JP2022056009A - Robot, hand mechanism, and operation method of robot - Google Patents

Abstract

To provide a robot which enables improvement of flexibility for handling a workpiece, and to provide a hand mechanism and an operation method of the robot.SOLUTION: A robot 7 includes: a horizontal multi-joint type arm 11; a hand 13 which is provided at a tip of the arm 11 and includes laminated permanent magnets 35 ; and a connection mechanism 29 which connects the hand 13 to a tip part of the arm 11 so that the hand 13 may rotate around a rotation axis Ax4 and the rotation axis Ax4 may incline relative to a reference axis Ax5 fixed in a preset direction.SELECTED DRAWING: Figure 5

Description

The embodiments of the disclosure relate to a robot, a hand mechanism, and a working method of the robot.

Patent Document 1 describes an elevating arm, a first swivel arm rotatably attached to the tip of the elevating arm, and a second swivel arm rotatably attached to the tip of the first swivel arm. A horizontal articulated robot having a hand rotatably attached to the tip of a second swivel arm and gripping a work to be transported by a transport table is described.

Jikkenhei 3-12691 Gazette

In the horizontal articulated robot, it has been desired to improve the flexibility to the work.

The present invention has been made in view of such problems, and an object of the present invention is to provide a robot, a hand mechanism, and a robot working method capable of improving flexibility for a work.

In order to solve the above problems, according to one aspect of the present invention, the horizontal articulated arm, the hand provided at the tip of the arm, and the hand can be rotated around a rotation axis. Moreover, a robot having a connecting mechanism connected to the tip end portion of the arm so that the rotation axis can be tilted with respect to a reference axis in a preset direction is applied.

Further, according to another aspect of the present invention, it is a hand mechanism provided at the tip of the horizontal articulated arm provided in the robot, and the hand for operating the work and the hand are placed around the rotation axis. A hand mechanism having a connecting mechanism connected to the tip of the arm is applied so that the rotation axis can be rotated and the rotation axis can be tilted with respect to a reference axis in a preset direction.

Further, according to another aspect of the present invention, it is a robot work method in which a robot equipped with a horizontal articulated arm is made to perform a predetermined work, and a hand provided at the tip of the arm is used as a work. When the hand is moved to abut and the work is operated, the hand is rotated around a rotation axis and the rotation axis is tilted with respect to a reference axis in a preset direction. The working method of the robot having, is applied.

According to the robot or the like of the present invention, the flexibility to the work can be improved.

It is a front view which shows an example of the whole structure of the robot system which concerns on embodiment. It is a vertical cross-sectional view which shows an example of the structure of the 3rd arm part of the arm of the robot which concerns on embodiment, and the structure of a hand mechanism. It is a top view which shows an example of the structure of the connection mechanism seen from the upper side in the vertical direction. FIG. 3 is a vertical cross-sectional view showing an example of a cross-sectional configuration corresponding to an IV-IV cross section in FIG. It is a vertical cross-sectional view which shows an example of the cross-sectional structure of the hand mechanism in the state where the rotation axis of a hand is inclined with respect to a reference axis. It is a vertical cross-sectional view which shows an example of the cross-sectional structure of the hand mechanism in the state which the hand moves in the axial direction along the rotation axis or the reference axis. It is a vertical cross-sectional view which shows an example of the cross-sectional structure of the hand mechanism seen from the horizontal direction in the modification which provides the cylindrical member inside the spring. It is a vertical cross-sectional view which shows an example of the cross-sectional structure of the hand mechanism in the state where the rotation axis of a hand is inclined with respect to the reference axis in the modification which provides the cylindrical member inside the spring. It is a top view which shows an example of the structure of the connecting mechanism seen from the upper side in the vertical direction in the modified example in which a spring is provided at a place different from a bolt. 9 is a vertical cross-sectional view showing an example of a cross-sectional configuration corresponding to an XX cross section in FIG. 9. 9 is a vertical cross-sectional view showing an example of a cross-sectional configuration corresponding to the XI-XI cross section in FIG. 9. It is a vertical cross-sectional view which shows an example of the cross-sectional structure of the hand mechanism in the state where the rotation axis of a hand is inclined with respect to the reference axis in the modification which provides the spring in the place different from the bolt. It is a vertical cross-sectional view which shows an example of the cross-sectional structure of the hand mechanism seen from the horizontal direction in the modification which makes the taper of a through hole a curved surface shape. It is a vertical cross-sectional view which shows an example of the cross-sectional structure of the hand mechanism seen from the horizontal direction in the modification which installs a hand outside the housing. It is a vertical cross-sectional view which shows an example of the cross-sectional structure of the hand mechanism in the state where the rotation axis of a hand is inclined with respect to the reference axis in the modification which installs a hand outside the housing. It is a side view which shows an example of the whole structure of the robot system in the case of opening and closing a sliding door. It is a front view which shows an example of the whole structure of the robot system in the case of pushing a hand against a door to perform opening and closing work.

Hereinafter, one embodiment will be described with reference to the drawings.

<1. Robot system configuration>
First, an example of the configuration of the robot system according to the present embodiment will be described with reference to FIG. For convenience of explanation, FIG. 1 shows an orthogonal coordinate system consisting of a Z-axis having a vertical upward direction as a positive direction, an X-axis having a positive direction as a work transport direction, and a Y-axis perpendicular to each of the Z-axis and the X-axis. It is shown in the figure.

As shown in FIG. 1, the robot system 1 has a transfer device 5 for transporting a work 3 and a robot 7.

The work 3 is, for example, a vehicle body of an automobile, and has doors 9 which are opening / closing members on both sides in the Y-axis direction. The transport device 5 transports the work 3 in the positive direction of the X-axis. The transport of the work 3 is continuously executed at a predetermined constant speed without stopping in the middle.

The robot 7 is a so-called SCARA robot, and has a horizontal articulated arm 11 and a hand 13 provided at the tip of the arm 11. The robot 7 opens the door 9 of the work 3 being conveyed, and keeps the open state while the predetermined work is executed on the work 3 by another work device (not shown), and the predetermined work is completed. After that, the door 9 is closed and the opening / closing work is executed. The predetermined work is, for example, a painting work on the work 3. It should be noted that the door 9 opening / closing work may be executed during work other than painting work such as welding work and fitting work.

The arm 11 has a base portion 15, a first arm portion 17, a second arm portion 19, and a third arm portion 21.

