JPH0325292B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Application and Prior Art The present invention relates to a numerical control device for a machine tool or the like.

The present invention relates to a numerical control device that does not process a workpiece continuously but intermittently, such as a drilling machine that drills a plurality of holes.

For example, in a numerical control device for a drilling machine that drills a plurality of holes in a workpiece W as shown in _{FIG .} x ₁ , y ₁ , z ₁ ), and in the next block B ₂ , it is rapidly traversed in one direction, for example, the Z-axis direction, to position P ₂ on the surface of the workpiece W, and then moves to position P ₂ (x ₁ , y ₁ , z ₂ ), the hole is drilled to the hole bottom position P ₄ , then it is reversed and returned to the position P ₇ , which is equal to the drilling start position P ₁ , and then automatically or The operator moves to the next drilling position by inputting a command to move to the next step while checking the state of the hole. This kind of operation is performed, but as shown in Figure 2, if drilling is stopped due to a power outage or reset at the point indicated by SZ during drilling from position P ₂ to position P ₃ , the drilling will be restarted. When starting, in the incremental method, if machining is continued as it is, the processing shown in FIG. 3 will be performed. That is, the second
Machining from the stop position SZ to the end point P3 of the block _B3 in the figure is not performed, and the machining of the block _B4 from the position _P3 to _P4 is performed at the same time as _machining is restarted. As a result, the hole does not reach the specified position, but becomes shallower by the distance l between position SZ and P ₃ in Figure 2.
In addition, the tool does not return to the drilling start position P ₁ ,
As shown in FIG. 3, it returns to point P ₇ ', which is shifted by l in the Z-axis direction.

Therefore, in order to avoid the above-mentioned machining errors, conventionally the process is stopped in the middle of machining such as hole machining, and when restarting it, the program is restarted from the beginning, or the sequence number is searched and the process is started at an appropriate location. I had to go back and redo the process, or I had to go back manually.
This restart work is wasteful and inefficient.

Purpose of the Invention The purpose of the present invention is to improve the above-mentioned drawbacks, and to automatically determine the restart position no matter where the machining is, and to continue machining from the position before stopping. An object of the present invention is to provide a processing restart control device.

Configuration of the Invention FIG. 4 is an explanatory diagram of the configuration of the present invention. The non-volatile memory MEM stores the latest information such as modal data, a specific code attached to the hole start positioning block, such as a sequence number, and the drilling start position in the case of an incremental method. When a machining restart command is input from the key input means MDI such as a cycle start button, the restart machining start positioning block indexing means BDT starts machining of the suspended machining based on the specific code stored in the non-volatile memory. The positioning block is indexed from the NC program, and the contents of the block next to the machining start positioning block (position data, modal data, etc.) are decoded, and the tool stop block detection means PST determines the tool position indicated by the block. Compare the tool stop position indicated by the current value counter COU, and if the tool stop position is larger, decode the next block.
As before, compare the tool position indicated by the block with the tool stop position. If the incremental method is used, the read position command values of each block are added up and the added value is compared with the tool stop position. This process is performed until the tool position commanded by each block exceeds the tool stop position.
Detect tool stop position block. Then, when the block is detected, the control means CNT processes the block according to the modal data read during the above processing up to the position indicated by the block, and from the next block onwards, the processing is performed according to the normal processing flow. It is something that can be done.

Examples Examples of the present invention are shown in Figs. 1 and 5 to 8.
This will be explained with reference to the figures.

FIG. 5 is a block diagram showing an example of the hardware configuration of the apparatus according to the present invention, in which 1 is a microcomputer, 2 is a CMOS memory that stores the NC machining program, and this is a CMOS memory that stores command data and this. It may also be configured with a tape reader. 3 is a writable and readable non-volatile memory;
4 is a manual data input device, 5 is its interface circuit, 6 is an axis control circuit, 7 is a servo amplifier,
8 is a motor motor, 9 is a position detector, and 10 is a current value counter composed of a non-volatile element. Note that the axis control circuit 6, servo motor amplifier 7, servo motor 8, position detector 9, and current value counter 1
0, only a uniaxial portion is shown for convenience of explanation.
Further, FIG. 6 is a flowchart showing an example of the software configuration of the apparatus according to the embodiment of the present invention.

