SU847096A1

SU847096A1 - Differential pressure pickup

Info

Publication number: SU847096A1
Application number: SU802868678A
Authority: SU
Inventors: Владислав Иванович Каспирович; Юрий Михайлович Мармышев; Виктор Михайлович Соседкин
Original assignee: Предприятие П/Я А-3487
Priority date: 1980-01-16
Filing date: 1980-01-16
Publication date: 1981-07-15

Description

(54) ДИФФЕРЕНЦИАЛЬНЫЙ ДАТЧИК ДАВЛЕНИЯ(54) DIFFERENTIAL PRESSURE SENSOR

II

Изобретение относитс к контрольно-изMepHTCtHbHofl технике, в частности к датчикам давлени , а также к компенсационным расходоме рам переменного перепада давлени и, может быть использовано дл измерени , с1игнал|изации и регулировани расхода воздуха ц других газов, в том числе взрывоonacHi|x .The invention relates to a control of the MEPHTCtHbHofl technique, in particular pressure sensors, as well as compensating flow rates of variable pressure differential and, can be used to measure, signal and regulate the flow rate of air of other gases, including explosive HI | x.

Известен датчик давлени , содержащий закрепленную в корпусе мембрану с жестким центром, с которой св зано индикаторное микрометрическое устройство со 1.A pressure sensor is known that contains a rigid center membrane fixed in the housing, with which the indicator micrometer device 1 is connected.

Известен дифференциальный датчик даЬлени , I содержащий корпус, установленную в нем эластичную мембрану с жестким центром , упоры ограничени хода жесткого центра , электромагнит с сердечником и индикатор перемещени жесткою центра мембраны 2.A differential pressure sensor is known, I comprising a housing, an elastic membrane with a rigid center installed therein, stops for restricting the movement of the rigid center, an electromagnet with a core, and an indicator for moving the rigid center of the membrane 2.

Недостатком известного устройства вл етс сложность конструкции, а также низка степень взрывозащищенности.A disadvantage of the known device is the complexity of the design, as well as the low degree of explosion protection.

Цель изобретени - упрощение конструкции и обеспечение взрывозащищенности .The purpose of the invention is to simplify the design and ensure explosion protection.

Указанна цель достигаетс тем, что индикатор перемещени жесткого центра мембраны -размещен в осевом отверстии сердечника электромагнита, который размещен снаружи корпуса. Причем корь электромагнита выполнен в виде жесткого центра мембраны, изготовленного из магнитом гкого материала и контактирующего с ограничительными упорами.This goal is achieved by the fact that the indicator for moving the rigid center of the membrane is placed in the axial hole of the core of the electromagnet, which is located outside the housing. Moreover, the electromagnet measles is made in the form of a rigid center of a membrane made of a magnet of a soft material and in contact with restrictive stops.

Устройство содержит корпус 1, крыщку 2, эластичную мембрану 3 с жестким The device comprises a housing 1, a lid 2, an elastic membrane 3 with a rigid

10 центром в виде диска 4 из магнитом гкого материала, например электротехнической стали, упоры 5 в количестве не менее трех, электромагнит 6 силовой компенсации, индикатор 7 перемещени жесткого центра мембраны, который закрепл етс , в осевом 10 by the center in the form of a disk 4 made of a magnet of a soft material, for example, electrical steel, stops 5 in an amount of not less than three, an electromagnet 6 of power compensation, an indicator 7 of moving the rigid center of the membrane, which is fixed, in an axial

15 отверстии сердечника 8 электромагнита, плюсовую полость 9 и минусовую полость 10, с входными штуцерами 11 и 12, электромагниты 13 и 14 индикатора 7. перемещени общим рмом и отдельными сердечниками 15 и 16, диск 17 из магнитом гкого материала кор электромагнита 14.15 holes of electromagnet core 8, plus cavity 9 and minus cavity 10, with inlet nipples 11 and 12, electromagnets 13 and 14 of the indicator 7. movement with a common conductor and individual cores 15 and 16, a disk 17 of a magnet of a soft material of the electromagnet core 14.

Claims

The differential pressure sensor can be used as part of a gas flow meter in a scanning converter mode and operates as follows. Through valves 11 and 12, gas is supplied under pressure into the cavities, plus 9 and minus 10. Minus cavity 10 is formed by membrane 3 and lid 2. Under the action of a force proportional to the pressure drop and effective membrane area, the disk 4 is pressed against the stops 5. Between disk 4 and The housing 1 forms a working gap of minimum size (up to 0.5 mm) through the winding. The force compensation electromagnet 6, which is placed on the cylindrical core of the electromagnet 8, is passed through a linearly increasing current. At the moment when the force of attraction of the disk 4 by the electromagnet 6 exceeds the magnitude of the force acting on the membrane 3 and the disk 4, the latter moves up to the wall of the housing 1, approaching the cylindrical body 15 of the electromagnet 6 and the indicator 7 moving the rigid center of the membrane . The windings of the electromagnets 13 and 14 are connected in series, forming a common point, and connected to the winding with the midpoint of the supply transformer. The output of the motion indicator is the voltage unbalance of the AC current taken from the common and midpoint. With the emergence of a signal at the output of the indicator of the movement of the rigid center of the membrane, the instantaneous value of the linearly increasing current, the value of which is proportional to the measured flow, is stored, and then the subsequent rapid decrease of the current to zero. In so doing, the disk 4 is lowered onto the stops 5, and the measurement cycle is repeated. To eliminate the influence of the weight of the disk 4 and the membrane 3 on the output characteristic of the flow meter, a constant bias current (up to 0.2 mA) is passed through the windings of the electromagnets 13 and 14, creating a corresponding additional force of attraction of the disk 4, the electromagnet 6 force compensation. The electrical zero of the movement indicator of the hard center of the membrane 4 is established by changing the gap between the core 16 and the disk 17. In the case of using a membrane differential pressure sensor to signal a decrease in gas flow through the winding of the electromagnet 6, they are passed. and current pulses with a period of several seconds. The amplitude of the current pulses is proportional to the flow rate and is set by the dial. As the flow rate decreases, the force acting on the membrane decreases accordingly. During the current pulse time, the disk 4 moves upwards, the corresponding pulsed signals appear at the output of the movement indicator of the rigid center of the membrane and at the output of the alarm device. The test results of the prototype show that the sensor can measure pressure drops of up to 6.3 kgf / m and can be used to measure the flow rate of gas (including explosive) in a wide range of flow rates with sufficient accuracy. The conversion error does not exceed 2.5%. The proposed differential pressure transducer makes it possible to extend the measurement limit for pressure drops to 6.3 kgf / m. increase the degree of explosion-proof of the sensor in relation to the measured medium and greatly simplify the design of the device, reduce its dimensions and weight. Invention Differential pressure sensor, comprising a housing, an elastic membrane with a rigid center installed in it, restrictive stops on the housing, an electromagnet with a core and an indicator for moving the rigid center of the membrane, characterized in that, in order to simplify the design and ensure explosion-proof, the indicator moves the rigid center membrane is placed in the axial hole of the core of the electromagnet, which is placed outside the body, and the electromagnet measles is made in the form of a rigid membrane center anes, .magnitom made of soft material and in contact with the limiting stops. Sources of information taken into account during the examination 1. USSR author's certificate No. 320736, cl. G 01 L 7/08, 04/20/70.

2. Electric sensors with power compensation SHG. Differential pressure gauges membrane types DM-H, DM-ER, R zansky TsNNTI, 1970 (prototype).