The base portion 15 is fixed to the traveling table 23. The pedestal 23 can move along the guide 25 in the positive and negative directions of the X-axis. As a result, the robot 7 can move so as to follow the work 3 conveyed by the transfer device 5.

The first arm portion 17 is rotatably connected to the base portion 15 around the first axis Ax1 substantially parallel to the Z axis. The second arm portion 19 is connected to the tip end side of the first arm portion 17 so as to be rotatable around the second axis Ax2 substantially parallel to the Z axis. The second arm portion 19 has a horizontal extension portion 19a extending in a substantially horizontal direction and a vertical extension portion 19b extending upward in a substantially vertical direction from the tip end side of the horizontal extension portion 19a. The vertically extending portion 19b has a built-in elevating mechanism (not shown) for elevating and lowering the third arm portion 21 along the third axis Ax3.

The third arm portion 21 is connected to the upper end portion of the vertically extending portion 19b of the second arm portion 19, and is provided so as to project substantially horizontally from the upper end portion. The third arm portion 21 moves up and down along the third axis Ax3.

A hand 13 is provided at the tip of the third arm portion 21 so as to project downward in a substantially vertical direction. The hand 13 is a kind of end effector for opening and closing the door 9. Although the details will be described later, the hand 13 is an elongated rod-shaped member extending in the longitudinal direction, and has a flat side surface 37a (described later) that contacts the inside of the door 9 of the work 3 on the side perpendicular to the longitudinal direction (horizontal side). (See FIGS. 3 to 6). The robot 7 opens and closes the door 9 by attracting the side surface 37a of the hand 13 to the inside of the door 9 with a magnet.

The robot 7 having the above configuration is a three-axis robot having two rotation axes of the first axis Ax1 and the second axis Ax2 and one elevating axis of the third axis Ax3. In addition to the above three axes, for example, the third arm portion 21 may be rotatable around the third axis Ax3, and the robot 7 may be configured as a four-axis robot. Then, the robot 7 touches the hand 13 provided at the tip of the arm 11 to the inside of the door 9 of the work 3, and when the hand 13 is moved to open and close the door 9. A work method including a step of rotating around the rotation axis Ax4 and tilting the rotation axis Ax4 with respect to a reference axis Ax5 in a preset direction is executed.

The configuration of the robot system 1 described above is an example, and is not limited to the above contents. For example, the transport of the work 3 by the transport device 5 may be stopped intermittently during the execution of a predetermined work on the work 3 by the work device or the opening / closing work of the door 9 by the robot 7. In this case, the robot 7 may be fixedly installed instead of being movablely installed.

<2. Hand mechanism configuration>
Generally, the SCARA robot has a low degree of freedom in the hand provided at the tip of the arm. For this reason, when the work transported by the transport device is manually operated, for example, an error in the mounting position of the work on the transport device, tilting or meandering of the transport device itself, and choco-stopping (stopping for a short time). When the work position shifts or the position / speed fluctuates due to knocking, etc., the hand cannot absorb them, and the work is damaged or deformed. There is a possibility that problems such as abnormal stoppage of the robot may occur.

In the robot 7 of the present embodiment, the hand 13 can rotate around a rotation axis Ax4 (see FIGS. 4 to 6 described later) substantially parallel to the Z axis, and the rotation axis Ax4 is a reference axis Ax5 (described later). It is connected to the tip of the arm 11 so as to be tiltable with respect to (see FIG. 5). Since the hand 13 can rotate in this way, it is possible to flexibly respond to a change in the posture (angle) of the door 9 when the door 9 is opened and closed. Further, since the hand 13 can be tilted, even if the above-mentioned positional deviation, position / speed fluctuation, or the like occurs in the transported work 3, the hand 13 can be tilted so as to bend and absorb them. .. Therefore, the flexibility for the work 3 can be improved.

Hereinafter, an example of the configuration of the hand mechanism that enables the rotation and tilting of the hand 13 will be described in detail with reference to FIGS. 2 to 6.

FIG. 2 shows an example of the internal structure of the third arm portion 21 and the configuration of the hand mechanism 31 in the arm 11 of the robot 7. As shown in FIG. 2, a rod-shaped hand 13 penetrates in a substantially vertical direction through a housing base portion 27a (an example of a housing) provided at the lower end side of the housing 27 of the third arm portion 21. It is provided to do so. The hand 13 is attached to the housing base portion 27a by the connecting mechanism 29 so that the rotation axis Ax4 can rotate around the rotation axis Ax4 and the rotation axis Ax4 can be tilted with respect to the reference axis Ax5 in the preset direction. It is connected. Further, the hand 13 is connected to the housing base portion 27a by a connecting mechanism 29 so as to be movable in the axial direction along the rotation axis Ax4 or the reference axis Ax5. The hand mechanism 31 is composed of the hand 13 and the connecting mechanism 29 and the like.

Inside the housing 27, a limit switch 33 is provided in the vicinity of the connecting mechanism 29. The limit switch 33 has a lever 33b that projects outward through an opening (not shown) formed in the housing base portion 27a and is rotatable in the direction of arrow R about the rotating portion 33a. The lever 33b is in a vertical downward posture when the hand 13 is not in contact with the inside of the door 9 (indicated by a solid line in FIG. 2), and when the hand 13 is in contact with the inside of the door 9. Is in a posture of contacting the inside of the door 9 and rotating in the direction of arrow R from the downward direction in the vertical direction (indicated by the broken line in FIG. 2). As a result, the limit switch 33 detects whether or not the hand 13 is in contact with the door 9. The limit switch 33 outputs the detected result as a detection signal to the controller (not shown) via a cable (not shown) arranged inside the housing 27.

FIG. 3 shows an example of a configuration in which the connecting mechanism 29 is viewed from above in the vertical direction, and FIG. 4 shows an example of a cross-sectional configuration in which the hand mechanism 31 is viewed from the horizontal direction. Further, FIG. 5 shows an example of a state in which the rotation axis Ax4 of the hand 13 is tilted with respect to the reference axis Ax5, and FIG. 6 shows a state in which the hand 13 moves in the axial direction along the rotation axis Ax4 or the reference axis Ax5. An example is shown. Note that FIG. 4 shows a cross-sectional structure corresponding to the IV-IV cross section in FIG.

