CN2578825Y - Detecting alarm devices - Google Patents
Detecting alarm devices Download PDFInfo
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- CN2578825Y CN2578825Y CN 02249809 CN02249809U CN2578825Y CN 2578825 Y CN2578825 Y CN 2578825Y CN 02249809 CN02249809 CN 02249809 CN 02249809 U CN02249809 U CN 02249809U CN 2578825 Y CN2578825 Y CN 2578825Y
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- CN
- China
- Prior art keywords
- circuit
- unit
- detecting
- resistance
- detecting unit
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Abstract
The utility model relates to a detecting alarm device which is mainly used for detecting whether conducting liquid exists or not. The detecting alarm device comprises a sampling unit, a detection unit, an output unit and an execution unit for a circuit, wherein a transformer is arranged between the sampling unit and the detecting unit, and the sampling unit and the detecting unit are respectively connected with the primary side and the secondary side of the transformer; an AC wave generating circuit arranged at the secondary side provides drive current to make the primary side generate the inductive AC voltage which is applied to an exploring electrode; the detecting unit comprises a switching circuit, a rectifying and filtering circuit and a comparison circuit, wherein the switching circuit converts a drive current signal into the voltage. Finally, the detecting unit sends out an execution signal to the execution circuit which comprises a light emitting diode, a transistor and a relay. The utility model has the advantages of simple structure, small size and low error action rate. Because an exploring circuit and an explored circuit are electrically isolated, the utility model perfectly protects an exploring device, avoids the interference, effectively improves the service life of the exploring electrode, effectively avoids the damage caused by the high-voltage coupling or the lightning of the detected environment, and can monitor the detected environment in real time.
Description
Technical field
The utility model relates to a kind of sniffer of alarm monitor, is meant a kind of detecting alarm and circuit of whether existing at need acquisition environment water or other conducting liquids of being used for especially.
Background technology
Existing various alarm monitor lays particular emphasis on anti-theft feature more, then often need in other respects as survey water or whether other conducting liquids exist or not water logging, leakage etc. at industrial control field, but the research and development of this respect is then done lessly, even does not relate to substantially.As the disclosed a kind of alert detecting device of Chinese ZL92239350.8 patent " the polycore cable bundle is to line, short circuit, thread break detector ", form by the major-minor machine, the major-minor machine connects tested cable two ends respectively during measurement; Owing to must adopt the two ends monitoring, nature can produce cost height, slow, the inefficient disadvantage of feedback, and is in many cases remote or even infeasible because of distance, and whether water or other conducting liquids soaked protected object specialize in; Also there is same problem in China's ZL92226127.X patent " multi-core cable tester " for the design content that shows.In addition, also there is following shortcoming in prior art: one, do not have electrical isolation between testing circuit and fluid to be measured; Its two, poor anti jamming capability, malfunction rate height when under rugged surroundings, working; Its three, survey and mostly to be direct current with current signal, easily make exploring electrode oxidation, corrosion, shortened electrode life.
Summary of the invention
The purpose of this utility model provides a kind of volume small and exquisite, simple in structure and realization detecting unit and the single-ended detection water of external circuit electrical isolation or the detecting alarm whether other conducting liquids exist.
Designed a kind of detecting alarm according to the foregoing invention purpose, its circuit part comprises sampling unit that exploring electrode and tie constitute, accept from the sampling unit signal detecting unit, carry out the alerting signal output unit of testing result, between its circuit sampling unit and detecting unit, be provided with the isolating transformer T of buffer action
1Wherein, the circuit sampling unit is connected with the isolating transformer primary side, and detecting unit is connected with the isolating transformer secondary side, provides exciting current by the interchange wave generation circuit that is connected with the isolating transformer secondary side to it.
Described interchange wave generation circuit comprises and passes through resistance R mutually
2The operational amplifier U that connects
1A, U
1B, and peripheral resistance R
3And capacitor C
3, C
4, C
5Interchange ripple through exchanging the wave generation circuit generation is through operational amplifier U
1C, triode Q
1, Q
2Input to isolating transformer T after the power amplification
1And detecting unit comprises the change-over circuit that the exciting current conversion of signals is become voltage, change-over circuit is connected with the second-order active filter circuit with half-wave rectification, half-wave rectification is connected with comparator circuit with the second-order active filter circuit, and comparator circuit sends the execution signal to executive circuit.Change-over circuit comprises the resistance R that exciting current is converted to voltage signal
1, operational amplifier U
1DAnd resistance R
7, R
6, R
9Half-wave rectification and second-order active filter circuit comprise by operational amplifier U
2A, diode D
1The half-wave rectifying circuit of forming and by operational amplifier U
2B, resistance R
10, R
11, capacitor C
6, C
7Two power filters of forming; Comparator circuit comprises hysteresis comparator U
2C, resistance R
14, R
15And regulator potentiometer RP
1In addition, comprise LED, triode Q in addition
2, relay J DQ
1Executive circuit.
