U.S. patent application number 16/160908 was filed with the patent office on 2019-04-18 for tool stocker, interchangeable tool, robot apparatus, robot system, control method of robot system, and storage medium.
The applicant listed for this patent is CANON KABUSHIKI KAISHA. Invention is credited to Hidetada Asano, Naoto Fukuda, Hiroki Kanai, Naonori Kayama, Yoshiyuki Miyazaki, Toshifumi Takahashi.
Application Number | 20190111575 16/160908 |
Document ID | / |
Family ID | 66097257 |
Filed Date | 2019-04-18 |
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United States Patent
Application |
20190111575 |
Kind Code |
A1 |
Asano; Hidetada ; et
al. |
April 18, 2019 |
TOOL STOCKER, INTERCHANGEABLE TOOL, ROBOT APPARATUS, ROBOT SYSTEM,
CONTROL METHOD OF ROBOT SYSTEM, AND STORAGE MEDIUM
Abstract
A tool stocker for holding a tool is equipped with a
stocker-inclining member that inclines the tool stocker and also
equipped with a mechanism that adjusts an attaching/detaching
position at which an interchangeable tool is attached to and
detached from a robot arm. The attaching/detaching position can be
adjusted by using the tool stocker so as to fit moving paths of the
robot arm appropriately.
Inventors: |
Asano; Hidetada;
(Yokohama-shi, JP) ; Kayama; Naonori;
(Yokohama-shi, JP) ; Miyazaki; Yoshiyuki;
(Hiratsuka-shi, JP) ; Takahashi; Toshifumi;
(Utsunomiya-shi, JP) ; Kanai; Hiroki; (Tokyo,
JP) ; Fukuda; Naoto; (Toride-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CANON KABUSHIKI KAISHA |
Tokyo |
|
JP |
|
|
Family ID: |
66097257 |
Appl. No.: |
16/160908 |
Filed: |
October 15, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B25J 15/0066 20130101;
B25J 15/0475 20130101; B25J 15/0491 20130101; B25J 15/0009
20130101 |
International
Class: |
B25J 15/04 20060101
B25J015/04; B25J 15/00 20060101 B25J015/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 18, 2017 |
JP |
2017-202137 |
Oct 19, 2017 |
JP |
2017-202818 |
Nov 30, 2017 |
JP |
2017-230993 |
May 21, 2018 |
JP |
2018-097248 |
Claims
1. A tool stocker that holds an interchangeable tool that can be
attached to and detached from a robot arm and has a contact portion
that performs a predetermined operation on a target object, the
tool stocker comprising: a stocker-inclining member that inclines a
contact surface of the tool stocker to a predetermined angle, the
contact surface coming into contact with the interchangeable tool;
and a position adjustment mechanism that adjusts an
attaching/detaching position at which the interchangeable tool and
the robot arm come into contact with each other.
2. The tool stocker according to claim 1, wherein the robot arm has
a mounting surface with which the interchangeable tool comes into
contact, and wherein the position adjustment mechanism adjusts the
attaching/detaching position in such a manner that the contact
surface and the mounting surface becomes close to or away from each
other when the robot arm engages/disengages the interchangeable
tool.
3. The tool stocker according to claim 1, further comprising a
positioning mechanism that comes into contact with the
interchangeable tool and thereby positions the contact portion to a
predetermined position when the tool stocker holds interchangeable
tool.
4. The tool stocker according to claim 3, wherein when the tool
stocker holds the interchangeable tool, the positioning mechanism
positions the contact portion and the contact portion comes into
contact with the target object and thereby grips the target
object.
5. The tool stocker according to claim 1, further comprising an
electrical connection portion, wherein the interchangeable tool
includes a drive source and the electrical connection portion is
electrically connected to the interchangeable tool to drive the
drive source.
6. The tool stocker according to claim 5, wherein when the
interchangeable tool is detached from the robot arm and held by the
tool stocker, the drive source is driven via the tool stocker and
thereby causes the contact portion to perform part of the
predetermined operation on the target object.
7. The tool stocker according to claim 5, further comprising a
fluid connection portion that supplies air for generating air
pressure to the contact portion that adsorbs and retains the target
object by using the air pressure.
8. An interchangeable tool that is detachably attached to a robot
arm and has contact portions that performs a predetermined
operation on a target object, the interchangeable tool comprising:
a mechanism that moves the contact portions closer to and away from
each other; and a position regulating portion for positioning the
contact portions to a predetermined position in a state in which
the interchangeable tool is detached from the robot arm and held by
the tool stocker.
9. The interchangeable tool according to claim 8, wherein in the
state in which the interchangeable tool is detached from the robot
arm and held by the tool stocker, the position regulating portion
positions the contact portions and the contact portions come into
contact with the target object and grip the target object.
10. The interchangeable tool according to claim 8, further
comprising a first electrical connection portion and a second
electrical connection portion, wherein the position regulating
portion is a drive source that is disposed in the interchangeable
tool and drives the mechanism that moves the contact portions
closer to and away from each other, wherein the first electrical
connection portion is electrically connected to the robot arm to
drive the drive source, and wherein the second electrical
connection portion is electrically connected to the tool stocker to
drive the drive source.
11. The interchangeable tool according to claim 10, wherein when
the interchangeable tool is detached from the robot arm and held by
the tool stocker, the drive source is driven by electric power
supplied from the second electrical connection portion and thereby
the contact portions perform part of the predetermined operation on
the target object.
12. The interchangeable tool according to claim 11, further
comprising: a first fluid connection portion that supplies air for
generating air pressure to the contact portions while the
interchangeable tool is in contact with the robot arm; and a second
fluid connection portion that supplies air for generating the air
pressure to the contact portions while the interchangeable tool is
in contact with the tool stocker, wherein each of the contact
portions adsorbs and retains the target object by using the air
pressure.
13. A robot system comprising: a robot arm having a mounting
surface; an interchangeable tool that can be attached to and
detached from the robot arm and has a contact portion that performs
a predetermined operation on a target object; and a tool stocker
that holds the interchangeable tool, wherein the tool stocker
includes a stocker-inclining member that inclines a contact surface
of the tool stocker to a predetermined angle, the contact surface
coming into contact with the interchangeable tool, and a position
adjustment mechanism that adjusts an attaching/detaching position
at which the interchangeable tool and the robot arm come into
contact with each other, and wherein the tool stocker is disposed
at a position at which the contact surface opposes the mounting
surface of the robot arm on a predetermined moving path of the
robot arm when the interchangeable tool is attached to the robot
arm.
14. The robot system according to claim 13, wherein the
interchangeable tool includes a mechanism that moves the contact
portions closer to and away from each other, and a position
regulating portion for positioning the contact portions to a
predetermined position in a state in which the interchangeable tool
is detached from the robot arm, and wherein the tool stocker
includes a positioning mechanism that comes into contact with the
position regulating portion and thereby positions the contact
portions to a predetermined position when the tool stocker holds
the interchangeable tool.
15. The robot system according to claim 14, further comprising a
supply device that supplies the target object in such a manner that
the interchangeable tool can perform part of a predetermined
operation on the target object in the state in which the
interchangeable tool is held by the tool stocker, wherein when the
tool stocker holds the interchangeable tool, the positioning
mechanism positions the contact portions and the contact portions
come into contact with the target object and thereby grip the
target object.
16. The robot system according to claim 14, wherein the positioning
mechanism includes a lever member that can turn around a turning
axis and an elastic member that elastically urges the lever member,
and wherein the lever member that is elastically urged by the
elastic member presses the position regulating portion and thereby
positions the mechanism that moves the contact portions closer to
and away from each other to a predetermined position.
17. The robot system according to claim 14, wherein the positioning
mechanism is formed of a tapered portion, and wherein the position
regulating portion comes into contact with the tapered portion and
thereby positions the mechanism that moves the contact portions
closer to and away from each other to a predetermined position.
18. The robot system according to claim 14, further comprising a
supply device that supplies the target object in such a manner that
the interchangeable tool can perform part of a predetermined
operation on the target object in the state in which the
interchangeable tool is held by the tool stocker; and a control
device that controls the robot system, wherein the positioning
mechanism is a drive source that is disposed in the interchangeable
tool and drives the mechanism that moves the contact portions
closer to and away from each other, and wherein the control device
causes the supply device to supply the target object, drives the
drive source in the state in which the interchangeable tool is held
by the tool stocker, and causes the contact portions to perform
part of the predetermined operation on the target object.
19. The robot system according to claim 18, wherein the
interchangeable tool includes a first electrical connection portion
that is electrically connected to the robot arm to drive the drive
source, and a second electrical connection portion that is
electrically connected to the tool stocker to drive the drive
source.
20. The robot system according to claim 19, wherein the part of the
predetermined operation is gripping the target object, wherein the
supply device is an adjustment tool that adjusts a gripping
position of the contact portions, and wherein the control device
drives the drive source by using electric power from the second
electrical connection portion and thereby brings the contact
portions into contact with the adjustment tool in a case in which
the interchangeable tool is held by the tool stocker.
21. The robot system according to claim 18, wherein the contact
portion adsorbs and retains the target object by using air
pressure, and wherein the interchangeable tool includes a first
fluid connection portion that supplies air for generating the air
pressure to the contact portion while the interchangeable tool is
in contact with the robot arm, and a second fluid connection
portion that supplies air for generating the air pressure to the
contact portion while the interchangeable tool is in contact with
the tool stocker.
22. A control method of controlling a robot system that includes a
robot arm, an interchangeable tool that can be attached to and
detached from the robot arm and has contact portions that perform a
predetermined operation on a target object, and a tool stocker that
holds the interchangeable tool, the interchangeable tool having a
mechanism that moves the contact portions closer to and away from
each other and a position regulating portion that positions the
mechanism to a predetermined position in a state in which the
interchangeable tool is detached from the robot arm, the tool
stocker having a positioning mechanism that comes into contact with
the position regulating portion and thereby positions the contact
portions to a predetermined position when the tool stocker holds
the interchangeable tool, the control method comprising: holding
the interchangeable tool by using the tool stocker while the
contact portions or the position regulating portion of the
interchangeable tool is brought into contact with the positioning
mechanism of the tool stocker; and positioning the mechanism that
moves the contact portions closer to and away from each other to a
predetermined position by using the positioning mechanism.
23. The control method according to claim 22, wherein the robot
system further includes a supply device that supplies the target
object in such a manner that the interchangeable tool can perform
part of the predetermined operation on the target object in the
state in which the interchangeable tool is held by the tool
stocker, the control method further comprising: supplying the
target object, by using supply device, to a position at which the
interchangeable tool can grip the target object in the state in
which the interchangeable tool is held by the tool stocker, wherein
in the positioning the mechanism, the positioning mechanism
positions the contact portions and the contact portions is brought
into contact with the target object and thereby the interchangeable
tool grips the target object.
24. The control method according to claim 22, wherein the robot
system further includes a supply device that supplies the target
object in such a manner that the interchangeable tool can perform
part of the predetermined operation on the target object in the
state in which the interchangeable tool is held by the tool
stocker, and the positioning mechanism is a drive source that is
disposed in the interchangeable tool and drives the mechanism that
moves the contact portions closer to and away from each other, the
control method further comprising: supplying the target object by
using the supply device in such a manner that the interchangeable
tool can perform part of the predetermined operation on the target
object in the state in which the interchangeable tool is held by
the tool stocker; holding the interchangeable tool by using the
tool stocker; and operating the contact portions to perform part of
the predetermined operation on the target object by driving the
drive source in the state in which the interchangeable tool is held
by the tool stocker.
25. The control method according to claim 24, wherein the supply
device is an adjustment tool that adjusts a gripping position of
the contact portions, the control method further comprising: in
place of the operating the contact portions, bringing the contact
portions and the adjustment tool into contact with each other by
driving the drive source via the tool stocker; recording a contact
position of the contact portions that come into contact with the
adjustment tool in the bringing the contact portions; and
overwriting the gripping position with the contact position
recorded in the recording the contact position.
