JPH0741516B2 - NC device - Google Patents

Description

TECHNICAL FIELD The present invention automatically determines machining conditions such as the rotational speed of a spindle and the feed rate of a tool based on input data such as the shape and material of a workpiece or tool and machining accuracy. The present invention relates to an NC device having a setting function.

2. Description of the Related Art Conventionally, an NC device having an interactive program creation function of a machine tool such as a lathe, a grinder, a machining center, etc. has respective storage elements of a first RAM to a fourth RAM as shown in FIG. Shape data, material, tool data, machined surface and machining method, required accuracy, etc. stored and stored, and standard machining conditions obtained from the input data and stored in the second RAM, that is, the peripheral speed of the workpiece. The machining conditions are automatically calculated by the automatic condition setting circuit based on the tool feed amount per 1 spindle rotation, etc., stored in the 3rd RAM, converted to the NC program, and then stored in the 4th RAM for each axis. It is designed to control.

Problems to be Solved by the Invention The automatically set machining conditions described in the prior art do not always provide satisfactory machining results according to the conditions,
Corrections are often made at the work site. In particular, in the case of grinding that has many uncertainties in the set conditions, there is a problem in that an extra setup time is required every time the number of corrections increases and the work content changes, which is complicated.

The present invention has been made in view of such problems of the conventional technique, and an object of the present invention is to perform an automatic machining with a function capable of automatically feeding back modified machining conditions from the next time onward. The purpose is to provide an NC device with a condition setting function.

Means for Solving the Problems In order to achieve the above object, the NC device according to the present invention is
A means for calculating the corrected ratio when the automatically set machining conditions are corrected and storing it as a coefficient, a data table in which the rigidity of the workpiece or tool, the material, the required machining accuracy of the workpiece, etc. are ranked, and the correction When the combination of the respective ranks of the data table corresponding to the processed condition is read and replaced with the coefficient, and the combination of the corresponding ranks of the input values after the next time is the same, the coefficient data table is included in the processing condition. And a means for automatically correcting by multiplying by the corresponding coefficient of.

Function When the automatically set machining condition data is displayed on the CRT and asked if there are any corrections, and if corrections are made at the work site to approach the ideal machining conditions, this correction rate is stored as a coefficient, For example, the coefficient data table in which the corrected machining conditions correspond to, for example, the rigidity of the work, the material of the work, the required accuracy of the work, and the like, is read and the coefficient data table is replaced with the coefficient is stored, and the next time, When the combination of the corresponding ranks of the input values becomes the same, the corresponding coefficient in the coefficient data table is automatically multiplied to correct the machining condition and create the NC program.

Example An example will be described with reference to FIGS. 1 to 4.

In the NC cylindrical grinder, the table 2 is movably mounted on the sliding surface in the Z-axis direction cut on the bed 1, and the headstock 3 and tailstock 4 can be moved to the mounting positions on the table 2. It is placed in. Then, the work W is supported by both centers between the headstock 3 and the tailstock 4, and the work W is rotated by the spindle motor 5.

On the other hand, a guide in the X-axis direction is provided on the rear side of the bed, and the grindstone 7 is movably mounted on this guide, and the grindstone is rotatably supported on the grindstone 7 at the left end of the grindstone. 8 is attached. The grindstone 8 is rotated by the grindstone motor 9, and the grindstone base 7 is moved and positioned by the grindstone motor 11.

A keyboard for input is provided in the NC device that controls the grindstone motor 11 and the spindle motor 5 shown in the block diagram of FIG.
12, I / O interface 13, 1st RAM14 are provided, 1st R
The AM14 includes a work shape data storage unit, a work material storage unit, a tool data storage unit, a machining surface / machining method storage unit, a work required accuracy storage unit, and the like. Furthermore, the peripheral speed of the workpiece (spindle) set by standard machining conditions, that is, the rigidity of the workpiece calculated from the workpiece shape and the type of tool,
2nd RAM1 that stores the cutting depth of the tool per spindle rotation
5, Automatic machining condition setting unit 16 that automatically sets the machining conditions by calculating the spindle speed from the workpiece diameter and peripheral speed, and the tool feed speed from the cutting amount per spindle revolution, etc. 3rd RAM17 to store the processing conditions, CRT18 to display the automatically set processing conditions on the screen, depending on the automatically set processing conditions
A fourth RAM 19 for creating and storing an NC program and an axis control circuit 21 for outputting a signal for controlling the drive unit 22 are provided. The above is no different from the contents of the conventional NC device with automatic machining condition setting function.

