U.S. patent application number 14/272757 was filed with the patent office on 2014-09-04 for robot.
This patent application is currently assigned to Seiko Epson Corporation. The applicant listed for this patent is Seiko Epson Corporation. Invention is credited to Yasuhisa HIRATA, Tatsuya HOSODA, Kazuhiro KOSUGE, Yukihiro YAMAGUCHI.
Application Number | 20140249677 14/272757 |
Document ID | / |
Family ID | 45807474 |
Filed Date | 2014-09-04 |
United States Patent
Application |
20140249677 |
Kind Code |
A1 |
YAMAGUCHI; Yukihiro ; et
al. |
September 4, 2014 |
ROBOT
Abstract
A robot includes a gripping section and a main body section to
which the pair of finger sections are attached, having one end
sections of the pair of finger sections rotatably connected to each
other around a first rotating shaft disposed at a position separate
from the main body section, and adapted to open and close the pair
of finger sections by swinging the other side of the pair of finger
sections on a plane parallel to a mounting surface on which an
object is mounted centered on the first rotating shaft to thereby
grip the object, a moving device adapted to relatively move the
object and the gripping section, and a control device adapted to
control the moving device to move the gripping section relatively
toward the object, and grip the object with the gripping section at
at least three contact points.
Inventors: |
YAMAGUCHI; Yukihiro;
(Sendai, JP) ; HOSODA; Tatsuya; (Chino, JP)
; KOSUGE; Kazuhiro; (Sendai, JP) ; HIRATA;
Yasuhisa; (Sendai, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Seiko Epson Corporation |
Tokyo |
|
JP |
|
|
Assignee: |
Seiko Epson Corporation
Tokyo
JP
|
Family ID: |
45807474 |
Appl. No.: |
14/272757 |
Filed: |
May 8, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13232273 |
Sep 14, 2011 |
|
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14272757 |
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Current U.S.
Class: |
700/259 ;
294/106; 700/260 |
Current CPC
Class: |
B25J 9/1633 20130101;
Y10S 901/31 20130101; B25J 15/0206 20130101; B25J 15/08 20130101;
B25J 9/1697 20130101; Y10S 901/41 20130101; Y10S 901/30 20130101;
Y10T 74/18952 20150115 |
Class at
Publication: |
700/259 ;
294/106; 700/260 |
International
Class: |
B25J 15/08 20060101
B25J015/08; B25J 9/16 20060101 B25J009/16 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 15, 2010 |
JP |
2010-206662 |
Claims
1. A robot comprising: a body section; a first finger section
attached to the body section, and is able to rotate around a
rotating axis which is not on the body section; and a second finger
section attached to the body section; and is able to rotate around
a rotating axis which is not on the body section.
2. The robot according to claim 1 wherein at least one of the first
finger section and the second finger section has contact with an
object at at least two contact points when the object is gripped by
the first finger section and the second finger section.
3. The robot according to claim 1 wherein an object is able to
gripped by making the object have contact with the first finger
section, the second finger section and the body section.
4. The robot according to claim 1 wherein at least one of the first
finger section and the second finger section has a guard to prevent
an object from jumping out in a direction perpendicular to a
mounting surface which the object is mounted.
5. The robot according to claim 1 wherein each of the first finger
section and the second finger section includes a first link section
having one end which is able to rotate around the rotating axis
which is not on the body section, and a second link section having
one end which is able to rotate around a rotating axis on the body
section, and the other end rotatably attached to the other end of
the first link section.
6. The robot according to claim 5 wherein a position of the
rotating axis on the body section moves along a straight line
connecting the rotating axis which is not on the body section and
the rotating axis on the body section in a direction opposite to a
direction toward the rotating axis which is not on the body section
as the first finger section and the second finger section move in a
closing direction.
7. The robot according to claim 1 comprising: a camera taking a
picture of an object, and a control device detecting a position of
the object based on a result of taking a picture by the camera, and
then controlling the first finger section and the second finger
section to move toward the object.
8. The robot according to claim 7 wherein the camera is attached to
the body section.
9. The robot according to claim 7 wherein each of the first finger
section and the second finger section includes a tip section
disposed in parallel to a mounting surface which an object is
mounted, and is able to grip the object, and a base end section
disposed in a direction of getting apart from the mounting surface,
and attached to the body section.
10. The robot according to claim 9 wherein the tip section of each
of the first finger section and the second finger section has a
flat surface opposed to the mounting surface.
11. The robot according to claim 9 wherein the tip section and the
base end section are arranged so as to eliminate an overlap between
the tip section and the base end section in a view from a direction
in which the camera takes a picture of the one end section.
12. The robot according to claim 9 wherein an angle formed between
the tip section and the base end section is an obtuse angle.
13. The robot according to claim 1 comprising: a detection device
detecting a force for gripping an object, and a control device
controlling the first finger section and the second finger section
based on a detection result of the detection device.
14. The robot according to claim 1 wherein a rotating axis of the
first finger section and a rotating axis of the second finger
section are the same.
15. The robot according to claim 1 wherein an attachment position
of the first finger section which is attached to the body section
is movable along a circular arc, and an attachment position of the
second finger section which is attached to the body section is
movable along a circular arc.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation patent application of U.S.
application Ser. No. 13/232,273 filed Sep. 14, 2011, which claims
priority to Japanese Patent Application No. 2010-206662, filed Sep.
15, 2010, all of which are expressly incorporated by reference
herein in their entireties.
BACKGROUND
[0002] 1. Technical Field
[0003] The present invention relates to a robot.
[0004] 2. Related Art
[0005] In the past, vertical articulated robots, horizontal
articulated robots (scalar robots), Cartesian coordinate robots,
and so on have been developed as industrial robots, and are
selected in accordance with purposes suitable for the features
thereof. In such robots, a gripping section for gripping the object
is moved to a target position, and then the gripping section is
made to grip the object.
[0006] Such industrial robots are required to effectively grab the
object, which takes a variety of unspecified postures, in a
predetermined posture in working processes such as an automatic
assembly process. For example, in the robot described in
JP-A-2009-78312 (Document 1), it is arranged that a chuck mechanism
for gripping the object can be rotated by a rotation mechanism in
forward and reverse directions around the center shaft for
supporting the chuck itself, and further, the rotation mechanism
itself can pivot within a predetermined downward angle range with a
pivot mechanism.
[0007] According to the technology of Document 1, since the control
device controls the rotation mechanism and the pivot mechanism, it
is conceivable that the chuck can be oriented toward a variety of
directions, and the object in a variety of postures can be gripped
with the chuck mechanism due to the control of the control
device.
[0008] However, if the object is, for example, small-sized and
lightweight, it becomes difficult to accurately detect the position
and the posture of the object using a camera, and accurate
positioning of the chuck mechanism for gripping the object is not
achievable in some cases. If the accurate positioning of the chuck
mechanism is not achievable, the object and the chuck mechanism
might have contact with each other at an unintended place during
the gripping operation. On that occasion, since the object is
lightweight, the object moves in an unintended direction, and there
arises a problem that it is not achievable to hold the object at a
desired position or a problem that the object jumps out of the
gripping space.
SUMMARY
[0009] An advantage of some aspects of the invention is to provide
a robot capable of reliably gripping the object at a predetermined
position without failing to catch the object.
[0010] An aspect of the invention is directed to a robot including
a gripping section having a pair of finger sections and a main body
section to which the pair of finger sections are attached, having
one end sections of the pair of finger sections rotatably connected
to each other around a first rotating shaft disposed at a position
separate from the main body section, and adapted to open and close
the pair of finger sections by swinging the other end side of the
pair of finger sections on a plane parallel to a mounting surface
on which an object is mounted centered on the first rotating shaft
to thereby grip the object, a moving device adapted to relatively
move the object and the gripping section, and a control device
adapted to control the moving device to move the gripping section
relatively toward the object, and dispose the pair of finger
sections in a periphery of the object, and then control the
gripping section to open and close the pair of finger sections in a
plane parallel to the mounting surface, pinch the object between
the pair of finger sections from a lateral side of the object, and
grip the object with the gripping section at at least three contact
points.
[0011] According to the robot described above, since the pair of
finger sections are moved to the periphery of the object and then
opened and closed in the plane parallel to the mounting surface on
which the object is mounted due to the control by the control
device, it results that the periphery of the object is surrounded
by the pair of finger sections. Thus, the object is prevented from
jumping out of the area surrounded by the pair of finger sections.
Further, since the pair of finger sections pinch the object from
the lateral side thereof, the object moves with the operation of
the pair of finger sections, and thus the position is adjusted.
Further, since the gripping section grips the object at at least
three contact points, it is possible to restrict the position of
the object and to grip the object stably with the friction at the
contact points. According to such an operation of the gripping
section as described above, the object can be gripped at a
predetermined position. Therefore, it is possible to provide the
robot capable of preventing the object from escaping, and reliably
gripping the object at a predetermined position. Further, since the
pair of finger sections are opened and closed in response to the
swing of the other end side of the pair of finger sections taking
the one end sections of the pair of finger sections as the center
of the rotation, it becomes easy to grip the object even in the
case, for example, in which the object is disposed in a small
area.
[0012] The robot of the above aspect of the invention may be
configured such that at least one of the pair of finger sections
has contact with the object at at least two contact points on a
gripping surface adapted to grip the object from the lateral
side.
[0013] By thus increasing the contact points, it becomes easy to
grip the object stably at a predetermined position.
[0014] The robot of the above aspect of the invention may be
configured such that the gripping section is provided with a main
body section to which the pair of finger sections are coupled, and
grips the object at at least three contact points by making the
object have contact with the pair of finger sections and the main
body section.
[0015] The robot of the above aspect of the invention may be
configured such that at least one of the pair of finger sections
has a guard adapted to prevent the object from jumping out in a
direction perpendicular to the mounting surface, the guard being
disposed on an opposite side to the mounting surface across the
object.
[0016] According to the robot of the configuration, it is possible
to prevent the object from jumping out upward when pinching the
object.
