U.S. patent application number 15/527183 was filed with the patent office on 2017-11-16 for automatic pouring machine and method for automtically pouring that have ability to pressurize.
This patent application is currently assigned to SINTOKOGIO, LTD.. The applicant listed for this patent is FUJIWA DENKI CO., LTD., SINTOKOGIO, LTD.. Invention is credited to Koichi BANNO, Masayuki KATO, Tadashi NISHIDA.
Application Number | 20170326636 15/527183 |
Document ID | / |
Family ID | 56073778 |
Filed Date | 2017-11-16 |
United States Patent
Application |
20170326636 |
Kind Code |
A1 |
NISHIDA; Tadashi ; et
al. |
November 16, 2017 |
AUTOMATIC POURING MACHINE AND METHOD FOR AUTOMTICALLY POURING THAT
HAVE ABILITY TO PRESSURIZE
Abstract
To provide a machine and method for efficiently pouring and
definitely filling only a desired cavity with molten metal to cause
the molten metal to solidify there. The automatic pouring machine
(1) that has an ability to pressurize having a ladle (2) for
pouring molten metal into a mold (A) comprises a pouring unit (10)
that can move a ladle in the direction parallel to, and in the
direction perpendicular to, a line (L) of molds where a plurality
of molds are transported and a unit (20) for pressurizing the
molten metal that is supported by the pouring unit and that
supplies pressurized gas and a granular material to the mold into
which molten metal has been poured. The unit (20) supplies the
pressurized gas and the granular material to the mold that is next
to the mold into which the pouring unit pours molten metal.
Inventors: |
NISHIDA; Tadashi; (Aichi,
JP) ; KATO; Masayuki; (Aichi, JP) ; BANNO;
Koichi; (Aichi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SINTOKOGIO, LTD.
FUJIWA DENKI CO., LTD. |
Aichi
Aichi |
|
JP
JP |
|
|
Assignee: |
SINTOKOGIO, LTD.
Aichi
JP
FUJIWA DENKI CO., LTD.
Aichi
JP
|
Family ID: |
56073778 |
Appl. No.: |
15/527183 |
Filed: |
November 26, 2014 |
PCT Filed: |
November 26, 2014 |
PCT NO: |
PCT/JP2014/081199 |
371 Date: |
May 16, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B22D 18/04 20130101;
B22D 39/026 20130101; B22D 27/09 20130101; B22D 27/13 20130101;
B22D 39/02 20130101 |
International
Class: |
B22D 39/02 20060101
B22D039/02; B22D 27/13 20060101 B22D027/13; B22D 18/04 20060101
B22D018/04 |
Claims
1. An automatic pouring machine that has an ability to pressurize
comprising: a pouring unit that has a ladle for pouring molten
metal into a mold and that can be transported along a line of molds
where a plurality of molds are transported; and a unit for
pressurizing the molten metal that is supported by the pouring unit
and that supplies pressurized gas and a granular material to the
mold into which molten metal has been poured from the pouring unit;
wherein the unit for pressurizing the molten metal has a hopper
that stores the granular material, a mouth that hermetically
connects with a sprue of the mold that is filled with the molten
metal and which mouth feeds the pressurized gas and the granular
material to the mold, a regulating chamber that regulates an amount
of the granular material to be supplied from the hopper to the
mouth, a piping that introduces the pressurized gas to the
regulating chamber, and a piping that connects with the mouth to
introduce the pressurized gas; and wherein the unit for
pressurizing the molten metal supplies the pressurized gas and the
granular material to the mold among the plurality of molds that are
located next to the mold into which the pouring unit pours the
molten metal.
2. The automatic pouring machine that has the ability to pressurize
of claim 1, wherein the unit for pressurizing the molten metal is
configured to move the mouth in the direction that is parallel to,
and in the direction that is perpendicular to, the line of molds
where a plurality of molds are transported.
3. The automatic pouring machine that has the ability to pressurize
of claim 2, further comprising a position sensor that detects a
position of the sprue of the mold so as to move the mouth to the
position of the sprue.
4. The automatic pouring machine that has the ability to pressurize
of claim 1, wherein the pouring unit has a traversing carriage that
moves parallel to the line of molds and a carriage for moving back
and forth that moves perpendicularly to the line of molds on the
traversing carriage, and wherein the unit for pressurizing the
molten metal is supported by the traversing carriage.
5. The automatic pouring machine that has the ability to pressurize
of any of claims 1 to 4, wherein the granular material is dry
silica sand.
6. A method for automatically pouring that has an ability to
pressurize, wherein molten metal is poured from a ladle that is
transported along a line of molds where a plurality of molds are
transported, and wherein pressurized gas and a predetermined amount
of a granular material are supplied from a unit for pressurizing
the molten metal to the mold that is filled with the molten metal,
wherein the unit for pressurizing the molten metal has a hopper
that stores the granular material, a mouth that hermetically
connects with the sprue of the mold that is filled with the molten
metal and which mouth feeds the pressurized gas and the granular
material to the mold, a regulating chamber that regulates an amount
of the granular material to be supplied from the hopper to the
mouth, a first piping that introduces the pressurized gas to the
regulating chamber, and a second piping that connects with the
mouth to introduce the pressurized gas, and wherein the unit for
pressurizing the molten metal is configured to move along the line
of molds together with the ladle, the method comprising the steps
of: moving the ladle so that molten metal can be poured into the
sprue of a first mold on the line of molds where a plurality of
molds are transported; pouring molten metal from the ladle to the
first mold; hermetically connecting the mouth to the sprue of a
second mold that is located next to the first mold and that is
filled with molten metal; supplying pressurized gas from the second
piping to the second mold through the mouth; regulating a
predetermined amount of the granular material by the regulating
chamber, which granular material has been stored in the hopper; and
supplying the regulated granular material to the second mold
through the mouth by supplying the pressurized gas from the first
piping to the regulating chamber.