As shown in FIGS. 3 and 4, the hand 13 has a plurality of permanent magnets 35, a cover 37, a holding portion 39, a support portion 41, and a brim portion 43. As shown in FIG. 3, the cover 37 is a square cylindrical member formed so that the shape of the rotating shaft Ax4 or the reference shaft Ax5 when viewed from the axial direction is rectangular, and is made of a non-magnetic material such as stainless steel. It is configured. The cover 37 has, for example, four flat side surfaces 37a that come into contact with the inside of the door 9 on the side perpendicular to the axial direction. The plurality of permanent magnets 35 are laminated in the cover 37 so that the same magnetic poles of the adjacent permanent magnets 35 face each other in the stacking direction. That is, the permanent magnets 35 are laminated so that the N poles of the adjacent permanent magnets 35 face each other and the S poles of the adjacent permanent magnets 35 face each other in the axial direction of the rotation axis Ax4 or the reference axis Ax5. There is. As a result, as shown in FIG. 4, loops 45 of magnetic field lines are formed for each of the adjacent permanent magnets 35, and even if any part in the axial direction on the side surface 37a comes into contact with the inside of the door 9, a substantially constant attractive force is applied. Obtainable.

As shown in FIG. 3, the holding portion 39 is formed into a rectangular shape whose shape seen from the axial direction is one size larger than that of the cover 37, and as shown in FIG. 4, the holding portion 39 is seen from a direction perpendicular to the axial direction. The shape is formed in a substantially U shape, and the upper end portion of the cover 37 is connected to the inside. The support portion 41 is formed in a columnar shape having a substantially circular shape when viewed from the axial direction, and is connected to the upper end portion of the holding portion 39. The support portion 41 is provided so as to penetrate the housing base portion 27a. The brim portion 43 is formed in a substantially circular shape having a diameter larger than that of the support portion 41 when viewed from the axial direction, and is connected to the upper end of the support portion 41.

The connecting mechanism 29 has a flange 47, a bearing member 49, a plurality of pin members 51, a plurality of springs 53, a plurality of washers 55, and a plurality of spring receiving members 57. The flange 47 (an example of a transmission member) plays a role of transmitting the elastic force of the spring 53 to the hand 13. The flange 47 has a cylindrical tubular portion 47a and a substantially circular flange portion 47b provided at the upper end of the tubular portion 47a. The tubular portion 47a is provided so as to cover the outer periphery of the support portion 41 of the hand 13, and is fitted into a through hole 59 formed in the housing base portion 27a. The tubular portion 47a of the flange 47 covers the entire outer circumference of the support portion 41 of the hand 13 in the circumferential direction, but does not need to cover the entire circumference in the axial direction, and may cover at least a part thereof. Further, the tubular portion 47a and the through hole 59 are not fitted without a gap, but a minute gap is provided so that the hand 13 can be tilted. Further, on the inner peripheral surface of the through hole 59, tapered portions 61 having a tapered shape toward the inside are formed on both sides in the drilling direction (both sides in the axial direction of the rotation axis Ax4 or the reference axis Ax5). The tapered portion 61 is formed over the entire circumferential direction (360 °) around the rotation axis Ax4 or the reference axis Ax5. As a result, a space for the hand 13 to tilt can be secured inside the through hole 59.

The bearing member 49 is provided between the hand 13 and the flange 47, and rotatably supports the hand 13 around the rotation shaft AX4. The bearing member 49 is a plain bearing (bush) that receives the rotation of the support portion 41 of the hand 13 while sliding. The inner diameter of the bearing member 49 (the same applies to the inner diameter of the tubular portion 47a of the flange 47) is smaller than the outer diameter of the brim portion 43 of the hand 13, and the brim portion 43 is connected by the hand 13 toward the tip side in the axial direction. It plays the role of a retaining mechanism to prevent the mechanism 29 from coming off. A bearing such as a ball bearing or a roller bearing may be used as the bearing member 49.

The spring 53 (an example of an elastic member) is provided between the flange portion 47b of the flange 47 and the housing base portion 27a. A spring receiving member 57 is provided between the upper end portion of each spring 53 and the brim portion 47b. As shown in FIG. 3, the number of springs 53 is the same as that of the pin members 51 (for example, six), and the springs 53 are arranged at a plurality of locations (for example, approximately 60 ° intervals) along the circumferential direction around the rotation axis Ax4 or the reference axis Ax5. Has been done. The spring 53 is a so-called compression spring, which receives an external force in the compression direction and generates a reaction force. The number of springs 53 and pin members 51 may be other than six.

The pin member 51 (an example of a fastening member and a regulating member) penetrates the flange portion 47b of the flange 47, is inserted inside the spring 53, and is fastened to the housing base portion 27a. As shown in FIG. 3, the number of pin members 51 is the same as that of the spring 53 (for example, six), and the pin members 51 are arranged at a plurality of locations (for example, approximately 60 ° intervals) along the circumferential direction around the rotation axis Ax4 or the reference axis Ax5. Has been done. The pin member 51 has a screw portion 51a having a thread formed on the outer periphery and fastened to the screw hole 63 of the housing base portion 27a, a shaft portion 51b formed having a diameter larger than that of the screw portion 51a, and a shaft portion 51b. Also has a head 51c formed with a large diameter. The head portion 51c abuts on the flange portion 47b of the flange 47 via the washer 55. Further, at least a part of the shaft portion 51b is inserted inside the spring 53 between the flange portion 47b of the flange 47 and the housing base portion 27a. The outer peripheral surface of the shaft portion 51b is a smooth cylindrical surface without screws, and even if the spring 53 comes into contact with the spring 53, it slides without being caught. As a result, the pin member 51 regulates the expansion / contraction direction of the spring 53 in the axial direction of the shaft portion 51b.

With the above configuration, as shown in FIG. 5, the connecting mechanism 29 has a restoring force (in other words,) for the hand 13 in which the rotation axis Ax4 is tilted with respect to the reference axis Ax5 to return to the posture before tilting. And the restoring force in the tilting direction. An example of the first restoring force) is applied. That is, the connecting mechanism 29 transmits the elastic force of the plurality of springs 53 to the hand 13 so that the restoring force is applied to the hand 13 in an inclined posture. The "posture before tilting" is a posture in which the rotation axis Ax4 substantially coincides with the reference axis Ax5. The rotation axis Ax4 tilts in conjunction with the tilt of the hand 13, whereas the reference axis Ax5 is fixed in a preset direction regardless of the tilt of the hand 13. That is, the reference axis Ax5 is the direction of the initial posture of the hand 13 in a state where no external force is applied to the hand 13 (a state in which the hand 13 does not attract the door 9), for example, the extension of the third arm portion 21. The direction is perpendicular to the direction.

