JPH073846U - Air vent device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an air vent device capable of smoothly eliminating air in a mold for molding a core. [Structure] Bottom portions 24 and 44 of the recesses 2 and 3 of the inserts 21 and 41
Are provided with air passages 25 and 45, and the air passages 25 and 45 are
Disposed therein is a rod-like member 26 and 46 whose ends 27 and 47 are fixed to a fixed base 28 and 48. When the sand is filled here, the tip portion 27 of the rod-shaped member 26 is slightly offset from the bottom portion 24 of the insert 21 to the outside, and after shaping, the tip portion
The rod-shaped member 26 penetrates the air passage 25 so that the member 27 is located at a position projecting inward from the bottom 24 of the insert 21.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an air vent device for smoothly removing air in a mold, and more particularly to an air vent device for smoothly removing air in a mold for molding a core.

[0002]

[Prior art]

 When molding a core, particularly when molding a core having a convex portion such as a boss, molding is performed using an upper main mold, a lower main mold, a vise, and an insert. That is, the insert held by the insert vice cylinder is arranged between the upper main mold, the lower main mold, and the vise, and the molding space formed by the upper main mold, the lower main mold, the vise, and the insert is formed. Sand is filled with compressed air to mold the core.

[0003] Here, when the molding space is filled with sand to form the core, particularly when a convex portion is formed, the air filled with the sand is smoothly discharged from the mold. Need to be eliminated. That is, if air remains in the molding space, sand clogging may worsen and the core shape may not be molded.Therefore, for example, an air vent device for smoothly eliminating air may be provided at the bottom of the recess of the insert. It is provided.

[0004]

[Problems to be solved by the device]

 Here, as the core, there are a shell core, a cold box core, etc., but any of the cores contains an adhesive such as resin when the sand is filled. When the air passes through the air vent device, there is a possibility that the adhesive or the like adheres to the passage forming the air vent device and sand adheres to the passage to clog the air vent device.

When the air vent device is clogged, the air filled with the sand cannot be smoothly removed from the mold, and the air remains in the molding space. For example, the sand is left on the bottom of the recess of the insert. There is a possibility that the so-called sand clogging, where the core is not filled, becomes worse, the core shape is lost, and the quality deteriorates. For this reason, it is necessary to frequently perform cleaning work of the air vent device, and for this reason, it is necessary to secure work personnel, so that the manufacturing cost cannot be reduced. Further, since the air vent device cannot be completely removed only by blowing air, cleaning work must be performed using a brush or the like, which may hinder the improvement of productivity due to the execution of the cleaning work.

The present invention has been made in view of the above circumstances, and it is possible to smoothly remove the air in the mold for molding the core by cleaning the passage forming the air vent device with the rod-shaped member. An object is to provide a possible air vent device.

[0007]

[Means for Solving the Problems]

 Therefore, the present invention is an air vent device provided in a mold for molding a core by filling sand with a passage for removing the air in the mold to the outside and a tip at the time of sand filling. Even if the portion is deep from the outside, it fits into the modeling surface to close the passage with a predetermined gap, and after core molding, the tip projects from the outside to the inside of the modeling surface and penetrates the passage. And a rod-shaped member.

[0008]

[Action]

 When the molding space inside the mold is filled with sand to mold the core, the air is filled with the sand.In the air vent device with such a configuration, the air inside the mold is removed. A passage for removing the air is provided in the portion, and the air is removed to the outside through the passage. Further, at the time of sand filling, the rod-shaped member is fitted into the passage from the outside until the tip reaches the shaping surface even if the tip is deep, and the passage is closed with a predetermined gap. There is no trace of the rod-shaped member, and by making the gap smaller than the grain size of sand, it becomes possible to remove only the air to the outside through the passage without removing the sand grains to the outside.

After the core is formed, the rod-shaped member is made to penetrate the passage so that the tip portion protrudes inward from the molding surface, so that the sand particles and the like adhering to the gap at the time of penetration can be removed. It is possible to remove it, and it is possible to prevent the passage from being blocked.

[0010]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a partial cross-sectional view showing a part of a shell machine 10 for molding a shell core having a boss-shaped convex portion, but an upper main mold 11, a lower main mold 12 and a right side insert. Modeling is performed using 21 and the left insert 41.

In the following description, only the right-side insert 21 will be described, and the description of the left-side insert 41 will be omitted. That is, between the upper main mold 11 and the lower main mold 12, the right-side insert 21 held by the right-side insert vice cylinder 22 and the left-side insert 41 are arranged. The molding space 1 formed by the main mold 12, the right-side insert 21 and the left-side insert 41 is filled with sand (particle size: approximately 0.3 mm to 0.4 mm) together with compressed air from the filling port 13, and the core is Molded.

The right-side insert vise cylinder 22 and the right-side insert 21 are connected via a bracket 23, and the right-side insert 21 connects between the upper main mold 11 and the lower main mold 12. It can be moved to the right from the position shown in Fig. 1. Further, as a configuration according to the present invention, an air passage 25 is provided in the bottom portion 24 of the concave portion 2 of the insert 21 that contacts the bottom portion of the convex portion of the core. Further, in the air passage 25, a rod-shaped member 26 whose end 27 is fixed to a fixed base 28 is arranged. Here, the air passage 25 and the rod-shaped member 26 constitute an air vent device.

Here, as shown in FIG. 1 and FIG. 2, when the sand is filled, the rod-shaped member 26 has a position in which its tip 27 is slightly offset from the bottom 24 of the insert 21 to the outside (offset amount). 29), and in the present embodiment, the air passage 25 consists of a small diameter portion 33 and a large diameter portion 34, and the gap between the rod-shaped member 26 and the small diameter portion 33. 30 is a gap that does not allow sand to escape.

After the sand is filled to form the core, the right-side insert vise cylinder 22 moves the right-side insert 21 to the right in FIG. Since it is fixed to the fixed base 28, the rod-shaped member 26 and the air passage 25 have a positional relationship shown in FIG. That is, the rod-shaped member 26 penetrates the air passage 25 so that the tip portion 27 is located at a position projecting inward from the bottom portion 24 of the insert 21.

Next, the operation according to this embodiment will be described. When the molding space 1 for molding the shell core is filled with sand having a particle size of about 0.3 mm to 0.4 mm through the filling port 13, air is filled together with the sand. In the printing apparatus, an air passage 25 is provided in the bottom portion 24 of the insert 21, and the air filled in the modeling space 1 is discharged to the outside. Further, when the sand is filled, the tip portion 27 of the rod-shaped member 26 has a bottom portion of the insert 21 so that the gap 30 between the rod-shaped member 26 and the small-diameter portion 33 is a gap that does not allow the sand to escape. It is fitted until it comes to a position slightly offset to the outside from 24, so that the air is removed to the outside through the gap 30, but almost no sand is discharged.

Further, at this time, since the tip portion 27 is offset from the bottom portion 24 to the outside, no trace of the rod-shaped member 26 is left on the molding surface of the core during sand filling. After the sand is filled and the core is shaped, the action of the right insert vise cylinder 22 causes the tip 27 of the rod-shaped member 26 to project into the bottom 24 of the insert 21. Since the rod-shaped member 26 penetrates the air passage 25, when the sand having a particle size of less than about 0.3 mm is filled with the sand, the gap 30 between the rod-shaped member 26 and the small-diameter portion 33 and the tip portion 27 and the small-diameter portion 27 are formed. Even if the rod 30 sticks to the gap with the portion 33 and clogs the gap 30, it becomes possible to remove the sand particles and the like attached when the rod-shaped member 26 penetrates the gap 30 and prevent the air passage 25 from being blocked. It becomes possible to do.

Further, in the present embodiment, the movement of the right insert 21 and the left insert 41 by the insert vice cylinders 22 and 42 after the molding of the core is used to use the air passages 25 and 45. Since it is designed to prevent the blockage, the structure is not particularly complicated, the manufacturing cost is not increased, and the productivity is not hindered by the cleaning work.

Further, every time the cores 21 and 41 are moved after the core is formed and the core is taken out, the air vent device is cleaned so as to prevent the air passages 25 and 45 from being blocked. Therefore, the blockage is surely prevented. Further, FIG. 4 shows another embodiment, and when the operating stroke of the insert 21 is long, the rod-like member 26 is provided with the stepped portion 49, and the stepped portion 49 and the insert 21 are separated from each other. A spring 51 is provided between them so that the stepped portion 49 is biased by the spring 51 in such a position as to hit the bracket 50. In this case, when the nest is retracted after the sand is filled and the end 27 of the rod-shaped member 26 contacts the fixed base 28 at the retracted end, the rod-shaped member 26 projects from the bottom 24 of the nest. Thus, the sand grains and the like attached to the gap 30 are removed.

[0019]

[Effect of device]

 As described above, the present invention is an air vent device provided in a mold for molding a core by filling sand with a passage for removing the air in the mold to the outside and a tip when sand filling. Even if the part is deep from the outside, it fits into the modeling surface to close the passage with a predetermined gap, and after core molding, the tip projects from the outside to the inside from the modeling surface and penetrates the passage. Since it is configured to include the rod-shaped member, it is possible to remove the sand particles and the like adhering to the gap without hindering the improvement of productivity after core molding, and thus it is possible to prevent the passage from being blocked. There is an effect that becomes.

[Brief description of drawings]

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

FIG. 2 is a sectional view of an essential part for explaining the operation of the above embodiment.

FIG. 3 is a sectional view of an essential part for explaining the operation of the above embodiment.

FIG. 4 is a cross-sectional view of a main part showing another embodiment of the present invention.

[Explanation of symbols]

 1 Molding space 11 Upper main mold 12 Lower main mold 21 Right side insert 22 Right side insert Vise cylinder 25 Air passage 26 Bar-shaped member 30 Clearance

Claims (1)

[Scope of utility model registration request] 1. An air vent device provided in a mold for filling sand with a core to form a core, and a passage for removing air in the mold to the outside, and a tip end portion from the outside during sand filling. With a rod-shaped member that fits deeply into the modeling surface and closes the passage with a predetermined gap, and after core molding, the tip portion protrudes from the outside to the inside from the modeling surface and penetrates the passage, An air vent device comprising: