U.S. patent application number 16/739178 was filed with the patent office on 2020-07-23 for polishing device.
The applicant listed for this patent is HONDA MOTOR CO., LTD.. Invention is credited to Hideaki Imanishi, Daisuke Nakazono, Naoki Takahashi.
Application Number | 20200230777 16/739178 |
Document ID | / |
Family ID | 71608783 |
Filed Date | 2020-07-23 |
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United States Patent
Application |
20200230777 |
Kind Code |
A1 |
Nakazono; Daisuke ; et
al. |
July 23, 2020 |
POLISHING DEVICE
Abstract
A polishing device includes shape following sections opposing a
workpiece with a polishing body interposed between the shape
following sections and the workpiece, and each including a
displaceable shaft section. At least two of the shaft sections
adjacent to each other are coupled via a link member. For example,
when one of the shaft sections of the shape following sections
coupled via the link member retracts by receiving a reaction force
from the workpiece, the other of the shaft sections advances.
Inventors: |
Nakazono; Daisuke; (Hagagun,
JP) ; Takahashi; Naoki; (Hagagun, JP) ;
Imanishi; Hideaki; (Hagagun, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HONDA MOTOR CO., LTD. |
Tokyo |
|
JP |
|
|
Family ID: |
71608783 |
Appl. No.: |
16/739178 |
Filed: |
January 10, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B24B 41/047 20130101;
B24B 29/02 20130101 |
International
Class: |
B24B 29/02 20060101
B24B029/02; B24B 41/047 20060101 B24B041/047 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 21, 2019 |
JP |
2019-007418 |
Claims
1. A polishing device that polishes an object-to-be-polished by an
expandable or contractible polishing body, the polishing device
comprising: a plurality of shape following sections opposing the
object-to-be-polished with the polishing body interposed between
the shape following sections and the object-to-be-polished, and
each including a displaceable shaft section; a supporting body
configured to support the shape following sections; and a link
section configured to couple the shaft sections to each other,
wherein the link section includes a link member configured to
couple at least two of the shaft sections adjacent to each other,
and when one of the two shaft sections coupled via the link member
retracts by receiving a reaction force from the
object-to-be-polished, another of the two shaft sections
advances.
2. The polishing device according to claim 1, wherein the link
section further includes a separate link member configured to
couple the link members to each other.
3. The polishing device according to claim 1, wherein the link
section is provided with a locking unit configured to position and
fix the shaft section.
4. The polishing device according to claim 1, wherein the shape
following sections each include a tip that faces the polishing body
and is provided with a swinging section configured to swing.
5. The polishing device according to claim 1, wherein the shape
following sections each include a tip that faces the polishing body
and is configured to rotate.
6. The polishing device according to claim 1, wherein the plurality
of shape following sections are arranged in a zigzag manner.
7. The polishing device according to claim 1, further comprising an
eccentric rotation unit configured to eccentrically rotate the
supporting body.
8. The polishing device according to claim 1, further comprising a
robot configured to hold the supporting body.
9. The polishing device according to claim 1, wherein the polishing
body is an endless belt configured to turn, and the polishing
device comprises a driving force applying unit configured to apply,
to the endless belt, a driving force for turning.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is based upon and claims the benefit of
priority from Japanese Patent Application No. 2019-007418 filed on
Jan. 21, 2019, the contents of which are incorporated herein by
reference.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The present invention relates to a polishing device that
polishes an object-to-be-polished by a polishing body. Description
of the Related Art
[0003] A polishing body for polishing an object-to-be-polished is
usually configured as a disk-shaped rotating body as exemplified in
Japanese Laid-Open Patent Publication No. 2004-009189. However, in
this case, although it is possible for a flat surface to be
polished, it is not easy for an irregular surface where undulations
are present to be uniformly polished.
[0004] Accordingly, providing the polishing body with an elastic
body (a cushion), for example, a sponge, is envisioned. This is
because in this case, the elastic body is crushed when polishing a
projection of the object-to-be-polished, whereas the crushed
elastic body attempts to return to its original shape when
polishing a recess of the object-to-be-polished. Thus, since a
shape following ability is manifested in the polishing body by the
elastic body, it is conceivably made possible for the irregular
surface to be comparatively easily polished.
