WO2014126112A1

WO2014126112A1 - Industrial robot and industrial robot control method

Info

Publication number: WO2014126112A1
Application number: PCT/JP2014/053214
Authority: WO
Inventors: 矢澤　隆之; 慎浩田中; 淳尾辻; 洋和渡邊; 淳之介小山
Original assignee: 日本電産サンキョー株式会社
Priority date: 2013-02-13
Filing date: 2014-02-12
Publication date: 2014-08-21
Also published as: CN104995001B; JPWO2014126112A1; CN104995001A; TW201440974A; JP6295243B2; PH12015501728B1; PH12015501728A1; TWI647078B

Abstract

In this robot (1), the torque for rotating motors (15, 17, 19) in one direction is defined as positive torque and the torque for rotating the same in the other direction as negative torque. During test operation of a robot (1) performed after completing teaching, a control unit (5) rotates the motors (15, 17, 19) at a speed lower than the speed during normal operation of the robot (1) performed after completion of test operation, and if during test operation, the motors (15, 17, 19) rotate in the first direction, then the motors (15, 17, 19) are controlled at a torque limiting value lower than the torque limiting value in the case of the motors (15, 17, 19) rotating in the one direction during normal operation, and if during test operation, the motors (15, 17, 19) rotate in the other direction, then the motors (15, 17, 19) are controlled at a torque limiting value higher than the torque limiting value in the case of the motors (15, 17, 19) rotating in the other direction during normal operation.

Description

Industrial robot and control method for industrial robot

The present invention relates to an industrial robot and an industrial robot control method.

Conventionally, a horizontal articulated robot used in a part assembly line or the like is known (for example, see Patent Document 1). The robot described in Patent Document 1 is capable of rotating to a support arm, a first arm rotatably connected to the support arm, a second arm rotatably connected to the first arm, and a second arm. And a third arm that can be moved up and down with respect to the second arm. The robot also includes a motor for rotating the first arm relative to the support arm, a motor for rotating the second arm relative to the first arm, and a third arm relative to the second arm. And a motor for raising and lowering the third arm relative to the second arm. In this robot, when teaching (teaching) the robot, the four motors are rotated at a low speed and the current limit value of the motor is reduced to prevent the robot from colliding with peripheral devices during teaching. .

JP-A-63-68390

In the robot described in Patent Document 1, automatic operation is performed when teaching is completed. However, if the robot is not properly taught and the robot is automatically operated, the robot may come into contact with the peripheral devices of the robot and the robot may be damaged.

In a horizontal articulated robot such as the robot described in Patent Document 1, an end effector is attached to the third arm. Further, the end effector may hold a predetermined workpiece. Therefore, the absolute value of the torque required for the motor (lifting motor) that raises and lowers the third arm when raising the third arm is increased due to the weight of the third arm, end effector, work, etc. When the third arm is lowered, the absolute value of the torque required for the lifting motor is reduced.

Generally, in order to prevent damage to the end effector and the like when the end effector contacts the peripheral device or the like, a torque limit value is set for the lift motor, and when the torque of the lift motor reaches the torque limit value, The lifting motor is stopped. Also, the absolute value of the torque limit value of the lifting motor when raising the third arm and the absolute value of the torque limit value of the lifting motor when lowering the third arm are generally set to the same value. Yes.

For example, assuming that the torque of the lifting motor in the direction to raise the third arm is positive torque and the torque of the lifting motor in the direction to lower the third arm is negative torque, the third arm is The absolute value of the torque required for the lifting motor that rotates in one direction when raising is increased, and the absolute value of the torque required for the lifting motor that rotates in the other direction when lowering the third arm is small. Therefore, if the absolute value of the torque limit value is set according to the torque of the lifting motor when raising the third arm, the end effector etc. will contact the peripheral device etc. when the third arm is lowered. Nevertheless, the lifting motor continues to rotate without the torque of the lifting motor falling below the torque limit value, and the end effector and the like may be damaged. On the other hand, if the absolute value of the torque limit value is set according to the torque of the lifting motor when the third arm is lowered, the third arm is normally raised when the third arm is raised. Regardless, the elevator motor torque may exceed the torque limit value and the elevator motor may stop.

Therefore, a first problem of the present invention is to provide an industrial robot capable of preventing damage during automatic operation after completion of teaching. A first object of the present invention is to provide an industrial robot control method capable of preventing damage during automatic driving after completion of teaching.

The second problem of the present invention is that the maximum value of the absolute value of torque required when rotating in one direction is larger than the maximum value of the absolute value of torque required when rotating in the other direction. An industrial robot provided with a motor for operation is to provide an industrial robot capable of preventing damage to the industrial robot and peripheral devices and capable of appropriate operation. The second problem of the present invention is that the maximum value of the absolute value of torque required when rotating in one direction is larger than the maximum value of the absolute value of torque required when rotating in the other direction. In a method for controlling an industrial robot provided with a motor for operation, the industrial robot control method capable of preventing damage to the industrial robot and peripheral devices and capable of appropriately operating the industrial robot. Is to provide.

In order to solve the first problem, an industrial robot of the present invention (first invention) is an industrial robot including an operation motor and a control unit that controls the motor. The torque of the motor for rotating is set to a positive torque, the torque of the motor for rotating the motor in the other direction is set to a negative torque, and the teaching point and / or the industrial robot is controlled after the teaching of the industrial robot is finished If the automatic operation of the industrial robot performed to check whether the program is correct is the test operation, and the automatic operation of the industrial robot performed after the test operation is the normal operation, the control unit performs the normal operation during the test operation. If the motor rotates at a lower rotational speed than the normal rotational speed, and if the motor rotates in one direction during the test operation, If the motor is controlled with a torque limit value that is lower than the torque limit value when the motor rotates in one direction, and the motor rotates in the other direction during test operation, the motor rotates in the other direction during normal operation. In this case, the motor is controlled with a torque limit value higher than the torque limit value.

In order to solve the first problem, an industrial robot control method according to the present invention (first invention) is an industrial robot control method including a motor for operation, and the motor is unidirectional. The torque of the motor for rotating the motor to the positive direction is set to a positive torque, the torque of the motor for rotating the motor to the other direction is set to a negative torque, and after the teaching of the industrial robot is finished, the teaching point and / or the industrial robot If the automatic operation of the industrial robot that is performed to check whether the control program is correct is the test operation, and the automatic operation of the industrial robot that is performed after the test operation is the normal operation, the rotation during the test operation is the normal operation. If the motor rotates at a lower rotational speed than the speed and the motor rotates in one direction during test operation, the motor If the motor is controlled with a torque limit value lower than the torque limit value when rotating in the direction and the motor rotates in the other direction during test operation, the torque when the motor rotates in the other direction during normal operation The motor is controlled with a torque limit value higher than the limit value.

In the present invention, at the time of test operation which is automatic operation performed to confirm whether the teaching point and / or the control program is correct after completion of teaching, the rotation speed is lower than the rotation speed at the time of normal operation performed after the completion of the test operation. The motor is rotating at speed. That is, in the present invention, the operation speed of the industrial robot during the test operation is slow. Therefore, according to the present invention, it is possible to reduce the free running distance of the industrial robot when the operator senses the danger during the test operation and makes the industrial robot emergency stop.

In the present invention, when the motor rotates in one direction during the test operation, the motor is controlled with a torque limit value lower than the torque limit value when the motor rotates in one direction during the normal operation, and the test operation is performed. Sometimes, when the motor rotates in the other direction, the motor is controlled with a torque limit value higher than the torque limit value when the motor rotates in the other direction during normal operation. Therefore, in the present invention, when the industrial robot comes into contact with the peripheral device or the like during the test operation, the motor torque exceeds the torque limit value or falls below the torque limit value in a short time. Therefore, according to the present invention, when the motor torque exceeds the torque limit value or falls below the torque limit value, the motor is immediately stopped so that the industrial robot comes into contact with the peripheral device or the like during the test operation. The motor can be stopped in a short time.

As described above, according to the present invention, it is possible to reduce the free running distance of the industrial robot when the operator detects a danger during the test operation and makes an emergency stop of the industrial robot. When the industrial robot comes into contact with a peripheral device or the like, the motor can be stopped in a short time. Therefore, according to the present invention, it is possible to prevent the industrial robot from being damaged during the test operation. Also, if a problem occurs during a test operation, the industrial robot can be prevented from coming into contact with peripheral devices during normal operation after completion of the test operation by taking predetermined measures such as teaching again. It becomes possible to prevent the industrial robot from being damaged during normal operation. As a result, according to the present invention, it is possible to prevent the industrial robot from being damaged during the automatic operation after completion of teaching.

In the present invention, the industrial robot includes a motor for raising and lowering the end effector as a motor, and the torque limit value of the elevator motor when the end effector is raised during the test operation is the first torque limit value. Assuming that the torque limit value of the elevating motor when the end effector descends is the second torque limit value, the control unit makes the absolute value of the second torque limit value smaller than the absolute value of the first torque limit value. As described above, the first torque limit value and the second torque limit value are set, and when the end effector is raised during the test operation, the control unit controls the lifting motor based on the first torque limit value to perform the test. When the end effector is lowered during operation, it is preferable to control the lifting motor based on the second torque limit value.

Generally, the absolute value of the torque required for the lifting motor when raising the end effector increases due to the effects of the end effector and the weight of the work held by the end effector. Although the absolute value of the torque required for the motor is small, with this configuration, the first torque limit value and the second torque limit value are set so that the absolute value of the second torque limit value is smaller than the absolute value of the first torque limit value. Since the second torque limit value is set, when the end effector is rising normally, the torque of the lifting motor exceeds, for example, the first torque limit value, and the lifting motor does not stop, and When the end effector or the like comes into contact with the peripheral device or the like, the end effector is set so that the torque of the elevating motor exceeds, for example, the first torque limit value. To set a first torque limit value is possible in accordance with the torque required of the elevating motor when increasing the connector. Also, when the end effector is descending normally, the lifting motor torque is, for example, lower than the second torque limit value so that the lifting motor does not stop, and the end effector contacts the peripheral device, etc. In such a case, the second torque limit value can be set according to the torque required for the lift motor when the end effector is lowered so that the torque of the lift motor is lower than the second torque limit value, for example. Become. Further, with this configuration, the lifting motor is controlled based on the first torque limit value when the end effector is raised, and the lifting motor is controlled based on the second torque limit value when the end effector is lowered. When the end effector moves up and down, the end effector, etc. comes into contact with peripheral devices, etc., and if the torque of the lifting motor exceeds or falls below the torque limit value, the lifting motor is stopped to prevent damage to the end effector, etc. It becomes possible to do. Further, when the end effector is normally raised and lowered, the end effector can be appropriately raised and lowered by continuing to rotate the raising and lowering motor.

In the present invention, the industrial robot includes a pendant switch electrically connected to the control unit, and the motor load including at least one of the weight of the end effector and the weight of the work held by the end effector is pendant. It is possible to input from the switch, and the control unit preferably sets the first torque limit value and the second torque limit value based on the motor load input from the pendant switch. With this configuration, the end effector can be lifted and lowered more appropriately, and when the end effector or the like comes into contact with a peripheral device or the like, the torque of the lift motor can surely exceed or fall below the torque limit value. As described above, the first torque limit value and the second torque limit value can be set according to the motor load. Therefore, the end effector can be raised and lowered more appropriately, and damage to the end effector and the like can be reliably prevented.

In the present invention, the industrial robot includes, for example, a main body portion, a first arm portion whose base end side is rotatably connected to the main body portion, and a base end side rotatable to the distal end side of the first arm portion. A second arm portion coupled to the first arm portion and an end effector disposed on the distal end side of the second arm portion, and as a motor for operation, a second arm portion for rotating the first arm portion with respect to the main body portion. A first rotation motor, a second rotation motor for rotating the second arm portion relative to the first arm portion, a rotation motor for rotating the end effector relative to the second arm portion, A lifting motor for lifting and lowering the end effector with respect to the two arm portions is provided.

In the present invention, the industrial robot includes a main body portion, a first arm portion whose base end side is rotatably connected to the main body portion, and a base end side rotatably connected to the distal end side of the first arm portion. A second arm portion, an end effector disposed on the distal end side of the second arm portion, a first rotating motor for rotating the first arm portion relative to the main body portion, and a first arm portion The second arm is provided with a second rotation motor for rotating the second arm portion and a rotation motor for rotating the end effector with respect to the second arm portion. The controller includes a lifting motor for moving the end effector up and down with respect to the unit, and the control unit sets the first rotation motor, the second rotation motor, and the rotation motor to the same rotational speed as in the normal operation during the test operation. Rotate at speed, or In addition to controlling with the torque limit value that is the same as the torque limit value during normal operation, the elevating motor is rotated in one direction during the test operation by rotating the elevating motor at a lower rotational speed than during normal operation. , The elevator motor is controlled with a torque limit value lower than the torque limit value when the elevator motor rotates in one direction during normal operation, and the elevator motor moves in the other direction during test operation. When rotating, it is preferable to control the lifting motor with a torque limit value higher than the torque limiting value when the lifting motor rotates in the other direction during normal operation.

Due to the weight of the end effector and the work held by the end effector, if the end effector when lowered comes into contact with the peripheral device, etc., the end effector etc. is likely to be damaged. It is possible to stop the elevating motor for elevating in a short time when the end effector etc. comes into contact with the peripheral device etc. during the test operation, and the operation of the end effector after the elevating motor is stopped The amount can be reduced. Accordingly, it is possible to prevent damage to the end effector and the like during the test operation. Also, with this configuration, the first rotation motor, the second rotation motor, and the rotation motor rotate at the same speed as the rotation speed during the normal operation during the test operation. The operating speed can be increased.

In the present invention, it is preferable that the controller can select the motor rotation speed and the torque limit value during the test operation. If comprised in this way, it will become possible to perform the test driving | operation of an industrial robot with various combinations of the rotational speed of a motor, and a torque limit value.

In order to solve the second problem, the industrial robot of the present invention (second invention) includes an operation motor and a control unit that controls the motor, and the motor rotates in one direction. Sometimes the maximum absolute value of the torque required for the motor is larger than the maximum absolute value of the torque required for the motor when the motor rotates in the other direction. If the torque limit value of the motor is the first torque limit value and the torque limit value of the motor when rotating in the other direction is the second torque limit value, the control unit sets the absolute value of the second torque limit value to the first torque limit value. The first torque limit value and the second torque limit value are set so as to be smaller than the absolute value of the torque limit value, and the control unit is based on the first torque limit value when the motor rotates in one direction. Control the motor, the motor is the other When rotating in, and controlling the motor based on the second torque limit value.

