Vehicle front structure

Abstract

To improve protection performance with respect to a collision body while costs are reduced.SOLUTION: In a vehicle front structure S, a bladder 54 is provided on a rear side of a bumper cover 20 and is supported by a movable plate 52 from the back. The movable plate 52 is movably connected to an air guide 30. When a head-on collision between a vehicle V and a pedestrian (a collision body) occurs, a brake system of the vehicle V activates causing a movable plate 52 moving forward by an inertia to press and deform the bladder 54 boosting an air pressure inside the bladder 54. Thus, the bladder 54 whose internal pressure has risen can receive the pedestrian entering a front end part of the vehicle V. That is, the pedestrian can be received while the internal pressure of the bladder 54 which is filled with the air is increased. As a result, it is possible to absorb a collision energy of the pedestrian without using a gas generator for expanding the bladder 54.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a vehicle front structure. [Background technology]

[0002] In the vehicle front structure described in Patent Document 1 below, a pair of upper and lower airbags are provided on the upper and lower sides of the bumper beam. For example, in the event of a frontal collision between the vehicle and a pedestrian (colliding object), the airbags are inflated and deployed on the upper and lower sides of the bumper beam and are disposed on the vehicle front side of an auxiliary device such as a condenser. This allows the airbag to absorb the collision energy of the pedestrian (colliding object) colliding with the bumper cover while being supported from the rear side of the vehicle by the auxiliary device. This improves the protection performance against the pedestrian (colliding object). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-220766 A Summary of the Invention [Problem to be solved by the invention]

[0004] Here, the above vehicle front structure has room for improvement in the following respects. That is, the above vehicle front structure requires an inflator (gas generating device) for inflating and deploying the airbag, which tends to increase the cost of the vehicle front structure. For this reason, it is desirable to have a vehicle front structure that can increase protection performance against a colliding object during a collision while reducing costs.

[0005] In consideration of the above, an object of the present invention is to provide a vehicle front structure that can enhance protection performance against a collision object while reducing costs. [Means for solving the problem]

[0006] One or more embodiments of the present invention are a vehicle front structure comprising: a bumper cover provided at the front end of the vehicle and extending in the vehicle width direction; a hollow impact absorbing member provided on the vehicle rear side of the bumper cover and filled with gas; and a support mechanism that supports the impact absorbing member from the rear side of the vehicle, is movably connected to a vehicle body member, and moves toward the front side of the vehicle due to inertial force, compressing the impact absorbing member. Effect of the Invention

[0007] According to one or more embodiments of the present invention, it is possible to improve protection against a colliding object while reducing costs. [Brief description of the drawings]

[0008] [Figure 1] 1 is a side view seen from the left side of the vehicle, showing a schematic view of a front end portion of a vehicle to which a vehicle front structure according to an embodiment of the present invention is applied. [Diagram 2] 2 is a plan view of the front end portion of the vehicle shown in FIG. 1 as viewed from above the vehicle. [Diagram 3] 11 is a side view showing a state in which a bladder is compressed and deformed by a moving member that rotates toward the front of the vehicle due to an inertial force toward the front of the vehicle at the early stage of a frontal collision between a vehicle and a pedestrian. FIG. [Figure 4] 4 is a side view showing a state in which the bladder has been further compressed and deformed in the front-rear direction by the bumper cover and the moving member from the state shown in FIG. 3, and the leg sweep device has been operated by the compressed air in the bladder. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a vehicle (automobile) V to which a vehicle front structure S according to this embodiment is applied will be described with reference to the drawings. In the drawings, the front side of the vehicle V is indicated by an arrow FR, the upper side of the vehicle is indicated by an arrow UP, and the left side of the vehicle (one side in the vehicle width direction) as viewed from above the vehicle is indicated by an arrow LH. In addition, in the following description, when the up-down, front-rear, and left-right directions are used, they refer to the up-down direction of the vehicle, the front-rear direction of the vehicle, and the left-right direction of the vehicle, unless otherwise specified.

[0010] 1 and 2, the vehicle front structure S is applied to the front end of a vehicle V. The vehicle front structure S includes a pair of left and right front side frames 10, a bumper beam 14, a radiator support 16, an absorber 18, a bumper cover 20, an air guide 30 as a vehicle body member, a plurality of leg sweep devices 40 as protective devices, and an impact absorbing mechanism 50.

