WO2001035362A1 - Photoelectric barrier - Google Patents

Photoelectric barrier Download PDF

Info

Publication number
WO2001035362A1
WO2001035362A1 PCT/EP2000/005748 EP0005748W WO0135362A1 WO 2001035362 A1 WO2001035362 A1 WO 2001035362A1 EP 0005748 W EP0005748 W EP 0005748W WO 0135362 A1 WO0135362 A1 WO 0135362A1
Authority
WO
WIPO (PCT)
Prior art keywords
signal
light barrier
receiver
transmitter
actual
Prior art date
Application number
PCT/EP2000/005748
Other languages
German (de)
French (fr)
Inventor
Joachim Tiedecke
Egbert Ronald Ivo Casimir Visscher
Original Assignee
Idm Gmbh Infrarot Sensoren
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Idm Gmbh Infrarot Sensoren filed Critical Idm Gmbh Infrarot Sensoren
Priority to AU54061/00A priority Critical patent/AU5406100A/en
Publication of WO2001035362A1 publication Critical patent/WO2001035362A1/en

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/94—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated
    • H03K17/941—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the way in which the control signals are generated using an optical detector
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
    • G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
    • G01S17/04—Systems determining the presence of a target
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • G01V8/00—Prospecting or detecting by optical means
    • G01V8/10—Detecting, e.g. by using light barriers
    • G01V8/12—Detecting, e.g. by using light barriers using one transmitter and one receiver
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00—Burglar, theft or intruder alarms
    • G08B13/18—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength
    • G08B13/181—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using active radiation detection systems
    • G08B13/183—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using active radiation detection systems by interruption of a radiation beam or barrier
    • G08B13/184—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using active radiation detection systems by interruption of a radiation beam or barrier using radiation reflectors
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B17/00—Fire alarms; Alarms responsive to explosion
    • G08B17/10—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means
    • G08B17/103—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means using a light emitting and receiving device
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B19/00—Alarms responsive to two or more different undesired or abnormal conditions, e.g. burglary and fire, abnormal temperature and abnormal rate of flow
    • G08B19/005—Alarms responsive to two or more different undesired or abnormal conditions, e.g. burglary and fire, abnormal temperature and abnormal rate of flow combined burglary and fire alarm systems
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B29/00—Checking or monitoring of signalling or alarm systems; Prevention or correction of operating errors, e.g. preventing unauthorised operation
    • G08B29/02—Monitoring continuously signalling or alarm systems
    • G08B29/04—Monitoring of the detection circuits
    • G08B29/046—Monitoring of the detection circuits prevention of tampering with detection circuits
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B29/00—Checking or monitoring of signalling or alarm systems; Prevention or correction of operating errors, e.g. preventing unauthorised operation
    • G08B29/18—Prevention or correction of operating errors
    • G08B29/20—Calibration, including self-calibrating arrangements
    • G08B29/24—Self-calibration, e.g. compensating for environmental drift or ageing of components
    • G08B29/26—Self-calibration, e.g. compensating for environmental drift or ageing of components by updating and storing reference thresholds
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K2217/00—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00
    • H03K2217/94—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00 characterised by the way in which the control signal is generated
    • H03K2217/941—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00 characterised by the way in which the control signal is generated using an optical detector
    • H03K2217/94102—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00 characterised by the way in which the control signal is generated using an optical detector characterised by the type of activation
    • H03K2217/94104—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00 characterised by the way in which the control signal is generated using an optical detector characterised by the type of activation using a light barrier

