JPH01320505A - Numeric value control system - Google Patents

Abstract

PURPOSE:To prevent an interpolation stopping time from being generated by automatically adjusting interpolation speed so as not to set the amount of data of execution format stored in a memory at a value less than a prescribed value. CONSTITUTION:An execution data block number adding part 9 adds '1' on the number of blocks of the data SC of execution format from an execution data generating part 3, and stores it in the memory 8B. Meanwhile, an execution data subtracting part 10 subtracts '1' from the number of blocks of the execution data stored in the memory 8B. And an interpolation speed command generating part 4 finds an interpolation speed command by the data SM of execution format from the subtracting part 10, and outputs it to an interpolation speed command change control part 11. The control part 11 reads out the number SK of blocks of the execution data stored in the memory 8B, and compares the number with a reference value. When it is less than the reference value, i.e. when the stopping time of an interpolating time is generated, the interpolation speed is adjusted automatically.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a numerical control method for controlling a drive section of a machine using a nitrogram.

(Prior Art) FIG. 3 is a block diagram showing an example of a numerical control (hereinafter referred to as NC) device that realizes a conventional numerical control method. input device such as a reader i h) A program import unit 2 that reads the program S block by block from the input device such as a reader, and a program import unit 2 that reads one block of data SB from the program read unit 2, taking into account, for example, origin offset data and tool offset data. The data is converted into executable data SC consisting of the target position, spindle rotation speed, etc., and stored in an empty buffer among buffers 1 to N in the memory 8^, and the read command SG for the next block is sent to the program reading section. 1. Furthermore, an interpolation speed command generation unit 4 that generates an interpolation speed command from the oldest execution format data SD among the execution format data SC stored in buffers 1 to N in the memory 8^, and this interpolation distance A function generation control section 5 that generates a function using executable data SE including an interpolation speed command from the command generation section 4, and a drive control section 6 that controls the drive section 7 according to the function SF from the function generation control section 5. It is made up of.

(Problems to be Solved by the Invention) In the above-mentioned conventional numerical control method using an NC device, when the cutting feed rate is large even though the axis movement amount of one block is small, as in the case of a mold machining program, for example, As shown in FIG. 5, the interpolation processing time tb for one block is shorter than the preprocessing time t8 for l block for reading one block and converting it into executable format data, and there is no interpolation stop time between blocks. tc is generated. Furthermore, if the speed of communicating the program in communication is slow, the preprocessing time for one block becomes longer than the interpolation processing time for one block, and interpolation stop time occurs as described above. When this interpolation stop occurs, the cutting operation becomes intermittent,
Cutter marks were left on the machined surface, deteriorating machining accuracy. In order to prevent this interpolation stop time from occurring, the operator must use a feed rate override switch to lower the cutting feed rate, which is time consuming.

The present invention was made in view of the above-mentioned circumstances, and an object of the present invention is to provide a numerical control method that can automatically adjust the interpolation distance and prevent the occurrence of interpolation stop time. It's about doing.

(Means for Solving the Problems) The present invention sequentially reads blocks of consecutive interpolation commands on a Canadian program to generate data in an executable format, and sequentially stores the generated data in an executable format in a storage means. The present invention relates to a numerical control method for controlling a drive means by sequentially reading stored executable data from the storage means and performing interpolation. This is achieved by automatically adjusting the interpolation speed so that the number of executable data does not fall below a predetermined value.

(Function) The numerical control method of the present invention automatically adjusts the interpolation distance when there is a risk that the machine will stop because data reading in the executable format for interpolation is faster than data generation in the executable format.
This prevents the machine from stopping and enables smooth machining.

(Embodiment) FIG. 1 is a block diagram showing an example of an NC device that implements the numerical control method of the present invention, corresponding to FIG. 3, and the same components are given the same reference numerals and the description thereof will be omitted. This NC device stores the data SC in the executable format from the execution data generation unit 3 in the original format SL in the buffers 1 to N in the memory 8^, and also stores the data in the executable format that has not yet been executed in the blocks. (hereinafter referred to as the number of execution data blocks) and stores the execution data block number Sl in the memory 8B, and the number of execution data blocks is stored in buffers 1 to N in the memory 8A. The oldest executable format data SD among the executable format data SL is output to the interpolation far command generation unit 4 in its original format SM, and the number of execution data blocks stored in the memory 8B is counted down, and the execution data is The execution data block number subtraction unit 10 stores the block number SJ in the memory 8B again, and the execution format data SE including the interpolation farness command from the interpolation speed command generation unit 4 is interpolated based on the counted down execution data block number S. An interpolation farness command change control section 11 is newly provided that changes only the farness command, generates execution form data SN, and outputs it to the function generation control section 5.

