CN201503341U

CN201503341U - Sulfur hexafluoride gas leak detector

Info

Publication number: CN201503341U
Application number: CN2009202235701U
Authority: CN
Inventors: 秦志阳; 庞庆胜; 李波; 刘万兵; 何亚辉; 陈尚志; 刘建功; 王新宇
Original assignee: Pingdingshan City Of Quality And Technical Supervision And Testing Center
Current assignee: Pingdingshan City Of Quality And Technical Supervision And Testing Center
Priority date: 2009-09-18
Filing date: 2009-09-18
Publication date: 2010-06-09
Anticipated expiration: 2019-09-18

Abstract

The utility model relates to an instrument for detecting gas leakage, in particular to a leak detector for detecting leakage of sulfur hexafluoride gas, which comprises a sensor, a detecting-controlling circuit, a signal display circuit, a probe, a vacuum pump and a power circuit. The sensor is composed of a radio frequency oscillator and an ionization chamber capable of low-pressure glow discharge. The radio frequency oscillator is a self-excited oscillation circuit formed by two symmetrical triodes, and an oscillation coil of the self-excited oscillation circuit is a planar oscillation coil. The ionization chamber capable of low-pressure glow discharge comprises a gas guide tube and a pair of symmetrical polar plates arranged outside the gas guide tube. The detecting-controlling circuit comprises a frequency divider and a microprocessor. The signal display circuit comprises a simulation bar display and a digital display. The Sulfur hexafluoride gas leak detector has the advantages of low detection limit, high sensibility and stability, fine repeatability, direct reading, easy operation, strong capacity for emergent accidents and capability of realizing qualitative and quantitative detection.

Description

The sulfur hexafluoride gas leak locator

Technical field

The utility model relates to the instrument that a kind of detected gas is revealed, particularly a kind of leak locator that detects the sulfur hexafluoride gas leakage.

Background technology

The sulfur hexafluoride gas leak locator is to manufacture the indispensable visual plant of sulfur hexafluoride gas switch.Detect the instrument that sulfur hexafluoride gas leaks at present, mainly by sensor, signal processor and signal display circuit are formed, described sensor comprises a metal shell, be provided with an one metal wire as anode in these housing central authorities, on the top of this housing, be provided with a tested gas inlet, on this housing, draw the negative electrode of a lead as this instrument, when being connected with high voltage on the sensor, around described tinsel, can produce the corona discharge phenomenon, in the time of in tested sulfur hexafluoride gas enters described metal shell, described this corona discharge current promptly reduces, thereby record the leakage that has or not sulfur hexafluoride gas, the major defect of above-mentioned detector is that sensitivity is low, just can measure when promptly having only the concentration of leaking when sulfur hexafluoride gas higher.

We find existing various leak locator poor stability, qualitative leak detection simultaneously and quantitative leak the two can not carry out simultaneously in to the process of sulfur hexafluoride gas leak locator calibrating, calibration was complicated before instrument used, also will look into curve tables again according to instrument readings during quantitative leak obtains a result, it is loaded down with trivial details to work, sample of signal is obtained radiofrequency signal from collector, reveals at sulfur hexafluoride gas commonly used and checks the linearity and the poor sensitivity of working in the concentration range.Be unfavorable for tackling the accident that sulfur hexafluoride gas is revealed.

The utility model content

The purpose of this utility model will provide a kind of sulfur hexafluoride gas leak locator exactly, this sulfur hexafluoride gas leak locator detects that line is low, sensitivity and stability height, good reproducibility, directly reading, easily operation and solution of emergent event ability by force, can realize qualitative and quantitative analysis.

The technical solution of the utility model is achieved in that

A kind of sulfur hexafluoride gas leak locator, it comprises sensor 1, telemetry circuit 2, signal display circuit 3, probe 12, vacuum pump 13, power circuit 14, wherein said sensor 1 is made up of the ionization chamber 5 of radio-frequency oscillator 4 and infrabar glow discharge.

The technical solution of the utility model can be achieved in that a kind of sulfur hexafluoride gas leak locator, the self-maintained circuit that the triode that described radio-frequency oscillator 4 is two symmetries is formed, and its concussion coil is a planar oscillation coil 15.

