JP2015077649A - Robot origin setting method and robot - Google Patents

Abstract

PROBLEM TO BE SOLVED: To excellently perform an origin position setting of an axis member (work axis) without using an exclusive sensor.SOLUTION: A robot 1A includes: an arm 3 (second link 3b); a work axis 4 supported by the arm 3; an axis side stopper 30 provided in the work axis 4; and an arm side stopper 34 provided in the arm 3. An origin setting method for the robot 1A includes: a process for determining a position where an upper surface 30a of the stopper 30 abuts on a lower surface 34a of the stopper 34 as an axial direction origin position of the work axis 4 and determining a height position of the work axis 4 where a projection section 30b of the stopper 30 can abut on a side surface 34b of the stopper 34 with reference to the axial direction origin position; a process for setting the axial direction origin position by moving the work axis 4 and allowing the upper surface 30a to abut on the lower surface 34a; a process for disposing the work axis 4 at the height position on the basis of the axial direction origin position; and a process for setting a rotation direction origin position of the work axis 4 by rotating the work axis 4 at the height position and allowing the projection section 30b to abut on the side surface 34b of the stopper 34.

Description

  The present invention relates to a robot origin setting method and a robot including a shaft member that is driven to rotate and move up and down by a motor.

  Conventionally, a robot hand mechanism is supported on an arm (base) via a work shaft (shaft member), and the work shaft and the robot hand mechanism are integrally rotated by a driving force of a motor (hereinafter referred to as a SCARA robot). Are abbreviated as robots). Patent Document 1 discloses a method (origin finding method) for setting the origin position in the rotation direction of the work axis without using a dedicated sensor when the power is turned on. Yes. In this method, a dog (protruding portion) that protrudes upward on the robot hand mechanism side is provided in advance, while a stopper that protrudes downward on the arm side is provided, and the work shaft is rotated to move the dog and stopper in the circumferential direction. The origin position in the rotation direction is set with reference to the contact position. Such a sensorless origin setting method is useful for simplifying and reducing the cost of the robot configuration.

Japanese Patent No. 3268705

  In some robots, the robot hand mechanism not only rotates with the work axis but also moves with the work axis in the vertical direction. In such a robot, in order to set the rotation direction origin based on the above method, the work axis (robot hand mechanism) is arranged in advance at a height position where the dog and the stopper can contact in the circumferential direction. It is necessary to cause the dog and the stopper to contact each other by rotating the working shaft. In this case, considering simplification and low cost of the robot configuration, the work axis is arranged at the height position without using a dedicated sensor, as in the case of setting the origin in the rotation direction. It is preferable that the origin position in the rotation direction can be set according to the method. However, no specific method or configuration regarding this point is disclosed in Patent Document 1.

  The present invention has been made in view of such circumstances, and for a robot including a shaft member that can move and rotate in the axial direction, the origin position of the shaft member can be satisfactorily set without using a dedicated sensor. It aims at providing the technology which can be performed.

  In order to solve the above-described problems, a robot origin setting method according to the present invention includes a base member, a shaft member that performs axial movement and rotation around the base member, and the shaft member. A first axial contact portion provided in the shaft member, a second axial contact portion provided in the base member, and the shaft member so as to be able to contact each other in the axial direction with movement in the axial direction; In a state where the shaft member is arranged at a specific position in the axial direction, the first rotation direction contact portion and the base provided in the shaft member so that the shaft members can be brought into contact with each other in the rotation direction by rotating. For a robot provided with a second rotational direction contact portion provided in the member, a position where the first axial direction contact portion and the second axial contact portion contact each other is defined as an axial origin position of the shaft member. As the axial origin position in advance And setting the axial origin position by moving the shaft member and bringing the first axial contact portion and the second axial contact portion into contact with each other. An axial direction origin setting step, an axial movement step of moving the shaft member in the axial direction based on the axial direction origin position set in the axial direction origin setting step, and the specific position Rotation direction origin setting that sets the rotation direction origin position of the shaft member by rotating the shaft member disposed on the shaft and bringing the first rotation direction contact portion and the second rotation direction contact portion into contact with each other A process.

  According to this method, when the power is turned on, the shaft member is moved in the axial direction to bring the first axial contact portion and the second axial contact portion into contact with each other, whereby the axial origin position is reached. Can be specified (set). In order to rotate the shaft member after moving the shaft member to the specific position determined in advance with reference to the axial origin position, the first rotational direction contact portion and the second rotational direction The rotation direction origin position can be set by properly contacting the contact portion.

  In addition, if the axial direction origin setting step is executed in a state where the first rotational direction contact portion and the second rotational direction contact portion are at the same position in the rotational direction of the shaft member, the first axial direction contact portion and the second axial direction contact portion Before the axial contact portion comes into contact, the first rotational direction contact portion and the second rotational direction contact portion make contact in the axial direction, and as a result, the axial origin position at an incorrect position. May be set. Such inconvenience is solved by the following method.

  That is, in the origin setting method, the axial direction origin setting step moves the shaft member in the axial direction so that the first axial contact portion and the second axial contact portion approach each other. After the first temporary origin setting step for acquiring the position where the shaft member has stopped as the first temporary origin position, and after the first temporary origin setting step, the shaft member is rotated by a predetermined angle, and the first axis A second temporary origin position obtained by moving the shaft member in the axial direction so that the direction abutting portion and the second axial direction abutting portion approach each other. Temporary origin setting step and main origin setting step of setting any one of the first temporary origin position and the second temporary origin position as an axial origin position based on a predetermined setting condition Including.

  According to this method, the temporary origin positions are acquired once at positions with different rotation angles, and which of the temporary origin positions corresponds to the axial origin position in light of predetermined setting conditions. Therefore, it is possible to avoid erroneously setting a position different from the original axial origin position as the axial origin position.

  In order to avoid that a position different from the original axial origin position is erroneously set as the axial origin position, the following method may be applied.

  That is, in the axial origin setting step, the shaft member is moved in the axial direction so that the first axial contact portion and the second axial contact portion approach each other, and the shaft member stops. The process of acquiring the obtained position as the temporary origin position is executed a plurality of times while rotating the shaft member by a predetermined angle, and among the continuously acquired temporary origin positions, the predetermined number of temporary origin positions are obtained. When they are the same, the temporary origin position that is the same is set as the axial origin position.

  In short, in a structure in which the range in which the first rotation direction contact portion and the second rotation direction contact portion can contact in the axial direction (range in the rotation direction of the shaft member) is limited, a plurality of positions as described above. By acquiring the temporary origin position and checking the number of the same position, the original axial direction origin position can be specified accurately. Therefore, it is possible to avoid that a position different from the original axial origin position is erroneously set as the axial origin position.

