JPS6215056A - Numerical control device for machine tool - Google Patents

Abstract

PURPOSE:To have efficient processing in a machining condition widened to possible max. limitation by comparing the restrained amount of depth feed for tool with the max. depth feed amount determined from the power of machine or the torque value and by using either of them which is the smallest to be fed out as the depth feed amount. CONSTITUTION:Into an input apparatus 1 are entered such data as output power of machine tool NL, work machining resistance KS, machining speed V and machining feed speed f. These serve for determination of a maximum depth feed amount t to be carried out at a calculator 2 on the basis of capacity of machine tool. The restrained depth feed amount tmax for the tool used currently is entered into another input apparatus 3 and stored in a memory 4. A comparator 5 compares the max. depth feed amount t calculated byte calculator 2 with the restrained depth feed amount tmax stored in said memory 4. Either of these values which is the smallest is emitted through an output device 6 as optimum amount of depth feed T, which serves for control of the machine tool. Accordingly efficient processing can be made in a machining condition which is widened to possible max. limitation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a numerical control device for a machine tool, and is useful when applied to determine the optimum cutting amount in machining with an NC machine tool.

[Conventional technology]

Conventionally, when machining a workpiece using an NC machine tool, the following methods were used: ■ Specify the depth of cut, ■ Specify the number of cuts and divide the entire machining allowance equally, or ■ Specify the number of cuts and use a formula. The company had decided to divide the company into unequal parts.

[Problem that the invention seeks to solve]

However, in the above-mentioned conventional technology, the depth of cut is determined regardless of the maximum capacity of the NC machine tool or the maximum capacity of the tool. Therefore, the depth of cut in this case was determined by human intuition and experience, and the capabilities of the machine and tools could not be fully utilized.

SUMMARY OF THE INVENTION In view of the above-mentioned prior art, it is an object of the present invention to provide a numerical control device for a machine tool that can perform machining with the maximum depth of cut that the machine or tool has, is efficient, and can shorten machining time.

[Means for solving problems]

The configuration of the present invention that achieves the above object is based on a numerical control device for a machine tool that determines the maximum amount of cut that a tool can make when machining a workpiece, and the amount of cut that is calculated from the power or torque value of the machine. The feature is that the smaller value is outputted as the depth of cut.

〔Example〕

Embodiments of the present invention will be described in detail below based on the drawings.

The figure is a block diagram showing an embodiment of the present invention. As shown in the figure, the input 51 includes the machine tool output Nt, which is the object to be controlled at this time, the cutting resistance KS of the workpiece, and the cutting speed V.
and the cutting feed speed f are supplied as input values. The calculator 2 calculates the mechanical efficiency of the machine based on the input value supplied to the input device 1. The value t determined by this calculation is the maximum depth of cut of the tool based on the capability of the machine tool.

The input device 3 contains the limit cutting depth l tm of the tool used at this time.
ax is provided as an input value. The storage device 4 stores the input values supplied to the input device 3. The comparator 5 compares the maximum depth of cut t calculated by the calculator 2 with the limit depth of cut 1 tmax stored in the storage device 4, and selects the smaller value through the output device 6 as the most appropriate value. Output as included IT,
This is used to control machine tools.

Therefore, according to the apparatus of this embodiment, in order to automatically determine the depth of cut in turning rough machining on a lathe, for example, the automatic gross system includes the output characteristics Ni of the machine tool, the cutting force Ks, the cutting speed V, and the cutting speed V. The feed speed f is registered, and the calculator 2 calculates the maximum depth of cut 1t from these values.

On the other hand, the limit depth of cut 1 tmax that the tool used in the machining can cut geometrically and mechanically is registered in the automatic pro system, and the values of these t and tmax are compared and the smaller ( If they are equal, the value of t) is selected and adopted as the optimal inclusion amount T.

Now, NL = 7.5 (Kw), Ks = 20
0 (11/mm”), ■=100 (m/am), h=
0.2 (1111/r6y) and η=0.8, the maximum cutting depth 11 is, on the other hand, if the limited cutting depth tmax=7 (m) at this time, tmaX<tl. Therefore, the optimal included IT in this case is 7 ms (==tmax).

Under the same conditions as above, ' 2 '' 0-3 (W&/r
6y), the maximum depth of cut t2 is 6II11
becomes.

That is, jmax>tz. Therefore, the optimal inclusion amount T in this case is 6gCI (=t2).

〔Effect of the invention〕

As specifically explained above in conjunction with the embodiments, according to the present invention, a workpiece can be machined under cutting conditions that are at their maximum limit according to the lower of the machine tool's ability or the tool's ability. , allows for efficient machining.

[Brief explanation of the drawing]

The figure is a block diagram showing an embodiment of the present invention. In the figure, 1.3 is the input device, 2 is a computing unit, 4 is a storage device, 5 is a comparison device.

Claims (1)

[Claims] In the numerical control device of a machine tool, the maximum depth of cut that a tool can cut when machining a workpiece is compared with the depth of cut calculated from the power or torque value of the machine, and the smaller of the two is selected. A numerical control device for machine tools characterized by outputting a value as a depth of cut.