JPH0689109A - Numerical controller - Google Patents

Abstract

PURPOSE:To improve working precision by operating a working according the positioning of a block, judging whether or not the block reaches the block designated position according to the presence or absence of it within an imposition value, designating the different imposition value when it is inadequate and controlling the working. CONSTITUTION:An NC program is stored in a nonvolatile memory 13, and the imposition value for the positioning is inputted by a data input device 14 and stored. The imposition value is set to be a large numeric value which is suited between a fast forwarding and the fast forwarding, fast forwarding and a cutting feeding, and cutting feeding and the fast forwarding for which the high positioning precision is not necessary. Afterwards, an NC device 1 is driven, and a machine is driven. Then, several processings are operated in parallel in the NC device 1, and a CPU 10 time-divides a constant cycle, and processes in parallel the pre-processing of reading one block from the NC program, and preparing an execution form data, execution processing of operating a pulse distribution to each axis by the execution form data, and the other processing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a numerical controller for controlling a machine tool or the like.

[0002]

2. Description of the Related Art In a numerical control device for controlling a machine tool or the like, an NC program stores a path along which a tool travels with respect to a work, and the machine tool or the like is controlled in accordance with the NC program to perform machining. At that time, the numerical controller reads one block of the NC program, and if the command of this block is a movement command for positioning, cutting, etc., it drives the servomotor of each axis according to this command to perform machining such as positioning or cutting. To perform. Then, it is determined whether or not the position designated by the block is reached, whether or not the value of the error register in the servo circuit for driving the servo motor of each axis is within a predetermined value range, that is, the in-position value. If it is within the in-position value, the processing of the next block is started. With the above procedure, the shape is machined into the shape specified by the NC program.

At this time, the smaller the in-position value, the more accurately it is positioned at the designated position.
Although accurate machining can be performed, there is a drawback that the machining time becomes long because it takes time for positioning. Further, if the in-position value is increased, the processing time becomes shorter, but the positioning accuracy becomes rough and the processing accuracy becomes low. Therefore, as a control for changing the in-position value, Japanese Patent Laid-Open No.
As disclosed in Japanese Patent Laid-Open No. 3-206804, a method is known in which two parameters are selected according to the type of movement command currently being processed and the type of movement command of the next block. . This method requires a high positioning accuracy, for example, when a block from cutting feed to cutting feed is between blocks, a small in-position value,
When the block does not require exceptionally high positioning accuracy, for example, between blocks from fast-forward to fast-forward, a large in-position value is used to ensure the required positioning accuracy and shorten the machining time. is there.

[0004]

In the above numerical control method, even when the type of the movement command currently being processed and the type of the movement command of the next block are the same, positioning accuracy may or may not be required. , There is a problem that we can not respond.
That is, for example, during a block from fast-forward to fast-forward, it is instructed to always have a large in-position value. Counterbore machining with rapid traverse As with the case of performing counterbore machining, even between fast traverses and locations requiring positioning accuracy,
If a large in-position value is selected, the tool may interfere with the work and the required machining accuracy may not be obtained.

[0005]

The present invention has been made in order to solve the above-mentioned problems, and it is one of NC programs.
Set the in-position value in the numerical controller that judges that the movement command position commanded by the block has been reached by the value of the error register in the servo circuit being within the in-position value. Setting means, specifying means for specifying an in-position value different from the in-position value set by the setting means on the program together with the movement command, and determining means for judging the presence or absence of the in-position value specified by the specifying means. If the in-position value is determined by the determination means, the specified in-position value is validated, and if the in-position value is determined not to be set by the setting means It is characterized in that it is configured by a replacement means for validating the in-position value.

[0006]

According to the movement command for positioning or cutting the block read by the numerical controller, the servomotors for the respective axes are driven to perform positioning, cutting and other machining. Whether or not the position specified in this block is reached is determined by whether or not it is within the in-position value. Normally, the judgment is made based on the in-position value set by the setting means in advance. If the preset in-position value is unsuitable, a different in-position value is newly specified in the program, and positioning is performed based on the newly-specified in-position value only when the in-position value is newly specified. Processing such as cutting and cutting is controlled.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a main part of a system for executing the numerical control method of the present invention. A numerical control device (hereinafter referred to as NC device) 1 is a central processing unit (hereinafter referred to as CPU) 10,
ROM storing the overall management program of the NC device 1
11. RAM1 used for temporary storage of data
2. A non-volatile memory 13 for storing an NC program for machining and an NC program for setting an in-position value described later, a data input device 14 with a CRT display device for inputting data, Servo circuit 1 for driving servo motors MX, MY, MZ of each axis
It has a servo interface 15 for connecting 7X, 17Y, 17Z, and these are connected by a path 16.

The servo circuits 17X, 17 for each axis
Error registers 18X, 18Y, 18Z in Y, 17Z
A pulse distributed to each axis is input to the axis via the servo interface 15. Further, the position detectors PX, PY provided on the servo motors MX, MY, MZ of the respective axes,
Feedback pulse from PZ is error register 18
The error registers 18X, 18Y, and 18Z are respectively input to X, 18Y, and 18Z, and are controlled and positioned so that the values of the error registers 18X, 18Y, and 18Z become "0". The values of the error registers 18X, 18Y, 18Z, that is, the error amounts εx, εy, εz are the servo interface 1
The error amount is input to 5, and the error amount can be detected.

Next, the operation processing of this embodiment will be described. First, the NC program is stored in the non-volatile memory 13, and the in-position value for positioning is input and stored by the data input device 14. For this in-position value, for example, a large numerical value is set so as to be suitable for fast feed to fast feed, fast feed to cutting feed, and cutting feed to fast feed that do not require exceptionally high positioning accuracy.

After that, the NC device 1 is driven to drive the machine. The NC device 1 performs some processing in parallel,
The CPU 10 time-divisions a certain cycle, reads one block from the NC program, and performs preprocessing for creating execution format data, and execution processing for performing pulse distribution to each axis by the execution format data and other processing in parallel. . Below, an example of pre-processing and execution processing is shown. In the preprocessing, as shown in FIG. 2, one block is read from the NC program (step S1), converted into execution format data (step S2), and the converted execution format data is stored in the preparation register R1. Yes (step S3). Thereafter, it is determined whether the execution register R2 is read for execution and is empty (step S4), and if it is empty, the execution format data of the preparation register R1 is stored in the execution register R2 (step S5). ). In this way, the execution register R2 stores the execution format data of the block to be executed, and the preparation register R1 stores the execution format data of the next block. This process
It is performed every fixed time of a fixed cycle.

In the execution processing, as shown in FIG. 3, one block of execution format data stored in the execution register R2 in the preprocessing is read (step S10), and pulse distribution processing is started for each axis. Then (step S1
1), the error register 18 in the servo circuits 17X, 17Y, 17Z for each axis via the servo interface 15
Distribute pulses to X, 18Y, 18Z. As a result, the servomotors MX, MY, MZ of the respective axes are driven, and the feedback pulses generated from the position detectors PX, PY, PZ accordingly cause error registers 18X, 18Y, 1 to be generated.
8Z is subtracted, and error registers 18X, 18Y, 18
The servo motors MX, MY, MZ of the respective axes are driven so that the error amounts εX, εY, εZ accumulated in Z become “0”.

On the other hand, the CPU 10 recalls the parameter A previously stored in the memory 13 and stores it in the register C (step S12). As described above, this parameter A has a large value and is a numerical value when the relationship between the current block and the next block does not require exceptionally high positioning accuracy. Then, it is necessary to change the in-position value of the parameter A to a small value, and it is determined whether or not there is the set value B designated by the operator on the program (step S13). The set value B is smaller than the parameter A, and is a numerical value when the relationship between the current block and the next block requires high positioning accuracy such as cutting feed to cutting feed. Step S1
If it is determined in step 3 that there is the setting value B, the setting value B is stored in the register C in place of the parameter A (step S
14). If it is determined that the set value B does not exist, the parameter A is stored in the register C as it is.

After that, each error register 18X, 18
Read the error amounts εx, εy, εz from Y, 18Z,
It is determined whether or not the absolute values of the respective error amounts εx, εy, εz are smaller than the in-position value stored in the register C (step S15, step S17, step S1).
9). If it is smaller than the in-position value, the flags FX, FY, and FZ are set to "1" (step S16,
Step S18, Step S20), all flags F
It is determined whether X, FY, FZ are "1" (step S21). When all flags FX, FY, FZ are not "1", all error amounts εx, εy, ε
The servo motors MX, MY, MZ are driven until z becomes smaller than the in-position value. If all the flags FX, FY, FZ are "1" in step S21,
When it is determined that the end point of the block currently being executed has been reached, the flags FX, FY, and FZ are all set to "0" (step S2
2) Then, the process returns to step S10 again to start the processing of the next block stored in the execution register R2.

As described above, when the in-position value is set to a value different from the parameter A which is the in-position value set in advance, a different in-position value B is newly specified on the program, and this new specification is made. If there is an in-position value B that has been set, this in-position value B
Alternatively, when there is no in-position value B, the parameter A is used as it is, so that, for example, when high positioning accuracy is required, no matter what the relationship between the current block and the next block, The in-position value can be reliably reduced, and machining can be performed with high positioning accuracy. Therefore, the in-position value is determined by the type of movement command currently being processed and the type of movement command of the next block, which cannot be handled by the conventional method. It can handle cases where the block movement commands are the same and there are locations that require positioning accuracy and locations that do not.
The in-position value can be decreased when the positioning accuracy is required, and can be increased when the positioning accuracy is not required. Further, since the newly designated in-position value can be selected as an optimum value that achieves the required positioning accuracy, the required positioning accuracy can be obtained accurately.

In the above embodiment, the value of the parameter stored in advance is set to a large value suitable for the case where the relationship between the current block and the next block does not require exceptionally high positioning accuracy, but is limited to this. However, this value is selected from the two numerical values of the parameter D and the parameter E having a value smaller than the parameter D, and the selection is made according to the type of the movement command of the currently executing block and the next block. By doing so, a small value of the parameter E is selected between the cutting feed and the cutting feed, which require accurate positioning, and does not require exceptionally high positioning accuracy. Fast feed to fast feed, fast feed to cutting feed, cutting The parameter D having a large value may be selected during the period from the feed to the fast forward.

[0016]

As described above, according to the present invention, when the movement command position instructed by one block of the NC program is reached, the value of the error register in the servo circuit falls within the in-position value. In a numerical control device that judges and proceeds to the next block, setting means for setting the in-position value and designating means for designating an in-position value different from the in-position value set by the setting means on a program together with a movement command. And a judging means for judging whether or not there is an in-position value specified by the specifying means, and when the judging means judges that the in-position value is specified, the specified in-position value is validated, If it is determined that the position value is not specified, the in-position value set by the setting means will be valid. By this configuration, the problem that arises in the conventional method of uniquely determining the in-position value by the movement command currently being processed and the movement command of the next block is solved, and it is necessary. It is possible to optimally specify the in-position value according to the positioning accuracy to be performed, and it is possible to obtain the optimum processing accuracy.

[Brief description of drawings]

FIG. 1 is a block diagram of a main part of a system of a numerical controller according to an embodiment of the present invention.

FIG. 2 is a flowchart of preprocessing of operation processing according to the embodiment of the present invention.

FIG. 3 is a flowchart of execution processing of operation processing in the embodiment of the present invention.

[Explanation of symbols]

 1 Numerical control device (NC device) 17X, 17Y, 17Z Servo circuit 18X, 18Y, 18Z Error register

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akihiro Takeuchi 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Co., Ltd. (72) Inventor Takeo Kondo 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Co., Ltd.

Claims (1)

[Claims] 1. A numerical control which judges that the movement command position commanded by one block of the NC program is reached by the value of the error register in the servo circuit being within the in-position value, and proceeds to the next block. In the apparatus, setting means for setting the in-position value, designating means for designating an in-position value different from the in-position value set by the setting means on a program together with a movement command, and the in-position designated by the designating means The determining means for determining the presence or absence of a value, and when the determining means determines that the in-position value is designated, the designated in-position value is validated, and it is determined that the in-position value is not designated. In this case, the in-position value set by the setting means is made effective by the replacement means. Numerical control device characterized in that.