JP2010089775A - Bumper stay - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bumper stay capable of obtaining superior shock absorbing effect. <P>SOLUTION: The bumper stay placed between a vehicle body member and a reinforcement has an R-side contact portion 2 in contact with a rear end side surface of the reinforcement, an S-side contact portion 3 in contact with the front end side surface of the vehicle body member, and a connection part 4 for connecting both, wherein the reinforcement side is a front end, and the vehicle member side is a rear end. The R-side contact portion 2 has a first R-side contact portion 21 provided in both ends in the width-direction of the bumper stay 1, and disposed outside the vehicle body in the width-direction (outside) when mounted, and a second R-side contact portion 22 disposed inside the vehicle body in the width-direction (inside) when mounted. The S-side contact portion 3 has a first S-side contact portion disposed outside and a second S-side contact portion disposed inside corresponding to two end side surfaces of the vehicle member respectively. The connection part 4 is composed of four ribs 41 extending almost in longitudinal direction of the vehicle and a rib connecting plate 42 for connecting them at the front end. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a bumper stay for a vehicle.

2. Description of the Related Art Conventionally, bumper devices are provided on the front and rear surfaces of a vehicle body such as an automobile in order to absorb the impact at the time of collision and reduce the impact energy transmitted to the vehicle body.
A reinforcement as a strength reinforcing member is provided inside the bumper device so as to extend in the width direction of the vehicle. The reinforcement is attached to the vehicle body via a bumper stay fixed to the vehicle body member of the vehicle.

  The above bumper device relieves the impact force on the vehicle body and the occupant by absorbing the impact energy when the bumper stay and the reinforcement are plastically deformed when an impact force exceeding a predetermined level is applied to the bumper device. And has the ability to protect.

The bumper stay generally includes a reinforcement side contact portion facing the reinforcement side, a vehicle body member side contact portion facing the vehicle body member side, the reinforcement side contact portion, and the vehicle body member side contact portion. And a plurality of ribs for connecting the two.
And the various techniques regarding the structure of a bumper stay aiming at improving the impact absorption effect are reported (patent documents 1-3).

JP 2003-112857 A JP 2003-31399 A JP 2006-27501 A

  In the bumper stay as described above, it has been found that the shape change greatly affects the shock absorbing effect through the repeated improvement processes so far. Therefore, there is still room for further improving the impact absorbing effect by further improving the shape. In addition, from the automobile industry using bumper stays, it is desired to improve the impact absorbing effect of the bumper stays.

  The present invention has been made in view of such conventional demands, and an object of the present invention is to provide a bumper stay that can obtain an even better impact absorbing effect.

The present invention is a bumper stay disposed between a vehicle body member and a reinforcement,
When the reinforcement side is the front end side and the vehicle body member side is the rear end side, the bumper stay is in contact with the rear end side surface of the reinforcement (hereinafter referred to as the R side contact portion). ), A vehicle body member side contact portion (hereinafter referred to as an S side contact portion) that contacts the front end side surface of the vehicle body member, and a connecting portion that connects the R side contact portion and the S side contact portion,
The R-side contact portions are provided at both ends in the width direction of the bumper stay, and the first R-side contact portions positioned on the outer side in the width direction of the vehicle body (hereinafter referred to as the outer side) at the time of attachment and the vehicle body at the time of attachment. A second R-side contact portion located on the inner side in the width direction (hereinafter referred to as the inner side),
The S-side contact portion corresponds to each of the two tip side surfaces of the vehicle body member, and has a first S-side contact portion located outside and a second S-side contact portion located inside.
The connecting portion includes four ribs extending substantially in the front-rear direction of the vehicle, and a rib connecting plate that connects these at the front end side.
When the four ribs are the first rib, the second rib, the third rib, and the fourth rib in order from the outside,
The rear end of the first rib is connected to the outer end of the first S-side contact portion, and the front end is the first R-side contact portion at the inner end of the first R-side contact portion. Connected so that the angle is almost a right angle,
The rear end side end of the fourth rib is connected to the inner end of the second S-side contact portion, and the tip end is formed as the second R-side contact portion at the outer end of the second R-side contact portion. Connected so that the angle is almost a right angle,
Both ends of the rib connecting plate are located more than the junction points of the first rib of the first rib and the first R-side contact portion so that the rib connecting plate is not in contact with the rear end side surface of the reinforcement. It is joined at a position on the rear end side with respect to a position on the rear end side, and a joining point between the fourth rib of the fourth rib and the second R side contact portion,
The second rib has a rear end side end connected to the inner end of the first S-side contact portion, a front end side end connected to the rib connecting plate,
The rear end side end of the third rib is connected to the outer end of the second S-side contact portion, the front end is connected to the rib connecting plate,
At least the second rib, the third rib, and the fourth rib have a bending point that is bent in the middle, and the bending point of the second rib protrudes in a direction away from the first rib. The bumper stay is characterized in that the bent point of the third rib and the bent point of the fourth rib are bent so as to protrude in a direction away from each other.

  The bumper stay has a shape that satisfies all the above-mentioned conditions. As a result, the bumper stay can receive and transmit impact energy when an impact force is applied, has a deformed form with high energy absorption, and can obtain an excellent impact absorbing effect.

That is, when an impact force acts on the reinforcement, impact energy is transmitted to the connecting portion through the R-side contact portion in the bumper stay.
And the said connection part reduces the moment which acts on the part connected with a rib by having the specific structure which consists of the said 4 ribs and the said rib connection board, and propagates impact energy to each rib efficiently. The deformation load can be controlled.

Further, the bending points provided on the ribs serve as buckling base points at the time of deformation, and as described above, the bending points of the second rib protrude in a direction away from the first rib. Since the bending point of the third rib and the bending point of the fourth rib are bent so as to protrude in directions away from each other, the connecting portion is folded in a substantially rhombus shape. This contributes to the pantograph-like deformation. By deforming the connecting portion into a pantograph shape, local deformation can be prevented and the entire connecting portion can be deformed, so that high absorption of impact energy can be achieved.
In addition, since the end portions on the front end side of the first rib and the fourth rib and the R-side contact portion are substantially orthogonal to each other, a sufficient deformation load can be applied to the bending point, contributing to the pantograph-like deformation of the connecting portion. To do.
Such deformation characteristics based on the shape peculiar to the present invention function comprehensively, and as shown in the examples described later, an impact absorbing effect superior to that of the prior art can be obtained.

