U.S. patent application number 14/492690 was filed with the patent office on 2015-01-08 for doorbelt molding for vehicle and method for manufacturing doorbelt molding.
The applicant listed for this patent is Hyundai Motor Company, Kia Motors Corporation. Invention is credited to Chul Hong Bae, Chang Yeol Yoo, Kwang Min Yoon.
Application Number | 20150007503 14/492690 |
Document ID | / |
Family ID | 50098452 |
Filed Date | 2015-01-08 |
United States Patent
Application |
20150007503 |
Kind Code |
A1 |
Bae; Chul Hong ; et
al. |
January 8, 2015 |
DOORBELT MOLDING FOR VEHICLE AND METHOD FOR MANUFACTURING DOORBELT
MOLDING
Abstract
The present invention provides a method for manufacturing the
doorbelt molding including: forming an anodized layer on a surface
of an aluminum alloy plate by performing an anodizing treatment on
the aluminum alloy plate; forming a clear coating layer on the
anodized layer by performing a clear coating treatment on the
aluminum alloy plate on which the anodized layer is formed; molding
a sectional shape of an outer frame by roll-forming the aluminum
alloy plate over which the anodized layer and the clear coating
layer are formed; forming a molding intermediate member in which
the outer frame and an inner molding are integrally formed by
integrally injection-molding a synthetic resin into the outer frame
formed by the roll-forming, wherein the synthetic resin is a
material of the inner molding; bending and cutting the molding
intermediate member to manufacture the doorbelt molding.
Inventors: |
Bae; Chul Hong; (Suwon,
KR) ; Yoo; Chang Yeol; (Suwon, KR) ; Yoon;
Kwang Min; (Suwon, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hyundai Motor Company
Kia Motors Corporation |
Seoul
Seoul |
|
KR
KR |
|
|
Family ID: |
50098452 |
Appl. No.: |
14/492690 |
Filed: |
September 22, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13688614 |
Nov 29, 2012 |
8869375 |
|
|
14492690 |
|
|
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Current U.S.
Class: |
49/475.1 |
Current CPC
Class: |
Y10T 29/49982 20150115;
Y10T 29/49885 20150115; Y10T 29/4998 20150115; B60J 10/75 20160201;
B21B 1/00 20130101; Y10T 29/49888 20150115; B29C 41/22 20130101;
C25D 11/02 20130101; C25D 11/18 20130101; C25D 11/06 20130101; C25D
11/04 20130101; C25D 11/24 20130101 |
Class at
Publication: |
49/475.1 |
International
Class: |
B60J 10/04 20060101
B60J010/04 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 30, 2012 |
KR |
10-2012-0095461 |
Claims
1-12. (canceled)
13. A doorbelt molding for a vehicle, comprising: an outer frame in
which an anodized layer is disposed on a surface of an aluminum
alloy plate; a clear coating layer disposed on the anodized layer;
and an inner molding disposed integrally with the outer frame by
integrally injection-molding a synthetic resin into the outer
frame.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims under 35 U.S.C. .sctn.119(a) the
benefit of Korean Patent Application No. 10-2012-0095461 filed Aug.
30, 2012, the entire contents of which are incorporated herein by
reference.
BACKGROUND
[0002] (a) Technical Field
[0003] The present invention relates to a doorbelt molding for a
vehicle and a method for manufacturing the doorbelt molding. More
particularly, the present invention relates to a doorbelt molding
for a vehicle and a method for manufacturing the doorbelt molding,
which may improve productivity, and decrease the weight of the
molding while exhibiting corrosion resistance.
[0004] (b) Background Art
[0005] Generally, a door glass moved by a mechanical or electric
force is installed in a vehicle door as illustrated in FIG. 1.
Additionally, a doorbelt molding may be attached to a door frame
mounted with the door glass 3.
[0006] As shown in FIG. 1, the door belt molding 4 may be adhered
to the outer surface of the door glass 3 to prevent impurities or
rainwater from infiltrating into the door frame 2a, to guide the
door glass 3, to prevent vibration of the door glass 3, and to
improve the exterior of the door 2.
