U.S. patent application number 11/512329 was filed with the patent office on 2007-03-01 for method for manufacturing wheels.
This patent application is currently assigned to WORK CO., LTD.. Invention is credited to Takeshi Tanaka.
Application Number | 20070044311 11/512329 |
Document ID | / |
Family ID | 37802048 |
Filed Date | 2007-03-01 |
United States Patent
Application |
20070044311 |
Kind Code |
A1 |
Tanaka; Takeshi |
March 1, 2007 |
Method for manufacturing wheels
Abstract
To provide a manufacturing method of wheels which can easily and
beautifully remove plating at the welding planned portion and which
can manufacture wheels with rims plated at low price and
efficiently. A method for manufacturing two-piece type wheels
having a rim 2 and a disk, in which after providing a chromium
plating to the rim 2 as a wheel component member, a welding planned
portion RW with respect to the disk on the inner circumferential
surface of the rim is ground by a grinding belt 29, removing
plating at the welding planned portion RW, thereafter the disk is
fitted and fixed to the rim 2 so that the disk and the rim are
welded and joined along the welding planned portion RW.
Inventors: |
Tanaka; Takeshi; (Osaka,
JP) |
Correspondence
Address: |
ARMSTRONG, KRATZ, QUINTOS, HANSON & BROOKS, LLP
1725 K STREET, NW
SUITE 1000
WASHINGTON
DC
20006
US
|
Assignee: |
WORK CO., LTD.
Higashiosaka-shi
JP
|
Family ID: |
37802048 |
Appl. No.: |
11/512329 |
Filed: |
August 30, 2006 |
Current U.S.
Class: |
29/894.321 ;
29/894.3 |
Current CPC
Class: |
Y10T 29/49492 20150115;
Y10T 29/49497 20150115; Y10T 29/49499 20150115; B21D 53/26
20130101 |
Class at
Publication: |
029/894.321 ;
029/894.3 |
International
Class: |
B21D 53/26 20060101
B21D053/26 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 1, 2005 |
JP |
2005-253019 |
Jun 5, 2006 |
JP |
2006-155696 |
Claims
1: A method for manufacturing wheels, comprising steps of:
providing a chromium plating treatment for wheel component members;
grinding a welding planned portions of each of the wheel component
members by an abrasive cloth/paper to remove plating of the welding
planned portion; and welding to join each of the wheel component
members along the relevant welding planned portions.
2: A method for manufacturing two-piece type wheels having a rim
and a disk, comprising steps of: providing a chromium plating
treatment for the rim as a wheel component member; grinding a
welding planned portion to the disk on an inner circumferential
surface of the rim by an abrasive cloth/paper to remove plating of
the welding planned portion; fitting and fixing the disk to an
inside of the rim; and welding to join the disk and the rim along
the relevant welding planned portions.
3: The method for manufacturing wheels according to claim 2 wherein
the welding planned portion is ground by pressing and bringing the
abrasive cloth/paper into contact with the inner circumferential
surface on a bottom of the rim with the rim set in a state of
setting a center axis thereof made substantially parallel to
support rollers onto two of the parallel support rollers with
center axes thereof made substantially horizontal when the inner
circumferential surface of the rim is being ground.
4: The method for manufacturing wheels according to claim 2,
wherein one end of a grinding belt used as the abrasive cloth/paper
is stretched over a pulley which can be inserted in the wheel and
is rotatable around a center axis thereof substantially parallel to
a center axis of the wheel, and the other end is stretched over a
pulley rotatable around a vertical center axis thereof arranged
outside of the wheel.
5: A method for manufacturing three-piece type wheels having an
inner rim, an outer rim, and a disk, comprising steps of: providing
a chromium plating treatment to the outer rim as a wheel component
member; grinding a welding planned portion on an outer
circumferential surface of a curved portion linked from a
superimposed parts of rims to a cylindrical body part in the outer
rim by an abrasive cloth/paper to remove plating of the welding
planned portion; assembling both of the rims by superimposing the
superimposed parts while superimposing an outer circumferential
parts of the disk to the superimposed parts; fixing the disk to the
superimposed parts with bolts; and welding to join the welding
planned portions of both of the rims from an outside.
6: The method for manufacturing wheels according to claim 5,
wherein a flap wheel with an abrasive cloth arranged radially is
used as the abrasive cloth/paper, and the flap wheel is pressed and
brought into contact with a center part of the welding planned
portion in a substantially vertical state so as to grind the
welding planed portion.
7: The method for manufacturing wheels according to claim 3,
wherein one end of a grinding belt used as the abrasive cloth/paper
is stretched over a pulley which can be inserted in the wheel and
is rotatable around a center axis thereof substantially parallel to
a center axis of the wheel, and the other end is stretched over a
pulley rotatable around a vertical center axis thereof arranged
outside of the wheel.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Technical Field
[0002] The present invention relates to a method for manufacturing
wheels.
[0003] 2. Background Art
[0004] As wheels for vehicles made of aluminum alloys and other
light alloys, widely practiced wheels include one-piece wheels
integrally formed by welding, two-piece wheels configured by
dividing the wheel into two parts that are a rim and a disk, and
three-piece wheels configured by dividing the wheel into three
parts that are an inner rim, an outer rim, and a disk.
[0005] As a manufacturing method of two-piece wheels, there is a
widely adopted manufacturing method in which a cylindrical rim is
heated to fit a disk in the inside of which a disk is fitted, and
in a state that the disk is fitted and fixed to a suitable place in
the axial direction of the rim by shrinkage-fitting, an outer
circumferential surface of the disk is welded to an inner
circumferential surface of the rim in order to integrate the disk
and the rim into one.
[0006] As a manufacturing method of three-piece wheels, there is a
widely adopted manufacturing method in which an annular
superimposed part extending inwards in the radial direction is
formed on one end part of each of the inner rim and the outer rim
respectively, superimposing the superimposed parts to assemble both
of the rims concentrically, superimposing the superimposed part to
an outer circumferential part of the disk under the above state,
tightening these three parts by bolts, after which welding is
provided from the outer circumferential side along the superimposed
portion of the inner rim and the outer rim, so that both of the
rims are airtightly integrated into one.