  Thus, according to the present invention, it is possible to provide a bumper stay capable of obtaining an excellent impact absorbing effect.

FIG. 3 is a cross-sectional view showing a bumper stay in the first embodiment. FIG. 3 is an explanatory diagram showing a load test in Example 1. The graph which shows the result of the load test in Example 1. FIG. FIG. 3 is an explanatory diagram illustrating a bumper stay mounting structure according to the first embodiment. FIG. 3 is an explanatory diagram illustrating a shock absorbing state of a bumper stay in the first embodiment. Sectional drawing which shows the bumper stay as a comparative example. The graph which shows the result of the load test in Experimental example 1. FIG. Sectional drawing before (A) deformation | transformation (B) deformation | transformation of the sample of X = Y / 2 in Experimental example 1. FIG. The graph figure which shows the result of the load test in Experimental example 2. FIG. Sectional drawing before (A) deformation | transformation (B) after deformation | transformation of the sample of Y = 30mm in Experimental example 2. FIG. Sectional drawing before (A) deformation | transformation (B) after a deformation | transformation of the sample of Y = 125mm in Experimental example 2. FIG. The graph which shows the result of the load test in Experimental example 3. FIG. Sectional drawing after the deformation | transformation of the sample A in Experimental example 3. FIG. Sectional drawing after the deformation | transformation of the sample B in Experimental example 3. FIG. The graph figure which shows the result of the load test in Experimental example 4. FIG. Sectional drawing after the deformation | transformation of the sample of T = 5mm in Experimental example 4. FIG. Sectional drawing after the deformation | transformation of the sample of T = 10mm in Experimental example 4. FIG. The graph which shows the result of the load test in Experimental example 5. FIG. Sectional drawing before (A) deformation | transformation (B) deformation | transformation of the sample of t = 3mm in Experimental example 5. FIG. The graph which shows the result of the load test in Experimental example 6. FIG. Explanatory drawing which shows the load test in Experimental example 1. FIG.

  As described above, the bumper stay of the present invention is a bumper stay disposed between a vehicle body member of the vehicle and the reinforcement, and an R-side contact portion that contacts a rear end side surface of the reinforcement, An S-side contact portion that contacts the front end side surface of the vehicle body member; and a connecting portion that connects the R-side contact portion and the S-side contact portion. The bumper stay may be arranged not only on the front (front) side of the vehicle but also on the rear (rear) side. Therefore, when the bumper stay is disposed on the front side of the vehicle, the front side of the vehicle body is the front end side of the bumper stay, while when the bumper stay is disposed on the rear side of the vehicle, The rear side is the tip side of the bumper stay.

The bumper stay is preferably made of an aluminum alloy, more preferably an extruded material of an aluminum alloy. Further, among aluminum alloys, it is particularly preferable that the aluminum alloy is 4000 series, 5000 series, 6000 series, 7000 series, or the like. The bumper stay is preferably made of an extruded material, but may be produced using other processing methods such as welding, casting, and forging.
The bumper stay has a vehicle body width dimension (width) of 150 to 250 mm and a vehicle body longitudinal dimension (length) in order to mount the bumper stay on the vehicle and to generate a good deformation at the time of collision. Is preferably 40 to 120 mm.

The R-side contact portions are provided at both ends in the width direction of the bumper stay, and the first R-side contact portions positioned on the outer side in the width direction of the vehicle body at the time of mounting, and the inner side in the width direction of the vehicle body at the time of mounting. And the second R-side contact portion located at the center.
It is preferable that the front end side surface of the R-side contact portion, which is a surface in contact with the rear end side surface of the reinforcement, has a shape corresponding to the shape of the rear end side surface of the reinforcement.
The length in the width direction of the first R-side contact portion and the second R-side contact portion is that the bumper reinforcement and the bumper stay can be easily assembled and the bumper stay is lightweight. 10 to 50 mm is preferable.

The S-side contact portion has a first S-side contact portion located on the outer side and a second S-side contact portion located on the inner side, corresponding to the two tip side surfaces of the vehicle body member.
The shape of the first S-side contact portion and the second S-side contact portion may be continuous from the viewpoint of easy shape accuracy during extrusion, but from the viewpoint of weight reduction, the first S-side contact portion and the second S-side The contact portion is preferably discontinuous.

The rear end of the first rib is connected to the outer end of the first S-side contact portion, and the front end is the first R-side contact portion at the inner end of the first R-side contact portion. They are connected so that the angle is substantially a right angle. In addition, the rear end of the fourth rib is connected to the inner end of the second S-side contact portion, and the front end is connected to the second R-side contact portion at the outer end of the second R-side contact portion. Are connected so that the angle between the two becomes a substantially right angle.
When the angle formed by the first rib and the first R-side contact portion and the angle formed by the fourth rib and the second R-side contact portion are not substantially perpendicular, the transmission of impact energy to each rib is good. This is not performed, and there is a problem that preferable plastic deformation of the entire connecting portion cannot be obtained, and a sufficient impact absorbing effect cannot be obtained.

Both ends of the rib connecting plate for connecting the four ribs on the front end side are arranged so that the rib connecting plate is not in contact with the rear end side surface of the reinforcement. It is joined at a position on the rear end side with respect to the joint point with the first R-side contact portion and at a position on the rear end side with respect to the joint point between the fourth rib of the fourth rib and the second R-side contact portion.
When the rib connecting plate is in contact with the rear end side surface of the reinforcement, there are problems that abnormal noise is generated due to vibration and black juice is generated. In addition, the transmission of impact energy to each rib is not performed satisfactorily, and the preferable plastic deformation of the entire connecting portion cannot be obtained, and a sufficient impact absorbing effect cannot be obtained.

  The rib connecting plate may be curved, straight, or polygonal. And it is preferable that the said rib connection board is a shape along the shape of the rear-end side surface of the said reinforcement, and it is more preferable that it is single and does not have a bending point.

