JP2021046018A - Seatbelt control apparatus - Google Patents

Abstract

To realize a seatbelt control apparatus capable of lowering discomfort for an occupant caused by the tension of the seatbelt while exerting the function of protecting the occupant.SOLUTION: A tension reducer 42, being operated by a solenoid 48, reduces winding force of winding up a seatbelt 22 onto a spool 32 by reducing torque applied to the spool 32 by an energizing mechanism 34. In a case where a determination part 52 determines that there is no non-automatic driving vehicle in the surrounding area of a vehicle itself, a control part 54 controls the solenoid 48 so as to reduce winding force of winding up the seatbelt 22 onto the spool 32 in comparison with the case of the determination part 52 determining that there is a non-automatic driving vehicle in the surrounding area of the vehicle itself.SELECTED DRAWING: Figure 1

Description

The present invention relates to a seatbelt control device.

The following Patent Document 1 discloses a technique relating to a control device for an occupant protection device. In this prior technology, when another vehicle approaching the own vehicle is identified as being manually driven, the control unit can protect the occupant by operating at least one of the pretensioner and the airbag of the own vehicle. The seatbelt module is controlled to operate so that the seatbelt is involved until the amount is reached. On the other hand, in the above-mentioned prior art, when another vehicle approaching the own vehicle is identified as being in automatic driving, the control unit does not operate the seat module. As a result, the above-mentioned prior art attempts to exert the occupant protection function while suppressing the occupant's comfort from being impaired.

JP-A-2017-206200

By the way, in the above-mentioned Patent Document 1, there is no specific description about how to wind a seatbelt, but there is a description that the amount of winding up of a seatbelt is controlled. It is presumed that a configuration in which the seat belt is wound by a motor is adopted.

However, if the configuration in which the seatbelt is wound by the motor is adopted in the above-mentioned prior art, the occupant may feel the tension of the seatbelt every time the motor is driven, which may give the occupant a sense of discomfort.

In consideration of the above facts, an object of the present invention is to obtain a seatbelt control device capable of reducing the discomfort of the occupant due to the tension of the seatbelt while exerting the occupant protection function.

The seatbelt control device of the present invention according to claim 1 has an urging mechanism provided with two types of springs, strong and weak, for changing the winding force for winding the seatbelt around the winding shaft, and is operated by a solenoid. In a seatbelt control device that controls the winding force by providing an electric tension reducer that reduces the torque acting on the winding shaft from the urging mechanism to reduce the winding force. When the determination unit determines whether or not there is a non-autonomous driving vehicle around the vehicle and the determination unit determines that there is no non-autonomous driving vehicle around the own vehicle, the determination unit is around the own vehicle. It has a control unit that controls the solenoid so that the winding force is reduced as compared with the case where it is determined that a non-autonomous driving vehicle exists.

According to the above configuration, the electric tension reducer has an urging mechanism equipped with two types of springs, strong and weak, for changing the winding force for winding the seat belt around the winding shaft, and is operated by a solenoid. By doing so, the torque acting on the take-up shaft from the urging mechanism is reduced to reduce the take-up force. Then, when the determination unit determines that the non-autonomous driving vehicle does not exist around the own vehicle, the winding force is higher than that when the determination unit determines that the non-autonomous driving vehicle exists around the own vehicle. The control unit controls the solenoid so that Here, since the winding force is continuously (gradually) reduced by the spring, the discomfort of the occupant due to the tension of the seat belt is reduced.

As described above, the seatbelt control device of the present invention has an excellent effect of being able to reduce the discomfort of the occupant due to the tension of the seatbelt while exerting the occupant protection function.

It is a side view which shows typically the vehicle seatbelt device and the vehicle seat provided with the seatbelt control device which concerns on one Embodiment of this invention. It is a flowchart which shows the flow of the control process by the ECU of a seatbelt control device.

A seatbelt control device according to an embodiment of the present invention will be described with reference to FIG. In these figures, the arrow FR appropriately shown indicates the front side of the vehicle, and the arrow UP indicates the upper side of the vehicle.

FIG. 1 shows a schematic side view of a vehicle seatbelt device 20 (hereinafter, simply referred to as “seatbelt device 20”) and a vehicle seat 10 including the seatbelt control device 40 according to the present embodiment. ing. The vehicle seat 10 shown in FIG. 1 is, for example, a front seat for the driver's seat. In the present embodiment, a dummy P is seated on the vehicle seat 10 instead of the actual occupant. Hereinafter, for convenience of explanation, this dummy P will be referred to as "occupant P".

The vehicle seat 10 includes a seat cushion 12 that supports the buttocks and thighs of the occupant P. A seat back 14 that supports the back portion (including the lumbar region) of the occupant P is supported at the rear end portion of the seat cushion 12. A headrest 16 that supports the head of the occupant P is attached to the upper end of the seat back 14.

Further, a three-point seat belt device 20 is provided corresponding to the vehicle seat 10 described above. The seatbelt device 20 includes a seatbelt 22 for restraining an occupant. One end 22A of the seat belt 22 is attached to the outer side of the seat cushion 12 in the vehicle width direction (the side surface on the back side of the paper surface in FIG. 1) via the anchor plate 24, and the other end 22B of the seat belt 22 is attached. , It is locked to the spool 32 as the take-up shaft of the seat belt take-up device 30. Further, the intermediate portion of the seat belt 22 is inserted into the shoulder anchor 25 provided on the upper side of the vehicle side portion and folded back. Further, a buckle device 26 is erected on the inner side portion (side surface portion shown in FIG. 1) of the seat cushion 12 in the vehicle width direction. A tongue plate 28 supported in a state of being inserted into an intermediate portion of the seat belt 22 can be engaged with the buckle device 26.

A buckle switch (not shown) is provided inside the buckle device 26. The buckle switch is turned on by engaging the tongue plate 28 and the buckle device 26, and is turned off when the engagement is released. Further, the buckle switch is electrically connected to the ECU 50 described later, and is configured to output an ON signal to the ECU 50 in the ON state and output an OFF signal to the ECU 50 in the OFF state.

In the seatbelt device 20, the seatbelt 22 is attached to the occupant P by engaging the tongue plate 28 with the buckle device 26 while the occupant P is seated on the seat cushion 12. With the tongue plate 28 engaged with the buckle device 26, the portion of the seatbelt 22 located between the tongue plate 28 and the anchor plate 24 is the wrap belt portion 22X, and the tongue plate 28 of the seatbelt 22. The portion located between the shoulder and the shoulder belt portion 25 is referred to as the shoulder belt portion 22Y. The wrap belt portion 22X restrains the waist portion of the occupant P, and the shoulder belt portion 22Y restrains the upper body of the occupant P.

The seatbelt winding device 30 is fixed near the lower end of a center pillar (not shown) that constitutes the vehicle skeleton member. In the seatbelt winding device 30, the spool 32 that winds up the seatbelt 22 is arranged so that the axial direction thereof faces the vehicle front-rear direction. As shown in the partially enlarged view of FIG. 1, the urging mechanism 34 is arranged on one side side (rear side of the vehicle) of the spool 32. The spool 32 is constantly urged in the direction of winding the seat belt 22 by the urging mechanism 34.

The urging mechanism 34 includes a first spring 44 and a second spring 46 as two types of springs, strong and weak, for changing the winding force for winding the seat belt 22 on the spool 32. The second spring 46 is a spring having a weaker urging force than the first spring 44. The urging mechanism 34 is a part of the electric tension reducer 42. The tension reducer 42 includes a clutch and a solenoid 48 (not shown) in addition to the urging mechanism 34. The tension reducer 42 is operated by the solenoid 48 to reduce the torque acting on the spool 32 from the urging mechanism 34 to reduce the winding force for winding the seat belt 22 on the spool 32.

Since the basic configuration of the tension reducer 42 is known, for example, in Japanese Patent Application Laid-Open No. 2013-237395, detailed description thereof will be omitted, but here, as an example, a configuration similar to the configuration described in the above-mentioned publication will be briefly described. explain.

As an example in the present embodiment, the tension reducer 42 is used as an urging means in which the first spring 44 applies an urging force (torque) to the spool 32 in the winding direction, and the second spring 46 is pulled out to the spool 32. It is an urging means that applies urging force (torque) in the direction. The tension reducer 42 has a configuration in which the second spring 46 does not exert an urging force on the spool 32 in the pulling direction when the solenoid 48 is not operating (that is, in the OFF state), and when the solenoid 48 operates. (That is, when it is turned on), the second spring 46 is configured to apply an urging force to the spool 32 in the pull-out direction.

That is, in a state where the occupant P is wearing the seat belt 22, when the solenoid 48 is activated, a part of the torque in the winding direction of the first spring 44 is in the pulling direction of the second spring 46. The torque in the winding direction that the urging mechanism 34 acts on the spool 32 is reduced so as to be offset by the torque of the above.

The operating conditions of the solenoid 48 in this embodiment are different from the operating conditions of the solenoid disclosed in the above-mentioned publication (details will be described later). Further, the torques of the first spring 44 and the second spring 46 are set in a state in which the torques of the two types of springs of the tension reducer, which are generally used at present, are lowered by one rank, respectively, as an example. ..

The seatbelt control device 40 including the tension reducer 42 controls the winding force for winding the seatbelt 22 around the spool 32. The seatbelt control device 40 includes an ECU 50 to which the solenoid 48 is electrically connected. The ECU 50 has a CPU, a ROM, a RAM, a storage, and a communication interface, and each of these components is connected to each other via a bus so as to be communicable with each other. Further, the ECU 50 has a determination unit 52 and a control unit 54 as functional configurations, and each of these functional configurations is realized by the CPU reading and executing a program stored in a ROM or a storage.

The determination unit 52 determines whether or not there is a non-autonomous driving vehicle (manual driving vehicle) around the own vehicle. Supplementally, the determination unit 52 determines whether or not a vehicle exists around the own vehicle based on information acquired from a peripheral recognition sensor (for example, a camera and a radar) (not shown) as an example. Then, when the determination unit 52 determines that a vehicle exists around the own vehicle, the determination unit 52 acquires information on whether or not vehicle-to-vehicle communication has been established between the own vehicle and the surrounding vehicles from a communication device (not shown). However, if the information that the vehicle-to-vehicle communication is established is acquired, it is determined that the other vehicle is in automatic driving, and if the information that the vehicle-to-vehicle communication is not established is acquired, the other vehicle is not. It is determined that the vehicle is in automatic operation (manual operation). As an example, vehicle-to-vehicle communication is performed using DCM (Data Communication Module). Road infrastructure may be used for vehicle-to-vehicle communication.

When the determination unit 52 determines that there is no non-autonomous driving vehicle around the own vehicle, the control unit 54 determines that the non-autonomous driving vehicle exists around the own vehicle, as compared with the case where the determination unit 52 determines that the non-autonomous driving vehicle exists. The solenoid 48 is controlled so that the winding force for winding the belt 22 on the spool 32 is reduced. That is, in the present embodiment, the control unit 54 operates the solenoid 48 when the determination unit 52 determines that there is no non-autonomous driving vehicle around the own vehicle, and applies the torque of the second spring 46 to the spool 32. By doing so, a part of the torque in the winding direction of the first spring 44 is offset by the torque in the pulling direction of the second spring 46.

The seatbelt winding device 30 includes a pretensioner 36 on the other side side (front side of the vehicle) of the spool 32. The pretensioner 36 operates at the time of collision detection to rotate the spool 32 in the direction of winding the seatbelt 22 to apply tension to the shoulder belt portion 22Y.

Next, the operation of the ECU 50 of the seatbelt control device 40 will be described. FIG. 2 is a flowchart showing the flow of control processing by the ECU 50. The processing of the ECU 50 is executed by the CPU reading the program of the belt tension control processing. As an example, when the buckle switch (not shown) is turned on, the execution of the control process shown in FIG. 2 is started.

First, in step 100, the CPU of the ECU 50 determines whether or not a non-autonomous driving vehicle exists around the own vehicle. If the determination in step 100 is affirmed, the process proceeds to step 102, and if the determination in step 100 is denied, the process proceeds to step 104.

In step 102, the CPU of the ECU 50 controls the solenoid 48 to be turned off. As a result, only the torque in the winding direction of the first spring 44 acts on the spool 32. In this state, the winding force for winding the seat belt 22 around the spool 32 (in other words, the belt tension of the seat belt 22) becomes the standard state.

On the other hand, in step 104, the CPU of the ECU 50 controls the solenoid 48 to be turned on. As a result, torque in the drawing direction of the second spring 46 (torque that cancels a part of the torque in the winding direction of the first spring 44) also acts on the spool 32. In this state, the winding force for winding the seat belt 22 around the spool 32 (in other words, the belt tension of the seat belt 22) is low. In this way, if there is no non-autonomous driving vehicle around the own vehicle, it is judged that there is a low possibility that another vehicle will collide with the own vehicle, so the winding force is set to a low state. As a result, the feeling of oppression caused by the seat belt 22 is reduced, and the comfort of the occupant is improved.

Further, when the winding force is lowered from the standard state, the winding force is continuously (gradually) reduced by the first spring 44 and the second spring 46, which are springs, respectively, so that the seat belt 22 The discomfort of the occupant due to the tension of the occupant is reduced.

In the next step 106, the CPU of the ECU 50 determines whether or not the buckle switch is turned off. If the determination in step 106 is affirmed, the process shown in FIG. 2 is terminated, and if the determination in step 106 is denied, the process returns to step 100.

As described above, according to the seatbelt control device 40 of the present embodiment, it is possible to reduce the discomfort of the occupant due to the tension of the seatbelt 22 while demonstrating the occupant protection function.

Further, in the present embodiment, when the winding force for winding the seat belt 22 on the spool 32 is changed, the motor does not need to be energized, and the solenoid 48 is energized, but the current required at that time is 0. It is about 3A, which is much less than when the motor for rotating the spool is energized (about 3A).

Depending on the torque settings of the first spring 44 and the second spring 46, it is possible that the seatbelt 22 is not in close contact with the occupant while the winding force for winding the seatbelt 22 around the spool 32 is reduced. Conceivable. Therefore, as a reference example that is not an embodiment of the present invention, the seatbelt winding device 30 is provided with a rotation angle sensor to monitor the rotation angle of the spool 32, and the seatbelt 22 is pulled out in advance by a predetermined value or more. When the set time has elapsed, the operation of the solenoid 48 may be released to increase the winding force for winding the seatbelt 22 on the spool 32, or the seatbelt 22 may be wound on the spool 32 by the driving force of the motor. You may wind it up.

Although an example of the present invention has been described above, the present invention is not limited to the above, and it goes without saying that the present invention can be variously modified and implemented within a range not deviating from the gist thereof. ..

22 Seat belt 32 Spool (winding shaft)
34 Biasing mechanism 40 Seat belt control device 42 Tension reducer 44 First spring (spring)
46 Second spring (spring)
48 Solenoid 52 Judgment unit 54 Control unit

Claims (1)

It has an urging mechanism equipped with two types of springs, strong and weak, for changing the winding force for winding the seat belt around the winding shaft, and acts on the winding shaft from the urging mechanism by being operated by a solenoid. In a seatbelt control device that controls the winding force by providing an electric tension reducer that reduces the torque to reduce the winding force.
A determination unit that determines whether or not there is a non-autonomous driving vehicle around the own vehicle,
When the determination unit determines that there is no non-autonomous driving vehicle around the own vehicle, the winding force is reduced as compared with the case where the determination unit determines that the non-autonomous driving vehicle exists around the own vehicle. A control unit that controls the solenoid so as to be
Seat belt control device with.

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