[0007] On the other hand, a wheel subjected to a plating treatment
such as chromium plating to enhance design features is proposed and
put into practical use. In one-piece wheels, a whole wheel is
immersed into plating liquid to carry out a plating treatment (for
example, refer to Japanese Unexamined Patent Publication No. Hei
11-236681). However, in two-piece wheels and three-piece wheels,
presence of plating at a welding planned portion of each of the
wheel component members generates welding defects, and the
following plating treatment is therefore implemented.
[0008] That is, in two-piece wheels, a welding planned portion is
formed in at a halfway of an inner circumferential surface of a rim
in the axial direction, causing it extremely troublesome to remove
plating of the welding planned portion. Therefore, a wheel is
generally configured to to provide a plating treatment only for a
disk, not for a rim. Consequently, it is possible to fabricate a
two-piece wheel in which a plating treatment is provided for a rim,
but a plating treatment is not provided for a rim of a widely used
wheel due to an increased manufacturing cost.
[0009] In addition, in three-piece wheels, in order to increase
design features, a plating treatment is provided for a disk and an
outer rim, while for the inner rim having little effects on design
features, an alumite treatment is provided in place of the plating
treatment to reduce a manufacturing cost. Also, in order to prevent
welding defects of rims caused by plating or oxide coating, with
respect to the outer rim, the outer rim is immersed in plating
liquid to carry out plating treatment in a state of, for example,
providing masking for a welding planned portion, or plating of the
welding planned portion of the outer rim which have been subjected
to a plating treatment is removed manually by the use of a portable
grinder or the like, or plating of the welding planned portion of
the outer rim is removed by cutting in a machine process, and with
respect to the inner rim, oxide film of the welding planned portion
is removed manually by the use of, for example, a wire brush or the
like.
SUMMARY OF THE INVENTION
[0010] In two-piece wheels, there is no two-piece wheel having a
plated rim that are widely used and in three-piece wheels, there
are following problems when plating of a welding planned portion of
an outer rim is removed.
[0011] That is, in the event that a welding planned portion of an
outer rim is provided with masking to carry out a plating
treatment, there are problems that a troublesome operation of
affixing masking tape is required. In addition, since plating
treatment requires special technique and it is not generally
carried out by a wheel manufacturer but by a manufacturer
specialized in a plating treatment, there is a problem of
increasing a labor cost for a plating treatment for an operation of
affixing a masking tape and increasing the a wheel manufacturing
cost.
[0012] Since delicate irregularities are formed on an outer surface
of the outer rim, even if the masking tape is neatly affixed, the
plating liquid may invade between the masking tape and the rim when
the rim is immersed in plating liquid and part of the welding
planned portion may be plated, which is made to be one of the
causes in welding defects of the plating part in the welding
planned portion. Furthermore, in the event that chromium plating is
provided as a plating treatment, a rim is successively immersed in
a plurality of treatment liquid, the plating liquid that invaded
between a masking tape and the rim is brought into the other
treatment liquid in the subsequent processes, creating a problem of
contaminating treatment solutions in the subsequent processes.
Still more, an adhesive component of a masking tape is dissolved
into treatment liquid, resulting in a problem of degrading
treatment liquid.
[0013] Furthermore, in the case of masking, as shown in FIG. 15,
there is a problem that, at the boundary part 103 between a base
material area 101 formed on a welding planned portion of a rim 100
by affixing a masking tape and a plated area 102 other than the
base material area 101, an elevated part 104 is formed along a side
edge of a masking tape on the plated area 102, and a level
difference is formed at the boundary 103 between the base material
area 101 and the plated area 102, causing easy exfoliation of
plating by a physical shock, and a formation of an incomplete
plated area 105 such as, for example, a copper plating layer as a
substrate layer in the case of chromium plating, by plating liquid
invaded between the masking tape and the rim, and resulting in easy
exfoliation of the plated area 102 from the relevant portion
105.
[0014] On the other hand, in the event that plating of a welding
planned portion is removed by cutting or the like in a machine
process, plating of the welding planned portion can be neatly
removed and an operation of affixing masking tape is not required,
besides affixing a masking tape is not necessary, thereby a labor
cost of plating treatment is minimized, the manufacturing cost of a
wheel can be reduced. However, cutting a plated area by a single
cutting treatment causes a force exerted to the plated area in the
direction to exfoliate plating when a cutting tool is withdrawn
from the plated area, resulting in a problem of easy exfoliation of
the plated area from the boundary with a base material portion. In
addition, in order to prevent the above stated problem, it is
assumed to insert a cutting tool from both side edges of welding
planned portion and to allow the cutting tool to withdraw at
halfway in the width direction of the welding planned portion.
However, it is required to implement a cutting treatment twice,
resulting in a problem of extremely troublesome operation.
Furthermore, in the event removing plating of an outer
circumferential face of a curved part linked from a superimposed
portion of rims to a cylindrical body part as is the case of a
three-piece wheel, a cutting tool must be moved along the curved
surface of the curved part which is different in a curvature among
different types of wheels, resulting in a problem that control of
the cutting tool is made extremely complicated.
[0015] In addition, in a method to remove plating of the welding
planned portion by a manual operation using a portable grinder or
the like, processing carried out from an outer circumference side
of an outer rim enables removal of plating with a comparative
easiness even at a curved welding planned portion, but there are
problems of requiring workforce and generating variations in
dimensional accuracies and surface properties of a grinding
surface.
[0016] It is an object of the present invention to provide a
manufacturing method of wheels which can easily and neatly remove
plating of a welding planned portion and manufacture wheels with
rims efficiently plated at low cost.
[0017] A first manufacturing method of wheels related to the
present invention includes steps of providing a chromium plating
treatment to wheel component members, grinding a welding planned
portion of the wheel component members by an abrasive cloth/paper,
removing plating of the welding planned portion, and welding and
joining the wheel component members along the welding planned
portion.