The utility model compared with prior art, volume simple in structure is little, cost amplification is low, the misoperation rate is low.Owing to utilized dexterously in the big or small key property that is inversely proportional to secondary side current of the load of transformer primary side; and superseded DC circuit connecting mode is used electromagnetic induction principle instead and is surveyed; both solved the electrical isolation problem between detection circuit and tested conducting liquid; the antijamming capability and the reliability of detection circuit have been improved again; and perfect the sniffer of having protected; evaded unnecessary interference; effectively avoided the damage that causes because of test environment coupled high voltage or thunder and lightning; and can monitor in real time test environment, improve and ensured managerial personnel's work efficiency.
Description of drawings
Accompanying drawing 1 is a theory diagram of the present utility model; Accompanying drawing 2 is electrical principle synoptic diagram of the present utility model; Accompanying drawing 3 is to exchange wave producer circuit theory synoptic diagram in the accompanying drawing 1; Accompanying drawing 4 is testing circuit principle schematic in the accompanying drawing 1.
Specific embodiments
With reference to each accompanying drawing.Mentality of designing of the present utility model is, the signal of test environment through survey conducting liquid, two metal detection electrode J that separate
1, J
2, with isolating transformer T
1Primary side connect; Secondary side at isolating transformer, the exciting current of alternation is provided to transformer by an interchange wave producer, and the size of the pull-up resistor of this exciting current and the isolating transformer primary side relation of being inversely proportional to, promptly the pull-up resistor of isolating transformer primary side is big more, and exciting current is more little; When with this exciting current after testing circuit conversion be that voltage signal and a bias voltage (being test environment voltage just often) are when comparing, just can judge whether test environment the immersion or the leakage phenomenon of conducting liquid such as water etc. occur, whether test environment be had the purpose that conducting liquid leaks or existence is monitored thereby reach.
When installing, at first exploring electrode is installed in the environment that to monitor the tie of exploring electrode and isolating transformer T of the present utility model on the spot
1Primary side connect.At isolating transformer T
1Secondary side, the effect that exchanges wave generation circuit is that to provide exciting current to the transformer that plays buffer action also be drive current, its running parameter is T by formula
0=2 π √ C
4C
5R
3R
4, making at alternating voltage that is lower than 36 volts of primary side generation and put on exploring electrode, the impedance when between exploring electrode changes and will cause the secondary side drive current variations.In testing circuit, the exciting current process is by amplifier U
2AAnd resistance R
7, R
1, R
6, R
9The I/U change-over circuit of forming is converted to voltage signal, changes a DC voltage that is directly proportional with exciting current into through half-wave rectification and second-order active filter again, and this DC voltage is imported by amplifier U
2BThe hysteresis comparator and the bias voltage U that form
0Relatively, can detect test environment whether by water logging or the situation that has other conducting liquids to exist.