The second rib has a rear end side end portion connected to the inner end portion of the first S-side contact portion and a front end side end portion connected to the rib connecting plate. Further, the third rib has a rear end side end portion connected to an outer end portion of the second S side contact portion, and a front end side end portion connected to the rib connecting plate.
Depending on the shape of the bumper device, the tip side end portions of the second rib and the third rib are in a good shape when the bumper stay has strength and when the connecting portion is plastically deformed. What is necessary is just to connect to the preferable place of the said rib connection board.

In addition, at least the second rib, the third rib, and the fourth rib have a bending point that is bent halfway, and the bending point of the second rib is in a direction away from the first rib. The bending point of the third rib and the bending point of the fourth rib are bent so as to protrude away from each other.
The angle of the bending point varies depending on the shape of the bumper device.

When the second rib, the third rib, and the fourth rib do not have a bending point, a base point for obtaining a preferable deformation mode of the connecting portion cannot be obtained when the rib is plastically deformed. Further, local deformation or the like may occur, and the impact absorption effect may be reduced.
Further, when the bending point of the second rib is not bent so as to protrude in a direction away from the first rib, the bending point of the third rib and the bending point of the fourth rib are separated from each other. When it is not bent so as to protrude in the direction, a preferable deformation form of the connecting portion cannot be obtained, and the impact absorption effect may be reduced.

  Further, the ribs may be curved or linear from the front end to the bending point and from the rear end to the bending point. When the ribs are linear, the deformation load can be set higher than when the ribs are curved, and a more shock absorbing effect can be obtained. Therefore, the ribs are preferably linear. .

Further, in the bumper stay, the bending point is defined such that a maximum distance in the vehicle front-rear direction between the R side contact portion and the S side contact portion is Y, and a distance from the S side contact portion to the front is Y /. It is preferably located between 3 and Y / 2 (Claim 2).
In this case, the deformation form of the connecting portion can be a particularly good pantograph shape, and a more excellent impact absorbing effect can be obtained.

  Further, when the bending point is provided at a position less than Y / 3 or a position exceeding Y / 2, a base point for obtaining a preferable deformation form of the connecting portion cannot be obtained, and the impact absorbing effect may be reduced. is there.

Moreover, it is preferable that the said bending point is provided on one plane so that all the vehicle front-back direction distances from the said S side contact part may become the same (Claim 3).
In this case, the deformation form of the connecting portion can be a particularly good pantograph shape, and a more excellent impact absorbing effect can be obtained.

  Further, when the bending point is not provided on one plane so that all the distances in the vehicle front-rear direction from the S-side contact portion are the same, a base point for obtaining a preferable deformation form of the connecting portion is obtained. The impact absorbing effect may be reduced.

Further, in the cross-sectional shape, the intersection point of the extension line of the outer side surface of the first rib and the extension line of the rear end side surface of the S-side contact portion is the point A1, and the outer side surface of the first rib and the rear side of the rib connecting plate Assuming that the intersection point with the extended line of the end surface is B1 point, the intersection point between the plane passing through the bending point and the first rib is 8 / of the length of the straight line A1-B1 from the A1 point in the rib 1. When the position is 10 or less, it is preferable to provide a bending point on the first rib.
In this case, the deformation form of the connecting portion can be made a better form, and a more excellent impact absorbing effect can be obtained.

Further, in the cross-sectional shape, the intersection point of the extension line of the inner side surface of the second rib and the extension line of the rear side surface of the S-side contact portion is A2 point, the extension line of the outer side surface of the third rib and the S side When the intersection point with the extension line of the rear end side surface of the contact portion is A3 point, and the intersection point of the extension line of the inner side surface of the fourth rib and the extension line of the rear end side surface of the S side contact portion is A4 point, The length from the A1 point to the A2 point and the length from the A3 point to the A4 point are preferably 20 to 100 mm (Claim 5).
In this case, the bolt can be joined at the time of assembling the vehicle, and the effect that the replacement of the part can be simplified at the time of a light collision can be obtained by the bolt joining.

  If the length from the A1 point to the A2 point and the length from the A3 point to the A4 point are less than 20 mm, the bolt installation width may be insufficient in the case of bolt joining. On the other hand, if the length from the A1 point to the A2 point and the length from the A3 point to the A4 point exceed 100 mm, the joining span during vehicle assembly becomes excessive, and the pair of contact portions There is a risk that the mass will increase because setting is required.

Moreover, it is preferable that the distance from the A2 point to the A3 point coincides with the distance between the two tip side surfaces of the vehicle body member.
In this case, the effect of propagating the collision load to the vehicle body member can be obtained.

  When the distance from the A2 point to the A3 point is less than the distance between the two front end side surfaces of the body member, a moment is generated from the body member side in the propagation of the collision load to the body member. Therefore, there is a possibility that a preferable modified form cannot be obtained. On the other hand, when the distance from the point A2 to the point A3 exceeds the distance between the two side surfaces of the front end of the vehicle body member, the bumper stays on the panel portion, etc. It will deform | transform earlier, and there exists a possibility that sufficient impact absorption effect cannot be acquired. Moreover, in order to cope with this, there exists a possibility that it may become a great mass increase in order to reinforce a panel part etc.

The maximum distance Y in the vehicle front-rear direction between the R-side contact portion and the S-side contact portion is preferably 40 to 120 mm.
In this case, the rib does not fall down, and a pantograph-like deformation form can be obtained.

  When the maximum distance Y in the vehicle front-rear direction between the R-side contact portion and the S-side contact portion is less than 40 mm, it may not be possible to obtain a sufficient impact absorbing effect. On the other hand, when the maximum distance Y exceeds 120 mm, there is a risk of ribs falling sideways.

The total length from the point A2 to the bending point of the second rib and the length from the point A3 to the bending point of the third rib is not more than the length from the point A2 to the point A3. (Claim 8).
In this case, when the rib falls, the second rib and the third rib do not interfere with each other, and a good shock absorbing effect can be obtained.

  When the total length from the point A2 to the bending point of the second rib and the length from the point A3 to the bending point of the third rib exceeds the length from the point A2 to the point A3, When the rib is deformed, the second rib and the third rib interfere with each other, so that a preferable deformation mode of the entire rib cannot be obtained, and a sufficient shock absorbing effect may not be obtained.

Further, an angle θ1 formed between the outer surface of the first rib and the straight line A1-A2, an angle θ2 formed between the inner surface of the second rib and the straight line A2-A1, and an outer surface of the third rib formed with the straight line A3-A4. The angle θ3 and the angle θ4 formed between the inner surface of the fourth rib and the straight line A4-A3 are preferably more than 90 ° and not more than 120 ° (claim 9).
In this case, a good deformation form of the connecting portion can be obtained, and a good impact absorbing effect can be obtained.

  When the formed angle θ1, the formed angle θ2, the formed angle θ3, and the formed angle θ4 are 90 ° or less, the plastic deformation of the rib does not become a panda graph shape, and a sufficient impact absorbing effect is obtained. You may not be able to. On the other hand, when the formed angle θ1, the formed angle θ2, the formed angle θ3, and the formed angle θ4 exceed 120 °, each rib is likely to be deformed excessively, and the impact absorption effect may be reduced. .

Moreover, when the virtual curve which connects the front end side surface of the said 1R side contact part and the said 2nd R side contact part is provided so that it may become a shape along the front end side surface shape of the said rib connection plate, the said rib connection plate from the said virtual curve the longitudinal direction of the vehicle distance to the leading end side, the first 1R side contact portion of the thickness t _1r, when the thickness of the first 2R-side contact portion and t _2r, of t _1r ~2t _1r and t _2r ~2t _2r It is preferable to be within the range (claim 10).

In this case, the effect of moment reduction by the input from the reinforcement is obtained, and a stable deformation form can be obtained.
Normally, the imaginary curve connecting the first R-side contact portion and the front end side surface of the second R-side contact portion is the rear end side surface of the reinforcement.

When the distance in the vehicle front-rear direction from the virtual curve to the tip side surface of the rib connecting plate is smaller than at least one of t _1r and t _2r , when the impact force is applied, the reinforcement and the rib There is a possibility that the connecting plate may come into contact, and a preferable deformation form of the entire rib cannot be obtained, and the effect of reducing the moment may not be sufficiently obtained. On the other hand, when the distance in the vehicle front-rear direction from the virtual curve to the tip side surface of the rib connecting plate exceeds at least one of 2t _1r and 2t _2r , the first rib and the fourth rib are in contact with the R-side contact portion. There is a possibility that deformation occurs between the joint point and the joint point with the rib connecting plate, so that a preferable deformation form of the entire rib cannot be obtained, and a sufficient impact absorbing effect may not be obtained.

The thicknesses of the first to fourth ribs and the rib connecting plate are equal to or less than the thicknesses of the first R-side contact portion, the second R-side contact portion, the first S-side contact portion, and the second S-side contact portion. (Claim 11).
In this case, a pantograph-like deformation form is obtained by input from the bumper reinforcement, and a sufficient impact absorbing effect can be obtained.

  When the thicknesses of the first to fourth ribs and the rib connecting plate exceed the thicknesses of the first R-side contact part, the second R-side contact part, the first S-side contact part, and the second S-side contact part There is a risk that the pantograph-like deformation will not be achieved.

Moreover, it is preferable that the thickness of the said 1st rib-the 4th rib which comprises the said connection part, and the said rib connection board is 1.0-3.0 mm (Claim 12).
In this case, the bumper stay can have sufficient strength, and a panda graph-like deformation of the rib of the connecting portion can be obtained, and an excellent impact absorbing effect can be obtained.

When the thicknesses of the first to fourth ribs and the rib connecting plate are less than 1.0 mm, the extrudability is poor and it is difficult to produce a product, and the ribs are seated at points other than the bending point. There is a risk of bending. Moreover, when producing this bumper stay by welding joining etc., there exists a possibility that distortion may generate | occur | produce and a favorable shape may not be obtained. On the other hand, when the thicknesses of the first to fourth ribs and the rib connecting plate exceed 3.0 mm, the weight of the bumper stay increases, which is not preferable from the viewpoint of weight reduction.
Further, the thicknesses of the first to fourth ribs may all be equal or different from each other.

Moreover, it is preferable that the thickness of the said 1R side contact part, the said 2nd R side contact part, the said 1st S side contact part, and the said 2nd S side contact part is 2.0-6.0 mm. ).
In this case, the bumper stay can have sufficient strength.

  When the thickness of the first R-side contact portion, the second R-side contact portion, the first S-side contact portion, and the second S-side contact portion is less than 2.0 mm, the fastening torque for bolt fastening during vehicle assembly May become insufficient. On the other hand, when the thickness of the first R-side contact portion, the second R-side contact portion, the first S-side contact portion, and the second S-side contact portion exceeds 6.0 mm, the weight of the bumper stay increases, so that the weight is reduced. It is not preferable from the viewpoint of conversion.

Example 1
In this example, a bumper stay according to an embodiment of the present invention will be described with reference to FIGS. In consideration of the thickness of each part, it is considered that it is not appropriate to indicate the connection position of each part with one point. For convenience of explanation, the connection part of each part is shown as a region surrounded by a round broken line. .

As shown in FIGS. 1 and 4, the bumper stay 1 of the present example is disposed between a vehicle body member 8 and a reinforcement 7 of the vehicle. When the reinforcement 7 side is the front end side and the vehicle body member 8 side is the rear end side, the bumper stay 1 has an R-side contact portion 2 that contacts the rear end side surface of the reinforcement 7. In addition, the S-side contact portion 3 that comes into contact with the front end side surface of the vehicle body member 8 including the main body portion 81 and the two flange portions 82 disposed on the front end side of the main body portion 81 in the vehicle body width direction, and the R side It has the connection part 4 which connects the contact part 2 and the S side contact part 3.
The bumper stay 1 is made of an extruded material of an aluminum alloy having a material, quality: 6N01-T5, and proof stress: 220 MPa.
Further, the corner portion of the bumper stay 1 has an R shape.

  The R-side contact portion 2 is provided at both ends of the bumper stay 1 in the width direction, and is attached to the first R-side contact portion 21 positioned on the outer side in the width direction of the vehicle body (hereinafter referred to as the outer side) when attached. The second R-side contact portion 22 is located on the inner side in the width direction of the vehicle body (hereinafter referred to as the inner side).

