WO2001075537A1

WO2001075537A1 - Numerical control device

Info

Publication number: WO2001075537A1
Application number: PCT/JP2000/002122
Authority: WO
Inventors: Shunro Ono; Daisuke Fujino; Kiyoshi Kuchiki
Original assignee: Mitsubishi Denki Kabushiki Kaisha
Priority date: 2000-03-31
Filing date: 2000-03-31
Publication date: 2001-10-11
Also published as: TW449526B

Abstract

A numerical control device which controls an NC machine tool having a rotating mechanism in which a table (2) turns on an axis (5) crossing perpendicular to the axial direction of a spindle (4), wherein the spindle (4)-to-table (2) interference areas (1, 7) are calculated from the rotating angle of the table (2) for each interpolation processing and it is checked in real time whether or not the spindle (4) interferes with the table (2) after movement so as to prevent tool systems (4, 6, 9) from interferring with the table (2).

Description

Description Numerical controller Technical field

The present invention relates to a numerical controller (hereinafter, referred to as an NC controller) for controlling a numerical control machine (hereinafter, referred to as an NC machine tool) having a rotating mechanism for rotating a table. This is for checking the interference between the table and the spindle. Background art

In an NC machine tool controlled by an NC device, tools, turrets, loaders, measuring devices, etc., operate simultaneously based on NC information from machining programs, etc., so that interference between operating parts and interference between operating parts and stationary parts occur. It is important to check for interference to avoid interference. As a conventional NC machine tool interference check device, such as a lathe, where the operating range of the tool is limited to a two-dimensional space, the shape of the tool, tool post, chuck, work, etc. is defined in a two-dimensional space In some cases, interference between defined shapes is checked in a two-dimensional space. For tools whose operating range extends over a three-dimensional space, such as a machining center, the shape of the workpiece and the mounting jig are defined on the χ-γ plane, and their thickness in the Z direction is defined. In some cases, the interference between the Z-coordinate value of the tool edge and the defined shape data is effectively checked in a two-dimensional space.

The shape data for checking these interferences is usually set as a fixed area by parameters or the like.

The table is fixed on a normal NC machine tool. 涉 The area does not change, and once the interference area is set, there is no need to set it again.

On the other hand, in the case of an NC machine tool having a table rotating mechanism as shown in Fig. 5, the interference area changes during machining, so that it was difficult or impossible to set the interference area.

Next, the reason will be described with reference to FIGS.

That is, FIG. 5 is a perspective view showing a 5-axis NC machine having a table rotating mechanism. The NC machine has the following structure and operates. That is, the bed 10 and the X-axis table 11 provided on the bed 10 so as to be movable in the X direction, and the Y-axis column 12 provided on the X-axis table 11 so as to be movable in the Y direction. And a Z-axis slider 13 provided on the Y-axis column 12 so as to be movable in the Z direction.The Z-axis slider 13 has a main shaft 4 mounted thereon, and is mounted on the main shaft 4. The workpiece is machined by rotating tool 16 at high speed.

In addition, the bed 10 rotates in a cradle shape around an axis perpendicular to the main axis (Z axis) direction and parallel to the X axis or Y axis (axis 5 parallel to the X axis in this example). A tilt table 2 is provided. On the tilt table 2, an opening table 15 having an axis 14 perpendicular to the table surface of the tilt table 2 as a rotation axis is provided. Axis 5 is generally called A axis, and axis 14 is generally called C 4.

The X-axis table 11, the Y-axis column 12, the Z-axis slider 13, the tilt table 2, and the row table 15 are not shown. Driven by axis servo motor, Z axis servo motor, A axis servo motor and C axis servo motor.

Each of the above servomotors is driven and controlled by an NC controller, and X, Y,

Move the spindle 4 position to any coordinate value of Ζ, and tilt table 2, —The desired processing is performed by arbitrarily controlling the posture of the work placed on the mouthpiece table 15 by rotating the mouthpiece table 15. An NC machine tool having a table rotating mechanism has the above-described structure and operates. In such an NC machine tool, when the tilt table 2 rotates about the axis 5, the main spindle 4 As shown in Fig. 6 (Y-Z plan view of the NC machine tool in Fig. 5), table 2 interferes in area 1. (In the area to the right of table 2 in Fig. 6, spindle 4 and table 2 interfere. However, since it does not make sense for the main axis to move to this area during machining, it is included in the interference area.) Therefore, it is necessary to set this area 1 as an interference area by using parameters. In FIG. 6, 3 is a peak.

However, if the table 2 moves to the left side position in Fig. 6 due to the rotation of the table 2, for example, the interference area becomes the area 7 in Fig. 6, so that every time the table 2 rotates, the operation Needs to be set again, which is very time-consuming.

Further, when the rotation angle of the table 2 changes every moment during machining, it is impractical for the operator to set the interference area each time, and it is practically impossible to set the interference area.

As described above, in the case of the NC machine tool having the table rotating mechanism, the interference area changes during machining, so that it was difficult or impossible to set the interference area.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem. Even when controlling an NC machining machine capable of processing various surfaces of a work by rotating a table, the present invention provides a An object of the present invention is to provide a numerical control device capable of easily and reliably checking for interference between a tool, a rotating table and a spindle. Disclosure of the invention

The present invention relates to a numerical controller that controls a machine tool that performs processing by placing a processing work on a table having a rotation mechanism, wherein the detection means detects a rotation angle of the rotation mechanism, and the detection means detects the rotation angle of the rotation mechanism. And a means for calculating an interference area based on the calculated rotation angle of the rotation mechanism, and means for performing an interference check based on the interference area calculated by the calculation means.

Further, according to the present invention, the table having the rotation mechanism is configured to rotate around an axis orthogonal to the axial direction of the main shaft.

Further, in the present invention, the calculation means recalculates the interference area when the rotation angle of the rotation mechanism is changed.

Further, in the present invention, the detection means checks at regular intervals whether the rotation angle of the rotation mechanism has been changed.

The present invention further includes a storage unit that stores the table size and the spindle diameter, wherein the calculation unit is configured to calculate the rotation angle of the rotating mechanism based on the detected table size and the spindle diameter stored in the storage unit. Thus, the interference area is calculated based on the calculated values.

Still further, the present invention further includes a storage unit for storing a tool length and a tool diameter of a tool used for machining, wherein the calculation unit includes: a detected rotation angle of the rotation mechanism; a table size stored in the storage unit; The interference area is calculated based on the length and the tool diameter.

With these configurations, it becomes possible to calculate in real time interference areas such as a rotating table and a tool, a rotating table and a spindle, and thus, various surfaces of a workpiece are machined by rotating the table. Simple and reliable even when controlling NC machine tools Indeed, an interference check can be performed. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram for explaining an interference region calculation according to Embodiments 1 to 3 of the present invention.

FIG. 2 is a block diagram showing a hardware configuration according to the first to third embodiments of the present invention.

FIG. 3 is a front chart for explaining operations according to Embodiments 1 to 3 of the present invention.

FIG. 4 is a view showing a tool attached to a spindle according to Embodiment 2 of the present invention.

FIG. 5 is a perspective view showing an NC machine tool having a table rotating mechanism to which the present invention is applied.

FIG. 6 is a diagram for explaining a conventional disadvantage. BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1

Hereinafter, Embodiment 1 of the present invention will be described in detail with reference to FIG. 1 to FIG. 3 and FIG.

Fig. 1 is a diagram for explaining the calculation of the interference area, Fig. 2 is a block diagram showing the hardware configuration, Fig. 3 is a flowchart for explaining the operation, and Fig. 5 is an application of the present invention. 1 is a perspective view showing an NC machine tool having a table rotating mechanism to be used.

First, an interference check method according to an embodiment of the present invention will be described using FIG. 1 and FIG.

