JP2004105996A - Method and apparatus for making mold - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily make a mold having smooth surface, uniformity, high density and high strength in a short period of time by filling up molding sand to every corners with a momentary impact force with a hitting, even in the case that a core pattern has any shape. <P>SOLUTION: A table 10 for setting a wooden pattern 13 in a closable molding vessel 7, is arranged so as to be freely adjusted to the height and a hitting hammer 11 is arranged on the side surface of this table 10 and a pressure-reducing means 15 for reducing the pressure in the molding vessel 7. Kneaded sand Sb is charged in the wooden pattern 13 fitting the core pattern 14 in the inner part and the wooden pattern 13 is directly or indirectly hit with the hammer 11, and the kneaded sand Sb is filled up to every corners in the wooden pattern 13 with the momentary impact force of this hitting and the wooden pattern 13 and the core pattern 14 are removed from the mold to make the mold having uniformity and high density. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a molding technique for a mold, and more particularly, to a method and an apparatus capable of molding a mold having a uniform, high-density and excellent appearance by smoothly filling a molding mold with molding sand to every corner.
[0002]
[Prior art]
Conventionally, in the molding operation of a mold in casting, a mold molding die attached with a core mold is placed in a closed molding tank, and required additives are mixed into the mold molding die while depressurizing the inside of the molding tank. Molding was performed by introducing casting sand.
By the way, since the filling density was insufficient in the above-mentioned method, the tightening work was manually performed after filling. Therefore, the finished surface not only acts as an obstruction surface, but also causes variations in the packing density, resulting in insufficient overall strength and unfavorable work efficiency.
[0003]
[Problems to be solved by the invention]
The problem to be solved by the present invention is to solve these conventional problems, and it is possible to fill molding sand to every corner with instantaneous impact force due to impact, regardless of the shape of the core, and the surface is smooth. It is an object of the present invention to provide a mold molding method and a mold molding apparatus capable of easily molding a uniform, high-density, high-strength mold in a short time.
[0004]
[Means for Solving the Problems]
The configuration of the present invention that has solved such a problem includes:
1) Casting sand is poured into a mold for molding having a core mold mounted therein, and the molding mold is directly or indirectly hit with a hammer, and the molding sand is instantaneously impacted by the impact. A mold molding method in which a mold is completely filled into a mold, and the mold and the core are removed from the mold to form a uniform and high-density mold 2) The core is mounted in a closed molding tank. The molding method 3 according to 1) above, wherein the molding mold is placed and the molding sand is blown into the molding mold while the pressure in the molding tank is reduced while being blown into the molding mold to increase the filling rate of the molding sand. The method of 1) or 2), wherein the impact energy is repeatedly transmitted to the mold forming mold in a predetermined order by repeatedly striking the plurality of locations, so that the impact energy is evenly transmitted to the mold molding mold. 80 to 200 Nm in the range of 30 to 100 hits / minute 5) The molding method according to any one of the above 1) to 3), 5) a molding hammer provided on a side surface of a table on which the molding die is installed, and a striking force transmitted to the molding die through the table. Molding device 6) A plurality of hitting hammers are provided at predetermined intervals on the side surface of the table, and each of the hitting hammers is repeatedly operated in a predetermined order, so that the hitting force can be evenly transmitted to the mold making die. 7) The molding apparatus according to 5) or 6) above, wherein the impact hammer moves the hammer forward and backward by intermittent pumping of compressed air to directly hit the side surface of the table. A mixer for accommodating casting sand and a required additive is provided below the discharge port of the storage tank to obtain kneaded sand, and a mixer having an upper surface opened below the discharge port of the mixer. Provide a sealable mold tank with a shutter for opening and closing the condensed sand input port and an entrance with a mold mold door, and a table for setting the mold mold in the mold tank is provided with adjustable height. The mold molding apparatus according to any one of the above items 5) to 7), wherein a hitting hammer is provided on a side surface of the table, and pressure reducing means for reducing the pressure in the molding tank is provided.
[0005]
[Action]
According to the present invention, when casting sand is poured into a mold for molding to which a core of a required shape is attached, and the mold for molding is directly or indirectly hit, the molding sand is instantaneously impacted by the instantaneous impact force. A high-strength mold with a high filling density and a high filling density is formed in a short time. In addition, the surface can be finished smoothly due to the high density, and a high quality cast product with a beautiful surface can be manufactured. Furthermore, the mold is not collapsed during pouring due to its high strength, and the pouring can be performed smoothly because the mold surface is smooth.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
The mold for molding with the core mold of the present invention is arranged in a closed molding tank, and when the molding sand is blown into the mold for molding while being depressurized, the molding sand is charged. The rate can be increased in a short time. By repeatedly hitting a plurality of portions of the mold for molding in a predetermined order, the impact force is evenly transmitted to the mold for molding, and a more uniform mold can be molded. The impact energy is in the range of 80 to 200 N · m, and this is performed at a frequency of 30 to 100 times / min to continuously give an instantaneous impact force.
As the mold making apparatus, a configuration is used in which a striking hammer is provided on the side of the table on which the mold for forming is installed, and the striking force is indirectly transmitted to the mold for mold through the table. Preferably, a plurality of impact hammers are provided at predetermined intervals, and each impact hammer is repeatedly operated in a predetermined order to transmit the impact force evenly to the mold for mold making. As the impact hammer, a structure in which the hammer advances and retreats by intermittent pumping of compressed air to directly strike the side surface of the table is preferable because a sufficient impact force can be transmitted.
If a soundproofing damping plate is attached to the inner surface of the molding tank, the noise level can be suppressed to a low noise of 80 bB or less.
Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.
[0007]
【Example】
The embodiment shown in FIGS. 1 to 6 is an example of a mold molding apparatus of the present invention and a mold molding method for molding a desired mold using the apparatus.
FIG. 1 is an explanatory diagram of a mold making apparatus according to an embodiment.
FIG. 2 is a plan view of the striking mechanism of the embodiment.
FIG. 3 is a side view of the striking mechanism of the embodiment.
FIG. 4 is an explanatory diagram illustrating a molding process of the mold of the example.
FIG. 5 is a flowchart showing the steps of the mold making of the example.
FIG. 6 is a graph showing an impact waveform due to the impact of the example.
[0008]
In the figure, 1 is a mold making apparatus, 1a is a column, 1b is a loading table for disposing a mixer at a loading position, 2 is an original sand tank, 3 is a measuring mass, 3a is an adjusting valve for adjusting a discharge amount, 4 is a mixer, 4a is a discharge path, 5 is a storage tank, 5a is a drop hole, 5b is a break-in mechanism, 6 is a shutter, 6a is an opening / closing mechanism for opening and closing the shutter 6, 7 is a molding tank, 7a is an intake port, 7b is a loading / unloading port, 7c is a packing, 8 is a shutter, 8a is an opening / closing mechanism for opening and closing the shutter 8, 9 is an electric transport roller, 10 is a hitting mechanism, 10a is a cradle, 10b is wheels, 10c is a table, 10d is a pallet, and 10e is hitting. Receiving part, 11 is a hammer, 11a is a hammer, 11b is an air hose, 12 is a lifter, 13 is a wooden mold, 13a is an intake hole, 13b is a vent hole with a sandproof filter, 14 is a core type, 5 decompression means, Sa is Motosuna, Sb is kneaded sand.
[0009]
In the present embodiment, as shown in FIG. 1, a source sand tank 2 for storing source sand Sa is provided at an upper part of an upright support 1 a, and a supply amount of source sand Sa is adjusted at a lower end of the same sand tank 2. A weighing mass 3 is provided, and a movable mixer 4 having a discharge path 4a is arranged below the weighing mass 3 on a loading table 1b.
A storage tank 5 for temporarily storing the kneaded sand Sb kneaded by the mixer 4 is provided below the loading table 1b, and a plurality of drop holes 5a for dropping the kneaded sand Sb are formed on the bottom surface of the storage tank 5; On the side surface of the storage tank 5, there is provided a break-in mechanism 5b for breaking down and eliminating a hole formed in the sand during suction.
A shutter 6 for opening and closing the drop hole 5a is provided on the lower surface of the storage tank 5 so as to be able to advance and retreat by an opening / closing mechanism 6a, and an intake port 7a for taking in the kneaded sand Sb on the upper side and one side below the shutter 6 and a wooden mold 13; A molding tank 7 having a loading / unloading port 7b for allowing the impact mechanism 10 to enter and exit is provided. Packing 7c for improving airtightness is provided at an inner edge of the intake 7a and an outer edge of the loading / unloading port 7b. Is provided with a shutter 8 for opening and closing the loading / unloading port 7b so as to be vertically movable by an opening / closing mechanism 8a.
A plurality of electric transport rollers 9 are arranged side by side in the molding tank 7 at the same height as the lower edge of the loading / unloading port 7b, and a lifter for lifting the striking mechanism 10 and the wooden mold 13 loaded and unloaded by the transport rollers 9 in the vertical direction. 12 is provided below the molding tank 7.
The striking mechanism 10 is provided with a table 10c on a box-shaped receiving base 10a having wheels 10b for movement on the side as shown in FIGS. 2 and 3, and a core 14 and a pallet 10d on the table 10c via a pallet 10d. The wooden mold 13 is mounted in a fixed position. A plurality of intake holes 13a for taking in the kneaded sand Sb are formed on the upper surface of the wooden mold 13, and a vent hole 13b with a sandproof filter for suction is formed on each side surface.
[0010]
In the present embodiment, first, as shown in FIG. 5, a predetermined amount of raw sand Sa is charged into the mixer 4 with the measuring mass 3 and necessary additives are respectively charged into the mixer 4 in a timed manner. Is kneaded to obtain kneaded sand Sb, which is discharged and stored in the storage tank 5.
On the other hand, the core mold 14 having the same shape as the desired casting is attached to the box-shaped wooden mold 13 and assembled and attached to the striking mechanism 10, the shutter 8 is opened, and the wooden mold 13 and the striking mechanism 10 are moved from the loading / unloading port 7b. It is carried into the molding tank 7 by the transport roller 9, raised by the lifter 12, and the upper surface of the wooden mold 13 having the intake hole 13 a is pressed against the packing 7 c on the inner edge of the intake port 7 a of the molding tank 7, and the shutter 8 is closed. Then, the molding tank 7 is sealed.
Next, as shown in FIG. 4A, the shutter 6 is opened, and the inside of the molding tank 7 is sucked by the pressure reducing means 15 to reduce the pressure. The kneaded sand Sb in the storage tank 5 falls from the drop hole 5a due to the negative pressure due to the suction, and the air in the wooden mold 13 is sucked from the vent hole 13b while preventing the kneaded sand Sb from being sucked. It is taken in from 13a. At this time, a hole may be formed in the kneaded sand Sb in the storage tank 5 due to the negative pressure due to suction. However, the storage tank 5 is vibrated by the break-in mechanism 5b to eliminate the hole, and the molding speed is improved.
In the process of taking in the kneaded sand Sb, as shown in FIG. 4 (b), each of the hammer 11 is sequentially operated clockwise, and the hammer 11a corresponding to about 450 g is received in the hammer receiving portion 10e of the gantry 10a for 0.4 sec. Tap directly at intervals. The instantaneous impact force of the tapping is continuously transmitted to the wooden mold 13 through the table 10c and the pallet 10d, and the mixed sand Sb being taken in spreads smoothly to every corner of the core mold 14 without being clogged on the way. Assuming that the four impact hammers 11 are clockwise (a) to (d), the impact force when each of them is continuously operated at intervals of 0.4 seconds has a waveform as shown in the graph of FIG.
When the filling is completed, the impact hammer 11 and the pressure reducing means 15 are stopped to return the inside of the molding tank 7 to atmospheric pressure, the shutter 6 is closed, and the wooden mold 13 and the impact mechanism 10 are lowered by the lifter 12. Thereafter, the shutter 8 is opened, the wooden mold 13 and the striking mechanism 10 are carried out of the molding tank 7 by the transport roller 9, and the wooden mold 13 is removed from the core mold 14 to obtain a desired mold. Then, these steps are repeated according to the flow chart shown in FIG. 5 to continuously produce the mold.
[0011]
In the present embodiment, since it is configured as described above, a core mold of a required shape is attached in the mold for mold making, casting sand is poured into the mold for mold make, and the mold for mold is directly or indirectly hit. By doing so, the molding sand spreads to every corner of the core mold by the instantaneous impact force, and a high-strength mold having a packing density of 95% or more can be formed in a short time. In addition, the surface can be finished smoothly due to the high density, and a high quality cast product with a beautiful surface can be manufactured. In addition, the mold does not collapse during pouring due to its high strength, and the pouring is performed smoothly because the inner surface of the mold is smooth.
[0012]
FIG. 7 shows an example in which a hitting hammer that gives an upward impact to the lifter of the mold making apparatus of the embodiment is provided.
FIG. 7 is an explanatory diagram of a mold making apparatus according to another example of the embodiment.
In another example of the embodiment, as shown in FIG. 7, two hitting hammers 11 are attached to the lower surface of the lifter 12 at predetermined intervals, and the upward hitting can be transmitted to the wooden mold 13 through the receiving base 10 a of the hitting mechanism 10. Like that. Therefore, compared with the embodiment, the kneaded sand Sb spreads more smoothly and evenly to every corner of the core mold 14, and can sufficiently cope with the core mold 14 having a complicated shape.
In addition, reference numerals and configurations are the same as those of the mold making apparatus of the embodiment.
[0013]
【The invention's effect】
As described above, according to the present invention, the casting mold sand can be filled to every corner with an instantaneous impact force by hitting, regardless of the shape of the core mold, and the surface has a smooth, uniform, high-density, high-strength mold. Can be easily provided in a short time.
[Brief description of the drawings]
FIG. 1 is an explanatory view of a mold making apparatus according to an embodiment.
FIG. 2 is a plan view of the striking mechanism of the embodiment.
FIG. 3 is a side view of the striking mechanism of the embodiment.
FIG. 4 is an explanatory view showing a molding process of a mold according to an example.
FIG. 5 is a flow chart showing a mold forming process of an example.
FIG. 6 is a graph showing an impact waveform due to impact in the example.
FIG. 7 is an explanatory view of a mold making apparatus according to another example of the embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Mold molding apparatus 1a Column 1b Input stand 2 Original sand tank 3 Measuring mass 3a Adjustment valve 4 Mixer 4a Discharge path 5 Storage tank 5a Drop hole 5b Break-in mechanism 6 Shutter 6a Opening / closing mechanism 7 Molding tank 7a Inlet 7b Loading / unloading port 7c Packing Reference Signs List 8 shutter 8a opening / closing mechanism 9 transport roller 10 hitting mechanism 10a receiving stand 10b axle 10c table 10d pallet 10e hitting receiving section 11 hitting hammer 11a hammer 11b air hose 12 lifter 13 wooden mold 13a intake hole 13b vent hole 14 core mold 15 decompression means Sa original sand Sb kneading sand

Claims (8)

Casting sand is poured into a mold for molding with a core mold attached inside, and the mold for molding is directly or indirectly hit with a hitting hammer, and the molding sand is molded with instantaneous impact force by the impact. A mold molding method in which a mold is filled to every corner, and a mold and a core mold are removed from the mold to produce a uniform and high-density mold. Placing a mold mold with a core mold attached in a closed mold tank, and hitting while casting molding sand into the mold mold while depressurizing the inside of the mold tank, increasing the filling rate of molding sand The method according to claim 1, wherein 3. The mold molding method according to claim 1, wherein a plurality of locations of the mold are repeatedly hit in a predetermined order, so that the impact force is evenly transmitted to the mold. The method according to any one of claims 1 to 3, wherein the impact is performed in a range of 80 to 200 Nm at a frequency of 30 to 100 times / min. A mold molding apparatus in which a striking hammer is provided on a side surface of a table on which a mold is placed, so that a striking force can be transmitted to the mold through the table. 6. The mold molding according to claim 5, wherein a plurality of impact hammers are provided at predetermined intervals on the side surface of the table, and the operation of each impact hammer is repeated in a predetermined order so that the impact force can be evenly transmitted to the mold molding die. apparatus. The mold making apparatus according to claim 5 or 6, wherein the impact hammer has a structure in which the hammer is moved forward and backward by intermittent pressure feeding of compressed air to directly strike a side surface of the table. A mixing tank is provided for containing molding sand, a mixer is provided below the discharge port of the storage tank to mix the molding sand and a required additive to obtain kneaded sand, and a kneading sand having an upper surface opened below the discharge port of the mixer. Provide a sealable molding tank with a shutter for opening and closing the input port and an entrance with a mold molding mold door, and a table for installing the mold molding mold in the molding tank is provided with a height adjustable, The mold molding apparatus according to any one of claims 5 to 7, further comprising: a hammer provided on a side surface;

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