JP2008083758A - Controller and movable range judgment method for machinery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily prevent a movable body from colliding with a movable end due to the mistake of an operation program without imposing any burden on an operator in machinery for moving the movable body back and forth on a predetermined path. <P>SOLUTION: The controller 15 for the machinery includes: a motor 12 for moving a movable object; a position detector 13; a driver 14; and a controller 15 for feeding a driving command to the driver 14; and an input/output device 18. This controller 15 is provided with a movable range setting part 26 for transmitting a positioning command to the driver 14, for acquiring a movable edge pulse count value when the movable object reaches the movable end and a pulse count value when an origin pulse is detected, for calculating the movable range of the movable body from a machinery origin and a movable edge pulse count value, and for performing a movable range setting operation for storing the calculated movable range as movable range information into a non-volatile memory 22. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a controller of a mechanical device and a movable range determination method that perform positioning while determining a movable range of a movable body that reciprocates on a predetermined path.

Conventionally, in a mechanical device that reciprocates a movable body on a predetermined path, mechanical position detection by sensors and limit switches is used to prevent the movable body from moving beyond the movable range due to an error in the operation program. And a soft position detection method in which the stroke end position is stored in the memory in advance using the stored stroke limit method as the movable range, and the stored data and the current position information from the encoder are compared during operation. (For example, refer to Patent Document 1).
JP 59-16008 A (FIG. 1)

However, the conventional methods using various sensors and limit switches have the problems that the apparatus becomes complicated due to an increase in wiring and control inputs, the necessity of installation space, and the cost increase.
Further, the stored stroke limit method has a problem that it takes time and effort to reset it when the origin position is adjusted.
The present invention has been made in view of such problems, and in a mechanical device that reciprocates a movable body on a predetermined path, it is simple and low-cost and does not impose a burden on an operator. It is an object of the present invention to provide a controller of a mechanical device and a movable range determination method that can prevent a movable body from colliding with a movable end due to a mistake or the like.

In order to solve the above problem, the present invention is configured as follows.
The invention according to claim 1 is a movable body that reciprocates on a predetermined path, a motor that moves the movable body, a position detector that is attached to the motor and generates an origin pulse at a predetermined position on the path; A driver for driving the motor; a controller for sending a drive command to the driver; and a controller for a mechanical device including an input / output device that communicates with the controller and performs status acquisition and function execution instructions. A positioning command is sent, and the movable end pulse count value when the movable body reaches the movable ends on both sides of the predetermined path and the pulse count value when the origin pulse is detected are obtained, and the pulse count value when the origin pulse is detected is obtained. Calculate the movable range of the movable body from the mechanical origin obtained by adding the offset amount of the origin and the movable end pulse count value, the movable range, It is characterized in that a movable range setting unit which performs movable range setting operation is stored in the nonvolatile memory the serial offset amount as the movable range information.
The invention according to claim 2 is the controller of the machine device according to claim 1, further comprising: a program storage unit for storing the motion program; and a program execution unit for reading and executing the program line by line from the program storage unit. The program execution unit determines whether or not the movable body exceeds the movable range based on the movable range information stored in the nonvolatile memory at the time of positioning the movable body, and exceeds the movable range. Only when there is not, the positioning command is executed.
According to a third aspect of the present invention, in the controller of the mechanical device according to the first aspect, when the program execution unit changes the offset amount of the origin, the movable range information stored in the nonvolatile memory and The movable range is recalculated from the offset amount, and whether or not the movable body exceeds the movable range is determined based on the recalculated movable range.
According to a fourth aspect of the present invention, in the controller of the mechanical device according to the first aspect, the movable range setting operation is executed by an origin return command when the movable range setting operation has never been performed. It is characterized by this.

