JP5874291B2 - Tool center point setting method for articulated robot and jig mounting structure for tool center point setting - Google Patents

Description

  The present invention relates to a tool center point setting method for an articulated robot and a tool for setting a tool coordinate system for a tool attached to a wrist axis flange based on a flange coordinate system set for a wrist axis flange of an articulated robot. The present invention relates to a jig mounting structure for setting a center point.

  For articulated robots (eg 6-axis articulated robots) used for industrial robots, various tools (eg suction pads, open / close hands, etc.) are generally attached to the wrist shaft flange at the tip of the robot arm. It is versatile enough to handle various tasks. It is unclear at the time of shipment of the robot what kind of tool can be attached. At the time of shipment, the coordinate system (flange coordinate system: XFLANGE, YFLANGE, ZFLANGE) is used to specify the movement of the wrist axis tip of the robot. ) Is set.

  However, after attaching the tool to the wrist axis flange, it is inconvenient to move the tool in the flange coordinate system of the wrist axis flange, and a new coordinate system based on the tool (tool coordinate system: XTOOL, YTOOL, ZTOOL) Is set. In this setting, a standard jig installed on the floor where the articulated robot is installed is mounted on the wrist shaft flange by attaching a dedicated jig instead of the tool and operating the articulated robot. It was done by moving to the reference point of the jig. In this way, the task of setting the tool coordinate system for the tool attached to the wrist axis flange based on the flange coordinate system set for the wrist axis flange of the articulated robot is referred to as the tool center point (hereinafter referred to as TCP (Tool Center It is also called “Point”).

  In addition, although what was described in patent documents 1-3 is known as invention regarding the calibration of an industrial robot, these are wrist axes based on the flange coordinate system set to the wrist axis flange of an articulated robot. It does not set the tool coordinate system for the tool attached to the flange.

JP-A-8-155866 JP 2003-181782 A JP 2011-67889 A

  By the way, in the conventional TCP setting work, the tools (suction pad, opening / closing hand, etc.) attached to the wrist shaft flange of the articulated robot are once removed from the wrist shaft flange, and instead, a dedicated jig for TCP setting is used as the wrist shaft flange. It was attached to.

  For this reason, in order to perform the work using the tool after the TCP setting work is completed, it is necessary to remove the dedicated jig from the wrist shaft flange and attach a tool (suction pad, opening / closing hand, etc.) to the wrist shaft flange. Such exchange (setup change) takes time and effort and is inefficient. Further, if a slight shift occurs in the mounting position when the tool is attached to or detached from the wrist shaft flange, the accuracy of work by the tool is deteriorated.

  The object of the present invention created in view of the above circumstances is that an articulated robot that can quickly perform a work with a tool after a TCP setting work and that does not cause a deviation in the mounting position of the tool on the wrist shaft flange. The object is to provide a TCP setting method and a mounting structure for a TCP setting jig.

According to the present invention created to achieve the above object, a tool coordinate system for a tool attached to a wrist axis flange is set based on a flange coordinate system set for a wrist axis flange of an articulated robot. A tool center point setting method, in which a suction pad that holds and holds a workpiece as a tool is attached to the wrist shaft flange, and a jig is attached to the suction pad so as to cover the workpiece contact portion. Tool center point setting that sets the tool coordinate system based on the flange coordinate system by moving the jig to the pointed reference point of the reference jig installed on the floor where the articulated robot is installed. Provided is a tool center point setting method for an articulated robot characterized in that the work is performed and the jig is removed from the suction pad .

Further, according to the present invention, the jig mounting structure used when setting the tool coordinate system for the tool attached to the wrist shaft flange based on the flange coordinate system set for the wrist shaft flange of the articulated robot. The tool includes a tool attached to the wrist shaft flange of the articulated robot and a jig attached to the tool. The jig operates the floor of the articulated robot by operating the articulated robot. The tool is moved to a sharp reference point of the reference jig installed on the surface, the tool is a suction pad that sucks and holds the workpiece, and the jig covers the workpiece contact part of the suction pad, is detachably attached to the suction pad, without removing the suction pad mounted on the wrist axis flange from the wrist axis flange, articulated robot which jig is characterized in that it is detachably attached to the suction pad Mounting structure of a jig for tool center point setting is provided in.

