CN2277070Y - Liquid crystal display pressure transmitter - Google Patents
Liquid crystal display pressure transmitter Download PDFInfo
- Publication number
- CN2277070Y CN2277070Y CN 95222598 CN95222598U CN2277070Y CN 2277070 Y CN2277070 Y CN 2277070Y CN 95222598 CN95222598 CN 95222598 CN 95222598 U CN95222598 U CN 95222598U CN 2277070 Y CN2277070 Y CN 2277070Y
- Authority
- CN
- China
- Prior art keywords
- liquid crystal
- crystal display
- circuit
- signal
- amplifier
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Abstract
The utility model discloses a liquid crystal display pressure transmitter used for measuring pipeline pressure. The utility model comprises a casing part, a circuit part installed in the casing, and a liquid crystal display circuit connected with the circuit part. The circuit part comprises a constant current source, a sensitive element, an auxiliary amplifier, a signal amplifier, an electric current voltage converter and a nonlinear correction circuit. The pressure of the measured pipeline is converted into a voltage signal by the sensitive element, and the voltage signal is amplified by the auxiliary amplifier and the signal amplifier and then is converted into a current signal by the electric current voltage converter to be input into the liquid crystal display circuit. The constant current source is used for providing a constant current and all levels of reference voltages. The utility model has the advantages of small volume, visual display and sensitive response.
Description
The utility model relates to a kind of instrument and meter for automation, particularly a kind of liquid crystal display pressure unit of measuring channel pressure.
The indicating gauge of pressure unit in the past is to adopt 100% average scale indicating gauge, and its sensitive element adopts the diffuse si sensitive element, exists volume big, and pressure shows not shortcoming intuitively.
The object of the present invention is to provide a kind of pressure unit that adopts intuitive display and the little liquid crystal display displays of volume to measure numerical value; The utility model display format adopts 3 1/2 bit digital to show, be that maximum displayed value is 1999, minimum displayed value is-1999, the numeral that specifically is meant most significant digit in maximum displayed value is 1 (making molecule), top digit is 2 (making denominator) during full scale, so most significant digit is subluxation, and note does 1/2, all the other 3 is integer-bit, so claim 3 1/2.
The liquid crystal display pressure unit that a further object of the present invention is to provide a kind of and is quick on the draw, precision is high.
For the utility model that achieves the above object is taked following technical measures:
The display of liquid crystal display pressure unit of the present utility model adopts LCD, particularly figure place showing to adopt 3 1/2 display; Sensitive element adopts isolated sensor; Specifically composed as follows:
Liquid crystal display pressure unit of the present utility model comprises: housing parts and be contained in circuit part in the housing; Circuit part comprises constant current source, sensitive element, booster amplifier, signal amplifier, current-to-voltage convertor, non-linear correction circuit; Described constant current source connects sensitive element, thinks that sensitive element provides steady current and reference voltage at different levels;
It is characterized in that: described circuit part also comprises a liquid crystal display circuit;
Described sensitive element is converted to voltage signal with the pressure of institute's survey pipeline, and after booster amplifier, signal amplifier amplified, the one tunnel was converted to current signal through current-to-voltage convertor, and another road signal is input to described liquid crystal display circuit; The non-linear correction circuit will be through the signal feedback after amplifying to described sensitive element.
Described liquid crystal display pressure unit is characterized in that, it is the integrated circuit of L7136CM44 that described liquid crystal display circuit adopts model, and it comprises A/D change-over circuit and 3 1/2 LCD; 3 1/2 LCD comprise a liquid crystal display drive circuit and a LCD panel;
Described A/D change-over circuit is deposited electric capacity etc. by the external reference voltage of described integrated circuit L7136CM44, clock oscillation circuit, integrating circuit, input voltage, reference voltage; Shows signal is by the anodal D of liquid crystal display signal
+And negative pole D_ end input; Described liquid crystal display drive circuit is connected the pin of integrated circuit L7136CM44 bottom; LCD panel adopts 3 1/2 N273 μ F circuit, and the respective pin of described LCD panel and liquid crystal display drive circuit interconnects, wherein: a
1～g
1Be units section drive signal, a
2～g
2Be tens section drive signal, a
3～g
3Be hundred figure place section drive signals, AB4 is a thousands digit section drive signal; Dp
1～dp
3Be respectively right first, second, third radix point that rise.
Described liquid crystal display pressure unit, it is characterized in that described sensitive element is an isolated sensor, adopt the diffuse si sensitive element, diffusion has a Wheatstone bridge on the monocrystalline silicon diaphragm, is sent on the sensitive element by the silicone oil of measuring pressure by an isolation diaphragm and filling.
