GB2312414A

GB2312414A - Industrial Robot

Info

Publication number: GB2312414A
Application number: GB9708032A
Authority: GB
Inventors: Hirofumi Tanaka; Nobuhiko Nakaoka; Yasuhiko Hashimoto; Tetsuya Yoshida
Original assignee: Kawasaki Heavy Industries Ltd; Kawasaki Jukogyo KK
Current assignee: Kawasaki Heavy Industries Ltd; Kawasaki Motors Ltd
Priority date: 1996-04-26
Filing date: 1997-04-21
Publication date: 1997-10-29
Also published as: KR100287973B1; KR970069253A; JPH09290391A; JP3327770B2; GB9708032D0

Abstract

An industrial robot comprises a base unit (4), an arm (22) capable of being turned relative to the base unit (4) by a drive motor (M6), and a slide mechanism (30) mounted on the robot arm (22). The slide mechanism (30) has a slide unit (32), a carriage (64) supported on the slide unit (32) so as to be moved linearly by a drive motor (50), and an end effector (60) such as a robot hand supported on the carriage (64). When the carriage (64) is positioned at a front position on the main frame (36), a substantial part of the end effector (60) projects outward from the slide unit (32), so that the principal components of the industrial robot do not interfere with a working machine (88 or 90, Fig 4) when handling a workpiece (84) on the working machine. The main frame is mounted to the arm (22) way along the frame. The carriage is moved by a motor (50) which may be under the control of unit (100) controlling the rest of the robot or a separate control unit. The end effector may be suction heads as shown or washing, painting or welding heads. The robot can be a conventional six or seven axis machine.

Description

INDUSTRIAL ROBOT BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to an industrial robot having a robot arm provided at its front end with a slide mechanism.

Description of the Related Art Industrial robots capable of linearly moving a workpiece are disclosed in, for example, JP-A Nos. 5-76965 and 7-60663. The industrial robot disclosed in JP-A No.

5-76965 comprises a base unit capable of moving on a track extending in a predetermined direction, a robot body mounted on the base unit for turning about a vertical axis, a robot arm supported on the robot body, and a robot hand attached to the robot arm.

The track for such an industrial robot is extended between working machines, such as press machines. When transporting a workpiece from a first to a second working machine, the base unit is located at a first end of the track, the robot hand holds the workpiece positioned at a working position on the first working machine where the workpiece is machined, the industrial robot holding the workpiece by the robot hand is moved from the first end of the track corresponding to the first working machine to the second end of the track corresponding to the second working machine and the robot body is turned through an angle of 1800 during travel from the first end to the second end of the track, the hand releases the workpiece at the second end of the track, and the workpiece is positioned at a working position on the second working machine.

An industrial robot in a first aspect of the invention disclosed in JP-A No. 7-60663 comprises a base unit*, a robot arm supported for turning on the base unit /a robot hand attached for rotation about a verticalaxi to the front end of the robot arm, and a slide mechanism attached to the robot hand. The slide mechanism has a moving means having a base end attached to the robot hand, and a workpiece holder supported on the moving means so as to move from the base end to the front end of the moving means. This robot travels between two working machines to carry a workpiece. When carrying a workpiece machined by a first working machine to a second working machine, a first end of the slide mechanism, i.e., the front end of the sifting means, is located relative to the workpiece disposed in a working region on the first working machine, and the workpiece holder holds the workpiece.

Subsequently, the workpiece holder holding the workpiece is moved to a second end of the slide mechanism, and the robot hand is turned through an angle of lao0 about the axis of turning of the robot hand. Then, the workpiece holder is moved from the second end to the first end of the slide mechanism, and then the workpiece holder releases the workpiece to place the workpiece in a working region on the second working machine.

