Occupant protection device

Abstract

To provide an occupant protection device that can reduce loads that are given to an occupant by a steering part when collision occurs on a vehicle.SOLUTION: An occupant protection device comprises: a steering part 100 storing an airbag AB that inflates and expands toward an occupant P when collision occurs on a vehicle V; a column shaft part 200 through which steering operation in the steering part 100 is transmitted; and a steering connecting part 300 connecting the steering part 100 to the column shaft part 200 so that the parts can be fixed and separated. The steering connection part 300 is configured to include a magnetically attractable connecting / fixing part 310 fixed to a rear side of the vehicle of the column shaft part 200, an electromagnet part 320, provided at a front side of the vehicle of the steering part 100, which is supplied with exciting currents to generate magnetic force, and a driving part 330 that excites the electromagnet part 320 to fix the steering part 100 to the column shaft part 200 or separate the steering part from the column shaft part.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an occupant protection device. [Background technology]

[0002] Passenger protection devices that inflate and deploy an airbag from the steering wheel of a vehicle to protect an occupant seated in the driver's seat when a frontal collision occurs have been put into practical use and are widely used.

[0003] The passenger protection device described above includes a steering column with an impact absorbing mechanism that can move toward the front of the vehicle, a knee airbag device disposed below the steering column, and a column stopper (fixing means) that fixes the steering column so that it does not move toward the front of the vehicle during normal use and releases the fixed state of the steering column when the knee airbag device is activated. The expansion force of the knee airbag bag is used to release the fixed state of the steering column by the column stopper, and no load input from the passenger side to the steering column is required. Therefore, technology that further improves impact absorption performance has been disclosed (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-196734 Summary of the Invention [Problem to be solved by the invention]

[0005] The technology described in Patent Document 1 is a technology that, when a vehicle collision occurs, releases the fixed state of the steering column and moves the steering wheel (steering unit) toward the front of the vehicle, thereby absorbing the impact between the occupant and the steering unit.

[0006] However, in the technology disclosed in Patent Document 1, the angle of the steering unit does not change, so there is a risk that the angle formed by the steering unit and the angle formed by the occupant's chest, etc. will differ. As a result, there is a problem that part of the steering unit may interfere with the occupant's chest, etc., and cause strain on the occupant.

[0007] Therefore, the present invention has been made in consideration of the above-mentioned problems, and aims to provide an occupant protection device that reduces the burden that the steering section imposes on the occupant when a vehicle collision occurs. [Means for solving the problem]

[0008] One or more embodiments of the present invention propose an occupant protection device that includes a steering section that houses an airbag that inflates and deploys toward an occupant when a vehicle collision occurs, a column shaft section that transmits steering operations at the steering section to the front wheels of the vehicle, and a steering connecting section that separably connects the column shaft section and the steering section, wherein the steering connecting section includes a connecting fixing section that is provided on the column shaft section and is capable of being attracted by a magnet, an electromagnet section that is provided on the front side of the steering section of the vehicle, and a drive section that separates the steering section and the column shaft section by exciting the electromagnet section when a collision occurs. [Effects of the Invention]

[0009] According to one or more embodiments of the present invention, the strain that the steering section imposes on the occupant when a vehicle collision occurs can be reduced. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a diagram showing a configuration of an occupant protection device according to a first embodiment of the present invention. [Figure 2] 2 is a cross-sectional view of the occupant protection device according to the first embodiment of the present invention taken along the line AA in FIG. 1 as viewed in the direction of the arrow. [Figure 3] 1A and 1B are diagrams showing the state of the steering section and steering boss section in the passenger protection device according to the first embodiment of the present invention, where (a) is a cross-sectional view showing the state when no collision has occurred in the vehicle, and (b) is a cross-sectional view showing the state when a collision has occurred in the vehicle. [Figure 4] 1A to 1C are cross-sectional views showing, in chronological order, states when a vehicle collision occurs and an occupant sitting in the driver's seat interferes with the steering section in an occupant protection device according to a first embodiment of the present invention. [Figure 5] FIG. 4 is a diagram showing the configuration of an occupant protection device according to a second embodiment of the present invention. [Figure 6] 6 is a cross-sectional view of an occupant protection device according to a second embodiment of the present invention taken along line AA-AA in FIG. 5, as viewed in the direction of the arrows. [Figure 7] 10A and 10B are diagrams showing the state of the steering section and steering boss section in an occupant protection device relating to a second embodiment of the present invention, where (a) is a cross-sectional view showing the state when no collision has occurred in the vehicle, and (b) is a cross-sectional view showing the state when a collision has occurred in the vehicle. [Figure 8] 10A to 10B are cross-sectional views showing, in chronological order, states when a vehicle collision occurs and an occupant sitting in the driver's seat interferes with the steering section in an occupant protection device according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] An occupant protection device 10 and an occupant protection device 10A according to this embodiment will be described with reference to FIGS. In this embodiment, the vehicle V has a driver's seat S1 on the left side when facing the vehicle's traveling direction, and the occupant protection device 10 or occupant protection device 10A is provided in front of the driver's seat S1.

