JPS609636A - Spindle position correction device of machine tool - Google Patents

Abstract

PURPOSE:To have accurate correction of positional relation between the center of the reference cylindrical surface of a work to be processed and the spindle, which is likely to be out of alignment, by setting a contact sensing tool fitted on the spindle as in contact with two or more points of the reference cylindrical surface. CONSTITUTION:When that side face of a work to be processed W formed with reference cylindrical surface H1 is indexed into the processing position facing the spindle 3 by a rotary table 1 of the spindle position correcting device of a machine tool, a dislocation sensing means 5 puts a contact sensing part TS in contact with a plurality of points of the reference cylindrical surface H1 by relatively moving the spindle 3 fitted with a tool 6 having said sensing part TS through the motion of the spindle head 2 so as to sense how much and in which direction the center of the abovementioned cylindrical surface H1 is dislocated from the imaginatory point where the center should be located according to theory. Thus the positional relation between the center of the surface H1 and the spindle can be corrected accurately.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a spindle position correction device for a machine tool, and in particular to a device for correcting the spindle position of a machine tool, in particular a workpiece that has a reference cylindrical surface formed on one of a pair of mutually parallel side surfaces and is mounted on a rotary table. The present invention relates to a spindle position correction device for a machine tool, which processes the other of the pair of side surfaces using this reference cylindrical surface as a position reference.

<Prior art> As shown in FIG. 1, a pair of holes H are formed on a pair of opposing side surfaces and whose centers are located on the same axis.
1. When drilling H2 with high precision, conventionally, before drilling hole H+,
If the centering method shown in No. 55 is not used to position the spindle S at the center of the hole H+, but also before machining the hole H2, it will not be possible to perform compact machining. could not.

That is, when the central axis OW of the hole H1lH2 is placed so as to pass through the rotation center Or of the rotary table RT, the installation error and the hole 1 (+).

If we consider a case where the center axis Ow of 6H+ and H2 deviates from its original position by d in one direction of the X-axis as shown in Fig. 2 due to the position error of H2, the main axis S will perform centering operation. , the hole H is corrected by d in one direction of the X axis.
1 can be processed accurately, but in this state, the workpiece W can be machined by 180 mm.
When the rotation axis rotation hole F (2) is indexed to the machining position opposite to the main axis S, its center Ow is located at the rotation center of the rotary table RT in the X-axis direction with respect to Or, as shown by ow' in Fig. This results in a misalignment of 2d with respect to the center axis O3 of the spindle S. Therefore, the hole H2 cannot be machined with high accuracy unless the centering operation is performed again before machining the hole H2. Become.

In this way, in the conventional machining method, the 6-output operation must be performed both before machining hole H1 and before machining hole H2, which not only increases the machining cycle time but also increases the machining process. If the holes H and H2 were misaligned before, there was a problem in that they would be machined with their centers misaligned, making it impossible to obtain high concentricity.

<Purpose of the Invention> Therefore, the present invention aims to improve the inner peripheral surface of a hole formed in a workpiece, etc.
Even if the positional relationship between the center of a reference cylindrical surface serving as a position reference and the main axis is shifted by rotating the rotary table by 180 degrees, this can be accurately corrected.
It is an object of the present invention to enable machining of the other side surface with high accuracy using the center of a reference cylindrical surface formed on one side surface as a position reference without performing centering operation again.

<Configuration of the Invention> FIG. 3 is an overall configuration diagram for clearly demonstrating the present invention. The reference cylindrical surface H of the workpiece W is determined by indexing the rotary table 1.
When the side surface on which , is formed is indexed to a machining position opposite to the spindle 3, the deviation detection means 5 moves the spindle 3, on which the tool 6 equipped with the contact detection part TS is mounted, to a relative position by moving the spindle head 2. By moving the contact detection unit TS, it can be brought into contact with multiple locations on the base 11 + cylinder and H surface, and the center of the reference cylindrical surface H+ can be determined by how much and in which direction it deviates from the theoretical center (virtual center). Detect whether there are any.

Thereafter, when the other side of the workpiece W is indexed by the indexing of the rotary table 1 by the drive mechanism 4, the correction means 7 is activated in response to this, and the correction means 7 is activated according to the amount of deviation detected by the detection means 5. The main shaft 3 is corrected and moved in the direction opposite to the direction of the detected deviation by the amount.

As a result, the axis of the main shaft 3 coincides with the central axis of the cylindrical surface I-I 2, which is concentric with the reference cylindrical surface H formed on the other surface, and the cylindrical surface H2 is raised without performing another centering operation. This allows for precise processing.

<Example> Embodiments of the present invention will be described below based on the drawings.

In FIG. 4, 10 is a bed of the machine body, and on this bed Iθ, a rotary table 11 on which a workpiece W is placed is placed on a slide table 12 movable in a direction perpendicular to the plane of the drawing (X-axis direction). is installed, and the spindle head 13 is moved upward (
A column 14 that is movably guided in the Y-axis direction is movably guided in the left-right direction (X-axis direction). The slide table 12 is moved in the X-axis direction by a servo motor SMX fixed to the bend 10, and the spindle head 13 is moved by a servo motor SM attached to the rear end of the head 10.
Z and the servo motor S attached to the top of the spindle head 13
MY in the X-axis direction and the Y-axis direction.

Further, the rotary table 11 is rotated by a servo motor SMB fixed to the slide table 12.

And these issues - Bomoke SMX, SMY.

SMZ and SMB are connected to the numerical control device main body 30 via the drive unit I5, and are rotationally driven by distribution pulses output from the numerical control device main body 30.

Reference numeral 17 denotes a spindle mounted on the spindle head 13, and when hollowing a workpiece W, a hollowing tool T having a contact portion TS fixed to the tip for contact detection is mounted thereon.

A contact detection coil 20 connected to the AC power supply 19 via a current detection resistor R1 is disposed on the outer periphery 91 of the product 1 of the spindle head I3, and the magnetic flux surrounding the spindle 17 is Therefore, when the contact surface formed on the outer peripheral surface of the tip of the contact portion 1゛S for contact detection comes into contact with the workpiece W, an induced current is generated through the induced current path shown by the broken line in Fig. 1. A current flows and lowers the impedance of the coil 20. When the impedance of the coil 20 decreases, the excitation current increases and the voltage generated across the resistor R1 increases, and the contact detection circuit 18 uses this increase in voltage signal to detect the workpiece. W
and detects the contact of the contact portion TS and sends out a contact detection signal TDS.

The numerical control device main body 30 is a known numerical control device that distributes pulses to each axis based on NC data programmed on the paper tape 21 read by the tape reader TR, thereby machining the workpiece W. This numerical control device main body 30 has M programmed as NC data.
A data output terminal for outputting code data and a product manual operation terminal for accepting external manual operation commands are provided. When the numerical control device main body 30 reads M code data as NC data, it outputs the M code data from the output terminal, then stops NC control and enters a standby state, and is given an auxiliary function completion signal MFIN from the outside. , the standby state is canceled and NC control is restarted. While in the standby state, pulses are distributed to each axis in accordance with a pulse-like pulse distribution command given to the manual operation terminal.

Most of the M code data is given to the concave high-power control circuit, but the M code data from M52 to M5 (i) is given to the spindle position correction device 40.The spindle position correction device 40 is - As an example, M5 is configured by a microcomputer and is configured from the numerical control device main body 30.
When the auxiliary function codes 2 to M56 are given, the numerical control device main body 30 is switched to manual mode, and then axis designation data and positive/negative pulse distribution commands are sent to the manual operation terminal, and the numerical control device main body 30 is sent to the manual operation terminal. Distributes pulses to each axis,
As a result, feed control for measuring deviation and correcting the spindle position is performed.

Table 1 shows the operations performed by the spindle position correction device 40 when the codes M52 to M57 are given, and the spindle position correction device 40 performs these operations as shown in FIGS. 5 to 9. It is designed to be executed according to a flowchart.

Table 1 As shown in Fig. 4, if holes H1 and H2 formed in a pair of mutually parallel side surfaces of the workpiece W are to be bored, the holes H1 and H2 will be bored as shown in Fig. 10. A numerical control program is created and read into the numerical control device main body 30. In this numerical control program, block N0OI,
N0O2 is for inserting the contact part TS of the boring tool T attached to the main spindle 17 into the hole Hr, and blocks N003 to N008 perform centering operation to align the center of the main spindle 17 into the hole. 111, and detects the amount of deviation dx in the X-axis direction between the temporary center 01 initially positioned by the program and the real center ○W. Also, block N0O9 has hole H
This is for hollowing I, blocks N010 to N
Until 014, pull out the boring tool T from hole I11°
ζ, program to rotate the rotary table 11 by 180 degrees,
Block N015 is a program for correcting the position of the main spindle 17, and block N016 is a program for boring the hole H2.

The operations of the numerical control device main body 30 and the spindle position correction device 40 will be explained below according to this numerical control program.

First, GOO programmed in block N001
When Y-6000O5200MO3 is executed, the numerical control device main body 30 operates the drive unino l-15 accordingly.
The spindle head 13 is moved at a rapid traverse speed by distributing pulses to position the contact portion TS on the spindle 17 at the virtual center 01 on the program of the hole H1, and the spindle 17 is rotated at a specified speed. . Then, by executing Z-20000 programmed in the subsequent block N002, the contact portion TS portion of the hollowing tool T on the second main shaft 17J is inserted into the hole HI.

After this, it is programmed in block N 003.
When X4500 M52 is read, the main shaft 17 is moved to the X axis + as shown in FIG.
After moving for 4500 pulses in the direction, the code data of M52 is output to the spindle position correction device 40, and the spindle position correction device 40 responds to this by distributing pulses for centering operation.

That is, the spindle position correction device 40 first switches the numerical control device main body 30 to the pivoting operation (5).
0), the counter MVC for detecting the movement amount is reset to I-L (
51), after this, drive a positive feed pulse to XIIi+b one pulse at a time via the numerical control device main body 30 until it is detected that the contact portion 'S has contacted the inner peripheral surface of IIl' 1.5 At the same time, the counter MVC detects the number of pulses sent out before contact (52) to (54).

After this, the number of pulses sent before contact is increased to 6.
55), return the contact portion TS to its original position by distributing the same number of negative pulses as ε1 to the X-axis 5(i), return the numerical control device main body 30 to automatic mode, Signal M F I indicating completion of processing M52
N is sent to the numerical control device main body 30.

Also, after this, when the X-9000M53 programmed in block N0O4 is read, the numerical control device main body 30 moves the main shaft 1ll-1113 9000 in one direction of the X axis.
After fast-forwarding by the amount of pulses, the code data of M53 is supplied to the spindle position correction device 40, which causes the spindle position correction device 40 to execute the program shown in FIG. 6 and perform numerical control in the same way as in the previous case. Set the device body 30 to manual mode 60) Send a negative pulse to the X axis until the contact part T'S comes into contact with the surface on the opposite side of the hole H+, and detect the number of distributed pulses 82 62) to (65) ), then (ε
1+82)/2 is calculated 66), this value is stored as the spindle position deviation amount dx (67), and a number of positive pulses corresponding to dX are distributed to the X axis (68).

By dx or moving the spindle 17 in the X-axis stopping direction, when the program of X4500 of block N0O5 is executed, the axial center position of the spindle 17 is It is positioned at a position where there is no deviation in direction.

Furthermore, following this, Pro Tsuk N006 to N008
Programmed in Y4500 M54, Y-9
When the programs 000M2S and Y4500 are executed sequentially, the above-mentioned operation is performed in the Y-axis direction, and the main shaft 17 is moved to Y1111 at 2 with respect to the actual center Qw of the hole H+.
It is positioned so that there is no displacement in any of the 11 directions.

This results in cot z-1000 of block N0O9
0, Floo allows hollowing of hole II + to be performed with high precision. And after this, block N0
After the spindle 17 is stopped at a fixed position by MO4 of IO so that the cutting tool of the boring tool T faces upward, block N00
With the GOOY-100 of 1, the main shaft 17 is shifted to a position where the cutter does not interfere with the cutting tool when pulling out the boring tool.
After that, according to the program of block N012,
Hole] - The filling T is a hole! -II Extracted from I.

On the other hand, when the block No. 131800 brush 1g of block N013 is executed, the rotary table 11 is rotated 180 degrees, and after this, when the block I cock N014 M56 is read, the code 1-'' of M56 is set to the main shaft position. The information is supplied to the correction device 40, and in response to this, the spindle position correction device 40 performs the spindle position correction processing shown in FIG.

That is, the spindle position correction device 40 is connected to the numerical control device main body 3.
After switching 0 to manual mode (90), the above-mentioned M53
double the amount of deviation dx stored when executing (91), and determine whether or not the amount of deviation is positive (92);
If it is positive, distribute the number of negative pulses corresponding to 2dx, which is twice the amount of deviation, to the X axis (93), and if it is negative, distribute the number of positive pulses, which corresponds to 2dX, which is twice the amount of deviation, to the X axis. Distribute (9
4).

As a result, the boring tool 'P is moved from the position shown by the solid line in FIG. The 2dX shift that occurs between them is completely corrected, and the main axis 17 is aligned with the hole Hl.

