SU1469502A1 - Device for reproducing spectrum of wide-band vibration - Google Patents

Abstract

The invention relates to a testing technique and can be used in complexes for testing products for the effects of random vibration. The aim of the invention is to simplify the device for reproducing the NIN spectrum of broadband random vibration. The device contains after-

Description

one

The invention relates to a testing technique, in particular to devices for reproducing a wide-band random vibration spectrum, and is intended for use in kits for testing products for the effects of random vibrations.

The purpose of the invention is to simplify the reproduction of the spectrum of a broadband random vibration.

Fig. 1 is a diagram of a device for reproducing a spectrum of broadband random vibration; figure 2 is a variant implementation of the synchronization unit.

The device contains a successively connected noise generator I with a tunable bandpass filter (not shown) at the output, the first adjustable amplifier 2, the multichannel memory block 3, the multichannel switch 4, the multichannel adder 5, the power amplifier 6, the exciter 7 oscillations spectrum analyzer 8, the second adjustable amplifier 9, whose control input is connected to the output of the spectrum analyzer 8, and the output to the inputs of the multichannel memory block 3 through the multichannel switch 4, synchronization block W, for example, a serially connected timer and a programmable logic array (FIG. 2), the output of the synchronization unit is connected to the control inputs of the multichannel switch 4 and the spectrum analyzer 8, and also a multi-position switch 11.

The device works as follows.

The signal from the noise generator 1 is fed through the closed key 1 of the multichain switch 4 to the power amplifier 6 and then to the exciter 7 oscillations. The signal from the output of the driver 7 oscillations is fed to the spectrum analyzer 8, in which the measured and compared with the set. values of the spectrum parameters of the corresponding frequency band, as well as a mismatch signal is generated, arriving at the control input of the first adjustable amplifier 2, which changes the ratio of the gain factor and, thus, corrects the signal level to zero mismatch.

The adjusted narrowband signal is recorded, for example, into the first channel of a multichannel memory block 3 via a multi-position switch 11. Similarly, the signals of the rest components of the working spectrum of frequencies in the 30 (p-1) channel of the memory 3 are recorded. The multi-position switch 11 is manually switched.

After the process of writing to the multichannel memory block 3 is completed, the key 35 1 of the multichannel switch 4 is disconnected and the signals are read from the outputs of the memory block 3 through the multi-channel switch 4 to the multi-channel adder 5 and through the power amplifier 6 to the exciter 7.

When reproducing the spectrum of broadband random vibration, sequential correction of the reproduced spectrum in each frequency band is performed, for which the spectrum analyzer 8 according to commands from the synchronization unit 10 sequentially determines the parameters of the spectrum in each 15 frequency bands. The error signal from the output of the spectrum analyzer 8 is fed to the control input of the second adjustable amplifier 9, the input of which receives a signal from the output of the corrected memory block 3.

Let the first frequency band be first corrected, the corrected signal of this band is recorded in the n-th channel of block 3 of memory 25 (the first cycle of the consecutive spectrum correction). According to the commands from the synchronization unit 10, the multichannel switch 4 is set to the state when the keys 2, 30 2, ..., 2. ,, 3, 4 are closed, and the keys 1,2p, 3, 32, ..., 3c , 4, jj .., "(n open. After the error signal at the output of the spectrum analyzer 8 is compensated for by setting the gain of the second adjustable amplifier 9 and the corrected signal is recorded in the pth channel of the multichannel memory block 3, The bandwidth 40 of the spectrum analyzer, according to the coda, from the synchronization unit 10, is set equal to the second band of the one of the reproduced spectrum, and the multichannel switch is set to the state when the keys 2, ..., ,, 2, 3.4 are closed, and the keys 1, 3, ..., 3.,, 3 " , 4,, ..., 4 ", 4", 2, are open. The corrected spectrum is recorded in the 1st channel of memory block 3.

The spectrum is corrected in the same way in all frequency bands. At the same time, the channel of the memory block intended for recording the corrected narrow-band signal is sequentially acted (p-1) channels of the multichannel memory block 3, c.

While the remaining channels reproduce the wideband random signal.

After the end of the first cycle of the consecutive correction of the spectrum in the (p-1) frequency bands, the second correction cycle begins, which differs from the first correction cycle in the initial state (correction of the 1st frequency range) of the keys of the multichannel switch. Next comes the 3rd, 4th, etc. correction cycles. After the end of the pth spectrum correction cycle, the first cycle is repeated.

Thus, the structure of the multi-channel memory block is variable, and this structure is provided by a certain functional organization of the synchronization unit and the multi-channel switch. The use of a multi-channel memory unit with a variable structure makes it possible to simplify the implementation of the latter, reducing the number of adjustable amplifiers in the device for reproducing a spectrum of wideband random vibration.

Claims (1)

Invention Formula A device for reproducing a broadband random vibration spectrum, containing a series-connected noise generator, a first adjustable amplifier and a multi-position switch, to the outputs of which are connected recording inputs of a multi-channel memory unit, and also series-connected multi-channel adder, power amplifier, oscillator and spectrum analyzer, whose output connected to the control inputs of the first and second adjustable amplifiers, as well as a synchronization unit whose outputs are connected Points to the control inputs of the spectrum analyzer and multi-channel switch, characterized in that, to simplify the device, the playback outputs of the multi-channel memory block through the first group of keys of the multi-channel switch are directly connected to the inputs of the multi-channel adder and from the input of the second adjustable amplifier, the output of which is through the third group of keys 514695026 a multi-channel switch is connected via an additional key: the multi-input of a multi-channel memory unit is written, and the generator output of a channeled switch is combined with the output of a multi-channel adder, ma via additional key: the multichannel switch is combined with the output of the multichannel adder,  GMM governing by the authorities. mnovokana / computator Inputs p / 1M. Alrav / 1  zolgaga / blues base 66 / XK7a & // 7 /// f, l / ffpag / fffJ llfM noAQCou fTp (fm / CKaffU & spec 1roani / 1eo.tora. Thebes. 2