JP2008189278A - Steering device - Google Patents

Abstract

To provide a steering apparatus with a built-in airbag having a new structure capable of extending a distance in which a driver is allowed to move when the airbag is deployed.
A steering device 22 includes a steering wheel 12 fixed to an upper end of an upper portion of a steering shaft, a wheel pad 38 disposed on an inner peripheral side of the steering wheel 12 and containing an airbag therein, and a wheel pad 38. Is provided at a predetermined height from the tip of the steering shaft. The support mechanism 34 retracts the wheel pad 38 toward the steering shaft when the airbag 14 is deployed, and extends the movement allowable distance of the driver's chest that moves toward the steering shaft as the deployed airbag contracts. To reduce the impact force applied to the driver.
[Selection] Figure 4

Description

  The present invention relates to a steering device, and more particularly to an improvement of a steering device with a built-in airbag capable of extending a driver's chest movement allowable distance when the airbag is deployed.

  In recent years, an increasing number of vehicles have an air bag system as a standard equipment. The airbag system inflates the airbag instantaneously between the driver and the steering wheel when a large impact force is applied to the vehicle due to a collision, etc., and pushes the airbag to the driver who is thrown forward. It is a device that reduces damage taken by the driver by crushing.

  Specifically, when a vehicle traveling forward collides with an object, the driver is thrown forward although it is restrained by the seat belt. The airbag detects a vehicle collision with an impact sensor or the like and energizes and ignites the inflator, thereby sending gas into the airbag and inflating and deploying the airbag. The chest of the driver thrown forward moves further forward while crushing the inflated airbag and contacts the steering wheel. When the kinetic energy of the forward movement of the driver is large, the chest moves further forward while deforming the steering wheel. At this time, the crushing operation of the airbag and the deformation operation of the steering wheel absorb the kinetic energy of the driver's forward movement, so that the impact received by the driver can be reduced.

  By the way, the airbag is supported by a support formed of a metal plate or the like fixed together with the steering wheel at the tip of the steering shaft. Further, an inflator that generates gas for inflating the airbag is disposed on the support. Therefore, if the forward kinetic energy is not completely absorbed by the operation of the airbag or the like, the driver may be restricted from moving due to contact with the airbag support and may receive an impact. Therefore, in a vehicle equipped with an airbag, a structure is desired in which the distance that the movement of the driver's chest is allowed when the airbag is deployed is extended to avoid contact between the airbag support and the driver as much as possible. It is rare.

In Patent Document 1, when a driver collides with a rim or spoke on the front side of the steering wheel and a load is applied, a support body that supports the airbag device is pulled in along with the deformation of the rim or spoke, thereby driving the vehicle. A steering wheel is disclosed that extends the distance traveled until a person contacts the airbag support. Further, as another device for extending the driver's chest movement allowable distance, a structure in which the steering column is pulled in front of the vehicle when the vehicle collides has been proposed. For example, Patent Document 2 discloses a steering column device that, when a vehicle collision is detected, first retracts the steering column to the front of the vehicle and then deploys the airbag.
JP-A-11-278282 JP 2002-114159 A

  However, in the steering wheel described in Patent Document 1, when the driver collides with the rim and the spoke and the rim and the spoke are deformed, the support body is pulled in. Therefore, when the driver collides directly with the support body. The driver's chest movement allowable distance is not extended. Further, in the steering column device described in Patent Document 2, a mechanism for retracting the steering column forward prior to deployment of the airbag needs to be provided in the vicinity of the column. In many cases, it is difficult to attach to the camera from the viewpoint of space.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a steering apparatus with a built-in airbag having a new structure capable of extending a distance in which a driver can move when the airbag is deployed. It is in.

  In order to solve the above-described problems, a steering device according to an aspect of the present invention includes a steering wheel fixed to an upper end portion of a steering shaft, an inner peripheral side of the steering wheel, and an airbag accommodated therein. A wheel pad; and a support mechanism that supports the wheel pad at a predetermined height from a tip of the steering shaft. The support mechanism pulls the wheel pad toward the steering shaft when the airbag is deployed.

  According to this aspect, when the airbag is deployed, the wheel pad is pulled toward the steering shaft, so that it is possible to extend the distance that allows the driver to move by the distance of the wheel pad at that time. .

  The support mechanism moves the connection member when the airbag is deployed, and a connection member that is coupled to the steering wheel and the wheel pad so as to be a predetermined distance when the airbag is not deployed. And a moving mechanism. The connecting member has a second fastening portion fastened to the wheel pad with respect to a first fastening portion fastened to the steering wheel while being moved by the moving mechanism when the airbag is deployed. You may guide at least any one of this 1st fastening part and this 2nd fastening part so that it may approach.