[0007] The doorbelt molding 4 may include an outer frame exposed to
the exterior of the vehicle 1 along the line of the doorbelt, an
inner molding contacting the door glass while integrally formed
with the outer frame, an end piece sealing the end portion of the
outer frame.
[0008] Typically, the outer frame is manufactured by continuously
extruding or roll forming a metallic plate such as stainless steel
(SUS).
[0009] In addition, the inner molding may be manufactured by
injection molding of a synthetic resin such as polyvinyl chloride
(PVC), and may include an inner frame formed of a metallic material
inserted therein to maintain stiffness and shape. Furthermore, a
synthetic resin integrally formed with the inner frame may be
manufactured by injection molding.
[0010] Since the outer frame of the doorbelt molding is a surface
member that forms the exterior of the door, outer frames formed of
a glossy or semi-glossy metallic material are conventionally used
to improve the exterior of the door and the vehicle.
[0011] For example, the outer frame in a conventional doorbelt
molding may be manufactured with glossy stainless steel (SUS 430)
and semi-glossy stainless steel (SUS 304). Furthermore, the
inherent gloss of the stainless steel (SUS 430) may be used, or the
surface of the SUS 304 plate may be embossed by a micro-shot
process to achieve a semi-glossy effect by surface diffused
reflection (e.g., diffused reflection by the embossed surface of
the material).
[0012] However, since the conventional outer frame is exposed to
the exterior of the vehicle without an additional surface treatment
due to the corrosion resistance of the SUS material, when the outer
frame is exposed to external corrosive environments for a long
time, rust may occur. In additional, since the SUS material is
expensive compared to other aluminum alloy materials, the
manufacturing cost may increase. Furthermore, there are
difficulties in changing its the color of the material, (e.g.,
implementing various types of colors).
[0013] Another conventional manufacturing method includes
manufacturing an outer frame by performing surface treatment on an
aluminum alloy plate other than SUS, manufacturing a separate inner
molding including an inner frame (e.g., typical aluminum alloy
plate) inserted therein (e.g., injection-molding synthetic resin
integrally formed with inner frame), and assembling the two
components by a fitting method. However, in this method, since two
different components (e.g., an outer frame and an inner molding)
are separately manufactured and then assembled, the productivity
thereof may be reduced.
[0014] The above information disclosed in this hereinabove is only
for enhancement of understanding of the background of the invention
and therefore it may contain information that does not form the
prior art that is already known in this country to a person of
ordinary skill in the art.
SUMMARY OF THE INVENTION
[0015] The present invention provides a doorbelt molding for a
vehicle and a method for manufacturing the doorbelt molding, which
may improve manufacturing productivity and decrease the weight
molding while exhibiting corrosion resistance.
[0016] In one aspect, the present invention provides a method for
manufacturing a doorbelt molding for a vehicle, including:
performing an anodizing treatment on the aluminum alloy plate to
form an anodized layer on a surface of an aluminum alloy plate;
performing a clear coating treatment on the aluminum alloy plate on
which the anodized layer is formed to form a clear coating layer on
the anodized layer; performing roll-forming of the aluminum alloy
plate over which the anodized layer and the clear coating layer are
formed to mold a sectional shape of an outer frame; performing an
injection-molding of a synthetic resin into the outer frame,
wherein the synthetic resin is a material of the inner molding to
form a molding intermediate member in which the outer frame and an
inner molding are integrally formed; and completing the doorbelt
molding by performing a subsequent process including bending and
cutting processes on the molding intermediate member.
[0017] In an exemplary embodiment, the aluminum alloy plate may be
manufactured with a plate formed of 1000 series, 3000 series, or
5000 series aluminum alloy materials
[0018] In another exemplary embodiment, the forming of the anodized
layer may include forming an anodized layer with a thickness of
about 3 micrometers (.mu.m) to about 10 .mu.m on the surface of the
aluminum alloy plate.