The S-side contact portion 3 corresponds to the front end side surfaces of the two flange portions 82 of the vehicle body member 8, and includes a first S-side contact portion 31 located outside and a second S-side contact portion 32 located inside. Have.
The connecting portion 4 includes four ribs 41 extending substantially in the front-rear direction of the vehicle, and a rib connecting plate 42 that connects them on the front end side.

  Assuming that the four ribs 41 are the first rib 43, the second rib 44, the third rib 45, and the fourth rib 46 in order from the outside, the rear end portion 432 of the first rib 43 has the first S. Connected to the outer end 311 of the side contact portion 31, and the tip end 431 is connected so that the angle α formed with the first R side contact portion 21 at the inner end 212 of the first R side contact portion 21 is substantially a right angle. In the fourth rib 46, the rear end side end 462 is connected to the inner end 322 of the second S side contact portion 32, and the front end side end 461 is the outer end 221 of the second R side contact portion 22. Are connected so that an angle formed with the second R-side contact portion 22 is substantially a right angle.

  Both ends of the rib connecting plate 42 are connected to the first rib 43 and the first R-side contact portion 21 of the first rib 43 so that the rib connecting plate 42 is not in contact with the rear end side surface of the reinforcement. It is joined to the position Q1 on the rear end side from the joining point P1 and the position Q4 on the rear end side from the joining point P4 between the fourth rib 46 of the fourth rib 46 and the second R-side contact portion 22. .

  The second rib 44 has a rear end portion 442 connected to the inner end portion 312 of the first S-side contact portion 31, a front end portion 441 connected to the rib connecting plate 42, and the third rib 45. The rear end portion 452 is connected to the outer end portion 321 of the second S-side contact portion 32, and the front end portion 451 is connected to the rib connecting plate 42.

The second rib 44, the third rib 45, and the fourth rib 46 have a bending point 47 that is bent halfway. Further, the bending point 47 of the second rib 45 is bent so as to protrude in a direction away from the first rib 43, and the bending point 47 of the third rib 45 and the bending point 47 of the fourth rib 46. Are bent so as to protrude in directions away from each other, and the bending point 47 is provided on one plane at a position where the distance X from the S-side contact portion 3 to the front is 30.9 mm.
The maximum distance Y in the vehicle front-rear direction between the R-side contact portion 2 and the S-side contact portion 3 is 78.2 mm, and the position of the bending point 47 is a distance from the S-side contact portion 3 to the front. Is located between Y / 3 and Y / 2.

  Further, in the cross-sectional shape, an intersection point between the extension line of the outer side surface of the first rib 43 and the extension line of the rear end side surface of the S-side contact portion 3 is the point A1, and the extension line of the inner side surface of the second rib 44 The intersection point between the extension line of the rear end side surface of the S side contact portion 3 and the extension line of the outer side surface of the third rib 45 and the extension line of the rear end side surface of the S side contact portion 3 is A3. Point, when the intersection of the extension line of the inner side surface of the fourth rib 46 and the extension line of the rear side surface of the S-side contact portion 3 is A4 point, the length L from the point A1 to the point A2 Is 52 mm, and the length M from the A3 point to the A4 point is 51 mm.

  The total length from the point A2 to the bending point 47 of the second rib and the length from the point A3 to the bending point 47 of the third rib is 60.18 mm, and the point from the A2 to the point A3. Or less than the length N (= 62.5 mm).

Further, the angle θ1 formed between the outer surface of the first rib 43 and the straight line A1-A2 is 113.8 °, and the angle θ2 formed between the inner surface of the second rib 44 and the straight line A2-A1 is 94.7 °. The angle θ3 formed between the outer surface of the third rib 45 and the straight line A3-A4 is 98.5 °, and the angle θ4 formed between the inner surface of the fourth rib 46 and the straight line A4-A3 is 96.2 °. is there.
An angle θ5 formed between the inner side surface of the second rib and the tip side surface of the rib connecting plate 42 is 72.6 °, and an angle θ6 formed between the outer side surface of the third rib and the tip side surface of the rib connecting plate 42 is. Is 89.3 °.

Moreover, the thicknesses of the first rib 43 to the fourth rib 46 and the rib connecting plate 42 constituting the connecting portion 4 are all 2 mm.
Further, the thickness (t _1r ) of the first R-side contact portion 21, the thickness (t _2r ) of the second R-side contact portion 22, the thickness of the first S-side contact portion 31, and the thickness of the second S-side contact portion 32. Are all 4 mm.
Moreover, from the virtual curve 23 which has the shape along the front end side shape of the said rib connection plate 42 from the front end side surface of the said 1R side contact part 21 and the said 2nd R side contact part 22 to the front end side surface of the said rib connection plate 42 The distance T in the vehicle front-rear direction is 7 mm.
Moreover, the width direction length U of the first R-side contact portion is 30 mm, and the width direction length V of the second R-side contact portion is 28 mm.

In this example, the impact absorbing effect of the bumper stay 1 was evaluated.
As shown in FIG. 2, a rigid body 5 (same shape as a reinforcement) bent to an inner radius R = 3000 mm along the longitudinal direction is provided with the bumper stay 1 and a support base 6 for supporting the bumper stay 1 in the downward direction. Used and supported with a span S = 800 mm. The support base 6 includes a main body 61 and two flanges 62 disposed in the width direction at the upper end of the main body 61. A load test was performed in which a load F was applied from the outer R side of the rigid body 5 through the rigid body 5. Note that the distance from the point A2 to the point A3 matches the distance H between the two end side surfaces (flange portions 62) of the support base 6.
The load was continuously measured with a load cell of a testing machine.
At the load application position of the rigid body 5 of the bumper stay 1, a displacement meter was attached to the portion G on the opposite surface of the load F, and the displacement was continuously measured.

For comparison, a similar test was performed on a general bumper stay 9 shown in FIG.
As shown in FIG. 6, the bumper stay 9 includes an R-side contact portion 91 facing the reinforcement side, an S-side contact portion 92 facing the vehicle body member side, the R-side contact portion 91 and the S-side. It has a structure composed of a plurality of ribs 93 that join the contact portion 92. The R-side contact portion 91 includes a first R-side contact portion 911, a second R-side contact portion 912, and a third R-side contact portion 913 that are separated from each other. The S-side contact portion 92 is separated from the first S-side contact portion 921. And the second S-side contact portion 922, and the rib 93 includes four ribs (931 to 934). Moreover, the joint part of the said rib 93 and the said R side contact part 91 and the said rib 93 and the said S side contact part 92 becomes R shape.