  As the connection member, for example, a metal plate-like member can be used. For example, the connecting member is disposed in a space between the steering wheel and the wheel pad, and the steering wheel and the wheel pad are fastened or fitted to the connecting member, so that the wheel can be used when the airbag is not deployed. The pad and the steering wheel are held at a predetermined distance. When the airbag is deployed, the connecting member is moved by the moving mechanism so that the second fastening portion fastened to the wheel pad approaches the first fastening portion fastened to the steering wheel. , And guides at least one of the first fastening portion and the second fastening portion. Thus, when the airbag is deployed, the wheel pad is drawn toward the steering wheel by a simple movement of moving the connecting member, in other words, the wheel pad is drawn toward the steering shaft, so that the driver contacts the wheel pad. The movement allowable distance that is allowed to move up to is extended. The movement of the connecting member may be performed in association with, for example, an airbag deployment operation. The timing of movement of the connecting member may be selected in accordance with the running state of the vehicle, the performance of the airbag, the structure, and the like. For example, the connecting member may be moved prior to the deployment of the airbag. The connecting member may be moved after the airbag is deployed.

  The connecting member may include a first guide portion that guides the first fastening portion, and a second guide portion that guides the second fastening portion. The first guide part and the second guide part may be formed so that a guide direction of the first guide part and a guide direction of the second guide part intersect each other. Here, as a guide part, the groove | channel and convex part which were formed in the surface of a metal plate-shaped member may be sufficient, for example. Thereby, since the 1st guide part and the 2nd guide part are formed so that the guide direction of the 1st guide part and the guide direction of the 2nd guide part may intersect, a connection member is predetermined. When it moves to a direction, the 1st fastening part guided by the 1st guide part and the 2nd fastening part guided by the 2nd guide part can be brought close gradually.

  The moving mechanism may include a gas generating device that generates gas and a piston that is pushed out by introduction of the generated gas and moves the connecting member. Thereby, since a big force can be generated instantaneously with a simple configuration, the connecting member can be moved smoothly and reliably. Therefore, the wheel pad can be reliably pulled toward the steering shaft when the airbag is deployed.

  ADVANTAGE OF THE INVENTION According to this invention, the distance which a driver | operator's movement is permitted at the time of airbag deployment can be extended.

  The best mode for carrying out the present invention will be described below in detail with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and repeated descriptions are omitted as appropriate.

  The steering device with a built-in airbag according to the present embodiment draws the wheel pad that houses the airbag toward the steering shaft when the airbag is deployed. As a result, the movement allowable distance of the chest of the driver who moves toward the wheel pad as the deployed airbag contracts can be substantially extended, so that the impact force applied to the driver can be reduced.

  FIG. 1 is a schematic diagram for explaining a state in which an airbag 14 is deployed in a vehicle 10 on which the airbag built-in steering device of the present embodiment is mounted. FIG. 2 is a block diagram illustrating a system related to the deployment of the airbag in the steering apparatus with a built-in airbag according to the present embodiment. In addition to the driver seat, the airbag includes a passenger seat, a side window, a rear seat, and the like. In the present embodiment, the airbag 14 for the driver seat built in the steering wheel 12 is particularly focused. To do. The airbag 14 is made of, for example, a silicon-coated nylon cloth, and is inflated and deployed instantaneously with, for example, nitrogen gas generated by an inflator.

  The airbag device that deploys the airbag 14 is mainly configured by a control circuit that controls the operation of the airbag 14, a sensor that detects that an impact such as a collision has been applied to the vehicle, a drive circuit that deploys the airbag 14, and the like. Is done. As sensors for detecting an impact, for example, there are two satellite sensors 16 provided on the left and right of the front portion of the vehicle 10 and a floor sensor 15 disposed on the floor. The satellite sensor 16 mainly detects a deceleration applied to the vehicle 10 and outputs a time-series deceleration signal corresponding to the deceleration. The floor sensor 15 is an acceleration sensor that measures an impact applied to the vehicle 10 and transmitted through the vehicle body. Specifically, the floor sensor 15 measures a deceleration applied to the vehicle in the front-rear direction as needed, and measures the measurement. Output the value as a signal.

  When the satellite sensor 16 and the floor sensor 15 detect that an impact greater than a predetermined threshold (for example, an impact that applies a force of 1 kN in the axial direction of the steering shaft 20) is applied to the vehicle 10, the CPU 17 and the storage circuit The control circuit 19 including the above transmits an ignition signal to the inflator 36 of the airbag 14. The inflator 36 that has received the ignition signal sends nitrogen gas into the airbag 14 that has been ignited and folded.

