SU1325540A2 - Device for registering time of engine operation - Google Patents

Abstract

The invention relates to instrument making, namely to means for measuring the total worked time of turbojet engines. The aim of the invention is to improve the noise immunity of the device by turning off the counters during power up and short-term power loss. The device contains a rotation sensor 1, the first element AND 2, the comparison unit 3, the memory block 4, the register 5, the second element AND 6, the block of elements AND 7, counters 8, current source 9, thermo-dependent resistor 10, voltage-to-voltage converter 11 interval, frequency divider 12, pulse generator 13, first pulse shaper 14, NOT 15 element, second pulse shaper 16, temperature sensor 17, third 18 and fourth 19 And elements, first 20 and second 21 dividing elements, first key 22, first restrictive element 23, second key 24, second og anichitelny member 25, the third separator element 26, delay element 27, the third pyuch 28 and power source 29. Introducing elements 20-28 in a device reduces the effect of interference that interferes with its normal operation. 1 il. (L with go sd JV N

Description

The invention relates to instrumentation, namely, devices for determining the total worked time of turbojet engines under various operating conditions, as well as other types of engines, whose overall service life depends on the ambient temperature and rotational speed, and is an improvement of the device according to aut. St. No. 1262547.

The purpose of the invention is to increase the noise immunity of the device by disabling the counters of the device 5a when it is turned on and short-term power loss.

The drawing shows a block diagram of the device.

The device contains a rotation sensor 1, the first element And 2, the comparison unit, made of reversible counters 3 - 3, the memory block, made of triggers 4i-4i, the register 5, the second element And 6, the block of elements And-7, counters 8, a current source 9, a thermo-dependent resistor 10, a voltage-to-time converter 11, a frequency divider 12, a pulse generator 13, a first pulse shaper 14, an HE element 15, a second pulse shaper 16, a temperature sensor 17; third 18 t fourth 19 And elements, first 20 and second 21 separating elements, made on diodes, first key 22, first restricting element 23, made on a resistor, second Yu1yuch 24, second restricting element 25, made on a resistor, third separating element 26 , made on the diode, the delay element 27, made in the form of an RC-chain, the third key 28, the power source 29.

The device works as follows.

The rotational speed is converted by sensor 1 into a frequency signal which is applied to one of the inputs of element 2, to another input of which time interval T produced by converter 11 is applied. Selecting the value of T provides the desired number of pulses transmitted by element 2 to the comparison unit, which rolled out in the form of reversible counters with preliminary recording at the control inputs.

At the outputs of these reversible counters 3- (-3i, a signal appears only when the number of pulses transmitted by the element 2 is reached, the value set at the control inputs of the counters 3i is 3-), and any control can be recorded at their control inputs set point, thereby providing various settings.

The signal from the output of the comparator is fed to the corresponding; and the control inputs of the 4i-4 trigger points, the memory block and

throws them into one state. This information is transmitted to the input of register 5 for storage.

The information in register 5 is updated in each measurement cycle. On the leading edge of the time interval T, outputted by the converter 11, the driver 14 generates a pulse that erases the information stored in the memory memory unit. shaper 16, generating a pulse, which is fed to the control input of the register, allowing overwriting.

The signal from the register through one of the elements And 6, 18 and 19 is fed to the input of the corresponding block 7, allowing the passage of the reference frequency from the generator 13 to the counters 8, and the registration goes only in the counter that corresponds to the mode with the highest setting, since the enable signal with the highest setting, entering the input of all the other previous elements And 6, 18 and 19, prohibits the passage of permission signals with smaller settings.

Correction of registration of engine resource from ambient temperature is determined in the following ways.

In the second integration cycle, the voltage drop across the thermospecific resistor 10 of the sensor 17 is applied to the input of the converter 11. Since the current through this resistor is provided from the stabilized current source 9, this voltage drop depends only on the ambient temperature. Consequently, the time interval T produced by the converter 11 in the second cycle is integrated

Nor, also depends only on temperature.

Thus, the time interval on

the output of the converter is equal to the sum of

(time of the first cycle of integration)

and TK (second integration time) + T.

By choosing the ratio To and T. you can get the desired correction factor. The time That in turn depends on the time interval Tet, produced at the output of the divider frequency 12.

A feature of the device is that the meters are powered with a delay. In the initial state, the keys 24 and 22 are open, the key 22 is closed, the capacitor of the delay element 27 is discharged. When the power source 29 is turned on, the voltage at the output of the delay element 27, which is supplied to it via the separating element 20, reaches a level sufficient to open the key 28.

The control input of the key 22 is supplied with a supply voltage through the separating element 20 and the limiting element 23. The key 22 closes and enables the transfer of power to the counters 8.

At the same time, the voltage through the limiting element (resistor) 25 and the separating element (diode) 21 is fed to the control input key 28, keeping it in the on state and thereby blocking the operation of the key 22. The power supply through the limiting element 25 is also supplied to the control input of the switch 24 and closes its normally open contacts, as a result of which the delay element 27 comes to its initial state and is prepared for operation during intermittent disconnection

power source 29.

Claims (1)

Invention Formula A device for recording the time of the engine operation St. No. 1262547, 0 characterized in that, in order to increase the noise immunity of the device, keys, a delay element, separating and restricting elements are entered into it, the first output of the power source is connected to the input of the first key and to the input of the first separating element, the output of which is connected to the input of the delay element and through the first restrictive element to the control input of the first key, the output of which is connected to the first power inputs of the counters and through the second limiting element to the control input of the second key and to the input a second separating element, the output of which is connected to the control input of the third key, the output of which is connected to the control input of the first key, the second output of the power source is connected to the second power inputs of the counters and the delay element, 0 to the inputs of the second and third keys, the outputs of the second key and the delay element through the third separation element is connected to the control input of the third key. five