DE3532199A1 - Sensor for controlling the visual clarity of panes of glass - Google Patents

Sensor for controlling the visual clarity of panes of glass

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Publication number
DE3532199A1
DE3532199A1 DE19853532199 DE3532199A DE3532199A1 DE 3532199 A1 DE3532199 A1 DE 3532199A1 DE 19853532199 DE19853532199 DE 19853532199 DE 3532199 A DE3532199 A DE 3532199A DE 3532199 A1 DE3532199 A1 DE 3532199A1
Authority
DE
Germany
Prior art keywords
pane
sensor according
total reflection
glass
transparency
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.)
Withdrawn
Application number
DE19853532199
Other languages
German (de)
Inventor
Lorenz Dr Twisselmann
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
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 Individual filed Critical Individual
Priority to DE19853532199 priority Critical patent/DE3532199A1/en
Publication of DE3532199A1 publication Critical patent/DE3532199A1/en
Withdrawn legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60S—SERVICING, CLEANING, REPAIRING, SUPPORTING, LIFTING, OR MANOEUVRING OF VEHICLES, NOT OTHERWISE PROVIDED FOR
    • B60S1/00—Cleaning of vehicles
    • B60S1/02—Cleaning windscreens, windows or optical devices
    • B60S1/04—Wipers or the like, e.g. scrapers
    • B60S1/06—Wipers or the like, e.g. scrapers characterised by the drive
    • B60S1/08—Wipers or the like, e.g. scrapers characterised by the drive electrically driven
    • B60S1/0818—Wipers or the like, e.g. scrapers characterised by the drive electrically driven including control systems responsive to external conditions, e.g. by detection of moisture, dirt or the like
    • B60S1/0822—Wipers or the like, e.g. scrapers characterised by the drive electrically driven including control systems responsive to external conditions, e.g. by detection of moisture, dirt or the like characterized by the arrangement or type of detection means
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60S—SERVICING, CLEANING, REPAIRING, SUPPORTING, LIFTING, OR MANOEUVRING OF VEHICLES, NOT OTHERWISE PROVIDED FOR
    • B60S1/00—Cleaning of vehicles
    • B60S1/02—Cleaning windscreens, windows or optical devices
    • B60S1/04—Wipers or the like, e.g. scrapers
    • B60S1/06—Wipers or the like, e.g. scrapers characterised by the drive
    • B60S1/08—Wipers or the like, e.g. scrapers characterised by the drive electrically driven
    • B60S1/0818—Wipers or the like, e.g. scrapers characterised by the drive electrically driven including control systems responsive to external conditions, e.g. by detection of moisture, dirt or the like
    • B60S1/0822—Wipers or the like, e.g. scrapers characterised by the drive electrically driven including control systems responsive to external conditions, e.g. by detection of moisture, dirt or the like characterized by the arrangement or type of detection means
    • B60S1/0833—Optical rain sensor
    • B60S1/0837—Optical rain sensor with a particular arrangement of the optical elements
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/41—Refractivity; Phase-affecting properties, e.g. optical path length
    • G01N21/43—Refractivity; Phase-affecting properties, e.g. optical path length by measuring critical angle

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  • Engineering & Computer Science (AREA)
  • Automation & Control Theory (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)

Abstract

A sensor is described which uses the disturbance of total reflection of a light beam by water droplets on a pane of glass, which light beam is reflected a plurality of times in the pane of glass. The attenuation of the light transmission through the pane of glass from a transmitter to a receiver is a measure of the visual clarity and is used to maintain said visual clarity at a desired level, for example by initiating wiping processes. Said sensor is suitable for use, inter alia, in a motor vehicle.

Description

Besonders in Fahrzeugen werden Wischer eingesetzt, die bei Regen die klare Sicht durch vor allem Frontscheiben möglich machen sollen. Bei verschieden starkem Regen sind Inter­ vallschaltungen bekannt oder man läßt die Wischer mit verschiedener Geschwindigkeit arbeiten. Bei diesen Maßnahmen handelt es sich um Steuerungen, bei denen der Mensch (Fahrer) die Notwendigkeit einer Anderung erkennen und auch ausführen muß.Wipers are used in vehicles in particular Rain clear view possible especially through front windows should do. If the rain is different, inter vall circuits known or let the wiper work at different speeds. With these measures are controls in which humans (Driver) recognize the need for change and must also execute.