On the other hand, the robot of the present invention is a robot including a base member and a shaft member that moves in the axial direction and rotates around the shaft center with respect to the base member, and moves the shaft member in the axial direction. Accordingly, a first axial contact portion provided in the shaft member and a second axial contact portion provided in the base member so that they can contact each other in the axial direction, and the shaft member in the axial direction. When the shaft member rotates in a state of being arranged at a specific position, the first rotation direction contact portion provided in the shaft member and the first member provided in the base member are configured to be able to contact each other in the rotation direction. A storage means for storing the specific position determined in advance with reference to a position where the first axial contact portion and the second axial contact portion contact in the axial direction; ,
Control means for controlling movement and rotation of the shaft member in the axial direction, and the control means moves the shaft member so as to move the first axial contact portion and the second axial contact portion. Axis origin setting processing for setting the axial origin position by bringing the shaft member into contact with each other, and axis movement for arranging the shaft member at the specific position based on the axial origin position set in the axial origin setting processing By rotating the shaft member disposed at the specific position and bringing the first rotation direction contact portion and the second rotation direction contact portion into contact with each other, the rotation direction origin position of the shaft member is determined. The rotation direction origin setting process to be set is executed.

  According to this configuration, when the power is turned on, the origin setting in the axial direction and the rotation direction of the shaft member can be automatically executed according to the above-described origin setting method.

  In this robot, in the axial direction origin setting process, the shaft member is moved in the axial direction so that the first axial contact portion and the second axial contact portion approach each other. After the first temporary origin setting process for acquiring the position where the motor is stopped as the first temporary origin position, and after the first temporary origin setting process, the shaft member is rotated by a predetermined predetermined angle to contact the first axial direction. Second temporary origin setting processing for acquiring a position at which the shaft member is stopped by moving the shaft member in the axial direction so that the portion and the second axial contact portion approach each other as a second temporary origin position And an origin setting process for setting one of the first temporary origin position and the second temporary origin position as an axial origin position based on a predetermined setting condition. It is suitable.

  In the axial direction origin setting process, the axial direction origin setting process moves the shaft member in the axial direction so that the first axial direction contact portion and the second axial direction contact portion approach each other. The process of moving and acquiring the position at which the shaft member has stopped as a temporary origin position is executed a plurality of times while rotating the shaft member by a predetermined angle, and the preset temporary origin position is set in advance. When the plurality of temporary origin positions are the same, the same temporary origin position may be set as the axial origin position.

  According to these configurations, during the axial origin setting process, the first rotational direction contact portion and the second rotational direction contact portion are contacted in the axial direction, and as a result, the axial direction is erroneously positioned. The inconvenience of setting the origin position can be avoided.

  In the above robot, the shaft member includes a bowl-shaped shaft side contact member in which the first axial direction contact portion and the first rotational direction contact portion are integrally provided. Is preferred.

  According to this configuration, since the first axial contact portion and the first rotational contact portion are provided on the common axial contact member, the structure of the shaft member can be simplified and the cost can be reduced. To do.

  In addition, it is preferable that the base member includes a base side contact member in which the second axial direction contact portion and the second rotational direction contact portion are integrally provided.

  According to this configuration, the second axial contact portion and the second rotational contact portion are provided on the common base-side contact member, which contributes to simplification and cost reduction of the structure of the base member. To do.

  In the robot, the shaft member has a first end and a second end, and the first axial contact portion and the second axial contact portion are included in the base member. The first rotation direction contact portion and the second rotation direction contact portion are provided on the first end portion side, and the second rotation direction contact portion is provided on the second end portion side of the base member. There may be.

  According to this configuration, in the axial origin setting process, the first rotational direction contact portion and the second rotational direction contact portion do not structurally contact in the axial direction. Contributes to speeding up of the setting process.

  In the robot, one of the first rotation direction contact portion and the second rotation direction contact portion is elastically retracted when the rotation direction contact portions contact each other in the axial direction. It may be a thing.

  According to this configuration, even when the first rotation direction contact portion and the second rotation direction contact portion contact in the axial direction during the axial direction origin setting process, one of them comes along with the contact. By retreating, the first axial contact portion and the second axial contact portion reliably contact each other. Therefore, it is possible to structurally avoid the axial origin position being set at an incorrect position by abutting the first rotational direction contact portion and the second rotational direction contact portion in the axial direction. It becomes. In addition, at the position where the first rotational direction contact portion and the second rotational direction contact portion are displaced in the rotational direction, the original position is maintained by the elastic return of the retractable rotational direction contact portion. Therefore, it is possible to perform the origin setting process in the axial direction and the rotational direction of the shaft member more quickly.

  As described above, according to the present invention, the origin position of the shaft member can be satisfactorily set without using a dedicated sensor.

1 is a side view showing a SCARA robot according to a first embodiment of the present invention. It is a perspective view which shows the front-end | tip part of an arm (2nd link). It is a block diagram which shows the control system of a scalar type robot. It is a flowchart explaining the origin setting control of the working axis by a controller. (A) is a state in which the protruding portion of the shaft side stopper is located below the arm side stopper, (b) is a state in which the protruding portion of the shaft side stopper is in contact with the lower surface of the arm side stopper, and (c) is FIG. 5 is a schematic diagram illustrating a state where the work shaft is disposed at the axial origin position (a state where the upper surface of the shaft-side stopper is in contact with the lower surface of the arm-side stopper). It is a flowchart explaining the 1st modification of the origin setting control of the working axis by a controller. It is a flowchart explaining the 2nd modification of the origin setting control of the working axis by a controller. It is a flowchart (continuation of FIG. 7) explaining the 2nd modification of the origin setting control of the working axis by a controller. It is a schematic diagram which shows the arm (2nd link) of the scalar type robot which concerns on the 2nd Embodiment of this invention. It is a flowchart explaining the origin setting control of the working axis by a controller. (A) is a state where the upper surface of the first shaft side stopper is in contact with the lower surface of the first arm side stopper, and (b) is a state where the protruding portion of the second shaft side stopper is on the upper surface of the second arm side stopper. It is a model which shows the state which contact | abutted, respectively. It is a schematic diagram which shows the arm (2nd link) of the scalar type robot which concerns on the 3rd Embodiment of this invention. It is a flowchart explaining the origin setting control of the working axis by a controller. (A) shows a state in which the protruding portion of the shaft side stopper is in contact with the lower surface of the arm side stopper, and (b) shows that the protruding portion of the shaft side stopper moves outward from the position of the arm side stopper as the work shaft rotates. It is a schematic diagram which each shows the state which escaped. It is a schematic diagram which shows the modification of the scalar type robot which concerns on 3rd Embodiment.

  Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

(First embodiment)
FIG. 1 is a schematic side view of a SCARA robot according to a first embodiment of the present invention. A SCARA robot 1A (hereinafter abbreviated as “robot 1A”) shown in FIG. 1 includes a columnar arm support 2 installed on a base, an arm 3 connected to the arm support 2, and the arm 3 And a work shaft 4 (corresponding to the shaft member of the present invention) supported by the front end portion. Reference numeral 5 in FIG. 1 denotes a cylindrical guide member that accommodates electric power of a motor 12, 20, and 22 described later, a cable for transmitting a control signal, and the like, and a second link between the arm support 2 and the arm 3. 3b.

