JP2009039777A - Core molding method and core molding device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a core molding method and a core molding device where, by a blow head capable of performing single air blowing or the like, the interference of air or the like is prevented while solving the insufficiency of its filling to respective head parts, thus a plurality of cores with uniform quality can be efficiently molded. <P>SOLUTION: Sand in respective hopper parts of a sand hopper is fed into head members divided into two or more in a blow head at a sand feeding position. The blow head is moved to a sand blowing position, and, by air in an air feeding means provided correspondingly to the respective head parts at the position, the sand in the respective head parts is blown into a plurality of core cavities formed by upper and lower dies, respectively, so as to be filled therein. Thereafter, firing is performed, so as to mold a plurality of cores. The blowing of the air into the respective head parts is performed with a prescribed time difference in such a manner that it is not simultaneously blown into a plurality of the head parts, and further, the firing is performed correspondingly to the blowing and exhausting of the air to the respective head parts. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a core molding method and a core molding apparatus for molding a core as a mold used in casting.

  Conventionally, a core molding apparatus used when molding a core is disclosed in, for example, Patent Document 1. The core molding apparatus includes a sand hopper disposed at an upper portion of a column, a blow head having a blow nozzle disposed at a lower portion of the sand hopper so as to be movable in a horizontal direction, and an upper surface disposed below the interior of the column. And an elevating table on which an upper mold and a lower mold defining the core cavity are arranged, and an air tank for blowing sand in the blow head into the core cavity from the air inlet.

After the sand in the hopper is supplied into the blow head from the sand discharge port provided at the bottom of the sand hopper, the blow head is moved to the position of the lifting table, and air of a predetermined pressure in the air tank is introduced into the air. The core corresponding to the cavity shape is formed by blowing into the blow head from the mouth, filling the core cavity with the sand in the blow head, and then firing the core cavity.
JP-A-9-141389

  However, in such a core molding apparatus, since one type of sand is accommodated in the sand hopper and the air in the blow head is blown into the core cavity, there is one air inlet. Is divided into two parts to define two head parts and take two cores, the volume of the blow head with respect to the air inlet is large and the air pressure is dispersed. As a result, insufficient filling of sand in each head portion is likely to occur, and it is difficult to mold a uniform quality core. In order to compensate for this insufficient sand filling, a method of increasing the air pressure is also conceivable. However, in this case, wear of the mold is accelerated, and the value of the air pressure is naturally limited. Moreover, since one type of sand is stored in the sand hopper, the sand used in the molding apparatus is specified, and the versatility of the molding apparatus is inferior, for example, it becomes difficult to use different sands simultaneously.

  The present invention has been made in view of such circumstances, and its purpose is to eliminate air filling while eliminating insufficient filling of each head portion by a blow head capable of blowing air alone. An object of the present invention is to provide a core molding method and a core molding apparatus that can prevent and efficiently mold a plurality of uniform cores in quality. In addition to the above object, another object is to provide a core molding method and a core molding apparatus that can accommodate a plurality of types of sand in a sand hopper and improve the versatility of the molding apparatus.

  In order to achieve this object, the core molding method according to claim 1 of the present invention supplies sand in the sand hopper to each of the head sections divided into a plurality of blow heads at the sand supply position. The head is moved to the sand blowing position, and the sand in each head part is formed by upper and lower molds by the air of the air supply means provided corresponding to each head part at the position. Each of them is blown and filled, and then fired to form a plurality of cores.

  Further, as described in claim 2, the blowing of the air into each head part is preferably performed with a predetermined time difference so that a plurality of head parts do not become simultaneous. As in the third aspect of the invention, it is preferable to carry out air blowing and exhausting to each head portion.

  The core molding apparatus according to claim 4 is a sand hopper in which predetermined sand is accommodated, and a blow head in which the sand in the sand hopper is supplied into a plurality of head sections partitioned at a sand supply position. Then, the sand in each head part of the blow head is blown and filled into a plurality of core cavities formed by upper and lower molds provided corresponding to each head part by the air at the blowing position. An air supply means.