Der Erfindungsgegenstand kann den Menschen (Fahrer) bei diesem Vorgang stark entlasten. Die Durchsichtigkeit der Scheibe wird von einem Sensor gemessen und der Meßwert mit einem Sollwert verglichen. In bekannter Weise wird bei Unterschreiten des Sollwertes über eine Reglerschaltung der Scheibenwischerantrieb angesteuert und somit ein Regelkreis geschlossen. Der Wischer wischt solange, bis eine klare Sicht wiederhergestellt ist und gleich­ zeitig so schnell oder in solchen Abständen, daß eine ausreichende Durchsicht erhalten bleibt. Mit Verstellung des Sollwertes kann die Qualität "ausreichende Durch­ sicht" verändert werden.The subject of the invention can help people (drivers) greatly relieve this process. The transparency of the Disc is measured by a sensor and the measured value compared with a target value. In a known manner Falling below the setpoint via a controller circuit the windshield wiper drive is activated and thus on Closed loop. The wiper wipes until a clear view is restored and the same early enough or at such intervals that a sufficient transparency is maintained. With adjustment of the target value, the quality "sufficient through view "can be changed.

Es sind Anwendungen der Störung von Totalreflexion in der Technik bei der Füllstandsmessung bekannt (Naumann/ Schröder, Bauelemente der Optik, Carl Hanser Verlag München 1983). Dabei wird wie in der Erfindung die Aus­ koppelung eines Lichtbündels aus einem total reflektie­ renden Glas oder glasähnlichem Körper durch Flüssigkeit verwendet.There are applications of interference from total reflection in the technology for level measurement (Naumann / Schröder, components of optics, Carl Hanser Verlag Munich 1983). Here, as in the invention, the end coupling a light beam from a total reflection liquid or glass-like body used.

Die Erweiterung der bekannten Technik durch die Erfindung besteht darin, daß zu dieser Auskoppelung Flüssigkeits­ tropfen führen und daß die Störung der Totalreflexion an einer Glas oder glasähnlichen Scheibe als Sensorsignal für die Durchsichtigkeit derScheibe verwendet wird. The invention extends the known technology consists in the fact that this decoupling fluid cause drip and that the disturbance of total reflection a glass or glass-like pane as a sensor signal is used for the transparency of the pane.  

Der Sensor wird auf der Innenseite der Glasscheibe (1) im Wischerbereich angebracht. Mit einem Prisma (2) wird sichtbares oder infrarotes Licht aus einem Sender (3) (LED, IR-Diode) unter einem mittleren Winkel ε in die Glasscheibe eingestrahlt. Der Einstrahlwinkel ε liegt zwischen dem Grenzwinkel der Totalreflexion Glas/Luft und dem Grenz­ winkel der Totalreflexion Glas/Wasser. Dadurch wird das Lichtbündel in bekannter Weise an den Flächen Glas/Luft total reflektiert und gelangt über ein zweites Prisma (2) zu einem Empfänger (4).The sensor is attached to the inside of the glass pane ( 1 ) in the wiper area. With a prism ( 2 ), visible or infrared light from a transmitter ( 3 ) (LED, IR diode) is radiated into the glass pane at an average angle ε . The angle of incidence ε lies between the critical angle of the total reflection glass / air and the critical angle of the total reflection glass / water. As a result, the light beam is totally reflected in a known manner on the glass / air surfaces and reaches a receiver ( 4 ) via a second prism ( 2 ).

Das Licht zwischen Sender und Empfänger ist zweckmäßiger­ weise zu modulieren, um Fremdlichteinflüsse zu eliminieren. Befinden sich auf einer Seite der Glasplatte Wassertropfen (5); (6), so wird hier die Totalreflexion gestört. Bei einer gewissen Dichte von Tropfen wird das empfangene Signal an (4) so klein, daß ein in einer Regelschaltung eingestellter Sollwert unterschritten und der Wischer eingeschaltet wird. Ist die Scheibe so sauber gewischt, daß wieder klare Durchsicht gegeben ist, tritt die Totalreflexion wieder ein und der Wischvorgang wird beendet.The light between the transmitter and receiver should be modulated appropriately in order to eliminate the effects of extraneous light. There are water drops ( 5 ) on one side of the glass plate; ( 6 ), the total reflection is disturbed here. With a certain density of drops, the received signal at ( 4 ) becomes so small that the value falls below a setpoint set in a control circuit and the wiper is switched on. If the window is wiped so clean that there is a clear view again, the total reflection occurs again and the wiping process is ended.