26. A storage medium that is computer readable, the storage medium
comprising: a control program that is stored therein and that can
implement a control method of controlling a robot system that
includes a robot arm, an interchangeable tool that can be attached
to and detached from the robot arm and has contact portions that
perform a predetermined operation on a target object, and a tool
stocker that holds the interchangeable tool, wherein the
interchangeable tool includes a mechanism that moves the contact
portions closer to and away from each other, and a position
regulating portion that positions the mechanism to a predetermined
position in a state in which the interchangeable tool is detached
from the robot arm, wherein the tool stocker includes a positioning
mechanism that comes into contact with the position regulating
portion and thereby positions the contact portions to a
predetermined position when the tool stocker holds the
interchangeable tool, and wherein the control program includes a
step of holding the interchangeable tool by using the tool stocker
while the contact portions or the position regulating portion of
the interchangeable tool is brought into contact with the
positioning mechanism of the tool stocker, and a step of
positioning the mechanism that moves the contact portions closer to
and away from each other to a predetermined position by using the
positioning mechanism.
Description
BACKGROUND OF THE INVENTION
Field of the Invention
[0001] The present disclosure relates to a tool stocker that holds
an interchangeable tool for performing an operation on a target
object and to a robot system that includes the tool stocker.
Description of the Related Art
[0002] In recent years, automation has been introduced in
assembling and processing works or the like of small industrial
products having complicated structures, such as cameras and
printers. Parts used for such industrial products are often small
precision components and come in a wide range of shapes.
[0003] On the other hand, a single robot apparatus is expected to
manufacture multiple types of products in succession. In production
sites, occasions for setting up the robot apparatus including
replacing tools tend to increase to cope with the change of the
type of workpiece or the work process. Changing the setting of the
robot apparatus manually by an operator requires an effort and
working time. This leads to an increasing demand for a so-called
automated setup in which a software program for the robot apparatus
implements the setup of the robot apparatus as much as
possible.
[0004] In the automated setup, interchangeable tools are stored
mainly in stockers. These stockers are desirably placed in the
vicinity of a target object on which the robot apparatus performs
operations so as to reduce the operating time of the robot
apparatus.
[0005] A robot hand disclosed by Japanese Patent No. 5606423 uses
finger members as a tool for an operation on a target object. The
robot hand is configured to replace the fingers only with other
fingers. The robot hand body is equipped with a finger base that
can attach/detach the fingers. The fingers are attached to the
robot hand in the following manner The fingers are stored in a
finger replacing apparatus that is placed on the floor surface, and
a shaft of the fingers stored in the apparatus is inserted into a
hole portion of the finger base. Subsequently, an
attachment/detachment mechanism built in the finger replacing
apparatus rotates the fingers to fix them to the finger base. The
fingers can be detached by the reverse action.
[0006] According to Japanese Patent No. 5606423, when the fingers
of the robot hand are replaced, a position at which the fingers are
attached/detached is not flexibly changed since the finger
replacing apparatus is made only for storing the finger.
Accordingly, the robot arm must resort to the attaching/detaching
position for replacement. This restricts the moving path of the
robot arm and makes it difficult to generate moving paths of the
robot arm so as to shorten operation time.
[0007] The sets of fingers are stored in one stocker. Thus, every
time a set of fingers are replaced with another, the robot arm
needs to return to the stocker for replacement, which deteriorates
work efficiency.
SUMMARY OF THE INVENTION
[0008] The present disclosure provides a tool stocker that can
provide more freedom in generating moving paths of a robot arm
irrespective of an attaching/detaching position and thereby improve
work efficiency.
[0009] The present disclosure provides a tool stocker that holds an
interchangeable tool that can be attached to and detached from a
robot arm and has a contact portion that performs a predetermined
operation on a target object. The tool stocker includes a
stocker-inclining member that inclines a contact surface of the
tool stocker to a predetermined angle and the contact surface comes
into contact with the interchangeable tool. The tool stocker
further includes a position adjustment mechanism that adjusts an
attaching/detaching position at which the interchangeable tool and
the robot arm come into contact with each other.
[0010] Further features of the present disclosure will become
apparent from the following description of exemplary embodiments
(with reference to the attached drawings).
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a view schematically illustrating a configuration
of a robot system according to a first embodiment.
[0012] FIG. 2 is a block diagram illustrating control of the robot
system according to the first embodiment.
[0013] FIGS. 3A to 3C are views illustrating an
attachment/detachment mechanism for a robot arm body and an
interchangeable tool according to the first embodiment.
[0014] FIG. 4A to 4C are views illustrating a state in which the
interchangeable tool is held by a tool stocker in the first
embodiment.
[0015] FIG. 5 is a side view illustrating a state in which the tool
stockers are arranged in the first embodiment.
[0016] FIG. 6 is a perspective view illustrating a state in which
the tool stockers are arranged in the first embodiment when viewed
from behind the tool stockers.
[0017] FIG. 7 is a cross-sectional view illustrating the tool
stocker and a fixing member according to the first embodiment.
[0018] FIGS. 8A to 8D are views illustrating layout examples of the
tool stockers in the first embodiment.
[0019] FIG. 9 is a view illustrating an attachment/detachment
mechanism for the robot arm body and an interchangeable tool
according to modification example 1 of the first embodiment.
[0020] FIG. 10 is a view illustrating a state in which the
interchangeable tool is held by a tool stocker according to
modification example 1 of the first embodiment.
[0021] FIG. 11 is a cross-sectional view illustrating a state in
which the robot arm body takes the interchangeable tool held by the
tool stocker in modification example 1 of the first embodiment.
[0022] FIGS. 12A to 12C are schematic views illustrating an
interchangeable tool and a tool stocker according to modification
example 2 of the first embodiment.
[0023] FIGS. 13A to 13B are schematic views illustrating the
interchangeable tool and a tool stocker according to modification
example 2 of the first embodiment.
[0024] FIG. 14 is a view schematically illustrating a configuration
of a robot system according to a second embodiment.
[0025] FIG. 15 is a block diagram illustrating control of the robot
system according to the second embodiment.
[0026] FIG. 16 is a detailed view illustrating an interchangeable
tool according to the second embodiment.
[0027] FIG. 17 is a view illustrating a state in which the
interchangeable tool is held by the tool stocker in the second
embodiment.
[0028] FIG. 18 is a view schematically illustrating a
parts-supplying apparatus according to the second embodiment.
[0029] FIG. 19 is a control flowchart for the robot system
according to the second embodiment.
[0030] FIGS. 20A to 20F are views each of which illustrates a state
corresponding to each step in the flowchart in FIG. 19.
[0031] FIG. 21 is a view schematically illustrating a configuration
of a robot system according to a third embodiment.
[0032] FIGS. 22A to 22B are views illustrating an
attachment/detachment mechanism for the robot arm body and an
interchangeable tool according to the third embodiment.
[0033] FIG. 23 is a view illustrating a state in which the
interchangeable tool is attached to the robot arm body in the third
embodiment.
[0034] FIGS. 24A to 24B are views illustrating a state in which the
interchangeable tool is held by the tool stocker in the third
embodiment.
[0035] FIG. 25 is a block diagram illustrating control of the robot
system according to the third embodiment.
[0036] FIG. 26 is a control flowchart of the robot system according
to the third embodiment.
[0037] FIGS. 27A to 27F are views each of which illustrates a state
corresponding to each step in the flowchart in FIG. 26.
[0038] FIGS. 28A to 28B are views illustrating a state in which an
interchangeable tool is held by a tool stocker according to
modification example 1 of the third embodiment.
[0039] FIG. 29 is a view illustrating a state in which an
interchangeable tool is held by the tool stocker in modification
example 2 of the third embodiment.
[0040] FIG. 30 is a control flowchart for the robot system
according to modification example 2 of the third embodiment.
DESCRIPTION OF THE EMBODIMENTS
[0041] Embodiments of the present disclosure will be described with
reference to examples illustrated in the accompanying drawings.
Note that the embodiments described below are examples and one
skilled in the art can arbitrarily modify and alter minor
configurations to the extent not departing from the scope of the
invention.
First Embodiment
[0042] FIG. 1 is a view schematically illustrating a configuration
example of a robot system that can implement the present
disclosure. As illustrated in FIG. 1, a robot system 10 includes a
robot apparatus 20, a tool stocker 500, a pneumatic apparatus 400,
a control device 600, and an external input device 700. The
pneumatic apparatus 400, the control device 600, and the external
input device 700 are shown in the block diagram at the bottom of
FIG. 1.
[0043] The robot apparatus 20 in FIG. 1 is constituted by a robot
arm body 100 and an interchangeable tool 300a that is detachably
attached to the end of the robot arm body 100. In place of the
interchangeable tool 300a, an interchangeable tool 300b can be also
attached to the robot arm body 100. Multiple types of
interchangeable tools may be collectively referred to as
"interchangeable tools 300". The robot apparatus 20 can perform
operations on workpieces W (i.e., workpiece Wa or Wb), which are
target objects, by using multiple types of interchangeable
tools.
[0044] The robot arm body 100 includes a base 101, six links 102 to
107, and six joints 111 to 116 that join the links 102 to 107 to
each other in such a manner that the respective links can turn in
the directions of arrows a to fin FIG. 1. The joints 111 to 116
have corresponding robot arm motors 121 to 126 that can turn the
links 102 to 107 (see FIG. 2). Each of the joints 111 to 116 has an
encoder (not illustrated) that detects the angular position of the
corresponding joint. The results are fed back to the control device
600.
[0045] As illustrated in FIG. 1, the base 101 and the link 102 of
the robot arm body 100 are connected to each other by the joint
111. The movement range of the joint 111 is assumed to be, for
example, approximately +/-180 degrees in the direction of arrow a
from the initial position.
[0046] The link 102 and the link 103 of the robot arm body 100 are
connected to each other by the joint 112. The movement range of the
joint 112 is assumed to be, for example, approximately +/-80
degrees in the direction of arrow b from the initial position.
[0047] The link 103 and the link 104 of the robot arm body 100 are
connected to each other by the joint 113. The movement range of the
joint 113 is assumed to be, for example, approximately +/-70
degrees in the direction of arrow c from the initial position.
[0048] The link 104 and the link 105 of the robot arm body 100 are
connected to each other by the joint 114. The movement range of the
joint 114 is assumed to be, for example, approximately +/-180
degrees in the direction of arrow d from the initial position.
[0049] The link 105 and the link 106 of the robot arm body 100 are
connected to each other by the joint 115. The movement range of the
joint 115 is assumed to be, for example, approximately +/-120
degrees in the direction of arrow e from the initial position.
[0050] The link 106 and the link 107 of the robot arm body 100 are
connected to each other by the joint 116. The movement range of the
joint 116 is assumed to be, for example, approximately +/-240
degrees in the direction of arrow f from the initial position.
[0051] As illustrated in FIG. 1, the interchangeable tool 300a is
attached to the link 107 that is located at the distal end of the
robot arm body 100. The interchangeable tool 300 that is supported
by the link 107 can move freely in the XYZ coordinate space in the
drawings in accordance with operation of the robot arm body 100.
The link 107 has a tool driving motor 221 (FIG. 2) for driving the
interchangeable tool 300a. The tool driving motor 221, for example,
opens/closes the interchangeable tool 300a so as to grip a target
object.
[0052] In a case in which assembling a product involves different
types of workpieces and different types of operations, various
interchangeable tools 300 are selected in accordance with
individual target objects W and work items. For example, multiple
interchangeable tools having different contact portions, which come
into contact with different types of target objects and accordingly
have different lengths and shapes, are provided in advance.
Appropriate operations can be performed on the target objects W by
selecting appropriate interchangeable tools 300 in accordance with
types of objects or types of works.
[0053] A tool stocker 500 is used to hold each interchangeable tool
300. For example, the interchangeable tool 300a is held by a tool
stocker 500a, and the interchangeable tool 300b is held by a tool
stocker 500b. Detailed description will be given later.
[0054] The pneumatic apparatus 400 supplies air to, or discharges
air from, the robot arm body 100 and the tool stocker 500. The
pneumatic apparatus 400 is constituted by an electromagnetic valve
421, a pressure sensor 422, and a compressor 423. The pneumatic
apparatus 400 operates when the interchangeable tool 300 is
attached to and detached from the robot arm body 100 and when the
tool stocker 500 holds the interchangeable tool 300.
[0055] The control device 600 includes a central processing unit
(CPU) 601, a read-only memory (ROM) 602 that stores a program, and
a random-access memory (RAM) 603. The control device 600 further
includes a communication interface (represented by I/F in the
drawings) 604 and other components. The RAM 603 is used to
temporarily store data, such as teaching points and control
commands from the external input device 700.
