Restraint device for a motor vehicle

Abstract

Restraint device for a motor vehicle, comprising a safety belt (5) which can be put on a vehicle occupant (3) located on a vehicle seat (7), and comprising an electronic control unit (23) by means of which at least one restraint means (14, 19, 21) can be controlled, wherein in a occupant restraint mode (R) the control unit (23) can control the restraint means (14, 19, 21) in a critical driving situation (F C ) with a hold-back signal (S R ) in order to exert an optimal restraint effect on the belted vehicle occupant (3), and wherein in a load transport case, instead of the vehicle occupant (3), a load (27) is secured on the vehicle seat (7) by means of the fastened safety belt (5), characterized in that in the load transport case, the electronic control unit (23) can be switched from the occupant restraint mode (R) to a load transport mode (L).

Description

[0001] The invention relates to a restraint device for a motor vehicle according to the preamble of claim 1.

[0002] An exemplary restraint device for a vehicle includes a seat belt that can be fastened to a vehicle occupant seated in a vehicle seat. The restraint device also includes an electronic control unit that can be used to control at least one restraint device that interacts with the seat belt, such as an electric motor-driven reversible belt tensioner and / or a pyrotechnically activated end fitting tensioner of the seat belt. In the event of a crash, these are controlled by the electronic control unit with a restraint signal in order to exert an optimal restraint effect on the belted vehicle occupant.

[0003] Instead of the vehicle occupant, a load can be secured to the vehicle seat using a seat belt. Safe transport of the load is only possible if the vehicle user implements complex securing measures. This is not only uncomfortable, but also leads to insecurity, as securing devices are often not used, allowing the load to shift during transport. Simply using a seat belt is unsuitable, as it only locks at high acceleration and is therefore not suitable for reliable load securing.

[0004] DE 10 2011 121 244 A1 discloses a securing element for securing cargo in a vehicle. The securing element has a first belt connector for connection to a first belt tongue of a first safety belt. Furthermore, the securing element has at least one second belt connector for connection to a second belt tongue of a second safety belt. DE 10 2017 218 976 A1 discloses a safety belt device for a vehicle in which a safety belt, when fastened, secures cargo to a vehicle seat. DE 10 2015 112 191 A1 discloses a system for holding a transport object to an interior wall of a transport vehicle. The transport object is secured to the interior wall of the transport vehicle using a length-adjustable belt.

[0005] A restraint device of this type is known from DE 10 2017 201 965 A1. DE 10 2018 002 967 A1 discloses a method and a device for controlling a reversible belt tensioner, as well as a vehicle. A restraint device for a vehicle is known from DE 10 2017 209 867 A1 and DE 10 2011 122 203 A1. DE 10 2006 053 949 A1 discloses a strain gauge fiber belt.

[0006] The object of the invention is to provide a restraint device for a motor vehicle by means of which a load can be secured on a vehicle seat of a motor vehicle in a reliable and damage-free manner.

[0007] The object is solved by the features of claim 1. Preferred developments of the invention are disclosed in the subclaims.

[0008] The invention is based on a restraint device for a motor vehicle, which has a safety belt that can be fastened to a vehicle occupant sitting on a vehicle seat. The restraint device also has an electronic control unit, by means of which at least one restraint device that interacts with the safety belt can be controlled, such as an electric motor-driven reversible belt tensioner or a pyrotechnically activated end fitting tensioner. In a vehicle occupant restraint mode, the control unit activates the restraint device with a restraint signal in a critical driving situation, such as a crash. This exerts an optimal restraint effect on the belted vehicle occupant. In a cargo transport situation, a load is secured on the vehicle seat using the fastened seat belt instead of the vehicle occupant.

[0009] According to the characterizing part of claim 1, the electronic control unit is switchable between the occupant restraint mode and a cargo transport mode. In cargo transport mode, the control unit controls the restraint device with a cargo transport signal that is different from the restraint signal, ensuring damage-free and reliable cargo securing on the vehicle seat.

[0010] In one technical implementation, the restraint device can be an electric motor-driven reversible seat belt tensioner, controlled by the control unit. In restraint mode and in a critical driving situation, the control unit activates the electric motor-driven reversible seat belt tensioner with a restraint signal, which can be used to limit the restraint force exerted on the vehicle occupant by the fastened seat belt to a predefined force level. To limit the force level, the electric motor-driven reversible seat belt tensioner releases a predefined belt extension path in the event of a crash, causing the vehicle occupant to shift forward in order to reduce the restraint force acting on them.

[0011] In contrast to the vehicle occupant restraint mode, the cargo transport mode is described below: In cargo transport mode, the control unit activates the electric motor-driven reversible belt tensioner with a transport signal, which the belt tensioner uses to tighten the seat belt with a predefined holding force. This predefined holding force secures the cargo tightly to the vehicle seat. Once the predefined holding force is reached, the belt webbing is locked, preventing any belt webbing extension (even in critical driving situations, such as a crash). The cargo is thus always tightly secured to the vehicle seat, regardless of the driving situation.

[0012] In a specific embodiment, the electronic control unit can have an input device, such as a switch, an app, or a sensor, with which the cargo transport mode can be activated or deactivated. For example, the cargo transport mode can be activated or deactivated by opening or closing a seat belt buckle.

[0013] When the load transport mode is deactivated, for example at the end of the journey, the electric motor-driven reversible belt tensioner can release the belt strap and release the holding force so that the load can be removed from the vehicle without creating any interference.

[0014] In a preferred embodiment, the safety belt is a three-point safety belt consisting of a lap belt portion and a shoulder belt portion. When fastened, the lap belt portion of the safety belt runs in the transverse direction of the vehicle between floor-side attachment points, one of which is implemented as a belt buckle-tongue connection. The lap belt portion merges into the shoulder belt portion at a belt tongue eyelet. This is routed from the belt tongue eyelet diagonally across the vehicle occupant's chest to an upper attachment point implemented as a deflection fitting. At the deflection fitting, the shoulder belt portion is deflected toward the electromotively reversible belt pretensioner. In addition, a pyrotechnically activated end fitting pretensioner can be assigned to the lap belt portion at its attachment point. The pyrotechnically activated end fitting pretensioner is also a restraint device that can be controlled by the control unit.This is activated in the event of a crash to remove any slack from the lap belt section and thus reduce forward displacement of the pelvis.

[0015] If the cargo transport mode is activated and a critical driving situation, such as a crash, occurs, the following occurs: The electronic control unit leaves the pyrotechnically activated end fitting tensioner deactivated. This prevents damage to the cargo strapped to the vehicle seat. Furthermore, by not triggering the end fitting tensioner, a repair measure is avoided that would otherwise be required if the end fitting tensioner were triggered pyrotechnically.

[0016] Alternatively or additionally, the restraint device may include at least one occupant airbag as a restraint device. When the vehicle occupant restraint mode is activated and in the event of a critical driving situation, such as a crash, the control unit activates the occupant airbag with a restraint signal to protect the vehicle occupant.

[0017] In contrast, when cargo transport mode is activated and a critical driving situation, such as a crash, occurs, the following occurs: The control unit leaves the occupant airbag deactivated. This prevents damage to the cargo strapped to the vehicle seat due to the deploying occupant airbag. Furthermore, the non-deployment of the occupant airbag avoids the need for repairs that would otherwise be required if the occupant airbag were deployed.

[0018] In a further embodiment, the control unit can be connected to an optical sensor, such as a camera or radar system, which can be used to detect seat occupancy. When the cargo transport mode is activated, the control unit can use the optical sensor to detect relative movement of the cargo with respect to the vehicle seat. Upon detection of such relative movement, the control unit can activate the electric motor-driven reversible belt tensioner to increase the predefined load-holding force of the seat belt.

[0019] For convenient operation, the control unit can also be connected to a display. The display indicates whether the cargo transport mode or the vehicle occupant restraint mode is activated for the respective vehicle seat. This can be done, for example, by a mechanical display, a light source, and / or a text overlay in the HMI.

[0020] An embodiment of the invention is described below with reference to the accompanying figures. They show: Fig. 1 to 3 are schematic views illustrating the restraining device according to the invention.

[0021] In the Fig. 1 shows a schematic diagram of a vehicle interior 1 with a vehicle occupant 3 located on the passenger side. The occupant is secured to a vehicle seat 7 by a three-point safety belt 5. The three-point safety belt 5 consists in a known manner of a lap belt portion 9 and a shoulder belt portion 11. As can be seen from the Fig. 2, the lap belt portion 9 of the safety belt 5 runs between floor-side attachment points 13, 14 in the vehicle transverse direction y. Of the two attachment points 13, 14, Fig. 1 only the connection point 14 is shown, which is realized by means of a pyrotechnically activated end fitting tensioner. The connection point 13 opposite in the vehicle transverse direction y ( Fig. 2) is implemented as a conventional belt buckle-belt tongue connection with a belt tongue 27 and a belt buckle 28. At a belt tongue eyelet, the lap belt portion 9 merges into the shoulder belt portion 11. The shoulder belt portion 11 is in the Fig. 2, starting from the belt tongue 27, is guided diagonally across the chest area of the vehicle occupant 3 to an upper deflection fitting 15 at the upper edge of the backrest 17 of the vehicle seat 7. Via the deflection fitting 15, the shoulder belt portion 5 is deflected in the direction of an electromotively reversible belt tensioner 19, which is integrated in the backrest 17.

[0022] In addition, an occupant airbag 21 is provided in the head impact area of the instrument panel 20. The occupant airbag 21, the electromotive reversible belt tensioner 19 and the pyrotechnically activated end fitting tensioner 14 are integrated in the Fig. 1 and Fig. 2 in signal connection with an electronic control unit 23. This is assigned a crash sensor system 25. In the event of a critical driving situation, for example in the event of a crash with a crash force F acting on the front of the vehicle C , the passenger airbag 21, the electromotive reversible belt tensioner 19 and / or the end fitting tensioner 14 are supplied by the control unit 23 with a restraint signal S RBy activating the electromotive reversible belt tensioner 19, a belt extension path s is released if necessary. In this way, a forward displacement V of the vehicle occupant 3 occurs towards the front of the vehicle. By providing the belt extension path s, the restraining force F exerted by the safety belt 5 on the vehicle occupant 3 can be R be limited to a predefined force level.

[0023] Alternatively and / or additionally, the control unit 23 can actuate the pyrotechnically activated end fitting tensioner 14 in the event of a crash. This removes slack from the lap belt portion 9 in the event of a crash, thus reducing forward pelvic displacement.

[0024] A core of the invention is that the electronic control unit 23 can switch between an occupant restraint mode R ( Fig. 1) and a cargo transport mode L ( Fig. 3) is switchable. In the Fig. 1, the occupant restraint mode R is activated, so that in the event of a crash, the electronic control unit 23 supplies the occupant airbag 21, the electromotive reversible belt tensioner 19 and / or the end fitting tensioner 14 with restraint signals S R in order to exert an optimal restraint effect on the belted vehicle occupant 3.

[0025] In contrast, in the Fig. 3 indicates a load transport case in which, instead of the vehicle occupant 3, a load 27 is secured on the vehicle seat 7 by means of the seat belt 5. When the load transport mode L is activated, the electronic control unit 23 controls the occupant airbag 21, the electromotive reversible belt tensioner 19 and / or the end fitting tensioner 14 with a signal from the restraint signal S R different cargo transport signal S TIn this way, damage-free and reliable securing of the load on the vehicle seat 7 is ensured in various driving situations, especially in the event of a crash.

[0026] In load transport mode L according to the Fig. 3, the electromotive reversible belt tensioner 19 is actuated with a transport signal S T controlled, with which the belt tensioner 19 tensions the safety belt 5 with a predefined holding force F H by means of which the load 27 is tightly tied to the vehicle seat 7. When the predefined holding force F H A belt strap lock takes place so that, for example, in the event of a crash, the belt strap cannot be pulled out.

[0027] When the load transport mode L is activated, the control unit 23 leaves the end fitting tensioner 14 and the occupant airbag 21 deactivated in order to avoid damage to the load 27 strapped to the vehicle seat 7.

[0028] In the Fig. 1 and Fig. 2, the electronic control unit 23 is assigned a crash sensor system 25, by means of which a critical driving situation leading to a crash can be detected. Furthermore, the electronic control unit 23 is assigned an input unit 29, by means of which a vehicle user can switch between the load transport mode L and the occupant restraint mode R. Alternatively and / or additionally, the load transport mode L can be activated / deactivated, for example, by closing or opening the belt buckle. When the load transport mode L is deactivated, for example at the end of a journey, the belt webbing is released in the electromotively reversible belt tensioner 19, and the holding force F H released so that the load 27 is unlocked and can be removed from the vehicle.

[0029] As can be seen from the Fig. 1 and Fig.As further shown in Figure 2, the electronic control unit 23 is in signal communication with an optical sensor system 31, such as a camera or a radar system, by means of which seat occupancy detection can be carried out. When the load transport mode L is activated, a relative movement of the load 27 with respect to the vehicle seat 7 can be detected with the aid of the optical sensor system 31. Upon detection of such a relative movement, the control unit 23 can actuate the electromotively reversible belt tensioner 19 in order to maintain the predefined holding force F H to increase. In addition, the control unit 23 is assigned a display means 33 with which the load transport mode L or the occupant restraint mode R can be displayed. List of reference symbols 1 vehicle interior 3 vehicle occupants 5 Seat belt 7 Vehicle seat 9 Lap belt portion 11 Shoulder strap portion 13 lower pivot point 14 pyrotechnically activated end fitting tensioners 15 upper deflection fitting 17 Backrest 19 electromotive reversible belt tensioner 20 Instrument panel 21 Passenger airbag 23 electronic control unit 25 Crash sensors 27 Cargo 29 Input devices 31 optical sensors 33 Display devices L Cargo transport mode R Occupant restraint mode S R Retention signal S T Transport signal s belt extension F H Holding force F C Crash force F R Retaining force V Occupant forward displacement

Claims

[1] Restraint device for a motor vehicle, comprising a safety belt (5) which can be put on a vehicle occupant (3) located on a vehicle seat (7), and comprising an electronic control unit (23) by means of which at least one restraint means (14, 19, 21) can be controlled, wherein in a occupant restraint mode (R) the control unit (23) can control the restraint means (14, 19, 21) in a critical driving situation (F C ) with a hold-back signal (S R ) in order to exert an optimal restraint effect on the belted vehicle occupant (3), and wherein in a load transport case, instead of the vehicle occupant (3), a load (27) is secured on the vehicle seat (7) by means of the fastened safety belt (5), characterized by that in the case of cargo transport, the electronic control unit (23) can be switched from the occupant restraint mode (R) to a cargo transport mode (L). [2] Restraint device according to claim 1, characterized bythat the restraint means is an electromotively reversible belt tensioner (19) of the safety belt (5) which can be controlled by the control unit (23). [3] Restraint device according to claim 2, characterized by that in the load transport mode (L) the control unit (23) supplies the electromotive reversible belt tensioner (19) with a transport signal (S T ) with which the belt tensioner (19) holds the seat belt (5) with a predefined holding force (F H ), by means of which the load (27) is tightly tied to the vehicle seat (7). [4] Restraint device according to one of the preceding claims, characterized by that the electronic control unit (23) is assigned an input means (29) by means of which the load transport mode (L) can be activated or deactivated, and / or that when the load transport mode (L) is deactivated, the belt tensioner (19) releases the belt strap and the holding force (F H ) solves. [5] Restraint device according to one of the preceding claims, characterized by that the safety belt (5) is a three-point safety belt, the shoulder belt portion (11) of which is assigned a belt tensioner (19) and the lap belt portion (9) of which is assigned a pyrotechnically activatable end fitting tensioner (13) which, in the event of a crash (F C ) pulls a slack belt out of the lap belt section (9) and thus reduces forward displacement of the pelvis. [6] Restraint device according to claim 5, characterized by that in load transport mode (L) and in the event of a crash (F C ) the control unit (23) leaves the end fitting tensioner (13) deactivated in order to avoid damage to the load (27) strapped to the vehicle seat (7) or to avoid a repair measure required to restore the end fitting tensioner function after the end fitting tensioner (13) has been triggered. [7] Restraint device according to one of the preceding claims, characterized bythat the restraint device has at least one occupant airbag (21) as a restraint means, which in the restraint mode (R) and in the event of a crash (F C ) from the control unit (23) with a retention signal (S R ) can be activated to protect the vehicle occupant (3). [8] Restraint device according to claim 7, characterized by that in load transport mode (L) and in the event of a crash (F C ) the control unit (23) leaves the occupant airbag (21) deactivated in order to avoid damage to the load (27) strapped onto the vehicle seat (7) or to avoid a repair measure required to restore the airbag function after the occupant airbag (21) has been triggered. [9] Restraint device according to one of the preceding claims, characterized by that the control unit (23) is in signal connection with an optical sensor system (31) by means of which seat occupancy detection can be carried out. [10] Restraint device according to one of the preceding claims, characterized by that the control unit (23) is assigned a display means (33) which displays the load transport mode (L) or the occupant restraint mode (R).

Images