[0012] First Embodiment An occupant protection device 10 according to this embodiment will be described with reference to FIGS. 1 to 4. FIG.

[0013] <Regarding the occupant protection device 10> As shown in FIG. 1, a vehicle V is provided with a driver's seat S1 and a passenger seat S2 where an occupant P sits, on the rear side of a front panel portion FP, and an occupant protection device 10 is provided on the front side of the driver's seat S1. The occupant protection device 10 according to this embodiment includes a steering section 100, a column shaft section 200, and a steering connecting section 300.

[0014] <Regarding the steering unit 100> The steering unit 100 transmits the steering operation of an occupant P seated in the driver's seat S1 to the front wheels of the vehicle V via a column shaft unit 200. The steering unit 100 houses an airbag AB that inflates and deploys toward the occupant P when a collision occurs in the vehicle V. 2, the steering section 100 includes a steering wheel section 110, a steering boss section 120, an upper column shaft cover section 130, a steering spoke section SS, and a horn switch section HS. Inside the steering section 100, on the vehicle front side of the horn switch section HS, an airbag AB is housed that inflates and deploys toward the occupant in the event of a vehicle collision. The steering unit 100 is fixed to a steering connecting unit 300 on the vehicle front side of the steering unit 100 with bolts or the like.

[0015] The steering wheel 110 is a member through which a passenger P seated in the driver's seat S1 inputs steering operations, and is formed in an annular shape from a member such as metal or resin. A plurality of steering spokes SS are connected to the inner periphery of the steering wheel 110, and a horn switch HS is provided in the approximate center of the steering wheel 110 in the vehicle width direction.

[0016] The airbag AB is formed from a member such as a base fabric material and is stored in a folded state inside the horn switch portion HS, for example. When a collision occurs from the front of the vehicle, the airbag AB is inflated and deployed toward the rear of the steering portion 100 by gas supplied from the inflator IF.

[0017] The steering boss portion 120 is fixed to the vehicle front side of the steering portion 100 and is rotatably engaged with the column shaft axis 210 of the column shaft portion 200 via the steering connecting portion 300. The steering boss portion 120 is formed into a cylindrical shape from a member such as metal or resin. The steering portion 100 is fixed to the vehicle rear side of the steering boss portion 120. The steering connecting portion 300 is provided on the vehicle front side of the steering boss portion 120. The steering boss portion 120 is rotatably engaged with the column shaft 210 via a steering connecting portion 300 . A recess is provided on the vehicle rear side of the steering boss portion 120, and an inflator IF that supplies gas when the vehicle V collides is disposed in the recess of the steering boss portion 120.

[0018] The upper column shaft cover portion 130 is formed into a hollow cone shape using a material such as resin, and is fixed to the steering boss portion 120 on the vehicle front side of the steering portion 100 so as to cover the radial outside of the steering boss portion 120. At the front of the vehicle, the apex side of the hollow cone shape of the upper column shaft cover portion 130 slidably engages with the inside of the lower column shaft cover portion 220. The apex side of the cone of the upper column shaft cover portion 130 opens in a substantially circular shape at an engagement portion 230 with the lower column shaft cover portion 220. The upper column shaft cover portion 130 is made of a material that is more flexible than the lower column shaft cover portion 220.