[0018] A second manufacturing method of wheels related to the
present invention is a manufacturing method of two-piece type
wheels composed of a rim and ad disk, in which after providing a
chromium plating treatment to a rim as a wheel component member, a
welding planned portion with a disk on an inner circumferential
surface of the rim is ground by an abrasive cloth/paper, removing
plating of the welding planned portion, after which the disk is
fixed into the rim, so that the disk and the rim are welded and
joined along the welding planned portion.
[0019] In this second manufacturing method of wheels, a preferable
embodiment includes steps such as using a grinding belt in which
one end of the abrasive cloth/paper is stretched over a pulley
capable of being inserted in the wheel and rotatable around a
center axis thereof substantially parallel to a center axis of the
wheel and the other end of the abrasive cloth/paper is stretched
over a pulley rotatable around a vertical center axis thereof
arranged outside of the wheel, and grinding with the abrasive
cloth/paper pressed and brought in contact with the inner
circumferential surface on a bottom of the rim under a condition
that the rim is set with a center axis thereof made substantially
in parallel to the support roller onto two parallel support rollers
with center axes thereof made substantially horizontal at the
grinding of inner circumferential of the rim.
[0020] A third manufacturing method of wheels related to the
present invention is a manufacturing method of three-piece type
wheels composed of an inner rim, an outer rim, and a disk, in which
a chromium plating treatment is first provided for the outer rim as
a wheel component member, then grinding a welding planned portion
on an outer circumferential surface of the curved part linked from
a superimposed part of rims to cylindrical body part in the outer
rim using an abrasive cloth/paper, removing plating of the welding
planned portion, superimposing a superimposed part to assemble both
of the rims, superimposing an outer circumferential part of the
disk to the superimposed part, after which the disk is fixed to the
superimposed part by bolts, so that the welding planned portions of
both of the rims are welded and joined from an outside. However, in
the event that an alumite treatment is provided for the inner rim,
in a state that oxide film of the welding planned portion of the
inner rim is removed by a wire brush or the like, the superimposed
parts are superimposed to assemble both of the rims.
[0021] In the third wheel manufacturing method, a configuration of
a preferable embodiment is to use a flap wheel with an abrasive
cloth arranged radially as the abrasive cloth/paper to grind the
welding planned portion by pressing and bringing the flap wheel
substantially vertically in contact with a center part of the
welding planned portion.
[0022] According to the first manufacturing method of wheels
related to the present invention, because a welding planned portion
is ground by an abrasive cloth/paper, it is made possible to neatly
and accurately remove chromium plating or the like that is hard. In
addition, as compared to the cases of masking or cutting, it is
possible to prevent a level difference at a boundary between a
welding planned portion from which plating was removed and the
plated area from being angular, and exfoliation of plating from the
boundary can be effectively prevented. Also, as compared to the
case of masking, an operation of affixing a masking tape is not
required, thereby labor cost for a plating treatment can be
minimized and a wheel manufacturing cost can be reduced.
Furthermore, since plating of a welding planned portion can be
neatly removed by grinding, welding defects can be effectively
prevented and stability in a wheel quality can be improved.
[0023] According to the second wheel manufacturing method related
to the present invention, in addition to the effects of the first
wheel manufacturing method, plating of a welding planned portion on
an inner circumferential surfaces of the rims of a two-piece wheel
can be removed, thereby an two-piece wheel which has plated rims
can be fabricated easily and at low cost. In addition, it is made
possible to form a smooth surface between a welding planned portion
from which plating was removed and a plated area free of level
difference, thereby exfoliation of plating at a boundary can be
effectively prevented. In addition, since it is possible to change
a position of a welding planned portion with respect to the axial
direction of a rim by adjusting a position of an abrasive
cloth/paper with respect to the axial direction of the inner
circumferential surface of the rim, thereby it is made possible to
fabricate a two-piece wheel with a disk arranged at an offset
position in accordance with a request from a user.
[0024] In this second wheel manufacturing method, the use of a
grinding belt as the abrasive cloth/paper enables to improve
durability thereof, and a grinding operation can be efficiently
carried out. In addition, a side edge part of the grinding belt
pressed and brought in contact with an inner circumferential
surface of a rim is bent during grinding, thereby a welding planned
portion from which plating was removed and a plated area can be
formed into a smooth surface without having a level difference and
exfoliation of plating at the boundary can be effectively
prevented.
[0025] In addition, setting a rim onto two parallel support rollers
with center axes thereof made substantially horizontal and grinding
an inner circumferential surface on a bottom part of a rim by an
abrasive cloth/paper enable to grind an inner circumferential
surface of the rim at substantially the same height even if plating
of a different seized rim is removed, and there is no need to
adjust a height position of a abrasive cloth/paper for every change
of the rim size, it is therefore possible to adopt a grinding
device with a simple configuration.
[0026] According to the third wheel manufacturing method related to
the present invention, in addition to the effects of the first
wheel manufacturing method, plating of a welding planned portion of
an outer rim can be removed, thereby it is made possible to
fabricate three-piece wheels with a plated outer rim easily and at
low cost. Furthermore, since a welding planned portion at a
superimposed part has a cross-sectional profile protruding
outwards, it is made possible to form a smooth surface between a
welding planned portion from which plating was removed and a plated
area without having a level difference, and as compared to cases of
masking or cutting, exfoliation of plating at a boundary area can
be effectively prevented.