[0017] The robot of the above aspect of the invention may be
configured such that each of the pair of finger sections includes a
first link section having one end rotatably coupled to the first
rotating shaft, and a second link section having one end rotatably
coupled to a second rotating shaft provided to the main body
section, and the other end rotatably coupled to the other end of
the first link section.
[0018] By thus increasing the link sections, it becomes easy to
grip the object stably at a predetermined position.
[0019] The robot of the above aspect of the invention may be
configured such that a position of the second rotating shaft moves
along a straight line connecting the first rotating shaft and the
second rotating shaft in a direction opposite to a direction toward
the first rotating shaft as the pair of finger sections move in a
closing direction.
[0020] According to the robot of the configuration, it is possible
to arrange that the object hardly moves with the closing operation
of the pair of finger sections. Therefore, it becomes easy to grip
the object stably at a predetermined position.
[0021] The robot of the above aspect of the invention may be
configured such that a camera adapted to take a picture of the
object is further provided, and the control device detects a
position of the object based on a result of taking a picture by the
camera, and then controls the moving device to move the gripping
section relatively toward the object.
[0022] According to the robot of the configuration, the accurate
positioning of the gripping section for gripping the object can be
performed.
[0023] The robot of the above aspect of the invention may be
configured such that the gripping section is provided with a main
body section to which the pair of finger sections are coupled, and
the camera is attached to the main body section.
[0024] According to the robot of the configuration, since the
camera is disposed at a position near to the pair of finger
sections, it is possible to perform accurate positioning of the
pair of finger sections for gripping the object.
[0025] The robot of the above aspect of the invention may be
configured such that each of the pair of finger sections includes a
tip section disposed in parallel to the mounting surface, and
adapted to grip the object, and a base end section disposed in a
direction of getting apart from the mounting surface, and coupled
to the main body section.
[0026] In the case of gripping the object mounted on the mounting
surface, by making the pair of finger sections have contact with
the mounting surface while making the pair of finger sections
perform the gripping operation, it becomes easy to stably grip the
object. If there is adopted the configuration, for example, in
which the tip section and the base end section are arranged in
parallel to each other in the pair of finger sections, the main
body section and the mounting surface have contact with each other
when gripping the object, and the tip section and the mounting
surface become distant from each other to thereby make it difficult
to stably grip the object. However, according to the configuration,
it becomes easy to make the tip sections of the pair of finger
sections have contact with the mounting surface. Therefore, it
becomes easy to grip the object stably at a predetermined
position.
[0027] The robot of the above aspect of the invention may be
configured such that the tip section of each of the pair of finger
sections has a flat surface opposed to the mounting surface.
[0028] According to the robot of the configuration, it becomes easy
to make the tip sections of the pair of finger sections have
contact with the mounting surface compared to the configuration in
which the surface of the tip section of each of the pair of finger
sections opposed to the mounting surface is an uneven surface.
Therefore, it becomes easy to grip the object stably at a
predetermined position.
[0029] The robot of the above aspect of the invention may be
configured such that the tip section and the base end section are
arranged so as to eliminate an overlap between the tip section and
the base end section in a view from a direction in which the camera
takes a picture of the tip section.
[0030] According to the robot of the configuration, it is possible
to perform the gripping operation while checking the gripping
operation of the tip sections.
[0031] The robot of the above aspect of the invention may be
configured such that the angle formed between the tip section and
the base end section is an obtuse angle.
[0032] If there is adopted a configuration, for example, in which
the angle formed between the tip section and the base end section
is an acute angle, there is a possibility that the tip section is
shaded by the base end section when viewed from the direction in
which the image of the one end section is taken by the camera, and
it becomes difficult to detect the accurate gripping operation of
the one end sections. However, according to the configuration, the
tip sections are hardly shaded by the base end sections viewed from
the direction in which the image of the tip sections is taken by
the camera. Therefore, it becomes easy to perform the gripping
operation while checking the gripping operation of the tip
sections.
[0033] The robot of the above aspect of the invention may be
configured such that the gripping section includes a detection
device adapted to detect a force for gripping the object, and the
control device controls the force of the gripping section for
gripping the object based on a detection result of the detection
device.
[0034] According to the robot of the configuration, the gripping
force of the gripping section can be controlled so as not to apply
an excessive load to the object. Therefore, it becomes possible to
prevent the object from being deformed or damaged when gripping the
object.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] The invention will be described with reference to the
accompanying drawings, wherein like numbers reference like
elements.
[0036] FIG. 1 is a perspective view showing a schematic
configuration of a robot according to a first embodiment of the
invention.
[0037] FIGS. 2A and 2B are diagrams showing a configuration of a
gripping section according to the first embodiment.
[0038] FIGS. 3A through 3D are plan views showing an operation of
the gripping section according to the first embodiment.
[0039] FIG. 4 is a flowchart showing an operation of the robot
according to the first embodiment.
[0040] FIGS. 5A and 5B are diagrams showing a configuration of a
gripping section according to a second embodiment of the
invention.
[0041] FIGS. 6A through 6D are plan views showing an operation of
the gripping section according to the second embodiment.
[0042] FIGS. 7A and 7B are diagrams showing a configuration of a
gripping section according to a third embodiment of the
invention.
[0043] FIGS. 8A and 8B are diagrams showing a condition of the
gripping section according to the third embodiment gripping the
object.
[0044] FIGS. 9A and 9B are diagrams showing a configuration of a
gripping section according to a fourth embodiment of the
invention.
[0045] FIGS. 10A and 10B are plan views showing a configuration of
a gripping section according to a fifth embodiment of the
invention.
[0046] FIGS. 11A and 11B are diagrams showing a first modified
example of the gripping section.
[0047] FIGS. 12A through 12D are diagrams showing a second modified
example of the gripping section.
[0048] FIG. 13 is a diagram showing a third modified example of the
gripping section.
[0049] FIG. 14 is a diagram showing a fourth modified example of
the gripping section.
[0050] FIGS. 15A and 15B are diagrams showing a fifth modified
example of the gripping section.
[0051] FIGS. 16A through 16C are plan views respectively showing
sixth through eighth modified examples of the gripping section.
[0052] FIG. 17 is a diagram showing a relationship between the
forces caused when gripping the object with the gripping
section.
DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0053] Hereinafter, some embodiments of the invention will be
described with reference to the accompanying drawings. Each
embodiment shows an aspect of the invention, but does not limit the
scope of the invention, and can arbitrarily be modified within a
technical concept of the invention. Further, in the drawings
explained hereinafter, in order for making each constituent easy to
understand, the actual structures and the structures of the
drawings are different from each other in scale size, number, and
so on.
[0054] In the explanation described below, the XYZ Cartesian
coordinate system shown in FIG. 1 is set, and each of the members
will be explained with reference to the XYZ Cartesian coordinate
system. In the XYZ Cartesian coordinate system, the X axis and the
Y axis are set in parallel to a horizontal plane and perpendicular
to each other, and the Z axis is set in a direction (a vertical
direction) perpendicular to both of the X axis and the Y axis.
First Embodiment
[0055] FIG. 1 is a perspective view showing a schematic
configuration of a robot 1 according to a first embodiment of the
invention. In FIG. 1, the reference symbol W1 denotes a first
object and the reference symbol W2 denotes a second object.
Further, the reference symbol L1A denotes a rotational axis of a
first arm 21A, the reference symbol L2A denotes a rotational axis
of a second arm 22A, the reference symbol L3A denotes a rotational
axis of a third arm 23A, and the reference symbol L4A denotes a
rotational axis of a gripping section 10A. The reference symbol L1B
denotes a rotational axis of a first arm 21B, the reference symbol
L2B denotes a rotational axis of a second arm 22B, the reference
symbol L3B denotes a rotational axis of a third arm 23B, and the
reference symbol L4B denotes a rotational axis of a gripping
section 10B.
[0056] Here, it is assumed that the explanation will be presented
exemplifying the first object W1 by a small-sized lightweight gear,
and exemplifying the second object W2 by an electronic device
provided with a support shaft (a pin) for rotatably supporting the
gear. It should be noted that the first object W1 has a roughly
columnar shape having a curved surface on the side having contact
with the gripping section.
[0057] As shown in FIG. 1, the robot 1 according to the present
embodiment is provided with the gripping sections 10A, 10B for
gripping the object by opening and closing a pair of finger
sections, the arms (moving device) 20A, 20B for relatively moving
the objects and the gripping sections 10A, 10B, conveyer belts 33,
34 for conveying the first object W1, a feeder 36 for carrying the
first object W1 on the first conveyer belt (moving device) 33, a
stage 37 forming a pedestal used for transferring the first object
W1, a stage (moving device) 30 for mounting the objects W1, W2, a
base 50 for supporting the arms 20A, 20B and the stage 30, cameras
40A, 40B attached respectively to the arms 20A, 20B, a control
device 60 for controlling the operation of the robot 1 itself, and
an input device 70 for performing instruction input to the control
device 60.
[0058] The gripping section 10A is coupled to an end section of the
third arm 23A. The gripping section 10A grips the first object W1
disposed on the first conveyer belt 33. The gripping section 10A
conveys the first object W1 thus gripped to the stage 37. The
gripping section 10A is provided with a detection device 41A for
detecting the force used for gripping the first object W1. As the
detection device 41A, there can be used, for example, a pressure
sensor, or a sensor for detecting the variation in the torque of an
electric motor (the variation in the current flowing through the
electric motor).
[0059] The gripping section 10B is coupled to an end section of the
third arm 23B. The gripping section 10B grips the first object W1
disposed on the stage 37. The gripping section 10B conveys the
first object W1 thus gripped to the stage 30. The gripping section
10B conveys the first object W1 thus gripped (or disposed on the
stage 37) to the second object W2. Specifically, the gripping
section 10B inserts the pin of the electronic device W2 into the
gear W1. The gripping section 10B is provided with a detection
device 41B for detecting the force used for gripping the first
object W1. As the detection device 41B, there can be used, for
example, a pressure sensor, or a sensor for detecting the variation
in the torque of an electric motor (the variation in the current
flowing through the electric motor).
[0060] The arm 20A has the first arm 21A, the second arm 22A, and
the third arm 23A coupled in this order, and the first arm 21A is
coupled to the base 50 via a main shaft 24 having a rotational axis
in the Z-axis direction and a bottom section 25 having a roughly
rectangular planar shape. The first arm 21A is disposed rotatably
in forward and reverse directions around the rotational axis L1A in
a horizontal direction (the direction parallel to the X-Y plane) at
the joining section with the main shaft 24. The second arm 22A is
disposed rotatably in forward and reverse directions around the
rotational axis L2A in the horizontal direction at the joining
section with the first arm 21A. The third arm 23A is disposed
rotatably in forward and reverse directions around the rotational
axis L3A in the horizontal direction and movably in up and down
directions (vertical directions (the Z-axis directions)) at the
joining section with the second arm 22A. It should be noted that
the gripping section 10A is disposed rotatably in forward and
reverse directions around the rotational axis L4A in a direction
perpendicular to the horizontal direction at the joining section
with the third arm 23A.
[0061] The arm 20B has the first arm 21B, the second arm 22B, and
the third arm 23B coupled in this order, and the first arm 21B is
coupled to the base 50 via the main shaft 24 having the rotational
axis in the Z-axis direction and the bottom section 25 having a
roughly rectangular planar shape. The first arm 21B is disposed
rotatably in forward and reverse directions around the rotational
axis L1B in the horizontal direction (the direction parallel to the
X-Y plane) at the joining section with the main shaft 24. The
second arm 22B is disposed rotatably in forward and reverse
directions around the rotational axis L2B in the horizontal
direction at the joining section with the first arm 21B. The third
arm 23B is disposed rotatably in forward and reverse directions
around the rotational axis L3B in the horizontal direction and
movably in up and down directions (vertical directions (the Z-axis
directions)) at the joining section with the second arm 22B. It
should be noted that the gripping section 10B is disposed rotatably
in forward and reverse directions around the rotational axis L4B in
a direction perpendicular to the horizontal direction at the
joining section with the third arm 23B.
[0062] The first conveyer belt 33 and the second conveyer belt 34
are disposed distant from the side, on which the arm 20A is
disposed, in this order. The feeder 36 is disposed on the upstream
side (+Y-direction side) of the first conveyer belt 33. The second
conveyer belt 34 is arranged to be larger in size than the first
conveyer belt 33 in a plan view so as to project toward the
downstream direction (-Y-direction side) of the first conveyer belt
33. The first object W1 dropped from the first conveyer belt 33 is
conveyed by the second conveyer belt 34 and is then thrown in an
opening section 36a of the feeder 36 by a tilted conveyer belt not
shown. It is arranged that the first object W1 having failed to be
gripped by the gripping section 10A is circulated through the first
conveyer belt 33, the second conveyer belt 34, and the feeder 36 in
such a manner as described above.
[0063] The stage 30 is provided with a top plate 31 for mounting
the objects, and a base section 35 for supporting the top plate 31.
The base section 35 houses, for example, a moving mechanism for
translating the top plate 31 in the X-axis direction and a moving
mechanism for moving the top plate 31 in the Y-axis direction
independently from each other, and is disposed so as to be able to
move the top plate 31 in the horizontal directions.
[0064] The camera 40A is attached to an end section of the second
arm 22A constituting the arm 20A. As the camera 40A, for example, a
CCD camera is used. The camera 40A takes the picture of the first
object W1 mounted on the first conveyer belt 33. The shot image of
the camera 40A is transmitted to the control device 60.
[0065] The camera 40B is attached to an end section of the second
arm 22B constituting the arm 20B. As the camera 40B, for example, a
CCD camera is used. The camera 40B takes the picture of the first
object W1 and the second object W2 mounted on the to plate 31. The
shot image of the camera 40B is transmitted to the control device
60.
[0066] The control device 60 incorporates a memory, a CPU, a power
supply circuit, and so on. The control device 60 stores, for
example, an operation program for defining the operation content of
the robot 1 input from the input device 70, and starts up a variety
of programs stored in the memory by the CPU to thereby perform the
overall control of the robot 1.
[0067] FIGS. 2A and 2B are diagrams showing a configuration of the
gripping section 10A according to the first embodiment. FIG. 2A is
a plan view showing the configuration of the gripping section 10A
according to the first embodiment. FIG. 2B is a cross-sectional
view along the line A-A shown in FIG. 2A. Here, a configuration of
the gripping section will be explained showing the gripping section
10A out of the gripping sections 10A, 10B as an example. Since the
gripping section 10B has substantially the same configuration as
that of the gripping section 10A, the detailed explanation thereof
will be omitted.
[0068] As shown in FIGS. 2A and 2B, the gripping section 10A is
provided with a main body section 11 and a pair of finger sections
12. One end sections 14 of the pair of finger sections 12 are
coupled to each other rotatably around a first rotating shaft
(rotational axis) 13 provided at a position separate from the main
body section 11. The gripping section 10A is arranged to open and
close the pair of finger sections 12 by swinging the other end side
(here the other end sections 15) of the pair of finger sections 12
in a plane parallel to the surface (the upper surface of the first
conveyer belt 33) 33a on which the first object W1 is mounted
centered on the first rotating shaft 13. It should be noted that in
the explanation below, the surface (the upper surface of the first
conveyer belt 33) on which the first object W1 is mounted is
referred to simply as a "mounting surface" in some cases.
[0069] The main body section 11 is formed so that the side (the
+Y-direction side) on which the pair of finger sections 12 are
disposed is curved. The main body section 11 is provided with an
opening section 11a having a circular arc shape along the curved
portion. The other end sections 15 of the pair of finger sections
12 are each provided with an insertion section 15a penetrating the
opening section 11a of the main body section 11. The other end
sections 15 of the pair of finger sections 12 are arranged to be
movable along the opening section 11a. Specifically, the other end
sections 15 of the pair of finger sections 12 is arranged to be
movable along the circular arc centered on the first rotating shaft
13 viewed from the direction perpendicular to the mounting surface
33a. Further, there is adopted a configuration in which the pair of
finger sections 12 move in the same plane.
[0070] The "finger section" of the pair of finger sections 12 is
composed of one finger or a plurality of fingers. It should be
noted that if the finger section is composed of a plurality of
fingers, the operation of one of the fingers is followed by the
operation of the rest of the fingers. In other words, it is not
achievable that one of the fingers and the rest thereof operate
independently from each other.
[0071] The open/close mechanism (rotation mechanism) of the pair of
finger sections 12 has a configuration of rotating the one end
sections 14 of the pair of finger sections 12 around the first
rotating shaft 13 using a drive device such as an electric motor.
The pair of finger sections 12 have a configuration of a
"single-degree-of-freedom system (the system in which the position
of an object can be expressed by a single parameter)" in which the
two finger sections 12 are controlled using the rotational angle of
the rotation of the two finger sections 12 around the first
rotating shaft 13 as the single parameter.
[0072] The pair of finger sections 12 are formed bending so that
the sides opposed to each other each form a concave shape. The pair
of finger sections 12 each have a plurality of (two) gripping
surfaces 12a, 12b intersecting with each other on the side having
contact with the first object W1 on the lateral side thereof. The
pair of finger sections are arranged to have contact with the first
object W1 at four or more contact points in the gripping surfaces
12a, 12b for gripping the first object W1 from the lateral side
thereof. By thus increasing the contact points, it becomes easy to
grip the first object W1 stably at a predetermined position. The
pair of finger sections 12 can be formed by, for example, cutting
metal (rectangular solid) such as aluminum. The control device 60
performs the control so as to make the pair of finger sections 12
grip the first object W1 at four or more contact points.
[0073] In both of the pair of finger sections 12, the gripping
surfaces 12a, 12b (see FIG. 2A) are perpendicular to the surface
(the upper surface of the first conveyer belt 33) 33a on which the
first object W1 is mounted. It should be noted that in the
explanation below, the surface (the upper surface of the first
conveyer belt 33) on which the first object W1 is mounted is
referred to simply as a "mounting surface" in some cases.
[0074] Incidentally, if the object is, for example, small-sized and
lightweight, it becomes difficult to accurately detect the position
and the posture of the object using a camera, and accurate
positioning of the gripping section for gripping the object is not
achievable in some cases. If the accurate positioning of the
gripping section is not achievable, the object and the gripping
section might have contact with each other at an unintended place
during the gripping operation. On that occasion, since the object
is lightweight, the object moves in an unintended direction, and
there arises a problem that it is not achievable to hold the object
at a desired position or a problem that the object flies out of the
gripping space.
[0075] FIG. 17 is a diagram showing the relationship (the
relationship between the frictional force and the push-out force
for realizing the self-alignment) between the forces generated when
gripping an object WX with a gripping section 10X. In FIG. 17, an
X-Y coordinate system is set on the surface on which the object WX
is disposed, and the contact point between one side (-X-direction
side) of the gripping section and the object WX is set as an
origin. In FIG. 17, the reference symbol F denotes the force with
which the gripping section 10X pushes out the object WX, the
reference symbol f.sub.s denotes the component of the push-out
force F in the direction of the incline of the gripping section
10X, the reference symbol f.sub.y denotes the X-axis direction
component of the push-out force F, the reference symbol f.sub.f
denotes the frictional force exerted on the object WX from the
gripping section 10x, and the reference symbol .theta. denotes the
angle formed between the incline of the gripping section 10X and
the Y axis. It should be noted that since the mass of the object WX
is small, the frictional force between the object WX and the
surface on which the object WX is disposed is ignored in this
drawing.
[0076] As shown in FIG. 17, by decomposing the force F with which
the gripping section 10X pushes out the object WX into the
component f.sub.s in the direction of the incline of the gripping
section 10X and the X-axis direction component f.sub.y, the
components are expressed as Formulas 1 and 2 below. It should be
noted that the component f.sub.y is canceled out.
f.sub.s=F tan .theta. (1)
f.sub.y=F/cos .theta. (2)
[0077] Further, the frictional force f.sub.f exerted on the object
WX from the gripping section 10X can be expressed as Formula 3
below assuming the frictional coefficient as .mu..
f.sub.f=.mu.F (3)
[0078] Here, the condition for the object WX to be pushed out by
the gripping section 10X is expressed as Formula 4 below.
f.sub.s>f.sub.f (4)
[0079] Therefore, according to Formulas 1, 3, and 4, the condition
for the object WX to be pushed out by the gripping section 10X is
expressed as Formula 5 below.
.mu.<tan .theta. (5)
[0080] According to the above description, it is understood that
when gripping the object WX with the gripping section 10X, by
fulfilling Formula 5, it is possible to push out the object WX with
the gripping section 10X to thereby realize the self-alignment.
[0081] Therefore, the robot 1 according to the present embodiment
of the invention has a configuration including the gripping section
10A having the pair of finger sections 12 and the main body section
11 coupled to the pair of finger sections 12, having the one end
sections 14 of the pair of finger sections 12 connected to each
other rotatably around the first rotating shaft 13 disposed at the
position separate from the main body section 11, having the other
end sections 15 of the pair of finger sections 12 swinging in the
plane parallel to the mounting surface 33a centered on the first
rotating shaft 13 to thereby open and close the pair of finger
sections 12, thus gripping the object (the first object W1), the
moving device (the arm 20A, the first conveyer belt 33) for moving
the first object W1 and the gripping section 10A relatively to each
other, and the control device 60 for controlling the moving device
to move the gripping section 10A relatively toward the first object
W1, and then dispose the pair of finger sections 12 in the
periphery of the first object W1, and controlling the gripping
section 10A to open and close the pair of finger sections 12 in the
plane parallel to the mounting surface 33a on which the first
object W1 is mounted to thereby pinch the first object W1 between
the pair of finger sections 12 from the lateral side of the first
object W1, and then grip the first object W1 with the gripping
section 10A at three or more contact points. Hereinafter, the
operation of the robot 1 according to the present embodiment will
be explained with reference to FIGS. 3A through 3D, and 4.
[0082] FIGS. 3A through 3D are plan views showing the operation of
the gripping section according to the first embodiment. FIG. 4 is a
flowchart showing the operation of the robot 1 according to the
first embodiment. FIG. 3A shows the process of moving the gripping
section 10A relatively toward the first object W1, FIG. 3B shows
the condition of disposing the pair of finger sections 12 in the
periphery of the first object W1, FIG. 3C shows the condition of
pinching the first object W1 between the pair of finger sections 12
from the lateral side of the first object W1, and FIG. 3D shows the
condition of making the gripping section 10A grip the first object
W1. It should be noted that in FIGS. 3A through 3D, the reference
symbols .theta.1a, .theta.1b, .theta.1c, and .theta.1d denote the
angle formed between the pair of finger sections 12 around the
first rotating shaft 13. Further, the reference symbols G1, G2, G3,
and G4 denote the contact points between the pair of finger
sections 12 and the first object W1. Here, the operation of the
gripping section will be explained showing the gripping section 10A
out of the gripping sections 10A, 10B as an example. Since the
gripping section 10B has substantially the same configuration as
that of the gripping section 10A, the detailed explanation thereof
will be omitted.
[0083] Firstly, the first objects W1 are conveyed to the first
conveyer belt 33 using the feeder 36 (see FIG. 1). Subsequently,
the image of the first object W1 is taken using the camera 40A. The
control device 60 detects the position of the first object W1
mounted on the first conveyer belt 33 (the mounting surface 33a)
based on the imaging result of the camera 40A (step S1 shown in
FIG. 4).
[0084] Subsequently, as shown in FIG. 3A, the control device
controls the arm 20A to move the gripping section 10A relatively
toward the first object W1 (step S2 shown in FIG. 4). The angle
formed between the pair of finger sections 12 on this occasion is
assumed as .theta.1a. Subsequently, the control device 60 controls
the gripping section 10A to grip the first object W1 with the
gripping section 10A. Here, the control device 60 makes the
gripping section 10A achieve the three functions, namely caging,
self-alignment, and frictional gripping of the first object W1.
[0085] It should be noted that "caging" denotes the condition in
which the object (e.g., the first object W1) at a certain position
and a posture exists in a space enclosed by the gripping section
10A and the plane (here, the upper surface 33a of the first
conveyer belt 33) on which the object is disposed. In the caging,
the position and the posture of the first object W1 are not
restricted, but remain free. The term "self-alignment" denotes the
operation of moving the first object W1 to a predetermined position
in the closed space due to the shape of the gripping section 10A
and the frictional force between the gripping section 10A and the
first object W1 when pinching the first object W1 with the gripping
section 10A. The term "frictional gripping" denotes the operation
of making the gripping section 10A hold the first object W1 by
having contact therewith at three or more contact points, and
holding the first object W1 in a direction perpendicular to the
surface 33a on which the first object W1 is disposed using the
frictional force, thereby gripping the first object W1.
[0086] Specifically, as shown in FIG. 3B, the pair of finger
sections 12 is disposed in the periphery of the first object W1,
and then the gripping section 10A is controlled to open and close
the pair of finger sections 12 in the plane parallel to the surface
33a on which the first object W1 is mounted to thereby make (step
S3 shown in FIG. 4) the pair of finger sections 12 surround the
periphery of the first object W1. Thus, the first object W1 is
prevented from jumping out of the area surrounded by the pair of
finger sections 12 (caging). It should be noted that the angle
.theta.1b formed between the pair of finger sections 12 on this
occasion is set smaller than the angle .theta.1a
(.theta.1b<.theta.1a).
[0087] Subsequently, as shown in FIG. 3C, the first object W1 is
pinched between the pair of finger sections 12 from the lateral
side of the first object W1 (step S4 shown in FIG. 4). Thus, the
first object W1 moves with the pair of finger sections 12, and thus
the position thereof is adjusted (self-alignment). It should be
noted that the angle .theta.1c formed between the pair of finger
sections 12 on this occasion is set smaller than the angle
.theta.1b (.theta.1c<.theta.1b).
[0088] Subsequently, as shown in FIG. 3D, the pair of finger
sections 12 are made (step S5 shown in FIG. 4) to grip the first
object W1 at three or more contact points (here, the four contact
points G1, G2, G3, and G4). Thus, the first object W1 is held at a
predetermined position (frictional gripping). On this occasion, the
detection device (see FIG. 1) provided to the gripping section 10A
detects the force of the gripping section 10A for gripping the
first object W1. It should be noted that the angle .theta.1d formed
between the pair of finger sections 12 on this occasion is set
smaller than the angle .theta.1c (.theta.1d<.theta.1c).
[0089] By setting the angle formed between the gripping surfaces
12a, 12b (see FIG. 2A) and the mounting surface 33a to the angle
with which the large contact area with the first object W1 can be
provided, it becomes possible to stably grip the first object W1 in
the "frictional gripping."
[0090] Subsequently, the gripping section 10A conveys the first
object W1 thus gripped to the stage 30 (see FIG. 1).
[0091] According to the robot 1 of the present embodiment, since
the pair of finger sections 12 is opened and closed in a plane
parallel to the mounting surface 33a after moving to the periphery
of the first object W1 due to the control of the control device 60,
it results that the periphery of the first object W1 is surrounded
by the pair of finger sections 12. Thus, the first object W1 is
prevented from jumping out of the area surrounded by the pair of
finger sections 12 (caging). Further, since the pair of finger
sections 12 pinch the first object W1 from the lateral side
thereof, the first object W1 moves with the pair of finger sections
12, and thus the position is adjusted (self-alignment). Further,
since the gripping section 10A grips the object at three or more
contact points (here, the four contact points G1, G2, G3, and G4),
it is possible to restrict the position of the first object W1, and
at the same time, to stably grip the first object W1 due to the
friction at the contact points (frictional gripping). According to
the operation of the gripping section 10A described above, the
first object W1 can be gripped at a predetermined position.
Therefore, it is possible to provide the robot 1 capable of
preventing the first object W1 from escaping, and reliably gripping
the first object W1 at a predetermined position. Further, since the
pair of finger sections 12 are opened and closed in response to the
swing of the other end side of the pair of finger sections 12
taking the one end sections 14 of the pair of finger sections 12 as
the center of the rotation, it becomes easy to grip the object even
in the case, for example, in which the object is disposed in a
small area.
[0092] According to this configuration, the pair of finger sections
12 have contact with the first object W1 at four or more contact
points in the gripping surfaces 12a, 12b for gripping the first
object W1 from the lateral side thereof. By thus increasing the
contact points, it becomes easy to grip the first object W1 stably
at a predetermined position.
[0093] According to this configuration, since the gripping surfaces
12a, 12b are perpendicular to the mounting surface 33a in both of
the pair of finger sections 12, the first object W1 can be
prevented from jumping out vertically when pinching the first
object W1 compared to the case in which the angle formed between
the gripping surfaces and the mounting surface is an acute angle or
an obtuse angle in both of the pair of finger sections. If, for
example, the angle formed between the gripping surfaces and the
mounting surface 33a is an acute angle in both of the pair of
finger sections 12, the first object W1 jumps out downward in some
cases when pinching the first object W1 (see FIG. 3B). In contrast,
if, for example, the angle formed between the gripping surfaces and
the mounting surface 33a is an obtuse angle in both of the pair of
finger sections 12, the first object W1 jumps out upward in some
cases when pinching the first object W1 (see FIG. 3C).
[0094] According to this configuration, since there is provided the
camera 40A for taking the picture of the first object W1, it is
possible to perform accurate positioning of the gripping section
10A for gripping the first object W1.
[0095] According to this configuration, the gripping section 10A is
provided with the detection device 41A for detecting the force used
for gripping the first object W1. Therefore, the gripping force of
the gripping section 10A can be controlled so that no excessive
load is applied to the first object W1. Therefore, it becomes
possible to prevent the first object W1 from being deformed or
damaged when gripping the first object W1.
[0096] It should be noted that although in the present embodiment,
the explanation is presented citing the example of providing two
arms (the arm 20A and the arm 20B) to every robot, the number of
arms is not limited thereto. It is also possible to provide only
one arm to every robot, or to provide three or more arms to every
robot.
[0097] Further, although in the present embodiment, the explanation
is presented citing the case in which the first object has a
roughly columnar shape as an example, the shape is not limited
thereto. It is also possible to use objects having a variety of
shapes such as nuts or screws besides the gears (gear wheels) as
the first object.
Second Embodiment
[0098] FIGS. 5A and 5B are diagrams corresponding respectively to
FIGS. 2A and 2B, and showing a configuration of a gripping section
110 according to a second embodiment of the invention. FIG. 5A is a
plan view showing a configuration of the gripping section 110
according to the second embodiment. FIG. 5B is a cross-sectional
view along the line B-B shown in FIG. 5A. The gripping section 110
of the present embodiment is different from the gripping section
10A explained in the first embodiment described above in the point
that the first object W1 is gripped at three or more contact points
by making the first object W1 have contact with a pair of finger
sections 112 and the main body section 11. In FIGS. 5A and 5B, the
elements substantially the same as those shown in FIGS. 2A and 2B
are denoted with the same reference symbols, and the detailed
explanation therefor will be omitted.
[0099] As shown in FIGS. 5A and 5B, the gripping section 110 is
provided with the main body section 11 and the pair of finger
sections 112. The gripping section 110 is arranged to open and
close the pair of finger sections 112 by swinging the other end
side (here, the other end sections 115) of the pair of finger
sections 112 in a plane parallel to the mounting surface 33a
centered on a first rotating shaft 113.
[0100] The other end sections 115 of the pair of finger sections
112 are each provided with an insertion section 115a penetrating
the opening section 11a of the main body section 11. The other end
sections 115 of the pair of finger sections 112 are arranged to be
movable along the opening section 11a. Specifically, the other end
sections 115 of the pair of finger sections 112 is arranged to be
movable along the circular arc centered on the first rotating shaft
113 viewed from the direction perpendicular to the mounting surface
33a. Further, there is adopted a configuration in which the pair of
finger sections 112 move in the same plane.
[0101] The pair of finger sections 112 each have a flat gripping
surface 112a on the side having contact with the first object W1 on
the lateral side thereof. In both of the pair of finger sections
112, the gripping surfaces 112a are perpendicular to the mounting
surface 33a. The control device 60 (see FIG. 1) controls the pair
of finger sections 112 and the main body section 11 to grip the
first object W1 at three or more contact points. Hereinafter, the
operation of the gripping section 110 according to the present
embodiment will be explained with reference to FIGS. 4, and 6A
through 6D.
[0102] FIGS. 6A through 6D are plan views corresponding
respectively to FIGS. 3A through 3D, and showing the operation of
the gripping section 110 according to the second embodiment. FIG.
6A shows the process of moving the gripping section 110 relatively
toward the first object W1, FIG. 6B shows the condition of
disposing the pair of finger sections 112 in the periphery of the
first object W1, FIG. 6C shows the condition of pinching the first
object W1 between the pair of finger sections 112 from the lateral
side of the first object W1, and FIG. 6D shows the condition of
making the gripping section 110 grip the first object W1. It should
be noted that in FIGS. 6A through 6D, the reference symbols
.theta.2a, .theta.2b, .theta.2c, and .theta.2d denote the angle
formed between the pair of finger sections 112 around the first
rotating shaft 113. Further, the reference symbols G11, G12, and
G13 denote the contact points between the gripping section 110 and
the first object W1.
[0103] Regarding the step S1 shown in FIG. 4, since the operation
is substantially the same as the operation of the gripping section
10A according to the first embodiment, the detailed explanation
therefor will be omitted.
[0104] As shown in FIG. 6A, the control device 60 controls the arm
20A (see FIG. 1) to move the gripping section 110 relatively toward
the first object W1 (step S2 shown in FIG. 4). The angle formed
between the pair of finger sections 112 on this occasion is assumed
as .theta.2a. Subsequently, the control device 60 controls the
gripping section 110 to grip the first object W1 with the gripping
section 110. Here, the control device 60 makes the gripping section
110 achieve the three functions, namely caging, self-alignment, and
frictional gripping of the first object W1.
[0105] Specifically, as shown in FIG. 6B, the pair of finger
sections 112 is disposed in the periphery of the first object W1,
and then the gripping section 110 is controlled to open and close
the pair of finger sections 112 in the plane parallel to the
mounting surface 33a to thereby make (step S3 shown in FIG. 4) the
pair of finger sections 112 surround the periphery of the first
object W1. Thus, the first object W1 is prevented from jumping out
of the area surrounded by the pair of finger sections 112 (caging).
It should be noted that the angle .theta.2b formed between the pair
of finger section 112 on this occasion is set smaller than the
angle .theta.2a (.theta.2b<.theta.2a).
[0106] Subsequently, as shown in FIG. 6C, the first object W1 is
pinched between the pair of finger sections 112 from the lateral
side of the first object W1 (step S4 shown in FIG. 4). Thus, the
first object W1 moves with the pair of finger sections 112, and
thus the position thereof is adjusted (self-alignment). It should
be noted that the angle .theta.2c formed between the pair of finger
section 112 on this occasion is set smaller than the angle
.theta.2b (.theta.2c<.theta.2b).
[0107] Subsequently, as shown in FIG. 6D, the pair of finger
sections 112 and the main body section 11 are made (step S5 shown
in FIG. 4) to grip the first object W1 at three or more contact
points (here, the three contact points G11, G12, and G13). Thus,
the first object W1 is held at a predetermined position (frictional
gripping). It should be noted that the angle .theta.2d formed
between the pair of finger section 112 on this occasion is set
smaller than the angle .theta.2c (.theta.2d<.theta.2c).
Third Embodiment
[0108] FIGS. 7A and 7B are diagrams showing a configuration of a
gripping section 210 according to the third embodiment of the
invention. FIG. 7A is a plan view corresponding to FIG. 2A, and
showing a configuration of the gripping section 210 according to
the third embodiment of the invention. FIG. 7B is a cross-sectional
view showing a configuration of the gripping section 210 according
to the third embodiment of the invention. The gripping section 210
of the present embodiment is different from the gripping section
10A explained in the first embodiment described above in the point
that a guard 212c for preventing the first object W1 from jumping
out in a direction perpendicular to the mounting surface 33a is
disposed on the opposite side of each of the pair of finger
sections 212 to the mounting surface 33a across the first object
W1. In FIGS. 7A and 7B, the elements substantially the same as
those shown in FIGS. 2A and 2B are denoted with the same reference
symbols, and the detailed explanation therefor will be omitted.
[0109] As shown in FIGS. 7A and 7B, the gripping section 210 is
provided with the main body section 11 and the pair of finger
sections 212. The gripping section 210 is arranged to open and
close the pair of finger sections 212 by swinging the other end
side (here, the other end sections 215) of the pair of finger
sections 212 in a plane parallel to the mounting surface 33a
centered on the first rotating shaft 213.
[0110] The pair of finger sections 212 each have a plurality of
(two) gripping surfaces 212a, 212b intersecting with each other on
the side having contact with the first object W1 on the lateral
side thereof. In both of the pair of finger sections 212, the
gripping surfaces 212a, 212b are perpendicular to the mounting
surface 33a. The control device 60 (see FIG. 1) controls the pair
of finger sections 212 to grip the first object W1 at four or more
contact points.
[0111] The guard 212c for preventing the first object W1 from
jumping out in a direction perpendicular to the mounting surface
33a is disposed on the opposite side of each of the pair of finger
sections 212 to the mounting surface 33a across the first object
W1. The lower surface of the guard 212c is arranged to be parallel
to the mounting surface 33a.
[0112] FIGS. 8A and 8B are diagrams showing a condition of the
gripping section 210 according to the third embodiment of the
invention gripping the object. FIG. 8A is a plan view corresponding
to FIG. 7A, and showing the condition of the gripping section 210
according to the third embodiment of the invention gripping the
object. FIG. 8B is a cross-sectional view corresponding to FIG. 7B,
and showing the condition of the gripping section 210 according to
the third embodiment of the invention gripping the object. It
should be noted that in FIGS. 8A and 8B the reference symbols G21,
G22, G23, and G24 denote the contact points between the gripping
section 210 and the first object W1.
[0113] As shown in FIG. 8A, the pair of finger sections 212 are
controlled (step S5 shown in FIG. 4) to grip the first object W1 at
four or more contact points (here, the four contact points G21,
G22, G23, and G24). Thus, the first object W1 is held at a
predetermined position.
[0114] As shown in FIG. 8B, the bottom surface (-Z-direction side)
of the first object W1 has contact with the mounting surface 33a,
and the top surface (+Z-direction side) of the first object W1 has
contact with the lower surface of the guard 212c. In such a manner
as described above, the first object W1 is gripped while having
contact with the gripping surfaces 212a, 212b, and the lower
surface of the guard 212c.
[0115] According to the robot of the present embodiment, it is
possible to prevent the first object from jumping out upward when
pinching the first object W1.
[0116] It should be noted that although in the present embodiment,
the explanation is presented citing the configuration of providing
the guards to both of the pair of finger sections as an example,
the configuration is not limited thereto. It is also possible to
adopt the configuration of, for example, providing the guard to
either one of the pair of finger sections. In other words, it is
sufficient for the configuration to provide the guard to at least
one of the pair of finger sections. It should be noted that it is
required for the guard to have the area sufficient to prevent the
first object W1 from jumping out upward.