In order to solve the second problem, an industrial robot control method according to the present invention (second invention) is an industrial robot control method including an operation motor, and the motor is unidirectional. The maximum absolute value of the torque required for the motor when rotating in the direction is larger than the maximum absolute value of the torque required for the motor when rotating in the other direction. When the torque limit value of the motor when rotating is the first torque limit value and the torque limit value of the motor when rotating in the other direction is the second torque limit value, the absolute value of the second torque limit value is the first torque. The first torque limit value and the second torque limit value are set so as to be smaller than the absolute value of the limit value. When the motor rotates in one direction, the motor is controlled based on the first torque limit value. And the other motor When rotating in, and controlling the motor based on the second torque limit value.

In the present invention, the maximum absolute value of torque required for the motor when the motor rotates in one direction is greater than the maximum absolute value of torque required for the motor when the motor rotates in the other direction. It is getting bigger. In the present invention, the absolute value of the second torque limit value that is the torque limit value of the motor when rotating in the other direction is equal to the first torque limit value that is the torque limit value of the motor when rotating in one direction. The first torque limit value and the second torque limit value are set so as to be smaller than the absolute value. Therefore, in the present invention, the torque of the motor when the motor rotates in one direction and the industrial robot is operating normally, for example, exceeds the first torque limit value, and the motor does not stop, and When the motor rotates in one direction, the motor torque when a part of the industrial robot comes into contact with the peripheral device etc., for example, exceeds the first torque limit value. It is possible to set the first torque limit value according to the torque required for. In addition, the motor torque when the motor rotates in the other direction and the industrial robot is operating normally is, for example, less than the second torque limit value, and the motor does not stop. When the motor is rotated in the other direction, for example, the motor torque when a part of the industrial robot comes into contact with the peripheral device or the like while rotating to the lower side is less than the second torque limit value. The second torque limit value can be set according to the torque.

In the present invention, when the motor rotates in one direction, the motor is controlled based on the first torque limit value, and when the motor rotates in the other direction, the motor is controlled based on the second torque limit value. is doing. Therefore, in the present invention, when the motor rotates and the industrial robot operates, a part of the industrial robot comes into contact with the peripheral device and the motor torque exceeds or falls below the torque limit value. In addition, the motor can be stopped to prevent damage to industrial robots and peripheral devices. In the present invention, when the motor rotates and the industrial robot is operating normally, the industrial robot can be operated appropriately by continuing to rotate the motor.

In the industrial robot of the present invention, for example, the industrial robot is disposed in the atmosphere, the motor is a lifting motor for lifting the end effector, and the end effector is raised when the motor rotates in one direction. When the motor rotates in the other direction, the end effector descends, the first torque limit value is the motor torque limit value when raising the end effector, and the second torque limit value descends the end effector. The control unit controls the motor based on the first torque limit value when the end effector is raised, and moves up and down based on the second torque limit value when the end effector is lowered. The motor is controlled.

In the industrial robot control method of the present invention, for example, the industrial robot is disposed in the atmosphere, the motor is a lifting motor for lifting the end effector, and the motor rotates in one direction. When the end effector is raised and the motor rotates in the other direction, the end effector is lowered. The first torque limit value is the torque limit value of the motor when the end effector is raised, and the second torque limit value is The torque limit value of the motor when the end effector is lowered, the motor is controlled based on the first torque limit value when the end effector is raised, and is raised or lowered based on the second torque limit value when the end effector is lowered. The motor is controlled.

In this case, when the end effector is rising normally, the torque of the motor exceeds, for example, the first torque limit value so that the motor does not stop, and the end effector etc. has contacted the peripheral device etc. In this case, for example, the first torque limit value can be set according to the torque required for the motor when the end effector is raised so that the torque of the motor exceeds the first torque limit value. In addition, when the end effector is descending normally, the motor torque is, for example, below the second torque limit value so that the motor does not stop, and the end effector etc. comes into contact with the peripheral device etc. For example, the second torque limit value can be set in accordance with the torque required of the motor when the end effector is lowered, so that the torque is lower than the second torque limit value. In this case, when the end effector is raised, the lifting motor is controlled based on the first torque limit value, and when the end effector is lowered, the lifting motor is controlled based on the second torque limit value. Therefore, if the end effector etc. comes into contact with peripheral devices etc. when the end effector moves up and down and the motor torque exceeds or falls below the torque limit value, the motor can be stopped to prevent damage to the end effector etc. It becomes possible. Further, when the end effector is normally raised and lowered, the end effector can be appropriately raised and lowered by continuing to rotate the motor.

In the present invention, the industrial robot includes a pendant switch electrically connected to the control unit, and the motor load including at least one of the weight of the end effector and the weight of the work held by the end effector is pendant. It is possible to input from the switch, and the control unit preferably sets the first torque limit value and the second torque limit value based on the motor load input from the pendant switch. With this configuration, the end effector can be raised and lowered more appropriately, and when the end effector or the like comes into contact with a peripheral device or the like, the torque of the motor surely exceeds or falls below the torque limit value. As described above, the first torque limit value and the second torque limit value can be set according to the motor load. Therefore, the end effector can be raised and lowered more appropriately, and damage to the end effector and the like can be reliably prevented.

In the present invention, the controller preferably drives the motor to acquire the motor load of the motor, and sets the first torque limit value and the second torque limit value based on the acquired motor load. With this configuration, the torque of the motor can surely exceed the torque limit value when the industrial robot can be operated more appropriately and when a part of the industrial robot comes into contact with a peripheral device or the like. The first torque limit value and the second torque limit value can be set in accordance with the motor load so as to be lower. Therefore, the industrial robot can be operated more appropriately, and damage to the industrial robot and peripheral devices can be surely prevented.

In the present invention, for example, the control unit stores the first torque limit value and the second torque limit value according to the motor load as a table, and the control unit corresponds to the first torque corresponding to the motor load. The limit value and the second torque limit value are read and set.

In the present invention, the control unit controls the motor based on the first torque limit value at least when the end effector is raised when teaching the industrial robot, and is controlled when the end effector is lowered when teaching the industrial robot. It is preferable to control the motor based on the two torque limit value. When teaching an industrial robot to be operated by an operator's manual operation, the end effector may come into contact with peripheral devices, etc., and damage the end effector compared to when the industrial robot is automatically operated after the teaching is completed. Is expensive. Therefore, if comprised in this way, even if it is at the time of teaching, it will become possible to prevent damage to an end effector etc.

In the present invention, the control unit controls the motor based on the first torque limit value when the end effector is raised during the automatic operation of the industrial robot after the teaching is finished, and the first control unit controls the motor when the end effector is lowered during the automatic operation. The motor is controlled based on the two torque limit values, and the first torque limit value during teaching is different from the first torque limit value during automatic operation. The second torque limit value during teaching and the automatic operation are different. It is preferable that the second torque limit value at the time is different. With this configuration, the first torque limit value and the second torque limit value during automatic operation can be set so that the motor rotation speed during automatic operation is faster than the motor rotation speed during teaching. become. Therefore, it is possible to increase the lifting speed of the end effector during automatic operation.

In the present invention, for example, an industrial robot includes an end effector mounting member to which an end effector is mounted, and a motor moves the end effector and the end effector mounting member up and down.

In the present invention, for example, an industrial robot includes an end effector, an end effector mounting member to which the end effector is mounted, a shaft member that is arranged with the vertical direction as an axial direction, and the end effector mounting member is fixed to the upper end, and a shaft member A case body in which at least a lower end side is accommodated, and a bellows arranged at one end to be fixed to the case body and the other end to the shaft member so as to cover the outer peripheral side of the shaft member. The end effector, the end effector mounting member, and the lifting / lowering motor for moving the shaft member up and down. The end effector and the end effector mounting member are arranged in a vacuum and are either on the inner peripheral side or the outer peripheral side of the bellows. One is in a vacuum and the other of the inner and outer peripheral sides of the bellows is the atmosphere The end effector is lowered when the motor rotates in one direction, the end effector is raised when the motor rotates in the other direction, and the first torque limit value is the motor when the end effector is lowered. The second torque limit value is a torque limit value of the motor when raising the end effector, and the control unit controls the motor based on the first torque limit value when the end effector is lowered. Then, when the end effector is lifted, the lifting motor is controlled based on the second torque limit value.

In this case, the end effector and the end effector mounting member are disposed in a vacuum, and when the shaft member is lowered together with the end effector and the end effector mounting member and the bellows is extended, negative pressure is generated and the end effector is generated. Therefore, the absolute value of the torque required for the motor when lowering the end effector is large, and the absolute value of the torque required for the motor when raising the end effector is small. May be. However, even in this case, when the end effector is descending normally, the torque of the motor is, for example, below the first torque limit value so that the motor does not stop, and the end effector or the like is connected to the peripheral device. For example, the first torque limit value can be set according to the torque required for the motor when the end effector is lowered so that the torque of the motor is lower than the first torque limit value, for example. . In addition, when the end effector is rising normally, the motor torque exceeds, for example, the second torque limit value, and the motor does not stop and the end effector etc. comes into contact with the peripheral device etc. For example, the second torque limit value can be set in accordance with the torque required of the motor when the end effector is raised so that the torque exceeds the second torque limit value. In this case, when the end effector is lowered, the lifting motor is controlled based on the first torque limit value, and when the end effector is lifted, the lifting motor is controlled based on the second torque limit value. Therefore, if the end effector or the like comes into contact with a peripheral device or the like when the end effector moves up and down and the motor torque exceeds or falls below the torque limit value, the motor can be stopped to prevent damage to the end effector or the like. It becomes possible. Further, when the end effector is normally raised and lowered, the end effector can be appropriately raised and lowered by continuing to rotate the motor.

In the present invention, for example, the industrial robot is a battery exchange robot provided with a battery insertion / removal mechanism that is attached to a vehicle and that pulls out the battery from the battery housing portion in which the battery is housed and inserts the battery into the battery housing portion. The battery insertion / removal mechanism includes a battery engaging portion that engages with the battery, and the motor is a pull-in / out motor for moving the battery engaging portion, and the battery is rotated when the motor rotates in one direction. The engaging part inserts the battery into the battery accommodating part, and when the motor rotates in the other direction, the battery engaging part pulls out the battery from the battery accommodating part, and the battery engaging part accommodates the battery in the first torque limit value. This is the torque limit value of the motor when The torque limit value is a torque limit value of the motor when the battery engaging portion pulls out the battery from the battery housing portion, and the control unit controls the motor based on the first torque limit value when the battery is inserted, and the battery At the time of drawing, the lifting motor is controlled based on the second torque limit value.

In this case, the motor engaging torque when the battery engaging portion normally performs the battery insertion operation exceeds the first torque limit value, for example, and the battery engaging portion does not stop. The first torque limit value may be set according to the torque required for the motor when the battery is inserted so that the torque of the motor exceeds, for example, the first torque limit value when the motor contacts the peripheral device. It becomes possible. In addition, the motor torque when the battery engaging portion is normally performing the battery pulling operation is, for example, less than the second torque limit value, and the motor does not stop. For example, the second torque limit value can be set according to the torque required for the motor when the battery is pulled out so that the torque of the motor falls below, for example, the second torque limit value when contacting the device. . In this case, the motor is controlled based on the first torque limit value when the battery is inserted, and the lifting motor is controlled based on the second torque limit value when the battery is pulled out. When the battery engaging portion or the like comes into contact with a peripheral device or the like at the time of replacement and the motor torque exceeds or falls below the torque limit value, damage to the battery engaging portion or the like can be prevented. In addition, when the battery engaging portion is operating normally at the time of battery replacement, it is possible to keep the motor rotating and operate the battery engaging portion appropriately.

As described above, according to the present invention (first invention), it is possible to prevent the industrial robot from being damaged during automatic operation after the completion of teaching. Further, according to the present invention (second invention), it is possible to prevent the industrial robot and peripheral devices from being damaged, and it is possible to appropriately operate the industrial robot.

It is a side view for demonstrating the structure of the industrial robot concerning embodiment of this invention. It is a graph for demonstrating the torque limit value of the motor for 1st rotation shown in FIG. It is a graph for demonstrating the torque limit value of the motor for raising / lowering shown in FIG. It is a table | surface for demonstrating an example of the table of the torque limitation value memorize | stored in the control part shown in FIG. It is a graph for demonstrating the torque limit value of the motor for raising / lowering shown in FIG. It is a table | surface for demonstrating an example of the table of the torque limitation value memorize | stored in the control part shown in FIG. It is a top view of the industrial robot concerning other embodiment of this invention. It is a side view which shows an industrial robot from the EE direction of FIG. It is a side view of the industrial robot concerning other embodiment of this invention. It is a top view for demonstrating the raising / lowering mechanism of the industrial robot shown in FIG. It is a figure of the industrial robot concerning other embodiment of this invention, (A) is a top view, (B) is a side view. It is sectional drawing for demonstrating the internal structure of the F section of FIG. 11 (B). It is a perspective view of the battery exchange system in which the industrial robot concerning other embodiment of this invention is installed. It is a perspective view which shows the G section of FIG. 13 from another angle. It is the schematic for demonstrating the structure of the battery shown in FIG. 13, and a battery accommodating part. It is a figure which shows the battery insertion / extraction mechanism and lifting mechanism shown in FIG. 14 from the front. It is a figure which shows a battery insertion / extraction mechanism and a raising / lowering mechanism from the HH direction of FIG. It is a figure for demonstrating the battery moving mechanism shown in FIG. 16 from a side surface. It is a perspective view of the industrial robot concerning other embodiment of this invention. It is a perspective view of the industrial robot concerning other embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[Configuration Common to Embodiments 1 and 2]
(Composition of industrial robot)
FIG. 1 is a side view for explaining the configuration of an industrial robot 1 according to an embodiment of the present invention. In the following description, the Z direction in FIG. The Z1 direction side is the “upper” side, and the Z2 direction side is the “lower” side.

