JPH0655240A - Lost foam pattern casting method and casting device and shifting method thereof and separation method from molding flask - Google Patents

Abstract

PURPOSE:To separate a molding from a molding flask without turning over the molding flask of a lost foam pattern casting device. CONSTITUTION:A hollow part 12 is arranged in the inner part of a side wall 11 in the molding flask 10, and an opening part 12 is opened in the inner surface of the side wall 11 and covered with a gauze 15. Vinyl sheets 16, 18 are arranged on the upper and the lower surfaces of a molding sand 17, and by sucking the hollow part 12, gas in the molding sand 17 is sucked. By this method, the molding flask 10, molding sand 17, lost foam pattern groups 20A-20D and the vinyl sheets are integrated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved disappearance model casting apparatus, and an improved casting apparatus moving method and unraveling method.

[0002]

2. Description of the Related Art As is well known, the vanishing model casting method is one in which a vanishing model made of foamed plastic or the like is buried in foundry sand contained in a casting frame, and molten metal is poured into the vanishing model. Is a method of burning, vaporizing and replacing with molten metal, and then cooling and solidifying this molten metal to form a casting.

Generally, a casting frame used for vanishing model casting has a bottomed box shape with an open top. When casting using this casting frame, in order to remove the casting from the casting sand after casting, reverse the casting frame and reverse the top and bottom, and take out from the casting frame together with the casting sand, or vibrate the casting frame and cast the casting. The method is to lift the casting while shaking off the sand.

[0004]

However, when the casting frame is inverted to take out the casting, a large-scale device for inverting the casting frame is required, and a wide space is required for safe work. It was a disadvantage. In particular, this problem became remarkable as the size of the flask increased. On the other hand, the method of hoisting the casting while vibrating the casting frame is not efficient because it takes a little time, and has the drawback that the casting sand is blown up to deteriorate the working environment.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object thereof is to provide a vanishing model casting apparatus capable of taking out a casting without inverting the casting frame. Where it is.

[0006]

The present invention has been made in order to achieve the above-mentioned object, and its gist resides in the following disappearance model casting method, disappearance model casting apparatus, its moving method and unraveling method. (1) In a vanishing model casting device in which a vanishing model is embedded in foundry sand contained in a casting frame, a vertically open casting frame surrounded by a side wall and having a sand storage portion inside, A suction mechanism which is provided on the side wall of the casting frame and which sucks gas in the sand storage portion, is arranged above and below the casting frame in which the sand storage portion is filled with the molding sand, and the gas in the sand storage portion is sucked by the suction mechanism. A vanishing model casting apparatus, comprising: an airtight sheet that is brought into close contact with the molding sand by suction. (2) By sucking the gas in the sand container by the above suction mechanism, the airtight sheets arranged above and below the casting frame are brought into close contact with the molding sand filled in the sand container, and the molding sand and this molding sand are preliminarily attached. The vanishing model casting apparatus according to (1) above, wherein the vanishing model that has been buried cannot be removed from the casting frame, and the casting frame, the molding sand, and the vanishing model can be moved so as to be separated and integrated. How to move. (3) By sucking the gas in the sand storage portion by the suction mechanism of the disappearance model casting device, the airtight sheets arranged above and below the casting frame are brought into close contact with the molding sand filled in the sand storage portion to form the casting sand. A method for casting vanishing model, comprising sand-consolidating, then pouring the molten metal to replace the vanishing model previously buried in the casting sand with molten metal, and cooling and solidifying to form a casting. (4) By sucking the gas in the sand container by the suction mechanism, the airtight sheets arranged above and below the casting frame are brought into close contact with the molding sand filled in the sand container, and the molding sand and this molding sand It is characterized in that the casting formed by replacing the vanishing model that has been buried in advance with the molten metal cannot be separated from the casting frame, and the casting frame, the molding sand, and the casting can be separated and integrally moved. The method for moving the vanishing model casting apparatus according to (1) above. (5) Prepare a net-shaped casting receiver, arrange the above-mentioned vanishing model casting device in which the casting is buried in the casting sand on the casting receiver, and remove the airtight sheet attached to the lower part of the casting frame. The unraveling frame of the vanishing model casting apparatus according to (1), characterized in that the foundry sand contained in the sand container is relaxed and dropped into the foundry receiver, and the foundry is received by the foundry receiver. Method.

[0007]

The upper and lower sides of the casting frame are opened, and the molding sand and the casting can be dropped and taken out from the casting frame by removing the airtight sheet arranged under the casting sand. Although the upper and lower sides of the flask are open, when airtight sheets are placed above and below and the gas in the sand storage section is sucked by the suction mechanism, both airtight sheets adhere to the molding sand and compact the molding sand, A frame,
The foundry sand and the vanishing model or the foundry embedded in the foundry sand are separated and integrated. Therefore, the vanishing model casting apparatus can be moved by lifting it in this state. Further, when the suction by the suction mechanism is stopped and the lower airtight sheet is removed, the foundry sand and the foundry fall off the casting frame.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings of FIGS. FIG. 1 is a vertical sectional view of a vanishing model casting apparatus according to the present invention, and FIG. 2 is a plan view of the same.

The casting frame 10 of this vanishing model casting apparatus is composed of an annular side wall 11 whose upper and lower sides are opened. The inside of the side wall 11 is a cavity 12, and the inside surrounded by the side wall 11 is a sand container 13. The side wall 11 has a large opening 14 connected to the sand storage portion 13, and the opening 1
4 is covered with a fine mesh 15 which does not allow the molding sand 17 to pass through. The cavity 12 is connected to a vacuum pump (not shown), and the air in the cavity 12 is sucked by the vacuum pump so that the gas in the sand container 13 can be sucked. In this example,
The cavity 12, the opening 14, the wire net 15 and the vacuum pump constitute a suction mechanism.

A vinyl sheet is provided below the casting frame 10.
An (airtight sheet) 16 is arranged, a sand storage portion 13 on the vinyl sheet 16 is filled with molding sand 17, and a vinyl sheet (airtight sheet) 18 is further arranged on the molding sand 17. In the foundry sand 17, four vanishing model groups 20A, 20B, 20C, 20 having different casting methods are used.
D is buried. As shown in FIG. 2, the disappearance model groups 20A to 20D are spaced apart from each other and dispersed in the horizontal direction.

The disappearance model group 20A will be described. The water pool 21 of the disappearance model group 20A is the vinyl sheet 18 described above.
A sprue bar 22 that is installed above and extends downwardly from a bath 21 penetrates the vinyl sheet 18. A runner 23 extends horizontally from the tip of the sprue bar 22, a plurality of weirs 24 extend downward from the runner 23, and a product part 25 is connected to the lower ends of the weirs 24. The product part 25 is a part that replaces the molten metal and finally becomes an independent casting product.
The sprue bar 22, the runner 23, the cough 24 and the product portion 25 are made of foamed plastic. The other disappearance model groups 20B to 20D also have the same configuration, although the shape and size of each part are different from those of the disappearance model group 20A.

Next, the disappearance model group 20A to the molding flask 10
The setting procedure of 20D will be described with reference to FIGS. 3 and 5 are schematic configuration diagrams of a casting sand filling device. In FIG. 3, reference numeral 30 is a movable table provided so as to be movable on the floor F. A lifter 31 is installed on the moving table 30. The lifter 31 has an air bag 32 on its upper part.
Supports a vibrating table 33 installed thereon. Then, air is injected into the airbag 32 to inflate it to raise the vibrating table 33 (see FIG. 5), and air in the airbag 32 is exhausted to wither and lower the vibrating table 33 (see FIG. 3). ).

The vibrating table 33 is adapted to be vibrated by a motor 34, and conditions such as vibration direction (horizontal vibration and vertical vibration), frequency and amplitude can be appropriately set. .

A vibration absorbing device 35 is mounted on the vibrating table 33. FIG. 4 is an external perspective view of the vibration absorbing device 35. The vibration absorbing device 35 includes a box body 36 having a hollow inside, and the box body 36.
The vibration absorbing plates 38 and 39 made of rubber are attached to the peripheral edge of the top plate 37 and the peripheral edge of the bottom plate. Top plate 37
A large number of holes 40 are opened in the hole and communicate with the internal cavity.
Further, the cavity inside the box body 36 is connected to a vacuum pump and a compressor (not shown) so that air can be sucked and discharged.

The vinyl sheet 16 is laid on the vibration absorbing device 35. This vinyl sheet 16 sucks the inside of the box body 36 with a vacuum pump, and
It is closely attached to the top plate 37 of No. 5. Then, the casting frame 10 is placed on the vinyl sheet 16. At this stage, the molding sand 17 and the disappearance model groups 20A to 20D are not contained in the flask 10.

The moving table 30 is moved to position the flask 10 under the sand hopper 41 (see FIG. 5).
The sand hopper 41 is installed so as to be able to move up and down, and is raised when the moving table 30 moves. Sand hopper 41
Has a gate at the bottom thereof, and by opening and closing the gate, the casting sand contained in the hopper 41 can be started and stopped. A rubber sealing material 42 is attached to the periphery of the bottom surface of the hopper 41.

Next, the hopper 41 is lowered so that the sealing material 42 is located above the casting frame 10 with a slight distance therebetween. After that, the casting frame 10 is raised by inflating the airbag 32 of the lifter 31, and the upper surface of the side wall 11 is abutted against the sealing material 42. And sand hopper 4
The gate 1 is opened to drop foundry sand into the flask 10, and floor sand is laid in the sand container 13 of the flask 10. After that, the gate is closed and the vibrating table 33 is vibrated under a predetermined vibration condition to solidify the floor sand. The vibration is stopped after the floor sand is completely solidified.

Next, the airbag 32 is deflated and the casting frame 10 is
Away from the sealing material 42, and further, the sand hopper 4
1 is raised to create a working space above the flask 10. Then, the disappeared model groups 20A to 20D are dispersedly arranged on the floor sand as shown in FIG. At this time, the basin 21 is not attached. Further, this opening is closed by an appropriate simple means so that the molding sand does not enter from the upper opening of the gate rod 22.

After the set of the disappearing model groups 20A to 20D is completed, the sand hopper 41 is lowered again, and the airbag 3
2 is inflated and the casting frame 10 is abutted against the sealing material 42. Then, the gate of the sand hopper 41 is opened to drop the foundry sand into the flask 10, and the vane bars 22 are exposed to bury the disappeared model groups 20A to 20D in the foundry sand. After that, the gate is closed, and the vibrating table 33 is vibrated under a predetermined vibration condition to solidify the foundry sand. After completing the sand compaction of the foundry sand, the vibration is stopped.

Next, the gate of the sand container hopper 41 is opened to drop the foundry sand into the flask 10, and the respective sprue rods 22 are buried in the foundry sand except for their upper ends. After that, the gate is closed, the vibrating table 33 is vibrated under a predetermined vibration condition, and the foundry sand 17 accommodated in the sand accommodating portion 13 is solidified. After the completion of sand compaction, the vibration is stopped, the airbag is deflated, the sand hopper 41 is raised, and a working space is created in the upper portion of the casting flask 10.

Next, the upper opening of each sprue bar 22 is opened, and the vinyl sheet 1 is placed on the casting frame 10 and the molding sand 17.
Place 8 In addition, each sprue bar 2 is attached to the vinyl sheet 18 in advance.
Make a hole so that 2 can be inserted. Then, a basin 21 is provided at the upper end of each sprue bar 22.

Next, the gas in the sand container 13 is sucked by sucking the cavity 12 of the casting flask 10 with a vacuum pump. Then, the vinyl sheets 16 and 18 arranged on the upper and lower sides of the casting frame 10 are attached to the upper and lower surfaces of the side wall 11 of the casting frame 10 and the molding sand 1
7, the molding sand 17 is strongly compacted, and as a result, the casting frame 10, the molding sand 17, the vinyl sheets 16 and 18, and the disappeared model groups 20A to 20D are integrated.
At this time, the suction in the box body 36 of the vibration absorbing device 35 is stopped, and air is sent into the box body 36, so that the vinyl sheet 16 is easily separated from the vibration absorbing device 35.

While continuing to suck the cavity 12 of the casting flask 10, the casting flask 10, the molding sand 17, the vinyl sheets 16 and 18, and the disappeared model groups 20A to 20D are integrated, and the casting flask 10 is operated by means of a crane or the like. It is moved in the air and placed on the surface plate 50. This is the state shown in FIG.

By the way, as described above, the vibration for solidifying the foundry sand 17 is divided into three times, but in any case, the vibration absorbing device 3 is provided between the casting frame 10 and the vibrating table 33.
5 is installed and the upper surface of the side wall 11 of the flask 10 is abutted against the sealing material 42 of the sand hopper 41, so that the vibration of the vibrating table 33 is appropriately absorbed, The molding flask 10 and the molding sand 17 are prevented from dancing.

Next, a casting method using the above disappearance model casting apparatus will be described. While sucking the cavity 12 of the casting frame 10 by the vacuum pump and sucking the gas of the molding sand 17,
The molten metal is sequentially poured into the pool 21 of the disappearance model groups 20A to 20D. More specifically, first, the molten metal is poured into the pool 21 of the disappearance model group 20A. Then, the molten metal flows through the sprue rod 22, the runner 23, the coughs 24, and the product parts 25 while replacing the foamed plastic by burning or vaporizing the foamed plastic.

By the way, when hot metal is poured into the disappearing model group 20A, the high-temperature gas generated by the combustion or vaporization of the foamed plastic is the molding sand 17 around the disappearing model group 20A.
However, these gases are sucked into the cavity 12 of the flask 10 located in the vicinity thereof. At the same time, the heat of the molten metal is discharged together with the gas. Therefore, heat when pouring into the disappearance model group 20A is not transmitted to the other disappearance model groups 20B to 20D, and the foamed plastics constituting them are softened and vaporized to be deformed or hollow. Absent.

When the pouring into the disappearance model group 20A is completed,
It pours in the disappearance model group 20B. Even when pouring into the disappearance model group 20B, heat at the time of pouring is discharged to the outside through the cavity 12, so that the disappearance model groups 20C and 20D in the state before pouring are deformed at this point. It does not become hollow or hollow. Similarly, the disappearance model groups 20C, 20
Pour the water from the dedicated water pool 21 into D.

As described above, the disappearance model groups 20B to 20D are kept in the original shape until the molten metal is poured from each of the pools 21, and the molten metal is poured from the dedicated pool 21 to correspond to each of them. The disappearance model groups 20B to 20D are burned and vaporized to replace the molten metal. as a result,
Each disappearing model group 20B to 2 according to the desired shape and size
It is possible to cast a casting product corresponding to the 0D product portion 25. According to this disappearance model casting apparatus, one casting frame 1
It is possible to set four vanishing model groups 20A to 20D in 0 and cast each.

In this embodiment, since four vanishing model groups 20A to 20D are set in the flask 10, the heat of pouring into one vanishing model group causes the other vanishing model groups to lose their shape. In order to prevent this from happening, the gas in the casting sand 17 is sucked during pouring as well. However, when a single vanishing model or vanishing model group is set in the flask 10 for casting, pouring is performed. It is not necessary to suck the molding sand 17 at that time.

Next, a method of taking out this casting from the casting frame 10 after cooling and solidifying the molten metal, that is, a demolding method will be described. FIG. 6 is a schematic configuration diagram of the unraveling device. In the figure,
Reference numeral 60 is a recovery hopper, and the recovery hopper 60 is supported by a stand 61. The entrance opening of the recovery hopper 60 can be opened and closed by a lid 62. A casting receiving box (casting tray) 63 is installed above the recovery hopper 60. The casting receiving box 63 is attached on a roller 64 rotatably attached to the upper part of the pedestal 61,
It can be pulled out in the direction orthogonal to the paper surface. The bottom plate 65 of the casting receiving box 63 has a net-like shape, and the casting sand 17
Can pass through.

A flask support device 66 is provided near the pedestal 61.
Is provided. The casting flask 10 can be attached to and detached from the casting flask supporting device 66, and the casting flask 10 is supported above the casting receiving box 63 so as to be able to move up and down. A dust collecting hood 67 is installed above the flask 10 supported by the flask supporting device 66 so as to be vertically movable and horizontally movable.

First, the dust collecting hood 67 of the unraveling device is moved to leave the casting receiving box 63 above and the cover 62 of the recovery hopper 60 is removed. After the molten metal is cooled and solidified in the disappearance model casting apparatus in the state of FIG.
While continuing to suck the hollow 12 of the casting frame 10, the casting sand 17, the molding sand 17, the vinyl sheets 16 and 18 and the castings (20A to 20D), and moving the casting frame 10 in the air by means of a crane or the like, It is attached to the frame support device 66. And
The casting flask 10 is lowered and placed on the casting receiving box 63, and the dust collecting hood 67 is arranged above the casting flask 10 with a predetermined distance.

Next, the flask 10 is supported by the flask support device 66.
Is slightly raised, and a gap is provided between the flask 10 and the casting receiving box 63, and a gap is provided between the flask 10 and the dust collecting hood 67. Then, at the same time as stopping the suction of the cavity 12 of the casting flask 10, the vinyl sheets 16 and 18 attached above and below the casting flask 10 are pulled and removed by an appropriate means, and then the casting flask 10 is quickly lowered. Then, the dust collecting hood 6 is placed on the casting receiving box 63.
7 is put on the flask 10.

When the suction of the cavity 12 is stopped and the lower vinyl sheet 16 is removed, the casting sand 17 loses its support and relaxes, and drops together with the castings (20A to 20D) into the casting receiving box 63. Then, the castings (20A to 20D) are caught and left on the bottom plate 65 of the casting receiving box 63, and the casting sand 1
7 passes through the bottom plate 65 and falls into the recovery hopper 60.
When all of the casting and the casting sand 17 have fallen into the recovery hopper 60, the lid 62 is closed. At the time of this unraveling, the sand dust rising above the casting flask 10 is sucked into the dust collecting hood 67 and collected by a dust collector (not shown). Also, the recovery hopper 6
The dust dust rising in 0 is the dust collection pipe 6 of the collection hopper 60.
It is conveyed to a dust collector (not shown) via 8 and collected.

A sheet 70 is provided below the dust collecting hood 67.
Is attached and hangs around the top of the flask 10. A sheet 71 is also attached to the lower portion of the casting frame 10 and hangs around the upper portion of the casting receiving box 63. These sheets 70 and 71 are provided between the flask 10 and the dust collecting hood 63, or between the flask 10 and the casting container 6
It prevents the dust from leaking from between 3.

The foundry sand contained in the recovery hopper 60 is
It is carried out from the lower outlet 69 by an appropriate means, subjected to a predetermined treatment, and then recycled to the sand container hopper 41 for reuse.

Next, after raising the dust collecting hood 67, the flask 10 is raised by the flask supporting device 66 to separate the flask 10 from the casting receiving box 63. Then, the casting receiving box 63 is pulled out, and the castings (20A to 20D) are taken out. As described above, in the case of this disappearance model casting apparatus, the casting frame 10
The solution frame can be set without reversing. In addition, if the above is done, dust will not fly to the work place during the unraveling, and a good work environment can be maintained.

[0038]

As described above, according to the present invention, the excellent effect that the frame of the vanishing model casting apparatus can be unframed without being inverted is exhibited.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a vanishing model casting apparatus according to the present invention.

FIG. 2 is a plan view of the vanishing model casting apparatus according to the present invention.

FIG. 3 is a schematic configuration diagram of a foundry sand filling device.

FIG. 4 is an external perspective view of the vibration absorbing device.

FIG. 5 is a schematic configuration diagram of a foundry sand filling device.

FIG. 6 is a schematic configuration diagram of an unraveling device.

[Explanation of symbols]

 10 Casting Frame 11 Side Wall 12 Cavity (Suction Mechanism) 13 Sand Storage Section 14 Opening (Suction Mechanism) 15 Wire Mesh (Suction Mechanism) 16 Vinyl Sheet (Airtight Sheet) 17 Cast Sand 18 Vinyl Sheet (Airtight Sheet) 20A to 20D Disappearing Model Group (Disappearance model) 63 Casting box (casting box)

Claims (5)

[Claims] 1. A vanishing model casting apparatus in which a vanishing model is embedded in foundry sand contained in a casting frame, wherein the vane is a top and bottom open frame surrounded by side walls and the inside of which is a sand container. , A suction mechanism which is provided on the side wall of the flask and sucks gas in the sand container, and is arranged above and below the flask in which the sand container is filled with molding sand, and the suction mechanism allows the inside of the sand container to be removed. An airtight sheet that is brought into close contact with the foundry sand by sucking gas, and a disappearance model casting device. 2. The suction mechanism sucks the gas in the sand containing portion to bring the airtight sheets arranged above and below the casting frame into close contact with the molding sand filled in the sand containing portion. The vanishing model casting according to claim 1, characterized in that the vanishing model which has been previously embedded in the casting mold cannot be detached from the casting frame, and the casting frame, the casting sand and the vanishing model are separated and integrally moved. How to move the device. 3. A casting mechanism in which the vanishing model casting device sucks gas in the sand containing portion to bring the airtight sheets arranged above and below the casting frame into close contact with the foundry sand filled in the sand containing portion. A method for casting a disappearing model, which comprises solidifying sand, and then pouring it to replace the disappearing model previously buried in the casting sand with a molten metal and cooling and solidifying to form a casting. 4. The suction mechanism sucks the gas in the sand container to bring the airtight sheets arranged above and below the casting frame into close contact with the molding sand filled in the sand container, and the molding sand and this casting. The casting model formed by replacing the vanishing model that was previously buried in the sand with the molten metal cannot be removed from the casting frame, and the casting frame and the casting sand and the casting can be separated and integrally moved. The method for moving the vanishing model casting device according to claim 1. 5. A net-shaped casting receiver is prepared, and the vanishing model casting device in which the casting is buried in casting sand is arranged on the casting receiver, and the airtight sheet attached to the lower part of the casting frame is placed. The solution of the vanishing model casting apparatus according to claim 1, wherein the casting sand contained in the sand container is loosened and dropped into a casting receiver so that the casting is received by the casting receiver. Frame method.