The technical solution of the utility model can also be achieved in that a kind of sulfur hexafluoride gas leak locator, and the ionization chamber 5 of described infrabar glow discharge includes wireway 6 and at the pole plate 7 of a pair of symmetry of wireway 6 outsides.

The technical solution of the utility model can also be achieved in that a kind of sulfur hexafluoride gas leak locator, and described telemetry circuit 2 comprises frequency divider 8 and microprocessor 9.

The technical solution of the utility model can also be achieved in that a kind of sulfur hexafluoride gas leak locator, and described signal display circuit 3 comprises that demonstration 10 of simulation bar and numeral show 11.

The beneficial effects of the utility model are:

1, adopted the radio-frequency oscillator of planar oscillation coil, because so the planar oscillation coil has reduced manufacturability that spatial volume improved assembly, has reduced the influence to stray capacitance, improved the corrosivity of Chinese People's Anti-Japanese Military and Political College's gas of coil, thereby improved the self stability of oscillator, improved sensitivity.

2, the utility model sample of signal is to obtain signal from emitter, has improved the stability of sensor, good reproducibility.

3, frequency divider and microprocessor processes signal have been used, so can directly show and the digital result who demonstrates detection from the simulation bar, sulfur hexafluoride gas is carried out qualitative and detection by quantitative, need not carry out complicated computing again, simple to operate, help solution of emergent event.

Description of drawings:

Fig. 1 is the utility model structural representation;

Fig. 2 is the utility model sensor construction synoptic diagram;

Fig. 3 is the electrical schematic diagram of the utility model radio-frequency oscillator.

Embodiment:

The utility model is described in further detail below in conjunction with accompanying drawing and specific embodiment.

Referring to Fig. 1, Fig. 2, Fig. 3, the sulfur hexafluoride gas leak locator comprises sensor 1, telemetry circuit 2, signal display circuit 3, probe 12, vacuum pump 13, power circuit 14, sensor 1 is made up of the ionization chamber 5 of radio-frequency oscillator 4 and infrabar glow discharge, the ionization chamber 5 of infrabar glow discharge in the present embodiment is called for short ionization chamber 5, and ionization chamber 5 is connected with probe 12 with vacuum pump 13; Radio-frequency oscillator 4 is the self-maintained circuit of being made up of the triode of two symmetries, and its concussion coil is a planar oscillation coil 15, is exactly that oscillator coil is tiled on the printed circuit board (PCB) with spiral ring, and sample of signal is obtained from the emitter 16 of triode; Ionization chamber 5 comprises wireway 6 and at the pole plate 7 of a pair of symmetry of wireway 6 outsides, and pole plate 7 reality of a pair of symmetry of wireway 6 outsides are the electric capacity in the oscillation circuit in the self-maintained circuit formed of the symmetrical triode of two of radio-frequency oscillator 4; Telemetry circuit 2 comprises frequency divider 8 and microprocessor 9; Signal display circuit 3 comprises that demonstration 10 of simulation bar and numeral show 11; Power circuit 14 is powered simultaneously for sensor 1, telemetry circuit 2, signal display circuit.

Referring to Fig. 1, Fig. 2, tested gas sucks and passes through the wireway 6 of ionization chamber 5 during leak locator work from detecting head 12 under the effect of vacuum pump 13, leave from the B mouth of vacuum pump 13, the air that the symmetry pole plate is 7 produces ionic discharge under the effect of high-frequency electric field, thereby when entering 7 on symmetrical pole plate, the gas that contains sulfur hexafluoride changes the existence that oscillatory regime that discharge condition changes radio-frequency oscillator 4 is come the perception sulfur hexafluoride gas, signal makes the simulation bar show that 10 pilot lamp is bright after telemetry circuit 2 comprises frequency divider 8 and microprocessor 9, illustrate to have sulfur hexafluoride gas, just finished qualitative detection.

Radio frequency oscillator 4 is to be operated in from ceasing duty, it discharges the air ionization in the ionization chamber 5 for ionization chamber 5 provides high-frequency energy, thereby after sulfur hexafluoride gas enters ionization chamber 5, change discharge condition and change the state of radio-frequency oscillator 4 from breath, certainly the state that ceases of telemetry circuit 2 measurement radio-frequency oscillators 4 and processing back show that by the numeral of signal display circuit 3 11 demonstrate the concentration of sulfur hexafluoride, thereby have finished detection by quantitative.

