JP6077402B2 - Body front structure - Google Patents

Description

  The present invention relates to a vehicle body front structure of a vehicle such as an automobile, and more particularly to a vehicle body that can obtain appropriate vehicle body characteristics according to a collision mode.

The vehicle body front structure of a vehicle such as an automobile is required to ensure various characteristics required for ensuring the safety of passengers with respect to various collision modes.
Typical collision modes include, for example, a full lap collision and an offset collision in which a collision object collides with the host vehicle from the front, an oblique collision in which a collision object collides from an oblique front, and in an offset collision, The size of the lap rate with the vehicle is also a problem.

As a conventional technique related to changing the characteristics of the vehicle body in accordance with the change in the collision mode, for example, in Patent Document 1, a lateral force generator is provided inside a hollow member such as a vehicle body frame, and a constrained state between opposing surfaces Is described in which an appropriate reaction force load according to the collision mode can be obtained by changing the value according to the collision mode.
Moreover, as a prior art regarding the detection of a collision form, for example, Patent Document 2 detects a collision form using an environment recognition device having a radar, a camera, and the like, and an automatic deceleration device, an occupant protection device, etc. It is described that control is performed.

JP 2005-035519 A JP 2005-28992 A

In recent years, the lap rate is particularly small among offset collisions, and there has been a demand for improved performance with respect to collision forms that do not wrap with the front side frame (main frame).
As a response to such an offset collision of the small overlap, the front end is connected to the vicinity of the front end of the front side frame, and the rear end is on the upper side with respect to the front side frame and on the outer side in the vehicle width direction with an A pillar or the like. It has been proposed to provide a front upper frame that is inclined with respect to the front side frame so as to be connected.
By providing such a front upper frame and strengthening the front part of the vehicle body, it is possible to change the behavior of the vehicle at the time of a collision and convert the energy resulting from the collision into kinetic energy, thereby suppressing vehicle body deformation.

However, if the vehicle body structure around the front upper frame is strengthened, there is a concern that the load and acceleration will rise suddenly at the time of a full lap collision, and the damaging effect on passengers in the cabin will deteriorate.
In view of the above-described problems, an object of the present invention is to provide a vehicle body front structure that can obtain appropriate vehicle body characteristics according to a collision mode.

The present invention solves the above-described problems by the following means.
The invention according to claim 1 is a pair of front side frames that protrude from the front end of the cabin toward the front side of the vehicle and are spaced apart from each other on the left and right sides, and the front end is connected to a region near the front end of the front side frame. And a pair of left and right front upper frames whose rear end portions are connected to the cabin front end portion above the front side frame and outside in the vehicle width direction, an intermediate portion between the left and right front side frames, and the front upper portion. A pair of left and right connecting members that respectively connect the middle portion of the frame, a connection release mechanism that releases the connection of the connecting members, a collision of the vehicle or a sign of the collision is detected, and the collision form is determined, and the collision form is determined. Accordingly, the vehicle body front structure includes a connection release control unit that controls the connection release mechanism.
According to this, by controlling the connection or disconnection of the connecting member according to the collision mode, it is possible to obtain an appropriate vehicle body characteristic corresponding to each collision mode and improve the collision safety of the vehicle.
Further, it is possible to reduce the weight necessary for the countermeasure against the collision and to prevent the front overhang of the vehicle from becoming excessively long.

According to a second aspect of the present invention, the connection release control means causes the connection release mechanism to release the connection of the connection member at the time of a full lap collision of the vehicle, and to the connection release mechanism at the time of an offset collision in which the lap rate is a predetermined value or less. The vehicle body front part structure according to claim 1, wherein the connection of the connection members is maintained.
According to this, by releasing the connection of the connecting member at the time of a full wrap collision, it becomes possible to generate a load with a phase difference (with a time difference) between the front side frame and the front upper frame, and a suddenly large It is possible to prevent the occurrence of acceleration and suppress injury to passengers in the passenger compartment.
On the other hand, at the time of an offset collision, by maintaining the connection of the connecting member, the deformation of the vehicle body can be suppressed, and the behavior of the vehicle body escaping from the collision object in the vehicle width direction can be generated to convert the collision energy into kinetic energy. it can.