Further, as shown in FIG. 5, the upper edge portion of the flange portion 47b of the flange portion 47 in the inclined direction is restricted from moving upward by abutting on the washer 55. On the other hand, the lower edge portion of the brim portion 47b in the inclined direction moves downward by the abutting spring receiving member 57 descending to the position where the spring 53 is fully compressed (the position where the spring 53 is most compressed). Is regulated. As a result, the connecting mechanism 29 limits the angle range in which the hand 13 can be tilted to a predetermined angle range θ. In addition to the above, the angle range may be restricted by adjusting the diameter of the through hole 65 for penetrating the pin member 51 formed in the flange portion 47b of the flange 47, for example, the tapered portion 61. The angle range may be regulated by the angle of.

Further, according to the above configuration, as shown in FIG. 6, the connecting mechanism 29 is located on the upper side in the axial direction (an example of one side) with respect to the hand 13 that has moved toward the lower side in the axial direction (an example of one side) of the rotation axis Ax4 or the reference axis Ax5. A restoring force (in other words, an axial restoring force; an example of a second restoring force) that tries to return toward the other side) is applied. That is, the connecting mechanism 29 transmits the elastic force of the plurality of springs 53 to the hand 13 so that the restoring force is applied to the hand 13 that has moved downward in the axial direction.

Further, as shown in FIG. 6, the flange portion 47b of the flange 47 is restricted from moving upward by abutting on the washer 55. On the other hand, the brim portion 47b is restricted from moving downward by the abutting spring receiving member 57 descending to a position where the spring 53 is fully compressed (a position where the spring 53 is most compressed). As a result, the connecting mechanism 29 limits the range in which the hand 13 can move in the axial direction to a predetermined range D.

<3. Effect of embodiment>
As described above, the robot 7 according to the present embodiment can rotate the horizontal articulated arm 11, the hand 13 provided at the tip of the arm 11, and the hand 13 around the rotation axis Ax4. It also has a connecting mechanism 29 that connects to the tip of the arm 11 so that the rotation axis Ax4 can be tilted with respect to the reference axis Ax5 in a preset direction.

Since the hand 13 can rotate, it is possible to flexibly respond to a change in posture when opening and closing the door 9 of the work 3. Further, since the hand 13 can be tilted, even if the work 3 to be conveyed is displaced or the position / speed fluctuates, the hand 13 can be tilted so as to bend and absorb them. Therefore, the flexibility for the work 3 can be improved.

Further, in the present embodiment, in particular, the connecting mechanism 29 imparts a restoring force to the hand 13 in a posture in which the rotation axis Ax4 is tilted with respect to the reference axis Ax5 to return to the posture before the tilt. It is configured in. As a result, the hand 13 is tilted when an external force is generated on the hand 13 due to a positional deviation of the work 3 to be conveyed, a fluctuation in the position / speed, or the like, and when no external force is generated, the hand 13 is tilted in the initial posture (tilted). It is possible to return to the posture that is not done. Therefore, the position accuracy of the hand 13 can be ensured.

Further, in the present embodiment, in particular, the connecting mechanism 29 is configured to limit the angle range in which the hand 13 can be tilted to a predetermined angle range θ. As a result, it is possible to prevent the hand 13 from being excessively tilted and causing a problem.

Further, in the present embodiment, in particular, the connecting mechanism 29 has a spring 53, and the elastic force of the spring 53 is transmitted to the hand 13 so that the restoring force is applied to the hand 13 in an inclined posture. It is configured. As a result, when an external force is generated on the hand 13, the hand 13 is tilted, and when no external force is generated, the elastic force of the spring 53 is used to return the hand 13 to the initial posture (non-tilted posture). be able to. Therefore, the position accuracy of the hand 13 can be ensured.

Further, in the present embodiment, in particular, the connecting mechanism 29 connects the hand 13 to the tip end portion of the arm 11 so as to be movable in the axial direction along the rotation axis Ax4 or the reference axis Ax5. As a result, even if the work 3 to be conveyed is displaced in the vertical direction or the position / speed fluctuates, the hand 13 can be moved in the axial direction to absorb them. Therefore, the flexibility for the work 3 can be further improved.

Further, in the present embodiment, in particular, the connecting mechanism 29 is configured to apply a restoring force that tends to return the hand 13 that has moved downward in the axial direction toward the upper side in the axial direction. .. As a result, the hand 13 is moved when an axial external force is generated on the hand 13 due to a vertical displacement of the conveyed work 3 or a change in position / speed, and when no external force is generated, the hand is moved. 13 can be returned to the initial position (the position that has not moved in the axial direction). Therefore, the position accuracy of the tip of the hand 13 can be ensured.

Further, in the present embodiment, in particular, the connecting mechanism 29 is configured to limit the range in which the hand 13 can move in the axial direction to a predetermined range D. As a result, it is possible to prevent the hand 13 from moving excessively in the axial direction and causing a problem.

Further, in the present embodiment, in particular, the connecting mechanism 29 has a spring 53, and the elastic force of the spring 53 is transmitted to the hand 13 so that the restoring force is applied to the hand 13 that has moved in the axial direction. It is configured in. As a result, the hand 13 is moved when an axial external force is generated on the hand 13, and when no external force is generated, the hand 13 is moved to the initial position (axially) by using the elastic force of the spring 53. It can be returned to the position where it does not exist. Therefore, the position accuracy of the tip of the hand 13 can be ensured.

Further, in the present embodiment, in particular, the connecting mechanism 29 has a spring 53 and a flange 47 that transmits the elastic force of the spring 53 to the hand 13, and the spring 53 is between the flange 47 and the housing base portion 27a. It is provided in. As a result, the elastic force of the spring 53 can be generated between the housing base portion 27a and the flange 47, and this elastic force can be transmitted to the hand 13 via the flange 47. As a result, when the work 3 is displaced or the position / speed fluctuates, the hand 13 is tilted / moved to absorb them, and the restoring force to return to the original posture / position is applied to the hand 13. Can be granted.

Further, in the present embodiment, in particular, the connecting mechanism 29 has a bearing member 49 between the hand 13 and the flange 47 that rotatably supports the hand 13 around the rotation shaft Ax4. As a result, since the hand 13 can rotate with respect to the flange 47, it is possible to realize a connecting mechanism 29 that rotatably connects the hand 13 to the arm 11 around the rotation axis Ax4. Further, the rotational operation of the hand 13 can be blocked from being transmitted to the flange 47, and the flange 47 with which the spring 53 comes into contact can be fixed to the housing base portion 27a. Therefore, it is possible to prevent the spring 53 from hindering the rotation of the hand 13, and the hand 13 can be smoothly rotated.

Further, in the present embodiment, in particular, the hand 13 has a support portion 41 provided so as to penetrate the housing base portion 27a, and the bearing member 49 rotatably supports the support portion 41. As a result, the bearing member 49 can be installed inside the housing base portion 27a, and damage to the bearing member 49 due to foreign matter (dust, moisture, metal powder, etc.) invading from the outside can be prevented. Further, for example, when painting work is performed on the work 3, the robot 7 can have an explosion-proof structure.

Further, in the present embodiment, in particular, the flange 47 is provided so as to cover at least a part of the outer periphery of the support portion 41, and is fitted into the through hole 59 formed in the housing base portion 27a. As a result, the through hole 59 formed in the housing base portion 27a can be closed by the flange 47 to prevent foreign matter from entering the housing base portion 27a.

Further, in the present embodiment, in particular, the through hole 59 has tapered portions 61 having a tapered shape toward the inside on both sides of the inner peripheral surface in the drilling direction. As a result, a space for the hand 13 to tilt can be secured inside the through hole 59.

Further, in the present embodiment, in particular, the connecting mechanism 29 is arranged between the flange 47 and the housing base portion 27a, and has a pin member 51 that regulates the expansion / contraction direction of the spring 53. As a result, the tilting motion of the hand 13 and the moving motion in the axial direction can be stabilized.

Further, in the present embodiment, in particular, the pin member 51 penetrates the flange portion 47b of the flange 47, is inserted into the inside of the spring 53, and is fastened to the housing base portion 27a. As a result, the member that connects the flange 47 to the housing base portion 27a and the member that regulates the expansion / contraction direction of the spring 53 can be shared, and the number of parts can be reduced.

Further, in the present embodiment, in particular, the connecting mechanism 29 has a plurality of springs 53, and the plurality of springs 53 are arranged at a plurality of locations along the circumferential direction around the reference axis Ax5. As a result, a substantially uniform restoring force can be applied to the hand 13 regardless of the direction in which the hand 13 is tilted about the reference axis Ax5.

Further, in this embodiment, in particular, the hand 13 has a permanent magnet 35. As a result, the work 3 which is a magnetic material can be attracted and held by a magnetic force without providing a complicated mechanism such as a gripping mechanism. Further, the tilting of the hand 13 makes it easier to remove the hand 13 from the work 3 against the magnetic force.

Further, in the present embodiment, in particular, the hand 13 has a plurality of permanent magnets 35, and the plurality of permanent magnets 35 are laminated so that the same magnetic poles of adjacent permanent magnets 35 face each other in the stacking direction. ing. As a result, loops 45 of magnetic field lines can be formed for each of the adjacent permanent magnets 35. As a result, a substantially constant suction force can be obtained regardless of which part of the hand 13 in the axial direction comes into contact with the inside of the door 9.

Further, in the present embodiment, in particular, the hand 13 is a rod-shaped member extending in the longitudinal direction, and has a flat side surface 37a in contact with the door 9 of the work 3 on the side perpendicular to the longitudinal direction. As a result, the side surface 37a of the hand 13 can be easily brought into contact with the door 9 by rotating and tilting the hand 13 so that the posture corresponds to the door 9. Further, by making the side surface 37a in contact with the door 9 a flat surface, surface contact is possible between the side surface 37a and the door 9, and the contact area can be increased, so that the attractive force due to the magnetic force can be improved.

<4. Modification example>
The embodiments of the disclosure are not limited to the above, and various modifications can be made within the range not deviating from the purpose and the technical idea. Hereinafter, such modification examples will be described.

(4-1. When a tubular member is provided inside the spring)
In the above embodiment, the expansion / contraction direction of the spring 53 is restricted by the pin member 51, but the present invention is not limited to this, and for example, a tubular member may be provided inside the spring 53.

FIG. 7 shows an example of a cross-sectional configuration of the hand mechanism 31A according to this modification when viewed from the horizontal direction. Further, FIG. 8 shows an example of a state in which the rotation axis Ax4 of the hand 13 is tilted with respect to the reference axis Ax5 in the hand mechanism 31A.

As shown in FIG. 7, the connecting mechanism 29A has a plurality of bolts 67 and a plurality of tubular members 69 in place of the plurality of pin members 51 described above. The other configurations of the flange 47, the bearing member 49, the spring 53, the washer 55, the spring receiving member 57, the hand 13, and the like are the same as those in the above-described embodiment.

The bolt 67 penetrates the flange portion 47b of the flange 47, is inserted into the inside of the tubular member 69, and is fastened to the housing base portion 27a. The number of bolts 67 is the same as that of the springs 53 (for example, six), and the bolts 67 are arranged at a plurality of places (for example, approximately 60 ° intervals) along the circumferential direction around the rotation axis Ax4 or the reference axis Ax5. The bolt 67 has a screw portion 67a having a thread formed on the outer periphery thereof and fastened to the screw hole 63 of the housing base portion 27a, and a head portion 67b formed having a diameter larger than that of the screw portion 67a. The head portion 67b abuts on the flange portion 47b of the flange 47 via the washer 55.

The tubular member 69 (an example of a regulating member) is a cylindrical member and is also referred to as a collar. The tubular member 69 is arranged inside the spring 53, and the upper end portion is in contact with the washer 55 and the lower end portion is in contact with the housing base portion 27a. At least a part of the tubular member 69 is inserted inside the spring 53 between the flange portion 47b of the flange 47 and the housing base portion 27a. The tubular member 69 covers the outer circumference of the threaded portion 67a of the bolt 67, and the outer peripheral surface thereof is a smooth cylindrical surface so that the spring 53 can slide without being caught even if it comes into contact with the spring 53. As a result, the tubular member 69 restricts the expansion / contraction direction of the spring 53 in the axial direction of the tubular member 69.

