JP2780729B2 - Numerical control unit - Google Patents

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, and more particularly, to a machining provided to a numerical controller from an external NC machining program creating device, a built-in NC automatic program creating device, or the like. By preventing the program from being interrupted during cutting, it is possible to prevent a situation in which the machining program is interrupted and the cutting is temporarily stopped, and a cut mark is attached to the cut surface of the workpiece due to the stop of the cutting. The present invention relates to a numerical control device as described above.

[0002]

2. Description of the Related Art FIG. 12 is an explanatory diagram for explaining a method of supplying a machining program to a numerical controller. In the figure, reference numeral 50 denotes a numerical control device (hereinafter referred to as “NC device”), 54 denotes a host computer, and the NC device 5
This is an external NC machining program creation device that performs processing such as generating a machining program to be supplied to the CPU. Hereinafter, based on this FIG.
A method for supplying the machining program generated in the step (1) to the NC device 50 will be described.

A first method for supplying a machining program to the NC device 50 is to create a machining program in an external NC machining program creating device 54 and to copy the created machining program to a maximum of 2 Mbytes ( The processing program is supplied to the NC device 50 by transferring the data to the memory 51 of usually about 100 Kbytes. Thereafter, the NC device 50 reads the machining program from the memory 51 and temporarily stores the machining program in the supply buffer 52, controls the machine tool while reading the machining program from the supply buffer 52, and performs cutting of the workpiece. . This first method is generally called memory driving.

In a second method, a machining program created by an external NC machining program creating device 54 is temporarily stored in a storage medium such as an FD (floppy disk) 55,
A processing program is supplied to the NC device 50 via the CPU 55. The NC device 50 reads a machining program from the FD 55 via the input / output device 56, stores the machining program in the supply buffer 52, controls the machine tool while reading the machining program from the supply buffer 52, and performs cutting of the workpiece. Will be.

A third method is to temporarily record the processing program created by the external NC processing program creating device 54 on a paper tape 57 and supply the processing program to the NC device 50 via the paper tape 57. The NC device 50 reads the processing program recorded on the paper tape 57 via the NC tape reader 53, and
2 to control the machine tool while reading out the machining program from the supply buffer 52, thereby cutting the workpiece.

Further, a fourth method is that the machining program created by the external NC machining program creating device 54 is directly transferred to the NC device 50 without using any storage (recording) medium as in the first to third methods. The processing program is supplied to the NC device 50 by transferring the processing program to the supply buffer 52. The NC device 50 controls the machine tool while reading the machining program from the supply buffer 52. This fourth method is generally a BTR
(Behind Tape Reader) operation, and as shown in FIG.
0, for example, via a communication line 58 such as RS-232-C, and while the NC device 50 receives the machining program created by the external NC machining program creating device 54,
The machine tool is controlled based on the received machining program to cut the workpiece (at this time, the machining program is not stored in the memory 51 of FIG. 12).

The external NC machining program creating device 54 shown in FIG. 12 is constructed using a personal computer or the like, and has a) an automatic program creating function for creating a machining program; Function to store and supply to NC device 50,
c) It has editing and input / output functions for modifying, copying, merging, etc., the machining program. These functions are realized based on prepared software. Note that external N
The C processing program creation device 54 has different specifications for each product, and can realize all of the above functions a) to c), only the function a), only the function b), a) and c).
There are products and the like having only the functions described above.

The automatic program creation function a) is intended to reduce the programming load on the programmer by enabling data to be input interactively. More specifically, the automatic program creation function is used to set the work mounting method, which has been performed manually based on the machining drawing, to set the cutting procedure (process division, depth of cut for roughing / finish cutting and tool path), Selection of cutting tool / tool holder / machine mounting position, determination of cutting conditions (spindle speed / feed speed),
Calculates tool path coordinate values, inputs machining programs,
This is to reduce the labor required for operations such as confirmation of a machining program (particularly, for...).

[0009] One machining program created by using the automatic program creation function includes a "drilling shape", a "milling shape" and a "contouring shape" which can be calculated in a relatively short time. Processing such as "pocket processing shape" which takes a little time and "three-dimensional processing shape" which takes a long time are mixed. Here, it takes less than one second from the start of processing to the generation of a machining program in the case of a "milling shape" which can be calculated in a short time, whereas it takes 30 seconds or more in the case of a "three-dimensional shape" which requires a long time. There are cases. This is because, in the calculation processing for the “three-dimensional processing shape”, a very complicated calculation (four-fold precision floating, trigonometric function, square root operation, etc.) must be performed as compared with the “milling processing shape”.

In order to realize the above-described first to fourth methods, a machining program is created by the automatic program creating function of a), and the processing program stored in a hard disk or the like, which is the function of b) The function to supply to the device 50 "will be used. However, the BTR operation, which is the fourth method, is performed when the machining program created by the external NC machining program creating device 54 is an enormous amount and physically exceeds the capacity of the memory 51, or is erased in the memory 51. When there is a machining program that the user does not want to have and the free area of the memory 51 is small and the amount of the machining program created by the external NC machining program creating device 54 exceeds the free area, the operator can use a storage medium such as the FD 55 or a paper tape. It is used when performing the NC operation via 57 is troublesome.

In general, when a three-dimensional free-form surface is machined in a die working for manufacturing a press working die or a mold working die, the arbitrary curve is formed into a minute straight line in order to process an arbitrary curve. It is common practice to create a machining program (small line segment program) expressing the above-mentioned arbitrary curve as a set of divided straight lines (hereinafter, the length of this minute straight line is referred to as Length)). In this case, since an arbitrary curve is represented as a set of minute straight lines, the amount of data of the machining program becomes enormous, and in many cases, several Mbytes to several tens Mbytes.
e. For this reason, such an enormous amount of machining programs are stored in a maximum of 2 Mbytes (typically 100 Mbytes) shown in FIG.
Kbyte) of memory cannot be stored. In addition, such a huge amount of machining programs are
The method is stored in a storage medium such as the FD 55 as in the method described above, or recorded on the paper tape 57 as in the third method.
Feeding to zero is very cumbersome. Therefore, BT
R operation will be performed.

In the fourth method, the machining program created by the external NC machining program creating device 54 is enormous and physically exceeds the capacity of the memory 51 or does not want to be erased in the memory 51. When the machining program exists and the free area of the memory 51 is small and the amount of the machining program created by the external NC machining program creating device 54 exceeds the free area, the external NC machining program creating device 54 specifies the product specifications. It is used even when there is no function of storing the processing program on a hard disk or the like.

Next, the configuration and operation of the NC device itself that receives the supply of the machining program as described above will be described. FIG. 13 is a block diagram showing a configuration of a conventional NC apparatus for controlling a machine tool. Speed calculating means, 77 is a drive unit, 71 is an NC including the above means
This is a device corresponding to the NC device 50 shown in FIG.

The reception buffer 73 shown in FIG.
This corresponds to the supply buffer 52 shown in FIG. 12, and can store a processing program of about 4000 characters. The communication means 72 shown in FIG.
The processing program is received from the external NC processing program creating device 54 and the NC tape reader 53 shown in FIG. That is, FIG.
Reference numeral 3 denotes a configuration in a case where the processing program is supplied directly from the external NC processing program creating device 54 (in the case of BTR operation) or the NC tape reader 53 shown in FIG. It is shown.

Next, referring to FIG. 13 and FIG.
The operation of the C device 71 will be described. FIG.
6 is a flowchart showing the operation of the NC device 71 shown in FIG. First, when a cycle start is applied to the NC device 71, the NC tape reader connected to the NC device 71 (FIG. 1)
3) or a computer (external NC machining program creation device: not shown in FIG. 13) receives the machining program in the reception buffer 73 via the communication means 72 (S78). Next, the program analysis means 74 analyzes the received machining program (S79), and the speed calculation means 76 calculates the tool feed (interpolation) speed from the analysis result of the program analysis means 74 (S80). Next, the interpolation means 75 executes interpolation processing from the analysis result of the program analysis means 74 and the calculation result of the speed calculation means 76 (S81),
The drive unit 77 drives the motor based on the interpolation data of the interpolation means 75 (S82), and controls a work machine (not shown) to cut the work.

As another NC apparatus, an automatic programming device is incorporated, and the NC program is configured to be able to receive a machining program from the automatic programming device.
There is also a C device. That is, in addition to the above-described first to fourth methods, the NC device can receive a supply of a machining program from an automatic program device incorporated in the NC device.

The automatic program device (hereinafter referred to as "AP") built in the NC device has the same function as the automatic program creation function of the external automatic program creation device 54 described above.
This device aims to reduce the load of programming by a programmer by inputting data interactively. By being built in the NC device, hardware resources (CPU, ROM, RAM, display, keys, etc.) on the NC side can be used as described later with reference to the drawings. Also, there is an advantage that the NC device operator can configure an NC device capable of creating a machining program with its own know-how.

FIG. 15 is a block diagram showing a hardware configuration of an NC device incorporating an AP. In the figure, 30
Is a CPU for controlling and calculating the entire apparatus, and 32 is an NC
NC side R that stores software for executing processing
OM, 34 is a work area at the time of NC processing.
M and 36 are AP-side ROMs for storing software for executing the AP processing, and 38 is an AP-side RAM which is a work area for the AP processing (hereinafter, the NC-side ROM 32 and N
C side RAM 34 is abbreviated as NC side, AP side ROM 36 and A
The P-side RAM 38 is abbreviated as the AP side).

