JPH0740269A - Industrial robot origin adjusting method and device therefor - Google Patents

Abstract

PURPOSE:To accurately performed positional control without complicating computation processing by suitably performing the origin adjustment estimating the deviation of the origin when the origin is deviated cauased by the positional deviation of a robot. CONSTITUTION:Deviation amount according to the origin shift amount is previously stored in a storage means 18, moreover a reference point is set in the specific position within the robot shaft operation range, and a motor 5 is driven according to the origin returning command by a control means 12, so as to start the origin returning. After that, the origin returning state is made by operating the motor to the position where a zero signal is output from an encoder 6 near the reference point. At that time, the deviation amount is given as a reset value to the position counter 11 for counting the output of the encoder 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a device for adjusting an origin in a robot which performs position control based on an output of an encoder which detects a driving amount of a driving means for a robot axis.

[0002]

2. Description of the Related Art Conventionally generally known industrial robots are equipped with robot axes such as rotary joint axes and translation axes and servo motors and pulse motors as drive means, and measure encoders and their outputs. The position is detected using a position counter or the like, and the motor is controlled accordingly.

By the way, in order to determine the absolute position of the current position of the robot axis when the power is turned off and then turned on again, it is necessary to check the origin position by an operation called origin return. .

As this operation, first, the motor is driven so as to move the robot axis in the direction of the origin, and is moved to a predetermined reference point (fixed point) for origin setting. The reference point is determined by disposing a proximity sensor or the like, or by the moving end on the mechanism. Further, since the encoder that detects the current position of the motor usually has a function of outputting a signal (a so-called zero signal) indicating the rotation reference position for each rotation of the motor, the encoder continues to move to the reference point. The position near the reference point is moved to a position where the signal indicating the rotation reference position is output from the encoder, and this state is set to the origin return state. Then, in this return-to-origin state, the value of the position counter is cleared to zero.

By doing so, in the subsequent control,
A position based on the origin is detected based on the measurement of the position counter. Then, the motor is controlled based on the comparison between the detected position and the position given by the position command generating means, whereby the robot axis is operated up to the teaching point (final target position).

[0006]

By the way, since the industrial robot is generally used under severe conditions, the robot axis may be displaced due to some external force. If such a situation occurs, just by examining the origin by the conventional method as described above, the apparent origin position, which is the position in the origin return state, deviates from the original origin position, and therefore, In the position control of 1), the teaching point is not correctly operated and an error occurs. In particular, in the case of a horizontal joint type robot having a rotary joint axis, if the origin deviation as described above occurs due to the procedure of converting the amount of rotation of the joint into the Cartesian coordinate system, this should be adjusted by the coordinate value. Is impossible. Therefore, there is a method of adding and subtracting the deviation of the origin each time before converting the rotation amount of the joint to the Cartesian coordinate system. According to this method, it is necessary to calculate Since we have to add and subtract,
There is a problem that the burden of calculation processing is heavy.

Further, in an orthogonal robot or the like, there may be a demand for shifting the orthogonal coordinate system for convenience according to the situation when the robot is used. In other words, depending on the work content and the like, it may be more convenient to perform control assuming a temporary coordinate system shifted from the original coordinate system. However, even in such a case, conventionally, the shift amount of the coordinate system has to be added and subtracted each time when calculating all position quantities, which increases the load of the calculation process.

Another problem is that, in general, the origin return operation cannot be performed while anticipating the position of the reference point, resulting in a considerably slow speed, which is far from the origin position in a robot having a large robot axis working range. It takes a long time to perform home return from the position, resulting in poor work efficiency.

In view of the above circumstances, the present invention appropriately adjusts the origin when the origin is displaced due to the displacement of the robot axis or when the coordinate system is to be shifted for the sake of convenience. An object of the present invention is to enable position control to be accurately performed without complicating arithmetic processing. Another purpose is to reduce the time required for the origin return operation.