[0011] (Regarding front side frame 10) The front side frames 10 are formed in a hollow, generally rectangular columnar shape extending in the front-rear direction, and are disposed on both left and right sides (both sides in the vehicle width direction) of the front of the vehicle V. Crash boxes 12 are provided on the front sides of the front side frames 10. The crash boxes 12 are formed in a generally rectangular tubular shape with the axial direction extending in the front-rear direction, and the rear end portions of the crash boxes 12 are joined to the front end portions of the front side frames 10. Front wheels 28 are provided on the left and right outer sides of the front end portions of the front side frames 10.

[0012] (About Bumper Beam 14) The bumper beam 14 extends in the left-right direction and has a generally rectangular closed cross-sectional shape when viewed in a longitudinal direction. The bumper beam 14 is disposed in front of the crash box 12, and both longitudinal ends of the bumper beam 14 are joined to the front end of the crash box 12. In addition, both longitudinal ends of the bumper beam 14 are disposed outboard of the front side frame 10 and the crash box 12 in the left-right direction.

[0013] (Regarding radiator support 16) The radiator support 16 is formed in a generally rectangular frame shape when viewed from the front, and is disposed inside the pair of left and right front side frames 10 in the vehicle width direction and behind the bumper beam 14. Vertical middle portions of both left and right sides of the radiator support 16 are connected to the front side frames 10. A radiator (not shown) is provided inside the radiator support 16 and is supported by the radiator support 16. The rear side of the radiator support is configured as a power unit chamber 24 that houses a power unit (not shown) of the vehicle V, and the power unit chamber 24 is covered from above by a hood 26 provided at the front of the vehicle V.

[0014] (About Absorber 18) The absorber 18 is made of a foamed resin material, i.e., urethane foam or the like. The absorber 18 is formed in a generally elongated shape with the left-right direction as the longitudinal direction, and is disposed adjacent to the front side of the bumper beam 14. The absorber 18 is formed in a generally trapezoidal shape in a cross section seen from the longitudinal direction, and the rear surface of the absorber 18 is fixed to the front surface of the bumper beam 14. In the event of a frontal collision between a pedestrian and the vehicle V, the absorber 18 is compressed and deformed by the pedestrian entering the front end of the vehicle V to the rear together with a bumper cover 20 described later, and absorbs the collision energy on the pedestrian.

[0015] (About Bumper Cover 20) The bumper cover 20 is disposed in front of the absorber 18 and constitutes the front end of the vehicle V. The bumper cover 20 extends in the vehicle width direction and covers the absorber 18 from the front side. A lower end of the bumper cover 20 is connected to a front end of an undercover 22 that constitutes the floor of the vehicle V.

[0016] (About the air guide 30) The air guide 30 is formed in a substantially rectangular frame shape when viewed from the front, corresponding to the radiator support 16, and is disposed in front of the radiator support 16 and behind the bumper beam 14. The air guide 30 is disposed adjacent to the front side of the radiator support 16 and fixed to the radiator support 16. An upper portion of the air guide 30 is positioned above the front side frame 10, and a lower portion of the air guide 30 is positioned below the front side frame 10.

[0017] The inside of the air guide 30 is configured as a guide hole 30A, and the traveling wind that has passed through the bumper cover 20 flows toward the radiator through the guide hole 30A. In other words, the air guide 30 is configured as a guide member that guides the traveling wind to the radiator and the power unit chamber 24.

[0018] (Regarding leg sweep device 40) The leg sweep devices 40 extend in the vertical direction as a whole, and a plurality of leg sweep devices 40 are arranged side by side in the vehicle width direction below the bumper beam 14. That is, the leg sweep devices 40 are arranged between the lower part of the bumper cover 20 and the lower part of the air guide 30. The leg sweep devices 40 include a cylinder 41, a descending member 42, and an airbag 43 as a protective part.

[0019] The cylinder 41 is formed in a generally cylindrical shape with the vertical direction as the axial direction. The upper end of the cylinder 41 is fixed to the lower wall of the bumper beam 14, and the lower end of the cylinder 41 is fixed to the front end of the under-cover 22. In other words, the bumper beam 14 and the under-cover 22 are connected by the cylinder 41. A hole is formed through the front end of the under-cover 22 to open the inside of the cylinder 41 downward.

[0020] The descending member 42 is formed in a columnar shape extending in the vertical direction, and is inserted into the cylinder 41 so as to be vertically movable. When the leg sweep device 40 is in an inoperative state (the state shown in FIG. 1), the upper end of the descending member 42 is engaged with the inner periphery of the cylinder 41 by a ring member or the like (not shown), and the gap between the upper end of the descending member 42 and the inner periphery of the cylinder 41 is sealed. The lower end of the descending member 42 is provided with a bag case portion 42A for accommodating an airbag 43, which will be described later. The bag case portion 42A is formed in the shape of a hollow box, and is accommodated within the lower end of the cylinder 41.