Definitions

  • the present invention relates to a light barrier with the features of the preamble of claim 1.
  • Such light barriers are known from practice, the signals of which, contrary to the general designation, do not necessarily have to consist of light, but rather can comprise general electromagnetic waves.
  • a transmitter for a beam of electromagnetic waves in particular radar, infrared or visible light, is usually provided, which emits the beam along the measurement section.
  • a receiver is provided that receives and evaluates the light beam. Transmitter and receiver can be at opposite ends of a straight line.
  • the beam can also be deflected depending on the application or via a retroreflector be reflected so that the transmitter and receiver can be arranged in a common housing.
  • the known light barriers emit a continuous beam, which generates a constant received signal in the receiver. As soon as the light barrier is interrupted, which is indicated by the absence of the beam at the receiver, a signal is triggered.
  • the signals can serve various purposes. For example, an area can be monitored for people entering it.
  • the triggering of the signal can be prevented by deflecting the beam via mirrors or reflectors to the receiver in such a way that a corridor is created which allows access without interrupting the light barrier beam.
  • This task is solved by modulating the transmission signal.
  • at least one further property of the reception signal can also be measured, for example the attenuation or the phase position. A change in one of these parameters can then be evaluated even in the case of an otherwise uninterrupted light beam in order to decide whether a signal should be triggered or not.
  • the transmission signal when it is pulsed.
  • the signal pulses can be analyzed on the basis of the transit time and the slope or the amplitude.
  • the transmitter and the receiver are arranged on the same side of the measuring section and a reflector is provided on the opposite side.
  • the reception signal is analyzed on the receiver side as an actual signal according to amplitude and transit time or according to the signal shape and if the actual signal deviates from at least one stored setpoint, a signal is triggered , If the setpoint is changed during operation with a long time constant based on the actual signal compared to an expected disturbance, changes or fluctuations in the area of the light barrier can be taken into account.
  • the target signal can be adjusted if the effectiveness of the transmitter or receiver declines as a result of aging processes or if the optics gradually become dirty.
  • the transmission signal can be emitted with a wavelength in the radar range, in the infrared range or in the visible range.
  • the object is also achieved by a method for operating a light barrier with the features of claim 7.
  • changes in the light beam such as e.g. B. Shortening the measuring path, lengthening the measuring path or a redirection to one evaluable signal. A slow adjustment of the setpoint to unavoidable changes is possible if the setpoint is continuously updated as a moving average of a large number of previously measured actual values.
  • Figure 1 A light barrier in a principle representation
  • Figure 2 a measurement signal compared to
  • Reduced amplitude reference signal such as
  • Figure 3 a measurement signal compared to
  • the transmitting and receiving unit 1 comprises a transmitter 3 with beam generating means, not shown, for example a laser diode and a corresponding beam-shaping optics. Furthermore, a receiver 4 is provided in the transmitting and receiving unit 1, which is also not closer to one contains the detector shown for transmission signals, for example in the form of an optic and a photodiode. Finally, the transmitting and receiving unit 1 also contains an electronic controller 5, which is set up to control the transmitting unit 3 and the receiving unit 4 and for external signal output.
  • the transmission unit 3 generates a light beam 6, which is directed onto the opposite retroreflector 2. In practice this reflects the light beam 6 m approximately parallel along the line 6 ⁇ back to the receiving unit 4, where the light beam is received and evaluated.
  • the transmitting and receiving unit 1 and the reflector 2 define between them a 6 and 6 ⁇ represent the monitored area, while the light beams to the measurement path.
  • FIG. 2 shows two signals recorded with the receiving unit 3, in which the X-axis represents the time and the Y-axis the measured intensity.
  • FIG. 2 shows a signal 10 with a larger amplitude and a signal 11 with a lower amplitude.
  • the runtime of the two signals is identical.
  • the signal 10 represents the undisturbed signal or the desired value of a pulsed transmission signal emitted by the transmission unit 3, reflected on the reflector 2 and registered in the reception unit 4.
  • the signal 11, in contrast, is attenuated, which with unchanged length of the measurement path 6, 6 ⁇ for an intervention m speaks the transmission properties along the signal path. For example, this signal can be generated by smoke.
  • FIG. 3 shows a representation corresponding to FIG. 2 corresponding to FIG. 2 a representation corresponding to FIG. 2 corresponding to FIG. 2 , in which a desired signal 12 and an actual signal 13 are shown.
  • the actual signal 13 has a shorter transit time between the transmitting unit 3 and the receiving unit 4 compared to the signal 12.
  • the transmission and reception unit 1 sends out a pulsed transmission signal with a specific pulse duration and pulse amplitude via the controller 5 and the transmission unit 3. With undisturbed measuring path 6, 6 ⁇ , this signal is reflected at the reflector 2 and recorded in the receiver 4. This signal is stored in the controller 5 as the desired signal and corresponds to the signals 10 and 12 in FIGS. 2 and 3.
  • the transmission of the pulsed signal is repeated regularly in the following operation, the signal received in the controller 5 being compared with the desired signal.
  • Slow changes due to aging of the electronics, temperature fluctuations or soiling of the optics or the reflector 2 are adapted by adapting the target signal with a long time constant or by forming moving averages without leading to an alarm being triggered.

Abstract

The invention relates to a photoelectric barrier which comprises a transmitter and a receiver and a measuring path interposed between said transmitter and said receiver. The transmitter transmits a sender signal along the measuring path to the receiver. The photoelectric barrier is further provided with an electronic circuit that monitors the sender signal, said sender signal being modulated.