Microcomputer 1 has CMOS memory 2
The NC machining program stored in the machine is read and decoded block by block, and the axis control circuit 6
is controlled to drive the servo motor 8 via the servo amplifier 7 to execute predetermined numerically controlled machining, and in parallel, the process shown in FIG. 6 is performed.

In other words, when the modal data is changed during the execution of the NC machining program, the stored information in the modal information storage area of the non-volatile memory 3 is rewritten, and the modal data at the time of current machining is always stored in the non-volatile memory 3.
(steps S1, S2). Even in conventional numerical control devices, modal data at the time of current machining is generally stored in a memory or the like, so the above processing can be performed by writing the contents of the memory or the like into the non-volatile memory 3. Of course, the memory and the like may be constructed of nonvolatile memory and the like.
Furthermore, the latest modal data may be stored each time a machining start positioning block, which will be described later, is executed.

The microcomputer 1 also determines whether the block to be executed is a machining start positioning block (step S3). This is done by attaching a sequence number, for example, N7000 to N7999, as a specific code to the machining start positioning block in advance, and identifying this sequence number.
For example, if the positioning block for hole #4 in Figure 1 is _B1 , then as shown in Figure 7, the sequence number of N7004 is assigned to this block _B1.
Leave it on. Now block B ₁ from the program
is read, and when the microcomputer 1 determines that it is the positioning block to start hole machining, it stores the sequence number in the sequence number storage area of the non-volatile memory 3, or updates the previous content, and sets the position to start hole machining. That is, the end point position of the hole machining start positioning block is detected, and this position is stored in the hole machining start position storage area of the nonvolatile memory 3, or the previous contents are updated (steps S4, S5). Note that if the absolute method is used, there is no need to memorize the hole machining start position.

Further, since means for detecting the tool position are already known, the tool position can be detected using these methods. In FIG. 5, this is done by reading the contents of a current value counter 10 which is counted up and down by the output pulses of the position detector 9.

The above-described processing is continued during processing (step S6). Therefore, if machining is interrupted due to some reason such as a power outage or a stop operation, the modal data at the time of machining interruption will be stored in the nonvolatile memory 3.
The sequence number and hole machining start position of the hole machining start positioning block that has been executed or is about to be executed immediately before machining is interrupted are stored.

Therefore, as shown in Fig. 7, if the machining is interrupted during machining, that is, as shown in Fig. 7 A, the hole machining stops on the way to the hole bottom P ₄ (for example, at point SZ). An example of the restart process of the present invention will be explained by taking as an example a case where the machine stops during the return trip from the bottom of the hole _P4 (for example, point SZ). First, the cycle start button provided on the machine side When the operator presses or uses a separate key input means to command restart of machining, the process shown in FIG. 8 is performed. That is, the microcomputer 1 searches the machining program for a sequence number that matches the sequence number stored in the non-volatile memory 3, or in the example shown in FIG. Detect block _B1 (step S7). If it is an incremental method, the above non-volatile memory 3
In the case of the absolute method, the hole machining start position stored in the block is stored in the command position register R (step 8). next,
The contents of the next block _B2 are decoded (step 9), and if there is a change in the modal data, the stored information in the modal information storage area of the nonvolatile memory 3 is rewritten.

