JPH07185740A - Molding machine - Google Patents

Abstract

PURPOSE:To improve the filling degree of molding sand by providing an air supplying hole being communicatable with an air supplying hole of a cover member and arranging an air supplying tank communicated with a compressed air source. CONSTITUTION:The cover member 14 and a sand charging hopper 15 are arranged so as to be possible to insert/separate and asend/descend at the upper part of a molding flask 11. Plural segment weights 20 having the total area ratio at 70-98% to the inner area of the molding flask 11 are hung down so as to be possible to ascend/descend through hanging levers 19 in the cover member 14. Plural through-holes vertically penetrated so as to be adjustable to the whole opening area at the upper end are arranged at each segment weight 20. The air supplying hole 24 being possible to communicated with the air supplying hole 16 is provided at the upper part of the cover member 14, and the air supplying tank 25 communicately connected with the compressed air source is arranged. By this constitution, the filling degree over the vertical direction of the mold can be uniformized. while finely adjusting the ratio of the acting air quantity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for forming a mold by causing compressed air to flow through molding sand supplied to a space defined by a flask and a model plate and pressurizing it with a squeeze hood.

[0002]

2. Description of the Related Art Conventionally, as a mold making apparatus as described above, compressed air is made to flow through the molding sand supplied to the space defined by the molding frame and the model plate, and the vicinity of the model plate (casting A device for enhancing the filling degree of the molding sand in the lower part of the frame and thereafter compressing the molding sand from the upper portion of the molding sand with a segment squeeze hood to obtain the required filling degree for the entire molding sand is disclosed in Japanese Patent Laid-Open No.
It is disclosed in Japanese Patent Publication No. 35123. However, in the molding of such a mold, a step of compressing the molding sand by the segment squeeze hood is required in addition to the step of increasing the filling degree of the molding sand near the model plate by allowing compressed air to flow through the molding sand. There is a problem that the manufacturing process becomes high because the process becomes long and a large amount of each auxiliary equipment is required.

In order to solve such a problem, a plate member (including one divided into a plurality of parts) having air permeability is placed on the top of the foundry sand, and compressed air is supplied from above the plate member having air permeability. Is disclosed in Japanese Patent Laid-Open No. 58-17305, in which the mold sand is molded by increasing the filling degree of the molding sand by the action of fluidizing the molding sand and the impact pressure acting on the molding sand.
No. 6, for example. When molding such a mold, the lower the amount of air that passes through the plate member and into the molding sand, the better the lower part of the mold (at the part where the plate member is divided into multiple parts) is filled. On the contrary, the larger the amount of air acting on the upper surface of the plate member, the better the filling of the upper portion of the casting frame.

Therefore, if the ratio of these air amounts can be adjusted appropriately, it is possible to mold a mold having a uniform filling degree above and below the flask. However, in the above-described mold making apparatus, once a plate member having air permeability is installed, there is a problem that the ratio between the amount of compressed air passing through this plate member and the amount of air acting on the plate member cannot be changed. The present invention has been made in view of the above problems, and it is possible to increase the filling degree of the molding sand by the synergistic effect of fluidizing the molding sand by the supply of compressed air and the pressure function of the pressure member. It is an object of the present invention to provide a mold making in which the ratio of the amount of working air can be finely adjusted as well as making the most of it, and an effective squeeze is formed by applying pressure by a pressure member.

[0005]

In order to achieve the above object, a mold making apparatus according to the present invention has a vent hole at the top.
A model frame with a ruler is attached and a casting frame is provided at a position directly above the table so that the model frame can be moved up and down. An upper end of the frame is provided directly above the table at a position above the table. Cover with air supply port that can surround the opening by providing a space
A member and a sand container hopper are arranged so that they can be moved in and out and can be moved up and down, and a plurality of segment weights having a total area ratio of 70 to 98% with respect to the inner area of the flask are suspended in the cover member. Each segment weight is hung so that it can be lifted up and down, and a plurality of vertical through holes are provided in each segment weight so that the overall opening area of the upper end of the segment weight can be adjusted, and the air supply of the cover member is provided above the cover member. It is characterized in that an air supply tank is provided which has a supply port which can communicate with the port and which is communicatively connected to a compressed air source.

[0006]

According to the present invention, by adopting the above-mentioned solution means, the casting frame, the cover member and the air supply tank are mounted with the segment weight placed on the upper portion of the molding sand supplied into the casting frame. By integrally superimposing and clamping and supplying compressed air from the air supply tank into the cover member, a part of the compressed air flows through the space between the segment weights and the communication holes of the segment weights and flows into the molding sand. The exhaust air is discharged from the vent hole of the model plate to increase the filling degree of the molding sand in the vicinity of the model plate and at the same time, the remaining compressed air supplied into the cover member acts on the upper surface of the segment weight and rapidly moves the segment weight downward. The weight of the segment weight and the lifting force of the segment weight to increase the filling degree of the molding sand in each part corresponding to the segment weight at the upper position of the casting frame. Overall for vertically uniform degree of filling. In addition, the ratio of the amount of air flowing into the foundry sand to the amount of air acting on the upper surface of the segment weight is adjusted to the optimum state by closing the communication hole of the segment weight with a plug or removing the plug to make an optimal adjustment. Is performed.

[0007]

Embodiments of the present invention will now be described in detail with reference to the drawings. In FIG. 1, a base 2 is provided with a cylinder 2 facing upward, and a piston rod 3 has a box-shaped (concave) table 5 having an exhaust port 4 on a side surface at a tip thereof.
A model plate 7 having a vent hole 6.6 penetrating vertically is attached to the upper part of the table 5 to which is fixed. Also, columns 8.8 are erected at the four corners on the base 1,
At the middle position of the column 8.8, two rows of hollow roller conveyors 9 and 10 extending in the left-right direction are vertically installed at a required interval, and the bottom hollow roller conveyor 10 has a casting frame 1
1 is movably mounted. Further, a filling frame 12 is disposed above the hollow roller conveyor 10 so as to be capable of rising through supporting means 13, 13 fixed to a column 8.8.

Further, a cover member 14 and a sand container hopper 15 which can surround the upper end opening portion of the filling frame 12 with a space provided thereon are movably mounted on the upper-stage hollow roller conveyor 9, both of which are provided. Is horizontally connected so that it can move up and down independently for some distance. An air supply port 16 for taking in compressed air is provided on the upper surface of the cover member 14, and a number of ventilation holes 17A for passing compressed air are provided at a lower position in the cover member 14. Board 1
7 is provided. As shown in FIG. 3, a large number of suspension rods 19, 19 each having a locking piece 18 fixed to the upper end thereof are suspended in the perforated plate 17 so as to be vertically slidable, and the suspension rods 19, 19 are provided at the lower ends thereof. Disc-shaped segment weights 20 and 20 are fixed, and the segment weights 20 and 20 are shown in FIGS.
As shown in, they are regularly arranged vertically and horizontally at appropriate intervals.

Further, each segment weight 20, 20 is formed with a communication hole 21, 21 penetrating vertically.
The upper ends of the communication holes 21, 21 are closed by removable plugs 22, 22. Also in the above column 8.
A frame-shaped ceiling frame 23 is installed between the upper ends of the air supply tanks 8, and an air supply tank 25 having a supply port 24 communicating with the air supply port 16 on the lower surface is suspended from the ceiling frame 23. An opening / closing valve 26 for opening / closing the supply port 24 is provided in the air supply tank 25, and the air supply tank 25 is connected to a compressed air source (not shown). 15A in the figure
Is a cylinder for operating the louver 15B of the sand container hopper 15.

In the thus-constructed structure, the cylinder 2 operates in the state shown in FIG. 1 to raise the model plate 7 so that the casting frame 11 and the filling frame 12 are superposed and the raising is temporarily stopped. Next, the cover member 14 is moved outwardly from the position directly above the filling frame 12 and the sand hopper 15 is moved to a position just above the filling frame 12, and the cylinder 15A operates to open the louver 15B. The foundry sand in the sand hopper 15 is thrown into the space defined by the model plate 7, the casting frame 11, and the fill frame 12. Subsequently, after the sand container hopper 15 is moved outward and the cover member 14 is moved to a position directly above the fill frame 12, the cylinder 2 is further extended to raise the table 5 and the like to raise the fill frame. The cover member 14 is placed on the cover 12, and the cover member 14 is brought into contact with the lower surface of the air supply tank 25 to supply the air to the air supply port 16.
And the supply port 24 are airtightly connected. During this time, the segment weight 20 is placed on the upper portion of the foundry sand in the filling frame 12, and when it is further pushed up to bring the filling frame 12 and the cover member 14 into contact with each other, as shown in FIG. It is pushed up near the bright plate 17.

In this state (see FIG. 2 below), the opening / closing valve 26 is separated from the supply port 25, and the compressed air stored in the air supply tank 25 suddenly flows into the cover member 14 and flows through the vent hole 17A. As a result, a part thereof flows through the space between the segment weights 20, 20 and the communication holes 21, 21 which are not blocked by the plugs 22 in the segment weight 20, to the upper surface of the molding sand, and penetrates the molding sand to form the vent hole 6 Also, the filling degree of the foundry sand in the vicinity of the model plate 7 that is exhausted through the exhaust port 4 is increased. At the same time, the remaining compressed air supplied into the cover member 14 acts on the upper surfaces of the segment weights 20, 20 and the segment weight 2
0, 20 is pushed down rapidly and the weights of the segment weights 20, 20 and the pushing-down impact force make castings of the respective parts corresponding to the segment weights 20, 20 at the upper position of the casting frame (including the fill frame 12). The filling degree of sand is increased so that the filling degree of the entire mold is uniform in the vertical direction.

Next, after closing the opening / closing valve 26 to stop the supply of compressed air, the cylinder 2 is reversely operated (contracting operation) to lower the table 5. As a result, the cover member 14 is first placed on the hollow roller conveyor 9, and then the filling frame 1
2 is placed on the supporting means 13 and 13, and the casting frame 11 containing the mold is placed on the punching roller conveyor 10 so that the casting mold is separated from the model plate 7. The above-mentioned operation is repeated by moving the la conveyor 10 outward and the empty flask 11 is carried over the model plate 7 and returned to the state of FIG.

The relationship between the segment weights 20 and 20 and the inner area of the flask and the filling degree of the mold, which are obtained by various experiments, will be described. Each segment weight 20, 2
When the total area of 0 is set to 70 to 98% of the inner area of the flask and the sand surface pressure against the molding sand in the flask is set to 20 to 100 g / cm ² , a mold having a substantially uniform vertical and high hardness can be produced. . That is, the smaller the total area of the lower surfaces of the segment weights 20, 20 is with respect to the inner area of the casting frame, the more compressed air flows into the molding sand and well fills the lower molding sand. The larger the total area of, the more the air resistance acting on the upper surface of the weight increases, the downward acceleration of the weight and the downward inertia force increase the downward compression of the foundry sand, and the upper part of the sand is well filled and the ratio is In the case of 70 to 98%, it means that the entire molding sand can be filled almost uniformly. In addition, the compression ratio of the molding sand in the molding of the mold is such that the inflow of compressed air and the working ratio are slightly changed according to the height of the molding frame, (height of the molding sand), etc. to make the filling degree of the entire mold uniform. It is necessary to adjust the plugs 22 and 22 by appropriately attaching or detaching the plugs 22 and 22 to the communicating holes 21 and 21 and changing the overall opening area of the upper ends of the communicating holes 21 and 21 to perform a test operation.

Further, the structure shown in FIGS. 5 and 6 may be used to adjust the opening area of the communication holes 21, 21. That is, holes 30A and 30A corresponding to a large number of communication holes 21 and 21 are bored in the upper part of the segment weight 20 in which a plurality of communication holes 21 and 21 are bored, and adjacent holes 30A and 30A are partly elongated holes. 30B, 30B
When adjusting the inflow amount of compressed air by stacking the perforated slide plates 30 continuous with each other by screwing the perforated slide plates 30 into the communication holes 21 through the bolts 30C in the elongated hole 30B portion. Alternatively, the bolt 30C may be loosened and the hole slide plate 30 may be slightly displaced to adjust the overall opening area of the upper ends of the communication holes 21 and 21 to re-tighten the bolt 30C.

[0015]

As is apparent from the above description, the present invention provides a plurality of segment weights having a total area ratio of 70 to 98% with respect to the inner area of the flask in the cover member for flowing air pressurization. It is hung up and down via a suspension rod, and each segment weight has a plurality of vertical through holes that can adjust the overall opening area.Thus, the casting sand is fluidized by the supply of compressed air. It is possible to increase the filling degree of the foundry sand by the co-operation of the action of the pressurizing member and the action of the pressurizing member (segment weight), and to finely adjust the ratio of the working air amount to fill the mold to be molded up and down. The degree can be uniform.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view showing an operating state of FIG.

FIG. 3 is an enlarged sectional view of a segment weight member in a cover member.

FIG. 4 is a view on arrow AA in FIG.

FIG. 5 is a plan view showing another embodiment of the segment weight.

6 is a sectional view taken along the line BB in FIG.

[Explanation of symbols]

 5 table 6 vent hole 7 model plate 11 casting frame 14 cover member 15 sand hopper 16 air supply port 19 suspension rod 20 segment weight 21 communication hole 22 plug 24 supply port 25 air supply tank 30 hole slide plate 30A Hole 30B Slotted hole 30C Bolt

Claims (1)

[Claims] 1. A position directly above a table 5 having a model plate 7 with a vent hole 6 attached to the upper part thereof and capable of moving up and down,
A casting frame 11 is provided so as to be able to enter and exit, and at a position immediately above the table 5 above the casting frame 11, an air supply port 16 is provided which is capable of surrounding the upper end opening of the casting frame 11 with a space portion. The cover member 14 and the sand container hopper 15 are arranged so as to be able to move in and out, and the cover member 14 has a total area ratio of 70 to 98% with respect to the inner area of the casting frame 11. A plurality of segment weights 20 are hung vertically via suspension rods 19, and each segment weight 20 is provided with a plurality of vertically penetrating communication holes 21 capable of adjusting the overall opening area of the upper end thereof. 14 above the cover.
An air supply tank 25 that has an air supply port 24 that can communicate with the air supply port 16 of the member 14 and that is in communication with a compressed air source.
A mold making apparatus characterized by arranging