SU1012201A1 - Adaptive control system for grinding machine - Google Patents

Description

The invention relates to grinding machine control systems and can be used in machine tool construction, in particular, to control mortise grinding.

A grinding machine control system is known, which contains a displacement transducer, a level adjuster, a memory device, a switch and two comparators, the first inputs of which are connected to the output of the displacement transducer and the second respectively to the level adjuster and to you of the switch. In order to improve reliability and accuracy of correction, the CKia6 system is sequentially connected by a di (|) activating link with two outputs and a zero-body, and the displacement transducer is equipped with two additional outputs, one of which is directly and the second is connected to a switch through a differentiating link and null organ. , the second output of the differential link of its link is connected to the switch. The advantage of the system under consideration is that it contains only one primary transducer (allowance sensor), which greatly simplifies its circuit, increases the reliability of operation and accuracy of correction. In the system, the level of the grooming comparator is adjusted to the extent of the allowance by the memory device as a function of the amount of time the tQ of the grinding wheel is inserted into the product. Thus, a change in the constant time T of the AIDS system is taken into account through a change in the tg insertion time tg at a given value of the actual feed rate V.

The disadvantage of this device is the lack of feed correction for the cutting ability of the grinding wheel and the level of working feed of the slide that changes during operation. This reduces the accuracy and processing performance.

Closest to the present invention is an adaptive control system for a grinding machine, comprising a series-connected product size sensor, a unit comparing); elements and a feed generator connected by a second input to the output of the time interval meter, the first input of which is connected to the second output of the unit comparing elements connected by the second input to the output of the product size sensor, and the third. this output to the third input of the feed generator and to the first input of the actuator, the output of which is connected to the grinding wheel, the input of the size sensor is connected to the product 23.

 The disadvantage of this device is the lack of feed correction with regard to the wear of the grinding wheel and the feed rate, which reduces the accuracy and speed of the system.

5 The purpose of the invention is to improve the accuracy and speed of the system. The goal is achieved by containing a diffrenzator connected by an input to the output of a product size sensor 0 and to the fourth input of the feed generator, and the output to the third input of the unit comparing elements and to the fifth input of the feed generator,. connected output to the fourth

5 input, a block of comparing elements, which is connected to the second input of the actuator by the first output, and to the second input of the interval meter by the fourth output

0 time.

FIG. 1 shows a block diagram of the system; in fig. 2 is a plot of stock removal rates.

5 The block diagram of the system (Fig. 1) contains a sensor 1 of the size of the product, a differentiator 2, a block 3 of comparing elements, a time interval meter k, a feed generator 5, an additional device 6., a grinding wheel 7 and a product 8.

Block 3 compares elements contains zero-bodies 9 and 10 and comparators 1 1 and 12. Block 3 is connected to the first and fourth inputs respectively to the first and second inputs of the comparator 12, the output of which is connected to the first output of block 3. The second input and third output of block 3 are the input and output of the nullorgan 10, respectively. The third input of the unit 3 is the inputs of the zero-organ 9 and the comparator 11, and the second output is the output of the hologram-organ 9, the fourth output the output of the comparator 11.

The time interval meter k comprises a series-connected clock generator 13, a counter 1 and a digital-to-analog converter 15,

the first and second inputs of the meter are the control inputs of the counter l4.

The feed generator 5 comprises a first subtractor 1b, a first storage device (memory) 17 and a second memory unit 18 in series, a second subtractor 19, the first multiplication unit 20, the division unit 21, the third storage unit 22 and the second multiplication unit 23 connected by the second input to the first Subtractor 16, the input of which is connected to the first input of the second reader 19 and the second input of the second charger 18 connected by the output to the second input of the second subtractor 19, and the first input to the first input of the first charger 17, the output of which is connected to the second; input block 21 division.

In the generator 5, the first to the fifth inputs are the first input of the first storage device 17, the second input of the second and the third input of the third multiplication unit 20 and 23, the second input of the third storage device 22, the second input of the first storage device 17, and the input of the first subtractor 16, respectively.

The output of the generator 5 is the output of the second multiplication unit 23.

In the diagram of FIG. 2 denoted by S - pripu to the product; W. - the speed of the working feed caliper; V is the actual feed rate. A: The system works as follows.

When the grinding wheel 7 is supplied to item 8, metal removal begins. At the output of sensor 1, the signal changes, and at the output of differentiator 2, a signal appears that is proportional to the removal rate of the allowance V. Signal V is fed to the inputs of the zero-organ 9 and comparator 11 of block 3 of the comparing elements. The beginning of grinding is fixed by a null organ E which, if activated, permits the passage of pulses from the generator 13 to the counter 14 (in the diagram of Fig. 2 this moment is indicated by volume 1). Then the removal rate of the allowance increases exponentially And

where K - the transfer coefficient of the object (depends mainly on the cutting ability of the circle,

0.5-1);

Vj, - speed of the working feed of the caliper, mm / min; . .

t is the time from the beginning of grinding (from point 1, fig. 2) j s;

T - constant time of the AIDS system, p.

When signal V reaches V2 (vol. 2, fug. 2). Specified by the reference level adjuster (in Fig. 1, the reference levels are not shown to simplify the drawing), the comparator 11 of unit 3 is triggered and gives out pulses into the counter T of the generator 13 "In this case, the counter time s of the grinding wheel 7 into the product B is recorded in the counter and the signal tjj appears at the output of the digital-to-analogue converter 15. In feed generator 5, reference level 8, 0 of comparator 12 is calculated.

Zop -to (V-Vn) M, (2) where V is the current speed of the actual

filing;

VA - the final value of the speed 5 of the actual filing at the final command (set with the unit setting reference levels) ;.

M is a dimensionless scale factor characterizing

the parameters of the AIDS system that are changing during operation (time constant T, transmission coefficient K.,., working speed of support support Vg). M is measured on the previous part processing cycle and recorded in the third storage device 22.

0

The V-V signal comes from the output, the nepdoro of the subtractor 16 to the input of the second multiplication unit 23, to the other inputs of which signals are received from the meter k (tt)) and the memory 22 (M). Thus, at the output of the multiplier 23 with a change in V there will be a time-varying reference level S of the comparator 12. At the same time, a signal is fed to another input of the comparator 12 of block 3

0

S is the current value of the allowance from sensor 1. At to (V -V), the MT is removed at the working feed V (Fig. 2, from t. 2 to t. 3). As soon as the values of S and Sjj are compared, $ comparator 12 is triggered and a command is sent to the executive device of the machine to switch on nursing (Fig. 2, Vol. 3). At the same moment

Claims (1)

ADAPTIVE CONTROL SYSTEM FOR GRINDING MACHINE, containing series-connected product size sensor, unit of comparing elements, generator, feed connected by the second input to the output of the time interval meter, the first input of which is connected to the second output of the unit of comparative elements connected by the second input to the sensor output the size of the product, and the third output to the third input of the feed generator and to the first input of the actuator, the output of which is connected to the grinding * wheel, the sensor input p the size is connected to the product, characterized in that, in order to improve the accuracy and speed of the system, it contains a differentiator connected to the output of the product size sensor and to the fourth input of the feed generator, and the output to the third input of the block of comparative elements and to the fifth input of the generator a feed connected by an output to the fourth input of the block of comparing elements, which is connected by the first output to the input of the actuator, and the fourth output to the second input of the time interval meter. SU „1012201