[0027] In the third wheel manufacturing method, when a flap wheel
with an abrasive cloth radially arranged is used as the abrasive
cloth/paper and a welding planned portion is ground by pressing and
bringing the flap wheel in contact with a center part of the
welding planned portion in a substantially vertical state, the
welding planned portion can be ground while an outer
circumferential part of the flap wheel is being bent along a
curvature of the welding planned portion; a required width of the
welding planned portion can be neatly ground by a single grinding
treatment and it is made possible to form a smooth surface between
a welding planned portion and a plated part without a level
difference while preventing the welding planned portion from being
excessively ground, so that exfoliation of plating at the boundary
can be effectively prevented further more. In addition, even in the
case of a wheel with a different curvature at a welding planned
portion, a grinding treatment can be carried out with the same flap
wheel and the operability of grinding treatment can be
improved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 is a front view of a two-piece wheel;
[0029] FIG. 2 is a cross-sectional view taken along a line II-II of
FIG. 1;
[0030] FIG. 3 is a view explaining a wheel manufacturing
process;
[0031] FIG. 4(a) and FIG. 4(b) are views explaining a press process
and FIG. 4(c) and FIG. 4(d) are views explaining machining
process;
[0032] FIG. 5 is a view explaining a spinning process;
[0033] FIG. 6 is a view explaining a plating removing
apparatus;
[0034] FIG. 7 shows an operating state of a plating removing
apparatus; FIG. 7(a) is a view explaining a state of a rim placed
on support rollers; FIG. 7(b) is a view explaining a state of the
rim held by holding rollers; and FIG. 7(c) is a view explaining a
state immediately before a grinding belt is inserted to the
rim;
[0035] FIG. 8 is a view explaining an operating condition of a
plating removing means; FIG. 8(a) is a view explaining a state of a
grinding belt inserted to a rim; FIG. 8(b) is a view explaining a
state when a welding planned place is ground by the grinding belt;
and FIG. 8(c) is a view explaining that a valve fixing hole is
formed by a drill;
[0036] FIG. 9 is a view explaining a ground portion by the grinding
belt;
[0037] FIG. 10 is a cross-sectional view of a three-piece
wheel;
[0038] FIG. 11 is a view showing an operating condition of a
plating removing apparatus; FIG. 11(a) is a view explaining a rim
set to a supporting means and FIG. 11(b) is a view explaining a
state of the rim held by holding rollers;
[0039] FIG. 12 is a view explaining an operating state of a plating
removing apparatus; FIG. 12(a) is a view explaining a state
immediately before a welding planned portion of the rim is ground
by a grinding means and FIG. 12(b) is a view explaining a state of
the welding planned portion of the rim ground with the grinding
means:
[0040] FIG. 13 is a view explaining a grinding operation by
abrasive cloth/paper;
[0041] FIG. 14 is a view explaining a portion to be ground; and
[0042] FIG. 15 is a view explaining a portion to be ground by
masking related to a conventional technique.
DETAILED DESCRIPTION OF THE INVENTION
[0043] Referring to the drawings, embodiments of the present
invention will be described in detail hereinafter.
[0044] First of all, description will be made when the present
invention is applied to a manufacturing method of a two-piece wheel
1.
[0045] As shown in FIG. 1 and FIG. 2, the two-piece wheel 1 is
equipped with a substantially cylindrical rim 2 and a disk 3 fitted
into and fixed to a inside the rim 2, in which the two-piece wheel
1 is assembled by welding an outer circumferential part of the disk
3 to be joined to an inner circumferential surface of the rim 2 in
a state that the disk 3 is fitted and fixed to the rim 2 by
shrink-fitting.
[0046] The disk 3 is integrally formed using aluminum alloys and
other lightweight metal material by casting, press-forming, and
forging or the like, and equipped with a fixing part 4 to a wheel
support member (illustration omitted), an annular ring part 5
installed in such a manner as to surround and enclose the fixing
part 4 and a spoke part 6 that joins the fixing part 4 to the ring
part 5, in which a whole surface thereof is subjected to a
chromium-plating treatment. The plating treatment is carried out by
a widely known method to immerse the rim 2 in plating liquid, and
plating of a welding planned portion DW of the disk 3 with respect
to the rim 2 is removed by masking or grinding.
[0047] The rim 2 is composed with metal material with superb
stretchability such as aluminum alloys, and a whole surface thereof
is subjected to a treatment such as chromium plating. The plating
treatment is carried out by a widely known method to immerse the
rim 2 in plating liquid and plating of a welding planned portion RW
of the rim 2 with respect to the disk 3 is removed in grinding by a
plating removing apparatus 20 discussed below.
[0048] At an end part on a design surface side and an end part on a
fixing surface side of the rim 2, flange parts 7 are formed with a
wall thicker than other parts by increasing a wall thickness.
Because the flange part 7 is configured to be thick by increasing
the wall thickness in this way, when the rim 2 is subjected to a
plating treatment, plating liquid or the like is securely prevented
from remaining inside the flange part 7 and corrosion of the flange
part 7 caused by the remaining plating liquid can be prevented. In
addition, because the flange part 7 is configured to have a thick
wall, strength and rigidity of the wheel 1 can be sufficiently
secured during rotation or the like.
[0049] Next description will be made on a manufacturing method of
the wheel 1.
[0050] The manufacturing method of this wheel 1 is composed of, as
shown in FIG. 3, a rim manufacturing process for manufacturing the
rim 2, a disk manufacturing process for manufacturing the disk 3, a
plating treatment process for providing chromium plating to the rim
2 and the disk 3, a plating removing process for removing plating
of welding planned portions RW and DW between the rim 2 and the
disk 3, and an assembly process for assembling the wheel 1 from the
rim 2 and the disk 3. Because the present invention is
characterized by a configuration of easily and neatly removing
plating of the welding planned portion RW on the inner
circumferential surface of a rim 2, processes other than the
plating removing process of the rim 2 will be briefly
explained.