Die Ansprechschwelle der Anordnung kann zum einen durch Verändern des Sollwertes geändert werden, zum anderen hängt sie von der Breite des Lichtbündels sowie vor allem von der Zahl der Reflexionen in der Glasscheibe, also vom Verhältnis der Glasdicke zum Abstand von Sender und Empfänger ab. Sender und Empfänger können an der Glasschei­ be in größerem Abstand angebracht werden, da mit einem modulierten Signal eine hohe Verstärkung des Empfangssignals möglich ist.The response threshold of the arrangement can be Changing the setpoint to be changed, secondly it depends on the width of the light beam as well as most of all on the number of reflections in the glass pane, so of the ratio of the glass thickness to the distance from the transmitter and Recipient. Transmitter and receiver can on the glass be attached at a greater distance because with a modulated signal a high gain of the received signal is possible.

Um den Sensor gegen Beschlag von der Innenseite, wodurch die Totalreflexion ebenfalls aufgehoben wird, zu schützen, kann die Glasfläche zwischen Sender und Empfänger mit einer Abdeckung (7) versehen werden. In order to protect the sensor against fogging from the inside, which also eliminates the total reflection, the glass surface between the transmitter and receiver can be provided with a cover ( 7 ).

Grundsätzlich ist auch eine Anordnung nach Skizze 2 denkbar, bei der ein einziges Glasprisma zum Ein- und Auskoppeln des Lichtbündels dient. Die Anordnung nach Skizze 1 kann jedoch vorteilhaft auch an gekrümmten Scheiben verwendet werden.In principle, an arrangement according to sketch 2 is also conceivable, in which a single glass prism for coupling and decoupling the Light beam is used. The arrangement according to sketch 1 can, however can also be used advantageously on curved panes.

Da nicht nur Wassertropfen die Totalreflexion stören, sondern auch Festkörper, wie Staub und Insektenreste, wie sie jedem Autofahrer bekannt sind, läßt sich dieser Sensor in Verbin­ dung mit einem Feuchtefühler auch zum automatisierten Waschen von Sichtscheiben einsetzen.Because not only water drops interfere with total reflection, but also solids, like dust and insect remains, like everyone Motorists are known, this sensor can be connected with a humidity sensor also for automated Use the lens to wash it.

Claims (9)