An industrial robot in a second aspect'of the invention disclosed in JP-A No. 7-60663 has a slide mechanism different from that of the industrial robot in the first aspect of the same invention. The slide mechanism in the second aspect of the invention has a moving means, and a workpiece holder supported on the moving means for movement from a first to a second end of the moving means, and the moving means is attached at its middle portion to a robot hand. When carrying a workpiece from a first working machine to a second working machine, the first end of the slide mechanism is located relative to the workpiece disposed and machined in a working region on the first working machine, the workpiece holder holds the workpiece, the workpiece holder holding the workpiece is moved from a first end to a second end of the slide mechanism, the workpiece holder releases the workpiece to locate the workpiece in a working region on the second working machine.

Those prior art industrial robot, however, have the following problems to be solved. The industrial robot disclosed in JP-A No. 5-76965 needs a relatively large and strong track on which the base unit travels, needs a prime mover having a relatively high output capacity to move the base unit and hence is costly. In the industrial robot in the first aspect of the invention disclosed in JP-A No.

7-60663, it is difficult to expand the moving range of the moving means because the moving means is supported at its base end on the robot hand in a cantilever fashion, and a large inertial load including the slide mechanism and the workpiece needs to be turned when turning the robot hand and thereby the life of the industrial robot is shortened.

In the industrial robot in the second aspect of the invention disclosed in JP-A No. 7-60663, the workpiece holder can be moved only within the moving means between the first and the second end of the moving means.

Therefore, part of the moving means of a relatively high strength is disposed in the working region of the working machine to hold the workpiece and, if the' working machine malfunctions, it is possible that the working machine is damaged by the moving mechanism.

SUMMARY OF THE INVENTION Accordingly, it is a first object of the present invention to provide an industrial robot capable of securing a sufficiently wide moving range for the sliding movement of a workpiece.

A second object of the present invention is to provide an industrial robot suitable for carrying a workpiece between press machines.

A third object of the present invention is to provide an industrial robot having a base unit capable of being disposed substantially at an offset position from a work carrying path between a pair of working machines.

According to the present invention, an industrial robot comprises a base unit, a robot arm capable of being turned relative to the base unit, a first driving means for turning the robot arm, control means for controlling the first driving means, and a slide mechanism mounted on the robot arm. The slide mechanism comprises a slide unit, a carriage capable of being moved between a first end and a second end of the slide unit, a second driving means for driving the carriage for movement, and an end effector such as a workpiece holding means mounted on the carriage. The slide unit is joined at its middle portion to the free end of the robot arm, and most portion or a substantially entire portion of the end effector projects outward from the slide unit when the carriage is positioned at the first end of the slide unit.

Since the middle portion of the slide unit is joined to the robot arm, the slide unit may be relatively long, and the workpiece holding means can be moved in a relatively wide range accordingly. A substantially entire portion of the end effector projects outward from the slide unit when the carriage is positioned at the first end of the slide unit. Therefore, in the case where the end effector is a workpiece holding means, a work piece can be held and released without locating part of the slide unit in a working region on a press machine when the industrial robot is applied to carrying the workpiece from the press machine.

The workpiece holding means may be a robot hand capable of holding a workpiece. The industrial robot provided with the robot hand is suitable for carrying a workpiece from a press machine to another.

The first driving means for turning the robot arm may be a first motor controlled by the control means for operation about a sixth axis, and the second driving means for moving the carriage may be a second motor controlled by the control means for operation about a seventh axis in the case where the robot is a seven-axis robot. Since the first and the second driving means are controlled by the single control means, the carriage of the slide mechanism can be effectively moved while the robot arm is being turned, time necessary for the operation of the industrial robot for a displacement can be reduced, and the moment of inertia of the robot arm can be reduced during the turning of the robot arm. The base unit can be disposed at an offset position from the path between the working machines because the robot arm is controlled for operation about the sixth axis.

The first driving means for turning the robot arm may be a first motor controlled by a first control means for operation about a sixth axis, and the second driving means for moving the carriage may be a second motor controlled by a second control means other than the first control means for controlling the first motor. Since the first and the second driving means are controlled by the separate control means, the slide mechanism can be incorporated as an additional mechanism into a conventional industrial robot, the industrial robot can be manufactured at low cost.

Since the robot arm is controlled for operation about the sixth axis, the base unit can be disposed at an offset position from the path between the working machines.

The above and other objects, features and advantages of the present invention will become more apparent from the following description taken in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic side view of an industrial robot in a preferred embodiment according to the present invention; Fig. 2 is a sectional view of a slide mechanism included in the industrial robot of Fig. 1; Fig. 3 is a sectional view taken on line III-III in Fig. 2, and Fig. 4 is a schematic plan view of assistance in explaining the operation of the industrial robot of Fig. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to Fig. 1, an industrial robot in a preferred embodiment according to the present invention has a base unit 4 installed on the floor 2. A first robot arm 6 is supported for turning on the base unit 4, and a second robot arm 8 is connected to the first robot arm 6. A flange 10 is attached to the front end of the second robot arm 8, and a tool support mechanism 12 is connected to the flange 10. The base unit 4 is turned about a vertical first axis 14 to a desired angular position by a first drive motor M1. The first robot arm 6 can be turned about a horizontal axis 16, i.e., an axis perpendicular to the paper, to a desired angular position by a second drive motor M2. The second robot arm 8 is turned about a third axis 18, i.e., an axis perpendicular to the paper, to a desired angular position by a third drive motor M3.

The tool support mechanism 12 has'a third robot arm 20 and a fourth robot arm 22 connected to the third robot arm 20. The third robot arm 20 is joined for turning about a fourth axis 24 coinciding with the axis of the second robot arm 8, i.e., a horizontal axis as viewed in Fig. 1, to the second robot arm 8 and is turned to a desired angular position by a fourth drive motor M4. The fourth robot arm 22 is pivotally joined for turning about a fifth axis 26, i.e., a horizontal axis perpendicular to the paper as viewed in Fig. 1, to the third robot arm 20 and is turned to a desired angular position by a fifth motor M5.

A slide mechanism 30 is attached to the extremity of the fourth arm 22. The slide mechanism 30 has a slide unit 32 joined for turning about a sixth axis 34, i.e., a vertical axis as viewed in Fig. 1, to the fourth arm 22 and is turned to a desired angular position by a sixth motor M6.

Referring to Figs. 2 and 3 in connection with Fig. 1, slide unit 32 has a main frame 36 attached to the fourth arm 22. Support plates 38 and 40 respectively supporting bearings 42 and 44 are attached to the opposite ends of the main frame 36, respectively. A drive shaft 46 is supported for rotation in the bearings 42 and 44. The drive shaft 46 is a rod provided in its circumference with male screw threads. A protective cover 48 is attached to one end of the main frame 36, and a drive motor 50 is mounted on the other end of the main frame 36. A timing-belt pulley 52 is mounted on the output shaft of the drive motor 50, a timing-belt pulley 54 is mounted on one end of the drive shaft 46 projecting from the support plate 38, and a timing belt 56 is extended between the timing-belt pulleys 54 and 56 to transmit the driving force of the drive motor 50 to the drive shaft 46. A protective cover 58 is attached to the drive motor 50 so as to cover the timing-belt pulleys 52 and 54 and the timing belt 56. The output shaft of the drive motor 50 may be coupled directly with the drive shaft 46 to transmit the driving force of the drive motor 50 to the drive shaft 46.

A pair of support members 62 each provided with a threaded hole are mounted on the drive shaft 46 with a predetermined axial space therebetween, and a carriage 64 having a cuboidal shape is attached to the support members 62. A pair of projections 64A and 64B project upward from the opposite sides of the carriage 64, a pair of guide rails 65 and 67 are attached to the main frame 36 so as to correspond to the projections 64A and 64B, respectively.

The guide rails 65 and 67 are extended in parallel to the drive shaft 46 between the opposite longitudinal ends of the main frame 36.