  The arm 3 includes a first link 3a that is supported by the arm support 2 and extends in the horizontal direction, and a second link 3b that is supported at the tip of the first link 3a and extends in the horizontal direction.

  The first link 3a is supported on the upper portion of the arm support 2 so as to be rotatable (turnable) around a vertical axis. The first link 3 a is connected to a first arm motor 10 disposed inside the arm support 2 via a speed reduction mechanism (not shown), and is driven to rotate by the first arm motor 10.

  The second link 3b is supported on the top end of the first link 3a so as to be rotatable (turnable) around a vertical axis. The second link 3b is connected to a second arm motor 12 mounted on the second link 3b via a speed reduction mechanism (not shown), and is rotationally driven by the second arm motor 12.

  The working shaft 4 is a spline shaft. The work shaft 4 extends in the vertical direction (axis) with respect to the second link 3b in a state of penetrating the second link 3b in the vertical direction at the tip of the second link 3b (corresponding to the base member of the present invention). Direction) and rotation about the axis is supported, and is driven by the R-axis motor 20 and the Z-axis motor 22.

  More specifically, a pulley 14 having a spline nut (not shown) fitted therein is rotatably supported at the tip of the second link 3b. A relay pulley 16 that is integrally provided with an upper pulley 16a and a lower pulley 16b is rotatably supported at a position near the pulley 14 in the second link 3b. An R-axis motor 20 is mounted on the second link 3b, and a transmission belt 19 is mounted across the pulley 18 fixed to the output shaft of the R-axis motor 20 and the lower pulley 16b of the relay pulley 16. A transmission belt 17 is mounted across the upper pulley 16 a of the relay pulley 16 and the pulley 14. With this configuration, the work shaft 4 is rotationally driven by the R-axis motor 20.

  In addition, a ball screw shaft 24 that extends in the vertical direction and is rotatably supported by the second link 3b is provided at a side position of the work shaft 4 in the second link 3b. A nut member 26 is screwed onto the ball screw shaft 24, and the nut member 26 is assembled to a head holder 28 that rotatably holds the upper end of the work shaft 4. A Z-axis motor 22 is mounted on the second link 3b, and spans a pulley (not shown) fixed to the output shaft of the Z-axis motor 22 and a pulley (not shown) fixed to the lower end of the ball screw shaft 40. A transmission belt 23 is attached. That is, when the ball screw shaft 24 is rotationally driven by the Z-axis motor 22 via the transmission belt 23 or the like, the work shaft 4 and the head holder 28 are moved together with the second link 3b (spline nut) along with the rotation of the ball screw shaft 24. ) Up and down.

  A hook-shaped shaft-side stopper 30 (corresponding to the shaft-side abutting member of the present invention) is fixed to the work shaft 4, and an arm is located near the work shaft 4 on the lower surface of the second link 3 b. A side stopper 34 (corresponding to the base side contact member of the present invention) is fixed. These shaft-side stopper 30 and arm-side stopper 34 set the origin position in the axial direction (vertical direction) and rotational direction of the work shaft 4 with respect to the second link 3b (arm 3) when the power of the robot 1A is turned on. It is a member for doing.

  As shown in FIGS. 1 and 2, the shaft-side stopper 30 is an annular member with flat upper and lower surfaces, and is fixed to a position near the tip (lower end) of the work shaft 4. The shaft-side stopper 30 has a substantially cylindrical protrusion 30b (first of the present invention) at a position on the upper surface 30a (corresponding to the first axial contact portion of the present invention) and radially outward. Corresponding to the rotation direction abutting portion). In this example, when the bolt is screwed into the upper surface 30a of the shaft side stopper 30, the projection 30b is formed by the bolt head.

  On the other hand, the arm-side stopper 34 is a block-shaped member formed in a substantially fan shape so as to follow the outer peripheral surface of the work shaft 4. The arm-side stopper 34 includes a flat lower surface 34a (corresponding to the second axial contact portion of the present invention) with which the upper surface 30a of the shaft-side stopper 30 can abut, and a vertical extending in the radial direction of the work shaft 4. It has a side surface 34b (corresponding to the second rotational direction contact portion of the present invention) which is a side surface and can contact the protrusion 30b of the shaft side stopper 30 as the work shaft 4 rotates.

  That is, in this robot 1A, the position where the upper surface 30a of the shaft side stopper 30 abuts against the lower surface 34a of the arm side stopper 34 is the axial origin position of the work shaft 4, and the side surface 34b of the arm side stopper 34 is On the other hand, the position where the protrusion 30b of the shaft side stopper 30 abuts is the origin position in the rotation direction of the work shaft 4.

  The arm-side stopper 34 is substantially fan-shaped as described above, but its central angle θ is 180 degrees from the state in which the protrusion 30b of the shaft-side stopper 30 is in contact with the lower surface 34a of the arm-side stopper 34. The protrusion 30b is always set to escape to the outside of the arm side stopper 34 (outside in the rotation direction of the work shaft 4) when rotated. In this example, the central angle θ of the arm side stopper 34 is set to about 30 °.

  In addition, the work shaft 4 has a work device mounting region on the tip side of the shaft side stopper 30, and a work device such as a robot arm is fixed in this region.

  The robot 1A includes an arm controller 50 as shown in FIG. The arm controller 50 (hereinafter abbreviated as “controller 50”) comprehensively controls the operation of the entire arm 3 including the work shaft 4. The controller 50 includes a known CPU, ROM, RAM, and the like, and includes a main control unit 52, a storage unit 54, a motor driver 56, and the like as its functional configuration.

  The storage unit 54 stores a program and data for controlling the entire robot 1A, and the main control unit 52 outputs a control signal to the motor driver 56 based on the program or the like, whereby the motor driver The motors 11, 12, 20 and 22 are controlled via 56. Respective resolvers 11a, 12a, 20a, and 22a are provided in the motors 11, 12, 20, and 22, respectively, and rotation angle information detected by the resolvers 11a, 12a, 20a, and 22a is fed back to the main controller 52. The In the present embodiment, the main control unit 52 and the motor driver 56 correspond to the control unit of the present invention, and the storage unit 54 corresponds to the storage unit of the present invention.

  The robot 1A is not provided with a dedicated sensor for setting the origin of the work axis 4. When the power is turned on, the main control is performed in accordance with a program stored in the storage unit 54. Based on the control of the unit 52, the origin position of the work shaft 4 is set.

  Hereinafter, the origin position setting control in the axial direction and the rotational direction of the work shaft 4 by the controller 50 will be described with reference to the flowchart of FIG.

  The control shown in this flowchart starts when the power of the robot 1A is turned on. When this control is started, the arm controller 50 raises the work shaft 4 to a position where it naturally stops in a state where the rotation angle position is maintained (steps S1 and S3). Specifically, the work shaft 4 is raised to a position where the work shaft 4 stops when the shaft side stopper 30 of the work shaft 4 and the arm side stopper 34 of the second link 3b (arm 3) abut against each other in the vertical direction. In this case, the controller 50 (main control unit 52) detects whether or not the work shaft 4 has stopped from the amount of change in the rotation angle information input from the resolver 22a. That is, when the rise of the work shaft 4 is stopped as described above, the change amount of the rotation angle information input from the resolver 22a is substantially “0”, and accordingly, the work shaft 4 is stopped. It becomes possible to detect. In this case, it may be detected whether the work shaft 4 is stopped based on a change in the current value supplied from the motor driver to the Z-axis motor 22.

  When it is determined that the work shaft 4 has stopped, the controller 50 determines the stop position of the work shaft 4 in the vertical direction (axial direction) based on the rotation angle information input from the resolvers 22a and 22b with reference to when the power is turned on. 4 is acquired (stored) as the first temporary axis direction origin position (Z1), and the rotation angle position of the work shaft 4 at this time is acquired as the first rotation angle position (R1) of the work shaft 4 (step S5).

  Next, the controller 50 lowers the work shaft 4 by a predetermined amount (for example, 10 mm) stored in advance, and further rotates the work shaft 4 by 180 ° in a specific direction (in this example, counterclockwise when viewed from below). After that, the work shaft 4 is raised (steps S7 to S11). Then, similarly to the process of step S3, it is determined whether or not the work shaft 4 has stopped (step S13).

  If it is determined that the work shaft 4 has stopped, the controller 50 acquires the stop position in the vertical direction as the second temporary axis direction origin position (Z2) of the work shaft 4, and the rotation angle position of the work shaft 4 at this time Is obtained as the second rotation angle position (R2) of the work shaft 4 (step S15).

  Next, the controller 50 compares the first temporary axis direction origin position (Z1) acquired in step S5 with the second temporary axis direction origin position (Z2). Here, if Z1> Z2, that is, if the first temporary axis direction origin position (Z1) is higher than the second temporary axis direction origin position (Z2), the controller 50 slightly moves the work axis 4 The work shaft 4 is returned to the first temporary rotation direction origin position (R1) by lowering and rotating the work shaft 4 (step S19).

  Thereafter, the controller 50 sets the first temporary axis direction origin position (Z1) as the axial direction origin position (Z) and sets a predetermined rotational direction origin based on the first temporary axis direction origin position (Z1). As the work shaft 4 rotates, the protrusion 30b of the shaft-side stopper 30 is moved to a height position where it can be brought into contact with the side surface 34b of the arm-side stopper 34 (step S21). The storage unit 54 stores data indicating a rotation direction origin set height position (corresponding to a set position of the present invention) determined based on the original axial direction origin position. In the processing, the controller 50 moves the work axis 4 based on the data with the axial direction origin position (Z) set this time, that is, the first temporary axis direction origin position (Z1) as a reference.

  The controller 50 then continues until the rotation of the work shaft 4 stops, that is, until the work shaft 4 stops at a position where the projection 30b of the shaft-side stopper 30 abuts against the side surface 34b of the arm-side stopper 34. When the work shaft 4 is determined to have stopped, the stop position of the work shaft 4 in the rotation direction is set as the rotation direction origin position (R) of the work shaft 4 (steps S23 to S27). This is the end of this flowchart. In step S25, as in step S3, the controller 50 detects whether the work shaft 4 has stopped based on the amount of change in the rotation angle information input from the resolver 20a.

  On the other hand, if it is determined in step S17 that Z1 <Z2, that is, if the second temporary axis direction origin position (Z2) is higher than the first temporary axis direction origin position (Z1), the controller 50 sets the second temporary axis direction origin position (Z2) as the axial direction origin position (Z), and sets the second temporary axis direction origin position (Z2) as a reference to a predetermined rotational direction origin set height position. After moving the work shaft 4 (step S29), the process proceeds to step S23, and the processing direction of steps S23 to S27 is executed to set the rotation direction origin of the work shaft 4.

  If it is determined in step S17 that Z1 = Z2, that is, if the heights of the first temporary axis direction origin position (Z1) and the second temporary axis direction origin position (Z2) are equal, the controller 50 shifts the process to step S21 and sets the rotation direction origin of the work shaft 4 by executing the processes of steps 21 to S27 as described above.

  That is, in the robot 1A, as described above, the position where the upper surface 30a of the shaft-side stopper 30 contacts the lower surface 34a of the arm-side stopper 34 is the axial origin position (Z) of the work shaft 4. However, because the protrusion 30b is provided on the shaft-side stopper 30, if the working shaft 4 is simply moved in the axial direction when the power is turned on, as shown in FIG. 5A, the protrusion is directly below the arm-side stopper 34. If there is a portion 30b, the projection 30b of the shaft-side stopper 30 comes into contact with the lower surface 34a of the arm-side stopper 34 as shown in FIG. ) May be set. Therefore, in this example, in steps S5 and S15, the work shaft 4 is raised at a position where the rotation angle positions are 180 ° different from each other, and the stop position is set to the first temporary axis direction origin position (Z1) and the second temporary axis direction origin. It is acquired as the position (Z2), and by comparing these positions, it is determined which position is the true origin position in the axial direction of the work shaft 4. Specifically, when the projection 30b of the shaft-side stopper 30 is in contact with the arm-side stopper 34 (lower surface 34a), the position of the work shaft 4 is the original axial direction by the height of the projection 30b. It becomes lower than the origin position (FIG. 5C). Accordingly, in the process of step S17, the higher one of the first temporary axis direction origin position (Z1) and the second temporary axis direction origin position (Z2) is set as the axial direction origin position (Z). However, the upper surface 30a of the shaft-side stopper 30 may abut against the lower surface 34a of the arm-side stopper 34 even if the rotation angle positions are 180 ° different from each other. The axial direction origin position (Z1) is set as the rotational axis direction origin position (Z).

  As described above, in this robot 1A, the position where the upper surface 30a of the shaft side stopper 30 contacts the lower surface 34a of the arm side stopper 34 is the axial origin position (Z) of the work shaft 4, and the arm side The position where the protrusion 30b of the shaft side stopper 30 abuts against the side surface 34b of the stopper 34 is the rotation direction origin position (R) of the work shaft 4. When the power is turned on, as described above, the work shaft 4 is moved in the vertical direction (axial direction) so that the upper surface 30a of the shaft-side stopper 30 and the lower surface 34a of the arm-side stopper 34 are brought into contact with each other. 4 is set to the axial direction origin position (Z), and further moved to the rotational direction origin set height position based on this axial direction origin position (Z), and then the work shaft 4 is rotated to rotate the arm side stopper 34. The rotation direction origin position (R) of the work shaft 4 is set by bringing the protrusion 30b of the shaft side stopper 30 into contact with the (side surface 34b). Therefore, the axial direction of the work shaft 4 and the origin position in the rotational direction can be appropriately set only by the rotational angle information from the resolvers 20a and 22a provided in the motors 20a and 22a without using a dedicated sensor.

