SU1499383A1 - Device for determining volumes of system maintenance - Google Patents

Abstract

The invention relates to specialized computing devices and can be used in the design and operation of complex systems for solving maintenance planning tasks. The purpose of the invention is to improve the accuracy of determining the volume of maintenance of the system by accounting for the costs of operating and maintaining the system. The device contains a sensor 1 time, block 2 input information, block 3 delay, a group of elements And 4, blocks 5 ₁ ... 5 _N nonlinearity, switches 6-8, elements OR 9 and 10, counters 11 and 12, integrator 13, block 14 divisions, adders 15 and 16, comparison unit 17, multiplication unit 18, decoder 19, recorder 20 and AND 21 element. The device improves the reliability and validity of the decisions made on the organization of maintenance of complex systems. 2 Il.

Description

00 00

149

The invention relates to specialized computing devices and can be used in determining the parameters of the maintenance of systems whose subsystems are combined by a single operation process and are only brought to service at fixed, predetermined time intervals, in particular, such systems are For example, automated technological lines, complex radio-electronic complexes, etc.

The purpose of the invention is to improve the accuracy of determining the volume of maintenance of the system by taking into account the costs of operation and maintenance of the system.

The average unit cost of operating a system is one of the most general indicators of the quality of system operation.

With ZlC ;,

(1) 25

where C J is the average unit cost of operating the nth subsystem (unit, unit) of the system being analyzed (they can be calculated in rubles, kilowatts, and hours per unit of time, and.); n is the number of subsystems.

For each subsystem, the value of C is determined from the ratio

i

le duration cJ lU Ct.) 0, - 9 (h);

- costs (in absolute units) for the maintenance of the subsystem

From (2) it follows that the value of C- can also be represented as

with,

(3)

For systems whose subsystems are united by a single operation process, for the convenience of organizing maintenance, a certain periodicity of the maintenance of the system as a whole is set. The many possible maintenance periods determine the many types of services, for example: daily, monthly, and so on. Therefore, the period tj can take only one of the possible values, depending on the adopted for the entire system of regulation of the types of maintenance:

.Tt,

j 1

where I is the number (TYPES of servicing the subsystem;

1, if the i-subsystem is serviced in the j-rM form of technical

“: IJ

system maintenance; s

Oh, otherwise; one;

7 (J

WITH;

with t Mo :) + M ;-) 4- Sz; .

:

40

de S - costs per unit of time for. operation of the subsystem in working condition; ((;) - mean time without failure

operation of the subsystem on the inter., shaft duration,, T,

, (G, -) p. (T) dt,

about

 Where P; (t) is the subsystem reliability function;

- the period of technical servicing of the subsystem;

-the cost per unit time just (repair) subsystems;

ju; C o; - average time just subsystems in an inoperable state on interval 50

e;

i;

55

T. - period of j-ro service.

Accordingly, the average unit operating costs of the subsystem can take one of the possible values depending on the selected frequency and maintenance:

with; Z.ij-c, (Tp.

For systems with regulated services, the main task is to determine the amount of service for each type, i.e. composition serviced in each type of subsystems. Its solution is to assign the maintenance operations of each subsystem to one or another type of maintenance of the system as a whole, i.e. determining for each subsystem one of the I possible t-periods of maintenance. With

This should strive to minimize the cost of operating the system. Since these costs are expressed by the relation (1), then for a system with independently functioning subsystems, the global minimum of value C will be achieved with minima Cj. This means that the solution of the problem of determining the volumes of the technical state of the system maintenance consists in classifying the maintenance operations of each subsystem as the type of maintenance at which the average unit cost of operating the subsystems is minimal. The operation of the proposed device is based on such an algorithm.

FIG. 1 shows a block diagram of the device; Fig. 2 is a block diagram of a comparison block.

The device contains a sensor 1 time, block 2 input information, block 3 delays, a group of elements And 4, blocks 5, -5 "nonlinearity, switches 6-8, elements OR 9 and 10, counters 11 and 12, integrator 13, block 14 divisions, adders 15 and 16, comparison unit 17, multiplication unit 18, decoder 19, recorder 20 and AND element 2t,

Comparison unit 17 consists of memory element 22, AND element 23, memory element 24, second AND element 25, trigger 26, comparison element 27, third 28 and fourth And elements 29, delay element 30 and one-shot 31,

Time sensor 1 is co. b) a block of permanent memory with a sequential selection of information (for example, a tape recorder) or a voltage generator of complex shape.

Block 2 is a keypad or switch box,.

The device works as follows.

Block 2, through the first group of outputs, sets up blocks 5 that implement the functions P; (t). From the first output of block 2, the maximum size of the first counter 1 1 is set to be equal to the number I of system maintenance. On the second group of outputs of block 2, the values C,;, i i 1, n are set and fed to the information inputs of the switch 6, on the third and fourth groups of block 2 connected to the information

the second 7 and third 8 switches, are set

 -f;

 1, n, respectively,

With the start of operation, the dagger 1 through the first output sets, in order of increasing, the sequence of possible values of T for the maintenance periods of the system. Each value of T, is accompanied by a gating pulse, which appears at the second output of sensor 1, the values of T, pass through the element 4, to the input of the nonlinear conversion unit 5 corresponding to the first of the subsystems of the system under consideration. The values of the function P; (c) for i 1 through the first element OR 9 are sent to the integrator .13 The upper integration limit is determined by the current value of the first output of sensor 1, C by the integrator signal corresponding to (T-) P, (t) dt arrives at

I o the first input of the block 14 division.

The signals corresponding to the values of C., C; for, pass through switches 8, 7, and 6, respectively. The signal corresponding to the value goes to multiplier 18 and multiplies here.

the value of Tj, s; output sensor 1 time. The multiplication result is summed at the second adder 16 with the value of the signal corresponding to it, and is fed to the second input of the division unit 14. A pulse is supplied to the third gate input of the block 14, which accompanies the value T from the second output of the time sensor 1. The duration of its delay in block 3 is equal to niaxf (t4 +

t ,,), (to +

five

0

five

, o -s

+ tj), where t is the time of signal passing through the Nth block of the device. This ensures that there are no spurious signals at the output of block 14. When a pulse appears at the third input of dividing unit 14, the result of dividing the value (Tj + C,;) / is read (Tr, to the first adder 15 through its second input. The first and third inputs of the adder 15 are supplied with signals corresponding to the values and, respectively, i The third input of the adder 15 is inverse, therefore the input of the block 17

Equalization is given a signal corresponding to the value C calculated on the formula (3).

In block 17 it is decided to compare this signal with the value obtained at the previous step, which corresponds to С j (t-), At the first step, the value of C; (t,) is compared with the number that is known to be C / C; . Comparison takes place with the arrival of a gating pulse from the output of element 3. This pulse is additionally delayed compared to the pulse applied to dividing unit 14 by the amount of signal passing through the adder 15, Sequential comparison for j. 2, 3, bc, lasts as long as the values of Cj (T |) decrease with increasing j.

As soon as the inequality C is satisfied for the first time; (Tr C; (Tu.,), At the output of the comparison block 17, there is a pulse. This pulse indicates that the minimum is reached during the maintenance period, equal to 1. The impulse passes at one of the inputs of the recorder 20 and when it appears on the recorder, fixing is carried out, firstly, that decoder output number 19, on which this high potential is present, secondly, the value received at the registrar |) at the previous step T :. . This means that the subsystem number (in this case, the first one) and the corresponding best subsystem of this subsystem are recorded on the recorder -. live about:

If C | (T) decreases to the value of j I-f, then at the 1st step two cases are possible. In the first case, at C, (Ta) C, (TU: I) - the minimum value of C {is reached with a period; Maintenance equal to Tu, from the output of block 17 comparison does not follow. But the overfill pulse at the output of the first counter 11, since its maximum set from block 2 is equal to I. This overflow pulse arrives at the second input of the first element 21, the first input of this element connected to the b code of the comparison block 17 is inverse. Therefore, in the absence of a signal at the output of the block 17, the pulse from the second

the input element And 21 passes to the input of the recorder 20; The recorder records the number of the output of the high potential detector 19 and the current value of the signal from the sensor output 1, t, e, T |,: In the second case, C; ) C; (T ,. Y - the minimum value of C j is reached

0 with a maintenance period of

Ta. ,, An impulse from the output of block 17 goes to the first inverse input of the element 21, prohibiting the passage of an overflow pulse from the counter 11

5 to the registrar. When the pulse from the output of block 17 arrives at the recorder, the maintenance period of the previous step is recorded, t, eo T,. ,,

0 An impulse indicating the end of the procedure for selecting the service period of the first subsystem, which comes either from the output of block 17 or from the output of counter 11, passes

5 through the second element OR 10, the Cutoff pulse sets the first counter 11 to the zero state, the reference voltage setting unit in block 17 returns to its initial state, preparing

0 data elements to the choice of period about-. serving the next subsystem. A cut of this pulse is produced. also restarting the time sensor 1 through its second input and increasing

5 of the contents of the second counter 12 per unit. Accordingly, high potential will now be present at the second of the decoder outputs 1 9 and signals from the first output

0 sensor 1 will pass through

element 4 on the second block 5, which implements the function P (t), the outputs of the elements of the switches 8, 7 and 6 will pass signals corresponding to the values of C ,, j, for

, The cycle of operation of the device is repeated. The bit depth of the second counter; ka 12 is equal to the number of subsystems of p. Therefore, after completing the selection of the maintenance period of the last, nth subsystem at its second, the output of the overflow pulse, which enters time sensor 1 and prohibits the issuance of sequences, expires: .