When using at the scene, the liquid exploring electrode is inserted isolating transformer T
1Primary side.At T
1Secondary side, by amplifier U
1A, U
1BAnd resistance R
2-4, capacitor C
3～5The interchange ripple that the interchange wave circuit of forming produces is through amplifier U
1CWith triode Q
1, Q
3Give T after the power amplification
1Exciting current is provided.The size of the pull-up resistor of this exciting current and the isolating transformer primary side relation of being inversely proportional to is so the size of exciting current has reflected tested interelectrode resistance sizes.This exciting current is through resistance R
1Be converted to voltage signal again through amplifier U
1DHomophase amplifies, and the voltage signal of amplification passes through U
2AAnd diode D
1The half-wave rectifying circuit and the amplifier U that form
2B, resistance R
10, R
11, capacitor C
6, C
7The second-order active filter circuit of forming changes a direct current voltage U into
iImpedance is greater than 50K Ω, then with T when supposing between tested electrode no conducting liquid
1Primary side pull-up resistor U when being 50K Ω
iMagnitude of voltage U
0As hysteresis comparator U
2CCritical voltage, regulator potentiometer RP
1, make the negative input end voltage of comparer equal U
0(pull-up resistor is 50K Ω).At this moment, when pull-up resistor during greater than 50K Ω (being not have conducting liquid between exploring electrode), exciting current reduces, U
iLess than U
0, comparer U
2COutput low level, triode Q
2End relay J DQ
1Be failure to actuate LED
1Bright, expression normally is not have conducting liquid between exploring electrode; Otherwise when pull-up resistor during less than 50K Ω (being that conducting liquid is arranged between exploring electrode), exciting current increases, U
iGreater than U
0, comparer U
2CBe output as high level, triode Q
2Conducting, relay J DQ
1Action, LED
2Bright, the expression alarm is that conducting liquid is arranged between exploring electrode.Also can install the alarm device of other types such as hummer etc. in the practicality as required additional.
In addition, the utility model also can be used for liquid level detection device, and the testing circuit of resistance type sensor.Have the electric elements of circuit buffer action such as inductance etc. equally, as required instead of transformers.
Claims (6)
1, a kind of detecting alarm, its circuit part comprises sampling unit that exploring electrode and tie constitute, accept from the sampling unit signal detecting unit, carry out the alerting signal output unit of testing result, it is characterized in that between circuit sampling unit and detecting unit, being provided with the isolating transformer T of buffer action
1
2, alarm detector according to claim 1, it is characterized in that the circuit sampling unit is connected with the isolating transformer primary side, provide the detecting unit of exciting current to be connected to it with the isolating transformer secondary side by the interchange wave generation circuit that is connected with the isolating transformer secondary side.
3, alarm detector according to claim 2, it is characterized in that described interchange wave generation circuit comprises passes through resistance R mutually
2The operational amplifier U that connects
1A, U
1B, and peripheral resistance R
3And capacitor C
3, C
4, C
5Interchange ripple through exchanging the wave generation circuit generation is through operational amplifier U
1C, triode Q
1, Q
2Input to isolating transformer T after the power amplification
1
4, alarm detector according to claim 1 and 2, it is characterized in that described detecting unit comprises the change-over circuit that the exciting current conversion of signals is become voltage, change-over circuit is connected with the second-order active filter circuit with half-wave rectification, and half-wave rectification is connected with the comparator circuit that sends the execution signal to executive circuit with the second-order active filter circuit.
5, alarm detector according to claim 4 is characterized in that change-over circuit comprises the resistance R that exciting current is converted to voltage signal
1, operational amplifier U
1DAnd resistance R
7, R
6, R
9Half-wave rectification and second-order active filter circuit comprise by operational amplifier U
2A, diode D
1The half-wave rectifying circuit of forming and by operational amplifier U
2B, resistance R
10, R
11, capacitor C
6, C
7Two power filters of forming; Comparator circuit comprises hysteresis comparator U
2C, resistance R
14, R
15And regulator potentiometer RP
1
6, alarm detector according to claim 4 is characterized in that executive circuit comprises LED, triode Q
2, relay J DQ
1
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02249809 CN2578825Y (en) | 2002-11-21 | 2002-11-21 | Detecting alarm devices |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02249809 CN2578825Y (en) | 2002-11-21 | 2002-11-21 | Detecting alarm devices |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2578825Y true CN2578825Y (en) | 2003-10-08 |
Family
ID=33720164
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 02249809 Expired - Lifetime CN2578825Y (en) | 2002-11-21 | 2002-11-21 | Detecting alarm devices |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2578825Y (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103457572A (en) * | 2013-09-10 | 2013-12-18 | 昆山新金福精密电子有限公司 | Second-order active power filter circuit |
-
2002
- 2002-11-21 CN CN 02249809 patent/CN2578825Y/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103457572A (en) * | 2013-09-10 | 2013-12-18 | 昆山新金福精密电子有限公司 | Second-order active power filter circuit |
| CN103457572B (en) * | 2013-09-10 | 2016-06-08 | 昆山新金福精密电子有限公司 | A kind of second-order active power filter circuit |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Effective date of abandoning: 20050615 |
|
| C25 | Abandonment of patent right or utility model to avoid double patenting |