U.S. patent application number 16/634478 was filed with the patent office on 2021-07-08 for casting mold and manufacturing method of cast part.
The applicant listed for this patent is Marelli Corporation. Invention is credited to Takaaki Ikari, Naohisa Kamiyama, Ikuo Kataoka, Toshihiko Kubo, Makoto Murakami, Tetsuzo Nishimura, Shinya Sato.
Application Number | 20210205875 16/634478 |
Document ID | / |
Family ID | 1000005666479 |
Filed Date | 2021-07-08 |
United States Patent
Application |
20210205875 |
Kind Code |
A1 |
Kamiyama; Naohisa ; et
al. |
July 8, 2021 |
Casting Mold and Manufacturing Method of Cast Part
Abstract
The casting mold is provided with: the molding wall portion
forming the internal space; and the filling ports that open to the
molding wall portion and that allow the molten metal to flow into
the internal space. In this configuration the channel center lines
of the filling ports intersect the surface of the heater at the
non-perpendicular contact angle.
Inventors: |
Kamiyama; Naohisa;
(Saitama-shi, Saitama, JP) ; Kubo; Toshihiko;
(Saitama-shi, Saitama, JP) ; Nishimura; Tetsuzo;
(Ueda-shi, Nagano, JP) ; Murakami; Makoto;
(Ueda-shi, Nagano, JP) ; Kataoka; Ikuo; (Ueda-shi,
Nagano, JP) ; Sato; Shinya; (Ueda-shi, Nagano,
JP) ; Ikari; Takaaki; (Shinagawa-ku, Tokyo,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Marelli Corporation |
Saitama-shi, Saitama |
|
JP |
|
|
Family ID: |
1000005666479 |
Appl. No.: |
16/634478 |
Filed: |
July 25, 2018 |
PCT Filed: |
July 25, 2018 |
PCT NO: |
PCT/JP2018/027980 |
371 Date: |
January 27, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B22C 19/00 20130101;
B22C 9/08 20130101 |
International
Class: |
B22C 9/08 20060101
B22C009/08; B22C 19/00 20060101 B22C019/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 28, 2017 |
JP |
2017-146981 |
Claims
1. A casting mold for molding a cast part by filling molten metal
into an internal space in which a structure is installed, the
casting mold comprising: a molding wall portion configured to form
the internal space; and a filling port configured to open at the
molding wall portion, the filling port being configured to allow
the molten metal to flow into the internal space, wherein the
structure is a metal pipe having a spiral portion, and a center
line of the filling port intersects a curved surface of the spiral
portion of the structure in a tangent line direction.
2. The casting mold according to claim 1, wherein a pair of the
filling ports configured to extend in directions in which the pair
of filling ports are gradually separated away from each other
towards the internal space from a runner for guiding the molten
metal.
3. The casting mold according to claim 1, wherein the molding wall
portion is provided with a fin molding portion for molding a fin in
the cast part.
4. The casting mold according to claim 1, further comprising a
small filling port having an opening width smaller than the filling
port, the small filling port being configured such that a center
line thereof intersect the surface of the structure at a
substantially perpendicular contact angle.
5. The casting mold according to claim 4, wherein the small filling
port faces the internal space so as to face a gap formed in the
structure.
6. A manufacturing method of a cast part for molding the cast part
by filling molten metal into an internal space of a casting mold in
which a structure is installed, wherein the casting mold is
provided with a molding wall portion configured to form the
internal space; and a filling port configured to open at the
molding wall portion, the filling port being configured to allow
the molten metal to flow into the internal space, the structure is
a metal pipe having a spiral portion, a center line of the filling
port intersect a curved surface of the spiral portion of the
structure in a tangent line direction, and the manufacturing method
comprising a filling step for filling the molten metal into the
internal space through the filling port.
7. The manufacturing method of the cast part according to claim 6,
wherein a spiral metal pipe is cast as the structure.
Description
[0001] The present application claims priority to Japanese Patent
Application No. 2017-146981 filed on Jul. 28, 2017, the entire
disclosure of which is incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates to a casting mold for molding
a cast part and a manufacturing method of the cast part.
BACKGROUND
[0003] JP47-30053U discloses a heat exchanger in which a spiral
pipe, through which fluid flows, and a heat generating sheathed
heater are cast into a cast part.
[0004] In the manufacture of this type of heat exchanger,
structures such as the pipe and the sheathed heater are installed
in a casting mold, before a molten metal is filled into the casting
mold. The molten metal thus filled is solidified to form the cast
part. The cast part taken out from the casting mold includes
built-in pipe and sheathed heater.