  In particular, in this robot 1A, because the protrusion 30b protrudes from the upper surface 30a of the shaft-side stopper 30, simply moving the work shaft 4 in the axial direction when the power is turned on causes the lower surface 34a of the arm-side stopper 34 to move. The protrusion 30b of the shaft side stopper 30 may come into contact. However, according to the robot 1A, as described above, when the work shaft 4 is rotated 180 ° from the state in which the protrusion 30b of the shaft-side stopper 30 is in contact with the lower surface 34a of the arm-side stopper 34, as described above, The arm side stopper 34 and the like are formed so that the protrusion 30b escapes to the outside of the arm side stopper 34 (outside in the rotation direction). Then, the work shaft 4 is raised at a position where the rotation angle positions are 180 ° different from each other, and the stop positions are acquired as the first temporary axis direction origin position (Z1) and the second temporary axis direction origin position (Z2). The axial origin position is set by comparing these positions. Therefore, it is possible to accurately set the axial origin position (Z) and the rotational origin position (R) of the work shaft 4 while having the structure of the shaft side stopper 30 as described above.

  In this embodiment, as described above, data indicating the rotation direction origin set height position determined with reference to the original axial direction origin position is stored in the storage unit 54 in advance. The step of determining the set height position and storing it in the storage unit 54 corresponds to the preparation step of the present invention. 4 corresponds to the axial origin setting process (axial origin setting process) of the present invention, and the processes of steps S21 and S29 are the axial movement process (axial movement process) of the present invention. Steps S25 to S27 correspond to a rotation direction origin setting step (rotation direction origin setting process). Of the processes of steps S1 to S21 and S29, steps S1 to S5 correspond to the first temporary origin setting step (first temporary origin setting process) of the present invention, and steps S7 to S15 are the second temporary origin of the present invention. This corresponds to the origin setting process (second temporary origin setting process), and steps S17 to S21 and S29 correspond to the origin setting process (original origin setting process) of the present invention. The conditions for setting the axial origin position in the processes of steps S17, S21 and S29 correspond to the setting conditions of the present invention.

<First Modification>
Next, a first modification of the origin position setting control in the axial direction and the rotational direction of the work shaft 4 by the controller 50 will be described with reference to the flowchart of FIG.

  As a premise of this control, the central angle θ of the arm side stopper 34 is determined by rotating the work shaft 4 by 30 ° from a state in which the protrusion 30b of the shaft side stopper 30 is in contact with the lower surface 34a of the arm side stopper 34. The protrusion 30b is always set so as to be able to escape to the outside (in the rotational direction) of the arm side stopper 34.

  In the control shown in FIG. 6, first, the processes of steps S31 to S45 that are equivalent to the processes of steps S1 to S15 of the flowchart of FIG. 4 are executed, whereby the controller 50 determines the first temporary axis direction origin position (Z1). The second temporary axis direction origin position (Z2) is acquired. However, in the process of step S39 (corresponding to the process of step S9 in FIG. 4), the controller 50 rotates the work shaft 4 by 30 °. Therefore, unlike the example of FIG. 4, the rotation angle of the work shaft 4 when the first temporary axis direction origin position (Z1) is acquired and the second temporary axis direction origin position (Z2) are acquired. The difference in the rotation angle of the work shaft 4 is 30 °.

  When the second temporary axis direction origin position (Z2) of the work shaft 4 and the rotation angle position (R2) of the work shaft 4 at this time are acquired, the controller 50 determines whether or not Z1 = Z2 (step S47). ). If YES is determined here, processing in steps S51 to S57 equivalent to the processing in steps S21 to S27 in the flowchart of FIG. 4 is executed. That is, the controller 50 sets the first temporary axis direction origin position (Z1) as the axial direction origin position (Z) and stores it in the storage unit 54 with reference to the first temporary axis direction origin position (Z1). The work shaft 4 is moved to the rotation direction origin set height position that has been set (step S51). Then, the work shaft 4 is rotated to a position where the projecting portion 30b of the shaft-side stopper 30 hits the side surface 34b of the arm-side stopper 34 and the work shaft 4 stops, and the stop position of the work shaft 4 is set to the rotation direction origin position (R ) (Steps S53 to S57). Thereby, this flowchart is complete | finished.

  On the other hand, when it is determined NO in the process of step S47, the controller 50 discards the current first temporary axis direction origin position (Z1) and the current second temporary axis direction origin position (Z2). Is replaced with the first temporary axis direction origin position (Z1) (step S59), and the process proceeds to step S37. Then, the processes in steps S37 to S47 are repeated, and if YES is finally determined in step S47, the process proceeds to step S51.

  That is, in the control of the first modification, the axial direction origin position is acquired while shifting the rotation angle position of the work shaft 4 by 30 °, and the previously acquired temporary axis direction origin position of the work axis 4 is set as the first temporary axis. The first temporary axis direction origin position (Z1) and the second temporary axis direction origin position are set as the second temporary axis direction origin position (Z2), which is the direction origin position (Z1) and the temporary axis direction origin position of the work axis 4 acquired thereafter. When the position (Z2) becomes the same, the first temporary axis direction origin position (Z1) is set as the axial direction origin position (Z) of the work shaft 4. As described above, when the work shaft 4 is rotated 30 ° from the state in which the protrusion 30b of the shaft-side stopper 30 is in contact with the lower surface 34a of the arm-side stopper 34, the protrusion 30b is always in contact with the arm-side stopper. The arm-side stopper 34 is formed so that it can escape to the outside (rotation direction outside) of 34, and the first and second provisional axial direction origin positions (Z1, Z2) acquired successively become the same. In short, any temporary axis direction origin position (Z1, Z2) means a state in which the upper surface 30a of the shaft side stopper 30 is in contact with the lower surface 34a of the arm side stopper 34. That is, it means that the work shaft 4 is in a state of being arranged at the original axial origin position. Therefore, when the first temporary axis direction origin position (Z1) and the second temporary axis direction origin position (Z2) are the same as described above, the first temporary axis direction origin position (Z1) is set as the work axis 4. By setting as the axial origin position (Z), the axial origin position (Z) can be accurately set.

  In the example of FIG. 6, in the process of step S51, the first temporary axis direction origin position (Z1) is set to the axial direction origin position (Z). Of course, the second temporary axis direction origin position (Z2) is set. ) May be set to the axial origin position (Z).

  In this embodiment, the processes of steps S31 to S51 and S59 in FIG. 6 correspond to the axial direction origin setting process (axial direction origin setting process) of the present invention, and the process of step S51 is the axis movement process of the present invention. This corresponds to (axis movement processing), and the processing in steps S53 to S57 corresponds to a rotation direction origin setting step (rotation direction origin setting processing).