1. Sensor zur Regelung der Durchsichtigkeit von Glas- oder glasähnlichen Scheiben bei Regen oder Spritzwasser, dadurch gekennzeichnet, daß die Störung der Totalreflexion von einem in der Scheibe mehrfach total reflektierten Lichtbündel ausgenutzt wird.1. Sensor for regulating the transparency of glass or glass-like panes in the event of rain or splashing water, characterized in that the disturbance of the total reflection is exploited by a light bundle which is totally totally reflected in the pane. 2. Sensor nach Anspruch 1, dadurch gekennzeichnet, daß in die durchsichtige Scheibe ein Lichtbündel unter einem mittleren Winkel ε eingestrahlt wird, der zwischen dem Grenzwinkel der Totalreflexion Scheibe/Luft und dem Grenz­ winkel der Totalreflexion Scheibe/Wasser liegt.2. Sensor according to claim 1, characterized in that in the transparent pane is a light beam under one average angle ε is radiated between the Limit angle of total reflection disc / air and the limit angle of total reflection disk / water. 3. Sensor nach Anspruch 2, dadurch gekennzeichnet, daß das in der Scheibe an den Grenzflächen zur Luft mehrfach total­ reflektierte Lichtbündel mit einem geeignet geformten z.B. prismatischen Körper aus der Scheibe herausgelenkt und auf ein lichtemfindliches elektrisches Element geführt wird, mit dem ein elektrisches Signal gewonnen wird.3. Sensor according to claim 2, characterized in that the in the disk at the interfaces with the air several times totally reflected light bundles with a suitably shaped e.g. prismatic body deflected out of the disc and led to a light-sensitive electrical element with which an electrical signal is obtained. 4. Sensor nach Anspruch 2, dadurch gekennzeichnet, daß das in die Scheibe eingestrahlte Licht sichtbares oder infrarotes Licht mit einer Amplituden- oder phasenmodula­ tion ist.4. Sensor according to claim 2, characterized in that the light shining into the pane is visible or infrared light with an amplitude or phase module tion is. 5. Sensor nach Anspruch 3 und 4, dadurch gekennzeichnet, daß das modulierte elektrische Signal aus dem lichtempfind­ lichen Element hoch verstärkt werden kann und als ein Meßsignal zur Verfügung steht, das von der Störung der Totalreflexion an den Grenzflächen der Scheibe, insbesondere der äußeren Grenzfläche, abhängig ist.5. Sensor according to claim 3 and 4, characterized in that the modulated electrical signal from the photosensitive element can be highly reinforced and as a Measurement signal is available, which from the disturbance of the Total reflection at the interfaces of the pane, especially the outer interface. 6. Sensor nach Anspruch 5, dadurch gekennzeichnet, daß das Meßsignal gleichzeitig ein Maß für die Störung der Total­ reflexion und für die Durchsichtigkeit der Scheibe ist, wenn sich Wassertropfen auf ihrer Oberfläche befinden.6. Sensor according to claim 5, characterized in that the Measurement signal at the same time a measure of the disturbance of the total reflection and for the transparency of the pane, if there are drops of water on their surface. 7. Sensor nach Anspruch 6, dadurch gekennzeichnet, daß das Meßsignal für die Durchsichtigkeit in einem Regler mit einem einstellbaren Sollwert verglichen wird und der Regler entsprechend der Regelabweichung ein Stellsignal betätigt, das aus einem Wischer bestehen kann, und mit diesem die Durchsichtigkeit der Scheibe als Regelgröße auf einem dem Sollwert entsprechenden Maß hält. 7. Sensor according to claim 6, characterized in that the Measurement signal for transparency in a controller with an adjustable setpoint is compared and the controller actuates a control signal according to the control deviation, that can consist of a wiper, and with this the Transparency of the pane as a control variable on one keeps the measure corresponding to the target value.   8. Sensor nach Anspruch 7, dadurch gekennzeichnet, daß die Innenseite der Scheibe gegen Feuchtigkeitsbeschlag geschützt ist, was durch Abdecken mit einem Gehäuse möglich ist, oder daß der Beschlag unwirksam gemacht wird durch Ver­ spiegeln der Innenfläche.8. Sensor according to claim 7, characterized in that the The inside of the pane is protected against moisture is what is possible by covering it with a case, or that the fitting is rendered ineffective by Ver reflect the inner surface. 9. Sensor nach Anspruch 7, dadurch gekennzeichnet, daß die Durchsichtigkeit einer Frontscheibe in einem Verkehrs­ mittel (Auto, Bahn, Schiff, Flugzeug) erhalten bleibt.9. Sensor according to claim 7, characterized in that the transparency of a windscreen in traffic medium (car, train, ship, plane) is preserved.
DE19853532199 1985-09-10 1985-09-10 Sensor for controlling the visual clarity of panes of glass Withdrawn DE3532199A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE19853532199 DE3532199A1 (en) 1985-09-10 1985-09-10 Sensor for controlling the visual clarity of panes of glass

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Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3926228A1 (en) * 1988-08-11 1990-02-15 Fujitsu Ten Ltd RAIN SENSOR
DE4006174C1 (en) * 1990-02-28 1991-07-25 Leopold Kostal Gmbh & Co Kg, 5880 Luedenscheid, De
DE4134432A1 (en) * 1991-10-18 1993-04-22 Daimler Benz Ag METHOD FOR ADAPTING THE RESPONSE SENSITIVITY OF A REPUTATION SENSOR SYSTEM TO ENVIRONMENTAL CONDITIONS AND SENSOR SYSTEM WITH A DEPOSITION SENSOR
DE4300741A1 (en) * 1993-01-14 1994-07-21 Kostal Leopold Gmbh & Co Kg Sensor arrangement for detecting degree of moisture on transparent screen caused by precipitation
US5391891A (en) * 1990-02-28 1995-02-21 Leopold Kostal Gmbh & Co. Kg Moisture sensing device
WO1995023082A1 (en) * 1994-02-26 1995-08-31 Robert Bosch Gmbh Rain sensor
DE19837050A1 (en) * 1998-08-17 2000-02-24 Gardena Kress & Kastner Gmbh Liquid detection device
WO2002004248A1 (en) * 2000-07-11 2002-01-17 Leopold Kostal Gmbh & Co. Kg Device and method for automatically adapting a light sensor to a windscreen
DE4337835B4 (en) * 1993-11-05 2008-05-15 Valeo Schalter Und Sensoren Gmbh measuring device
DE102011003803A1 (en) 2011-02-08 2012-08-09 Robert Bosch Gmbh Method and device for determining a clarity of a pane of a vehicle
DE102014004451A1 (en) 2014-03-27 2015-10-01 Hella Kgaa Hueck & Co. Method and sensor unit for detecting a degree of wetting of a pane
CN112213286A (en) * 2020-10-13 2021-01-12 广州新程北斗信息科技有限公司 Vehicle-mounted data acquisition sensor

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3926228A1 (en) * 1988-08-11 1990-02-15 Fujitsu Ten Ltd RAIN SENSOR
DE4006174C1 (en) * 1990-02-28 1991-07-25 Leopold Kostal Gmbh & Co Kg, 5880 Luedenscheid, De
US5391891A (en) * 1990-02-28 1995-02-21 Leopold Kostal Gmbh & Co. Kg Moisture sensing device
DE4134432A1 (en) * 1991-10-18 1993-04-22 Daimler Benz Ag METHOD FOR ADAPTING THE RESPONSE SENSITIVITY OF A REPUTATION SENSOR SYSTEM TO ENVIRONMENTAL CONDITIONS AND SENSOR SYSTEM WITH A DEPOSITION SENSOR
DE4300741A1 (en) * 1993-01-14 1994-07-21 Kostal Leopold Gmbh & Co Kg Sensor arrangement for detecting degree of moisture on transparent screen caused by precipitation
DE4300741C2 (en) * 1993-01-14 1998-02-19 Kostal Leopold Gmbh & Co Kg Sensor device
DE4337835B4 (en) * 1993-11-05 2008-05-15 Valeo Schalter Und Sensoren Gmbh measuring device
CN1046670C (en) * 1994-02-26 1999-11-24 罗伯特·博施有限公司 Rain sensor
US5811793A (en) * 1994-02-26 1998-09-22 Robert Bosch Gmbh Rain sensor for glass shut
WO1995023082A1 (en) * 1994-02-26 1995-08-31 Robert Bosch Gmbh Rain sensor
DE19837050A1 (en) * 1998-08-17 2000-02-24 Gardena Kress & Kastner Gmbh Liquid detection device
US6365908B1 (en) 1998-08-17 2002-04-02 Gardena Kress + Kastner Gmbh Indicator for indicating the presence of a liquid
WO2002004248A1 (en) * 2000-07-11 2002-01-17 Leopold Kostal Gmbh & Co. Kg Device and method for automatically adapting a light sensor to a windscreen
US6559466B2 (en) 2000-07-11 2003-05-06 Leopold Kostal Gmbh & Co. Device and method for automatically adapting a light sensor to a windscreen
DE102011003803A1 (en) 2011-02-08 2012-08-09 Robert Bosch Gmbh Method and device for determining a clarity of a pane of a vehicle
WO2012107136A1 (en) 2011-02-08 2012-08-16 Robert Bosch Gmbh Method and device for determining an optical clarity through a car window
DE102014004451A1 (en) 2014-03-27 2015-10-01 Hella Kgaa Hueck & Co. Method and sensor unit for detecting a degree of wetting of a pane
US9377402B2 (en) 2014-03-27 2016-06-28 Hella Kgaa Hueck & Co. Method and sensor unit for detecting a degree of wetting of a glass pane
CN112213286A (en) * 2020-10-13 2021-01-12 广州新程北斗信息科技有限公司 Vehicle-mounted data acquisition sensor

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