[0010]

A first aspect of the present invention relates to a method for adjusting the origin of an industrial robot, which is a robot axis formed of a rotary joint axis or a translation axis, and driving means for driving the robot axis. An encoder that outputs a signal that detects the drive amount of the drive unit and a rotation reference position signal that indicates the rotation reference position for each rotation of the drive unit, and a measurement unit that performs position detection based on the measurement of the output of the encoder. In an industrial robot having a reference point for defining an origin at a predetermined position within the operating range of the robot axis, the robot axis is operated toward the reference point side by the driving means, and the reference point is set. After performing a home-return operation that operates the robot axis to a position where the rotation reference position signal is generated in the vicinity, the measurement means returns the home-return movement to a predetermined deviation amount. In which it was to give as a reset value at the time of the end.

A second aspect of the present invention relates to an apparatus for observing the method of the first aspect of the invention, which is a robot axis composed of a rotary joint axis or a translation axis, drive means for driving the robot axis, and the drive. An encoder that outputs a signal for detecting the drive amount of the drive unit and a rotation reference position signal that indicates the rotation reference position for each rotation of the drive unit; and a measurement unit that performs position detection based on the measurement of the output of the encoder. In an industrial robot in which a reference point for defining an origin is set at a predetermined position within the operating range of the robot axis, the robot axis is operated by the driving means in response to an origin return command signal, and the reference point of the reference point is changed. By performing the determination and the determination of the rotation reference position signal, the origin return operation of the robot axis is performed up to the position where the rotation reference position signal occurs near the reference point. Control means, a storage means for storing a deviation amount corresponding to the origin shift amount according to the origin shift factor, and a deviation amount read from the storage means when the robot axis origin return operation by the control means is performed. The measuring means is provided with a deviation amount transferring means which is given as a reset value.

A third invention is an invention relating to a method of adjusting an origin of an industrial robot, which comprises a robot axis composed of a rotary joint axis or a translation axis, a driving means for driving the robot axis, and a driving amount of the driving means. And a encoder for outputting a rotation reference position signal indicating a rotation reference position for each rotation of the drive means, and a measurement means for performing position detection based on measurement of the output of the encoder,
In an industrial robot in which a reference point for defining an origin is set at a predetermined position within the operating range of the robot axis, a plurality of reference points are set at predetermined intervals within the operating range of the robot axis in advance, and The robot axis is operated in a predetermined direction by the driving means, and the origin return operation is performed to operate the robot axis until the rotation reference position signal is generated near the reference point close to the operation start point. The deviation amount according to the reference point is given to the means as a reset value at the end of the origin return operation.

A fourth aspect of the present invention relates to an apparatus for observing the method of the third aspect of the present invention, which is a robot shaft formed of a rotary joint shaft or a translation shaft, drive means for driving the robot shaft, and the drive. An encoder that outputs a signal for detecting the drive amount of the drive unit and a rotation reference position signal that indicates the rotation reference position for each rotation of the drive unit; and a measurement unit that performs position detection based on the measurement of the output of the encoder. In an industrial robot in which a reference point for defining an origin is set at a predetermined position within the operating range of the robot axis, a plurality of reference points at predetermined intervals within the operating range of the robot axis are detected. In accordance with the reference point sensor, the identification means for identifying each reference point sensor, and the return-to-origin command signal,
The signal from the reference point sensor and the encoder is read while driving the driving means, and the origin of the robot axis is reached to a position where the rotation reference position signal is generated in the vicinity of any one of the plurality of reference points. Control means for performing the return operation, storage means for storing the deviation amount from the origin equivalent position for each reference point, and identification by the identification means when the origin return operation of the robot axis by the control means is performed. Based on the deviation amount, a deviation amount transfer means for reading the deviation amount of the corresponding reference point from the storage means and giving it to the measuring means as a reset value is provided.

[0014]

According to the method of the first aspect of the invention and the apparatus of the second aspect of the invention, when the apparent origin is shifted due to the displacement of the robot axis or the like, the corresponding deviation amount is given to the measuring means at the time of returning to the origin. As a result, the adjustment of the origin shift is achieved at this stage, and in the subsequent position control, correct position detection is performed without requiring complicated calculation processing. Further, even when a coordinate system in which the origin is shifted is assumed for the sake of convenience, the adjustment according to the coordinate system is achieved at the stage of returning to the origin.