  According to the present invention, the tool for TCP setting is attached to the tool without removing the tool from the wrist shaft flange of the articulated robot, the TCP setting work is performed, and the jig is removed from the tool after the work is completed. I am doing so. Thus, since the TCP setting work is performed without removing the tool from the wrist shaft flange, the multi-joint robot can be actuated promptly after the work is completed, and the work with the tool can be performed. In addition, since the tool remains fixed to the wrist shaft flange, even if the TCP setting operation is performed, the mounting position of the tool on the wrist shaft flange is unlikely to occur.

It is a perspective view which shows the articulated robot with which this invention is applied, a flange coordinate system, and a tool coordinate system. It is a perspective view which shows a part of TCP setting operation | work of the articulated robot used as the premise of this invention, (a) is a 1st process, (b) is a 2nd process, (c) is a 3rd process, (d). Indicates the fourth step. It is explanatory drawing of the suction pad as a tool with which a wrist axis | shaft flange of an articulated robot is mounted | worn, (a) is a sectional side view of a suction pad, (b) is a bottom view of a suction pad. It is explanatory drawing which shows a mode that the jig | tool for TCP setting which concerns on 1st Embodiment of this invention was mounted | worn to the suction pad, (a) is a sectional side view of a suction pad and a jig | tool, (b) is (a). FIG. It is explanatory drawing of the opening / closing hand as a tool with which the wrist axis flange of an articulated robot is attached, (a) is a top view of an opening / closing hand, (b) is a front view of an opening / closing hand, (c) is a side view of an opening / closing hand. FIG. It is explanatory drawing which shows the jig | tool for TCP setting which concerns on 2nd Embodiment of this invention (the jig | tool hold | gripped and released by an opening-and-closing hand), (a) is a top view of a jig | tool, (b) is (a ) Is a cross-sectional view taken along the line b-b of FIG.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

(Articulated robot)
An articulated robot to which an embodiment of the present invention is applied will be described. As shown in FIG. 1, this articulated robot (for example, a 6-axis articulated robot) 1 is used for an industrial robot or the like. Various tools (for example, suction pads, open / close hands, etc.) can be attached, and they are versatile enough to handle various tasks. Since what kind of tool is attached is unknown at the time of shipment of the robot 1, at the time of shipment, in order to define the movement of the tip of the wrist axis of the robot 1, a coordinate system (flange coordinate system: XF, YF, ZF) are set.

  Since it is inconvenient to move the tool in the flange coordinate system of the wrist shaft flange 2 after attaching the tool to the wrist shaft flange 2, a new coordinate system based on the tool (tool coordinate system: XT, YT, ZT) ) Is set. That is, based on the flange coordinate system set for the wrist shaft flange 2 of the multi-joint robot 1, an operation for setting the tool coordinate system for the tool attached to the wrist shaft flange 2 is performed. This operation is called a tool center point setting operation (TCP setting operation). Hereinafter, the TCP setting operation will be briefly described.

(TCP setting work)
A part of the TCP setting work which is the premise of the present invention will be briefly described. Before starting the work, as shown in FIG. 1, a dedicated jig 3 for TCP setting is attached to the wrist shaft flange 2 of the articulated robot 1, and as shown in FIGS. 2 (a) to 2 (d), The reference jig 4 is placed (placed) on the floor where the multi-joint robot 1 is installed, in a range where the dedicated jig 3 can reach. As the reference jig 4, for example, a column having a reference point 4 a pointed at the top is used.

  The articulated robot 1 is operated to move the tip 3a of the dedicated jig 3 to the reference point 4a of the reference jig 4 in four or more postures. Here, four postures will be described as an example. The articulated robot 1 is operated to move the tip 3a of the dedicated jig 3 to the reference point 4a of the reference jig 4 as shown in FIG. As shown in FIG. 2B, the tip 3 a of the dedicated jig 3 is moved to the reference point 4 a of the reference jig 4 from a direction different from that in FIG. As shown in FIG. 2C, the tip 3 a of the dedicated jig 3 is moved to the reference point 4 a of the reference jig 4 from a direction different from that in FIGS. 2A and 2B. Finally, as shown in FIG. 2 (d), the tip 3a of the dedicated jig 3 is moved down vertically from the reference point 4a and moved to the reference point 4a. The operation data of the articulated robot 1 in FIGS. 2 (a) to 2 (d) is saved. Thereby, the origin of the tool coordinate system can be determined.

  By the way, when the TCP setting dedicated jig 3 is attached to the wrist shaft flange 2 of the articulated robot 1 instead of the tool as described above, the tool 3 is used to perform the work with the tool after the TCP setting work is completed. The tool must be attached to the wrist shaft flange 2 after being detached from the wrist shaft flange 2, and it takes time and effort to change the setup, resulting in poor efficiency. Further, if a deviation occurs when the tool is attached to or detached from the wrist shaft flange 2, there arises a problem that the working accuracy of the tool is lowered.

  Therefore, in the present invention, as described above with reference to FIGS. 1 and 2, when performing the TCP setting operation of the articulated robot 1, the dedicated jig 3 for TCP setting is applied to the wrist shaft flange 2 of the articulated robot 1. A tool (suction pad, opening / closing hand, etc.) actually used for work is attached to the wrist shaft flange 2 and a TCP setting jig is detachably attached to the tool. Hereinafter, this point will be described in detail.

(First embodiment)
As a first embodiment of the present invention, a description will be given of a tool 5 having a suction pad 6 shown in FIG. 3 and a TCP setting jig 7 shown in FIG.

(Suction pad as a tool)
FIG. 3 shows a suction pad 6 mounted as a tool 5 on the wrist shaft flange 2 of the articulated robot (6-axis articulated robot) 1 shown in FIG. FIG. 3A is a side sectional view of the suction pad 6, and FIG. 3B is a bottom view of the suction pad 6.

  The suction pad 6 is attached to the empty wrist shaft flange 2 by removing the above-described dedicated jig 3 for setting the TCP from the wrist shaft flange 2 of the articulated robot 1 shown in FIG. The suction pad 6 includes a base 61 attached to the wrist shaft flange 2 and a pad main body 62 provided on the base 61. The base 61 is made of a metal plate, and a vacuum passage 63 communicating with a vacuum device (not shown) provided on the wrist shaft flange 2 of the articulated robot 1 is formed through the base 61. Yes. The pad main body 62 is formed in a bellows shape or a bellows shape from a flexible material such as rubber, and an internal passage 64 communicating with the vacuum passage 63 of the base 61 is formed in the pad main body 62. Yes.

  According to this suction pad 6, the work (not shown) is sucked and held on the work abutting portion 65 of the pad main body 62 by operating the vacuum device provided on the wrist shaft flange 2 and sucking air from the vacuum passage 63. The work can be released from the pad main body 62 by stopping the vacuum device or blowing air from the vacuum passage 63. Therefore, by operating the articulated robot 1 shown in FIG. 1 to which the suction pad 6 is attached, the work held by the pad main body 62 can be moved to a desired position in a desired posture, and the work can be moved to a desired posture / location. Can be released from the pad main body 62.

(Jig for TCP setting)
FIG. 4 shows a TCP setting jig 7 attached to the suction pad 6. FIG. 4A is a side sectional view of the jig 7 attached to the suction pad 6, and FIG. 4B is a bottom view of the jig 7.

  The jig 7 is extended toward the base 61 of the suction pad 6 from the flange 72 formed so as to cover the reference pin 71 having a sharp tip, the workpiece 72 of the suction pad 6 and the workpiece contact portion 65. Rod 73 and a mounting portion 74 that is detachably attached to the base 61 of the suction pad 6, and the reference pin 71, flange 72, rod 73, and mounting portion 74 are integrally formed of metal or the like. .

  The tip of the reference pin 71 is aligned with the reference point 4a of the reference jig 4 placed on the floor surface by operating the articulated robot 1 in the TCP setting operation shown in FIG. The flange 72 covers the work contact portion 65 of the pad main body 62 to protect the work contact portion 65 from being damaged. As will be described later, an engaging portion 72a with which a spanner is engaged is cut out in parallel to the flange 72 so that the male screw portion 74a of the mounting portion 74 is screwed into the female screw portion 63a of the vacuum passage 63. .

  The attachment portion 74 of the jig 7 has a male screw portion 74 a provided at the tip of the rod 73 and a stopper flange 74 b provided on the rod 73. The male screw portion 74 a is screwed into a female screw portion 63 a formed on the inner peripheral surface of the vacuum passage 63. The stopper flange 74b is pressed against the opening edge of the vacuum passage 63 when the male screw portion 74a is screwed into the female screw portion 63a, and determines the screwing position by regulating the screwing depth of the male screw portion 74a. The vacuum passage 63 is disposed at the center (pad center) of the internal passage 64 of the pad body 62 so that the jig 7 is attached to the pad center of the suction pad 6.

(TCP setting method)
As described above, the TCP setting is attached to the wrist shaft flange 2 based on the flange coordinate system (XF, YF, ZF) set to the wrist shaft flange 2 of the articulated robot 1 shown in FIG. This means setting the tool coordinate system (XT, YT, ZT) on the tool 5 (suction pad 6).