When the output shaft of the drive motor 50 is driven for rotation in a predetermined normal direction or in a reverse direction opposite the normal direction, the drive shaft 46 is rotated trough the timing-belt pulley 52, the timing belt 56 and the timing-belt pulley 54, so that the carriage 64 is moved together with the pair of support members 62 to the right or to the left as viewed in Figs.

1 and 2. Thus, the carriage 64 can be moved between a front position indicated by alternate long and two short dashes line in Fig. 1 (a position corresponding to a first end of the slide unit 32) and a back position indicated by continuous line in Fig. 1 (a position corresponding to a second end of the slide unit 32). The carriage 64 moves linearly along the drive shaft 46 between the front position and the back position and is guided by the guide rails 65 and 67 during movement. The carriage 64 is positioned at a desired position on the basis of signals provided by an origin detector for detecting the origin of the carriage 64, and an encoder built in the drive motor 50. The drive shaft 46 and the support members 62 may form a ball-screw mechanism.

Since a longitudinally middle portion of the main frame 36 is joined to the free end of the fourth robot arm 22 as shown in Fig. 1, the carriage 64 is moved substantially equal distances respectively to the right and to the left from the middle of the main frame 36; that is, a first distance between a middle position corresponding to the middle portion of the main frame 36 joined to the fourth robot arm 22 and the first end of the main frame 36 and a second distance between the middle position and the second end of the main frame 36 are substantially equal to each other and hence the ratio between the first distance and the second distance is substantially 1:1. The ratio between the first and the second distance may be other than 1:1, for example, 3:7, if a condition so requires, the condition including a range in which a workpiece 84 (Fig.

4) is moved and the moment of inertia of a system including the workpiece 84 and a workpiece holding device or an end effector 60. The workpiece holding end effector 60 is supported on the carriage 64. In this embodiment, a tool changer 66 is attached to the lower surface of the carriage 64, and the workpiece holding end effector 60 is supported on the tool changer 66. If the workpiece holding end effector 60 is changed only once in a long while, the tool changer 66 may be omitted.

The workpiece holding device or end effector 60 has a robot hand 68 for holding a workpiece. The robot hand 68 has a mount 70 extending perpendicularly to the paper as viewed in Figs. 1 and 2, and three suction pipes 72 extend in parallel spaced relation from the mount 70 perpendicularly to the length of the mount 70, as shown in Fig. 4. Suction members 74, such as suction cups, are attached to a middle portion and an end portion, respectively of each suction pipe 72. Tubes 76 (only one of the tubes 76 is shown in Fig. 1) each have one end connected to the base ends of the suction pipes 72 and the other end connected to a connecting member 78 (Fig. 1) attached to the main frame 36. The connecting member 78 is connected through a valve 82 attached to a base portion of the second robot arm 8 to a suction device P, such as a vacuum pump. In a state where the suction device P is activated, an attractive force produced by the suction device P acts through the tubes 80 and 76, the suction pipes 72 and the suction member 74 on the workpiece 84 to attract and hold the workpiece 84 by the suction members 74 if the valve 82 is opened. If the valve 82 is closed, the attractive force is removed from the workpiece 84 and the suction members 74 release the workpiece 84. Although the three suction pipes 72 are attached to the'mount 70 in this embodiment, any suitable number of suction pipes, for example, one, two or more than four suction pipes, may be attached to the mount 70, provided that the workpiece 84 can properly be held. Each suction pipe 72 may be provided with one or more than three suction members instead of the two suction members 74.