[0019] In still another exemplary embodiment, in the forming of the
anodized layer, the anodizing coating treatment may be continuously
performed, by the processor, by winding the aluminum alloy plate
around a winding roll and unwinding the aluminum alloy plate from
an unwinding roll to immerse the aluminum alloy plate between the
unwinding roll and the winding roll in an anodizing bath, and a
traveling speed of the aluminum alloy plate in the anodizing bath
may range from about 6 meters per minute (m/min) to about 8
m/min.
[0020] In yet another exemplary embodiment, the anodizing bath may
include an anodizing coating solution containing about 10 grams per
liter (g/l) to 15 g/l, sodium silicate (Na.sub.2SiO.sub.3)9 water
(H.sub.2O), about 3 g/l to 5 g/l potassium fluoride (KF)2H.sub.2O,
and about 2 g/l, to 4 g/l, potassium hydroxide (KOH), and the
anodizing coating treatment may be performed by passing the
aluminum alloy plate through the coating solution that is
maintained at a temperature of about 30.degree. C. to 50.degree. C.
and applying a voltage of about 50 V to 70 V for about 1 to 2
minutes.
[0021] In still yet another exemplary embodiment, the forming of
the clear coating layer may include forming a clear coating layer
with a thickness of about 10 .mu.m to 30 .mu.m on the anodized
layer.
[0022] In a further exemplary embodiment, in forming the clear
coating layer, the clear coating treatment may be continuously
performed by winding the aluminum alloy plate around a winding roll
and unwinding the aluminum alloy plate from an unwinding roll to
immerse the aluminum alloy plate between the unwinding roll and the
winding roll in a bath containing a clear coating solution, and a
traveling speed of the aluminum alloy plate in the clear coating
bath may range from about 5 m/min to 7 m/min.
[0023] In another further exemplary embodiment, in forming of the
clear coating layer, the clear coating solution in the clear
coating bath may be maintained at a temperature of about 50.degree.
C. to 70.degree. C.
[0024] In still another further exemplary embodiment, the aluminum
alloy plate may be continuously surface-treated such that the
forming of the anodized layer and the forming of the clear coating
layer are performed while both ends of the aluminum alloy plate are
being wound around the winding roll and unwound from the unwinding
roll, and the forming of the anodized layer, the forming of the
clear coating layer, the molding of the sectional shape of the
outer frame, and the forming of the molding intermediate member may
be sequentially performed.
[0025] In another aspect, the present invention provides a doorbelt
molding for a vehicle, including an outer frame in which an
anodized layer is disposed on a surface of an aluminum alloy plate
and a clear coating layer is disposed on the anodized layer, and an
inner molding may be disposed integrally with the outer frame by
integrally an injection-molding of a synthetic resin into the outer
frame.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The above and other features, objects and advantages of the
present invention will now be described in detail with reference to
exemplary embodiments thereof illustrated in the accompanying
drawings which are given hereinbelow by way of illustration only,
and thus are not limitative of the present invention, and
wherein:
[0027] FIG. 1 is an exemplary side view illustrating a vehicle
equipped with a doorbelt molding, according to the related art;
[0028] FIG. 2 is an exemplary view illustrating a method of
manufacturing a doorbelt molding according to an exemplary
embodiment of the present invention;
[0029] FIG. 3 is an exemplary cross-sectional view illustrating a
surface-treated aluminum alloy plate constituting an outer frame
according to an exemplary embodiment of the present invention;
and
[0030] FIG. 4 is an exemplary image illustrating a change of the
exterior of a conventional product and a product according to an
exemplary embodiment of the present invention.
[0031] Reference numerals set forth in the Drawings includes
reference to the following elements as further discussed below:
TABLE-US-00001 1: vehicle 2: door 2a: door frame 3: door glass 4:
doorbelt molding 5: outer frame 6: aluminum alloy plate 7a:
anodized layer 7b: clear coating layer 8: inner molding 9a: end
piece 9b: pad 11: unwinding roll 12: winding roll 13: anodizing
bath 14: clear coating bath
[0032] It should be understood that the accompanying drawings are
not necessarily to scale, presenting a somewhat simplified
representation of various exemplary features illustrative of the
basic principles of the invention. The specific design features of
the present invention as disclosed herein, including, for example,
specific dimensions, orientations, locations, and shapes will be
determined in part by the particular intended application and use
environment.