According to a third aspect of the present invention, the connection release control means causes the connection release mechanism to release the connection of at least the collision-side connection member when the vehicle collides with the collision object from an oblique direction. The vehicle body front part structure according to claim 2, wherein the vehicle body front part structure is a vehicle body front structure.
According to this, it is possible to stabilize the behavior of the occupant in the passenger compartment and reduce the harmfulness by generating a behavior that shifts with respect to the collision object while deforming the vehicle body and sticking to the collision object at the time of an oblique collision. it can.

The invention according to claim 4 is characterized in that the connection release control means detects a sign of a collision using an environment recognition means for recognizing an environment in front of the host vehicle and discriminates the collision form. The vehicle body front part structure according to any one of claims 1 to 3.
According to this, by detecting the precursor of the collision using the environment recognition means, it is possible to control the release mechanism by the pre-crash control prior to the collision, and to set the desired vehicle body characteristics before the collision. Can do.
Further, by determining the collision mode using the environment recognition means, the accuracy of determining the collision mode can be improved and the above-described effects can be obtained more reliably.

The invention according to claim 5 is characterized in that the environment recognizing means includes a stereo camera that images the front of the host vehicle and an image processing means that performs stereo image processing on an output image of the stereo camera. It is a vehicle body front structure.
According to this, the above-described effects can be appropriately obtained with a relatively simple and inexpensive apparatus configuration.

  According to this, it is possible to provide a vehicle body front structure in which appropriate vehicle body characteristics can be obtained according to the collision mode.

It is the top view which looked at the Example of the vehicle body front part structure to which this invention is applied from upper direction. It is the side view which looked at the vehicle body front part structure of the Example from the side. It is typical sectional drawing of the III-III part of FIG. It is a block diagram which shows the structure of the control system of the connection cancellation | release mechanism in the vehicle body front part structure of an Example. It is a flowchart which shows control of the connection release mechanism in the vehicle body front part structure of an Example. It is a top view which shows the state at the time of the full lap collision in the vehicle body front part structure of an Example. It is a graph which shows typically an example of the time history of the load at the time of a full lap collision in the body front part structure of an example. It is a top view which shows the state at the time of the offset collision in the vehicle body front part structure of an Example. It is a top view which shows the state at the time of the diagonal collision in the vehicle body front part structure of an Example.

  SUMMARY OF THE INVENTION The present invention provides a vehicle body front structure capable of obtaining appropriate vehicle body characteristics according to a collision mode, and includes a front end portion of a front side frame, and a cabin front portion on the outer side in the vehicle width direction and above the front side frame. This is solved by providing a front upper frame for connecting the intermediate members of the front upper frame and the intermediate member of the front side frame by switching the connection or release of the connection member according to the collision type of the vehicle.

Embodiments of a vehicle body front structure to which the present invention is applied will be described below.
The vehicle body front structure according to the embodiment is applied to an automobile such as a passenger car configured by housing a power unit such as a horizontally opposed engine mounted vertically in an engine room in the vehicle front part.
FIG. 1 is a plan view of the front body structure of the embodiment as viewed from above.
FIG. 2 is a side view of the vehicle body front part structure of the embodiment as viewed from the side (II-II part arrow view of FIG. 1).

  The vehicle body front structure 1 includes a front portion of a cabin 10, a front side frame 20, a strut accommodating portion 30, a bumper beam 40, a radiator panel 50, a front upper frame 60, a connection member 70, a connection release mechanism 80, and the like. ing.

The cabin 10 is a portion that is provided at a central portion in the front-rear direction of the vehicle body and forms a space for accommodating a passenger or the like.
The cabin 10 includes a toe board (bulk head) 11, an A pillar 12, a side sill 13, and the like.
The toe board 11 is a partition that is provided at the front end of the cabin 10 and divides the vehicle compartment and the engine room.
The upper end portion of the toe board 11 is disposed along the lower end portion of a front window glass (not shown) and the rear end portion of a hood (bonnet) (not shown).
The lower end portion of the toe board 11 is formed continuously with the front end portion of the floor panel constituting the passenger compartment floor surface portion.