The bumper stay 9 is made by press-molding a single steel material. And the thickness of the said steel material is 2 mm. The bumper stay 9 as a whole has a width direction of 243.4 mm and a vehicle length direction of 76 mm.
In the bumper stay 9, the first R-side contact portion 911 is 32 mm in the width direction, the second R-side contact portion 912 is 53.7 mm in the width direction, and the third R-side contact portion 913 is 32 mm in the width direction. The first S-side contact portion 921 is 52 mm in the width direction, and the second S-side contact portion 922 is 51 mm in the width direction. In FIG. 6, the angle θ7 is 106.7 °, the angle θ8 is 94.7 °, the angle θ9 is 98.5 °, and the angle θ10 is 96.2 °.

  And the result of the said load test is shown in FIG. In FIG. 3, the horizontal axis represents displacement (mm) and the vertical axis represents load (kN). In FIG. 3, a solid line E shows the result of the bumper stay 1 of this example, and a broken line C shows the result of the bumper stay 9 as a comparative example.

  From FIG. 3, the bumper stay 1 of this example can reduce the displacement with the same load as compared with the bumper stay 9 as a comparative example. On the other hand, the same displacement can withstand high loads. That is, the bumper stay 1 of this example has a higher impact absorbing effect than the bumper stay 9 of the comparative example. Further, it can be seen that the bumper stay 1 of this example has a quick load rise and controls the deformation load, so that a high average load can be achieved.

  Thus, according to this example, it can be seen that a bumper stay capable of obtaining an excellent impact absorbing effect can be provided.

  FIG. 4 is a developed view showing a state in which the bumper stay is disposed between the vehicle body member 8 and the reinforcement 7 of the vehicle. As shown in the drawing, the bumper stay 1 is connected to the front end of the flange portion 82 of the vehicle body member 8 of the vehicle, which includes a main body portion 81 and two flange portions 82 disposed on the front end side of the main body portion 81 in the vehicle body width direction. The reinforcement 7 that is fixed to the surface and extends in the lateral direction is attached to the vehicle body via the bumper stay 1.

  FIG. 5 shows a modified form when the bumper stay receives an impact. FIG. 5A shows the mounting state before receiving an impact. When an impact force of a predetermined level or more is applied to the bumper device, as shown in FIG. 5B, all the ribs 41 (rib 43 to rib 46) of the bumper stay 1 are deformed to form a pantograph shape. To absorb.

(Experimental example 1)
A sample in which the shape of the bumper stay 1 in Example 1 was changed was created, and the impact absorbing effect was evaluated.
In the same manner as in Example 1, four types of samples having different distances X were prepared using an extruded material of aluminum alloy having a material, identification: 6N01-T5, and proof stress: 220 MPa. In each sample, the distance X was set to Y / 1.5, Y / 2, Y / 3, and Y / 4, respectively. θ1 to θ4 were changed according to each case. Other dimensions are the same as those in the first embodiment.
In addition, the bending point 47 was provided also to the 1st rib 43 in the sample of Y / 3 and Y / 4. This is because the intersection of the plane passing through the bending point 47 and the first rib 43 is a position that is 8/10 or less of the length of the straight line A1-B1 from the point A1.

As shown in FIG. 21, a compression test was performed in which the S-side contact portion 3 of each sample was supported by a support base 6 and the load portion applied a load via a rigid body 5 having the same shape as the reinforcement 7 as a load jig. . And the displacement was measured in the position J of FIG.
A sample having a load in the range of 600 to 750 N / mm and having a displacement of 20 mm or more is a sample excellent in shock absorption.

  The measurement results are shown in FIG. As shown in the figure, the samples with the distance X of Y / 1.5 and Y / 4 had a displacement of less than 20 mm, and the deformed ribs interfered with each other, so that the deformation stopped and the load increased. In contrast, the samples with the distance X of Y / 2 and Y / 3 were within the preferable range of the load and were displaced by 20 mm or more.

  FIG. 8A shows a cross-sectional shape of the sample with X = Y / 2 before deformation. FIG. 8B shows a cross-sectional shape of the sample after deformation (displacement 10 mm). As shown in the figure, in this sample, the ribs 43 to 46 are bent well without falling sideways.

  From the above, it can be seen that the samples with the distance X of Y / 2 and Y / 3 are more excellent in impact absorbing performance than the samples of Y / 1.5 and Y / 4. Therefore, when manufacturing the bumper stay 1, it is considered preferable to set the distance X within the range of Y / 3 to Y / 2.

(Experimental example 2)
A sample in which the distance Y of the bumper stay 1 in Example 1 was changed was created, and the impact absorption effect was evaluated.
Using the same material as in Example 1, four types of samples with different distances Y were prepared. Each sample was Y = 30, 50, 115, and 125 mm, respectively. The width direction dimension and thickness of each sample are the same as in Example 1. Y / X was also set to the same value as in Example 1. With the change of Y, θ1 to θ4 were changed.

  A load was applied to each sample under the same conditions as in Experimental Example 1, and the displacement was measured. Further, as in Experimental Example 1, the load was in the range of 600 to 750 N / mm, and the sample that was displaced by 20 mm or more was evaluated as a sample having an excellent impact absorbing effect.

The measurement results are shown in FIG. 10A and 10B show cross-sectional views before and after the deformation of the Y = 30 mm sample, and FIGS. 11A and 11B show cross-sectional views before and after the Y = 125 mm deformation. Show.
As shown in FIGS. 9 and 10, in the sample with Y = 30 mm, since Y is small, the ribs were crushed and interfered, and the load increased linearly. Moreover, it did not deform | transform, unless a big load was added compared with another sample.
On the other hand, the sample with Y = 50 and 115 mm was within the preferable load range.
Further, as shown in FIG. 11, in the sample with Y = 125 mm, since Y was too large, the ribs fell sideways. As shown in FIG. 9, this sample was deformed with a smaller load than the sample of Y = 50, 115 mm.
From the above, it can be seen that the sample of Y = 50, 115 mm is superior in impact absorption performance than the other samples. Moreover, when manufacturing the bumper stay 1 from the said experiment, it is thought that it is preferable to set Y to 40-120 mm.