The operations of the drive motor M1 for turning the base unit 4, the drive motors M2 to M5 for driving the robot arms 6, 8, 20 and 22, the drive motor M6 for turning the main frame 36, and the drive motor 50 of the slide mechanism 30 are controlled by a control unit 100. As is readily understood, the drive motors M1 to M5 are controlled by the control unit 100 for turning the associated components about the first to the fifth axis, the drive motor M6 is controlled by the control unit 100 for turning the slide mechanism 30 about the sixth axis, and the drive motor 50 is controlled by the control unit 100 for moving the carriage 64 along a seventh axis. The operations of the components of the industrial robot including the slide mechanism 30 about the six axes and along the seventh axis can be controlled according to a conventional seven-axis control program.

The operation of the industrial robot will be described mainly with reference to Figs. 1 and 4. The industrial robot is disposed between a first working machine 88 disposed on the left side as viewed in Fig. 4, and a second working machine 90 disposed on the right side as viewed in Fig. 4. In this case, the working machines 88 and 90 are supposed to be press machines, and the workpiece 84 is a plate to be subjected to press working on the press machines. When transferring the workpiece 84 from the first working machine 88 to the second working machine 90, the industrial robot is set in a position indicated by continuous lines in Fig. 4, in which the drive motor M6 is actuated to turn the main frame 36 relative to the second robot arm 8 counterclockwise, i.e., in the direction of the arrow 95, through a predetermined angle; and the drive motor 50 is actuated to move the carriage 64 in the direction of the arrow 93 (Fig. 1) to the front end of the main frame 36.

As shown in Figs. 1 and 4, when the carriage 64 is positioned at the front end of the main frame 36, most part or a substantially whole part of the workpiece holding end effector 60, i.e., most part of the suction pipes 72, extends outside the main frame 36 and the suction members 74 are located above the plate-shaped workpiece 84 placed in the working region of the first working machine 88. In this state, the members having a relatively high strength, i.e., the main frame 36, the base member and so on, are kept outside the working region of the working machine 88, and only the suction pipes 72 and the suction members 74 having a relatively low strength are placed above the working region. Therefore, the working force of the working machine 88 is exerted on only the suction pipes 72 and the suction members 74 if the working machine 88 operates erroneously. Accordingly, the components of the working machine 88, such as dies for working the workpiece 84, are not damaged.

Thereafter, the control unit controls the industrial robot to move the slide mechanism 30 toward the workpiece 84 as far as the suction members 74 are brought into contact with the upper surface of the workpiece 84, and then the valve 82 is opened. Consequently, the attractive force of the suction device P acts on the workpiece 84, and the workpiece 84 is held on the workpiece holding end effector 60 by suction. After the workpiece 84 has thus been held on the workpiece holding end effector 60, the slide mechanism 30 is raised slightly, the drive motor 50 is actuated to rotate the screw shaft 46 in the reverse direction to move the carriage 64 from the front position in the direction of the arrow 94 (Fig. 1) to the back position on the main frame 36. The workpiece holding end effector 60, the suction pipes 72 and the workpiece 84 in this second state are indicated at 60A, 72A and 84A, respectively. When the carriage 64 is positioned at the back position, most part of the suction pipes 72 are positioned under the main frame 36 and only a small length of the suction pipes 72 projects outside from the main frame 36. Since the workpiece holding end effector 60 is thus retracted, the collision of the workpiece holding end effector 60 and the workpiece 84 held on the effector 60 with the components of the working machine 88, such as columns, can be avoided during the turning of the workpiece holding end effector 60.

Subsequently, the base unit 4 is turned clockwise, i.e., in the direction of the arrow 96 in Fig. 4, to change the state of the robot via a third state to a fourth state.