SUMMARY
[0005] However, when the above-mentioned cast part is formed by,
for example, a die casting method, there is a risk in that, as the
molten metal injected into the casting mold at high speed hits the
structure, the structure such as the pipe, etc. may be
deformed.
[0006] An object of the present invention is to prevent deformation
of a structure cast into a cast part.
[0007] According to an aspect of the present invention, there is
provided a casting mold for molding a cast part by filling molten
metal into an internal space in which a structure is installed, the
casting mold comprising: a molding wall portion forming the
internal space; and a filling port opens at the molding wall
portion, the filling port allows the molten metal to flow into the
internal space, wherein a center line of the filling port intersect
a surface of the structure at a non-perpendicular contact
angle.
[0008] In addition, according to an aspect of the present
invention, there is provided a manufacturing method of a cast part
for molding the cast part by filling molten metal into an internal
space of a casting mold in which a structure is installed, wherein
the casting mold is provided with a molding wall portion forming
the internal space; and a filling port opens at the molding wall
portion, the filling port allows the molten metal to flow into the
internal space, a center line of the filling port intersects a
surface of the structure at a non-perpendicular contact angle, and
the manufacturing method including: a filling step for filling the
molten metal into the internal space through the filling port.
[0009] According to the above-described aspect, the molten metal
flow flowing into the internal space from the filling port flows
along the surface of the structure, and the molten metal flow is
suppressed from hitting from the direction perpendicular to the
surface of the structure. With such a configuration, the load
imparted to the structure by the molten metal flow is suppressed to
the minimum, and therefore, it is possible to prevent deformation
of the structure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a vertical cross-sectional view showing a casting
mold according to an embodiment of the present invention;
[0011] FIG. 2 is a longitudinal cross-sectional view taken along a
line II-II in FIG. 1;
[0012] FIG. 3 is a lateral cross-sectional view taken along a line
III-III in FIG. 2;
[0013] FIG. 4 is a lateral cross-sectional view showing a
modification of the casting mold; and
[0014] FIG. 5 is a lateral cross-sectional view showing another
modification of the casting mold.
DETAILED DESCRIPTION
[0015] Embodiments of the present invention will be described below
with reference to the attached drawings.
[0016] FIGS. 1 to 4 are cross-sectional views showing a casting
device 100 to which a casting mold 30 according to the present
embodiment is applied. For simplification of the description, a
part of the casting device 100 is omitted in the drawing.
[0017] The casting device 100 for the die casting method is
provided with a pressurizing part (piston) 7 for pressurizing a
molten metal injected into an injection chamber 6 and the casting
mold 30 forming an internal space 90 that is filled with the molten
metal discharged from the injection chamber 6 by the pressurizing
part 7. The molten metal is obtained by melting a metal such as an
aluminum alloy, for example. As will be described later, in the
casting mold 30, a cast part 70 is molded as the molten metal
filled in the internal space 90 is solidified.
[0018] The casting mold 30 is provided with a fixed mold 25, and a
movable mold 21, lateral slides 22 and 23, and a core 24 that are
removed after molding. In the casting mold 30, the internal space
90 is formed as the movable mold 21, the lateral slides 22 and 23,
and the core 24 are moved in the direction indicated by an outline
arrow with respect to the fixed mold 25 and are held at
predetermined positions.
[0019] In the internal space 90 of the casting mold 30, a heater 10
is installed as a structure to be cast into the cast part 70.
[0020] The heater 10 is a sheathed heater provided with a heat
generating portion (not shown), which generates heat by
energization, and a metal pipe (pipe) 10a for accommodating the
heat generating portion. The heater 10 is not limited thereto, and
may also be, for example, a PTC (Positive Temperature Coefficient)
heater.
[0021] The heater 10 has end portions 13 and 14 serving as fixed
portions supported by the casting mold 30 and a spiral extending
portion 15 that extends from the end portions 13 and 14. Terminals
16 and 17 to which electrical wirings are connected are
respectively provided at the distal ends of the end portions 13 and
14.
[0022] In the extending portion 15, the metal pipe 10a is spirally
wound about the center line O. As shown in FIGS. 1 and 2, the metal
pipe 10a is wound in the center line O direction. As shown in FIG.
3, the metal pipe 10a is wound in a substantially circular ring
shape when viewed from the center line O direction.
[0023] The two end portions 13 and 14 extend substantially in
parallel with each other from both ends of the extending portion
15. As shown in FIG. 1, the end portions 13 and 14 are formed so as
to be substantially perpendicular with respect to the center line
O. As shown in FIG. 2, the end portions 13 and 14 are respectively
located in the vicinities of two opposing corner portions in the
internal space 90.
