CN201488743U - Broken line protection circuit of frequency sensor - Google Patents
Broken line protection circuit of frequency sensor Download PDFInfo
- Publication number
- CN201488743U CN201488743U CN2009202077873U CN200920207787U CN201488743U CN 201488743 U CN201488743 U CN 201488743U CN 2009202077873 U CN2009202077873 U CN 2009202077873U CN 200920207787 U CN200920207787 U CN 200920207787U CN 201488743 U CN201488743 U CN 201488743U
- Authority
- CN
- China
- Prior art keywords
- circuit
- resistance
- discharge circuit
- filtering
- frequency
- 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 - Lifetime
Links
Images
Landscapes
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
The utility model discloses a broken line protection circuit of a frequency sensor, wherein the input end thereof inputs two frequency signals of the frequency sensor, the broken line protection circuit comprises a filtering and charging-discharging circuit and an operational circuit which are connected in series, and the filtering and charging-discharging circuit achieves the filtering or the charging-discharging of input signals, and outputs signals to the operational circuit. The operational circuit receives output signals of the filtering and charge-discharge circuit, thereby achieving the shaping of the frequency signals or to be used as a square wave generator to generate square waves. The broken line protection circuit of the frequency sensor has definite broken line alarm frequency, combines an original shaping circuit and a broken line circuit together, and simplifies the structure of the circuit.
Description
Technical field
The utility model relates to the monitoring field in the engine, relates in particular to a kind of disconnection protection circuit for frequency sensor.
Background technology
See also Fig. 1,, comprise shaping circuit 1 ' and broken string circuit 2 ' for present typical frequencies broken string shaping circuit.
Shaping circuit 1 ' is shaped as the standard square wave of same frequency, the carry-out bit standard square wave that promptly A ' locates among the figure by switch triode Q1 and the first Schmidt trigger U1A with input frequency signal F+, F-.
Broken string circuit 2 ' implementation method is as follows: when speed probe just often, be that input frequency signal F+, F-are when importing normal signal, the standard square wave that A ' locates is after resistance R 6 ', capacitor C 2 ' filtering, locate to export the threshold value of " 0 " that is lower than the second Schmidt trigger U1B at B ', changing threshold value is 0.3V, makes the C place be " 1 " high level; When speed probe F+ " broken string ", B ' locates level and is directly drawn high by Vcc and be " 1 ", makes the C place be " 0 ", realizes break alarm.
Because the threshold value of the second Schmidt trigger U1B " 0 " is 0.3V, threshold value is very low, wants to realize that being lower than 50Hz frequency sensor operate as normal does not carry out break alarm, must add capacitor C 2 ' enough big.
Summary of the invention
The purpose of this utility model is to overcome the defective of prior art and a kind of disconnection protection circuit for frequency sensor is provided, and it has clear and definite break alarm frequency, and simple in structure.
The technical scheme that realizes above-mentioned purpose is: a kind of disconnection protection circuit for frequency sensor, and two frequency signals of its input end incoming frequency sensor, wherein, it comprises filtering and charge-discharge circuit and the discharge circuit that is connected in series, wherein:
Described filtering and charge-discharge circuit are realized the filtering of input signal or are discharged and recharged, output signal to described discharge circuit;
Described discharge circuit is accepted the output signal from filtering and charge-discharge circuit, realizes the shaping of frequency signal or carries out the generation of square wave as square-wave generator.
Above-mentioned disconnection protection circuit for frequency sensor, wherein,
Described filtering and charge-discharge circuit comprise second resistance R 2 and second capacitor C 2 of series connection, also comprise first resistance R 1, first capacitor C 1, the first diode D1 and the second diode D2, wherein:
One end ground connection of described first resistance R 1 and accept the frequency signal of an input, the other end links to each other with an end of second resistance R 2 and accepts the frequency signal of another input;
One end ground connection of described first capacitor C 1, the other end are connected between described second resistance R 2 and second capacitor C 2;
The plus earth of the described first diode D1, negative pole links to each other with an end that exports discharge circuit to of described second capacitor C 2;
The negative pole of the described second diode D2 connects power Vcc, and the negative pole of the anodal and described first diode D1 links to each other;
Described discharge circuit comprises an operational amplifier, the signal that its negative input end is accepted from filtering and charge-discharge circuit by one the 3rd resistance R 3, also be connected to the output terminal of this operational amplifier by one the 4th resistance R 4, the positive input terminal of described operational amplifier is connected to the output terminal of this operational amplifier by one the 4th capacitor C 4.
Above-mentioned disconnection protection circuit for frequency sensor, wherein, the positive input terminal of described operational amplifier also links to each other with power Vcc by one the 5th resistance R 5 respectively, by one the 6th resistance R, 6 ground connection.