7. The method for automatically pouring that has the ability to
pressurize of claim 6 further comprising the steps of: detecting a
position of the sprue of the second mold by means of a position
sensor; and moving the mouth based on the detected position.
8. The method for automatically pouring that has the ability to
pressurize of claim 6, wherein a time when pouring molten metal
into the first mold is completed coincides with a time when
supplying the pressurized gas and the granular material to the
second mold is completed, and wherein the times coincide with a
time when the plurality of molds on the line of molds start to be
transported.
9. The method for automatically pouring that has the ability to
pressurize of claim 6, wherein, if a position of the sprue of the
first mold is changed from a position of the sprue of the second
mold, the ladle is moved so as to pour molten metal into the sprue
of the first mold, and then in the unit for pressurizing the molten
metal that has been moved together with the ladle the mouth is
moved so as to be hermetically connected with the sprue of the
second mold.
10. The method for automatically pouring that has the ability to
pressurize of any of claims 6 to 9, wherein the granular material
is dry silica sand.
Description
TECHNICAL FIELD
[0001] The present invention relates to a pouring machine and a
method for pouring that are used in a foundry. Specifically, it
relates to a pouring machine and method that have the ability to
pressurize molten metal in a mold.
BACKGROUND ART
[0002] In a foundry, molten metal that has melted in a melting
furnace and that is at a high temperature is poured into a mold in
an area for pouring, to thereby cast a product. When molten metal
is poured into a mold, it is poured into the upper end of a pouring
cup in consideration of shrinkage during solidification in the
mold. After cooling the mold, the mold is shaken out. Then the
sprue, the runner, and the riser, which are some of the parts other
than the product, are separated from the product so as to be again
melted, for return scrap. Among these parts, though the riser is
needed during solidification to ensure the soundness of the
product, the runner and the sprue are needed only for filling
molten metal into a cavity during pouring.
[0003] Conventionally, a casting method has been proposed to fill
molten metal only into a desired cavity among the cavities and to
solidify it. For example, by a method disclosed in Japanese Patent
No. 4150764 pressurized gas is supplied through the sprue to fill
molten metal into a desired cavity to cause it to solidify there.
Thus the pressure of the gas needs to be maintained until the
molten metal solidifies. Further, since the molten metal is
confined there by means of pressurized gas, the time to solidify is
long and inefficient. By the method disclosed in Japanese Patent
Laid-open Publication No. 2010-269345, after pouring molten metal
at the same volume as that of a desired cavity, the filling
material is supplied to the cavity through the sprue before the
cavity is filled with the molten metal, so that the cavities other
than the desired cavity are filled with the filling material.
However, depending on the arrangement of the cavities or the shapes
of the runner and the sprue, heat is transferred to the filling
material so that the temperature on the surface of the molten metal
becomes low. Then the molten metal may solidify before the desired
cavity is filled with it. The resistance to feed the filling
material to the cavities may increase. Thus, there are some cases
where a desired filling of the molten metal is difficult.
[0004] The present invention aims to provide a machine and method
for efficiently pouring and definitely filling only a desired
cavity with molten metal among cavities to cause the molten metal
to solidify there.
DISCLOSURE OF INVENTION
[0005] An automatic pouring machine 1 that has an ability to
pressurize of the present invention comprises, for example, as in
FIGS. 1, 2, 5, and 6, a pouring unit 10 that has a ladle 2 for
pouring molten metal into a mold A and that can be transported
along a line L of molds where a plurality of molds A are
transported. It also comprises a unit 20 for pressurizing the
molten metal that is supported by the pouring unit 10 and that
supplies pressurized gas and a granular material to the mold A into
which molten metal has been poured from the pouring unit 10. The
unit 20 for pressurizing the molten metal has a hopper 22 that
stores the granular material and a mouth 26 that connects with a
sprue A1 of the mold A that is filled with the molten metal, which
mouth 26 feeds the pressurized gas and the granular material to the
mold A. It also has a regulating chamber 24 that regulates an
amount of the granular material to be supplied from the hopper 22
to the mouth 26. It also has a piping 28 that introduces the
pressurized gas to the regulating chamber 24 and a piping 30 that
connects with the mouth 26 to introduce the pressurized gas. The
unit 20 for pressurizing the molten metal supplies the pressurized
gas and the granular material to the mold A(2) among the plurality
of molds A that is located next to the mold A(1) into which the
pouring unit 10 pours the molten metal. Incidentally, the molds A
are individually indicated by a number in parentheses, such as
A(1), A(2), . . . (see FIG. 6).