  The sand hopper preferably has a plurality of hopper portions divided into a plurality corresponding to each head portion of the blow head, as in the invention according to claim 5, The air supply means has an air inlet provided in each head part of the blow head and an air tank connected to the air inlet via an inlet pipe as in the invention described in claim 6. It is preferable.

  According to the first aspect of the present invention, the sand in the sand hopper is supplied into each of the head sections divided into a plurality of blow heads, and air supply means provided corresponding to each head section. Since the air in each head part is blown into and filled in a plurality of core cavities, air can be blown into each head part and exhausted independently. While eliminating the shortage of sand filling inside, interference between each head part and core cavity due to air leakage etc. can be prevented, and a plurality of uniform cores can be formed efficiently. .

  Further, according to the invention described in claim 2, in addition to the effect of the invention described in claim 1, since air is blown into each head part with a predetermined time difference so as not to be simultaneously, Air interference between the head portions and the like can be prevented more reliably.

  According to the invention described in claim 3, in addition to the effect of the invention described in claim 1 or 2, since the firing is performed corresponding to the blowing of air and the exhaust to each head part, each head part The firing time of each core cavity corresponding to the above can be arbitrarily set, and a plurality of cores can be formed more efficiently.

  According to the core molding apparatus of claim 4, the blow head having a plurality of divided head portions to which the sand in the sand hopper is supplied, and the sand in each head portion are divided into a plurality of cores. Since it is equipped with air supply means to blow and fill each cavity, air can be blown into each head part and exhausted independently, while eliminating the insufficient filling of sand into each core cavity, Interference between each head portion and the core cavity due to air leakage or the like can be prevented, and a plurality of uniform cores can be efficiently formed.

  According to the fifth aspect of the present invention, in addition to the effect of the fourth aspect of the invention, the sand hopper has a plurality of hopper portions that are divided into a plurality corresponding to each head portion of the blow head. The versatility of the molding apparatus can be improved, for example, different cores can be molded by accommodating different sand in each hopper.

  According to the invention described in claim 6, in addition to the effect of the invention described in claim 4 or 5, the air supply means includes an air inlet provided in each head portion of the blow head, and each air introduction. Since it has air tanks connected to each port via an inlet pipe, air can be supplied satisfactorily and independently into each head portion via the air inlet port. Can be resolved.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 to 8 show an embodiment of a core molding apparatus according to the present invention, FIG. 1 is a front view showing the overall shape, FIG. 2 is a rear view of the main part, and FIG. 3 is a side view of FIG. 4, FIG. 4 and FIG. 5 are plan views of a sand hopper and a blow head, FIG. 6 is a process diagram showing an example of a core molding method using the molding apparatus, and FIG. 7 and FIG.

  As shown in FIG. 1, the core molding apparatus 1 includes a sand hopper 3 disposed at an upper portion of a column 2, a blow head 4 disposed below the sand hopper 3 so as to be horizontally movable, An air supply means 5 for blowing air into the head 4 and an upper mold 6 and a lower mold 7 disposed below the air supply means 5 are provided.

  The sand hopper 3 is formed in a substantially conical shape with an open top surface having a circular shape in plan view. As shown in FIGS. 2 and 4, the partition plate 8 is fixed at a diameter position inside the sand hopper 3. Hopper portions 3a and 3b are partitioned and circular sand discharge ports 9a and 9b are provided on the bottom walls of the hopper portions 3a and 3b. The sand discharge ports 9a and 9b are opened and closed by the horizontal movement of the shutter 10 (see FIG. 1). And in each hopper part 3a, 3b of this sand hopper 3, sand S, such as RCS (resin coat sand), is supplied from the opening of the upper surface, and is stored (stored). .