Fourth Embodiment
[0117] FIGS. 9A and 9B are diagrams showing a configuration of a
gripping section 310 according to a fourth embodiment of the
invention. FIG. 9A is a plan view corresponding to FIG. 7A, and
showing a configuration of the gripping section 310 according to
the fourth embodiment of the invention. FIG. 9B is a side view
showing the configuration of the gripping section 310 according to
the fourth embodiment of the invention. The gripping section 310 of
the present embodiment is different from the gripping section 210
explained in the third embodiment described above in the point that
a pair of finger sections 320 are each provided with a tip section
321 disposed in parallel to the mounting surface 33a and gripping
the first object W1, and a base end section 322 disposed in a
direction getting apart from the mounting surface 33a and coupled
to the main body section 11. In FIGS. 9A and 9B, the elements
substantially the same as those shown in FIGS. 7A and 7B are
denoted with the same reference symbols, and the detailed
explanation therefor will be omitted.
[0118] As shown in FIGS. 9A and 9B, the gripping section 310 is
provided with the main body section 11 and the pair of finger
sections 320. The gripping section 310 is arranged to open and
close the pair of finger sections 320 by swinging the other end
side (here, base end sections 322) of the pair of finger sections
320 in a plane parallel to the mounting surface 33a centered on a
first rotating shaft 313.
[0119] The pair of finger sections 320 are each provided with the
tip section 321 disposed in parallel to the mounting surface 33a
and gripping the first object W1, and the base end section 322
disposed in the direction getting apart from the mounting surface
33a and coupled to the main body section 11.
[0120] The tip section 321 of each of the pair of finger sections
320 has a plurality of gripping surfaces (here, the two surfaces)
321a, 321b intersecting with each other on the side having contact
with the first object W1 on the lateral side thereof. In both of
the pair of finger sections 320, the gripping surfaces 321a, 321b
are perpendicular to the mounting surface 33a. The control device
60 (see FIG. 1) performs the control so as to make the tip sections
321 of the pair of finger sections 320 grip the first object W1 at
four or more contact points.
[0121] A guard 321c for preventing the first object W1 from jumping
out in a direction perpendicular to the mounting surface 33a is
disposed on the opposite side of the tip section 321 of each of the
pair of finger sections 320 to the mounting surface 33a across the
first object W1.
[0122] A surface 321d of the tip section 321 of each of the pair of
finger sections 320 opposed to the mounting surface 33a is a flat
plane.
[0123] In the pair of finger sections 320, the tip section 321 and
the base end section 322 are arranged so as not to overlap each
other viewed from the direction (here, the Z-axis direction) in
which the image of the tip section 321 is taken by a camera 340. It
should be noted that the camera 340 is disposed at the position
overlapping the first object W1 viewed from the direction
perpendicular to the mounting surface 33a.
[0124] In the pair of finger sections 320, the angle .theta.1
formed between the tip section 321 and the base end section 322 is
an obtuse angle.
[0125] According to the robot of the present embodiment, it becomes
easy to grip the first object W1 at a predetermined position
compared to the configuration in which whole of the pair of finger
sections is disposed in parallel to the mounting surface. In the
case of gripping the first object mounted on the mounting surface,
by making the pair of finger sections perform the gripping
operation while making the pair of finger sections have contact
with the mounting surface, it becomes easy to stably grip the first
object. If there is adopted the configuration, for example, in
which the tip section and the base end section are arranged in
parallel to each other in the pair of finger sections, the main
body section and the mounting surface have contact with each other
when gripping the first object, and the tip section and the
mounting surface become distant from each other to thereby make it
difficult to grip the first object. However, according to the
configuration of the present embodiment of the invention, it
becomes easy to make the tip sections 321 of the pair of finger
sections 320 have contact with the mounting surface 33a. Therefore,
it becomes easy to grip the first object W1 at a predetermined
position.
[0126] According to this configuration, it becomes easy to make the
tip sections 321 of the pair of finger sections 320 have contact
with the mounting surface 33a compared to the configuration in
which the surface of the tip section of each of the pair of finger
sections opposed to the mounting surface is an uneven surface.
Therefore, it becomes easy to grip the first object W1 at a
predetermined position.
[0127] According to this configuration, it is possible to perform
the gripping operation while checking the gripping operation of the
tip sections 321.
[0128] According to this configuration, it becomes easy to perform
the gripping operation while checking the gripping operation of the
tip sections 321 compared to the configuration in which the angle
formed between the tip section and the base end section is an acute
angle. If there is adopted a configuration, for example, in which
the angle formed between the tip section and the base end section
is an acute angle, there is a possibility that the tip section is
shaded by the base end section when viewed from the direction in
which the image of the tip section is taken by the camera, and it
becomes difficult to detect the accurate gripping operation of the
tip sections. However, according to the configuration of the
present embodiment of the invention, the tip sections 321 are
hardly shaded by the base end sections 322 viewed from the
direction in which the image of the tip sections 321 is taken by
the camera 340. Therefore, it becomes easy to perform the gripping
operation while checking the gripping operation of the tip sections
321.
Fifth Embodiment
[0129] FIGS. 10A and 10B are plan views corresponding to FIG. 2A
and showing a configuration of a gripping section 410 according to
a fifth embodiment of the invention. FIG. 10A is a plan view
corresponding to the condition of moving the gripping section 410
relatively toward the first object W1, or the condition of
disposing a pair of finger sections 420 in the periphery of the
first object W1. FIG. 10B is a plan view corresponding to the
condition of pinching the first object W1 between the pair of
finger sections 420 from the lateral side of the first object W1,
or the condition of making the gripping section 410 grip the first
object W1. In FIGS. 10A and 10B, the reference symbols .theta.3a1,
.theta.3b1 denote the angle (the angle formed between the pair of
finger sections 420 around a first rotating shaft 423) formed
between first link sections 421 of the pair of finger sections 420,
the reference symbols .theta.3a2, .theta.3b2 denote the angle (the
angle formed by each of the pair of finger sections 420 around a
third rotating shaft 422) formed between the first link section 421
and a second link section 431 of each of the pair of finger
sections 420. The gripping section 410 of the present embodiment is
different from the gripping section 10A explained in the first
embodiment described above in the point that each of the pair of
finger sections 420 is provided with the first link section 421
rotatably coupled to the first rotating shaft 423 at one end, and
the second link section 431 rotatably coupled to a second rotating
shaft 412 provided to a main body section 411 at one end, and
rotatably coupled to the other end of the first link section 421 at
the other end. In FIGS. 10A and 10B, the elements substantially the
same as those shown in FIG. 2A are denoted with the same reference
symbols, and the detailed explanation therefor will be omitted.
[0130] As shown in FIGS. 10A and 10B, the gripping section 410 is
provided with the main body section 411 and the pair of finger
sections 420. The pair of finger sections 420 are each provided
with the first link section 421 and the second link section 431.
The gripping section 410 is arranged to open and close the pair of
finger sections 420 by swinging the other end side (here, the other
end sections 425 of the first link sections 421) of the pair of
finger sections 420 in a plane parallel to the mounting surface 33a
centered on the first rotating shaft 423.
[0131] The open/close mechanism (the rotation mechanism) of the
pair of finger sections 420 has, for example, a configuration of
providing a linear groove (through hole) to the main body section
411, providing the second rotating shaft 412 to the groove, and
making the second rotating shaft 412 penetrate the second link
sections 431 of the pair of finger sections 420, thereby moving the
pair of finger sections 420 along the linear groove by a drive
device such as an electric motor. Further, the open/close mechanism
has a configuration of disposing the second link sections 431 of
the pair of finger sections 420 rotatably to the second rotating
shaft 412 to thereby rotate the second link sections 431 of the
pair of finger sections 420 around the second rotating shaft 412 by
a drive device such as an electric motor. According to the
configuration, the other end sections 425 of the first link
sections 421 in the pair of finger sections 420 are swung in a
plane parallel to the mounting surface 33a centered on the first
rotating shaft 423 with the rotation of the second link sections
431 in the pair of finger sections 420 around the second rotating
shaft 412.
[0132] The first link section 421 of each of the pair of finger
sections 420 has a flat gripping surface 421a on the side having
contact with the first object W1 on the lateral side thereof. In
both of the pair of finger sections 420, the gripping surfaces 421a
are perpendicular to the mounting surface 33a. The second link
section 431 of each of the pair of finger sections 420 has a flat
gripping surface 431a on the side having contact with the first
object W1 on the lateral side thereof. In both of the pair of
finger sections 420, the gripping surfaces 431a are perpendicular
to the mounting surface 33a. The control device 60 (see FIG. 1)
controls the pair of finger sections 420 to grip the first object
W1 at four or more contact points.
[0133] As shown in FIG. 10A, the angle formed between the pair of
finger sections 420 around the first rotating shaft 423 on this
occasion (in the case of moving the gripping section 410 relatively
toward the first object W1, or the case of disposing the pair of
finger sections 420 in the periphery of the first object W1) is
denoted with .theta.3a1, and the angle formed by each of the pair
of finger sections 420 around the third rotating shaft 422 on this
occasion is denoted with .theta.3a2.
[0134] As shown in FIG. 10B, the angle .theta.3b1 formed between
the pair of finger sections 420 around the first rotating shaft 423
on this occasion (in the case of pinching the first object W1
between the pair of finger sections 420 from the lateral side of
the first object W1) becomes smaller than the angle .theta.3a1
(.theta.3b1<.theta.3a1). In contrast, the angle .theta.3b2
formed by each of the pair of finger sections 420 around the third
rotating shaft 422 becomes larger than the angle .theta.3a2
(.theta.3b2>.theta.3a2).
[0135] The position of the second rotating shaft 412 moves along
the straight line connecting the first rotating shaft 423 and the
second rotating shaft 412 in a direction opposite to the direction
toward the first rotating shaft 423 as the pair of finger sections
420 move in the closing direction. It is arranged that the position
(the distance between the main body section 411 and the first
rotating shaft 423) of the first rotating shaft 423 is fixed in
place in such a manner as described above.
[0136] By thus increasing the link sections 421, 431, it becomes
easy to grip the first object W1 stably at a predetermined
position.
[0137] According to this configuration, it is possible to arrange
that the first object hardly moves with the closing operation of
the pair of finger sections 420. Therefore, it becomes easy to
stably grip the first object W1 at a predetermined position.
First Modified Example
[0138] FIGS. 11A and 11B are diagrams corresponding respectively to
FIGS. 5A and 5B, and showing a first modified example of the
gripping section according to the invention. FIG. 11A is a plan
view showing the first modified example of the gripping section
according to the invention. FIG. 11B is a cross-sectional view
along the line C-C shown in FIG. 11A. A gripping section 501 of the
present modified example is different from the gripping section 110
explained in the second embodiment described above in the point
that a main body section 511 is provided with a projection 511a,
and the other end section 515 of each of a pair of finger sections
512 is provided with a groove 515a. In FIGS. 11A and 11B, the
elements substantially the same as those shown in FIGS. 5A and 5B
are denoted with the same reference symbols, and the detailed
explanation therefor will be omitted.
[0139] As shown in FIGS. 11A and 11B, the gripping section 501 is
provided with the main body section 511 and the pair of finger
sections 512. The gripping section 501 is arranged to open and
close the pair of finger sections 512 by swinging the other end
side (here, the other end sections 515) of the pair of finger
sections 512 in a plane parallel to the mounting surface 33a
centered on a first rotating shaft 513.
[0140] The other end section 515 of each of the pair of finger
sections 512 is provided with the groove 515a having a roughly T
cross-sectional shape on the side having contact with the main body
section 511. The main body section 511 is formed so that the side
(the +Y-direction side) on which the pair of finger sections 512
are disposed is curved. The main body section 511 is provided with
the projection 511a having a circular arc planar shape along the
curved portion, and a roughly T cross-sectional shape. The other
end sections 515 of the pair of finger sections 512 are arranged to
be movable along the projection 511a. Specifically, the other end
section 515 of each of the pair of finger sections 512 is arranged
to be movable along the circular arc centered on the first rotating
shaft 513 viewed from a direction perpendicular to the mounting
surface 33a.
[0141] The pair of finger sections 512 each have a flat gripping
surface 512a on the side having contact with the first object W1 on
the lateral side thereof. In both of the pair of finger sections
512, the gripping surfaces 512a are perpendicular to the mounting
surface 33a. The control device 60 (see FIG. 1) controls the pair
of finger sections 512 and the main body section 511 to grip the
first object W1 at three or more contact points.
Second Modified Example
[0142] FIGS. 12A through 12D are diagrams corresponding to FIGS. 5A
and 5B, and showing a second modified example of the gripping
section according to the invention. FIG. 12A is a plan view showing
the second modified example of the gripping section according to
the invention. FIG. 12B is a cross-sectional view along the line
D1-D1 shown in FIG. 12A. FIG. 12C is a cross-sectional view along
the line D2-D2 shown in FIG. 12A. FIG. 12D is a side view showing a
part of the pair of finger sections, which has contact with the
object to thereby grip the object. A gripping section 502 according
to the present modified example is different from the gripping
section 110 explained in the second embodiment described above in
the point that a main body section 521 is provided with projections
521a, 521b, the other end section 525A of one finger section 522A
out of a pair of finger sections 522A, 522B is provided with a
groove 525Ab, and the other end section 525B of the other finger
section 522B is provided with a groove 525Bb. In FIGS. 12A through
12D, the elements substantially the same as those shown in FIGS. 5A
and 5B are denoted with the same reference symbols, and the
detailed explanation therefor will be omitted.
[0143] As shown in FIGS. 12A through 12D, the gripping section 502
is provided with the main body section 521 and the pair of finger
sections 522A, 522B. The gripping section 502 is arranged to open
and close the pair of finger sections 522A, 522B by swinging the
other end side (here, the other end sections 525A, 525B) of the
pair of finger sections 522A, 522B in a plane parallel to the
mounting surface 33a centered on the first rotating shaft 523.
[0144] As shown in FIG. 12B, the other end section 525A of the one
finger section 522A out of the pair of finger sections 522A, 522B
is provided with the groove 525Ab having a roughly T
cross-sectional shape in the side having contact with the main body
section 521. The main body section 521 is formed so that the side
(the +Y-direction side) on which the pair of finger sections 522A,
522B are disposed is curved. The side of the main body section 521
having contact with the other end section 525A is provided with the
projection 521a having a circular arc planar shape along the curved
portion, and a roughly T cross-sectional shape. The other end
section 525A of the finger section 522A is arranged to be movable
along the projection 521a. Specifically, the other end section 525A
of the finger section 522A is arranged to be movable along the
circular arc centered on the first rotating shaft 523 viewed from a
direction perpendicular to the mounting surface 33a.
[0145] As shown in FIG. 12C, the other end section 525B of the
other finger section 522B out of the pair of finger sections 522A,
522B is provided with the groove 525Bb having a roughly T
cross-sectional shape in the side having contact with the main body
section 521. The main body section 521 is formed so that the side
(the +Y-direction side) on which the pair of finger sections 522A,
522B are disposed is curved. The side of the main body section 521
having contact with the other end section 525B is provided with the
projection 521b having a circular arc planar shape along the curved
portion, and a roughly T cross-sectional shape. The other end
section 525B of the finger section 522B is arranged to be movable
along the projection 521b. Specifically, the other end section 525B
of the finger section 522B is arranged to be movable along the
circular arc centered on the first rotating shaft 523 viewed from a
direction perpendicular to the mounting surface 33a.
[0146] As shown in FIG. 12D, the height (the distance from the
mounting surface 33a to the upper surface of the gripping part) of
the part, with which the finger section 522A out of the pair of
finger sections 522A, 522B has contact with the first object W1 to
thereby grip the first object W1, from the mounting surface 33a is
denoted with H1, and the height (the distance from the mounting
surface 33a to the upper surface of the gripping part) of the part,
with which the finger section 522B has contact with the first
object W1 to thereby grip the first object W1, from the mounting
surface 33a is denoted with H2. The heights H1, H2 of the parts of
the pair of finger sections 522A, 522B, having contact with and
gripping the first object W1 are equal to each other. It should be
noted that in FIG. 12D, the heights H1, H2 are made different from
each other in order for making the parts of the pair of finger
sections 522A, 522B having contact with and gripping the first
object W1 eye-friendly for the sake of convenience.
[0147] The one finger section 522A out of the pair of finger
sections 522A, 522B has a flat gripping surface 522Aa on the side
having contact with the first object W1 on the lateral side
thereof. The gripping surface 522Aa is perpendicular to the
mounting surface 33a. The other finger section 522B out of the pair
of finger sections 522A, 522B has a flat gripping surface 522Ba on
the side having contact with the first object W1 on the lateral
side thereof. The gripping surface 522Ba is perpendicular to the
mounting surface 33a. The control device 60 (see FIG. 1) controls
the pair of finger sections 522A, 522B and the main body section
521 to grip the first object W1 at three or more contact
points.
[0148] According to the robot of the present modified example,
since the other end section 525A of the one finger section 522A and
the other end section 525B of the other finger section 522B are
disposed on the respective sides opposite to each other across the
main body section 521 in the pair of finger sections 522A, 522B,
there is no chance for the other end section 525A and the other end
section 525B to have contact with each other. In other words, the
other end section 525A, one of the other end sections, and the
other end section 525B, the other of the other end sections, move
in the respective plane different from each other. Therefore, the
freedom of the open/close operation of the pair of finger sections
522A, 522B for gripping the first object W1 can be increased.
[0149] According to this configuration, it becomes easy to stably
grip the first object W1 at a predetermined position when pinching
the first object W1 compared to the case in which the height of the
part having contact with and gripping the first object from the
mounting surface is different between the pair of finger sections.
If, for example, the height of the part having contact with and
gripping the first object from the mounting surface is different
between the pair of finger sections, the first object is tilted to
have an oblique posture or even falls down when pinching the first
object.
Third Modified Example
[0150] FIG. 13 is a plan view corresponding to FIG. 5A, and showing
a third modified example of the gripping section according to the
invention. A gripping section 601 of the present modified example
is different from the gripping section 110 explained in the second
embodiment described above in the point that there is adopted a
configuration in which one end section 614A of one finger section
612A out of a pair of finger sections 612A, 612B rotates around a
first rotating shaft 613A, and one end section 614B of the other
finger section 612B rotates around a first rotating shaft 613B. In
FIG. 13, the elements substantially the same as those shown in FIG.
5A are denoted with the same reference symbols, and the detailed
explanation therefor will be omitted. It should be noted that the
main body section is omitted from the illustration in the drawing
for the sake of convenience.
[0151] As shown in FIG. 13, the gripping section 601 is provided
with the main body section (not shown) and the pair of finger
sections 612A, 612B. The gripping section 601 is arranged to open
and close the pair of finger sections 612A, 612B by swinging the
other end side (here, the other end section 615A) of the one finger
section 612A out of the pair of finger sections 612A, 612B in a
plane parallel to the mounting surface 33a centered on the first
rotating shaft 613A, and at the same time, swinging the other end
side (here, the other end section 615B) of the other finger section
612B in a plane parallel to the mounting surface 33a centered on
the first rotating shaft 613B.
[0152] The other end section 615A of the one finger section 612A
out of the pair of finger sections 612A, 612B is arranged to be
movable along the circular arc centered on the first rotating shaft
613A viewed from the direction perpendicular to the mounting
surface 33a. The other end section 615B of the other finger section
612B is arranged to be movable along the circular arc centered on
the first rotating shaft 613B viewed from the direction
perpendicular to the mounting surface 33a.
[0153] The one finger section 612A out of the pair of finger
sections 612A, 612B has a flat gripping surface 612Aa on the side
having contact with the first object W1 on the lateral side
thereof. The gripping surface 612Aa is perpendicular to the
mounting surface 33a. The other finger section 612B has a flat
gripping surface 612Ba on the side having contact with the first
object W1 on the lateral side thereof. The gripping surface 612Ba
is perpendicular to the mounting surface 33a. The control device 60
(see FIG. 1) controls the pair of finger sections 612A, 612B and
the main body section (not shown) to grip the first object W1 at
three or more contact points.