[0021] A gas generator 44 is provided at the upper end of the cylinder 41, and the gas generator 44 is electrically connected to a control unit 45 of the vehicle V. A collision sensor 46 for detecting a frontal collision of the vehicle V is electrically connected to the control unit 45. The collision sensor 46 is composed of a well-known stereo camera, a millimeter wave radar, or the like, and outputs a detection signal to the control unit 45. The control unit 45 is set to activate the gas generator 44 when it detects (including predicts) a frontal collision between a pedestrian and the vehicle V based on information from the collision sensor 46. At this time, the descending member 42 protrudes downward from the undercover 22 due to the pressure of the gas supplied from the gas generator 44 into the cylinder 41, and the bag case portion 42A of the descending member 42 is configured to abut against the ground GR (see FIG. 4). In addition, when the control unit 45 detects a frontal collision of a pedestrian with the vehicle V, it activates the brake system of the vehicle V to stop the vehicle V.

[0022] The airbag 43 is formed into a substantially bag-like shape by sewing one or more base fabrics together, and is stored in a folded state in the bag case portion 42A. One end of a substantially long, flexible tubular duct 55 is connected to the airbag 43, and the other end of the duct 55 is connected to a bladder 54, which will be described later. The airbag 43 is inflated and deployed by compressed air sent from the bladder 54. The airbag 43 in the inflated and deployed state extends in the front-rear direction below the bumper cover 20, and the front part of the airbag 43 protrudes forward from the bumper cover 20 (see the airbag 43 shown by the two-dot chain line in Figs. 2 and 4). A notch (not shown) is formed in the front wall of the bag case portion 42A, and when the airbag 43 is inflated and deployed, the front wall of the bag case portion 42A is configured to tear at the notch due to the inflation pressure of the airbag 43.

[0023] (About the shock absorbing mechanism 50) The shock absorbing mechanism 50 includes a support mechanism 51 and a bladder 54 as a shock absorbing member. The support mechanism 51 includes a movable plate 52 as a movable member and a counterweight 53. The movable plate 52 is formed in a substantially long plate shape with the plate thickness direction being the front-rear direction and the longitudinal direction being the vehicle width direction. In addition, the upper end of the movable plate 52 is inclined toward the rear as it goes upward when viewed from the left-right direction. The movable plate 52 is disposed on the front side of the upper part of the air guide 30, and the lower end of the movable plate 52 is rotatably connected to both left and right sides of the air guide 30 with the vehicle width direction as the axial direction.

[0024] The counterweight 53 is formed in a generally columnar shape extending in the vehicle width direction, and is fixed to the front surface of the upper end portion of the moving plate 52. For example, when the brake system is activated and the vehicle V stops in the event of a frontal collision between a pedestrian and the vehicle V, the moving plate 52 rotates forward around the lower end portion due to the forward inertial force acting on the counterweight 53 and the moving plate 52.

[0025] The bladder 54 is made of an elastic material such as rubber and is formed in a hollow, generally cylindrical bag shape extending in the left-right direction. The bladder 54 is filled with a gas such as air or nitrogen (air in this embodiment), and the bladder 54 is expanded into a cylindrical shape extending in the left-right direction by the air pressure in the bladder 54. The bladder 54 is disposed adjacent to the upper side of the bumper beam 14 and adjacent to the front side of the moving plate 52. That is, the bladder 54 is supported from the rear by the moving plate 52 and from the lower side by the bumper beam 14. The bladder 54 is fixed to the bumper beam 14 at a position not shown in the figure, so that the movement of the bladder 54 in the front-rear direction is restricted. In addition, the upper part of the bumper cover 20 described above is disposed close to the front side of the bladder 54. As a result, in the event of a frontal collision between the pedestrian and the vehicle V, the bumper cover 20, which intrudes into the rear of the front end of the vehicle V together with the pedestrian, is received by the bladder 54, and the impact energy of the pedestrian is absorbed.

[0026] The bladder 54 is connected to the airbag 43 of the leg sweep device 40 by a duct 55, and the duct 55 is provided with a valve 56. As will be described in detail later, in the event of a frontal collision between the vehicle V and a pedestrian, the bladder 54 is compressed and deformed in the front-to-rear direction by the bumper cover 20 and the moving plate 52, and when the pressure in the bladder 54 reaches or exceeds a predetermined value, the valve 56 is operated and the compressed air in the bladder 54 is sent to the airbag 43, causing the airbag 43 to inflate and deploy.