[0051] In the rim manufacturing process, a disk-form rolled metal
plate 10 with superb stretchability such as aluminum alloy is
press-formed as shown in FIG. 4(a), so as to fabricate a primary
forming 13 having a cylindrical tubular part 11 with a bottom 14
and a flange part 12 that extends outwards from an end part of an
opening side of the tubular part 11 as shown in FIG. 4(b), after
which a primary forming 13A is fabricated by removing the bottom
part 14 of the primary forming 13 by punching processing or the
like as shown in FIG. 4(c), and a flange part 15 is formed next by
press-forming an opening end part of the primary forming 13A from
which the bottom 14 was removed, so as to fabricate a secondary
forming 16 with flange parts 12 and 15 formed on both ends of the
tubular part 11 as shown in FIG. 4(d). The manufacturing method of
the secondary forming 16 can be provided in such a manner that a
slender rolled metal sheet with outstanding stretchability such as
aluminum alloy is rolled in a cylindrical form and both end parts
are welded to fabricate a tubular member, in which both end parts
of this tubular member is subjected to press-forming to form flange
parts.
[0052] Then, as shown in FIG. 5, the secondary forming 16 is
externally fitted to be fixed to a mandrel 17, and while the
secondary forming 16 is being rotated together with the mandrel 17,
the secondary forming 16 is subjected to spinning processing using
rollers 18 and 19 so that the rim 2 of a cross-sectional form as
shown in FIG. 2 is obtained.
[0053] On the other hand, in the disk manufacturing process, the
disk 3 is fabricated by forming metal material into a disk form by
widely known manufacturing methods such as casting, press-forming,
and forging or the like using aluminum alloys and other lightweight
metal material.
[0054] In the plating treatment process, the disk 3 and the rim 2
are subjected to degreasing, water rinsing, acid treatment, water
rinsing, copper plating, water rinsing, nickel plating, water
rinsing, and chromium plating successively so as to form a chromium
plating layer on a whole surface with two layers of copper and
nickel used as substrate layers on the disk 3 and the rim 2.
[0055] In the plating removal process, the welding planned portions
RW and DW on the rim 2 and the disk 3 are ground to remove the
chromium plating on the welding planned portions.
[0056] When plating of the welding plating portion DW on the disk 3
is ground and removed, the disk 3 is set to a rotary table, and the
welding planned portion on an outer circumferential part of the
disk 3 is subjected to a grinding treatment by a portable grinder
while rotating the disk 3 together with the rotary table, thereby
the chromium plating of the welding planned portion is removed.
However, with respect to the disk 3, it is possible to provide a
configuration to prevent a formation of plating on the welding
planed portion by carrying out a plating treatment with a masking
tape affixed to the welding planned portion at the time of plating,
so as to omit the plating removal process.
[0057] When plating of the welding planned portion RW of the rim 2
is ground and removed, a plating removing apparatus 20 with a
configuration as shown in FIG. 6 is used to remove plating of the
welding planned portion RW by grinding the plating of the welding
planned portion RW using an abrasive cloth/paper composed with a
grinding belt 29.
[0058] The plating removing apparatus 20 is equipped with a pair of
support rollers 21 horizontally arranged by setting center axes
thereof in parallel at an interval smaller than an outer diameter
of the rim, a positioning member 22 for positioning the rim 2
supported on the support rollers 21 with a center axis thereof made
substantially horizontal in the axial direction of the support
roller 21, a pair of holding rollers 23 arranged substantially in
parallel to the support roller 21 above the support roller 21, and
actuator 32 for holding the rim 2 between the support roller 21 and
the holding roller 23 by pressing the rim 2 positioned and held on
the support roller 21 from an upper side by the holding roller 23,
a rotation drive means 24 for rotating and driving the rim 2 held
between the support rollers 21 and holding rollers 23, and a
grinding means 25 that extends to an inside of the rim 2 for
grinding the welding planned portion RW of the rim 2 with respect
to the disk 3 so as to remove plating of the welding planned
portion RW.
[0059] The grinding means 25 is configured to have a drive pulley
26 supported rotatably around a center axis thereof substantially
in parallel to the center axis of support rollers 21, an idler
pulley 27 arranged with a center axis thereof made substantially
vertical, a grinding belt 29 stretched between both the drive
pulley 26 and the idler pulley 27 with a direction thereof changed
at a halfway part by guide rolls 28, a drive means 30 for grinding
that rotates and drives the drive pulley 26, and a pressurizing
cylinder 31 for pressing the grinding belt 29 stretched to the
drive pulley 26 against a welding planned portion on the rim 2, so
as to grind a bottom part of an inner circumferential surface of a
rim by the grinding means 25.
[0060] In this plating removing apparatus 20, a peripheral velocity
of the grinding belt 29 with respect to the welding planned portion
RW is set to 150 to 600 m/min, the pressurizing force with respect
to the rim 2 is set to be 0.5 kN to 1.5 kN, and a rotating speed of
the rim 2 is set to be 5 to 100 rpm so that a grinding treatment
can be implemented for the welding planned portion RW during a
single rotation of the rim 2. However, it is also possible to
provide a configuration to complete the grinding treatment during
multiple rotations of the rim 2. A width of the grinding belt 29 is
set to be equal to or slightly larger than that of the welding
planned portion RW so that plating of the welding planned portion
RW can be ground by a single grinding treatment. However, grinding
can be divided into multiple steps of grinding in the axial
direction.
[0061] When this plating removing apparatus 20 is used to grind a
welding planned portion on an inner circumferential surface of the
rim 2, the rim 2 is placed on the support rollers 21 with a center
axis thereof directed in the horizontal direction first, and then
an end of the rim 2 is brought in contact with the positioning
member 22 to position and set the rim 2 in the horizontal direction
on the support rollers 21 as shown in FIG. 7(a) so that the holding
rollers 23 are protruded downward by the actuator 32 to hold the
rim 2 between the support roller 21 and the holding roller 23 as
shown in FIG. 7(b).
[0062] Then, the grinding means 25 is moved from a retracted
position shown in FIG. 6 and FIG. 7(c) to an advancing position as
shown in FIG. 8(a), in which the support roller 21 is rotated by
the rotation drive means 24 to rotate the rim 2 at low speed with a
rotating speed of, for example, 10 rpm, while allowing the grinding
belt 29 to orbit, and pressing and bringing the grinding belt 29
applied to the drive pulley 26 to be in contact with the welding
planned portion RW on a bottom part of the inner circumferential
surface of the rim 2 rotating at low speed, so that the welding
planned portion RW of the rim 2 rotating at low speed is
successively ground, and plating in the welding planned portion RW
is successively removed as shown in FIG. 8(b).