Description

LichtschrankePhotoelectric barrier
Die vorliegende Erfindung betrifft eine Lichtschranke mit den Merkmalen des Oberbegriffs des Anspruchs 1.The present invention relates to a light barrier with the features of the preamble of claim 1.
Derartige Lichtschranken sind aus der Praxis bekannt, deren Signale entgegen der allgemeinen Bezeichnung nicht notwendigerweise aus Licht bestehen müssen, sondern allgemeine elektromagnetische Wellen umfassen können. Zur Überwachung einer Messstrecke ist üblicherweise ein Sender für einen Strahl elektromagnetischer Wellen, also insbesondere Radar, Infrarot oder sichtbares Licht, vorgesehen, der den Strahl entlang der Messstrecke aussendet. Am Ende der Messstrecke ist ein Empfanger vorgesehen, der den Lichtstrahl aufnimmt und auswertet. Sender und Empfanger können an gegenüberliegenden Enden einer geraden Linie liegen. Der Strahl kann auch e nach Anwendung umgelenkt oder über einen Retroreflektor reflektiert werden, so dass Sender und Empfanger in einem gemeinsamen Gehäuse angeordnet werden können.Such light barriers are known from practice, the signals of which, contrary to the general designation, do not necessarily have to consist of light, but rather can comprise general electromagnetic waves. To monitor a measurement section, a transmitter for a beam of electromagnetic waves, in particular radar, infrared or visible light, is usually provided, which emits the beam along the measurement section. At the end of the measuring section, a receiver is provided that receives and evaluates the light beam. Transmitter and receiver can be at opposite ends of a straight line. The beam can also be deflected depending on the application or via a retroreflector be reflected so that the transmitter and receiver can be arranged in a common housing.
Die bekannten Lichtschranken senden einen kontinuierlichen Strahl aus, der im Empfanger ein konstantes empfangenes Signal erzeugt. Sobald die Lichtschranke unterbrochen wird, was durch Abwesenheit des Strahls am Empfanger angezeigt wird, wird ein Signal ausgelost. Die Signale können verschiedenen Zwecken dienen. So kann beispielsweise ein Bereich auf Betreten durch Personen überwacht werden.The known light barriers emit a continuous beam, which generates a constant received signal in the receiver. As soon as the light barrier is interrupted, which is indicated by the absence of the beam at the receiver, a signal is triggered. The signals can serve various purposes. For example, an area can be monitored for people entering it.
Bei den bekannten Lichtschranken kann das Auslosen des Signals verhindert werden, indem der Strahl über Spiegel oder Reflektoren m der Weise zum Empfanger umgelenkt wird, dass ein Korridor geschaffen wird, der einen Zugang ohne Unterbrechung des Strahls der Lichtschranke gestattet .In the known light barriers, the triggering of the signal can be prevented by deflecting the beam via mirrors or reflectors to the receiver in such a way that a corridor is created which allows access without interrupting the light barrier beam.
Es ist deshalb Aufgabe der vorliegenden Erfindung, eine Lichtschranke dahingehend zu verbessern, dass wenigstens eine weitere Eigenschaft des Signals auszuwerten ist.It is therefore the object of the present invention to improve a light barrier in such a way that at least one further property of the signal is to be evaluated.
Diese Aufgabe wird dadurch gelost, dass das Sendesignal moduliert ist. Bei einem modulierten Sendesignal kann neben der reinen Unterbrechung auch wenigstens eine weitere Eigenschaft des Empfangssignals gemessen werden, beispielsweise die Dampfung oder die Phasenlage. Eine Veränderung eines dieser Parameter kann dann auch bei ansonsten nicht unterbrochenem Lichtstrahl zur Entscheidung, ob ein Signal ausgelost werden soll oder nicht, ausgewertet werden.This task is solved by modulating the transmission signal. In the case of a modulated transmission signal, in addition to the mere interruption, at least one further property of the reception signal can also be measured, for example the attenuation or the phase position. A change in one of these parameters can then be evaluated even in the case of an otherwise uninterrupted light beam in order to decide whether a signal should be triggered or not.