[0056] An example of the external input device 700 is a device such
as a teaching pendant (TP). However, the external input device 700
may be any other computer device (PC or server) that can edit a
robot program. The external input device 700 can be connected to
the control device 600 via a wired or wireless communication
device. The external input device 700 provides a user interface
functions for robot operation, displaying a status, or the
like.
[0057] The CPU 601 receives, via a communication interface 604,
teaching point data that are input by using, for example, the
external input device 700. The CPU 601 can also generate a moving
path for each of the shafts of the robot apparatus 20 in accordance
with the teaching point data that have been input from the external
input device 700, and the CPU 601 can transmit the moving path
data, as target control values, to the robot apparatus 20 via the
communication interface 604.
[0058] The control device 600 is also connected to the tool stocker
500 via the communication interface 604. This enables the control
device 600 to control the robot apparatus 20 and the tool stocker
500 integrally. Moreover, the control device 600 is connected to
the pneumatic apparatus 400 via the communication interface
604.
[0059] The pneumatic apparatus 400 supplies air to, or discharges
air from, the link 107 of the robot arm body 100 and the tool
stocker 500. This enables the interchangeable tool 300 to be
attached to, or detached from, the robot arm body 100 and
subsequently to be positioned in the tool stocker 500 for storage.
A detailed description will be given later.
[0060] FIG. 2 is a detailed block diagram illustrating a
configuration of a control system 10 of the robot system in FIG. 1.
The control device 600, which serves as a control section of the
robot system 10, controls robot arm motors 121 to 126 that are
installed in the respective joints 111 to 116 of the robot arm body
100. The control device 600 also controls a tool driving motor 221
installed in the link 107, the pneumatic apparatus 400, and the
tool stocker 500.
[0061] An arm motor driver 120 controls each of the robot arm
motors 121 to 126 on the basis of the control values obtained from
the control device 600 and thereby controls the position of the
robot arm body 100. Similarly, a tool driving motor driver 220
controls the tool driving motor 221 on the basis of the control
values obtained from the control device 600 and thereby controls
opening/closing of the interchangeable tool 300.
[0062] The pneumatic apparatus 400 drives the compressor 423 so as
to compress or release the air within a tank (not illustrated) on
the basis of instruction values from the control device 600. When
the pressure sensor 422 detects a predetermined air pressure, the
pneumatic apparatus 400 supplies air or discharges air by opening
or closing the electromagnetic valve 421. The electromagnetic valve
421 is formed so as to be able to supply air to, or discharge air
from, the link 107 and the tool stocker 500 separately.
[0063] Next, an attachment/detachment mechanism for the
interchangeable tool 300 and the robot arm body 100 according to
the present embodiment will be described with reference to FIGS. 3A
to 3C.
[0064] FIG. 3A is a perspective view of an attachment/detachment
mechanism disposed in the link 107. FIG. 3B is a perspective view
of the attachment/detachment mechanism disposed in the
interchangeable tool 300. FIG. 3C is a view illustrating a state in
which the interchangeable tool 300 is attached to the link 107.
[0065] As illustrated in FIGS. 3A and 3B, a pair of drive bases 211
are mounted on a mounting surface of the link 107 on which the
interchangeable tool 300 is mounted. A pair of the drive bases 211
are supported by a pair of slide guides 213 in such a manner that
the drive bases 211 are movable in the directions of arrow A and
arrow B. A pair of the drive bases 211 are formed such that the
tool driving motor 221 moves the drive bases 211 closer to, or away
from, each other by using a rack and pinion mechanism (not
illustrated).
[0066] The interchangeable tool 300 has a pair of finger support
bases 314. A pair of the finger support bases 314 are supported by
a slide guide mechanism in such a manner that the finger support
bases 314 can move closer to or away from each other in the
directions of arrow A and arrow B, which is similar to a pair of
the drive bases 211. A pair of the finger support bases 314 are
joined to a pair of corresponding fingers 330, which serve as
contact portions that come into contact with a target object. A
pair of the finger support bases 314, which move closer to or away
from each other, cause a pair of the fingers 330 to move closer to
or away from each other so as to grip or release a target
object.
[0067] A pair of the finger support bases 314 are disposed on a
mounting surface of the interchangeable tool 300 that faces the
link 107. The finger support bases 314 can move closer to or away
from each other along the slide guides 331 in the directions of
arrow A and arrow B in accordance with movement of a pair of the
drive bases 211 of the link 107. The finger support bases 314 are
integrally joined to the respective fingers 330 that pass through
openings 320 and protrude from the surface of the interchangeable
tool 300 opposite to the mounting surface. The fingers 330 serve as
contact portions that come into contact with a target object. The
finger support bases 314 that move closer to or away from each
other can cause the fingers 330 to open or close and thereby to
grip or release the target object.
[0068] In the state in which the interchangeable tool 300 is
attached to the link 107, drive transmission pins 212 disposed in
the drive bases 211 engage respective drive transmission holes 317
disposed in the finger support bases 314 (FIG. 3C). The drive
transmission pins 212 and the drive transmission holes 317 are
mechanically connected to each other.
[0069] As illustrated in FIG. 3C, a pair of the drive bases 211 are
moved closer to or away from each other in this state. This causes
a pair of the finger support bases 314 to move closer to or away
from each other, which causes a pair of the fingers 330 to move
closer to or away from each other and thereby grip or release a
target object W. The drive transmission pins 212 and the drive
transmission holes 317 serve as a drive transmission portion that
drives the fingers 330, which serve as the contact portions that
come into contact with a target object.
[0070] The finger support bases 314 have respective protruding
portions 319. The protruding portions 319 protrude when the
respective finger support bases 314 move in the directions of arrow
A and arrow B.
[0071] The link 107 has a pair of ball plangers 240, and the
interchangeable tool 300 has a pair of engagement holes 340. The
ball plangers 240 and the engagement holes 340 are disposed to
maintain the state of attachment of the interchangeable tool 300 to
the link 107. In the present embodiment, the ball planger 240 is a
type of ball planger that uses air for engagement. The air is
supplied to or discharged from the ball plangers 240 via a pair of
pipes 232. A pair of the pipes 232 are connected to the
above-described pneumatic apparatus 400. A pair of the ball
plangers 240 are inserted into a pair of the engagement holes 340
of the interchangeable tool 300. Ball members of the ball plangers
240 are pushed out by air, and the interchangeable tool 300 and the
link 107 engage each other. The ball plangers 240 and the
engagement holes 340 serve as a fixing portion that maintains the
state of attachment of the interchangeable tool 300 to the robot
arm body 100.
[0072] Note that in the present embodiment, the ball members are
moved by using air, but a spring or an electromagnetic valve may be
used to cause the ball members to move and engage each of the
engagement holes 340.
[0073] Other interchangeable tools 300 are also equipped with the
above-described attachment/detachment mechanism. Accordingly,
various interchangeable tools can be used to perform various
appropriate operations on a target object. The fixing portion and
the drive transmission portion are disposed on appropriate surfaces
of the interchangeable tool 300 and the link 107. Accordingly, the
interchangeable tool 300 can be attached or detached while the
robot arm body 100 moves the link 107 closer to or away from the
interchangeable tool 300 in a single direction.
[0074] Next, the tool stocker 500 that holds the interchangeable
tool 300 of the disclosure will be described with reference to
FIGS. 4A to 4C. FIG. 4A is a perspective view of a tool stocker 500
that does not hold the interchangeable tool 300. FIG. 4B is a
perspective view of the tool stocker 500 that holds the
interchangeable tool 300. FIG. 4C is the cross-section that is cut
along dash-dot-dot line IVC-IVC in FIG. 4B.
[0075] As illustrated in FIG. 4A, the tool stocker 500 has an
opening 512 provided in a contact surface 511 that comes into
contact with the interchangeable tool 300 when the tool stocker 500
holds the interchangeable tool 300. The fingers 330 are inserted
into the opening 512. The tool stocker 500 is installed on a
stocker-inclining member 561 in such a manner that the contact
surface 511 is inclined with respect to a floor surface so as to
face obliquely upward. The stocker-inclining member 561 maintains
the surface of the interchangeable tool 300 that comes into contact
with the link 107 in a state in which the surface faces obliquely
upward.
[0076] Disposed on the contact surface 511 are a pair of pins 514,
a pair of ball plangers 517, a pair of pressing mechanisms 530, an
identification sensor 560, and presence/absence sensors 570 of a
light transmissive type.
[0077] Each of the pins 514 includes a diameter expansion member
that can expand and contract the diameter of the pin by using air.
The pins 514 are connected to the pneumatic apparatus 400 (see FIG.
2) by piping (not illustrated), and the diameter expansion member
is expanded or contracted by supplying or discharging air. A pair
of the ball plangers 517 are formed similarly to the
above-described ball plangers 240.
[0078] Each of the pressing mechanisms 530 is formed of a lever
member 532 that is turnably disposed and a spring member 533. The
spring member 533 engages an end of the lever member 532, thereby
elastically urging the lever member 532 to turn in the direction of
arrow G.
[0079] A roller 535 is attached to the lever member 532. The roller
535 comes into contact with each of the protruding portions 319. A
pair of the lever members 532, which are urged to turn in the
directions of arrow G by the spring members 533, press the
protruding portions 319. The lever members 532 thereby position the
finger support bases 314. A detailed description will be given
below.
[0080] As illustrated in FIG. 4A, the lever member 532 is turned
around a lever turning axis 534 in the direction of arrow G due to
the spring member 533 pulling the lever member 532. The lever
member 532 moves the roller 535 upward in the direction of arrow G
simultaneously. When the tool stocker 500 does not hold the
interchangeable tool 300, the tool stocker 500 stays in the state
in FIG. 4A.
[0081] FIG. 4B is a view illustrating the state in which the tool
stocker 500 holds the interchangeable tool 300. The interchangeable
tool 300 has holes at positions corresponding to the pins 514 and
the ball plangers 517. The diameter expansion members of the pins
514 expand outward and come into close contact with the respective
holes, which thereby fixes the position of the interchangeable tool
300 in the X and Y directions. In addition, the ball plangers 517
engage the respective holes of the interchangeable tool 300 and
expand outward, which thereby fixes the position of the
interchangeable tool 300 in the Z direction. Thus, the pins 514 and
the ball plangers 517 serve as a positioning mechanism to position
the interchangeable tool 300 and retain the position.
[0082] As illustrated in FIG. 4C, in the state of the
interchangeable tool 300 being held, the spring members 533
elastically urge the pressing mechanisms 530 to turn around the
respective lever turning axes 534 in the directions of arrow G. The
rollers 535 are brought into contact with the respective protruding
portions 319 and press the protruding portions 319 continuously in
the directions of arrow K. Since the protruding portions 319 are
integral to the respective finger support bases 314, the finger
support bases 314 are thereby brought into contact with abutting
portions 320a that are formed at inner edges of the openings
320.
[0083] As a result, the finger support bases 314 and the drive
transmission holes 317 are placed at appropriate positions, and the
positions are maintained. Even if the interchangeable tool 300 are
held by the tool stocker 500 in an inclined manner because of the
stocker-inclining member 561, the interchangeable tool 300 is
positioned appropriately. Accordingly, the positioning mechanism
reduces the likelihood of the drive transmission holes 317
deviating from the drive transmission pins 212 of the link 107 when
the interchangeable tool 300 is attached to the link 107.
[0084] Returning to FIG. 4A, the identification sensor 560 is a
proximity sensor that outputs a signal when an object comes to a
predetermined position. The interchangeable tool 300 has an
identification portion 347 (FIG. 3B) disposed at a position
opposing the identification sensor 560 when the interchangeable
tool 300 is held by the tool stocker 500. When the interchangeable
tool 300 is held on the tool stocker 500, the identification
portion 347 comes close to the identification sensor 560 and
reaches the predetermined position (FIG. 4B).
[0085] When this occurs, the identification sensor 560 transmits an
"ON" signal to the control device 600, and the control device 600
determines that the interchangeable tool 300 is held by the
corresponding tool stocker 500 appropriately. On the other hand,
when an inappropriate interchangeable tool 300 is held and it does
not have the identification portion 347 at the position opposing
the identification sensor 560, the signal transmitted from the
identification sensor 560 to the control device 600 remains in an
"OFF" state, and the control device 600 recognizes that a wrong
interchangeable tool 300 is held by the tool stocker 500.
[0086] The type of interchangeable tool 300 that is held by the
tool stocker 500 can be determined by associating the combination
of the positions of the identification portion 347 and the
identification sensor 560 with the combination of the
interchangeable tool 300 and the tool stocker 500.
[0087] The presence/absence sensors 570 are light transmissive
sensors, and an optical path extends between the presence/absence
sensors 570. Since the interchangeable tool 300 blocks the optical
path between the presence/absence sensors 570 in the state in FIG.
4B, the control device 600 recognizes that the interchangeable tool
300 is held on the tool stocker 500.
[0088] On the other hand, in the state in FIG. 4A, the control
device 600 recognizes that the interchangeable tool 300 is not held
on the tool stocker 500 since the optical path between the
presence/absence sensors 570 is not blocked.
[0089] Next, arrangement of the above-described tool stockers 500
will be described with reference to FIG. 5. FIG. 5 is a layout of
the tool stockers 500 according to the present embodiment. The
stocker-inclining member 561 has a surface that inclines with
respect to a floor surface 565. The tool stocker 500 is installed
on the surface of the stocker-inclining member 561 in such a manner
that the contact surface 511 of the tool stocker 500 faces
obliquely upward.
[0090] Two tool stockers 500a and 500b are installed on top of the
stocker-inclining member 561 and are joined by fixing members 562.
For convenience of description, in the image of FIG. 5, the tool
stocker located at the bottom is referred to as the "tool stocker
500b", and the tool stocker located at the top is referred to as
the "tool stocker 500a". The tool stockers 500a and 500b hold
interchangeable tools 300a and 300b, respectively. Tools 564 to be
used for assembling work by the robot apparatus 20 are disposed in
the vicinity of the tool stockers 500.
[0091] As illustrated in FIG. 5, when the tool stocker 500a is
disposed on top of the tool stocker 500b, the tool stocker 500a is
joined to the tool stocker 500b in such a manner that the
respective contact surfaces 511 are shifted from each other. In
other words, the position of the contact surface 511 of the tool
stocker 500a, which is represented by dotted line a, is not
coincident with the position of the contact surface 511 of the tool
stocker 500b, which is represented by dotted line b.
[0092] FIG. 6 is a perspective view of the tool stockers 500 when
viewed from behind the tool stockers 500. Inverse T-shaped grooves
563 are provided in the stocker-inclining member 561, the tool
stocker 500a, and the tool stocker 500b. The fixing members 562 are
movable along the inverse T-shaped grooves 563 in the direction of
arrow F. A detailed description will be given below.
[0093] FIG. 7 is a cross-sectional view illustrating a fixing
member 562 and a groove 563. FIG. 7 is a cross section that is cut
along dash-dot-dot line VII-VII in FIG. 6 and is viewed from a YZ
plane. The inverse T-shaped grooves 563 are provided in each of the
tool stockers 500. The groove 563 illustrated in FIG. 7 is the one
provided in the tool stocker 500b.
[0094] The fixing member 562 is fixed to the tool stocker 500a by
using a bolt 567. A nut 568 is disposed in the groove 563 and
guided by an expanded portion 563b so as to be able to slide along
the groove 563 in the F direction in FIG. 6.
[0095] As illustrated in FIG. 7, the fixing member 562 and the tool
stocker 500b is nipped by the bolt 569 and the nut 568. Loosening
the bolt 569 and the nut 568 enables the fixing member 562 to slide
along the groove 563.
[0096] The fixing member 562 can be fixed at an arbitrary position
along the groove 563 by tightening the bolt 569 and the nut 568
thoroughly so as to screw the bolt 569 into the expanded portion
563b. Thus, the tool stocker 500a can be fixed at an arbitrary
position. The attaching/detaching position of the interchangeable
tool 300 and the robot arm body 100 can be thereby set at an
arbitrary position in a direction in which the contact surface 511
and the mounting surface of the robot arm move closer to or away
from each other. The mechanism that is constituted by the bolt and
nut serves as a position adjustment mechanism.
[0097] The position adjustment mechanism is capable of changing the
position of the contact surface 511 of each tool stocker and also
changing the attaching/detaching position of the interchangeable
tool 300 and the robot arm body 100. The bolts 567 and 569 and the
nut 568 also serve as a coupling mechanism that joins the tool
stocker 500a and the tool stocker 500b to each other. Note that
although the above description is focused on the connection between
the tool stocker 500a and the tool stocker 500b, a similar
mechanism is applied to the fixing member 562 that joins the tool
stocker 500b to the stocker-inclining member 561. Also note that
instead of the mechanism using the bolt and nut, another mechanism,
such as a rack and pinion or a slide guide, is applicable insofar
as such a mechanism enables sliding movement in a single direction
and fixation at an arbitrary position.
[0098] As described above, the tool stocker according to the
present embodiment is installed in such a manner that the contact
surface is inclined with respect to the supporting surface (i.e.,
floor surface) so as to face obliquely upward. In other words, the
tool stocker is installed in such a manner that the contact surface
faces the robot arm body 100 that has a range of motion extending
above the level of the tool stocker. This is advantageous in an
environment in which the robot arm is installed. A detailed
description will be given below.
EXAMPLE 1
[0099] FIGS. 8A and 8B are comparative illustrations to be used for
describing advantageous effects of the robot system 10 with tool
stocker arrangement according to the present embodiment. FIG. 8A is
a view illustrating a state in which the tool stockers 500 are
stacked in the Z direction with respect to the floor surface 565
while the X direction is parallel to the direction of attaching and
detaching the interchangeable tool 300 to and from the robot arm
body 100. FIG. 8B is a view illustrating a state in which the tool
stockers 500 are placed in a row parallel to the floor surface 565.
Dash-dot line R in FIGS. 8A to 8D indicates the maximum range of
motion of the robot arm body 100.
[0100] As illustrated in FIG. 8A, when the tool stockers 500 are
stacked in the vertical direction with respect to the floor surface
565, in other words, in the Z direction, the attaching/detaching
direction is parallel to the X direction. In this case, the
footprint of the tool stockers on the floor surface 565 can be
reduced. However, when the link 107 takes the tool held by the
bottommost tool stocker, the link 107 takes the tool with the
position of the link 107 indicated by the dotted line in FIG. 8A.
Consequently, a space for operations performed on the target
objects Wa and Wb is not available near the tool stockers 500. As a
result, the workspace in which the target object Wa and Wb are
placed is inevitably disposed away from the attaching/detaching
position of the interchangeable tool 300 and the robot arm body
100, which leads to longer operating time.
[0101] As illustrated in FIG. 8B, when the tool stockers 500 are
disposed in a raw parallel to the floor surface 565, in other
words, in the X direction, the attaching/detaching direction is
parallel to the Z direction. In this case, a space occupied by the
tool stocker 500 in the Z direction can be reduced. However,
placing target objects at a high position in the gravity direction
(for example, assembling work carried out on a place such as a
wall) is not common because this requires assembling work to be
carried out against the gravity. Accordingly, the workspace becomes
inevitably narrower compared with the case in FIG. 8A.
[0102] On the other hand, when the tool stockers 500 according to
the present embodiment are arranged as illustrated in FIG. 8C, each
contact surface 511 of the tool stockers 500 can be inclined and
the position of each contact surface 511 is adjustable.
Accordingly, the attaching/detaching position of the
interchangeable tools 300 and the robot arm body 100 can be
adjusted to fit the maximum range of motion of the robot arm body
100.
[0103] As a result, the link 107 can take the tool held by the
bottommost tool stocker with the position of the link 107 indicated
by the dotted line in FIG. 8C, and a space that cannot be used in
the case in FIG. 8A becomes now available for the workspace.
[0104] In addition, the attaching/detaching position of the
interchangeable tools 300 and the robot arm body 100 can be changed
by arranging the tool stockers. The attaching/detaching position
can be adjusted to fit the moving path of the robot arm body 100 by
arranging the tool stockers. The moving path can be generated
independent of the attaching/detaching position.
[0105] This relaxes constraints on the moving path of the robot arm
body 100 and thereby provides more freedom and easiness to decide
moving paths of the robot arm so as to shorten operation time.
[0106] Moreover, since the tool stockers are stacked in the Z
direction, the footprint of the tool stockers on the floor surface
565 can be reduced compared with the case in FIG. 8B. Thus, a
larger workspace for the robot arm body 100 is made available.
[0107] As described above, by using the tool stockers 500 according
to the present embodiment, the attaching/detaching position of the
interchangeable tool 300 and the robot arm body 100 can fit the
range of motion of the robot arm body 100. This can make a larger
workspace available and can provide more freedom in arranging
target objects and tools disposed in the workplace as well as in
deciding the moving paths of the robot arm body 100. This can
improve work efficiency without sacrificing workspace.
[0108] As illustrated in FIG. 8D, the tool stockers 500 may be
disposed on a ceiling 580. As described above, a pair of the pins
514 and a pair of the ball plangers 517 provided in the tool
stocker 500 serve as the positioning mechanism. The positioning
mechanism positions and fixes the interchangeable tool 300 and
thereby prevents the interchangeable tool 300 from falling. In the
case in FIG. 8D, a sill larger workspace is made available for
disposing tools, such as large-size tools 564 as illustrated in
FIG. 8C.
MODIFICATION EXAMPLE 1
[0109] Next, modification examples of the first embodiment will be
described. In the first embodiment, the pneumatic apparatus 400
supplies air to, or discharges air from, both the robot arm body
100 and the tool stocker 500. However, the disclosure can be
implemented with a configuration in which the pneumatic apparatus
400 supplies air only to the tool stocker 500. A detailed
description will be given below.
[0110] In the following description, part of a hardware
configuration and a control system configuration that are different
from those in the first embodiment will be described with reference
to the drawings. In modification example 1, the ball planger 240
and the tool stocker 500 according to the first embodiment are
altered partially. The elements similar to those in the first
embodiment have similar configurations and operate similarly, and
accordingly a detailed description on the elements will be omitted.
In addition, members or control functions same as, or similar to,
those in the first embodiment are denoted by the same reference
symbols.
[0111] As illustrated in FIG. 9, in the present modification
example, a pair of the ball plangers 240 are joined to each other
by a frame 245. In addition, a coupling portion 244 is disposed in
the frame 245. The coupling portion 244 includes a built-in valve
for supplying air to actuate a pair of the ball plangers 240.
[0112] FIG. 10 is a perspective view illustrating a state in which
the interchangeable tool 300 is held by a tool stocker 500
according to the present modification example. The main difference
between the present modification example and the first embodiment
is that in the present modification example, the tool stocker 500
has a coupling portion 525 that will be coupled to the coupling
portion 244 having a valve through which air passes. The coupling
portion 525 is connected to the pneumatic apparatus 400 via piping
(not illustrated).
[0113] FIG. 11 is a cross-sectional view illustrating a state in
which the robot arm body 100 takes the interchangeable tool 300
that is held on the tool stocker 500. FIG. 11 is a cross section
that is cut along dash-dot-dot line XI-XI in FIG. 10. The robot arm
body 100 moves the link 107 straight in the direction of arrow C.
Subsequently, the ball plangers 240 are inserted into the
engagement holes 340 of the interchangeable tool 300.
[0114] Simultaneously, the coupling portion 244 and the coupling
portion 525 are coupled to each other. At this time, respective
valves disposed in the coupling portions 244 and 525 open and
thereby establish an air connection through which air is supplied
to or discharged from the inside of the frame 245 via the piping.
Supplying air to or discharging air from the ball plangers 240
moves the ball members and causes the ball members to engage or
disengage the engagement holes 340. The interchangeable tool 300 is
thereby attached to or detached from the link 107.
[0115] When the interchangeable tool 300 is attached or detached,
the coupling portion 525 of the tool stocker 500 receives a force
applied by the link 107. The coupling portion 525 is disposed on
the contact surface 511 at a position close to the floor surface
565. This can reduce a moment that is generated by a force applied
from the link 107 during attachment/detachment and is transferred
to the floor surface 565. Accordingly, bending deformation of the
tool stocker 500 can be suppressed.
[0116] The ball plangers are actuated by supplying or discharging
air via the coupling portions 244 and 525, which eliminates the
necessity of disposing pipes 232 for air delivery in the robot arm
body 100 and can thereby reduce manufacturing cost. The piping is
disposed in the tool stocker 500 instead of disposing in the robot
arm body 100 that moves frequently. This can reduce the likelihood
of damage occurring in the piping. Thus, air can be supplied and
discharged reliably.
MODIFICATION EXAMPLE 2
[0117] In the first embodiment and in modification example 1, the
pressing mechanisms 530 is formed such that the spring members 533
urge the respective lever members 532 that are made turnable and
the lever members 532 press the respective protruding portions 319
of the finger support bases 314 when the tool stocker 500 holds the
interchangeable tool 300.
[0118] However, the pressing mechanisms 530 may be arbitrarily
replaced with any other mechanisms that press the finger support
bases 314 in predetermined directions. For example, a
piston-cylinder actuated by air may be used as the pressing
mechanisms 530. For example, each roller 535 is connected to a
piston-cylinder that is actuated by air, and air is supplied to the
cylinder and actuates the roller 535 in the pressing direction when
the tool stocker 500 holds the interchangeable tool 300. This can
provide the same effect as in the case of using the lever
members.
[0119] Moreover, as illustrated in FIGS. 12A to 12C, the pressing
mechanisms 530 may be disposed below the level of the contact
surface 511 in the tool stocker 500 instead of disposing the
pressing mechanisms 530 on the contact surface 511. FIGS. 12A to
12C illustrate the interchangeable tool 300 and the tool stocker
500 in the case in which the pressing mechanisms 530 is disposed
under the contact surface 511. FIG. 12A illustrates the
interchangeable tool 300, and FIG. 12B illustrates the tool stocker
500. FIG. 12C is a cross-sectional view illustrating the state in
which the interchangeable tool 300 is held by the tool stocker
500.
[0120] As illustrated in FIG. 12A, protruding portions 319 are
integrally formed with respective fingers 330. As illustrated in
FIG. 12B, the pressing mechanisms 530 are disposed under the
contact surface 511 (at a position in the -Z direction).
[0121] As illustrated in FIG. 12C, the rollers 535 of the pressing
mechanisms 530 come into contact with the respective protruding
portions 319, thereby pressing the fingers 330 in the corresponding
directions of arrow K. This can provide the same effect as in the
case in which the pressing mechanisms 530 are disposed on the
contact surface 511 (at a position in the +Z direction).
[0122] In addition, as illustrated in FIGS. 13A to 13B, tapered
portions may be disposed in place of the pressing mechanisms 530.
FIGS. 13A to 13B are cross-sectional views illustrating the
interchangeable tool 300 and the tool stocker 500 in the case in
which tapered members 540 are provided in place of the pressing
mechanisms 530.
[0123] As illustrated in FIG. 13A, the fingers 330 of the
interchangeable tool 300 have respective tapered contact portions
350 in place of the protruding portions 319. The tapered contact
portions 350 come into contact with the corresponding tapered
portions 540.
[0124] As illustrated in FIG. 13B, the tapered contact portions 350
of the interchangeable tool 300 come into contact with the
corresponding tapered portions 540 of the tool stocker 500 when the
tool stocker 500 holds the interchangeable tool 300.
[0125] The fingers 330 slide in the respective directions of arrow
S due to tapered portions in contact with other tapered portions.
The finger support bases 314 moves in the respective directions of
arrow K simultaneously. The finger support bases 314 are positioned
to appropriate positions by abutting the inner edges of the
openings 320 of the interchangeable tool 300. The tapered contact
portions 350 serve as a position regulating portion, and the
tapered portions 540 serve as a positioning mechanism.
[0126] With this configuration, the finger support bases 314 can be
positioned to appropriate positions and the positions can be
maintained without using the lever members and the spring members.
This can simplify the positioning mechanism to be disposed in the
tool stocker 500, which leads to cost reduction.
Second Embodiment
[0127] In the first embodiment, the attaching/detaching position of
the interchangeable tool 300 is fitted to the moving paths of the
robot arm body 100 by arranging the tool stockers 500. Work
efficiency is improved by increasing the degree of freedom of the
moving paths of the robot arm body 100. However, in the present
embodiment, work efficiency can be further improved by arranging
workpieces on which the robot arm body 100 performs operations.
[0128] In the following description, part of a hardware
configuration and a control system configuration that are different
from those in the first embodiment will be described with reference
to the drawings. The elements similar to those in the first
embodiment have similar configurations and operate similarly, and
accordingly a detailed description on the elements will be omitted.
In addition, members or control functions same as, or similar to,
those in the first embodiment are denoted by the same reference
symbols.
[0129] FIG. 14 is a view schematically illustrating a robot system
10 according to the present embodiment. The major difference
between the first embodiment and the present embodiment is that a
parts-supplying apparatus 900 is disposed in the tool stocker 500
in the present embodiment. A detailed description will be given
below.
[0130] As illustrated in FIG. 14, the parts-supplying apparatus 900
conveys a workpiece Wc to a position at which the interchangeable
tool 300c held by the tool stocker 500c can grip the workpiece Wc.
The parts-supplying apparatus 900 that corresponds to the workpiece
Wc is hereinafter referred to as the "parts-supplying apparatus
900c". The parts-supplying apparatus 900c is disposed directly
under the tool stocker 500c.
[0131] FIG. 15 is a detailed block diagram illustrating a
configuration of a control system of the robot system 10 in FIG. 1.
The control device 600 according to the present embodiment not only
controls the tool stocker 500 and the pneumatic apparatus, as in
the first embodiment, but also controls the parts-supplying
apparatus 900c.
[0132] The parts-supplying apparatus 900c includes a parts supply
control circuit 910c, a parts conveyor unit 901c, and a parts
locator mechanism 902c. In response to instruction values sent from
the control device 600, the parts supply control circuit 910c
drives and controls the parts conveyor unit 901c and the parts
locator mechanism 902c. The parts supply control circuit 910c
drives the parts locator mechanism 902c so as to set and place the
workpiece Wc at any arbitrary position.
[0133] FIG. 16 is a perspective view of the interchangeable tool
300c according to the present embodiment. As compared to the
configuration in the first embodiment, the major difference resides
in fingers 330c. The fingers 330 in the first embodiment are shaped
like rectangular columns. The fingers 330c are also shaped like
rectangular columns but have claw-shaped tips.
[0134] The attachment/detachment mechanism for the interchangeable
tool 300a and the robot arm body 100, which has been described in
the first embodiment with reference to FIGS. 3A to 3C, is also
disposed in the interchangeable tool 300c. Accordingly, the
interchangeable tool 300c can be attached to the robot arm body 100
readily.
[0135] FIG. 17 is a perspective view illustrating the
parts-supplying apparatus 900c and the tool stockers 500c according
to the present embodiment. To simplify the description, the
stocker-inclining member 561 that are used in the first embodiment
and the position adjustment mechanism that includes the bolt 569
and the nut 568 are omitted. The stocker-inclining member 561 and
the position adjustment mechanism may be provided to the
parts-supplying apparatus 900c. Parts can be thereby supplied to
the interchangeable tool 300c that is inclined and held by the tool
stocker 500c as in the first embodiment.
[0136] As illustrated in FIG. 17, the workpiece Wc is a parallel
pin shaped like a cylinder. The parts-supplying apparatus 900c is
disposed directly under the tool stocker 500c. The parts-supplying
apparatus 900c conveys workpieces Wc in a row in the direction of
arrow P.
[0137] FIG. 18 is a view illustrating the parts-supplying apparatus
900c in detail. As illustrated in FIG. 18, the parts conveyor unit
901c of the parts-supplying apparatus 900c arranges workpieces Wc
in a row and conveys the workpieces Wc in the direction of arrow P.
In the present embodiment, a belt conveyor is used as the parts
conveyor unit 901c.
[0138] Note that in the case in which the parts-supplying apparatus
900c is inclined, a slip prevention device, such as a pressure
sensitive adhesive sheet, may be appropriately used in the parts
conveyor unit 901c so as to prevent the workpieces Wc from falling
off by their own weight.
[0139] As illustrated in FIG. 18, each of the workpieces Wc
conveyed by the parts conveyor unit 901c is placed in the parts
locator mechanism 902c. When a sensor 903c of the parts locator
mechanism 902c detects a workpiece Wc, a signal is sent to the
parts supply control circuit 910 to stop the parts conveyor unit
901c.
[0140] The sensor 903c, which detects presence or absence of a
workpiece Wc in the parts locator mechanism 902c, is built in the
parts locator mechanism 902c. The sensor 903c detects the weight of
a workpiece Wc.
[0141] These points described above are major differences of the
present embodiment compared with the first embodiment. In the
present embodiment, when the tool stocker 500c holds the
interchangeable tool 300c, the pressing mechanisms 530 press the
protruding portions 319 and thereby position the fingers 330c to
the appropriate positions and maintain the position. In other
words, the interchangeable tool 300c grips a workpiece Wc and
maintains the gripping state while the interchangeable tool 300c is
held by the tool stocker 500c.
[0142] With this configuration, gripping of a workpiece and
attachment/detachment of the interchangeable tool are performed
simultaneously, which can reduce the number of steps that the robot
arm body performs and thereby improve work efficiency.
[0143] Moreover, the workpiece Wc can be gripped without using the
robot arm body 100. With this configuration, gripping accuracy can
be improved since disturbance such as vibrations from the robot arm
body 100 can be excluded. Note that the pressing mechanisms 530 are
an example of the positioning mechanism. In addition, the
protruding portions 319 are an example of the position regulating
portion that regulates the respective positions of the contact
portions.
[0144] FIG. 19 is a flowchart when the tool stocker 500c holds the
interchangeable tool 300c according to the present embodiment while
the interchangeable tool 300c grips a workpiece Wc. FIGS. 20A to
20F are views each of which illustrates a state corresponding to
each step in FIG. 19. The processing flow of the flowchart
illustrated in FIG. 19 is initiated when the control device 600
issues an instruction to operate with the interchangeable tool
300c.
[0145] As illustrated in FIG. 19, in step S201, a workpiece Wc is
disposed in the parts locator mechanism 902c. Here, the workpiece
Wc is set to a position at which the interchangeable tool 300c can
grip the workpiece Wc in the state in which the interchangeable
tool 300c is held by the tool stocker 500c (FIG. 20A).
[0146] As illustrated in FIG. 20A, when the interchangeable tool
300c is not held by the tool stocker 500c, each of the lever
members 532 is turned around the lever turning axis 534 in the
direction of arrow G due to the spring member 533 pulling the lever
member 532 in the direction of arrow F, and the roller 535 is
raised in the direction of arrow G simultaneously.
[0147] In step S202, the interchangeable tool 300c attached to the
link 107 is moved to a region above the tool stocker 500c that
corresponds to the interchangeable tool 300c (FIG. 20B).
[0148] In step S203, the link 107 is moved straight in the
direction of arrow C, which thereby moves the fingers 330c closer
to the tool stocker 500c. The protruding portions 319 are
subsequently brought into contact with the respective rollers 535
at points P (FIG. 20C).
[0149] Further movement of the link 107 in the direction of arrow C
causes the interchangeable tool 330c to press the lever members 532
at respective points P in the directions of arrow H. The lever
members 532 turn around the respective lever turning axes 534 in
the corresponding directions of arrow I.
[0150] In step S204, the pressing mechanisms 530 press the fingers
330c in the respective directions of arrow K, thereby causing the
fingers 330c to grip the workpiece Wc and to maintain the gripping
state (FIG. 20D). The spring members 533 and the lever members 532
are adjusted such that the pressure applied at this moment by the
pressing mechanisms 530 becomes similar to the gripping pressure
when the interchangeable tool 300c grips the workpiece Wc.
[0151] In step S206, whether the operation with the interchangeable
tool 300c is finished or not is determined. If YES in step S206,
the processing proceeds to step S207. If NO in step S206, the
processing proceeds to step S208.
[0152] If YES in step S206, the operation with the interchangeable
tool 300c is finished. Consequently, in step S207, the
interchangeable tool 300c is released from the robot arm body 100
and held by the tool stocker 500c (FIG. 20E). At this moment, the
interchangeable tool 300c is detached from the link 107 of the
robot arm body 100 by using the attachment/detachment mechanism
described in relation to FIGS. 3A to 3C in the first
embodiment.
[0153] The interchangeable tool 300c is held by the tool stocker
500c with the interchangeable tool 300c gripping the workpiece Wc.
When performing the next operation with the workpiece Wc, the
workpiece Wc can be gripped simultaneously with the link 107 of the
robot arm body 100 taking the interchangeable tool 300c.
[0154] If NO in step S206, the operation with the interchangeable
tool 300c continues. Consequently, in step S208, the fingers 330c
grips the workpiece Wc by driving the tool driving motor 221 in the
link 107.
[0155] In step S209, the robot arm body 100 is moved in the
direction of arrow D and takes out the workpiece Wc from the parts
locator mechanism 902c for further operation on the workpiece Wc
(FIG. 20F). The processing returns to step S201, and the next
workpiece Wc is disposed in the parts locator mechanism 902c. The
processing flow in FIG. 19 is repeated until the operation with the
interchangeable tool 300c is finished.
[0156] As described above, according to the present embodiment,
attachment of the interchangeable tool 300c and gripping of a
workpiece Wc can be performed substantially simultaneously. This
eliminates the necessity of the robot arm body 100 moving to a
position at which a workpiece Wc is supplied and gripped after the
interchangeable tool 300c is attached to the robot arm body 100.
This reduces the time required for production and thereby improves
work efficiency.
[0157] Moreover, the state of gripping the workpiece Wc by the
fingers 330c can be achieved without using the tool driving motor
221 disposed in the robot arm body 100. When the workpiece Wc and
the fingers 330c come into contact with each other, disturbance
such as vibrations from the robot arm body 100 can be excluded, and
thus gripping accuracy can be improved.
[0158] The present embodiment is effective for such a workpiece
that frequency of gripping is low but high gripping accuracy is
demanded. Workpieces that demand low frequency and high accuracy of
gripping are disposed in such a manner as described with the
workpiece We in the present embodiment, while workpieces that
demand high frequency and low accuracy of gripping are disposed,
for example, on a pallet.
[0159] Thus, the workpieces that demands high frequency and low
accuracy of gripping are gripped and operated on by other
interchangeable tools, while the workpieces that demands low
frequency and high accuracy of gripping are gripped and operated on
by using the method described in the present embodiment. As a
result, the robot system can be controlled in accordance with the
gripping frequency and gripping accuracy for a workpiece, and
production efficiency can be thereby improved.
Third Embodiment
[0160] In the first embodiment and the second embodiment, as
described above, the pressing mechanisms of the tool stocker cause
the fingers to be positioned or cause the fingers to grip a
workpiece. However, a motor for driving the interchangeable tool
may be disposed in the interchangeable tool and the motor may drive
the fingers. A detailed description will be given below.
[0161] In the following description, part of a hardware
configuration and a control system configuration that are different
from those in the first and second embodiments will be described
with reference to the drawings. The elements similar to those in
the first and second embodiments have similar configurations and
operate similarly, and accordingly a detailed description on the
elements will be omitted. In addition, members or control functions
same as, or similar to, those in the first and second embodiments
are denoted by the same reference symbols.
[0162] FIG. 21 is a view schematically illustrating a robot system
10 according to the present embodiment. The major difference
between the present embodiment and the first and second embodiments
reside in the attachment/detachment mechanism for the
interchangeable tool 300 and the robot arm body 100, the structure
of the interchangeable tool 300, and the structure of the tool
stocker.
[0163] As illustrated in FIG. 21, an attachment/detachment
mechanism 250 is disposed in the link 107 of the robot arm body
according to the present embodiment, and the tool driving motor 221
is disposed in an interchangeable tool 300c'. In the following
description, the interchangeable tool 300c used in the second
embodiment is taken as an example of the interchangeable tool
according to the present embodiment, which will be referred to as
an "interchangeable tool 300c'" to avoid confusion.
[0164] The tool stocker 500c used in the second embodiment is also
taken as an example of the tool stocker according to the present
embodiment, which will be referred to as a "tool stocker
500c'".
[0165] FIGS. 22A to 22B are diagrams illustrating the robot arm
body 100 and the interchangeable tool 300c' according to the
present embodiment. FIG. 22A illustrates a mounting portion of the
robot arm body 100 to which an interchangeable tool is attached,
and FIG. 22B illustrates the interchangeable tool 300c'.
[0166] As illustrated in FIG. 22A, the interchangeable tool 300c'
is attached to the link 107 that is located at the end of the robot
arm body 100. The link 107 has the attachment/detachment mechanism
250 that can attach/detach the interchangeable tool 300c' and also
has an electrical connection portion 251 of the robot arm.
[0167] As illustrated in FIG. 22B, the interchangeable tool 300c'
has a coupling mechanism 301 that can be coupled to the
attachment/detachment mechanism 250 of the link 107 and also has an
electrical connection portion 302 disposed on the surface of the
interchangeable tool 300c' that comes into contact with the robot
arm body 100.
[0168] Moreover, the interchangeable tool 300c' includes two
fingers 330c that oppose each other with a central axis 315
interposed therebetween and the tool driving motor 221 that drives
the fingers 330c.
[0169] In the present embodiment, the tool driving motor 221 is
connected to the fingers 330c via a rack and pinion mechanism or
reduction gears (not illustrated). By using such a mechanism, the
tool driving motor 221 causes mutually opposing two fingers 330c to
move closer to or away from each other with respect to the central
axis 315. The fingers 330c can thereby grip or release a workpiece.
The fingers 330c serve as contact portions that come into contact
with a workpiece Wc.
[0170] Note that in place of the rack and pinion mechanism, any
other power transmission mechanism, such as a cam mechanism, that
transmits the power of the tool driving motor 221 to the fingers
330c may be used insofar as adopting such a mechanism does not
depart from the scope of the invention.
[0171] The interchangeable tool 300c' has an electrical connection
portion 307, which is another electrical connection portion
disposed on the surface that comes into contact with the tool
stocker 500c'. Details will be described later.
[0172] The interchangeable tool 300c' also has a positioning hole
306 for positioning of the interchangeable tool 300c' when mounted
on the tool stocker 500c'.
[0173] FIG. 23 is a diagram illustrating the state in which the
interchangeable tool 300c' is attached to the link 107 in the
present embodiment.
[0174] As illustrated in FIG. 23, the attachment/detachment
mechanism 250 of the link 107 has a seating face 254 of the robot
arm, an engagement shaft 253, and a plurality of balls 252 disposed
in the circumferential surface of the engagement shaft 253.
[0175] The coupling mechanism 301 of the interchangeable tool 300c'
has a seating face 391 of the interchangeable tool, an engagement
hole 392, and a tapered surface 393.
[0176] The engagement shaft 253 is connected to a pipe 232 that is
disposed through the inside of the robot arm body 100 and connected
to the pneumatic apparatus 400. The compressed air supplied or
discharged by pneumatic apparatus 400 through the pipe 232 causes
the balls 252 disposed in the engagement shaft 253 to move in the
radial direction of the engagement shaft 253 toward the inner
peripheral surface of the engagement hole 392.
[0177] When the balls 252 move outward in the radial direction
while the engagement shaft 253 engages the engagement hole 392, the
balls 252 abut the tapered surface 393 of the interchangeable tool
300c'.
[0178] The balls 252 press the tapered surface 393 and causes the
seating face 391 of the interchangeable tool to press the seating
face 254 of the robot arm. The interchangeable tool 300c' and the
link 107 are thereby coupled to each other mechanically.
[0179] Note that the pneumatic apparatus is the same as that used
in the first and second embodiments.
[0180] When the interchangeable tool 300c' and the link 107 are
mechanically coupled to each other, the electrical connection
portion 302 of the interchangeable tool is connected to the
electrical connection portion 251 of the robot arm. The electrical
connection portion 251 of the robot arm is connected to electric
wiring 30 that is disposed through the inside of the links 101 to
107 and is connected to the control device 600.
[0181] The tool driving motor 221 receives electric power from the
control device 600 through the wiring 30 once the connection is
established between the electrical connection portion 302 of the
interchangeable tool and the electrical connection portion 251 of
the robot arm. Signals also can be transmitted and received via the
wiring 30.
[0182] The control device 600 thereby controls the open and close
positions of the fingers 330c, causes the fingers 330c to grip a
target object, and performs any suitable operation on the target
object that is gripped by the robot arm body 100.
[0183] FIGS. 24A to 24B are diagrams illustrating the tool stocker
500c' according to the present embodiment. To simplify the
description, as in the second embodiment, the stocker-inclining
member and other members are omitted in the FIGS. 24A to 24B in the
present embodiment. FIG. 24A is a diagram illustrating the tool
stocker 500c' according to the present embodiment, and FIG. 24B is
a diagram illustrating a state in which the tool stocker 500c'
holds the interchangeable tool 300c'.
[0184] As illustrated in FIG. 24A, the tool stocker 500c' includes
a contact surface 511, a positioning pin 502, tool holding devices
503, and an electrical connection portion 504 of the tool stocker.
Respective tool holding device motors 507 move the tool holding
devices 503 in the directions of arrow J.
[0185] The opening 512, which is similar to that in the first
embodiment, is provided in the contact surface 511, and the
interchangeable tool 300c' is held by the tool stocker 500c' with
the fingers 330c inserted in the opening 512.
[0186] The contact surface 511 is supported by leg portions 506.
Electric wiring 40 is disposed inside a leg portion 506. The
electric wiring 40 connects the electrical connection portion 504
of the tool stocker to the control device 600.
[0187] FIG. 24B is a diagram illustrating the state in which the
tool stocker 500c' holds the interchangeable tool 300c'.
[0188] As illustrated in FIG. 24B, the positioning pin 502 engages
the positioning hole 306. In this state, the tool holding device
motors 507 move the respective tool holding devices 503, which can
position and mount the interchangeable tool 300c' onto the contact
surface 511.
[0189] When the tool stocker 500c' holds the interchangeable tool
300c', the electrical connection portion 504 of the tool stocker is
connected to the electrical connection portion 307. The
interchangeable tool 300c' is thereby connected to the control
device 600 via the wiring 40 that passes through the inside of the
tool stocker 500c', and the interchangeable tool 300c' can receive
electric power from the control device 600 and can transmit and
receive signals to and from the control device 600.
[0190] FIG. 25 is a block diagram illustrating control of the robot
system 10 according to the present embodiment. The control device
600 includes a system control unit 630, a robot arm control unit
640, and a connection path control unit 650.
[0191] The interchangeable tool 300c' has an interchangeable tool
control unit 660 and the tool driving motor 221. The tool stocker
500c' has a tool holding device motor 507. The robot arm body 100
has motors 121 to 126 that drive the respective joints 111 to
116.
[0192] The parts-supplying apparatus 900c has the parts conveyor
unit 901c, the parts locator mechanism 902c, and the sensor 903c.
The parts-supplying apparatus 900c is the same as that used in the
second embodiment.
[0193] In FIG. 25, only a single interchangeable tool control unit
660 is illustrated by way of example. However, a plurality of
interchangeable tool control units 660 having the same
configuration is to be provided for a plurality of interchangeable
tools.
[0194] The system control unit 630 is formed of a computer and has
the CPU 601 that serves as an arithmetic processing unit. The
system control unit 630 also has, as a storage unit, the ROM 602,
the RAM 603, and a hard disk drive (HDD) 604. Moreover, the system
control unit 630 has a storage disk drive 605 and interfaces 612 to
614 of various types.
[0195] The CPU 601 is connected, via a data bus, to the ROM 602,
the RAM 603, the HDD 604, the storage disk drive 605, and the
interfaces 612 to 614. The ROM 602 contains system programs, such
as a basic input output system (BIOS). The RAM 603 is a storage
device that temporarily stores various data, such as results of
arithmetic processing of the CPU 601.
[0196] The HDD 604 is also a storage device that stores various
data such as data obtained externally and results of arithmetic
processing of the CPU 601. The HDD 604 also stores a program 620 to
cause the CPU 601 to perform an arithmetic processing, which will
be described later. The CPU 601 performs steps of a robot control
method in accordance with the program 620 recorded (stored) in the
HDD 604.
[0197] The storage disk drive 605 can read out programs and various
data that are recorded in a storage disk. Note that an external
storage device (not illustrated), such as a rewritable nonvolatile
memory and an external HDD, may be connected to the system control
unit 630.