[0033] In the figures, reference numbers refer to the same or
equivalent parts of the present invention throughout the several
figures of the drawing.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0034] Hereinafter reference will be made in detail to various
embodiments of the present invention, examples of which are
illustrated in the accompanying drawings and described below. While
the invention will be described in conjunction with exemplary
embodiments, it will be understood that present description is not
intended to limit the invention to those exemplary embodiments. On
the contrary, the invention is intended to cover not only the
exemplary embodiments, but also various alternatives,
modifications, equivalents and other embodiments, which may be
included within the spirit and scope of the invention as defined by
the appended claims.
[0035] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
the invention. As used herein, the singular forms "a", "an" and
"the" are intended to include the plural forms as well, unless the
context clearly indicates otherwise. It will be further understood
that the terms "comprises" and/or "comprising," when used in this
specification, specify the presence of stated features, integers,
steps, operations, elements, and/or components, but do not preclude
the presence or addition of one or more other features, integers,
steps, operations, elements, components, and/or groups thereof. As
used herein, the term "and/or" includes any and all combinations of
one or more of the associated listed items.
[0036] It is understood that the term "vehicle" or "vehicular" or
other similar term as used herein is inclusive of motor vehicles in
general such as passenger automobiles including sports utility
vehicles (SUV), buses, trucks, various commercial vehicles,
watercraft including a variety of boats and ships, aircraft, and
the like, and includes hybrid vehicles, electric vehicles, plug-in
hybrid electric vehicles, hydrogen-powered vehicles and other
alternative fuel vehicles (e.g., fuels derived from resources other
than petroleum). As referred to herein, a hybrid vehicle is a
vehicle that has two or more sources of power, for example both
gasoline-powered and electric-powered vehicles.
[0037] Unless specifically stated or obvious from context, as used
herein, the term "about" is understood as within a range of normal
tolerance in the art, for example within 2 standard deviations of
the mean. "About" can be understood as within 10%, 9%, 8%, 7%, 6%,
5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the stated
value. Unless otherwise clear from the context, all numerical
values provided herein are modified by the term "about."
[0038] The present invention relates a doorbelt molding for a
vehicle and a method for manufacturing the doorbelt molding, which
may improve manufacturing productivity, and reduce the weight of
the molding while exhibiting corrosion resistance.
[0039] In the manufacturing method of the present invention an
outer frame may be manufactured by anodizing (e.g., anodic
oxidation) treatment, clear coating treatment, and roll-forming and
an inner molding may be integrally injection-molded into the
roll-formed outer frame.
[0040] As shown in FIG. 2, the manufacturing method according to an
exemplary embodiment of the present invention may include a process
of anodizing an aluminum alloy plate 6 used as a material for an
outer frame 5, a process of clear-coating the anodized plate 6, a
process of forming a sectional shape of the outer frame 5 by
roll-forming the anodized and clear coated plate 6, integrally
injection-molding a synthetic resin into the roll-formed outer
frame 5 to manufacture a molding intermediate member 4a in which
the outer frame 5 and the inner molding 8 are integrally formed,
wherein the synthetic resin is a material of an inner molding 8.
The above processes may be sequentially performed, and then
subsequent processes including bending and cutting processes may be
performed on the molding intermediate member 4a to manufacture a
door belt molding 4.
[0041] In this embodiment, a conventional aluminum alloy plate that
is relatively inexpensive may be used as a material of the outer
frame 5 instead of an expensive stainless steel (SUS)
conventionally used as a material of the outer frame in a
semi-glossy molding.