The A pillar 12 is a columnar part that is provided at the front end of the cabin 10 and extends in the vertical direction and has a closed cross-sectional shape.
The upper portion of the A pillar 12 is disposed so as to protrude from the side end portion at the upper portion of the toe board 11 to the oblique rear side on the upper side.
The upper portion of the A pillar 12 is disposed along the side end portion of the front window glass and the front end portion of the front door glass (not shown).
A lower portion of the A pillar 12 extends in the vertical direction along the side end portion of the toe board 11.
The side sill 13 is a structural member that is formed to protrude from the lower end portion of the A pillar 12 toward the vehicle rear side and has a closed cross-sectional shape.
The side sill 13 is disposed along the side edge of the floor panel.

The front side frame 20 is a structural member formed to protrude forward from the lower part of the toe board 11 of the cabin 10.
One front side frame 20 is provided on each of the left and right sides of the engine room so as to be separated from each other in the vehicle width direction.
The front side frame 20 has a closed cross-sectional shape that is rectangular when viewed from the front of the vehicle.
An engine cross member on which the engine E is placed via an elastic mount is coupled to an intermediate portion of the front side frame 20 in the front-rear direction.
The engine cross member is provided between the lower portions of the left and right front side frames 20.
A flange 21 used for mounting the bumper beam 40 is provided at the front end of the front side frame 20.

The strut accommodating portion 30 is a portion that accommodates the upper portion of the strut S that constitutes a part of the McPherson strut type front suspension of the vehicle.
The strut S is a unit composed of a shock absorber and a coil spring.
A housing H provided with a hub bearing for rotatably supporting the front wheel is fixed to the lower end portion of the strut S.
The strut accommodating portion 30 is formed in the vicinity of the rear end portion of the front side frame 20 so as to protrude outward and upward in the vehicle width direction from the front side frame 20.
The rear portion of the strut accommodating portion 30 is fixed to the toe board 11.
The strut accommodating portion 30 is formed in a container shape opened downward, and the upper portion of the strut S is accommodated therein.
A strut upper mount 31 is provided at the upper end portion of the strut accommodating portion 30, and the upper end portion of the strut S is rotatably attached thereto.

The bumper beam 40 is a member that connects the front end portions of the front side frame 20.
The bumper beam 40 receives a load from a bumper face (not shown) at the time of a frontal collision of the vehicle and transmits it to the front side frame 20.
The bumper beam 40 is formed in a beam shape having a closed cross-sectional shape, for example, by joining a plurality of panels formed by press-molding steel plates or by extruding aluminum alloy.
As shown in FIG. 1, the bumper beam 40 is formed so as to be curved so that the front side of the vehicle is convex when viewed from above in accordance with the formation of the bumper face.
In the vicinity of both end portions of the bumper beam 40 in the vehicle width direction, stays 41 are provided so as to protrude rearward. A flange 42 is provided at the rear end of the stay 41.
The bumper beam 40 is attached to the vehicle body by fastening a flange 42 to the flange 21 of the front side frame 20.
A portion of the stay 41 on the outer side in the vehicle width direction is formed as a slope inclined with respect to the vehicle front-rear direction so as to protrude outward in the vehicle width direction on the vehicle rear side.

The radiator panel 50 is a structural member provided between the front end portions of the left and right front side frames 20 behind the bumper beam 40 and in front of the engine E.
The radiator panel 50 is formed in a substantially rectangular frame shape when viewed from the vehicle front side.
The radiator panel 50 is provided with a heat exchanger H such as a radiator core and a condenser of an air conditioner, an electric fan, and the like.

The front upper frame 60 is a beam-like member that connects the front end portion of the front side frame 20 and the intermediate portion of the A pillar 12.
The front upper frame 60 has a substantially rectangular closed cross-sectional shape.
The rear portion 61 of the front upper frame 60 is formed in the vicinity of the upper end portion of the toe board 11 so as to protrude from the A pillar 12 to the vehicle front side.
Gusset plate-shaped stiffening members 61 a and 61 b are provided at the joint between the A pillar 12 and the rear portion 61.
An end of the strut upper mount 31 on the outer side in the vehicle width direction is joined to the inner side of the rear portion 61 in the vehicle width direction.
The rear portion 61 is preferably disposed through the side of the strut upper mount 31 so as to avoid the front end portion of the strut upper mount 31 in order to efficiently transmit the compressive load in the front-rear direction to the cabin 10 at the time of collision.