Described liquid crystal display pressure unit is characterized in that, described non-linear correction circuit is connected between the output terminal and sensitive element of described booster amplifier.
Described liquid crystal display pressure unit is characterized in that: described constant current source mainly comprises a triode, an operational amplifier and stabilivolt; The emitter output dc voltage of described triode is for operational amplifier, and the output terminal of operational amplifier output steady current is given described sensitive element, and the stable benchmark voltage that provide at different levels are provided described stabilivolt;
Described booster amplifier is a differential amplifier, comprise two operational amplifiers, it is by the power supply of the triode in the described constant current source, and the positive input terminal of described operational amplifier connects the signal end of described sensitive element, and the output signal of this operational amplifier is passed to the signal amplifier of next stage;
Signal amplifier is an output amplifier, and it is made up of an operational amplifier, and this operational amplifier receives the output signal of the operational amplifier in the described booster amplifier, transports to current-to-voltage converting circuit after amplifying;
Described current-to-voltage convertor mainly is made up of a triode, and the output signal of the operational amplifier in the signal amplifier is added to the base stage of triode, produces the direct current signal of 4～20mA after amplifying; For liquid crystal display.
Described liquid crystal display pressure unit is characterized in that, it is the integrated circuit of LM224 that described 4 operational amplifiers adopt model.
Liquid crystal display pressure unit of the present utility model with the liquid crystal display pressure unit compare and have following effect:
Because liquid crystal display pressure unit of the present utility model adopts liquid crystal display displays institute measuring pressure numerical value, display format adopts 3 1/2 demonstrations, sensitive element adopts the diffuse si sensitive element, so have intuitive display, volume is little, reading does not have personal error and sensitive characteristics;
Liquid crystal display pressure unit precision height of the present utility model, good stability aspect electrical property, its full accuracy can reach 0.1%, is generally 0.2%～0.5%; Stability: year drift value be full scale output ± 0.1%; The temperature drift amount is little, and in 0～70 ℃ of scope, temperature drift is less than 0.2% of full scale output, and maximum is no more than ± and 0.75%.
Wide range of the present utility model is regulated, and zero point, maximum can migrate to 80% of maximum rated range, and full scale can move 500% in maximum rated range ability.
The utility model also is easy to carry, and is convenient by dress, can adopt directly to reach indirect mode by dress, can save pressure guiding pipe.
Reaching embodiment in conjunction with the accompanying drawings is described as follows characteristics of the present utility model:
Description of drawings:
Fig. 1: the profile synoptic diagram of liquid crystal display pressure unit of the present utility model;
Fig. 2: the circuit block diagram of liquid crystal display pressure unit embodiment of the present utility model;
Fig. 3: the circuit theory diagrams of liquid crystal display pressure unit embodiment of the present utility model;
Fig. 4: the circuit diagram of the liquid-crystal display section of the utility model embodiment.
Reaching embodiment in conjunction with the accompanying drawings is described as follows the characteristics of liquid crystal display pressure unit of the present utility model:
As shown in Figure 1, liquid crystal display pressure unit of the present utility model comprises: housing parts 1 and be contained in circuit part 2 in the housing 1; The upper face of housing parts 1 is provided with the LCD 3 that is connected with circuit 2;
As shown in Figure 2, it is the circuit block diagram of liquid crystal display pressure unit embodiment of the present utility model; Circuit part 2 comprises constant current source 28, sensitive element 21, booster amplifier 22, signal amplifier 23, current-to-voltage convertor 24, non-linear correction circuit 27 and liquid crystal display circuit 25;
As shown in Figure 3, it is the circuit theory diagrams of liquid crystal display pressure unit most preferred embodiment of the present utility model; Wherein:
Constant current source 28 mainly comprises triode 282, operational amplifier 281 and stabilivolt 283; The emitter output 11V DC voltage of triode 282 is for operational amplifier 281, and sensitive element 21 is given in the output terminal of operational amplifier 281 output 1.5MA constant current, and the stable benchmark voltage that provide at different levels are provided stabilivolt 283.
Current-to-voltage convertor mainly is made up of a triode 241, and the output signal of operational amplifier 222 is added to the base stage of triode 241, produces the direct current signal of 4～20mA after amplifying; It is the integrated circuit of IM224 that above-mentioned 4 operational amplifiers 281,221,222,231 adopt model.
As shown in Figure 4, it is the circuit diagram of the liquid crystal display circuit of the utility model embodiment; Liquid crystal display circuit 25 comprises A/D change-over circuit 251 and 3 1/2 LCD 252; This part employing model is the integrated circuit of L7136CM44 in the present embodiment, from the V of operational amplifier 221
+End output is about the burning voltage of 9V, and as the power supply positive pole of liquid crystal display circuit 25, a, b, c are illusory ground among the figure, with respect to power supply negative pole V_ the pressure drop of one 0.3V are arranged, and stablize without interruption, and pretending is the anodal D of liquid crystal display signal
+, between power cathode V_ and signal negative pole D_, connect a diode 253.
A/D change-over circuit 251 is deposited electric capacity etc. by the external reference voltage of integrated circuit L7136CM44, clock oscillation circuit, integrating circuit, input voltage, reference voltage; Shows signal is by the anodal D of liquid crystal display signal
+And negative pole D_ end input; 3 1/2 LCD 252 comprise a liquid crystal display drive circuit 2521 and LCD panel 2522, and liquid crystal display drive circuit 2521 is connected the pin part of integrated circuit L7136CM44 bottom; LCD panel 2522 adopts 3 1/2 N273 μ F circuit, and the respective pin of described LCD panel and liquid crystal display drive circuit interconnects, wherein: a
1～g
1Be units section drive signal, a
2～g
2Be tens section drive signal, a
3～g
3Be hundred figure place section drive signals, AB4 is a thousands digit section drive signal; Dp
1～dp
3Be respectively right first, second, third radix point that rise.CN1 (V among the figure
+, V_, D
+, D_) with Fig. 3 electrical schematic diagram in signal wire V
+, V_, D
+, D_ connects.
Claims (6)
1, a kind of liquid crystal display pressure unit comprises: housing parts and be contained in circuit part in the housing;
Described circuit part comprises constant current source, sensitive element, booster amplifier, signal amplifier, current-to-voltage convertor, non-linear correction circuit; Described constant current source connects sensitive element, thinks that sensitive element provides steady current and reference voltage at different levels;
It is characterized in that: described circuit part also comprises a liquid crystal display circuit;
The output terminal of described sensitive element connects the input end of booster amplifier, and the output terminal of booster amplifier connects the input end of described signal amplifier, and the output terminal of signal amplifier connects the input end of liquid crystal display circuit and current-to-voltage convertor respectively; The input end of described non-linear correction circuit and output terminal connect the output terminal and the sensitive element of booster amplifier respectively.
2, liquid crystal display pressure unit according to claim 1 is characterized in that, it is the integrated circuit of L7136CM44 that described liquid crystal display circuit adopts model, and it comprises A/D change-over circuit and 3 1/2 liquid crystal display circuits; 3 1/2 liquid crystal display circuits comprise a liquid crystal display drive circuit and a LCD panel;
Described A/D change-over circuit is deposited electric capacity etc. by the external reference voltage of described integrated circuit L7136CM44, clock oscillation circuit, integrating circuit, input voltage, reference voltage; Shows signal is by the anodal D of liquid crystal display signal
+And negative pole D_ end input; Described liquid crystal display drive circuit is connected the pin of integrated circuit L7136CM44 bottom; LCD panel adopts 3 1/2 N273 μ F circuit, and the respective pin of described LCD panel and liquid crystal display drive circuit interconnects, wherein: a
1～g
1Be units section drive signal, a
2～g
2Be tens section drive signal, a
3～g
3Be hundred figure place section drive signals, AB4 is a thousands digit section drive signal; Dp
1～dp
3Be respectively right first, second, third radix point that rise.
3, liquid crystal display pressure unit according to claim 1, it is characterized in that, described sensitive element is an isolated sensor, adopt the diffuse si sensitive element, diffusion has a Wheatstone bridge on the monocrystalline silicon diaphragm, is sent on the sensitive element by the silicone oil of measuring pressure by an isolation diaphragm and filling.
4, liquid crystal display pressure unit according to claim 1 is characterized in that, described non-linear correction circuit is connected between the output terminal and sensitive element of described booster amplifier.
5, liquid crystal display pressure unit according to claim 1 is characterized in that:
Described constant current source mainly comprises a triode, an operational amplifier and stabilivolt; The emitter output dc voltage of described triode is for operational amplifier, and the output terminal of operational amplifier output steady current is given described sensitive element, and the stable benchmark voltage that provide at different levels are provided described stabilivolt;
Described booster amplifier is a differential amplifier, comprise two operational amplifiers, it is by the power supply of the triode in the described constant current source, and the positive input terminal of described operational amplifier connects the signal end of described sensitive element, and the output signal of this operational amplifier is passed to the signal amplifier of next stage;
Signal amplifier is an output amplifier, and it is made up of an operational amplifier, and this operational amplifier receives the output signal of the operational amplifier in the described booster amplifier, transports to current-to-voltage converting circuit after amplifying;
Described current-to-voltage convertor mainly is made up of a triode, and the output signal of the operational amplifier in the signal amplifier is added to the base stage of triode, produces the direct current signal of 4～20mA after amplifying; For liquid crystal display.
6, liquid crystal display pressure unit according to claim 5 is characterized in that, it is the integrated circuit of LM224 that described 4 operational amplifiers adopt model.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 95222598 CN2277070Y (en) | 1995-09-14 | 1995-09-14 | Liquid crystal display pressure transmitter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 95222598 CN2277070Y (en) | 1995-09-14 | 1995-09-14 | Liquid crystal display pressure transmitter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2277070Y true CN2277070Y (en) | 1998-03-25 |
Family
ID=33869891
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 95222598 Expired - Fee Related CN2277070Y (en) | 1995-09-14 | 1995-09-14 | Liquid crystal display pressure transmitter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2277070Y (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103323153A (en) * | 2013-06-27 | 2013-09-25 | 无锡信大气象传感网科技有限公司 | Piezoresistive pressure transmitter |
| CN113834601A (en) * | 2021-11-29 | 2021-12-24 | 广州市美烨电子科技有限公司 | Pressure display transmitter and control method thereof |
| CN114166385A (en) * | 2021-12-03 | 2022-03-11 | 上海洛丁森工业自动化设备有限公司 | Transmitter circuit device, pressure transmitter and application thereof and pressure instrument |
-
1995
- 1995-09-14 CN CN 95222598 patent/CN2277070Y/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103323153A (en) * | 2013-06-27 | 2013-09-25 | 无锡信大气象传感网科技有限公司 | Piezoresistive pressure transmitter |
| CN103323153B (en) * | 2013-06-27 | 2015-10-21 | 无锡信大气象传感网科技有限公司 | A kind of piezoresistive pressure transmitter |
| CN113834601A (en) * | 2021-11-29 | 2021-12-24 | 广州市美烨电子科技有限公司 | Pressure display transmitter and control method thereof |
| CN114166385A (en) * | 2021-12-03 | 2022-03-11 | 上海洛丁森工业自动化设备有限公司 | Transmitter circuit device, pressure transmitter and application thereof and pressure instrument |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101446193B (en) | Device and method for detecting coal seam gas pressure and coal wall stress | |
| CN101467013A (en) | Method and apparatus for measuring temperature | |
| CN2277070Y (en) | Liquid crystal display pressure transmitter | |
| CN201653867U (en) | Measuring system of low velocity non-linear seepage parameter | |
| CN205607567U (en) | Multrirange array pressure sensing chip and check out test set thereof | |
| CN102768096B (en) | Pressure measuring device with temperature drift compensation function | |
| CN204314388U (en) | A kind of program controlled high precision resistance measuring instrument based on analog to digital converter | |
| CN104090165A (en) | Silicon nano sensing array giant piezoresistive coefficient measuring system and four-point bending force-applying device | |
| CN206740279U (en) | A kind of pressure measurement circuitry | |
| CN2849730Y (en) | Small signal measurer | |
| CN1224154A (en) | Ceramic thick film resistor pressure transducer | |
| CN204101634U (en) | The huge piezoresistance coefficient measuring system of silicon nanosensor array and four-point bending force application apparatus | |
| CN2148955Y (en) | Strain pressure transducer | |
| CN2645064Y (en) | Out pushing type digital wellhead pressure meter | |
| CN2831063Y (en) | High precision temp change module | |
| JP2540147Y2 (en) | Sensor correction device | |
| CN2416498Y (en) | Improved load measuring gauge | |
| CN2334025Y (en) | Jack overload running performance detecting device | |
| CN202485857U (en) | Digital display pressure gauge | |
| CN212479197U (en) | Oil well multi-parameter measuring device | |
| CN2145374Y (en) | Digital anti-shake pressure gauge | |
| CN220649354U (en) | Symmetrical constant current excitation circuit for strain measurement | |
| CN2349549Y (en) | Liquid flow tester | |
| CN2166435Y (en) | Head loss measuring apparatus for filter chamber | |
| CN2624201Y (en) | Cavityless pressure transducer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |