SU731307A1 - Device for measuring turbomachine blade vibration amplitudes - Google Patents

Description

the code division block is connected to another input of the matrix indicator.

The drawing shows a block diagram of a device for measuring the amplitude of vibrations of turbomachine blades.

The device contains axial 1, root 2, peripheral 3 sensors, shapers 4, 5 and 6 pulses, time interval measurement unit 7, reference frequency unit 8, control unit 9, blade counter 10, matrix indicator AND, which is connected to one of its inputs the output of the counter 10 blades, the first input of which is connected to the first input of the control unit 9 and to the output of the pulse former 6, its input connected to the axial sensor 1. The second input of the counter 10 of the blades is connected to the first input of the time interval measuring unit 7, unit 9 controls the output of the pulse former 5, the input of which is connected to the root sensor 2. The second input of the time interval measurement unit 7 is connected to the output of the Lmpulsov 4 former, its input connected to the periphery: an array sensor 3, the third input is connected to the first output block of 8 reference frequencies, the fourth input - to the output of block 9 of the control. The device is equipped with an additional counter 12 and a kodo dividing unit 13 first connected with its input to the fourth input of the time interval measurement unit 1 and the output of the control unit 9. Wto | ) The input of the code division unit 13 is connected to the output of an additional counter 12, one of the inputs of which is connected to the second output of the reference frequency unit 8, the other input to the first input of the time interval measurement unit 1, to the second input of the control unit 9, to the second counter input 10 blades, to the output of the imaging unit 5 pulses of the root sensor 2, and the third input is connected to the output of the block 7 for measuring time intervals. The output of the code division unit 13 is connected to another input of the matrix indicator 11.

The device works as follows. When the wheel of the turbomachine is rotated, sensors 1, 2 and 3 alternate measuring pulses, which are fed to the corresponding drivers 4, 5 and 6 pulses. The amplitudes and durations of the pulses of the sensors 1, 2 and 3 are fed to the inputs of the time interval measurement unit 7, the additional counter 12 of the control unit 9 and the blade counter 10. At the input of the time measurement unit 7 and the additional counter 12 from the block 8 of the reference frequencies, counting pulses of quartz frequencies fi and f2 are received, respectively. In this case, both measured time intervals are inversely proportional to the speed of rotation of the rotor of the turbomachine. Supply coded values of measured values to inputs

block 13 of dividing the codes, at the output of the latter, we obtain a code proportional to the instantaneous position of the blade in its oscillatory motion and independent of the speed of rotation of the rotor of the turbomachine. According to

a code on one of the horizontal control psn of the matrix indicator 11 is a write pulse. At the same time, one of the vertical control levels corresponding to the number of the blade under investigation, from the exit

counter 10 blades also comes a boost

records At the point of intersection of the control of the matrix indicator 11, a point lights up. With a sufficient accumulation time (measurement), on the matrix indicator 11, luminous segments consisting of individual points are observed. The number of these points (the length of each cut-off) is proportional to the amplitude of oscillation of the blade. Synchronization of the entire device; performed using a block

9 management, ..

For statistical processing of the measurement information and the output of the block dividing code can be connected to a digital computer.

The presence in this device of an additional counter and a block dividing unit allows measuring the amplitudes of blade vibrations in a wide frequency range with high accuracy.

Claims (1)

Invention Formula An apparatus for measuring vibration amplitudes of turbine blades, comprising an axial, Koryovoy and peripheral sensors, pulse shapers, measuring unit shremenshlh intervals, block of reference frequencies, control unit, blade counter, matrix indicator, which one of its inputs is connected to the output of the blade counter, the first input of which is connected to the first input of the control unit and to the output of the ramizer impulses connected with an axial sensor with the input, the second input of the blade counter is connected to the first input of the time interval measuring unit, the second input of the control unit B and the output of the pulse former The input of which is connected to the root sensor, the second input of the time interval measuring unit is connected to the output of the shvfflylcoB shaper, the input of its own connected to the peripheral sensor, the third input is connected to the first output of the reference frequency block, the quarter input is to the output of the control unit, characterized in that With the purpose of improving the accuracy of measurements, it is equipped with an additional counter and a block dividing unit connected by its first input to the fourth input of the time measurement unit and the output of the control unit, the second the stroke - with the output of the additional counter, one of the inputs of which is connected to the second output of the reference frequency block, the other input to the first input of the time interval measuring unit, to the second input 7 6 of the control unit, to the second input of the blade counter, to the output of the driver of the quadrnero sensor pulses , and the third input is connected to the output of the time interval measurement unit, and the output of the dividing code is connected to another input of the matrix indicator. Sources of information taken into account in the examination 1. USSR author's certificate number 463v72. cl. 6 01 H 11/00, 1970 (prototype).