According to a fifth aspect of the present invention, there is provided a movable body that reciprocates on a predetermined path, a motor that moves the movable body, and a position detection that is attached to the motor and generates an origin pulse at a predetermined position on the path. , A motor that drives the motor, a controller that sends a drive command to the driver, and a movable range determination method for a mechanical device that communicates with the controller and obtains status, performs function execution instructions, and the like , A positioning command is sent to the driver, and the movable end pulse count value when the movable body reaches the movable ends on both sides of the predetermined path and the pulse count value at the time of detecting the origin pulse are obtained. The movable range of the movable body is calculated from the mechanical origin obtained by adding the offset amount of the origin to the pulse count value and the movable end pulse count value, Dynamic range, characterized in that to perform the movable range setting operation is stored in the nonvolatile memory the offset amount as the movable range information.
Further, the invention according to claim 6 is the movable range determination method of the mechanical device according to claim 5, wherein the movable unit is based on the movable range information stored in the nonvolatile memory at the time of positioning the movable body. It is determined whether or not the body exceeds the movable range, and the positioning command is executed only when the body does not exceed the movable range.
According to a seventh aspect of the present invention, in the movable range determination method for a mechanical device according to the fifth aspect, when the offset amount of the origin is changed, the movable range information and the offset amount stored in the nonvolatile memory are changed. Then, the movable range is recalculated, and based on the recalculated movable range, it is determined whether or not the movable body exceeds the movable range.
The invention according to claim 8 is the method for determining the movable range of the mechanical device according to claim 5, wherein the movable range setting operation is an origin return command when the movable range setting operation has never been performed. It is characterized by being executed in step (b).

According to the inventions described in claims 1, 2, 5, and 6, the movable end pulse count value when the movable body reaches the movable ends on both sides of the predetermined path and the pulse count value at the time of detecting the origin pulse are acquired, The movable range of the movable body is calculated from the mechanical origin obtained by adding the offset amount of the origin to the pulse count value at the time of origin pulse detection and the movable end pulse count value, and the non-volatile memory uses the movable range and offset amount as the movable range information. When the movable body positioning command is issued, it is determined whether or not the movable body exceeds the movable range based on the movable range information stored in the nonvolatile memory, and the movable range is not exceeded. Since the positioning command is executed only in such a case, it is possible to prevent the movable body from colliding with the movable end due to a mistake in the operation program or the like at a simple and low cost.
According to the third and seventh aspects of the invention, when the offset amount of the origin is changed, the movable range is recalculated from the movable range information and the offset amount stored in the nonvolatile memory, and the recalculated movable range is obtained. Based on this, since it is determined whether or not the movable body exceeds the movable range, even when the mechanical origin is changed, the movable body can be easily prevented from colliding with the movable end.
According to the fourth and eighth aspects of the invention, since the movable range setting operation is executed by the origin return command when the movable range setting operation has not been performed, the movable range setting operation can be performed without imposing a burden on the operator. The body can be prevented from colliding with the movable end.

  Hereinafter, specific examples of the method of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram illustrating a configuration example of a mechanical device controlled by a controller of the present invention.
A laser processing apparatus using a galvanometer is shown as an example of a mechanical apparatus that reciprocates a movable body on a predetermined path. Laser processing technology using a galvanometer is used for processing circuit boards with high-density wiring, and a laser beam reflected by a galvanometer mirror (movable body) attached to the galvanometer is applied to an irradiation surface of a workpiece. It is processed by irradiation or dissolution or evaporation.
Here, the galvanometer is for rotating a galvanometer mirror, and corresponds to a motor for operating a movable shaft with a ball screw or the like, and the motor described in the claims includes a galvanometer.
In the figure, 11 is a galvanometer mirror, and 12 is a galvanometer that rotates the galvanometer mirror. The galvanometer 12 is connected to an encoder 13 which is a position detector and a driver 14 for operating the galvanometer mirror 11. The galvanometer 12 is rotated according to the drive current from the driver 14, and the rotation angle is the encoder 13. And supplied to the driver 14. A controller 15 gives an irradiation position command to the driver 14, and the driver 14 outputs a drive current to the galvanometer 12 based on the irradiation position command and position information from the encoder 13. The controller 15 includes a parameter / position storage area 22 that is a nonvolatile memory and a movable range setting unit 26 that performs a movable range setting operation. A laser oscillator 16 outputs a laser beam to the galvanometer mirror 12. Reference numeral 18 denotes an input / output device such as a personal computer, which communicates with the controller 15 and obtains the status of the machine device and issues a function execution instruction.
FIG. 2 is a diagram for explaining the galvanometer 12 and the galvanometer mirror 11, and is a view of the galvanometer 12 as viewed from the position where the galvanometer mirror 11 is attached. In the figure, 17 is a stopper for limiting the rotation angle of the galvanometer 12. In the laser processing technology using a galvanometer, generally, high-speed and high-precision irradiation positioning is performed with a drive angle of about ± 20 °. In this example, it is assumed that the galvanometer 12 rotates clockwise.

FIG. 3 is a block diagram showing the configuration of the controller 15 of the present invention. In the figure, 21 is a central processing unit that supervises each function of the controller, 22 is a parameter storage area, which is a non-volatile memory that can retain stored contents even when the power is turned off. Controller parameters are stored in this area. The In the present invention, the fact that this area is a non-volatile memory, in addition to the parameters, the movable range from the mechanical origin to the movable end in both directions by adding the offset amount to the pulse count value at the time of origin pulse detection, and the origin It is assumed that position offset data is stored. A non-volatile memory 23 is a program storage area for storing a motion program describing a movement command of the movable body. Reference numeral 24 denotes a battery for these nonvolatile memories.
Reference numeral 25 denotes an origin return processing unit that performs origin return processing, 26 denotes a movable range setting unit that performs positioning to the movable end and performs a movable range setting operation based on the movable end pulse count value, and 27 reads and executes a program from the program storage area. It is a program execution part.
28 is a command unit for the driver 14, and 29 is a monitor unit that acquires status such as position information of the galvanometer 12 from the driver 14. A communication unit 30 exchanges data with the input / output device 18.
Reference numeral 31 denotes a position storage area composed of a RAM (Random Access Memory), which temporarily stores the movable end pulse count value when the movable end is reached and the pulse count value when the origin pulse is detected. These data are necessary to calculate the movable range.

FIG. 4 is an operation explanatory diagram during the movable range setting operation. FIG. 4 shows the galvanometer 12 as viewed from the attachment position side of the galvanometer mirror 11 (upper semicircle), and the galvanometer mirror 11 is not shown in the figure for explanation. In the figure, reference numeral 41 denotes a swivel pin, which stops the rotation shaft at the position of the stopper 17 so that the rotation shaft of the carbanometer 12 does not rotate more than the drive angle. In the following description, “contacting the movable end” means that the rotation retaining pin 41 contacts the stopper 17, and the blocking member refers to the stopper 17.
ZP is an origin position, and is usually an origin pulse detection position for detecting an origin pulse. When the rotation axis reaches this position, the encoder 13 gives an origin pulse to the drive device 14. Note that an offset amount is added to the origin indicated by the origin pulse detection position, and this can be used as the machine origin. In this case, when returning to the origin, the position obtained by adding the offset value to the pulse count value when the origin pulse is detected is used as the machine origin. If the offset value is 0, positioning is performed at the origin pulse detection position. The operation by the motion program operates based on the machine origin positioned by the origin return operation.

The movable range setting operation will be described with reference to FIGS.
First, the operator uses the input / output device 18 to instruct the return of the origin of the movable body (rotating pin 41). When a return to origin is commanded by the operator, the movable range setting unit 26 is activated, reads the movable range information from the parameter storage area 22, and sets a movable range set flag indicating whether or not the movable range setting operation has been performed once. Check and if it is not set, move range is set. If it has been set, the process returns to the origin return processing unit 25 to perform a normal origin search.
First, the movable range setting unit 26 positions the movable body to the left or right. In the example of FIG. 4A, the positioning is initially performed on the right side, but may be started from the left side. A positioning command is generated and commanded to the driver 14 via the command unit 28. For the amount of movement used for positioning, for example, since the total number of pulses of a predetermined path can be estimated in advance, a value larger than the number of pulses is used.
The driver 14 outputs a drive current to the galvanometer 12 based on the positioning command and the position information from the encoder 13. As shown in FIG. 4A, the rotational axis of the galvanometer 12 starts positioning at the right movable end. The movable range setting unit 26 repeatedly obtains the status of the galvanometer 12 from the driver 14 via the monitor unit 29 during positioning, and confirms that the rotation axis of the galvanometer 12 has not reached the movable end (the locking pin in FIG. 4). 41 is not in contact with the stopper 17).
As the determination means, there are a method of using a fluctuation amount of the current position and a method of using a deviation between the command position and the current position, and any of them may be adopted.
Here, the status includes the current position of the galvanometer 12 and whether or not the origin pulse is detected, and if it is detected, the position information is also targeted.
At the same time as determining whether or not the movable end has been reached, the detection of the origin pulse is also checked. When the origin pulse is detected, the pulse count value of the detected position is obtained from the driver 14 via the monitor unit 29 and stored in the position storage area 31. Store. In the example of FIG. 4, since the origin is on the left side of the movement start position, the origin pulse is not detected and reaches the movable end.