It is positioned without deviation in the X-axis direction with respect to the actual center Ow of H2.

And after this, Y1003200 of block N014
The MO3 program corrects the deviation in the Y-axis direction caused by the release operation of the cutting tool, and also
is rotated and GOI Z-, 150 of block N015
By executing the program 00Floo, each hole H2 or hole III is machined concentrically and with high accuracy.

In the above embodiment, the holes H1 and H on the workpiece W are
The workpiece W is taken so that the axis of the rotating tape passes through the center of rotation Or of the rotary tape 1.
2 may be offset from the rotation center Or of the rotary table 11. In this case, if the amount of deviation in the X-axis direction between the rotation center Or and the centers of holes H+ and H2 is D, then after rotating the rotary table 11 by 180 degrees, the main shaft 17 is
All you have to do is program it to move only D.

Further, as shown in FIG. 13 (al), when the hole H+ formed on one side surface is not concentric with the hole H3 formed on the other side surface, the hole H3 is located at the center of the hole H+. It can also be applied when processing with high precision using the cylindrical protrusion L1 as a reference.Furthermore, as shown in FIG. 2. Machining the outer circumferential surface of hole H4
It can also be used when machining the inner peripheral surface of.

In addition, in the above embodiment, the hole serving as the reference cylindrical surface was detected, but the contact portion TS is moved from the center on the program and brought into contact with three locations of the hole, and the coordinates at this contact point are determined. The deviation may be detected by calculating the center coordinates based on the values and calculating the deviation between the calculated center coordinates and the center on the program.

<Effects of the Invention> As described above, the present invention is activated when one side surface is indexed to the machining position, and the relative movement of the spindle causes the contact detection tool attached to the spindle to move toward the reference cylindrical surface. a deviation detection means that is brought into contact with a plurality of points and detects the amount and direction of deviation between the actual center and the virtual center of the reference cylindrical surface based on the contact positions; a correction means that is enabled before the start of the rotation and corrects the relative position of the main shaft in a direction opposite to the direction of the detected deviation by an amount corresponding to the detected deviation amount;
After rotating the axis, the center of the main spindle can be positioned in a positive radius with the center of the reference cylindrical surface as a reference, and the other side can be processed using the center of the reference cylindrical surface formed on one side as a reference. It has the advantage of being able to perform the process with high precision and efficiency.

[Brief explanation of the drawing]

Figures 1 and 2 are just diagrams to explain the problems of the conventional method.
FIG. 1 is a plan sectional view of the workpiece W, FIG. 2 is a diagram showing the movement of the center due to rotation of the workpiece W, FIG. 3 is an overall configuration diagram to clarify the present invention, and FIGS. 4 to 13 Figures (bl shows an embodiment of the present invention, Figure 4 is a schematic diagram of a machine tool with a block diagram showing a control circuit, Figures 5 to 9
The figure shows M52 to M56 from the numerical control device main body 30 in Figure 4.
Flowchart 1 shows the operation of the spindle position RFI 40 when the code is output. Figure 10 is a diagram showing an example of a numerical control program.
Figure 1 shows the positional relationship between the center of 2 and the center of the main shaft 17.
2 is a diagram showing the movement of the contact portion TS during centering operation, and FIGS. 113(al) and (b) are diagrams showing other additions to which the present invention can be applied. rotary table, 5... displacement detection means;
7... Correction means, 13... Spindle head, 17... Spindle, 18... Contact detection circuit, 20... Coil, 30...
...Numerical control device main body, 40...Spindle position correction device,
T... Boring tool, Hl, H2... Hole, SMB, S
MX, SMY. SMZ...servo motor, TS...contact part, W...
・Workpiece. Patent applicant Toyota Machinery Co., Ltd. Figure 1 T Figure 3 Figure 5 Figure 6

Claims (1)

[Claims] (11) A workpiece in which a reference cylindrical surface is formed on one of a pair of parallel side surfaces is placed on a rotary table, and the other of the pair of side surfaces is machined using this reference cylindrical surface as a position reference. In the machine, it is activated when the one side surface is indexed to the machining position, and the contact detection tool attached to the spindle is brought into contact with multiple locations on the reference cylindrical surface by relative movement of the spindle, and this contact position is detected. a deviation detection means for detecting the amount and direction of deviation between the real center and the virtual center of the reference cylindrical surface with reference to the reference cylindrical surface; A spindle position correction device for a machine tool, comprising a correction means for correcting the relative position of the spindle in a direction opposite to the direction of the detected deviation by an amount corresponding to the amount of deviation.