Next, a molding sand filling space is provided around the outer periphery of the wooden mold 1, and a molding frame 5 is installed surrounding it, and the molding sand is filled in the space, and the molding mold 5 is filled with molding sand.
The sand is packed until it becomes flush with the upper end surface of the molded sand, and the whole is solidified in this state to obtain a cast sand molded body 7 (FIG. 4). Any type of casting sand can be used, including green casting sand, anti-sand mixed with water glass that hardens with carbon dioxide gas, and hardening furan casting sand. As clearly shown in FIG. 4, a packed layer of casting sand is uniformly formed up to the upper surface of the well 3 of the wooden mold 1. In other words, according to the previously proposed separator, the lower side protrudes above the liquor, so the filling layer is divided and a thin wall is formed between the lower side and the wooden product mold. This eliminates the formation of sand particles, and forms a molded sand body 7 in which the outer circumferential surface of the product mold portion 1a is covered with a uniform filling layer. Therefore, when the casting sand is hardened with carbon dioxide gas, the carbon dioxide gas circulates and diffuses uniformly within the filled casting sand, uniformly hardening the casting sand around the outer periphery of the mold for the product, and causing the molding wall surface to collapse. A molded sand body 7 having a space for a high-quality cast product without any cracks can be obtained. Next, the casting sand molded body 7
Turn it over and pull out the wooden mold 1 placed on the top surface. Even when subjected to external force during this drawing, the molded body peripheral wall does not break or collapse, and a mold device 8 having a product space of a predetermined shape can be obtained. 5, 6, and 7 show the mold device 8 thus obtained. That is, by pulling out the wooden mold 1,
In the trace, there is a predetermined shape open on the upper surface of the sand molded body 7, in the illustrated example, a substantially truncated cone-shaped product yJ manufacturing space 8a, and concave runners 8b on both sides communicating with this 17FJD.
8b is formed, and the product jg of the runner 8b is formed.
The lagoon i8b is located near the opening end face that connects to the J building space 8a.
．． That is, the intermediate surface portion 4a that crosses the entire cross section of the concave space and the slopes on both sides embedded and held in the casting sand of the molded sand body 7 on both sides at h equal to the depth of the runner 8b, that is, the height of the weir. A mold, that is, a mold device 8, is obtained in which the separator 4 consisting of the side portions 4b, 4b is turned on.

That is, according to the method of manufacturing the mold apparatus of the present invention, both inclined side surfaces 4b, 4b of the separator 4 are connected to the concave runner 8b communicating with the product casting space 8a, as shown in FIG. It is advantageous that thick tapered mold wall portions 9, 9 with increased strength are formed between the mold wall surfaces 7a, 7a which extend on both sides of the opening end surface and which define the space 8a, and which are gradually separated from the mold wall surfaces 7a, 7a. First, the proposed proposal was submitted in 1986-13.
In addition to not having the same structure and effect as the molding device of No. 9763, according to the present invention, as clearly shown in FIGS. 5 and 7, the space 8a of both the runners 8b, 8b The bottom wall near the end face on the side that communicates with the
In the space 8a, the strength of the peripheral wall of the space 8a is increased because there is no need to embed the lower side surface in the space 8a as previously proposed. That is, the lower side of the separator proposed earlier is connected to the runner 8b,
There is no possibility that a thin wall portion protrudes downward into the bottom wall of 8b, that is, the space 8a, and a thin wall portion is formed between the lower side surface portion and the space 8a, and therefore, the problem of collapse, which will be described later, associated with this can be solved. Therefore, the mold device S manufactured in this manner is used as a lower mold or an upper mold, and a separately manufactured upper mold or lower mold opposite thereto is stacked to form a mold for producing a casting of a predetermined shape.

In FIG. 8, the above-mentioned molding device 8 is used as a lower mold, and a space 9a for product casting, a sprue system runner 9b, and a riser system runner 9c are formed in the vertically extending center separately manufactured on the upper surface of the lower mold. Upper mold 9
A mold 10 consisting of is shown. In this case, when the upper mold 9 is stacked on the lower mold 8, the open upper surfaces of the concave runners 8b, 8b are closed by the lower surface of the upper mold 9 and form a rectangular shape surrounded by a rectangular wall with a square cross section. A runner is formed, and the upper edge of the intermediate surface portion 8a that crosses the runner 8b of the separator 4 comes into contact with the lower surface of the upper mold 9, and the runner is formed in the intermediate surface portion 8a of the separator 4.
completely traversed. Also, the space 8 of the lower mold
A is combined with the empty 17ff portion 9a of the upper mold to form a product casting space S of a predetermined shape. Using this mold 10, according to a conventional method, molten metal without heating and melting the metal is injected through the sprue system runner 9a, and flows into the upper and lower combined product casting spaces 9a, 9a through the runner 8b. Fill it, then cool it to solidify the molten metal to complete casting, destroy the upper and lower molds, and f! I did not take out the casting P. The casting P taken out from the mold 10 is composed of a cast crystal P1 and runner system solidified parts P2, P2 on both sides of the casting crystal P1 as shown in FIG. System coagulation part I'2. Since the intermediate surface portion 4a of the separator 4 intervenes between P2 and the entire cross section thereof, if the runner system solidified portion P2 is hit on the P2 side with a hammer, the intermediate surface portion 4a
Since the product is divided along the crystallization P1 with almost no surplus solidified portion remaining, subsequent surface treatment of the product is facilitated.