When it is determined that the rotation axis of the galvanometer 12 has reached the movable end, the movement is stopped. After the stop, the movable range setting unit 26 acquires the pulse count value at the movable end from the driver 14 via the monitor unit 29 and stores it in the position storage area 31. Here, the acquisition position is X (FIG. 4B).
Next, the movable range setting unit 26 performs positioning in the reverse direction (left direction). The amount of movement is set to a value larger than the total number of pulses in the predetermined path. The movable range setting unit 26 repeatedly acquires the status of the galvanometer 12 from the driver 14 during execution of positioning. In the case of FIG. 4, the origin pulse is detected before reaching the movable end. When the origin pulse is detected, the movable range setting unit 26 acquires the pulse count value of the detected position from the driver 14 via the monitor unit 29 and stores it in the position storage area 31. Here, the acquisition position is Y (FIG. 4C). The movable range setting unit 26 continuously acquires the status of the galvanometer 12 from the driver 14, and stops moving when determining that the rotation axis of the galvanometer 12 has reached the movable end. After the stop, the movable range setting unit 26 acquires the pulse count value at the movable end from the driver 14 via the monitor unit 29 and stores it in the position storage area 31. Here, the acquisition position is Z (FIG. 4 (d)).
Next, the movable range setting unit 26 obtains the pulse count value of the origin pulse detection position from the position storage area 31, and when the offset amount is 0, it is set as the machine origin, and when the offset is other than 0, the offset amount is obtained. A positioning command is created using the added value as the machine origin, and commanded to the driver 14 via the command unit 28. Here, the position of the machine origin is YA. After the positioning to the machine origin is completed, the position is set as the origin, and the origin return is completed (Fig. 4 (c)).
Finally, the movable range setting unit 26 calculates a movable range in both the left and right directions from the origin position. From the movable end pulse count values X and Z and the machine origin position YA, the movable range on the right side from the origin position is given by X-YA and the movable range on the left side is given by YA-Z. The movable range setting unit 26 stores this movable range in the parameter storage area 22. Since this movable range is stored in the nonvolatile memory, it is retained even when the power is turned off.
Therefore, when the power is turned on after the next time, it is not necessary to acquire the pulse count values of both movable ends, and only the origin search is performed. The origin search means obtains the status of the galvanometer while moving as described above, determines whether or not an origin pulse has been detected, and positions it at the machine origin when it is detected. If one of the movable ends is touched during the origin search process, the distance to the machine origin can be calculated from the movable range information. Also good.