The industrial robot 1 (hereinafter referred to as “robot 1”) of this embodiment is a horizontal articulated robot (SCARA robot) that is installed and used in a part production line, an assembly line, or the like, and is disposed in the atmosphere. Has been. The robot 1 includes a main body 2, an arm 3 whose base end side is rotatably connected to the main body 2, and a ball screw spline 4 attached to the distal end side of the arm 3. An end effector (not shown) is attached to the ball screw spline 4. The robot 1 includes a control unit 5 that controls the robot 1 and a pendant switch 6 that is electrically connected to the control unit 5.

The main body 2 is formed in a substantially cylindrical shape. The lower end of the main body 2 is fixed to a frame 7 that forms a part of a production line or an assembly line, for example. The arm 3 is composed of two arm parts, a first arm part 11 and a second arm part 12 disposed on the upper side of the first arm part 11. The proximal end side of the first arm portion 11 is rotatably connected to the main body portion 2, and the proximal end side of the second arm portion 12 is rotatably connected to the distal end side of the first arm portion 11. .

The joint that connects the main body 2 and the first arm 11 receives the motor 15 as a first rotation motor for rotating the first arm 11 with respect to the main body 2 and the power of the motor 15. A decelerator 16 that decelerates and transmits is disposed. The motor 15 is a servo motor. Specifically, the motor 15 is an AC servo motor. The output shaft of the motor 15 is fixed to the input portion of the speed reducer 16, and the proximal end side of the first arm portion 11 is fixed to the output portion of the speed reducer 16. The body of the motor 15 is fixed to the case body of the speed reducer 16. The case body of the speed reducer 16 is fixed to the main body 2.

The joint portion connecting the first arm portion 11 and the second arm portion 12 includes a motor 17 as a second rotation motor for rotating the second arm portion 12 with respect to the first arm portion 11, and a motor. A speed reducer 18 that decelerates and transmits the power of 17 is disposed. The motor 17 is a servo motor. Specifically, the motor 17 is an AC servo motor. The output shaft of the motor 17 is fixed to the input portion of the speed reducer 18, and the distal end side of the first arm portion 11 is fixed to the output portion of the speed reducer 18. The body of the motor 17 is fixed to the case body of the speed reducer 18. The case body of the speed reducer 18 is fixed to the base end side of the second arm portion 12.

A motor 19 as a rotation motor for rotating the end effector with respect to the second arm portion 12 and a speed reducer 20 that reduces and transmits the power of the motor 19 are attached to the second arm portion 12. Yes. The motor 19 is a servo motor. Specifically, the motor 19 is an AC servo motor. The output shaft of the motor 19 is fixed to the input portion of the speed reducer 20, and the pulley 21 is fixed to the output portion of the speed reducer 20. The body of the motor 19 is fixed to the case body of the speed reducer 20. The case body of the speed reducer 20 is fixed to the upper surface of the second arm portion 12.

Further, the above-described ball screw spline 4 and a motor 22 as a lifting motor for lifting the end effector with respect to the second arm portion 12 are attached to the second arm portion 12. The ball screw spline 4 includes a ball screw spline shaft 23 arranged with the vertical direction as an axial direction, a ball screw nut 24 for moving the ball screw spline shaft 23 in the vertical direction, and a ball screw spline shaft 23 centering on the axis of the ball screw spline shaft 23. And a spline nut 25 to be rotated. The motor 22 is a servo motor. Specifically, the motor 22 is an AC servo motor. A pulley 28 is fixed to the output shaft of the motor 22. A pulley 29 is attached to the ball screw nut 24. A belt 30 is stretched between the pulley 28 and the pulley 29. A pulley 31 is attached to the spline nut 25. A belt 32 is stretched between the pulley 21 and the pulley 31.

The ball screw nut 24 and the spline nut 25 are rotatably held by a holding member 33 formed in a substantially cylindrical shape. A plate is fixed to the upper end of the holding member 33, and the main body of the motor 22 is fixed to the plate. The lower end of the holding member 33 is fixed to the upper surface of the second arm portion 12. An end effector is attached to the lower end of the ball screw spline shaft 23. That is, an end effector is attached to the distal end side of the second arm portion 12. The ball screw spline shaft 23 of the present embodiment is an end effector attachment member to which an end effector is attached.

Further, a bellows fixing member 35 to which the lower end of the bellows 34 is fixed is attached to the lower end side of the ball screw spline shaft 23 via a bearing. The upper end of the bellows 34 is attached to a cover member that is fixed to the bottom surface of the second arm portion 12. A bellows fixing member 37 to which the upper end of the bellows 36 is fixed is attached to the upper end side of the ball screw spline shaft 23 via a bearing. The lower end of the bellows 36 is attached to a cover member 38 that covers the

motors

17, 19, 22 and the like. The cover member 38 is attached to the upper surface side of the second arm portion 12.

In this embodiment, when the motor 22 rotates, the power of the motor 22 is transmitted to the ball screw nut 24 via the

pulleys

28 and 29 and the belt 30, the ball screw nut 24 rotates, and the ball screw spline shaft 23 moves up and down. That is, when the motor 22 rotates in one direction, the end effector attached to the lower end of the ball screw spline shaft 23 rises together with the ball screw spline shaft 23, and when the motor 22 rotates in the other direction, The attached end effector descends together with the ball screw spline shaft 23. When the motor 19 rotates, the power of the motor 19 is transmitted to the spline nut 25 via the

pulleys

21 and 31 and the belt 32, the spline nut 25 rotates, and the ball screw spline shaft 23 rotates about the axis center. To do. That is, the end effector attached to the lower end of the ball screw spline shaft 23 rotates around the axis center of the ball screw spline shaft 23.

Motor

15, 17, 19, 22 is electrically connected to controller 5, and controller 5 controls motor 15, 17, 19, 22. The pendant switch 6 is connected to the control unit 5 via a predetermined cable. In the first embodiment, the

motors

15, 17, 19, and 22 are motors for operating the robot 1, and in the second embodiment, the motor 22 is for operating the robot 1. It is a motor for operation.

[Embodiment 1]
(Motor rotation speed and torque limit value)
FIG. 2 is a graph for explaining the torque limit value of the motor 15 shown in FIG. FIG. 3 is a graph for explaining the torque limit value of the motor 22 shown in FIG. FIG. 4 is a table for explaining an example of a torque limit value table stored in the control unit 5 shown in FIG.

When the robot 1 is installed on an assembly line or the like, the robot 1 is taught. Moreover, the robot 1 after teaching is automatically operated based on the teaching result. In this embodiment, when the teaching is completed, a test operation for confirming whether the teaching point and the control program of the robot 1 are correct is performed as the automatic operation of the robot 1. When the test operation is completed, a normal operation for assembling parts or the like is performed as an automatic operation of the robot 1. Note that switching between the test operation and the normal operation is performed by an operator's operation using the pendant switch 6.

Further, when the operating robot 1 comes into contact with the peripheral device of the robot 1, the

motors

15, 17, 19, and 22 are stopped (that is, the operation of the robot 1 is stopped), and the robot 1 is damaged. In the control unit 5, torque limit values of the

motors

15, 17, 19, and 22 are set. When the torque of the

motors

15, 17, 19, and 22 reaches the torque limit value, the control unit 5 Then, the

motors

15, 17, 19, and 22 are stopped.

In this embodiment, the control unit 5 rotates the

motors

15, 17, 19, and 22 at a rotational speed lower than the rotational speed during the normal operation during the test operation. For example, the control unit 5 rotates the

motors

15, 17, 19, and 22 at a rotation speed of about 10% of the rotation speed during the normal operation during the test operation.

Further, the torque of the

motors

15, 17, 19, and 22 for rotating the

motors

15, 17, 19, and 22 in the one direction is set as a positive torque, and the

motors

15, 17, 19, and 22 are rotated in the other direction. If the torque of the

motors

15, 17, 19, and 22 is a negative torque, in this embodiment, the controller 5 determines whether the

motors

15, 17, 19, and 22 are rotating in one direction during the test operation, When it is determined whether the

motor

15, 17, 19, 22 rotates in one direction while determining whether it is rotating in the other direction, the

motor

15, 17, 19, 22 rotates in one direction during normal operation. When the

motors

15, 17, 19, and 22 are controlled with a torque limit value lower than the torque limit value and the

motors

15, 17, 19, and 22 rotate in the other direction, the motor 15 is operated during normal operation. 17,19,22 is controlling

motor

15,17,19,22 at a high torque limit value than the torque limit value when rotating in the other direction. In this embodiment, the torque limit values of the

motors

15, 17, 19, and 22 during the test operation are the same as the torque limit values of the

motors

15, 17, 19, and 22 when the robot 1 is taught.

Here, even if the rotation direction of the motor 15 changes, the absolute value of the torque required for the motor 15 does not fluctuate greatly due to the influence of gravity such as the arm 3 and the ball screw spline 4. After the servo control is started, the first arm portion 11 stopped at a predetermined position is rotated in one direction with respect to the main body portion 2 and stopped for a predetermined time, and then the first arm portion 11 is moved with respect to the main body portion 2. The torque of the motor 15 when rotated in the direction fluctuates as shown in FIG. 2, for example. Specifically, the torque of the motor 15 during the test operation varies, for example, as the curve S1 in FIG. 2, and the torque of the motor 15 during the normal operation varies, for example, as the curve S2 in FIG. .

Therefore, the absolute value of the torque limit value T1 of the motor 15 when the motor 15 rotates in one direction during the test operation and the absolute value of the torque limit value T2 of the motor 15 when the motor 15 rotates in the other direction during the test operation. Are substantially equal, and the absolute value of the torque limit value T3 of the motor 15 when the motor 15 rotates in one direction during normal operation and the torque of the motor 15 when the motor 15 rotates in the other direction during normal operation The absolute value of the limit value T4 is substantially equal. As described above, when the motor 15 rotates in one direction during the test operation, the motor 15 has a torque limit value T1 that is lower than the torque limit value T3 when the motor 15 rotates in one direction during the normal operation. When the motor 15 rotates in the other direction during the test operation, the motor 15 is controlled with a torque limit value T2 higher than the torque limit value T4 when the motor 15 rotates in the other direction during normal operation. .

Similarly, even if the rotation direction of the

motors

17 and 19 changes, the absolute value of the torque required for the

motors

17 and 19 does not fluctuate greatly due to the influence of gravity such as the arm 3 and the ball screw spline 4. Therefore, the absolute value of the torque limit value of the motor 17 when the motor 17 rotates in one direction during the test operation and the absolute value of the torque limit value of the motor 17 when the motor 17 rotates in the other direction during the test operation. The absolute value of the torque limit value of the motor 17 when the motor 17 rotates in one direction during normal operation and the torque limit value of the motor 17 when the motor 17 rotates in the other direction during normal operation are substantially equal. The absolute value is almost equal. Further, the absolute value of the torque limit value of the motor 19 when the motor 19 rotates in one direction during the test operation and the absolute value of the torque limit value of the motor 19 when the motor 19 rotates in the other direction during the test operation are obtained. The absolute value of the torque limit value of the motor 19 when the motor 19 rotates in one direction during normal operation and the torque limit value of the motor 19 when the motor 19 rotates in the other direction during normal operation are substantially equal. The absolute value is almost equal.

On the other hand, since the motor 22 raises and lowers the end effector together with the ball screw spline shaft 23, the motor 22 raises the end effector due to the weight of the ball screw spline shaft 23, the end effector and the work held by the end effector. The absolute value of torque required for the motor 22 increases, and the absolute value of torque required for the motor 22 decreases when the end effector is lowered. When the motor 22 rotates in one direction, the end effector rises, and when the motor 22 rotates in the other direction, the end effector descends. After the servo control starts, the end effector stopped at a predetermined position is raised. The torque of the motor 22 when the end effector is lowered after being stopped for a predetermined time fluctuates as shown in FIG. 3, for example. Specifically, the torque of the motor 22 during the test operation varies, for example, as the curve S11 in FIG. 3, and the torque of the motor 22 during the normal operation varies, for example, as the curve S12 in FIG. .

Therefore, during the test operation, the torque limit value of the motor 22 when the end effector is raised is the first torque limit value T11, and the torque limit value of the motor 22 when the end effector is lowered is the second torque limit value T12. Then, the controller 5 sets the first torque limit value T11 and the second torque limit value T12 so that the absolute value of the second torque limit value T12 is smaller than the absolute value of the first torque limit value T11. Yes. Similarly, in the control unit 5, the absolute value of the torque limit value T14 of the motor 22 when the end effector is lowered during normal operation is the absolute value of the torque limit value T13 of the motor 22 when the end effector is raised during normal operation. Torque limit values T13 and T14 are set so as to be smaller.

Further, the control unit 5 determines whether the motor 22 is rotating in the direction in which the end effector is raised or whether the motor 22 is rotating in the direction in which the end effector is lowered during the test operation. When the end effector is raised during operation, the motor 22 is controlled based on the first torque limit value T11. When the end effector is lowered during test operation, the motor 22 is controlled based on the second torque limit value T12. . Similarly, during the normal operation, the control unit 5 determines whether the motor 22 is rotating in the direction in which the end effector is raised or whether the motor 22 is rotating in the direction in which the end effector is lowered. At the same time, when the end effector is raised during normal operation, the motor 22 is controlled based on the torque limit value T13, and when the end effector is lowered during normal operation, the motor 22 is controlled based on the torque limit value T14. In this embodiment, when it is determined that the motor 22 is rotating in the direction in which the end effector is raised, the control unit 5 sets the torque limit values T11 and T13 as the torque limit value of the motor 22, and the end effector When it is determined that the motor 22 is rotating in the downward direction, the torque limit values T12 and T14 are set as the torque limit values of the motor 22. That is, the control unit 5 switches the torque limit value of the motor 22 to the torque limit values T11 and T13 or the torque limit values T12 and T14 according to the rotation direction of the motor 22.

As described above, when the motor 22 rotates in one direction during the test operation, the motor has the first torque limit value T11 that is lower than the torque limit value T13 when the motor 22 rotates in one direction during the normal operation. When the motor 22 rotates in the other direction during the test operation, the motor 22 is controlled with a torque limit value T12 higher than the torque limit value T14 when the motor 22 rotates in the other direction during the normal operation. ing. Even when the stopped end effector is held at a predetermined position, the motor 22 is required to have a predetermined holding torque T15 as shown in FIG. In this embodiment, the difference between the first torque limit value T11 and the holding torque T15 and the difference between the second torque limit value T12 and the holding torque T15 are substantially equal, and the torque limit value T13 and the holding torque T15 are different from each other. The difference and the difference between the torque limit value T14 and the holding torque T15 are substantially equal. Furthermore, depending on the torque limit values T12 and T14, the torque of the motor 22 immediately after the start of servo control may be lower than the torque limit values T12 and T14. Therefore, the control unit 5 controls the motor 22 with a torque limit value lower than the torque limit values T12 and T14 within a predetermined time immediately after the start of servo control of the motor 22.

In this embodiment, the operator can input the load weight such as the weight of the end effector and the weight of the work held by the end effector from the pendant switch 6 as the motor load applied to the motor 22. When the load weight is input from the pendant switch 6, the control unit 5 sets torque limit values T11 to T14 based on the input load weight. Specifically, torque limit values T11 to T14 corresponding to the load weight are tabulated and stored in the control unit 5, and the control unit 5 selects the corresponding torque limit value T11 based on the input load weight. Read and set T14. For example, a table as shown in FIG. 4 is stored in the control unit 5, and the control unit 5 reads and sets the corresponding torque limit values T11 to T14 based on the input load weight.

In the example shown in FIG. 4, the difference between the first torque limit value T11 and the second torque limit value T12 and the difference between the torque limit value T13 and the torque limit value T14 are constant regardless of the load weight. However, as the load weight increases, the difference between the first torque limit value T11 and the second torque limit value T12 and the difference between the torque limit value T13 and the torque limit value T14 may increase.

Further, in this embodiment, the torque limit values of the

motors

15, 17, 19 are stored in the control unit 5 as, for example, predetermined fixed values. However, the torque limit values of the

motors

15, 17, and 19 according to the load weight are tabulated and stored in the control unit 5, and the torque limit corresponding to the control unit 5 is based on the load weight input from the pendant switch 6. The value may be read and set.

(Main effects of this form)
As described above, in this embodiment, during the test operation, the

motors

15, 17, 19, and 22 are rotated at a rotation speed lower than the rotation speed during the normal operation. That is, in this embodiment, the operation speed of the robot 1 during the test operation is slow. Therefore, in this embodiment, it is possible to reduce the free running distance of the robot 1 when the operator senses danger during the test operation and makes the robot 1 stop emergency.

Further, in this embodiment, when the

motors

15, 17, 19, and 22 rotate in one direction during the test operation, the torque limit value when the

motors

15, 17, 19, and 22 rotate in one direction during the normal operation. When the

motors

15, 17, 19, and 22 are controlled with a low torque limit value and the

motors

15, 17, 19, and 22 rotate in the other direction during the test operation, the

motors

15, 17, 19, and 22 during the normal operation. The

motors

15, 17, 19, and 22 are controlled with a torque limit value that is higher than the torque limit value when the motor rotates in the other direction. Therefore, in this embodiment, when the robot 1 comes into contact with a peripheral device or the like during a test operation, the torque of the

motors

15, 17, 19, and 22 exceeds the torque limit value or falls below the torque limit value in a short time. . Therefore, in this embodiment, when the robot 1 comes into contact with a peripheral device or the like during a test operation, the

motors

15, 17, 19, and 22 can be stopped in a short time.

Thus, in this embodiment, it is possible to reduce the free running distance of the robot 1 when the operator senses danger during the test operation and stops the robot 1 in an emergency stop. When contacted with a peripheral device or the like, the

motors

15, 17, 19, and 22 can be stopped in a short time. Therefore, in this embodiment, it is possible to prevent the robot 1 from being damaged during the test operation. In addition, when a problem occurs during the test operation, a predetermined measure such as teaching is performed again to prevent the robot 1 from contacting the peripheral device or the like during normal operation after the test operation is completed. This makes it possible to prevent damage to the robot 1 during normal operation. As a result, in this embodiment, it is possible to prevent the robot 1 from being damaged during automatic operation after completion of teaching.

In this embodiment, the first torque limit value T11 and the second torque limit value T12 are set so that the absolute value of the second torque limit value T12 is smaller than the absolute value of the first torque limit value T11. In this embodiment, torque limit values T13 and T14 are set so that the absolute value of torque limit value T14 is smaller than the absolute value of torque limit value T13. For this reason, in this embodiment, when the end effector is normally raised and lowered, the torque of the motor 22 does not exceed the torque limit values T11 and T13 or fall below the torque limit values T12 and T14. When the end effector or the like comes into contact with the peripheral device or the like when the end effector rises, the torque of the motor 22 exceeds the torque limit values T11 or T13, and when the end effector or the like comes into contact with the peripheral device or the like when the end effector descends The torque limit values T11 to T14 can be set so that the torque is less than the torque limit values T12 and T14.

In the present embodiment, the motor 22 is controlled based on the torque limit values T11 and T13 when the end effector is raised, and the motor 22 is controlled based on the second torque limit values T12 and T14 when the end effector is lowered. If the torque of the motor 22 exceeds the torque limit values T11 and T13 when the end effector is raised, or if the torque of the motor 22 falls below the second torque limit values T12 and T14 when the end effector is lowered, the motor 22 Stops. Therefore, in this embodiment, the absolute value of the torque required for the motor 22 when raising the end effector and the motor 22 when lowering the end effector due to the influence of the end effector and the weight of the work held by the end effector. Even if the absolute value of the torque required for the end effector is significantly different, when the end effector or the like comes into contact with a peripheral device or the like when raising or lowering the end effector, the motor 22 is stopped to damage the end effector or the like. It becomes possible to prevent. In this embodiment, the absolute value of the torque required for the motor 22 when the end effector is raised is greatly different from the absolute value of the torque required for the motor 22 when the end effector is lowered. However, when the end effector is normally raised and lowered, the end effector can be raised and lowered appropriately by continuing to rotate the motor 22.

In this embodiment, it is possible to input a load weight such as the weight of the end effector and the weight of the work held by the end effector from the pendant switch 6, and the control unit 5 receives the load weight from the pendant switch 6. Then, torque limit values T11 to T14 are set based on the input load weight. Therefore, in the present embodiment, the torque of the motor 22 exceeds the torque limit values T11 and T13 when the end effector or the like comes into contact with the peripheral device or the like so that the end effector can be raised or lowered more appropriately. The torque limit values T11 to T14 can be set according to the load weight so as to be less than the limit values T12 and T14. Therefore, in this embodiment, the end effector can be raised and lowered more appropriately, and damage to the end effector and the like can be reliably prevented.

(Other embodiments)
The above-described embodiment is an example of a preferred embodiment of the present invention, but is not limited to this, and various modifications can be made without departing from the scope of the present invention.

In the embodiment described above, the control unit 5 rotates the

motors

15, 17, 19, and 22 at a rotation speed lower than the rotation speed during the normal operation during the test operation, and the

motors

15, 17, 19, and 22 during the test operation. When the motor rotates in one direction, the

motors

15, 17, 19, and 22 are controlled with a torque limit value lower than the torque limit value when the

motors

15, 17, 19, and 22 rotate in one direction during normal operation. In addition, when the

motors

15, 17, 19, and 22 rotate in the other direction during the test operation, a torque limit value that is higher than the torque limit value when the

motors

15, 17, 19, and 22 rotate in the other direction during the normal operation. Thus, the

motors

15, 17, 19, and 22 are controlled. In addition to this, for example, the control unit 5 rotates the

motors

15, 17, and 19 at the same speed as the rotation speed during the normal operation and the same torque limit value as that during the normal operation during the test operation. In the same manner as in the above-described embodiment, the motor 22 is rotated at a rotational speed lower than the rotational speed during the normal operation, and the motor 22 rotates in one direction during the test operation. When the motor 22 is controlled with the torque limit value T11 and the motor 22 rotates in the other direction during the test operation, the motor 22 may be controlled with the second torque limit value T12.

Due to the weight of the end effector and the work held by the end effector, the end effector etc. is likely to be damaged if it comes into contact with the peripheral device etc. when it is lowered. It is possible to stop the motor 22 for causing the motor 22 to stop in a short time when the end effector or the like during the test operation contacts the peripheral device or the like, and the operation amount of the end effector after the motor 22 is stopped Can be reduced. Accordingly, it is possible to prevent damage to the end effector and the like during the test operation. In this case, since the

motors

15, 17, and 19 rotate at the same speed as the rotation speed during the normal operation during the test operation, the operation speed of the robot 1 during the test operation can be increased.

In the above-described embodiment, the rotation speed and the torque limit value of the

motors

15, 17, 19, and 22 during the test operation may be selectable. That is, the rotation speed and torque limit value of the

motors

15, 17, 19, and 22 during the test operation may be arbitrarily set by the operator. In this case, the rotation speed and the torque limit value may be selectable for each of the motor 15, the motor 17, the motor 19, and the motor 22. In this case, the test operation of the robot 1 can be performed with various combinations of the rotational speeds of the

motors

15, 17, 19, and 22 and the torque limit values. In this case, during the test operation, the

motors

15, 17, 19, and 22 are rotated at a rotation speed slower than the rotation speed during the normal operation, and the torque limit value is the same as the torque limit value during the normal operation. It is also possible to control at least one of the

motors

15, 17, 19, and 22.

In the embodiment described above, it is possible to input a load weight such as the weight of the end effector or the weight of the work held by the end effector from the pendant switch 6, and the control unit 5 receives the load weight from the pendant switch 6. When input, torque limit values T11 to T14 are set based on the input load weight. In addition to this, for example, a motor load acquisition mode for automatically acquiring the motor load of the motor 22 is provided to acquire the motor load, and the control unit 5 determines the torque limit values T11 to T11 based on the acquired motor load. T14 may be set. That is, the control unit 5 may drive the motor 22 to acquire the motor load of the motor 22, and may set the torque limit values T11 to T14 based on the acquired motor load. In this case, for example, the operation is switched to the motor load acquisition mode by an operation with the pendant switch 6. Further, when the variation of the load weight such as the weight of the end effector or the work held by the end effector is small, the torque limit values T11 to T14 may be stored in the control unit 5 as fixed values.

In the embodiment described above, the control unit 5 controls the motor 22 based on the first torque limit value T11 when the end effector is raised during the test operation, and the first torque when the end effector is lowered during the test operation. The motor 22 is controlled based on the second torque limit value T12 having an absolute value smaller than the absolute value of the limit value T11. In addition to this, for example, the control unit 5 controls the motor 22 based on the first torque limit value T11 when the end effector is raised during the test operation, and also when the end effector is lowered during the test operation. The motor 22 may be controlled based on a second torque limit value that is equal to the absolute value of the first torque limit value T11.

Similarly, in the embodiment described above, the control unit 5 controls the motor 22 based on the torque limit value T13 when the end effector is raised during normal operation, and the torque limit when the end effector is lowered during normal operation. The motor 22 is controlled based on the torque limit value T14 having an absolute value smaller than the absolute value of the value T13, but the control unit 5 is based on the torque limit value T13 when the end effector is raised during normal operation. While controlling the motor 22, the motor 22 may be controlled based on a torque limit value equal to the absolute value of the torque limit value T13 when the end effector descends during normal operation.

In the embodiment described above, when it is determined that the motor 22 is rotating in the direction in which the end effector is raised, the control unit 5 sets the torque limit values T11 and T13 as the torque limit value of the motor 22, and the end effector When it is determined that the motor 22 is rotating in the descending direction, the torque limit values T12 and T14 are set as the torque limit values of the motor 22. In addition to this, for example, the control unit 5 does not determine whether the motor 22 is rotating in the direction in which the end effector is rising or whether the motor 22 is rotating in the direction in which the end effector is descending. When the torque of the motor 22 exceeds the torque limit values T11 and T13, or when the torque of the motor 22 falls below the torque limit values T12 and T14, the motor 22 may be stopped. That is, the control unit 5 may not switch the torque limit value of the motor 22 to the torque limit values T11 and T13 or the torque limit values T12 and T14 according to the rotation direction of the motor 22. Even in this case, the motor 22 is controlled based on the torque limit values T11 and T13 when the end effector is raised, and the motor 22 is controlled based on the torque limit values T12 and T14 when the end effector is lowered.

In the embodiment described above, the arm 3 is constituted by two arm parts, the first arm part 11 and the second arm part 12, but the arm 3 may be constituted by three or more arm parts. .

[Embodiment 2]
(Torque control of lifting motor)
FIG. 5 is a graph for explaining the torque limit value of the motor 22 shown in FIG. FIG. 6 is a table for explaining an example of a torque limit value table stored in the control unit 5 shown in FIG.

When the operating robot 1 comes into contact with the peripheral device of the robot 1, the

motors

15, 17, 19, and 22 are stopped (that is, the operation of the robot 1 is stopped) to prevent the robot 1 from being damaged. Therefore, in the control unit 5, the torque limit values of the

motors

15, 17, 19, and 22 are set, and when the torque of the

motors

15, 17, 19, and 22 reaches the torque limit value, the control unit 5 15, 17, 19, and 22 are stopped.

Even if the rotation direction of the

motors

15, 17 and 19 changes, the absolute value of the torque required for the

motors

15, 17 and 19 does not fluctuate greatly due to the influence of gravity such as the arm 3 and the ball screw spline 4. In the embodiment, the absolute value of the torque limit value of the

motor

15, 17, 19 when the

motor

15, 17, 19 rotates in the forward direction and the

motor

15, 17 when the

motor

15, 17, 19 rotates in the reverse direction. , 19 is the same as the absolute value of the torque limit value.

On the other hand, since the motor 22 raises and lowers the end effector together with the ball screw spline shaft 23, the motor 22 raises the end effector due to the weight of the ball screw spline shaft 23, the end effector and the work held by the end effector. The absolute value of torque required for the motor 22 is increased, and the absolute value of torque required for the motor 22 when the end effector is lowered is decreased. If the torque of the motor 22 in the direction to raise the end effector is a positive torque and the torque of the motor 22 in the direction to lower the end effector is a negative torque, the end effector stopped at a predetermined position after the servo control is started. The torque of the motor 22 when the end effector is lowered after being raised and stopped for a predetermined time varies as shown in FIG. 5, for example. Specifically, the torque of the motor 22 when teaching the robot 1 varies, for example, as shown by a curve S21 in FIG. 5, and the torque of the motor 22 during the automatic operation of the robot 1 after completion of teaching is, for example, It fluctuates like a curve S22 in FIG. That is, the absolute value of the absolute value of the torque required for the motor 22 when the motor 22 rotates in one direction for raising the end effector is the same as that for the motor 22 when the motor 22 rotates in the other direction for lowering the end effector. It becomes larger than the maximum absolute value of the required torque.

