SU1302240A1 - Self-adjusting programmed control system - Google Patents

Abstract

The invention relates to the field of software control of metal-cutting equipment with automatic control of feed speeds depending on the magnitude of the load on the cutting tool and can be applied to software-controlled machine tools operated from a magnetic tape. The aim of the invention is to expand the range of automatic adjustment of the feed rates of the machine. System contains a control unit, feed drives, a load sensor, a comparison element, a load sensor, a copy control unit, a copy feed drive, a template, a copy sensor probe, displacement sensors. With increasing load on the cutting tool, the feed speed of the machine decreases, and decreasing load increases, which leads to stabilization of the load on the cutting tool. 2 hp ff, 7 ill. with (L with about INO Yu .4

Description

The invention relates to the field of software control of metal-cutting equipment with automatic control of feed speeds depending on the magnitude of the load on the cutting tool and can be applied to software-controlled machine tools operated from a magnetic tape.

The aim of the invention is to extend the range of adjustment of the feed speeds of the machine.

Fig. 1 shows the scheme of a self-adapting software control system; FIG. 2 shows a structural diagram of one of the control channels of the control unit; FIG. 3 shows a structure of the copy control unit circuit J of FIG. 4; a block diagram of a device for recording a program on a magnetic tape and reproducing it; FIG. 5 - load unit j in FIG. 6; unit copy speed setter in FIG. 7; structural diagram

copy sensor

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The self-adjusting software control system contains a control block 1, a drive 2 of the machine 3 feeds, on whose desk a part 4 is installed, processed by a cutting tool 5, acting on a load sensor 6, a reference element 7, a load setter 8, a copy control block 9, a drive 10 feeds of the copying device 11, on the table of which the template 12 of the workpiece 4 is installed, with which the probe 13 of the copy sensor 14 contacts, the sensor 15 moves along X and Y coordinates, the output 16 moves sensor 15 (FIG. 1).

Each control channel of control unit 1 contains a first amplifier 17, a phase disk 18, a second amplifier 19, and a third amplifier 20. (FIG. 2)

The copy control unit 9 contains amplifiers 21 and 22, phase discriminators 23 and 24, amplifiers 25 and 26, amplifiers 27 and 28, phase-shifting element 29, output of amplifier 30, copy speed setting unit 31 (FIG. 3). The control unit 1 contains the control channels 32 and 33 along the X and Y coordinates (FIG. 1).

The drive 2 innings (FIG. 1) contains, respectively, for each coordinate thyristor converters 34 and 35,

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motors 36 and 37; gearboxes 38 and 39; feedback sensors 40 and 41. A device 42 for recording a program on a magnetic tape and reproducing it (FIG. 4), respectively, for X and Y coordinates, recording amplifiers 43 and 44, amplifiers 45 and 46, mode switch 47, magnetic head 48, Tape mechanism 49 serves to move the magnetic tape 50, the load setting unit 8 (fig. 5) consists of a variable resistor 51, on the axis 52 of which a handle 53 is mounted, the rotation of which sets the maximum allowable load on the cutting tool 5 on the output tool 5 five,

The copying speed setting device 31 (FIG. 6) consists of a variable resistor 56, on the axis 57 of which a handle 58 is mounted, the rotation of which establishes on a scale 59 requires a copying speed corresponding to a certain voltage at output 60,

The feed drive of the copier (FIG. 1) contains successively integrated thyristor converters 61 and 62, respectively, for the X and Y coordinates, motors 63 and 64, gearboxes 65 and 66,

Copy sensor 14 (Fig, 7). consists of a copier 67, connected to the amplifier 68 of the copier 11,

The displacement sensors 15, which consist of the displacement sensor 69 of the X coordinate and the displacement sensor 70 of the Y coordinate (FIG. 1), are connected with the driving screws of the longitudinal and transverse feeds of the copying device 11,

A replacement probe 13 is inserted into the copier 67, the diameter of which must correspond to the diameter of the cutting tool 5. The copier 67 has a cylindrical shape.