Next, details of the movable range setting unit 26 will be described.
When the origin return is instructed, the movable range setting unit 26 is activated.
FIG. 5 is a flowchart showing a processing procedure of the movable range setting unit 26.
FIG. 5A is a main process, and FIG. 5B is a subroutine of origin pulse / movable end check.
First, the movable range information stored in the parameter area 22 in the main step S1 is read. Next, in step S2, it is checked whether the movable range has been set by the movable range set flag. If it has been set, the process moves to the origin return processing unit 25 to perform origin search processing. If not set, the process proceeds to step S3, where a positioning command is generated and issued. For the movement amount used for positioning, for example, a value larger than the total number of pulses of a predetermined path is used.
Next, in step S4, the origin pulse and movable end check subroutine shown in FIG. 5B is called.
In the subroutine, the status is acquired in step S31, and it is checked whether an origin pulse is detected in step S32. If detected, the pulse count value at the origin pulse detection position is acquired in step S33 and stored in the position storage area 31. In step S34, it is checked whether or not the movable end has been touched. If so, the process returns to the main routine. If not, the process proceeds to step S31.
Thus, in this subroutine, when the origin pulse is detected, the pulse count value at the origin pulse detection position is acquired and stored, and when the movable end is touched, the subroutine returns.
In step S5, since it is in contact with the movable end, a stop command is generated and issued. The status is acquired in step S6, and the stop is checked in step S7. If the stop can be confirmed, the process proceeds to step S8 where the movable end pulse count value is acquired and stored in the position storage area 31.
In step S9, a position command in the reverse direction is generated and issued. In step S10, the origin pulse / movable end check subroutine is called again, and when the origin pulse is detected, the pulse count value at the origin position is acquired and stored.
In step S11, since the movable end is in contact, a stop command is issued in steps S11 to S13 to confirm the stop.
In step S 14, the movable end pulse count value is acquired and stored in the position storage area 31.
In step S15, a position command to the machine origin is generated and issued. The completion of positioning is confirmed in steps S16 and S17, and the origin is set in step S18. In step S 19, the movable range is calculated, and the result and the movable range set flag are stored in the parameter storage area 22.

Next, a method for determining the movable range when the positioning command is executed will be described.
The operator instructs the controller 15 to execute the motion program from the input / output device 18 after the return to origin is completed. The central processing unit 21 instructs the program execution unit 27 to execute the program. The program execution unit 27 determines whether the command is within the movable range when executing the program line by line.
FIG. 6 is a flowchart showing the processing procedure of the program execution unit 27.
First, the movable range information is read from the parameter storage area 22 in step S41. Next, in step S42, one line of the motion program is read from the program storage area 23, and execution is started. In step S43, the command is analyzed, and a positioning command value is calculated from the target position. In step S44, it is checked whether the target position is included in the movable range from the calculation result and the movable range information. If the target position does not exceed the movable range as a result of the check, the process proceeds to step S45 to generate and issue a position command. If the execution of all the rows is completed in step S46, the process ends. If the target position exceeds the movable range in step S44, the position command is not generated and execution of the program is stopped in step S47. At this time, an alarm may be sent to the input / output device 18 via the communication unit 30 as in step S48.

Next, the operation for changing the offset amount of the origin will be described.
The operator uses the input / output device 18 when changing the machine origin to a position obtained by adding an offset amount to the origin pulse detection position instead of the origin pulse detection position, or when changing the offset amount already set. Then, the new offset amount is set in the controller 15. The central processing unit 21 stores the new offset amount in the parameter storage area 22. In this state, when the origin return is executed, the origin return processing unit 25 positions at a position obtained by adding a new offset amount to the origin pulse detection position. In this state, when the operator instructs the controller 15 to execute the motion program, the program execution unit 27 reads the movable range information from the parameter storage area 22 and recalculates the movable range using the new offset amount. . Next, the motion program is read from the program storage area 26, and execution is started. The movable range determination during execution is as described in the explanation of FIG.

  As described above, according to the present invention, by obtaining the pulse count value at the movable end of the predetermined path and the pulse count value at the origin position, the movable range in both the left and right directions from the origin position is calculated, and positioning is performed based on the movable range. Since the command is determined and the positioning command is executed only when the movable range is not exceeded, collision with the movable end can be prevented. In addition, since the movable range information in both the left and right directions is stored in the non-volatile memory, it is not necessary to measure the pulse count value of both movable ends at the time of origin return for the second and subsequent times, and automatically starts from the origin search. To do. Even when the machine origin is changed from the first return to origin, the movable range at the machine origin can be calculated from the fluctuation and the movable range in both the left and right directions. The movable range can be determined without measuring the value. Moreover, various sensors and limit switches are not required, and it is possible to prevent the movable body from colliding with the movable end due to a mistake in the operation program or the like at low cost.

