JP3198010B2 - Control method and control device for machine tool - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control method and a control device for a machine tool, and more particularly to a method for simultaneously executing a plurality of blocks of a control program and relating each control axis of a machine tool having a plurality of control axes. TECHNICAL FIELD The present invention relates to a control method for performing control so as to operate the control device and a control device for executing the control method.

[0002]

2. Description of the Related Art A machine tool having a plurality of control axes (movable parts independently controllable) controlled by a control program, such as a numerical controller, executes a plurality of blocks of the control program at the same time. Control is performed so that each control axis operates in relation to each other.

In this case, for example, control is performed by a control program of an independent system for each control axis to adjust the timing between the systems. For example, as disclosed in JP-A-1-303502, A method in which a start wait command is input to each block of a program to be executed at the same time, and the earlier execution of the preceding block is terminated earlier, and the later execution is synchronized with the execution start timing of each block. The execution start timing was adjusted with a waiting time.

[0004]

However, in the above-described machine tool, the timing of ending each operation by a plurality of control axes (the completion of a predetermined machining operation, the completion of movement to a target position, etc.) is accurately synchronized. However, there is a problem that the conventional control method cannot perform such control, which results in unnecessary waiting time and delicate timing adjustment between control programs of a plurality of systems. there were.

The present invention has been made in view of such a problem, and reduces the waiting time when the control axes of a machine tool having a plurality of control axes are operated in relation to each other to reduce the processing time. And to enable accurate synchronization of the end timing of each operation by a plurality of control axes.

[0006]

SUMMARY OF THE INVENTION According to the present invention, there is provided a machine tool for simultaneously executing a plurality of blocks of a control program and controlling each control axis of a machine tool having a plurality of control axes to operate in relation to each other. In order to achieve the above object, in the control method of (1), the following steps (a) to (d) are executed to synchronize the execution end timings of a plurality of blocks of the control program to be executed simultaneously. And

(A) converting a plurality of blocks to be executed at least simultaneously of the control program into an executable form;
(b) calculating the execution time of each block converted into the execution format, and (c) among the plurality of blocks to be executed simultaneously, the execution start timing is continuous in time from the start of the control program. Identifying a predetermined block,

(D) From the execution start timing and execution time of the specified block and the execution time of the block whose execution start timing is not determined among a plurality of blocks executed at the same time, the execution end timing of the plurality of blocks is determined. Calculating and determining the execution start timing of the block whose execution start timing has not been determined so as to be synchronized;

[0009] The control program may comprise a plurality of systems of control programs, and the plurality of blocks to be executed simultaneously belong to different systems of control programs. In this case, it is preferable that each block belonging to each control program of the plurality of systems to be executed at the same time is provided with an end wait command indicating that the execution end timing is synchronized.

[0010] One or more blocks before the block having the end wait instruction and having an execution start timing not determined in advance may be executed continuously with the block having the end wait instruction. In this case, a continuous execution command may be input to a block that is to be executed continuously with the block having the end waiting command. Alternatively, information for designating the number of blocks to be executed continuously with the block having the command may be inserted in the end wait command.

[0011] The present invention also provides a machine tool control device for simultaneously executing a plurality of blocks of a control program and controlling each control axis of a machine tool having a plurality of control axes to operate in relation to each other. In order to achieve the above object, the present invention also provides an apparatus in which the following means (1) to (4) are provided to synchronize the execution end timings of a plurality of blocks of the control program which are simultaneously executed.

(1) a program conversion means for converting a plurality of blocks of the control program, which are executed at least simultaneously, into an executable form; (2) an execution time for calculating an execution time of each block converted into an executable form by the means; Calculating means, (3) a block specifying means for specifying a block which is temporally continuous from the start of the control program and whose execution start timing is predetermined, among the plurality of blocks to be simultaneously executed,

(4) From the execution start timing and execution time of the block specified by the means and the execution time of the block whose execution start timing is not determined among the plurality of blocks to be executed simultaneously, the plurality of blocks are determined. Execution end synchronization means for calculating and determining the execution start timing of the block whose execution start timing has not been determined, so that the execution end timings of the blocks are synchronized.

[0014]

According to the machine tool control method and the control device of the present invention, all of the control program for controlling the control axes of the machine tool having a plurality of control axes to operate in association with each other, or A plurality of blocks to be executed at least simultaneously are converted into an execution format in advance, and the execution time of each block converted into the execution format is calculated.

[0015] Of a plurality of blocks to be executed at the same time, the execution start timing and execution time of the block which is temporally continuous from the start of the control program and whose execution start timing is predetermined, and the execution start timing are determined. From the execution time of the block that has not been executed, the execution end timing of the plurality of blocks is synchronized.
By calculating and determining the execution start timing of the block whose execution start timing has not been determined, the execution end timings of a plurality of blocks that are simultaneously executed by the control program are synchronized.

Therefore, it is possible to reduce the waiting time for the operations related to each other by the plurality of control axes of the machine tool to shorten the machining time, and to accurately synchronize the end timings of the operations. Even if the plurality of blocks to be executed simultaneously belong to different control programs, the execution end timing of each block can be synchronized.

In this case, if each block to be executed simultaneously in the control program of each system is provided with an end waiting command indicating that the execution end timing is synchronized, the execution end is executed when each of the above processes is performed. Blocks that need to be synchronized in timing are easily identified.

Further, among a plurality of blocks to be executed at the same time, a block whose execution start timing is not predetermined and one or more blocks earlier than the block are successively executed to execute a plurality of related operations by the same control axis. It can be performed continuously, and the operation end timing can be synchronized with the operation end timing of another control axis.

In this case, if a continuous execution command is inserted in the block to be continuously executed or information for designating the number of blocks to be continuously executed is entered in the end waiting command, the end waiting command is issued. It is possible to easily determine which block should be executed successively for blocks having the same.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a control device for implementing a method of controlling a machine tool according to the present invention. A broken line M indicates a drive unit side of a machine tool having a plurality of control axes.

This control device comprises a system control unit 1 having a CPU, an input switch 2 having a plurality of keys,
The display 3 includes an indicator 3 such as an RT or an LCD, and an input / output controller 4 for controlling input of various commands from the input switch 2 and display of various information on the display 3.

Further, a system control program memory (ROM) 5 and a system memory (RAM) 6 are provided. The system control unit (CPU) 1 is provided with a system control program stored in the system control program memory 5. Accordingly, various processes according to the present invention are executed using the system memory 6 as a working memory, and the control device is entirely controlled.

Further, according to the present invention, a control program storage unit (ROM or RAM) 7 for storing a control program for each axis of a machine tool to be controlled, and an execution program for storing a program converted into an execution format. A format program storage unit (RAM) 8, a program format conversion unit 9, an execution time calculation unit 10, an execution start timing fixed block identification unit 11, an execution end synchronization unit 12, a control program processing unit 13, and an operation control unit 14. ing.

The program format conversion unit 9 converts at least a plurality of blocks of the control program stored in the control program storage unit 7 to be executed at least simultaneously into an execution format, and stores the converted program in the execution format program storage unit 8. . The execution time calculation unit 10 calculates the execution time of each block of the program converted into the execution format stored in the execution format program storage unit 8.

Execution start timing decision block specifying unit 1
Reference numeral 1 designates a block which is temporally continuous from the start of the control program and whose execution start timing is predetermined, among the plurality of blocks to be executed simultaneously. Alternatively, even if a system of a program that is temporally continuous from the start is specified, a block whose execution start timing is predetermined can be specified.

The execution end synchronization unit 12 executes the execution start timing of the specified block and the execution time calculated by the execution time calculation unit 10 and executes the execution start timing of a plurality of blocks which are not executed at the same time. From the time, the execution start timings of the blocks whose execution start timings have not been determined are calculated and determined so that the execution end timings of the plurality of blocks are synchronized (matched). The processing of these units is performed by the CP of the system control unit 1.
Performed by U.

In this way, the control program of the execution format including the block whose execution start timing is determined is sequentially sent to the control program processing unit 13 for execution processing, and the operation control unit 14 controls the drive pulse at the execution start timing of each block. Are controlled to control the motor control drive units 21, 22,... Of each axis of the machine tool to drive the motors 23, 24,. Servo motors are preferably used for the motors 23, 24,. The operation control unit 14 further sends a control signal to a plurality of actuator control driving units 25 and the like to drive the actuators 26 and the like,
And the like are input via the sensor input unit 27 and the like.