The front part 62 of the front upper frame 60 is formed continuously from the front end part of the rear part 61.
The front end portion of the front portion 62 is fixed to the outer side in the vehicle width direction at the front end portion of the front side frame 20.
The rear end portion of the front portion 62 is connected to the front end portion of the front portion 62.
The front portion 62 is disposed to be inclined with respect to the vehicle front-rear direction so that the rear end portion is on the outer side and the upper side in the vehicle width direction with respect to the front end portion.
For this reason, the front upper frame 60 is formed to bend at the connection portion between the front portion 62 and the rear portion 61.

The connecting member 70 is a beam-like structural member that connects the intermediate portion of the front portion 62 of the front upper frame 60 and the intermediate portion of the front side frame 20.
The connection portion of the front side frame 20 with the connection member 70 is preferably a portion having high rigidity and strength against a load received from the connection member 70. For example, an engine cross member and a suspension for connecting the left and right front side frames 20 It may be in the vicinity of a place where a structural member such as a cross member is provided.
The connecting member 70 is formed in a rectangular pipe shape having a rectangular closed cross section extending substantially linearly, and the end on the front side frame 20 side is below the vehicle rear side and the lower side with respect to the end on the front upper frame 60 side. It is arranged to be inclined with respect to the front-rear direction, the vehicle width direction, and the vertical direction so as to be on the inner side in the vehicle width direction.
The end portion of the connecting member 70 on the front upper frame 60 side is fixed to the front portion 62 of the front upper frame 60 by, for example, welding or mechanical fastening means such as a bolt.

In addition, a connection release mechanism 80 is provided at an end of the connection member 70 on the front side frame 20 side so that connection or release of the connection member 70 and the front side frame 20 can be switched by an actuator.
3 is a schematic cross-sectional view taken along the line III-III in FIG.
A flat plate-like fixed surface portion 71 arranged substantially horizontally is formed at the end of the connecting member 70 on the front side frame 20 side.
The fixed surface portion 71 is fixed to the main body portion of the connecting member 70 and is in contact with the upper surface portion of the front side frame 20.
Concentric openings arranged opposite to each other are formed in the fixed surface portion 71 and the upper surface portion of the front side frame 20.

The disengagement mechanism 80 includes a connecting pin 81 and an actuator 82 (subscripts L and R are attached to the actuators 82 of the left and right disengagement devices 80 in FIG. 4 described later).
The connection pin 81 is movable between a position where it is inserted into the opening of the fixed surface portion 71 and the opening of the upper surface portion of the front side frame 20 and a connection release position pulled out from at least one of the openings. Yes.
When the connecting pin 81 is in the connecting position, the connecting member 70 can transmit the axial force of the connecting member 70 to and from the front side frame 20 via the connecting pin 81.
The actuator 82 is an electric actuator having, for example, a solenoid or the like that drives the connection pin 81 between the above-described connection position and connection release position.
The actuator 82 is controlled by an actuator control ECU 130, which will be described later, and holds the connecting pin 81 in the connecting position during normal use of the vehicle (a state in which no collision or a sign of the collision is detected).

Next, the configuration of a control system that controls the above-described connection release mechanism 80 will be described.
FIG. 4 is a block diagram illustrating a configuration of a control system of the connection release mechanism in the vehicle body front structure according to the embodiment.
The control system includes an environment recognition device 110, a collision determination ECU 120, and an actuator control ECU 130. Further, an airbag ECU 200 is connected to the collision determination ECU 120.

The environment recognition apparatus 110 includes a stereo camera including a left camera 111 and a right camera 112, and uses a known stereo image processing technique, such as the lane shape in front of the host vehicle, the type of an object such as another vehicle, an obstacle, and the like. Is detected.
The left camera 111 and the right camera 112 are, for example, image pickup means that are arranged in the left and right direction at the upper end of the windshield of the vehicle (near the room mirror).
The environment recognition device 110 recognizes obstacles and the like based on images captured by the left camera 111 and the right camera 112, and calculates the distance from the host vehicle based on the principle of triangulation using the parallax of each camera. Perform stereo image processing.

The left camera 111 and the right camera 112 output a pair of captured images as stereo images at any time by imaging the front of the host vehicle in time series at a predetermined interval.
The environment recognition apparatus 110 performs stereo image processing for each stereo image and generates a distance image.
A distance image is defined as a set of distance values (parallax) associated with a position on the image plane. Here, the amount of horizontal displacement of the correlated pixel blocks in the left and right images is parallax.
The environment recognition apparatus 110 calculates the distance from the subject vehicle of the subject of the pixel block based on the parallax.

The environment recognition device 110 detects adjacent pixel groups having substantially the same distance value as an object, and based on the height direction and width direction size and outline shape, a pedestrian, an oncoming vehicle, a building And the like, and the terrain adjacent to the lane.
In this way, the environment recognition apparatus 110 is configured so that the shape and size of an object that may collide with another vehicle or an obstacle such as an obstacle included in the imaging range of the left camera 111 and the right camera 112, and the own vehicle. The relative position, relative speed, etc. can be recognized.

The collision determination ECU 120 determines the possibility of an object colliding with the host vehicle based on the recognition result of other vehicles and obstacles by the environment recognition device 110, and determines the collision mode when the possibility of collision is high. To do.
Here, as the collision mode, there are a frontal collision in which the collision target collides substantially along the front-rear direction of the host vehicle and an oblique collision in which the collision target collides from the diagonally front side with respect to the host vehicle.
Further, in the frontal collision, the ratio (lap ratio) of the collision area with the collision object with respect to the vehicle width of the host vehicle is relatively large, and a full lap collision that receives a collision at the front end portions of the left and right front side frames 20, There is an offset collision in which the lap rate is small with respect to a full lap collision and the collision is received only on one front side frame 20 or the collision is received only on the outer side of the front side frame 20 in the vehicle width direction.
The collision determination ECU 120 sets an object recognized as having a high possibility of a collision based on the relative position and relative speed with respect to the host vehicle among other objects recognized by the environment recognition device 110 as a collision target. The collision mode is determined using the shape, size, relative position, and relative speed.

The actuator control ECU 130 controls the actuators 82 (82 </ b> L, 92 </ b> R) of the left and right connection release mechanisms 80 based on the determination result of the collision possibility and the collision form by the collision determination ECU 120.
The airbag ECU 200 controls the deployment and inflation of an airbag provided in the vehicle interior.
For example, when the airbag ECU 200 detects a vehicle collision by an acceleration sensor or the like provided at the front end of the vehicle, the airbag ECU 200 deploys and expands the airbag by operating a gas generator that supplies a gas for deployment and inflation to the airbag.

Hereinafter, the control of the connection release mechanism of the first embodiment will be described.
FIG. 5 is a flowchart showing the control of the connection release mechanism in the vehicle body front part structure of the embodiment.
Hereinafter, the steps will be described step by step.

<Step S01: Recognition of environment outside the vehicle>
The environment recognition device 110 recognizes a relative position, a relative speed, a shape, a size, and the like of the other vehicle in front of the own vehicle, a building, and the like, and provides a recognition result to the collision determination ECU 120.
Thereafter, the process proceeds to step S02.

<Step S02: Determination of collision possibility>
The collision determination ECU 120 determines whether or not there is a possibility that the own vehicle, a building, or the like collides with the own vehicle based on the recognition result of the environment outside the vehicle provided from the environment recognition device 110.
The determination of the possibility of collision is performed, for example, on the assumption that the possibility of collision increases as the object exists in a direction closer to the traveling direction of the host vehicle, the relative distance is closer, and the relative speed is higher.
If the possibility of collision is greater than or equal to a predetermined value, the process proceeds to step S03, and in other cases, a series of processing ends (returns).

<Step S03: Collision form detection>
The collision determination ECU 120 is based on the recognition result of the environment outside the vehicle provided from the environment recognition device 110, and objects such as other vehicles, buildings, etc. (hereinafter referred to as collision targets) for which the possibility of collision is determined to be greater than or equal to a predetermined value in step S02. The collision mode of the vehicle with the host vehicle is determined.
Specifically, it is determined whether the host vehicle is a frontal collision substantially facing the collision object or the host vehicle is an oblique collision that obliquely collides with the collision object.
In the case of a frontal collision, the lap rate between the host vehicle and the collision object is calculated, and the lap rate is equal to or greater than a predetermined value (the front end portions of the left and right front side frames 20 are both included in the collision region). In some cases, it is determined that a full lap collision occurs, and when the lap rate is less than a predetermined value, it is determined that an offset collision occurs.
Thereafter, the process proceeds to step S04.

<Step S04: Judgment of oblique collision>
The collision determination ECU 120 proceeds to step S05 if it is determined in step S03 that it is a diagonal collision, and proceeds to step S07 assuming that it is a frontal collision in other cases.