With the above configuration, as shown in FIG. 8, the connecting mechanism 29A has a restoring force (tilt) that tries to return the hand 13 in a posture in which the rotation axis Ax4 is tilted with respect to the reference axis Ax5 to the posture before the tilt. Directional restoring force. An example of the first restoring force) is applied. That is, the connecting mechanism 29A transmits the elastic force of the plurality of springs 53 to the hand 13 so that the restoring force is applied to the hand 13 in the inclined posture. Further, as shown in FIG. 8, the upper edge portion of the flange portion 47b of the flange portion 47 in the inclined direction is restricted from moving upward by abutting on the washer 55. On the other hand, the lower edge portion of the brim portion 47b in the inclined direction moves downward by the abutting spring receiving member 57 descending to the position where the spring 53 is fully compressed (the position where the spring 53 is most compressed). Is regulated. As a result, the connecting mechanism 29 limits the angle range in which the hand 13 can be tilted to a predetermined angle range θ.

Although not shown, the connecting mechanism 29A has an upper side in the axial direction (an example on the other side) with respect to the hand 13 that has moved toward the lower side in the axial direction (an example on one side) of the rotation axis Ax4 or the reference axis Ax5. ), A restoring force (axial restoring force; an example of a second restoring force) is applied. That is, the connecting mechanism 29A transmits the elastic force of the plurality of springs 53 to the hand 13 so that the restoring force is applied to the hand 13 that has moved downward in the axial direction. At this time, the flange portion 47b of the flange 47 is restricted from moving upward by abutting on the washer 55. On the other hand, the brim portion 47b is restricted from moving downward by the abutting spring receiving member 57 descending to a position where the spring 53 is fully compressed (a position where the spring 53 is most compressed). As a result, the connecting mechanism 29A limits the range in which the hand 13 can move in the axial direction to a predetermined range D.

According to the modification described above, the tubular member 69 is arranged inside the spring 53, and the bolt 67 is inserted inside the tubular member 69. As a result, general-purpose parts can be used for the bolt 67 and the tubular member 69, and the cost can be reduced as compared with the case of using the specially designed parts.

(4-2. When the spring is installed in a place different from the bolt)
In the above modification (4-1), the spring 53 is provided at the same location as the bolt 67 (at the same position in the circumferential direction), but the present invention is not limited to this, and the spring is provided at a location different from the bolt 67. It may be provided in.

FIG. 9 shows an example of a configuration in which the connecting mechanism 29B according to the modified example is viewed from above in the vertical direction, and FIGS. 10 and 11 show an example of a cross-sectional configuration in which the hand mechanism 31B according to the modified example is viewed from the horizontal direction. Is shown. Further, FIG. 12 shows an example of a state in which the rotation axis Ax4 of the hand 13 is tilted with respect to the reference axis Ax5. Note that FIG. 10 shows a cross-sectional configuration corresponding to the XX cross section in FIG. 9, and FIG. 11 shows a cross-sectional configuration corresponding to the XI-XI cross section in FIG.

As shown in FIGS. 9 to 11, the connecting mechanism 29B has a flange 47A instead of the flange 47, and has a plurality of spring rods 71 (an example of an elastic member) instead of the plurality of springs 53. Other configurations of the bolt 67, the tubular member 69, the bearing member 49, the washer 55, the hand 13, and the like are the same as those of the above-mentioned modification (4-1).

The flange 47A (an example of a transmission member) has a cylindrical tubular portion 47Aa and a substantially circular flange portion 47Ab provided at the upper end of the tubular portion 47Aa. As shown in FIG. 9, a plurality of (for example, six) bolts 67 are provided, and are arranged at a plurality of locations (for example, approximately 60 ° intervals) along the circumferential direction around the rotation axis Ax4 or the reference axis Ax5. The number of spring rods 71 is the same as that of the bolts 67 (for example, six), and the spring rods 71 are arranged at a plurality of places (for example, approximately 60 ° intervals) between the bolts 67 and 67 along the circumferential direction around the rotation axis Ax4 or the reference axis Ax5. Has been done. That is, the spring rod 71 and the bolt 67 are arranged at intervals of, for example, approximately 30 °. The number of spring rods 71 and bolts 67 may be other than six.

As shown in FIG. 10, in this modification, a spring is not provided on the outer periphery of the tubular member 69, and the tubular member 69 is provided so as to be exposed. As shown in FIG. 11, the spring rod 71 includes a rod portion 71a that abuts on the housing base portion 27a and a screw portion 71b that has a thread formed on the outer periphery and is fastened to the screw hole 73 of the flange portion 47Ab of the flange 47A. Has. A compression spring is built in the screw portion 71b, and the rod portion 71a is expanded and contracted to receive an external force in the compression direction and generate a reaction force.

With the above configuration, as shown in FIG. 12, the connecting mechanism 29B has a restoring force (tilt) that tries to return the hand 13 in a posture in which the rotation axis Ax4 is tilted with respect to the reference axis Ax5 to the posture before the tilt. Directional restoring force. An example of the first restoring force) is applied. That is, the connecting mechanism 29B transmits the elastic force of the plurality of spring rods 71 to the hand 13 so that the restoring force is applied to the hand 13 in an inclined posture. In this modification, the through hole 75 and the tubular member 69 are formed by adjusting the diameter of the through hole 75 (see FIG. 10) for penetrating the tubular member 69 formed in the flange portion 47Ab of the flange 47A. The gap is adjusted, and the angle range in which the hand 13 can be tilted is restricted to a predetermined angle range θ. The angle range in which the hand 13 can be tilted may be restricted by the stroke of the rod portion 71a of the spring rod 71.

Although not shown, the connecting mechanism 29B has an upper side in the axial direction (an example on the other side) with respect to the hand 13 that has moved toward the lower side in the axial direction (an example on one side) of the rotation axis Ax4 or the reference axis Ax5. ), A restoring force (axial restoring force; an example of a second restoring force) is applied. That is, the connecting mechanism 29B transmits the elastic force of the plurality of spring rods 71 to the hand 13 so that the restoring force is applied to the hand 13 that has moved downward in the axial direction. At this time, the flange portion 47Ab of the flange 47A is restricted from moving upward by abutting on the washer 55. On the other hand, the brim portion 47Ab is restricted from moving downward by descending to the position where the rod portion 71a of the spring rod 71 is fully contracted (the position where the spring rod 71 is most compressed). As a result, the connecting mechanism 29B limits the range in which the hand 13 can move in the axial direction to a predetermined range D.