In der Praxis ergeben sich gute Auswerte oglichkeiten für das Sendesignal, wenn dieses gepulst ist. Die Signalpulse können anhand der Laufzeit und der Flankensteilheit oder der Amplitude analysiert werden. Weiter ergibt sich eine wirtschaftliche Ausfuhrungsform, wenn der Sender und der Empfanger auf derselben Seite der Messstrecke angeordnet sind und auf der gegenüberliegenden Seite ein Reflektor vorgesehen ist. Eine zuverlässige Erkennung der Manipulation oder sonstigen Beeinflussung des Sendesignals entlang der Messstrecke ist möglich, wenn das Empfangssignal empfangerseitig als Ist-Signal nach Amplitude und Laufzeit oder nach der Signalform analysiert wird und bei Abweichung des Ist-Signals von wenigstens einem gespeicherten Sollwert ein Signal ausgelost wird. Wenn der Sollwert wahrend des Betriebes mit einer gegenüber einer zu erwartenden Störung langen Zeitkonstanten anhand des Ist-Signals geändert wird, kann Änderungen oder Schwankungen im Bereich der Lichtschranke Rechnung getragen werden. So kann beispielsweise das Sollsignal bei nachlassender Wirksamkeit des Senders oder des Empfangers infolge von Alterungsprozessen oder bei allmählicher Verschmutzung der Optik angepasst werden.In practice, there are good evaluation possibilities for the transmission signal when it is pulsed. The signal pulses can be analyzed on the basis of the transit time and the slope or the amplitude. Furthermore, there is an economical embodiment if the transmitter and the receiver are arranged on the same side of the measuring section and a reflector is provided on the opposite side. Reliable detection of the manipulation or other influencing of the transmission signal along the measurement path is possible if the reception signal is analyzed on the receiver side as an actual signal according to amplitude and transit time or according to the signal shape and if the actual signal deviates from at least one stored setpoint, a signal is triggered , If the setpoint is changed during operation with a long time constant based on the actual signal compared to an expected disturbance, changes or fluctuations in the area of the light barrier can be taken into account. For example, the target signal can be adjusted if the effectiveness of the transmitter or receiver declines as a result of aging processes or if the optics gradually become dirty.
Schließlich kann das Sendesignal mit einer Wellenlange im Radarbereich, im Infrarotbereich oder im sichtbaren Bereich ausgesendet werden.Finally, the transmission signal can be emitted with a wavelength in the radar range, in the infrared range or in the visible range.
Die Aufgabe wird außerdem durch ein Verfahren zum Betrieb einer Lichtschranke mit den Merkmalen des Anspruchs 7 gelost .The object is also achieved by a method for operating a light barrier with the features of claim 7.
Weil bei dem erfmdungsgemaßen Verfahren vorgesehen ist, den Signalpuls nach Amplitude und Laufzeit oder nach der Pulsform auszuwerten, fuhren Veränderungen des Lichtstrahls wie z. B. Verkürzungen des Messweges, Verlangerungen des Messweges oder eine Umlenkung zu einem auswertbaren Signal. Eine langsame Anpassung des Sollwertes an unvermeidbare Veränderungen ist möglich, wenn der Sollwert laufend als gleitender Durchscnnitt einer Vielzahl von zuvor gemessenen Ist-Werten aktualisiert wird.Because it is provided in the method according to the invention to evaluate the signal pulse according to amplitude and transit time or according to the pulse shape, changes in the light beam such as e.g. B. Shortening the measuring path, lengthening the measuring path or a redirection to one evaluable signal. A slow adjustment of the setpoint to unavoidable changes is possible if the setpoint is continuously updated as a moving average of a large number of previously measured actual values.
Wenn bei einer Abweichung eines bestimmtenIf there is a deviation from a certain
Signalparameters vom Sollwert ein anders Signal ausgelost wird als bei einer Abweichung eines anderen Parameters, können verschiedene Arten der Beeinflussung des Messwertes unterschieden werden. So kann z. B. zwischen einer Manipulation und einer vollständigen Unterbrechung des Lichtstrahls unterschieden werden.If the signal parameters are drawn from the setpoint differently than when there is a deviation from another parameter, different types of influencing the measured value can be distinguished. So z. B. be distinguished between manipulation and a complete interruption of the light beam.
