SU474104A1 - Frequency converter signals - Google Patents

Description

stretching p; 1 is the form stress, fig (fig.

2, fi),, st} CVIIIH:; the start of the amplitude comparator 5, to the other input of which the potential is supplied to the driver. By achievement; zero sawtooth; a negative pulse is formed at the output of the amplitude comparator; M1puls, which triggers the 6th bit pulse | 3. Form thunderstorm issues razr. One Mpuls negative polarity (fng. 2.6), I enter Diy to integrator level / through a resistor

3, at the same time, at the output of the integrator, an increasing pploeobaznoe formation is formed.

At the same time, the negative ilgpulse of negative polarity is fed to the input of the key amplifier 24, the output of which is connected to the Gaitian diagonal of tepomosta 28 (Fig. 2, c). Rectangular pulses are removed from the measuring diagonal of the tezomost, the amilitude of which is separated by the imbalance of the tensometry, and the phase is about the limit of the imbalance of the tensomost. These pulses through the isolating transformer 29 are fed to: the input of the scale amplifier 30. The gain factor is determined by the ratio of the resistors 5 / and 32, and when using the potentiometer 33, a positive initial fault is established at the output of the scale amplifier; and: constant-variable mp pulses (Fig. 2, d). In order to tie these pulses to the zero potential, they are fed to the input of a constant level 34, to which the pulses f) of the transmitter 6 are received for synchronization.

At the output of the clamp of a constant r-yr level, pulses are attached to zero potential (Fig. 2, c), as a result of which the following error is excluded: the transducer from the amplifier's drift and low-frequency crosstalk to the connecting wires of the strain gauge.

From the output of the latch 34 of a constant level, pulses are received at the input 23 of the control with a duration of 1 m 1 pulse of the driver 6. Under the influence of these IMIULES, the length of the pulse of the pulses is regulated by law

t

 +

where go is the initial duration of the impulse

with Ux 0;

UH - the initial value of the regulatory and a "p; and - pulse amplitude from teizomost 28;

K is the gain of the amplifier 24.

The frequency of the remapper is determined by the expression:

   - t,

four

charge yes

time constant AND: integrator | ra /;

 - constant vrs

raz da

integrator;

Uo is the amplitude of the discharge (Pulse,

or

(D.4 - E.V

f .V - a

and,

Thus, the frequency of the transducer is p molor ortsiopali to the magnitude of the unbalance of the S.T bridge, i.e., to be measured in its second parameter.

The durability of the pulses of the converter and, therefore, them: the power supply pulses of the strain gauge, measuring frequency and frequency, remains unchanged. Due to this, the average power dissipated on the strain gauge is unchanged.

The shaper of 6 bit pulses and latch 34 1 STANDING level work as follows.

The spark pulse impeller is a self-oscillating multivibrator on transistors 7 and 8, which with the help of transistor 9 and co-operation circuit on diodes 12 and 13 is maintained in a decelerated mode (transistor 7 is open, transistor 8 is closed). At the output of the amplitude comparator 5, a positive potential is maintained, as a result of which, through a resistor 14, the current flows to: the opening transistor 9, which, in turn, maintains the closed state of the transistor 8.

In the case of short-duration triggered amplitude comparator 5, transistor 9 closes and the multivibrator goes over.

Another state (transistor 7 is closed, transistor 8 is open). The capacitor 22 begins to recharge with the core current of the emitter Repeater in the transistor 10. The magnitude of this current and, therefore, the duration

The impulse of the multivibrator is regulated by the base of the transistor 10.

After the discharge of the capacitor 22 to the coolant voltage, the transducer 7 opens, the multivibrator goes to the original

state and is kept in this state until the next trigger of the amperage comiarator 5. The negative pulse from the collector of the transistor // through the resistor 26 is fed to the base of the transistor 25 key

amplifier 24 and opens it. A pulse of amperes is applied to the supply diagonal of the strain bridge 28; with a magnitude of Eg. Pulses with amplitude, progressed unbalance, are input to the input of the large-scale wire. 30 are measured from the measuring diatopali teizomost. From its output, the pulses go to the input of latch 34 of a constant level on the transistor 35. coming through the resistor 37. At the same time, the potential of the base of the transistor 10 is fixed at the level of zero voltage, and the capacitor 39 is charged with the positive voltage of the output of the amplifier 30 and remembers it.

At the moment when a negative pulse arrives at the base of transistor 55 through resistor p 35, it closes, and the pulse from the output of the scale amplifier 30 goes to the base of transistor 10. Pr; and this constant component of the voltage from the scale amplifier's output is multiplied the same voltage on the capacitor 39. Therefore, the base of the transistor 10 receives impulses tied to a zero potential (Fig. 2, (5). This leads to the elimination of the converter's transducer from the D | rafe of the scale amplifier 30 and the focusing on the strain gauge wires P and provided that their change over the duration of a nanometer pulse is much less than the altitude of the useful signal. The pulses from the output of latch S4 of a constant level go to the base of transistor 10, the precursor, its emitter follower. The voltage change on its base changes the current value recharge yes capacitor 22 and, therefore, the duration of the impulse at the output of the driver 6.

Subject invention

A frequency converter of signals, for example, with strain gauges, containing a series-connected integrator, comparator, and discharge pulse former, characterized in that, in order to increase the sensitivity and accuracy of the conversion,

In the output of a ram generator, controlled by the duration of the generated pulses, is connected to the input of a key amplifier connected to one diagonal of the strain gauge, the other diagonal of which is through a transformer, a large-scale amplifier and a clamp of a constant level connected to the control input of the ramp generator bottom impulses.

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