(4-3. When the taper of the through hole is curved)
In the above embodiment, the flat tapered portion 61 is formed on the inner peripheral surface of the through hole 59 of the housing base portion 27a, but the present invention is not limited to this, and a curved tapered portion may be used.

FIG. 13 shows an example of a cross-sectional configuration of the hand mechanism 31 according to this modification when viewed from the horizontal direction. As shown in FIG. 13, on the inner peripheral surface of the through hole 59 of the housing base portion 27a, tapered portions 61A having a tapered shape toward the inside are formed on both sides in the drilling direction. The tapered portion 61A is formed in a curved surface shape (cross-section R shape), and is formed over the entire circumferential direction (360 °) around the rotation axis Ax4 or the reference axis Ax5. As a result, a space for tilting the hand 13 can be secured inside the through hole 59, and the tilting operation of the hand can be smoothed.

(4-4. When installing the hand outside the housing)
In the above embodiment, the hand 13 is provided so as to penetrate the housing base portion 27a, but the present invention is not limited to this, and the hand 13 may be provided outside the housing base portion 27a.

FIG. 14 shows an example of a cross-sectional configuration of the hand mechanism 31C according to the present modification when viewed from the horizontal direction. Further, FIG. 15 shows an example of a state in which the rotation axis Ax4 of the hand 13 is tilted with respect to the reference axis Ax5 in the hand mechanism 31C.

As shown in FIG. 14, in this modification, the through hole 59 is not formed in the housing base portion 27a, and the connecting mechanism 29C and the hand 13 are provided on the outside (lower part) of the housing base portion 27a. .. The connecting mechanism 29C has a flange 47, a bearing member 49, a plurality of pin members 51, a plurality of springs 53, a plurality of washers 55, and a plurality of spring receiving members 57. The pin member 51 penetrates the flange portion 47b of the flange 47 upward in the vertical direction, is inserted into the inside of the spring 53, and is fastened to the screw hole 63 of the housing base portion 27a from below. The head portion 51c of the pin member 51 abuts on the flange portion 47b of the flange 47 from below via the washer 55. The spring 53 is provided between the brim portion 47b of the flange 47 and the housing base portion 27a, and a spring receiving member 57 is provided between the lower end portion and the brim portion 47b of each spring 53. There is. The configuration of the hand 13 is the same as that of the above-described embodiment.

With the above configuration, as shown in FIG. 15, the connecting mechanism 29C has a restoring force (tilt) that tries to return the hand 13 in a posture in which the rotation axis Ax4 is tilted with respect to the reference axis Ax5 to the posture before the tilt. Directional restoring force. An example of the first restoring force) is applied. That is, the connecting mechanism 29C transmits the elastic force of the plurality of springs 53 to the hand 13 so that the restoring force is applied to the hand 13 in the inclined posture. Further, as shown in FIG. 15, the lower edge portion of the flange portion 47b of the flange portion 47 in the inclined direction is restricted from moving downward by abutting on the washer 55. On the other hand, the upper edge portion of the brim portion 47b in the inclined direction moves upward by the abutting spring receiving member 57 rising to the position where the spring 53 is fully compressed (the position where the spring 53 is most compressed). Be regulated. As a result, the connecting mechanism 29C limits the angle range in which the hand 13 can be tilted to a predetermined angle range θ.

Although not shown, the connecting mechanism 29C has a lower side in the axial direction (an example of the other side) with respect to the hand 13 that has moved toward the upper side (an example of one side) of the rotation axis Ax4 or the reference axis Ax5 in the axial direction. ), A restoring force (axial restoring force; an example of a second restoring force) is applied. That is, the connecting mechanism 29C transmits the elastic force of the plurality of springs 53 to the hand 13 so that the restoring force is applied to the hand 13 that has moved upward in the axial direction. At this time, the flange portion 47b of the flange 47 is restricted from moving downward by abutting on the washer 55. On the other hand, the brim portion 47b is restricted from moving upward by the abutting spring receiving member 57 rising to a position where the spring 53 is fully compressed (a position where the spring 53 is most compressed). As a result, the connecting mechanism 29C limits the range in which the hand 13 can move in the axial direction to a predetermined range D.

According to this modification, the hands 13 can be rotatably and tiltably connected without providing a through hole in the housing 27 of the third arm portion 21. As a result, it is possible to prevent foreign matter from entering the robot from the outside, and it is easy to make the robot 7 explosion-proof, for example, when painting the work 3 is performed.

(4-5. When opening and closing the sliding door)
In the above embodiment, the case where the robot 7 opens and closes the rotary door 9 of the work 3 has been described, but the present invention is not limited to this, and the robot 7 may be applied to open and close the slide type door. good.

FIG. 16 shows an example of the configuration of the robot system 1 according to this modification. As shown in FIG. 16, the work 3A has a slide-type door 9A which is an opening / closing member on a side surface in the Y-axis direction. The door 9A is opened and closed mainly by moving it in the negative direction and the positive direction on the X-axis. The robot 7 moves the door 9A of the work 3A being conveyed to open in the negative direction of the X-axis, and is in an open state while a predetermined work is executed on the work 3A by another work device (not shown). The door 9A is moved in the positive direction of the X-axis to close the door 9A after the predetermined work is completed, and the opening / closing work is executed. The configuration of the robot 7 is the same as that of the above-described embodiment.

When the rotary door 9 is opened and closed as in the above-described embodiment, an external force mainly in the Y-axis direction acts on the hand 13, but when the slide door 9A is opened and closed as in this modification. On the hand 13, an external force mainly in the X-axis direction acts on the hand 13. Since the hand 13 can be tilted, it is possible to absorb external forces acting in various directions in this way. Therefore, the flexibility to the work can be improved.

(4-6. When the hand is pressed against the door to open and close it)
In the above embodiment, the case where the hand 13 is attracted to the inside of the door 9 by a magnetic force to open and close is described, but the present invention is not limited to this, and for example, the hand 13 is held and opened / closed by pressing the hand 13 against the door 9. You may.