As described above, by synchronizing the execution end timings of a plurality of blocks simultaneously executed by a plurality of control programs, a waiting time when the control axes of the machine tool are operated in relation to each other is reduced. As a result, the machining time can be reduced, and the end timing of each operation by the plurality of control axes can be accurately synchronized (matched).

In this embodiment, the process of converting each block of the control program into an executable format by the program format converting unit 9 may be performed by reading all the blocks of the control program in advance and converting them into an executable format by a compile method. The execution time and start condition of each block can be obtained.

The start condition is a condition for starting execution of the block. The start condition is a time starting from the beginning of the program or a designated point, or completion of operation, completion of the block, designation of a control axis in the middle of the block. Position, velocity,
This means conditions such as the time of detection of torque and the like, after a specified dwell time, and the like.

When a wait command is issued between two or more systems of a multi-system program so that the end of each block is completed at the same time, the blocks of all the systems simultaneously execute at the point where the end wait is instructed. In order to end the execution, the execution start condition of the block having the end waiting or the block before (or a plurality of blocks before) may be determined again.

In general, the end of the latest completed block is waited for the end of another earlier completed block. In this case, a method of shifting the start time so that the end of only the last one block is matched, and a method of moving a group of a plurality of blocks before the last one block and going back to a block which does not have a constraint due to other waiting before that one block. ,
There is a method of shifting the start time of each block.

A queuing command is issued between two or more systems of a multi-system program under specific conditions (position, time, block start, etc.) of a block of one system so that blocks of another system are simultaneously finished. Then, similarly to the above, the execution start condition of the block waiting for completion or the block before that (there may be a plurality of blocks) is determined again.

An error (alarm) is generated when the end wait command and other wait conditions cause inconsistency, and an error (alarm) is generated when other conditions are inconsistent. This can be provided for convenience when checking a program.

The start condition is reconfigured for blocks subsequent to the block in which the end wait instruction is issued, taking into account the changes that occur due to the end wait. After the above processing is completed, the execution data of all the blocks is stored in the execution format program storage unit 8 of FIG. 1, and the compilation processing ends. However, according to this compilation method,
Since the execution format program storage unit 8 needs a memory capacity for storing execution data of all blocks in advance, the cost increases.

Therefore, the control method of the present invention can be executed by adopting an interpreter system in which a control program is read in one block or a predetermined number of blocks before execution and converted into an execution format. . FIG.
FIG. 9 is a flowchart of a prefetch conversion process of a control program by an interpreter method in this embodiment.

When this processing is started, first, in step 1, the number M of prefetch blocks is set. This is to set the number of prefetch blocks of a system that is temporally continuous from the start of the control program and whose execution start timing of each block is predetermined, and does not add the number of prefetch blocks of other systems. Then, in step 2, one block of the control program is read, and in step 3, it is determined whether or not an end waiting command is issued. If it is an end waiting command, the flow advances to step 4 to execute a subroutine for end waiting instruction processing. The processing content will be described later.

If it is not an end waiting command, step 5
Then, the block is converted into an executable format, and in step 6, the result of the conversion is stored in the executable format program storage unit 8 (FIG. 1). Next, in step 7, it is determined whether or not the block is the last block. If so, the process proceeds to step 10, in which the conversion result of the remaining block stored in the executable program storage unit 8 is sent to the control program processing unit 13 to execute And
The process ends.

If it is not the last block, M
Judge whether the conversion result of the +1 block is stored,
If not, the flow returns to step 2 to read the next block of the control program, and repeat the above processing. When the conversion result of the (M + 1) th block is stored, the conversion result of the first stored block is stored in the control program processing unit 1.
Then, the process returns to step 2 after being sent to step 3.

In this way, for example, when M = 3, as shown in FIG. 4, the control program stored in the control program storage 7 is read from the first block one block at a time, In step 9, the data is converted into an executable format and sequentially stored in the executable format program storage unit 8.
When the conversion result of the fourth block, which is the block, is stored, the conversion result of the first stored block (the first block in the illustrated example) is sent to the control program processing unit 13 and executed.

Thereafter, each time one block is converted and stored in the execution format program storage section 8, the conversion results from the second block, the third block and the previously stored block are sequentially sent to the control program processing section 13 and executed. .

Next, the contents of the subroutine of the end wait command processing in step 4 in FIG. 2 will be described with reference to the flowchart in FIG. When this process is started, first, at step 11, N = 0 is set, and at step 12, an execution start timing determination system (a system which is temporally continuous from the start of the program and whose execution start timing of each block is predetermined) is set. Identify.

Then, in step 13 , the control program of the next block (a plurality of blocks to be executed at the same time) of the end wait command of all the systems is read. Here, step 1
The block of the system specified in 2 is specified as a block whose execution start timing is predetermined. Next, the read program of each block is converted into an executable form in step 14, and the program is executed in step 15.
Calculates the execution time of each converted block. Then, in step 16, it is determined whether or not the execution time of the execution start timing decision system (block) is the longest.

If the determination is YES, step 17
Calculates the execution start timing of the block of another system. That is, based on the execution start timing ta and the execution time TA of the block of the execution start timing determined system and the execution time TB of the block of the other system, the other blocks are synchronized so that the execution end timing of each block is synchronized (matched). Assuming that the execution start timing of the system block is tb, Equation 1
Is calculated.

[0045]

## EQU1 ## tb = ta + (TA-TB)

At step 18, an instruction of the execution start timing calculated and determined at step 17 is added to the execution format program of the block of the other system, and the processing of this subroutine is completed. Return to the processing of. If the execution time of the block of the execution start timing determined system is not the longest in the determination of step 16, N is incremented by 1 in step 19, and the block before the block N of the execution start timing determined system end wait command is determined in step 20. Read.

Then, in step 21, the data is converted into an execution format, and in step 22, the execution time of the block is calculated. In step 23, the calculated execution time is added to the execution time of the block of the execution start timing decision system, and the process returns to the determination in step 16. As a result, if the execution time of the execution start timing decision system (in this case, the execution time of the block waiting for completion and the immediately preceding block) is the longest, the process proceeds to step 17; otherwise, the process proceeds to step 19 again. In step 2, the N is further increased by
The processing of 0 to 23 is repeated.

Here, the calculation of the execution start timing of a block of another system will be described with reference to FIG. (A)
Shows an example when N = 0, and (b) shows an example when N = 1. Blocks indicated by diagonal lines in the figure are end waiting commands, and the blocks on the right side thereof are a plurality of blocks that are simultaneously executed to synchronize their execution end timings. ta, tb, TA, and TB are as follows. ta: execution start timing of the block of the execution start timing determined system, TA: the execution time of the block (for 1 + N blocks) tb: execution start timing of the block of the other system, TB: the execution time of the block

In order to calculate the execution start timing tb of the block of the other system by the calculation of the above equation 1, it is necessary to use TA
> TB, so if TA <TB,
As shown in FIG. 5B, N = 1, the execution start timing of the block one block before the end wait instruction of the execution start timing determination system is set to ta,
Let TA be the execution time of the block.

If TA> TB still does not hold, N
= 2, the execution start timing of the block two blocks before the end wait instruction of the execution start timing decision system is set to ta, and the execution time of the subsequent three blocks is set to TA. In this manner, N is increased until TA> TB. In this case, when the number M of prefetched blocks in the prefetching process of the interpreter system shown in FIG. 2 becomes N + 2> M, the execution start timing of the already executed block is requested later, and the execution start timing is determined. Can not be.

Next, a description will be given of an embodiment in which the present invention is applied to an NC lathe so as to synchronize the end of the parting-off with the parting-off tool with the completion of the advance of the separator for receiving the processed work.

FIG. 6 is a plan view of a main part of an NC lathe embodying the present invention, in which a spindle 31 is rotatably held by a headstock 30, and a chuck 31a is built in the tip of the spindle 31. Further, a guide bush device 36 having a guide bush 32 having a common axis L with the main shaft 31 in front thereof.
Is fixed.

Then, a round bar-shaped working material 34 is passed through the main shaft 31 and the guide bush 32, and the work piece (hereinafter referred to as "work") is formed from the guide bush 32.
The work material 34 is also rotated by the rotation of the main shaft 31 caused by the rotation of a motor (not shown) by projecting by 35 and fixing and holding the chuck. The spindle 31 holding the work material 34 moves together with the headstock 30 in a direction (along arrow A) along an axis L indicated by a dashed line.