  FIG. 3 is a top view of the air bag built-in steering device of the present embodiment as viewed from above. The airbag 14 is accommodated in a wheel pad 38 positioned substantially at the center of the steering wheel 12 and expands to fill a space between the steering wheel 12 and the driver 18 as shown in FIG. 1 when deployed. .

  For example, when the vehicle 10 collides with an obstacle in front of the vehicle 10 and receives an impact, the driver 18 starts moving so as to be thrown out toward the front (the front in the axial direction of the steering shaft 20). Subsequently, the driver 18 comes into contact with the airbag 14 deployed by impact, and continues to move further forward while the airbag 14 is crushed. Furthermore, as the forward movement proceeds, the driver 18 contacts the steering wheel 12. The steering wheel 12 has a structure that is easily deformed in order to reduce damage to the driver 18 when the airbag 14 is deployed.

  Part or all of the kinetic energy of the driver 18 is absorbed by the crushing operation of the airbag 14 and the deformation operation of the steering wheel 12. However, when kinetic energy remains, the driver 18 continuously moves forward in the axial direction of the steering shaft 20. Since the airbag 14 is instantly inflated when deployed, the airbag 14 is housed in the wheel pad 38 while being supported by a bag holder made of metal or the like having sufficient rigidity. Therefore, if the driver 18 continues to move forward, the possibility of damaging the driver 18 due to contact with the bag holder inside the wheel pad 38 increases. Therefore, the airbag built-in steering device of the present embodiment has a structure that can extend the chest movement allowable distance of the driver 18 when the airbag 14 is deployed.

  Hereinafter, an outline of the steering apparatus with built-in airbag (hereinafter referred to as a steering apparatus) 22 according to the present embodiment will be described with reference to FIGS. 4 is a cross-sectional view taken along line AA of the steering apparatus shown in FIG. FIG. 5 is a side view of the steering device shown in FIG. 3 when viewed from the B direction. FIG. 6 is a side view of the steering device shown in FIG. 3 when viewed from the C direction. FIG. 7 is a side view of the steering device shown in FIG. 3 when viewed from the D direction.

  As shown in FIG. 4, the steering wheel 12 is fixed to the upper end portion of the steering shaft 20 by a fastening member such as a nut 24. The steering wheel 12 includes a ring-shaped steering rim 26, two spokes 28 that support the steering rim 26, and a boss 30 to which the spokes 28 are connected and fixed to the steering shaft 20. In the steering rim 26 and the spoke 28, resin members 26b and 28b are provided around the core bars 26a and 28a. The resin members 26b and 28b absorb the impact at the time of collision, and improve the feeling of touch and appearance. A wheel pad 38 in which the airbag 14 is housed is disposed in the central portion on the inner peripheral side of the steering rim 26.

  A boss 30 of the steering wheel 12 is fixed to the upper end portion of the steering shaft 20. A support mechanism 34 is fixed to the boss 30 to support a wheel pad 38 that houses a bag holder 32 that supports the airbag 14 at a predetermined height from the tip position of the steering shaft 20. As shown in FIG. 4, the airbag 14 is folded compactly when stored, and an open end is fixed on the bag holder 32. The bag holder 32 is a dish-shaped member formed of a metal plate or the like so as to withstand a reaction force when the airbag 14 is deployed. An inflator 36 is disposed on the bag holder 32.

  When the vehicle 10 receives an impact of a predetermined value or more, the inflator 36 is ignited by an electric signal and instantaneously generates a large amount of nitrogen gas to deploy the airbag 14. The airbag 14 is covered with a pad cover 38a formed of resin or the like, and forms a wheel pad 38 as a whole. The pad cover 38 a causes a crack set in advance when the airbag 14 is deployed to tear, and deploys the airbag 14 between the steering wheel 12 and the driver 18. The air bag 14 is formed with a small hole for extracting air, and when the driver 18 comes into contact, the nitrogen gas is released from the hole and contracts while supporting the driver 18.

  The support mechanism 34 is configured to retract the wheel pad 38 toward the steering shaft 20 when the airbag 14 is deployed. As will be described in detail later, the support mechanism 34 allows the wheel pad 38 supported by the support mechanism 34 to escape in the axial direction of the steering shaft 20, thereby reducing damage that the driver 18 receives due to contact with the bag holder 32. can do. In addition, since the driver | operator 18 is restrained by the seat belt, the moving amount | distance ahead of the axial direction of the steering shaft 20 is physically restrict | limited. Therefore, the damage to the driver 18 can be remarkably reduced by letting the obstacle in contact with the driver 18 as little as possible in the axial direction of the steering shaft 20. Thus, when the airbag 14 is deployed, the support mechanism 34 can greatly contribute to the safety improvement of the driver 18 by pulling the wheel pad 38 in the axial direction of the steering shaft 20. In particular, when a structure such as an electric power steering unit is disposed around the steering shaft 20 and the contraction structure of the steering shaft 20 is difficult to employ, the contraction structure can be realized by the steering device 22 according to the present embodiment. As a result, the design freedom of the vehicle 10 can be improved, and the space around the steering shaft 20 can be effectively used.

  Specifically, the support mechanism 34 according to the present embodiment is a pull-in plate that functions as a connecting member that is connected to the steering wheel 12 and the wheel pad 38 so as to have a predetermined distance when the airbag 14 is not deployed. 40 and a moving mechanism 42 that moves the retracting plate 40 when the airbag 14 is deployed. The drawing plate 40 is a plate-shaped metal member as shown in FIGS. Guide grooves 40 b 1 and 40 b 2 are formed on the side surface 40 a of the drawing plate 40 obliquely with respect to the axial direction of the steering shaft 20.

  As shown in FIG. 6, four support members 44 are provided on the top of the boss 30 of the steering wheel 12, and a hole (not shown) is provided at the end of each support member 44. The pin 48 is inserted into the hole of the support member 44, and the leading end of the pin 48 is fitted into the guide groove 40b1 while the head of the pin 48 tightens the support member 44. 44 is fastened. That is, the retracting plate 40 of the present embodiment is fastened to the steering wheel 12 by the first fastening portion 56 including the support member 44 and the pin 48 as shown in FIG. In addition, by forming a thread on the pin 48 and a thread groove in the hole of the support member 44, the pin 48 can be prevented from dropping from the hole due to an impact when the retracting plate 40 is moved.

  On the other hand, as shown in FIG. 6, four support members 46 are provided at the bottom of the wheel pad 38, and holes (not shown) are formed at the ends of the support members 46. The pin 49 is inserted into the hole of the support member 46, and the leading end of the pin 49 is fitted into the guide groove 40b2 while the head of the pin 49 tightens the support member 46, so that the retracting plate 40 and the support member 46 is fastened. That is, the retracting plate 40 of the present embodiment is fastened to the wheel pad 38 by the second fastening portion 58 including the support member 46 and the pin 49 as shown in FIG. By forming a thread on the pin 49 and a thread groove in the hole of the support member 46, it is possible to prevent the pin 49 from falling off the hole due to an impact when the retracting plate 40 is moved.

  Therefore, when the airbag 14 is not deployed, the pull-in plate 40 is fixed to the support member 44 and the support member 46, whereby the steering wheel 12 and the wheel pad 38 are held at a predetermined distance.

  Next, the moving mechanism 42 will be described with reference to FIG. 4 and FIG. The moving mechanism 42 accommodates the gas generator 50 that generates gas, the piston 52 that is pushed out by introduction of the generated gas to move the pull-in plate 40, the gas generator 50 and the piston 52, and is fixed to the boss 30. And a rectangular parallelepiped casing 54. The housing 54 is provided with a through hole 54 a in a direction perpendicular to the axial direction of the steering shaft 20. And the piston 52 is arrange | positioned at the side near the drawing-in plate 40 inside the through-hole 54a, and the gas generator 50 is arrange | positioned at the rear end side on the opposite side to the front end side of the piston 52 facing the drawing-in plate 40.

  Next, a mechanism in which the support mechanism 34 pulls the wheel pad 38 toward the steering shaft 20 will be described. FIG. 8 is a side view of the steering device with the wheel pad retracted when the airbag is deployed. As described above, when the floor sensor 15 or the satellite sensor 16 detects that an impact of a predetermined threshold value or more is applied to the vehicle 10, the control circuit 19 causes the gas generator 50 to Send an ignition signal. Receiving the ignition signal, the gas generator 50 is ignited by the electric signal and instantly generates a large amount of gas. Thereby, since a big force can be generated instantaneously with a simple configuration, the retracting plate 40 can be moved smoothly and reliably.

  As shown in FIG. 7, the piston 52 is pushed in the direction of the arrow X by the pressure of the generated gas and presses the drawing plate 40. As a result, the retracting plate 40 which has been fixed by the first fastening portion 56 and the second fastening portion 58 until then starts to move. The pull-in plate 40 moves while the guide groove 40b1 guides the first fastening portion 56 and the guide groove 40b2 guides the second fastening portion 58. The guide groove 40b1 as the first guide part and the guide groove 40b2 as the second guide part are formed so that the guide direction Y1 of the guide groove 40b1 and the guide direction Y2 of the guide groove 40b2 intersect. When the retracting plate 40 moves in the X direction, as shown in FIG. 8, the first fastening portion 56 guided by the guide groove 40b1 and the second fastening portion 58 guided by the guide groove 40b2 are gradually formed. Will approach.

  As a result, when the airbag 14 is deployed, the wheel pad 38 is pulled toward the steering wheel 12 by a simple movement of moving the retracting plate 40, in other words, the wheel pad 38 is pulled toward the steering shaft 20. The movement allowable distance that is allowed to move until the wheel pad 38 contacts the wheel pad 38 is extended.

  As shown in FIGS. 5 and 7, the support mechanism 34 according to the present embodiment includes a first fastening portion 56 and a second fastening portion 58 between the support members 44 and 46 and the pins 48 and 49. The plate-shaped regulation plate 60 which regulates the movement of is provided. The restriction plate 60 is fixed to the boss 30 and has an opening groove 60a formed in the axial direction of the steering shaft. The restriction plate 60 restricts the first fastening portion 56 and the second fastening portion 58 from moving in the X direction and guides the second fastening portion 58 in a direction parallel to the longitudinal direction of the opening groove 60a. . Thereby, the support mechanism 34 can be reliably pulled toward the steering shaft without tilting the wheel pad 38 when the airbag is deployed.

  Thus, according to the steering device 22 of the present embodiment, the chest movement allowable distance of the driver 18 can be quickly extended when the airbag 14 is deployed, so that the impact force received by the driver 18 can be reduced.

  The driving source of the moving mechanism 42 is arbitrary as long as the driving reaction speed can be ensured, and may be liquid pressure driving or motor driving in addition to gas pressure driving, and the same effects as in the present embodiment can be obtained.

  The present invention has been described with reference to the above-described embodiment. However, this is an exemplification, and the present invention is not limited to the above-described embodiment, and appropriately combines the configurations of the embodiments. And those substituted are also included in the present invention. Various modifications such as design changes can be added to each embodiment based on the knowledge of those skilled in the art, and the embodiments to which such modifications are added are also included in the scope of the present invention. sell.

It is a mimetic diagram explaining the state where an air bag developed in vehicles which mount a steering device with a built-in air bag of this embodiment. It is a block diagram explaining the system in connection with expansion | deployment of the airbag in the steering device with a built-in airbag of this Embodiment. It is the top view which looked at the steering device with a built-in airbag of this embodiment from the upper part. It is AA sectional drawing of the steering apparatus shown in FIG. It is a side view at the time of seeing the steering device shown in Drawing 3 from the B direction. It is a side view at the time of seeing the steering device shown in FIG. 3 from the C direction. It is a side view at the time of seeing the steering device shown in Drawing 3 from the D direction. It is a side view of a steering device in the state where a wheel pad was pulled in at the time of air bag deployment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Vehicle, 12 Steering wheel, 14 Air bag, 20 Steering shaft, 22 Steering device, 30 Boss, 32 Bag holder, 34 Support mechanism, 36 Inflator, 38 Wheel pad, 40 Retraction plate, 40b1 Guide groove, 40b2 Guide groove, 42 Moving mechanism, 44 support member, 46 support member, 48 pin, 49 pin, 50 gas generator, 52 piston, 56 first fastening portion, 58 second fastening portion.

Claims (4)

A steering wheel fixed to the upper end of the steering shaft;
A wheel pad disposed on the inner peripheral side of the steering wheel and containing an airbag therein;
A support mechanism for supporting the wheel pad at a predetermined height from the tip of the steering shaft,
The steering device according to claim 1, wherein the support mechanism pulls the wheel pad toward the steering shaft when the airbag is deployed. The support mechanism is
Connecting members connected to each other so that the steering wheel and the wheel pad are at a predetermined distance when the airbag is not deployed,
A moving mechanism for moving the connecting member when the airbag is deployed,
The connecting member has a second fastening portion fastened to the wheel pad with respect to a first fastening portion fastened to the steering wheel while being moved by the moving mechanism when the airbag is deployed. The steering apparatus according to claim 1, wherein at least one of the first fastening portion and the second fastening portion is guided so as to approach the steering device. The connecting member includes a first guide part that guides the first fastening part, and a second guide part that guides the second fastening part,
The first guide part and the second guide part are formed so that a guide direction of the first guide part and a guide direction of the second guide part intersect each other. Item 3. The steering device according to Item 2.   4. The steering apparatus according to claim 2, wherein the moving mechanism includes a gas generator that generates gas and a piston that is pushed out by introduction of the generated gas and moves the connecting member. 5.

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