SU1610330A1 - Apparatus for measuring pressures - Google Patents

Abstract

The invention relates to instrumentation engineering and allows extending the functionality of a device for measuring pressure by generating additional electrical unintegrated temperature and humidity signals. For this, along with a housing, a membrane, a first inductive converter, an alternating voltage generator, a first measuring bridge 20, an amplifier 34, a rectifier 35, an analog-to-digital converter 36, a digital indicator 37 and a control unit 38, the device contains second and third inductive converters , the second 24 and the third 28 measuring bridges and the switch 33. Layers of thermo-deformation and hygro-deformation materials, as well as magnetic material are applied on the membrane. The operation of the temperature and humidity measurement channels is similar to the operation of the pressure measurement channel and is based on the operation of an inductive converter with a variable air gap. The uniformity of the measuring transducers in all channels simplifies the implementation of the device. 2 Il.

Description

inductive converters, second 2-; and the third 28 measuring bridges and a switch 33. Layers of thermo-deformation and hy- gride of eformation materials, as well as magnetic material, are applied on the membrane. Work of temperature and humidity measuring channels

It is similar to the operation of the pressure measurement channel and is based on the operation of an inductive transducer with a variable air gap. The uniformity of the measuring /, converters in all channels simplifies the implementation of the device. 2 Il.

The invention relates to instrument engineering and can be used to measure the pressure of gaseous media under conditions of varying temperature and humidity.

The purpose of the invention is to extend the functionality of the device by generating additional electrical unintegrated temperature and humidity signals.

FIG. 1 shows the structure of the proposed device; in fig. 2 electric circuit device.

The device comprises a housing 1, a membrane 2 with the first 3, second 4 and third 5 layers of magnetic material, thermo-deformation layer 6 and hygro-deformation material layer 7, the first inductive converter consisting of core 8 with winding 9 and terminals 10 and 11, the second inductive a converter consisting of a core 12 with a winding 13 and terminals 10 and 14, a third inductive converter consisting of a core 15 with a winding 16 and cables 10 and 17, a base 18 and a connector 19.

The device also contains a first measuring bridge 20, consisting of a winding 9 of the first inductive converter and resistors 21-23, a second measuring bridge 24, consisting of a winding 13 of the second inductive converter and resistors 25-27, a third measuring bridge 28 consisting of windings 16 of the third inductive converter and resistors 29-31, alternating voltage generator 32, switch 33, alternating voltage amplifier 34, precision rectifier 35, analog-to-digital converter (A1SCH) 36, digital indicator 37 and control unit 38 Yeni. The housing 1 is made in the form of a hollow cylinder with an external thread for installation on the measurement object and has

four interconnected internal cavities with different diameters for sequential installation of connector 19, bases 18 and membranes 2. On the base 18, cores 8, 12 and 15 of inductive converters are fixed. The membrane 2 is made of a non-magnetic material (for example, in the form of a silicon wafer). In the central part of the membrane 2 above the core 8 of the first inductive converter, the first layer 3 of magnetic material is applied. Above the cores 12 and 15 on the membrane 2 in its peripheral part (in the zone of minimum deformations) layers 6 and 7 are deposited, respectively, of thermal deformation and hygroforming materials, which, in turn, are applied to the second 4 and third 5 layers of magnetic material. The membrane 2 at the site of deposition of layers 5 and 7 can have micropores to provide moisture access to the hygro-formation layer 7.

The membrane 2 is fixed on the housing 1, for example, by means of cellulose-cement. The base 18 is made of electrically insulating material and secured in the housing 1, for example, with an adhesive.

The inputs of measuring bridges 20, 24 and 28 are connected to alternating voltage generator 32, the outputs of bridges are connected to the inputs of electronic switch 33, the output of which through amplifier 34, rectifier 35 and A1Sh 36 is connected to digital indicator 37. Peak output of control unit 38 connected to the setup input of the A / D converter 36, the second output - to the control input of the amplifier 34, and the third output - to the control input of the switch 33. The amplifier 34 is made with adjustable gain to obtain the desired slope of the conversion through pressure measurement channels Tempera

tours and humidity / Control unit 38 is made in the form of a timer, forming a sequence of pulses that controls the elements of the device.

The device works in the following way.

In the first measurement cycle, the control unit 38 sets the ADC 36 to the initial state and connects through the switch 33 to the input of the amplifier 34 the measuring diagonal (output) of the first bridge 20, the signal with which is amplified, is normalized in accordance with the accepted scale of pressure measurement is converted into a constant the voltage of the transmitter 35, and then the digital code using the ADC 36 and the pressure information is displayed on the digital indicator 37.

During the second measurement cycle, the control unit 38 sets the A1Sh 36 to the initial state and connects through the switch 33 a measuring diagonal of the second bridge 24 to the input of the amplifier 34. Under the influence of temperature changes, volume deformation of the thermal material layer 6 of the first material occurs, which leads to a change in the gap between layer 4 the magnetic material and the core 12 of the second inductive converter, the signal from which is similar to the previous one is processed in blocks 34, 35 and 36 and the temperature information is displayed on the digital index Katori 37.

In the third measurement cycle, similar to the previous one, the measuring diagonal of the third bridge 28 is connected and the humidity information is displayed on the indicator 37.

Thus, the operation of the temperature measurement channel and the humidity measurement channel is similar to the operation of the pressure measurement channel and is based on the operation of an inductive transducer with a variable air gap. If necessary, the signals can be linearized in the amplifier 34, made as a functional converter with the function selected by the signal of the control unit 38, or in the A / D converter 36 by known methods.

Due to the formation of additional temperature and humidity signals, the functional POSSIBLE-1 devices are expanded. Thanks

103306

The uniformity of the measuring transducers in the pressure, temperature and humidity measurement channels simplifies the design of the device.

0

five

0

five

0

five

0

five

0

five

Claims (1)

Invention Formula A device for measuring pressure, comprising a housing with a membrane and a first inductive transducer for moving a membrane, an alternating voltage generator, a first measuring bridge, an amplifier, a transmitter, an analog-to-digital converter, a digital indicator and a control unit, the first output of which is connected to the installation input of the analog digital converter, the first inductive converter is included in the first measuring bridge, the power diagonal of which is connected to the alternating voltage generator, and An effective diagonal through an amplifier, rectifier, and analog-to-digital converter is connected to a digital indicator, characterized in that, in order to expand its functionality by generating additional electrical, unrelated temperature and humidity signals, it is equipped with second and third inductive converters installed in the housing. , the second and third measuring bridges and a switch, while on a membrane made of non-magnetic material, directly above the first inductive pr the forming, the middle of the membrane a layer of magnetic material over the second and third inductive transducers at the periphery of the membrane in the area of its minimal deformation. The layers are deposited, respectively, layers of thermo-deformation: and hygro-deformation materials, which, in turn, are coated with corresponding layers of magnetic material, with the second and third inductive converters included in the second and third measuring bridges, the diagonals of which are connected to the alternating voltage generator, and the measuring diagonals of the first, second and third measuring bridges are connected to the corresponding inputs of the switch, the output of which is connected to the information input amplifier control input 716103308 which is connected to the second output of the poi o connected to the un.p.n. control unit, the third output of which switch. . J / 3