In the NC machine tool shown in Fig. 5, tilt table 2 and low table Although the table 15 is provided, in the present embodiment, the object is to interfere with the table surface on which the workpiece 3 is placed (in this case, the upper surface of the rotary table 15). The rotation of the table (rotation about the vertical axis 14) does not change the two surfaces of the table. For simplicity, the following description will be omitted, and the tilt table 2 will be omitted. Is simply referred to as a table (however, the upper surface of the table is assumed to correspond to the upper surface of the table 15 on which the work is placed). First, the interference region when the table is rotated in the plus direction (0 = 0 ° to 90.) will be described. In FIG. 1, a region 1 represents an interference region of the main shaft 4. Ymin + is the minimum value of the Y coordinate of the interference area when rotated in the plus direction, and Zmax + is the maximum value of the Z coordinate. Assuming that the center coordinate of the rotation axis 5 of the table 2 is (Y 0, Z 0), the length from the center to the end of the table 2 is C, and the distance from the center of the rotation axis 5 to the table is H, FIG. The coordinates of point P 1 and point P 2 are

P 1: (Y O + H sin 0 -C cos 0, Z O -H cos 0 -C sin n θ)

Ρ 2: (YO + Hsin0 + Ccos0, ZO-Hcos ^ + CsinΘ)

Becomes Therefore, Ymin + and Zmax + are

Ym i n + (Θ) = Y O + H s i n0-C c o s 0

Z max + (Θ) = Z O -H c os 0 + C s i n ^

Becomes The point (Y, Ζ) on the straight line connecting the points P I and P 2 is

(Ζ-(Ζ 0-H cos) ii (Y-(Υ Ο + H s i n) t an Θ

It is represented by Therefore, the interference area 1 when rotated in the plus direction in FIG. (Z-(Z 0-H cos) ≤ (Y-(Y 0 + H sin) t an Θ,

(Y≥Ymin n, Z≤ Zmax +)

It is represented by

Next, a description will be given of the interference region in the case of rotation in the minus direction (= —90 ° to 0 °). In FIG. 1, a region 7 represents a main axis interference region. Ymax— is the maximum value of the Y coordinate of the interference area when rotated in the minus direction, and Zmax— is the maximum value of the Z coordinate. Ymax— and Zmax— are calculated from the coordinates of points P1 and P2.

Ymax— (= Y 0 + H s i η Θ + C c 0 s 6,

Zmax- (θ) = Z0-Hcos ^ -Csin ^

In FIG. 1, the interference region 7 when rotated in the minus direction is (Z-(Z 0 -H cos 6>)) ≤ (Y-(Υ Ο + H sin) t an Θ ヽ

(Y≤ Ymax-, Z≤ Z max-)

It is represented by

Assuming that the four ends of the main spindle have a diameter D, and the center coordinates of the four ends of the main spindle are (Υ, Z), the coordinates of the point 6 that needs to be checked for interference with the table are (Y + D / 2, Z). In addition, the diameter D is given in one night. Therefore, by checking whether or not the point of (Y + D / 2, Z) is included in the interference area 1 in FIG. 1, it is possible to determine whether or not the movement is possible. When the table rotates in the minus direction, the coordinates of point 9 to be checked are (Y-D / 2, Z), and this point and the interference area 7 are checked.

In normal NC machine tools, the table is fixed, so that the interference area does not change during machining. Although it is not necessary to perform the process again, in the case of an NC machine tool having a table rotating mechanism as shown in FIG. 5, the interference area changes during machining, so in the embodiment of the present invention, each time the table 2 rotates. Recalculate this area as described above.

Next, the interference check between the main shaft 4 and the table 2 will be described in detail with reference to FIGS.

FIG. 2 is a diagram illustrating a hardware configuration of a numerical control device according to the embodiment. The numerical control device is mainly configured with a processor 20. The processor 20 reads the system program including the interference check program according to the present embodiment stored in the ROM 22 via the bus 29, and controls the numerical controller according to the system program as a whole. Control. RAM 23 stores temporary calculation data, display data, input / output signals, and the like. The non-volatile memory 24 is a CMOS or the like backed up by a battery (not shown), and is a parameter that should be retained even after the power is turned off. In the evening, a machining program including the rotation angle 0 command of Table 2 above, an offset Tool correction data such as tool length (tool length L shown in Fig. 4) and tool diameter (tool diameter R shown in Fig. 4), pitch error correction data, spindle end diameter D etc. are stored for each number. You. The non-volatile memory 24 includes the center coordinates (Y 0, Z 0) of the rotation axis 5 of the table 2, the length C from the center to the end of the table 2, and the distance from the center of the rotation axis 5 to the table 2. H Dessert, etc. is also stored.

In the panel 25, a graphic control circuit 25a, a display device 25b, a keyboard 25c, and a software key 25d are provided. The graphic control circuit 25a converts the image information sent from the processor 20 into a displayable signal and outputs it to the display device 25b. As the display device 25b, a CRT, a liquid crystal display, or the like is used. Keyboard 2 5c data input It has operation keys and function keys used for The meaning of the software key 25 d changes according to the operator's screen selection, and the necessary keys are displayed on that screen.

The axis control circuit 26 receives the axis movement command from the processor 20 and outputs the axis movement command to the servo amplifier 27. The servo amplifier 27 amplifies this movement command and drives a servomotor coupled to the NC machine tool shown in FIG. The servomotors are connected to the X, Y, Ζ, Α, and C axes of the NC machine tool shown in Fig. 5, and control the relative movement between the tool and the workpiece of the NC machine tool. The axis control circuits 26 and the servo amplifiers 27 are provided in a number corresponding to the number of axes in the servo mode.

PMC (programmable 'machine' controller) 28 receives M (auxiliary) function signal, S (spindle speed control) function signal, T (tool selection) function signal from processor 20 via bus 29. Then, these signals are processed by a sequence program, output signals are output, and pneumatic devices, hydraulic devices, electromagnetic actuators and the like in the machine tool are controlled. In addition, it receives a signal such as a button signal, a switch signal, and a limit switch of a machine operation panel in the working machine, performs a sequence process, and performs necessary processing for the processor 20 via the bus 29. Transfer the input signal.

The hardware configuration of the numerical control device according to the present embodiment is configured as described above.

Next, the detailed operation of the interference check between the spindle 4 and the table 2 will be described using the flowchart of FIG. The flowchart in FIG. 3 shows the steps from receiving a machining command to moving.

That is,

S1: Reads machining commands from a machining program or the like.

S2: Performs interpolation processing. An interference check is performed during this process. This The specific processing of the steps (S11 to S19, S23 to S26) is described below.

S 11 1: Travel amount per unit time FAT is calculated. F is the moving speed, and ΔT is the cycle of the interpolation processing. The following processing is performed for each cycle.

Next, an interference area is calculated based on the current table rotation angle 0 specified in the machining program, and a dry check is performed (S12 to S17).

The coordinates of the point where interference is checked after F する T movement are (Yn ew, Z new) (Yn ew = Y + D / 2, Z new 2 Z when rotated in the plus direction, Y when in the minus direction) Assuming that the rotation angle of the table is 0 η ew, interference check is performed as follows.

5 1 2: Judge whether the table rotation angle 6> new is 0 new 0. If 0 n e w ≥ 0, go to the next S 13 to S 16.

5 1 3: Calculate the Z-axis boundary value Zmax + (0new) of the interference area.

5 14: Condition 1: Check Znew> Zmax +. If this condition is satisfied, the robot can move because it is not in the interference area.

5 1 5: If Condition 1 above is not satisfied, then calculate the Y-axis boundary value Ymin + (Snew).

5 1 6: Condition 2: Check Ynew and Ymin +. If this condition is met, you can move as well.

If it is determined that 0new <O in S12, the process proceeds to the next S23 to S26.

S23: Calculate the Z-axis boundary value Zmax— (0 new) of the interference area. S24: Condition 1: Check Z new> Zmax—. If this condition is satisfied, the robot can move because it is not in the interference area.

S25: If condition 1 above is not satisfied, then calculate the Y-axis boundary value Ymax— (new). S26: Condition 2: Check Ynew> Ymax-. If this condition is met, you can move as well.

If condition 2 of S16 or S26 is not satisfied, go to the next S17.

S 17: Condition 3: (Zn ew- (ZO-Hcos ^ new))

> (Ynew — (YO + Hcos0new) t a n βnew Check if condition 3 is satisfied.

S18: If any of the above conditions 1 to 3 are satisfied, the actual spindle moves since the position of the spindle end after the movement is not in the interference area and can be moved.

S19: If all of conditions 1 to 3 are not satisfied, it is known that the spindle end after movement and the table are interfering with each other, so stop immediately and issue an alarm. When the conditions are satisfied in S14 to S16 and the mobile device can be moved, there is no need to perform subsequent steps.

S3: If the robot has moved to the end point of the machining command, the processing ends. Otherwise return to S2.

The interference check between the spindle 4 and the table 2 is performed as described above.

Embodiment 2.

In the first embodiment described above, the case where the interference check between the main spindle 1 and the table 6 is performed without considering the length and the diameter of the tool attached to the main spindle 1 has been described. The case where the interference check between the spindle 1 and the table 6 is performed in consideration of the length and diameter of the attached tool 16 will be described with reference to FIG.

That is, as shown in Fig. 4, when the length from the spindle end face to the tip of the tool 16 is represented by L, and the tool diameter is represented by R, when the center coordinate of the spindle end face is (Υ, Z), The coordinates 31 of the point to check for interference with the table when the table is rotated are represented by (Y + R, Z-L). Turn in the minus direction If it is turned, the coordinates 32 of the point to be checked are represented by (Y-R, Z-L).

Therefore, by checking conditions 1 to 3 for these points in the same manner as in the first embodiment, it is possible to check for interference between the spindle 4 and the table 2 in consideration of the length and diameter of the tool 16. It can be performed.

Embodiment 3.

Next, a case where both the diameter of the spindle end and the tool are considered will be described. First, when the table is rotated in the plus direction, when the center coordinate of the spindle end face is (Υ, Z) in the interference area check (S14, S16, S17) in the flowchart of FIG. 6 (Y + D / 2, Z) and coordinate 3

Perform processing to check for interference with the table for two points 1 (Y + R, Z-L). If the table is rotated in the minus direction, the points to be checked are coordinates 9 (Y-D / 2, Z) and coordinates 32 (Y-R, Z-L). Otherwise, it is the same as the first and second embodiments.

Embodiment 4.

In the above embodiment, the case where the interference check is performed at the point between the spindle end face and the tool tip is described, but it is also possible to check a plurality of points of the tool.

As described above, according to the present invention, the interference between the tool system and the table changes due to the rotation of the table itself, so that the conventional dry check took a lot of trouble or could not cope with it. Even in NC machine tools, it is possible to perform an interference check by calculating the interference area in real time, and it is possible to prevent accidents such as interference between the tool system and the table due to a user's programming error etc. And o

In addition, not only the spindle end but also the tool end can be checked for interference. By increasing the number of points to check for interference, it is possible to check the surface of the tool. Industrial applicability

As described above, the numerical control device according to the present invention is suitable for use in checking the dryness of a numerically controlled machine tool having a rotating mechanism for rotating a table.

Claims

The scope of the claims

1. In a numerical controller that controls a machine tool that performs machining by placing a work on a table having a rotating mechanism, detecting means for detecting a rotation angle of the rotating mechanism, and detecting by the detecting means A numerical control device comprising: a calculating unit that calculates an interference area based on the rotation angle of the rotating mechanism that has been set; and a unit that performs an interference check based on the interference area calculated by the calculating unit.

2. The numerical control device according to claim 1, wherein the table having the rotation mechanism rotates around an axis orthogonal to an axial direction of a main shaft.

3. The numerical control device according to claim 1, wherein the calculation means recalculates the interference area when the rotation angle of the rotation mechanism is changed.

4. The numerical control device according to claim 1, wherein the detection means checks at regular intervals whether the rotation angle of the rotation mechanism has been changed.

5. The storage unit that stores the size and the spindle diameter of the table is provided, and the calculation unit is configured to determine the interference area based on the detected rotation angle of the rotation mechanism and the table size and the spindle diameter stored in the storage unit. 2. The numerical control device according to claim 1, wherein the numerical control is calculated.

6. A storage means for storing a tool length and a tool diameter of a tool used for machining is provided, and the calculating means is provided with: a detected rotation angle of the rotating mechanism; a table size stored in the storage means; a tool length and a tool diameter. 2. The numerical control device according to claim 1, wherein the interference area is calculated based on