  As shown in FIGS. 2 and 5, the blow head 4 has two head portions 4a and 4b formed in a substantially rectangular shape in plan view, and is formed on the upper wall of each head portion 4a and 4b. Corresponding to the sand discharge ports 9a, 9b of the sand hopper 3, there are provided circular openings 11a, 11b which also function as air inlets to be described later. Further, the blow head 4 can move in the horizontal direction from a sand supply position S1 to a sand blowing position S2 to be described later by operating a cylinder 13 (see FIG. 1) on a rail 12 provided at the upper part of the column 2. It is arranged.

  As shown in FIG. 1, the air supply means 5 includes two air tanks 15 arranged on the column 2 or outside the column 2, one end connected to the air tank 15, and the other end of each head of the blow head 4. It has two introduction pipes 16a and 16b connected to the openings 11a and 11b of the parts 4a and 4b. Extrusion cylinders 17a and 17b are arranged coaxially with the introduction pipes 16a and 16b above the column 2 of the introduction pipes 16a and 16b. The head portions 4a and 4b are pushed and moved downward by a predetermined amount against the urging force of the spring 14 (see FIG. 3).

  As shown in FIGS. 1 to 3, the upper die 6 has two recesses 6 a corresponding to the core shape formed on the lower surface thereof, and an extrusion pin corresponding to each recess 6 a on the upper surface side. An extrusion plate 18 having a vertical movement is disposed. The lower mold 7 is disposed on a lifting table 19, and has two concave portions 7a corresponding to the core shape formed on the upper surface thereof, and an extrusion pin 20 (FIG. 8) corresponding to the concave portion 7a. -M) are arranged so as to be movable up and down. Two core cavities are formed between the molds 6 and 7 by the recess 7 a of the lower mold 7 and the recess 6 a of the upper mold 6. In addition, as shown in FIG. 1, the movable discharge stand 21 for discharging | emitting the molded core is arrange | positioned at the side of the raising / lowering table 19 as needed.

  Next, an example of a specific molding method of the core using the core molding apparatus 1 configured as described above will be described based on the process diagram of FIG. Note that a cylinder head, which is a component of a motorcycle, will be described as an example of the core. The start preparation completion (K1) shown in FIG. 6 means that the blow head 4 stops at the sand supply position S1 and the sand S is supplied into the head portions 4a and 4b as shown in FIG. 7 is in the lowered position. When the elevating table 19 is raised in this state, the lower die 7 is raised (K2), and the state shown in FIG. 7A is obtained. In this state, the lower die 7 and the upper die 6 are clamped. The core cavity is formed between the molds 6 and 7.

  When the lower mold 7 and the upper mold 6 are clamped, the blow head 4 moves along the rail 12 to the blowing position S2 (K3), and the state shown in FIG. In this state, the blow head 4 is positioned. At this time, the pusher plate 18 is located at the right end in the figure of the rail 12. Next, one of the two extrusion cylinders 17a and 17b is actuated to lower one of the two head portions 4a and 4b of the blow head 4, and this head is lowered. The part 4a is pressure-bonded (K4) to the upper mold 6 to obtain the state shown in FIG. By this crimping, the opening 11a of the head portion 4a and the air tank 15 are in communication with each other via the introduction pipe 16a. At this time, the other head portion 4 b is not crimped to the upper mold 6.

  When one head portion 4a is pressure-bonded to one core cavity portion of the upper mold 6, air of a predetermined pressure is supplied from the air tank 15 through the introduction pipe 16a and the opening 11a as shown by an arrow a in FIG. It blows into the head part 4a (K5). By blowing this air, the sand S in the head portion 4a is filled into one core cavity, and when the air is blown into the head portion 4a, the other head portion 4a is separated from the upper mold 6. Therefore, even when air leaks from the upper surface of the upper mold 6, the air leak does not affect the other head portion 4b. When the blowing of air is completed for a predetermined time, the blown air is exhausted and firing of one core cavity is started (K6) as shown by the arrow b in FIG.