Im folgenden wir ein Ausfuhrungsbeispiel der vorliegenden Erfindung anhand der Zeichnung beschrieben.In the following we will describe an exemplary embodiment of the present invention with reference to the drawing.
Es zeigen:Show it:
Figur 1: Eine Lichtschranke in einer Prinzipdarsrellung;Figure 1: A light barrier in a principle representation;
Figur 2: ein Messsignal mit gegenüber demFigure 2: a measurement signal compared to
Referenzsignal verminderter Amplitude; sowieReduced amplitude reference signal; such as
Figur 3: ein Messsignal mit gegenüber demFigure 3: a measurement signal compared to
Referenzsignal geänderter Laufzeit.Reference signal changed runtime.
In der Figur 1 ist eine Lichtschranke mit einer Sende- /Empfangsemheit 1 und einem beabstandet hiervon angeordneten Reflektor 2 veranschaulicht. Die Sende- und Empfangseinheit 1 umfasst einen Sender 3 mit nicht naher dargestellten Strahlerzeugungsmitteln, beispielsweise einer Laserdiode und einer entsprechenden strahlformenden Optik. Weiter ist in der Sende- und Empfangseinheit 1 ein Empfanger 4 vorgesehen, der einen ebenfalls nicht naher dargestellten Detektor für Sendesignale enthalt, beispielsweise in Form einer Optik und einer Fotodiode. Schließlich enthalt die Sende- und Empfangseinheit 1 noch eine elektronische Steuerung 5, die zur Ansteuerung der Sendeeinheit 3 und der Empfangseinheit 4 sowie zur externen Signalabgabe eingerichtet ist.A light barrier with a transmitting / receiving unit 1 and a reflector 2 arranged at a distance therefrom is illustrated in FIG. The transmitting and receiving unit 1 comprises a transmitter 3 with beam generating means, not shown, for example a laser diode and a corresponding beam-shaping optics. Furthermore, a receiver 4 is provided in the transmitting and receiving unit 1, which is also not closer to one contains the detector shown for transmission signals, for example in the form of an optic and a photodiode. Finally, the transmitting and receiving unit 1 also contains an electronic controller 5, which is set up to control the transmitting unit 3 and the receiving unit 4 and for external signal output.
Die Sendeeinheit 3 erzeugt einen Lichtstrahl 6, der auf den gegenüberliegenden Retroreflektor 2 gerichtet ist. Dieser reflektiert den Lichtstrahl 6 m der Praxis etwa parallel entlang der Linie 6Λ zurück auf die Empfangseinheit 4, wo der Lichtstrahl empfangen und ausgewertet wird. Die Sende- und Empfangseinheit 1 und der Reflektor 2 begrenzen zwischen sich einen zu überwachenden Bereich, wahrend die Lichtstrahlen 6 und 6Λ den Messweg darstellen.The transmission unit 3 generates a light beam 6, which is directed onto the opposite retroreflector 2. In practice this reflects the light beam 6 m approximately parallel along the line 6 Λ back to the receiving unit 4, where the light beam is received and evaluated. The transmitting and receiving unit 1 and the reflector 2 define between them a 6 and 6 Λ represent the monitored area, while the light beams to the measurement path.
Die Figur 2 zeigt zwei mit der Empfangseinheit 3 aufgezeichnete Signale in einer Darstellung, m der die X-Achse die Zeit darstellt und die Y-Achse die gemessene Intensität. Die Figur 2 zeigt ein Signal 10 mit größerer Amplitude sowie ein Signal 11 mit geringerer Amplitude. Die Laufzeit der beiden Signale ist identisch. Das Signal 10 stellt dabei das ungestörte Signal oder den Sollwert eines von der Sendeeinheit 3 ausgesendeten, am Reflektor 2 reflektierten und in der Empfangseinheit 4 registrierten gepulsten Sendesignals dar. Das Signal 11 ist demgegenüber gedampft, was bei unveränderter Lange des Messweges 6, 6λ für einen Eingriff m die Ubertragungseigenschaften entlang des Signalweges spricht. Beispielsweise kann dieses Signal durch Rauch erzeugt werden. In αer Figur 3 ist schließlich eine Darstellung entsprechend Figur 2 gewählt, m der ein Sollsignal 12 und ein Ist-Signal 13 dargestellt sind. Das Ist-Signal 13 weist gegenüber dem Signal 12 eine geringere Laufzeit zwischen der Sendeeinheit 3 und der Empfangseinheit 4 auf. Dieses Signal 12 spricht dafür, dass bei seiner Messung der Messweg 6, 6 λ verkürzt war.FIG. 2 shows two signals recorded with the receiving unit 3, in which the X-axis represents the time and the Y-axis the measured intensity. FIG. 2 shows a signal 10 with a larger amplitude and a signal 11 with a lower amplitude. The runtime of the two signals is identical. The signal 10 represents the undisturbed