According to the method of the third aspect of the invention and the apparatus of the fourth aspect of the invention, the origin return operation is performed up to the reference point near the position at the start of origin return among the plurality of reference points. Since the origin adjustment is achieved by providing the measuring means with the deviation amount according to the above, the moving distance in the origin returning operation can be short, and the time required for the origin returning operation can be shortened.

[0016]

Embodiments of the present invention will be described with reference to the drawings.

1 to 4 show a first embodiment.
The industrial robot shown in FIG. 1 is a horizontal joint type robot (so-called SCARA type robot) having a plurality of rotary joint axes as robot axes, and includes a main body 1, a first arm 2A and a second arm 2A.
The arm 2B and the head unit 3 are provided. The first arm 2A is pivotable with respect to the main body 1 by being connected to a first rotary joint shaft 4A that is rotatably supported by the main body 1 at a base end portion thereof. Arm 2B
Is a second arm rotatably supported on the tip of the first arm 2A.
By connecting the base end to the rotary joint shaft 4B, the first
It is capable of turning with respect to the arm 2A. The head portion 3 is mounted on the tip of the second arm 2B,
The arm 2B has a support shaft 3a that can be raised and lowered and rotated, and a working member 3b such as an air chuck is attached to the lower end of the support shaft 3a.

A first arm driving motor 5A and a second arm driving motor 5B are provided as driving means for driving the first and second arms 2A and 2B, and the rotary joints are formed by these motors 5A and 5B. When the shafts 4A and 4B are turned, the arms 2A and 2B turn. Encoders 6A and 6B for detecting the rotational drive amounts of the motors 5A and 5B are provided. Further, a reference point for setting the origin at a predetermined position within the operating range of the rotary joint shafts 4A, 4B (that is, within the swing range of the arms 2A, 2B) is set, and for example, the reference point is set approximately at the center of the arm swing range. Is set, and the reference point sensors 7A and 7B for detecting the reference points are set to the rotary joint axes 4A and 4A, respectively.
It is provided for B. This reference point sensor 7A, 7
B is composed of, for example, a proximity switch or the like.

The signals from the encoders 6A and 6B and the reference point sensors 7A and 7B are transmitted to a control unit 10 such as a computer via a signal line, a connector and the like. The control unit 10 controls the driving of the motors 5A and 5B.

Further, in this robot, the head portion 3
A Z-axis servomotor 8 and an R-axis servomotor 9 for raising and lowering and rotating the support shaft 3a are provided, and these are also controlled by the control unit 10.

FIG. 2 shows a robot axis control system including an origin adjusting device. This control system is used in a SCARA robot as shown in FIG. 1 for its first arm 2A and second arm 2A.
The motor 5 in FIG. 1 corresponds to the first arm driving motor 5A or the second arm driving motor 5B in FIG. 1, and the encoder 6 in FIG. Of the encoder 6A or 6B. The encoder 6 outputs a pulse signal as a signal for detecting the drive amount of the motor 5, and also outputs a zero signal which is a signal indicating a rotation reference position for each rotation of the motor 5.

In this figure, the control unit 10
Has a position counter (measuring means) 11 for measuring the position by counting the pulse signals of the encoder 6, and also has a control means 12 for controlling the motor 5, and at a target position when driving the motor. It has a position command generating means 13 for generating a corresponding position command and giving the command signal to the control means 12. Further, for the origin adjustment, the origin return command generating means 14 and the reference point determining means 1
The control unit 10 includes 5, an origin return determination unit 16, a deviation amount changing unit 17, a deviation amount storage unit 18, and a deviation amount transfer unit 19.

In the normal position control, the control means 12 is similar to the general robot control in the position command generating means 1.
The motor 5 is controlled based on the comparison between the output of No. 3 and the signal given from the encoder 6 via the position counter 11. In addition to this, the origin return command is generated in response to the power-on or the operation for the origin return command. When the return-to-origin command signal is given from the means 14, the motor 5 is driven so as to move the robot axis to the reference point side. Further, the reference point determination means 15 is configured to start the motor drive in response to the origin return command,
Based on the signals from the reference point sensors 7A and 7B, it is determined whether or not the reference point is reached. The origin return determination means 16 determines the presence or absence of a zero signal from the encoder 6 after the determination of the reference point. Then, based on these determinations, the zero signal is not transmitted to the encoder 6 until the reference point is passed.
Is returned to the origin, and the origin return operation is performed such that the motor 5 is driven up to this state.

Further, the deviation amount transfer means 19 transfers the deviation amount stored in the deviation amount storage means 18 to the position counter 11 when the origin return state is reached.
The deviation amount corresponds to an origin shift amount according to a origin shift factor such as a positional deviation of a robot axis, which will be described later, and is determined by the deviation amount changing means 17 before the origin returning operation is performed. It is stored in the deviation amount storage means 18.

FIG. 3 is a flow chart showing an origin adjusting method by the apparatus shown in FIG. When this flow chart starts, it is determined whether or not the home-return control should be performed by checking the presence or absence of the home-return command signal (step S1). If the determination is YES, the robot axis is moved toward the reference point. Motor 5 to work
Is driven (step S2). Then, it is determined whether or not the reference point is reached (step S3), and when the reference point is reached, the motor 5 is continuously driven (step S3).
4) It is determined whether or not there is a zero signal from the encoder 6 (step S5). When there is the zero signal, the deviation amount stored in the deviation amount storage means 18 is read out and transferred to the position counter 11 (step S).
6). In this way, the return-to-origin is completed, and when the return-to-origin is completed, the deviation amount is given to the position counter 11 as a reset value.

If the determination in step S1 is NO, normal position control is performed (step S6). In this case, the above-described deviation amount is given to the position counter 11 in the control of the origin return before that, and the pulse of the encoder 6 is counted with this as an initial value to obtain the position in consideration of the origin shift, The motor 5 is controlled based on the comparison between this and the output of the position command generating means 13.

A specific example of the origin shift factor and the method of obtaining the deviation amount according to the origin shift factor will be described with reference to FIGS. Figure 4
(A) shows the original point return state at the beginning when no displacement of the robot axis has occurred, and PO is the position of the head portion at this time (position corresponding to the original point). Further, FIG. 4B shows a return-to-origin state after some external force is applied to cause a positional deviation in the rotation direction of the robot axis, which is different from the initial state due to the positional deviation of the robot axis that causes the origin shift. The arms 2A and 2B are angularly displaced (deviation angles θ1 and θ2), and the position of the head portion (apparent origin position) PO ′ is shifted. This is because the rotation angle from the position of the reference point to the position where the zero signal of the encoder 6 is output changes in the above-described origin return operation.
Actually, the origin does not always return to the ideal linear state as shown in FIG. 4A even at the beginning, and even if the robot axis is displaced, it is as large as shown in FIG. 4B. Although the origin shift does not occur, the figure is exaggerated for clarity.

The coordinate values of the joint rotation system when the head portion is moved to a predetermined fixed point P1 as shown in FIG. 4 (c) are measured before and after the occurrence of the positional deviation, and the respective coordinates are measured. Comparing the values, since the coordinate values are different by the amount of the origin shift before and after the positional deviation occurs, each arm 2A in the state in FIG. 4B is different from the state in FIG. 4A. The deviation angles θ1 and θ2 of 2B are obtained.

The deviation amount is obtained in this way, and the deviation amount is changed by performing such processing again after an appropriate period. The deviation amount is stored in the deviation amount storage means 18.

According to this embodiment, when an origin shift occurs in which the apparent origin is displaced from the true origin (original origin) due to the displacement of the robot axis, the deviation amount corresponding to the origin shift amount is returned to the origin. The position is given to the position counter 11 at the time of completion of the operation, and this is used as the initial value of the position counter 11 in the subsequent position control, so that the position based on the true origin is correctly obtained. Moreover, it is not necessary to add or subtract the shift amount for each position detection and calculation process repeated during the position control, and the process of obtaining the position based on the output of the position counter 11 is simplified.

