JPS6364108A - Numerical controller having malfunction checking function - Google Patents

Abstract

PURPOSE:To check a malfunction and to perform the numerical control processing with a high reliability by comparing a temporary moving quantity at the time of a temporary execution and moving quantity at the time of an actual processing, and performing an alarm processing when a difference is a constant quantity or above. CONSTITUTION:A temporary is performed by by command value storage means 1 for a numerical control, a command executing means 2, etc., and the temporary moving quantity for a constant time is stored into a temporary moving quantity storage means 3. The moving quantity at the time of the actual processing and the storage contents corresponding to the means 3 are compared by a comparing means 4,and when the difference comes to be a prescribed value or above, the processing by an alarm processing means 5 is performed. By giving the malfunction checking function, the reliability of the numerical control processing is improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a numerical control device having a malfunction check function, and in particular, to a numerical control device that generates an alarm when the difference between a temporary movement amount and an actual movement amount exceeds a certain level. The present invention relates to a numerical control device having a malfunction check function.

[Conventional technology]

When machining very expensive workpieces using a numerically controlled machine tool, unlike mass production machining of inexpensive workpieces, it is necessary to strictly check the malfunction of the numerical control device. For this reason, a system has conventionally been adopted in which two identical numerical control devices are used and an alarm is generated when the difference in the amount of movement between the devices exceeds a certain value. Further, even if two numerical control devices are not completely used, devices have been used that improve the reliability of processing by duplicating some of their functions.

[Problem that the invention seeks to solve]

However, these dual systems have the problem that the hardware is doubled, making them very expensive, and that the processing speed is slow because processing is performed while checking each other's signals.

The purpose of the present invention is to solve the above problems, perform temporary machining before actual machining, store the data of the temporary machining in memory, and set an alarm when the difference between the nominal movement amount and the actual movement amount exceeds a certain level. An object of the present invention is to provide a numerical control device having a malfunction check function.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention provides a numerical control device having a malfunction check function that automatically checks malfunctions during operation, and includes command value storage means for storing command values; A command execution means to be executed, a provisional movement amount storage means for storing a provisional amount of movement at fixed time intervals during temporary execution, and a comparison between the actual movement amount and the provisional amount of movement stored in the provisional amount of movement storage means during actual machining. and an alarm processing means, the malfunction check function is characterized in that the alarm processing means carries out alarm processing when the difference between the hypothetical movement amount and the actual movement amount exceeds a certain level. We adopted a numerical control device with

[Effect]

At the time of temporary execution, the workpiece was not processed, and the operation was performed using f! The confirmed tentative amount of motion is stored in the tentative amount of motion storage means.

During actual machining, machining is performed while constantly comparing the confirmed nominal movement amount with the actual movement amount, and when the difference between them exceeds a certain level, an alarm is generated.

〔Example〕

An embodiment of the present invention will be described below based on the drawings.

FIG. 1 shows a block diagram of an embodiment of the present invention.

Reference numeral 1 denotes a command value storage means, which stores the program of the numerical control device. Reference numeral 2 denotes a command execution means, which reads out the program and distributes pulses.

Reference numeral 3 denotes a provisional accumulated motion amount storage means, which virtually performs pulse distribution without first moving the machine, and stores the amount of movement at fixed time intervals. This time is about 10 to 20 msec. 4 is a comparison means, and the provisional product v during actual machining
The tentative amount of movement stored in the first amount storage means 3 is compared with the actual amount of movement. Then, it is checked whether this difference is within a certain value, and if it exceeds the certain value, an alarm signal is sent to the alarm processing means. Reference numeral 5 denotes an alarm processing means, which performs processing such as stopping processing and displaying an alarm.