[0006] By the above configuration, pressurized gas and a granular
material are supplied from the unit for pressurizing the molten
metal to a mold into which molten metal has been poured from the
pouring unit. Since the pressurized gas is supplied, the molten
metal is squeezed into the desired cavity. Since the predetermined
amount of the granular material is supplied, the molten metal that
has been squeezed into the cavity is plugged. Then heat is
transferred to the granular material so that the molten metal at
the entrance to the cavity is cooled and solidifies. Thus the
automatic pouring machine can efficiently pour molten metal into a
mold and definitely fill only a desired cavity among cavities with
molten metal so that the molten metal solidifies there. Since the
unit for pressurizing the molten metal supplies the pressurized gas
and the granular material to the mold that is located next to the
mold among the plurality of molds that is poured by the pouring
unit, the unit for pressurizing the molten metal can supply the
pressurized gas and the granular material immediately after the
pouring unit pours the molten metal into the mold.
[0007] In the above-mentioned automatic pouring machine 1 that has
the ability to pressurize, for example, as in FIG. 4, the unit 20
for pressurizing the molten metal may be configured to move the
mouth 26 in the direction that is parallel to, and in the direction
that is perpendicular to, the line L of molds where a plurality of
molds A are transported. By the above configuration, if the pouring
unit moves to be aligned with a new position of the sprue when the
position of the sprue is changed, quickly and easily the mouth can
be hermetically connected with the sprue of the mold.
[0008] The above-mentioned automatic pouring machine 1 that has the
ability to pressurize, for example, as in FIG. 2, further comprises
a position sensor 50 that detects a position of the sprue A1 of the
mold A so as to move the mouth 26 to the position of the sprue A1.
By the above configuration, since the position of the sprue is
detected by means of the position sensor to move the unit for
pressurizing the molten metal, the mouth can be rapidly and easily
moved to the position of the sprue of the mold to be hermetically
connected with it.
[0009] In the above-mentioned automatic pouring machine 1 that has
the ability to pressurize, for example, as in FIGS. 1 and 2, the
pouring unit 10 may have a traversing carriage 4 that moves
parallel to the line L of molds. It also has a carriage for moving
back and forth 6 that moves perpendicularly to the line L of molds
on the traversing carriage 4. The unit 20 for pressurizing the
molten metal may be supported by the traversing carriage 4. By the
above configuration, since the distance between the position for
pouring and the position of the mouth is maintained to be equal to
the length of a mold when the position to pour molten metal from
the ladle into the mold changes along the line of molds, pouring by
the pouring unit and supplying the pressurized gas and the granular
material by the unit for pressurizing the molten metal can be
simultaneously carried out. Further, when a long time is needed for
pouring, the molds are transported while the pouring continues.
Even in this case, supplying the pressurized gas and the granular
material can be continued because the unit for pressurizing the
molten metal moves together with the pouring unit.
[0010] In the above-mentioned automatic pouring machine 1 that has
the ability to pressurize, the granular material may be dry silica
sand. It has a high fluidity, and so is supplied to a mold so that
the runner hardly clogs with it. Further, it hardly deteriorates
even when contacting hot molten metal. It is cheap and easy to
obtain. Thus the automatic pouring machine is easy to use.
[0011] In a method for automatically pouring that has an ability to
pressurize of the present invention, for example, as in FIGS. 1, 2,
5, and 6, molten metal is poured from a ladle 2 that is transported
along a line of molds where a plurality of molds A are transported,
and pressurized gas and a predetermined amount of a granular
material are supplied from a unit 20 for pressurizing the molten
metal to the mold A that is filled with the molten metal. The unit
20 has a hopper 22 that stores the granular material. It also has a
mouth 26 that hermetically connects with the sprue A1 of the mold A
that is filled with the molten metal and which mouth feeds the
pressurized gas and the granular material to the mold A. It also
has a regulating chamber 24 that regulates an amount of the
granular material to be supplied from the hopper 22 to the mouth
26. It also has a first piping 28 that introduces the pressurized
gas to the regulating chamber 24 and a second piping 30 that
connects with the mouth 26 to introduce the pressurized gas. It is
configured to move along the line L of molds together with the
ladle 2. The method comprises a step of moving the ladle 2 so that
molten metal can be poured into the sprue A1 of a first mold A(1)
on the line L of molds where a plurality of molds A are
transported. It also comprises a step of pouring molten metal from
the ladle 2 to the first mold A(1). It also comprises a step of
hermetically connecting the mouth 26 to the sprue A1 of a second
mold A(2) that is located next to the first mold A(1) and that is
filled with molten metal. It also comprises a step of supplying
pressurized gas from the second piping 30 to the second mold A(2)
through the mouth 26. It also comprises a step of regulating a
predetermined amount of the granular material by the regulating
chamber 24, which granular material has been stored in the hopper
22. It also comprises a step of supplying the regulated granular
material to the second mold A(2) through the mouth 26 by supplying
the pressurized gas from the first piping 28 to the regulating
chamber 24.
[0012] By the above configuration, the pressurized gas and the
predetermined amount of the granular material are supplied from the
unit for pressurizing the molten metal to a mold into which molten
metal has been poured from a ladle. Since the pressurized gas is
supplied to the mold, the molten metal is squeezed into a desired
cavity. Since the predetermined amount of the granular material is
supplied to the mold, the molten metal that has been squeezed into
the cavity is plugged. Since the heat is transferred to the
granular material, the molten metal at the entrance to the cavity
is cooled, and it solidifies. Thus the method for automatically
pouring can efficiently pour molten metal into a mold and
definitely fill only the desired cavity, among the cavities, with
molten metal so that the molten metal solidifies there.