[0042] The outer frame 5 may include a plate formed of one of 1000
series (or expressed as 1XXX series), 3000 series (3XXX series),
and 5000 series (5XXX series) aluminum alloy material. Examples of
an available alloy material are shown in Table 1 below.
TABLE-US-00002 TABLE 1 Content and Composition (wt %) Division Cr
Cu Fe Mg Mn Si Ti Zn Al A 1050 below below below below below below
below below rest 0.05 0.1 0.4 0.05 0.05 0.25 0.03 0.05 A 5052
0.15~0.35 below below 2.2~2.8 below below below below rest 0.1 0.4
0.1 0.25 0.015 0.1 A 5754 below below below 2.6~3.6 below below
below below rest 0.3 0.1 0.4 0.5 0.4 0.15 0.2 A 3005 below below
below 0.2~0.6 1.0~1.5 below below below rest 0.1 0.3 0.7 0.6 0.1
0.25
[0043] In an embodiment of the present invention, an aluminum alloy
plate 6 having a particular width may be used as a plate formed of
the above-mentioned alloy materials. Moreover, the aluminum alloy
plate 6, as shown in FIG. 2, may be continuously surface-treated by
an anodizing process and a clear coating process while allowing
both end portions of the aluminum alloy plate to be wound around
rolls 11 and 12. The section of the surface-treated alloy plate is
shown in FIG. 3 (showing the sectional structure of a final outer
frame 5).
[0044] In the anodizing process, detailed processes such as
cleaning, etching, activation, coating, sealing, and drying are
performed on the aluminum alloy plate 6 to form an anodized layer
7a on the surface of the aluminum alloy plate 6. In the coating
process, as shown in FIG. 2, the plate 6 may be immersed (e.g.,
immersed in an anodizing coating solution) in an anodizing bath 13
to allow the continuous anodizing process to be performed.
Moreover, the plate 6 may be unwound from an unwinding roll 11, and
may be wound around a winding roll 12.
[0045] Furthermore, the plate 6 traveling through the anodizing
bath 13 may move at a particular speed to form a particular
thickness of the anodized layer 7a on the surface of the plate 6.
In an exemplary embodiment, the anodized layer 7a may have a
thickness of about 3 .mu.m to 10 .mu.m by continuously performing
the anodizing treatment on the surface of the aluminum alloy plate
6 having a thickness of about 0.5 mm to 1.0 mm.
[0046] Specifically, when the thickness of the anodized layer 7a is
substantially less than about 3 .mu.m, the thickness of the
anodized layer 7a may be too thin to prevent corrosion.
Accordingly, sufficient corrosion resistance required for a finally
molded product may be obtained, and corrosion may occur when the
plate may be exposed to a corrosive environment while attached to a
vehicle. On the other hand, when the thickness of the anodized
layer 7a is greater than about 10 .mu.m, the layer may be
undesirably ruptured in a subsequent roll-forming process.
[0047] Additionally, in the continuous anodizing process of the
plate using the winding and unwinding rolls 11 and 12, the
conveying speed of the plate 6, (e.g., the traveling speed of the
plate 6) in the bath 13 may be set to about 6 m/min to 8 m/min.
However, when the transfer speed deviates from the above range, the
final thickness of the anodized layer 7a may be too thin or too
thick (e.g., the thickness of the anodized layer 7a may deviate
from the above-mentioned thickness range).
[0048] The surface of the anodized layer 7a formed as above may be
porous. Since the thickness of the layer may be thin, the inherent
metallic color of the aluminum alloy plate 6 thereunder may be
projected to the outside, and simultaneously, the surface gloss may
become semi-glossy by the diffused reflection of the surface
layer.
[0049] Table 2 below shows an exemplary anodizing treatment
condition according to an embodiment of the present invention. The
setting of the coating condition may be important to obtain a
desired thickness of the anodized layer.
