U.S. patent application number 14/035362 was filed with the patent office on 2014-04-03 for cooling device.
This patent application is currently assigned to KABUSHIKI KAISHA TOYOTA JIDOSHOKKI. The applicant listed for this patent is KABUSHIKI KAISHA TOYOTA JIDOSHOKKI. Invention is credited to Naoki KATO, Shogo MORI, Shinsuke NISHI, Yuri OTOBE.
Application Number | 20140090809 14/035362 |
Document ID | / |
Family ID | 50276499 |
Filed Date | 2014-04-03 |
United States Patent
Application |
20140090809 |
Kind Code |
A1 |
MORI; Shogo ; et
al. |
April 3, 2014 |
COOLING DEVICE
Abstract
A cooling device to which a heating element is joinable includes
a base, a plurality of first groups of pin fins and a plurality of
second groups of pin fins. The second groups and the first groups
are arranged alternately in a flow direction in which a cooling
medium flows through a passage of the base. A second outermost pin
fin of each second group is more distant from a side surface of the
base than a first outermost pin fin of each first group. Width
between a side surface of the second outermost pin fin of each
second group and the side surface of the base is the same as or
larger than width between a side surface of the pin fin of each
first group that is adjacent to the first outermost pin fin of the
first group and the side surface of the second outermost pin
fin.
Inventors: |
MORI; Shogo; (Aichi-ken,
JP) ; OTOBE; Yuri; (Aichi-ken, JP) ; KATO;
Naoki; (Aichi-ken, JP) ; NISHI; Shinsuke;
(Aichi-ken, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KABUSHIKI KAISHA TOYOTA JIDOSHOKKI |
Kariya-shi |
|
JP |
|
|
Assignee: |
KABUSHIKI KAISHA TOYOTA
JIDOSHOKKI
Kariya-shi
JP
|
Family ID: |
50276499 |
Appl. No.: |
14/035362 |
Filed: |
September 24, 2013 |
Current U.S.
Class: |
165/104.19 |
Current CPC
Class: |
H01L 2924/0002 20130101;
H01L 23/473 20130101; F28F 3/022 20130101; H01L 2924/0002 20130101;
F28F 3/12 20130101; H01L 2924/00 20130101; F28F 3/02 20130101; F28F
13/06 20130101 |
Class at
Publication: |
165/104.19 |
International
Class: |
F28F 3/02 20060101
F28F003/02 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 28, 2012 |
JP |
2012-217729 |
Claims
1. A cooling device to which a heating element is joinable,
comprising: a base having a passage through which a cooling medium
flows; a plurality of first groups of pin fins located in the
passage and adjacent to the heating element, wherein the pin fins
of each first group are arranged in a width direction that is
perpendicular to a flow direction in which the cooling medium flows
through the passage, wherein one of the pin fins of each first
group that is located closest to a side surface of the base in the
first group is a first outermost pin fin; and a plurality of second
groups of pin fins located in the passage and adjacent to the
heating element, wherein the pin fins of each second group are
arranged in the width direction that is perpendicular to the flow
direction in which the cooling medium flows through the passage,
wherein one of the pin fins of each second group that is located
closest to the side surface of the base in the second group is a
second outermost pin fin, wherein the second groups and the first
groups are arranged alternately in the flow direction, wherein the
pin fins of the second groups and the first groups are provided in
a staggered arrangement, wherein the second outermost pin fin of
each second group is more distant from the side surface of the base
than the first outermost pin fin of each first group, wherein width
between a side surface of the second outermost pin fin of each
second group and the side surface of the base is the same as or
larger than width between a side surface of the pin fin of each
first group that is adjacent to the first outermost pin fin of the
first group and the side surface of the second outermost pin
fin.
2. The cooling device according to claim 1, wherein width between a
side surface of the first outermost pin fin and the side surface of
the second outermost pin fin is the same as the width between the
side surface of the pin fin of each first group that is adjacent to
the first outermost pin fin of the first group and the side surface
of the second outermost pin fin.
3. The cooling device according to claim 1, wherein the first
outermost pin fin is a projection that is formed projecting from
the side surface of the base.
4. The cooling device according to claim 3, wherein the projection
is formed so that a cross section thereof is reduced gradually
toward an end thereof.