SUMMARY OF THE INVENTION
[0005] In fact, the shape following ability of the elastic body is
not particularly favorable. Therefore, in the case where, for
example, regarding a region-to-be-polished having a complex shape
of the kind where a projection and a recess are alternately
aligned, it is attempted to polish the projection of the
region-to-be-polished, the elastic body may sometimes be
insufficiently crushed. When such a situation occurs, a polishing
amount with respect to the projection will be larger than a design
value.
[0006] In order to avoid this, often, when the
region-to-be-polished has a complex shape, polishing is performed
manually by an operator. However, this case is troublesome and a
burden for the operator.
[0007] A main object of the present invention is to provide a
polishing device capable of performing automatic and favorable
polishing, even in such a case as when a region-to-be-polished has
a complex shape.
[0008] According to an embodiment of the present invention, there
is provided a polishing device that polishes an
object-to-be-polished by an expandable or contractible polishing
body, the polishing device comprising:
[0009] a plurality of shape following sections opposing the
object-to-be-polished with the polishing body interposed between
the shape following sections and the object-to-be-polished, and
each including a displaceable shaft section;
[0010] a supporting body configured to support the shape following
sections; and
[0011] a link section configured to couple the shaft sections to
each other, wherein
[0012] the link section includes a link member configured to couple
at least two of the shaft sections adjacent to each other, and
[0013] when one of the two shaft sections coupled via the link
member retracts by receiving a reaction force from the
object-to-be-polished, another of the two shaft sections
advances.
[0014] In the present invention, when the polishing body makes
sliding contact with (performs polishing of) the
object-to-be-polished, the shaft section configuring the shape
following section that opposes the object-to-be-polished via the
polishing body, is displaced. That is, when the shaft section
receives the reaction force from the object-to-be-polished, the
shaft section retracts in a direction of separating from the
object-to-be-polished. Now, the shaft sections adjacent to each
other are coupled via the link member. Hence, the shaft section,
which is adjacent to the shaft section that has retracted, advances
in a direction of approaching the object-to-be-polished. As a
result of the adjacent shaft sections being displaced as above, it
is avoided that the polishing body receives an excessive pressing
force from the shaft sections. It therefore becomes possible for
the polishing body to deform in accordance with a shape of the
object-to-be-polished.
[0015] That is, according to the present invention, since the shaft
section of the shape following section is configured to be
displaceable so as to follow the shape of the
object-to-be-polished, the polishing body deforms in accordance
with the shape of the object-to-be-polished. Therefore, the
polishing body makes sliding contact with the region-to-be-polished
while applying an appropriate and substantially uniform surface
pressure to the region-to-be-polished. This makes it possible for
automatic and favorable polishing to be implemented.
[0016] The above and other objects, features, and advantages of the
present invention will become more apparent from the following
description when taken in conjunction with the accompanying
drawings, in which a preferred embodiment of the present invention
is shown by way of illustrative example.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a schematic overall side view of a polishing
device according to an embodiment of the present invention;
[0018] FIG. 2 is a schematic side view of a polishing mechanism
configuring the polishing device;
[0019] FIG. 3 is a schematic front view of the polishing
mechanism;
[0020] FIG. 4 is a schematic plan view of the polishing
mechanism;
[0021] FIG. 5 is a schematic partial cross-sectional front view of
a shape following mechanism;
[0022] FIG. 6 is a plan view from an endless belt side, of the
polishing mechanism;
[0023] FIG. 7 is a schematic front view selectively showing a
plurality of the shape following sections;
[0024] FIG. 8 is a schematic explanatory drawing showing a movement
locus of the polishing mechanism on a workpiece being an
object-to-be-polished; and
[0025] FIG. 9 is a schematic plan view showing one example of
attitudes of each of link members included in a link section and a
state of displacement of shaft sections, when a recess is present
in a region-to-be-polished.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] A preferred embodiment of a polishing device according to
the present invention will be presented and described in detail
below with reference to the accompanying drawings.