signal or the desired value of a pulsed transmission signal emitted by the transmission unit 3, reflected on the reflector 2 and registered in the reception unit 4. The signal 11, in contrast, is attenuated, which with unchanged length of the measurement path 6, 6 λ for an intervention m speaks the transmission properties along the signal path. For example, this signal can be generated by smoke. Finally, a representation corresponding to FIG. 2 is selected in FIG. 3, in which a desired signal 12 and an actual signal 13 are shown. The actual signal 13 has a shorter transit time between the transmitting unit 3 and the receiving unit 4 compared to the signal 12. This signal 12 indicates that the measurement path 6, 6 λ was shortened when it was measured.
In der Praxis wird von der Sende- und Empfangseinheit 1 über die Steuerung 5 und die Sendeeinheit 3 ein gepulstes Sendesignal mit einer bestimmten Pulsdauer und Pulsamplitude ausgesendet. Dieses Signal wird bei ungestörtem Messweg 6, 6Λ am Reflektor 2 reflektiert und im Empfanger 4 aufgezeichnet. Dieses Signal wird m der Steuerung 5 als Sollsignal gespeichert und entspricht in den Figuren 2 und 3 den Signalen 10 bzw. 12.In practice, the transmission and reception unit 1 sends out a pulsed transmission signal with a specific pulse duration and pulse amplitude via the controller 5 and the transmission unit 3. With undisturbed measuring path 6, 6 Λ, this signal is reflected at the reflector 2 and recorded in the receiver 4. This signal is stored in the controller 5 as the desired signal and corresponds to the signals 10 and 12 in FIGS. 2 and 3.
Die Aussendung des gepulsten Signals wird im folgenden Betrieb regelmäßig wiederholt, wobei in der Steuerung 5 das -jeweils empfangene Signal mit dem Sollsignal verglichen wird. Langsame Änderungen durch Alterung der Elektronik, Temperaturschwankungen oder Verschmutzungen der Optik bzw. des Reflektors 2 werden durch Anpassung des Sollsignals mit einer langen Zeitkonstante oder durch Bildung gleitender Durchschnitte adaptiert, ohne dass sie zu einer Alarmauslosung fuhren.The transmission of the pulsed signal is repeated regularly in the following operation, the signal received in the controller 5 being compared with the desired signal. Slow changes due to aging of the electronics, temperature fluctuations or soiling of the optics or the reflector 2 are adapted by adapting the target signal with a long time constant or by forming moving averages without leading to an alarm being triggered.
Wenn im Bereich der überwachten Messstrecke 6, 6 λ das Signal vollständig ausbleibt, wird auf eine Unterbrechung geschlossen und wie bei einer herkömmlichen Lichtschranke ein Alarmsignal ausgelost. Wenn die Übertragung des Sendesignals mit erhöhter Dampfung erfolgt, also eine geringere Amplitude wie m der Figur 2 im Signal 11 vorliegt, kann darauf geschlossen werden, dass Rauch in den Signalweg eingedrungen ist. Dieses Signal unveränderter Laufzeit und geringerer Amplitude kann also zur Auslosung eines Feueralarms benutzt werden. Wenn dagegen wie in der Figur 3 das Ist-Signal mit verkürzter Laufzeit gegenüber dem Sollsignal ermittelt wird, so kann darauf geschlossen werden, dass der Messweg 6, 6 durch Einbringen eines anderen Reflektors in den Messweg verkürzt wurde. Eine αerartige Manipulation der Lichtschranke fuhrt ebenso wie eine vollständige Unterbrechung des Senαesignals zur Auslosung eines Signals, das ein unbefugtes Betreten anzeigen kann. If the signal is completely absent in the area of the monitored measuring section 6, 6 λ , an interruption is concluded and an alarm signal is triggered, as in the case of a conventional light barrier. If the transmission of the transmission signal takes place with increased damping, that is to say a smaller amplitude than m in FIG. 2 in signal 11, it can be concluded that smoke in the signal path has penetrated. This signal of unchanged transit time and lower amplitude can therefore be used to trigger a fire alarm. If, on the other hand, as in FIG. 3, the actual signal is determined with a shortened transit time compared to the target signal, it can be concluded that the measurement path 6, 6 has been shortened by introducing another reflector into the measurement path. Aer-like manipulation of the light barrier, like a complete interruption of the sensor signal, leads to the triggering of a signal which can indicate unauthorized entry.