5. The cooling device according to claim 1, wherein the heating
element is a semiconductor device that is joined to the base via an
insulating base plate.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a cooling device that cools
a heating element that is joined to a base via a cooling medium
that flows through a passage of the base.
[0002] Japanese Unexamined Patent Application Publication No.
2012-29539 discloses a cooling device having a base on which a
heating element such as an electronic component is mounted from
outside and in which a passage is formed to allow a cooling medium
to flow therethrough for cooling the heating element.
[0003] In the cooling device disclosed by the above Publication, a
plurality of pin fins are provided in a staggered arrangement in
the passage of the base for increasing the area of contact between
the inner surface of the passage and cooling medium. Transferring
the heat radiated from the heating element to the base, the pin
fins promote heat radiation from the inner surface of the passage
to the cooling medium thereby to cool the heating element
efficiently.
[0004] The cooling device disclosed by the above Publication has a
passage control unit between the pin fins and the inner side
surface of the passage that extends along flow direction of the
cooling medium in the passage. The passage control unit guides the
cooling medium flowing through the passage away from the inner side
surface of the passage so that the cooling medium flows toward the
region of the base in which the pin fins are formed. Therefore, the
cooling medium is prevented from flowing through the gap between
the inner side surface of the passage and the pin fins without
flowing through the region of the base, with the results that the
heating element is cooled further efficiently.
[0005] In the above-described cooling device wherein the passage
control unit is disposed in the passage of the base, a space needs
to be ensured in the passage for the passage control unit, which
makes the base larger.
[0006] In the cooling device, the provision of the passage control
unit reduces the sectional area of the passage of the base thereby
to reduce the gap between the passage control unit and the pin
fins, so that a pressure loss occurring when the cooling medium
flows through the passage is increased, which makes it difficult
for the cooling medium to flow through the passage smoothly.
[0007] The present invention is directed to providing a cooling
device that is reduced in size and allows a smooth flow of a
cooling medium.
SUMMARY OF THE INVENTION
[0008] In accordance with an aspect of the present invention, there
is provided a cooling device to which a heating element is
joinable. The cooling device includes a base, a plurality of first
groups of pin fins and a plurality of second groups of pin fins.
The base has a passage through which a cooling medium flows. The
first groups of pin fins are located in the passage and adjacent to
the heating element. The pin fins of each first group are arranged
in a width direction that is perpendicular to a flow direction in
which the cooling medium flows through the passage. One of the pin
fins of each first group that is the located closest to a side
surface of the base in the first group is a first outermost pin
fin. The second groups of pin fins are located in the passage and
adjacent to the heating element. The pin fins of each second group
are arranged in the width direction that is perpendicular to the
flow direction in which the cooling medium flows through the
passage. One of the pin fins of each second group that is located
closest to the side surface of the base in the second group is a
second outermost pin fin. The second groups and the first groups
are arranged alternately in the flow direction. The pin fins of the
second groups and the first groups are provided in a staggered
arrangement. The second outermost pin fin of each second group is
more distant from the side surface of the base than the first
outermost pin fin of each first group. Width between a side surface
of the second outermost pin fin of each second group and the side
surface of the base is the same as or larger than width between a
side surface of the pin fin of each first group that is adjacent to
the first outermost pin fin of the first group and the side surface
of the second outermost pin fin.
[0009] Other aspects and advantages of the invention will become
apparent from the following description, taken in conjunction with
the accompanying drawings, illustrating by way of example the
principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The invention together with objects and advantages thereof,
may best be understood by reference to the following description of
the presently preferred embodiments together with the accompanying
drawings in which:
[0011] FIG. 1 is an exploded perspective view showing a cooling
device according to an embodiment of the present invention;
[0012] FIG. 2 is a horizontal sectional view showing the cooling
device of FIG. 1;
[0013] FIG. 3 is an enlarged fragmentary view showing the cooling
device of FIG. 2;
[0014] FIG. 4 is a schematic view illustrating a cooling device of
a comparative example;
[0015] FIG. 5 is a schematic view illustrating the cooling device
of FIG. 1;
[0016] FIG. 6 is an enlarged fragmentary schematic view
illustrating the cooling device of FIG. 1;
[0017] FIG. 7A is a fragmentary sectional view showing a cooling
device according to a modification of the present invention;
and
[0018] FIG. 7B is a fragmentary sectional view showing a cooling
device according to another modification of the present
invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0019] The following will describe the cooling device according to
the embodiment of the present invention with reference to FIGS. 1
through 6. Referring to FIG. 1, the cooling device is designated by
reference numeral 10 and has a base 20. The base 20 includes a
first base member 21 and a second base member 22 joined to each
other. The members 21 and 22 are both made of aluminum and have
substantially the same shape. Each of the members 21 and 22 has a
rectangular outer plate 23, two sidewalls 25A that extend from the
respective two short sides of the outer plate 23, two sidewalls 25B
that extend from the respective two long sides of the outer plate
23, and a plate-like joint 26 that extends horizontally outward
from the ends of the sidewalls 25A and 25B.
[0020] The base 20 has therein an inner space S that serves as a
passage through which a cooling medium flows. A semiconductor
device 28 that serves as a heating element is joined to the outer
plate 23 of the first base member 21 via a rectangular insulating
base plate 27 at the outer surface of the outer plate 23 whose
inner surface faces the inner space S. More specifically, the
insulating base plate 27 is joined at the lower surface thereof to
the first base member 21 via a metal plate (not shown) that serves
as a joining layer. It is noted that the long-side direction of the
insulating base plate 27 corresponds to that of the first base
member 21. The semiconductor device 28 is mounted on the upper
surface of the insulating base plate 27 via a metal plate (not
shown) that serves as a wiring layer.
[0021] A rectangular support plate 32 is interposed between the
first base member 21 and the second base member 22 and supports a
plurality of pin fins 31 in the inner space S of the base 20. The
support plate 32 has substantially the same shape and size in
planar view as the outer profile of the joints 26 of the first and
second base members 21 and 22. The support plate 32 is held between
the joints 26 of the base members 21 and 22 so that the opposite
surfaces of the support plate 32 face the outer plates 23 of the
base members 21 and 22, respectively. The joint 26 of the first
base member 21, the joint 26 of the second base member 22 and the
support plate 32 are sealingly joined together by brazing. The
support plate 32 thus disposed in the cooling device separates the
inner space S into a first passage S1 (FIG. 2) and a second passage
S2 (FIG. 1).
[0022] The sidewalls 25A and the joint 26 of the first base member
21 have recesses 33A and 34A (refer to FIG. 2). The sidewalls 25A
and the joint 26 of the second base member 22 have also recesses
33B and 34B. With the joints 26 of the first and second base
members 21 and 22 joined in place to the support plate 32 on the
opposite surfaces thereof, the recesses 33A and 34A of the first
base member 21 allow the first passage S1 to communicate with the
outside of the base 20. Similarly, the recesses 33B and 34B of the
second base member 22 allow the second passage S2 to communicate
with the outside of the base 20.
[0023] A cylindrical inlet tube 41 is connected to the base members
21 and 22 at the recesses 33A and 33B thereof so that cooling
medium flows into the first and second passages S1 and S2 via the
openings formed by the recesses 33A and 33B, respectively. In
addition, a cylindrical outlet tube 42 is connected to the base
members 21 and 22 at the recesses 34A and 34B thereof so that
cooling medium flows out of the first and second passages S1 and S2
via the openings formed by the recesses 34A and 34B, respectively.
Thus, the cooling medium flows from the inlet tube 41 toward the
outlet tube 2 in the direction along the long side of the base
members 21 and 22.
[0024] Referring to FIG. 2, the pin fins 31 are formed on both of
the upper and lower surfaces of the support plate 32 in a staggered
arrangement in planar view thereby to form pin fin units 50. The
staggered arrangements of the pin fins 31 on the upper and lower
surfaces of the support plate 32 are the same. Specifically, the
pin fins 31 on each of the opposite surfaces of the support plate
32 in the illustrated embodiment (pin fins on one surface being
shown in the drawing) include seven rows of pin fins 31, the rows
being substantially equidistantly spaced in the direction along the
long side of the support plate 21 (or in the flow direction in
which the cooling medium flows through the inner space S). More
specifically, the seven rows include three first rows of pin fins,
each row including three first pin fins 31B arranged at a
predetermined spaced interval in the direction along the short side
of the support plate 32 and four second rows of pin fins, each row
including four second pin fins 31A arranged at the same spaced
interval in the same direction as the first pin fins 31B.
Furthermore, the first rows of the first pin fins 31B and the
second rows of the second pin fins 31A are arranged alternately in
the flow direction and the first and second pin fins 31B and 31A of
any two adjacent first and second rows are disposed in a staggered
arrangement, as clearly shown in FIG. 2.
[0025] As shown in FIGS. 1 and 2, all the pin fins 31 are
cylindrical in shape with the same length and diameter and extend
from the respective surfaces of the support plate 32. All the pin
fins 31 that extend upward from the upper surface of the support
plate 32 are joined at the upper ends thereof to the outer plate 23
of the first base member 21. All the pin fins 31 that extend
downward from the lower surface of the support plate 32 are joined
at the lower ends thereof to the outer plate 23 of the second base
member 22.
[0026] Each of the inner side surfaces of the sidewalls 25B of the
base members 21 and 22 that extend along the flow direction of
cooling medium are formed with three projections 60 projecting
inward from the inner side surface and spaced at the same interval
as the pin fins 31 in the flow direction, as shown in FIGS. 2 and
3. As seen in FIG. 2, each projection 60 has the shape of a segment
of a circle that is the same as the circle of the cylindrical pin
fin 31 in horizontal section of the base 20 (the segment of the
circle is smaller than the semicircle). The projection 60 is formed
so that the vertical section thereof is reduced gradually toward
the end. The projection 60 is formed so that any normal to the
outer circumferential surface of the projection 60 is directed
inward of the inner space S of the base members 21 and 22 away from
the sidewall 25B.
[0027] With the support plate 32 held between the joints 26 of the
base members 21 and 22, the projections 60 and the first pin fins
31B are arranged along three parallel phantom lines extending in
the direction along the short side of the support plate 32 (or in
width direction perpendicular to the flow direction). In the
present embodiment, the first pin fins 31B and the projections 60
that are arranged along three parallel phantom lines extending in
the width direction form first groups of pin fins. In this case,
the projections 60 that form part of the sidewalls 25B of the base
members 21 and 22 will be regarded as the first outermost pin fins
of the first groups of pin fins.
[0028] In the present embodiment, four rows of second pin fins 31A
arranged along the width direction across the flow direction form
second groups of pin fins. The second pin fins 31A that are located
closest to the opposite sidewalls 25B of the base members 21 and 22
in each of the second groups of pin fins are regarded as the second
outermost pin fins 31A1. Unlike the first outermost pin fins, the
second outermost pin fins 31A1 are separated from the sidewalls 25B
of the base members 21 and 22. In this respect, the projections 60
are closer to the side surfaces of the sidewalls 25B that extends
along the flow direction of the cooling medium in the inner space S
than the second outermost pin fins 31A1. That is, the second
outermost pin fins 31A1 are more distant from the side surfaces of
the sidewalls 25B than the projections 60.
[0029] It is noted that the distance L1 or the shortest distance
between the outer circumferential surface (side surface) of the
second outermost pin fin 31A1 and the inner side surface of the
adjacent sidewall 25B of each of the base members 21 and 22 is
larger than the distance L2 or the shortest distance between the
outer circumferential surface (side surface) of the first pin fin
31B that is located closest to the projection 60 in the first group
of pin fins and the outer circumferential surface (side surface) of
its adjacent second outermost pin fin 31A1. Therefore, the width W1
between the outer circumferential surface of the second outermost
pin fin 31A1 and the inner side surface of the adjacent sidewall
25B of each of the base members 21 and 22 is larger than the width
W2 between the outer circumferential surface of the first pin fin
31B that is located closest to the projection 60 in the first group
of pin fins and the outer circumferential surface (side surface) of
its adjacent second outermost pin fin 31A1.
[0030] The distance L3 or the shortest distance between the outer
circumferential surface of the projection 60 and the outer
circumferential surface of its adjacent second outermost pin fin
31A1 is substantially the same as the distance L2. Therefore, the
width W3 between the outer circumferential surface of the
projection 60 and the outer circumferential surface of its adjacent
second outermost pin fin 31A1 is substantially the same as the
width W2.
[0031] The following will describe the operation of the
above-described cooling device 10. Referring to FIG. 4 illustrating
the manner in which the cooling medium flows in the cooling device
of a comparative example that is designated by reference numeral
110, the cooling medium flows not only through the region P1 of the
inner space S in which pin fins 131 are formed as indicated by
solid arrows in FIG. 4, but part of the cooling medium flows
through the region P2 of the inner space S between the outermost
rows of pin fins 131 and the inner side surfaces of the base 120 as
indicated by dashed-dotted arrows in FIG. 4. The cooling medium
flowing through the region P2 contributes very little to heat
radiation from the base 120 through the pin fins 131, so that
efficient cooling of the semiconductor device 28 joined to the base
120 cannot be accomplished.
[0032] Referring to FIG. 5 illustrating the manner in which the
cooling medium flows in the cooling device 10 of the present
embodiment, on the other hand, the width W1 between the outer
circumferential surface of the second outermost pin fin 31A1 and
the inner side surface of its adjacent sidewall 25B in the cooling
device 10 of the present embodiment is smaller than the width W11
between the sidewall 125B and the pin fin 131 adjacent to the
sidewall 125B in the cooling device 110 of the comparative example
shown in FIG. 4. Thus, the cooling medium steadily flows through
the region P1 of the inner space S as indicated by solid arrows in
FIG. 5. Therefore, the cooling medium efficiently contributes
greatly to heat radiation from the base 20 through the pin fins 31
thereby to efficiently cool the semiconductor device 28 joined to
the base 20.
[0033] The width W4 of the inner space S of the base 20 of the
cooling device 10 in the present embodiment may be smaller than the
width W14 of the inner space S of the base 120 of the cooling
device 110. Therefore, the dimension of the base 20 in the width
direction perpendicular to the flow direction of the cooling medium
is reduced and hence the base 20 is made smaller.
[0034] In the present embodiment wherein the inner space S of the
base 20 has the width W4, no passage of the cooling medium flowing
through the inner space S of the base 20 has a width that is
reduced compared to the width W2. Therefore, the pressure loss
occurring when the cooling medium flows through the inner space S
of the base 20 is prevented from being increased.
[0035] Referring to FIG. 6, the cooling medium flowing along the
sidewall 25B of the base 20 is guided inward away from the sidewall
25B by the projection 60, as indicated by arrowed line. Therefore,
the cooling medium is guided to flow toward the region P1 of the
inner space S.
[0036] The width W3 is substantially the same as the width W2. In
the present embodiment wherein the projection 60 is formed on the
sidewall 25B of the base 20, no passage of the cooling medium
flowing through the inner space S of the base 20 has a width that
is reduced compared to the width W2. Therefore, the pressure loss
occurring when the cooling medium flows through the inner space S
of the base 20 is prevented from being increased.
[0037] The above-described embodiment has the following
advantageous effects.
[0038] (1) In the present embodiment according to the present
invention wherein the width W1 between the outer circumferential
surface of the second outermost pin fin 31A1 and the inner side
surface of its adjacent sidewall 25B of each of the base members 21
and 22 is larger than the width W2 between the outer
circumferential surface of the first pin fin 31B adjacent to the
projection 60 in the first group of pin fins and the outer
circumferential surface of its adjacent second outermost pin fin
31A1, the sidewall 25B of the base members 21 and 22 is located
close to the pin fins 31 while a sufficient space or distance for
the width W1 between the second outermost pin fin 31A1 and its
adjacent sidewall 25B of the base members 21 and 22 is ensured.
Thus, the cooling medium can steadily flow through the region P1 of
the inner space S and the pressure loss occurring when the cooling
medium flows through the inner space S of the base 20 is prevented
from being increased. Therefore, such smooth flow of the cooling
medium through the region P1 of the inner space S helps to cool the
semiconductor device 28 efficiently. In addition, in the present
embodiment wherein the inner side surface of the base 20 is located
close to the pin fins 31, the width dimension of the inner space S
is reduced thereby to reduce the size of the base 20 having the
inner space S and hence the size of the cooling device 10.
[0039] (2) The width W3 between the outer circumferential surface
of the projection 60 and the outer circumferential surface of its
adjacent second outermost pin fin 31A1 is substantially the same as
the width W2 between the outer circumferential surface of the first
pin fin 31B adjacent to the projection 60 in the first group of pin
fins and the outer circumferential surface of its adjacent second
outermost pin fin 31A1. In addition, the width W1 between the outer
circumferential surface of the second outermost pin fin 31A1 and
the inner side surface of its adjacent sidewall 25B of each of the
base members 21 and 22 is larger than the width W3 between the
outer circumferential surface of the projection 60 and the outer
circumferential surface of its adjacent second outermost pin fin
31A1. Thus, the width W1 is larger than the width W2. Since a
sufficient space or distance for the width W1 is ensured, the
pressure loss occurring when the cooling medium flows through the
inner space S of the base 20 is prevented from being increased.
[0040] (3) In the present embodiment, the projection 60 formed
projecting into the inner space S from the sidewall 25B that
extends along the flow direction of the cooling medium in the inner
space S guides the cooling medium toward the region P1 of the inner
space S, thereby to allow the cooling medium to flow further
steadily through the region P1 of the inner space S.
[0041] (4) In the present embodiment wherein the projection 60 is
formed so that the vertical section thereof is reduced gradually
toward its end, even if the distance L3 is set relatively small, a
sufficient space or distance for the width between the outer
circumferential surface of the projection 60 and the outer
circumferential surface of its adjacent second outermost pin fin
31A1 is ensured. Therefore, the pressure loss occurring when the
cooling medium flows through the space between the projection 60
and its adjacent second outermost pin fin 31A1 is further
reduced.
[0042] (5) The base 20 is reinforced by the pin fins 31 thereby to
increase its rigidity. Therefore, the reinforced base 20 restricts
warping of the base 20 occurring due to the difference in the
linear thermal expansion coefficient between the insulating base
plate 27 and the base 20.
[0043] The present embodiment may be practiced as exemplified
below.
[0044] Referring to FIG. 7A, the projection 60 may be formed in the
shape of a semicylinder having a semicircle of a circle that is the
same as that of the cylindrical pin fin 31 in horizontal section of
the base 20.
[0045] Referring to FIG. 7B, the projection 60 may be formed in the
shape of a partial cylinder having a partial circle of a circle
that is the same as that of the cylindrical pin fin 31 and being
larger in horizontal section than the semicylinder of FIG. 7A.
[0046] In the above-described embodiment, it may be so configured
that the width W1 between the outer circumferential surface of the
second outermost pin fin 31A1 and the inner side surface of its
adjacent sidewall 25B of each of the base members 21 and 22 is the
same as the width W2 between the outer circumferential surface of
the first pin fin 31B adjacent to the projection 60 in the first
group of pin fins and the outer circumferential surface of its
adjacent second outermost pin fin 31A1.
[0047] In the above-described embodiment, projections similar in
shape to the projections 60 shown in FIGS. 6, 7A and 7B may be
formed so as to extend from the opposite surfaces of the support
plate 32.
[0048] In the above-described embodiment, the projections such as
the projections 60 shown in FIGS. 6, 7A and 7B may have the shape
of a partial cylinder having a partial circle of a circle having a
diameter that is different from that of the cylindrical pin fin
31.
[0049] In the above-described embodiment, the projections 60 of
FIGS. 6, 7A and 7B need not to be formed in a partial cylindrical
shape. The projection 60 may be formed to have a spherical outer
surface. In such a structure, the flow direction of the cooling
medium passing through the space between the projection 60 and its
adjacent pin fin 31 is changed to the direction that is normal to
the spherical outer surface of the projection 60. Therefore, the
cooling medium flowing in the inner space S of the base 20 is
efficiently guided toward the region of the inner space S in which
the pin fins 31 are formed.
[0050] In the above-described embodiment, the pin fin 31 may be
replaced by a pin of a polygonal column shape such as triangular
prism or quadrangular prism.
[0051] In the above-described embodiment, the pin fins 31 may be
arranged in a grid pattern in a planar view.
[0052] In the above-described embodiment, the number of pin fins 31
supported by the support plate 32 may be changed as desired.
[0053] In the above-described embodiment, the support plate 32 may
be modified so as to have the pin fins 31 only on one side thereof
without separating the inner space S into the upper and lower
spaces.
* * * * *