[0027] FIG. 1 is a schematic overall side view of a polishing
device 10 according to the present embodiment. This polishing
device 10 comprises: an articulated robot 12; a polishing mechanism
16 provided to a tip arm 14 configuring the articulated robot 12;
and a control section 20 that controls the articulated robot 12 and
the polishing mechanism 16. Note that the reference symbol 22 in
FIG. 1 indicates a workpiece being an object-to-be-polished. An
automobile body may be cited as a specific example of the workpiece
22.
[0028] The articulated robot 12 includes a rotatable pedestal 24
and a plurality of operating shafts 26. Hence, the articulated
robot 12 is capable of moving the polishing mechanism 16 to a
certain place of the workpiece 22, and displacing the polishing
mechanism 16 along a region-to-be-polished of the workpiece 22.
[0029] As shown in FIGS. 2 and 3, the polishing mechanism 16 is
coupled to the tip arm 14 via a coupling plate 30. A gear holding
plate 32 of narrower width and smaller area compared to the
coupling plate 30 is close to the coupling plate 30. This gear
holding plate 32 is provided with a gear train. Specifically, the
gear train includes: a driving gear 38 provided to a driving shaft
for eccentricity 36 of a motor for eccentric rotation 34 (an
eccentric rotation unit); a first driven gear 40 engaged with the
driving gear 38; and a second driven gear 42 engaged with the first
driven gear 40. The second driven gear 42 is provided with a driven
shaft for eccentricity 44.
[0030] The driving shaft for eccentricity 36 and the driven shaft
for eccentricity 44 are passed through shaft insertion holes (not
illustrated) respectively formed in the gear holding plate 32 and
the coupling plate 30. A first rotating shaft for eccentricity 48
and a second rotating shaft for eccentricity 50 are respectively
coupled, via eccentric joints 46, to tips of the driving shaft for
eccentricity 36 and the driven shaft for eccentricity 44, the tips
being on a side facing the polishing mechanism 16 and projecting
from the coupling plate 30. An eccentric rotation mechanism 52 for
eccentrically rotating the polishing mechanism 16 is configured as
above. Note that an unillustrated bearing is inserted between the
shaft insertion hole and the driving shaft for eccentricity 36 or
driven shaft for eccentricity 44.
[0031] The first rotating shaft for eccentricity 48 and the second
rotating shaft for eccentricity 50 are coupled to a supporting body
60 configuring the polishing mechanism 16. Specifically, as shown
in FIGS. 2-4, the supporting body 60 is configured by combining: a
motor holding wall section 62 whose height is greatest; a first
side wall section 64 that supports a rear surface of the motor
holding wall section 62 and has a region that inclines downwardly
as the first side wall section 64 is separated from the motor
holding wall section 62; a second side wall section 66 whose height
is substantially half that of the motor holding wall section 62;
and a mechanism holding wall section 68 bridged between the first
side wall section 64 and the second side wall section 66. The first
rotating shaft for eccentricity 48 and the second rotating shaft
for eccentricity 50 are coupled to the upper side of the motor
holding wall section 62 among these wall sections. In this case,
the first rotating shaft for eccentricity 48 and the second
rotating shaft for eccentricity 50 are arranged along a
longitudinal direction of the motor holding wall section 62.
[0032] In this way, the tip arm 14 of the articulated robot 12
holds the supporting body 60 configuring the polishing mechanism
16, via the coupling plate 30 and the eccentric rotation mechanism
52. Note that as may be understood from the above, the first side
wall section 64 and the second side wall section 66 have their one
ends coupled to the motor holding wall section 62 and have their
other ends coupled to the mechanism holding wall section 68. The
mechanism holding wall section 68 is separated by a predetermined
distance from the motor holding wall section 62, by the first side
wall section 64 and the second side wall section 66 interposed
between the mechanism holding wall section 68 and the motor holding
wall section 62.
[0033] As shown in FIG. 2, the motor holding wall section 62 is
provided with a motor for turning 72 (a driving force applying
unit). The motor for turning 72 applies, to an endless belt 70 (a
polishing body) configuring the polishing mechanism 16, a driving
force for turning the endless belt 70. The motor for turning 72 is
attached to a position not interfering with the first rotating
shaft for eccentricity 48 and the second rotating shaft for
eccentricity 50, of the motor holding wall section 62. A long
columnar driving pulley 76 is fitted over a driving shaft for
turning 74 of the motor for turning 72. The driving pulley 76
drives the endless belt 70.