  When the exhaust of air is finished, the extrusion cylinder 17a is then operated to raise one head portion 4a to release the pressure bonding with the upper mold 6, and the extrusion cylinder 17b is operated to move the other head portion 4b Then, the other head portion 4b is pressure-bonded (K7) to the upper mold 6 to obtain the state shown in FIG. By pressure bonding to the upper mold 6 of the other head portion 4b, the opening 11b of the other head portion 4b and the air tank 15 are in communication with each other via the introduction pipe 16b. In this state, as shown in FIG. As described above, air is blown into the other head portion 4b as indicated by an arrow (K8). By blowing this air, the sand S in the head portion 4b is filled into the other core cavity, and the blown air is exhausted when the filling is completed, and then the core cavity is fired (K9). To do. The blowing of air into the other head portion 4b is also prevented from being adversely affected by air leakage because the one head portion 4a is separated from the upper mold 6.

  Then, the pressure bonding to the upper die 6 of the head portion 4b is released (K10) to obtain the state shown in FIG. 8G, and in this state, the blow head 4 is returned to the original position (position shown in FIG. 1) ( K11). When the blow head 4 returns to the initial position, as shown in FIG. 8 (h), both the core cavities are fired simultaneously (K12), and when this firing is completed for a predetermined time (K13), FIG. 8 (i) As shown in FIG. 8, the push-out plate 18 positioned on the upper mold 6 is lowered, and as shown in FIG. 8 (k), the elevation table 19 is lowered to lower the lower mold 7 (K14). .

  As a result, the core formed by the two core cavities is separated from the upper mold 6 and is positioned in the recess 7a of the lower mold 7, and this state is shown in FIG. 8 (l: lowercase letter L). As shown in FIG. 8 (m), the extrusion pin 20 is raised (K15) to be separated from the upper die 6 and the extrusion pin 20 is raised to lower the molded core to the lower die. 7 is released (K16), thereby completing the molding of the two cores.

  That is, according to this molding method, the blow head 4 is provided with two head portions 4a and 4b that can be operated completely independently, and the opening 11a as an air inlet corresponding to each head portion 4a and 4b. 11b and the introduction pipes 16a and 16b and the air tank 15, the sand S in each of the head portions 4a and 4b is placed in the two core cavities formed by the upper and lower molds 6 and 7, and air supply means The two cores can be molded almost simultaneously at the same time.

  Thus, in the core molding apparatus 1 of the above embodiment, the blow head 4 has the two head portions 4a and 4b, and the sand S in the sand hopper 3 is supplied to each of the heads. Since the air supply means 5 is provided corresponding to each of the portions 4a and 4b, air can be blown into the head portions 4a and 4b and exhausted independently, and into each core cavity. In addition to eliminating the shortage of sand S filling, it is possible to prevent interference between the head portions 4a and 4b and the core cavity due to air leakage, etc., and efficiently form two uniform cores in quality. be able to.

  In particular, since the blow head 4 is partitioned to reduce the volume of each head portion 4a, 4b, the dispersion of the air pressure during sand blowing can be reduced, and the lack of filling can be reliably eliminated, and the high air flow Use can be avoided and wear of the upper and lower molds 6 and 7 can be prevented. Also, the air supply means 5 is connected to openings 11a and 11b as air inlets provided in the head portions 4a and 4b of the blow head 4, and the openings 11a and 11b via the introduction pipes 16a and 16b. Since the air tank 15 is provided, air can be satisfactorily supplied independently into the head portions 4a and 4b through the openings 11a and 11b, etc., and into the core cavities of the sand S in the head portions 4a and 4b. Insufficient filling or the like can be reliably prevented.

  Further, since air is blown into the head portions 4a and 4b with a predetermined time difference so as not to be simultaneously with each other, air interference between the head portions 4a and 4b can be reliably prevented. At the same time, since firing is performed in response to air blowing and exhaust to each head portion 4a, 4b, the firing time of each core cavity corresponding to each head portion 4a, 4b can be arbitrarily set, and two The core can be formed more efficiently.