[0198] The external input device 700, which serves as an
instruction unit, is connected to the interface 612. In accordance
with a user's input, the external input device 700 designates
teaching points to be taught to the robot arm body 100. In other
words, the external input device 700 designates the target joint
angles of the joints J1 to J6 (i.e., the target rotation angles of
motors 121 to 126 of the respective joints 111 to 116). The
teaching point data are output to the HDD 604 via an interface 612
and a data bus.
[0199] The HDD 604 can store the teaching point data designated by
the external input device 700. The CPU 601 can read the teaching
point data recorded (stored) in the HDD 604.
[0200] The system control unit 630 controls the pneumatic apparatus
400 that supplies compressed air to the attachment/detachment
mechanism 250. Pneumatic actuators that are disposed at several
positions in the robot system 10 are connected to the compressed
air source via respective electromagnetic valves 421.
[0201] A pneumatic apparatus control circuit 626 controls
electromagnetic valves 421, pressure sensors 422, and a compressor
423 in response to an instruction from the CPU 601, and thereby
switches between a supply state and a discharge state of the
compressed air that is supplied to the pneumatic actuators. The
pneumatic actuators are the ball plangers that actuate balls 252 of
the attachment/detachment mechanism 250.
[0202] The system control unit 630 also controls the
parts-supplying apparatus 900c. The parts conveyor unit 901c is
connected to a driving circuit 627. The driving circuit 627
supplies electric current to the parts conveyor unit 901c in
response to an instruction from the CPU 601. The parts conveyor
unit 901c is driven so as to convey workpieces Wc.
[0203] The parts locator mechanism 902c is connected to a driving
circuit 628. The driving circuit 628 supplies electric current to
the parts locator mechanism 902c in response to an instruction from
the CPU 601.
[0204] A detection circuit 629 receives a signal relating to
presence/absence of a part from the sensor 903c disposed in the
parts locator mechanism 902c and outputs the signal to the CPU
601.
[0205] These driving circuit 627 to 629 are referred to as the
"parts supply control circuit 910c". Note that the parts supply
control circuit 910c is disposed in the parts-supplying apparatus
900c in the second embodiment, but the parts supply control circuit
910c may be disposed in the control device 600 as in the present
embodiment.
[0206] A driving circuit 631 supplies electric current to the tool
holding device motors 507 in response to an instruction from the
CPU 601. The driving circuit 631 drives the tool holding devices
503 by driving the tool holding device motors 507.
[0207] The robot arm control unit 640 includes a CPU 641, an
electrically erasable programmable read only memory (EEPROM) 642
and a RAM 643 both of which serve as a storage unit, an interface
644, and an arm motor driver 120. These elements are connected to
each other via a data bus.
[0208] The CPU 641 performs arithmetic processing in accordance
with a program 646. The EEPROM 642 is a storage device that stores
the program 646. The RAM 643 is also a storage device that
temporarily stores various data, such as results of the arithmetic
processing of the CPU 641.
[0209] The interface 644 and an interface 613 are connected to each
other via, for example, a cable, through which signals can be
transmitted/received between the system control unit 630 and the
robot arm control unit 640.
[0210] Note that the robot arm control unit 640 is disposed inside
a housing of the control device 600. However, the location of the
robot arm control unit 640 is not limited to the inside of the
housing but may be disposed, for example, inside the robot arm body
100.
[0211] The CPU 601 calculates the moving path of the robot arm body
100 on the basis of the teaching point data and the robot program.
The CPU 601 outputs, to the robot arm control unit 640 at
predetermined time intervals, a signal of angle instruction values
that represent respective rotation angles of the motors 121 to 126
that drive the corresponding joints 111 to 116. The CPU 601 thereby
controls the robot arm body 100 so that the CPU 601 can move the
link 107 disposed at the end of the robot arm body 100 to a desired
location and a desired orientation.
[0212] The connection path control unit 650 includes a CPU 651, an
EEPROM 652 and a RAM 653 both of which serve as a storage unit, and
an interface 654 that is connected to the system control unit 630.
The connection path control unit 650 also includes multiple
interfaces 655 and 656 that are connected to an interchangeable
tool control unit 660. These elements are connected to each other
via a data bus.
[0213] The interface 654 is connected to an interface 614 by, for
example, a cable, through which signals can be transmitted/received
between the system control unit 630 and the connection path control
unit 650. The connection path control unit 650 is disposed inside
the housing of the control device 600. Note that the location of
the connection path control unit 650 is not limited to the inside
of the housing.
[0214] The interchangeable tool control unit 660 is connected to
the system control unit 630 via the connection path control unit
650. The interchangeable tool control unit 660 is disposed in the
interchangeable tool 300c'.
[0215] The interchangeable tool control unit 660 includes a CPU
661, an EEPROM 662 and a RAM 663 both of which serve as a storage
unit, and interfaces 664 and 665, and a driving circuit 667, and
these elements are connected to each other via a data bus.
[0216] The CPU 661 performs arithmetic processing in accordance
with a program. The EEPROM 662 is a storage device that stores the
program. The RAM 663 is also a storage device that temporarily
stores various data such as results of the arithmetic processing of
the CPU 661.
[0217] The driving circuit 667 supplies electric current to the
tool driving motor 221 that drives the fingers 330c in accordance
with an electric current instruction that the driving circuit 667
receives. The tool driving motor 221 drives the fingers 330c by
receiving electric power from the driving circuit 667.
[0218] An interface 664 is connected to an interface 655 when the
electrical connection portion 302 disposed in the interchangeable
tool 300c' is connected to the electrical connection portion 251
disposed in the robot arm body 100.
[0219] The CPU 601 can send an instruction to the interchangeable
tool control unit 660 via the connection path control unit 650
through the wiring 30 disposed inside the robot arm body 100. The
CPU 601 can thereby control the interchangeable tool 300c'.
[0220] An interface 665 is connected to an interface 656 when the
electrical connection portion 307 disposed in the interchangeable
tool 300c' is connected to the electrical connection portion 504
disposed in the tool stocker 500c'.
[0221] The CPU 601 sends an instruction to the interchangeable tool
control unit 660 via the connection path control unit 650 through
the wiring 40 disposed in the tool stocker 500c'. The CPU 601 can
thereby control the fingers 330c of the interchangeable tool
300c'.
[0222] In the present embodiment, the program 620 is stored in the
HDD 604. The HDD 604 is an example of a computer-readable storage
medium. However, the computer-readable storage medium is not
limited to the HDD 604.
[0223] The program 620 may be stored in any suitable storage medium
insofar as the storage medium is computer-readable. For example, a
storage disk illustrated in FIG. 25 or an external storage device
(not illustrated) may be used as a storage medium that supplies the
program 620.
[0224] More specifically, the storage medium that can be used
includes, but not limited to, a flexible disk, a hard disk, an
optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic
tape, a nonvolatile memory, or a ROM.
[0225] Next, a control method of the robot system 10 will be
described. FIG. 26 is a flowchart illustrating a processing flow of
part of a control method of the robot system 10 according to the
present embodiment. FIGS. 27A to 27F are views each of which
illustrates a state corresponding to each step in FIG. 26.
[0226] A flow of processing that the control device 600, especially
the CPU 601 of the control device 600, performs in the robot system
10 will be described below.
[0227] First of all, in step S301, the parts-supplying apparatus
900c is actuated and a workpiece Wc is disposed at a position at
which the interchangeable tool 300c' can grip the workpiece Wc
(FIG. 27A).
[0228] In step S302, the tool stocker 500c' holds the
interchangeable tool 300c' that is attached to the link 107 (FIG.
27B). More specifically, the robot arm body 100 is controlled to
move the interchangeable tool 300c' to a position at which the tool
stocker 500c' can hold the interchangeable tool 300c'.
[0229] Here, the CPU 601 moves the fingers 330c away from each
other by actuating the fingers 330c of the interchangeable tool
300c' before the interchangeable tool 300c' is moved to the
position at which the tool stocker 500c' can hold the
interchangeable tool 300c'.
[0230] After the robot arm body 100 moves the interchangeable tool
300c' to a position at which the tool stocker 500c' can hold the
interchangeable tool 300c', a compressed air that has been supplied
to the attachment/detachment mechanism 250 is discharged so as to
detach the interchangeable tool 300c' from the
attachment/detachment mechanism 250.
[0231] Subsequently, the tool stocker 500c' holds the
interchangeable tool 300c' by actuating the tool holding devices
503 of the tool stocker 500c' (FIG. 27C). In the state in FIG. 27C,
the electrical connection portion 307 of the interchangeable tool
and the electrical connection portion 504 of the tool stocker are
connected to each other.
[0232] In step S303, the CPU 601 instructs the connection path
control unit 650 to switch the connection path for signals and
electric power between the system control unit 630 and the
interchangeable tool control unit 660 to a wiring path routing via
the interface 656 and the interface 665.
[0233] In other words, the interchangeable tool 300c' held by the
tool stocker 500c' receives electric power supplied from the system
control unit 530 and exchanges signals with the system control unit
530 through the wiring 40 that is disposed inside the tool stocker
500c'. This enables the tool stocker 500c' to actuate the fingers
330c.
[0234] In step S304, the workpiece Wc is gripped by moving the
fingers 330c of the interchangeable tool 300c' closer to each other
(FIG. 27D).
[0235] After the workpiece Wc is gripped in the tool stocker 500c',
the CPU 601 instructs the driving circuit 667 to maintain the
gripped state, and the driving circuit 667 thereby maintains the
gripped state by controlling the electric current output to the
tool driving motor 221.
[0236] In step S305, another interchangeable tool is attached to
the robot arm body 100 and the robot arm body 100 performs another
operation.
[0237] When the operation in step S305 is finished, the CPU 601
advances the processing to step S306 and determines whether the
next operation requires the workpiece Wc or not. If NO in step
S306, the operation is finished. If YES in step S306, the
processing proceeds to step S307.
[0238] In step S307, the interchangeable tool 300c' while gripping
the workpiece Wc is attached to the link 107. When attaching the
interchangeable tool 300c' to the link 107, a compressed air is
supplied to the attachment/detachment mechanism 250 so as to couple
the interchangeable tool 300c' to the attachment/detachment
mechanism 250 (FIG. 27E). In the state in FIG. 27E, the electrical
connection portion 302 of the interchangeable tool is connected to
the electrical connection portion 251 of the robot arm.
[0239] In step S308, the CPU 601 instructs the connection path
control unit 650 to switch the connection path for signals and
electric power between the system control unit 630 and the
interchangeable tool control unit 660 to a wiring path routing via
the interface 655 and the interface 664.
[0240] In other words, the interchangeable tool 300c' coupled to
the attachment/detachment mechanism 250 receives electric power
supplied from, and exchanges signals with, the system control unit
630 through the wiring 30 that is disposed inside the robot arm
body 100.
[0241] In step S309, the CPU 601 controls the robot arm body 100
and the interchangeable tool 300c' so as to convey the workpiece Wc
to another location (FIG. 27F), where an operation is performed on
the workpiece Wc that is gripped by the interchangeable tool
300c'.
[0242] As described above, in the robot system 10 according to the
present embodiment, the tool stocker 500c' enables an
interchangeable tool 300c' to grip a workpiece Wc independent of
operation performed by using another interchangeable tool that is
attached to the robot arm body 100.
[0243] Accordingly, the robot arm body 100 can take the
interchangeable tool 300c' that has already gripped the workpiece
Wc. This can save the time required for moving from a position at
which the robot arm body 100 takes an interchangeable tool to a
position at which the interchangeable tool grips a workpiece Wc.
This can also save the time required for gripping the workpiece
Wc.
[0244] As a result, the time required for a series of actions from
changing the interchangeable tools to gripping a workpiece and
operating on the workpiece can be substantially reduced.
[0245] Note that the interchangeable tool 300c' and the tool
stocker 500c' in the third embodiment described above are examples.
The number of the interchangeable tools 300c' and the tool stockers
500c' can be increased in accordance with the shape or orientation
of a workpiece to operate on.
[0246] Also note that in the present embodiment, the tool driving
motor 221 is actuated by using the electrical connection portions
307 and 504 while the interchangeable tool 300c' is held by the
tool stocker 500c'. However, the tool driving motor 221 may be
actuated, for example, by disposing a battery for driving the tool
driving motor 221 in the interchangeable tool 300c' and by using
wireless communication for connecting the control device 600 and
the interchangeable tool control unit 660 to each other.
[0247] With this configuration, an instruction from the control
device 600 can be output in the interchangeable tool control unit
660 via wireless communication, and the tool driving motor 221 can
be actuated by using the battery while the interchangeable tool
300c' is held by the tool stocker 500c'.
MODIFICATION EXAMPLE 1
[0248] Next, modification examples pertaining to the present
embodiment will be described. As described above, the fingers 330
to grip a workpiece We are disposed in the interchangeable tool
300c'. However, in the present modification example, the
interchangeable tool has a tool other than the fingers. A detailed
description will be given below.
[0249] FIGS. 28A to 28B are views schematically illustrating an
interchangeable tool 3000' according to the present modification
example. FIG. 28A is a view illustrating the interchangeable tool
3000' attached to the link 107, and FIG. 28B is a view illustrating
the interchangeable tool 3000' held by a tool stocker 5000'. In
FIGS. 28A to 28B, the major difference compared to the
configuration in the above embodiments is that a screw tightening
tool 360 is provided in place of the fingers 330c.
[0250] As illustrated in FIG. 28A, the screw tightening tool 360,
which is a tool for tightening a small screw, is constituted by a
bit 361 that is shaped like a cylinder and adsorbs and retains a
screw and a motor 362 that rotates the bit 361 around a central
axis 365.
[0251] In addition, a pipe 50 is disposed in the interchangeable
tool 3000' to allow air used to adsorb a screw to pass through. A
fluid connection portion 208 is disposed on the mounting surface of
the link 107 of the robot arm body 100. In addition, fluid
connection portions 309 and 310 are disposed in the interchangeable
tool 3000'.
[0252] The fluid connection portion 208 is connected to an external
vacuum generator or the like, and the interchangeable tool 3000'
can adsorb and retain a screw by producing a vacuum inside the
cylinder of the bit 361.
[0253] When the interchangeable tool 3000' according to the present
modification example is mechanically attached to the link 107, the
electrical connection portion 302 of the interchangeable tool is
connected to the electrical connection portion 251 of the robot
arm, as is the case for the above embodiment.
[0254] Moreover, the link 107 according to the present modification
example has a fluid connection portion 208 of the robot arm. When
the interchangeable tool 3000' and the link 107 are mechanically
coupled to each other, the fluid connection portion 309 of the
interchangeable tool is connected to the fluid connection portion
208 of the robot arm. The interchangeable tool 3000' is thereby in
air communication with the robot arm body 100.
[0255] A compressed air source can supply and discharge compressed
air to and from the interchangeable tool 3000' through the pipe 50
that is disposed inside the robot arm body 100. Note that when the
interchangeable tool 3000' is not attached to the link 107, the
fluid connection portion 309 is isolated from the external
environment.
[0256] FIG. 28B is a view illustrating the state in which the
interchangeable tool 3000' according to the present modification
example is held by the tool stocker 5000'.
[0257] The interchangeable tool 3000', which can be held by the
tool stocker 5000', has the electrical connection portion 307 and a
fluid connection portion 310.
[0258] The tool stocker 5000' according to the present modification
example has the tool holding devices 503 that can fix the
interchangeable tool 3000' as in the above embodiments.
[0259] When the interchangeable tool 3000' is fixed to the tool
stocker 5000', the electrical connection portion 307 is connected
to the electrical connection portion 504 of the tool stocker.
[0260] The interchangeable tool 3000' is thereby connected to the
control device 600 via the wiring 40 that passes through the inside
of the tool stocker 5000', and the interchangeable tool 3000' can
receive electric power from the control device 600 and can transmit
and receive signals to and from the control device 600 via the
wiring 40. The interchangeable tool 3000' can drive the motor 362
while the interchangeable tool 3000' is held by the tool stocker
5000'.
[0261] A fluid connection portion 510 is disposed in the tool
stocker 5000' and is connected to a pipe 60 disposed inside a leg
506.
[0262] The interchangeable tool 3000' is fixed to the tool stocker
5000', and thereby the fluid connection portion 310 of the
interchangeable tool 3000' is connected to the fluid connection
portion 510 of the tool stocker 5000'.
[0263] In the state in which the interchangeable tool 3000' is
fixed to the tool stocker 5000', the compressed air source still
can supply and discharge compressed air to and from the
interchangeable tool 3000' through the pipe 60 that is disposed
inside the tool stocker 5000'.
[0264] However, when the interchangeable tool 3000' is not fixed to
the tool stocker 5000', the fluid connection portion 310 is
isolated from the external environment.
[0265] With this configuration, the interchangeable tool 3000' can
be connected to the electromagnetic valve 421 via the fluid
connection portions 208, 309, 310, and 510. For example, a selector
valve or the like can be used for multiple fluid connection
portions described above.
[0266] A pneumatic apparatus control circuit 626 controls the
electromagnetic valve 421 in response to an instruction from the
CPU 601, and thereby switches between a supply state and a
discharge state of the compressed air that is supplied to the screw
tightening tool 360. The CPU 601 can thereby control the screw
tightening tool 360 adsorbing and retaining a screw.
[0267] In other words, air can be supplied to the interchangeable
tool 3000' from the robot arm body 100 or from the tool stocker
5000', and these two supply modes can be selected suitably.
[0268] Thus, the present embodiment can be applied to such an
interchangeable tool as the screw tightening tool 360 that holds a
component by using an actuator actuated by a fluid, such as
compressed air, as a drive source.
[0269] This can reduce the time required for moving the robot arm
to a parts supply position and the time required for gripping a
part. As a result, the time required for assembling operation of an
assembling apparatus can be substantially reduced.
[0270] Suction for adsorbing a screw is performed via the fluid
connection portions and the pipe 50 or 60 that is disposed in the
robot arm body 100 or in the tool stocker 5000'. This eliminates
the necessity of piping that is disposed directly from the
interchangeable tool 3000' to a compressed air source as is the
case for a known tool for screw tightening.
[0271] When using the interchangeable tool 3000' that is attached
to the robot arm body 100, the piping for screw adsorption can be
disposed inside the robot arm body 100. This eliminates a problem
associated with dragging the piping around and thereby increases
the degree of freedom in positioning interchangeable tools in the
robot system 10.
MODIFICATION EXAMPLE 2
[0272] In the above examples, the fingers 330c of the
interchangeable tool 300c' grip a workpiece. However, instead of
the fingers 330c gripping a workpiece, the fingers 330c may be
adjusted for the gripping position while the interchangeable tool
300c' is held by the tool stocker 500c'. FIG. 29 is a view
illustrating a state in which an adjustment tool 800 is disposed in
place of the parts-supplying apparatus 900c. FIG. 30 is a flowchart
for adjusting the gripping position of the fingers 330c.
[0273] As illustrated in FIG. 29, the adjustment tool 800 is
disposed at a position at which the fingers 330c of the
interchangeable tool 300c' can grip the adjustment tool 800 while
the interchangeable tool 300c' is held by the tool stocker
500c'.
[0274] In step S401 in FIG. 30, the robot arm body 100 causes the
interchangeable tool 300c' to be held by the tool stocker
500c'.
[0275] In step S402, the tool stocker 500c' actuates the fingers
330c of the interchangeable tool 300c' held by the tool stocker
500c' so as to bring the fingers 330c into contact with the
adjustment tool 800.
[0276] In step S403, the control device 600 stores position data of
the fingers 330c that are in contact with the adjustment tool 800.
In step S404, gripping position data for a workpiece is updated
accordingly.
[0277] Even if the gripping position of the fingers 330c deviates
due to the interchangeable tool 300c' deteriorating over time, the
interchangeable tool 300c' can be thereby adjusted every time the
interchangeable tool 300c' is held by the tool stocker 500c'. Thus,
the interchangeable tool 300c' can grip a workpiece properly, which
enables a user to reduce the number of maintenance occasions.
[0278] To be specific, the processing steps of the control flow
described in each of the above embodiments are performed by the
control device 600. Accordingly, the control device 600 can be
configured to perform the processing steps of the control flow in
such a manner that a storage medium storing a control software
program that can perform the above-described functions is provided
to the CPU 601 and the CPU 601 reads out the program stored in the
storage medium and executes the program. In this case, the program
that is read out from the storage medium implements the functions
of each of the above-described embodiments. Accordingly, the
program per se and the storage medium that stores the program
constitute the present disclosure.
[0279] In each of the embodiments, a case in which the ROM 602 or
the RAM 603 serves as the computer-readable storage medium and
stores the program has been described. However, the invention is
not limited to this configuration. The program that realizes the
disclosure may be stored in any suitable storage medium insofar as
the storage medium is computer readable. For example, a HDD, an
external storage device, a storage disk, or the like may be used as
the storage medium that supplies the program.
Other Embodiments
[0280] Embodiment(s) of the present disclosure can also be realized
by a computer of a system or apparatus that reads out and executes
computer executable instructions (e.g., one or more programs)
recorded on a storage medium (which may also be referred to more
fully as a `non-transitory computer-readable storage medium`) to
perform the functions of one or more of the above-described
embodiment(s) and/or that includes one or more circuits (e.g.,
application specific integrated circuit (ASIC)) for performing the
functions of one or more of the above-described embodiment(s), and
by a method performed by the computer of the system or apparatus
by, for example, reading out and executing the computer executable
instructions from the storage medium to perform the functions of
one or more of the above-described embodiment(s) and/or controlling
the one or more circuits to perform the functions of one or more of
the above-described embodiment(s). The computer may comprise one or
more processors (e.g., central processing unit (CPU), micro
processing unit (MPU)) and may include a network of separate
computers or separate processors to read out and execute the
computer executable instructions. The computer executable
instructions may be provided to the computer, for example, from a
network or the storage medium. The storage medium may include, for
example, one or more of a hard disk, a random-access memory (RAM),
a read only memory (ROM), a storage of distributed computing
systems, an optical disk (such as a compact disc (CD), digital
versatile disc (DVD), or Blu-ray Disc (BD).TM.), a flash memory
device, a memory card, and the like.
[0281] In the above embodiments, the ball plangers actuated by air
are used for the attachment/detachment mechanism for the
interchangeable tool and the robot arm body and also used for part
of the positioning mechanism for the interchangeable tool and the
tool stocker. However, the ball plangers may be replaced by devices
using magnetism, such as electromagnets.
[0282] In the above embodiments, the interchangeable tool grips a
target object. However, when the interchangeable tool performs
painting or welding, the fingers may be replaced with other members
suitable for the usage.
[0283] In the first embodiment, the identification sensor 560,
which is a proximity sensor, detects the identification portion 347
and thereby determines the type of interchangeable tool held by the
tool stocker. However, the identification portion 347 may be
replaced by a bar code and the identification sensor 560 may be
replaced by a bar code reader.
[0284] In addition, in the first embodiment, two sensors, in other
words, the presence/absence sensors 570 and the identification
sensor 560, are provided. However, the identification sensor 560
may detect the presence/absence of the interchangeable tool 300 on
the tool stocker 500 without providing the presence/absence sensors
570.
[0285] In the above embodiments, the robot arm body 100 is an
articulated robot that has multiple joints. However, the number of
the joints are not limited to that described in the above
embodiments. In the above embodiments, the robot arm body 100 is a
multiaxial robot arm. However, the configurations described above
can be applied to a robot arm body 100 of different type, such as a
parallel link robot arm.
[0286] The drive sources that drive the joints are not limited to
motors as in the above embodiments. Devices such as artificial
muscles may be adopted as the drive sources.
[0287] The above embodiments are applicable to an apparatus that
can automatically perform actions such as expansion and
contraction, bending and stretching, upward/downward movement,
rightward/leftward movement, turning, or combination of these, on
the basis of the information in the storage of the control
device.
[0288] While the present disclosure has been described with
reference to exemplary embodiments, it is to be understood that the
invention is not limited to the disclosed exemplary embodiments.
The scope of the following claims is to be accorded the broadest
interpretation so as to encompass all such modifications and
equivalent structures and functions.
[0289] This application claims the benefit of Japanese Patent
Application No. 2017-202137 filed on Oct. 18, 2017, No. 2017-202818
filed on Oct. 19, 2017, No. 2017-230993 filed on Nov. 30, 2017, and
No. 2018-097248 filed on May 21, 2018, which are hereby
incorporated by reference herein in their entirety.
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