TABLE-US-00003 TABLE 2 Composition Division (Aqueous Solution)
Conditions Cleaning 30 g/l Na.sub.3PO.sub.4 Cathodic cleaning for
0.5 to 3 mins Current density 1 to 4 A/dm, 4 to 6 V Etching 180 g/l
CrO.sub.3 Immerse at 20.degree. C. to 30.degree. C. for 3 mins
Activation 2 to 4 g/l KOH Immerse at 20.degree. C. to 30.degree. C.
for 2 mins Coating 10 to 15 g/l Na.sub.2SiO.sub.3.cndot.9H.sub.2O,
Apply voltage of 50 V to 3 to 5 g/l KF.cndot.2H.sub.2O, 70 V at
40.degree. C. for 1 to 2 mins 2 to 4 g/l KOH Sealing ethylene
Immerse at 20.degree. C. to 30.degree. C. for 1 min Drying --
Maintain at 90 .+-. 10.degree. C. for 10 to 20 mins
[0050] As shown in Table 2, after a cleaning process using an
Na.sub.3PO.sub.4 solution, an etching process of immersing the
plate in a chromium trioxide (CrO.sub.3) solution, and an
activation process of immersing the plate in a KOH solution, an
anodizing coating process of conveying the plate 6 through a
coating solution that may be maintained in the anodizing bath 13 at
a temperature of about 30.degree. C. to 50.degree. C. and applying
a voltage of about 50 V to 70 V for about 1 to 2 minutes may be
performed. Thereafter, a sealing process of immersing the plate 6
in ethylene of about 20.degree. C. and a drying process of
maintaining the plate 6 at a temperature of 90.+-.10.degree. C. for
about 10 to 20 minutes may be performed to form the anodized layer
7a on the surface of the plate 6.
[0051] The coating solution used in the anodizing coating process
may include about 10 g/l, to 15 g/l, Na.sub.2SiO.sub.39H.sub.2O,
about 3 g/l, to 5 g/l, KF2H.sub.2O, and about 2 g/l, to 4 g/l,
KOH.
[0052] To form the anodized layer 7a with a thickness of about 3
.mu.m to 10 .mu.m on the surface of the aluminum alloy plate 6, the
conditions of the coating process described above must be satisfied
among the anodizing treatment conditions.
[0053] Among the anodizing process, the cleaning and etching
processes may be performed to remove impurities from the surface of
the aluminum alloy plate 6, and the activation process may be
performed to neutralize the acidified surface of the plate 6 to
facilitate the anodizing coating.
[0054] Additionally, the sealing process may be performed to fill
pores of the surface that may be anodized (e.g., in which the
anodized layer is formed), and the drying process may be performed
to promote infiltration of the sealing solution into pores.
[0055] Thus, the anodized layer 7a may be an anodized film formed
of aluminum oxide (Al.sub.2O.sub.3) with a thickness of about 3
.mu.m to 10 .mu.m may be formed on the surface of the aluminum
alloy plate 6.
[0056] In the coating process of the anodizing process, when a dye
is mixed and added to the coating solution, various colors such as
red, blue, and gold may be reflected on the surface of the aluminum
alloy plate 6, allowing the doorbelt molding to have a desired
color.
[0057] Thus, the present invention has an advantage of
manufacturing various colors of products compared to the related
art in which a SUS material is used.
[0058] Similarly to the anodizing process, the clear coating
process may be performed by conveying the anodized plate 6 through
the bath 14 containing a clear coating solution using the unwinding
roll 11 and the winding roll 12. The plate 6 may be wound around
the winding roll 12 while being unwound from the unwinding roll 11,
and the plate 6 between the unwinding roll 11 and the winding roll
12 may be immersed in a coating solution of the clear coating bath
14 to allow the clearing coating treatment to be continuously
performed.
[0059] Furthermore, the movement speed of the plate 6 traveling
through the clear coating bath 14 may be maintained at a particular
speed such that a clear coating layer 7b with a desired thickness
may be formed on the surface of the plate 6.
[0060] In an exemplary embodiment, the clear coating layer 7b with
a thickness of about 10 .mu.m to 30 .mu.m may be formed on the
anodized layer 7a of the aluminum alloy plate 6. When the clear
coating layer 7b is formed to have a thickness of less than about
10 .mu.m, sufficient corrosion resistance required for a molded
product may not be obtained, and corrosion may occur when exposed
to a corrosive environment while attached to a vehicle.
[0061] On the other hand, when the thickness of the clear coating
layer 7b is greater than about 30 .mu.m, the layer may be
undesirably ruptured in a subsequent roll-forming process.
[0062] Table 3 below shows an exemplary clear coating condition
according to an exemplary embodiment of the present invention,
which illustrates the composition and the content range of a
desired clear coating solution.
TABLE-US-00004 TABLE 3 Chemicals CAS No. Content (wt %)
Cyclohexanone 108-94-1 15 to 20 Blocked Isocyanate -- 20 to 30
Polyester -- 30 to 40 Aromatic Solvent 64742-95-6 15 to 20
Micronized Silica 7631-86-9 4 to 8 Other Additives -- 1 to 5
[0063] In addition, in the continuous clear coating process of the
plate 6 using the rolls 11 and 12, the conveying speed of the plate
6, (e.g., the conveying speed of the plate 6) in the bath 14 may be
set to about 5 m/min to 7 m/min to obtain the coating thickness of
the above-mentioned range. Moreover, the temperature of the coating
solution may be maintained at about 50.degree. C. to 70.degree. C.
to obtain a substantially uniform clear coating layer 7b.
[0064] When the conveying speed is slower than about 5 m/min, the
coating thickness may deviate from the above-mentioned range and
thus may become too thick. On the other hand, when the conveying
speed is faster than about 7 m/min, the coating thickness may
deviate from the above-mentioned range and thus may become too
thin.
[0065] When the coating temperature is less than about 50.degree.
C., an orange peel may occur on the surface of the clear coating
layer 7b due to an incomplete filling of the mold or a rough and
porous finish. On the other hand, when the coating temperature is
maintained at a temperature greater than about 70.degree. C., the
coating solution may not remain on the surface of the plate 6,
making coating difficult.
[0066] The clear coating layer 7b formed by the above process
condition may serve to improve the corrosion resistance of the
plate 6 by blocking humidity and salt water. When only the anodized
layer 7a is formed without the clear coating layer 7b, the surface
of the anodized plate 6, i.e., the surface of the anodized layer
may be directly exposed to the outside, causing significant
reduction of the corrosion resistance. Accordingly, in this
embodiment, the clear coating process may be performed after the
anodizing treatment. Thus, the aluminum alloy plate may exhibit
improved corrosion resistance.
[0067] After the anodized layer 7a and the clear coating layer 7b
are formed on the surface of the aluminum alloy plate 6 through the
surface treatment process, the surface-treated aluminum alloy plate
6 may be mounted into a roll-forming machine 15 to continuously
form the sectional shape of the outer frame 5.
[0068] Thereafter, after the outer frame 5 is completed, the inner
molding 8 that may reduce friction upon raising and lowering of the
door glass may be injection-molded into the outer frame 5 in a
subsequent process to form a molding intermediate member 4a in
which the outer frame 5 and the inner molding 8 are integrally
formed. Moreover, the inner molding 8 may be formed of a PVC
material, which is integrally injection-molded into the outer frame
5 to complete the molding intermediate member 4a in which the outer
frame 5 formed of an aluminum alloy plate and the inner molding 8
formed of PVC are integrally formed.
[0069] Thereafter, as a subsequent process, bending of the molding
intermediate member 4a, assembling of the end piece 9a, and
attachment of the pad 9b may be performed to complete the doorbelt
molding 4. Thus, a final doorbelt molding using a relatively
inexpensive aluminum alloy plate (1000 series, 3000 series, or 5000
series aluminum alloy plate) may be provided.
[0070] Thus, in this embodiment, a doorbelt molding with exhibiting
improved corrosion resistance may be manufactured using a
relatively inexpensive aluminum alloy. Finally, in the
manufacturing of the doorbelt molding, the manufacturing cost can
be reduced, and the weight of the molding decreases, implementation
of various colors (semi-glossy, matt, aluminum metal color, or
other various color), and manufacture of products exhibiting
improved corrosion resistance may be achieved.
[0071] Additionally, in the manufacturing method of the present
invention, since anodizing and clear coating treatment may be
consecutively performed and continuous PVC injection may be
performed to manufacture the product, the manufacturing
productivity may be improved and the manufacturing cost may be
reduced compared to a conventional manufacturing method in which an
outer frame and an inner molding are separately manufactured and
assembled by a fitting method.
[0072] Table 4 below shows a result of evaluating the roll-forming,
PVC extrusion, bending, and assembling characteristics of the outer
frame in which the anodizing treatment and the clear coating
treatment are performed in the manufacturing process of the present
invention. As described above, these characteristics satisfy
particular evaluation criteria when the outer frame that the
anodizing treatment and the clear coating treatment are
performed.
TABLE-US-00005 TABLE 4 Evaluation Item Result Roll-Forming
Satisfied PVC extrusion Satisfied Bending Satisfied Assembling
Satisfied
[0073] In addition, Table 5 below shows properties of 1000 series,
3000 series, and 5000 series aluminum alloy plates that may be used
as a material of the outer frame. More specifically, the evaluation
results of the properties of A 1050, A 3005, A 5052, and A 5754 are
shown in Table 5.
TABLE-US-00006 TABLE 5 Division Present Invention Material of outer
A 1050 A 3005 A 5052 A 5754 frame Yield strength (Y.S) 140 170 197
220 (Mpa) Tensile strength 160 190 241 250 (U.T.S) (Mpa) Elongation
(E.L) (%) 10 7 7.5 10 Thickness (t) of outer 0.5 0.7 0.8 0.5 0.5
0.5 frame (mm) Y.S X t.sup.2 35 68.6 89.6 80.3 82.6 85.3 (dent
resistance .varies. Y.S X t.sup.2) Dent resistance 0.7 0.3 0.2 0.4
0.3 0.2 displacement (mm)
[0074] Also, Table 6 below shows results of a single item and
on-vehicle test regarding a doorbelt molding manufactured according
to an embodiment of the present invention, which shows results of a
water resistance test, a thermal cyclic resistance test, a salt
spray test (SST), and a composite cyclic corrosion test (CCT).
Table 6, illustrates change occurring on the exterior of a product
manufactured according to an embodiment of the present
invention.
TABLE-US-00007 TABLE 6 Item Result Environmental Water resistance
No change on exterior resistance Thermal cyclic No change on
exterior resistance Corrosion resistance SST No change on exterior
CCT No change on exterior Weather resistance No change on
exterior
[0075] Additionally, FIG. 4 illustrates exterior changes on a
conventional product (e.g., SUS 430 used as a material of the outer
frame) and a product manufactured according to an embodiment of the
present invention. Corrosion (indicated by an ellipse) may in a
conventional product (e.g., SUS 430), whereas no change occurs on
the exterior of a product (e.g., made from Al) manufactured
according to an exemplary embodiment of the present invention.
[0076] According to an embodiment of the present invention, a
doorbelt molding having improved corrosion resistance may be
manufactured using a relatively inexpensive and light aluminum
alloy. Additionally, in the manufacture of the doorbelt molding, it
may be possible to manufacture the products in a variety of colors.
Furthermore, since anodizing and a clear coating treatment are
consecutively performed and continuous PVC injection is performed
to manufacture an integral product, the manufacturing productivity
may be improved and the manufacturing cost may be decreased in
comparison to a conventional manufacturing method in which an outer
frame and an inner molding are separately manufactured and
assembled by a fitting method.
[0077] The invention has been described in detail with reference to
exemplary embodiments thereof. However, it will be appreciated by
those skilled in the art that changes may be made in these
embodiments without departing from the principles and spirit of the
invention, the scope of which is defined in the appended claims and
their equivalents.
* * * * *