<Step S05: Collision side connection member connection release>
The actuator control ECU 130 drives the actuator 82 of the connection release mechanism 80 on the side that collides with the collision object, and releases the connection between the connection member 70 and the front side frame 20.
Thereafter, the process proceeds to step S06.

<Step S06: Improvement of sensitivity of airbag sensor>
Airbag ECU 200 improves the sensitivity of an acceleration sensor for collision detection used for airbag deployment and inflation control.
Thereafter, the series of processing is terminated (returned).

<Step S07: full lap collision determination>
The collision determination ECU 120 proceeds to step S10 if it is determined in step S03 that it is a full lap collision, and proceeds to step S08 if it is determined that it is an offset collision.

<Step S08: Left and right connecting member connection maintenance>
The actuator control ECU 130 maintains the connection between the left and right connecting members 70 and the front side frame 20 without driving both the actuators 82 of the left and right connection releasing mechanisms 80.
Thereafter, the process proceeds to step S09.

<Step S09: Airbag Operation Delay>
The airbag ECU 200 performs the deployment and inflation of the airbag by delaying the time from the detection of the collision until the start of the deployment and inflation of the airbag with respect to the case of the full-wrap collision.
Thereafter, the series of processing is terminated (returned).

<Step S10: Left and right connecting member connection release>
The actuator control ECU 130 drives the actuator 82 of the left / right connection release mechanism 80 to release the connection between the connection member 70 and the front side frame 20.
Then, it progresses to step S11.

<Step S11: Airbag sensor sensitivity improvement>
Airbag ECU 200 improves the sensitivity of an acceleration sensor for collision detection used for airbag deployment and inflation control.
Thereafter, the series of processing is terminated (returned).

Hereinafter, the effect of the present embodiment will be described.
FIG. 6 is a plan view showing a state at the time of a full lap collision in the vehicle body front structure of the embodiment.
6, 8, and 9, the transmitted load is schematically illustrated by white arrows.
When a full wrap collision of the barrier B imitating the collision object is detected, the actuator control unit 130 drives the actuators 82 of the left and right connection release mechanisms 80 by the pre-crash control before the collision, The connection of the left and right connecting portions (the portions indicated by broken line circles in FIG. 6) with the connecting member 70 is released.
Thus, after the collision, the front side frame 20 and the front upper frame 60 can be deformed separately to absorb energy.

FIG. 7 is a graph schematically illustrating an example of a load time history at the time of a full lap collision in the vehicle body front structure according to the embodiment.
In FIG. 7, the horizontal axis represents time, and the vertical axis represents load.
In FIG. 7, the load generated by deformation of the front upper frame 60 is indicated by a broken line, and the load generated by deformation of a portion other than the front upper frame 60 (mainly the front side frame 20) is indicated by a solid line.

  As shown in FIG. 7, in this embodiment, when the full lap collision occurs, the front side frame 20 and the front upper frame 60 are disconnected, and these are separately deformed with a phase difference. It becomes possible to disperse, and it is possible to prevent a large acceleration from being generated suddenly and to suppress the harmfulness to the occupant.

FIG. 8 is a plan view showing a state at the time of an offset collision in the vehicle body front part structure of the embodiment.
In the case of an offset collision, by not releasing the connection between the front side frame 20 and the front upper frame 60, load transmission is performed between the front side frame 20 and the front upper frame 60, and the front part of the vehicle body is relatively strong. It becomes.
As a result, the vehicle body deformation can be suppressed and a living space for the occupant can be secured.
Further, in the case of a small overlap offset collision in which the collision object (in this case, the barrier B) does not wrap to the front side frame 20, an input is made to the outer surface in the vehicle width direction of the front portion 62 of the front upper frame 60. The transmitted load is transmitted to the opposite front side frame 20 through the connecting member 70, the collision side front frame 20, the engine E, etc., and as a result, the behavior of the vehicle body in the direction of escaping from the collision object. Can be generated. By generating such a behavior, it is possible to convert collision energy into kinetic energy, suppress vehicle body deformation, and improve collision safety.