[0034] The supporting body 60 is provided with three bearing
sections not illustrated. As shown in FIG. 4, the bearing sections
each axially support in a rotatable manner a supporting shaft 80
provided to a long columnar driven pulley 78. Each of side
peripheral walls of the driven pulleys 78 also drive the endless
belt 70. Due to the driving pulley 76 and the three driven pulleys
78, the endless belt 70 is stretched so as to have a rectangular
shape in planar view.
[0035] The endless belt 70 is formed of a stacked body of an inner
peripheral belt 82 and an outer peripheral belt 84. The inner
peripheral belt 82 is made of a material excelling in wear
resistance, and the outer peripheral belt 84 is made of a material
excelling in polishing performance. Due to the inner peripheral
belt 82 being driven by the driving pulley 76 and the driven
pulleys 78, the outer peripheral belt 84 turns integrally with the
inner peripheral belt 82. The outer peripheral belt 84 makes
sliding contact with the region-to-be-polished of the workpiece
22.
[0036] An exterior tensioner 86 (a tension applying unit) makes
sliding contact with the outer peripheral belt 84. The exterior
tensioner 86 presses the outer peripheral belt 84 toward the inner
peripheral belt 82 side, and thereby applies a tension to the
endless belt 70. The larger the pressing force is, the more the
endless belt 70 is tensioned. As a result, the tension applied to
the endless belt 70 increases. Conversely, when the pressing force
is small, the tension applied to the endless belt 70 is
reduced.
[0037] The mechanism holding wall section 68 supports a plurality
of shape following mechanisms 90 that press the endless belt 70
from the inner peripheral belt 82 side. Next, this shape following
mechanism 90 will be described.
[0038] FIG. 5 is a schematic partial cross-sectional front view
showing one shape following mechanism 90 along the longitudinal
direction thereof. The shape following mechanism 90 includes a
shaft section 92 and a swinging section 94.
[0039] The shaft section 92 is configured from a casing of an air
motor. The shaft section 92 is held in a displaceable manner by the
mechanism holding wall section 68 (refer to FIG. 4), whereby the
shape following mechanism 90 is supported by the mechanism holding
wall section 68.
[0040] One end on a side of separating from the endless belt 70, of
the shaft section 92 is provided with a joint section 96 to which
an unillustrated air supplying tube is connected. On the other
hand, a rotating shaft 100 is exposed from one end on a side of
approaching the endless belt 70. In the shaft section 92, an air
release hole 102 is formed in a vicinity of the rotating shaft 100.
The rotating shaft 100 rotates as compressed air is supplied to an
inside of the shaft section 92 via the air supplying tube and the
joint section 96. Compressed air supplied to the shaft section 92
is released to the atmosphere via the air release hole 102.
[0041] The rotating shaft 100 is covered by a coupling shaft 104,
and the coupling shaft 104 holds a coupling plate 106.
Specifically, the coupling plate 106 has an insertion hole 108
formed therein, and a joint 110 is inserted in the insertion hole
108. The joint 110 has a screw hole formed therein, and a screw
section provided to one end of the coupling shaft 104 is screwed
into the screw hole. Note that regions exposed from the insertion
hole 108, of the joint 110 have screwed onto them a first nut 112
and a second nut 114. Due to this screwing together, dislocation
from the insertion hole 108 of the joint 110 is prevented.
[0042] A stepped holder 120 having a step section is attached to
the coupling plate 106. A tip of the stepped holder 120 has a screw
hole formed therein, and a screw-shaped shaft section 124 of a ball
joint 122 is screwed into the screw hole. Moreover, a separable
swinging cover 130 is screwed with two engaging shaft sections 128
that project from a ball section 126 of the ball joint 122, and the
swinging cover 130 is thereby attached to the engaging shaft
sections 128. The swinging cover 130 is configured as a shape
closely resembling a spherical segment.
[0043] The coupling shaft 104, the coupling plate 106, the stepped
holder 120, the ball joint 122, and the swinging cover 130 rotate
integrally as the rotating shaft 100 rotates. In contrast, the
shaft section 92 never rotates.