Next, the part a surrounded by the virtual line according to the present invention will be described. The fifth RAM 23 is a portion for memorizing the corrected machining conditions corrected by the operator when the operator sees the machining conditions displayed on the screen of the CRT 18 and stores the corrected machining conditions. Is a circuit for calculating a correction coefficient by comparing. As shown in FIG. 2, the rank-divided data table 25 is a work rigidity data table in which work rigidity values are ranked into A _{1 to} An within a certain setting range width, and the work material below the work rigidity data table is difficult to process. The work material data table is ranked according to the degree of B _{1 to} Bn, and the required machining accuracy data table is ranked below C _{1 to} Cn within a certain setting range width. It is configured. The coefficient data table 26 is constructed by assembling these three data tables into a hierarchical structure as shown in FIG. 3, so that, for example, when the symbol is D1, a combination of A1, B1, C1 and when it is D8 is A2, B2. , C2, and D1 to Dn are replaced with the coefficient (change ratio) calculated each time the processing conditions are corrected. The automatic correction circuit 27 is a circuit that corrects the automatically set machining conditions by multiplying them by a coefficient when the combination of corresponding ranks of the input values is the same after the next time.

Next, the operation of this embodiment will be described in the order of the flowchart of FIG.

In step S1, the input work shape data, work material, tool data, required accuracy, etc. are read and the first RAM is read.
The data is stored in each of 14 storage units. In step S2, the basic standard machining data such as the work peripheral speed calculated from the input data, the type of the tool, the peripheral speed of the work, and the cutting depth of the tool per revolution are set. The processed data is stored in the second RAM 15. Next, in step S4, the machining surface and machining method are read from the first RAM 14, and in step S5, the rotation speed (rpm) of the workpiece (spindle) is calculated from the workpiece shape and standard machining data,
Further, in step S6, the cutting speed (mm / min) is calculated from the cutting amount of the tool per one rotation. Then step S7
In, display the processing condition data on the screen of CRT18,
In step S8, the CRT screen is queried as to whether there is any modification. If the operator sees this and wants to make a correction in order to bring it closer to the ideal, the answer is NO, and in step S9, the worker executes (inputs) the modification of the processing conditions. Next, in step S10, the modification rate is calculated by comparing the machining conditions displayed on the CRT 18 with the modified machining conditions in the correction coefficient calculation circuit 24, and the modification rate is stored as a coefficient in step S11.

Next, in step S12, the rigidity of the work calculated from the shape data and the material of the work previously input by another means is read out, and in step S13, the rigidity of the read work corresponds to the rank of the corresponding data table 25. Read another symbol. Next, in step S14, the material of the work is read, and the symbol for each rank of the work material rank classification data table 25 corresponding to this is read, and in step S15
At, the required accuracy is read, and the rank-specific symbols of the required accuracy ranked data table 25 corresponding thereto are read.
Next, in step S16, the corresponding combination symbol in the data table read out is read out and replaced with the coefficient (change ratio) and stored. In step S17, the processing conditions based on the input data that will be the same combination from the next time onward are multiplied by the corresponding coefficient and output, and in step S18 an NC program is created and stored.

Further, in step S8, if there is no rework, the determination result is YES, the NC program is created according to the machining conditions displayed on the CRT, and the NC program is stored.

EFFECTS OF THE INVENTION Since the present invention is configured as described above, it has the following effects.

When the machining conditions automatically set by NC are modified, the modification ratio (coefficient) for the set machining conditions is calculated and stored,
The coefficient data table in which the combination of each rank of the data table in which the rigidity of the work or tool and the material, the required machining accuracy of the work, and the required machining accuracy of the work are respectively replaced with the coefficient is provided, When the combinations are the same, the processing conditions are automatically corrected by multiplying the corresponding coefficients, so that the ideal processing conditions can be automatically approximated regardless of the degree of skill of the operator.

[Brief description of drawings]

FIG. 1 is a plan view of a cylindrical grinding machine according to this embodiment in which a block diagram of an NC device is also shown, FIGS. 2 and 3 are explanatory views of a data table and a coefficient data table, and FIG. 4 is this embodiment. FIG. 5 is a flow chart for explaining the operation of the example, and FIG. 5 is a plan view of a cylindrical grinder with a block diagram of a conventional NC device with a function for automatically setting machining conditions. 24 …… Correction coefficient calculation circuit 25 …… Ranked data table 26 …… Coefficient data table 27 …… Automatic correction circuit

Claims (1)

[Claims] 1. An NC device having a function of automatically setting machining conditions such as a rotational speed of a spindle, a cutting or feeding speed,
When the automatically set machining conditions are corrected, a means for calculating the corrected ratio and storing it as a coefficient, a data table in which the rigidity of the work or tool, the material, the required machining accuracy of the work, etc. are respectively ranked, The coefficient data table in which the respective rank combinations of the data table corresponding to the modified machining conditions are read and replaced with the coefficients and the combination of the corresponding ranks of the respective input values from the next time onwards are the same An NC device comprising means for automatically correcting by multiplying a corresponding coefficient in a table.