[0013] The above-mentioned method for automatically pouring that
has the ability to pressurize, for example, as in FIG. 2, may
further comprise a step of detecting a position of the sprue A1 of
the second mold A(2) by means of a position sensor 50 and a step of
moving the mouth 26 based on the detected position. By the above
configuration, the mouth is quickly and accurately moved to the
position of the sprue of the mold based on the detected position by
the sensor, to be hermetically connected to the sprue.
[0014] In the above-mentioned method for automatically pouring that
has the ability to pressurize, a time when pouring molten metal
into the first mold A(1) is completed may coincide with a time when
supplying the pressurized gas and the granular material to the
second mold A(2) is completed. Further, the times may coincide with
a time when the plurality of molds A on the line L of molds start
to be transported. By the above configuration, immediately after a
mold into which molten metal was just poured from a ladle is
transported, the pressurized gas and the granular material can be
supplied from the unit for pressurizing the molten metal. Thus the
molten metal in the mold is squeezed into the desired cavity before
it solidifies. Thus the method for automatically pouring enables
only the desired cavity to be definitely filled with the molten
metal, so that the molten metal solidifies there.
[0015] In the above-mentioned method for automatically pouring that
has the ability to pressurize, if a position of the sprue A1 of the
first mold A(1) is changed from a position of the sprue A1 of the
second mold A(2), the ladle 2 may be moved so as to pour molten
metal into the sprue A1 of the first mold A(1). Then in the unit 20
for pressurizing the molten metal that has been moved together with
the ladle 2 the mouth 26 may be moved so as to be hermetically
connected with the sprue A1 of the second mold A(2). By the above
configuration even when the pouring unit is moved so that molten
metal can be poured from the ladle into the sprue, the distance
between the pouring unit and the unit for pressurizing the molten
metal is maintained to be equal to the length of a mold. Then, if
needed, the mouth may be moved to the position of the sprue. Thus
the movement of the mouth can be suppressed to be small and the
mouth can be quickly moved to the position of the sprue.
[0016] In the above-mentioned method for automatically pouring that
has the ability to pressurize, the granular material may be dry
silica sand. If so, it has a high fluidity, and so is supplied to a
mold so that the runner hardly clogs with it. Further, it hardly
deteriorates even when contacting hot molten metal. It is cheap and
easy to obtain. Thus the method for automatically pouring is easy
to use.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 shows a plan view of the automatic pouring machine
that has the ability to pressurize, as an embodiment of the present
invention.
[0018] FIG. 2 shows a front view of the automatic pouring machine
that has the ability to pressurize, as an embodiment of the present
invention.
[0019] FIG. 3 shows a plan view of an embodiment of the unit for
pressurizing the molten metal.
[0020] FIG. 4 shows a side view of an embodiment of the unit for
pressurizing the molten metal.
[0021] FIG. 5 shows a diagram of a system for pressurization of an
embodiment of the unit for pressurizing the molten metal.
[0022] FIG. 6 shows a plan view of an embodiment of the automatic
pouring machine that has the ability to pressurize at the step of
pouring.
[0023] FIG. 7 shows a side view of an embodiment of the automatic
pouring machine that has the ability to pressurize at the step of
pressurizing.
[0024] FIG. 8 shows a side view of an embodiment of the automatic
pouring machine that has the ability to pressurize that has
returned to the original position after pressurizing.
MODE FOR CARRYING OUT THE INVENTION
[0025] Below, an automatic pouring machine equipped with a unit for
pressurizing the molten metal, which machine is an embodiment of
the present invention, is discussed with reference to the drawings.
FIG. 1 shows a plan view of the automatic pouring machine 1, which
is an embodiment of the present invention. It is equipped with the
unit 20 for pressurizing the molten metal. As in FIG. 1, the
automatic pouring machine 1 is configured to move on a rail B that
is disposed to be parallel to the line L of molds on which the
molds are transported.
[0026] FIG. 2 is a front schematic view of the automatic pouring
machine 1 as in FIG. 1. As in FIG. 2, a traversing carriage 4 is
placed on the rail B so that it runs on it. The rail B is placed on
the floor. A carriage for moving back and forth 6 is placed on the
traversing carriage 4 so as to move perpendicularly to the rail B.
Specifically, a rail (not shown) is placed on the upper plane of
the traversing carriage 4 in the direction that is perpendicular to
the rail B. The carriage for moving back and forth 6 runs on that
rail. A device 8 for vertically moving the ladle is disposed on the
carriage for moving hack and forth 6. The device 8 for vertically
moving the ladle 2 moves a device 3 for tilting the ladle. The
device 3 for tilting the ladle tilts the ladle 2 that stores molten
metal. Thus, the ladle 2 can be moved in three dimensions. The
device 3 for tilting the ladle tilts the ladle 2 so as to pour the
molten metal in the ladle 2 into the mold A.
[0027] The unit 20 for pressurizing the molten metal is disposed on
the traversing carriage 4 of the automatic pouring machine 1. On
the traversing carriage 4, the unit 20 for pressurizing the molten
metal is located at a position so as to supply pressurized gas or a
granular material to a mold A(2) on the line L of molds that is
located downstream of, and next to, a mold A(1) into which molten
metal is poured from the ladle 2 by means of the automatic pouring
machine 1. By disposing the unit 20 for pressurizing the molten
metal on the traversing carriage 4 as discussed above, the unit 20
for pressurizing the molten metal can be easily installed in an
existing pouring machine. Further, it does not interrupt the
movement of the pouring unit 10.