[0044] FIG. 6 is a plan view from the endless belt 70 side. As
shown in this FIG. 6, a plurality of the swinging sections 94 are
arranged so as to form: a plurality of columns aligned along a
turning direction of the endless belt 70: and a plurality of rows
aligned along a width direction of the endless belt 70. Moreover,
the swinging section 94 (and shaft section 92) of an arbitrary row
or column is positioned between swinging sections 94 (and shaft
sections 92) of an adjacent row or column. Therefore, the swinging
sections 94 (and shaft sections 92) form a zigzag shape overall.
Note that in order to facilitate understanding of a zigzag
arrangement of the swinging sections 94, a link mechanism 140 is
shown only in the single outermost column in FIG. 6.
[0045] Now, FIG. 7 selectively shows a plurality of (in the
illustrated example, eight) shape following mechanisms 90 included
in an arbitrary column. Hereafter, in order to facilitate
differentiation of the individual shape following mechanisms 90,
they will be assigned reference symbols 90a-90h.
[0046] As may be understood from FIG. 7, the eight shape following
mechanisms 90a-90h are coupled via the link mechanism 140. In more
detail, the link mechanism 140 includes first through fourth small
link members 142a-142d (link members) that individually couple the
adjacent shape following mechanisms 90a, 90b, adjacent shape
following mechanisms 90c, 90d, adjacent shape following mechanisms
90e, 90f, and adjacent shape following mechanisms 90g, 90h. The
first small link member 142a is coupled via a first tilting shaft
144 to each of the shaft sections 92 of the shape following
mechanisms 90a, 90b.
[0047] Similarly, the second small link member 142b is coupled via
the first tilting shaft 144 to each of the shaft sections 92 of the
shape following mechanisms 90c, 90d, and the third small link
member 142c is coupled via the first tilting shaft 144 to each of
the shaft sections 92 of the shape following mechanisms 90e, 90f.
Furthermore, the fourth small link member 142d is coupled via the
first tilting shaft 144 to each of the shaft sections 92 of the
shape following mechanisms 90g, 90h.
[0048] A first medium link member 146a (a separate link member) is
arranged on an outer side of the first small link member 142a and
the second small link member 142b. Intermediate sections in a
longitudinal direction of the first small link member 142a and the
second small link member 142b and each of end sections of the first
medium link member 146a are coupled via second tilting shafts 148.
It is possible for the first small link member 142a and the second
small link member 142b to individually tilt with the second tilting
shafts 148 as fulcrums.
[0049] A second medium link member 146b (a separate link member)
arranged on an outer side of the third small link member 142c and
the fourth small link member 142d also similarly has each of its
end sections coupled to intermediate sections in a longitudinal
direction of the third small link member 142c and the fourth small
link member 142d via the second tilting shafts 148. It is therefore
possible for the third small link member 142c and the fourth small
link member 142d to individually tilt with the second tilting
shafts 148 as fulcrums.
[0050] Furthermore, a large link member 150 (a separate link
member) is arranged on an outer side of the first medium link
member 146a and the second medium link member 146b. Intermediate
sections in a longitudinal direction of the first medium link
member 146a and the second medium link member 146b and each of end
sections of the large link member 150 are coupled via third tilting
shafts 152. That is, it is possible for the first medium link
member 146a and the second medium link member 146b to individually
tilt with the third tilting shafts 152 as fulcrums.
[0051] The first tilting shafts 144, the second tilting shafts 148,
and the third tilting shafts 152 are individually provided with
unillustrated electromagnets. When the electromagnet is energized
under control action of the control section 20, the first tilting
shaft 144, the second tilting shaft 148, or the third tilting shaft
152 is restrained by an electromagnetic force. That is, rotation of
each of the tilting shafts 144, 148, 152 is forcibly stopped. As a
result, tilting of the first through fourth small link members
142a-142d, the first medium link member 146a, the second medium
link member 146b, and the large link member 150 is forcibly
stopped. Thus, the electromagnet is a locking unit for restraining
the first tilting shaft 144, the second tilting shaft 148, or the
third tilting shaft 152.
[0052] Contrarily, when energization of the electromagnet is
stopped, the first tilting shaft 144, the second tilting shaft 148,
or the third tilting shaft 152 is released from restraint of the
electromagnetic force to become rotatable. Hence, the first through
fourth small link members 142a-142d, the first medium link member
146a, the second medium link member 146b, and the large link member
150 attain a tiltable state.
[0053] Although illustration thereof is omitted, when eight or more
shape following mechanisms 90 are included in one column, the link
mechanism 140 similar to that described above is provided also to
the remaining shape following mechanisms 90. Moreover, the same
applies also to another column. Note that the link mechanism 140 is
not provided between an arbitrary single shape following mechanism
90 and a shape following mechanism 90 included in a row adjacent to
this arbitrary single shape following mechanism 90.
[0054] In the above configuration, the control section 20 controls
the motor for eccentric rotation 34, the motor for turning 72, the
exterior tensioner 86, the electromagnets, and an air supplying
mechanism (not illustrated) for performing supply/discharge of
compressed air to/from the air motor.
[0055] The polishing device 10 according to the present embodiment
is basically configured as above, and the operational advantages
thereof will be next described in relation to a control method
(operation) of the polishing device 10.
[0056] In order to move the endless belt 70 along the
region-to-be-polished in a state where the endless belt 70 has been
abutted on a polishing start point of the workpiece 22, teaching is
performed beforehand in the articulated robot 12 so that each of
the shafts rotates or revolves by a predetermined angle. In
addition, the control section 20 selects the shape following
mechanisms 90 that should be supplied with compressed air from the
air supplying mechanism from among the plurality of shape following
mechanisms 90 based on a shape of the workpiece 22, and determines
a timing of that supply.
[0057] For example, when implementing polishing on the workpiece 22
shown in FIG. 8, the polishing mechanism 16 is displaced in order
of a section-A 160.fwdarw.a section-B 162.fwdarw.a section-C
164.fwdarw.a section-D 166 of the workpiece 22. That is, the
section-A 160 is the polishing start point, and the section-D 166
is a polishing end point. In the case where, for example, in the
section-A 160, one column, namely, a lowest column, in the
section-B 162 and the section-C 164, two columns, namely, the
lowest column and a column one above the lowest column, and in the
section-D 166, three columns, namely, the lowest column and columns
one and two above the lowest column, fall outside the
region-to-be-polished, the lowest column does not overlap the
region-to-be-polished from the polishing start point to the
polishing end point. In such a case, compressed air may not be
supplied to the shaft sections 92 of the shape following mechanisms
90 forming the lowest column.
[0058] When starting polishing, the control section 20 first
controls the exterior tensioner 86. Specifically, the exterior
tensioner 86 is displaced so as to approach the endless belt 70,
and presses the endless belt 70. Due to this pressing, the endless
belt 70 is tensioned so that the tension thereof increases. In
addition, the control section 20 supplies compressed air from the
air supplying mechanism. The compressed air is introduced into the
shaft section 92 (the casing) via the air supplying tube and the
joint section 96. As a result, the rotating shaft 100 configuring
the air motor rotates, and, moreover, the coupling shaft 104, the
coupling plate 106, the stepped holder 120, the ball joint 122, and
the swinging cover 130 integrally rotate.
[0059] After the operating shafts 26 of the articulated robot 12
have each suitably operated, and the endless belt 70 has abutted on
the section-A 160, the control section 20 drives the motor for
eccentric rotation 34 and the motor for turning 72. In association
with the rotation of the driving shaft for eccentricity 36 of the
motor for eccentric rotation 34, the driving gear 38 rotates, and
the first driven gear 40 (refer to FIGS. 2 and 3) engaged with the
driving gear 38 and the second driven gear 42 engaged with the
first driven gear 40, rotate. Following this, the driven shaft for
eccentricity 44 also rotates.
[0060] As described above, the first rotating shaft for
eccentricity 48 and the second rotating shaft for eccentricity 50
are respectively coupled, via the eccentric joints 46, to the
driving shaft for eccentricity 36 and the driven shaft for
eccentricity 44. Hence, the first rotating shaft for eccentricity
48 and the second rotating shaft for eccentricity 50 move with loci
of circles centered on respective rotation centers of the driving
shaft for eccentricity 36 and the driven shaft for eccentricity 44.
As a result, the polishing mechanism 16, in which the first
rotating shaft for eccentricity 48 and the second rotating shaft
for eccentricity 50 are coupled to the supporting body 60,
eccentrically rotates.
[0061] Moreover, when the motor for turning 72 is driven, the
driving shaft for turning 74 and the driving pulley 76 (refer to
FIG. 4) rotate. Therefore, the endless belt 70 pulled by the
driving pulley 76 begins to turn. Turning of the endless belt 70 is
assisted by the three driven pulleys 78. That is, in this case, the
endless belt 70 turns due to the driving pulley 76 and the three
driven pulleys 78, while being applied with tension by the exterior
tensioner 86 and being pressed by the shape following mechanism 90
(the swinging cover 130) from the inner peripheral belt 82
side.
[0062] Due to the above eccentric rotation of the polishing
mechanism 16 and turning of the endless belt 70, polishing of the
section-A 160 is started. That is, the endless belt 70 makes
sliding contact with the section-A 160, thereby polishing the
section-A 160. Since the swinging cover 130 which is rotating is
abutting on the endless belt 70, the endless belt 70 receives a
pressing force from the shape following mechanism 90 to be pressed
against the section-A 160. Moreover, the endless belt 70 makes
sliding contact over the section-A 160 with sufficient surface
pressure, while eccentrically rotating integrally with the
supporting body 60. By a combination of rotation of the swinging
cover 130 and turning and eccentric rotation of the endless belt
70, the section-A 160 is favorably polished.
[0063] Moreover, the plurality of shape following mechanisms 90 are
disposed in a zigzag manner. In this case, the plurality of shape
following mechanisms 90 come close to each other more densely
compared to when the shape following mechanisms 90 are disposed on
the same axis. Hence, the section-A 160 (the region-to-be-polished)
can be evenly polished. Thus, the shape following mechanisms 90
disposed in a zigzag manner complement each other's range of
polishing.
[0064] In this state, the control section 20 operates each of the
operating shafts 26 of the articulated robot 12 in such a manner
that the polishing mechanism 16 moves to the section-D 166 through
the section-B 162 and the section-C 164. Note that in the course of
the polishing mechanism 16 moving, the shaft sections 92 of the
shape following mechanisms 90 positioned outside the
region-to-be-polished do not undergo supply of compressed air.
[0065] Incidentally, projections 170a, 170b or a recess 172 sunken
relatively with respect to the projections 170a, 170b are assumed
to be present in the workpiece 22, as shown in FIG. 9. In this
case, the shape following mechanisms 90b, 90c, 90e, 90f, 90g
positioned above the projections 170a, 170b receive a reaction
force from the projections 170a, 170b to be displaced in a
direction of separating from the projections 170a, 170b.
[0066] At this time, the first through fourth small link members
142a-142d tilt with the first tilting shafts 144 as fulcrums, and,
depending on a degree of protrusion of the projections 170a, 170b,
the second medium link member 146b tilts with the second tilting
shafts 148 as fulcrums. Furthermore, the large link member 150
tilts with the third tilting shafts 152 as fulcrums. Due to this
tilting, the shape following mechanisms 90a, 90d, 90h opposing the
recess 172 are displaced in a direction of approaching the recess
172.
[0067] Moreover, the swinging covers 130 configuring the shape
following mechanisms 90a-90h swing in accordance with the shape of
the region-to-be-polished or inclination angles of the projections
170a, 170b. For the above reason, abutting on the endless belt 70,
of the swinging covers 130 configuring the shape following
mechanisms 90a-90h is maintained, regardless of the shape of the
workpiece 22 or the inclination angles of the projections 170a,
170b. Therefore, deformation of the endless belt 70 is never
hindered. Hence, the region-to-be-polished can be favorably
polished, regardless of the shape of the region-to-be-polished.
[0068] Thus, in the present embodiment, the first through fourth
small link members 142a-142d, the first medium link member 146a,
the second medium link member 146b, and the large link member 150
that configure the link mechanism 140 suitably tilt in accordance
with the shape of the workpiece 22 from the polishing start point
(the section-A 160) to the polishing end point (the section-D 166).
Due to this tilting, the shaft section 92 configuring the shape
following mechanism 90 is displaced in a direction of approaching
the workpiece 22 or in a direction of separating from the workpiece
22. As a result, the endless belt 70 changes following the shape of
the workpiece 22. Hence, polishing of the workpiece 22 by the
polishing mechanism 16 can be favorably continued. Note that when a
place not requiring polishing is present even in the
region-to-be-polished, those of the shape following mechanisms 90
that oppose the place not requiring polishing may not be supplied
with compressed air.
[0069] For example, when the projections 170a, 170b and the recess
172 are present over a long distance, the shaft sections 92 may be
positioned and fixed. In this case, the control section 20 performs
energization of the electromagnets provided to each of the first
tilting shafts 144, the second tilting shafts 148, and the third
tilting shafts 152. As described above, restraint of the
electromagnetic force generated along with this energization
hinders further rotation of the first tilting shafts 144, the
second tilting shafts 148, and the third tilting shafts 152, and,
consequently, further tilting of the first through fourth small
link members 142a-142d, the first medium link member 146a, the
second medium link member 146b, and the large link member 150.
Hence, the shaft sections 92 are brought into a locked state of
being positioned and fixed. In other words, positions of the shaft
sections 92 become constant. Since, as a result, a state of the
swinging covers 130 having abutted on the endless belt 70 is
maintained, the workpiece 22 can be favorably polished.
[0070] In order to release the locked state, energization of the
electromagnets should be stopped. The electromagnetic force thereby
disappears, so each of the first tilting shafts 144, the second
tilting shafts 148, and the third tilting shafts 152 is released
from restraint of the electromagnetic force to become rotatable. As
a result, the first through fourth small link members 142a-142d,
the first medium link member 146a, the second medium link member
146b, and the large link member 150 become tiltable.
[0071] There is no particular need for locking by the electromagnet
to be performed simultaneously on all of the first tilting shafts
144, the second tilting shafts 148, and the third tilting shafts
152. That is, only the electromagnets provided to tilting shifts
needing to be locked should undergo energization and be
activated.
[0072] Although FIG. 9 shows the projections 170a, 170b or recess
172 in an exaggerated manner, the actual degree of protrusion of
the projections 170a, 170b is at most several tens of micrometers,
and a depth of the recess 172 is also of the same degree.
[0073] When the polishing mechanism 16 reaches the section-D 166,
rotation or revolution of each of the operating shafts 26 of the
articulated robot 12 stops, and movement of the polishing mechanism
16 ends. At this time, the control section 20 stops both the motor
for eccentric rotation 34 and the motor for turning 72, whereby
eccentric rotation of the polishing mechanism 16 and turning of the
endless belt 70 are stopped.
[0074] As indicated above, according to the present embodiment,
polishing can be performed automatically by the polishing device
10. Therefore, a burden of the operator is reduced.
[0075] Moreover, as described above, the endless belt 70 is
turning, so an unspecific place of the outer peripheral belt 84
makes sliding contact with the region-to-be-polished. In other
words, it is avoided that a specific place alone of the outer
peripheral belt 84 is involved in polishing. Therefore, the outer
peripheral belt 84 is not easily worn down. Hence, the same outer
peripheral belt 84 can be employed over a long time, even when the
above-described polishing is repeated. Note that when the outer
peripheral belt 84 has worn down due to repeated polishing over a
long time, and polishing accuracy has lowered, the outer peripheral
belt 84 should be replaced with a new one.
[0076] The present invention is not particularly limited to the
above-described embodiment, and may be variously modified in a
range not departing from the spirit of the present invention.
[0077] For example, a sheet body may be stretched to configure the
polishing body, instead of the endless belt 70.
[0078] Furthermore, polishing may be performed similarly to above
except that the motor for eccentric rotation 34 is not operated (in
other words, except that the polishing mechanism 16 is not
eccentrically rotated). Also in this case, sufficient polishing is
performed. As may be understood from this, the eccentric rotation
unit, such as the motor for eccentric rotation 34, is not
indispensable.
[0079] Moreover, a link mechanism omitting any of the first medium
link member 146a, the second medium link member 146b, or the large
link member 150, may be provided. When the large link member 150 is
present in plurality, a further separate link member coupling these
large link members 150 may be provided.
* * * * *