FIG. 5 shows a second embodiment in which the robot type and origin shift factor are different. The robot shown in this figure is an orthogonal two-axis robot having an X axis and a Y axis as robot axes, and includes a first member 21 extending in the X axis direction and a Y member.
A second member 22 extending in the axial direction and connected to the first member 21 so as to be movable in the X-axis direction; and a head portion 23 attached to the second member 22 so as to be movable in the Y-axis direction. And a working member is attached to the head portion 23. Then, the X-axis servo motor 25 is used as a driving unit.
It has A and Y axis servo motors 25B, and while the X axis servo motor 25A moves the second member 22 with respect to the first member 21 via a ball screw or the like,
The head portion 23 is moved with respect to the second member 22 via a ball screw or the like by the Y-axis servomotor 25B.

Encoders 26A and 26A for detecting the rotational drive amount of the servo motors 25A and 25B, respectively.
26B is provided. Further, a reference point for setting the origin is set at a predetermined position within the robot operation range. For example, the reference points are set at the positions of the moving ends on one end side in the X-axis direction and one end side in the Y-axis direction. Therefore, the position where the zero signal is output from the encoders 26A and 26B near the reference point is the origin O.

As the origin shift factor, it may be required to shift the Cartesian coordinate system for convenience according to the situation when the robot is used, and O'is the hypothesized origin in such a case. is there.

Also in the second embodiment, the origin adjustment can be performed by directly applying the control system shown in FIG. 2 and the method shown in the flowchart of FIG. That is, when there is a return-to-origin command, the control unit 12 causes the motor (servo motor) to move the movable portion to the reference point side.
Is driven, the reference point is determined by the reference point determination means 15, for example, by checking that the movement end has been reached, and further, based on the determination by the origin return determination means 16, the encoder 6 closes to zero near the reference point. The motor 5 is driven until the signal returns to the home-return state. And
In this return-to-origin state, the deviation amount transfer means 19 reads the deviation amount from the deviation amount storage means 18, and the position counter 1
1 is given as a reset value.

The above-mentioned deviation amount is obtained in advance before the origin return control and is stored in the deviation amount storage means 18. in this case,
In this embodiment, the deviation amount is the shift amount of the intentionally defined hypothetical origin from the true origin.

According to this embodiment, during normal robot control that is performed after the return-to-origin control, the position counter 11 counts the pulses of the encoder 6 with the deviation amount corresponding to the above-mentioned assumed shift of the origin as the initial value. Be seen. Therefore,
For the sake of convenience, robot control can be performed based on the assumed origin. Moreover, it is not necessary to add or subtract the shift amount for each calculation process, and the process of obtaining the position with the assumed origin as a reference becomes simple.

6 to 8 show a third embodiment.
In this embodiment, a plurality of reference points Q0, Q1, Q2, Q3 are set in order to shorten the time required for the home-return operation. That is, as shown in FIG. 6, within the operating range of the robot axis 30, in addition to the reference point Q0 corresponding to the original origin,
One to a plurality of auxiliary reference points Q1, Q2, Q3 are set at predetermined intervals, and the respective reference points Q0, Q1, Q2, Q are set.
3, the reference point sensors 31A, 31B, 31C, 31D are arranged, and the reference point sensors 31A, 31B, 31
Identification sensors 32A, 32B, 32 for identifying C and 31D
C and 32D are arranged. Each reference point Q0, Q1, Q
The interval between 2 and Q3 is set to an integral multiple of a so-called lead value (movement amount per one rotation of the motor) of a mechanism such as a ball screw. Reference numeral 33 is a movable part which moves by the operation of the robot axis.

In FIG. 7 showing the control system of the third embodiment, a motor 35 as a robot driving means, an encoder 36, a position counter 41, a control means 42, an origin return command generating means 44, a reference point discriminating means 45 and The return-to-origin determination means 46 is configured substantially the same as that shown in FIG. However, the reference point discriminating means 45 discriminates one of the reference point sensors 31A, 31B, 31C and 31D when it is turned on.
Therefore, when the home-return operation is performed, the drive of the motor 35 is started in response to the home-return command, and then the reference points Q0, A position where the zero signal is output from the encoder 36 near any one of Q1, Q2, and Q3 is set as a temporary origin, and a state in which the movable portion 33 reaches the temporary origin is set as a home-return state.