[0024] The cast part 70 has a cylindrical shaped cylinder portion
71, into which the extending portion 15 is cast, and a plate-like
lid portion 72, into which the end portions 13 and 14 are cast. The
cylinder portion 71 and the lid portion 72 are integrally formed.
The cylinder portion 71 has a plurality of fins that protrude out
from its outer surface. It should be noted that the cast part 70
may have a single block shape into which the extending portion 15
and the end portions 13 and 14 are cast, without having the lid
portion 72.
[0025] The casting mold 30 has a molding wall portion 32 for
molding the cast part 70 and hole-shaped supporting portions 33 and
34 for supporting the end portions 13 and 14 of the heater 10.
[0026] The molding wall portion 32 has a wall portion 35 for
molding the cylinder portion 71, a wall portion 36 for molding the
lid portion 72, and hole-shaped wall portions 37 and 38 for molding
portions connecting the cylinder portion 71 and the lid portion
72.
[0027] The casting mold 30 has filling ports 42 to 44 that open to
the internal space 90 and a runner 40 through which the injection
chamber 6 is communicated with the internal space 90 through the
filling ports 42 to 44.
[0028] The lower filling port 42 facing a lower portion of the
internal space 90 opens to a lower end surface of the wall portion
36. The lid portion 72 of the cast part 70 is formed by the molten
metal that is filled into the internal space 90 in the wall portion
36 from the lower filling port 42.
[0029] The filling ports 43 and 44 facing a side portion of the
internal space 90 open to a side end surface 35a of the wall
portion 35. The cylinder portion 71 of the cast part 70 is formed
by the molten metal filled into the internal space 90 in the wall
portion 35 from the filling ports 43 and 44.
[0030] Next, a process of casting the cast part 70 by the casting
device 100 will be described.
[0031] First, an installation process of installing the heater 10
in the internal space 90 of the casting mold 30 is performed. In
this installation process, the heater 10 is first assembled to the
movable mold 21. At this time, the end portions 13 and 14 of the
heater 10 are inserted into the hole-shaped supporting portions 33
and 34 through the hole-shaped wall portions 37 and 38, and
thereby, the heater 10 is installed at a predetermined position in
the internal space 90. Subsequently, the movable mold 21, the
lateral slides 22 and 23, and the core 24 are set to the fixed mold
25, so as the internal space 90 to be formed.
[0032] Next, a filling step of filling the internal space 90 with
the molten metal is performed. In this filling step, the internal
space 90 is first filled with an active gas (oxygen). Next, the
high-temperature molten metal is injected into the injection
chamber 6, and the pressurizing part 7 is driven to pressurize the
molten metal. As a result, the molten metal pushed out from the
injection chamber 6 flows into the internal space 90 from the
filling ports 42 to 44 through the runners 40, as indicated by
arrows in FIG. 1. At this time, the molten metal is injected into
the internal space 90 as a high-speed spray from the filling ports
42 to 44. As a result, in the internal space 90, a vacuum state is
formed as the active gas is combined with the molten metal, and
thereby, the molten metal is filled completely without forming a
hollow space. Thus, formation of a cavity in the cast part 70 is
prevented. It should be noted that the present invention is not
limited to this, and for example, a gas vent hole may be formed in
the casting mold 30 such that the air in the internal space 90 is
discharged to the outside as the internal space 90 is filled with
the molten metal.
[0033] Thereafter, in the casting mold 30, the molten metal filled
in the internal space 90 is solidified to form the cast part 70.
The movable mold 21, the lateral slides 22 and 23, and the core 24
are then separated from the cast part 70, so as the cast part 70
removed from the fixed mold 25.
[0034] As described above, the cast part 70 is manufactured. The
cast part 70 with the built-in heater 10 is assembled to a tank
(not shown) as a heater unit. In the heater unit, the heat
generated by the heater 10 is transferred to a fluid (medium)
circulating in the tank via the cast part 70 so as to heat the
fluid.
[0035] Next, the arrangement of the heater 10 and the filling ports
43 and 44 with respect to the internal space 90 in the casting mold
30 will be described.
[0036] The wall portion 35 and the filling ports 43 and 44 of the
casting mold 30 form a weir that guides the molten metal, which has
been injected into the internal space 90, to predetermined
positions.
[0037] As shown in FIG. 2, the filling ports 43 and 44 have a
substantially rectangular channel cross-sectional shape. The
filling ports 43 and 44 are formed to have a slit shape in which
the opening width in the center line O direction of the heater 10
is larger than the opening width in the direction perpendicular to
the center line O.
[0038] The configuration of the casting mold 30 is not limited to
that in which the slit shaped filling ports 43 and 44 extend in
parallel with the center line O, and the casting mold 30 may have a
configuration in which a plurality of filling ports are aligned in
the direction of the center line O.
[0039] In FIG. 3, channel center lines F43 and F44 of a pair of
filling ports 43 and 44 are inclined symmetrically with respect to
the center line P perpendicular to the center line O of the heater
10 such that the center line O is located between the channel
center lines F43 and F44. The filling ports 43 and 44 are formed
such that the respective channel center lines F43 and F44 intersect
the heater 10 by avoiding the central part of the heater 10 (the
portion including the center line P). In other words, the filling
ports 43 and 44 are formed such that the respective channel center
lines F43 and F44 intersect a tangent line T in contact with a
curved surface of the heater 10 at a non-perpendicular contact
angle .theta.. It should be noted that the contact angle .theta.
refers to the angle formed with the tangent line T at the position
where each of the channel center lines F43 and F44 of the filling
ports 43 and 44 intersects the tangent line T in contact with the
surface of the heater 10. In other words, the filling ports 43 and
44 are formed such that the respective channel center lines F43 and
F44 intersect the tangent line T in contact with the curved surface
of the heater 10 so as not to be perpendicular.
[0040] As shown in FIG. 3, the pair of filling ports 43 and 44
extend in the directions in which they are gradually separated away
from each other from a chamber 49 of the runner 40 towards the
internal space 90. The filling ports 43 and 44 extend along the
outer circumference of the spiral heater 10.
[0041] The filling ports 43 and 44 are arranged so as to
respectively face gaps 53 and 54 around the heater 10. The gaps 53
and 54 are spaces formed between the outer circumference of the
heater 10 and the molding wall portion 32.
[0042] With such a configuration, the molten metal injected from
the filling ports 43 and 44 flows into the internal space 90
through the gaps 53 and 54 along the curved surface of the heater
10.
[0043] As described above, according to the present embodiment,
there is provided the casting mold 30 provided with the filling
ports 43 and 44 through which the molten metal is filled into the
internal space 90 in which the heater 10 is installed.
[0044] When the molten metal is filled as described above, the
molten metal in the form of a spray flows into the internal space
90 from the filling ports 43 and 44 at a speed of, for example,
about 50 m/s. If the high-speed molten metal flow injected from the
filling ports 43 and 44 hits the heater 10 from the direction
perpendicular to the tangent line T in contact with the surface of
the heater 10, the load imparted to the heater 10 is increased, and
therefore, there is a risk in that the heater 10 may be
deformed.
[0045] As a countermeasure against such a problem, according to the
present embodiment, for the heater 10 (the structure), the casting
mold 30 is provided with the molding wall portion 32 forming the
internal space 90 and the filling ports 43 and 44 that open at the
molding wall portion 32 and allow the molten metal to flow into the
internal space 90. In this configuration, the channel center lines
F43 and F44 of the filling ports 43 and 44 intersect the surface of
the heater 10 at the non-perpendicular contact angle .theta..
[0046] By being configured as described above, the molten metal
injected from the filling ports 43 and 44 is suppressed from
hitting the heater 10 from the direction perpendicular to the
surface of the heater 10 and flows into the internal space 90 along
the surface of the heater 10. With such a configuration, because
the load imparted to the heater 10 by the molten metal flow is
suppressed to the minimum, it is possible to prevent the
deformation of the heater 10. Because the molten metal flow
smoothly flows into the internal space 90 along the surface of the
heater 10, the molten metal is completely filled into the
respective portions in the internal space 90 without forming a
hollow space. With such a configuration, with the cast part 70, the
formation of the internal cavities is prevented and improvement in
the quality is made possible.
[0047] In addition, according to the present embodiment, the
configuration in which the pair of filling ports 43 and 44 extend
in the directions in which they are gradually separated away from
each other towards the internal space 90 from the chamber 49 of the
runner 40 guiding the molten metal is employed.
[0048] By being configured as described above, the gap between the
opening portions of the filling ports 43 and 44 to the chamber 49
is smaller than the gap between the opening portions of the filling
ports 43 and 44 to the internal space 90, and so, it is possible to
reduce the volume of the chamber 49. With such a configuration, it
is possible to reduce an amount of waste material after the molten
metal is solidified in the chamber 49.
[0049] It should be noted that the configuration of the casting
mold 30 is not limited to that in which two filling ports 43 and 44
are provided, and the casting mold 30 may have a configuration in
which single filling port is provided.
[0050] In addition, according to the present embodiment, the heater
10 forms the gaps 53 and 54 in the internal space 90. In this
configuration, the filling ports 43 and 44 face the internal space
90 so as to respectively face the gaps 53 and 54.
[0051] By being configured as described above, the molten metal
injected from the internal space 90 from the filling ports 43 and
44 towards the gaps 53 and 54 flows into the respective portions in
the internal space 90 through the gaps 53 and 54. With such a
configuration, the high-speed molten metal flow is suppressed from
hitting the heater 10, and so, the deformation of the heater 10 due
to the load applied by the molten metal flow is prevented. Because
the molten metal flow smoothly flows into the internal space 90
through the gaps 11, the molten metal is completely filled into the
respective portions in the internal space 90 without forming a
hollow space. With such a configuration, with the cast part 70, the
formation of the internal cavities is prevented and improvement in
the quality is made possible.
[0052] In addition, according to the present embodiment, the
casting mold 30 is provided with the plurality of supporting
portions 33 and 34. The heater 10 is configured to have the
extending portion 15 that is provided so as to extend between the
plurality of end portions 13 and 14.
[0053] By being configured as described above, the extending
portion 15 of the heater 10 is supported by the plurality of end
portions 13 and 14 at the both ends, and so, bending stress caused
by the molten metal flow is suppressed to the minimum. With such a
configuration, it is possible to effectively prevent the
deformation of the heater 10.
[0054] Thus, according to the present embodiment, it is possible to
provide the manufacturing method of the cast part 70 for
manufacturing the cast part 70 into which the heater 10 is cast
using the casting mold 30.
[0055] In addition, according to the present embodiment, it is
possible to provide the manufacturing method of the cast part 70
for manufacturing the cast part 70 into which the spiral metal pipe
10a is cast as the structure installed in the internal space
90.
[0056] With such a configuration, in the heater unit, the shape of
the spiral metal pipe 10a prone to be deformed is maintained, and
the desired performance can be obtained.
[0057] Next, a modification of the casting mold 30 shown in FIG. 4
will be described.
[0058] The casting mold 30 has a small filling port 45 having the
opening width smaller than those of the filling ports 43 and 44 in
the direction perpendicular to the center line O (in the up-down
direction in FIG. 4).
[0059] The small filling port 45 is formed to have the slit shape
that opens at a position aligned with the filling ports 43 and 44
in a line along the center line O.
[0060] A channel center line F45 of the small filling port 45
extends on the center line P and intersects the tangent line T for
the surface of the heater 10 at the substantially perpendicular
angle. In other words, the small filling port 45 is configured such
that the channel center line F45 intersects the surface of the
heater 10 at the substantially perpendicular contact angle.
[0061] By being configured as described above, in the filling step,
the molten metal flow injected from the small filling port 45 hits
the central part of the heater 10. The molten metal flow is
decelerated as the molten metal flow passes through the small
filling port 45 and resistance is imparted thereto, and therefore,
even if the molten metal flow injected from the small filling port
45 hits the central part of the heater 10, the load imparted to the
heater 10 by the molten metal flow is suppressed to the minimum.
With such a configuration, it is possible to prevent the
deformation of the heater 10.
[0062] Next, a modification of the casting mold 30 shown in FIG. 5
will be described.
[0063] As shown in FIG. 5, the pair of filling ports 43 and 44 are
formed such that the respective channel center lines F43 and F44
extend substantially in parallel with the center line P of the
heater 10 perpendicular to the center line O such that the center
line O of the heater 10 is located between the channel center lines
F43 and F44.
[0064] The filling ports 43 and 44 are formed such that the
respective channel center lines F43 and F44 intersect the tangent
line T for the surface of the heater 10 at the angle which is not
perpendicular. In other words, the filling ports 43 and 44 are
configured such that the respective channel center lines F43 and
F44 intersect the surface of the heater 10 at the non-perpendicular
contact angle.
[0065] Also in this case, the molten metal injected from the
filling ports 43 and 44 flows into the internal space 90 along the
surface of the heater 10. With such a configuration, because the
load imparted to the heater 10 by the molten metal flow is
suppressed to the minimum, the deformation of the heater 10 due to
the molten metal flow is prevented.
[0066] Embodiments of the present invention were described above,
the above embodiments are merely examples of applications of this
invention, and the technical scope of this invention is not limited
to the specific constitutions of the above embodiments.
[0067] Although the present invention is suitable as the casting
mold for casting the heater, it may also be applicable to the
casting mold for casting the structure other than the heater.
[0068] Although the present invention is suitable as the casting
method by the die casting method in which the molten metal is
pressurized and filled into the casting mold, it may also be
applicable to other casting methods.
* * * * *