RU2020585C1 - Device for determining period of technical service of item - Google Patents

Abstract

FIELD: computer technology. SUBSTANCE: device has division units 1 and 4, non-linearity unit 2, subtracter 3, trigger 5, linearly varying voltage generator 6, memory cells 7 and 11, differentiating element 9, comparator 10, switches 9 and 12. Device permits to determine optimal period of technical maintenance of item, which has properties of duty system, and to evaluate coefficient of readiness. EFFECT: improved efficiency of application; widened area of application. 2 dwg

Description

 The invention relates to computer technology, in particular to control devices, and can be used in scientific research and technology, where it is necessary to determine the period of maintenance of products with the properties of duty systems, as well as to determine their readiness to perform target tasks.

 A device containing a time sensor, a nonlinearity block, an integrator, three adders, three multiplication blocks, two division blocks, a delay element, two comparison blocks, a key, an AND element, an OR element [1] is known. It allows you to determine the optimal period of maintenance of the product according to the criterion of the maximum average value of the useful life, and the value of the availability factor is not less than the specified.

 The disadvantages of the device are low speed and a narrow scope, since when determining the time of maintenance, only a period is calculated, i.e. defines a strict strategy for maintenance of duty equipment.

 Also known is a device containing nine multiplication blocks, seven adders, a time sensor, two division blocks, an indicator, two delay elements, a comparator, three keys and a nonlinearity block [2]. It allows you to determine the optimal period of maintenance of the product by the criterion of maximum profitability. The disadvantage of this device is the narrow scope, as it defines a strict strategy for the maintenance of the product and does not take into account the readiness characteristics of duty equipment.

 The closest in technical essence to the invention is a device containing a trigger, a delay element, a memory element, two comparators, two generators of linearly varying voltage, two inverters, two adders, two non-linearity blocks and two multiplication blocks [3]. It allows you to determine the optimal nominal value of the product element, providing the maximum probability that the generalizing output parameter of the product is in the range of acceptable values.

 The disadvantage of this device is the narrow scope, since it does not allow to determine the maximum period of maintenance of the product with the properties of the duty system, for a given value of its availability factor.

 The aim of the invention is to expand the scope of the device by determining the maximum period of maintenance of the product with the properties of the duty system, with a given value of its availability factor.

 Maintenance is one of the forms of control and management of the technical condition of duty equipment and systems, which are quite widespread. Duty devices are single-use or multiple-use devices in which the preparation time for the intended use due to the majority of the preparation operations is minimized in advance and which are transferred to the intended use mode almost instantly.

где Т(Т_о) и

(T₀) - математические ожидания соответственно времени безотказной работы и времени восстановления (нахождения средства в состоянии отказа).To maintain the standby means in working condition, it is periodically subjected to technical maintenance at time intervals T _о , which consists in monitoring the state of the means and in its repair when a malfunction is detected. If the duration of maintenance is much less than its period, i.e. T _obsl > T _o , then we can make the assumption that T _obsl = 0. As an indicator of readiness of the standby means, you can choose the readiness coefficient. In this case, it must be borne in mind that the product is periodically subjected to maintenance:
K _g (T ₀ ) =

where T (T _o ) and

(T ₀ ) - mathematical expectation, respectively, of uptime and recovery time (finding funds in a state of failure).

P(t)dt =

exp[-

(z)dz]dt где Р(t) - вероятность безотказной работы средства;
Λ(z) - изменяющаяся во времени интенсивность отказа средства;
z - переменная интегрирования.The availability factor of the duty equipment is proportional to its reliability and inversely proportional to the period of its maintenance:
K _g (T ₀ ) =

P (t) dt =

exp [-

(z) dz] dt where P (t) is the probability of failure-free operation of the tool;
Λ (z) - time-varying failure rate of the product;
z is the integration variable.

= const, справедливо следующее соотношение:
K_г(T₀) =

1-exp

-

где

- средняя наработка средства на отказ.At the stage of normal operation, when the failure rate is constant over time, Λ = 1 /

= const, the following relation holds:
K _g (T ₀ ) =

1-exp

-

Where

- average time between failures.

The nature of the dependence K _g (T _o ) is shown in FIG. 1.

1-exp

-

T $\genfrac{}{}{0ex}{}{\text{*}}{\text{о}}$ c T_о;

= 0
На фиг. 2 изображена схема устройства.To ensure the maximum availability factor of the on-duty equipment, it is necessary to determine such a period of its maintenance that would ensure the fulfillment of the following ratios:
K $\genfrac{}{}{0ex}{}{\text{*}}{\text{g}}$ = max

1-exp

-

T $\genfrac{}{}{0ex}{}{\text{*}}{\text{about}}$ c T _o ;

= 0
In FIG. 2 shows a diagram of a device.

 The device comprises a first division unit 1, a nonlinearity unit 2, a subtractor 3, a second division unit 4, a trigger 5, a ramp generator 6, a second memory element 7, a second key 8, a differentiating element 9, a comparator 10, a first memory element 11 and a first key 12.

 The device operates as follows.

. С выхода первого блока 1 деления сигнал U₁= T_o/

поступает на вход делителя второго блока 4 деления и на информационный вход блока 2 нелинейности, с выхода которого сигнал U₂ = exp(-T_o)Т) поступает на вход вычитаемого вычитателя 3. На вход уменьшаемого вычитателя 3 постоянно заведен единичный сигнал U_у = 1, поэтому с выхода вычитателя 3 сигнал U₃= [1 - exp[(-To/T)] поступает на вход делимого второго блока 4 деления. С выхода второго блока 4 деления сигнал U₄=

[1-exp(-T_o/

) T_о поступает на информационный вход второго элемента 7 памяти и вход дифференцирующего элемента 9, с выхода которого производная сигнала U₅ = dU₄/dt поступает на вход компаратора 10. Как только в момент времени t = Т_о* сигнал на входе компаратора 10 станет равным или меньше нуля, U₅ ≅ 0, на его выходе появится управляющий сигнал, который поступает на управляющие входы первого 11 и второго 7 элементов памяти и первого 12 и второго 8 ключей. В первом элементе памяти запоминается значение сигнала t = Т_о*, а во втором элементе памяти запоминается соответствующее этому моменту времени значение сигнала U₄=

[1-exp(-T $\genfrac{}{}{0ex}{}{\text{*}}{\text{o}}$ /T)]/T_o, соответствующее максимальной величине коэффициента готовности. На этом работа устройства заканчивается.When the start signal is received from the second input of the device, trigger 5 is transferred to a single state. The signal from the output of the trigger 5 is supplied to the control inputs of the generator 6 of the ramp voltage and the nonlinearity block 2 and at the same time starts them up (synchronously). The ramp generator generates a signal U ₆ = t, which is fed to the input of the divisible first division unit 1 and to the information input of the first memory element 11. Since the first input device to the input of the first divider dividing unit 1 receives a signal U _in =

. From the output of the first block 1 division, the signal U ₁ = T _o /

is fed to the input of the divider of the second division unit 4 and to the information input of the nonlinearity unit 2, the output of which the signal U ₂ = exp (-T _o ) Т) is fed to the input of the subtracted subtractor 3. The unit signal U _у = 1, therefore, from the output of the subtractor 3, the signal U ₃ = [1 - exp [(- To / T)] is fed to the input of the divisible second division block 4. From the output of the second division unit 4, the signal U ₄ =

[1-exp (-T _o /

) T _о goes to the information input of the second memory element 7 and the input of the differentiating element 9, from the output of which the derivative of the signal U ₅ = dU ₄ / dt goes to the input of the comparator 10. As soon as at time t = T _о * the signal at the input of the comparator 10 becomes equal to or less than zero, U ₅ ≅ 0, a control signal appears at its output, which is fed to the control inputs of the first 11 and second 7 memory elements and the first 12 and second 8 keys. The signal t = Т _о * is stored in the first memory element, and the signal value U ₄ = corresponding to this moment of time is stored in the second memory element

[1-exp (-T $\genfrac{}{}{0ex}{}{\text{*}}{\text{o}}$ / T)] / T _o corresponding to the maximum value of the availability factor. This completes the operation of the device.

Claims (1)

 DEVICE FOR DETERMINING THE PRODUCT MAINTENANCE PERIOD, containing a comparator, the output of which is connected to the control inputs of the first memory element and the first key, the output of which is the second output of the device, the first input of which is connected to the trigger input, the output of which is connected to the control inputs of the nonlinearity block and the generator linearly changing voltage, characterized in that, in order to expand the scope of the device for determining the maximum value of the coefficient of availability and articles, the calculator, the first and second memory elements, the second key and the first and second division blocks are introduced into it, the divider input of the first of which is the first input of the device, the output of the first division block is connected to the information input of the nonlinearity block and to the input of the divider of the second division block, the output of which is connected to the input of the differentiating element and the information input of the second memory element, the control input of which is combined with the control input of the first memory element, the output of the second memory element is connected to the second input key input, the output of which is the first output of the device, the second key control input is combined with the first key control input, the information input of which is connected to the output of the first memory element, the input of which is combined with the input of the divisible first division block and connected to the output of the ramp generator , the output of the nonlinearity block is connected to the input of the subtractor, the output of which is connected to the input of the divisible second division block, the output of the differentiating element is connected to the input to Oparator.

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