[0027] (Action and effect) Next, the operation and effects of this embodiment will be described.

[0028] In the event of a frontal collision between the pedestrian and the vehicle V, the lower half of the pedestrian collides with the bumper cover 20. Specifically, the thighs and pelvis of the pedestrian hit the upper part of the bumper cover 20, and the bumper cover 20 enters the inside of the front end of the vehicle V rearward and abuts against the bladder 54. In addition, in the event of a frontal collision between the pedestrian and the vehicle V, the brake system is operated by the brake operation of the control unit 45 or the driver, and a braking force acts on the vehicle V. Therefore, a forward inertial force acts on the moving plate 52 including the counterweight 53, and the moving plate 52 rotates (tilts) forward around the lower end due to the inertial force (see FIG. 3). As a result, the moving plate 52 presses the bladder 54 from the rear side, and the air pressure in the bladder 54 increases. Therefore, the bladder 54 with the internal pressure increased receives the thighs and pelvis of the pedestrian from the rear side.

[0029] Furthermore, when the vehicle V collides head-on with a pedestrian, the gas generator 44 of the leg sweep device 40 is actuated by the control unit 45, and gas is supplied from the gas generator 44 into the cylinder 41. As a result, the pressure of the gas supplied into the cylinder 41 causes the descending member 42 to descend relative to the cylinder 41 and protrude downward beyond the under-cover 22, and the bag case portion 42A of the descending member 42 comes into contact with the ground GR (see the descending member 42 shown in FIG. 4).

[0030] Then, when the bumper cover 20 further intrudes rearward, the bladder 54 is further compressed and deformed in the front-rear direction by the bumper cover 20 and the moving plate 52, and the air pressure in the bladder 54 further increases. Then, when the pressure in the bladder 54 reaches or exceeds a predetermined value, the valve 56 of the duct 55 is operated, and compressed air is sent from the bladder 54 to the airbag 43, and the airbag 43 is inflated and deployed forward from the bag case portion 42A (see the airbag 43 shown by the two-dot chain line in FIG. 4). At this time, the front part of the airbag 43 passes under the bumper cover 20 and protrudes forward from the bumper cover 20. As a result, the airbag 43 hits the feet of the pedestrian and pushes them forward. That is, the feet of the pedestrian who is hit by the vehicle V are received and protected by the airbag 43, and are swept forward. As a result, the upper half of the pedestrian's body falls backward, and the pedestrian who falls is received by the hood 26 of the vehicle V.

[0031] As described above, in the vehicle front structure S, the bladder 54 is provided on the rear side of the bumper cover 20 of the vehicle V, and is supported from the rear side by the moving plate 52 of the support mechanism 51. The moving plate 52 is movably connected to the air guide 30. Then, in the event of a frontal collision between the vehicle V and a pedestrian (collision object), the brake system of the vehicle V is activated by the brake operation of the control unit 45 or the driver, and the vehicle V is braked. At this time, the moving plate 52 moves forward by inertial force and presses the bladder 54. Therefore, the bladder 54 is compressed and deformed, and the air pressure in the bladder 54 increases. As a result, the bladder 54 with the increased internal pressure can receive the pedestrian who enters the front end of the vehicle V. That is, the pedestrian can be received during a frontal collision while increasing the internal pressure of the bladder 54 that is already filled with gas. As a result, the collision energy of the pedestrian can be absorbed without using a gas generating device for inflating the bladder 54. Therefore, it is possible to improve the protection performance for pedestrians (collision objects) in the event of a collision while reducing costs.

[0032] The support mechanism 51 includes a movable plate 52 movably connected to the air guide 30, and a counterweight 53 provided on the movable plate 52. As a result, the counterweight 53, which moves forward due to inertial force when the vehicle V is braked, can satisfactorily move the movable plate 52 forward.

[0033] The moving plate 52 is formed in a plate shape with the plate thickness direction being in the vehicle front-rear direction. The lower end of the moving plate 52 is rotatably connected to the air guide 30 with the vehicle width direction as the axial direction, and the counterweight 53 is provided at the upper end of the moving plate 52. This allows the moving plate 52 to be moved (rotated) forward more satisfactorily when the vehicle V is braked. That is, when the vehicle V is braked, pitching occurs in the vehicle V, and the posture of the vehicle V is in a forward tilted posture. This allows the direction of rotational motion acting on the vehicle V when pitching occurs to coincide with the direction of rotation of the moving plate 52 when the vehicle V is braked. Therefore, the moving plate 52 can be moved (rotated) forward more satisfactorily when the vehicle V is braked.

[0034] Furthermore, when the bumper cover 20 penetrates further rearward into the front end of the vehicle V from the early stage of a frontal collision between the pedestrian and the vehicle V, the bladder 54 is compressed and deformed in the front-rear direction by the bumper cover 20 and the moving plate 52. That is, the amount of compressive deformation of the bladder 54 increases, and the pressure in the bladder 54 rises further compared to the early stage of a frontal collision. Then, when the pressure in the bladder 54 reaches a predetermined value or more, compressed air is sent from the bladder 54 to the airbag 43 of the leg sweep device 40, and the airbag 43 is inflated and deployed forward by the compressed air. This makes it possible to utilize the compressed air in the bladder 54 to inflate and deploy the airbag 43, and to protect the feet of the pedestrian and sweep the feet of the pedestrian. That is, the compressed air in the bladder 54 can be utilized as a driving source for inflating and deploying the airbag 43. This contributes to reducing the cost of the leg sweep device 40.

[0035] In this embodiment, the lower end of the moving plate 52 of the shock absorbing mechanism 50 is rotatably connected to the air guide 30, but the method of connecting the moving plate 52 to the air guide 30 is not limited to this. For example, the air guide 30 may be provided with a rail portion extending in the front-rear direction, and the moving plate 52 may be movably connected to the rail portion. In this case, the counterweight 53 may be provided in the middle of the moving plate 52 in the up-down direction.

[0036] In addition, in the leg sweep device 40 of this embodiment, the airbag 43 is configured to inflate and deploy after the descending member 42 descends, but the configuration of the leg sweep device 40 is not limited to this. For example, the leg sweep device 40 may be configured such that the descending member 42 is fixed to the under-cover 22 and the airbag 43 is inflated and deployed, causing the lower end of the bumper cover 20 to break and protrude forward together with the airbag 43. In this case, the cylinder 41 and the gas generator 44 can be omitted in the leg sweep device 40, which contributes to reducing the cost of the leg sweep device 40.

[0037] In addition, in the leg sweep device 40 of this embodiment, the inflated and deployed airbag 43 is configured to sweep the legs of a pedestrian, but the configuration for sweeping the legs of a pedestrian is not limited to this. For example, a configuration may be adopted in which an extension mechanism that can be extended forward is provided at the lower end of the descending member 42, and the extension mechanism is operated by compressed air sent from the bladder 54 to sweep the legs of a pedestrian.

[0038] In addition, in this embodiment, the compressed air in the bladder 54 is used to inflate and deploy the airbag 43 of the leg sweep device 40, but the compressed air in the bladder 54 may also be used for other protective devices. For example, it may be used to inflate and deploy all or a part of the hood airbag that inflates and deploys around the rear end of the hood 26 that is lifted upward in the event of a frontal collision between a pedestrian and the vehicle V. [Explanation of symbols]

[0039] 20 Bumper Cover 30 Air guide (body component) 40 Leg sweep device (protective device) 43 Airbag (protective part) 51 Support mechanism 52 Moving plate (moving part) 53 Counterweight 54 Bladder (shock absorbing material) S Vehicle front structure V Vehicle

Claims

1. A bumper cover provided at a front end of the vehicle and extending in a vehicle width direction; a hollow shock absorbing member provided on a vehicle rear side of the bumper cover and filled with gas; a support mechanism that supports the shock absorbing member from a rear side of the vehicle, is movably connected to a vehicle body member, and compresses the shock absorbing member by moving toward the front side of the vehicle due to inertia force; A vehicle front structure comprising:

2. The support mechanism includes: A moving member movably connected to the vehicle body member; A counterweight provided on the moving member; The vehicle front structure according to claim 1 , comprising:

3. The moving member is formed in a plate shape with a plate thickness direction in the vehicle front-rear direction, and a lower end of the moving member is rotatably connected to the vehicle body member with an axial direction in the vehicle width direction, 3. The vehicle front structure according to claim 2, wherein the counterweight is provided on an upper end of the movable member.

4. The vehicle front structure according to any one of claims 1 to 3, further comprising a protection device that is activated when an impact body collides with the bumper cover and that protrudes further forward than the bumper cover to protect the impact body.

5. the protection device is connected to the impact absorbing member and has a protection portion that protrudes toward a vehicle front side of the bumper cover when activated, 5. The vehicle front structure described in claim 4, wherein when an impact body collides with the bumper cover, the impact absorbing member is compressed and deformed in the fore-and-aft direction of the vehicle by the bumper cover and the support mechanism, so that compressed gas inside the impact absorbing member is sent from the impact absorbing member to the protection device, and the protection section is activated by the gas.

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