U.S. patent application number 13/338947 was filed with the patent office on 2013-05-23 for mold and method for sectionally adjusting cooling efficiency of the mold.
This patent application is currently assigned to METAL INDUSTRIES RESEARCH AND DEVELOPMENT CENTRE. The applicant listed for this patent is Yi-Chiun Chen, Tzu-Hsin Chiang, Chinh-Yu Chuang, Ming-Fu Lee, Wei-Liang Liu, Wen-Yen Wang. Invention is credited to Yi-Chiun Chen, Tzu-Hsin Chiang, Chinh-Yu Chuang, Ming-Fu Lee, Wei-Liang Liu, Wen-Yen Wang.
Application Number | 20130125603 13/338947 |
Document ID | / |
Family ID | 48425491 |
Filed Date | 2013-05-23 |
United States Patent
Application |
20130125603 |
Kind Code |
A1 |
Liu; Wei-Liang ; et
al. |
May 23, 2013 |
MOLD AND METHOD FOR SECTIONALLY ADJUSTING COOLING EFFICIENCY OF THE
MOLD
Abstract
The present invention provides a method for sectionally
controlling a cooling efficiency of a mold. The method comprises
steps of: (a) configuring at least a cooling passage including a
first section having a first heat-dissipating inner surface area
and a second section having a second heat-dissipating inner surface
area in the mold; and (b) adjusting the first and the second
heat-dissipating inner surface areas unequally by using a
heat-dissipating element.
Inventors: |
Liu; Wei-Liang; (Kaohsiung,
TW) ; Chiang; Tzu-Hsin; (Kaohsiung, TW) ; Lee;
Ming-Fu; (Kaohsiung, TW) ; Wang; Wen-Yen;
(Kaohsiung, TW) ; Chuang; Chinh-Yu; (Kaohsiung,
TW) ; Chen; Yi-Chiun; (Kaohsiung, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Liu; Wei-Liang
Chiang; Tzu-Hsin
Lee; Ming-Fu
Wang; Wen-Yen
Chuang; Chinh-Yu
Chen; Yi-Chiun |
Kaohsiung
Kaohsiung
Kaohsiung
Kaohsiung
Kaohsiung
Kaohsiung |
|
TW
TW
TW
TW
TW
TW |
|
|
Assignee: |
METAL INDUSTRIES RESEARCH AND
DEVELOPMENT CENTRE
Kaohsiung
TW
|
Family ID: |
48425491 |
Appl. No.: |
13/338947 |
Filed: |
December 28, 2011 |
Current U.S.
Class: |
72/342.3 ;
165/185 |
Current CPC
Class: |
B21D 37/16 20130101 |
Class at
Publication: |
72/342.3 ;
165/185 |
International
Class: |
B21D 37/16 20060101
B21D037/16; F28F 7/00 20060101 F28F007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 17, 2011 |
TW |
100142109 |
Claims
1. A method for sectionally controlling a cooling efficiency of a
mold, comprising steps of: configuring at least a cooling passage
including a first section having a first heat-dissipating inner
surface area and a second section having a second heat-dissipating
inner surface area in the mold; and adjusting the first and the
second heat-dissipating inner surface areas unequally by using a
heat-dissipating element.
2. A method as claimed in claim 1, wherein the mold includes a
hot-stamping die.
3. A method as claimed in claim 1, wherein the heat-dissipating
element includes at least one of a fin and a foil.
4. A method as claimed in claim 1, wherein the step of adjusting
the first and the second heat-dissipating inner surface areas is
performed by increasing at least one of the first heat-dissipating
inner surface area and the second heat-dissipating inner surface
area.
5. A method as claimed in claim 1, wherein the cooling passage
includes a first and a second cooling sub-passages having the first
and the second heat-dissipating inner surface areas
respectively.
6. A method as claimed in claim 1, wherein the first and the second
sections are disposed in different locations of the mold.
7. A method as claimed in claim 1, wherein the cooling passage
includes an upstream and a downstream sections, the first section
is located at the upstream section, and the second section is
located at the downstream section.
8. A method for sectionally controlling a cooling efficiency of a
mold, comprising steps of: configuring a cooling passage having a
heat-dissipating inner surface area in the mold; and disposing a
heat-dissipating element in the cooling passage for causing the
heat-dissipating inner surface area to be inhomogeneous.
9. A method as claimed in claim 8, wherein the heat-dissipating
element includes at least one of a fin and a foil.