Therefore, the torque limit value of the motor 22 when raising the end effector (that is, the torque limit value of the motor 22 when rotating in one direction for raising the end effector) is set as the first torque limit value, and the end effector is lowered. Assuming that the torque limit value of the motor 22 at that time (that is, the torque limit value of the motor 22 when rotating in the other direction to lower the end effector) is the second torque limit value, in the present embodiment, the controller 5 The first torque limit value and the second torque limit value are set so that the absolute value of the torque limit value is smaller than the absolute value of the first torque limit value. Specifically, the first torque limit value T21 and the second torque limit value are set such that the absolute value of the second torque limit value T22 when teaching the robot 1 is smaller than the absolute value of the first torque limit value T21. T22 is set, and the first torque limit value T23 and the absolute value of the second torque limit value T24 during the automatic operation (normal operation) of the robot 1 are smaller than the absolute value of the first torque limit value T23. A second torque limit value T24 is set (see FIG. 5). More specifically, when the end effector is moving up and down normally, the torque of the motor 22 does not exceed the first torque limit values T21 and T23 or fall below the second torque limit values T22 and T24. Further, when the end effector etc. comes into contact with the peripheral device etc. when the end effector is raised, the torque of the motor 22 exceeds the first torque limit values T21, T23, and when the end effector is lowered, the end effector etc. The first torque limit values T21 and T23 and the second torque limit values T22 and T24 are set so that the torque of the motor 22 falls below the second torque limit values T22 and T24 when contacted.

Further, the first torque limit value T21 at the time of teaching is different from the first torque limit value T23 at the time of automatic operation. The second torque limit value T22 at the time of teaching and the second torque limit value T24 at the time of automatic operation are different. Is different. Specifically, as shown in FIG. 5, the first torque limit value T21 is smaller than the first torque limit value T23, and the second torque limit value T22 is larger than the second torque limit value T24. It has become. Even when the stopped end effector is held at a predetermined position, the motor 22 is required to have a predetermined holding torque T25 as shown in FIG. In this embodiment, the difference between the first torque limit value T21 and the holding torque T25 and the difference between the second torque limit value T22 and the holding torque T25 are substantially equal, and the first torque limit value T23 and the holding torque T25 are the same. And the difference between the second torque limit value T24 and the holding torque T25 are substantially equal.

Further, when teaching the robot 1, the controller 5 determines whether the motor 22 is rotating in the direction in which the end effector is raised or whether the motor 22 is rotating in the direction in which the end effector is lowered. In addition, when the end effector is raised when teaching the robot 1, the motor 22 is controlled based on the first torque limit value T21. When the end effector is lowered when teaching the robot 1, the second torque limit value T22 is controlled. The motor 22 is controlled based on the above. That is, when the end effector is raised when teaching the robot 1, the torque of the motor 22 exceeds the first torque limit value T21, or when the end effector is lowered, the torque of the motor 22 becomes the second torque limit value T22. If it falls below, the control unit 5 stops the motor 22. In this embodiment, when the controller 5 teaches the robot 1 and determines that the motor 22 is rotating in the direction in which the end effector is raised, the controller 5 sets the first torque limit value T21 of the motor 22. When the torque limit value is set and it is determined that the motor 22 is rotating in the direction in which the end effector descends, the second torque limit value T22 is set as the torque limit value of the motor 22. That is, the control unit 5 switches the torque limit value of the motor 22 to the first torque limit value T21 or the second torque limit value T22 according to the rotation direction of the motor 22.

Similarly, the controller 5 determines whether the motor 22 is rotating in the direction in which the end effector is raised or the motor 22 is rotating in the direction in which the end effector is lowered during automatic operation of the robot 1. When the end effector is raised during automatic operation of the robot 1, the motor 22 is controlled based on the first torque limit value T23. When the end effector is lowered during automatic operation of the robot 1, the second effector is The motor 22 is controlled based on the torque limit value T24. That is, if the torque of the motor 22 exceeds the first torque limit value T23 when the end effector is raised during the automatic operation of the robot 1, or if the end effector is lowered, the torque of the motor 22 is the second torque limit value T24. If it falls below, the control unit 5 stops the motor 22. In this embodiment, when the controller 5 determines that the motor 22 is rotating in the direction in which the end effector is raised during automatic operation of the robot 1, the controller 5 sets the first torque limit value T <b> 23 to the motor 22. When it is determined that the motor 22 is rotating in the direction in which the end effector descends, the second torque limit value T24 is set as the torque limit value of the motor 22. That is, the control unit 5 switches the torque limit value of the motor 22 to the first torque limit value T23 or the second torque limit value T24 according to the rotation direction of the motor 22.

Note that, depending on the values of the second torque limit values T22 and T24, the torque of the motor 22 immediately after the start of servo control may be lower than the second torque limit values T22 and T24. Therefore, the control unit 5 controls the motor 22 with a torque limit value lower than the second torque limit values T22 and T24 within a predetermined time immediately after the start of servo control of the motor 22. Further, the rotational speeds of the

motors

15, 17, 19, and 22 when teaching the robot 1 are slower than the rotational speeds of the

motors

15, 17, 19, and 22 when the robot 1 is automatically operated.

In this embodiment, the operator can input the load weight such as the weight of the end effector and the weight of the work held by the end effector from the pendant switch 6 as the motor load applied to the motor 22. When the load weight is input from the pendant switch 6, the control unit 5 sets the first torque limit values T21 and T23 and the second torque limit values T22 and T24 based on the input load weight. Specifically, the first torque limit values T21 and T23 and the second torque limit values T22 and T24 corresponding to the load weight are tabulated and stored in the control unit 5, and the control unit 5 receives the input load. Based on the weight, the corresponding first torque limit values T21, T23 and second torque limit values T22, T24 are read and set. For example, a table as shown in FIG. 6 is stored in the control unit 5, and the control unit 5 performs the corresponding first torque limit values T21, T23 and second torque limit value T22 based on the input load weight. , T24 is read and set.

In the example shown in FIG. 6, the difference between the first torque limit value T21 and the second torque limit value T22 and the difference between the first torque limit value T23 and the second torque limit value T24 are related to the load weight. Although it is constant, the difference between the first torque limit value T21 and the second torque limit value T22 and the difference between the first torque limit value T23 and the second torque limit value T24 as the load weight increases. The difference may be large.

(Main effects of this form)
As described above, in the present embodiment, when the end effector is moving up and down normally, the torque of the motor 22 exceeds the first torque limit values T21 and T23 or falls below the second torque limit values T22 and T24. In addition, when the end effector and the like come into contact with peripheral devices when the end effector is raised, the torque of the motor 22 exceeds the first torque limit values T21 and T23, and when the end effector is lowered, The first torque limit values T21 and T23 and the second torque limit values T22 and T24 are set so that the torque of the motor 22 falls below the second torque limit values T22 and T24 when contacting with a peripheral device or the like. In this embodiment, when the end effector is raised (that is, when the motor 22 rotates in one direction for raising the end effector), the motor 22 is controlled based on the first torque limit values T21 and T23, and the end effector is The motor 22 is controlled based on the second torque limit values T22 and T24 when the end effector is lowered (that is, when the motor 22 rotates in the other direction for lowering the end effector). When the torque exceeds the first torque limit values T21 and T23, or when the torque of the motor 22 falls below the second torque limit values T22 and T24 when the end effector is lowered, the motor 22 stops.

Therefore, in this embodiment, when the end effector or the like comes into contact with a peripheral device or the like when the end effector moves up and down, it is possible to stop the motor 22 and prevent the end effector or the like from being damaged. Further, in this embodiment, when the end effector is normally raised and lowered, the end effector can be raised and lowered appropriately by continuing to rotate the motor 22. That is, in this embodiment, when a part of the robot 1 comes into contact with a peripheral device or the like while the motor 22 is rotating, it is possible to stop the motor 22 and prevent damage to the robot 1 and the peripheral device or the like. At the same time, when the motor 22 is rotated and the robot 1 is operating normally, it is possible to continue the rotation of the motor 22 and operate the robot 1 appropriately.

In this embodiment, it is possible to input a load weight such as the weight of the end effector or the weight of the work held by the end effector from the pendant switch 6, and the control unit 5 receives the load weight from the pendant switch 6. Then, the first torque limit values T21 and T23 and the second torque limit values T22 and T24 are set based on the input load weight. Therefore, in the present embodiment, the torque of the motor 22 exceeds the first torque limit values T21 and T23 so that the end effector can be moved up and down more appropriately and when the end effector or the like comes into contact with the peripheral device or the like. The first torque limit values T21 and T23 and the second torque limit values T22 and T24 can be set according to the load weight so as to be lower than the second torque limit values T22 and T24. Therefore, in this embodiment, the end effector can be raised and lowered more appropriately, and damage to the end effector and the like can be reliably prevented.

In this embodiment, the control unit 5 controls the motor 22 based on the first torque limit value T21 when the end effector is raised when teaching the robot 1, and when the end effector is lowered when teaching the robot 1, The motor 22 is controlled based on the second torque limit value T22. At the time of teaching that the robot 1 is operated by an operator's manual operation, the end effector etc. is more likely to come into contact with the peripheral device etc. and damage the end effector etc., compared with the automatic operation of the robot 1. Then, even when teaching the robot 1, it becomes possible to prevent damage to the end effector and the like.

In this embodiment, the first torque limit value T21 when teaching the robot 1 is smaller than the first torque limit value T23 during automatic operation of the robot 1, and the second torque limit value when teaching the robot 1 The value T22 is larger than the second torque limit value T24 during automatic operation of the robot 1. Therefore, in this embodiment, as described above, the rotational speed of the motor 22 when the robot 1 is automatically operated can be made faster than the rotational speed of the motor 22 when the robot 1 is taught. Therefore, in this embodiment, it is possible to increase the lifting speed of the end effector during automatic operation of the robot 1.

In the embodiment described above, it is possible to input a load weight such as the weight of the end effector or the weight of the work held by the end effector from the pendant switch 6, and the control unit 5 receives the load weight from the pendant switch 6. When input, the first torque limit values T21 and T23 and the second torque limit values T22 and T24 are set based on the input load weight. In addition to this, for example, a motor load acquisition mode for automatically acquiring the motor load of the motor 22 is provided to acquire the motor load, and the control unit 5 determines the first torque limit value based on the acquired motor load. T21 and T23 and second torque limit values T22 and T24 may be set. That is, the control unit 5 drives the motor 22 to acquire the motor load of the motor 22 and, based on the acquired motor load, the first torque limit values T21 and T23 and the second torque limit values T22 and T24. May be set. In this case, for example, the operation is switched to the motor load acquisition mode by an operation with the pendant switch 6. Further, when the variation of the load weight such as the weight of the end effector or the work held by the end effector is small, the first torque limit values T21 and T23 and the second torque limit values T22 and T24 are controlled as fixed values. It may be stored in the unit 5.

In the embodiment described above, the control unit 5 controls the motor 22 based on the first torque limit value T23 when the end effector is raised during the automatic operation of the robot 1, and the end effector during the automatic operation of the robot 1 is controlled. When descending, the motor 22 is controlled based on the second torque limit value T24 having an absolute value smaller than the absolute value of the first torque limit value T23. In addition to this, for example, the control unit 5 controls the motor 22 based on the first torque limit value T23 when the end effector is raised during the automatic operation of the robot 1, and also ends the automatic operation of the robot 1. When the effector is lowered, the motor 22 may be controlled based on a second torque limit value that is equal to the absolute value of the first torque limit value T23.

In the embodiment described above, when the controller 5 teaches the robot 1 and determines that the motor 22 is rotating in the direction in which the end effector is raised, the controller 5 sets the first torque limit value T21 to the torque of the motor 22. When the limit value is set and it is determined that the motor 22 is rotating in the direction in which the end effector descends, the second torque limit value T22 is set as the torque limit value of the motor 22. In addition to this, for example, when the controller 5 teaches the robot 1, the motor 22 is rotated in the direction in which the end effector is raised or the motor 22 is rotated in the direction in which the end effector is lowered. Even if the motor 22 is stopped when the torque of the motor 22 exceeds the first torque limit value T21 or when the torque of the motor 22 falls below the second torque limit value T22 good. That is, when teaching the robot 1, the controller 5 does not have to switch the torque limit value of the motor 22 to the first torque limit value T21 or the second torque limit value T22 according to the rotation direction of the motor 22. . Even in this case, the motor 22 is controlled based on the first torque limit value T21 when the end effector is raised, and the motor 22 is controlled based on the second torque limit value T22 when the end effector is lowered.

Similarly, in the above-described form, when the control unit 5 determines that the motor 22 is rotating in the direction in which the end effector is raised during the automatic operation of the robot 1, the control unit 5 sets the first torque limit value T23. If the motor 22 is set as the torque limit value and it is determined that the motor 22 is rotating in the direction in which the end effector descends, the second torque limit value T24 is set as the torque limit value of the motor 22. The controller 5 does not determine whether the motor 22 is rotating in the direction in which the end effector is rising or whether the motor 22 is rotating in the direction in which the end effector is descending, and the torque of the motor 22 is determined. The motor 22 may be stopped when the first torque limit value T23 is exceeded or when the torque of the motor 22 falls below the second torque limit value T24. That is, the controller 5 does not have to switch the torque limit value of the motor 22 to the first torque limit value T21 or the second torque limit value T22 according to the rotation direction of the motor 22 during the automatic operation of the robot 1. good. Even in this case, when the end effector is raised, the motor 22 is controlled based on the first torque limit value T23, and when the end effector is lowered, the motor 22 is controlled based on the second torque limit value T24.

[Variation 1 of industrial robot]
FIG. 7 is a plan view of an industrial robot 1 according to another embodiment of the present invention. FIG. 8 is a side view showing the industrial robot 1 from the EE direction of FIG. FIG. 9 is a side view of an industrial robot 1 according to another embodiment of the present invention. FIG. 10 is a plan view for explaining the lifting mechanism of the industrial robot 1 shown in FIG.

The robot 1 to which the present invention is applied may be a horizontal articulated robot for transferring an object to be transferred such as a glass substrate for a liquid crystal display or a semiconductor wafer. For example, as shown in FIGS. 7 and 8, the robot 1 may be a horizontal articulated robot for transporting a glass substrate 42 for liquid crystal display (hereinafter referred to as “substrate 42”). The robot 1 is disposed in the atmosphere. In addition, the robot 1 includes two hands 43 as end effectors on which the substrate 42 is mounted, two arms 44 to which the two hands 43 are connected to the distal end side, and two arms 44. A main body portion 45 to be supported and a base member 46 to support the main body portion 45 so as to be movable in the horizontal direction are provided. The main body 45 has an arm support member 47 that supports the proximal end sides of the two arms 44, an elevating member 48 that can move up and down while the arm support member 47 is fixed, and the elevating member 48 can be moved in the vertical direction. A columnar member 49 supported on the base member 50, a base 50 that constitutes a lower end portion of the main body 45 and is horizontally movable with respect to the base member 46, and a lower end of the columnar member 49 is fixed and pivoted with respect to the base 50 The possible turning member 51 is provided.

The elevating member 48 is movable up and down with respect to the columnar member 49, and the robot 1 includes an elevating mechanism that elevates the elevating member 48. The elevating mechanism is engaged with the elevating motor for elevating the hand 43, a ball screw rotatably attached to the columnar member 49 with the vertical direction as an axial direction, and rotated by the power of the elevating motor. And a nut member attached to the elevating member 48. In the robot 1 shown in FIGS. 7 and 8, when the lifting motor rotates in one direction, the hand 43, the arm 44, the arm support member 47, and the lifting member 48 rise, and when the lifting motor rotates in the other direction, 43, the arm 44, the arm support member 47, and the elevating member 48 are lowered. In the robot 1 shown in FIGS. 7 and 8, the lifting motor is an operating motor for operating the robot 1. The lifting motor is connected to the control unit, and the control unit controls the lifting motor. The arm 44 is an end effector attachment member to which the hand 43 as an end effector is attached.

Also in the robot 1 shown in FIGS. 7 and 8, similarly to the above-described embodiment, the absolute values of the second torque limit values T22 and T24 that are torque limit values of the lifting motor when the hand 43 is lowered are the hand 43. The first torque limit values T21, T23 and the second torque limit values T22, T24 are set so as to be smaller than the absolute values of the first torque limit values T21, T23, which are torque limit values of the lifting motor when raising Is set. When the hand 43 is raised, the lifting motor is controlled based on the first torque limit values T21 and T23, and when the hand 43 is lowered, the lifting motor is controlled based on the second torque limit values T22 and T24. Yes. Therefore, also in the robot 1 shown in FIGS. 7 and 8, the same effect as the above-described embodiment can be obtained.

The robot 1 may be a horizontal articulated robot for transporting a semiconductor wafer 52 (hereinafter referred to as “wafer 52”) as shown in FIGS. 9 and 10, for example. The robot 1 is disposed in the atmosphere. Further, the robot 1 includes two hands 53 as end effectors on which the wafer 52 is mounted, two arms 54 to which the two hands 53 are respectively connected to the distal end side, and two arms 54. And a main body 55 to be supported. The main body 55 includes a base 56 and three frames 57 to 59. The frame 57 is held by the base 56 so that it can be raised and lowered, the frame 58 is held by the frame 57 so that it can be raised and lowered, and the frame 59 is held by the frame 58 so that it can be raised and lowered. An arm support member 60 is fixed to the upper end of the frame 59, and the base end sides of the two arms 54 are rotatably connected to the arm support member 60.

Further, the robot 1 raises and lowers the frame 57 with respect to the base 56, raises and lowers the frame 58 with respect to the frame 57, and raises and lowers the frame 59 with respect to the frame 58 to expand and contract the frames 57 to 59. Thus, an elevating mechanism for elevating the hand 53 and the arm 54 is provided. This elevating mechanism includes a motor (elevating motor) 61 for elevating and lowering the hand 53, a ball screw 62 that is rotatably attached to a base 56 with the vertical direction as an axial direction, and a ball screw 62 that is rotated by the power of the motor 61. A nut member 63 that is engaged and attached to the frame 57, a moving pulley means 64 that has a pulley and a belt and connects the frame 57 and the frame 58, and a pulley and a belt that connects the frame 58 and the frame 59. The movable pulley means 65 is provided. In this lifting mechanism, the cylinder rod of the balancer cylinder 66 is attached to the frame 57, and the frame 57 is always urged upward by the balancer cylinder 66.

In the robot 1 shown in FIGS. 9 and 10, when the motor 61 rotates in one direction, the frame 57 rises and the

frames

58 and 59 rise due to the action of the movable pulley means 64 and 65. When rotating in the direction, the frame 57 is lowered and the

frames

58 and 59 are lowered by the action of the moving pulley means 64 and 65. That is, when the motor 61 rotates in one direction, the hand 53, the arm 54, the arm support member 60 and the frames 57 to 59 rise, and when the motor 61 rotates in the other direction, the hand 53, the arm 54, the arm support member 60 and The frames 57 to 59 are lowered. In the robot 1 shown in FIGS. 9 and 10, the motor 61 is an operation motor for operating the robot 1. The motor 61 is connected to the control unit, and the control unit controls the motor 61. The arm 54 is an end effector attachment member to which a hand 53 as an end effector is attached.

Also in the robot 1 shown in FIGS. 9 and 10, the absolute values of the second torque limit values T <b> 22 and T <b> 24 that are the torque limit values of the motor 61 when the hand 53 is lowered are The first torque limit values T21, T23 and the second torque limit values T22, T24 are set so as to be smaller than the absolute values of the first torque limit values T21, T23, which are the torque limit values of the motor 61 when increasing. ing. When the hand 53 is raised, the motor 61 is controlled based on the first torque limit values T21 and T23, and when the hand 53 is lowered, the motor 61 is controlled based on the second torque limit values T22 and T24. Therefore, the robot 1 shown in FIGS. 9 and 10 can obtain the same effects as those of the above-described embodiment.

[Modification 2 of industrial robot]
FIG. 11 is a diagram of an industrial robot 1 according to another embodiment of the present invention, in which (A) is a plan view and (B) is a side view. FIG. 12 is a cross-sectional view for explaining the internal structure of the F portion in FIG.

The robot 1 to which the present invention is applied may be a horizontal articulated robot for transporting a glass substrate for an organic EL (organic electroluminescence) display in a vacuum. The robot 1 includes a hand 73 as an end effector on which a glass substrate is mounted, an arm 74 to which the hand 73 is connected to the distal end side, a main body 75 to which the base end side of the arm 74 is rotatably connected, An elevating mechanism 76 that elevates and lowers the main body 75 is provided. The main body 75 and the elevating mechanism 76 are accommodated in a substantially bottomed cylindrical case body 77. The case body 77 includes a flange portion 77a formed in a disc shape. The flange portion 77 a constitutes the upper end portion of the case body 77. The flange portion 77a is formed with a through hole in which the upper end portion of the main body portion 75 is disposed.

The hand 73 and the arm 74 are arranged on the upper side of the main body 75. Moreover, the hand 73 and the arm 74 are arrange | positioned above the flange part 77a. A portion of the robot 1 above the lower end surface of the flange portion 77a is disposed in the vacuum chamber. That is, the part above the lower end surface of the flange part 77a of the robot 1 is disposed in the vacuum region VR, and the hand 73 and the arm 74 are disposed in a vacuum. On the other hand, a portion of the robot 1 below the lower end surface of the flange portion 77a is disposed in the atmospheric region AR (in the atmosphere).

A motor 78 for rotating the arm 74 with respect to the main body 75 is attached to the main body 75. The main body 75 holds a hollow rotary shaft 79 to which the base end side of the arm 74 is fixed, a speed reducer 80 that reduces the rotation of the motor 78 and transmits it to the arm 74, and a case body of the speed reducer 80. And a substantially cylindrical holding member 81 that rotatably holds the hollow rotary shaft 79. The hollow rotary shaft 79 and the holding member 81 are arranged so that the axial direction thereof coincides with the vertical direction. The base end side of the arm 74 is fixed to the upper end of the hollow rotary shaft 79.

A magnetic fluid seal 83 that prevents the outflow of air to the vacuum region VR is disposed at a joint portion that connects the main body portion 75 and the arm 74 (that is, a joint portion that connects the hollow rotary shaft 79 and the arm 74). . The magnetic fluid seal 83 is disposed between the outer peripheral surface of the hollow rotary shaft 79 and the inner peripheral surface of the holding member 81. Moreover, the bellows 84 for preventing the outflow of the air to the vacuum area | region VR is arrange | positioned at the joint part 82. FIG. The bellows 84 is disposed inside the case body 77 so as to cover a part of the outer peripheral side on the upper end side of the holding member 81. The lower end of the bellows 84 is fixed to the holding member 81, and the upper end of the bellows 84 is fixed to the flange portion 77a. The inner peripheral side of the bellows 84 is in a vacuum, and the outer peripheral side of the bellows 84 is at atmospheric pressure. When a later-described motor 86 that constitutes the lifting mechanism 76 rotates and the main body 75 moves up and down, the bellows 84 expands and contracts.

The elevating mechanism 76 includes a motor 86 for elevating and lowering the main body 75, a ball screw 87 that is rotatably attached to the case body 77 with the vertical direction as an axial direction, and a ball screw 87 that rotates by the power of the motor 86. And a nut member 88 attached to the main body 75. In the robot 1 shown in FIGS. 11 and 12, when the motor 86 rotates in one direction, the hand 73, the arm 74, and the main body 75 are lowered, and when the motor 86 rotates in the other direction, the hand 73, the arm 74, and the main body. 75 rises. In the robot 1 shown in FIGS. 11 and 12, the motor 86 is an operation motor for operating the robot 1. The motor 86 is connected to the control unit, and the control unit controls the motor 86. The arm 74 is an end effector attachment member to which a hand 73 as an end effector is attached. Further, in the robot 1 shown in FIGS. 11 and 12, the hollow rotary shaft 79 and the holding member 81 constitute a shaft member on which an arm 74 as an end effector mounting member is fixed to the upper end. Even when the main body 75 is raised, the lower end side of the shaft member is accommodated in the case body 77.

In the robot 1 shown in FIGS. 11 and 12, the hand 73 and the arm 74 are arranged in a vacuum, and when the main body 75 is lowered together with the hand 73 and the arm 74 and the bellows 84 is extended, negative pressure is generated. Then, since a large force that pushes up the hand 73, the arm 74, and the main body portion 75 acts, the absolute value of the torque required for the motor 86 when the hand 73 is lowered increases and the hand 73 is raised. The absolute value of torque required for the motor 86 is reduced. That is, the maximum value of the absolute value of the torque required for the motor 86 when the motor 86 rotates in one direction for lowering the hand 73 is the same as that for the motor 86 when the motor 86 rotates in the other direction for lifting the hand 73. It becomes larger than the maximum absolute value of the required torque.

Therefore, in the robot 1 shown in FIGS. 11 and 12, the absolute value of the second torque limit value, which is the torque limit value of the motor 86 when the hand 73 is raised, lowers the hand 73, contrary to the above-described form. The first torque limit value and the second torque limit value are set so as to be smaller than the absolute value of the first torque limit value, which is the torque limit value of the motor 86 at the time. When the hand 73 is lowered, the motor 86 is controlled based on the first torque limit value, and when the hand 73 is lowered, the motor 86 is controlled based on the second torque limit value. Therefore, also in the robot 1 shown in FIGS. 11 and 12, the same effect as the above-described embodiment can be obtained.

11 and 12, the upper end of the bellows 84 is fixed to the upper end side of the hollow rotary shaft 79 so that the inner peripheral side of the bellows 84 is atmospheric pressure and the outer peripheral side of the bellows 84 is vacuum. The lower end of the bellows 84 may be fixed to the flange portion 77a. In this case, the bellows 84 is disposed outside the case body 77 so as to cover a part of the outer peripheral side on the upper end side of the hollow rotary shaft 79. Even in this case, when the main body 75 is lowered together with the hand 73 and the arm 74 and the bellows 84 is extended, a negative pressure is generated, and a large force that pushes the hand 73, the arm 74, and the main body 75 upward is generated. Therefore, the absolute value of the second torque limit value that is the torque limit value of the motor 86 when the hand 73 is raised is equal to the first torque limit value that is the torque limit value of the motor 86 when the hand 73 is lowered. The first torque limit value and the second torque limit value are set so as to be smaller than the absolute value. When the hand 73 is lowered, the motor 86 is controlled based on the first torque limit value. When the hand 73 is lowered, the motor 86 is controlled based on the second torque limit value.

[Modification 3 of industrial robot]
FIG. 13 is a perspective view of a battery exchange system in which a robot 1 according to another embodiment of the present invention is installed. FIG. 14 is a perspective view showing part G of FIG. 13 from another angle. FIG. 15 is a schematic diagram for explaining the configuration of the battery 103 and the battery housing portion 104 shown in FIG. FIG. 16 is a diagram showing the battery insertion / removal mechanism 117 and the lifting / lowering mechanism 118 shown in FIG. 14 from the front. FIG. 17 is a diagram showing the battery insertion / removal mechanism 117 and the lifting / lowering mechanism 118 from the HH direction of FIG. FIG. 18 is a view for explaining the battery moving mechanism 125 shown in FIG. 16 from the side. In the following description, the two directions orthogonal to each other in the horizontal direction are defined as the X direction and the Y direction, the X direction is defined as the front-rear direction, and the Y direction is defined as the left-right direction.

The robot 1 to which the present invention is applied may be a battery replacement robot for replacing the battery 103 mounted on the vehicle 102. The vehicle 102 is, for example, an electric bus. A battery housing portion 104 that houses a plurality of batteries 103 is attached to the vehicle 102. When the battery 103 is replaced, the vehicle 102 is stopped so that the traveling direction thereof substantially coincides with the left-right direction. The robot 1 faces the side surface 102a of the vehicle 102 in the front-rear direction so that the battery 103 housed in the battery housing portion 104 can be replaced. The robot 1 pulls out the battery 103 accommodated in the battery accommodating portion 104 and carries it into a buffer station (not shown), and carries out the charged battery 103 accommodated in the buffer station from the buffer station. Insert into the storage section 104.

The battery housing portion 104 includes a battery mount 106 on which the battery 103 is mounted, and left and right side walls 107, and a housing space for the battery 103 is formed by the battery mount 106 and the side wall 107. In the battery housing portion 104, housing spaces for a plurality of batteries 103 are formed, and a plurality of batteries 103 can be housed. Further, as shown in FIG. 15, the battery housing portion 104 includes a lock mechanism 109 that locks the battery 103 that is housed, and a connector 110 that electrically connects the vehicle 102 and the battery 103. The lock mechanism 109 includes a lock member 111 and an urging member 112. The connector 110 is disposed on the back side of the battery housing portion 104.

The lock member 111 is held on the side wall 107 so as to be movable in the left-right direction, for example. The lock member 111 is biased inward in the left-right direction by a biasing member (not shown) and protrudes from the side wall 107 to the inside of the battery housing portion 104. Further, the lock member 111 is formed in, for example, a substantially triangular prism shape, and an inclined surface 111a that is inclined with respect to a plane constituted by the front-rear direction and the vertical direction, and a plane constituted by the horizontal direction and the vertical direction. And an end face 111b parallel to each other. The end surface 111 b constitutes an end surface on the back side of the lock member 111. The inclined surface 111a is inclined so as to spread outward in the left-right direction toward the front side of the battery housing portion 104.

The urging member 112 is, for example, a compression coil spring. The biasing member 112 faces the front side of the battery housing portion 104 so that an end surface 115b of an engagement protrusion 115 described later formed on the battery 103 and an end surface 111b of the lock member 111 are in contact with each other with a predetermined contact pressure. The battery 103 is energized. In the vehicle 102, the battery 103 is urged by the urging member 112, so that the vibration of the battery 103 accommodated in the battery accommodating portion 104 during traveling of the vehicle 102 is suppressed.

A handle portion 114 for pulling out the battery 103 from the battery housing portion 104 is formed on the front surface of the battery 103. Further, as shown in FIG. 15, the battery 103 includes an engagement protrusion 115 that engages with the lock member 111 and a connector 116 that is connected to the connector 110. The connector 116 is attached to the back end surface (back surface) of the battery 103 housed in the battery housing portion 104.

The engaging protrusions 115 are fixed to the left and right side surfaces of the battery 103, for example, and protrude outward from the left and right side surfaces of the battery 103 in the left and right direction. The engaging protrusion 115 is formed in, for example, a substantially triangular prism shape, and is an inclined surface 115a that is inclined with respect to a plane constituted by the front-rear direction and the vertical direction, and a plane constituted by the left-right direction and the vertical direction. And an end face 115b parallel to each other. The end surface 115b constitutes an end surface on the near side of the engagement protrusion 115. The inclined surface 115a is inclined so as to spread outward in the left-right direction as it goes toward the front side of the battery housing portion 104.

When the battery 103 is inserted into the battery accommodating portion 104 when the battery 103 is accommodated in the battery accommodating portion 104, the inclined surface 115a of the engaging protrusion 115 and the inclined surface 111a of the lock member 111 come into contact with each other. When the battery 103 is further inserted into the battery housing portion 104 in this state, as shown in FIG. 15 (B), the lock member 111 is moved to the left and right against the urging force of the urging member that urges the lock member 111. Move out of direction. When the battery 103 is further inserted until the engagement protrusion 115 passes through the lock member 111, the lock member 111 moves inward in the left-right direction by the urging force of the urging member. Further, when the battery 103 is further inserted until the engagement protrusion 115 passes through the lock member 111, the urging member 112 contacts the back end surface of the battery 103, and the battery 103 is moved toward the front side of the battery housing portion 104. Energize.

Then, as shown in FIG. 15C, the end surface 115b of the engagement protrusion 115 formed on the battery 103 and the end surface 111b of the lock member 111 come into contact with each other with a predetermined contact pressure, and are stored in the battery storage unit 104. The battery 103 is locked. As described above, the lock mechanism 109 is a mechanical lock mechanism that is operated by the insertion force of the battery 103 into the battery housing portion 104 and locks the battery 103. Specifically, the lock mechanism 109 is a mechanical lock mechanism that operates by the insertion force of the battery 103 into the battery housing portion 104 by a battery engagement portion 124 (to be described later) constituting the robot 1 to lock the battery 103. . Further, the connector 110 and the connector 116 are connected by the insertion force of the battery 103 into the battery housing portion 104. Specifically, the connector 110 and the connector 116 are connected by the insertion force of the battery 103 into the battery housing part 104 by the battery engaging part 124 described later.

15C (that is, from the state in which the battery 103 is locked to the lock mechanism 109), when the battery 103 is further pushed into the back side of the battery housing portion 104, the lock member 111 is retracted. Thus, the lock mechanism 109 is configured so that the contact state between the end surface 115b and the end surface 111b is released. Therefore, when the battery 103 is further pushed into the back side of the battery housing portion 104 from the state in which the battery 103 is locked to the lock mechanism 109, the lock state of the battery 103 by the lock mechanism 109 is released, and the battery housing portion 104 The battery 103 can be pulled out.

The robot 1 includes a battery insertion / removal mechanism 117 that pulls out the battery 103 from the battery housing portion 104 and inserts the battery 103 into the battery housing portion 104, a lifting mechanism 118 that lifts and lowers the battery insertion / removal mechanism 117, and a vertical direction. A rotation mechanism 119 that rotates the battery insertion / removal mechanism 117 and the lifting / lowering mechanism 118 as an axial direction, and a horizontal movement mechanism 120 that moves the battery insertion / removal mechanism 117, the lifting / lowering mechanism 118, and the rotation mechanism 119 in the left-right direction are provided. Yes.

The battery insertion / removal mechanism 117 includes a battery mounting mechanism 123 having a battery mounting portion 122 on which the battery 103 is mounted when the battery 103 is pulled out and inserted, and is engaged with the battery 103 when the battery 103 is pulled out and inserted. A battery moving mechanism 125 having a battery engaging portion 124 for moving the battery 103 on the portion 122. Further, the battery insertion / removal mechanism 117 is held by the holding member 126. The battery mounting mechanism 123 includes a mounting portion moving mechanism that moves the battery mounting portion 122 in a direction approaching the vehicle 102 and a direction away from the vehicle 102. The battery mounting unit 122 moves in a direction approaching the vehicle 102 when the battery 103 is replaced, and stands by at a position away from the vehicle 102 when the battery 103 is not replaced.

The battery moving mechanism 125 includes an engaging portion moving mechanism 139 that moves the battery engaging portion 124 in the direction approaching the vehicle 102 and the direction away from the vehicle 102, the battery engaging portion 124 movably held, and the holding member 126. And a movable holding member 140 that is held so as to be movable. The battery engaging portion 124 includes an engaging claw portion 141 that engages with the handle portion 114 of the battery 103 and an air cylinder 142 that moves the engaging claw portion 141 up and down.

The moving holding member 140 is formed in an elongated shape in the moving direction of the battery engaging portion 124. The engaging portion moving mechanism 139 includes a motor 144, a ball screw 145, a nut member 146 that is screwed into the ball screw 145, and pulleys 147 and 148 as a configuration for moving the battery engaging portion 124 and the movement holding member 140. And a belt 149 laid over

pulleys

147 and 148. The motor 144 is fixed to the rear end portion of the holding member 126. The ball screw 145 is rotatably held on the upper surface portion of the holding member 126 and is rotated by the power of the motor 144. The nut member 146 is fixed to the rear end portion of the movement holding member 140. The pulley 147 is rotatably held at the rear end portion of the movement holding member 140, and the pulley 148 is rotatably held at the front end portion of the movement holding member 140. The belt 149 is fixed to the battery engaging portion 124 via the belt fixing member 154 and is fixed to the upper surface portion of the holding member 126 via the belt fixing member 155.

In the robot 1 shown in FIG. 14 and the like, when the motor 144 rotates, the battery engaging portion 124 moves linearly. Specifically, when the motor 144 rotates in one direction, the battery engaging portion 124 moves in a direction approaching the vehicle 102, and when the motor 144 rotates in the other direction, the battery engaging portion 124 moves away from the vehicle 102. Moving. Therefore, in the robot 1 shown in FIG. 14 and the like, when the motor 144 rotates in one direction, the battery engagement portion 124 inserts the battery 103 into the battery housing portion 104, and when the motor 144 rotates in the other direction, the battery The engaging part 124 pulls out the battery 103 from the battery housing part 104. In the robot 1 shown in FIG. 14 and the like, the motor 144 is a pull-out insertion motor for moving the battery engaging portion 124 and an operation motor for operating the robot 1. The motor 144 is connected to the control unit, and the control unit controls the motor 144.

In the robot 1 shown in FIG. 14 and the like, when the battery 103 is inserted into the battery housing portion 104, the lock member 111 urged inward in the left-right direction by the urging member must be moved outward in the left-right direction. Further, the urging member 112 contacts the back end surface of the battery 103 and urges the battery 103 toward the front side of the battery housing portion 104. Therefore, in this robot 1, the absolute value of the torque required for the motor 144 when the battery engaging portion 124 inserts the battery 103 into the battery housing portion 104 becomes large, and the battery engaging portion 124 moves from the battery housing portion 104 to the battery. The absolute value of the torque required for the motor 144 when pulling out 103 becomes small. In other words, the maximum absolute value of the torque required for the motor 144 when the motor 144 rotates in one direction into which the battery 103 is inserted is required for the motor 144 when the motor 144 rotates in the other direction in which the battery 103 is pulled out. It becomes larger than the maximum absolute value of torque.

Therefore, in the robot 1 shown in FIG. 14 and the like, the absolute value of the second torque limit value, which is the torque limit value of the motor 144 when the battery 103 is pulled out, is the torque limit value of the motor 144 when the battery 103 is inserted. The first torque limit value and the second torque limit value are set so as to be smaller than the absolute value of the one torque limit value. Specifically, when the battery engaging portion 124 normally performs the insertion operation and the extraction operation of the battery 103, the torque of the motor 144 exceeds the first torque limit value or falls below the second torque limit value. In addition, the torque of the motor 144 exceeds the first torque limit value when the battery 103, the battery engaging portion 124, etc. come into contact with the peripheral device when the battery 103 is inserted, and the battery 103 is removed when the battery 103 is pulled out. The first torque limit value and the second torque limit value are set so that the torque of the motor 144 is less than the second torque limit value when 103, the battery engaging portion 124, etc. come into contact with the peripheral device or the like. Further, when the battery 103 is inserted, the motor 144 is controlled based on the first torque limit value, and when the battery 103 is pulled out, the motor 144 is controlled based on the second torque limit value.

Therefore, in this robot 1, when the battery engaging part 124 or the like comes into contact with a peripheral device or the like when the battery 103 is replaced and the torque of the motor 144 exceeds or falls below the torque limit value, the robot 144 is stopped. It becomes possible to prevent damage to the battery engaging portion 124 and the like. In addition, in the robot 1, when the battery engaging portion 124 is operating normally when the battery 103 is replaced, the battery engaging portion 124 can be appropriately operated by continuing to rotate the motor 144. .

[Modification 4 of industrial robot]
FIG. 19 is a perspective view of an industrial robot 1 according to another embodiment of the present invention. FIG. 20 is a perspective view of an industrial robot 1 according to another embodiment of the present invention.

The robot 1 to which the present invention is applied may be a robot other than a horizontal articulated robot or a battery exchange robot. For example, the robot 1 to which the present invention is applied may be a vertical articulated robot having a plurality of joint portions as shown in FIG. The robot 1 includes a base frame 202 fixed to a predetermined installation surface, a turning frame 203 rotatably connected to the base frame 202, and a first arm 204 rotatably connected to the turning frame 203. The second arm 205 is rotatably connected to the first arm 204, and the wrist 206 is rotatably connected to the second arm 205.

The base end side of the first arm 204 is connected to the turning frame 203 so as to be able to turn around the axis A1. A motor 214 that rotates the first arm 204 with respect to the turning frame 203 is disposed at a joint portion 213 that connects the turning frame 203 and the first arm 204. The proximal end side of the second arm 205 is connected to the distal end side of the first arm 204 so as to be rotatable about the axis A2. A motor 216 that rotates the second arm 205 with respect to the first arm 204 is disposed at a joint portion 215 that connects the first arm 204 and the second arm 205. In the following description, the clockwise rotation direction in FIG. 19 is the clockwise direction, and the counterclockwise rotation direction in FIG. 19 is the counterclockwise direction.

The maximum absolute value of the torque required for the motor 214 when the first arm 204 rotates clockwise with respect to the turning frame 203 due to the influence of the weight of the second arm 205 and the wrist 206 is the first value. When one arm 204 rotates counterclockwise with respect to the revolving frame 203, the robot 1 rotates so that the first arm 204 rotates within a range that is larger than the maximum absolute value of the torque required for the motor 214. Is used, the absolute value of the second torque limit value, which is the torque limit value of the motor 214 when the first arm 204 rotates counterclockwise, is the first arm 204 rotates clockwise. The first torque limit value and the second torque limit value are set so as to be smaller than the absolute value of the first torque limit value that is the torque limit value of the motor 214 at the time. When the first arm 204 rotates clockwise, the motor 214 is controlled based on the first torque limit value, and when the first arm 204 rotates counterclockwise, based on the second torque limit value. Thus, the motor 214 is controlled.

Also, the maximum value of the absolute value of the torque required for the motor 216 when the second arm 205 rotates clockwise relative to the first arm 204 due to the weight of the wrist portion 206 and the like is the second arm. When the robot 205 rotates counterclockwise with respect to the first arm 204, the robot 1 rotates so that the second arm 205 rotates within a range that is larger than the maximum absolute value of the torque required for the motor 216. When used, the absolute value of the second torque limit value that is the torque limit value of the motor 216 when the second arm 205 rotates counterclockwise is the second arm 205 rotates clockwise. The first torque limit value and the second torque limit value are set so as to be smaller than the absolute value of the first torque limit value that is the torque limit value of the motor 216 at that time. When the second arm 205 rotates clockwise, the motor 216 is controlled based on the first torque limit value, and when the second arm 205 rotates counterclockwise, based on the second torque limit value. Thus, the motor 216 is controlled.

Also in this case, similarly to the above-described embodiment, when the wrist portion 206 or the like comes into contact with the peripheral device or the like during the operation of the first arm 204 or the second arm 205, the

motors

214 and 216 are stopped and the wrist portion 206 is stopped. It is possible to prevent the damage of the robot 1 and the like, and when the first arm 204 and the second arm 205 are operating normally, the

motors

214 and 216 are continuously rotated to operate the robot 1 appropriately. Is possible. In the robot 1 shown in FIG. 19, the

motors

214 and 216 are operating motors. The

motors

214 and 216 are connected to the control unit, and the control unit controls the

motors

214 and 216.

Further, the robot 1 to which the present invention is applied may be a so-called parallel link type robot as shown in FIG. The robot 1 includes a main body 252, three levers 253 connected to the main body 252, an arm 254 connected to each of the three levers 253, and a head unit 255 connected to the arm 254. And. The three levers 253 are connected to the main body portion 252 so as to extend radially at substantially equal angular pitches toward the outer periphery of the main body portion 252. The base end sides of the three levers 253 are rotatably connected to the main body 252. A motor 258 that rotates the lever 253 is disposed at a joint 257 that connects the main body 252 and the lever 253. The proximal end side of the arm portion 254 is rotatably connected to the distal end side of the lever 253. The head unit 255 is rotatably connected to the distal end side of the arm portion 254.

In the robot 1 shown in FIG. 20, the maximum absolute value of the torque required for the motor 258 when the lever 253 rotates in one direction due to the weight of the head unit 255 and the like is such that the lever 253 is in the other direction. When the robot 1 is used so that the lever 253 rotates within a range that is larger than the maximum absolute value of the torque required for the motor 258 when rotating, the lever 253 rotates in the other direction. The absolute value of the second torque limit value, which is the torque limit value of the motor 258, is greater than the absolute value of the first torque limit value, which is the torque limit value of the motor 258 when the lever 253 rotates in one direction. The first torque limit value and the second torque limit value are set so as to decrease. Further, when the lever 253 rotates in one direction, the motor 258 is controlled based on the first torque limit value, and when the lever 253 rotates in the other direction, the motor 258 is controlled based on the second torque limit value. Is done.

Also in this case, similarly to the above-described embodiment, when the head unit 255 or the like comes into contact with the peripheral device or the like during the operation of the lever 253 and the arm 254, the motor 258 is stopped to prevent the head unit 255 or the like from being damaged. In addition, when the lever 253 and the arm 254 are operating normally, it is possible to continue the rotation of the motor 258 and operate the robot 1 appropriately. In the robot 1 shown in FIG. 20, the motor 258 is a motor for operation. The motor 258 is connected to the control unit, and the control unit controls the motor 258.

The robot to which the present invention is applied may be other types of robots. For example, the robot to which the present invention is applied may be an orthogonal type robot.

1 Robot (industrial robot)
2 Main unit 5 Control unit 6 Pendant switch 11 First arm unit 12 Second arm unit 15 Motor (first rotation motor)
17 Motor (second rotation motor)
19 Motor (Rotary motor)
22, 61, 86 Motor (lifting motor)
23 Ball screw spline shaft (end effector mounting member)
43, 53, 73 Hand (end effector)
44, 54, 74 Arm (end effector mounting member)
77 Case body 79 Hollow rotating shaft (part of shaft member)
81 Holding member (part of shaft member)
84 Bellows 102 Vehicle 103 Battery 104 Battery receiving portion 117 Battery insertion / removal mechanism 124 Battery engagement portion 144 Motor (Pull-out / insertion motor)
214, 216, 258 Motor T1 to T4, T13, T14 Torque limit value T11 First torque limit value (torque limit value)
T12 Second torque limit value (torque limit value)
T21 First torque limit value, first torque limit value during teaching T22 Second torque limit value, second torque limit value during teaching T23 First torque limit value, first torque limit value during automatic operation T24 Second torque Limit value, second torque limit value during automatic operation

Claims

In an industrial robot comprising an operation motor and a control unit for controlling the motor,
The torque of the motor for rotating the motor in one direction is a positive torque, the torque of the motor for rotating the motor in the other direction is a negative torque, and after the teaching of the industrial robot is finished The automatic operation of the industrial robot performed to confirm whether the teaching point and / or the control program of the industrial robot is correct is set as a test operation, and the automatic operation of the industrial robot performed after the test operation is normally performed. When driving
The control unit rotates the motor at a rotation speed lower than the rotation speed during the normal operation during the test operation, and when the motor rotates in one direction during the test operation, If the motor is controlled with a torque limit value lower than the torque limit value when the motor rotates in one direction, and the motor rotates in the other direction during the test operation, the motor during the normal operation An industrial robot characterized in that the motor is controlled with a torque limit value that is higher than a torque limit value when the motor rotates in the other direction.
As the motor, equipped with a lifting motor for lifting the end effector,
During the test operation, the torque limit value of the lifting motor when the end effector is raised is the first torque limit value, and the torque limit value of the lifting motor when the end effector is lowered is the second torque. As a limit value,
In the control unit, the first torque limit value and the second torque limit value are set so that the absolute value of the second torque limit value is smaller than the absolute value of the first torque limit value,
The control unit controls the lift motor based on the first torque limit value when the end effector is raised during the test operation, and the second torque when the end effector is lowered during the test operation. 2. The industrial robot according to claim 1, wherein the lift motor is controlled based on a limit value.
A pendant switch electrically connected to the control unit;
A motor load including at least one of the weight of the end effector and the weight of the work held by the end effector can be input from the pendant switch.
The industrial robot according to claim 2, wherein the controller sets the first torque limit value and the second torque limit value based on the motor load input from the pendant switch.
A main body portion, a first arm portion whose base end side is rotatably connected to the main body portion, and a second arm portion whose base end side is rotatably connected to the distal end side of the first arm portion; And an end effector disposed on the distal end side of the second arm portion,
As the motor, a first rotation motor for rotating the first arm portion with respect to the main body portion, and a second time for rotating the second arm portion with respect to the first arm portion. A motor for rotation, a motor for rotation for rotating the end effector relative to the second arm portion, and a motor for lifting and lowering the end effector relative to the second arm portion. The industrial robot according to any one of claims 1 to 3.
A main body portion, a first arm portion whose base end side is rotatably connected to the main body portion, and a second arm portion whose base end side is rotatably connected to the distal end side of the first arm portion; , An end effector disposed on the distal end side of the second arm portion, a first rotating motor for rotating the first arm portion with respect to the main body portion, and the first arm portion with respect to the first arm portion. A second rotation motor for rotating the second arm portion and a rotation motor for rotating the end effector relative to the second arm portion;
The motor includes a lifting motor for lifting the end effector with respect to the second arm portion,
The control unit rotates the first rotation motor, the second rotation motor, and the rotation motor at the same speed as the rotation speed during the normal operation during the test operation, and during the normal operation. Is controlled at the same torque limit value as the torque limit value, and during the test operation, the lift motor is rotated at a rotation speed lower than the rotation speed during the normal operation. When rotating in the direction, the elevator motor is controlled with a torque limit value lower than the torque limit value when the elevator motor rotates in one direction during the normal operation, and the elevator motor is controlled during the test operation. When the motor for rotation is rotated in the other direction, the motor for lifting / lowering is performed with a torque limit value higher than the torque limit value for when the motor for lifting / lowering rotates in the other direction during the normal operation. Industrial robot according to any one of claims 1 to 3, characterized in that to control.
The industrial robot according to any one of claims 1 to 5, wherein the controller can select a rotation speed and a torque limit value of the motor during the test operation.
A method for controlling an industrial robot including a motor for operation,
The torque of the motor for rotating the motor in one direction is a positive torque, the torque of the motor for rotating the motor in the other direction is a negative torque, and after the teaching of the industrial robot is finished The automatic operation of the industrial robot performed to confirm whether the teaching point and / or the control program of the industrial robot is correct is set as a test operation, and the automatic operation of the industrial robot performed after the test operation is normally performed. When driving
During the test operation, the motor is rotated at a rotation speed lower than the rotation speed during the normal operation, and when the motor rotates in one direction during the test operation, the motor rotates in one direction during the normal operation. When the motor is controlled with a torque limit value lower than the torque limit value when rotating in the normal direction, and the motor rotates in the other direction during the test operation, the motor rotates in the other direction during the normal operation. A control method for an industrial robot, wherein the motor is controlled with a torque limit value higher than a torque limit value in the case of performing.
An operation motor, and a control unit for controlling the motor,
The maximum absolute value of torque required for the motor when the motor rotates in one direction is greater than the maximum absolute value of torque required for the motor when the motor rotates in the other direction. It ’s getting bigger,
When the torque limit value of the motor when rotating in one direction is the first torque limit value, and the torque limit value of the motor when rotating in the other direction is the second torque limit value,
In the control unit, the first torque limit value and the second torque limit value are set so that the absolute value of the second torque limit value is smaller than the absolute value of the first torque limit value,
The controller controls the motor based on the first torque limit value when the motor rotates in one direction, and based on the second torque limit value when the motor rotates in the other direction. An industrial robot characterized by controlling the motor.
The industrial robot is disposed in the atmosphere,
The motor is a lifting motor for lifting the end effector,
The end effector rises when the motor rotates in one direction, and the end effector descends when the motor rotates in the other direction,
The first torque limit value is a torque limit value of the motor when the end effector is raised, and the second torque limit value is a torque limit value of the motor when the end effector is lowered,
The controller controls the motor based on the first torque limit value when the end effector is raised, and controls the lift motor based on the second torque limit value when the end effector is lowered. The industrial robot according to claim 8.
A pendant switch electrically connected to the control unit;
A motor load including at least one of the weight of the end effector and the weight of the work held by the end effector can be input from the pendant switch.
The industrial robot according to claim 9, wherein the controller sets the first torque limit value and the second torque limit value based on the motor load input from the pendant switch.
The control unit drives the motor to acquire a motor load of the motor, and sets the first torque limit value and the second torque limit value based on the acquired motor load. The industrial robot according to claim 8 or 9.
In the control unit, the first torque limit value and the second torque limit value according to the motor load are tabulated and stored.
The industrial robot according to claim 10 or 11, wherein the controller reads and sets the corresponding first torque limit value and the second torque limit value based on the motor load.
The control unit controls at least the motor based on the first torque limit value when the end effector ascends when teaching the industrial robot, and controls the end effector when teaching the industrial robot. The industrial robot according to claim 9, wherein the motor is controlled based on the second torque limit value when descending.
The control unit controls the motor based on the first torque limit value when the end effector is raised during automatic operation of the industrial robot after teaching is completed, and the end effector during the automatic operation is controlled. Controlling the motor based on the second torque limit value when descending;
The first torque limit value at the time of teaching is different from the first torque limit value at the time of automatic operation,
The industrial robot according to claim 13, wherein the second torque limit value at the time of teaching is different from the second torque limit value at the time of automatic operation.
An end effector mounting member to which the end effector is mounted;
The industrial robot according to claim 9, wherein the motor moves the end effector and the end effector mounting member up and down.
An end effector, an end effector mounting member to which the end effector is mounted, a shaft member that is arranged with the vertical direction as an axial direction and the end effector mounting member is fixed to the upper end, and a case in which at least the lower end side of the shaft member is accommodated A body, and a bellows arranged at one end to be fixed to the case body and the other end fixed to the shaft member and to cover the outer peripheral side of the shaft member,
The motor is an elevating motor for elevating the end effector, the end effector mounting member and the shaft member with respect to the case body,
The end effector and the end effector mounting member are disposed in a vacuum,
Either one of the inner peripheral side and the outer peripheral side of the bellows is in a vacuum, and the other of the inner peripheral side and the outer peripheral side of the bellows is at atmospheric pressure,
When the motor rotates in one direction, the end effector is lowered, and when the motor is rotated in the other direction, the end effector is raised,
The first torque limit value is a torque limit value of the motor when the end effector is lowered, and the second torque limit value is a torque limit value of the motor when the end effector is raised,
The controller controls the motor based on the first torque limit value when the end effector is lowered, and controls the lift motor based on the second torque limit value when the end effector is raised. The industrial robot according to claim 8.
The industrial robot is a battery exchange robot provided with a battery insertion / removal mechanism that is attached to a vehicle and that pulls out the battery from a battery housing portion in which a battery is housed and inserts the battery into the battery housing portion,
The battery insertion / removal mechanism includes a battery engaging portion that engages with the battery,
The motor is a pull-in / out motor for moving the battery engaging portion,
When the motor rotates in one direction, the battery engaging portion inserts the battery into the battery housing portion, and when the motor rotates in the other direction, the battery engaging portion removes the battery from the battery housing portion. Pull out,
The first torque limit value is a torque limit value of the motor when the battery engaging portion inserts the battery into the battery housing portion, and the second torque limit value is determined by the battery engaging portion. It is a torque limit value of the motor when the battery is pulled out from the accommodating portion,
The control unit controls the motor based on the first torque limit value when the battery is inserted, and controls the lifting motor based on the second torque limit value when the battery is pulled out. The industrial robot according to claim 8.
A method for controlling an industrial robot including a motor for operation,
The maximum absolute value of torque required for the motor when the motor rotates in one direction is greater than the maximum absolute value of torque required for the motor when the motor rotates in the other direction. It ’s getting bigger,
When the torque limit value of the motor when rotating in one direction is the first torque limit value and the torque limit value of the motor when rotating in the other direction is the second torque limit value, the second torque limit value The first torque limit value and the second torque limit value are set such that the absolute value is smaller than the absolute value of the first torque limit value;
When the motor rotates in one direction, the motor is controlled based on the first torque limit value, and when the motor rotates in the other direction, the motor is controlled based on the second torque limit value. An industrial robot control method comprising:
The industrial robot is disposed in the atmosphere,
The motor is a lifting motor for lifting the end effector,
The end effector rises when the motor rotates in one direction, and the end effector descends when the motor rotates in the other direction,
The first torque limit value is a torque limit value of the motor when the end effector is raised, and the second torque limit value is a torque limit value of the motor when the end effector is lowered,
When the end effector is raised, the motor is controlled based on the first torque limit value, and when the end effector is lowered, the lift motor is controlled based on the second torque limit value. The method for controlling an industrial robot according to claim 18.