[0063] After plating of the welding planned portion RW is thus
removed throughout a whole circumference by a single rotation of
the rim 2, the grinding belt 29 is separated from the inner
circumferential surface of the rim 2, and a rotation of the rim 2
by the drive means 30 for grinding is stopped, in which a drill 34
is raised to form a valve fixing hole (refer to FIG. 2) while the
drill 34 is being rotated by the drill drive means 33 as shown in
FIG. 8(c). However, it is possible to provide a configuration to
remove plating of the welding planned portion RW after forming the
valve fixing hole 8 by the drill 34.
[0064] If the plating removing apparatus 20 is used as stated
above, a side edge of the grinding belt 29 is subtly bent as shown
in FIG. 9 while the welding planned portion RW is ground by the
grinding belt 29, a base material surface 2a of the welding planned
portion RW in which plating was removed and a surface of the plated
area 2b is smoothly connected without forming a level difference at
a boundary 2c between the base material surface 2a and the plate
area 2b, thereby effective preventing nonconformity including
exfoliation of the plated area 2b from the boundary 2c during
welding or others.
[0065] In addition, removal of plating of the welding planned
portion RW by grinding enables to neatly remove plating of the
welding planned portion RW in a substantially complete state, and
welding defects of the disk 3 with respect to the rim 2 can be
securely prevented. In addition, since it is possible to plate a
whole surface of the rim 2 without affixing a masking tape, a labor
cost used for a plating treatment can be minimized and a
manufacturing cost of the wheel 1 can be reduced.
[0066] Furthermore, a bottom part of an inner circumferential
surface of the rim 2 is ground in a state that the rim is held by
the support rollers 21, even when a plated area of the rim 2 with a
different size is removed, a grinding portion in the inner
circumferential surfaces of rims 2 is substantially the same
without causing an adjustment of a relationship in height between
the grinding means 25 and the rim 2, thereby a plating removal
operability can be remarkably improved.
[0067] Because grinding can be carried out by the use of the
grinding belt 25, it is made possible to increase a durability of
the grinding belt 29 as a grinding tool while the drive pulley 26
inserted inside the rim 2 is made compact, and a grinding operation
can be efficiently carried out.
[0068] It is also possible to provide a position adjusting means
that adjusts a position to be ground by the grinding means 25 in
the axial direction of the rim 2, and in such event, an axial
position of the welding planned portion RW can be optionally
adjusted, thereby a wheel can be fabricated by adjusting a mounting
position of the disk 3 with respect to the axial direction of the
rim 2 in accordance with a request from a user. In addition, if the
plating of the welding planned portion RW can be removed by
grinding, plating can be removed by a plating removing apparatus
with a configuration other than that of the plating removing
apparatus 20.
[0069] Next in the assembly process, the rim 2 is heated by an
induction heating apparatus, and an inside diameter of the rim 2 is
expanded by thermal expansion, in which the disk 3 is inserted into
a setting position inside the rim 2 in the axial direction and a
temperature of the rim 2 is lowered by air cooling, so that the
disk 3 is fitted and fixed to an inside of the rim 2 by shrink
fitting. Then, TIG welding or MIG welding is carried out to
successively weld and join the welding planned portions DW and RW
of the disk 3 and the rim 2, and to obtain a two-piece wheel 1 as
shown in FIG. 1 and FIG. 2.
[0070] In this manufacturing method of the wheel 1, as described
above, the welding planned portion RW on an inner circumferential
surface of the rim can be easily and neatly ground with accuracy by
grinding, enabling a low manufacturing cost of the two-piece wheel
1 with the rim 2 plated by chromium.
[0071] Next discussion is made on an embodiment in which the
present invention is applied to a fabrication method of a
three-piece type wheel 51.
[0072] As shown in FIG. 10, the three-piece wheel 51 has a
substantially cylindrical outer rim 52A and inner rim 52B which
have an annular superimposed part 52a extending to an inner side on
one end part, and a disk 54 fixed to the superimposed part 52a of
both of the outer rim 52A and the inner rim 52B with a bolt not
shown.
[0073] The disk 54 which is integrally formed using aluminum alloys
and other lightweight metal material by casting, press-forming, and
forging or the like is equipped with a fixing part 55 to a wheel
support member (omitted from drawings), an annular ring part 56
installed in such a manner as to surround and enclose the fixing
part 55 and a spoke part 57 that joins the fixing part 55 to the
ring part 56, in which a whole surface thereof is subjected to a
chromium-plating treatment. The plating treatment is carried out by
a widely known method to immerse the disk 54 in plating liquid.
However, the disk 4 is not necessarily provided with the plating
treatment and may be provided with coating.
[0074] Both the outer rim 52A and the inner rim 52B are composed
with metal material with superb stretchability such as aluminum
alloys and others. A whole surface of the outer rim 52A is
subjected to a plating treatment such as chromium plating and other
plating by a widely known method to immerse the outer rim 52A in
plating liquid in order to improve design features thereof. The
inner rim 52B may be provided with a chromium plating treatment in
the same manner with the outer rim 52A, but an alumite treatment
which can be implemented at low cost is provided for the inner rim
52B which has little effect on the design features.
[0075] In the outer rim 52A and the inner rim 52B, a substantially
cylindrical body part 52b linked to the superimposed part 52a is
formed, and flange parts 52c are formed with a wall thickness
increased to have wall thicker than other parts at the end part on
the design surface side of the outer rim 52A and the end part on
the fixing surface side of the inner rim 52B, respectively. The
flange parts 52c are thus configured to be thick by increasing the
wall thickness, thereby when the outer rim 52A is subjected to a
plating treatment, plating liquid or the like is securely prevented
from remaining inside the flange parts 52c and corrosion of the
flange parts 52c caused by the remaining plating liquid can be
prevented. In addition, because the wall thickness configured on
the flange part 52c of both the outer rim 52A and the inner rim 52B
is sufficiently secure, strength and rigidity of a wheel 51 can be
satisfactorily secured during rotation or the like.