FIG. 2 shows a block diagram of hardware for implementing the present invention. In the figure, 11 is a CPU, which performs overall control. Reference numeral 12 denotes a ROM in which a control '+B program for the numerical control device is stored. 13 is a RAM, which consists of volatile RAM and nonvolatile RAM. Data that should be stored even after the power is turned off, such as parameters, is stored in nonvolatile RAM. 14 is an input device, and a paper tape reader or the like is used. 15 is a paper tape on which a processing program is punched. 16 is a display device, and a CRT, liquid crystal display, etc. are used. A keyboard 17 is used to input various data. 18
is a programmable machine controller (PMC) that receives data and controls the machine. Reference numeral 19 denotes a machine operation panel, which is used by an operator to operate the machine. 20 is a memory interface, which is an interface with an external memory device. Reference numeral 21 denotes an external memory, and a floppy disk, case note memory, etc. are used. 22 is a control circuit for controlling the servo motor. A servo amplifier 23 receives a signal from the control circuit 22 and drives the servo motor. Reference numeral 24 denotes a servo motor, which contains devices such as a pulse coder for velocity feedback and position feedback, and drives a movable part of the machine (not shown). In the figure, the control circuit 22, servo amplifier 23, and servo motor 24 are shown for only one axis, but normally they are configured for two to S axes, and the second and subsequent axes are omitted.

Next, the operation of this embodiment will be described based on a flowchart. FIG. 3 shows a flowchart of this embodiment. Each step is designated by a symbol such as Sl, 32, etc.

It is assumed that the processed tape 15 punched into the tape is read by the tape reader 14 and the processed program is stored in the RAM 13.

Step 1 (Sl) At first, the machine is not moved, but is temporarily operated to perform pulse distribution. That is, a processing simulation is performed, pulse distribution is performed at fixed time intervals, and this is used to temporarily move the machine jlsMP (
output as t).

Step 2 (32) This output is sequentially stored in the external memory 21.

Note that the data is stored in groups for each distributed block of the Kani program in order to be read out at high speed during actual processing.

Step 3 (33) Next, the workpiece is set and actual machining is performed. At this time, the temporary movement amount for each block is read from the external memory 21 and stored in the RAM 13. Then, the actual machine movement amount RMP is calculated at the same fixed time intervals as in the simulation.
Find (t).

Step 4 (S4) It is determined whether the absolute value of the difference between the actual movement amount RMP (t) of this machine and the temporary movement amount SMP (t) during simulation is less than or equal to a certain value. When it is below a certain value,
This is normal operation and to continue machining, step 3 (S
Return to 3). This constant value is stored in RAM13 as a parameter.
are stored and changed according to each condition. If it is not below a certain value, it is assumed that some abnormality has occurred and the process goes to step 5 (35).

Step 5 (S5) Assuming that an abnormality has occurred, pulse distribution is stopped and an alarm message is displayed on the display device 16.

In the above explanation, the temporary movement amount was calculated by simulation without moving the machine, but the temporary movement amount can be calculated by running the machine idly without setting a workpiece, or by operating the machine without a tool attached. You can also ask for In this case, it takes a long time to determine the temporary movement amount, but confirmation becomes more reliable.

Furthermore, internal state values other than the amount of movement, such as offset i, speed, etc., can also be compared.

In this way, expensive workpieces can be machined in more reliable machining conditions.

〔Effect of the invention〕

As explained above, in the present invention, the provisional movement amount is temporarily stored and the processing is performed while comparing the provisional movement amount and the actual movement amount during actual machining, so that more reliable machining can be performed. can.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the invention, FIG. 2 is a hardware configuration diagram of an embodiment of the invention, and FIG. 3 is a flowchart of an embodiment of the invention. 1 --- Command value storage means 2 --- Command execution means 3 --- Temporary movement amount storage means 4 --- Comparison means 5 --- Alarm processing Means 11...CPU 13---RAM 21----External memory Patent applicant Fanuc Co., Ltd. agent Patent attorney Takeshi Hattori Figure 1 Figure 2 Figure 3

Claims (3)

[Claims] (1) In a numerical control device having a malfunction check function that automatically checks for malfunctions during operation, a command value storage means for storing command values, a command execution means for reading and executing the command values, and a temporary execution means. a temporary movement amount storage means for storing a temporary movement amount at regular intervals; a comparison means for comparing the actual movement amount with the temporary movement amount stored in the temporary movement amount storage means during actual processing; and an alarm processing means. 1. A numerical control device having a malfunction check function, characterized in that the alarm processing means performs alarm processing when the difference between the tentative movement amount and the actual movement amount exceeds a certain value. (2) The numerical control device having a malfunction check function according to claim 1, wherein the temporary execution is a simulation in which only pulse distribution within the numerical control device is performed. (3) A numerical control device having a malfunction check function according to claim 1, wherein the temporary execution is temporary cutting of a workpiece.