Fourth Modified Example
[0154] FIG. 14 is a plan view corresponding to FIG. 5A, and showing
a fourth modified example of the gripping section according to the
invention. A gripping section 602 of the present modified example
is different from the gripping section 110 explained in the second
embodiment described above in the point that a pair of finger
sections 622A, 622B have respective curved surfaces 622Aa, 622Ba on
the side having contact with the first object W1 on the lateral
side thereof. In FIG. 14, the elements substantially the same as
those shown in FIG. 5A are denoted with the same reference symbols,
and the detailed explanation therefor will be omitted. It should be
noted that a main body section is omitted from the illustration in
the drawing for the sake of convenience.
[0155] As shown in FIG. 14, the gripping section 602 is provided
with the main body section (not shown) and the pair of finger
sections 622A, 622B. The gripping section 602 is arranged to open
and close the pair of finger sections 622A, 622B by swinging the
other end side (here, the other end section 625A) of the one finger
section 622A out of the pair of finger sections 622A, 622B in a
plane parallel to the mounting surface 33a centered on a first
rotating shaft 623A, and at the same time, swinging the other end
side (here, the other end section 625B) of the other finger section
622B in a plane parallel to the mounting surface 33a centered on a
first rotating shaft 623B.
[0156] The other end section 625A of the one finger section 622A
out of the pair of finger sections 622A, 622B is arranged to be
movable along the circular arc centered on the first rotating shaft
623A viewed from the direction perpendicular to the mounting
surface 33a. The other end section 625B of the other finger section
622B is arranged to be movable along the circular arc centered on
the first rotating shaft 623B viewed from the direction
perpendicular to the mounting surface 33a.
[0157] The one finger section 622A out of the pair of finger
sections 622A, 622B has a curved gripping surface 622Aa concave
toward the side having contact with the first object W1 on the
lateral side thereof. The gripping surface 622Aa is perpendicular
to the mounting surface 33a. The other finger section 622B has a
curved gripping surface 622Ba concave toward the side having
contact with the first object W1 on the lateral side thereof. The
gripping surface 622Ba is perpendicular to the mounting surface
33a. The control device 60 (see FIG. 1) controls the pair of finger
sections 622A, 622B and the main body section (not shown) to grip
the first object W1 at three or more contact points.
Fifth Modified Example
[0158] FIGS. 15A and 15B are diagrams showing a fifth modified
example of the gripping section according to the invention. FIG.
15A is a plan view corresponding to FIG. 5A, and showing the fifth
modified example of the gripping section according to the
invention. FIG. 15B is a side view showing the fifth modified
example of the gripping section according to the invention. A
gripping section 603 according to the present modified example is
different from the gripping section 110 explained in the second
embodiment described above in the point that one finger section
632A out of a pair of finger sections 632A, 632B is composed of a
plurality of fingers (here, two fingers), and the other finger
section 632B is formed of one finger. In FIGS. 15A and 15B, the
elements substantially the same as those shown in FIGS. 5A and 5B
are denoted with the same reference symbols and the detailed
explanation therefor will be omitted. It should be noted that a
main body section is omitted from the illustration in the drawing
for the sake of convenience.
[0159] As shown in FIGS. 15A and 15B, the gripping section 603 is
provided with the main body section (not shown) and the pair of
finger sections 632A, 632B. The gripping section 603 is arranged to
open and close the pair of finger sections 632A, 632B by swinging
the other end side (here, the other end section 635A) of the one
finger section 632A out of the pair of finger sections 632A, 632B
in a plane parallel to the mounting surface 33a centered on a first
rotating shaft 633A, and at the same time, swinging the other end
side (here, the other end section 635B) of the other finger section
632B in a plane parallel to the mounting surface 33a centered on a
first rotating shaft 633B.
[0160] The other end section 635A of the one finger section 632A
out of the pair of finger sections 632A, 632B is arranged to be
movable along the circular arc centered on the first rotating shaft
633A viewed from the direction perpendicular to the mounting
surface 33a. The other end section 635B of the other finger section
632B is arranged to be movable along the circular arc centered on
the first rotating shaft 633B viewed from the direction
perpendicular to the mounting surface 33a.
[0161] The one finger section 632A out of the pair of finger
sections 632A, 632B has a curved gripping surface 632Aa concave
toward the side having contact with the first object W1 on the
lateral side thereof. The gripping surface 632Aa is perpendicular
to the mounting surface 33a. The other finger section 632B has a
curved gripping surface 632Ba concave toward the side having
contact with the first object W1 on the lateral side thereof. The
gripping surface 632Ba is perpendicular to the mounting surface
33a.
[0162] As shown in FIG. 15B, the one finger section 632A out of the
pair of finger sections 632A, 632B is composed of a plurality of
fingers (here, two fingers). The other finger section 632B is
formed of one finger. The control device 60 (see FIG. 1) controls
the pair of finger sections 632A, 632B and the main body section
(not shown) to grip the first object W1 at three or more contact
points.
Sixth Modified Example
[0163] FIGS. 16A through 16C are side views corresponding to FIG.
9B, and showing sixth through eighth modified examples of the
gripping section according to the invention. FIG. 16A is a side
view showing the sixth modified example of the gripping section
according to the invention. It should be noted that, the
configurations described as the sixth through eighth modified
examples can be applied to both of the configuration in which the
pair of finger sections rotate around one rotating shaft and the
configuration in which the pair of finger sections rotate around
two respective rotating shafts different from each other.
[0164] As shown in FIG. 16A, a gripping section 701 of the present
modified example is provided with a main body section 711 and a
pair of finger sections 720. The gripping section 701 is arranged
to open and close the pair of finger sections 720 by swinging the
other end side (here, end portions of base end sections 722) of the
pair of finger sections 720 in a plane parallel to the mounting
surface 33a centered on a first rotating shaft (not shown).
[0165] The pair of finger sections 720 are each provided with one
end section 721 disposed in parallel to the mounting surface 33a
and gripping the first object W1, and a base end section 722
disposed in the direction getting apart from the mounting surface
33a and coupled to the main body section 711.
[0166] In the pair of finger sections 720, the one end section 721
and the base end section 722 are arranged so as not to overlap each
other viewed from the direction in which the image of the one end
section 721 is taken by a camera 740. In the pair of finger
sections 720, the angle .theta.4 formed between the one end section
721 and the base end section 722 is an obtuse angle. The camera 740
is attached to the main body section 711.
[0167] According to the robot of the present modified example,
since the camera 740 is disposed at a position near to the pair of
finger sections 720, it is possible to perform accurate positioning
of the pair of finger sections 720 for gripping the first object
W1.
Seventh Modified Example
[0168] FIG. 16B is a side view showing the seventh modified example
of the gripping section according to the invention. It should be
noted that in FIG. 16B, the first object W1 is omitted from the
illustration for the sake of convenience.
[0169] As shown in FIG. 16B, a gripping section 702 of the present
modified example is provided with the main body section 711 and a
pair of finger sections 720A. The gripping section 702 is arranged
to open and close the pair of finger sections 720A by swinging the
other end side (here, end portions of base end sections 722A) of
the pair of finger sections 720A in a plane parallel to the
mounting surface 33a centered on the first rotating shaft (not
shown).
[0170] The pair of finger sections 720A are each provided with one
end section 721A disposed in parallel to the mounting surface 33a
and gripping the first object W1, and the base end section 722A
disposed in the direction getting apart from the mounting surface
33a and coupled to the main body section 711. A connection section
between the one end section 721A and the base end section 722A has
a curved shape.
[0171] In the pair of finger sections 720A, the one end section
721A and the base end section 722A are arranged so as not to
overlap each other viewed from the direction in which the image of
the one end section 721A is taken by the camera 740. In the pair of
finger sections 720A, the angle .theta.5 formed between the one end
section 721A and the base end section 722A (the angle formed
between the straight portions thereof in a side view) is an obtuse
angle. The camera 740 is attached to the main body section 711.
Eighth Modified Example
[0172] FIG. 16C is a side view showing the eighth modified example
of the gripping section according to the invention. It should be
noted that in FIG. 16C, the first object W1 is omitted from the
illustration for the sake of convenience.
[0173] As shown in FIG. 16C, a gripping section 703 of the present
modified example is provided with the main body section 711 and a
pair of finger sections 720B. The gripping section 703 is arranged
to open and close the pair of finger sections 720B by swinging the
other end side (here, end portions of base end sections 722B) of
the pair of finger sections 720B in a plane parallel to the
mounting surface 33a centered on the first rotating shaft (not
shown).
[0174] The pair of finger sections 720B are each provided with one
end section 721B disposed in parallel to the mounting surface 33a
and gripping the first object W1, and the base end section 722B
disposed in the direction getting apart from the mounting surface
33a and coupled to the main body section 711.
[0175] In the pair of finger sections 720B, the one end section
721B and the base end section 722B are arranged so as not to
overlap each other viewed from the direction in which the image of
the one end section 721B is taken by the camera 740. In the pair of
finger sections 720B, the angle formed between the one end section
721B and the base end section 722B (the angle formed between the
straight portions thereof in a side view) is a right angle. The
camera 740 is attached to the main body section 711.
[0176] It should be noted that although in the embodiments
described above the robot has the configuration of moving the
gripping section using a scalar robot, and making the gripping
section grip the object, the configuration is not limited thereto.
It is also possible to adopt a configuration of, for example,
moving the gripping section using a robot of another type such as a
Cartesian coordinate robot, and making the gripping section grip
the object.
[0177] Further, although in the embodiments described above the
robot has the configuration in which the arms (the moving devices)
are attached on the base, the configuration is not limited thereto.
It is also possible to adopt a configuration in which a bridge
section striding the stage is attached to the base, and the arms
are suspended from the bridge section.
* * * * *