  In the TCP setting method according to the present embodiment, first, the tool 5 (suction pad 6) is attached to the wrist shaft flange 2 with a bolt nut or the like, and the female screw part 63a formed in the vacuum passage 63 of the suction pad 6 is attached to the wrist shaft flange 2. The male threaded portion 74 a of the TCP setting jig 7 is screwed and the jig 7 is attached to the suction pad 6. Here, the screwing depth of the male screw portion 74 a to the female screw portion 63 a is set until the stopper flange 74 b of the jig 7 is pressed against the opening edge of the vacuum passage 63, so that the mounting position of the jig 7 is changed. Accurately determined.

  Next, the articulated robot 1 is operated, and the tip 71a of the reference pin 71 of the jig 7 is moved to the reference point 4a of the reference jig 4 as shown in FIG. 2, and as already described with reference to FIG. Perform TCP setting work. Thereafter, the male screw part 74a is loosened and removed from the female screw part 63a, whereby the jig 7 is removed from the suction pad 6, and the work suction operation is performed with the suction pad 6 from which the jig 7 has been removed.

(Action / Effect)
According to this embodiment, without removing the tool 5 (suction pad 6) from the wrist shaft flange 2 of the articulated robot 1, the tool 5 is attached to the jig 7 for performing TCP setting and the TCP setting work is performed. After the work is finished, the jig 7 is removed from the tool 5. Thus, since the TCP setting work is performed without removing the tool 5 from the wrist shaft flange 2, the multi-joint robot 1 is actuated promptly after the work is finished (work suction work by the suction pad 6). )It can be performed. In addition, since the tool 5 remains fixed to the wrist shaft flange 2, even if the TCP setting operation is performed, the mounting position of the tool 5 on the wrist shaft flange 2 is unlikely to occur.

(Second Embodiment)
Next, as a second embodiment of the present invention, a tool 5 using an opening / closing hand 8 shown in FIG. 5 and a TCP setting jig 9 shown in FIG. To do.

(Opening and closing hand as a tool)
An open / close hand 8 attached as a tool 5 to the wrist shaft flange 2 of the articulated robot 1 shown in FIG. 1 is shown in FIG. 5A is a plan view of the open / close hand 8, FIG. 5B is a front view of the open / close hand 8, and FIG. 5C is a side view of the open / close hand 8. FIG.

  The open / close hand 8 is attached to the vacant wrist shaft flange 2 by removing the above-described dedicated jig 3 for TCP setting shown in FIG. 1 from the wrist shaft flange 2 of the articulated robot 1 shown in FIG. The opening / closing hand 8 moves the casing 81 attached to the wrist shaft flange 2, a fixed claw 82 fixed to the casing 81, a moving claw 83 that can move toward and away from the fixed claw 82, and the moving claw 83. And a cylinder 84 as an actuator.

  The fixed claw 82 has a root portion 82a fixed to the casing 81 and a pin portion 82b provided on the root portion 82a. In this embodiment, the root portion 82a is provided with one pin portion 82b, but two or more pins may be provided. The root portion 82a is formed with a recess 82c for gripping a TCP setting jig 9 to be described later.

On the other hand, the moving claw 83 is provided on the slide block 11 that engages with a guide (linear guide) 10 provided in the casing 81 and is slidable along the guide 10, and is fixed to the slide block 11. It has a root portion 83a and a pin portion 83b provided on the root portion 83a. In the present embodiment, the root portion 83a is provided with two pin portions 83b, but may be one or three or more. The root portion 83a has a recess 83c for gripping a TCP setting jig 9 to be described later.

  The slide block 11 and the expansion / contraction rod 84a of the cylinder 84 are connected by the coupling metal 12, and the expansion / contraction of the expansion / contraction rod 84a of the cylinder 84 moves the slide block 11, and the moving claw 83 is separated from the fixed claw 82. It is supposed to be.

(Jig for TCP setting)
FIG. 6 shows a TCP setting jig 9 held by such an open / close hand 8. 6A is a plan view of the jig 9, FIG. 6B is a cross-sectional view taken along the line bb of FIG. 6A, and FIG. 6C is a side view of the jig.

  The jig 9 includes a substantially rectangular plate body 92 to which a reference pin 9 having a sharp tip 91a is attached to the lower surface, a frame plate 94 attached to the upper surface of the plate body 92 via a pair of attachment plates 93, A gripped portion (attachment portion) 95 attached to the upper surface of the frame plate 94 is provided. The gripped portion 95 is formed in a columnar shape, and is attached to the upper surface of the frame plate by a metal fitting 96.

