JPH08257873A - Control device for nc machine tool - Google Patents

Abstract

PURPOSE: To automatically change a quick feed speed in the case of automatic or MDI operation, and to easily change the quick feed speed by a manual switch of simple constitution in the case of manual operation, so as to obtain a feed speed suited for linear cutting of planing work or the like. CONSTITUTION: In the case of automatic operation and MDI operation, a feed shaft motor 22 is controlled by a feed shaft motor drive control part 21 based on a speed command in a program, to automatically change a quick feed speed. In the case of manual operation, a planer work shaft 14b is selected by a manual feed shaft selective switch 14, to set an arbitrary feed speed while watching a planer cutting speed scale by a manual/planer feed speed switch 13, and a feed direction is switched by a cutting feed direction changeover switch 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for obtaining a feed rate suitable for linear cutting such as planing in an NC machine tool.

[0002]

2. Description of the Related Art In an NC machine tool whose cutting speed is increased by rotating a work or a cutting tool, when performing linear cutting such as planing, the feeding speed can be selected from cutting feed and fast feed. Since the feed is slow and the machining efficiency is poor, it is usually performed by fast feed. In the conventional NC machine tool, the rapid feed speed is set to a constant value, and therefore when changing the cutting speed, it is necessary to manually set the rapid feed speed with the rapid feed override switch.

[0003]

However, when the override function is activated, the rapid feed speed of other normal machining is also slowed down and the overall machining efficiency is reduced. Therefore, the operator has the trouble of switching overriding each time depending on the processing conditions. In addition, if one switch is used for both the rapid feed override function and the cutting feed override function, the number of speed conversion steps increases, which makes it difficult to view the speed display.

[0004] Therefore, the problems of the present invention are automatic and MDI.
In the case of operation, the rapid traverse speed can be changed automatically, and in the case of manual operation, the rapid traverse speed can be easily changed with a manual switch with a simple configuration, which is suitable for linear cutting such as planing. An object of the present invention is to provide a controller for an NC machine tool that can obtain

[0005]

In order to solve the above-mentioned problems, the control device of the present invention is, in an NC machine tool, a feed input corresponding to a specific positioning command during program automatic operation and MDI operation. A program analysis unit capable of instructing a function generating unit to determine a rapid feed speed based on a speed command, and a feed speed change set amount selection unit that selects to change the rapid feed speed by a cutting feed speed change set amount in response to the specific control command. And a fast-forward speed setting means capable of setting a fast-forward speed by a manual switch during manual operation.

[0006]

According to the above construction, in the automatic and MDI operation, the rapid feed speed is automatically changed by the speed command in the machining program. In the case of manual operation, the fast-forward speed is changed to the optimum value by operating the manual switch.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 and 2 illustrate a portal machining center as an NC machine tool. A spindle ram 2 for holding a spindle (not shown) is movably supported on a machine frame 1 of the machining center in the Y and Z directions, and a planar attachment 3 is attached to the lower end of the spindle ram 2. The attachment 3 is constructed by attaching a cutting tool 6 to a tool rest 4 via a holder 5. Machine frame 1 facing the spindle ram 2
A table 7 is placed on the table so as to be movable in the X direction.

FIG. 3 shows the construction of the operation panel 8 and the numerical controller 9 of the machining center. The operation panel 8 includes a keyboard 10, a rapid feed override switch 11, a cutting feed override switch 12, a manual / planar feed speed switch 13, a manual feed axis selection switch 14, a cutting feed direction changeover switch 15, and a cutting feed stop switch 1.
6 are provided. The manual / planar feed speed switch 13 is provided with a planar cutting speed scale 13b on the outer periphery of the manual cutting speed scale 13a. The manual feed shaft selection switch 14 is provided with a planar machining shaft 14b in addition to the existing X, Y, and Z shafts 14a. The switches 13 to 16 and the like constitute a manual feed speed changing means.

When the planer machining is performed automatically by a program, the numerical controller 9 functions as an automatic feed rate changing means, and the program read from the machining program storage section 18 is analyzed by the program analysis section 19.
When the command at this time is a positioning command of G00 or an interpolation command of G01, etc., since it is a normal cutting process, both the rapid feed override and the cutting feed override are enabled and individually function. Then, the data of the rapid feed override storage unit 24 or the cutting feed override storage unit 25 is multiplied by the output from the function generation unit 20 and input to the feed shaft motor drive control unit 21, and the control unit 21 controls the feed shaft motor 22. And the rotation speed of the encoder 23
Detected in.

When the command of the program is a positioning command G □□ (specific numerical value) other than the above G00, the program analysis unit 19 analyzes the F command in the program to obtain the fast-forward speed, and the function generation unit 20. Is output to. The function generator 20 outputs a function of the fast-forward speed corresponding to the F command. At this time, for the override, the data in the cutting feed override storage unit 25 is selected as the override value by the override selecting unit 26, the output of the function generating unit 20 is multiplied by the cutting feed override, and the result is output to the feed shaft motor drive control unit 21. . In the case of MDI operation, the M input by the keyboard 10
Based on the DI input information, the feed shaft motor 22 is controlled as in the case of the program automatic operation.

When the planar machining is performed manually,
First, press the manual feed axis selection switch 14
4b is selected, and the result is confirmed by the manual feed shaft selection unit 29. Next, the manual / planar feed speed switch 13 is used to set an arbitrary feed speed while observing the planar cutting speed scale 3b, and the set value is stored in the manual feed speed storage unit 27. Then, the feed direction is switched by the plus key or the minus key of the cutting feed direction changeover switch 15, and the result is confirmed by the cutting feed direction selection unit 28. Then, the axis feed command sending section 21 calculates the axis feed speed during planar machining, and the speed instruction in the selected cutting feed direction is sent to the feed axis motor drive control section 21 via the function generating section 20. As a result, the planar machining axis is driven at the command feed speed, and the planer machining of the workpiece by the planar attachment 3 is performed. Positioning to the planer machining position, retreat after machining, etc. is set by the rapid feed override 11 to the normal override value stored in advance in the NC device by setting the manual feed axis selection switch 14 to the desired feed axis. The fast-forward override storage unit 24 can move the override stored at the multiplied fast-forward speed. As a result, the optimum planar machining speed and the optimum rapid feed speed can be used without frequently changing the override amount each time.

The present invention is not limited to the above-described embodiment. For example, the switching and stopping of the direction of the cutting feed is not performed by the switches 15 and 16, but manually fed by a general NC machine tool. For example, by using the time direction specification method,
It is also possible to change and embody the configuration of each part as appropriate without departing from the spirit of the present invention.

[0013]

As described in detail above, according to the present invention,
In the case of automatic and MDI operation, the rapid traverse speed can be automatically changed, and in the case of manual operation, the rapid traverse speed can be easily changed with a manual switch with a simple structure, which is suitable for linear cutting such as planing. It has an excellent effect that a high feed rate can be obtained.

[Brief description of drawings]

FIG. 1 is a front view of a portal machining center showing an embodiment of the present invention.

FIG. 2 is a side view of the machining center.

FIG. 3 is a block diagram showing a control device of the machining center.

[Explanation of symbols]

2 ・ ・ Spindle ram, 3 ・ ・ Planar attachment, 8 ・
・ Operation panel, 9 ・ ・ Numerical control device, 10 ・ ・ Keyboard,
13 ... Manual / planar feed speed switch, 14 ... Manual feed axis selection switch, 21 ... Feed axis motor drive control section, 29 ... Manual feed axis selection section, 30 ... Axis feed command sending section

Claims (1)

[Claims] 1. In a NC machine tool, a program analysis unit that outputs a fast-forward speed to a function generation unit based on a feed speed command input corresponding to a specific positioning command during program automatic operation and MDI operation, and the specification. There is a feed rate change set amount selection unit that selects to change the fast feed speed corresponding to the positioning command of the cutting feed rate change set amount, and a rapid feed speed setting means that can set the rapid feed speed with a manual switch during manual operation. A control device for an NC machine tool, wherein a rapid feed speed can be set by a control command in the automatic operation and the MDI operation at the time of the specific positioning command and by a manual switch in the manual operation.