In the third state, the workpiece holding end effector 60 is at the substantially middle between the working machines 88 and 90. In the fourth state, the workpiece holding end effector 60 is at a position to transfer the workpiece 84 to the second working machine 90. The main frame 36, the workpiece holding end effector 60, the suction pipes 72 and the workpiece 84 in the third state are indicated at 36B, 60B, 72B and 84B, respectively. The main frame 36, the workpiece holding end effector 60, the suction pipes 72 and the workpiece 84 in the fourth state are indicated at 36C, 60C, 72C and 84C, respectively. As is obvious from Fig. 4, the carriage 64, the workpiece holding end effector 60 and the workpiece 84 are held near the first axis 14 corresponding to the axis of turning of the base unit 4, and the workpiece holding end effector 60 and the workpiece 84 are held near the sixth axis 34 because the carriage 64 is held at the back position. Therefore, the moment of inertia of a system including the workpiece holding end effector 60, the carriage 64 and the workpiece 84 is relatively small and, the robot arms 6, 8, 20 and 22, the workpiece holding end effector 60 and the workpiece 84 are not loaded greatly during the turning motion of the industrial robot. Therefore, robot can be operated at high acceleration and high deceleration. During the turning motion of the robot from the position in the second state to the position in the fourth state, the drive motors M1 to M6 are controlled simultaneously by the control unit 100.

Therefore, the slide mechanism 30 can be turned while the base unit 4 is being turned, so that time necessary to position the workpiece holding end effector 60 at a desired position can be reduced. Naturally, the base unit 4 and the slide mechanism 30 may sequentially be turned.

In this embodiment, the base unit 4 and the slide mechanism 30 are turned after the carriage 64 has been positioned at the back position. However, the turning of the slide mechanism 30 and the base unit 4 may be started while the carriage 64 is approaching the back position or the turning of the base unit 4 may be started after the turning of the slide mechanism 30 has been started.

After the industrial robot has been set in the fourth state, the drive motor 50 is actuated to move the carriage 64 in the direction of the arrow 93 (Fig. 1) to the front position on the slide unit 32 to set the industrial robot in a fifth state. The workpiece holding end effector 60, the suction pipes 72 and the workpiece 84 in the fifth state are indicated at, 60D, 72D and 84D, respectively.

When the carriage 64 is positioned at the front position, most part of the workpiece holding end effector 60 projects outside the main frame 36 and the workpiece 84 held by the suction members 74 is located above a working region on the second working machine 90. In the fifth state, the main frame 36 and the base member 70 are outside the working region on the second working machine 90, and only the suction pipes 72 and the suction members 74 having a relatively low strength are placed above the working region. Therefore, the working force of the working machine 90 is exerted on only the suction pipes 72 and the suction members 74 if the working machine 90 operates erroneously. Accordingly, the components of the working machine 90, such as dies for working the workpiece 84, are not damaged.

Then, the control unit 100 controls the industrial robot to lower the slide mechanism 30 toward the working region so that the workpiece 84 held by the suction members 74 is located in the working region on the second working machine 90. Subsequently, the valve 82 is closed to release the workpiece 84 from the suction members 74 so that the workpiece 84 is placed in the working region.

The industrial robot reverses the foregoing steps of operation and repeats the foregoing workpiece transfer cycle to transfer a workpiece 84 from the working region on the first working machine 88 to the working region on the second working machine 90. The second working machine 90 carries out a predetermined processing operation to process the workpiece 84 placed in the working region on the second working machine 90.

As shown in Fig. 4, the fourth robot arm 22 to which the slide unit mechanism 30 is joined is controlled for turning about the sixth axis 34, and most part of the workpiece holding end effector 60 can be projected from the main frame 36. Therefore, the base unit 4 of the industrial robot need not be disposed in an intermediate region interconnecting the working regions on the working machines 88 and 90 and may be disposed at an offset region from the intermediate region. Therefore, as will be understood from Fig. 4, the workpiece 84 can be carried from the first working machine 88 to the second working machine 90 by turning the base unit 4 through a relatively small angle in a relatively short time. Since the middle portion of the main frame 36 is joined to the fourth robot arm 22, the carriage 64 can be moved in an enlarged range.

Although the drive motor 50 of the slide mechanism 30 is controlled by the control unit 100 which controls the drive motors M1 to M6 of the industrial robot in this embodiment, the drive motor 50 may be controlled by another control unit. If the drive motor 50 is controlled individually, the slide mechanism 30 can be attached to the fourth robot arm 22 of a standard industrial robot to provide an inexpensive industrial robot with slide mechanism.

The industrial robot provided with the slide mechanism 30 supporting the workpiece holding end effector 60 which moves linearly in a wide range is suitable for use for transferring a workpiece from one to the other of the working machines, such as press machines. The workpiece holding end effector 60 supported on the slide mechanism 30 can be replaced with another end effector to use the industrial robot as a washing robot for washing parts and the like, a welding robot for welding two members or a painting robot for paining parts. When the industrial robot is used as a washing robot, a welding robot or a painting robot, an end effector, such as a washing nozzle, is supported so that most part of the end effector projects from the main frame of the slide mechanism when the carriage is at the front position on the main frame.

Therefore, the end effector is separated by a relatively great distance from the base unit during operation, and hence the contamination of the industrial robot with a washing liquid or the like can be prevented.

The slide mechanism can be incorporated into industrial robots of various types, such as a wall-mounted industrial robot and traveling industrial robot which travels along a track. The slide mechanism can be incorporated also into five-axis, four-axis and three-axis industrial articulated robots.

As is apparent from the foregoing description, according to the present invention, the middle portion of the slide unit is joined to the robot arm, and hence the slide unit may be relatively long, and the workpiece holding means can be moved in a relatively wide range accordingly. Most portion of the workpiece holding means projects outward from the slide unit when the carriage is positioned at the front end of the slide unit. Therefore, a work piece can be held and released without locating part of the slide unit in a working region on a working machine, such as a press machine, when the industrial robot is used for carrying the workpiece from the working machine to another working machine.

Since the end effector is a robot hand capable of holding a workpiece, the industrial robot is suitable for use in carrying a workpiece from a may be controlled by a first control means, and the second driving means for moving the carriage may be controlled by a second control means, the slide mechanism can be incorporated as an additional mechanism into a conventional industrial robot. Thus, an inexpensive industrial robot is provided. Since the robot arm is controlled for operation about the sixth axis, the base unit can be disposed at an offset position from the path between the working machines.

Although the invention has been described in its preferred form with a certain degree of particularity, obviously many changes and variations are possible therein.

It is therefore to be understood that the present invention may be practiced otherwise than as specifically described herein without departing from the scope and spirit thereof.

Claims

What is claimed is:

1. An industrial robot comprising: a base unit; a robot arm capable of being turned relative to the base unit; a first driving means for driving the robot arm for turning; control means for controlling the first driving means; and a slide mechanism mounted on the robot arm; wherein the slide mechanism comprises a main frame, a movable member capable of being moved between a first position at one end and a second position at another end of the main frame; a second driving means for moving the movable member, and an end effector mounted on the movable member, a middle portion of the main frame is joined to a free end of the robot arm, and said end effector is provided such that a substantial portion of the end effector will project outward from the main frame of the slide mechanism when the movable member is positioned at the front position on the main frame of the slide mechanism.

2. The industrial robot according to claim 1, wherein said robot is a seven-axis robot, and wherein the first driving means is a first motor controlled by the control means for operation to drive the associated component for turning about a sixth axis, and the second driving means is a second motor controlled by the control means for operation to drive the associated component for turning about a seventh axis.

3. The industrial robot according to claim 1, wherein said robot is a seven-axis robot, and wherein the first driving means is a first motor controlled by the control means for operation to drive the associated component for turning about a sixth axis, and the second driving means is a second motor controlled by another control means.

4. The industrial robot according to claim 1, wherein the end effector is a robot hand for holding a workpiece.

5. The industrial robot according to claim 1, wherein the end effector is a washing head.

6. The industrial robot according to claim 1, wherein the end effector is a welding head.

7. The industrial robot according to claim 1, wherein the end effector is a painting head.

8. An industrial robot substantially as described herein with reference to and as illustrated in the accompanying drawings.