SU970149A1 - Pressure converter - Google Patents

Description

(54) PRESSURE TRANSMITTER

The invention relates to instrument engineering and can be used to measure pressure.

Electrical means are known for expanding the upper limit of the measurement, f rhenium of non-electric quantities, for example pressure, for a given nominal value of the inverse transducer {.

Closest to the present invention is a pressure transducer containing a bellows associated with a coil of a magnetoelectric power compensator, a displacement transducer into an electrical signal whose output through a switch is connected to the input of a reverse integrator connected to an analog storage element connected through a current amplifier and a key with compensator coil 2.

However, the known device is characterized by a low accuracy of pressure measurement due to the use of amplitude scaling in it.

Objective 13 of the invention. Improving the accuracy of pressure measurements.

The goal is achieved by the fact that the pressure transmitter

provided with a discrete time scaling device, the output of which is connected to the control inputs to the (1 switch and the key and with the reference element).

Figure 1 shows a pressure transducer; figure 2 - the same, the structural scheme; on fig.Z - temporary chart of his work.

ten

The pressure transducer contains a magnetic system with a permanent magnet 1, a magnetic core 2 and a full HFcSM tip 3. In the gap of the magnetic system there is a coil 4

Claims (2)

15 power x 1 sensation, which is connected to the bottom of the bellows 5. A coil of the coil 4 is rigidly connected to the slit diaphragm 6, on both sides of which are fixed elements of the motion photosensor - LED 7 and photodetector 8. Motion photosensor output is connected to the input of switch 9, outputs O and “5 of which are connected to the direct and ininvial inputs of the reverse integrator 10, respectively. The output of the inverter 10 is connected to the input of the analog storage element 11, which is connected to the input of the current amplifier 12, and the output of the latter through the modulator 13 is connected to the power compensation coil 4. The time scaling device comprises a clock generator 14 and a unit 15 for generating a predetermined relative pulse duration, the outputs of which are connected to the control inputs of the switch 9 and the key 13 and to the memory element 11 (Figs. 1 and 2). The pressure transmitter is as follows. The measured pressure P is converted to the force FX P), - S, where S is the effective area of the bellows. The discrete time scaling device generates the pulses of the control voltage U and U (Fig. 3). the time t the switch 9 and the key 13 are in position a, for a time t, in position (B For time t, the compensating force is zero and the direct input of the integrator 10 is voltage, where K) the displacement transducer conversion factor . The voltage .U is integrated over time t, at the end of which the output voltage of the integrator is and where m is the time constant of the integrator. During the time t /, the inverter input of the integrator 10 receives the voltage Di Gd-K. Since t t, then the% end of the time the output voltage of the integrator and u 0; It is fixed by the memory element 11 and converts with block 12 to current Ij. In the next cycle, for the time t, a voltage proportional to F, i.e. lh P, K, and for the time t is the voltage, j (F ,, + Fj-) K where F BoLoIy Ы ,. 3, - induction, LQ - the length of the turns of the coil. At the end of the cycle, the output time of the integrator is ,, 4 ,, .- b, .- () H. Proceeding from the fact that FK-bobo3.Fx-rbji, lx- | .K. the sensitivity of the pressure transducer does not depend on the conversion factors of the displacement sensor K), the integrator i / f, and the amplifier Q and is determined by the stability of the magnetoelectric transducer and the time scaling factor. The latter is given discretely with any desired accuracy. The advantage of the proposed pressure transmitter as compared to the known one is a higher measurement accuracy, as well as greater reliability and processability of the circuit, which does not require the selection and fitting of the device elements. Claims: Pressure transducer comprising a bellows coupled to a coil of a magnetoelectric power compensator, displacement transducer to an electrical signal, the output of which through a switch is connected to the input of a reversible integrator connected to an analog storage element connected through a current amplifier and a key to the compensator coil characterized in that, in order to increase the accuracy of pressure measurements, it is equipped with a discrete time scaling device, the output of which is connected to a pack Aulus yuschimi switch inputs and switch and memory element. Sources of information taken into account during the examination 1. Y. Skripnik. Improving the accuracy of converting non-electric quantities into electrical ones, -PSU, 1977, 2. USSR author's certificate for application No. 2625822 / 18-10, cl. G 01 L 7/16, 1978. I and At ///// 7 ///////////. // that // and (Tsig.Z FIG. 2