On the other hand, a comb-shaped or turret-type tool rest (not shown) is provided around the guide bush 32, and various types of cutting tools (knives) are selected.
The workpiece 35 is processed by moving the workpiece 35 in a direction perpendicular to the axis L (the direction indicated by the arrow B). The workpiece 35 that has been processed is cut off from the processing material 34 by the advance of the cut-off tool 33.

At that time, the work collecting device 40 advances the work receiver 44 as a separator from the standby position HP shown by the solid line to the advance position FP immediately below the processing position shown by the virtual line, receives the work 35, and again receives the work 35 by the solid line. Standby position H shown
Return to P. Arrow C indicates the forward / backward direction of the work receiver 44.

As shown in FIG. 7, the work collection device 40 includes a slide block 41 having two guide rails 42,
A workpiece receiver 44 slidably mounted in the direction indicated by arrow C on one side 42 and formed on one side thereof with a wire mesh via a support plate 43.
Is rotatably supported, and is rotated by a motor or the like (not shown) toward an upward state shown by a solid line and a horizontal state shown by a virtual line on the near side in FIG.

A pinion 47 rotated by a servomotor 46 is meshed with a rack 45 provided with both ends extending along the other side of the slide block 41. When the slide block 41 is reciprocated in the direction of arrow C together with the work receiver 44 to advance to the forward position shown by the imaginary line and receives the processed work, the work receiver 44 is turned upward and shown by the solid line. When returning to the standby position, the work receiver 44 is turned sideways and the received work is stored in the work receiving box 48.

Since the work receiver 44 is formed of a wire mesh, only the work 35 can be separated by passing the cutting oil or fine cutting powder flowing down with the work 35. However, if the work collecting device 40 quickly moves the work receiver 44 to the advance position FP before the cut-off processing of the work 35 is completed, large chips during the processing enter the work receiver 44, Separation from the work 35 becomes difficult.

For this reason, it is desirable that the end of the parting-off operation by the parting-off tool 33 and the completion of the advance of the work receiver (hereinafter referred to as “separator”) 44 for receiving the processed work 35 be simultaneously performed. Predicts the advance speed of the separator and controls the separator to start moving forward at a predetermined time after the start of the cut-off process with the cut-off tool. It is difficult, and if the completion of the advance of the separator is later than the completion of the parting-off process, the work cannot be received. I often did it.

Therefore, in this embodiment, the execution end waiting according to the present invention is applied, and the execution start timing determination system in which the execution start timing of each block is temporally continuous from the start of the program and the execution start timing of each block is predetermined. And a block for controlling the advance of the separator 44 by the work collecting device 40 belonging to the control program of the other system and a block for controlling the parting-off processing by the parting-off tool 33 belonging to the control program of FIG. (In the case of the interpreter system, it is inserted immediately before each block), and the execution end timing of both blocks is synchronized.

FIG. 8 shows an example of a timing chart in that case.
Shown in In FIG. 8, (a) shows the relationship between the change of the feed speed (vertical axis) and the time lapse (horizontal axis) of the X-axis for moving the cut-off tool 33 and (b) of the A-axis for moving the separator 44. Is shown. The X-axis servo motor (not shown) for moving the cut-off tool 33 and the A-axis servo motor 46 for moving the separator 44 forward and backward in this embodiment may be the two motors 23 and 24 in FIG.

At the time point ta, the cut-off byte 33 becomes X = 1.
At the time t after the execution time TA,
At c, X = 0 (the position where the cutting edge of the cutting tool reaches the axis L of the spindle), and the cutoff is completed. Then work 35
And further stop at the position of X = -3 so that no navel remains.

On the other hand, the separator 44 is set at the time t, which is delayed by the time Tc from the advance start time ta of the cut-off tool 33.
b, the forward movement is started from the standby position HP, and the execution time T
At time tc after B, it reaches the forward end position FP, stops for a very short time, starts retreating, and returns to the standby position HP at time td.