Reference numeral 40 denotes a machining program storage RAM, which functions as various storage buffers for the NC machining program generated on the AP side and the NC machining program input from the input / output unit 42 to be described later. Time,
The NC side fetches and analyzes the program and executes numerical control.

Reference numeral 42 denotes an input / output unit for starting NC operation,
It performs input / output of switches, interpolation functions, and spindle functions from the outside such as C operation suspension from the 42a, input from the key data input section 42b, input / output of NC machining programs to / from the outside, and the like. Reference numeral 44 denotes an external NC machining program creation device corresponding to the external NC machining program creation device 54 shown in FIG. 12, which externally creates an NC machining program using a personal computer or the like, and applies it to the input / output unit 42. This is an external input / output device, unlike the built-in AP-side ROM 36 and RAM 38. Reference numeral 46 denotes a display unit, which displays on the display 46a the display of the operating state on the NC side, the display of automatically determined data on the AP side, and the like. Numeral 48 denotes a drive unit which performs amplification processing and the like on data numerically controlled on the NC side and drives the servo motor 48a.

FIG. 16 is a block diagram showing a flow of signals in the case of performing an NC operation by inputting a machining program from either the AP side or an external NC machining program creating device in the NC apparatus shown in FIG. . In addition,
When receiving the supply of the machining program from the external NC machining program creation device, this corresponds to the BTR operation. In the figure, reference numeral 10 denotes an AP side, and when starting NC operation, A
In the case of the P input mode, an NC machining program is generated and supplied, and set in the supply buffer 16 described later. Reference numeral 12 denotes an external NC machining program creating apparatus, which is generally called an external input / output device, generates and supplies an NC machining program when starting NC operation, and applies the NC machining program to an input / output unit 14 described later. Reference numeral 14 denotes an input / output unit which, when starting the NC operation, starts the external NC machining program creating device 12 if the external device input mode (BTR operation) is used, inputs an NC machining program as output data thereof, and outputs a parity. A check or the like is executed and set in the supply buffer 16 described later.

Reference numeral 16 denotes a supply buffer corresponding to the supply buffer 52 shown in FIG.
It has an NC machining program storage area for storing 250 characters of a 120 character machining program. For example, when the processing program has an average of 15 characters per block, the supply buffer 16 can store the processing program of 15 blocks. And the supply buffer 16
When the NC machining program generated by the AP 10 or the external NC machining program creating device 12 is input, the NC machining program is stored for each block, and the machining program is stored in all NC machining program storage areas (hereinafter, NC machining). The state in which the machining programs are stored in all of the program storage areas is described as “supply buffer 16 becomes“ full ”), and all machining programs are collectively transferred to digestion buffer 20 described later. Digestion buffer 20 for processing program
, The supply buffer 16 becomes empty,
AP side 10 or external NC machining program creation device 12
Is requested, and the machining program is stored in the supply buffer 16 one block at a time. Since the processing program for one block stored in the supply buffer 16 is variable, even if the supply buffer 16 is full, an empty area may be generated at the end thereof.

Reference numeral 20 denotes a digestion buffer, which, like the supply buffer 16, is composed of a plurality of blocks of NC machining program storage areas. The digestion buffer 20 inputs and stores the NC machining program from the supply buffer 16 and sends data to the NC side 22 described later one block at a time, and becomes empty when all data is sent to the NC side 22.
It requests the supply buffer 16 to transfer data again.

Reference numeral 22 denotes an NC side, which extracts an NC machining program from the digestion buffer 20 one block at a time, analyzes the program, and performs an interpolation operation or the like corresponding to the tool feed speed. In addition, a control signal such as an NC operation start is notified to the AP side 10 or the external NC machining program creation device 12. 24
Is a drive unit, which drives the servo motor 24a by amplifying the numerical control data interpolated and calculated by the NC side 22 and the like.

Next, the digestion operation during the NC operation of the NC side 22 will be described with reference to the flowcharts shown in FIGS. Here, the digestion operation means that the NC machining program is taken out from the digestion buffer 20 in units of one block, analyzed, and interpolation calculation or the like is performed in accordance with the tool feed speed. Digestion also means this digestion operation. First, the NC operation is started from the NC side 22 to the AP side 10 or the external NC machining program creation device 12, and the AP side 10 is started.
Alternatively, a machining program is input from the external NC machining program creation device 12, and the supply buffer is filled. Next, it is determined whether the digestion buffer 20 is empty (S40),
If it is not empty, it jumps to step 50 through the route of A, and if it is empty, it proceeds to step 42. Next, it is determined whether or not the supply buffer 16 is empty (S42).
If it is empty, the process goes through the route of B, and a series of processing ends.
Conversely, if not empty, the contents of the supply buffer 16 are transferred to the digestion buffer 20 (S44).

Next, one block (for example, G01X-100.Y-
100. ;) Is taken out (S50). Next, the moving amount (X-10) corresponding to the commanded tool feed speed (F100).
0. Y-100. ) Is performed (S52).
After that, the data subjected to the interpolation calculation is output to the drive unit 24 (S54), and a series of processes is ended. After that, the driving unit 24
Operates the servo motor to perform a predetermined movement (X-100.Y-100.) At a predetermined speed (F100), and upon completion, the digestion operation according to steps 40 to 54 is repeated again.

As described above, when there is an NC machining program in the digestion buffer 20, the program passes through the route A, and when there is no NC machining program, the contents of the supply buffer 16 are transferred to the digestion buffer 20 in step 44. Have been.

FIG. 18 shows an example of the NC device with a built-in AP.
AP when receiving the supply of machining program from P side 10
6 is a timing chart showing timings of a side 10 and an NC side 22. Normally, one CPU is used for the NC device with built-in AP.
30 (see FIG. 15) performs AP-side processing and NC-side processing.
In this case, generally, the priority of the NC-side processing is high (foreground processing), and the AP processing is executed using the idle time (background processing). This is the NC side 22
The reason for this is that since the interpolation calculation processing in the above requires high real-time performance, interrupting the interpolation calculation processing on the NC side 22 for the processing on the AP side 10 greatly affects the system. Specifically, as shown in FIG. 18, while the NC side (digestion side) is digesting (A1 to An), the AP side (supply side) uses the idle time to perform the next NC processing. The program (B) is created. Then, when the digestion (An) on the NC side is completed, the next data (B1) can be digested immediately from the next timing, so that a command is not interrupted between buffers. Similarly, while the NC side is digesting the NC machining program (B), the next NC machining program (C) is further changed to A.
Create on P side. AP side 1 in NC device with built-in AP
When the machining program is supplied from 0, such processing is repeatedly executed.

Note that one block (for example, A
When the interpolation time of 1) is long (the moving amount is large or the tool feed speed is small), the time until the activation of the next block (A2) becomes long, and the running time on the AP side increases accordingly. Conversely, when the interpolation time of one block on the NC side is short (the moving amount is small or the tool feed speed is large), the time until the start of the next block is short, and the running time on the AP side is narrowed accordingly. On the AP side, an NC machining program can be created in a single time for a simple shape (for example, a milling square shape), but a long calculation time is required for a complex shape (for example, a pocket irregular shape). It costs.

Other reference documents relating to the present invention include a "numerical control method" disclosed in Japanese Patent Application Laid-Open No. 1-320505 and a "numerical control device" disclosed in Japanese Patent Application Laid-Open No. 59-116809. ", JP-A-60-93
No. 513 discloses a "data input / output device of an application system in a numerical control device" and Japanese Patent Application Laid-Open No. 62-120953 discloses a "synchronous operation method for copying".

[0031]

However, in the above-described conventional NC device, the machining program to be given to the NC device from the external NC machining program creating device, the automatic program device, or the like is interrupted for the reason described below. Cutting may be paused during cutting feed,
There is a problem in that the temporary stop of the cutting causes scratches called cutter marks on the cut surface of the workpiece. Hereinafter, this problem will be described in detail.

First, the cutter mark will be described. FIG. 19 is an explanatory diagram illustrating a tool path of the NC device. If the machining program is interrupted during the cutting process and there is no more machining program to be digested in the NC device, the process of cutting the workpiece by moving the tool based on the machining program of the previous block is performed. Since the processing program for the next block has not been transferred when the processing is completed, the tool stops during the cutting processing as shown in FIG. 19 (the cutting processing is interrupted). At this time, since the tool is rotating for cutting the workpiece, the cut surface of the workpiece is damaged. These scratches are called cutter marks. The tool trajectory diagram shown in FIG. 19 shows the previous block An (G01Xx2Yy2Ff).
Since the tool stops at the end point of 2;) and the tool is rotating during that time, the next block B1 (G03Xx3Yy3Ii3J
j3;) shows that a cutter mark has been attached.

