WO2000059659A1

WO2000059659A1 - Method for separating green sand mold and as-cast product and apparatus therefor

Info

Publication number: WO2000059659A1
Application number: PCT/JP2000/002101
Authority: WO
Inventors: Osamu Masuno; Ryoji Kanayama; Kuniyasu Mori; Shigeaki Yamamoto; Kimikazu Kaneto; Hiroaki Tokita; Yasushi Ono; Kazuo Sugimoto; Hisashi Harada; Takehiko Matsumoto; Yasunori Yoshida
Original assignee: Sintokogio, Ltd.
Priority date: 1999-04-01
Filing date: 2000-03-31
Publication date: 2000-10-12
Also published as: EP1092491A4; EP1092491A1

Abstract

A method for separating a green sand mold and an as-cast product which comprises surrounding gas-tightly a green sand mold without a mold flask having been supplied with a melt and aspirating steeply the inside of a structure surrounding the sand mold gas-tightly so as to reduce the pressure thereof to a pressure of -200 mmHg as expressed in gauge pressure or less within a period of 0.5 seconds and to a pressure of -360 mmHg or less finally, thereby reducing the boiling temperature of the water being present within the whole green sand mold including a condensed water layer formed around the as-cast product in the green sand mold, to bring this water to boil, which results in the break of the green sand mold and in the separation from the as-cast product. After the break of the sand mold, the above structure is brought back to an ordinary pressure and the as-cast product is taken out. The method can be used for securing the separation of an as-cast product from a green sand mold and the break of the green sand mold.

Description

Technical field Separation method of raw sand mold and animal material and its equipment

The present invention relates to a method and an apparatus suitable for separating a raw material from a poured hot sand mold. Background art

Conventional methods of separating the raw sand mold from the raw material by disintegrating the poured green sand mold with the frame include, for example, extracting the green sand mold from the inside of the frame and letting the green sand mold fall by gravity. When the green sand mold collapses due to the weight and vibration of the green sand mold using a vibrator or vibrator, the green sand mold collapses and separates, wedge-shaped protrusions are inserted into the green sand mold when extracting the green sand mold from the frame A device that breaks and separates the green sand mold using the impact of applying a mechanical external force, etc., ③ 鎵 Remove the green sand mold from the frame, and then put the green sand mold into a rotating drum or vibrating drum to mold it. What breaks and separates by using the weight and head of a material or the vibration and heat of a material is generally known.

However, all of these conventional methods apply a large impact to raw sand-type animal materials to separate them, and the contact with other animal materials also overlaps, causing the animal material to crack, chip, This causes defects such as dents and deformation. In addition, in recent years, due to the demand for complicated material shapes and high-precision dimensions, high-hardness and high-strength green sand molds have been molded and molded. The necessity of separating the raw materials is increasing.

In addition, since the high-strength green sand mold described above has poor disintegration, the raw material is not sufficiently separated from the green sand and is sent to the subsequent process with the green sand adhered. Therefore, sand recovery in a green sand type production plant that uses green sand repeatedly is deteriorated. In addition, the cost of green sand increases and core sand is mixed into the recovered sand, making the sand treatment process difficult. In addition, the history of each raw material is unclear because a plurality of raw materials flow simultaneously to the post-processing step. Due to this, the raw material is defective When such a problem occurred, it was difficult to identify various conditions, and it was difficult to take sufficient measures.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method and an apparatus for surely separating a raw material from a green sand mold and collapsing the green sand mold. ₀ Disclosure of the Invention

In order to achieve the above object, the present invention provides a method for separating a raw material from a poured sand mold. This method involves the steps of hermetically enclosing a poured green sand mold without a frame and the inside of a structure that hermetically encloses this green sand mold within 0.5 sec within -20 O mm Hg or less. The pressure inside the structure is finally reduced to a pressure lower than -36 OmmHg by suction and decompression, and the moisture condensate layer formed around The process of lowering the boiling point of the moisture in the whole green sand mold containing water to boil the water, disintegrating the green sand mold and separating it from the animal material, And a step of taking out. In general, a layer of so-called moisture condensate, which is formed by the heat of the raw material in a higher temperature than other parts of the green sand and a large amount of water is formed around the raw material in the green sand type, Low strength. For this reason, in the present invention, the green sand mold without the molten metal frame that has been poured is hermetically surrounded, and the inside of the structure that hermetically surrounds the green sand mold is subjected to a pressure of −20 O within 0.5 sec. If the pressure inside the structure is finally reduced to a pressure lower than 16 O mmHg with a gauge pressure, the boiling point of the water will decrease, and the boiling point of the water will decrease. Moisture in the high-temperature state heated to the raw material boils, and as a result, the green sand mold collapses and is separated from the raw material. Then, release the negative pressure and remove the raw material. Placing the sand mold in such a negative pressure state is such that if the suction is depressurized slowly, the gas due to boiling will slowly diffuse out of the sand mold, and no force will be generated to rapidly collapse the sand mold. This is because a rapid decompression rate of less than 120 OmmHg at gage pressure within 0.5 sec is required, and it is higher than the pressure of 36 OmmHg at gage pressure. At reduced pressure, boiling does not occur enough to collapse the green sand mold, — It is necessary to place the green sand mold in an atmosphere decompressed below a pressure of less than 36 OmmHg.

In the method for separating a green sand mold from a raw material according to claim 1, a green sand mold without a frame that has been poured is a green sand mold with a frame immediately after molding. It is the one that has been separated, or the one that has just been molded without a frame. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a front view showing one embodiment of the present invention. FIG. 2 is a diagram illustrating the operation of the embodiment of FIG. 3 and 4 are explanatory diagrams of the operation of the main part in FIG. FIG. 5 is a graph showing the pressure state in the structure with respect to the elapsed time of the suction pressure reduction. FIG. 6 is a front view showing a second embodiment of the present invention. FIG. 7 is a diagram for explaining the operation of the apparatus of the embodiment shown in FIG. FIG. 8 is an enlarged plan view of a main part of the device of the embodiment of FIG. FIG. 9 is an enlarged front view of a main part of the apparatus of the embodiment of FIG. FIGS. 10 and 11 are explanatory diagrams of the operation of the main part of the apparatus of the embodiment of FIG. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. As shown in Fig. 1, the device that separates the raw material from the poured green sand mold is divided into an airtight surrounding means 1 for airtightly surrounding a poured green sand mold without a frame, and an airtight surrounding means 1. Suction means 2 that sucks and decompresses the interior of the space created to create a negative pressure state and maintains the negative pressure state for a certain period of time, and a product that removes the negative pressure state and removes the raw material from the collapsed green sand mold Material take-out means 3 and

As shown in FIG. 1, the airtight surrounding means 1 includes a box-shaped tray 5 configured to be able to move up and down by an upward cylinder 4, and an inverted mounting fixedly disposed just above the tray 5. The tray 5 is provided with a 、 -type placing member 7 for placing a green sand mold, which is formed by arranging a plurality of strips in the left-right direction. The tray 5 and the 錡 -shaped mounting member 7 are rotated counterclockwise to tilt to the angle at which the sand mold or the like slides down.The cover 6 has a pressure detection mechanism 2 that detects the internal pressure. 6 is attached, and a seal member 2 7 Is buried. Further, the suction means 2 is connected to the cover 6 in communication, and the suction means 2 comprises an on-off valve 8, a conduit 9, and a vacuum source 10.

Further, the animal material taking-out means 3 includes a fork member 11 configured to be movable left and right, vertically movable and horizontally rotatable, and a drive mechanism 12 for horizontally moving, vertically moving and horizontally rotating the fork member 11, It consists of.

