Mold molding device

Abstract

To provide a mold molding device which enables relative motion of a molding flask and a pattern surface plate, and thereby can enhance mold strength on the side of the pattern surface plate.SOLUTION: There is provided a mold molding device in which opening parts for extracting core metal are formed on the side of facing wall mating faces of a molding flask so as to use a core using the core metal, wherein a pattern is arranged so that both ends of the pattern forming the shape of a baseboard supporting the core are arranged at a predetermined gap from an inner wall surface position of a lower raised frame corresponding to a position formed with the opening parts of the molding flask, and a blocking member for blocking the openings when the mold is molded is mounted in the upper part of the lower raised frame.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an apparatus for molding a mold using molding sand. [Background technology]

[0002] The mold-making apparatus shown in Patent Document 1 includes a molding sand filling device that fills a molding flask with molding sand, and a mold-making apparatus that compresses the molding sand in the flask. The molding sand filling device shown in Patent Document 1 is equipped with a squeeze table and a squeeze foot. Molding sand is poured into a molding space formed by a stacked flask in which a lower flask, a molding flask, and an upper flask are stacked, and a pattern platen on which a pattern is attached, and is pressed between the squeeze table and the squeeze foot to form a mold. During molding, both a rear squeeze performed from the rear side of the model and a model surface squeeze performed from the model surface side are performed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3577450 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the past, a core steel CO was used in molding using a long core CR (see Fig. 14). The flask MF used to mold the mold CM has an opening OP for removing the core steel CO after pouring (see Fig. 14). The opening OP is formed on the mating surface side of the wall of the flasks MF that extend parallel to each other and face each other. During molding, as shown in Figures 15 and 16, the inner edge IE of the opening OP of the molding flask MF for extracting the core sand CO is brought into close contact with the outer periphery of the model PT (baseboard SB), which is formed to the same shape as the outer periphery of the baseboard SB, to prevent the molding sand CS from leaking out. This means that it is not possible to squeeze from the pattern surface side, which requires relative movement between the flask MF and the pattern platen PSP, and this poses the problem of reduced mold strength on the pattern platen PSP side. The portion supporting the core CR is called the baseboard SB, but generally, the portions of the model PT that form the portions corresponding to the baseboard SB of the core CR at both ends are also called baseboards SB. This specification follows this rule.

[0005] The present invention has been made in consideration of the above-mentioned problems in the conventional molding apparatus, and its object is to provide a molding apparatus which can improve the strength of the mold on the pattern plate side by enabling relative movement between a molding flask, which has an opening formed on the mating surface between the opposing walls for removing a core steel, and a pattern plate during molding. [Means for solving the problem]

[0006] According to a first aspect of the present invention, in order to use a core that uses a core steel, the mold making apparatus has openings formed on the mating surfaces of the opposing walls of the molding flask for removing the core steel, both ends of the pattern, which is formed in the same shape as a baseboard supporting a core, are disposed with a predetermined gap from the inner wall surface of the underfill flask which corresponds to the position where the open portion of the flask is formed; A blocking member for blocking the open portion when molding a mold is attached directly or indirectly to the upper portion of the underlayment frame. Mold molding equipment.

[0007] According to this, by attaching a blocking member to the upper part of the underfill frame, the position that will become the baseboard end face of the model can be positioned slightly inward from the inner surface of the underfill frame, and the model plate can enter inside the underfill frame. This allows relative movement between the molding flask and the model, making it possible to squeeze from the model surface side, and increasing the mold strength on the model plate side.

[0008] According to the mold making apparatus of the second aspect of the present invention, in the mold making apparatus of the first aspect, a draft is provided on the inner wall surface side of the covering member.

[0009] This makes it possible to prevent chipping of corners that occurs when demolding if the inner wall surface of the covering member is a vertical surface when molding a general product without a core.

[0010] According to the third aspect of the present invention, in the mold making apparatus of the first aspect, the open portion of the molding flask is formed to be larger than the outer diameter of the baseboard. This increases the working space for removing the core and the core sand, improving workability.

[0011] According to a fourth aspect of the mold making apparatus of the present invention, in the first aspect of the mold making apparatus, the predetermined gap between the end face of the baseboard and the position of the inner wall surface of the underlayment frame is set to 0.5 to 1 mm. This makes it possible to prevent the outflow of molding sand and to smoothly squeeze the surface side of the model. [Brief description of the drawings]

[0012] [Figure 1] 1 is a schematic front view showing an embodiment of a mold making apparatus of the present invention. FIG. [Diagram 2] FIG. 2 is a side view showing the flask, the pattern plate, and the closing member. [Diagram 3] FIG. 2 is a plan view showing the model, the covering member, and the backing plate, partially in cross section, as viewed from above. [Figure 4] 11 is a schematic diagram showing a mounting structure of the closing member to the backing plate. FIG. [Diagram 5] FIG. 13 shows the state in which the pattern and the pattern plate have been raised and inserted into the flask side. [Figure 6] FIG. 13 is a view before the model and the model surface plate are raised. [Figure 7] FIG. 2 is a diagram showing a process before casting sand is poured into the overlapping frame. [Figure 8] FIG. 2 is a diagram showing the process of pouring molding sand into a stacking frame. [Figure 9] FIG. 13 is a diagram showing a process in which the molding sand supplying device is replaced with a squeeze foot. [Figure 10]FIG. 13 is a diagram showing a preliminary squeeze process from the rear side. [Figure 11] FIG. 13 is a diagram showing the process of squeezing from the model surface side. [Figure 12] FIG. 13 is a diagram showing the main squeezing process from the rear side. [Figure 13] FIG. [Figure 14] FIG. 13 is a diagram showing the state in which molten metal is poured using a core and a core in a conventional example. [Figure 15] FIG. 13 is a diagram showing a state in which molding sand has been charged in a conventional example. [Figure 16] FIG. 13 is a diagram showing a state in which squeezing is performed from the rear side in a conventional example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] (Embodiment) An embodiment of a mold making apparatus 1 according to the present invention will be described below with reference to FIGS.

[0014] 1, a mold molding apparatus 1 in the embodiment includes a squeeze table (not shown), a molding sand supplying device 3, a squeeze foot 4 (see FIG. 9), a carrier plate 5, a lower filling frame 6, an upper filling frame 8, a molding flask MF, a model PT, and a model surface plate PSP. The molding sand supplying device 3 and the squeeze foot 4 are connected to a shuttle device (not shown), and reciprocate horizontally between a molding position where molding is performed and a standby position away from the molding position.

[0015] Of these devices and parts, the squeeze table, the casting sand supply device 3, the squeeze foot 4, the carrier plate 5, the top filling frame 8, and the model surface plate PSP have little relevance to the present invention and are well-known technologies, so their explanation will be omitted. These techniques are disclosed, for example, in Japanese Patent No. 3577450.

[0016] The main components that differ from the description in the exemplified publication and that address the problem that the invention is intended to solve will be described below.

[0017] (Lowering frame) The lower filling frame 6 is provided below the flask MF so that the lower filling frame 6 can be stacked to execute the pattern surface squeeze, and a lower squeeze allowance is secured.

[0018] The lowering frame 6 is made of, for example, iron, formed into a rectangular frame, and is provided so as to surround the outer periphery of the model surface plate PSP and the carrier plate 5. The lowering frame 6 is capable of moving vertically relative to the model surface plate PSP and the carrier plate 5. The mechanism by which the lowering frame 6 is held and moves relative to these components is well known technology, so a description thereof will be omitted.

[0019] A backing plate 6a is provided on the upper inside of the lower filling frame 6. The backing plate 6a is a member that mainly comes into contact with the lower end of the flask MF when the flasks MF are stacked on the lower flask 6. The backing plate 6a is made of iron, for example, and is formed in a rectangular shape along the upper part of the lower flask 6. A closing member 7 is provided on the upper surface of the backing plate 6a at a position facing the open portion OP of the flask MF. The inner wall surface position 6wp, which is the inner surface of the lower filling frame 6, becomes the reference position for a predetermined gap t formed between the end surface of the model PT described later.

[0020] (Blocking material) When flasks MF are stacked on the lower flask 6 to form a stacked flask SKF (see FIG. 7), the closing member 7 closes the open space of the open portion OP of the flask MF to prevent leakage of the molding sand CS filled in the stacked flask SKF. The closing member 7 is made of iron, for example, and is formed in a semicircular shape that follows the shape of the open portion OP of the flask MF. Note that the closing member 7 is not limited to a semicircular shape as long as it has a shape that closes the opening of the open portion OP.

[0021] During molding, both ends of the model PT (baseboard SB), which has the same shape as the baseboard SB supporting the core CR, are positioned with a predetermined gap t from the inner wall surface position 6wp of the lower flask 6 corresponding to the position where the opening OP of the flask MF is formed. The predetermined gap t is set to, for example, 0.5 to 1 mm.

[0022] The inner wall surface 7w of the closing member 7 is provided at a position equivalent to the inner wall surface position 6wp of the lower bank frame 6, and has a predetermined gap t between it and the end face of the baseboard SB. As shown in Figures 5 and 6, the closing member 7 is integral with the lower bank frame 6 and can move vertically relative to the model surface plate PSP. Further, the inner wall surface 7w of the blocking member 7 is provided with a draft gradient that slopes outwardly toward the upper side.