Next, the reason why the machining program supplied to the NC device is interrupted and the cutting (tool) is temporarily stopped at the time of cutting feed and the above-mentioned cutter mark is attached will be described. In the NC device 71 described with reference to FIGS. 13 and 14, when the machining program amount to be cut by the cutting is larger than the machining program amount supplied via the communication unit 72, the cutting is performed as it is. Continuing, the machining program in the reception buffer 73 shown in FIG. 13 is not consumed, and the cutting is temporarily stopped until the machining program of the next block is transferred. Therefore, the cutter mark described with reference to FIG. 19 is attached to the cut surface of the workpiece.

The reason why the amount of the machining program to be supplied cannot keep up with the amount of the machining program to be consumed is that the transfer speed of the machining program when supplying the machining program to the reception buffer 73 via the communication means 72 is reduced. There is. Another reason is that when the machining program is supplied to the NC device 71 while the machining program is created by the external NC machining program creating device 54 shown in FIG. While the NC processing program creation device 54 is creating a machining program for forming a shape that requires a lot of time to create a machining program to be supplied to the NC device 71, such as a three-dimensional machining shape of a ball end mill, the machining of the NC device 71 is performed. There are cases where the supply of the program cannot be made in time.

In the case of receiving a machining program from the AP 10 in the NC apparatus described with reference to FIGS.
The side 10 is N, for example, a ball end mill 3D machining shape.
When a machining program for forming a shape that requires a lot of time to create a machining program to be supplied to the C side 22 is being created, the NC side 22 suspends cutting and waits until the creation of the machining program is completed. Must be. Specifically, as shown in FIG.
After the C side 22 performs the cutting process based on the machining program of the block An, if the AP side 10 is creating the machining program of the block B to be executed next on the NC side 22, the block An and the next The cutting process stops with the block B1, and the cutting process is kept waiting (supply-side time shortage state). As a result, in the case of the cutting command, the command is completely interrupted, and the tool stops at the end point of the previous block An (G01Xx2Yy2Ff2;) as shown in the tool path diagram in FIG.
(G03Xx3Yy3Ii3Jj3;), there is a flaw called a cutter mark.

The state in which the NC side 22 waits is shown in FIG.
6 and the flowchart shown in FIG. 17, the digestion buffer 20 is empty by the digestion operation on the NC side 22, and the supply buffer 16 is empty. The completion state is a state that continues for a while.

In the case of receiving the machining program from the external NC machining program creation device 12 (BTR operation) instead of the AP 10 in the NC device described with reference to FIGS. Cutting may be temporarily stopped for the same reason as in the case of the NC device 71 described with reference to FIG. 14, and also in this case, a cutter mark is attached to the cut surface of the workpiece.

The present invention has been made in order to solve the above-mentioned problems, and the timing of waiting for the completion of buffer setting is intentionally changed by the digestion operation on the NC side to easily interrupt the cutting feed command. It is a first object of the present invention to obtain an NC device that eliminates the occurrence of cutter marks and prevents the occurrence of cutter marks.

Further, even when the amount of the machining program consumed by the cutting becomes larger than the amount of the machining program supplied by the communication means, the cutting feed rate is controlled so that the machining program in the buffer is not lost. It is a second object of the present invention to obtain an NC device which can be controlled so as not to be temporarily stopped and a cutter mark is not attached to a cut surface of a workpiece.

[0040]

An NC apparatus according to the present invention includes a supply buffer for storing a plurality of blocks of a numerical control machining program supplied from an automatic programming device or an external input / output device, and a machining buffer from the supply buffer. An NC including an intermediate buffer to be transferred, a digestion buffer to which a machining program is transferred from the intermediate buffer, and a numerical control unit that extracts a machining program for numerical control from the digestion buffer, executes numerical control, and operates a driving unit. In the apparatus, the numerical control unit includes a digest buffer final data judging unit, an intermediate buffer empty judging unit, a fast-forward judging unit, and a digest buffer outside the final data, the intermediate buffer is empty, and the numerical control is performed when fast-forwarding. Locking means for interlocking the start of block execution of the machining program It is intended to Bei.

Further, a supply buffer for storing a plurality of blocks of a numerical control processing program supplied from an automatic programming device or an external input / output device, an intermediate buffer to which a processing program is transferred from the supply buffer, and a processing from the intermediate buffer. A digestion buffer to which a program is transferred, a numerical control unit that extracts a machining program for numerical control from the digestion buffer, executes a numerical control, and operates a driving unit, a cutting feed reduction enable / disable flag and a speed reduction coefficient parameter set by an operator In the NC apparatus having the following, the numerical control unit includes a digestion buffer final data determination unit, an intermediate buffer empty determination unit, a cutting feed determination unit, a cutting feed reduction possibility flag determination unit, and a digestion buffer that stores the final data. Outside and the intermediate buffer is empty and cutting feed, and , In which and a control means for reducing by multiplying the speed reduction coefficient parameter a tool feed rate of cutting feed reduction possibility flag ON at numerical control machining program.

Also, a receiving buffer for receiving the machining program via the communication means, a program analyzing means for analyzing the machining program received by the receiving buffer, and a control speed calculated based on the analysis result of the program analyzing means. An NC device for controlling a machine tool or the like, comprising: a speed calculating unit that performs interpolation processing based on a result of the speed calculating unit and the program analyzing unit.
The remaining amount of the machining program received in the receiving buffer via the communication means is detected, and when the remaining amount of the machining program is smaller than a predetermined boundary value, the feed rate specified by the machining program is set to the Speed override output means for calculating and outputting override information for decelerating according to the remaining amount, wherein the speed calculation means receives the override information from the speed override output means and processes the override information from the program analysis means. Feed speed information specified by a program is input, and based on the input override information and feed speed information information, an override feed speed of the machining program is calculated. And the solution from the program analysis means. Enter the results, based on the override feed rate and analysis results are the input, and executes the interpolation processing.

Also, a receiving buffer for receiving the machining program via the communication means, a program analyzing means for analyzing the machining program received by the receiving buffer, and a control speed calculated based on the analysis result of the program analyzing means. An NC device for controlling a machine tool or the like, comprising: a speed calculating unit that performs interpolation processing based on a result of the speed calculating unit and the program analyzing unit.
Data setting means for setting a minute line segment length, a communication speed, the number of characters per block, and the like are provided. And the like, and a clamp speed calculating means for calculating the clamp speed based on such data and outputting the clamp speed information to the speed calculating means in order to limit the processing speed.

Further, a receiving buffer for receiving the machining program via the communication means, a program analyzing means for analyzing the machining program received by the receiving buffer, and a control speed calculated based on the analysis result of the program analyzing means. An NC device for controlling a machine tool or the like, comprising: a speed calculating unit that performs interpolation processing based on a result of the speed calculating unit and the program analyzing unit.
An average character number detection unit that detects an average number of characters per block from the processing program received in the reception buffer; and an effective reception speed calculation unit that calculates an effective reception speed from the number of characters received in the reception buffer. An average minute line length detecting unit for detecting an average minute line length from the analysis result of the program analyzing unit; and It is provided with a clamp speed calculating means for calculating a clamp speed.

[0045]

In the NC apparatus according to the present invention, an intermediate buffer is provided between the supply buffer and the digestion buffer.
The NC side always determines the empty state of the intermediate buffer, and if it is empty, the block to be executed next (for example, B1 in FIG. 18)
Is fast-forward (G00 mode), interlock the start of block execution, wait until the intermediate buffer is filled via the supply buffer, and then adjust the timing to start block execution after filling. That is, the block execution start interlock means at the time of fast-forward (G00 mode) waits until the intermediate buffer is filled, and after that, returns to the normal processing so that the cutter mark is not added in the subsequent cutting feed block. Even if it waits until the intermediate buffer is filled, the cutter is not cut due to rapid traverse, so that there is no cutter mark in the block.

If the block to be executed next (for example, B1 in FIG. 18) is a cutting feed (G01, G02, G03 mode), the tool feed speed is automatically reduced.
As a result, the one block interpolation time is lengthened, the supply side executes the NC machining program in the supply buffer until the time required for setting, and if the intermediate buffer is filled via the supply buffer, the tool is returned to the commanded tool feed speed. Make adjustments. That is, the means for reducing the interpolation speed at the time of cutting feed (G01, G02, G03 mode) causes the intermediate buffer to be filled during the interpolation of the reduced block.
After being buried, the processing is returned to the normal processing so that the cutter mark is not attached to the subsequent cutting feed block.

Further, in the NC apparatus according to the present invention, the speed override output means calculates the override of the cutting speed from the remaining amount of the processing program in the reception buffer, and controls the cutting speed via the speed calculation means. Even when the amount of the machining program to be digested by the cutting is greater than the supplied amount of the machining program, the cutting is not stopped and the occurrence of the cutter mark is prevented.

Further, data such as minute line segment length, communication speed and the number of characters per block are previously stored in the memory by the data setting means, and the clamp speed calculation means reads out the data from the memory and sets the clamp speed. By limiting the cutting speed via the speed calculating means, even if the machining program amount to be digested by cutting is greater than the supplied machining program amount, the cutting is not temporarily stopped. To prevent the occurrence of cutter marks.

Further, the average number of characters detecting means detects the average number of characters per block from the machining program received in the receiving buffer, and the effective receiving speed calculating means determines the effective number of characters from the number of characters received in the receiving buffer. The receiving speed is calculated, and the average minute line length detecting means detects the average minute line length from the analysis result of the program analyzing means. Clamp speed calculation means calculates a clamp speed based on data from the average character number detection means, effective reception speed calculation means, and average minute line length detection means, and limits the cutting speed via the speed calculation means. Accordingly, even if the machining program amount to be digested by the cutting is larger than the supplied machining program amount, the cutting is not temporarily stopped and the generation of the cutter mark is prevented.

[0050]

Embodiment 1 An embodiment of an NC apparatus according to the present invention will be described below with reference to the drawings. The hardware configuration of the NC device according to the first embodiment is exactly the same as the conventional NC device with a built-in AP shown in FIG. FIG. 1 is a block diagram showing a signal flow in the case of the NC operation. In the figure, 10 is A
On the P side, at the time of starting the NC operation, if it is in the AP input mode, an NC machining program is generated and supplied, and set in the supply buffer 16 described later. Reference numeral 12 denotes an external NC machining program creating apparatus, which is generally called an external input / output device, generates and supplies an NC machining program when starting NC operation, and applies the NC machining program to an input / output unit 14 described later. Reference numeral 14 denotes an input / output unit, which starts the external NC machining program creation device 12 if the external device is in the external device input mode when starting the NC operation, inputs an NC machining program as output data thereof, performs a parity check, and the like. It is set in the supply buffer 16 described later.

Reference numeral 16 denotes a supply buffer, which is an NC machining program storage area of a plurality of blocks.
The machining program is stored for each block, and when it is full, it is transferred to an intermediate buffer 18 described later. When the machining program is transferred to the intermediate buffer 18, the supply buffer 16 becomes empty, data transfer is requested to the AP side 10 or the external NC machining program creation device 12, and the machining program is stored again in the supply buffer 16 block by block. To go.

Reference numeral 18 denotes an intermediate buffer, which is newly provided in the present invention and is an NC machining program storage area of a plurality of blocks.
Transfer to 0. When the machining program is transferred to the digestion buffer 20, the intermediate buffer 18 becomes empty, so that data transfer is requested to the supply buffer 16. Also, the empty state information of the intermediate buffer 18 is sent to the NC side 22 described later,
It is used for timing adjustment of block execution start and the like.

Numeral 20 denotes a digestion buffer, which is an NC machining program storage area of a plurality of blocks, which receives an NC machining program from the intermediate buffer 18 and which is described later.
The data is sent to the C side 22 one block at a time, and when the data is digested, it becomes empty and requests the intermediate buffer 18 for the data again.

Reference numeral 22 denotes an NC side, which extracts the NC machining program from the digestion buffer 20 one block at a time, analyzes the program, and performs an interpolation operation or the like corresponding to the tool feed speed. In addition, the empty state of the intermediate buffer 18 is determined, interlock for starting block execution is performed, and the tool feed speed is reduced to easily eliminate breaks in the cutting feed command, thereby preventing generation of a cutter mark. In addition, a control signal such as an NC operation start is notified to the AP side 10 or the external NC machining program creation device 12. Numeral 24 denotes a drive unit which drives the servo motor 24a by amplifying the numerical control data interpolated and calculated by the NC side 22.

Reference numeral 26 denotes a key data input unit, where an operator sets various parameters of the NC device. Numeral 28 denotes a cutting feed reduction parameter, which is newly provided in the present invention, and has a cutting feed reduction enable / disable flag fg and a speed reduction coefficient k1 to kn for each block. Set via.

Next, the digestion operation of the NC side 22 during the NC operation will be described with reference to the block diagram shown in FIG. 1 and the flowchart shown in FIG. First, the NC side 22 sends the NC side to the AP side 10 or the external NC machining program creation device 12.
The operation is started, a machining program is input from the AP side 10 or the external NC machining program creating device 12, and the supply buffer is filled.

Then, it is determined whether the digestion buffer 20 is empty (S10).
Jump to 6, and conversely, if empty, intermediate buffer 18
Is determined (S12). Here, if it is empty, jump to step 16 through route C, and conversely,
If it is not empty, the contents of the intermediate buffer 18 are digested into the buffer 2
0 (S14). Next, it is determined whether the intermediate buffer 18 is empty (S16). If it is not empty, the process jumps to step 21 via the D route.
6 is determined (S18). Here, if empty, the process jumps to step 21 through the D route, and if not empty, the contents of the supply buffer 16 are transferred to the intermediate buffer 18 (S20).

Next, it is determined whether or not the digestion buffer 20 is empty (S21). If it is empty, the processing immediately ends through the E route. A determination is made (S22). Here, the final data of the machining program includes an end of record indicating the end, and it is determined whether or not a code called an end of record indicating the end of the NC machining program exists in the digestion buffer 20. By doing so, it can be determined whether or not the content of the digestion buffer 20 is the final data.

After the end-of-record, which is the final data, is created in the AP 10 or the external NC machining program creating device 12, the process for creating the machining program is not performed. As a result, NC
When the side 22 performs the digestion operation of the final data, the digestion buffer 20 contains the final data but the supply buffer 1
6 and the intermediate buffer 18 will be "empty". In the first embodiment, as described later, the machining program of one block to be digested next in the digestion buffer 20 when the intermediate buffer 18 is empty is fast-forwarded (G0
In the case of 0), a process of interlocking the execution start of the block is performed to prevent a cutter mark from being attached to the cut surface of the workpiece. Therefore, if it is not determined in step 22 whether or not the contents of the digestion buffer 20 are the last data, if the last data of the digestion buffer 20 is fast-forward (G00), the start of the block is interlocked, Digestion will not be performed. This state in which the digestion operation of the final data is not performed is called a deadlock state.
Is intended to prevent deadlock from occurring when the intermediate buffer 18 is empty.

Therefore, when the data in the digestion buffer 20 is the final data, if the digestion operation of the final data has been performed, the processing is completed, and the flow branches to the step 50 which is the normal processing through the F route. Conversely, if it is not the final data, the process proceeds to step 24.

Next, it is determined whether or not the intermediate buffer 18 is empty, which is a feature of the present invention (S24). If it is not empty, the process branches to step 50, which is a normal process, through the F route. One block (for example, G00X-100. Or G01X-100.Y-100.F100;) of the NC processing program is extracted from the digestion buffer 20 (S26).

Next, it is determined whether the cutting feed or the rapid feed is performed (S28). In the case of the rapid feed (G00 mode), the block execution start which is a feature of the present invention is interlocked (S30), and the E route is performed. To end the processing without executing the interpolation. In other words, when there is no machining program in the intermediate buffer 18 (when the machining program is likely to be interrupted) and the machining program of the block to be executed next in the digestion buffer 20 is fast-forward, the block execution start of the machining program is interrupted. By locking, the tool is stopped in a state where the tool is separated from the workpiece, and waits until the machining program is transferred to the intermediate buffer 18. As a result, it is possible to prevent a situation in which the machining program is interrupted, the cutting process is temporarily stopped, and a cutter mark is attached to the cut surface of the workpiece in advance. Also,
Since the tool is stopped at a position away from the workpiece, no cutter mark is attached to the cut surface of the workpiece. This will be described later in detail with reference to FIGS. When the execution of the block is interlocked, the process waits for the machining program to be stored in the intermediate buffer 18, and when the machining program is stored in the intermediate buffer 18, the interlock is released and the normal machining process is started. Will be returned to.

On the other hand, cutting feed (G01, G02, G03)
Mode), the content of the cutting feed reduction enable / disable flag fg of the cutting feed parameter 28 set by the operator is O.
It is determined whether or not N (S31), and if it is ON, a tool feed speed reduction process which is a feature of the present invention is performed (S32). Conversely, if it is OFF, the process branches to step 52, and the tool feed reduction process is performed. Not performed. The purpose of this judgment is to reduce the cutting conditions by lowering the tool feed speed depending on the material of the work piece, and the degree of adverse effect on the cutting surface is higher than the cutter mark (for example, aluminum material with high ductility). ).

In step 32, the commanded tool feed speed is reduced each time the sheet passes. In this embodiment,
By multiplying the speed reduction coefficient k for each block of the cutting feed reduction parameter 28 set by the operator by the commanded tool feed speed, a new tool feed speed is obtained as follows. Decreased tool feed speed = commanded tool feed speed * speed reduction coefficient k The speed reduction coefficient k is k1 for the first block (the first pass through step 32), k2 for the second block (the second pass through step 32), ... Kn is used for the n-th block and thereafter (n-th and subsequent passes of step 32). Usually 100
%>K1>k2>...>Kn> 0% set by the operator. For example, the speed reduction coefficient k1
= 50%, k2 = 25% if command tool feed rate F10
When the value is 0, the tool feed speed decreases as F50 in the first block and F25 in the second block.

[0065] After the tool feed rate in step 32 is decreased, running Interpolation operation corresponding to the tool feed speed (S5
2) As a result, the interpolation time for one block becomes longer, and it takes time until the NC processing program of the supply buffer 16 is set on the supply side, thereby preventing interruption of the command on the digestion side. As a result, it is possible to prevent the cutting from being stopped during the cutting process and the cutter mark from being attached to the cut surface of the workpiece. This processing is repeated until the intermediate buffer 18 is filled via the supply buffer 16 in the above step 20. After the filling, the processing is passed through the F route from step 24 to the tool feed speed commanded in step 50 and subsequent steps, which is the normal processing. It is for returning.

In step 50, one block of the NC processing program is extracted from the digestion buffer 20 in the normal processing route (for example, G01X-100.Y-10).
0. ;). Then, in the next step 52, the moving amount (X-100.Y-10) corresponding to the tool feed speed (F100).
0. ) Is performed. Step 3 above
Block (for example, the command F
An interpolation operation of 50% of 100 (F50) is also performed. afterwards,
The interpolated data is output to the drive unit 24 (S54).
A series of processing ends. Thereafter, the drive unit 24 causes the servo motor 24a to move a predetermined distance (X-100.Y-100) at a predetermined speed (F100 or F50).
Is repeated.

As described above, when there is an NC machining program in the digestion buffer 20, the process goes through the route C. When there is no NC machining program, the process goes to step 14 and the contents of the intermediate buffer 18 are transferred to the digestion buffer 20. When the NC machining program is present in the intermediate buffer 18, the program passes through the route D and when there is no NC machining program, the content of the supply buffer 16 is transferred to the intermediate buffer 18 via step 20. If the intermediate buffer 18 is not empty, the process goes through the F route and the step 5
The normal operation of digesting one block after 0 is performed. If the intermediate buffer 18 is empty, if it is fast-forward (G00 mode), the flow goes to step 30 to interlock the start of block execution and stop the tool for cutting the workpiece at a position away from the workpiece. Then, when the intermediate buffer 18 is no longer empty, the interlock is released and the process returns to the normal cutting process. On the other hand, if the intermediate buffer 18 is empty and the next digested block in the digestion buffer 20 is the cutting feed (G01, G02, G03 mode), step 32 is executed.
To reduce the tool feed speed, take time to set the machining program for NC in the supply buffer 16 on the supply side, eliminate breaks in commands on the digestion side, and easily execute cutter mark prevention. .

FIG. 3 shows an NC with a built-in AP according to the present invention.
4 is a timing chart showing timings of an AP side 10, an intermediate buffer 18, and an NC side 22 of the device. In the NC device with a built-in AP, one CPU 30 (FIG.
5) performs the AP-side processing and the NC-side processing. Generally NC
The priority of the side process is high, and the AP process runs using the idle time.

In the steady state shown in FIG.
While the side (digestion side) is digesting (A1 to An), the next NC processing program (B) has already been stored in the intermediate buffer 18, and at the same time, the AP side (supply side) utilizes the idle time. The next NC machining program (C) is created. Then, when the digestion (An) of the NC side 22 is completed, the next data (B1) can be digested immediately from the next timing, so that the command is not interrupted between the buffers.

Note that one block (for example, A
When the interpolation time of 1) is long (the moving amount is large or the tool feed speed is small), the time until the activation of the next block (A2) becomes long, and the running time on the AP side increases accordingly. Conversely, when the interpolation time of one block on the NC side is short (the moving amount is small or the tool feed speed is large), the time until the start of the next block is short, and the running time on the AP side is narrowed accordingly. On the AP side, an NC machining program can be created in a single time for a simple shape (for example, a milling square shape), but a long calculation time is required for a complex shape (for example, a pocket irregular shape). It costs.

The supply-side time shortage state G0 shown in FIG.
In the 0 mode, the intermediate buffer 18 is empty and A
When the P side 10 is still creating the next machining program (B) for NC, if the NC side 22 is A1 to A at t1,
If n is executed, a command break occurs between the cutting feed An and the cutting feed B1, and a cutter mark may be generated. As a preventive measure, A1 is fast-forward (G00
In the case of (mode), the AP side 10 completes the creation of the next NC machining program (B), and the NC side 22 until t2 at which the NC machining program (B) is transferred to the intermediate buffer 18.
Has interlocked the execution of A1, and
The digestion operation of A1 is started at t2 where the next machining program (B) for NC is entered, and the cutting feed An and the cutting feed B1 are performed.
In order to prevent a break in the command, a cutter mark is prevented. It should be noted that the fast-forward (G00) block does not need to wait until the intermediate buffer 18 is filled.
Since cutting is not performed as in the tool path diagram of the G00 block, there is no cutter mark in the block.

The supply side time shortage state G0 shown in FIG.
1, G02, G03 mode, the intermediate buffer 1
When the NC side 22 is empty and the AP side 10 is creating the next NC machining program (B), if the NC side 22
When the interpolation calculation is performed for A1 to An according to the command speed, the command is interrupted between the cutting feed An and the cutting feed B1, and a cutter mark may be generated. As a preventive measure, when A1 is the cutting feed (G01, G02, G03 mode), the AP side 10 completes the creation of the next NC machining program (B) and transfers the NC machining program (B) to the intermediate buffer 18. Since the NC side 22 lowers the tool feed speed until the time t4, the interpolation time becomes longer. As a result, when the creation of the next NC machining program (B) has been completed on the AP side 10, the NC side 22 is still executing the interpolation processing of A. Then, the data is transferred to the intermediate buffer 18 at the time t4 to be in a steady state, so that the command is not interrupted between the cutting feed An and the cutting feed B1, thereby preventing the cutter mark.

By reducing the tool feed speed, only the tool feed speed is reduced halfway as shown in the tool trajectory diagram of the blocks G01, G02 and G03 in FIG. There is no command break between them and no cutter mark is attached. When the execution of A1 is interlocked at time t3 shown in FIG. 3C as in the G00 mode of FIG. 3B, the cutting feed Zn and the cutting feed A1 are interlocked.
Since the command is interrupted and a cutter mark is added, the processing differs between A1 in rapid feed and cutting feed.

It should be noted that FIG. 3 and FIG.
Although the effectiveness of the present invention in the case where the processing of (1) is delayed has been described, the present invention is not limited to the case where the processing of the AP side 10 is delayed, and the case where the processing of the external NC machining program creating device 12 is delayed. It is clear that the present invention works effectively even when the supply of the machining program is delayed.

As described above, in the NC device according to the first embodiment, the intermediate buffer 18 is empty and the digestion buffer 20
When the machining program of the next block to be executed is fast-forward (G00), the block execution start of the machining program is interlocked and the tool is processed by waiting for the machining program to be transferred to the intermediate buffer 18. Since the cutting can be stopped in a state of being separated from the object and waiting for the transfer of the machining program, the cutting can be interrupted in a state where the cutting surface of the workpiece does not have a cutter mark, and the transfer of the machining program can be waited. Therefore, it is possible to prevent a situation in which the machining program is interrupted, the cutting is temporarily stopped, and a cutter mark is attached to the cut surface of the workpiece.

If the intermediate buffer 18 is empty and the machining program of the block to be executed next in the digestion buffer 20 is cutting feed (G01, G02, G03), the tool feed speed is reduced by multiplying by the speed reduction coefficient parameter. By doing so, the execution time of one block on the NC side 22 is lengthened, and the time required for the supply side to transfer the machining program to the supply buffer 16 can be gained. The cutter mark can be prevented from being attached to the cutting surface.

Embodiment 2 FIG. 5 is a block diagram showing a configuration of an NC apparatus (Embodiment 2) according to the present invention. In the figure, reference numerals 71 to 75 and 77 denote the same components as those of the conventional device shown in FIG. 13 and perform the same operations. Here, 83 is the reception buffer 7
3 is a speed override output unit that calculates the override of the cutting speed from the remaining amount of the machining program and outputs the override information to the speed calculation unit 76a. Reference numeral 76a is a speed calculating means for calculating a cutting speed from the result of the program analyzing means 74 and the result of the speed override output means 83.

Next, the operation of the NC unit 71 according to the second embodiment will be described with reference to FIGS. FIG. 6 is a flowchart showing the operation of the NC device 71 shown in FIG. In the figure, when a cycle start is applied to the NC device 71, a processing program is received from the tape reader or a computer (not shown) connected to the NC device 71 to the reception buffer 73 via the communication means 72 (S).
84). Next, the program analyzing means 74 analyzes the received machining program (S85), and the speed override means 83 calculates an override of the cutting speed from the remaining amount of the machining program in the receiving buffer 73 according to the following equation (1) (S85). S86).

[0079]

(Equation 1)

Here, A is the override, B is the current value of the remaining amount of the machining program, and C is the boundary value of the remaining amount of the machining program for which the override is valid, and these are determined in advance. For example, the current value B of the remaining amount of the machining program is 100 bytes, and the boundary value C of the remaining amount of the machining program is 20 bytes.
Assuming 0 bytes, override A is 50%. Also, if the current value B of the remaining amount of the machining program is 300 bytes and the boundary value C of the remaining amount of the machining program is 200 bytes, the override A is 150%, but if it exceeds 100%, the override A is 100%. And

That is, when the override A is less than 100%, it means that the amount of the machining program in the supply buffer 73 has decreased, and as described later, the cutting feed speed is determined using the obtained value of the override A. To reduce the rate at which the machining program in the supply buffer 73 is digested. In other words, the fact that the amount of the machining program in the supply buffer 73 has decreased means that the NC device 7
Since it means that the amount of the processing program being digested is greater than the amount of the processing program supplied to 1, if cutting is continued at the same cutting feed rate,
Since the machining program in the supply buffer 73 is lost, the cutting is temporarily stopped and a cutter mark is attached to the cut surface of the workpiece. Therefore, in the NC device 71 of the second embodiment, the override A is obtained, and the cutting feed speed is reduced according to the obtained value.
By controlling the balance between the amount of the machining program received through the communication means 72 and the amount of the machining program being digested, the machining program is prevented from being lost from the supply buffer 73, and This is to prevent the cutter mark from being attached to the cut surface of the workpiece.

On the other hand, if the override A is 100% or more, it means that a sufficient amount of the machining program exists in the supply buffer 73, and even if the cutting is advanced at a predetermined cutting feed speed. Since there is no fear that the machining program is lost from the supply buffer 73, the processing is performed at a normal cutting feed speed.

Next, the speed calculating means 76a calculates the tool feed speed from the result of the program analyzing means 74 (S8).
7) The speed calculating means 76a determines whether or not the override as the output result of the speed override output means 83 is 100% (S88). If the override is 100%, the tool feed speed calculated in step 87 is output to the interpolation means 75. That is, 100% override
In the case of, the amount of the machining program supplied to the NC device 71 and the amount of the machining program digested by the NC device 71 are balanced, and the cutting is advanced at the cutting feed speed given by the machining program. I will.

On the other hand, if the override is less than 100%, the override speed is calculated according to the following equation (2) (S89). That is, when the override is less than 100%, the amount of the machining program supplied to the NC device 71 and the amount of the machining program digested by the NC device 71 are not balanced, and the NC device 71 digests the amount. Since it means that the amount of the machining program executed is large, the feed rate for reducing the cut feed rate is calculated by multiplying the obtained feed A by the machining program by the obtained override A.

[0085]

(Equation 2)

Here, A is an override, D is an override speed, and E is a tool feed speed. Next, the interpolation means 7
5 executes an interpolation process based on the analysis result of the program analysis unit 74 and the calculation result of the speed calculation unit 76a (S90), and the driving unit 77 drives the motor based on the interpolation data of the interpolation unit 75 (S91). Control a machine tool not shown.

As described above, the NC device 71 according to the second embodiment
According to the above, by controlling the cutting feed rate based on the remaining amount of the machining program in the reception buffer 73, the machining program amount supplied to the NC device 71 and the machining program amount digested by the NC device 71 are balanced. Therefore, when the amount of the machining program digested by the cutting is larger than the amount of the machining program supplied via the communication means 72, the cutting feed rate is controlled to reduce the amount of the machining program digested by the cutting. Can be done. Therefore, it is possible to prevent a situation in which the machining program in the supply buffer 73 is lost, and the situation where the cutting is temporarily stopped and a cutter mark is attached to the cut surface of the workpiece is generated.

When the supplied machining program amount is larger than the digested machining program amount, the amount by which the cutting feed speed is reduced is gradually reduced, and the process returns to the normal processing.

Further, since the override feed speed is obtained in accordance with the remaining amount of the machining program received in the supply buffer 73 and the driving unit 77 is controlled at the obtained override feed speed, the feed speed is smoothly changed without extremely changing. As a result, it is possible to prevent a situation in which a large load is temporarily applied to the tool. Incidentally, when the remaining amount of the machining program is smaller than a predetermined boundary value set in advance, it is possible to set a fixed value override, for example, 50% override.
There is a problem that the feed rate changes extremely and a heavy load is temporarily applied to the tool.

Further, in the above-described embodiment, the boundary value C of the remaining amount of the machining program is fixed. However, the value may be changed by operating the NC unit 71. The same effects as in the above embodiment can be obtained.

[Embodiment 3] FIG. 7 is a block diagram showing a configuration of an NC apparatus (Embodiment 3) according to the present invention. In the figure, reference numerals 71 to 75 and 77 denote the same components as those of the conventional device shown in FIG. 13 and perform the same operations. Here, 92 is a data setting means for setting the minute line segment length, the communication speed, the number of characters per block, and the like. 93 is stored with data such as the minute line segment length, the communication speed, the number of characters per block, and the like. Memory 94, a clamp speed calculating means for calculating a clamp speed which is an upper limit value of a cutting speed based on a minute line segment length, a communication speed and the number of characters per block stored in the memory 93, and 76b a program analysis Means 7
4 is a speed calculating means for calculating a cutting speed from the result of No. 4 and the result of the clamp speed calculating means 94.

FIG. 8 is an example of a screen display on the display device of the NC device 71 shown in FIG. In the figure, 101 is a display frame, 102 is an input / output device parameter display screen, 10
Reference numeral 3 denotes a data setting unit; 104, a menu display unit and menu keys for displaying operation menus such as "input", "output", and "copy"; 105, communication speed; 106, the number of characters per block; Length, stop bit 108, and character length setting items 109, respectively.

Next, the operation of the NC unit 71 according to the third embodiment will be described with reference to FIGS. FIG. 9 is a flowchart showing the operation of the NC device 71 shown in FIG. First, the operator operates the NC device 71 to display the communication speed (105), number of characters / block (106), minute line segment length (mm) (107), and stop bit (108) of the display screen shown in FIG. When the character length (109) is set (S110), the data setting means 92 stores each set data in the memory 93. Next, when a cycle start is applied to the NC device 71, a processing program is received from the tape reader or a computer (not shown) connected to the NC device 71 to the reception buffer 73 via the communication means 72 (S111). The program analyzing means 74 analyzes the processed machining program (S112).
The clamp speed calculating means 94 reads the data of the communication speed, the stop bit, the character length, the number of characters per block, and the minute line segment length from the memory 93, and calculates the clamp speed according to the following equation 3 (S1).
13).

[0094]

(Equation 3)

Here, J is the clamping speed, F is the minute line segment length, G is the communication speed, H is the number of characters per block, L is the character length, M is the stop bit, and K is the coefficient. (L + M + 1) represents the number of bits of one character on the communication path.

The basis of the above equation (3) will be described below. The moving distance (cutting distance: minute line segment length) of the tool based on the machining program of one block is represented by F (mm / bloc).
k), the number of characters of the machining program per block is H
(Byte / block). In addition, the machining program (the number of characters) processed by the program
(Bytes / sec) and the cutting feed rate is V (mm / min)
Then, the relationship between V and Cp can be expressed as in the following Expression 4.

[0097]

(Equation 4)

Here, Cp / H is the program analysis means 7.
4 indicates the number of blocks to be processed in one second, and F × (Cp /
H) represents the distance (speed) that the tool moves in one second.

Therefore, Cp is

(Equation 5) It can be expressed as.

That is, the machining program (the number of characters) supplied via the communication means 72 is
If it is more than the machining program (number of characters) processed by
Since the machining program in the reception buffer 73 disappears and cutting is temporarily stopped and a cutter mark is not attached to the machining surface of the workpiece, the supplied machining program (the number of characters) is set to N (bytes / second). If

(Equation 6) And the clamping speed J is

(Equation 7) It can be expressed as.

When the communication is in an ideal state, that is, when the communication means 72 receives the machining program without interruption and the machining program is transferred to the reception buffer 73, N
Is represented as

(Equation 8) By substituting Equation 8 into Equation 7, Equation 3 can be obtained.

Subsequently, returning to the description of FIG. 9, the speed calculating means 76b calculates the tool feed speed in the same manner as in the conventional device (S
114). Then, the speed calculator 76b compares the clamp speed, which is the calculation result of the clamp speed calculator 94, with the tool feed speed (interpolation speed> clamp speed) (S11).
5) If the tool feed speed is equal to or less than the clamp speed, the tool feed speed is output to the interpolation means 75. Conversely, if the tool feed speed is higher than the clamp speed, the tool feed speed is replaced with the clamp speed (S116) and output to the interpolation means 75. Next, the interpolation means 75 is used by the program analysis means 7.
An interpolation process is executed based on the analysis result of Step 4 and the calculation result of the speed calculation unit 76b (S117), and the driving unit 77 drives the motor based on the interpolation data of the interpolation unit 75 (S11).
8) Control a machine tool (not shown).

As described above, according to the NC device 71 of the third embodiment, the data setting means 92 for setting the minute line segment length, the communication speed, the number of characters per block, and the like are provided. The speed calculation means 7 calculates a clamp speed based on data such as a minute line segment length, a communication speed, and the number of characters per block, which are set in advance, and limits the clamp speed information to the processing speed.
6b, the speed calculating means 76b compares the clamping speed, which is the calculation result of the clamping speed calculating means 94, with the tool feed speed (interpolation speed> clamp speed), and outputs the tool feeding speed. Is smaller than or equal to the clamp speed, the tool feed speed is output to the interpolation means 75. If the tool feed speed is higher than the clamp speed, the tool feed speed is replaced with the clamp speed and output to the interpolation means 75. Even if the amount of the machining program supplied to the controller exceeds the amount of the machining program to be digested by the NC device 71, the amount of the machining program to be digested is reduced by controlling the tool feed speed so as not to be higher than the clamping speed. Therefore, the reception buffer 73
It is possible to prevent the occurrence of a situation in which the middle processing program disappears during the cutting, the cutting is temporarily stopped, and a cutter mark is attached to the cut surface of the workpiece.