The heat-resistant and water-permeable sheet separator has a protective sheet attached to one side that is flammable or removable with i'ff hot water, as previously proposed, and both sides are reinforced with reinforcing plates. You can also use the

〔Effect of the invention〕

As described above, according to the present invention, the hole provided near the mold part for a cast product of the runner mold part of the model has a height that is the same as the depth of the well, and the runner mold part of the model A state in which an R#4 heat permeable separator having a width wider than the width of the separator is inserted at its intermediate surface, and both side surfaces protruding outward from the separator are inclined so as to move away from the mold for the cast product. Since it is installed in the model, a mold with a strong jaw part is obtained during molding, and the manufactured mold apparatus can be used as an upper mold or a lower mold to prevent the jaw part from collapsing due to pouring. The central part of the proposed separator was inserted into the model, and the three outer sides of the separator were projected not only to both sides of the model but also to the top.7
This method solves the problem of thin walls collapsing in the jaws when using a molding device manufactured by this method, and improves the smooth productivity of molds and cast products. It has the effect of improving the

[Brief explanation of drawings]

1 to 8 show an example of the manufacturing method of the casting device of the present invention, FIG. 1 is a cut side view of a wooden model, and FIG. 2 (A
)(B) is a perspective view of the heat-resistant and water-permeable separator used in the method of the present invention, FIG. 3 is a perspective view of a model in which the separator is installed, and FIG. 4 is a molded body in the casting sand filling process. FIG. 5 is a cut side view of the mold device obtained by removing the model, FIG. 6 is a plan view of the mold device shown in FIG.
The figure is a cross-sectional view taken along the line ■-v■ in Figure 6, FIG. 8 is a cross-sectional view of the mold that overlaps with the upper mold when the molding device is used as a lower mold, and FIG. 9 is a sectional view of the slope of the casting. 10 to 13 show an example of a method for manufacturing a mold device using the previously proposed separator. FIG. 10 is a perspective view of the separator installed on a model, and FIG. 12 is a plan view of the mold apparatus shown in FIG. 11, and FIG. 13 is a cross-sectional view taken along line III in FIG. 12. 1... Model, wooden mold 1b... Runway mold part 3... Spring 4a... Intermediate surface part 6... Casting flask 7b... Jaw part 8a... Product casting space 8b...・Hot water path

Claims (1)

[Claims] 1. (a) A groove for inserting a heat-resistant and hot water-permeable sheet separator is provided near the cast product mold part at one end of the runner mold part of the model, and the separator is placed on a flat plate surface. (b) The heat-resistant and water-permeable sheet-like separator is such that its height is the same as the depth of the groove provided in the runner mold part, and its width is wider than the width of the runner mold part. (c) Insert the intermediate surface of the heat-resistant and water-permeable sheet-like separator into the groove provided in the runner mold part, and insert only the side surfaces of the heat-resistant and hot water permeable sheet separator into the grooves provided in the runner mold part, and (d) The outer periphery of the model in which the heat-resistant and water-permeable sheet-like separator is set as described above; (e) Inverting the obtained molded sand, A method for manufacturing a molding device used as a lower mold or an upper mold, comprising: pulling out the model located on the upper surface. 2. In a mold consisting of an upper mold and a lower mold formed with a product casting space open to the body side and a concave runner opened in communication with the space, at least one of the upper mold and the lower mold is A heat-resistant hot water permeable sheet-like separator is made to cross the entire cross section of the concave runner at a location close to the opening end surface of one end of the concave runner that opens into the space for casting the cast product at its intermediate surface, and A mold device comprising only its side surfaces having the same height as the weir of the runner, which are embedded and fixed in the casting sand portions on both sides of the runner, and are inclined in a direction away from the front opening end surface of the runner. 3. The height is equal to the depth of the groove formed in the runner mold part of the model, the width is wider than the width of the runner mold part, and is inclined at a desired angle with respect to the intermediate surface part, or is later made to be inclined. A heat-resistant and water-permeable sheet separator comprising side portions on both sides.