Inside the device 67, four inductive sensors are installed crosswise to receive two signals from the copying device 67 as a function of the sin and cos deflection angle of the copy probe 13 with respect to any coordinate axis. Sensor anchor and copying probe 13 are suspended on the membrane to the body of the device 67. When the copying probe is deflected

13 from the vertical, the membrane is deformed and the air gaps and, consequently, the inductances of the sensors change. In order to reduce friction errors when traversing the circuit, the copying probe 13 rotates in rolling bearings.

In the copying device 67, the primary windings are diametrically located between the coils are connected in series, and the secondary windings of these coils are connected in series to each other, as a result of which the magnitude and polarity of the signals arriving at the amplifier 68 of the copier depend on the size and direction of the coils. reject the copy probe 13.

Before machining the first part 4, the system operator performs the following operations: installs part 4 on the machine table 3, sets the cutting tool 5 into the machine spindle 3, sets the allowable load force on the cutting tool according to the technology to workpiece 4 using the load adjuster 8; on the copier table 11 sets the template 12 of the workpiece 4j into the spindle of the copy sensor 14 sets the probe 13, the diameter of the displacement sensors 15 and the tracks of which is equal to the diameter of the cutting tool 5i sets the working parts of the machine 3 and the copier 11 to the initial (zero) position, the distance of the cutting tool 5 from the contour of the part 4 and the distance of the probe 13 from the contour of the template 12 should be the same, includes a tape-driving mechanism 49 of the recording device 42; includes rotating the cutting tool 5J manually brings the probe 13 to the contour of the template 12, and the movement sensors begin to rotate and provide control information to the control unit 1 and to the device 42.

The tool 5 approaches the contour of the part 4. When pressing the probe 13, the contour of the template 12 turns on 50 automatically bypassing the contour of the template 12 with the probe 13. The copying speed setting device 31 sets the initial copying speed specified in the part 4 processing technology. The sensors 55 15 displace the control information that, through the control unit 1, enters the 2 feed drive that moves the working bodies

machine 3, repeating movements of the working bodies of the copier 11. In parallel, the control information from the displacement sensors 15 is fed to output 16 for recording onto magnetic tape 50. Processing of part 4 has begun.

During machining of part 4 there may be three modes of operation. The first mode - part allowance of 4 nominal. The processing speed of the part 4 corresponds to the copying speed of the contour of the template 12, which is set by the copying speed setter 31.

The second mode — part 4 allowance increased, i.e. became more nominal, while the load ya of the cutting tool 5 increases. This change senses the load sensor 6 and through the comparison element 7 and the summing amplifier 30 reduces the output voltage of the amplifier 30, respectively, and this leads to a change in the output voltage of the amplifiers 25 and 26, which accordingly reduces copying speed.

Reducing the copy speed causes a decrease in the speed of rotation.

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The frequency of the control signals at the input of the control unit 1 is reduced. Reducing the frequency of the control signals reduces the speed of the 2-feed drive and, accordingly, reduces the machining speed of the part 4. The machining speed decreases until the load on the cutting tool becomes nominal.

The third mode - the allowance of part 4 is reduced. became less than nominal. This reduces the load on the cutting tool 5. This change senses the load sensor 6, which, through the comparison element 7 and the summing amplifier 30, increases the copying speed and, consequently, the processing speed of the part 4.

So in the process

Parts 4 first changes the load on the cutting tool 5. The task on the load adjuster 3 remains constant for the entire time of machining the part 4. And it changes only when the part 4 and the cutting tool 5 are changed.

parts 4, the tape drive, the mechanism 49 stops, the tape 50 is rewound, the switch

47 modes are set to the Play position and the machine 3 can process the following parts 4 according to the program recorded on magnetic tape 50,

The control unit 1 operates as follows.

The input of amplifier 17 receives a sinusoidal signal from one of the displacement sensors 15 and is amplified to a square wave signal with a duty cycle of two. A sinusoidal signal is fed to the input of amplifier 19 from feedback sensor 40 and is amplified to a square-shaped signal 15

with a duty cycle of two. Square-shaped signals from amplifiers 17 and 19 are fed to the corresponding inputs of phase discriminator 18. The output signal of phase discriminator 18 is a DC signal, the amplitude and polarity of which depend on the phase shift of the input voltages, t , from signals from one of the displacement sensors 15 and feedback sensor 40.

Amplifier 20 is a direct current amplifier for amplifying the output of phase discriminator 18. The magnitude of the phase shift determines the rotational speed of the 2 feed drive, and the direction of the phase shift determines the rotation direction of the 2 feed drive.

The feedback from the feed drive 2 is carried out in the phase of the control signal,

At the first input of the phase discriminator 18 s amplifier 17, the working signal U sin (iot + 4) is received. The phase of the boar signal determines the law of changing the controlled coordinate.

The second input of the phase discrimination torus 18 is fed through the amplifier 19 to the feedback signal (a)), where H is the phase of the feedback signal. As a result of comparing these with the signals at the output of the phase discriminator 18, a signal is generated, the constant component of which is 6 proportional to (b) xy-f).

This voltage is the error signal of the follower drive 2 2 feeds.

Further, this signal is amplified by a drive of 10 feeds, i.e. The change in power by the driver 20 and through the thyristor bypass of the probe with the probe 13 of the pattern contour 34 is supplied to the motor 36, which tends to set the controlled coordinate to such a polo12. Thus, the change in the amplitude of the input signal of the amplifier 30 by turning the knob handle 58

error when the error signal is equal to or close to zero.

The copy control unit 9 operates as follows. Amplifiers 21,22,27 and 28 are designed to convert sinusoidal signals. signals arriving at their inputs, and square-wave signals. With a duty cycle of two, which arrive at the corresponding inputs of phase discriminators 23 and 24, DC amplifiers 25 and 26 serve to amplify the output signals of the corresponding phase discriminators 23 and 24. Fa0

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to form two sinusoidal signals shifted from one another by 90 from one sinusoidal signal from the output of amplifier 30. Amplifier 30 is summing and is designed to sum the signals of setpoint 31 of copying speed and the signal from comparing element 7.

The copying speed setting device 31 sets the initial bypass speed of the contour of the template 12. When the load on the cutting tool is changed

5 the signal changes from element 7

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compare. As the load increases, the signal at the output of the amplifier 30 decreases and the bypass rate of the pattern 12 circuit decreases accordingly, and as the load decreases, the bypass speed increases.

The copying speed setter 31 performs the function of a manual speed controller with an automatic probe bypassing the contour 13 of the template 12, changing the amplitude of the sinusoidal signal by turning the knob 58 at the first input of the amplifier 30.

An increase in amplitude causes an increase in the speed of bypassing (copying), and a decrease — a decrease in speed; growth bypass. A change in the amplitude of the signal at the output of the amplifiers 30 causes a change in the amplitude of the signals at the first inputs of the phase discriminators 23 and 24. A change in the input signals causes a change in the output signals of the phase discriminators 23 and 24, and therefore a change in speed

drive 10 feeds, i.e. change the speed of bypass probe 13 of the contour of the template

12. Thus, the change in the amplitude of the input signal of the amplifier 30 by turning the knob handle 58

31 copying speeds change copying. The copying speed direction sets the copy sensor 14. Depending on the amount of deviation of the probe 13 from its vertical axis, the copy sensor 14 causes two signals varying in sine and cosine functions. One signal controls the longitudinal feed and the other transverse feed of the copying device 11 through the drive 10.

The signals from the copy sensor 14 are received through amplifiers 21 and

22 on the second inputs of phase discriminators 23 and 24.

A change in the input signals and functions of sine and cosine causes a change in the output voltages of direct current of phase discriminators

23 and 24: on one - according to the law of sine and on the other - according to the law of cosine,

and therefore, the movement of the coordinates of the copier 11 according to these laws. As a result, the contour speed vector is always tangential to this contour, which is required for automatic contour walking.

Thus, the signal from the copying speed setting device 31 determines the bypass speed of the circuit, and the signals from the copy sensor 14 determine the direction of the bypass speed vector.

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All of the above relates to the operation of the copier 11 without the fate of the signal from the comparison element 7, which passes to the second input of the amplifier 30. The effect of this signal on the operation of the copier 11 is the following. When machining part 4, the load on the cutting tool 5 is changed due to the variable machining allowance. A change in the load senses the load sensor 6 and converts it into an electrical signal, a proportional load. This signal is applied to the first input of the comparison element 7, to the second input of which a signal is supplied from the setpoint load device 8 | ki. The load setpoint adjuster 8 sets the signal change range from the load sensor 6, limiting it in terms of

The range of change of the load signal depends on the durability of the cutting tool.

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It appears in the technology for processing parts 4.

Thus, the magnitude of the output signal of the comparison element 7 is proportional to the load on the cutting tool 5, but is limited in amplitude by the load adjuster 8. By entering the input of amplifier 30, this signal is summed with the signal of the setpoint: copy speed 31 so that an increase in the signal causes a decrease in the output signal of the amplifier 30, and a decrease in the signal causes an increase in the output signal. The copy speed setting knob 31 sets a specific constant speed level, against which the load signal automatically changes the copy speed depending on the load on the cutting tool 5. The change in copy speed calls by means of displacement sensors 15, control unit 1 and drive 2 feed rates change the feed rates of the machine 3 in such a way that when the load increases | On the cutting tool 5, the feed speed of the machine 3 decreases, and when the load decreases, it increases, resulting in stabilization load on the cutting tool 5.

The copier 11 together with displacement sensors 15, feed drive 10, copy control unit 9, comparison element 7 and load sensor 8 represent a separate device which is located next to the machine 3 and is connected to it via an electrical connector. Through the connector, the output of the displacement sensors 15 and the output of the load sensor 6 are connected.

As the copier 11 can be used known copier milling machine. The copier 11 has a working table, along the guides of which the neipe and longitudinal and transverse carriages can be neipe. A longitudinal carriage provides movement along the X coordinate. A longitudinal carriage is mounted on the longitudinal carriage, which provides movement along the Y coordinate.

The transverse carriage has a copy sensor 14 with a probe 13, the axis of which is perpendicular to the surface of the table. Longitudinal and transverse

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the carriages are raised above the working surface of the table, on which template 12 is installed;

The carriages are driven through a screw-nut drive with a 10-feed drive. After processing the first part 4, the connector is disconnected and the machine 3 continues the processing of the following parts 4 in the Play mode as

This means that, in order to expand the range of adjustment of the feed speeds of the machine, a copier was inserted containing a copy sensor, as well as a feed drive of the copier, a copy control unit. Motion sensors, X and Y coordinates, mode switch, signal amplifiers, mechanically coupled switching contacts of the mode switch are connected to the sensor outputs; a remanufactured machine with software control, and readout, respectively, X with the at the coordinates, whose inputs are via grams, recorded on the instantaneous tape, the first mechanically connected perrclues- 50 when processing the first part 4, the contiguous contacts of the mode switch holds information about the changes connected to the magnet head of the machine 3 with changes, 5 strokes of recording signals and loads on the cutting tool 5. To calculate the X and Y coordinates through W, this should be borne in mind that this program is suitable for processing subsequent parts 4, subject to the identity of the workpiece blanks and the first inputs of the corresponding batch of parts 4. coordinates of the control unit, to the second

Rotary transformers of the TMM-1B type are used as feedback and displacement sensors. A lime sensor of the RF11-2 milling machine can be used as a copy sensor 14.

