JPS5962919A - Motor driving control system - Google Patents

Abstract

PURPOSE:To attain miniaturization and low cost, by using one set of constant position stop circuit in common with the control of constant position stopping of main spindle and the deduction of the rotating position of a blade stand. CONSTITUTION:In positioning the main spindle 10, switches SW1-SW3 are switched to the spindle position (shown in figure) and a reference position data is inputted to the constant position stopping circuit 104. Then, the circuit 104 positions the main spindle 10 to the commanded position in cooperation with a servo unit 101. Further, in positioning the blade stand 15 and selecting a prescribed tool, the switches SW1-SW3 are selected to the blade stand side and the tool position data is inputted to the stop circuit 104. Thus, the circuit 104 positions the blade stand 15 in cooperation with the unit 101 to select a commanded tool. Since one constant position stop circuit is used in common, miniaturization and low cost are attained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a motor drive control system, and more particularly to a motor drive control system in which one fixed position stop circuit and servo unit can be used in common for main spindle fixed position stop control and rotational position indexing of a tool post. Regarding.

In turning centers, etc., the main spindle, or workpiece, must be rotated at a commanded rotational speed during turning processing.
Furthermore, when machining screw holes, holes, key grooves, etc. after turning, the spindle must be accurately positioned at a predetermined position.

FIG. 1 shows a screw hole 2a at a predetermined rotational position of a workpiece 1 that has been subjected to turning processing.

2b, 2C, 2d, a keyway 6, and holes 4a, 4b are provided. The machining of these screw holes, key grooves, and holes is performed as follows, with reference to FIG. That is, - First, the workpiece 12 held by the chuck 11 is
Lord'i! The III drive motor 13 is driven to position it at a predetermined rotational position. Next, the main shaft 10 is fixed with the clamp mechanism 14 (mechanical clamp), and then the tool rest 1 is
5 to select a predetermined rotary tool 16, the DC motor 17 is driven d+JJ to rotate the rotary tool 16 to machine a screw hole. My father used the main spindle 10 (workpiece 12) for turning.
) at a predetermined rotational speed, the tool post 15 is rotated to select a predetermined turning tool 18, and then the vaginal turning tool 18 is moved to a predetermined commanded shape. As a result, the workpiece 12 is subjected to turning processing according to the commanded shape.

As mentioned above, in turning centers etc., the spindle 1
The function of stopping the tool in one position and the function of indexing (positioning) the tool rest 15 and selecting a predetermined tool are required. For this reason, in the conventional drive control system, a fixed position stopping circuit for stopping the spindle 10 at a fixed position and an indexing mechanism for indexing the tool rest 15 using a cylinder are provided separately. However, since both the fixed position stop circuit and the indexing mechanism are provided in this way, this results in an increase in size and cost.

From the above, the present invention allows a single electrical fixed position stop circuit to be shared by the main spindle 10 and the tool post 15, thereby making it possible to reduce costs and downsize, and furthermore, to provide a motor that enables highly accurate positioning of the tool post. The purpose is to provide a driving i[i+1 method.

FIG. 5 is a block diagram of an embodiment of the present invention, and the same parts as in FIG. 2 are given the same reference numerals. A line s1 is a power line that applies a drive voltage from the servo unit 1o1 to the spindle lateral movement motor (referred to as a spindle motor) 13, IJ! 52 is a speed feedback line that applies the actual speed voltage from the tachometer 102 that detects the rotational speed of the spindle motor 13 to the servo unit MO1; ,
Position feedback MA that applies position pulses PP (N pulses generated per rotation) generated from the position coder to the fixed position stop circuit 104 each time the main 1i111 rotates by a predetermined angle. 10
1 is a power line that applies a drive voltage to the tool post drive motor 195, t#JTz is the power line that applies the drive voltage to the tool post, and the actual speed voltage from the tachometer 1o6 that detects the rotation speed of the drive motor 105 is applied to the no-small unit 1o1. Velocity feedback line, line T
3 is a position coder 10 every time the tool rest 15 rotates once.
7 and a position pulse PP' generated from the position coder 107 every time the turret rotates by a predetermined angle (N pulses generated per rotation) are applied to the fixed position stop circuit 104, respectively. This is the return line.

To determine the position of the main shaft 10, send the main jl+lI1 selection signal and command position data from the NG device 10 to the high-power circuit 1.
Enter in 09. The high-power circuit 109 thereby outputs a switching signal to switch the switches SW□ to SW3 to the spindle side (as shown in figures k and 1.i), and inputs the command position data to the localization and stop circuit 104. When the command position data is input, the fixed position stop circuit 104 stops the servo unit 10.
1 and 6 to position the main 111i 1104 at the commanded position in cooperation with 1 and 6. On the other hand, to position the tool rest 15 and select a predetermined tool, the NC device) Q 1013 receives the turret selection signal and command tool data. Strong current circuit 1 (1 input to 19, strong current circuit 109 outputs a switching signal and switches SW1
~SW3 is switched to the tool rest side, and the tool position 1f7: data is input to the fixed position stop time Iiδ104. When tool position data is input, the fixed position stop circuit 104 positions the tool rest 15 in cooperation with the search unit 101, and selects the commanded tool.

Figure 8114 is a block diagram of the servo system when switching to the spindle side. Note that the same block diagram is obtained when switching to the tool post side.

When the turning process is completed and the stage is reached to stop the spindle motor 13, the command speed CV output from the speed command circuit 101a in response to the spindle positioning IR stop command from the NC device becomes, for example, zero, and the rotational speed of the spindle motor 13 becomes zero. Slow down.

Then, when the direct mL of the stop, that is, the speed becomes considerably low, the movable one piece of the changeover switch 101b is switched to the contact side. Fixed position stop 11J The m11 circuit 104 outputs a position according to the deviation between the commanded stop position and the current position.
Outputs D (analog voltage). In addition, in the localization and stop control circuit 104, 104a is the position coder 10.
104b is a counter that is set to a numerical value N when the 1-rotation signal RP is generated, and its contents are subtracted every time a pulse PP is generated. 104b is a DA converter that converts the contents of the counter 104a into a digital/analog voltage (DA exchange). Vessel・、10
4C is a command '7 having a value according to the command stop position data.
d IE CV Command voltage generation that generates T, 104
This is an analog subtracter that outputs a position deviation voltage 1?FD which is the difference voltage between d and command voltage CvT (!:).

Now, if the value of the command direct voltage CVT is set to 1/2 of the peak value of the DA converter output voltage DAV, the one revolution signal R as shown in FIG.
A sawtooth position deviation voltage 1 voltage RPD that loses the zero level at a point 180 degrees from the generation point of P is output from the localization 11"L stop circuit 104, and the main shaft is moved exactly from the point of generation of the 1 rotation signal RP. It will stop at a position of 180°.In other words, if the commanded stop position is shifted by 180° from the generation position of No. 46 RP for one rotation, the pupil of the command voltage CVT will be set to D.
The command stop position must be 1/2 d of the peak value of AY, and the command stop position is 90° from IL [1 rotation signal generation position, 27
If the position is shifted by 0°, the value of the command voltage CVT must be set to 574.1/4 of the peak value of nDA-V.

Now, if the changeover switch 103a is switched to the contact side,
The speed control circuit 101C has position 1, deviation RPD, and actual speed AV.
It outputs the difference between the two and the a pressure, and controls the position of the servo so that the positional deviation RPD becomes zero. That is, a position control feedback system 414 is formed by the speed control circuit 10IC, the spindle motor 13, the spindle 10, the position coder 103, the localization and stop control circuit 104, and the changeover switch 101b, and the predetermined portion of the spindle is positioned at the commanded stop position d. Ru.

According to the present invention, one servo unit 101 and fixed position stop circuit 104 are shared by the main spindle and the turret, and can be switched as appropriate with a switch, which makes it possible to reduce costs and downsize, and further improve cylinder accuracy. It is now possible to position the turret and spindle.

[Brief explanation of the drawing]

Fig. 1 is a machining state diagram in which screw holes, key grooves, etc. are made on the predetermined rotational position of the turning machine.
The figure shows a connection diagram of the main shaft drive system and the turret drive system, Figure 3 is a block diagram of an embodiment of the present invention, Figure 4 is a block diagram of a fixed position stop circuit, and Figure 5 shows waveforms of each part of Figure 4. It is a diagram. 10... Main shaft, 13... Main shaft drive motor, 15.
...Turret post, 101...Servo unit, 102,1
06...Zokometer, 103,107...Position coder, 104...Fixed position stop fltll ff11
Circuit, 105... Turret drive motor, 108...
NG device, 109... Strong electric circuit patent applicant Fanuc Co., Ltd. representative patent attorney Sangai Tsuji - 2 people Figure 1 4b 4t 22b 2t. Figures 1 to 3 Ash No. 40 Early Figure 5

Claims (1)

[Claims] A predetermined part on the spindle is positioned at a predetermined rotational position, a tool post is positioned, a predetermined tool is selected, and the tool attached to the tool post is rotated to process the workpiece attached to the spindle. , or in a motor drive control system for machine tools that rotates the workpiece by rotating the spindle and moves a tool attached to the turret relative to the workpiece to process the workpiece, the spindle drive motor and the turret One fixed position stop circuit is provided in common with the drive motor, and a switch means is activated by a motor switching signal to selectively connect the power line and signal line of one of the motors to the fixed position stop circuit. A motor drive control method characterized by controlling the drive of a motor.