Claims

P a t e n t a n s p r c h e Patent claims
1. Lichtschranke mit einem Sender (3) und einem Empfanger1. Light barrier with a transmitter (3) and a receiver
(4) sowie mit einer zwischen dem Sender (3) und dem Empfanger (4) angeordneten Messstrecke (6, 6 '→ , wobei der Sender (3) ein Sendesignal (10) entlang αer Messstrecke (6,6') zu dem Empfanger (4) sendet und wobei eine elektronische Schaltung (5) zur Uoerwachung des empfangenen Signals (11) vorgesehen ist, d a du r c h ge k e n n z e i c h n e t , dass das Sendesignal (10) moduliert ist.(4) and with a measuring section (6, 6 ' → ) arranged between the transmitter (3) and the receiver (4), the transmitter (3) sending a signal (10) along the measuring section (6,6') to the receiver (4) sends and wherein an electronic circuit (5) for monitoring the received signal (11) is provided, since you rch indicates that the transmission signal (10) is modulated.
2. Lichtschranke nach Anspruch 1, da du r c h g e ke n n z e i c hn e t , dass das Sendesignal (10) gepulst ist.2. Light barrier according to claim 1, since you r c h g e ke n n z e i c hn e t that the transmission signal (10) is pulsed.
3. Lichtschranke nach einem der vorhergehenden Ansprüche, da du r ch g e k e n n z e i ch n e t , dass der Sender (3) und der Empfanger (4) auf derselben Seite der Messstrecke (6,6') angeordnet sind und auf der gegenüberliegenden Seite ein Reflektor (2) vorgesehen3. Light barrier according to one of the preceding claims, since you r ch marked that the transmitter (3) and the receiver (4) are arranged on the same side of the measuring section (6, 6 ') and on the opposite side a reflector ( 2) provided
4. Lichtschranke nach einem der vorhergehenden Ansprüche, d a du r c h g e k e n n z e i c h n e t , dass das Empfangssignal (11) empfangerseitig als Ist-Signal nach Amplitude und Laufzeit analysiert wird und bei Abweichungen des Ist-Signals von wenigstens einem gespeicherten Sollwert ein Signal ausgelost wird.4. Light barrier according to one of the preceding claims, since you rchgek characterized in that the received signal (11) on the receiver side is analyzed as an actual signal according to amplitude and transit time and at Deviations of the actual signal from at least one stored setpoint is triggered a signal.
5. Lichtschranke nach einem der vorhergehenden Ansprüche, da du r c h g e k e n n z e i c h n e t , dass der Sollwert wahrend des Betriebes mit einer gegenüber einer zu erwartenden Störung langen Zeitkonstante anhand des Ist-Signals geändert wird.5. Light barrier according to one of the preceding claims, since you r c h g e k e n n z e i c h n e t that the setpoint is changed during operation with a long time constant compared to an expected disturbance based on the actual signal.
6. Lichtschranke nach einem der vorhergehenden Ansprüche, d a du r c h g e k e n n z e i ch n e t , dass das Sendesignal (10) mit einer Wellenlange im Radarbereich, im Infrarotbereich oder im sichtbaren Bereich ausgesendet wird.6. Light barrier according to one of the preceding claims, that the transmission signal (10) is emitted with a wavelength in the radar range, in the infrared range or in the visible range.
7. Verfahren zum Betrieb einer Lichtschranke mit folgenden Schritten:7. Method for operating a light barrier with the following steps:
Aussenden eines Sendepulses (10) entlang einer zu überwachenden Messstrecke (6,6');Emitting a transmission pulse (10) along a measurement section (6, 6 ') to be monitored;
Empfangen des direkten oder reflektierten Sendepulses am Ende der Messstrecke (6,6') als EmpfangssignalReceiving the direct or reflected transmission pulse at the end of the measuring section (6,6 ') as a reception signal
(11) ; ( 11);
Auswerten des Empfangssignals (11) nach Amplitude und Phase oder Signalform;Evaluating the received signal (11) according to amplitude and phase or signal shape;
Vergleichen der Amplitude und Phase oder der Signalform als Ist-Wert mit einem Sollwert; Auslosen eines Signals bei einer Abweichung des Ist- Werts von dem Sollwert um mehr als eine Toleranz.Comparing the amplitude and phase or the waveform as the actual value with a target value; Triggering a signal when the actual value deviates from the target value by more than a tolerance.
8. Verfahren nach Anspruch 7, da du r ch ge ke n n z e i chn e t , dass der Sollwert laufend als gleitender Durchschnitt einer Vielzahl von zuvor gemessenen Ist-Werten aktualisiert wird. Verfahren nach einem der vorhergehenden Ansprüche, d a du r c h ge k e nn z e i c h n e t , dass bei einer Abweichung eines ausgewählten Signalparameters vom Sollwert je nach Art des Parameters ein anderes Signal ausgelost wird. 8. The method according to claim 7, since you r ch ge k nnnzei chn et that the setpoint is continuously updated as a moving average of a plurality of previously measured actual values. Method according to one of the preceding claims, since you can see that if a selected signal parameter deviates from the target value, a different signal is triggered depending on the type of parameter.
PCT/EP2000/005748 1999-11-10 2000-06-21 Photoelectric barrier WO2001035362A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU54061/00A AU5406100A (en) 1999-11-10 2000-06-21 Photoelectric barrier

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19954156A DE19954156A1 (en) 1999-11-10 1999-11-10 Photoelectric barrier
DE19954156.6 1999-11-10

Publications (1)

Publication Number Publication Date
WO2001035362A1 true WO2001035362A1 (en) 2001-05-17