Then, the commanded movement amount of the block _B2 is added to the commanded position register R in the case of the incremental system, and the contents of the register R are replaced with the commanded position of the block _B2 in the case of the absolute system. In this embodiment, since an incremental method is used, the value is added to the register R as described above (step S10). The value of register R thus obtained indicates position _P2 in FIG. Therefore, the value of this register R is compared with the SZ position where the tool is stopped, which is indicated by the current value counter.In addition, in this example, drilling is performed in the Z-axis direction, so this comparison is performed only on the Z-axis. However, if the value of the register R is larger (in this example, since the movement is in the negative direction of the Z axis, if expressed as an absolute value, it will be the value of step S11 in Fig. 8).
In other words, since the distance between P ₁ and P ₂ shown in Figure 7A is smaller than the distance between P ₁ and SZ,
Read the decoding of the next block _B3 again (8th
(see figure). Then, if there is modal data, update it, add the command movement amount of the block _B3 to register R (the value of register R indicates the position of _P3 in Fig. 7A), and add the Z-axis value of register R. and the Z-axis value at the SZ position where the tool is stopped. In this case, as shown in Figure 7A, the distance between P ₁ and P ₃ is P ₁
-SZ distance, that is, the value of the tool stop position SZ is greater than the value of register R, so in this case, the _above Perform processing according to the stored modal data. and,
The processing of blocks B ₄ and below at position P ₃ and onwards changes to normal processing. Further, as shown in FIG. 7B, even when the hole machining is interrupted on the return path, the same processing as described for the interruption on the outward path shown in FIG. 7A is performed.

In the above embodiment, a specific sequence number (N7000 to N7999) is attached as a specific code to the machining start positioning block in discontinuous machining.
This is memorized every time the machining start positioning block is read, and when machining is interrupted during machining, the sequence number is searched and restart processing is performed, but the number of characters in the machining start positioning block is read out. By attaching a pointer and storing the pointer, when restarting the process after interruption, the process can be restarted from the read pointer.

Effects of the Invention As described above, in a numerical control method that performs discontinuous machining processing, when machining is interrupted and restarted during one machining process, the device automatically Since the restart position and processing are determined and carried out at the same time, there is no need for troublesome work associated with restarting, and processing efficiency can be increased.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a machining process suitable for employing the numerically controlled machining restart control device of the present invention, FIG. 2 is an explanatory diagram of drilling process, and FIG. 3 is an explanatory diagram showing the drawbacks of the conventional method. 4 are explanatory diagrams of the configuration of the present invention, FIG. 5 is a hardware configuration diagram of an apparatus according to an embodiment of the present invention, FIGS. 6 and 8 are flowcharts of an apparatus according to an embodiment of the present invention, FIG. 7 is an explanatory diagram of processing in the apparatus according to the embodiment of the present invention. 4...Manual data input device, 9...Position detector, W...Workpiece, _B1 to _B7 ...Block, _P1
~P ₇ ...Position, SZ...Interrupted tool stop position.

Claims (1)

[Claims] 1. A numerical control device that performs intermittent machining according to commands of an NC program, comprising a non-volatile memory that stores modal data in the program and a specific code attached to a machining start positioning block;
Start of restart machining by determining the machining start positioning block for the interrupted machining from the NC machining program based on the key input means for the machining restart command and the specific code stored in the non-volatile memory mentioned above when the machining restart command is input. a positioning block indexing means, a current value counter that stores the tool stop position,
Tool stop block detection that detects a tool stop block by comparing the tool end point position indicated by the block after the restart machining start positioning block indexed by the restart machining start positioning block indexing means with the value of the above current value counter. Machining is performed according to the modal data stored in the non-volatile memory to a tool end point position indicated by the tool stop block detected by the tool stop block detection means and the tool stop block detection means;
A numerically controlled machining restart control device characterized by comprising a control means for subsequently performing normal processing. 2. When controlled by the incremental method, the machining start position in the machining start positioning block is also stored in the non-volatile memory, and the tool stop block detection means stores the subsequent movement amount of the block at the memorized machining start position. A numerically controlled machining restart control device according to claim 1, which calculates the tool end point position of each block by sequentially adding the values. 3. The numerical control restart control device according to claim 1 or 2, wherein the specific code is a specific sequence number. 4. The numerically controlled machining restart control device according to claim 1 or 2, wherein the specific code is a pointer for displaying and reading out the number of characters from the beginning of the program.