  A fixed claw 82 and a moving claw 83 of the opening / closing hand 8 are inserted into the window 94a of the frame plate 94, and in this state, the moving claw 83 is separated from the fixed claw 82, so that the recess 83c of the moving claw 83 and The concave portion 82 c of the fixed claw 82 is engaged with the gripped portion 95 of the jig 9 so that the jig 9 is gripped by the opening / closing hand 8. When releasing the jig 9 from the opening / closing hand 8, the moving claw 83 is brought close to the fixed claw 82, and the concave portion 83 c of the moving claw 83 and the concave portion 82 c of the fixed claw 82 are separated from the gripped portion 95 of the jig 9.

(TCP setting method)
In the TCP setting method according to this embodiment, first, a tool 5 (open / close hand 8) is attached to the wrist shaft flange 2 of the articulated robot 1 with a bolt and nut or the like, and a TCP setting jig 9 is attached to the open / close hand 8. Hold it. At this time, the concave portion 83c of the moving claw 83 and the concave portion 82c of the fixed claw 82 are engaged with the grasped portion 95 of the jig 9, so that the holding position of the jig 9 can be accurately determined.

  Next, by operating the articulated robot 1, the tip 91a of the reference pin 91 of the jig 9 is moved to the reference point 4a of the reference jig 4 as shown in FIG. 2, and has already been described with reference to FIG. In this way, TCP setting work is performed. Thereafter, the jig 9 is removed from the opening / closing hand 8, and the workpiece is gripped by the opening / closing hand 8 from which the jig 9 has been removed.

(Action / Effect)
Also in this embodiment, a jig 9 for performing TCP setting is attached to the tool 5 without removing the tool 5 (opening / closing hand 8) from the wrist shaft flange 2 of the articulated robot 1 as in the previous embodiment. The TCP setting work is performed, and the jig 9 is removed from the tool 5 after the work is completed. For this reason, after the TCP setting work is completed, the work by the tool 5 (work gripping work by the opening / closing hand 8) can be performed promptly. In addition, since the tool 5 remains fixed to the wrist shaft flange 2, even if the TCP setting operation is performed, the mounting position of the tool 5 on the wrist shaft flange 2 is unlikely to occur.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the above-described embodiments, and various modifications within the scope of the claims. Needless to say, examples and modifications also belong to the technical scope of the present invention.

  The present invention relates to a tool center point setting method for an articulated robot and a tool for setting a tool coordinate system for a tool attached to a wrist axis flange based on a flange coordinate system set for a wrist axis flange of an articulated robot. It can be used for the jig construction for setting the center point.

1 Articulated robot (6-axis articulated robot)
2 Wrist shaft flange 4 Reference jig 4a Reference point 5 Tool 6 Suction pad 63a Screw part (female screw part)
7 Jig 74 Mounting part 8 Opening and closing hand 9 Jig 95 Mounting part (gripped part)
XF Flange coordinate system YF Flange coordinate system ZF Flange coordinate system XT Tool coordinate system YT Tool coordinate system ZT Tool coordinate system

Claims (2)

A tool center point setting method for setting a tool coordinate system for a tool attached to the wrist axis flange based on a flange coordinate system set for a wrist axis flange of an articulated robot,
The wrist axis flange, as the tool, fitted with a suction pad for attracting and holding the workpiece, the said suction pad, the jig attached to cover the workpiece abutting part, by operating the articulated robot, A tool center point setting operation is performed for setting the tool coordinate system based on the flange coordinate system by moving the jig to a pointed reference point of a reference jig installed on the floor on which the articulated robot is installed. ,
A tool center point setting method for an articulated robot, wherein the jig is removed from the suction pad . Based on the flange coordinate system set on the wrist axis flange of the articulated robot, a jig mounting structure used when setting the tool coordinate system with the tool attached to the wrist axis flange,
A tool mounted on the wrist shaft flange of the multi-joint robot; and a jig mounted on the tool. The jig is installed by operating the multi-joint robot. It is moved to a sharp reference point of a reference jig installed on the floor,
The tool is a suction pad for sucking and holding a workpiece, and the jig is detachably attached to the suction pad so as to cover a workpiece contact portion of the suction pad,
For setting a tool center point in an articulated robot, wherein the jig can be attached to and detached from the suction pad without removing the suction pad attached to the wrist shaft flange from the wrist shaft flange. Jig mounting structure.

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