SU930670A1 - Automatic change-over switch of subranges of multi-treshold devices - Google Patents

Description

I

The invention relates to electrical measuring technique and can be used to create, for example, vibration measuring instruments with automatic selection of measuring limits. . .

A device for automatic selection of measurement limits is known, comprising a comparison circuit, a switching unit made in the form of an annular reversing counter, a control circuit of the switching unit, relays connected to the anodes of the thyristors of the reversible counter.

The device changes the gain of the amplifier-measuring path by switching the contacts of the relays of the reference elements, which is equivalent to changing the limits of measurement.

To provide measurement of signals in a wide dynamic range (VdB and more), the amplification and measurement path must be built

In the form of two or more separate amplifiers with attenuators (discrete sensitivity controls) that enter into it, this allows optimally combining the range of simultaneous analysis of the equipment with the maximum and minimum measured signals. At the same time, in order to reduce the noise levels caused by transients when switching 10 attenuators, it is necessary to observe that one of the sensitivity adjusters is in the extreme (limit) position, and in the other regulator there is a sequential switching of subranges.

A disadvantage of the known device is the impossibility of controlling two sensitivity controllers with the required order of operation.

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The closest to the invention is the automatic switch of subranges of multi-range devices containing a discrete sensitivity controller, a clock generator, comparing devices, a coincidence circuit, keys and switching relays 2. The disadvantage of this automatic switch is the impossibility of using it in measuring and amplifying paths containing several separate amplifiers and attenuators. The purpose of the invention is to expand the dynamic range of instruments with automatic subband switching. The goal is achieved by the fact that the automatic switch subdiapons multi-limit. devices containing the first sensitivity regulator, generator: clock pulses comparing devices whose outputs are connected to the first input of the first sensitivity regulator, elements of coincidence, the corresponding inputs of which are connected to the output of the clock generator, keys and switching relays, the second sensitivity regulator is introduced connected in series with the first bus and the input bus, two reverse shift registers, which are connected to the outputs of the matching elements, and the outputs through the corresponding Consequently, the connected keys and windings of the switching relays are connected to the power bus, as well as the control unit, the inputs of which are connected to the outputs of the respective comparison circuits, and the outputs to the inputs of the corresponding reverse shift registers, and the group of elements AND-NOT the first inputs of the first and The second groups of elements are NOT connected to the output of the respective comparison circuits, the second inputs, respectively, with the first and last bits of the reverse shift registers, and the outputs are connected to the inputs of the corresponding element matches, the first inputs The second group of elements of the NAND is also connected to the outputs of the respective comparison circuits, the second inputs are connected to the outputs of the corresponding elements of the NAND of the first and second groups, the outputs of the indicated elements are connected to the inputs of the corresponding matching elements, while the outputs of the comparison circuits OR connected to the inputs of the match items. The drawing shows a block diagram of an automatic switch. The switch contains discrete regulators 1 and 2 of sensitivity, circuits 3 and 4 of comparison, element 5IL, elements 6-11 AND-NOT, elements 12 and 13 of coincidence, clock generator, unit 15 controls the operation mode of registers, shift registers 1b and 17, keys 18–23, relays, register reset circuit 30, start button 31. The scheme works as follows. When the button 31 is pressed, the circuit 30 generates a signal that causes the shift registers to reset, while the unit is recorded in the last digit of the register 16 and in the first discharge of the register 17, the relay is turned on via keys 20 and 21. The initial position of the units in the register is is the most optimal, since in this case the controllers are in the average working position. The measured signal and ex is supplied to the controllers 1 and 2 and further to the comparison circuits. If the signal is, then unit 15 translates the registers into the unit shift mode to the right, while element 6 blocks the coincidence element 12, and element 9 unlocks the match element 13, and the pulses from the generator arrive at the input of register 17 only and are one in the second bit of register 17 and relay 28 is turned on via key 22. With a further increase in Uj, the level of Uon.MaKC the register from the motor, similarly to that described, connects the remaining relays in turn. Relays 28 and 29 close their contacts, changing the sensitivity of the regulator 2 and changing the voltage, which is equivalent to changing the measurement limits. When the relay is turned on via the key 23, element 13 blocks element 13, which prevents the unit from being copied off from the register if the value of I2 on.wcuKc is the smallest sensitivity of the regulators 1 and 2. In the case lUj ,,. Uon.ALIN lok 15 switches the registers to the information shift mode, to the left, which, if the relay is switched on alternately, increases the sensitivity of the controllers. When the relay is turned on via key 21, element 13 locks with a signal from element 10 and unlocks element 12 with a signal from element 11, while the generator pulses go to register 16. With the further fulfillment of the inequality U | 1) alternately connect the relay through the keys 20-1.8, which leads to an increase in the sensitivity of the controller 1 and a change in the signal. Element 8 excludes the possibility of further register operation if and - iopAlin at the highest sensitivity of the controller 1. When the inequality Uof, is satisfied. “On. The pug of the comparison circuit through the element OR 5 blocks elements 12 and 13 and the pulses from the generator do not arrive at the registers, while such relays remain in the regulators ensuring the fulfillment of the specified inequality. Thus, the application of the invention in measuring equipment allows the range of the measuring path to be extended up to 80 dB for subband values of 10 dB and reduces the noise level by 6 dB. Claims of the invention Automatic switch for multi-range instrument ranges containing a first sensitivity controller, a clock pulse generator comparing devices whose inputs are connected to the output of a clock generator, keys and switching relays that differ in order to expand the dynamic range , the second sensitivity regulator, connected in series with the first and input busbars, two reverse shift registers, whose inputs are connected to the outputs of elements with the outlets, and the outputs through the corresponding series-connected keys and windings of the switching relays to the power bus, as well as the control unit whose inputs are connected to the outputs of the respective comparison circuits, and the outputs to the inputs of the corresponding reverse shift registers and groups elements and NOT, the first inputs of the first and second groups. AND-NOT elements are connected to the output of the respective circuits and, the second inputs are correspondingly with the first and pos; 1dnymi bits of the reverse shift registers, and the outputs are connected to the inputs of the corresponding matching elements, the first inputs of the third group of AND-NOT elements are also connected to the outputs of the corresponding comparison circuits, and the second inputs with the outputs of the corresponding elements AND-NOT of the first and second groups, the outputs of these elements are connected to the inputs of the corresponding elements of the match, while the outputs of the comparison circuits through the element The ent OR are connected to the inputs of the matching elements. Sources of information taken into account in the examination 1. USSR author's certificate number Zbb, cl. H 03 K 17/0, T960. 2. USSR author's certificate number 23239, cl. And 03 K t7 / 00, 28.11.72 (prototype).

Claims (1)

Claim An automatic subrange switch for multi-limit instruments, comprising a first sensitivity regulator, a clock generator, comparing devices whose inputs are connected to the output of a clock generator, switches and switching relays, distinguishing with the fact that, in order to expand the dynamic range, a second controller is introduced into it sensitivity, connected in series with the first and input bus, two reverse shift register, the inputs of which are connected to the outputs of the elements of coincidence, and the outputs through the corresponding series-connected keys and windings of switching relays to the power bus, as well as a control unit whose inputs are connected to the outputs of the respective comparison circuits, and the outputs to the inputs of the corresponding reverse shift registers, and the group of AND-NOT elements, the first the inputs of the first and second groups of elements AND are NOT connected to the output · of the respective comparison circuits, the second inputs are respectively the first and last bits of the reverse shift registers, and the outputs are connected to the inputs of the corresponding elements of the falling, the first inputs of the third group of AND elements are NOT connected to the outputs of the corresponding comparison circuits, and the second inputs to the outputs of the corresponding elements AND ~ NOT of the first and second groups, the outputs of these elements are connected to the inputs of the corresponding coincidence elements, while the outputs of the comparison circuits through the element OR connected to inputs of matching elements.