SU1410070A1 - Device for simulating the parameters of control system of circular grinding machine - Google Patents

Abstract

The invention relates to the field of computer technology and can be applied for the synthesis and computer-aided design of the parameters of a control system of a grinding machine, in particular, control; from computer. The purpose of the invention is to expand the functionality of the device by taking into account the control effect on the actuator. To do this, the first, second, and third voltage dividers, an integrator, an exponential type nonlinearity unit, a multiplication unit, keys, and a summing amplifier are introduced into the device. This device allows analyzing the relationships between the parameters of the control system and the tasks in its processing modes with the physical rt processes arising in the process of cutting the workpiece surface, and also allows you to select the optimal parameters of the control system that provide the specified accuracy of processing. 1 il. WITH/)

Description

The invention relates to the field of advanced technology and can be used for the synthesis and computer-aided design of the parameters of a circular grinder control system, in particular, controlled by a computer.

The purpose of the invention is to improve the functionality of the device by taking into account the control effect on the actuator.

The drawing shows the device.

The device comprises a circular grinding machine 1 with a gearbox 2 and a screw 3 for feeding a grinding nut 4, a workpiece 5, a direct current electric motor 6, a linear sensor 7 and a circular feedback sensor 8, a reference voltage block 9, totalizer 10, a differentiation unit 11, a multiplication unit 12, an exponential type nonlinearity unit 13, an integrator 14, keys 15 and 16, amplifiers 17 and summing amplifier 18, voltage dividers 19-21. A machine 1 with a gearbox 2 and a screw 3 supplying a pedigree headstock 4, the workpiece 5, a DC electric motor 6, a linear sensor 7 and a circular feedback sensor 8 are included in the physical model of the circular grinder 22, the voltage divider 21 and the integrator 14 is an integrating element with a controlled constant integration, designed to generate a signal proportional to the time of the grinding cycle, during which a corresponding change is made to the inhibitory effect of the control system phenomena, for example, changing the feed rate t, of a pshifovnoy grandma .4. Voltage dividers 19 and 20, switch 15 and summing amplifier 18 together form a signal generating unit proportional to the nominal value of the control value, i.e. proportional to the feed rate t of the wheel head 4, I

The device works as follows.

in a way.

The physical model of the grinding machine 1 with the gearbox 2 and the screw 3 for feeding the grinding headstock 4, the linear sensor 7 and the circular sensor 8 for the feedback, as well as the workpiece 5, are real, i.e.

 -.

make up the real part. The DC motor 6 is the actuator of the model and through the gearbox 2 and screw 3 sets the movement of the grinding headstock 4, proportional to the input signal U, coming from the output of the adder 10 through the amplifier 17.

The signal and is generated as follows.

Based on the constant voltage supplied from the reference voltage unit 9, using the third voltage divider 21 and the integrator 14, a signal is generated that is proportional to the grinding cycle time during which the controlled quantity changes, and is fed to the input of the unit 13. On its output generates a signal that corresponds to a linear or exponential law of change of the control action of the control system during the time T of the grinding cycle, i.e. respectively, the signal is (1. G) or the signal is e where ot and oij are coefficients proportional to the constant time, and is fed to the first input of block 12 at the output.

At the same time, on the basis of the direct voltage supplied from the reference voltage unit 9, the signals corresponding to two predetermined nominal supply values t, i.e., are generated using voltage dividers 19 and 20. t const and tf, j, const. When the key 15 is closed, these signals are fed to the input of the amplifier 18, at the output of which a signal is generated (t "+" 2) or when the key is closed 15 the signal is t., 7.

In addition, in the position I of the key 16 to the second input of the adder 10, the second input of the unit 12 is entered; thus, in the position I of the key 16, a signal is generated that arrives at the second input of the adder 10, corresponding to a specified stepwise change in the feed rate t, during the time C of the a and n 5 section, which looks like

t, + t const with tnCT) ((1

tn const

at

where T, is the time at which a step change is made.