10. A method as claimed in claim 8, wherein the cooling passage
includes an upstream and a downstream sections, and the
heat-dissipating element is disposed at one of the upstream section
and the downstream section.
11. A method as claimed in claim 8, wherein the cooling passage
includes a first and a second cooling sub-passages having different
heat-dissipating inner surface areas.
12. A method as claimed in claim 11, wherein the first and the
second cooling sub-passages are disposed in different locations of
the mold.
13. A method as claimed in claim 8, wherein the mold includes a
hot-stamping die.
14. A mold for molding an object comprising: a cooling passage
device having a heat-dissipating inner surface area; and a
heat-dissipating element disposed in the cooling passage device for
causing the heat-dissipating inner surface area to be
inhomogeneous.
15. A mold as claimed in claim 14, further comprising: a lower mold
base having a top surface and including a cooling channel disposed
on the top surface; and a lower mold cover disposed above the lower
mold base, and covering the cooling channel to form the cooling
passage device.
16. A mold as claimed in claim 15, wherein the heat-dissipating
element is disposed on at least one of the lower mold base and the
lower mold cover.
17. A mold as claimed in claim 14, wherein the mold includes a
hot-stamping die.
18. A mold as claimed in claim 14, wherein the heat-dissipating
element includes at least one of a fin and a foil.
19. A mold as claimed in claim 14, wherein the cooling passage
device includes a first and a second cooling passages, and the
heat-dissipating element is disposed in at least one of the first
and the second cooling passages.
20. A mold as claimed in claim 19, wherein the first and the second
cooling passages are disposed in different locations of the mold.
Description
FIELD OF THE INVENTION
[0001] The present invention claims the benefits of priority from
the Taiwanese Patent Application No. 100142109, filed on Nov. 17,
2011, the contents of the specification of which are hereby
incorporated herein by reference. The present invention relates to
a mold and a method for adjusting cooling efficiency, particularly
a hot-stamping mold and a method of sectionally adjusting the
cooling efficiency of the hot-stamping mold.
BACKGROUND OF THE INVENTION
[0002] The production method for a cooling water passage according
to the prior art is to drill a mold to form tunnels therein for
allowing cooling water to flow in the tunnels. Due to the physical
limitations of the drilling machine, each of the tunnels formed in
the mold is in one direction, i.e. strait lines. However, the
contours of a mold are usually curvature. Thus, the distance
between the cooling water passages made by drilling inside the mold
and the outer surface of the mold cannot be constant, which results
in deficiencies such as inhomogeneous cooling effect at different
areas and ineffective temperature control during a hot-stamping
process using the mold.
[0003] The hot-stamping technology has advantages including
easy-forming, good mechanical properties of the formed elements,
small amount of springing back and etc. The material processed with
hot-stamping is heated up to 900 degrees Celsius and then is cooled
down rapidly (quenched), which improves the strength of the
material in a great deal. Such a quenching effect obtained with a
hot-stamping mold (or die) has a large influence to the mechanical
properties of the end products, particularly in the field of
automobile industry where the hot-stamping process has been broadly
adopted. The mechanical properties (for example, hardness and
vibration absorption) of the end products of the automobile
industry are of series concerns for the sake of safety as well as
weight reduction.
[0004] The allocation design for those cooling passages according
to the prior art is focused the effect of heat release only, but
never considers an improvement for homogeneous heat transferring
during and after the hot-stamping process which requires precise
calculations for better structure designs of the cooling passages.
Consequently, the use of many of these hot-stamping molds results
in even mechanical properties of the products, or even causes
deformations or cracks of the end products.
[0005] Some of the prior arts provide methods of changing the
cooling rate by controlling the water flow, employing multiple
number of cooling passages, or changing the dimensions (such as the
cross section of the cooling tunnel) of the mold, which may resolve
the issue of broken steel plates due to abrupt cooling. However,
such methods involve exhausting calculations for determining the
metal mold dimensions based on the cooling speeds, and are not
applicable for producing products with different mechanical
properties at various portions. Besides, with the restrictions of
the shape of the mold, sometimes it is not applicable to increase
the density of cooling tunnels inside the mold.
SUMMARY OF THE INVENTION
[0006] To overcome the abovementioned defects of the prior arts,
the present invention provides novel structural designs of the
cooling passages for sectionally adjusting the cooling efficiency
of a mold, without changing the density of the cooling passages or
the cooling water flow rate. The present invention unequally
adjusts the heat-dissipation rate or cooling efficiency at
different portions of the mold by changing the heat-dissipation
surface of the cooling passages at different areas so as to obtain
different mechanical properties such as hardness and strength of
the products at different areas thereof.
[0007] According to one embodiment of the present invention, the
present provides a method for sectionally controlling a cooling
efficiency of a mold. The method comprises steps of: (a)
configuring at least a cooling passage including a first section
having a first heat-dissipating inner surface area and a second
section having a second heat-dissipating inner surface area in the
mold; and (b) adjusting the first and the second heat-dissipating
inner surface areas unequally by using a heat-dissipating
element.
[0008] In accordance with another aspect of the present invention,
a method for sectionally controlling a cooling efficiency of a mold
is provided. The method comprises steps of: (a) configuring a
cooling passage having a heat-dissipating inner surface area in the
mold; and (b) disposing a heat-dissipating element in the cooling
passage for causing the heat-dissipating inner surface area to be
inhomogeneous.
[0009] In accordance with a further aspect of the present
invention, a mold for molding an object is provided. The mold
comprises a cooling passage and a heat-dissipating element. The
cooling passage device has a heat-dissipating inner surface area.
The heat-dissipating element is disposed in the cooling passage
device for causing the heat-dissipating inner surface area to be
inhomogeneous.
[0010] The above objects and advantages of the present invention
will be more readily apparent to those ordinarily skilled in the
art after reading the details set forth in the descriptions and
drawings that follow, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIGS. 1A to 1C are schematic diagrams showing a mold having
multiple cooling passages in accordance with one embodiment of the
present invention;
[0012] FIG. 2 is a schematic diagram showing another embodiment of
the heat-dissipating element;
[0013] FIGS. 3A to 3E illustrates a method for manufacturing a mold
having multiple cooling passages according to the present
invention;
[0014] FIG. 4 is a schematic diagram showing a cross section
according to a further embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0015] The present invention will now be described more
specifically with reference to the following embodiments. It is to
be noted that the following descriptions of preferred embodiments
of this invention are presented herein for the purposes of
illustration and description only; it is not intended to be
exhaustive or to be limited to the precise form disclosed.
[0016] An objective of the present invention is to provide a novel
design for cooling passages in a mold, so as to render a product
having different mechanical properties at different portions
thereof. The method is to dispose heat-dissipating elements in the
cooling passages of the mold for causing the heat-dissipating inner
surface area inhomogeneous and resulting in different cooling
efficiencies during the cooling period of the product manufacturing
process.
[0017] Please refer to FIGS. 1A to 1C, which are schematic diagrams
showing a lower mold having multiple cooling passages in accordance
with one embodiment of the present invention. Notably, the present
embodiment is also applicable to an upper mold (not shown). The
lower mold 10 illustrated in FIG. 1A can be used in hot-stamping
processes or other mechanical manufacturing processes such as die
casting. A mold used in the hot-stamping process is sometimes
called a hot-stamping die. According to FIG. 1A, the lower mold 10
comprises several cooling passages 11. FIGS. 1B and 1C illustrate
the cross sections A-A and B-B of the lower mold 10 respectively.
It is observed that there are heat-dissipating elements 12, such as
fins, configured inside of the cooling passage 11 at the cross
section A-A while no heat-dissipating element 12 in the cooling
passage 11 at the cross section B-B. For one particular cooling
passage 11, says the one at the upper right corner, it is
appreciated that the heat-dissipating inner surface area (not
shown) of the section near the cross section A-A is larger than
that of the section near the cross section B-B, and therefore the
cooling efficiencies of the section near A-A is higher than that of
the section near B-B. The coolants available for the embodiment
includes water, vapor, liquid helium, oil, air, and any other
material applicable for the use of cooling inside a mold.
[0018] The heat-dissipating element 12 shown in FIG. 1B can be
either a fastened or a replaceable element. Furthermore, any type
of element capable of increasing the heat-dissipating surface of
the cooling passage can be used as a heat-dissipating element
according to the present invention. FIG. 2 illustrates another
embodiment of the heat-dissipating element which is a flexible
metal foil 20 fastened by a fastening element 21 in a cooling
passage 22. The metal foil 20 may also be attached on the inner
wall of the cooling passage 22 by way of wielding or sticking.
Optionally, the material of the metal foil 20 can be any metal with
good heat conductivity such as, but not limited to gold, silver,
copper, aluminum or alloys of the above metals. A variety of shapes
are available as options of the metal foil 20, as long as the area
of the heat-dissipating surface can be increased.
[0019] The embodiments set forth above according to the present
invention can be realized with many manufacturing processes known
to the art. The present invention simply provides an embodiment of
a method for manufacturing a mold with heat-dissipating elements
disposed in at least one cooling passage of the mold. Referring to
FIGS. 3A to 3E, the method comprises the following steps: Firstly,
providing a mold base 30 which has a shape the same with that of
the embodiment shown in FIGS. 1A to 1C; Secondly, configuring one
or plural cooling passages 31 around the working surface of the
mold base 30, wherein each of the cooling passage 31 has a
heat-dissipating inner surface area, as illustrated in FIG. 3B;
Thirdly, providing a lower mold cover 32. Preferably, the lower
mold cover 32 is preferably of a constant thickness, so the cooling
passages 31 can be completed with a constant distance to the actual
working surface of the finished mold as illustrated in FIG. 3E when
the lower mold base 31 is covered by the lower mold cover 32;
Fourthly, disposing heat-dissipating elements 33 in the cooling
passages 31 for causing the heat-dissipating inner surface area to
be inhomogeneous. Optionally, the heat-dissipating elements 33 may
include fins as illustrated in FIG. 3D, the foil 20 in FIG. 2 or
other types of element applicable for adjusting the
heat-dissipating surface area of the cooling passages 31. The
heat-dissipating elements 33 may be attached on the inner wall of
the cooling passage 31 by wielding or sticking, or be fastened with
fasteners. Preferably, the heat-dissipating elements 33 are
disposed on locations of the lower mold cover 32 corresponding to
the required positions inside the cooling passages 31 when the
lower mold cover 32 covers the lower mold base 31 (referring to
FIG. 3E).
[0020] Due to the existing of the heat-dissipating elements 33, the
heat-dissipating surface area of this portion is larger than that
of the other portions without the heat-dissipating elements 33,
i.e., the heat-dissipating surface area in the cooling passage 31
is inhomogeneous. Thus, the cooling effects along the cooling
passage 31 can be sectionally controlled by using the
heat-dissipating elements 33. The skilled person in the art may
adjust the heat-dissipating inner surface areas unequally by using
a heat-dissipating element 33. For some products that require at
least two different types of performance in terms of mechanical
properties at different portions, for example one portion of an
automobile body to be strong for maintaining its main structure for
the safety of the driver and passenger while the other portion to
be ductile and vibration absorbable in case of a collision, the
present invention provides a method as well as a mold structure
that unequally adjusts the heat-dissipation rate or cooling
efficiency at different portions of the mold by changing the
heat-dissipation surface areas of the cooling passages at different
sections so as to obtain different mechanical properties of the
products at different portions thereof.
[0021] Please refer to FIG. 4, which schematics a cross section of
another embodiment of the present invention. According to FIG. 4, a
mold 40 includes cooling passages 41, and heat dissipating elements
42 are configured in some of the cooling passages 41 located in the
right portion of the mold 40 for increasing the heat-dissipating
inner surface area thereof. Comparing the two (right and left)
portions of the mold 40 in FIG. 4, it is appreciated that the
cooling efficiency at the right portion is higher than that of the
left portion due to the different heat-dissipating inner surface
areas thereinbetween. Consequently, the mechanical properties at
the two different portions of a product manufactured with the mold
40 will be different.
[0022] According to the abovementioned concept of mold design, the
heat dissipating element 42 such as a fin can be utilized to adjust
or control the heat-dissipating area of the cooling passages 41
inside a mold 40 based on the requirements relevant to the
mechanical properties of different portions of the product without
changing the locations of the cooling passages 41. Notably, such
adjustment or control includes either an increase or a decrease of
the number, density or surface area of the heat-dissipating
elements 42 configured in the cooling passages 41. The present
invention has the advantages of increasing the product's quality as
well as performance and reducing product defect rate by sectionally
controlling the heat-dissipating surface area without changing the
mold structure and the layout of the cooling passages inside the
mold.
[0023] The cooling passage according to the present invention is a
device which may be composed of a plurality of sub-passages
connected in parallel or not connected, or a single cooling passage
route. Therefore, the device can be called a cooling passage
device, which is built in one piece when the cooling passage device
is either a single passage route or a plurality of sub-passages
connected in parallel. Preferably, a negative pressure is applied
to the coolant flowing in the cooling passages 11, 31, 41 to
increase the flow rate and the cooling rate. The negative pressure
can be obtained by using a vacuum pump or a negative pressure pump.
Another preferred embodiment is to increase or decrease the
dimension of a particular portion of the cooling passage to adjust
the cooling rate. This concept may be incorporated with the
embodiments of using the heat-dissipating elements 12, 33, 42 set
forth above, to efficiently adjust and control the cooling
efficiency.
[0024] It is also notable that the at least two portions of the
mold 10, 30, 40 having different heat-dissipating inner surface
area can be considered as a first and a second sections which may
be located in right-and-left, front-and-back,
upstream-and-downstream, or any different two locations in the mold
10, 30, 40.
EMBODIMENTS
[0025] 1. A method for sectionally controlling a cooling efficiency
of a mold, comprising steps of:
[0026] configuring at least a cooling passage including a first
section having a first heat-dissipating inner surface area and a
second section having a second heat-dissipating inner surface area
in the mold; and adjusting the first and the second
heat-dissipating inner surface areas unequally by using a
heat-dissipating element.
[0027] 2. The method of embodiment 1, wherein the mold includes a
hot-stamping die.
[0028] 3. The method of embodiment 1, wherein the heat-dissipating
element includes at least one of a fin and a foil.
[0029] 4. The method of embodiment 1, wherein the step of adjusting
the first and the second heat-dissipating inner surface areas is
performed by increasing at least one of the first heat-dissipating
inner surface area and the second heat-dissipating inner surface
area.
[0030] 5. The method of embodiment 1, wherein the cooling passage
includes a first and a second cooling sub-passages having the first
and the second heat-dissipating inner surface areas
respectively.
[0031] 6. The method of embodiment 1, wherein the first and the
second sections are disposed in different locations of the
mold.
[0032] 7. The method of embodiment 1, wherein the cooling passage
includes an upstream and a downstream sections, the first section
is located at the upstream section, and the second section is
located at the downstream section.
[0033] 8. A method for sectionally controlling a cooling efficiency
of a mold, comprising steps of:
[0034] configuring a cooling passage having a heat-dissipating
inner surface area in the mold; and
[0035] disposing a heat-dissipating element in the cooling passage
for causing the heat-dissipating inner surface area to be
inhomogeneous.
[0036] 9. The method of embodiment 8, wherein the heat-dissipating
element includes at least one of a fin and a foil.
[0037] 10. The method of embodiment 8, wherein the cooling passage
includes an upstream and a downstream sections, and the
heat-dissipating element is disposed at one of the upstream section
and the downstream section.
[0038] 11. A method as claimed in claim 8, wherein the cooling
passage includes a first and a second cooling sub-passages having
different heat-dissipating inner surface areas.
[0039] 12. The method of embodiment 11, wherein the first and the
second cooling sub-passages are disposed in different locations of
the mold.
[0040] 13. The method of embodiment 8, wherein the mold includes a
hot-stamping die.
[0041] 14. A mold for molding an object comprising:
[0042] a cooling passage device having a heat-dissipating inner
surface area; and [0043] a heat-dissipating element disposed in the
cooling passage device for causing the heat-dissipating inner
surface area to be inhomogeneous.
[0044] 15. The mold of embodiment 14, further comprising:
[0045] a lower mold base having a top surface and including a
cooling channel disposed on the top surface; and
[0046] a lower mold cover disposed above the lower mold base, and
covering the cooling channel to form the cooling passage
device.
[0047] 16. The mold of embodiment 15, wherein the heat-dissipating
element is disposed on at least one of the lower mold base and the
lower mold cover.
[0048] 17. The mold of embodiment 14, wherein the mold includes a
hot-stamping die.
[0049] 18. The mold of embodiment 14, wherein the heat-dissipating
element includes at least one of a fin and a foil.
[0050] 19. The mold of embodiment 14, wherein the cooling passage
device includes a first and a second cooling passages, and the
heat-dissipating element is disposed in at least one of the first
and the second cooling passages.
[0051] 20. The mold of embodiment 19, wherein the first and the
second cooling passages are disposed in different locations of the
mold.
[0052] While the invention has been described in terms of what is
presently considered to be the most practical and preferred
embodiments, it is to be understood that the invention needs not be
limited to the disclosed embodiments. On the contrary, it is
intended to cover various modifications and similar arrangements
included within the spirit and scope of the appended claims that
are to be accorded with the broadest interpretation so as to
encompass all such modifications and similar structures.
* * * * *