After completing the procedures for selecting service periods for all subsystems on the recorder 20, record the possible values of the system maintenance periods and subsystem numbers corresponding to each of the specified service periods. Thus, the volumes of the technical survivors of the system were determined.

The comparator unit (FIG 2) operates as follows. At the output of the comparison element 27, the signal appears in the case when the value of the signal at its input, connected to the output of the first adder 15, corresponding to the value (T :), exceeds the value of the signal at the input connected to the memory element 22, - the reference voltage reference function — it contains the value C; (T, j) o At the initial moment of time, the memory elements 22 and 2A record the signal value, which corresponds to a number obviously greater than C. The comparison results are read using a gating pulse supplied from the output of block 3 of the delay per element I 28. If there is a signal at the time of counting the signal at the output of the comparison element 27, the one-shot 31 starts up and forms a square pulse with a duration not less than the pulse duration indicating the overflow of the first counter 11. This condition is necessary for the effective implementation of the prohibition of the passage of the overflow pulse through the element 21 and

Using the gate pulse from the output of the delay unit 3, the value of the signal arriving at the input of the unit 17 is also recorded in the memory element 22. This recording is made through the AND element 29, the delay element 30, and the AND element 25 Due to the presence of the delay element 30, memory is recorded after the next comparison operation. The value recorded in memory element 22 is used in the next step to perform a comparison operation. In the initial state, a high potential is present at the output of the trigger 26, the output of which is connected to the input of the element AND 25. Therefore, the entry in the element 22 of the values of C, (T;) occurs without interference. When a pulse appears at the output of the second element OR 10, indicating that the service period of the next subsystem has been selected, it passes to the input of the trigger 26, changes its state and causes the appearance of a high resolution potential at the input of the AND 23 element. The comparison of the reference value of the signal that obviously exceeds C from element 24 to element 22 through element 23. And the content of element 24 does not change. Thus, block 17 is prepared for the beginning of the selection of the maintenance period for the next subsystem. Trigger 26 returns to the initial state with the first gating pulse c. output block 3 ,,

Thus, the present invention allows to determine the technical maintenance of complex systems by measuring the average unit cost of operation of the equipment, which expands the field of application of the device - it is applicable to solving the problems of organizing maintenance of a wider class of systems for which significant factors determining The effect of operational life is, along with temporal characteristics-1. {and the process of functioning, as well as the expenditure of resources of various kinds; energy, transport, financial human, etc. The task of availability of readiness is a special case of the problem solved by the proposed device. From formulas (2) and (3) it follows that with C; WITH,,.

WITH,; ABOUT

l () + | 1Г, () с, - К | -; - availability factor under ™

system.

The use of the device allows to increase the reliability and validity of the decisions made on the organization of technical maintenance of a large class of complex systems, the subsystems of which are united by a single process to fulfill the target tasks. This allows, in turn, to reduce the costs of operating the systems and increase their reliability.

Claims (1)

Invention Formula A device for determining the volume of technical maintenance of The system contains a time sensor, the first output of which is connected to the first input of the recorder and to the first inputs of a group of elements AND whose output is connected to the first inputs of the corresponding nonlinearity blocks, the outputs of which are connected to the inputs of the first OR element, the output of which through the integrator is connected to the first the input of the dividing unit, the second output of the time sensor is connected to the input of the delay element, the first output of which is connected to the first inputs of the comparison unit and the first counter, the output of which is connected to the first inputs of the And and the second element OR, the output of which is connected to the input of the second counter, to the second inputs of the first counter and comparison unit and to the first input of the time sensor, the output of the comparison unit is connected to the second inputs of the recorder, the second OR element and the output element of which is connected to the third input of the recorder, the first output of the information input unit is connected to the third input of the first counter, the first output of the second counter is connected to the input of the decoder, the outputs of which are connected to the fourth inputs of the recorder and to the second inputs With the signals of the group of elements And, the second output of the information input block is connected to the second input of the time sensor; the outputs of the first group of outputs of the information input block are connected to the second inputs of the corresponding blocks 5 0 0 5 five nonlinearity, characterized by the fact that, in order to improve accuracy, the first, second and third switches, the multiplication unit, the first and second adders, the second group of outputs of the information input block are connected to the information inputs of the first switch, the output of which is connected to the first input of the first adder, the output of which is connected to the third input of the comparison unit, the third group of outputs of the information input unit is connected to the information inputs of the second switch, the output of which is connected to the first input of the second sum the ora, the output of which is connected to the second input of the division unit, the output of which is connected to the second input of the first adder, the fourth group of outputs of the information input unit is connected to the information inputs of the third switch, the output of which is connected to the third input of the first adder and to the first input of the multiplication unit, whose output connected to the second input of the second adder; the first output of the time sensor is connected to the second input of the multiplication unit; the outputs of the decoder are connected to the charging inputs of the first, second, and third computers utatorov, the second output of the second account chyka connected to the third input sen- chikz time, the second output of the delay element is connected to a third input of block dividing. ШЦ1