CN2294462Y

CN2294462Y - Radar liquid level gauge

Info

Publication number: CN2294462Y
Application number: CN 97217388
Authority: CN
Inventors: 宗成阁; 王新; 袁业术; 张新潮; 郭隆刚; 王其高
Original assignee: Institute Of Electronic Engineering Technology Harbin University Of Technology; Sinopec Daqing Petrochemical General Plant Instrument Repair Plant; HARBIN WATCH FACTORY
Current assignee: Institute Of Electronic Engineering Technology Harbin University Of Technology; Sinopec Daqing Petrochemical General Plant Instrument Repair Plant; HARBIN WATCH FACTORY
Priority date: 1997-05-14
Filing date: 1997-05-14
Publication date: 1998-10-14
Anticipated expiration: 2007-05-14

Abstract

The utility model relates to a radar liquid level gauge, which is composed of an antenna, a signal emitting and receiving circuit in a casing, an A/D converter, a signal processor, a D/A converter, a smooth filter, a timer circuit, a peripheral circuit, etc., wherein, the antenna is connected with the signal emitting and receiving circuit; the output end of the signal emitting and receiving circuit is connected with the A/D converter and the signal processor in series; one output end of the signal processor is connected to the input end of the signal emitting and receiving circuit after being connected with the D/A converter and the smooth filter in series; the peripheral circuit is respectively connected to the other output end and input end of the signal processor; the two output ends of the timer circuit are respectively connected with the A/D converter, and one of the two output ends of the timer circuit is connected to the D/A converter simultaneously.

Description

Radar level gauge

The utility model relates to a kind of radar level gauge, is used for the level monitoring of liquid, high viscosity fluid and liquid and solid particle mixture storage tank.

Present employed liquid level gauge can be divided into two kinds: a kind of is the contact liquid level gauge, and the contact liquid level gauge has Weighing type liquid level gauge, float type level gauge, servo motor liquid level gauge, photoconduction liquid level gauge etc. again, and their common drawback is to measure corrosive liquids; Another kind is contactless liquid level, and as excusing from death ripple liquid level gauge, its shortcoming is that the excusing from death sensor may be disturbed by steam on the liquid level or mist, so that spurious signal appears, so the medium temperature requirement can not be too high.

The utility model purpose is intended to overcome the deficiency of prior art, and a kind of reasonable in design, simple is provided, and can follow the tracks of and detect the isoparametric radar level gauge of tank level.

The utility model partly is made up of antenna 7, the microwave device of device in housing and electronic circuit etc.Electronic circuit is made up of signal transceiver circuit, A/D transducer 9, signal processor, D/A transducer 18, smoothing filter 19, timer circuit and several parts of peripheral circuit.Antenna 7 directly is connected with the signal transceiver circuit, the output terminal of signal transceiver circuit and A/D transducer 9, signal processor are connected in series, output terminal of signal processor is with after D/A transducer 18, smoothing filter 19 are connected, be connected on the input end of signal transceiver circuit, two output terminals of timer circuit are connected with the A/D transducer respectively, one of them output terminal is connected with the D/A transducer simultaneously, and peripheral circuit is connected on the output terminal and the input end of signal processor respectively.

The signal output part of the microwave voltage controlled oscillator 1 of signal transceiver circuit of the present utility model is connected the input end of directional coupler 2, an output terminal of this directional coupler is connected with circulator 3, another output terminal links to each other with attenuator 4, one end and the frequency mixer 5 of circulator join, the other end links to each other with the antenna 7 that is installed in wet tank 6 tops, the output terminal of attenuator 4 connects another input end of frequency mixer 5, frequency mixer 5 with connect A/D transducer 9 after balanced device 8 is connected.

The utility model signal processor is composed in series by signal processor 10, single-chip microcomputer 11, storer 17.The input termination A/D transducer (9) of signal processor, the output termination D/A transducer 18 of storer, serial line interface 15 and peripheral circuit are connected on the input end and the output terminal of single-chip microcomputer 11 respectively.