[0019] The inflator IF supplies gas to the airbag AB when a collision occurs in the vehicle V. The inflator IF is joined to the airbag AB on the vehicle rear side of the inflator IF.

[0020] <Regarding the column shaft portion 200> The column shaft portion 200 transmits the steering operation input from the steering wheel portion 110 to the front wheels of the vehicle V via the steering coupling portion 300. The column shaft portion 200 is provided with a column shaft shaft 210 and a lower column shaft cover portion 220. An engagement portion 230 is formed on the vehicle rear side of the lower column shaft cover portion 220.

[0021] The column shaft 210 is a cylindrical rod made of a material such as metal. The column shaft 210 is a rotating shaft that transmits the steering operation input from the steering unit 100 to the front wheels of the vehicle V via the steering boss unit 120 and the steering connecting unit 300. A steering coupling portion 300 is provided on the vehicle rear side of the column shaft shaft 210, and the column shaft shaft 210 is coupled to the steering boss portion 120 via the steering coupling portion 300. A coupling fixing portion 410 of the steering coupling portion 300 is coupled to the vehicle rear side of the column shaft shaft 210.

[0022] The lower column shaft cover portion 220 is formed into a generally hollow cylindrical shape from a material such as metal or resin. The lower column shaft cover portion 220 is fixed to the housing of the vehicle V via a holder or the like (not shown). The column shaft shaft 210 rotatably passes through the interior of the lower column shaft cover portion 220 in the longitudinal direction of the vehicle. An engagement portion 230 with which the upper column shaft cover portion 130 engages is provided on the vehicle rear side of the lower column shaft cover portion 220.

[0023] The engagement portion 230 is made of a metal, resin or other material and is provided on the vehicle rear side of the lower column shaft cover portion 220. The engagement portion 230 is engaged so as to allow the upper column shaft cover portion 130 to rotate in the axial direction of the steering portion 100 and to slide in the front-to-rear direction of the vehicle. The engagement portion 230 may be integrally molded with the lower column shaft cover portion 220.

[0024] <Regarding the steering coupling portion 300> The steering connecting portion 300 connects the steering portion 100 and the column shaft portion 200 in a manner that allows them to be attracted to and separated from each other. The steering connecting portion 300 includes a connecting fixing portion 310 , an electromagnet portion 320 , and a driving portion 330 .

[0025] The connecting and fixing part 310 is fixed to the vehicle rear side of the column shaft part 200. The connecting and fixing part 310 is formed of a member that can be attracted to a magnet, such as a permanent magnet, an iron material, or an electromagnet. The connecting and fixing part 310 is formed, for example, in a substantially cylindrical shape, and has a recess in the end part on the vehicle rear side that fits with the electromagnet part 320 .

[0026] The electromagnet section 320 is fixed to the steering section 100 on the front side of the vehicle, and generates a magnetic force when an excitation current is supplied from the drive section 330 . The electromagnet portion 320 is formed, for example, in a substantially cylindrical shape, and the end portion of the connecting and fixing portion 310 on the vehicle rear side has a protrusion that fits with the electromagnet portion 320 . The electromagnet part 320 is connected to the driving part 330 using, for example, a wire rod WR. Alternatively, the recessed portion of the connecting and fixing portion 310 and the protruding portion of the electromagnet portion 320 may not be formed, and the vehicle rear side surface portion of the connecting and fixing portion 310 and the vehicle front side surface portion of the electromagnet portion 320 may be in close contact with each other.

[0027] The drive unit 330 magnetizes the electromagnet unit 320 to attract or separate the steering unit 100 and the column shaft unit 200 . The driving unit 330 supplies an excitation current to the electromagnet unit 320 via the wire WR, causing the electromagnet unit 320 to generate a magnetic force. 3(a), when the vehicle V has not been hit by a collision, the drive unit 330 generates a magnetic force that attracts the connecting and fixing unit 310 and the electromagnet unit 320, thereby fixing the steering unit 100 and the column shaft unit 200 together. In other words, the rotation axis AX1 of the steering unit 100 and the rotation axis AX2 of the column shaft unit 200 are fixed on the same rotation axis CA. 3(b), when a collision occurs in the vehicle V, the drive unit 330 generates a magnetic force that separates the connecting and fixing unit 310 and the electromagnet unit 320, thereby separating the steering unit 100 and the column shaft unit 200. In other words, when the drive unit 330 separates the connecting and fixing unit 310 and the electromagnet unit 320, the steering unit 100 rotates the rotation axis AX1 around the steering connecting unit 300 in the vertical direction and the width direction of the vehicle freely.

[0028] <Actions and Effects> The operation of the passenger protection device 10 according to this embodiment configured as described above when a collision occurs in the vehicle V will be described with reference to FIGS.

[0029] (If vehicle V has not been hit) When the vehicle V is not in a collision state, the occupant protection device 10 is in a state in which normal steering operation can be performed, as shown in FIG. 3(a). Specifically, the steering section 100 and the column shaft section 200 are fixed together by being attracted to and fitted together by magnetic force between the electromagnet section 320 fixed to the steering section 100 and the connecting and fixing section 310 fixed to the column shaft section 200. In this case, for example, when the connecting and fixing portion 310 is formed by a permanent magnet, the driving portion 330 excites the electromagnet portion 320, and the driving portion 330 generates a polarity that attracts the connecting and fixing portion 310 and the electromagnet portion 320 together. The driving unit 330 attracts the steering unit 100 and the column shaft unit 200, so that the steering unit 100 and the column shaft unit 200 are fixed on the same rotation axis CA.

[0030] Furthermore, the upper column shaft cover portion 130 of the steering unit 100 engages with the lower column shaft cover portion 220 of the column shaft unit 200 at an engagement portion 230. By engaging the upper column shaft cover portion 130 and the lower column shaft cover portion 220, the steering unit 100 and the column shaft unit 200 are fixed onto the same rotation axis CA.

[0031] (If a collision occurs with vehicle V) When a collision occurs in the vehicle V, the occupant protection device 10 operates the inflator IF to supply gas to the airbag AB. The gas supplied to the airbag AB inflates and deploys the airbag AB toward the rear of the vehicle, as shown in Fig. 3(b). The airbag AB inflates and deploys between the occupant P seated in the driver's seat S1 and the steering unit 100. Furthermore, the driving section 330 excites the electromagnet section 320, whereby the occupant protection device 10A separates the steering section 100 and the column shaft section 200.

[0032] Specifically, for example, when the connecting and fixing part 310 is formed of a permanent magnet, the driving part 330 excites the electromagnet part 320, causing the driving part 330 to generate a polarity in the electromagnet part 320 that repels the connecting and fixing part 310 and the electromagnet part 320. The steering part 100, to which the electromagnet part 320 is fixed, moves toward the rear of the vehicle, and the steering part 100 and the column shaft part 200 are separated at the steering connecting part 300. The steering section 100 and the column shaft section 200 are able to rotate freely about any angle around the steering connector 300. In other words, the rotation axis AX1 of the steering section 100 is able to rotate freely about any angle around the steering connector 300, as shown by arrow AR1. The steering section 100 is also able to rotate freely about any angle, as shown by arrows AR2 and AR3.

[0033] On the other hand, when a collision occurs in the vehicle V, the upper body of the occupant P seated in the driver's seat S1 moves toward the front of the vehicle due to the impact of the collision. As shown in FIG. 4(a), the airbag AB inflates and deploys between the occupant P and the steering unit 100 to receive the occupant P.

[0034] When the impact of a collision is large, it is necessary to consider the possibility that the airbag AB may not be fully inflated when receiving the occupant P. Specifically, for example, as shown in Figure 4(b), it is necessary to consider that the angle formed by the upper body of the occupant P and the angle formed by the steering unit 100 are different, and therefore the chest or abdomen of the occupant P may be partially interfered with by the underside of the steering unit 100 when the airbag AB is not fully inflated. At this time, the steering unit 100 is able to rotate freely about the steering connector 300. When the steering unit 100 interferes with the occupant P, the rotation axis AX1 of the steering unit 100 rotates about the steering connector 300 in accordance with the angle formed by the upper body of the occupant P, as shown by arrow BR1. Then, as shown by arrow BR2, the steering unit 100 rotates, and the angle formed by the upper body of the occupant P and the angle formed by the steering unit 100 become substantially the same, so that the occupant protection device 10 receives the upper body of the occupant P with the entire rear side of the steering unit 100. Furthermore, since the upper column shaft cover portion 130 uses a material that is more flexible than the lower column shaft cover portion 220, the upper column shaft cover portion 130 deforms and absorbs the impact when the steering portion 100 and the occupant P interfere with each other.