  The present invention can be applied not only to a laser processing apparatus using a galvanometer but also to a determination of a movable range of a device that reciprocates a movable body on a predetermined path, for example, a mechanical device that moves a work table by connecting a ball screw and a motor.

The figure which shows the structural example of the machine apparatus which the controller of this invention controls Diagram explaining galvanometer and galvanometer mirror The block diagram which shows the structure of the controller of this invention Operation explanatory diagram during movable range setting operation The flowchart which shows the process sequence of a movable range setting part. Flow chart showing processing procedure of program execution unit

Explanation of symbols

11 Galvanometer mirror 12 Galvanometer 13 Encoder 14 Driver 15 Controller 16 Laser oscillator 17 Stopper 18 Input / output device 21 Central processing section 22 Parameter storage area 23 Program storage area 24 Battery 25 Origin return processing section 26 Movable range setting section 27 Program execution section 28 Command Unit 29 monitor unit 30 communication unit 31 position storage area 41 rotation pin

Claims (8)

A movable body that reciprocates on a predetermined path;
A motor for moving the movable body;
A position detector attached to the motor and generating an origin pulse at a predetermined position on the path;
A driver for driving the motor;
A controller for sending a drive command to the driver;
In the controller of the machine device consisting of an input / output device that communicates with the controller and performs status acquisition and function execution instructions,
A positioning command is sent to the driver, and the movable end pulse count value when the movable body reaches the movable ends on both sides of the predetermined path and the pulse count value when the origin pulse is detected are obtained, and the pulse when the origin pulse is detected The movable range of the movable body is calculated from the machine origin obtained by adding the offset amount of the origin to the count value and the movable end pulse count value, and the movable range and the offset amount are stored in the nonvolatile memory as movable range information. A controller for a machine apparatus, comprising a movable range setting unit that performs a movable range setting operation. A program storage unit for storing motion programs;
A program execution unit that reads and executes the program line by line from the program storage unit;
When the program execution unit determines whether or not the movable body exceeds the movable range based on the movable range information stored in the nonvolatile memory at the time of positioning the movable body, and does not exceed the movable range The machine controller according to claim 1, wherein only the positioning command is executed.   The program execution unit, when changing the offset amount of the origin, recalculates the movable range from the movable range information and the offset amount stored in the nonvolatile memory, based on the recalculated movable range, 2. The controller of a mechanical device according to claim 1, wherein it is determined whether or not the movable body exceeds a movable range.   2. The controller of a machine apparatus according to claim 1, wherein the movable range setting operation is executed by an origin return command when the movable range setting operation has never been performed. A movable body that reciprocates on a predetermined path;
A motor for moving the movable body;
A position detector attached to the motor and generating an origin pulse at a predetermined position on the path;
A driver for driving the motor;
A controller for sending a drive command to the driver;
In the method of determining the movable range of a mechanical device composed of an input / output device that communicates with the controller and obtains status, performs function execution instructions, etc.
A positioning command is sent to the driver, and the movable end pulse count value when the movable body reaches the movable ends on both sides of the predetermined path and the pulse count value when the origin pulse is detected are obtained, and the pulse when the origin pulse is detected The movable range of the movable body is calculated from the machine origin obtained by adding the offset amount of the origin to the count value and the movable end pulse count value, and the movable range and the offset amount are stored in the nonvolatile memory as movable range information. A movable range determination method for a mechanical device, characterized in that a movable range setting operation is performed.   At the time of positioning the movable body, it is determined whether the movable body exceeds the movable range based on the movable range information stored in the nonvolatile memory, and the positioning command is executed only when the movable range is not exceeded. The method of determining a movable range of a mechanical device according to claim 5.   When the offset amount of the origin is changed, the movable range is recalculated from the movable range information stored in the nonvolatile memory and the offset amount, and the movable body is moved within the movable range based on the recalculated movable range. 6. The method of determining a movable range of a mechanical device according to claim 5, wherein it is determined whether or not the maximum value exceeds.   6. The method of determining a movable range of a mechanical device according to claim 5, wherein the movable range setting operation is executed by an origin return command when the movable range setting operation has never been performed.

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