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filing t by unlocking the key 15, performed on the control signal from the integrator 14 (not shown).

In position II of the key 15, the second input of the adder 10 receives a signal from multiplication unit 12, in which, based on the signals from amplifier 18 and unit 13, a resultant signal is generated that corresponds to the linear or exponential laws for decreasing the feed rate t, which when closed key 15 has the form

tH (T) (t + t) (1 -A „T)

ppt A / (G. (1

at

or

tnCT) (tn, + t) e with,

where (-ts is the total time of the grinding cycle.

It is also possible the formation of signals at the second input of the adder 10, which have the form

 t,

 const

at

(tn + t.) (1 -ct T) with

i iu,

Bn t const

-i (tl, .t; .. e-

Where. and c are coefficients proportional to the time constant.

Dp this when the key is closed 15 during the cycle time T. c key 16 is in position I, and the signal from amplifier 18, similarly to that described above, is fed to the second input of 1mator 10 day. When the cycle time is G, the control signal from the integrator 14 (not shown) switches the key 16 to position II, Thus, the second input of the adder 10 receives the signal generated in multiplication unit 12 in the same way as described above. As a result, laws (4) and (5) change the feed rate

t ,. during the grinding cycle,

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The actual movement S of the grinding headstock 4 is measured by a linear sensor 7 or indirectly by a circular sensor 8 of rotation of the screw 3 of the grinding headstock 4. To obtain a signal about the actual speed, movement of the grinding headstock 4, the following equation is solved

ten

t (t) o (.5 (€) / O.G (6)

by differentiating in block 11 a signal from a linear

J5 sensor 7 or from a circular sensor. In feedback, depending on the design of the simulated real control system of a circular grinding machine 1. At the output of block 11

20, a signal is generated that is proportional to the current value of the actual speed of movement of the grinding headstock 4 during the time T of the grinding cycle, and is sent to the first input of the adder 10 as the value -t. As a result, at the output of the adder 10, a total signal i is formed, and at the output of the amplifier 17, the signal I, which is fed to the control input of the electric motor 6.

By changing t values

Hi hj

6ts, as well as the coefficients oi. ,, "(,, Ex, included in equations (1) - (5), it is possible to simulate the parameters of the BaJibHoro round grinding system of the machine tool 1.

The signal and the input to the motor 6, which specifies the movement of the grinding wheel 4, is generated based on the signals arriving at the inputs of the adder 10 and proportional to the change in the feed amount t and the actual

d5 of the speed tf of movement of the polished headstock 4. The last signal, in turn, depends both on the characteristics of the gearbox 2 and the screw 3 of the feed of the grinding headstock 4 (for example, rigidity), and on the parameters of the cutting process when machining part 5 (for example, radial cutting force). Thus, the signal depends on the parameters of the cutting process of the part 5.

Consequently, using the device, it is possible to analyze the relationship between the parameters of the control system and the processing modes it sets with

Claims (1)

Claim A device for modeling the parameters of the control system of a circular grinding machine containing a reference voltage unit, a physical model of a circular grinding machine, an adder whose output is connected through an amplifier to the movement input of the actuator of the physical model of a circular grinding machine, the linear velocity output of which is connected to the input of the differentiation unit, the output of which is connected to the first input of the adder, characterized in that, in order to expand functionality through accounting I control its effects on the actuator, it contains the first, second and third voltage dividers, an integrator, an exponential type nonlinearity block, a multiplication unit, a first and second switch and a summing amplifier, the first input of which is connected through the first switch to the output of the first voltage divider, the second input of the summing the amplifier is connected to the output of the second voltage divider, the output of the summing amplifier is connected to the first input of the multiplication unit and through the make contact of the second key is connected to the second input of the adder, the output is third second voltage divider connected to the input of the integrator, whose output is connected to the input of exponent block type nonlinearity output 'which is connected to a second input of multiplier whose output is connected to the break contact of the second switch, the reference voltage unit outputs are connected respectively to the inputs of the voltage dividers.