The beneficial effects of the utility model are: disconnection protection circuit for frequency sensor of the present utility model has clear and definite break alarm frequency, and it with original shaping circuit and the broken string circuit combine, simplified circuit structure.
Description of drawings
Fig. 1 is the circuit diagram of the frequency broken string shaping circuit of prior art;
Fig. 2 is the circuit diagram of disconnection protection circuit for frequency sensor of the present utility model.
Embodiment
The utility model is described in further detail below in conjunction with accompanying drawing.
See also Fig. 2; there is shown a kind of disconnection protection circuit for frequency sensor of the present utility model; two frequency signal F+ of its input end incoming frequency sensor and F-, the utility model comprises filtering and charge-discharge circuit 1 and the discharge circuit 2 that is connected in series, wherein:
Filtering and charge-discharge circuit 1 are realized the filtering of input signal or are discharged and recharged, output signal to discharge circuit 2, this filtering and charge-discharge circuit 1 comprise second resistance R 2 and second capacitor C 2 of series connection, also comprise first resistance R 1, first capacitor C 1, the first diode D1 and the second diode D2, wherein:
One end ground connection of first resistance R 1 and accept one the input frequency signal F-, the other end with
One end of second resistance R 2 links to each other and accepts the frequency signal F+ of another input;
One end ground connection of first capacitor C 1, the other end are connected between second resistance R 2 and second capacitor C 2;
The plus earth of the first diode D1, negative pole links to each other with an end that exports discharge circuit 2 to of second capacitor C 2;
The negative pole of the second diode D2 connects power Vcc, and positive pole links to each other with the negative pole of the first diode D1;
The output signal that discharge circuit 2 is accepted from filtering and charge-discharge circuit 1, realization is to the shaping of frequency signal or carry out the generation of square wave as square-wave generator, it comprises an operational amplifier U1, the signal that its negative input end is accepted from filtering and charge-discharge circuit 1 by one the 3rd resistance R 3, also be connected to the output terminal of this operational amplifier U1 by one the 4th resistance R 4, the positive input terminal of operational amplifier U1 is connected to the output terminal of this operational amplifier U1 by one the 4th capacitor C 4.
The positive input terminal of operational amplifier 2 also links to each other with power Vcc by one the 5th resistance R 5 respectively, by one the 6th resistance R, 6 ground connection.
In the present embodiment, it is LM258 that operational amplifier U1 adopts model.
Principle of work of the present utility model is as follows:
As the frequency signal F+ of frequency sensor, when F-imports normal frequency signal, filtering and the charge-discharge circuit 1 main filter function of realizing, second resistance R 2 and first capacitor C 1 are formed low-pass filter, the filtering high fdrequency component, the second resistance C2 filtering DC component, discharge circuit is realized the shaping to frequency signal as voltage comparator 2 this moments.
Behind frequency signal F+ broken string, filtering and charge-discharge circuit 1 main realization discharge and recharge function, discharge circuit 2 becomes a square-wave generator at this moment, first capacitor C 1, second capacitor C 2, the 3rd resistance R 3 and the 4th resistance R 4 form charging and discharging circuit, make output terminal B place level overturn automatically, the output high frequency square wave, frequency is by first capacitor C 1, second capacitor C 2, the 3rd resistance R 3,4 decisions of the 4th resistance R, general value is 1.5 times of maximum input speed, by detecing other B place frequency is when breaking frequency, can be judged to be broken string.
Below embodiment has been described in detail the utility model in conjunction with the accompanying drawings, and those skilled in the art can make the many variations example to the utility model according to the above description.Thereby some details among the embodiment should not constitute qualification of the present utility model, and the scope that the utility model will define with appended claims is as protection domain of the present utility model.
Claims (3)
1. disconnection protection circuit for frequency sensor, two frequency signals of its input end incoming frequency sensor is characterized in that, it comprises filtering and charge-discharge circuit and the discharge circuit that is connected in series, wherein:
Described filtering and charge-discharge circuit are realized the filtering of input signal or are discharged and recharged, output signal to described discharge circuit;
Described discharge circuit is accepted the output signal from filtering and charge-discharge circuit, realizes the shaping of frequency signal or carries out the generation of square wave as square-wave generator.
2. disconnection protection circuit for frequency sensor according to claim 1 is characterized in that,
Described filtering and charge-discharge circuit comprise second resistance R 2 and second capacitor C 2 of series connection, also comprise first resistance R 1, first capacitor C 1, the first diode D1 and the second diode D2, wherein:
One end ground connection of described first resistance R 1 and accept the frequency signal of an input, the other end links to each other with an end of second resistance R 2 and accepts the frequency signal of another input;
One end ground connection of described first capacitor C 1, the other end are connected between described second resistance R 2 and second capacitor C 2;
The plus earth of the described first diode D1, negative pole links to each other with an end that exports discharge circuit to of described second capacitor C 2;
The negative pole of the described second diode D2 connects power Vcc, and the negative pole of the anodal and described first diode D1 links to each other;
Described discharge circuit comprises an operational amplifier, the signal that its negative input end is accepted from filtering and charge-discharge circuit by one the 3rd resistance R 3, also be connected to the output terminal of this operational amplifier by one the 4th resistance R 4, the positive input terminal of described operational amplifier is connected to the output terminal of this operational amplifier by one the 4th capacitor C 4.
3. disconnection protection circuit for frequency sensor according to claim 2 is characterized in that, the positive input terminal of described operational amplifier also links to each other with power Vcc by one the 5th resistance R 5 respectively, by one the 6th resistance R, 6 ground connection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009202077873U CN201488743U (en) | 2009-08-13 | 2009-08-13 | Broken line protection circuit of frequency sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009202077873U CN201488743U (en) | 2009-08-13 | 2009-08-13 | Broken line protection circuit of frequency sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201488743U true CN201488743U (en) | 2010-05-26 |
Family
ID=42427617
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2009202077873U Expired - Lifetime CN201488743U (en) | 2009-08-13 | 2009-08-13 | Broken line protection circuit of frequency sensor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN201488743U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101629977B (en) * | 2009-08-13 | 2011-09-07 | 中国船舶重工集团公司第七一一研究所 | Disconnection protection circuit for frequency sensor |
| CN104483503A (en) * | 2014-11-19 | 2015-04-01 | 成都嵌智捷科技有限公司 | Conditioning circuit capable of outputting stable vehicle speed pulse signal |
| CN115790966A (en) * | 2022-11-17 | 2023-03-14 | 中国航发西安动力控制科技有限公司 | Piezoresistive pressure sensor disconnection alarming and signal collecting circuit |
-
2009
- 2009-08-13 CN CN2009202077873U patent/CN201488743U/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101629977B (en) * | 2009-08-13 | 2011-09-07 | 中国船舶重工集团公司第七一一研究所 | Disconnection protection circuit for frequency sensor |
| CN104483503A (en) * | 2014-11-19 | 2015-04-01 | 成都嵌智捷科技有限公司 | Conditioning circuit capable of outputting stable vehicle speed pulse signal |
| CN115790966A (en) * | 2022-11-17 | 2023-03-14 | 中国航发西安动力控制科技有限公司 | Piezoresistive pressure sensor disconnection alarming and signal collecting circuit |
| CN115790966B (en) * | 2022-11-17 | 2024-07-23 | 中国航发西安动力控制科技有限公司 | Piezoresistive pressure sensor disconnection alarm and signal acquisition circuit |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101174770B (en) | Charging protection device | |
| CN103107518B (en) | A kind of photovoltaic DC-to-AC converter and protective device thereof | |
| CN101629977B (en) | Disconnection protection circuit for frequency sensor | |
| CN202931282U (en) | General telecommand acquisition module for distribution network terminal | |
| CN101320058A (en) | Intelligent light emission/receiving control device of thunder and lightning test equipment of overvoltage protector | |
| CN202042870U (en) | Improved monitoring and alarming device for communication power supply system | |
| CN201488743U (en) | Broken line protection circuit of frequency sensor | |
| CN105067945A (en) | Intelligent detection unit with direct-current arcing detection function and junction box | |
| CN106842013A (en) | The live detection method and device of the contact of breaker ablation degree based on electromagnetic wave | |
| CN204287307U (en) | Transformer, current detection circuit based on transformer | |
| CN205248853U (en) | Power supply circuit | |
| CN105429115A (en) | Photovoltaic power generation system, photovoltaic direct current cable protection device and control method thereof | |
| CN206559098U (en) | A kind of lithium battery USB quick charges manage circuit | |
| CN203218871U (en) | Low-power nickel-hydrogen battery protection circuit | |
| CN106787103A (en) | A kind of photovoltaic charged control system of automatic detection intensity of illumination | |
| CN208028620U (en) | A kind of lithium battery is full of automatically cutting off protection circuit | |
| CN203859538U (en) | Charging protection circuit and bluetooth loudspeaker box | |
| CN206379761U (en) | The electric toothbrush wireless charging device that a kind of utilization USB charger is powered | |
| CN210111651U (en) | Battery self-discharge prevention circuit and charger | |
| CN204836131U (en) | Effective switch input signal acquisition circuit of high level | |
| CN210015153U (en) | Active electromagnetic interference electricity stealing alarm device | |
| CN205317888U (en) | Join in marriage electric network line trouble recognition device | |
| CN203479947U (en) | Multi-series lithium battery disconnection detection circuit | |
| CN103048591A (en) | Power grid environment monitoring circuit | |
| CN210323324U (en) | Ground wire connection detector of photovoltaic inverter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20100526 Effective date of abandoning: 20090813 |