FIG. 17 shows an example of the configuration of the robot system 1 according to this modification. As shown in FIG. 17, the robot 7 holds the door 9 by pressing the hand 13 against the end portion 9a of the door 9 from above in the vertical direction, and performs opening / closing work. Also in this case, as in the above-described embodiment, since the hand 13 can be tilted, the hand 13 is tilted so as to bend even if the workpiece 3 to be conveyed is displaced or the position / speed fluctuates. And can absorb them. Therefore, the flexibility for the work 3 can be improved. Further, since the hand 13 is connected to the tip end portion of the arm 11 so as to be movable in the axial direction along the rotation axis Ax4 or the reference axis Ax5, the hand 13 is pressed against the end portion 9a of the door 9 or opened / closed. It can absorb the impact in the vertical direction. In particular, the configuration of the above-mentioned modification (4-4) is effective because it easily absorbs the upward movement of the hand 13. Further, since the permanent magnet 35 of the hand 13 is not required, the structure of the hand 13 can be simplified and the cost can be reduced.

In the above description, when there is a description such as "vertical", "parallel", "planar", etc., the description does not have a strict meaning. That is, these "vertical", "parallel", and "planar" mean "substantially vertical", "substantially parallel", and "substantially flat", with design and manufacturing tolerances and errors allowed. ..

Further, in the above description, when there is a description such as "same", "same", "equal", "different", etc. in the external dimensions, size, shape, position, etc., the description is not a strict meaning. That is, those "same", "same", "equal", and "different" are allowed for design and manufacturing tolerances and errors, and are "substantially the same", "substantially the same", "substantially equal", and "substantially equal". It means "substantially different".

In addition to the above-mentioned above, the methods according to the above-described embodiment and each modification may be appropriately combined and used. In addition, although not illustrated one by one, the above-described embodiment and each modification are carried out with various modifications within a range that does not deviate from the purpose.

1 Robot system 7 Robot 11 Arm 13 Hand 27a Housing base (housing)
29 Coupling mechanism 29A Coupling mechanism 29B Coupling mechanism 31 Hand mechanism 31A Hand mechanism 31B Hand mechanism 35 Permanent magnet 37a Side surface 41 Support part 47 Flange (transmission member)
49 Bearing member 51 Pin member (regulatory member, fastening member)
53 Spring (elastic member)
59 Through hole 61 Tapered part 61A Tapered part 71 Spring rod (elastic member)
Ax4 Rotation axis Ax5 Reference axis D range θ Angle range

Claims (23)

With a horizontal articulated arm,
The hand provided at the tip of the arm and
A connecting mechanism that connects the hand to the tip of the arm so that the hand can rotate around a rotation axis and the rotation axis can be tilted with respect to a reference axis in a preset direction.
A robot characterized by having. The connecting mechanism is
It is characterized in that the rotation axis is configured to give a first restoring force to return to the posture before the tilt to the hand in a posture tilted with respect to the reference axis. The robot according to claim 1. The connecting mechanism is
The robot according to claim 2, wherein the hand is configured to limit the tiltable angle range to a predetermined angle range. The connecting mechanism is
It is characterized by having an elastic member and being configured to transmit the elastic force of the elastic member to the hand so that the first restoring force is applied to the hand in an inclined posture. The robot according to claim 2 or 3. The connecting mechanism is
The robot according to any one of claims 1 to 4, wherein the hand is connected to a tip end portion of the arm so as to be movable in an axial direction along the rotation axis or the reference axis. .. The connecting mechanism is
The claim is characterized in that the hand that has moved toward one side in the axial direction is configured to apply a second restoring force that tends to return toward the other side in the axial direction. The robot according to 5. The connecting mechanism is
The robot according to claim 6, wherein the hand is configured to limit a range in which the hand can move in the axial direction to a predetermined range. The connecting mechanism is
It is characterized by having an elastic member and being configured to transmit the elastic force of the elastic member to the hand so that the second restoring force is applied to the hand moved in the axial direction. The robot according to claim 6 or 7. The connecting mechanism is
Elastic members and
It has a transmission member that transmits the elastic force of the elastic member to the hand.
The elastic member is
The robot according to any one of claims 1 to 8, wherein the robot is provided between the transmission member and the housing at the tip of the arm. The connecting mechanism is
The robot according to claim 9, further comprising a bearing member rotatably supporting the hand around the rotation axis between the hand and the transmission member. The hand
It has a support portion provided so as to penetrate the housing, and has a support portion.
The bearing member is
The robot according to claim 10, wherein the support portion is rotatably supported. The transmission member is
11. The robot according to claim 11, wherein the robot is provided so as to cover at least a part of the outer periphery of the support portion, and is fitted into a through hole formed in the housing. The through hole is
The robot according to claim 12, wherein the robot has tapered portions having a tapered shape inward on both sides of the inner peripheral surface in the drilling direction. The tapered portion is
The robot according to claim 13, wherein the robot is formed in a curved surface. The connecting mechanism is
The robot according to any one of claims 9 to 14, further comprising a restricting member arranged between the transmission member and the housing and regulating the expansion / contraction direction of the elastic member. The regulating member is
The robot according to claim 15, wherein the robot is a fastening member that penetrates the transmission member, is inserted into the inside of the elastic member, and is fastened to the housing. The regulating member is
The robot according to claim 15, wherein the robot is a tubular member arranged inside the elastic member and having a bolt inserted through the transmission member and fastened to the housing inside. The connecting mechanism is
It has multiple elastic members and has multiple elastic members.
The plurality of elastic members are
The robot according to any one of claims 1 to 17, wherein the robots are arranged at a plurality of locations along the circumferential direction around the reference axis. The hand
The robot according to any one of claims 1 to 18, wherein the robot has a permanent magnet. The hand
It has a plurality of the permanent magnets and has
The plurality of permanent magnets
19. The robot according to claim 19, wherein the same magnetic poles of the adjacent permanent magnets are laminated so as to face each other along the stacking direction. The hand
The robot according to any one of claims 1 to 20, wherein the robot is a rod-shaped member extending in the longitudinal direction and has a flat side surface in contact with the work on the side perpendicular to the longitudinal direction. It is a hand mechanism provided at the tip of the horizontal articulated arm of the robot.
A hand for operating the work and
A connecting mechanism that connects the hand to the tip of the arm so that the hand can rotate around a rotation axis and the rotation axis can be tilted with respect to a reference axis in a preset direction.
A hand mechanism characterized by having. It is a robot work method that causes a robot equipped with a horizontal articulated arm to perform a predetermined work.
Bringing the hand provided at the tip of the arm into contact with the work
When the hand is moved to operate the work, the hand is rotated around a rotation axis, and the rotation axis is tilted with respect to a reference axis in a preset direction.
A robot working method characterized by having.

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