<Second Modification>
Next, a second modification of the origin position setting control in the axial direction and the rotational direction of the work shaft 4 by the controller 50 will be described with reference to the flowcharts of FIGS.

  In the control shown in FIGS. 7 and 8, first, the controller 50 sets “1” to the counter n (step S61), and then executes the processes of steps S63 to S77. The processing in steps S63 to S77 is substantially the same as the processing in steps S31 to S45 in the flowchart of FIG. 6, whereby the controller 50 allows the nth provisional axis direction origin position (Zn) and the n + 1th provisional axis. The direction origin position (Z (n + 1)) and rotation angle positions Rn, R (n + 1) are acquired.

Next, the controller 50 determines whether or not Zn = Z (n + 1) (step S79). If YES is determined in this step, the processes of steps S81 to S87 are executed. This process corresponds to steps S51 to S57 in FIG. That is, the controller 50 moves the work shaft 4 to the rotation direction origin set height position stored in the storage unit 54 with reference to the n _max provisional axis direction origin position (Z _max ). Then, the work shaft 4 is rotated to a position where the projecting portion 30b of the shaft side stopper 30 abuts against the side surface 34b of the arm side stopper 34 and the work shaft 4 stops, and the stop position of the work shaft 4 is set to the rotation direction origin position ( R).

   On the other hand, if NO is determined in the process of step S79, the controller 50 executes the processes of steps S89 to S97 to thereby obtain the (n + 2) provisional axis direction origin position (Z (n + 2)). Get more. The processes in steps S89 to S97 are equivalent to the processes in steps S69 to S77. Of the already acquired n-th provisional axis direction origin position (Zn) and n + 1th provisional axis direction origin position (Z (n + 1)), the larger value and the (n + 2) provisional axis direction origin position ( Z (n + 2)) is determined to be the same (step S99), and if determined to be the same here, the controller 50 moves the process to step S81 and returns to the rotation direction origin position of the work shaft 4 ( A process for setting R) is executed.

  On the other hand, if it is determined NO in the process of step S99, the controller 50 increments the counter n by “1” (step S100), moves the process to step S89, and repeats the processes of steps S89 to S99. Finally, of the nth provisional axis direction origin position (Zn) and the (n + 1) th provisional axis direction origin position (Z (n + 1)), the larger value and the (n + 2) provisional axis direction origin position (Z If (n + 2)) becomes the same, the process proceeds to step S81, and a process for setting the rotation direction origin position of the work shaft 4 is executed.

That is, in the first modified example of FIG. 6 described above, the temporary axis direction origin position is acquired at different rotational angle positions while shifting the rotational angle position of the work shaft 4 by 30 °, and the temporary axis acquired continuously. When the direction origin position becomes the same, the provisional axial direction origin position acquired previously is set as the axial direction origin position (R). On the other hand, the second modified example of FIG. 7 acquires the temporary axis direction origin position at different rotation angle positions while shifting the rotation angle position of the work shaft 4 by 30 °. when two of the temporary axial home position but became the same, than is the axial home position (R) the first n _max temporary axial origin position (Z _max) obtained from the later.

  The reason for the control of the second modification is the same as that of the control of the first modification, and the axial origin position (Z) can be set accurately as in the case of the first modification.

In the example of FIGS. 7 and 8, the n _max provisional axial direction origin position (Z _max ) is set to the axial origin position (Z) in the process of step S81. The temporary axis direction origin position may be set to the axial direction origin position (Z).

  In this embodiment, the processes of steps S61 to S81 and steps S89 to S100 of FIGS. 7 and 9 correspond to the axial origin setting process (axial origin setting process) of the present invention, and the process of step S81 is performed. This corresponds to the axis movement process (axis movement process) of the present invention, and the processes in steps S83 to S87 correspond to the rotation direction origin setting process (rotation direction origin setting process).

(Second Embodiment)
FIG. 9 is a schematic diagram showing an arm (second link) portion of the SCARA robot according to the second embodiment of the present invention. The hardware configuration of the SCARA robot 1B according to the second embodiment (hereinafter abbreviated as “robot 1B”) is basically the same as that of the robot 1A of the first embodiment except for the points described below. It is.

  In the robot 1B of the second embodiment, the shaft side stopper 30 is fixed at a position near the lower end of the work shaft 4 (corresponding to the first end portion of the present invention), and the corresponding arm side stopper 34 is the second link. It is common to the robot 1A of the first embodiment in that it is fixed to the lower surface of 3b. However, in the robot 1 </ b> B of the second embodiment, a hook-shaped shaft side stopper 31 (referred to as the second shaft side stopper 31) different from the shaft side stopper 30 (referred to as the first shaft side stopper 30) is provided on the work shaft 4. The arm side stopper 35 (referred to as the second arm side stopper 35) corresponding to the upper end (corresponding to the second end portion of the present invention) is fixed to the upper surface of the second link 3b.

  The first shaft side stopper 30 (corresponding to the first axial contact portion of the present invention) and the first arm side stopper 34 (corresponding to the second axial direction contact portion of the present invention) are the first shaft side stopper. 30 is substantially the same as the shaft-side stopper 30 and the arm-side stopper 34 of the first embodiment except that the protrusion 30b is not provided on the shaft 30. On the other hand, the second arm side stopper 35 (corresponding to the second rotational direction abutting portion of the present invention) is a shaft-like body standing on the upper surface of the second link 3b and in the vicinity of the work shaft 4. . Also, the second shaft side stopper 31 (corresponding to the first rotational direction contact portion of the present invention) is located on the lower surface of the second shaft side stopper 31 in the radially outer side with the rotation of the work shaft 4, and the second arm side stopper 31. The protrusion part 31a which can be contact | abutted to the side surface of 35 is provided.

  In the robot 1B, the position where the upper surface 30a of the first shaft-side stopper 30 and the lower surface 34a of the first arm-side stopper 34 abut is set as the axial origin position of the work shaft 4, and the second shaft-side stopper 31 The position where the protruding portion 31 a contacts the side surface of the second arm side stopper 35 is the rotation direction origin position of the work shaft 4.

  Next, the origin position setting control in the axial direction and the rotational direction of the work shaft 4 by the controller 50 of the robot 1B of the second embodiment will be described with reference to the flowchart of FIG.

  When this control is started, the controller 50 raises the work shaft 4 to a position where the work shaft 4 is naturally stopped while maintaining the rotation angle position (steps S101 and S103). Then, when the work shaft 4 stops, the stop position is set as the axial origin position (Z) of the work shaft 4 (step S105). That is, the first axis-side stopper 30 is not provided with a projection for setting the rotational direction origin, and when the work shaft 4 is raised, the first arm-side stopper 34 is always provided as shown in FIG. The upper surface 30a of the first shaft side stopper 30 abuts against the lower surface 34a. Accordingly, the stop position of the work shaft 4 can be immediately set as the axial origin position (Z).

  Next, the controller 50 moves (lowers) the work shaft 4 toward the rotational direction origin set height position stored in the main controller 52 with reference to the axial direction origin position (Z) set in step S105. Is started (step S107). Then, it is determined whether or not the work shaft 4 has stopped before reaching the height position (step S109).

  If YES is determined, the controller 50 rotates the work shaft 4 by a predetermined rotation angle and then further lowers the work shaft 4 (step S111). It is determined whether or not the set height position has been reached (step S113). That is, depending on the positional relationship between the protruding portion 31a of the second shaft side stopper 31 and the second arm side stopper 35, as shown in FIG. In some cases, the protruding portion 31a of the 31 abuts and the work shaft 4 is not disposed at the origin setting height position. Therefore, in this case (YES in step S109), the work shaft 4 is rotated so that the protruding portion 31a of the second shaft side stopper 31 escapes in the rotation direction with respect to the second arm side stopper 35. Therefore, the rotation angle of the work shaft 4 in step S111 is set to an angle that can surely escape the protruding portion 31a in contact with the second arm side stopper 35. The controller 50 performs the determination in step S113 based on the rotation direction origin set height position and the amount of change in the rotation angle information input from the resolver 22a.

  When it is determined in step S113 that the work shaft 4 has reached the origin setting height position, the controller 50 causes the projecting portion 31a of the second shaft side stopper 31 to abut against the side surface of the second arm side stopper 35 and the work shaft. The work shaft 4 is rotated to a position at which 4 stops, and the stop position is set as the rotation direction origin position (R) of the work shaft 4 (steps S115 to S119), and then this flowchart is ended.

  On the other hand, if NO is determined in the process of step S109, that is, if the work axis 4 has reached the origin setting height position, the controller 50 skips the processes of steps S111 and S113 and proceeds to the process of step S115. Transition. Thereby, the work shaft 4 is rotated to set the rotation direction origin position (R).

  According to the robot 1B of the second embodiment as described above, as in the robot 1A of the first embodiment, a dedicated sensor is used to set the origin position in the axial direction and the rotational direction of the work shaft 4 when the power is turned on. It becomes possible to carry out appropriately without using. In particular, in the case of the robot 1B, when the work shaft 4 is raised, the upper surface 30a of the first shaft-side stopper 30 is always in contact with the lower surface 34a of the first arm-side stopper 34. The position (Z) can be set quickly.

  In this embodiment, the processing of steps S101 to S107 in FIG. 10 corresponds to the axial origin setting step (axial origin setting processing) of the present invention, and the processing of steps S107 to S113 is the axial movement step of the present invention. This corresponds to (axis movement processing), and the processing in steps S115 to S119 corresponds to a rotation direction origin setting step (rotation direction origin setting processing).

(Third embodiment)
FIG. 12 is a schematic diagram showing an arm (second link) portion of a SCARA robot according to the third embodiment of the present invention. The hardware configuration of the SCARA robot 1C according to the third embodiment (hereinafter abbreviated as “robot 1C”) is basically the same as that of the robot 1A of the first embodiment except for the points described below. It is.

  In the robot 1 </ b> C of the third embodiment, the protrusion 30 b is configured to be elastically retractable in the shaft-side stopper 30. Specifically, after the protrusion 30b is supported so as to be able to protrude and retract over a protruding position where it protrudes upward from the upper surface 30a of the shaft side stopper 30 and a retracted position where it retracts below the upper surface 30a, the compression coil spring It is urged | biased by the protrusion position by elastic members, such as. In this respect, the robot 1C is different in configuration from the robot 1A of the first embodiment.

  Next, the origin position setting control in the axial direction and the rotational direction of the work shaft 4 by the controller 50 of the robot 1C according to the third embodiment will be described with reference to the flowchart of FIG.

  When this control is started, the controller 50 raises the work shaft 4 to a position where the work shaft 4 is naturally stopped while maintaining the rotation angle position (steps S121 and S123). Then, when the work shaft 4 stops, the stop position is set as the axial origin position (Z) of the work shaft 4 (step S125). In this robot 1C, as described above, the protrusion 30b of the shaft-side stopper 30 can be elastically retracted, and even if the protrusion 30b is positioned below the arm-side stopper 34, as shown in FIG. As shown, the protrusion 30b is pushed down to the retracted position as it contacts the lower surface 34a of the arm side stopper 34. Therefore, when the work shaft 4 is raised, the upper surface 30a of the shaft-side stopper 30 always comes into contact with the lower surface 34a of the arm-side stopper 34. Therefore, the stop position of the work shaft 4 is immediately set to the axial origin position ( Z) can be set.

  Next, the controller 50 moves the work shaft 4 to the rotational direction origin setting height position stored in the storage unit 54 with reference to the axial direction origin position (Z) set in step S125, and then moves the arm side. The work shaft 4 is rotated to a position where the projecting portion 31a of the shaft-side stopper 30 abuts against the side surface of the stopper 34 and the work shaft 4 stops. Accordingly, the stop position is set as the rotation direction origin position (R) of the work shaft 4 (steps S127 to S133). In this robot 1C, as shown in FIG. 14A, the work shaft 4 is rotated by the process of step S129 even if the protrusion 30b is in contact with the lower surface 34a of the arm side stopper 34 and is pushed down to the retracted position. When the position of the protrusion 30b is shifted in the rotational direction from the lower surface 34a of the arm-side stopper 34, the protrusion 30b is elastically returned from the retracted position to the protruding position as shown in FIG. Therefore, by rotating the work shaft 4, the protruding portion 30 b of the shaft side stopper 30 can always be brought into contact with the side surface 34 b of the arm side stopper 34.

  As described above, the robot 1C according to the third embodiment as described above is similar to the robots 1A and 1B according to the first and second embodiments in the axial direction and the rotation direction of the work shaft 4 when the power is turned on. The origin position can be appropriately set without using a dedicated sensor.

  In particular, according to the robot 1C of the third embodiment, as in the robot 1A of the first embodiment, two or more provisional axis direction origin positions are acquired and the true axis direction origin position is specified. As in the robot 1B of the second embodiment, when the work shaft 4 is moved to the rotation direction origin set height position, a process of rotating the work shaft 4 once is not generated. Therefore, as compared with the robots 1A and 1B of the first and second embodiments, there is an advantage that the origin position setting in the axial direction and the rotational direction of the work shaft 4 can be performed in a shorter time.

  In this embodiment, the processing of steps S121 to S125 in FIG. 10 corresponds to the axial origin setting step (axial origin setting processing) of the present invention, and the processing of step S127 is the axial movement step (axis) of the present invention. The processing in steps S129 to S133 corresponds to a rotation direction origin setting step (rotation direction origin setting process).

  About this 3rd Embodiment, it is also possible to employ | adopt a structure as shown in FIG. 15 as the modification. In the configuration shown in the figure, a projecting portion 34c (corresponding to the second rotational direction abutting portion of the present invention) is provided on the arm side stopper 34 side, and this projecting portion 34c is a side surface of the shaft side stopper 30 ( (Corresponding to the first rotation contact portion of the present invention). Even with such a configuration, it is possible to receive the same operational effects as the configuration of FIG.

  By the way, the above-described SCARA robots 1A to 1C according to the first to third embodiments and the origin setting control (origin setting method) of the work axis 4 by these SCARA robots 1A to 1C are the robot according to the present invention and It is an illustration of a preferred embodiment of the origin setting method, and the specific configuration and the specific origin setting method of the SCARA robots 1A to 1C can be appropriately changed without departing from the gist of the present invention.

  In particular, the specific shapes and arrangements of the shaft-side stoppers 30 and 31, the arm-side stoppers 34 and 35, the protrusions 30b, and the like are not necessarily limited to those of the above-described embodiment, and the axial direction of the work shaft 4 When the origin position in the rotation direction is set, it can be appropriately changed as long as the movement and rotation of the work shaft 4 with respect to the second link 3b (arm 3) can be restricted.

  Moreover, although each embodiment demonstrated the example which applied this invention to what is called a SCARA type | mold robot, this invention is a working axis | shaft (shaft member) which performs the movement of an axial direction with respect to a base member, and the rotation of a shaft center. Of course, the present invention can be applied to robots other than SCARA robots.

1A, 1B, 1C SCARA robot 2 Arm support 3 Arm 3a 1st link 3b 2nd link 4 Work shaft 30 Axis side stopper 30a Upper surface 30b Projection part 34 Arm side stopper 34a Lower surface 34b Side surface 50 Arm controller 52 Main control part 54 Storage unit 56 Motor driver

Claims (10)

A base member, a shaft member that performs axial movement with respect to the base member and rotation around the shaft center, and the shaft so that the shaft member can abut against each other in the axial direction as the shaft member moves in the axial direction. The first axial contact portion provided in the member, the second axial contact portion provided in the base member, and the shaft member rotating in a state where the shaft member is disposed at a specific position in the axial direction. With respect to the robot including the first rotation direction contact portion provided in the shaft member and the second rotation direction contact portion provided in the base member so as to be able to contact each other in the rotation direction. A preparatory step of predetermining the specific position based on the axial origin position in advance, with the position where the first axial contact part and the second axial contact part are in contact as the axial origin position of the shaft member;
An axial origin setting step of setting the axial origin position by moving the shaft member and bringing the first axial contact portion and the second axial contact portion into contact with each other;
Based on the axial origin position set in the axial origin setting step, the axial movement step of moving the shaft member in the axial direction and disposing it at the specific position;
Rotation that sets the rotation direction origin position of the shaft member by rotating the shaft member arranged at the specific position and bringing the first rotation direction contact portion and the second rotation direction contact portion into contact with each other. A robot origin setting method comprising: a direction origin setting step. In the robot origin setting method according to claim 1,
In the axial direction origin setting step, the shaft member is moved in the axial direction so that the first axial contact portion and the second axial contact portion approach each other, and the axial member is stopped. A first provisional origin setting step for obtaining the first provisional origin position,
After the first temporary origin setting step, the shaft member is rotated by a predetermined angle, and the shaft member is moved to the shaft so that the first axial contact portion and the second axial contact portion approach each other. A second temporary origin setting step of acquiring the position where the shaft member is stopped as the second temporary origin position by moving in the direction;
A main origin setting step of setting one of the first temporary origin position and the second temporary origin position as an axial origin position based on a predetermined setting condition. Characteristic robot origin setting method. In the robot origin setting method according to claim 1,
In the axial origin setting step, a position where the shaft member is stopped by moving the shaft member in the axial direction so that the first axial contact portion and the second axial contact portion approach each other. Is acquired as a temporary origin position by executing the shaft member a plurality of times while rotating the shaft member by a predetermined angle. The robot origin setting method is characterized in that the same provisional origin position is set as the axial origin position. A robot comprising a base member and a shaft member that performs axial movement and rotation around the axis with respect to the base member,
A first axial contact portion provided on the shaft member and a second axial contact portion provided on the base member so that the axial members can contact each other in the axial direction as the shaft member moves in the axial direction; ,
A first rotation direction contact portion provided in the shaft member so that the shaft member can be brought into contact with each other in the rotation direction by rotating the shaft member in a state where the shaft member is disposed at a specific position in the axial direction. And a second rotation direction contact portion provided in the base member,
Storage means for storing the specific position determined in advance on the basis of a position where the first axial contact portion and the second axial contact portion contact in the axial direction;
Control means for controlling movement and rotation of the shaft member in the axial direction,
The control means moves the shaft member and sets the axial origin position by setting the axial origin position by bringing the first axial contact portion and the second axial contact portion into contact with each other. Based on the axial origin position set in the axial origin setting process, the shaft movement process for arranging the shaft member at the specific position, and the first rotational direction by rotating the shaft member arranged at the specific position And a rotation direction origin setting process for setting a rotation direction origin position of the shaft member by bringing the contact part into contact with the second rotation direction contact part. The robot according to claim 4, wherein
The axial origin setting process is
The shaft member is moved in the axial direction so that the first axial contact portion and the second axial contact portion approach each other, and the position where the shaft member stops is acquired as the first temporary origin position. First temporary origin setting process to
After the first temporary origin setting process, the shaft member is rotated by a predetermined angle, and the shaft member is moved to the shaft so that the first axial contact portion and the second axial contact portion approach each other. A second temporary origin setting process for acquiring a position at which the shaft member is stopped by moving in the direction as a second temporary origin position;
A main origin setting process for setting one of the first temporary origin position and the second temporary origin position as an axial origin position based on a predetermined setting condition. Characteristic robot. The robot according to claim 4, wherein
In the axial origin setting process, the shaft member is moved in the axial direction so that the first axial contact portion and the second axial contact portion approach each other, and the axial member is stopped. Is acquired as a temporary origin position by executing the shaft member a plurality of times while rotating the shaft member by a predetermined angle. When this happens, the same temporary origin position is set as the axial origin position. The robot according to any one of claims 4 to 6,
The robot according to claim 1, wherein the shaft member includes a bowl-shaped shaft side contact member in which the first axial direction contact portion and the first rotational direction contact portion are integrally provided. The robot according to any one of claims 4 to 7,
The robot according to claim 1, wherein the base member includes a base side contact member in which the second axial direction contact portion and the second rotational direction contact portion are integrally provided. The robot according to claim 4, wherein
The shaft member has a first end and a second end,
The first axial contact portion and the second axial contact portion are provided on the first end portion side of the base member,
The robot according to claim 1, wherein the first rotation direction contact portion and the second rotation direction contact portion are provided on the second end side of the base member. The robot according to claim 4, wherein
One of the first rotational direction contact portion and the second rotational direction contact portion is elastically retracted when the rotational direction contact portions contact each other in the axial direction. robot.

Images