The reference numeral 13 in the figure denotes a transport device for transporting the vertical sand mold 15 with an upper and lower frame 14 in the horizontal direction, which is mounted on the traveling vehicle 16 that can reciprocate left and right and the traveling vehicle 16. And a lifting mechanism 17 for lifting the upper and lower frames 14. Also. Reference numeral 1 8 denotes an extracting device for extracting the upper and lower green sand molds 15 from the upper and lower frames 14, and a frame-shaped mounting table 19 on which the upper and lower frames 14 are placed, and the upper and lower green sand molds 1 5 into upper and lower frames 1. It is composed of a pull-out mechanism 20 that pulls out from 4, and a horn that prevents the upper and lower frame 14 from rising. Reference numeral 23 denotes a surface plate trolley on the cooling line, and reference numeral 24 denotes a collection chute.

Next, the operation of the above configuration will be described. Pouring upper and lower 注 frames 1 4 on the cooling line of the production line on the surface plate carrier 2 3 Then, the upper and lower green sand molds 15 containing the raw materials 25 are transferred to the upper and lower frames 1 4 by the extraction mechanism 20 of the extracting device 18. Pull out from inside. Next, the upper and lower green sand molds 15 extracted from the upper and lower frames 14 are extruded onto the 铸 -shaped placing member 7 of the airtight surrounding means 1 by the extruder 22, and then the cylinder 4 of the airtight surrounding means 1 is extended. Then, the mold placing member 7 on which the upper and lower sand molds 15 are placed is raised, and the sealing members 27 are brought into contact with the tray 5, and as shown in FIG. Cover hermetically with a hippopotamus.

Generally, as shown in Fig. 3, the temperature of the raw material 25 in the upper and lower raw sand molds 15 is higher than the other parts of the upper and lower raw sand molds 15 due to the heat of the raw material 25. The water condensed layer 28 has a small strength. For this reason, while detecting the pressure inside the cover 6 with the pressure detecting mechanism 26, the on-off valve 8 of the suction means 2 is opened, and the airtight space defined by the tray 5 and the cover 6 is rapidly suctioned and depressurized. To make the space negative pressure. In other words, as shown in FIG. 5, the pressure inside the structure forming the space is increased by a gauge pressure within 200 sec. The pressure is rapidly reduced to a pressure of not more than mmHg, and the space is finally depressurized to a pressure lower than -36 O mmHg by a gauge pressure (hereinafter, the pressure is also referred to as a gauge pressure). Such depressurization is carried out slowly because if the suction is depressurized slowly, the gas due to boiling gently diverges from the green sand mold and no force is generated to rapidly collapse the green sand mold. This is because a rapid pressure reduction rate of not more than —20 O mmHg is required within 0.5 sec. Also, at a reduced pressure higher than —36 O mm H g, sufficient boiling does not occur to collapse the green sand mold. When the pressure in the space is reduced in this manner, the boiling point of the entire water-containing sand type 15 containing water in the water condensing layer 28 lowers, and this water boils. As a result, the raw sand type 15 collapses.分離 Separate from material 25 (see Fig. 4). The collapsed fresh sand mold pieces accumulate on tray 5. Since the core does not collapse due to boiling of water, it remains in the raw material 25 and does not mix with the raw sand mold pieces.

Next, after closing the on-off valve 8, the atmospheric pressure return valve (not shown) attached to the cover 6 is opened to return the inside of the cover 6 and the like to the atmospheric pressure, and then the cylinder 4 is contracted to operate. Lower tray 5, upper and lower sand type 15 and animal material 25. Next, the drive mechanism 12 of the animal material take-out means 3 is driven to move the fork member 11 leftward, and the fork member 11 is moved under the animal material 25, and then the drive mechanism Drive 1 2 to raise the fork member 1 1, and lift the animal material 25 from the 載 -shaped placing member 7. Next, the drive mechanism 12 is driven to move the raw material 25 to the right by the fork member 11, and then the raw material 25 is transported to the post-processing step. Then, the tray 5 and the 錡 -shaped placing member 7 are tilted to discharge the green sand mold pieces deposited on the tray 5 and the 錡 -shaped placing member 7 onto the collection rod 24 and conveyed to the sand processing line.

In the above embodiment, the poured green sand mold without a frame has a frame immediately after molding, and after pouring, the upper and lower green sand molds with a frame are removed from the upper and lower frames. It is manufactured by being ejected and separated, but is not limited to this.For example, a green sand mold that has been molded by a so-called blanking type molding machine and has a state immediately after molding without a frame can be used. However, a similar effect can be obtained. In this case, the upper and lower sand molds are generally equipped with a jacket when pouring. Also, in the above embodiment, the green sand mold without the 銬 frame after the pouring is a horizontal split vertical sand mold, but is not limited to this. Instead, for example, the same operation and effect can be obtained by pouring the molten metal in a state where the above-mentioned upper and lower raw sand molds are set up.

As is clear from the above description, the invention of claim 1 is a method for separating a raw material from a poured green sand mold, and a step of hermetically surrounding a poured green sand mold without a frame. Then, the inside of the structure that hermetically surrounds the green sand mold is rapidly suctioned and depressurized to a pressure of −20 O mm Hg or less within 0.5 sec. The pressure is reduced to a pressure lower than 6 OmmHg, thereby lowering the boiling point of the moisture in the entire green sand mold including the moisture in the water condensed layer formed around the raw material in the green sand mold to reduce this moisture. Boil, disintegrating the green sand mold to separate from the raw material, and removing the raw material after releasing the airtightly enclosed state. Easy and reliable separation of raw material and green sand mold and collapse of green sand mold without causing Next, a second embodiment of the present invention will be described with reference to FIGS. 6 to 11. As shown in FIG. 6, the apparatus for separating the raw material from the poured green sand mold has a supporting means 40 for supporting the poured green sand mold with a minimum contact area with the raw sand mold. Is provided. The other means are the same as the means denoted by the same reference numerals in FIG. The support means 40 is composed of a plurality of rod members 45 erected on the upper surface of a box-shaped tray 5 described later. The tray 5 and the rod member 45 rotate counterclockwise and tilt to an angle at which the sand mold or the like slides down.

As shown in FIGS. 8 and 9, among the plurality of rod members 45, 45 a located at the center and the periphery of the tray 5 is long (FIG. 9), and at least three of these 45 a are provided. For example, a green sand mold can be placed and supported. Further, the remaining 45b of the plurality of rod members 45 is slightly shorter than the rod member 45a, and can support the animal material placed on the upper end after the green sand mold collapses. Yes (Figure 9).

Further, the support means 40 has a support auxiliary mechanism 30 for receiving and temporarily holding the green sand mold when the green sand mold is fed into the support means 40. The supporting auxiliary mechanism 30 is composed of a supporting member 31 extending in the horizontal direction by sewing between the rod members 45, and an upward cylinder 32 for moving the supporting member 31 up and down. The support member 31 forms the upper end of the plurality of rod members 45 by the expansion and contraction operation of the cylinder 32. You can come and go from the horizontal level.

Next, the operation of the above configuration will be described. The cylinder 32 of the support auxiliary mechanism 30 shown in FIG. 6 is extended and the support member 31 is raised above the horizontal level formed by the upper end of the rod member 45. Under this condition, the upper and lower raw sand molds 15 containing the animal material 25 are extracted from the upper and lower frames 14 by the extracting mechanism 20 of the extracting device 18.

Next, the upper and lower green sand molds 15 extracted from the upper and lower frames 14 are extruded onto the support members 3 1 by the extruder 22, and then the cylinder 3 2 is contracted to operate the upper and lower green sand molds 15 and the support members. 3 Lower 1 etc., and put the upper and lower sand molds 15 on the upper end of the rod member 45. Next, the cylinder 4 of the airtight surrounding means 1 is extended and the rod member 45 on which the upper and lower sand molds 15 are mounted is raised, and the sealing member 27 is brought into contact with the tray 5 as shown in FIG. The upper and lower raw sand molds 15 are hermetically surrounded by the tray 5 and the cover 6.

As in the first embodiment, generally, as shown in FIG. 10, around the raw material 25 in the upper and lower raw sand mold 15, the heat of the raw material 25 increases the A layer (moisture condensed layer) 28 is formed in which a higher amount of moisture is collected at a higher temperature than in other parts, and the water condensed layer 28 has low strength. Therefore, while detecting the pressure in the cover 6 with the pressure detecting mechanism 26, the on-off valve 8 of the suction means 2 is opened, and the pressure is rapidly reduced from the airtight space defined by the tray 5 and the cover 6. To make the space negative pressure. For example, similarly to the first embodiment, as shown in FIG. 5, the pressure inside the structure forming the space is rapidly increased to less than 120 OmmHg within 0.5 sec. The space can be finally depressurized to a pressure lower than the pressure of 16 OmmHg. By doing so, the boiling point of the water in the entire upper and lower raw sand mold 15 containing the water in the water condensing layer 28 is lowered, and this water is boiled. At this time, the upper and lower fresh sand molds 15 are supported by the tips of the rod members 45 with the contact area with them as small as possible, so that the undergrowth sand molds are supported in a state where they easily collapse. As a result, the upper and lower sand molds 15 are easily and reliably collapsed and separated from the animal material 25 (see Fig. 11). The collapsed green sand mold pieces accumulate on the tray 5. Since the core does not collapse due to boiling of water, the core remains in the raw material 25 and does not mix with the green sand mold pieces. Next, after the on-off valve 8 is closed, the atmospheric pressure return valve (not shown) attached to the cover 6 is opened to return the inside of the cover 16 to the atmospheric pressure, and then the cylinder 4 is contracted to operate. Lower tray 5, upper and lower sand type 15 and animal material 25. Next, the drive mechanism 12 of the animal material take-out means 3 is driven to move the fork member 11 leftward, and the fork member 11 is moved under the animal material 25, and then the drive mechanism 1 2 is driven to raise the fork member 1 1 to lift the animal material 25 from the rod member 45. Next, the drive mechanism 12 is driven to move the raw material 25 to the right by the fork member 11, and then the raw material 25 is transported to the post-processing step. Thereafter, the tray 5 and the rod member 45 are tilted to discharge the green sand mold pieces deposited on the tray 5 and transported to the sand processing line.

In the second embodiment, the poured raw sand molds 15 are drawn out of the upper and lower frames 14 after pouring, and are in a state without frames. However, the present invention is not limited to this. In other words, the same operation and effect can be obtained even with the frame. In addition, in the second embodiment, the upper and lower green sand molds 15 without pouring, which have been poured, are the upper mold and the lower mold, but the invention is not limited to this. A similar effect can be obtained with the upper mold.

As is clear from the above description, the method for separating the raw material from the poured green sand mold according to claim 6 supports the poured green sand mold with the contact area with the green sand mold as small as possible. And the step of rapidly suctioning and reducing the pressure inside the airtightly enclosed structure to a negative pressure state, thereby forming the moisture in the water condensing layer formed around the raw material in the green sand mold. Lowering the boiling point of the water content of the entire green sand mold to boil the water, thereby disintegrating the green sand mold and separating it from the raw material; and after releasing the airtightly enclosed state. Since the process has a step of taking out the raw material, the separation of the raw material from the green sand mold and the collapse of the raw sand mold can be easily and reliably performed without causing the fatigue of the raw material. Such as being able to do Play.

Claims

の of Ί s

A method for separating animal material from a poured sand mold,

A step of hermetically surrounding the poured green sand mold,

Within 0.5 sec, the inside of the airtight surrounding structure is rapidly aspirated and reduced to a pressure of 200 mmHg or less, and finally the inside of the structure is 360 mmHg. Reducing the pressure to a lower pressure, thereby lowering the boiling point of the water in the entire green sand mold including the water in the water condensing layer formed around the raw material in the green sand mold, and boiling the water; A method of separating the green sand mold and the animal raw material, comprising: a step of collapsing the green sand mold to separate the raw material from the animal material; and a step of removing the animal material after the airtightly enclosed state is released. .

A method for separating animal material from a poured sand mold,

A process of hermetically surrounding the poured green sand mold without a frame,

The inside of the structure that hermetically surrounds the green sand mold is rapidly suctioned and depressurized to a pressure of −20 O mmHg or less within 0.5 sec. The pressure is reduced to a pressure lower than mmHg, thereby lowering the boiling point of the water in the entire green sand mold including the water in the water condensed layer formed around the raw material in the green sand mold, thereby boiling the water. Disintegrating the green sand mold to separate from the raw material;

Removing the animal material after the airtightly enclosed state is released, and a method of separating the green sand mold from the animal material.

3. The method for separating green sand mold and animal material according to claim 2,

The poured green sand mold without frame is a green sand mold separated from the inside of the green sand mold with the frame immediately after molding. Separation method.

The method for separating a green sand mold from a raw material, wherein the poured green sand mold without a frame does not have a green frame immediately after molding.

The method for separating a green sand mold from a raw material according to any one of claims 2 to 4, The method for separating a green sand mold from a raw material, wherein the poured green sand mold without a frame is in a half-split state.

A device for separating animal material from a poured sand mold,

Airtight surrounding means for airtightly surrounding the poured raw sand mold without frame,

The space defined by the airtight surrounding means is rapidly suctioned and depressurized to a pressure of not more than -20 OmmHg within 0.5 sec, and finally this space is lower than -36 OmmH. Suction means for reducing the pressure to a pressure,

A method for removing the raw material from the raw sand mold that has collapsed as the negative pressure state is released;

An apparatus for separating green sand molds and animal materials, comprising:

A device for separating animal material from a poured sand mold,

Airtight surrounding means for airtightly surrounding the poured green sand mold,

The space defined by the airtight surrounding means is rapidly suctioned and depressurized to a pressure of 200 mmHg or less within 0.5 sec, and finally this space is decompressed from 36 OmmHg. Suction means for reducing the pressure to a low pressure;

An apparatus for separating green sand molds and animal materials, comprising:

A method for separating animal material from a poured sand mold,

A process of supporting the poured green sand mold with the contact area with the mold as small as possible and hermetically surrounding the mold;

The whole of the green sand mold including the moisture of the water condensing layer formed around the raw material in the green sand mold by rapidly suctioning and depressurizing the inside of the hermetically surrounding structure to a negative pressure state. Lowering the boiling point of the water to boil the water, thereby breaking down the raw sand mold and separating it from the raw material;

Removing the animal material after the airtightly enclosed state is released, and a method for separating the green sand mold and the animal material.

The method for separating raw sand mold and animal material according to claim 8,

Place the poured green sand mold on the tips of a plurality of vertically extending rod members to support it. A method for separating raw sand molds and animal materials, which is characterized by holding.

10. In the method for separating green sand mold and animal material according to claim 8,

In the separating step, the inside of the hermetically surrounding structure is rapidly suctioned and depressurized to a pressure of −20 OmmHg or less within 0.5 sec, and the space is finally reduced to a pressure of −36 OmmHg or less. A method for separating green sand molds and animal materials, comprising a step of reducing pressure.

11. It is a device to separate the raw material from the poured sand mold,

A support means for supporting the poured green sand mold in a state in which the volume is as small as possible upon contact with the mold;

Airtight surrounding means for hermetically surrounding the poured green sand mold supported by the supporting means, and suction means for reducing the pressure inside the space defined by the airtight surrounding means by reducing the pressure by suction,

An apparatus for separating green sand molds and animal materials, comprising:

12. In the apparatus for separating raw sand mold and animal material according to claim 11,

Wherein the supporting means is a plurality of rod members that can be placed on the top end of the green sand mold that has been poured so as to extend in the vertical direction and that can support the raw sand mold. apparatus.

13. In the apparatus for separating green sand mold and animal material according to claim 11,

The suction means rapidly aspirates and depressurizes the space defined by the airtight surrounding means to a pressure of −20 OmmHg or less within 0.5 sec, and finally depressurizes this space to a pressure lower than −36 OmmHg. An apparatus for separating green sand and raw material, characterized in that: