U.S. patent application number 12/851184 was filed with the patent office on 2011-02-10 for cylinder barrel inside surface treatment apparatus and method.
This patent application is currently assigned to HONDA MOTOR CO., LTD.. Invention is credited to Hitoshi Karasawa, Hiroyuki NARUSE, Yoshimitsu Ogawa, Ryotaro Takada.
Application Number | 20110031219 12/851184 |
Document ID | / |
Family ID | 43534048 |
Filed Date | 2011-02-10 |
United States Patent
Application |
20110031219 |
Kind Code |
A1 |
NARUSE; Hiroyuki ; et
al. |
February 10, 2011 |
CYLINDER BARREL INSIDE SURFACE TREATMENT APPARATUS AND METHOD
Abstract
A cylinder barrel inside surface treatment apparatus for
providing a uniform treatment finish is disclosed. The treatment
apparatus includes a pallet on which a cylinder block is placed
with a gasket surface faced upward. A top opening of a cylinder
barrel of the cylinder block is covered by a cover member having a
concave portion communicating with the top opening. A nozzle having
treatment solution spray holes is attached to the cover member. The
treatment solution is sprayed toward a wall of the concave portion
from the treatment solution spray holes and flows along the wall
from a top end to a bottom end of the cylinder barrel inside
surface.
Inventors: |
NARUSE; Hiroyuki; (Tochigi,
JP) ; Karasawa; Hitoshi; (Tochigi, JP) ;
Takada; Ryotaro; (Tochigi, JP) ; Ogawa;
Yoshimitsu; (Tochigi, JP) |
Correspondence
Address: |
ARENT FOX LLP
1050 CONNECTICUT AVENUE, N.W., SUITE 400
WASHINGTON
DC
20036
US
|
Assignee: |
HONDA MOTOR CO., LTD.
Tokyo
JP
|
Family ID: |
43534048 |
Appl. No.: |
12/851184 |
Filed: |
August 5, 2010 |
Current U.S.
Class: |
216/100 ;
156/345.51 |
Current CPC
Class: |
C25D 17/02 20130101;
C23F 1/08 20130101; C25D 7/04 20130101; C25D 5/34 20130101 |
Class at
Publication: |
216/100 ;
156/345.51 |
International
Class: |
C23F 1/02 20060101
C23F001/02; C23F 1/08 20060101 C23F001/08 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 7, 2009 |
JP |
P2009-184933 |
Claims
1. A cylinder barrel inside surface treatment apparatus for causing
a treatment solution to come into contact with an inside surface of
a cylinder barrel provided to a cylinder block of an internal
combustion engine and treating the cylinder barrel inside surface,
the apparatus comprising: a pallet for supporting the cylinder
block with a gasket surface of the cylinder block faced upward, and
closing off a bottom opening of the cylinder barrel; a first
drainage passage provided to the pallet for discharging a portion
of the treatment solution accumulated in the cylinder barrel; a
cover member placed on the gasket surface for covering a top
opening of the cylinder barrel and having at a bottom thereof a
concave portion communicating with the top opening of the cylinder
barrel; a nozzle inserted from above downward into and attached to
the cover member and having treatment solution spray holes for
spraying the treatment solution toward a wall of the concave
portion so as to feed the treatment solution to the inside surface
of the cylinder barrel along the concave portion wall; and a second
drainage passage provided in the cover member for discharging the
remaining treatment solution accumulated in the cylinder
barrel.
2. The treatment apparatus of claim 1, wherein the treatment
solution spray holes are positioned upwardly of a top edge of the
cylinder block.
3. The treatment apparatus of claim 1, wherein the pallet has on a
top surface thereof a positioning pin designed to be engaged in a
hole formed in the cylinder block.
4. A cylinder barrel inside surface treatment method for causing a
treatment solution to come into contact with an inside surface of a
cylinder barrel provided to a cylinder block of an internal
combustion engine and treating the cylinder barrel inside surface,
the method comprising the steps of: placing the cylinder block,
with a gasket surface thereof faced upward, on a pallet for closing
off a bottom opening of the cylinder barrel; covering, while
inserting a treatment solution feeding nozzle into a top opening of
the cylinder barrel, the cylinder barrel top opening with a cover
member having at a bottom thereof a concave portion communicating
with the cylinder barrel top opening; spraying the treatment
solution toward a wall of the concave portion from treatment
solution spray holes provided to the nozzle so as to feed the
treatment solution along the wall of the concave portion to the
cylinder barrel inside surface; and discharging a portion of the
treatment solution accumulated in the cylinder barrel from a first
drainage passage provided to the pallet and discharging a remaining
part of the treatment solution accumulated in the cylinder barrel
from a second drainage passage provided to the cover member.
5. The treatment method of claim 4, wherein the treatment solution
is fed from a top end to a bottom end of the inside surface of the
cylinder barrel.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to an improvement in a
technique for causing a treatment solution to come into contact
with an inside surface of a cylinder barrel of an engine and
treating the cylinder barrel inside surface.
BACKGROUND OF THE INVENTION
[0002] An inside surface of a cylinder barrel of an engine is
exposed to friction from a piston ring and high heat from
combustion of fuel, thus requiring the surface to be strong. A
surface treatment is effective for increasing the durability of the
surface. With a plating treatment, which is one type of surface
treatment, any surface fouling or the like is preferably removed
prior to the plating treatment. The process of removing fouling
substances before the surface treatment is referred to as
pre-treatment.
[0003] An example of a plating pre-treatment will now be described
with reference to FIG. 9 hereof.
[0004] As shown in FIG. 9, an etching treatment, an acid activation
treatment, a first zincate conversion treatment, a dissolution
activation treatment, and a second zincate conversion treatment are
performed in the pre-treatment. The etching treatment alone is made
up of a plurality of steps including chemical treatment using a
treatment solution, primary and secondary rinses for cleaning, and
an idler or the like to prevent drying. A specific example of the
chemical treatment step as one of these steps is disclosed, e.g.,
in Japanese Patent Application Laid-Open Publication No.
2008-214730 (JP-A 2008-214730).
[0005] Reference is made next to FIG. 10 showing the chemical
treatment apparatus disclosed in JP-A 2008-214730.
[0006] As shown in FIG. 10, a cylinder block 101 is mounted on a
pallet 104 provided with a member 103 for closing off a bottom
opening, and the bottom opening of the cylinder block 101 is closed
off. The pallet 104 is disposed above a pan 105, and a lid 107
provided with a nozzle 106 is moved as indicated by the arrow (1)
to close off the top opening of the cylinder block 101.
[0007] A treatment solution is fed to the nozzle 106 from a
treatment solution feed channel 108 as indicated by arrow (2).
[0008] The supplied treatment solution is sprayed at the bottom
portion of a cylinder barrel 110 from a treatment solution spray
hole 109 as indicated by the arrow (3), and the treatment solution
ascends while coming in contact with an inside surface of the
cylinder barrel 110, as indicated by arrow (4).
[0009] The treatment solution in the cylinder barrel 110 is
discharged mainly from a first drainage passage 111 provided to the
pallet 104, as indicated by arrow (5), and the remainder of the
treatment solution is discharged from a second drainage passage 112
provided to the lid 107, as indicated by arrow (6).
[0010] However, cylinder blocks are configured in a variety of
ways. The inventors therefore applied the same etching treatment to
a cylinder block configured without a crankcase part 102.
[0011] As shown in FIG. 11, a cylinder block 114 is mounted on a
pallet 115 so that a gasket surface 113 is facing upward. A step
portion 117 of the cylinder block 114 is sealed by a seal member
116. A top opening 119 of a cylinder barrel 118 is covered by a
cover member 121 having a concave portion 120 leading to the top
opening 119 of the cylinder barrel 118. A nozzle 122 for feeding
treatment solution to the inside surface of the cylinder barrel 118
is provided to the cover member 121, and treatment solution spray
holes 123 for spraying treatment solution are provided at the
bottom of the nozzle 122.
[0012] The following results were obtained when the treatment
solution was fed in the same manner as shown in FIG. 9 in the
cylinder block 114. Reference characters A, B, and C in FIG. 11
indicate top, middle, and bottom measurement points, respectively,
of the inside surface of the cylinder barrel 118.
[0013] When the high-temperature treatment solution is sprayed from
treatment solution spray holes 123, 123, the treatment solution
accumulates on the pallet 115 and ascends the inside of the
cylinder barrel 118 to reach the concave portion 120. As a result,
point C increases in temperature first, then point B, and lastly
point A. Moreover, since heat retained by the treatment solution is
absorbed by the cylinder barrel 118 before the treatment solution
reaches point A, the temperature decreases. As a result, a
temperature difference having a maximum T1 of as much as 25.degree.
C. occurs between the temperature increase curve of point A and the
temperature increase curve of point C, as shown in FIG. 12.
[0014] The surface of the cylinder barrel is etched (corroded) by
the treatment solution, but the amount of etching varies according
to the temperature. A temperature difference having a maximum T1 of
25.degree. C. is expected to affect the etching treatment. The
amount of etching at each of the points A, B, and C was therefore
examined.
[0015] As shown in FIG. 13A, the etching amount x1 was adequate at
points B and C, but was low at point A.
[0016] When the etching amount is low, i.e., inadequate, adhesion
of the plating is expected to decrease. The plating adhesion was
therefore studied at each of the points A, B, and C.
[0017] When plating was applied to the pre-treated cylinder barrel,
it was apparent that the peel width y1 of the plating was small at
points B and C and large at point A, as shown in FIG. 13B. This is
because a temperature difference on the inside surface of the
cylinder barrel causes the treatment to be unevenly performed.
Specifically, a technique is needed for treating the inside surface
of a cylinder barrel, whereby the surface treatment can be made
uniform.
SUMMARY OF THE INVENTION
[0018] It is therefore an object of the present invention to
provide a technique for treating the inside surface of a cylinder
barrel, whereby the surface treatment can be made uniform.
[0019] According to an aspect of the present invention, there is
provided a cylinder barrel inside surface treatment apparatus for
causing a treatment solution to come into contact with an inside
surface of a cylinder barrel provided to a cylinder block of an
internal combustion engine and treating the cylinder barrel inside
surface, which apparatus comprises: a pallet for supporting the
cylinder block with a gasket surface of the cylinder block faced
upward, and closing off a bottom opening of the cylinder barrel; a
first drainage passage provided to the pallet for discharging a
portion of the treatment solution accumulated in the cylinder
barrel; a cover member placed on the gasket surface for covering a
top opening of the cylinder barrel and having at a bottom thereof a
concave portion communicating with the top opening of the cylinder
barrel; a nozzle inserted from above downward into and attached to
the cover member and having treatment solution spray holes for
spraying the treatment solution toward a wall of the concave
portion so as to feed the treatment solution to the inside surface
of the cylinder barrel along the concave portion wall; and a second
drainage passage provided in the cover member for discharging the
remaining treatment solution accumulated in the cylinder
barrel.
[0020] In the thus-arranged apparatus, since the treatment solution
is sprayed in the concave portion rather than being sprayed
directly onto the inside surface of the cylinder barrel, it is
possible to prevent reaction that is biased toward the portion
directly contacted by the treatment solution, so that the reaction
can be made uniform. As a result, the inside surface of the
cylinder barrel will be uniformly etched, allowing plating adhesion
to be improved.
[0021] Preferably, the treatment solution spray holes are
positioned upwardly of a top edge of the cylinder block. Since the
treatment solution flows along the inside surface of the cylinder
barrel from the top end to the bottom end thereof, the inside
surface is uniformly etched.
[0022] Desirably, the pallet has on a top surface thereof a
positioning pin adapted to be engaged in a hole formed in the
cylinder block. The cylinder block is thereby always set on the
pallet in a fixed position.
[0023] According to another aspect of the present invention, there
is provided a cylinder barrel inside surface treatment method for
causing a treatment solution to come into contact with an inside
surface of a cylinder barrel provided to a cylinder block of an
internal combustion engine and treating the cylinder barrel inside
surface, which method comprises the steps of: placing the cylinder
block, with a gasket surface thereof faced upward, on a pallet for
closing off a bottom opening of the cylinder barrel; covering,
while inserting a treatment solution feeding nozzle into a top
opening of the cylinder barrel, the cylinder barrel top opening
with a cover member having at a bottom thereof a concave portion
communicating with the cylinder barrel top opening; spraying the
treatment solution toward a wall of the concave portion from
treatment solution spray holes provided to the nozzle so as to feed
the treatment solution along the wall of the concave portion to the
cylinder barrel inside surface; and discharging a portion of the
treatment solution accumulated in the cylinder barrel from a first
drainage passage provided to the pallet and discharging a remaining
part of the treatment solution accumulated in the cylinder barrel
from a second drainage passage provided to the cover member.
[0024] By introducing the treatment solution from above the
cylinder barrel and causing the liquid surface to rise back from
below to circulate the treatment solution, the difference in
temperature between the top and the bottom of the inside surface of
the cylinder barrel can be reduced, and the surface treatment can
be made uniform. As a result, the inside surface of the cylinder
barrel is uniformly etched, and plating adhesion can therefore be
improved.
[0025] It is preferred that the treatment solution be fed from a
top end to a bottom end of the inside surface of the cylinder
barrel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Certain preferred embodiments of the present invention will
be described in detail below, by way of example only, with
reference to the accompanying drawings, in which:
[0027] FIG. 1 is a side view showing an apparatus for treating an
inside surface of a cylinder barrel, according to an embodiment of
the present invention;
[0028] FIG. 2 is a sectional view showing a surface treatment unit
of FIG. 1;
[0029] FIGS. 3A and 3B are cross-sectional views illustrative of a
process for positioning a cylinder block;
[0030] FIGS. 4A to 4C are cross-sectional views illustrative of a
process for treating the surface of the cylinder block;
[0031] FIG. 5 is a graph showing the change in temperature of the
inside surface of the cylinder barrel of FIG. 2;
[0032] FIG. 6 is a graph showing for comparison the temperature
differences of the inside surface of the cylinder barrel in the
present embodiment and the prior art;
[0033] FIG. 7 is a graph showing an etching amount in the present
embodiment;
[0034] FIG. 8 is a graph showing plating adhesion in the present
embodiment;
[0035] FIG. 9 is a view showing a pre-treatment process in
conventional plating;
[0036] FIG. 10 is a schematic view illustrating a conventional
surface treatment apparatus;
[0037] FIG. 11 is a cross-sectional view showing the conventional
surface treatment apparatus as used in a cylinder block having no
crankcase part;
[0038] FIG. 12 is a graph showing changes in temperature of the
inside surface of a cylinder barrel during conventional surface
treatment; and
[0039] FIGS. 13A and 13B are graphs showing etching amounts and
plating adhesion in the conventional surface treatment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0040] As shown in FIG. 1, an apparatus 10 for treating an inside
surface of a cylinder barrel according to the present embodiment is
provided with a base 12 having adjusters 11; lower columns 13
provided upright on the base 12; a middle support member 15
provided on the top ends of the lower columns 13; a pan 16 for
collecting a treatment solution, the pan 16 being supported by the
middle support member 15; a treatment solution discharge tube 14
for leading the treatment solution collected in the pan 16 to the
outside; an enclosure member 17 provided above the pan 16; a
surface treatment unit 20 provided on the middle support member 15
and surrounded by the enclosure member 17; a drainage tube 21 for
directing drainage from the top portion of the surface treatment
unit 20, the drainage tube 21 being provided to the surface
treatment unit 20; a treatment solution detector 22 for monitoring
the drainage tube 21; middle columns 23 provided upright on the
middle support member 15; an upper support member 24 provided on
the top ends of the middle columns 23; upper columns 25 provided
upright on the upper support member 24; and a top panel 26 provided
on the top ends of the upper columns 25.
[0041] The surface treatment unit 20, which shall be described in
detail hereinafter, is provided with a pallet 31 for supporting a
cylinder block 27 subjected to a surface treatment; a cover member
32 for covering a top portion of the cylinder block 27; and a
second drainage passage 33 provided to the cover member 32 so as to
discharge a portion of the treatment solution.
[0042] The surface treatment apparatus 10 for the inside surface of
a cylinder barrel is also provided with a raising/lowering cylinder
35 for raising and lowering the cover member 32 via a
raising/lowering rod 34, the raising/lowering cylinder 35 being
provided to the top panel 26; a pivoting part 37 provided so as to
be able to pivot about a rotary shaft 36 at a bottom end of the
raising/lowering rod 34; and a pivot cylinder 41 for causing the
pivoting part 37 to pivot via an advancing/retreating rod 38, the
pivot cylinder 41 being provided to the lower portion of the
raising/lowering rod 34.
[0043] The relevant parts of the surface treatment apparatus 10 for
the inside surface of a cylinder barrel will next be described.
[0044] As shown in FIG. 2, the surface treatment unit 20 is
composed of a pallet 31 for supporting the cylinder block 27 so
that a gasket surface 42 of the cylinder block 27 faces upward, and
closing off a bottom opening 44 of a cylinder barrel 43; a first
drainage passage 45 provided to the pallet 31 so as to discharge a
portion of the treatment solution accumulated in the cylinder
barrel 43; a step portion seal member 47 provided to the pallet 31
so as to seal a step portion 46 of the cylinder block 27; a
positioning pin 51 provided to the pallet 31 so as to position a
hole 48 of the cylinder block 27; a cover member 32 mounted on the
gasket surface 42 so as to cover a top opening 52 of the cylinder
barrel 43, the cover member 32 having a concave portion 53 leading
to the top opening 52 of the cylinder barrel 43; a gasket surface
seal member 54 provided to a bottom end of the cover member 32 so
as to seal the gasket surface 42; a nozzle 57 for feeding treatment
solution to the inside surface of the cylinder barrel 43 along a
wall 55 of the concave portion 53, the nozzle 57 being inserted
downward from the top of the cover member 32 and attached to the
cover member 32, and having treatment solution spray holes 56 for
spraying the treatment solution toward the wall 55 of the concave
portion 53; a treatment solution feed channel 58 for feeding the
treatment solution to the nozzle 57; and the second drainage
passage 33 provided to the cover member 32 so as to discharge the
remaining treatment solution accumulated in the cylinder barrel
43.
[0045] The treatment solution spray holes 56 formed in the nozzle
57 are positioned higher than the top opening 52 of the cylinder
block 27. The treatment solution therefore flows uniformly from the
top end of the inside surface of the cylinder barrel 43 to the
bottom end thereof. The treatment solution spray holes 56 are
composed of a plurality of holes, and are preferably in a radial
arrangement in the radial direction of the nozzle 57 from the
treatment solution feed channel 58, but may also be in a cross
arrangement.
[0046] An operation of the surface treatment apparatus 10 described
above will next be described based on FIGS. 3A through 4C.
[0047] FIGS. 3A and 3B show the process of positioning the cylinder
block 27 in the surface treatment apparatus 10.
[0048] FIG. 3A shows the process of mounting the cylinder block 27
on the pallet 31. The cylinder block 27 is mounted on the pallet 31
as indicated by the arrow (7) so that the gasket surface 42 of the
cylinder block 27 faces upward, the pallet 31 closing off the
bottom opening 44 of the cylinder barrel 43. The positioning pin 51
is inserted in the hole 48, and the cylinder block 27 is thereby
properly positioned on the pallet 31 at all times.
[0049] FIG. 3B shows the process of covering the top opening 52 of
the cylinder block 27. The cover member 32 is moved as indicated by
the arrow (8), and covers the top opening 52 of the cylinder barrel
43 while the nozzle 57 is inserted in the top opening 52 of the
cylinder barrel 43.
[0050] FIG. 4A shows the process of feeding treatment solution to
the nozzle 57. The treatment solution is fed to the nozzle 57 via
the treatment solution feed channel 58, as indicated by the arrow
(9). The treatment solution fed to the nozzle 57 sprays toward the
wall 55 of the concave portion 53 from the treatment solution spray
holes 56. The treatment solution is fed to the inside surface of
the cylinder barrel 43 along the wall 55 of the concave portion 53,
as indicated by the arrows (10).
[0051] FIG. 4B shows the process whereby the treatment solution is
discharged from the first drainage passage 45. A portion of the
treatment solution accumulated in the cylinder barrel 43 is
discharged from the first drainage passage 45, as indicated by the
arrow (11). The amount of treatment solution fed is greater than
the amount discharged from the first drainage passage 45. The
treatment solution therefore accumulates in the cylinder barrel 43,
as indicated by the arrows (12). The nozzle 57 extends downward
past the cylinder barrel 43, and the volume of the space formed by
the inside surface of the cylinder barrel 43 and the outside
surface of the nozzle 57 is thereby reduced. The ascent of the
treatment solution is therefore accelerated, and the number of
steps involved in the treatment can be reduced.
[0052] FIG. 4C shows the process whereby the treatment solution is
discharged from the second drainage passage 33. The remainder of
the treatment solution accumulated in the cylinder barrel 43 is
discharged from the second drainage passage 33, as indicated by the
arrow (13). Monitoring the drainage through the use of the
treatment solution detector 22 (FIG. 1) enables the surface
treatment to be reliably performed.
[0053] The inventors investigated the change in temperature at
points A, B, and C shown in FIG. 2, and the obtained results will
be described using FIG. 5.
[0054] As shown in FIG. 5, the temperature immediately increased
when the high-temperature treatment solution was fed at points B
and C in the middle and lower portions of the cylinder barrel 43.
The results also showed that the temperature increase was also
rapid at the upper point A as compared with the prior art example
shown in FIG. 12. This is because the retained heat of the
treatment solution is transferred first to point A by the
high-temperature treatment solution being fed from above the inside
surface of the cylinder barrel 43, and the first temperature
increase thus occurs at point A. The reference symbol T2 refers to
the maximum temperature difference.
[0055] The temperature difference in the present embodiment shown
in FIG. 2 and the temperature difference in the prior art example
shown in FIG. 10 were then compared. The results of this comparison
are described using FIG. 6.
[0056] As shown in FIG. 6, the maximum temperature difference T1 in
the prior art example was 25.degree. C., whereas the maximum
temperature difference T2 in the present embodiment was 12.degree.
C. At the time immediately after the feeding of the treatment
solution started, the temperature difference between different
positions on the inside surface of the cylinder barrel in the
present embodiment was 15.degree. C. or less; i.e., small. It is
apparent that the temperature of the inside surface of the cylinder
barrel is more uniform in the present embodiment than in the prior
art example.
[0057] Reducing the temperature difference to 15.degree. C. or less
is also expected to minimize any effect on the etching treatment.
The amount of etching at each of the points A, B, and C was
therefore examined. The results are described using FIG. 7.
[0058] As shown in FIG. 7, the etching amount x2 was 2.5 .mu.m or
more at all of points A, B, and C; and was adequate. The plating
adhesion was expected to improve when the etching amount was
adequate. The plating adhesion at each of the points A, B, and C
was therefore examined. The results are described using FIG. 8.
[0059] As shown in FIG. 8, when the pre-treated cylinder barrel was
plated, the peel width y2 of the plating was small at all of the
points A, B, and C. This indicates that the absence of large
temperature differences on the inside surface of the cylinder
barrel allows the treatment to be evenly performed.
[0060] An example was described in the embodiment in which the
technique for treating a cylinder barrel surface according to the
present invention was applied to pre-treatment for plating, but a
pre-treatment for plating is not given by way of limitation; the
invention may be applied to another surface treatment process
provided that the surface treatment is performed on an inside
surface of a cylinder barrel.
[0061] The technique for treating an inside surface of a cylinder
barrel according to the present invention can be used in a plating
pre-treating of an inside surface of a cylinder barrel.
[0062] Obviously, various minor changes and modifications of the
present invention are possible in light of the above teaching. It
is therefore to be understood that within the scope of the appended
claims the invention may be practiced otherwise than as
specifically described.
* * * * *