Further, the identification sensor discriminating means 47 for discriminating which of the reference points the movable portion 33 is located in the above-mentioned origin return state based on the outputs of the discrimination sensors 32A, 32B, 32C and 32D. A deviation amount data storage means 48, a deviation amount selection means 49, and a deviation amount transfer means 50 are provided.

The storage means 48 stores each identification sensor 32.
In association with A, 32B, 32C, 32D, store a table that defines the deviation amount (0, n1, n2, n3) corresponding to the distance from the reference point Q0 corresponding to the original origin to each reference point. There is. The deviation amount selection means 49, when the home-return state is reached, the identification sensors 32A, 32B, 32.
Based on the outputs of C and 32D, the deviation amount corresponding to the corresponding identification sensor is selected and read from the storage means 48. Then, the deviation amount transfer means 50 transfers the selected deviation amount to the position counter 41.

FIG. 8 is a flow chart showing the origin adjusting method by the apparatus shown in FIG. In this flowchart, the drive of the motor 35 is started (step S12) when the determination as to whether or not the home-return control should be performed (step S11) is YES (step S12).
It is determined whether any one of Q0, Q1, Q2 and Q3 has been reached (step S13). When any one of the reference points is set, the motor 35 is continuously driven (step S1).
4) It is determined whether or not there is a zero signal from the encoder 36 (step S15). When there is the zero signal, the discrimination sensor at the position of the reference point examined in step S13 is discriminated (step S16), and the deviation amount corresponding to the discriminated discrimination sensor is read from the storage means, This is transferred to the position counter 41 (step S17). This deviation value is given to the position counter 41 as a reset value, and the origin return control ends.

If the determination in step S11 is NO, normal position control is performed (step S1).
8).

According to this embodiment, when the return-to-origin control is performed, the movable portion 33 on the motor shaft begins to move in the return-to-origin direction (arrow in FIG. 6) and then reaches the closest reference point in this direction. This is determined. For example, when the movable portion 33 is at the position shown by the solid line in FIG.
This is discriminated when reaching the reference point Q2 close to this point, and the point is moved to the position (shown by a chain double-dashed line) where the zero signal is output from the encoder 36 near the reference point Q2. Then, at this position, the deviation amount corresponding to the identification sensor 32C is given to the position counter 41, and the origin return operation is completed.

Therefore, when the position of the movable portion 33 at the time of starting the origin return is far from the reference point Q0 corresponding to the original origin, the moving distance until the completion of the origin return operation is compared with the case of moving to the original origin position. Significantly shortens the home return operation time. Moreover, since the deviation amount from the reference point Q0 corresponding to the original origin is given to the position counter 41, the position obtained by the output of the position counter 41 in the subsequent position control is the position based on the original origin position. And the origin adjustment function is achieved.

Although the robot axis is schematically shown in FIG. 6 in the third embodiment, the robot axis may be a translation axis or a rotary joint axis.

[0046]

According to the origin adjusting method of claim 1 and the origin adjusting device of claim 2 for carrying out the method, a signal indicating a rotation reference position near a predetermined reference point within the operating range of the robot axis. When the home position return operation is performed to the position where the error occurs, the measuring means for measuring the output of the encoder is provided with a predetermined deviation amount. Can be properly performed at the stage of returning to the origin. Therefore, when the origin shift occurs due to the displacement of the robot axis, or when a coordinate system in which the origin is intentionally shifted is assumed, the position control after the origin adjustment complicates the calculation process. It can be done properly while not doing so.

According to the origin adjusting method of the third aspect and the origin adjusting apparatus of the fourth aspect for carrying out the method, a plurality of reference points are set within the robot axis working range, and the origin return is performed among these. The home-return operation is performed near the reference point near the position after the start, and here the deviation amount according to the reference point is
By being given to the measuring means for measuring the output of the encoder, the origin adjustment can be achieved without returning to the original origin position, and the time required for the origin return can be greatly shortened.

[Brief description of drawings]

FIG. 1 is a schematic side view of a robot according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of an origin adjustment device.

FIG. 3 is a flowchart showing an origin adjustment method.

4A, 4B, and 4C are explanatory views of the first embodiment.

FIG. 5 is a schematic plan view of a robot according to a second embodiment.