In such a configuration, an example of its operation will be explained with reference to the flowchart of FIG.

Then, the execution data generation section 3 converts one block of data S into execution format data SC and outputs it to the execution data block number adding section 9. Furthermore, the execution data block number adding unit 9 converts the data SC in the execution format into the data SC in the original format S.
At the same time, "1" is added to the number of execution data blocks and stored in the memory 8B. In this case, since it is still the first block, the number of execution data blocks is "1". The above-described operation is repeated until there is no empty buffer in the memory 8A or until the program ends, and the number of execution data blocks is incremented by "1" each time data in an execution format is generated.

On the other hand, in the execution data block number subtraction unit lO, the memory 8A
The data SD in the oldest execution format is read out from , and is output to the interpolation farness command generation unit 4 in the same format SM.
"1" is subtracted from the number of execution data blocks stored in the memory 8B (step si). The interpolation distance command generation unit 4 obtains the interpolation speed command using the execution format data SM (
In step S2), the data is output to the interpolation farness command change control unit 11 together with data in other execution formats. The interpolation farness command change control unit 11 reads out the number of execution data blocks S stored in the memory 8B and compares the value with the reference value (step S3), when the number of execution data blocks S is greater than the reference value. If it is large, that is, if there is extra data in the execution format and the machine will not stop due to the interpolation stop time that occurs while waiting for the data in the execution format even if the cutting speed is not reduced, use the interpolation distance command using the program command. If the number of execution data blocks S is smaller than the reference value, it is 5, that is, there is less data in the execution format, so if machining is continued at the cutting speed of the program command, it will be necessary to wait for the data in the execution format. If the machine is stopped due to the interpolation stop time that occurs, the interpolation speed command based on the program command is changed to reduce the cutting speed (step S4), and the function generation control unit 5 outputs the data as data SN along with other execution format data. Output to (
Step 55). Then, the function generation control section 5 generates a function SF based on the executable data SN, and the drive control section 6 controls the drive section 7 according to this function SF. The above-described operations are repeated as long as there is executable data in memory 88.

If the method of the present invention is applied to mold machining where the amount of movement per block is small and the cutting feed rate is large, as explained in Fig. 5, the number of data in the executable format stored in the memory will decrease, as shown in Fig. 4. As shown in FIG. 5, the interpolation distance is automatically reduced, and the preprocessing time t2 and the interpolation processing time 1 b+ become equal, so that the interpolation stop time te as shown in FIG. 5 does not occur.

(Effects of the Invention) As described above, according to the numerical control method of the present invention, the interpolation distance is automatically adjusted so that the interpolation stop time does not occur, so the burden on the operator can be reduced, and the cutting operation is not interrupted. This makes it possible to improve machining accuracy.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of an NC device that implements the numerical control method of the present invention, FIG. 2 is a flowchart explaining an example of its operation, and FIG. 3 is an example of an NC device that implements the conventional numerical control method. FIG. 4 is a diagram showing the relationship between interpolation farness and time according to the method of the present invention, and FIG. 5 is a diagram showing the relationship between interpolation speed and time according to the conventional method. 1...Manpower equipment, 2...Program reading section, 3...
- Execution data generation unit, 4... Interpolation far command generation unit, 5
... Function generation control section, 6... Drive control section, 7...
Drive unit, 8^, 8B...Memory, 9...Execution data block number addition unit, 10...Execution data block number wave calculation unit, 11...Interpolation far distance command change control unit. Applicant's agent Yu Yasugata 3rd cause

Claims (1)

[Claims] 1. Sequentially read blocks of continuous interpolation commands on the machining program to generate executable data, sequentially store the generated executable data in a storage means, and store the stored executable data in the storage means In a numerical control method that controls a drive means by sequentially reading data and performing interpolation, the speed of the interpolation is automatically controlled so that the number of data in the execution format stored in the storage means does not become less than a predetermined value. Numerical control method characterized by adjusting to.