FIG. 9 is a plan view showing a state at the time of an oblique collision in the vehicle body front structure of the embodiment.
In the case of the oblique collision, the actuator control unit 130 drives the actuator 82 of the coupling release mechanism 80 on the collision side (left side in the case of FIG. 9) by the pre-crash control, and the front side frame 20 and the coupling member. The connection of the left and right connection portions (locations indicated by broken line circles in FIG. 9) with 70 is released.
As a result, the vehicle body is deformed at the time of an oblique collision to generate a behavior that shifts with respect to the collision target object while sticking to the collision target object (barrier B), and suppresses the behavior of the vehicle body bouncing, thereby suppressing the behavior of the occupant in the cabin 10. Can be stabilized to reduce the harm.

  Further, in the embodiment, by performing the above-described collision mode discrimination by the environment recognition device 110 having a stereo camera, the collision mode discrimination accuracy is improved by a relatively simple and inexpensive device configuration, and the above-described effects are further improved. You can definitely get it.

(Modification)
The present invention is not limited to the embodiments described above, and various modifications and changes are possible, and these are also within the technical scope of the present invention.
(1) The shape, structure, material, manufacturing method, arrangement, number, and the like of each component constituting the vehicle body front structure are not limited to the above-described embodiments, and can be changed as appropriate.
(2) In the embodiment, a stereo camera and a stereo image processing device are used as the environment recognition device. However, the present invention is not limited to this, and a radar such as a laser radar or a millimeter wave radar may be used. Further, such a radar and a camera may be used in combination.
(3) In the embodiment, the connection release mechanism is controlled by pre-crash control using the environment recognition device. For example, when a collision is detected by an acceleration sensor provided at the front end of the vehicle body, the connection release mechanism is controlled. You may make it drive. In this case, it is desirable to use, for example, an explosive type actuator from the viewpoint of responsiveness.
In this case, the lap rate may be estimated based on output waveforms of a plurality of acceleration sensors arranged in the vehicle width direction.
(4) In the embodiment, the connection release mechanism releases the connection between the connection member and the front side frame. However, the connection release mechanism is not limited to this, and the connection between the connection member and the front upper frame is released. You may make it isolate | separate the middle of.
Also, the operation and configuration of the connection release mechanism are not particularly limited.

DESCRIPTION OF SYMBOLS 1 Vehicle body front structure E Engine 10 Cabin 11 Toe board 12 A pillar 13 Side sill 20 Front side frame 21 Flange 30 Strut accommodating part 31 Strut upper mount S Strut H housing 40 Bumper beam 41 Stay 42 Flange 50 Radiator panel 60 Front upper frame 61 Rear part 62 Front part 70 Connection member 71 Fixed surface part 80 Connection release mechanism 81 Connection pin 82 (82L, 82R) Actuator 110 Environment recognition device 111 Left camera 112 Right camera 120 Collision judgment ECU 130 Actuator control ECU
200 Airbag ECU B Barrier

Claims (5)

A pair of front side frames that are formed to protrude from the front end of the cabin toward the front side of the vehicle and are arranged apart from each other left and right;
A pair of left and right front upper frames having a front end connected to a region near the front end of the front side frame and a rear end connected to the cabin front end on the upper side and the vehicle width direction outside of the front side frame When,
A pair of left and right connecting members that respectively connect the middle part of the left and right front side frames and the middle part of the front upper frame;
A connection release mechanism for releasing connection of the connection member;
A vehicle body front structure, comprising: a connection release control unit that detects a vehicle collision or a sign of a collision, determines a collision form, and controls the connection release mechanism in accordance with the collision form. The connection release control means causes the connection release mechanism to release the connection of the connection member at the time of a full lap collision of the vehicle, and causes the connection release mechanism to maintain the connection of the connection member at the time of an offset collision in which a lap rate is a predetermined value or less. The vehicle body front part structure according to claim 1, wherein: The connection release control means causes the connection release mechanism to release the connection of at least the connection member on the collision side when the vehicle collides with an object to be collided from an oblique direction. Car body front structure. 4. The method according to claim 1, wherein the disengagement control unit detects a precursor of a collision using an environment recognition unit that recognizes an environment ahead of the host vehicle, and determines the collision mode. 5. The vehicle body front structure according to item 1. The vehicle body front structure according to claim 4, wherein the environment recognition unit includes a stereo camera that captures an image in front of the host vehicle and an image processing unit that performs stereo image processing on an output image of the stereo camera.

Images