FIG. 6 is an explanatory diagram showing a third embodiment.

FIG. 7 is a block diagram showing a configuration of an origin adjusting device according to a third embodiment.

FIG. 8 is a flowchart showing an origin adjusting method according to a third embodiment.

[Explanation of symbols]

 5,15 Motor 6,16 Encoder 11,41 Position counter 12,42 Control means 15,45 Reference point determination means 16,46 Home return determination means 18,48 Storage means 19,50 Deviation amount transfer means

Claims (4)

[Claims] 1. A robot axis composed of a rotary joint axis or a translation axis, drive means for driving the robot axis, a signal for detecting a drive amount of the drive means, and a rotation reference position for each rotation of the drive means. An encoder that outputs the rotation reference position signal shown, and measurement means that performs position detection based on the measurement of the output of the encoder are provided, and a reference point for setting the origin at a predetermined position within the working range of the robot axis is set. In the industrial robot described above, the robot axis is operated to the reference point side by the driving means, and the origin return operation is performed to operate the robot axis to a position near the reference point where the rotation reference position signal is generated. After that, the origin adjustment method for the industrial robot is characterized in that a predetermined deviation amount is given to the measuring means as a reset value at the end of the origin return operation. 2. A robot axis composed of a rotary joint axis or a translation axis, drive means for driving the robot axis, a signal for detecting a drive amount of the drive means, and a rotation reference position for each rotation of the drive means. An encoder that outputs the rotation reference position signal shown, and measurement means that performs position detection based on the measurement of the output of the encoder are provided, and a reference point for setting the origin at a predetermined position within the working range of the robot axis is set. In the industrial robot described above, the reference axis and the rotation reference position signal are determined while operating the robot axis by the drive means in response to the origin return command signal, and the rotation is performed in the vicinity of the reference point. The control means for performing the origin return operation of the robot axis to the position where the reference position signal is generated and the deviation amount corresponding to the origin shift amount according to the origin shift factor are described. And a deviation amount transfer means for giving the deviation amount read from the storage means as a reset value to the measuring means when the robot axis origin return operation is performed by the control means. Origin adjustment device for industrial robots. 3. A robot axis composed of a rotary joint axis or a translation axis, drive means for driving the robot axis, a signal for detecting a drive amount of the drive means, and a rotation reference position for each rotation of the drive means. An encoder that outputs the rotation reference position signal shown, and measurement means that performs position detection based on the measurement of the output of the encoder are provided, and a reference point for setting the origin at a predetermined position within the working range of the robot axis is set. In the industrial robot, a plurality of reference points are set in advance in the operation range of the robot axis at predetermined intervals, and the robot axis is operated in a predetermined direction by the driving means, and a reference point close to the operation start point is set. After the origin return operation that operates the robot axis is performed until the position where the rotation reference position signal is generated near the point, the measurement unit is caused to deviate by the amount of deviation corresponding to the reference point. The method of adjusting the origin of the industrial robot is characterized in that is given as a reset value at the end of the origin return operation. 4. A robot axis composed of a rotary joint axis or a translation axis, drive means for driving the robot axis, a signal for detecting a drive amount of the drive means, and a rotation reference position for each rotation of the drive means. An encoder that outputs the rotation reference position signal shown, and measurement means that performs position detection based on the measurement of the output of the encoder are provided, and a reference point for setting the origin at a predetermined position within the working range of the robot axis is set. In the industrial robots that are used, a plurality of reference point sensors that detect a plurality of reference points with a predetermined interval within the operation range of the robot axis, an identification means that identifies each reference point sensor, and a home return command signal In response, the signal from the reference point sensor and the encoder is read while driving the driving means, and the vicinity of any one of the plurality of reference points is read. The control means for returning the origin of the robot axis to the position where the rotation reference position signal is generated, the storage means for storing the deviation amount from the origin equivalent position for each reference point, and the origin of the robot axis by the control means. And a deviation amount transfer means for reading out the deviation amount of the corresponding reference point from the storage means based on the identification by the identification means when the returning operation is performed and giving the deviation amount to the measurement means as a reset value. Origin adjustment device for industrial robots.