Family

ID=7928610

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2000/005748 WO2001035362A1 (en) 1999-11-10 2000-06-21 Photoelectric barrier

Country Status (3)

Country Link
AU (1) AU5406100A (en)
DE (1) DE19954156A1 (en)
WO (1) WO2001035362A1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102004047911B4 (en) * 2004-09-29 2007-06-06 Magna Car Top Systems Gmbh Collision protection device for a storage compartment for an openable vehicle roof
JP2006145483A (en) * 2004-11-24 2006-06-08 Sharp Corp Pulse modulation type photodetection system, electronic equipment, and pulse modulation type photodetection method

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4356393A (en) * 1980-05-29 1982-10-26 Banner Engineering Corp. Alignment indicator for photoelectric scanners
US4742337A (en) * 1985-08-28 1988-05-03 Telenot Electronic Gmbh Light-curtain area security system
US4879461A (en) * 1988-04-25 1989-11-07 Harald Philipp Energy field sensor using summing means

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2059656A1 (en) * 1970-12-04 1972-06-29 Alfons Endl Light barrier with a circuit to keep the control shaft constant
DE4119797C2 (en) * 1991-06-15 1994-02-24 Leuze Electronic Gmbh & Co A transmitter, a receiver and a circuit arrangement for signal evaluation monitoring device
US5336882A (en) * 1992-12-30 1994-08-09 Allen-Bradley Company, Inc. System for determining operational stability of a photoelectric control unit having a margin variable gain module
DE19517001A1 (en) * 1995-05-09 1996-11-14 Sick Optik Elektronik Erwin Method and device for determining the light propagation time over a measuring section arranged between a measuring device and a reflecting object
DE19621120C1 (en) * 1996-05-24 1997-05-07 Leuze Electronic Gmbh & Co Opto electronic device for detecting object in security zone
DE19644791C2 (en) * 1996-10-28 2002-11-28 Sick Ag Method and device for determining the light propagation time over a measuring section arranged between a measuring device and a reflecting object
DE19718391A1 (en) * 1997-04-30 1998-11-05 Sick Ag Method for operating an opto-electronic sensor
DE19729638A1 (en) * 1997-07-10 1999-01-14 Sick Ag Method for operating an opto-electronic sensor

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4356393A (en) * 1980-05-29 1982-10-26 Banner Engineering Corp. Alignment indicator for photoelectric scanners
US4742337A (en) * 1985-08-28 1988-05-03 Telenot Electronic Gmbh Light-curtain area security system
US4879461A (en) * 1988-04-25 1989-11-07 Harald Philipp Energy field sensor using summing means

Also Published As

Publication number Publication date
DE19954156A1 (en) 2001-05-17
AU5406100A (en) 2001-06-06

Similar Documents

Publication Publication Date Title
DE3514982C2 (en)
EP0066889B1 (en) Dynamic range control device for a distance measuring equipment
EP1723446B1 (en) Access control device
EP3525004B1 (en) Tof sensor with test transmitter
DE4312186C2 (en) Methods and devices for determining objects present in a surveillance area and / or for determining their position
EP1239300A2 (en) Device fro determination of a distance profile
EP0742450A2 (en) Method and apparatus for measuring the time for light to travel a measurement path extending between a measurement apparatus and a reflecting object
WO2014048663A1 (en) Fill level measurement device
DE19828000C2 (en) Method for optoelectronic monitoring of a protected area
DE4215272A1 (en) Transmitter, receiver and circuit for photoelectric intruder detection - evaluates time difference between zero-crossings of signals from photodetector output shaper and modulation-oscillator-driven Schmitt trigger
DE19951557B4 (en) Optoelectronic device
EP1522879B1 (en) Opto-electronic sensor and method of detecting an object in a surveillance area
DE19749397B4 (en) Viewing distance sensor
DE3219452C2 (en) Dynamics control arrangement for a distance measuring device
DE10202305B4 (en) Optical sensor
WO2001035362A1 (en) Photoelectric barrier
EP1780559B1 (en) Optical sensor
DE10018948B4 (en) Optoelectronic device
EP0569686B1 (en) Surveillance apparatus comprising transmitter, receiver and signal processing circuit
EP0857982B1 (en) Method and device for distance determination between vehicle and obstacle
DE19917487B4 (en) Optoelectronic device
EP3070496A1 (en) Polygon scanner and method for recording objects
DE19936441C2 (en) Optoelectronic device
EP2634598B1 (en) Optical sensor
DE102011001713B3 (en) Device for transmission of information to selected objects of scanning shot simulation system in solid angle range, has transmission unit together with receiver unit for determining location of objects in solid angle range

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AU CN JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE

121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP