Safety arrangement for a seat in a motor vehicle

Abstract

A safety arrangement for a seat in a motor vehicle is described. This safety arrangement comprises a seatbelt system, a monitoring system, and use indicating means for the seatbelt system, wherein the seatbelt system comprises a belt webbing, a tongue being slidingly arranged on the belt webbing, and a buckle for inserting an insertable part of the tongue, such that in the buckled state, the belt webbing comprises a shoulder section (12) and a lap section (14). The monitoring system monitors the position of the shoulder section (12) and the position of the lap section (14) relative to the belted person and comprises a control unit and a camera. In order to ensure that the person sitting in the seat is not only belted but also correctly belted, the control unit controls the use indicating means based on data provided by the camera and the use indicating means indicate the correct or incorrect position of the shoulder section (12) and the correct or incorrect position of the lap section (14).

Description

[0001] Safety arrangement for a seat in a motor vehicle

[0002] The invention relates to safety arrangement for a seat in a motor vehicle according to claim 1 .

[0003] A safety belt system is a part of the seat system of nearly every passenger seat in a passenger car. Such a seatbelt system comprises a belt webbing, a tongue being slidingly arranged on the belt webbing and a buckle for inserting an insertable part of this tongue. In most cases the seatbelt system is a so-called three-point seatbelt system meaning that when the tongue is inserted into a buckle, the tongue divides the belt webbing into the shoulder section and a lap section.

[0004] Many seatbelt systems comprise a monitoring system which monitors the use state of the seatbelt system when the vehicle seat is occupied and use indicating means which indicate at least the non-use of the seatbelt system if such a non-use is detected. This seatbelt system usually comprises a control unit. A very common way to monitor this buckling state is the use of a buckle sensor which detects the presence of the insertable part of the tongue in the buckle.

[0005] When the control unit (this can be a separate control unit or a part of the general vehicle control unit / ECU) monitors that a seat is occupied, but the insertable part of the tongue is not inserted into the buckle, an alert (most often a tone signal) is triggered by the control unit. This alert forms the use indicating means in this case. If no additional measures are taken, such a system can easily be cheated, for example by inserting an “extra tongue” (which is not connected to the belt webbing) into the buckle. More sophisticated monitoring systems are known which do not allow a cheating by the occupant; an example for such an advanced system is described in US 2022 / 0250570 A1 .

[0006] For example from generic US 2019 / 0152430 A1 a monitoring system is known which does not only monitor if or if not the seatbelt system is used, but also if the shoulder section and the lap section of the belt webbing are positioned in a correct way. This monitoring system comprises sensible elements disposed in the webbing and sensors that are disposed in the occupant seat. It is proposed in this document that the control unit does not allow a movement of the vehicle - which can especially be an autonomous vehicle - if the belt webbing is not properly worn by the occupant.

[0007] Starting from this prior art it is the task of the invention to provide a safety arrangement for a seat in a motor vehicle comprising a monitoring system for the belt webbing and use indicating means which are easy to implement in the vehicle and which improve the acceptance of the users.

[0008] This task is solved by a safety arrangement having the features of claim 1 .

[0009] According to the first aspect, the monitoring system comprises a camera which “looks” at the belted person. The signals of this camera are transferred to the control unit and this control unit judges the correct or incorrect position of the lap section and shoulder section based on the signals provided by the camera, for example by comparing the pictures captured by the camera with stored patterns showing typical examples for the correct position and typical examples for the incorrect position of those sections of the belt webbing.

[0010] In this context it is often sufficient for the control unit to look for the height of the lap section relative to the lap of the belted person and to check if the shoulder section extends substantially over the middle of the shoulder between the shoulder’s outer end (from where the arm extends) and the neck of the person to be protected. Those positions can easily be recognized by comparing the captured pictures with stored examples or patterns and / or by using artificial intelligence. The task is relatively easy, because the belt webbing, especially its shoulder section and its lap section have very clear and easily to detect shapes and also, the torso of a human has a rather simple shape.

[0011] According to a second aspect of the invention, the use indicating means do not only inform the user whether or not the belt system is used, but also whether or not the webbing is positioned in a correct way. This is based on the following findings: Although it is often the case that the belt webbing is incorrectly positioned from the very beginning, it is also possible that the webbing position relative to the person changes during the journey, for example in such a way that the belt webbing is initially positioned in a correct way, but is positioned incorrectly at a later stage, for example because the belted person changes its position. In this case it is usually no option that the control unit brings the vehicle to a forced stop. Instead, the use indicating means provide information about the correct or incorrect position of the shoulder section and information about the correct or incorrect position of the lap section. If the user is informed about an incorrect position of either one of those sections, he is “invited” to correct this, which can usually be done by the user himself / herself while the motor vehicle keeps on driving.

[0012] It is of course preferred that the monitoring and indicating starts as soon as the seat is occupied or latest after the person is buckled, and continues from there on until the end of the journey (for example until the ignition of the motor is turned off).

[0013] In a preferred embodiment, the use indicating means comprise at least one first light emitting area having a first state indicating the correct position of the shoulder section and a second state indicating the incorrect position of the shoulder section, and at least one second light emitting area having a first state indicating the correct position of the lap section and a second state indicating the incorrect position of the lap section. As has been described above, it is a general concept of the invention to instruct the belted person in such a way that the person itself corrects the position of the belt if necessary. It turned out that it is very helpful for the person to know which of the belt sections is positioned correctly and which not (often, one section is positioned in the right way, while the over section is positioned falsely).

[0014] It is of course desired that the whole safety arrangement can be used by everyone in an intuitive way. To achieve this, it can be preferred that the at least one first light emitting area and the at least one second light emitting area are areas of a symbolic representation the belt webbing in its buckled state in such a way that the first light emitting area represents the shoulder section at least indirectly and the second light emitting area represents the lap section at least indirectly. By this, he user can directly understand what the indicating means “want to tell him / her” without reading a manual. This symbolic representation can for example be generated on a display which is often provided anyway, such that the additional efforts necessary are low. This display can be for example integrated or attached to the instrument panel or the steering wheel. Alternatively or additionally, the at least one first light emitting area and the at least one second light emitting area can be disposed on the belt webbing itself, preferably on its shoulder section. In this case, the “belt webbing position information” is directly linked with the belt webbing itself which turned out to be intuitive to a high degree.

[0015] Of course, the states of the light emitting areas must be distinguishable for the user and in a preferred embodiment this is achieved by different colors such that the first light emitting area emits light in a first color when in its first state and light in a different second color when in its second state. In the same way, the second light emitting area emits light in a third color when in its first state and light in a different fourth color when in its second state. Commonly, the first and the third color are green and the second and the fourth color are red, because this is usually directly understood by the user and also motivating since most persons want to change the color from red to green. In an alternative, the light emitting areas are off (they do not emit light) in their first state and emit light (preferably a light in a red color) when in their second state.

[0016] As a further alternative, or further additionally, the use indicating means can comprise a voice generator or a tone generator. One advantage of using a voice generator can be that the belted person can directly be told what he / she needs to do in order to correct the belt webbing position. A drawback can be that the usage of a voice generator can be annoying, especially if a plurality of persons is sitting in the car. As a compromise, the voice- or tone generator is only activated by the control unit when the belted person does not react when an incorrect use of the belt webbing is indicated by other use indicating means.

[0017] As a further alternative or additionally, the use indicating means can comprise a first vibrating element in the shoulder section and a second vibrating element in the lap section such that a not correct position can be indicated by a vibration signal.

[0018] The monitoring system can additionally comprise at least one of a buckle sensor and a belt-extraction-sensor such that in a first step, the systems has a “buckled / unbuckled information”; checking the belt webbing in view of a correct or not correct position of its sections is of course not sensible in an unbuckled state.

[0019] The invention will now be described by means of a preferred embodiment in view of the figures. The figures show:

[0020] Figure 1 a schematic side view onto a belted passenger and a schematic representation of some parts of the monitoring system and of the use indicating system,

[0021] Figure 2 the belted passenger in a view from direction R1 in Figure 1 ,

[0022] Figure 3 a view onto the display-camera-unit of Figure 1 in a view from direction R2 in Figure 1 ,

[0023] Figure 4 an enlarged representation of the symbolic representation displayed in the display of the display-camera-unit of Figure 3,

[0024] Figure 4a a variation to the symbolic representation shown in Figure 4, Figure 5 a belted driver with an incorrectly positioned lap section of the belt webbing,

[0025] Figure 6 the symbolic representation of the use indicating system seen by the driver,

[0026] Figure 7 what is shown in Figure 5 with the driver correcting the position of the lap section,

[0027] Figure 8 what is shown in Figure 7 after the correction of the lap section has been completed,

[0028] Figure 9 the symbolic representation of Figure 6 after the correction of the lap section has been competed, and

[0029] Figure 10 a flowchart showing the working principle of the control unit.

[0030] Figures 1 to 3 show schematically a passenger sitting on a passenger seat and being belted by the belt webbing of a seat belt system. Further, all elements of a monitoring system and a use indicating system of the described embodiment of the invention are shown. The seatbelt system is a common three-point seatbelt system and comprises a belt webbing 10, a tongue 16 arranged on the belt webbing 10 and a buckle 18. The belt webbing 10 extends from a retractor 11 to an end fitting 19 and in the buckled state; the belt webbing 10 comprises a shoulder section 12 and a lap section 14. As can be seen, a first belt-mounted light emitting element 31 and a second belt-mounted light emitting element 32 are provided on the shoulder section 12 of the belt webbing 10. Those beltmounted light emitting elements 31 and 32 are both essentially of rectangular shape and the longer axis of the first belt-mounted light emitting element 31 extends essentially into the direction of the belt webbing and the longer axis of the second belt-mounted light emitting element extends essentially perpendicular to the same. The first belt-mounted light emitting element 31 provides a first light emitting area 31 a on the belt webbing 10 and the second belt-mounted light emitting element 32 provides a second light emitting area 32a on the belt webbing. The light emitting elements 31 and 32 are preferably embodied in form of LEDs or OLEDs and are designed such that they can emit light in at least two colors, preferably red and green. Such color changing LEDs or OLEDs are well known in the prior art.

[0031] In front of the passenger, a display-camera-unit 40 is provided and in the embodiment shown this display-camera-unit 40 extends from the instrument panel 60. It is not necessary for the invention that the camera 44 is integrated in the display-camera-unit 40, it could also be a separate unit and further it should be noted that the camera can be shared with other systems, especially other safety systems. But, for the sake of simplicity, a display-camera-unit 40 is shown and despite the simplicity of representation, it is to be mentioned that integrating the camera 44 into such a display-camera-unit 40 gives the camera a very good position for its task. The display 42 of the display-camera-unit 40 can of course be seen by the passenger. The lens 43 of the camera can be seen in Figure 3.

[0032] The display-camera-unit 40 and the belt-mounted light emitting elements 31 , 32 are connected to a control unit 20, as is schematically shown in Figure 1 . This control unit 20 receives data from the camera 44 and controls the display 42 as well as the belt-mounted light emitting elements 31 , 32. As has already been mentioned, the control unit 20 does not need to be a control unit 20 which is only responsible for the task described here; it can also be a more general control unit.

[0033] As is indicated in Figure 3, the control unit 20 can control the display 42 in such a way that it displays a symbolic representation 50 of a belted person wherein also here, a first light emitting area 51 a a second light emitting area 52a are provided. In the embodiment shown, those first and second light emitting areas 51 a and 52a are located on the representation of the belt webbing in the same way as the belt-mounted light emitting elements 31 and 32 are located on the physical belt webbing 10. As an alternative, the second light emitting area 52a could be located on the representation of the lap section of the belt webbing, as is shown in Figure 4a. It is possible to use the display additionally for other information, for example entertainment information as it is indicated in Figure 3.

[0034] It needs to be mentioned that it is often preferred to provide both: Belt-mounted light emitting elements 30, 31 and a symbolic representation 50 having light emitting areas 51 a, 52a, but it would also be possible to provide only one of those. But providing both enhances the chances that the user recognizes an indication of a not correct use of the belt webbing 10 without the (also possible) use of a tone signal or artificial voice which could be annoying for the other persons in the motor vehicle.

[0035] The working principle is now described in view of Figure 10 showing a flowchart. After the system has been started (for example when the ignition has been turned on) and a seat is detected as being occupied (form example by using a seat occupancy sensor - not shown in the Figures), it is first checked if the assigned seatbelt system is worn. This can be done by the control unit 20 exclusively by using the camera signals and / or by additionally using a signal from a buckle sensor (not shown) or signals from a sensor provided in the retractor 1 1 (also not shown). If it is detected that a person is not buckled, a warning signal is triggered, for example a tone signal. This is repeated until a buckled state is detected, as is common in passenger cars.

[0036] When a buckled state is detected, the control unit 20 checks the position of the shoulder section 12 and the position of the lap section 4 of the belt webbing 10 based on the signals provided by the camera 20, for example by comparing the captured pictures with stored patterns. If it is judged that the shoulder section 12 is in its correct position, the first light emitting areas (on the belt and in the symbolic representation in the display) are controlled to emit light in a green color. If it is judged by the control unit 20 that the shoulder section 12 is not in a correct position, the first light emitting areas (belt and display) are controlled to emit light in a red color. If it is judged that the lap section 14 is in its correct position, the second light emitting areas (on the belt and in the symbolic representation in the display) are controlled to emit light in a green color. If it is judged by the con- trol unit 20 that the lap section 14 is not in a correct position, the second light emitting areas (belt and display) are controlled to emit light in a red color. This is repeated until the system is deactivated, for example because the ignition has been turned off. In an alternative, the light emitting areas are off (they do not emit light) in their first state.

[0037] In view of Figures 5 to 9 it is now described how the safety arrangement helps the user (here the driver) to find the correct position of the belt webbing 10. This is described - as an example - with an initial incorrect position of the lap section 14, but the same principle applies (although not shown) if the shoulder section is not correctly positioned.

[0038] One can see in Figure 5 that the lap section 14 is not correctly positioned; it is positioned too high and extends over the belly not over the lap of the diver. This is detected by the monitoring system and the control unit 20 controls the second belt mounted light emitting element 32 to emit light in a red color. The same applies to the second light emitting area 52a of a symbolic representation if present (please see Figure 6). In the symbolic representation, an arrow can additionally indicate in which direction the respective section of the belt webbing needs to be re-positioned.

[0039] When the user recognizes this, he can re-position the respective belt section (here the lap section 14) until it reaches its correct position (Figure 8). As soon as this is recognizes by the monitoring system, the control unit controls the second belt mounted light emitting element 32 in such a way that it emits light in a green color. The same applies of course to the second light emitting area 52a of the symbolic representation 50.

[0040] One can see that the safety of the person to be protected can be enhanced by relatively simple means and without drastic measures like stopping the car. List of reference numbers

[0041] 10 belt webbing

[0042] 11 retractor

[0043] 12 shoulder section

[0044] 14 lap section

[0045] 16 tongue

[0046] 18 buckle

[0047] 19 end fitting

[0048] 20 control unit

[0049] 31 first belt-mounted light emitting element

[0050] 31 a light emitting area of first belt-mounted light emitting element (first light emitting area)

[0051] 32 second belt-mounted light emitting element

[0052] 32a light emitting area of second belt-mounted light emitting element (second light emitting area)

[0053] 40 display-camera-unit

[0054] 42 display

[0055] 44 camera

[0056] 43 lens of camera

[0057] 50 symbolic representation

[0058] 51 a first light emitting area of symbolic representation

[0059] 52a second light emitting area of symbolic representation

Claims

Claims1 . A safety arrangement for a seat in a motor vehicle, comprising a seatbelt system, a monitoring system, and use indicating means for the seatbelt system, wherein the seatbelt system comprises a belt webbing (10), a tongue (16) being slidingly arranged on the belt webbing (10), and a buckle (18) for inserting an insertable part of the tongue (16), such that in the buckled state, the belt webbing (10) comprises a shoulder section (12) and a lap section (14), the monitoring system monitors the position of the shoulder section (12) and the position of the lap section (14) relative to the belted person, and the monitoring system comprises a control unit (20), characterized in that the monitoring system comprises a camera (44), the control unit (20) controls the use indicating means based on data provided by the camera (44), and the use indicating means indicate the correct or incorrect position of the shoulder section (12) and the correct or incorrect position of the lap section (14).

2. The safety arrangement of claim 1 , wherein the use indicating means comprise at least one first light emitting area having a first state indicating the correct position of the shoulder section (12) and a second state indicating the incorrect position of the shoulder section (12), and at least one second light emitting area having a first state indicating the correct position of the lap section (14) and a second state indicating the incorrect position of the lap section (14).

3. The safety arrangement of claim 2, wherein the at least one first light emitting area and the at least one second light emitting area are areas (51 , 52) of a symbolic representation (50) of the belt webbing in its buckled state, wherein the first light emitting area (51 ) represents the shouldersection (12) at least indirectly and the second light emitting area (52) represents the lap section at least indirectly.

4. The safety arrangement of claim 3, wherein the symbolic representation (50) is generated on a display (42).

5. The safety arrangement of any one of claims 2 to 4, characterized in that the at least one first light emitting area (31 a) and the at least one second light emitting area (32a) are disposed on the belt webbing (10), preferably on its shoulder section (12).

6. The safety arrangement of any one of claims 2 to 5, wherein the first light emitting area (31 a, 51 ) emits light in a first color when in its first state and light in a second color when in its second state, said second color being different from said first color, and the second light emitting area (32a, 52) emits light in a third color when in its first state and light in a fourth color when in its second state, said fourth color being different from said third color, wherein it is preferred the third color is identical to the first color and the fourth color is identical to the second color, and wherein it is further preferred that the first color and the third color are green and that the second color and the fourth color are red7. The safety arrangement of any one of claims 2 to 5, wherein the first light emitting area (31 a, 51 ) emits no light when in its first state and emits light when in its second stat, and the second light emitting area (32a, 52) emits light when in its first state and emits no light when in its second state, wherein it is preferred that the light emitting areas (31 a, 32a, 51 , 52) emit light in a red color in their second state.

8. The safety arrangement according to any one of the preceding claims, wherein the use indicating means comprise a voice generator.

9. The safety arrangement of any one of the preceding claims, characterized in that the use indicating means comprise a vibrating element in the shoulder section (12) and / or a vibrating element in the lap section (14).

10. The safety arrangement of any one of the preceding claims, characterized in that the monitoring system additionally comprises at least one of a buckle sensor and a belt-extraction-sensor.

Images