In this case, as described above, after the control program is converted into the execution form in advance, the execution time T
A and the advance time TB of the separator are calculated, and the advance start time tb of the separator is calculated before execution by tb = ta + TC = ta + (TA-TB) in the processing of the end wait command described above. Instructions have been added to block executable programs.

Therefore, according to this embodiment, the time when the parting-off process by the parting-off tool 33 is completed and the time when the advance of the separator 44 is completed can be accurately synchronized. It is possible to minimize the entry of swarf and swarf. In particular, when a minute part is cut off, the part (work) and the swarf are mixed and stored in the work receiving box 48 for sorting. Can be prevented from becoming difficult.

FIG. 9 is an explanatory diagram showing an example of setting various execution end waiting commands by the control programs of a plurality of systems in this embodiment. In the figure, a narrow block e indicated by diagonal lines is an end waiting command, a narrow block s indicated by a horizontal line is a start waiting instruction, and a narrow block c indicated by a dotted line is a continuous execution command. The block immediately after each end wait instruction e is a block for synchronizing the execution end timing (referred to as an "end synchronization block").

In FIGS. 9 (a), 9 (b), 9 (d) and 9 (e), the system 1 is the execution start timing determining system. (A) is an execution start timing determination system (system 1)
The execution time TA of the end synchronization block (cutoff) is longer than the execution time TB of the end synchronization block (separator advance) of the system 2 (TA> TB).

In (b), the execution time TA of the end synchronization block of the execution start timing decision system (system 1) is shorter than the execution time TB of the end synchronization block of system 2 (TA <TB).
In this case, going back to the block (outer diameter) one block before the end synchronization block of the execution start timing determination system, the execution start timing of the block is set to ta, and the total execution time of the subsequent two blocks is set to TA. , The execution start timing tb of the end synchronous block (separator advance) of the system 2 is calculated.

In (c), the execution start timing decision system is initially system 3, but is shifted to system 1 by the start waiting command s, and the end synchronization block (cutoff) of system 1 is performed.
And the end synchronization block (separator advance) of system 2 waits for the end of execution. In this case, (TA <TB)
Therefore, going back one block (boring) before the system 3 and setting the execution start time of the block as ta, the execution time of the block (boring) and the execution time of the end synchronization block (cutoff) of the system 1 And the sum of these as TA.

(D) is a case in which if the execution is synchronized with the start wait command s before the end wait command e, the synchronization end by the end wait command will not be established. And informs it (during program check).

In (e), there is a continuous execution command before the end synchronous block (separator advance) of the system 2 and the block one block before (workpiece upward), and these two blocks are continuously executed. . In this case, it is preferable that information on the number of blocks to be executed consecutively with the block is entered in the end wait instruction e. (f) is an example of three systems in which the execution start timing determination system shifts from the system 1 to the system 2 and the block marked with a star is an end synchronization block in which the execution start timing has not been determined.

In the example shown in FIG. 9, the end wait command is all entered immediately before the end synchronous block. However, in the case of the compile method, the end wait instruction may be entered immediately after the end synchronous block. Good. Also, at the time of program check, if there is information on the number of continuous execution blocks in the continuous execution command or the end wait command in the execution start timing determination system, they are incorrectly set and skipped, or if an alarm is generated Good.

In the above-described embodiment, the example has been described in which the parting-off process and the advance of the separator in the NC control panel are synchronized at the execution end timing. However, the present invention is not limited to this, and a plurality of machine tools may be used. This is all the case when it is necessary to terminate one operation of one control axis at a time when the other operation reaches a certain condition. For example, the present invention can be applied to a case where the start / stop of spindle rotation and the opening / closing of a chuck, or the case where processing with a plurality of blades by an end mill is simultaneously completed.

[0074]

As described above, according to the present invention, the waiting time when the control axes of a machine tool having a plurality of control axes are operated in relation to each other is reduced, and the machining time is reduced. It is possible to reduce the time and accurately synchronize the end timing of each operation by the plurality of control axes.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a control device for implementing a method of controlling a machine tool according to the present invention.

FIG. 2 is a flowchart of a prefetch conversion process of a control program by an interpreter method according to the embodiment of FIG. 1;

FIG. 3 is a flowchart of a subroutine of an end waiting command processing of step 4 in FIG. 2;

FIG. 4 is a diagram illustrating a prefetch conversion process of the control program of FIG.
FIG. 4 is an explanatory diagram showing an example in the case of = 3.

FIG. 5 is an explanatory diagram relating to execution start timing calculation of a block of another system in FIG. 3;

FIG. 6 is a plan view of a main part of an NC lathe embodying the present invention.

FIG. 7 is a perspective view of the work collecting device.

FIG. 8 is a timing chart in a case where control is performed so that the end of the parting-off process by the parting-off tool and the completion of the advance of the separator receiving the processed work in the NC lathe shown in FIG. 6 are synchronized.

FIG. 9 is an explanatory diagram showing a setting example of various execution end waiting commands by a plurality of control programs in this embodiment.

[Explanation of symbols]

1: System control unit 2: Input switch 3: Display unit 4: Input / output control unit 5: System control program memory (ROM) 6: System memory (RAM) 7: Control program storage unit (ROM or RAM) 8: Execution format program storage (RAM) 9: Program format conversion unit 10: Execution time calculation unit 11: Execution start timing fixed block identification unit 12: Execution end synchronization unit 13: Control program processing unit 14: Operation control unit 21, 22: Motor control drive units 23, 24: Motor 25: Actuator control drive unit 26: Actuator 27: Sensor input unit 28: Sensor 30: Headstock 31: Spindle 3
2: Guide bush 33: Cut-off tool bit 34: Work material 35: Work piece (work) 40: Work collection device 41: Slide block 44: Work receiver (separator) 46: Servo motor 48: Work receiving box

Continuation of front page (56) References JP-A-5-108122 (JP, A) JP-A-4-324502 (JP, A) JP-A-1-303502 (JP, A) (58) Fields investigated (Int) .Cl. ⁷ , DB name) G05B 19/18-19/46 B23Q 15/00-15/28

Claims (7)

(57) [Claims] 1. A method of controlling a machine tool, comprising: simultaneously executing a plurality of blocks of a control program, and controlling the control axes of a machine tool having a plurality of control axes to operate in association with each other. Converting a plurality of blocks to be executed at least simultaneously into an executable form; calculating respective execution times of the respective blocks converted into the executable form; and Specifying a block that is temporally continuous from the start and whose execution start timing is predetermined; execution start timing and execution time of the specified block; and execution start timing of the plurality of blocks that are simultaneously executed. The execution end timing of the plurality of blocks is synchronized with the execution time of the undetermined block. Calculating and determining the execution start timing of the block whose execution start timing has not been determined, and synchronizing the execution end timings of a plurality of blocks that are simultaneously executed by the control program. Machine tool control method. 2. The machine tool according to claim 1, wherein the control program includes a plurality of control programs, and the plurality of blocks to be executed simultaneously belong to different control programs. Control method. 3. A completion waiting command indicating synchronization of execution completion timing is input to each of simultaneously executed blocks belonging to the plurality of control programs of the plurality of systems, respectively. Machine tool control method. 4. The method according to claim 1, further comprising: a block having the end waiting command and having the execution start timing not determined in advance.
4. The method according to claim 3, wherein one or more blocks are continuously executed with the block having the end waiting command. 5. The control method for a machine tool according to claim 4, wherein a continuous execution command is input in a block that is executed continuously with a block having the end waiting command. 6. The method according to claim 4, wherein information for designating the number of blocks to be executed continuously with the block having the command is entered in the end waiting command. 7. A control device for a machine tool which executes a plurality of blocks of a control program at the same time and controls each control axis of a machine tool having a plurality of control axes to operate in relation to each other. A program format conversion means for converting a plurality of blocks to be executed at least simultaneously into an executable form; an execution time calculating means for calculating an execution time of each block converted into an executable form by the means; Execution start timing determination block specifying means for specifying a block which is temporally continuous from the start of the control program and has a predetermined execution start timing, and execution start timing of the block specified by the means; And an execution time, and an execution start timing of the plurality of blocks to be simultaneously executed. And an execution end synchronization unit that calculates and determines the execution start timing of the block whose execution start timing has not been determined so that the execution end timings of the plurality of blocks are synchronized from the execution time of the block for which the execution start timing has not been determined. A control device for a machine tool, comprising: synchronizing execution end timings of a plurality of blocks simultaneously executed by the control program.