(Experimental example 3)
Samples in which the rib angles θ2 to θ4 of the bumper stay 1 in Example 1 were changed were created, and the impact absorption effect was evaluated.
Using the same material as in Example 1, the following two types of samples were prepared.
Sample A: θ3, θ4 = 94.7 °, θ2 = 100 °
Sample B: θ4 = 90 °, θ2, θ3 = 85 °
In Samples A and B, the dimensions other than the above are the same as those in Example 1.

  A load was applied to each sample under the same conditions as in Experimental Example 1, and the displacement was measured. Further, as in Experimental Example 1, the load was in the range of 600 to 750 N / mm, and the sample that was displaced by 20 mm or more was evaluated as a sample having an excellent impact absorbing effect.

The measurement results are shown in FIG. Moreover, the cross-sectional shape after deformation of the sample A is shown in FIG. 13, and the cross-sectional shape after deformation of the sample B is shown in FIG.
As shown in FIG. 12, although both the samples A and B were within the preferred range, the deformation states of both were different. That is, as shown in FIG. 13, the sample A was deformed with a good rib shape with the bending point 47 as a base point. On the other hand, in the sample B, as shown in FIG. 14, the third rib 45 falls sideways, the second rib 44 deforms toward the first rib 43 at the bending point 47, and deforms in an unstable shape as a whole. I understood that.
From the above, sample A in which all rib angles θ1 to θ4 are greater than 90 ° and equal to or less than 120 ° is superior in impact absorption effect to sample B in which all rib angles θ1 to θ4 are out of this range. I understand.

(Experimental example 4)
A sample in which the above T of the bumper stay 1 in Example 1 was changed was prepared, and the impact absorbing effect was evaluated.
Using the same material as in Example 1, three types of samples with different T were prepared. In each sample, the thickness of the R-side contact portion 2 was set to t = 3 mm, and T was set to 5, 7, and 10 mm, respectively. Dimensions other than the above were the same as in Example 1.

  A load was applied to each sample under the same conditions as in Experimental Example 1, and the displacement was measured. Further, as in Experimental Example 1, the load was in the range of 600 to 750 N / mm, and the sample that was displaced by 20 mm or more was evaluated as a sample having an excellent impact absorbing effect.

The measurement results are shown in FIG. Further, a cross-sectional view after deformation of T = 5 mm is shown in FIG. 16, and a cross-sectional view after deformation of T = 10 mm is shown in FIG.
The sample with T = 5 mm was within the preferable load range as shown in FIG. Further, as shown in FIG. 16, it was found that the second R-side contact portion 22 of the fourth rib 46 and the rib connecting plate did not deform, and the rib connecting plate 42 hardly deformed, resulting in a preferable deformed shape. .
On the other hand, as shown in FIG. 15, the sample with T = 7 and 10 mm is only slightly higher in load than the sample with T = 5 mm, but since T exceeds 2t, The 4 ribs 46 were deformed so as to fall in the direction of the second R-side contact portion 22, and the rib connecting plate 42 was greatly deformed in the vicinity of the joint point with the fourth rib 46.
From the above, it can be seen that the sample with T = 5 mm is more excellent in impact absorbing effect than the other samples. Further, when manufacturing the bumper stay 1, the above experiment, it is considered preferable to a T in the range of t _1r ~2t _1r and t _2r ~2t _2r.

(Experimental example 5)
Samples with different thicknesses t of the ribs 43 to 46 and the rib connecting plate 42 of the bumper stay 1 in Example 1 were prepared, and the impact absorbing effect was evaluated.
Using the same material as in Example 1, four types of samples with different t were prepared. Each sample was set to t = 1, 2, 3, 4 mm, respectively. Moreover, the thickness of the contact part 2 was 3 mm. Other dimensions were the same as in Example 1.

  A load was applied to each sample under the same conditions as in Experimental Example 1, and the displacement was measured. Further, as in Experimental Example 1, the load was in the range of 600 to 750 N / mm, and the sample that was displaced by 20 mm or more was evaluated as a sample having an excellent impact absorbing effect.

The measurement results are shown in FIG. Further, cross-sectional views before and after the deformation at t = 3 mm are shown in FIGS. 19 (A) and 19 (B).
As shown in FIG. 18, the sample of t = 4 mm was not displaced unless a large load was applied. On the other hand, the samples with t = 1, 2, 3 mm were within the preferable load range.
Further, as shown in FIG. 19, the sample with t = 3 mm has a good deformed shape of the rib.
From the above, it can be seen that the samples with t = 1, 2, and 3 mm are more excellent in impact absorbing effect than t = 4 mm. Moreover, when manufacturing the bumper stay 1 from the said experiment, it is thought that it is preferable to make thickness t of the ribs 43-46 and the rib connection board 42 into 1.0-3.0 mm.

(Experimental example 6)
Samples in which the thicknesses t _1r and t _2r of the R-side contact portion 2 of the bumper stay 1 in Example 1 were changed were prepared, and the impact absorption effect was evaluated.
Using the same material as in Example 1, four types of samples having different t _1r and t _2r were prepared. In each sample, t _1r and t _2r were set to 1, 2, 3, 6, and 7 mm, respectively. Other dimensions were the same as in Example 1.

  A load was applied to each sample under the same conditions as in Experimental Example 1, and the displacement was measured. Further, as in Experimental Example 1, the load was in the range of 600 to 750 N / mm, and the sample that was displaced by 20 mm or more was evaluated as a sample having an excellent impact absorbing effect.

The measurement results are shown in FIG. As shown in the figure, the samples with t _1r and t _{2r of 2} , 3, 6 mm were within the preferable load range.
On the other hand, the sample with t _1r and t _2r of 1 mm was deformed before a sufficient load was applied.
Further, the sample with t _1r and t _2r of 7 mm did not deform unless a large load was applied.

From the above, it can be seen that samples with t _1r and t _{2r of 2, 3} , 6 mm are superior in impact absorption effect compared to other samples. Further, from the above experiment, when manufacturing the bumper stay _1, it is considered preferable to the _{t 1r} and _{t 2r} to 2.0 to 6.0 mm.

DESCRIPTION OF SYMBOLS 1 Bumper stay 2 R side contact part 21 1R side contact part 22 2R side contact part 3 S side contact part 31 1st S side contact part 32 2S side contact part 4 Connection part 41 Rib 42 Rib connection plate

Claims (13)

A bumper stay disposed between a vehicle body member and a reinforcement,
When the reinforcement side is the front end side and the vehicle body member side is the rear end side, the bumper stay is in contact with the rear end side surface of the reinforcement (hereinafter referred to as the R side contact portion). ), A vehicle body member side contact portion (hereinafter referred to as an S side contact portion) that contacts the front end side surface of the vehicle body member, and a connecting portion that connects the R side contact portion and the S side contact portion,
The R-side contact portions are provided at both ends in the width direction of the bumper stay, and the first R-side contact portions positioned on the outer side in the width direction of the vehicle body (hereinafter referred to as the outer side) at the time of attachment and A second R-side contact portion located on the inner side in the width direction (hereinafter referred to as the inner side),
The S-side contact portion corresponds to each of the two tip side surfaces of the vehicle body member, and has a first S-side contact portion located outside and a second S-side contact portion located inside.
The connecting portion includes four ribs extending substantially in the front-rear direction of the vehicle, and a rib connecting plate that connects these at the front end side.
When the four ribs are the first rib, the second rib, the third rib, and the fourth rib in order from the outside,
The rear end of the first rib is connected to the outer end of the first S-side contact portion, and the front end is the first R-side contact portion at the inner end of the first R-side contact portion. Connected so that the angle is almost a right angle,
The rear end side end of the fourth rib is connected to the inner end of the second S-side contact portion, and the tip end is formed as the second R-side contact portion at the outer end of the second R-side contact portion. Connected so that the angle is almost a right angle,
Both ends of the rib connecting plate are located more than the junction points of the first rib of the first rib and the first R-side contact portion so that the rib connecting plate is not in contact with the rear end side surface of the reinforcement. It is joined at a position on the rear end side with respect to a position on the rear end side, and a joining point between the fourth rib of the fourth rib and the second R side contact portion,
The second rib has a rear end side end connected to the inner end of the first S-side contact portion, a front end side end connected to the rib connecting plate,
The rear end side end of the third rib is connected to the outer end of the second S-side contact portion, the front end is connected to the rib connecting plate,
At least the second rib, the third rib, and the fourth rib have a bending point that is bent in the middle, and the bending point of the second rib protrudes in a direction away from the first rib. Bumper stay characterized in that it is bent, and the bending point of the third rib and the bending point of the fourth rib are bent so as to protrude away from each other.   2. The bending point according to claim 1, wherein the distance from the S-side contact portion to the front is Y / 3 to Y, where Y is the maximum distance in the vehicle front-rear direction between the R-side contact portion and the S-side contact portion. Bumper stay characterized by being located between Y / 2.   3. The bumper stay according to claim 1, wherein the bending points are provided on a single plane so that all the distances in the vehicle front-rear direction from the S-side contact portion are the same.   4. The cross-sectional shape according to claim 3, wherein an intersection of an extension line of the outer side surface of the first rib and an extension line of a rear end side surface of the S-side contact portion is a point A1, and the outer side surface of the first rib is connected to the rib. Assuming that the intersection point with the extension line of the rear end side surface of the plate is point B1, the intersection point between the plane passing through the bending point and the first rib is the length of the straight line A1-B1 from the point A1 in the rib 1. The bumper stay is characterized in that a bending point is provided in the first rib when the position is 8/10 or less.   5. The cross-sectional shape according to claim 1, wherein, in the cross-sectional shape, an intersection point between the extension line of the inner side surface of the second rib and the extension line of the rear end side surface of the S-side contact portion is A2 point, and the third rib An intersection of the extension line of the outer side surface of the S-side contact portion and the extension line of the rear end side surface of the S-side contact portion, and the extension line of the inner side surface of the fourth rib and the extension line of the rear end side surface of the S-side contact portion A bumper stay characterized in that the length from the point A1 to the point A2 and the length from the point A3 to the point A4 are 20 to 100 mm when the intersection point is A4.   6. The bumper stay according to claim 1, wherein a distance from the point A <b> 2 to the point A <b> 3 coincides with an interval between the two end side surfaces of the vehicle body member.   The bumper stay according to any one of claims 1 to 6, wherein a maximum distance Y in the vehicle front-rear direction between the R-side contact portion and the S-side contact portion is 40 to 120 mm.   In any 1 item | term of Claims 1-7, the sum total of the length from the said A2 point to the bending point of the said 2nd rib and the length from the said A3 point to the bending point of the said 3rd rib is from said A2 point. A bumper stay characterized in that it is not longer than the length up to point A3.   9. The angle θ <b> 1 formed between the outer surface of the first rib and the straight line A <b> 1-A <b> 2, the angle θ <b> 2 formed between the inner surface of the second rib and the straight line A <b> 2-A <b> 1, the third rib The bumper stay is characterized in that the angle θ3 formed by the straight line A3-A4 with the outer surface of the straight line and the angle θ4 formed by the straight line A4-A3 with the inner surface of the fourth rib are more than 90 ° and 120 ° or less. 10. The virtual curve connecting the first R-side contact portion and the distal end side surface of the second R-side contact portion according to claim 1 is provided so as to have a shape along the distal end side shape of the rib connecting plate. If the vehicle front-rear direction of the distance from the virtual curve to the tip side of the rib connecting plate, said first 1R side contact portion of the thickness t _1r, the thickness of the first 2R-side contact portion when the t _2r, t _1r Bumper stay characterized by being in the range of ˜2t _1r and t _2r ˜2t _2r .   The thickness of the said 1st rib-4th rib and the said rib connection board in any one of Claims 1-10 is the said 1R side contact part, the 2nd R side contact part, the 1st S side contact part, and A bumper stay having a thickness equal to or less than a thickness of the second S-side contact portion.   The bumper stay according to claim 11, wherein the first to fourth ribs and the rib connecting plate constituting the connecting portion have a thickness of 1.0 to 3.0 mm.   In Claim 11 or 12, Thickness of the 1st R side contact part, the 2nd R side contact part, the 1st S side contact part, and the 2nd S side contact part is 2.0-6.0 mm. A unique bumper stay.

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