As shown in Figure 3, because the radio-frequency oscillator 4 of sulfur hexafluoride gas leak locator is a high sensitivity, the higher sensor of stability, the spike pulse that ceases certainly of seeing the emitter of triode in the radio-frequency oscillator 4 with oscillograph is to beat back and forth around the center to blur into the waveform of a slice, the direct measurement of sort signal all there is difference at every turn, can make charactron show the indefinite numeral that do not see, therefore after radio-frequency oscillator 4 obtains signal, and insert a frequency divider 8 between the follow-up metering circuit, the signal after the frequency division shaping is directly given microprocessor.

The triode that two symmetries are arranged in the radio-frequency oscillator 4, sample of signal is obtained signal from the emitter 16 of triode, adopts the electronegative potential low output resistance circuit way of output, and the frequency maximal value is 120 kilo hertzs.The traditional circuit sample of signal is to obtain radiofrequency signal by tunable capacitor from collector, rf frequency 60 megahertzes.(the not too regular spike pulse of breath certainly is transformed into rectangular wave pulse waveform shape, has improved the stability of sensor after the sample of signal frequency division of the present utility model shaping.Signal directly send after by the shaping frequency division microprocessor 9 to handle.Carry out staging treating according to actual conditions, thereby obtain desirable effect signal.Set up the internal work curve by microprocessor 9, the calibration point during with calibration is the concentration that basic calculation goes out the arbitrfary point.

The utility model is work like this: connect 220 volts of power supplys of interchange and beat power switch device, this moment, power light and vacuum pump 13 time dalay indicator lights lighted, and can hear the vacuum pump 13 normal sound that start, if instrument is the oil level that first use will be checked vacuum pump 13, pasta should be positioned at the oil ga(u)ge midline, instrument starts about 15 minutes final vacuum pump 13 delayed lamps and extinguishes, relay indicating light lights and enters duty, when leak detection (having tested gas sulfur hexafluoride), under the effect of vacuum pump 13, tested gas is sucked from detecting head 12, discharge from the B mouth of vacuum pump 13 through the wireway 6 of ionization chamber 5; When tested gas is ionized under the effect at high-frequency electric field during through ionization chamber 5, thereby influence the duty of radio-frequency oscillator 4; Change and to perceive the amount whether sulfur hexafluoride gas exist and exist what are arranged thereby telemetry circuit 2 detects the oscillation frequency of radio-frequency oscillator 4.Under the condition of no any tested gas, the simulation bar shows that the pilot lamp of 10 screens all extinguishes, and leaking concentration is zero; When having tested gas sulfur hexafluoride, pass to signal display circuit 3 after the processing through the microprocessor 9 in the telemetry circuit 2, show the quantitative leak result.Complete machine is worked under the electric power supply of power circuit 14.The utility model can also be applied on other gases.

Claims

1. sulfur hexafluoride gas leak locator, it comprises sensor (1), telemetry circuit (2), signal display circuit (3), probe (12), vacuum pump (13), power circuit (14), and it is characterized in that: described sensor (1) is made up of the ionization chamber (5) of radio-frequency oscillator (4) and infrabar glow discharge.

2. sulfur hexafluoride gas leak locator according to claim 1 is characterized in that: described radio-frequency oscillator (4) is the self-maintained circuit that the triode of two symmetries is formed, and its concussion coil is planar oscillation coil (15).

3. sulfur hexafluoride gas leak locator according to claim 1 is characterized in that: the ionization chamber of described infrabar glow discharge (5) includes the pole plate (7) of wireway (6) and a pair of symmetry outside wireway (6).

4. sulfur hexafluoride gas leak locator according to claim 1 is characterized in that: described telemetry circuit (2) comprises frequency divider (8) and microprocessor (9).

5. sulfur hexafluoride gas leak locator according to claim 1 is characterized in that: described signal display circuit (3) comprises that the simulation bar shows that (10) and numeral show (11).