[0035] That is, the entire rear side of the steering unit 100, the upper column shaft cover 130, and the airbag AB receive the upper body of the occupant P while reducing the impact transmitted to the occupant P. Then, when the vehicle V comes to a stop, the impact absorption by the occupant protection device 10 ends.

[0036] As described above, the occupant protection device 10 according to this embodiment includes a steering unit 100 housing an airbag AB that inflates and deploys toward the occupant P when a collision occurs with the vehicle V, a column shaft unit 200 that transmits steering operations at the steering unit 100 to the front wheels of the vehicle V, and a steering connecting unit 300 that connects the steering unit 100 and the column shaft unit 200 in a manner that allows them to be fixed and separated. The steering connecting unit 300 includes a magnetically attractable connecting fixing unit 310 that is fixed to the rear side of the column shaft unit 200, an electromagnet unit 320 that is provided on the front side of the steering unit 100 and generates a magnetic force when supplied with an excitation current, and a drive unit 330 that fixes or separates the steering unit 100 and the column shaft unit 200 by exciting the electromagnet unit 320. In other words, when no collision occurs with the vehicle V, the electromagnet portion 320 in the steering connecting portion 300 fixed to the steering portion 100 and the connecting fixing portion 310 fixed to the column shaft portion 200 are engaged with each other, so that the steering portion 100 and the column shaft portion 200 are fixed on the same rotation axis CA. Furthermore, the driving unit 330 excites the electromagnet unit 320, so that the driving unit 330 generates a polarity that attracts the electromagnet unit 320 to the connecting and fixing unit 310. The driving unit 330 attracts the steering unit 100 and the column shaft unit 200, so that the steering unit 100 and the column shaft unit 200 are reliably fixed on the same rotation axis CA. When a collision occurs in the vehicle V, the inflator IF is activated, and the inflator IF supplies gas to the airbag AB, causing the occupant protection device 10 to inflate and deploy the airbag AB between the occupant P and the steering unit 100. Furthermore, the drive unit 330 excites the electromagnet unit 320, causing the drive unit 330 to generate a polarity in the electromagnet unit 320 that repels the connecting and fixing unit 310 and the electromagnet unit 320. As a result of the drive unit 330 repelling the steering unit 100 and the column shaft unit 200, the steering unit 100 and the column shaft unit 200 are separated at the steering connecting unit 300, and the steering boss unit 120 and the column shaft unit 200 become able to rotate freely around the steering connecting unit 300. Therefore, when a collision occurs with the vehicle V and the occupant P seated in the driver's seat S1 moves toward the front of the vehicle and interferes with the steering unit 100, the occupant protection device 10 rotates so that the angle formed by the upper body of the occupant P and the angle formed by the steering unit 100 are approximately the same, thereby allowing the occupant protection device 10 to receive the upper body of the occupant P while reducing the impact with the entire rear side of the vehicle of the steering unit 100 and the airbag AB. This reduces the burden that the steering section places on the occupant when the vehicle crashes.

[0037] The occupant protection device 10 according to this embodiment is configured to include a lower column shaft cover portion 220 having a hollow cylindrical shape that is provided on the vehicle front side of the column shaft portion 200 so as to cover the outside of the column shaft portion 200, and an upper column shaft cover portion 130 that is formed in a hollow conical shape using a material different from the material of the lower column shaft cover portion 220, with the apex side of the cone shape engaging with the inside of the lower column shaft cover portion 220 on the vehicle front side. In other words, when no collision has occurred with the vehicle V, the upper column shaft cover part 130, which is formed in a hollow conical shape, engages with the inside of the lower column shaft cover part 220, which has a hollow cylindrical shape, thereby fixing the steering part 100 and the column shaft part 200 on the same rotation axis CA. When a collision occurs in the vehicle V, the upper column shaft cover part 130 is made of a material that is more flexible than the lower column shaft cover part 220, so the upper column shaft cover part 130 deforms and absorbs the impact when the steering part 100 and the occupant P interfere with each other. Therefore, the impact transmitted to the occupant P is reduced by the entire rear side of the vehicle of the steering unit 100 and the airbag AB, and furthermore, by deforming the upper column shaft cover part 130, the upper body of the occupant P can be supported while absorbing the impact when the steering unit 100 and the occupant P interfere with each other. This reduces the burden that the steering section places on the occupant when the vehicle crashes.

[0038] <Second embodiment> An occupant protection device 10A according to this embodiment will be described with reference to FIGS.

[0039] <Regarding the occupant protection device 10A> As shown in FIG. 5, the occupant protection device 10A according to this embodiment includes a steering section 100A, a column shaft section 200A, and a steering connecting section 300.

[0040] <About the steering unit 100A> As shown in FIG. 6, the steering section 100A includes a steering wheel section 110, a steering boss section 120, an upper column shaft cover section 130A, steering spoke sections SS, and a horn switch section HS.

[0041] The upper column shaft cover portion 130A is formed in a hollow cone shape from a material such as resin that is different from that of the lower column shaft cover portion 220. The upper column shaft cover portion 130A is formed, for example, from a material such as resin that is more flexible than that of the lower column shaft cover portion 220. The upper column shaft cover portion 130A is fixed to the steering boss portion 120 so as to cover the radially outer sides of the steering boss portion 120 and the steering connecting portion 300 on the vehicle front side of the steering portion 100A.

[0042] The upper column shaft cover portion 130A is provided with a weakened portion 140 that deforms the hollow conical shape when the vehicle V is hit. Specifically, for example, the fragile portion 140 is provided as a groove portion formed in an annular shape along the inner circumference of the upper column shaft cover portion 130A, between the steering boss portion 120 and the engagement portion 230, on the radially inner side of the upper column shaft cover portion 130A. The fragile portion 140 may be provided in a plurality of locations, or may be provided in only one location.

[0043] <About the column shaft section 200A> The column shaft portion 200A is provided with a constricted portion 240 whose cross-sectional area in the radial direction of the column shaft portion 200A is smaller than the cross-sectional areas of the vehicle rear end and the vehicle front end. The column shaft portion 200A is provided with a column shaft shaft 210A and a lower column shaft cover portion 220.

[0044] The column shaft 210A is a cylindrical rod made of a member such as metal. The column shaft 210A is provided with a constricted portion 240 whose cross-sectional area in the radial direction of the column shaft 210A is smaller than the cross-sectional areas of the vehicle rear end and the vehicle front end. The constricted portion 240 is provided on the vehicle rear side of the column shaft shaft 210A, and ensures a large space between the column shaft shaft 210A and the lower column shaft cover portion 220.

[0045] <Actions and Effects> The operation of the occupant protection device 10A according to this embodiment configured as described above when a collision occurs in the vehicle V will be described with reference to FIGS.

[0046] (If vehicle V has not been hit) When the vehicle V is not in a collision state, the occupant protection device 10A is in a state in which normal steering operation can be performed, as shown in FIG. 7(a). Specifically, the steering section 100A and the column shaft section 200A are fixed together by fitting together the electromagnet section 320 fixed to the steering section 100A in the steering connecting section 300 and the connecting fixing section 310 fixed to the column shaft section 200A. In this case, for example, when the connecting and fixing portion 310 is formed by a permanent magnet, the driving portion 330 excites the electromagnet portion 320, and the driving portion 330 generates a polarity that attracts the connecting and fixing portion 310 and the electromagnet portion 320 together. The driving unit 330 attracts the steering unit 100A and the column shaft unit 200A, so that the steering unit 100A and the column shaft unit 200A are fixed on the same rotation axis CA.

[0047] Furthermore, the lower column shaft cover portion 220 of the column shaft portion 200A is provided with an engagement portion 230 that engages with the upper column shaft cover portion 130 of the steering portion 100A. By engaging the upper column shaft cover portion 130 with the lower column shaft cover portion 220, the steering portion 100A and the column shaft portion 200A are fixed onto the same rotation axis CA.

[0048] (If a collision occurs with vehicle V)

[0049] When a collision occurs in the vehicle V, the passenger protection device 10A activates the inflator IF, which supplies gas to the airbag AB. The gas supplied to the airbag AB inflates and deploys the airbag AB toward the rear of the vehicle, as shown in Fig. 7(b) . The airbag AB inflates and deploys between the occupant P seated in the driver's seat S1 and the steering section 100A.

[0050] Furthermore, the drive unit 330 excites the electromagnet unit 320, whereby the occupant protection device 10A separates the steering unit 100A from the column shaft unit 200A. Specifically, for example, when the connecting and fixing portion 310 is formed by a permanent magnet, the driving portion 330 excites the electromagnet portion 320, causing the driving portion 330 to generate a polarity that repels the connecting and fixing portion 310 and the electromagnet portion 320. The driving unit 330 repels the connecting and fixing unit 310 and the electromagnet unit 320, causing the steering unit 100A and the column shaft unit 200A to separate at the steering connecting unit 300. In other words, the steering unit 100A and the column shaft unit 200A become angularly freely rotatable around the steering connecting unit 300, and the rotation axis AX1 of the steering unit 100A becomes angularly freely rotatable around the steering connecting unit 300 as shown by arrow CR1. The steering unit 100A then becomes angularly freely rotatable as shown by arrows CR2 and CR3.

[0051] On the other hand, when a collision occurs in the vehicle V, the upper body of the occupant P seated in the driver's seat S1 moves toward the front of the vehicle due to the impact of the collision. As shown in FIG. 8(a), the airbag AB inflates and deploys between the occupant P and the steering section 100A to receive the occupant P.

[0052] When the impact of a collision is large, it is necessary to consider the possibility that the airbag AB may not be fully inflated when receiving the occupant P. Specifically, for example, as shown in Figure 8(b), it is necessary to consider that the angle formed by the upper body of the occupant P and the angle formed by the steering unit 100A are different, and therefore the chest or abdomen of the occupant P may be partially interfered with by the underside of the vehicle of the steering unit 100A when the airbag AB is not fully inflated. At this time, the steering unit 100A becomes freely rotatable about the steering connector 300. When the steering unit 100A interferes with the occupant P, the rotation axis AX1 of the steering unit 100A rotates about the steering connector 300 in accordance with the angle formed by the upper body of the occupant P, as shown by the arrow DR1. Then, as shown by the arrow DR2, the steering unit 100A rotates, and the angle formed by the upper body of the occupant P and the angle formed by the steering unit 100A become substantially the same, so that the occupant protection device 10A receives the upper body of the occupant P with the entire rear side of the steering unit 100A.

[0053] Furthermore, the upper column shaft cover portion 130 uses a material that is more flexible than the lower column shaft cover portion 220, and is provided with the fragile portion 140, so that the upper column shaft cover portion 130 deforms without resistance when the steering portion 100A interferes with the occupant P. Therefore, the upper column shaft cover portion 130 does not restrict the steering portion 100A from rotating freely about the steering connecting portion 300. At this time, the column shaft shaft 210A is provided with a constricted portion 240. The deformed upper column shaft cover portion 130A moves without resistance into the space defined by the constricted portion 240, and the upper column shaft cover portion 130 absorbs the impact transmitted to the occupant P.

[0054] That is, the entire rear side surface of the steering section 100A, the upper column shaft cover section 130A, and the airbag AB receive the upper body of the occupant P while reducing the impact transmitted to the occupant P. Then, when the vehicle V comes to a stop, the impact absorption by the occupant protection device 10A ends.

[0055] As described above, in the occupant protection device 10A according to this embodiment, the upper column shaft cover portion 130A is provided with the weakened portion 140 that deforms the hollow cone shape when the vehicle V is hit. In other words, when a collision occurs in the vehicle V and the steering unit 100A interferes with the occupant P, the steering unit 100A rotates so that the angle formed by the upper body of the occupant P and the angle formed by the steering unit 100A become approximately the same. At this time, since the upper column shaft cover part 130A is provided with the weakened part 140, the upper column shaft cover part 130 deforms while absorbing the impact when the steering part 100A interferes with the occupant P. Therefore, the upper column shaft cover part 130 does not restrict the steering part 100A from rotating freely about the steering connecting part 300. Therefore, when a collision occurs with the vehicle V and the steering unit 100A interferes with the occupant P, the steering unit 100A rotates so that the angle formed by the upper body of the occupant P and the angle formed by the steering unit 100A become approximately the same, and the upper column shaft cover unit 130 deforms while absorbing the impact, so that the occupant protection device 10A can absorb and receive the impact on the upper body of the occupant P with the entire rear side of the vehicle of the steering unit 100A, and absorb the impact transmitted to the occupant P. This reduces the burden that the steering section places on the occupant when the vehicle crashes.

[0056] In the occupant protection device 10A according to this embodiment, the column shaft portion 200A is provided with a constricted portion 240 whose radial cross-sectional area is smaller than the cross-sectional areas of the vehicle rear end and the vehicle front end. In other words, when a collision occurs with the vehicle V, the upper column shaft cover portion 130 uses a material that is more flexible than the lower column shaft cover portion 220, and is provided with the fragile portion 140, so that when the steering portion 100A and the occupant P interfere with each other, the upper column shaft cover portion 130 deforms while absorbing the impact. At this time, the column shaft shaft 210A is provided with a constricted portion 240. The deformed upper column shaft cover portion 130A enters without resistance into the space defined by the constricted portion 240. As the deformed upper column shaft cover portion 130A enters without resistance into the space defined by the constricted portion 240, the upper column shaft cover portion 130 absorbs the impact that would be transmitted to the occupant P. Therefore, the deformed upper column shaft cover portion 130A enters the space defined by the constricted portion 240 without resistance, and the upper column shaft cover portion 130 is able to absorb the impact transmitted to the occupant P. This reduces the burden that the steering section places on the occupant when the vehicle crashes.

[0057] The above describes in detail an embodiment of the present invention with reference to the drawings, but the specific configuration is not limited to this embodiment, and includes designs within the scope of the gist of the present invention. [Explanation of symbols]

[0058] 10;Occupant protection device 10A; Occupant protection device 100; Steering section 100A; Steering section 110: Steering wheel 120: Steering boss 130: Upper column shaft cover 130A: Upper column shaft cover 140;Weak part 200: Column shaft section 210: Column shaft axis 210A; Column shaft axis 220: Lower column shaft cover 230 Engagement part 240; Neck 300: Steering linkage 310;Connection fixing part 320;Electromagnet part 330 Drive unit AB; Airbag IF; Inflator V; Vehicle

Claims

1. a steering section that houses an airbag that inflates and deploys toward an occupant when a vehicle collision occurs; a column shaft portion that transmits a steering operation of the steering portion to front wheels of the vehicle; a steering coupling portion that fixedly and separably couples the steering portion and the column shaft portion; Including, The steering coupling portion is a connecting and fixing portion that is fixed to the rear side of the column shaft portion and can be attracted by a magnet; an electromagnet unit provided on a front side of the steering unit and configured to generate a magnetic force when supplied with an excitation current; a drive unit that fixes or separates the steering unit and the column shaft unit by exciting the electromagnet unit; An occupant protection device comprising:

2. a lower column shaft cover portion having a hollow cylindrical shape provided on the vehicle front side of the column shaft portion so as to cover the outside of the column shaft portion; an upper column shaft cover portion that is fixed to the vehicle front side of the steering portion and is formed in a hollow cone shape using a member different from the member of the lower column shaft cover portion, with the apex of the cone shape engaging with the inside of the lower column shaft cover portion at the vehicle front side; 2. The passenger protection device according to claim 1, further comprising:

3. 3. The passenger protection device according to claim 2, wherein the upper column shaft cover portion is provided with a weakened portion that deforms the hollow cone shape when a collision occurs to the vehicle.

4. 4. The occupant protection device according to claim 3, wherein the column shaft portion is provided with a constricted portion having a cross-sectional area in the radial direction of the column shaft portion that is smaller than the cross-sectional areas of the vehicle rear end and the vehicle front end.

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