[0028] FIG. 3 is a plan view that shows only the unit 20 for
pressurizing the molten metal in the automatic pouring machine 1
that is disposed along the line L of molds. FIG. 4 is a schematic
side view of the automatic pouring machine 1, which is seen from
the side of the unit 20 for pressurizing the molten metal. In the
unit 20 for pressurizing the molten metal, a supporting structure
12 is disposed on the traversing carriage 4. The upper part of the
supporting structure 12 is structured by beams. Each of them has an
axial direction that is perpendicular to the line L of molds. On
the supporting structure 12, a device 14 for moving the unit for
pressurizing the molten metal back and forth is provided so as to
move in the direction that is perpendicular to the line L of molds.
On the device 14, a device 16 for traversing the unit for
pressurizing the molten metal is provided so as to move in parallel
to the line L of molds. On the device 16, a device 18 for
vertically moving the unit for pressurizing the molten metal is
provided.
[0029] The devices for supplying the pressurized gas and the
granular material from the unit 20 for pressurizing the molten
metal to the mold A are supported by the device 18 for vertically
moving the unit for pressurizing the molten metal so as to move in
three dimensions. The unit 20 for pressurizing the molten metal has
a hopper 22 that stores the granular material. It also has a mouth
26 that is hermetically connected to the sprue A1 of the mold A
into which the molten metal has been poured, so as to feed the
pressurized gas and the granular material to the mold A. It also
has a piping 44 that connects the hopper 22 with the mouth 26.
Further, as in FIG. 5, the unit 20 for pressurizing the molten
metal has on the piping 44 a regulating chamber 24 that regulates
the amount of the granular material to be supplied from the hopper
22 to the mouth 26, and a first ball valve 32 and a second ball
valve 34 that act as on-off valves. Further, it has a second piping
30 that is connected to the mouth 26 to introduce the pressurized
gas. It also has a first piping 28 that introduces the pressurized
gas into the regulating chamber 24. The first piping 28 is equipped
with a first on-off valve 36 that starts and stops the supply of
the pressurized gas to the regulating chamber 24. The second piping
30 is equipped with a second on-off valve 38 that starts and stops
the supply of the pressurized gas to the mouth 26. The second
piping 30 is also equipped with a flow control valve 40 that
controls the flow of the pressurized gas to be supplied. The mouth
26 is equipped with a pressure sensor 42 that measures the pressure
of the pressurized gas so as to supply the pressurized gas to the
mold A. The hopper 22, the piping 44, the regulating chamber 24,
and the mouth 26 constitute the pressurizing device 46 that
supplies the pressurized gas and the pressurized granular material
to the mold A. Incidentally, the wording "the second piping 30 is
connected to the mouth 26 to introduce the pressurized gas" means
not only the case where the second piping 30 is directly connected
to the mouth 26, but also the case where the second piping 30 is
connected to the piping 44 to be indirectly connected to the mouth
26.
[0030] As in FIG. 4, the unit 20 for pressurizing the molten metal
has also a member 48 for constraining the mold, which member
constrains the mold A not to misalign while the pressurized gas or
the granular material is supplied by the unit 20 for pressurizing
the molten metal. The member 48 for constraining the mold has an
air cylinder, and a constraining plate (not shown) that is attached
to the air cylinder. It presses the mold A by means of the
constraining plate to fix the mold A during the operation of the
unit 20 for pressurizing the molten metal. Since the mold A is not
misaligned, the mouth 26 is facilitated to be hermetically
connected with the sprue A1. Incidentally, besides an air cylinder,
the constraining plate may be pressed by any other known means.
[0031] Any of the traversing carriage 4, the carriage for moving
back and forth 6, the device 8 for vertically moving the ladle, the
device 14 for moving the unit for pressurizing the molten metal
back and forth, the device 16 for traversing the unit for
pressurizing the molten metal, and the device 18 for vertically
moving the unit for pressurizing the molten metal, is preferably
moved by a servomotor, since it can thus be definitely moved to an
accurate position. However, any known means other than a servomotor
may be used to move any of them.
[0032] Next, with reference to FIGS. 6, 7, and 8, the operation of
the automatic pouring machine 1, which has the above-mentioned
configuration, is discussed. A plurality of molds A line up on the
line L of molds. The ladle 2 of the pouring unit 10 is filled with
molten metal that is poured from a melting furnace, and so on.
First, the filled ladle 2 is moved by means of the traversing
carriage 4 and the carriage for moving back and forth 6 to a
horizontal position to pour the molten metal into the mold A on the
line L of molds. After molten metal is once poured from the ladle 2
into the mold A, it can be poured into the sprue A1 of any mold A
that has the sprue A1 at the same position, without moving the
ladle 2, by means of the traversing carriage 4 or the carriage for
moving back and forth 6. When pouring the molten metal into a mold
A that has the sprue A1 at the same position, pouring molten metal
starts at a predetermined time after the mold A is transported on
the line L of molds by a distance that is equal to the length of
the mold A. The predetermined time may be 0 sec. When the position
of the sprue A1 changes, the ladle 2 is moved by means of the
traversing carriage 4 and the carriage for moving back and forth 6
to the position for pouring molten metal, based on the position of
the sprue Al that is detected by the position sensor 50. If the
direction to pour molten metal changes because of any deterioration
of the nozzle of the ladle 2 for pouring molten metal, the ladle 2
is moved by means of the traversing carriage 4 and the carriage for
moving back and forth 6, even when no position of the sprue A1
changes, so as to accurately pour molten metal into the sprue
A1.
[0033] The ladle 2 is elevated by means of the device 8 for
vertically moving the ladle and tilted by means of the device 3 for
tilting the ladle to start pouring molten metal into the sprue A1
of an empty mold A. The amount of molten metal that has been poured
is measured by a device for weighing, which is not shown. When a
predetermined amount of molten metal has been measured and then
poured, the pouring operation is completed. Incidentally, to
increase the accuracy of the amount to be poured, the flow of
molten metal is preferably decreased before the predetermined
amount of molten metal has been poured (the tilting angle is
gradually decreased) so that the pouring operation is stopped just
when the predetermined amount has been poured. Incidentally, the
predetermined amount of molten metal is an amount of molten metal
that is required to cast a product, i.e., a product that is cast by
the mold A. It is an amount of molten metal that is equal to the
volume of a desired cavity plus the volume that will be caused by
shrinkage plus an allowance. When the predetermined amount of
molten metal has been poured, a part of the molten metal may remain
in the runner so that a space exists in an upper part of the
desired cavity.
[0034] At the same time the molten metal is poured into the empty
ladle A, by the unit 20 for pressurizing the molten metal the
pressurized gas and the granular material are supplied to the mold
A(2) into which the molten metal has been poured. The position of
the mold A(2) is detected by means of the position sensor 50. The
mouth 26 is moved to a position right above the sprue A1 by means
of the device 14 for moving the unit for pressurizing the molten
metal back and forth and the device 16 for traversing the unit for
pressurizing the molten metal. After the pressurized gas and the
granular material are once supplied, it can be supplied to the
sprue A1 of any mold A that has the sprue A1 at the same position,
without moving the mouth 26 by means of the device 14 for moving
the unit for pressurizing the molten metal back and forth or by
means of the device 16 for traversing the unit for pressurizing the
molten metal. When supplying the pressurized gas and the granular
material to the mold A that has the sprue A1 at the same position,
supplying them starts at a predetermined time after a mold A is
transported on the line L of molds by the distance that is equal to
the length of the mold A. The predetermined time may be 0 sec. When
the position of the sprue A1 changes, the mouth 26 is moved again
to a position right above the sprue A1. In this case, to align the
position of the ladle 2 of the pouring unit 10, which position is
upstream of the unit 20 for pressurizing the molten metal, with the
position of the sprue A1, the traversing carriage 4 and the
carriage for moving back and forth 6 may move. Thus the unit 20 for
pressurizing the molten metal may move before supplying the
pressurized gas and the granular material to the mold A that has
the sprue A1 at the same position. Since the position of the sprue
is detected by means of the position sensor 50, the position of the
mouth 26 can be quickly and accurately aligned with the position of
the sprue A1. If the position of the ladle 2 for pouring is moved
by moving the pouring unit 10, even if no position of the sprue A1
changes, the mouth 26 is moved right above the sprue Al based on
the position of the sprue A1 that is detected by the position
sensor 50.
[0035] As in FIG. 7, the pressurizing device 46, i.e., the mouth
26, is lowered by means of the device 18 for vertically moving the
unit for pressurizing the molten metal. When the force of the
device 18 for vertically moving the unit for pressurizing the
molten metal to lower the mouth 26, for example, the torque of the
servomotor, reaches a predetermined value, the lowering operation
is completed. Namely, the pressing force between the mouth 26 and
the sprue A1 is caused to be equal to the predetermined value. So,
the mouth 26 contacts the sprue A1 at an appropriate force. Thus
the mouth 26 hermetically contacts the sprue A1. Further, neither
the mold A nor the mouth 26 should be damaged. Incidentally, a load
sensor, such as a load cell, which does not measure the force of
the device 18 for vertically moving the unit for pressurizing the
molten metal to lower the mouth 26, may be used to measure the
force of the mouth 26 to press the mold A to complete the lowering
operation. The member 48 for constraining the mold lowers the
constraining plate to fix the mold A(2).
[0036] When the mouth 26 covers the sprue A1 to hermetically
connect with the sprue A1 of the mold A(2), the second on-off valve
38 is opened to supply the pressurized gas from the second piping
30 into the mold A(2) via the mouth 26. Further, the first on-off
valve 36 is opened to introduce the pressurized gas from the first
piping 28 to the regulating chamber 24. Thus the granular material
in the regulating chamber 24 is supplied to the mold A(2) via the
mouth 26. The molten metal in the mold A(2) is squeezed into the
desired cavity by means of the pressurized gas and the granular
material.
[0037] Now, a method for pressurizing the mold A by using the
pressurizing device 46 as in FIG. 5 is discussed. When the mouth 26
is to be connected with the mold A, the first bail valve 32, the
second bail valve 34, the first on-off valve 36, and the second
on-off valve 38, are all closed. When the mouth 26 has been
completely lowered, the second on-off valve 38 is opened. While the
flow control valve 40 is controlled to cause the detection by the
pressure sensor 42 to be equal to a predetermined pressure, the
pressurized gas is supplied by the second piping 30 to the mold A.
The predetermined pressure is a pressure by which molten metal is
squeezed into the cavity. This pressure is maintained for a
predetermined period of time. Thus air that remains in the upper
part of the cavity flows out of the cavity because of the
permeability of the sand mold, so that the cavity is filled with
the molten metal.
[0038] Next, a method for blowing the granular material into the
mold A is discussed. First, a predetermined amount of the granular
material is stored in the regulating chamber 24 for the granular
material. After the mouth 26 is completely lowered, the second ball
valve 34 and the first on-off valve 36 are opened to feed the
pressurized gas from the first piping 28. Since in this way the
pressurized gas and the granular material are fed, the granular
material accumulates at the end of the runner, to become a
plug.
[0039] After the predetermined period of time passes, the end part
of the molten metal, which contacts the granular material, starts
to solidify. Then the second ball valve 34, the first on-off valve
36, and the second on-off valve 38, are closed. The unit 20 for
pressurizing the molten metal is elevated so that the mouth 26 is
separated from the mold A as in FIG. 8. At the same time, the
constraining plate of the member 48 for constraining the mold is
elevated.
[0040] After the second ball valve 34 is closed, the first ball
valve 32 is opened so that the granular material in the hopper 22
is introduced into the regulating chamber 24. After a predetermined
period of time passes, the first ball valve 32 is closed so that a
predetermined amount of the granular material are stored in the
regulating chamber 24. Since the granular material is introduced
from the hopper 22 to the regulating chamber 24 over a
predetermined period of time, the predetermined amount of the
granular material is regulated. The amount of the granular material
that is stored in the regulating chamber 24. i.e., the combined
weight of them, may be measured so that the first ball valve 32 is
closed when the amount becomes equal to the predetermined amount.
The predetermined amount of the granular material is an amount of
the granular material in the runner that prevents the molten metal
that has been squeezed into the desired cavity from flowing back to
the runner.
[0041] After pouring the molten metal and supplying the pressurized
gas and the granular material are completed, the molds A on the
line L of molds are transported for the distance that is equal to
the length of the molds A. Namely, as in FIG. 6, the mold A(2),
which is located in front of the pouring unit 10, is transported to
the position in front of the unit 20 for pressurizing the molten
metal and a new and empty mold A(1) is transported to the position
in front of the pouring unit 10. In the pouring unit 10, molten
metal is poured from the ladle 2 into the empty mold A(1). In the
unit 20 for pressurizing the molten metal the pressurized gas and
the granular material are supplied to the mold A(2) into which
molten metal has just been poured by means of the pouring unit
10.
[0042] In the automatic pouring machine 1 the pressurized gas and
the granular material are preferably supplied by means of the unit
20 for pressurizing the molten metal immediately after molten metal
is poured into the mold A by means of the pouring unit 10. Before
the molten metal that has been poured into the mold A starts to
solidify, it is squeezed into the desired cavity by means of the
pressurized gas and the granular material. If supplying the
pressurized gas and the granular material by means of the unit 20
for pressurizing the molten metal takes longer than pouring molten
metal by means of the pouring unit 10, the time when pouring molten
metal into the first mold A(1) by the pouring unit 10 is completed
is controlled to coincide with the time when supplying the
pressurized gas and the granular material to the second mold A(2)
by the unit 20 is completed, and the time when the plurality of
molds A on the line L of molds start to be transported is
controlled to coincide with these times. Here the wording "the time
. . . is controlled to coincide with" includes the case where the
times do not coincide with each other because of a lag between the
devices, and the case where they do not do so as to allow for the
initiation of the operation of the respective units 10, 20 or the
operation of the line L of molds.
[0043] The pressurized gas that is used by the automatic pouring
machine 1 is typically air, but is not limited to air. The granular
material that is used by the automatic pouring machine 1 is
preferably heat-resistant granular material, such as refractory
granular material, or sand, or steel balls, but are not limited to
those items.
[0044] As discussed above, immediately after molten metal is poured
into the mold A the mouth 26 is hermetically connected with the
sprue A1 so as to pressurize the mold A by means of the pressurized
gas and to supply the granular material to it. Thus the molten
metal is squeezed into the desired cavity before it starts to
solidify.
[0045] After the cavity is filled with the molten metal the
granular material that has been put into the runner functions as a
plug. Thus the molten metal is prevented from flowing back to the
runner, etc. Thus the cavity can be quickly and definitely filled
with molten metal. Since the granular material functions as a plug,
the molten metal is prevented from flowing back. Thus a cast
product, after being shaken out, has no part that corresponds to
the runner or the sprue.
[0046] Further, the mold in which the granular material functions
as a plug is transported from the unit 20 for pressurizing the
molten metal, i.e., the automatic pouring machine 1, to cause the
molten metal to solidify. That is, the automatic pouring machine 1
can promptly handle the next mold A. Thus the efficiency is
good.
[0047] Further, the molten metal that has been poured is squeezed
into the cavity by means of the unit 20 for pressurizing the molten
metal, which unit 20 is separated from the pouring unit 10. Thus
pouring molten metal by means of the pouring unit 10 and supplying
the pressurized gas and the granular material by means of the unit
20 can be simultaneously carried out. That is, the casting
operation can be efficient.
[0048] Since pressurizing by means of the pressurized gas and
supplying the granular material is simultaneously carried out, both
the power of pressurizing and the power of supplying the granular
material are used to squeeze the molten metal into the cavity. Thus
the molten metal can be quickly and definitely squeezed into the
cavity. When pressurizing by means of the pressurized gas is
carried out before supplying the granular material, the molten
metal is prevented from being cooled by the granular material.
Thus, the molten metal is not cooled by the granular material.
Since the molten metal is prevented from solidifying because of
being cooled, it is quickly and easily squeezed into the
cavity.
[0049] In the automatic pouring machine 1 the unit 20 for
pressurizing the molten metal is located, so as to supply the
pressurized gas and the granular material to the mold A(2) that is
downstream of, and next to, the mold A(1) into which molten metal
is poured from the ladle 2 of the pouring unit 10 on the line L of
molds. Thus the unit for pressurizing the molten metal is easily
added to an existing pouring unit so that the existing one is
converted to an automatic pouring machine that has the ability to
pressurize. Further, the unit 20 for pressurizing the molten metal
supplies the pressurized gas and the granular material to the mold
A(2) that is next to the mold A(1) into which molten metal is
poured. Thus the pressurized gas and the granular material are
supplied immediately after molten metal is poured into the mold
A(2) by means of the pouring unit 10. Thus the molten metal in the
mold A(2) can be squeezed into the desired cavity before it starts
to solidify. That is, the pressure of the pressurized gas can be
low and the amount of the granular material to be supplied can be
small.
[0050] In the automatic pouring machine 1 the unit 20 for
pressurizing the molten metal is supported by the traversing
carriage 4 of the pouring unit 10. When the position of the sprue
A1 of the mold A is changed or when the nozzle of the ladle 2
deteriorates, the pouring unit 10 is moved by means of the
traversing carriage 4 and the carriage for moving back and forth 6
to align the ladle 2 with the sprue A1. Then, if needed, the device
14 for moving the unit for pressurizing the molten metal back and
forth and the device 16 for traversing the unit for pressurizing
the molten metal of the unit 20 for pressurizing the molten metal
are moved to align the mouth 26 with the sprue A1. So the distance
between the ladle 2 and the mouth 26 is maintained to be equal to
the length of a mold so that the movement of the mouth 26 can be
shortened. Thus the unit 20 for pressurizing the molten metal can
be quickly and definitely moved and continuous operations can be
conducted. Incidentally, the unit 20 for pressurizing the molten
metal may be located at a position other than on the traversing
carriage 4 of the pouring unit 10. It may also be located on a
supporting structure that is separate from the pouring unit 10.
[0051] In the above detailed description, we do not discuss the
following matters: the device 3 for tilting the ladle, the
traversing carriage 4, the carriage for moving back and forth 6,
the device 8 for vertically moving the ladle, the device 14 for
moving the unit for pressurizing the molten metal back and forth,
the device 16 for traversing the unit for pressurizing the molten
metal, the device 18 for vertically moving the unit for
pressurizing the molten metal, the member 48 for constraining the
mold, the first ball valve 32, the second ball valve 34, the first
on-off valve 36, the second on-off valve 38, the flow control valve
40, and so on, may be automatically operated. Alternatively, they
may be operated by means of a controller (not shown) based on the
input by a user.
[0052] In the above discussion the mouth 26 is moved, by means of
the device 14 for moving the unit for pressurizing the molten metal
back and forth and by means of the device 16 for traversing the
unit for pressurizing the molten metal. It may be moved by having a
part of the piping 44 be flexible. The part of the piping 44 may be
downstream of the second ball valve 34. In this case, if the mouth
26 is largely moved by means of the flexibility of the piping 44,
the curvature of the piping 44 becomes large, so that the granular
material can hardly pass through it. Thus even though the piping 44
is flexible, the device 14 for moving the unit for pressurizing the
molten metal back and forth and the device 16 for traversing the
unit for pressurizing the molten metal are preferably provided.
[0053] The present invention is not limited to any specific
embodiment to carry out the invention. Various possible changes and
modifications will be apparent to those of ordinary skill in the
art that are within the scope of the technical ideas that are
defined in the claims.
[0054] Below, the main reference numerals and symbols that are used
in the detailed description and drawings are listed. [0055] A. the
mold [0056] A1. the sprue [0057] B. the rail [0058] L. the line of
molds [0059] 1. the automatic pouring machine [0060] 2. the ladle
[0061] 3. the device for tilting the ladle [0062] 4. the traversing
carriage [0063] 6. the carriage for moving back and forth [0064] 8.
the device for vertically moving the ladle [0065] 10. the pouring
unit [0066] 12. the supporting structure [0067] 14. the device for
moving the unit for pressurizing the molten metal back and forth
[0068] 16. the device for traversing the unit for pressurizing the
molten metal [0069] 18. the device for vertically moving the unit
for pressurizing the molten metal [0070] 20. the unit for
pressurizing the molten metal [0071] 22. the hopper [0072] 24. the
regulating chamber [0073] 26. the mouth [0074] 28. the first piping
[0075] 30. the second piping [0076] 32. the first ball valve [0077]
34. the second ball valve [0078] 36. the first on-off valve [0079]
38. the second on-off valve [0080] 40. the flow control valve
[0081] 42. the pressure sensor [0082] 44. the piping [0083] 46. the
pressurizing device [0084] 48. the member for constraining the mold
[0085] 50. the position sensor
* * * * *