Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60J—WINDOWS, WINDSCREENS, NON-FIXED ROOFS, DOORS, OR SIMILAR DEVICES FOR VEHICLES; REMOVABLE EXTERNAL PROTECTIVE COVERINGS SPECIALLY ADAPTED FOR VEHICLES
  • B60J3/00—Antiglare equipment associated with windows or windscreens; Sun visors for vehicles
  • B60J3/04—Antiglare equipment associated with windows or windscreens; Sun visors for vehicles adjustable in transparency
• • G—PHYSICS
  • G02—OPTICS
  • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
  • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
  • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
  • G02F1/15—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on an electrochromic effect
  • G02F1/163—Operation of electrochromic cells, e.g. electrodeposition cells; Circuit arrangements therefor

Definitions

• the present invention relates to a method and a device for managing the power supply of an electrochromic glass roof panel for a motor vehicle.
• Some motor vehicles have a roof equipped with a glass panel to increase the brightness inside the vehicle.
• the glass panel can be obscured by a sliding sunshade.
• electrochromic glass panels are described for example in US6501457. These electrochromic glass panels have the property of being able to transmit more or less light according to the transparency or opacity desired by the user. Such panels become opaque for example to protect themselves against the sun by feeding the panel with electrical pulses whose amplitude can adjust the desired transmission rate.
• a computer is used for this purpose which is powered by the battery of the motor vehicle and which is programmed to supply the electrochromic glass roof panel with electrical pulse trains, each pulse train having pulses having a constant amplitude and a period, the duration and / or amplitude of the pulses in different pulse trains being adjustable over time depending on the desired light transmission rate.
• the electrochromic roof is permanently powered, which strongly demands the battery of the vehicle.
• the roof has a reduced surface and the battery has sufficient capacity.
• the applicant has planned to limit the duration of power of the roof panel to a maximum duration, for example eight hours, to avoid the discharge of the battery.
• This battery is indeed solicited not only during the duration of application of the electrical pulses necessary to opacify the roof panel, but also during other periods during which only the computer is powered.
• the object of the present invention is to overcome this drawback by proposing a method and a device for better managing the power supply of an electrochromic glass roof panel of a motor vehicle.
• the method for managing the power supply of an electrochromic glass roof panel for a motor vehicle in which a computer is used which is powered by the vehicle battery and which is programmed to power the control panel.
• roof by electric pulse trains each electrical pulse train having pulses having a constant amplitude and a period, the amplitude and / or the duration of the pulses in different pulse trains being adjustable according to the transmission rate of desired light, these electrical pulse trains being maintained for a predetermined maximum duration to prevent the discharge of the battery and followed by a period during which only the computer is powered, is characterized in that the power supply of the computer is disconnected from the battery when the ambient brightness falls below a predetermined threshold.
• the device for managing the power supply of an electrochromic glass roof panel for a motor vehicle comprising a computer which is powered by the vehicle battery and which is programmed to supply the roof panel with electric pulse trains, each electrical pulse train having pulses having a constant amplitude and a period, the amplitude and / or the duration of the pulses in different pulse trains being adjustable according to the desired light transmission rate, and to maintain these electrical pulse trains for a predetermined maximum duration to avoid discharge of the battery, these electrical pulse trains being followed by a period of time which only the computer is powered, is characterized in that it comprises a sensor for detecting the intensity of the ambient brightness, the computer having means programmed to disconnect its power supply from the battery when said sensor detects that the intensity of the brightness falls below a predetermined threshold. This predetermined threshold may correspond to the fall of the day.
• the brightness sensor is preferably located in the passenger compartment of the vehicle.
• the management device further comprises an external temperature sensor cooperating with said computer to optimize the amplitude and / or the duration of said pulses in said current pulse trains.
• the device further comprises a control button located inside the motor vehicle for adjusting the amplitude and / or the duration of the pulses in the electric pulse trains as a function of the desired light transmission rate of the control panel.
• electrochromic glass roof located inside the motor vehicle for adjusting the amplitude and / or the duration of the pulses in the electric pulse trains as a function of the desired light transmission rate of the control panel.
• FIG. 1 is a partial perspective view of the upper part of a motor vehicle whose roof is equipped with an electrochromic glass panel
• FIG. 3 is a diagram of a power supply management device, according to the invention, of the electrochromic glass roof panel
• FIG. 4 is a diagram similar to FIG. 3 relating to an improved version of the device according to FIG. 'invention.
• Figure 1 partially shows a motor vehicle whose roof comprises a panel 1 of electrochromic glass for a motor vehicle.
• the device for electrically powering the roof panel 1 comprises a computer 2 which is powered by the battery 3 of the vehicle and which is programmed to feed the roof panel 1 by electric pulse trains 4 (see FIG. 2), the amplitude and the period of each pulse train being constant, while the amplitude and / or duration of the pulses in different pulse trains is adjustable depending on the desired light transmission rate.
• the computer 2 is also programmed to maintain the electrical pulse trains 4 for a predetermined maximum duration T1 to prevent the discharge of the battery. These electric pulses 4 are followed by a period T2 during which, only the computer 2 is powered by the battery 3.
• the electrical pulses 4 have an intensity I 5% to obtain for the roof panel 1 a light transmission rate equal to 5%.
• Ip represents the intensity of the current that is consumed by the computer 2 alone, that is to say outside periods T1 during which the pulses 4 are delivered.
• the roof panel 1 becomes dark and the occupants of the vehicle are protected against excessive brightness due to solar radiation.
• the roof panel 1 becomes clear and transparent again.
• the intelligent management of the production of the pulses 4 allows the battery 3 to consume typically 250 ⁇ A over a period of 30 days. Currently, it is planned to disconnect the computer 2 from the power supply provided by the battery after a maximum of eight hours. 007/051055
• the power supply management device of the electrochromic glass roof panel 1 comprises (see FIG. 2) a sensor 5 for detecting the intensity of the ambient brightness and the computer 2 is programmed to disconnect its supplying the battery 3 when the sensor 5 detects that the intensity of the brightness falls below a predetermined threshold.
• the senor 5 is placed in the passenger compartment 6 of the vehicle, behind the windshield, whose transparency is constant.
• This sensor 5 is thus able to detect the drop in brightness occurring at dusk when it is no longer necessary to feed the roof panel 1 to darken it.
• Such a system also allows the device not to operate unnecessarily when the ambient light does not require, especially when the driver forgets to turn off the device overnight.
• the invention thus saves battery power and avoids the risk of discharging it.
• Figure 3 shows the electrical diagram of the power management device of the roof panel 1 of electrochromic glass.
• the battery 3 which electrically feeds the computer 2 which itself feeds the roof panel 1 by trains of electrical pulses to reduce its light transmission rate.
• the light sensor 5 which is able to detect the drop in brightness at dusk and send the computer 2 a corresponding electrical signal which then controls the disconnection of the power supply 2.
• Figure 3 further shows a control button 7 located inside the vehicle, that is to say accessible to the driver, to adjust the amplitude of the electrical pulses 4 according to the transmission rate of desired light from the roof panel 1 of electrochromic glass.
• the control button 7 may have for example the following three positions: position TL 15% (light transmission equal to 15%), in which the roof panel 1 is brightened, position TL 5%, position TL 1%, in which the roof panel is obscured.
• the power supply device of the panel 1 further comprises a sensor 8 of the outside temperature cooperating with the computer 2 to optimize the amplitude of the current pulses 4 which supply the roof panel 1.
• This temperature sensor 8 can be integrated in the roof of the vehicle as shown in FIG.
• This temperature sensor 8 makes it possible, in correlation with the computer 2, to correct the amplitude of the pulses 4 in order to make the opacity of the panel independent of the outside temperature and to optimize a light transmission rate and an electrical consumption of the panel 1 whatever the outside temperature.
• the current pulses are generated by a converter, and vary according to various parameters, including the electrochromic roof temperature and the desired transmission rate.
• the current pulses vary in intensity as a function of the electrochromic roof temperature, so that a low temperature roof will require pulses of higher intensity than a roof at high temperature, or conversely according to the technology of the electrochromic glasses.
• the current pulses vary in duration, for example 100 ms every 1000 ms for a light transmission of 5%, as a function of the required rate of light transmission.
• the diagram of FIG. 4 also shows a CAN 9 (Controller Area Network) diagnostic socket, LIN (Local Interconnect).
• CAN 9 Controller Area Network
• LIN Local Interconnect
• the device that has just been described, given the energy savings it makes it possible to achieve, is particularly useful for managing the power supply of a large-area electrochromic glass roof panel of a vehicle of the minivan type.

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• Physics & Mathematics (AREA)
• Nonlinear Science (AREA)
• General Physics & Mathematics (AREA)
• Optics & Photonics (AREA)
• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Electrochromic Elements, Electrophoresis, Or Variable Reflection Or Absorption Elements (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=37312007

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Family Cites Families (5)

• 2006
  • 2006-04-12 FR FR0603245A patent/FR2899855B1/fr not_active Expired - Fee Related
• 2007
  • 2007-04-03 WO PCT/FR2007/051055 patent/WO2007116174A1/fr active Application Filing
  • 2007-04-03 EP EP07731859A patent/EP2004431A1/de not_active Withdrawn

Non-Patent Citations (1)

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