As a device for recording a program on a magnetic tape and its: reproduction, the known

inputs of coordinates j (and Y of the control unit are connected to the outputs of the feedback sensors of the coordinates X and Y, the output of the comparison element 25 is connected to the first input of the copy control unit, to the second inputs of which are connected the outputs of the copy sensor, and to the outputs of the copy control unit the drive inputs of the copier feed, the device for recording and playback- 2. The system according to claim 1, distinguished for an RFP-2 milling machine, so that the control unit As the control unit 1, it contains control channels In X and Y, the known two-coordinates are used, each of which contains three amplifiers and a phase discriminator, the first and second inputs of which are connected through the first and second amplifiers, respectively, to the first 40 and second inputs, corresponding to the phase discriminator through the third amplifier is connected to the output of the corresponding coordinate of the control unit 45.

coordinate control panel of the RFP-2 milling machine.

The application of the proposed system allows to obtain optimal cutting modes, which leads to an extension of the range of control of the feed speed of the machine, to a reduction in the machining time of the part and to an increase in the service life of the cutting tool.

Claims (3)

Invention Formula 1 Self-adjusting software control system containing feedback sensors X and Y coordinates, stanchion feed drive, sensor 3. A system according to claim 1, characterized in that the copy control unit contains control channels of the X and Y coordinates, each of which contains three amplifiers and a phase discriminator, as well as a copy speed sensor, a summing amplifier and a phase shifter. 3. The system according to claim 1, characterized in that the copy control unit contains control channels of the X and Y coordinates, each of which contains three amplifiers and a phase discriminator, as well as a copy speed sensor, a summing amplifier and phase shifting loads, load control unit, reference element, tape drive mechanism with drive and magnetic head and control unit, element inputs of the comparison element, the first and second inputs of the sum, are connected to the load cell of the world element, are connected to the load master and load adjuster, outputs the control unit is connected to the corresponding inputs of the feed drive, which is fed with the input of the block and with the output of the copy speed limiters, the inputs of which are connected to the common bus and to the source ten This means that, in order to expand the range of adjustment of the feed speeds of the machine, a copier was inserted containing a copy sensor, as well as a feed drive of the copier, a copy control unit. Motion sensors, X and Y coordinates, mode switch, signal amplifiers and readouts, respectively, X "coordinates, the inputs of which are connected to the magnetic head through the first mechanically connected primary switches of the mode switch, and the outputs of the recording and amplifier amplifiers The X and Y coordinates through the second mechanically connected switching contacts of the mode switch are connected to the outputs of the sensors; the displacement and the first inputs of the corresponding coordinates of the control unit to the second 3. The system according to claim 1, characterized in that the copy control unit contains control channels in X and Y coordinates, each of which contains three amplifiers and a phase discriminator, as well as a copy speed sensor, a summing amplifier and a phase shifter the element, the first and second inputs of the sum, the peace element are connected to the first the element, the first and second inputs of the sum, the peace element are connected to the first the block input and with the output of the copy speed limiter, whose inputs are connected to the common bus and to the the reference voltage point, the output of the summing amplifier is connected to the input of the phase-shifting element, the outputs of which are connected to the inputs of the first control channel amplifiers, the output of each first amplifier is connected to the first input, respectively 1 $ , 130224012 : a phase discriminator, the second input of which through the second amplifier is connected to the corresponding second input of the unit, and the output of the corresponding phase discriminator through the third amplifier is connected to the corresponding output of the unit. fpuz.l  from the date and on the equipment Z Record 50 L Revision 16IPUBA 8 Load kg FIG. five FIG. 6 MI 67 SS 7 Editor L. Gratilllo Compiled by A. Praknikova. Tehred L. Serdyukova Proofreader N. Pojo Order 1215/46 Circulation 864 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, RaushSka nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4