[0023] As shown in Figures 3 and 4, the blocking member 7 is fixed to the backing plate 6a by, for example, fastening bolts B into three through holes 6ah that penetrate the backing plate 6a from top to bottom and three female threaded holes 7h that are formed upward from the lower end of the blocking member 7.

[0024] (Flask) The flask MF is formed by squeezing the molding sand CS filled in a superimposed flask SKF, which is made up of a lower flask 6, a lower flask MF, and a lower flask 8 stacked in that order, into a mold CM inside the flask MF. The flask MF is made of iron, for example, and is formed into a rectangular frame. After the mold CM is molded inside the flask MF, the mold for the upper flask and the mold for the lower flask are mated at their mating surfaces to form the mold CM into which molten metal can be poured.

[0025] In this embodiment, the mold CM formed in the molding flask MF is into which a long core CR is inserted and molten metal is poured. The long core CR has a rod-shaped core bar CO for reinforcement (see FIG. 14). For this reason, the flask MF has openings OP in the shape of semicircular arcs on the mating surfaces of the opposing short sides for removing the core wire CO (see Figure 2). The opening OP can be formed larger than the outer diameter of the baseboard SB as long as it can be blocked by the blocking member 7. By making the opening OP larger, the work of removing the core wire CO can be made easier.

[0026] The core steel CO is extracted during the cooling process after pouring. The reason for extracting the core steel CO during the cooling process, in other words before the dismantling process, is that the position of the core steel CO is not fixed after the dismantling process, making it difficult to recover the core steel CO.

[0027] (model) The dimension between the longitudinal ends (baseboard SB) of the model PT, which has the same shape as the baseboard SB that supports the core CR, is set so that a predetermined gap t is created from the inner wall surface position 6wp of the underfill frame 6 corresponding to the position where the open portion OP of the molding flask MF is formed. This allows the end of the model PT (baseboard SB) to be prevented from interfering with the edge of the open portion OP of the flask MF (inner edge IE), and allows the model plate PSP to be inserted into the flask SKF. In other words, the model PT and flask MF can move relative to each other, allowing squeezing from the model surface side.

[0028] (Control device) The control device (not shown) controls the operation of, for example, a hydraulic or electric drive mechanism that drives the squeeze foot 4. The control device similarly controls the lifting and lowering operation of the squeeze table. The control device also controls the drive of the shuttle device. Furthermore, the control device also controls the drive of the molding sand supply device 3, etc.

[0029] (Activation) The operation of the mold making apparatus 1 configured as above will be described below with reference to FIGS. A squeeze table (not shown) is disposed at a position where the mold CM is formed. On the squeeze table, as shown in Fig. 7, a carrier plate 5 to which a model surface plate PSP is attached is disposed.

[0030] A bottom flask 6 is arranged to surround the model surface plate PSP. A molding flask MF and a top flask 8 are stacked on the bottom flask 6 in order to form a stacked flask SKF. A molding sand supplying device 3 in which molding sand CS is stored is positioned above the overlapping frame SKF.

[0031] Next, as shown in FIG. 8, the control device drives the shutter of the molding sand supplying device 3 to feed the stored molding sand CS into the overlapping flask SKF. At this time, the opening of the open portion OP of the flask MF is closed by the closing member 7, so that the molding sand CS is prevented from leaking out from the open portion OP.

[0032] Next, the control device drives the shuttle device to position the squeeze foot 4 at the position where the mold CM is to be formed, as shown in Fig. 9. The upper surface of the molding sand CS is made flat by a device for removing excess sand provided at the lower end of the molding sand supplying device 3. Then, the control device moves the lower end of the squeeze foot 4 close to the upper surface of the casting sand CS.

[0033] Next, the control device drives the squeeze foot 4 to perform a preliminary squeeze from the rear side of the model PT, as shown in FIG. In this preliminary squeeze, the squeeze foot 4 is inserted into the superimposed frame SKF from above, which is the rear surface of the model PT. The preliminary squeeze is performed with a relatively small pressing force.

[0034] Next, as shown in Fig. 11, the control device raises the squeeze table (not shown) to raise the model surface plate PSP attached to the carrier plate 5. At this time, the upper end of the upper filling frame 8 is restricted from rising by a stopper (not shown). Therefore, the pattern platen PSP enters the overlapping frame SKF from below, and the pattern surface side squeeze is performed. The pattern surface side squeeze compacts the mold CM near the pattern platen PSP, improving the strength of the mold CM on the pattern platen PSP side.

[0035] Next, the control device drives the squeeze foot 4 to perform the main squeeze from the rear side, as shown in FIG. In this way, by squeezing the model PT from both the rear side and the front side, a mold CM with uniform strength is created, making it possible to cast an exquisite casting product.

[0036] Next, the control device lowers the squeeze table and disassembles the overlapping flask SKF into the lower flask 6, the flask MF, and the upper flask 8. Then, the mold CM formed in the flask MF is transported to the next process (not shown).

[0037] In the next process, a core CR (containing steel CO) is set inside the mold CM, and the upper mold is placed on top of the lower mold, and then they are transported to the pouring process (not shown). The mold CM poured in during the pouring process is cooled in the cooling process. During the cooling process, the core CO is extracted (not shown). Once it has cooled sufficiently, the frame is removed and the casting is removed (not shown). The same process is repeated below.

[0038] As is clear from the above description, the mold making apparatus 1 of this embodiment uses an upper filling frame 8 stacked above the flask MF to squeeze the pattern surface side, and uses a lower filling frame 6 stacked below the flask MF to squeeze the back side of the model PT. In addition, since a core CR that uses a core steel CO is used, the mold making apparatus 1 has openings OP formed on the mating surfaces of the opposing walls of the flask MF for removing the core steel CO.

[0039] The ends of the model PT (baseboard SB), which is formed to have the same shape as the baseboard SB that supports the core CR, are positioned with a specified gap t from the inner wall surface position 6wp of the lower filling frame 6 which corresponds to the position where the open portion OP of the molding flask MF is formed, and a blocking member 7 for blocking the open portion OP when molding the mold CM is indirectly attached to the upper part of the lower filling frame 6 via a backing plate 6a.This is a mold molding device 1.

[0040] According to this, by attaching the blocking member 7 to the upper part of the lower filling frame 6, the position which will become the end face of the baseboard SB of the model PT can be positioned slightly inward from the inner surface of the lower filling frame 6, and the model platen PSP can enter inside the lower filling frame 6. This enables relative movement between the molding flask MF and the model PT, making it possible to squeeze from the model surface side, and increasing the mold strength on the model platen PSP side.

[0041] In the mold making apparatus 1 of this embodiment, a draft angle is provided on the inner wall surface 7w side of the covering member 7.

[0042] This makes it possible to prevent chipping of corners that occurs during demolding when molding a general product without a core and the inner wall surface 7w side of the covering member 7 is a vertical surface.

[0043] In the mold making apparatus 1 of this embodiment, the opening OP of the molding flask MF is formed to be larger than the outer diameter of the baseboard SB. This increases the working space for removing the core CO and the core CR, improving workability.

[0044] In the mold making apparatus 1 of this embodiment, the predetermined gap t between the end face of the baseboard SB and the inner wall surface position 6wp of the underlayment frame 6 is set to 0.5 to 1 mm. This makes it possible to effectively prevent the outflow of the casting sand CS and to smoothly squeeze the surface side of the model. Although the present invention is described as performing both squeezing from the back side and squeezing from the model surface side, the present invention is not limited to this. For example, the present invention can be used in a mold molding apparatus that performs squeezing only from the model surface side. In addition, the predetermined gap t is set to 0.5 to 1 mm, but is not limited to this. For example, it can be set to a large gap of 2 mm or more. By making the gap larger, the dimensional accuracy of the baseboard can be reduced, and models, etc. can be easily and inexpensively produced.

[0045] The present invention is not limited to the above-described embodiment and shown in the drawings, and can be modified and carried out as appropriate without departing from the spirit and scope of the present invention. [Explanation of symbols]

[0046] 1: mold making device, 6: underfill frame, 6a: backing plate, 6wp: inner wall surface position, 7: closing member, 7w: inner wall surface, CM: mold, CO: core steel, CR: core, CS: casting sand, MF: flask, OP: open section, PSP: model surface plate, PT: model.

Claims

1. A mold making apparatus in which openings for removing a core steel are formed on the mating surfaces of opposing walls of a molding flask in order to use a core steel-containing core, the pattern to be placed on the flask is formed in the same shape as a baseboard supporting the core, and both ends of the pattern are placed with a predetermined gap from the inner wall surface of the underfill flask corresponding to the position where the open portion of the flask is formed; A mold making apparatus in which a closing member for closing the open portion when making a mold is attached directly or indirectly to the upper part of the lower filling frame.

2. 2. The mold making apparatus according to claim 1, wherein a draft is provided on an inner wall surface of the covering member.

3. 2. The mold making apparatus according to claim 1, wherein the open portion of the molding flask is formed to be larger than the outer diameter of the baseboard.

4. 2. The mold making apparatus according to claim 1, wherein the predetermined gap between the end face of the baseboard and the position of the inner wall surface of the underlayment frame is set to 0.5 to 1 mm.

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