  Furthermore, since the sand hopper 3 has two hopper portions 3a and 3b partitioned corresponding to the respective head portions 4a and 4b, the sand hopper 3 has a larger distance from the sand discharge ports 9a and 9b than the one large hopper. Since the discharge can be performed smoothly, the molding operation of the two cores using the same sand S can be performed more efficiently, and different sand S can be accommodated in each of the hopper portions 3a and 3b, for example. The versatility of the core molding apparatus 1 can be improved, for example, cores of different forms can be molded simultaneously.

  In the above-described embodiment, the case where two cores are taken has been described. However, the present invention is not limited to this configuration, and can be applied to a plurality of places such as four pieces. Among these, the shape of the sand hopper 3 and the blow head 4 in the case of four picks is formed so as to have four hopper portions 3a to 3d and head portions 4a to 4d as shown in FIGS. 9 and 10, for example. Is done. In the above embodiment, the case where the core cavity is two cylinder heads having the same form has been described. However, in the present invention, the sand hopper 3 and the air supply means 5 are provided for each head portion 4a, 4b. Because they are provided independently, as described above, for example, when molding the core of the same shape with sand having different characteristics, or when molding the cylinder head with different shape with the same sand. It is also possible to use it.

  Furthermore, in the above embodiment, the two air tanks 15 are used for the air supply means 5, but for example, each head portion of the blow head 4 is switched while switching the air of one air tank 15 by an electromagnetic valve or a switching valve. It is also possible to adopt a configuration that blows into 4a and 4b. Further, in the above embodiment, the configuration of the entire apparatus, such as the arrangement of parts, the shape of the sand hopper 3 and the blow head 4 itself, and the like are merely examples. For example, a plan view shape is used as the sand hopper 3, etc. Modifications can be made as appropriate without departing from the spirit of the inventions.

  The present invention can be used not only for cores for automobile parts such as cylinder heads but also for cores for various parts of all other products.

The front view which shows one Embodiment of the core molding apparatus which concerns on this invention Rear view of the main part Same side view Top view of the sand hopper Top view of the blow head Process drawing showing an example of a core molding method using the molding apparatus Explanation of the same Other explanatory diagrams Plan view showing a modification of the sand hopper and blow head Plan view showing another modification of the sand hopper and blow head

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Core molding apparatus, 2 ... Column, 3 ... Sand hopper, 3a-3d ... Hopper part, 4 ... Blow head, 4a-4d ... Head part, ... -Air supply means, 6 ... upper mold, 6a ... recessed, 7 ... lower mold, 7a ... recessed, 9a, 9b ... sand discharge port, 11a, 11b ... opening (Air inlet), 12 ... rail, 17a, 17b ... extrusion cylinder, 18 ... extrusion plate, 19 ... lifting table, 20 ... extrusion pin, S ... sand, S1. ..Sand supply position, S2: Sand blowing position.

Claims (6)

  The sand in the sand hopper is supplied to each head section divided into a plurality of blow heads at the sand supply position, and the blow head is moved to the sand blowing position, and the air provided corresponding to each head section at that position. The air in the supply means blows and fills the sand in each head portion into a plurality of core cavities formed by upper and lower molds, and then fires to form a plurality of cores. The core molding method.   2. The core molding method according to claim 1, wherein the air is blown into each head portion with a predetermined time difference so that a plurality of head portions are not simultaneously formed.   The core molding method according to claim 1 or 2, wherein the firing is performed in response to air blowing and exhausting to each head portion.   A sand hopper for storing predetermined sand, a blow head in which sand in the sand hopper is divided into a plurality of sections at a sand supply position, and sand in each head part of the blow head are blown. Air supply means that blows and fills each of the core cavities formed by upper and lower molds provided corresponding to each head portion by the air at the insertion position. Molding equipment.   The core molding apparatus according to claim 4, wherein the sand hopper includes a plurality of hopper portions partitioned into a plurality corresponding to each head portion of the blow head.   The air supply means includes an air introduction port provided in each head portion of the blow head, and an air tank connected to each air introduction port via an introduction pipe. 5. A core molding apparatus according to 5.

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