In other words, by balancing the amount of the machining program supplied to the NC device 71 with the amount of the machining program digested by the NC device 71, the machining program in the reception buffer 73 does not run out during cutting. As a result, it is possible to prevent the cutting from being temporarily stopped due to the absence of the machining program in the reception buffer 73, and as a result, it is possible to prevent the cutter mark from being attached to the cut surface of the workpiece. it can.

Fourth Embodiment FIG. 10 is a block diagram showing a configuration of an NC apparatus (fourth embodiment) according to the present invention. In the figure, reference numerals 71 to 75 and 77 denote the same components as those of the conventional device shown in FIG. 13 and perform the same operations. Here, 93a is a memory for storing the clamp speed calculated by the clamp speed calculation means 94a, and 120 is an average character number detection means for detecting the average number of characters per block from the processing program received in the reception buffer 73. And 121, an effective receiving speed calculating means for calculating an effective receiving speed from the number of characters received in the receiving buffer 73, and 122, an average minute line length detecting means for detecting an average minute line length from the analysis result of the program analyzing means 74. Means. Reference numeral 94a denotes a clamp speed calculating means for calculating a clamp speed from the results of the average character number detecting means 120, the effective receiving speed calculating means 121, and the average minute line length detecting means 122, and 76b denotes a speed calculating means. The configuration is exactly the same as that described above, and the same operation is performed.

Next, referring to FIGS. 10 and 11,
An operation of the NC device 71 according to the fourth embodiment will be described. FIG.
11 is a flowchart showing an operation of the NC device 71 shown in FIG. When the cycle start is performed on the NC device 71, the processing program is received in the reception buffer 73 via the communication means 72 from a tape reader or a computer (not shown) connected to the NC device 71 (S12).
3). Next, the program analysis means 74 analyzes the received processing program (S124), and the average character number detection means 120 counts the number of characters per block of the processing program received by the reception buffer 73, for example, The average number of characters for each 100 blocks is calculated (S125), and the calculated number is notified to the clamp speed calculation means 94a.

Next, the effective receiving speed calculating means 121 calculates the effective value of the receiving speed, which is the number of characters received in one second, by counting the number of characters received and the receiving time for every 100 blocks, for example. S126) Notify to the clamp speed calculation means 94a. Next, the average minute line segment length detecting unit 122 detects the minute line segment length between one block from the analysis result of the program
The average minute line segment length for each 0 block is calculated (S12
7) Notify the clamp speed calculation means 94a. Thereafter, the clamp speed calculation means 94 a outputs the average character per block, which is the output result of the average character number detection means 120, and the effective reception speed and average minute line length detection means 122, which is the output result of the effective reception speed calculation means 121.
The clamping speed is calculated from the average minute line segment length as the output result according to the following equation 9 (S128).

[0108]

(Equation 9)

Here, J is the clamping speed, F is the minute line segment length, G is the communication speed, H is the number of characters per block, and N is the receiving speed. It should be noted that Equation 9 is used in Example 3.
The equation is the same as the equation 7 described above, and the basis for deriving the equation 9 is as described in the third embodiment.

Next, the clamp speed calculating means 94a reads out the clamp speed of the previous calculation result stored in the memory 93a and compares it with the clamp speed which is the calculation result of Equation 9 (S129). If the calculated clamping speed is lower than the previous calculated clamping speed, the current clamping speed is stored in the memory 93a (S130). With the above operation, the minimum value of the clamp speed is output to the speed calculating means 76b.

Thereafter, the speed calculating means 76b calculates the tool feed speed in the same manner as in the conventional apparatus (S131), and the speed calculating means 76b compares the clamp speed calculated by the clamp speed calculating means 94a with the tool feed speed (interpolation). (Speed> clamp speed) (S132). If the tool feed speed is equal to or lower than the clamp speed, the tool feed speed is output to the interpolation means 75. Conversely, if the tool feed speed is higher than the clamp speed, the tool feed speed is replaced with the clamp speed (S1).
33) Output to the interpolation means 75. Next, the interpolation means 75 calculates the analysis result of the program analysis means 74 and the speed calculation means 76.
An interpolation process is executed based on the calculation result of b (S134), and the driving unit 77 drives a motor based on the interpolation data of the interpolation means 75 (S135) to control a work machine (not shown).

As described above, according to the NC device 71 of the fourth embodiment, the average character number detecting means 120 for detecting the average number of characters per block from the processing program received by the reception buffer 73 and the reception buffer 73 An effective receiving speed calculating means 121 for calculating an effective receiving speed from the number of characters received; an average minute line length detecting means 122 for detecting an average minute line length from the analysis result of the program analyzing means 74; Means 120, effective receiving speed calculating means 121, and mean minute line segment detecting means 1
By providing the clamp speed calculating means 94a for calculating the clamp speed based on the data from the CPU 22, the speed calculating means 76b compares the clamp speed, which is the calculation result of the clamp speed calculating means 94a, with the tool feed speed (interpolation speed> If the tool feed speed is equal to or lower than the clamp speed, the tool feed speed is output to the interpolating means 75. If the tool feed speed is higher than the clamp speed, the tool feed speed is replaced with the clamp speed and the interpolation means 75 is used. Output to the NC device, the amount of the machining program supplied to the NC
Even if the amount of the machining program to be extinguished by the device 71 is exceeded, the amount of the machining program to be extinguished is reduced by controlling the tool feed speed not to be higher than the clamping speed. Can be prevented from occurring during the cutting, the cutting is temporarily stopped, and a cutter mark is attached to the cut surface of the workpiece.

In other words, by balancing the amount of the machining program supplied to the NC device 71 and the amount of the machining program digested by the NC device 71, the machining program in the reception buffer 73 does not run out during cutting. As a result, it is possible to prevent the cutting from being temporarily stopped due to the lack of the machining program in the reception buffer 73, and as a result, it is possible to prevent the cutter mark from being attached to the cut surface of the workpiece. it can.

[0114]

As described above, according to the present invention, the NC
An intermediate buffer is provided between the supply buffer and the digestion buffer of the apparatus, and the NC-side processing includes a digestion buffer final data determination unit, an intermediate buffer empty determination unit, and a fast forward (G00)
Mode) By providing a judgment means and a means for interlocking the start of block execution at the time of rapid traverse, when the intermediate buffer is empty and the machining program of the next block to be executed in the digestion buffer is fast traverse (G00 mode). Since it is possible to interlock the start of block execution of the machining program, stop the tool away from the workpiece, and wait for the machining program to be transferred to the intermediate buffer,
Since the start of block execution can be adjusted and the command on the supply side that supplies the machining program for NC is interrupted, there is an effect that a cutter mark generated on a cutting surface during cutting feed can be easily prevented.

Further, an intermediate buffer and a speed reduction coefficient parameter set by an operator are provided between the supply buffer and the digestion buffer of the NC unit, and the NC side processing includes an intermediate buffer empty determination unit and cutting feed (G01, G02). , G03
Mode) By providing a judgment means and a means for reducing the speed by multiplying the tool feed speed by a speed reduction coefficient parameter at the time of cutting feed, the machining program of a block to be executed next in the digestion buffer is empty when the intermediate buffer is empty. In the case of cutting feed (G01, G02, G03 mode), the execution time of one block on the NC side becomes longer by lowering the tool feed speed by multiplying by the speed reduction coefficient parameter, and the supply side stores the machining program in the supply buffer. Since the time until the transfer can be gained, the interpolation time can be adjusted, and N
There is an effect that the cutter mark generated on the cutting surface at the time of cutting feed can be easily prevented because the supply side command for supplying the machining program for C is interrupted.

Further, the speed override output means calculates the cutting speed override from the remaining amount of the processing program in the receiving buffer and controls the cutting speed via the speed calculating means, so that the cutting can be performed. Even when the machining program amount is larger than the machining program amount supplied by the communication means, there is an effect that it is possible to prevent cutting to be temporarily stopped and a cutter mark from being attached to the workpiece with a very simple configuration. In other words, by controlling the cutting feed rate based on the remaining amount of the machining program in the reception buffer, the machining program amount supplied to the NC device and the machining program amount digested by the NC device can be balanced. Therefore, when the machining program amount processed by the cutting is larger than the processing program amount supplied via the communication means, the cutting feed rate is controlled to reduce the processing program amount processed by the cutting. . Therefore, it is possible to prevent a situation in which the machining program in the supply buffer is lost, and the situation where the cutting is temporarily stopped and a cutter mark is attached to the cut surface of the workpiece is generated.

Further, data such as minute line segment length, communication speed, and the number of characters per block are previously stored in the memory by the data setting means, and the clamp speed calculation means reads out the data from the memory, and sets the clamp speed. Is calculated, and the speed calculating means compares the clamping speed, which is the calculation result of the clamping speed calculating means, with the tool feed speed (interpolation speed>
If the tool feed speed is lower than the clamp speed, the tool feed speed is output to the interpolation means. If the tool feed speed is higher than the clamp speed, the tool feed speed is replaced with the clamp speed and output to the interpolation means. NC
Even if the amount of the machining program supplied to the machine exceeds the amount of the machining program to be digested by the NC device, the amount of the machining program to be digested is reduced by controlling the tool feed speed not to be higher than the clamping speed. Therefore, it is possible to prevent a situation in which the machining program in the reception buffer is lost during the cutting, the cutting is temporarily stopped, and a cutter mark is attached to the cut surface of the workpiece. Further, data such as a minute line segment length, a communication speed, and the number of characters per block are previously stored in a memory by a data setting unit, and a clamp speed calculation unit reads the data from the memory and calculates a clamp speed. Therefore, the operator does not need to consider the optimum clamping speed for the BTR operation processing, and need only be aware of the operating conditions and communication conditions. Further, since the cutting speed is limited by the clamp speed, the speed is not reduced during the cutting, which is particularly effective when cutting a workpiece that cannot be reduced during the cutting.

The average character number detecting means detects the average number of characters per block from the processing program received in the receiving buffer, and the effective receiving speed calculating means calculates the effective receiving speed from the number of characters received in the receiving buffer. The average minute line length detecting means detects the average minute line length from the analysis result of the program analyzing means, and the average minute line length detecting means, the effective reception speed calculating means, and the average minute line length detecting means The clamp speed calculation means calculates the clamp speed based on the data of (1), and the speed calculation means compares the clamp speed calculated by the clamp speed calculation means with the tool feed speed (interpolation speed> clamp speed). If the tool feed speed is lower than the clamp speed, the tool feed speed is output to the interpolation means. Since the feed speed is replaced with the clamp speed and output to the interpolation means, even if the amount of the machining program supplied to the NC device exceeds the amount of the machining program digested by the NC device, the tool feed speed is higher than the clamp speed. Since the amount of the machining program to be digested is reduced by controlling so that it does not become, the machining program in the reception buffer disappears during cutting and cutting is paused,
It is possible to prevent a situation in which a cutter mark is attached to the cut surface of the workpiece. Further, the average character number detecting means detects the average number of characters per block from the machining program received in the receiving buffer, and the effective receiving speed calculating means calculates the effective receiving speed from the number of characters received in the receiving buffer. The average minute line length detecting means detects the average minute line length from the analysis result of the program analyzing means, and the data from the average character number detecting means, the effective receiving speed calculating means, and the average minute line length detecting means Based on the clamp speed calculation means to calculate the clamp speed,
Since the cutting speed is limited using the minimum value, there is an effect that the cutting speed can be limited according to the actual operating conditions and communication conditions.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a signal flow during operation in an NC device according to the present invention.

FIG. 2 is a flowchart showing a digestion processing operation during operation of the NC device according to the present invention.

FIG. 3 is a timing chart showing the digestion processing operation during the operation of the NC device according to the present invention.

FIG. 4 is an explanatory diagram showing a tool path of the NC device according to the present invention.

FIG. 5 shows the configuration of an NC apparatus according to the present invention (second embodiment).
FIG.

6 is a flowchart showing an operation of the NC device shown in FIG.

FIG. 7 shows a configuration of an NC apparatus according to the present invention (third embodiment).
FIG.

FIG. 8 is an explanatory diagram showing an example of a display screen of the NC device shown in FIG. 7;

9 is a flowchart showing an operation of the NC device shown in FIG.

FIG. 10 is a block diagram showing a configuration (Example 4) of an NC apparatus according to the present invention.

11 is a flowchart showing an operation of the NC device shown in FIG.

FIG. 12 is an explanatory diagram for describing a method of supplying a machining program to an NC device.

FIG. 13 is a block diagram showing a configuration of a conventional NC device.

FIG. 14 is a flowchart showing the operation of a conventional NC device.

FIG. 15 is a block diagram showing a hardware configuration of the present invention and a conventional NC device.

FIG. 16 is a block diagram showing a signal flow during operation of a conventional NC device.

FIG. 17 is a flowchart showing a digestion processing operation during operation of a conventional NC device.

FIG. 18 is a timing chart showing a digestion processing operation during operation of a conventional NC device.

FIG. 19 is an explanatory diagram showing a tool path of a conventional NC device.

FIG. 20 is a timing chart showing a digestion processing operation during the operation of the conventional NC apparatus.

[Explanation of symbols]

10 Automatic programming side (AP side), 12 External N
C processing program creation device, 14 input / output unit, 16 supply buffer, 18 intermediate buffer, 20 digestion buffer, 22 numerical control side (NC side), 24 drive unit, 26
Key data input section, 28 Cutting feed drop parameter,
30 CPU, 32 NC ROM, 34 NC RA
M, 36 AP side ROM, 38 AP side RAM, 40
RAM for processing program storage, 42 input / output unit, 44 external NC processing program creation device, 46 display unit, 48 drive unit, 50 NC device, 51 memory, 52 supply buffer, 53 NC tape reader, 54 external NC processing program creation device, 55 floppy disk, 56
I / O device, 57 paper tape, 58 communication line, 71N
C device, 72 communication means, 73 reception buffer, 74
Program analysis means, 75 interpolation means, 76 speed calculation means, 76a speed calculation means, 76b speed calculation means,
77 drive unit, 78 speed override output means, 79
Data setting means, 83 speed override output means, 92 data setting means, 93 memory, 94 clamp speed calculation means, 94a clamp speed calculation means, 1
01 display frame, 102 input / output device parameter display screen, 103 data setting section, 104 menu display section / menu key, 105 communication speed, 106 character count, 107 minute line segment length, 108 stop bit, 1
09 character length setting item, 120 average character number detecting means, 121 effective receiving speed calculating means, 122 average minute line segment length detecting means

Claims (5)

(57) [Claims] 1. A supply buffer for storing a plurality of blocks of a numerical control machining program supplied from an automatic programming device or an external input / output device, an intermediate buffer to which a machining program is transferred from the supply buffer, and machining from the intermediate buffer. In a numerical control device having a digestion buffer to which a program is transferred and a numerical control unit that extracts a numerical control processing program from the digestion buffer and executes a numerical control to operate a driving unit, the numerical control unit includes a digestion buffer. The final data determination means, the intermediate buffer empty determination means, the fast forward determination means, and the digestion buffer is out of the final data, the intermediate buffer is empty, and the block execution start of the numerical control machining program is interlocked at the time of fast forward. A numerical control device comprising: a lock unit. 2. A supply buffer for storing a plurality of blocks of a numerical control machining program supplied from an automatic programming device or an external input / output device, an intermediate buffer to which a machining program is transferred from the supply buffer, and machining from the intermediate buffer. A digestion buffer to which a program is transferred, a numerical control unit for taking out a numerical control machining program from the digestion buffer and executing a numerical control to operate a drive unit, a cutting feed reduction enable / disable flag and a speed reduction coefficient parameter set by an operator In the numerical control device having the following, the numerical control unit includes a digestion buffer final data determination unit, an intermediate buffer empty determination unit, a cutting feed determination unit, a cutting feed reduction possibility flag determination unit, Outside the data, the intermediate buffer is empty, and cutting feed, and A control means for reducing the tool feed speed of the numerical control machining program by a speed reduction coefficient parameter when the cutting feed reduction enable / disable flag is ON. 3. A receiving buffer for receiving a machining program via communication means, a program analyzing means for analyzing the machining program received by the receiving buffer, and calculating a control speed based on an analysis result of the program analyzing means. Speed calculation means, and an interpolation means for executing interpolation processing from the results of the speed calculation means and the program analysis means, and in a numerical control device for controlling a machine tool or the like, a numerical value received by a reception buffer via the communication means. Override information for detecting the remaining amount of the machining program and, when the remaining amount of the machining program is smaller than a predetermined boundary value set in advance, reducing the feed rate specified by the machining program according to the remaining amount. Comprising speed override output means for calculating and outputting
Inputting override information from the speed override output means, inputting feed speed information instructed by a machining program from the program analysis means, and overriding the machining program based on the input override information and feed speed information information. A feed speed is calculated, and the interpolation means inputs an override feed speed from the speed calculation means and an analysis result from the program analysis means, and performs the interpolation based on the input override feed speed and the analysis result. A numerical control device for performing processing. 4. A receiving buffer for receiving a machining program via communication means, a program analyzing means for analyzing the machining program received by the receiving buffer, and calculating a control speed based on an analysis result of the program analyzing means. A numerical control device for controlling a machine tool or the like, comprising: a speed calculating means for performing the interpolation processing based on a result of the speed calculating means and the program analyzing means; Data setting means for setting the number of characters and the like, and calculating the clamp speed based on the data such as the minute line segment length, the communication speed and the number of characters per block preset in the memory by the data setting means. A clamp speed calculating means for outputting the clamp speed information to the speed calculating means for limiting a machining speed. A numerical control device comprising a step. 5. A receiving buffer for receiving a machining program via a communication means, a program analyzing means for analyzing the machining program received by the receiving buffer, and calculating a control speed based on an analysis result of the program analyzing means. A numerical control device for controlling a machine tool or the like, comprising: a speed calculating means for performing interpolation processing based on a result of the speed calculating means and the program analyzing means; Average character number detection means for detecting an average number of characters per block; effective reception speed calculation means for calculating an effective reception speed from the number of characters received in the reception buffer; and an average minute line based on an analysis result of the program analysis means. An average minute line length detecting means for detecting a length, and a means for detecting the average number of characters. A numerical control device comprising a clamp speed calculating means for calculating a clamp speed based on data from a step, an effective receiving speed calculating means and an average minute line segment detecting means.