Peripheral circuit of the present utility model comprises the current loop circuit that display 12, function key 13, controller 14, alarm 16 and D/A transducer 20, electric current loop 21, secondary instrument 22 are composed in series.These circuit are connected on single-chip microcomputer 11 corresponding input end and output terminals respectively.

Timer circuit of the present utility model is composed in series by crystal oscillator 23, frequency divider 24.An output signal of frequency divider is delivered to A/D transducer 9 and D/A transducer 17 respectively, and another output signal is sent into the controlling of sampling end of A/D transducer 9.

The utlity model has reasonable in design, simple, detect characteristics such as tank level from motion tracking, parameters such as all right calculated reserves, show in real time, function such as warning, control, have measuring accuracy height, strong interference immunity, long-time stability good, can measure the strong advantages such as liquid of corrosivity, can be widely used in the automatic management of wet tank district.

Description of drawings:

Fig. 1 is the utility model electricity theory diagram;

Fig. 2 is the utility model signal transceiver circuit block diagram;

Fig. 3 is the utility model signal processor circuit block diagram;

Fig. 4 is the utility model peripheral circuit block diagram;

Fig. 5 is the utility model timer circuit block diagram;

Fig. 6 is the utility model electrical schematic diagram,

Fig. 7-12 the utility model electronic-circuit diagram.

Below in conjunction with accompanying drawing the technical solution of the utility model is further described:

Shown in accompanying drawing 1-12, the utility model partly is made up of in circuit etc. antenna 7 and device microwave device and the electricity in housing.The antenna 7 that is installed in wet tank 6 tops is directly launched with signal and is accepted circuit and be connected.The signal transceiver circuit is connected to form by microwave voltage controlled oscillator 1, directional coupler 2, circulator 3, attenuator 4, frequency mixer 5, balanced device 8.The output terminal of signal transceiver circuit and A/D transducer 9 and signal processor are connected in series.Signal processor is composed in series by signal processor 10, single-chip microcomputer 11, storer 17.Output terminal of signal processor is connected on the input end of signal transceiver circuit with after D/A transducer 18, smoothing filter 19 are connected.An output signal of the timer circuit that is composed in series by crystal oscillator 23, frequency divider 24 is delivered to A/D transducer 9 and D/A transducer 17 respectively, and another output signal is sent into the controlling of sampling end of A/D transducer 9.Serial line interface 15 and peripheral circuit are connected on single-chip microcomputer 11 corresponding input end and output terminals respectively.Peripheral circuit of the present utility model comprises the current loop circuit that display 12, function key 13, controller 14, alarm 16 and D/A transducer 20, electric current loop 21, secondary instrument 22 are composed in series.

The course of work of the present utility model is: by 8031 single-chip microcomputers 11 the pre-strange parameter certificate of storage in the storer 17 is delivered to D/A transducer 18, the simulating signal of D/A transducer 18 outputs is after 19 filtering of smothing filtering ripple device, excitation voltage controlled oscillator 1 makes voltage controlled oscillator 1 produce linear frequency modulation continuous wave.The main energy of this signal is sent into circulator 3 through directional coupler 2, sends through antenna 7 then; Another part energy is sent into the local oscillation signal of frequency mixer 5 as frequency mixer through attenuator 4.Antenna 7 receives a part of signal that is reflected by measured medium in the wet tank 6, send into frequency mixer 5 through circulator 3, this signal and local oscillation signal carry out mixing, output intermediate frequency (0-100KZ) signal, after equalization filter 8 filtering, give A/D transducer 9, digital signal by 9 outputs of 10 pairs of A/D transducers of digital signal processor is handled, and give 8301 single-chip microcomputers 11 with the result, 8301 single-chip microcomputers pass through display 12 as the Based Intelligent Control interface to measuring result of calculation, alarm 16, controller 14 shows in real time, liquid level warning and valve control, and, realize on-the-spot measuring ability by function key 13 input parameters.Can also will measure result of calculation by serial line interface 15 and give microcomputer network, or give secondary instrument 22, so that monitoring by the current loop circuit output current signal that is connected into of connecting with D/A transducer 20, electric current loop 21.Be composed in series system's timing circuit by crystal oscillator 23 and frequency divider 24, by frequency divider output two-way pulse timing signal, the one tunnel gives A/D transducer 9 and D/A transducer 17 as timing signal, and A/D transducer 9 is given as sampling pulse in another road.

Microwave devices such as the microwave voltage controlled oscillator 1 among the utility model figure, directional coupler 2, circulator 3, attenuator 4, frequency mixer 5, antenna 7, balanced device 8 are shaped article.A/D transducer 9 is made up of IC5 (MAX151), IC33 (74HC374), IC34 (74HC374).Signal processor 10 is made up of IC24 (TMS320C25), IC25 (2764), IC26 (2764), IC27 (IDT71256), IC28 (IDT71256), IC6 (74F08), IC7 (74F04), IC8 (74F139).Single-chip microcomputer 11 control interfaces are made up of IC1 (8031), IC29 (74HC138), IC30 (74HC139), IC31 (4060), IC32 (74HC221).Display (12) is made up of IC16 (74HC374), IC17 (74HC374), IC18 (74HC374) and 10 LED.Function key (13) is made up of IC19 (74HC04) and four buttons.Controller (14) is made up of BG1 (3DG12), diode (9004), relay.Serial line interface (15) is made up of IC9 (uA1488), IC10 (uA1489).Alarm 16 is made up of IC11 (74HC373) and alarm.Storer 17 is by IC3 (74HC373), and IC2 (27512), IC4 (6116) form.D/A transducer 18 is made up of IC20 (74HC374), IC21 (74HC374), ICD1 (AD568).The ripple device 19 that smoothly shakes is made up of ICD1 (AD840) and resistance.D/A transducer 20 is made up of ICD3 (AD7541), IC22 (74HC374), IC23 (74HC374).Electric current loop 21 is made up of ICD4 (AD694) and triode (9014).23 in crystal oscillator can be selected 4.096MHZ for use.Frequency divider 24 is selected (74HC161) for use.

Claims

1, a kind of radar level gauge, by antenna (7), microwave device and the electronic circuit etc. of device in housing partly formed, it is characterized in that electronic circuit is by the signal transceiver circuit, A/D transducer (9), signal processor, D/A transducer (18), smoothing filter (19), several parts of timer circuit and peripheral circuit are formed, antenna (7) directly is connected with the signal transceiver circuit, the output terminal of signal transceiver circuit and A/D transducer (9), signal processor is connected in series, output terminal of signal processor and D/A transducer (18), after smoothing filter (19) series connection, be connected on the input end of signal transceiver circuit, two output terminals of timer circuit are connected with the A/D transducer respectively, one of them output terminal is connected with the D/A transducer simultaneously, and peripheral circuit is connected on the output terminal and the input end of signal processor respectively.

2, radar level gauge according to claim 1, it is characterized in that the signal output part of the microwave voltage controlled oscillator (1) of signal transceiver circuit is connected the input end of directional coupler (2), an output terminal of this directional coupler is connected with circulator (3), another output terminal links to each other with attenuator (4), one end of circulator and frequency mixer (5) join, the other end links to each other with the antenna (7) that is installed in wet tank (6) top, the output terminal of attenuator (4) connects another input end of frequency mixer (5), frequency mixer (5) with connect A/D transducer (9) after balanced device (8) is connected.

3, radar level gauge according to claim 1, it is characterized in that signal processor is composed in series by signal processor (10), single-chip microcomputer (11), storer (17), the input termination A/D transducer (9) of signal processor, the output termination D/A transducer (18) of storer, serial line interface (15) and peripheral circuit are connected on the input end and the output terminal of single-chip microcomputer (11) respectively.

4, radar level gauge according to claim 1, it is characterized in that peripheral circuit comprises the current loop circuit that display (12), function key (13), controller (14), alarm (16) and D/A transducer (20), electric current loop (21), secondary instrument (22) are composed in series, these circuit are connected on corresponding input end of single-chip microcomputer (11) and output terminal respectively.

5, radar level gauge according to claim 1 is characterized in that timer circuit is composed in series by crystal oscillator (23), frequency divider (24).