WO2007060417A1

WO2007060417A1 - Safety system for installation of child safety seats

Info

Publication number: WO2007060417A1
Application number: PCT/GB2006/004355
Authority: WO
Inventors: David Shaun Carine
Original assignee: Britax Childcare Limited
Priority date: 2005-11-22
Filing date: 2006-11-22
Publication date: 2007-05-31

Abstract

The present invention relates to a safety system for fitting of a child safety seat (10) in a motor vehicle. The system comprises a child presence sensing means (21) to sense the presence of a child seated in the child safety seat whilst the first sensing means is activated. A harness tension sensing means (22) is provided in a harness arrangement (14) of the child safety seat to sense a predetermined level of tension in the harness arrangement whilst the harness arrangement sensing means is activated. A driver indicator means (38) is provided to give an indication whenever the child presence sensing means and the harness tension sensing means become deactivated and 'a transmission means is associated with both said sensing means for transmitting a signal to the driver indicator means to show deactivation of either or both said sensing means.

Description

SAFETY SYSTEM FOR INSTALLATION OF CHILD SAFETY SEATS

[001] This invention relates to a safety system for installation of child safety seats in a motor vehicle.

[002] The seatbelts of motor vehicle are not suited to infants, and children below certain sizes and/or ages. In this specification, the general term child will be used for infants and all such children. As a consequence, child safety seats are used in motor vehicles to restrain the child with the intention of reducing the harm to the child in the event of a crash. Child safety seats and the like are secured to the vehicle via various means. The child safety seat itself, in many circumstances, has its own harness to secure the child to the safety seat. Whilst child safety seats are generally forward facing, in the case of a child from birth up to around age three, the child safety seat may be rearward facing.

[003] One of the major problems facing producers of child safety seats is that the user thereof does not properly install the child safety seat in the motor vehicle. For example, problems occur with users not correctly tensioning the seat belt of the motor vehicle or tether that may be used to secure the child safety seat to the vehicle seat. The performance of the child safety seat is significantly reduced if the means of securing the child safety seat to the motor vehicle is loose.

[004] Even when the child safety seat may be properly installed in the motor vehicle, another major problem facing producers of child safety seats concerns the correct use or fitting of any harness of the child safety seat and the adequate tensioning of the harness. If the harness of the child safety seat is loose, then the child can readily exit the safety seat by slipping their arms out of the harness without the knowledge of the driver of the motor vehicle. Even if the harness is only slightly loose, then it will not effectively restrain the child in the event of a crash thereby leading to the increased chance of harm to the child.

[005] Another major problem facing producers of child safety seats is that some older children are able to manipulate the buckle system to the harness of the child safety seat such that it is released and the child can exit the child safety seat. The driver of the motor vehicle may not be aware that this has happened or, if aware, distracted thereby increasing the chance of a crash.

[006] In order to reduce the effect of the potential problems identified above, producers of child safety seats have gone to great lengths to make improvements to and add features to the child safety seat such that installation and fitting and restraining of a child therein is as simple and reliable as possible. Moreover, the producers provide very comprehensive and clear instructions for the installation and fitting/restraint procedure.

[007] Nevertheless, user compliance with the features of the child safety seat and the installation and fitting instructions remains a major problem.

[008] It is an object of the present invention to provide a simple safety system for fitting of child safety seats which can provide security to the user of the child safety seat, which can provide security to the driver of the motor vehicle in which the child safety seat is installed, and which can alert the driver of the motor vehicle in the event that an unsafe situation is occurring in relation to the child in the child safety seat and provide that alert in a manner which does not overtly distract the driver during driving.

[009] According to the present invention there is provided a safety system for fitting of a child safety seat in a motor vehicle, the system comprising :- a child presence sensing means to sense the presence of a child seated in the child safety seat whilst the first sensing means is activated; at least one sensing means provided for sensing at least one of the installation of the child safety seat in the motor vehicle and/or fitting of the child safety seat; driver indicator means for providing an indication whenever the child presence sensing means and the sensing means become deactivated; and transmission means associated with both said sensing means for transmitting a signal to the driver indicator means to show deactivation of either or both 'said sensing means.

[0010] Thus, the present invention enables monitoring of the safe use of a child safety seat and reassures a driver both the safe condition of the child safety seat, as well any changes that may develop in that condition during use. In particular, should the child get off the child safety seat, then the child presence sensing means will become deactivated and in turn will cause the driver indicator means to show a fault.

[0011] In one embodiment, said at least one sensing means comprises a harness tension sensing means provided in a harness arrangement of the child safety seat to sense a predetermined level of tension in the harness arrangement whilst the harness arrangement sensing means is activated.

[0012] Thus, if the harness tension decreases to an unsafe level, then the harness tension sensing means will become deactivated and will in turn cause the driver indicator means to show a fault. The tension in the harness can reduce to an unsafe level either by the buckle being undone, the child partially coming out of the harness, or the harness loosening.

[0013] Conveniently, said ha'rness tension sensing means comprises a two state sensor that is either on or off with the sensor being activated when it is in the on state.

[0014'] In another embodiment, said at least one sensing means comprises a fixing belt tension sensing means provided to sense a predetermined level of tension in a fixing or tether belt for installing the child safety seat in the motor vehicle.

[0015] Thus, the fixing belt tension sensing means can indicate the activated state to the driver indicator means and shows that the child seat is correctly installed before commencing their journey. , Moreover, if the fixing belt tension reduces to an unsafe lever, the fixing belt sensing means will become deactivated and will in turn cause the driver indicator means to show a fault.

[0016] Conveniently, said fixing belt tension sensing means comprises a two state sensor that is either on or off with the sensor being activated when it is in the on state.

[0017] In a preferred embodiment, said child presence sensing means¹ is located in the child safety seat.

[0018] In one case, said child presence sensing means comprises a two state sensor that is either on or off with the sensor being activated when it is in the on state. [0019] In another case, said child presence sensing means comprises a pressure switch located in a seat portion of the child safety seat.

[0020] In an alternative case, said child presence sensing means comprises a combined light beam and photodetector located adjacent a seat portion of the child safety seat.

[0021] Conveniently, the driver indicator means comprises a dashboard mounted device for issuing visual and/or audio signals .

[0022] In one embodiment, the driver indicator means comprises one or more lights that are illuminated green to represent safe fitting of the child safety seat in the motor vehicle .

[0023] In a particular embodiment, the driver indicator means comprises one or more lights that are illuminated red green to represent unsafe fitting of the child safety seat in the motor vehicle.

[0024] 13. A safety system according to any preceding claim wherein the transmission means comprises a wired and/or unwired system for transmitting a signal to the driver indicator means .

[0025] However, the transmission means may include any method for conveying the activation state of the first and second sensors to the driver indicator means. This would include a wire based system employing standard automotive wiring, as well as a wireless system which transmits the activation state to the driver indicator means by a Bluetooth™ or other wireless connection. Alternatively, the activation state could be transmitted to the driver' s mobile phone which in this embodiment would form the driver indicator means receiving an SMS message indicating the activation state of one or more of the sensors.

[0026] Conveniently, the sensing means have switch activator transmitters for transmitting a signal indicating when the sensor is in an activated state.

[0027] In one embodiment the safety system further comprises indicating means provided to provide a visual indication of a child located within the safety seat.

[0028] For example, an indicating means may be provided to other road users by placing an indicator means in one of the windows of the vehicle. Preferably, this is a rear window of the vehicle so that cars traveling behind can be alerted that a child is being carried in the safety seat on the vehicle .

[0029] An example of the present invention will now be described with reference to the accompanying drawings, in which: -

[0030] Figure 1 shows the interior of a motor vehicle having an installed child safety seat of a first embodiment and illustrates a child presence sensing means;

[0031] Figure 2 shows a driver indicator means;

[0032] Figure 3 shows a sign that can be displayed in the window of the motor vehicle;

[0033] Figures 4 to 6 show a harness arrangement sensing means for use with the child safety seat shown in figure 1; and

[0034] Figures 7 to 9 show a vehicle seat belt tension sensing means for use with the child safety seat shown in figure 1.

[0035] Figure 1 shows a safety system embodying the present invention. A child safety, seat 10 is located in a motor vehicle. The" safety seat 10 is secured to the vehicle seat 11 by a vehicle seat belt 12. In this case, it is a lap sash seatbelt which locates through an aperture 13 in the child safety seat 10. The child safety seat 10 has a harness 14 that is used to secure a child within the safety seat. The harness 14 comprises shoulder straps 15 and lap straps 16. A crutch strap 17 is connected to a buckle 18 and there are catches 19 on the shoulder straps 15 that connect to the buckle 18.

[0036] When the harness 14 is secure, a tensioning strap 20 is used to pull the harness tight. A one way clamp (not shown) allows the tensioning strap 20 to be pulled in one direction to tighten the harness 14 but prevents the harness becoming slack by restraining movement of the tensioning strap 20 in the opposite direction without manual operation of a release mechanism.

[0037] With the safety system of the present invention, the child safety seat 10 incorporates a child presence sensing means to sense the presence of a child seated therein. In this embodiment the sensor comprises a weight sensor 21 that has a pressure switch which is activated by the weight of a child sitting in the child safety seat 10. Provided that the child remains in the child safety seat 10, then the weight sensor 21 will remain in an activated or ".on" state.

[0038] In one embodiment of the safety system of the present invention, the child safety seat includes a harness tension sensing means comprising a harness tension sensor 22, which is illustrated in more detail in Figures 4 to 6. The tension sensor 22 comprises a body 24 through which one of the shoulder straps 15 locates. A flap 25 is pivotally connected to the body 24 and a spring 26 acts to force the flap 25 into the open position shown in Figure 5. The portion of the shoulder strap 15 is located through a rail 27 that is secured to the flap 25. Tightening of the harness, and the ■ shoulder strap 15 in particular, causes the flap 25 to rotate to the closed position shown in Figure 4 where the flap 25 is over the body 24.

[0039] In another embodiment of the safety system of the present invention includes a fixing belt tension sensing means provided to sense a predetermined level of tension in a fixing or tether belt for installing the child safety seat in the motor vehicle. This sensing means can be provided instead of or in addition to the harness tension sensing means shown in figures 4 to 6.

[0040] Referring to figures 7 to 9,_. there is shown a seat belt tension sensor 30. This comprises a body 31 with a spring loaded actuator 32 mounted within the body 31. Seat belt guides 33 are attached on either side of the body 31. The seatbelt 12 is threaded between the .seatbelt guides 33 and the actuator 32 as seen in Figures 7 and 8. The spring force on the actuator 32 is sufficient to push the seat belt 12 down between the adjacent guides 33. The position shown in Figure 7 is where there is insufficient tension within the seat belt 12. When the seat belt 12 is correctly tensioned, then the force within the seat belt 12 is sufficient to raise the actuator 32. This provides a visual indication in respect of a post 35 that projects from the top of the body 31. [0041] Both the harness tension sensor 22 and seat belt tension sensor 30 have switching means 28 and 36 that comprise magnetically operated reed switches. These switches 28 and 36 operate to an activated position once the flap 25 closes over the body 24 and the actuator 32 is pushed inwardly within the body 31.

[0042] The operation of one embodiment of the safety system of the present invention will now be described, particularly with reference to figure 2.

[0043] In use, the weight sensor 21 senses the presence of a child in the car safety seat, and in this embodiment, provided the vehicle's ignition is turned on, performs the function of waking or activating the safety system. At this point, the screen of a dashboard mounted driver indicator 38 (driver indicator means) provides a visual indication of the status of the various sensors 21, 22 and 30. Display 38 will be deactivated where the child's weight is no longer sensed by weight sensor 21 or the vehicle's ignition is turne.d off.

[0044] A first portion of the display 39 shows the status of the vehicle seat belt 12 and in particular whether or not there is correct tension as determined by the seat belt tension sensor 30. A second portion 40 shows that the child is present within the child safety seat 10 via the weight sensor 21 and that the harness is correctly tensioned by the harness tension sensor 22.

[0045] In this embodiment, the communication between the dashboard mounted driver indicator 38 and the various sensors 21, 22 and 30 uses wireless transmitters (not shown) with the transmitters built into the sensors or with the sensors connected to a single transmitter, and a receiver built into the driver indicator 38.

[0046] As described previously, when a child is placed in the child safety seat 10, the weight sensor 21 activates the system. Preferably, the respective portions of the driver indicator 38 are illuminated green, provided there is correct tension in the vehicle seat belt 12 and the harness.

Provided that the first and second portions remain green, then the driver knows that the child safety seat is being used safely.

[0047] If the tension in the seat belt 12 or the harness 14 were to go to an unsafe position, then either of the sensors 22 or 30 would become deactivated and a further signal would be sent to the driver indicator 38 whereupon the relevant portion of the display 38 would turn from green to red to alert the driver that the child safety seat is being used unsafely. In addition, an audible signal may be emitted from the driver indicator 38.

[0048] Further, if a child were to climb out of the safety child seat 10 without undoing the harness 14, then this would have the effect of reducing tension in the harness 14 resulting in sensor 22 becoming deactivated causing a signal to be sent to driver indicator 38 resulting in illuminated belt 14 turning from green to red and an associated audible alert. Eventually the weight sensor 21 would also deactivate and ultimately shutdown the system, although such deactivation can have a built in time delay.

[0049] Referring to figure 3 there is shown a sign 41 that can be mounted in the rear window of the vehicle or alternatively on the child safety seat, but still viewable from the rear window of the vehicle. This sign will also illuminate when a child is positioned in the child safety seat. The sign provides an indication to other drivers that a child is present in a child safety seat within the vehicle.

[0050] Preferably, the sign 41 is mounted on an adjustable arm that is in turn attached to the safety seat. The adjustable arm (not drawn) is sufficiently long to enable the sign to be ^• positioned so that it is visible from the rear window of a motor vehicle.

[0051] The sensing means provided for sensing at least one of the installation of the child safety seat in the motor vehicle and/or fitting of the child safety seat may include a tension sensing means which monitors the tension of a top tether strap of a child safety seat where these are used as part of the tethering system to attach the child safety seat to the car and/or for those safety seats incorporating a foot prop contact the monitoring of the extent or presence of loading forces on the foot prop could also be sensed and monitored. Also, where multiple child seats are being employed, the present invention may be adapted to monitor the multiple occupants of these safety seats. Such sensing means can- be provided individually or in combination.

[0052] As can be seen from the above, description, the invention provides an unique combination of sensing and indicator elements which make it possible for a driver to ensure that a child safety seat is correctly installed within a motor vehicle and to also ensure that the child safety seat maintains this safe operating condition throughout a journey.

[0053] It will be apparent that the present invention can take many different forms and configurations, the details of which would be readily apparent to a person skilled in the art. For example, the child presence sensing means can take other forms, for example it can be located in the vehicle seat and is sufficiently sensitive to distinguish a car safety seat with child from an empty vehicle seat and a vehicle seat containing an adult. The child presence sensing means can also use sensors other than a weight sensor, for example a photo diode emitting a light beam and sensor can be used.

Claims

[0054] 1. A safety system for fitting of a child safety seat in a motor vehicle, the system comprising: - a child presence sensing means to sense the presence of a child seated in the child safety seat whilst the first sensing means is activated; at least one sensing means provided for sensing at least one of the installation of the child safety seat in the motor vehicle and/or fitting of the child safety seat; driver indicator means for providing an indication whenever the child presence sensing means and the sensing means become deactivated; and transmission means associated with both said sensing means for transmitting a signal to the driver indicator means to show deactivation of either or both said sensing means.

[0055] 2. A safety system according to claim 1 wherein said at least one sensing means comprises a harness tension sensing means provided in a harness arrangement of the child safety seat to sense a predetermined level of tension in the harness arrangement whilst the harness arrangement sensing means is activated.

[0056] 3. A safety system according to claim 2 wherein said harness tension sensing means comprises a two state sensor that is either on or off with the sensor being activated when it is in the on state.

[0057] 4. A safety system according to any preceding claim wherein said at least one sensing means comprises a fixing belt tension sensing means provided to sense a predetermined level of tension in a fixing or tether belt for installing the child safety seat in the motor vehicle. [0058] 5. A safety system- according to claim 4 wherein said fixing belt tension sensing means comprises a two state sensor that is either on or off with the sensor being activated when it is in the on state.

[0059] 6. A safety system according to any preceding claim wherein said child presence sensing means is located in the child safety seat.

[0060] 7. A safety system according to any preceding claim wherein said child presence sensing means comprises a two state sensor that is either on or off with the sensor being activated when it is in the on state.

[0061] 8. A safety system according to claim 7 wherein said child presence sensing means comprises a pressure switch located in a seat portion of the child safety seat.

[0062] 9. A safety system according to claim 7 wherein said child presence sensing means comprises a combined light beam and photodetector located adjacent a seat portion of the child safety seat.

[0063] 10. A safety system according to any preceding claim wherein the driver indicator means comprises a dashboard mounted device for issuing visual and/or audio signals.

[0064] 11 A safety system according to any one of claims 1 to 9 wherein the driver indicator means comprises one or more lights that are illuminated green to represent safe fitting of the child safety seat in the motor vehicle.

[0065] 12. A safety system according to claim 11 wherein the driver indicator means comprises one or more lights that are illuminated red green to represent unsafe fitting of the child safety seat in the motor vehicle.

[0066] 13. A safety system according to any preceding claim wherein the transmission means comprises a wired and/or unwired system for transmitting a signal to the driver indicator mea'ns .

[0067] 14. A safety system according to any preceding claim wherein the sensing means have switch activator transmitters for transmitting a signal indicating when the sensor is in an activated state.

[0068] 15. A safety system according to any preceding claim further comprising indicating means provided to provide a visual indication of a child located within the safety seat.

[0069] 16. A safety system for fitting of a child safety seat in a motor vehicle, the system substantially as herein described with reference to the accompanying drawings.