[0076] On an outer circumferential surface of a curved part linked
from the superimposed part 52a to the body part 52b, the welding
planned portions R are respectively formed with plating and oxide
film removed to expose the base material. Plating of the welding
planned portion R on the outer rim 52A is removed by a plating
removing apparatus 60 discussed later to expose the base material
while oxide film of the welding planned portion R of the inner rim
52B is removed by a wire brush or the like to expose the base
material. However, when a plating treatment is provided for the
inner rim 52B, plating of the welding planned portion R is removed
by the plating removing apparatus 60 later discussed in the same
manner as the outer rim 52A.
[0077] When the wheel 51 is assembled, the superimposed parts 52a
of both the outer rim 52A and the inner rim 52B are superimposed,
fixing this superimposed part 52a to an outer circumferential part
of the disk 54 with the bolt 53 and integrating both of the outer
rim 52A and the inner rim 52B to the disk 54 into one, and welding
both of the welding planned portions R from the outer
circumferential side to assemble the wheel 51.
[0078] Next discussion will be made on a manufacturing method of
the wheel 51.
[0079] This manufacturing method of the wheel 51 has a different
content for the operation in each process of the embodiment
described above but has similar processing steps as shown in FIG.
3. Specifically, a configuration of the processing steps includes a
rim manufacturing process for manufacturing the outer rim 52A and
the inner rim 52B, a disk manufacturing process for manufacturing
the disk 54, a plating process for providing a chromium plating
treatment to the outer rim 52A and the disk 54, a plating removing
process for removing plating of the welding planned portion R of
the outer rim 52A with respect to the inner rim 52B, and an
assembly process for assembling the wheel 51 from both of the outer
rim 52A and the inner rim 52B and the disk 54. Because the present
invention is characterized by a configuration to easily and neatly
remove plating of the welding planned portion R of the outer rim
52A, processes other than the plating removing process of the outer
rim 52A will be briefly described.
[0080] Now the rim manufacturing process will be described. In a
press process similar to the above-mentioned embodiment, as shown
in FIG. 4(a), a disk-form rolled metal plate 10 with superb
stretchability such as aluminum alloy is press-formed to fabricate
a primary forming 13 having a cylindrical tubular part 11 with a
bottom 14 and a flange part 12 externally extending from an end
part on an opening side of the tubular part 11. However, when the
outer rim 52A is manufactured, an axial length of the cylindrical
part 11 is set to fit in an axial length of the outer rim 52A, and
when the inner rim 52B is manufactured, it is set to fit in an
axial length of the inner rim 52B. Then, a primary forming 13A is
fabricated by removing a bottom part 14 of the primary forming 13
by punching processing or the like. Whole of the bottom part 14 of
the primary forming 13 may be cut off, but a flange part that
extending to a center part side may be formed by cutting off the
center part only so that the flange part is used for a superimposed
part 52a. Then, the primary forming 13A is externally fitted and
fixed to a mandrel, rotating the primary forming 13A together with
the mandrel, carrying out spinning processing to the primary
forming 13A by using rollers, thereby the outer rim 52A and the
inner rim 52B of a cross-sectional form as shown in FIG. 10 are
obtained.
[0081] In the disk manufacturing process, disk 54 is fabricated by
forming metal material into a disk form by a widely known
manufacturing method such as casting, press-forming, and forging
using aluminum alloys and other lightweight metal material.
[0082] In the plating process, the disk 54 and the outer rim 52A
are subjected to degreasing, water rinsing, acid treatment, water
rinsing, copper plating, water rinsing, nickel plating, water
rinsing, and chromium plating successively so as to form a chromium
plating layer on a whole surface with two layers of copper and
nickel used as a substrate layer on the disk 54 and the outer rim
52A. The chromium plating can also be provided for the inner rim
52B in the same manner with the outer rim 52A, but an alumite
treatment feasible at an inexpensive price is provided for the
inner rim 52B which has little affects on the design features.
[0083] In the plating removal process, plating of the welding
planned portions R on the outer rim 52A is removed by an abrasive
cloth/paper 61 using the plating removing apparatus 60 of the
following configuration and plating at the welding planned portions
is ground and removed.
[0084] As shown in FIG. 11 and FIG. 12, the plating removing
apparatus 60 is equipped with a support means 62 that rotatably
supports the outer rim 52A with a center axis held substantially
vertical, a rotation drive means 64 that rotates and drives the
outer rim 52A supported to the support means 62 held by three
holding rollers 63 from the outer circumferential side, and a
grinding means 65 that removes plating of the relevant welding
planned portion R by grinding the welding planned portion R on the
outer circumferential surface of the curved part of the outer rim
52A with abrasive cloth/paper 61.
[0085] The support means 62 is equipped with a rotary plate 67
which is rotatably supported by a support tube 66 and a jig plate
68 which is removably and externally fitted and fixed to the rotary
plate 67, in which it is configured to set the outer rim 52A to the
jig plate 68 with a center axis of the rim 52A made substantially
vertical to the jig plate 68 and the superimposed part 52a side
made to be in an upper side, so that the body part 52b extends
downwards from the superimposed part 52a. In addition, it is
configured to support the outer rim 52A of various sizes by the
support means 62 by replacing the jib plate 68 with that of a
different sized outside diameter.
[0086] The rotation drive means 64 is primarily composed of three
holding rollers 63 rotatably installed with a center axes thereof
made in the vertical direction at specified intervals in the
circumferential direction on an outside of the outer rim 52A
supported by the support means 62, an air cylinder 69 which
pressurizes and brings the holding rollers 63 in contact with the
flange part 52c of the outer rim 52A, and an electrically-driven
motor 70, in which the rotation drive means 64 for rotating and
driving one holding roller 63 is configured to rotate the outer rim
52A at low speed by rotating and driving one holding roller 63 with
the rotation drive means 64 in a state that the outer rim 52A is
held by the three holding rollers 63.
[0087] The grinding means 65 is equipped with a drive means 75
which has an electrically-operated motor 72, a plurality of pulleys
73, and a belt 74 stretched between the pulleys 73, and an abrasive
cloth/paper 61 including a flap wheel rotated and driven by the
drive means 75. As the abrasive cloth/paper 61, it is possible to
use those other than the flap wheel. In particular, it is
preferable to use the abrasive cloth/paper 61 which can deform an
outer circumferential surface thereof along a curved surface of the
welding planned portion R, so that plating of the welding planned
portion R can be neatly ground and removed by a single operation.
In addition, this grinding means 65 is configured to be capable of
adjusting a position thereof in such a manner that the abrasive
cloth/paper 61 is pressurized and brought in contact substantially
vertical to the welding planned portion R by an elevating means and
a horizontal moving means not shown.
[0088] In this plating removing apparatus 60, a rotating speed of
the outer rim 52A can be optionally set, but in order to
sufficiently secure the processing capacity and surface properties
of a grinding surface, the rotating speed of the outer rim 52A is
set to be, for example, 5-100 rpm, and a rotating speed of the
abrasive cloth/paper 61 is set to be 1500-3000 rpm, and the
pressurizing contact force of the abrasive cloth/paper 61 with
respect to the outer rim 52A is set to be 0.5 kN-1.5 kN so as to
provide a configuration that the welding planned portion R can be
ground during a single rotation of the outer rim 52A. However, it
is also possible to provide a configuration to complete the
grinding treatment during multiple rotations of the rim 2 or to
divide the grinding treatment into multiple treatments in the axial
direction. A width of the abrasive cloth/paper 61 is preferably set
to be slightly larger than that of the welding planned portion R so
that plating of the welding planned portion R can be ground and
removed by a single grinding treatment.
[0089] When plating is removed by the use of this plating removing
apparatus 60, as shown in FIG. 11(a), the jig plate 68 suitable for
an inside diameter size of the outer rim 52A subjected to a
grinding treatment is set to the rotary plate 67, and then the
outer rim 52A is set with a center axis thereof made substantially
vertical to the jig plate 68, and the superimposed part 52a side
made to be in an upper side in such a manner that the body part 52b
extends downwards from the superimposed part 52a.
[0090] Then, as shown in FIG. 11(b), the holding rollers 63 are
allowed to advance by the air cylinder 69 and an outer
circumferential part of the flange part 52c set to the support
means 62 is held by the three holding rollers 63.
[0091] In this way, in a state that the outer rim 52A is held by
three of the holding rollers 63 of the rotation drive means 64, one
of the holding rollers 63 is rotated and driven by the rotation
drive means 64, thereby the outer rim 52A is rotated and driven at
low speed of, for example, 50 rpm.
[0092] On the other hand, as shown in FIG. 12(a), a vertical
directional position and a longitudinal directional position of the
abrasive means 65 are adjusted in such a manner that the abrasive
cloth/paper 61 faces the welding planned portion R of the outer rim
52A with a subtle clearance provided in accordance with the size of
the outer rim 52A.
[0093] And as shown in FIG. 12(b), while the abrasive cloth/paper
61 is rotated by the electrically-operated motor 72, the abrasive
cloth/paper 61 is pressed and brought in contact with the welding
planned portion R of the outer rim 52A by the pressurizing cylinder
76, so as to grind plating of the welding planned portion R. In
such event, the abrasive cloth/paper 61 is pressed and brought in
contact with a center part in a substantially vertical state, and
an outer circumferential surface of the abrasive cloth/paper 61 is
deformed in such a manner that a center part thereof in the
thickness direction is slightly dented along a curved surface of
the welding planned portion R as shown in FIG. 13, thereby the wide
welding planned portion R is ground at a single time. In addition,
in the welding planned portion R and its vicinity where a grinding
treatment was carried out, as shown in FIG. 14, the base material
area 58a and the plated area 58b of the welding planned portion R
are smoothly linked and no level difference is formed at a boundary
between the base material area 58a and the plated area 58b,
therefore, exfoliation of the plated area 58b can be effectively
prevented.
[0094] In this way, while the outer rim 52A is allowed to make a
single rotation by the rotation drive means 64, and when grinding
of the welding planned portion R is completed, pressurization by
the pressurizing cylinder 76 is stopped to separate the abrasive
cloth/paper 61 from the outer rim 52A, while a rotation of the
abrasive cloth/paper 61 is stopped to reverse the holding roller 63
and remove the ground outer rim 52A which is subjected a grinding
treatment from the jig plate 68, after which a new outer rim 52A is
set to the jig plate 68, and plating of the welding planned portion
R is ground and removed again in the same manner as stated above.
In the present embodiment, while the outer rim 52A is being turned
around to make a single rotation, the welding planned portion R is
successively subjected to a grinding treatment, but the grinding
treatment can be carried out during several rotations or the
welding planned portion R may be divided into multiple portions in
the width direction for the successive grinding.
[0095] In the assembly process, the superimposed portions 52a of
both of the outer rim 52A and the inner rim 52B are superimposed
while an outer circumferential part of the disk 54 is fixed to this
superimposed part 52a with the bolt 53 to integrate both of the
outer rim 52A and the inner rim 52B to the disk 54 into one, after
which the welding planned portions R of both of the outer rim 52A
and the inner rim 52B are successively welded and joined from an
outer circumferential side of the inner rim 52B by TIG welding or
MIG welding, and a three-piece wheel 51 as shown in FIG. 10 is
obtained.
[0096] When plating is provided for the inner rim 52B, as is the
case of the outer rim 52A, using the plating removing apparatus 60,
the welding planned portion R of an outer circumferential surface
of the curved part linked from the superimposed part 52a to the
cylindrical part 52b of the inner rim 52B can be ground.
* * * * *