JP2018177125A - Vehicle roof structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle roof structure which enables a weight reduction of a roof arch and can secure a vehicle cabin space during a vehicle collision.SOLUTION: A vehicle roof structure 1 forming a roof portion of a vehicle has a roof arch 10 extending in a vehicle width direction. The roof arch 10 is configured to include: support skeleton parts 13 individually provided at left and right corner portions of an arch skeleton 11 in a curved shape; and energy absorption parts 17 which are provided on outer surfaces 13a of the support skeleton parts 13 of the arch skeleton 11 in a deformable manner so as to absorb energy generated in an early stage of a collision.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a roof structure of a vehicle.

Patent Document 1 below discloses a roof structure of a bus vehicle. The roof structure is provided with a plurality of metal roof bow units (hereinafter referred to as "roof arches") extending along the vehicle width direction. In this roof arch, left and right corner portions are reinforced in order to secure a cabin space at the time of a vehicle collision such as when the vehicle rolls over. Specifically, the roof arch has a fan-like shape such that the width when the corner portion is viewed from the side extends downward, and the reinforcing plate is attached to the corner portion. There is.
According to the roof arch having such a reinforcing structure, it is possible to secure the cabin space by suppressing the displacement (stroke amount) of the corner portion in the direction of the cabin at the time of a vehicle collision within the target value.

JP, 2010-89755, A

  However, in the case of the roof structure disclosed in Patent Document 1, there is a problem that the weight of the roof arch increases by reinforcing the corner portion, and the fuel consumption is deteriorated or the operability of the vehicle is reduced due to the influence of the weight increase. It can occur. However, if the reinforcement of the corner is weakened by the weight reduction of the roof arch, this corner is likely to be deformed due to buckling or the like, so the displacement of the corner toward the cabin increases and the cabin space is secured. It is difficult to obtain the desired collision safety performance. In addition, such a problem may occur not only in the bus roof structure but also in the roof structure of vehicles other than the bus.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a vehicle roof structure capable of reducing the weight of a roof arch and securing a cabin space at the time of a vehicle collision.

One aspect of the present invention is
A vehicle roof structure having a roof arch extending along a vehicle width direction, comprising:
The roof arch includes a support frame portion provided in a curved shape at each of left and right corner portions, and an energy absorbing portion provided on an outer surface of the support frame portion so as to be able to absorb energy at the initial stage of collision. , A vehicle roof structure,
It is in.

According to the above-described vehicle roof structure, a collision load initially acts on the energy absorbing portions at the left and right corner portions of the roof arch in the event of a vehicle collision. At this time, the energy absorbing portion can absorb the energy at the initial stage of the collision by being deformed by receiving the collision load. In addition, the support frame portion can support the energy absorbing portion at the time of deformation.
Here, “deformation” refers to plastic deformation such that the whole or a part of the energy absorbing part does not return to its original shape even when the load is removed, and a failure such as a crack or break in the whole or a part of the energy absorbing part A wide range of deformation is also widely included, such as deformation resulting in failure after plastic deformation of all or part of the energy absorbing portion.
In this case, there is no need to reinforce the energy absorbing portion to counter the collision load, and the weight of that portion can be reduced, while the amount of displacement of the corner portion of the roof arch toward the cabin by reinforcing only the support frame portion (Stroke amount) can be kept within the target value.

  As described above, according to the above aspect, in the vehicle roof structure, it is possible to reduce the weight of the roof arch and secure the cabin space at the time of the vehicle collision.

FIG. 2 is a front view of the vehicle frame structure according to the first embodiment, viewed obliquely from below. The perspective view of the roof arch in FIG. Sectional drawing of the corner part of the roof arch of FIG. The figure which shows the mode of the initial state to which collision load was input into the roof arch of FIG. The figure which shows typically a mode that the energy absorption part of the roof arch was plastically deformed in FIG. The figure which shows typically a mode that the energy absorption part of the roof arch further plastically deformed in FIG. FIG. 7 is a diagram schematically showing the correlation between the load received by the roof arch and the displacement in the first embodiment together with a comparative example. Sectional drawing of the corner part of the roof arch of the vehicle roof structure of Embodiment 2. FIG. Sectional drawing of the corner part of the roof arch of the vehicle roof structure of Embodiment 3. FIG.

  Preferred embodiments of the above aspects are described below.

  In the above-described vehicle roof structure, preferably, the support frame portion is configured to be elastically deformed in accordance with a load received from the deformed energy absorbing portion over both the energy absorbing portion in terms of both strength and rigidity.

  According to this vehicle roof structure, after the energy absorbing portion is deformed, the load received by the support frame portion from the energy absorbing portion can be hardly fluctuated in the elastic deformation region.

  In the above-described vehicle roof structure, preferably, the energy absorbing portion is a box structure having a hollow portion, and the energy is absorbed by the box structure being crushed and plastically deformed.

  According to the vehicle roof structure, by using the box structure that is easily plastically deformed as the energy absorbing portion, the load that the energy absorbing portion receives in the initial stage of the collision can be suppressed low.

  In the vehicle roof structure described above, it is preferable that a plurality of the box structures are disposed along the curved shape of the support frame portion.

  According to this vehicle roof structure, it becomes possible to prevent the one box structure from being plastically deformed in the direction away from the collision load input direction by supporting the adjacent box structure. Also, a wide range along the curved shape of the support skeleton can be used for energy absorption at the initial stage of collision.

  In the above-described vehicle roof structure, the support frame portion includes a first plate portion and a second plate portion spaced apart from each other in the collision load input direction, and the first plate portion and the second plate portion. Preferably, it is constituted by a rib structure having a plurality of ribs interposed therebetween.

  According to this vehicle roof structure, by forming the support frame portion using the rib structure composed of a plurality of ribs, it is possible to reinforce the support frame portion after reducing its weight.

  In the above-described vehicle roof structure, the plurality of ribs preferably include cross ribs made of two ribs intersecting each other.

  According to this vehicle roof structure, the support skeleton can be reinforced to a desired level by a small number of ribs.

  In the above-described vehicle roof structure, it is preferable that the roof arch includes a horizontal portion continuously extending horizontally to the support frame portion, and the horizontal portion is configured by the rib structure.

  According to this vehicle roof structure, both the horizontal portion of the roof arch and the support framework can be reinforced by the rib structure.

  In the vehicle roof structure described above, the roof arch is preferably configured as a resin molded portion in which the support frame portion and the energy absorbing portion are integrally formed of a resin material.

  This vehicle roof structure is effective in reducing the weight of the roof arch.

  Hereinafter, an embodiment of a vehicle roof structure of a roof portion of a bus vehicle which is one of the vehicles will be described with reference to the drawings.

  In the drawings for describing this embodiment, unless otherwise specified, the front of the vehicle is indicated by arrow FR, the upper side of the vehicle is indicated by arrow UP, the right of the vehicle is indicated by arrow R, and the left of the vehicle is indicated by arrow L It shall be. Further, the vehicle width direction which is the left-right direction is indicated by arrow X, the front-rear direction is indicated by arrow Y, and the input direction of the collision load is indicated by arrow D.

(Embodiment 1)
As shown in FIG. 1, a vehicle roof structure (hereinafter simply referred to as “roof structure”) 1 constituting a bus vehicle has a roof panel 2 forming a design surface of the roof and a framework structure supporting the roof panel 2. The body 3 is provided.

  The skeletal structure 3 extends along the vehicle width direction X with a pair of left and right side roof rail portions 4L and 4R extending in the front-rear direction, and left and right pillar portions 5L and 5R extending in the vertical direction. A plurality of existing roof arches 10 are provided. The side roof rail portions 4L and 4R and the pillar portions 5L and 5R are all made of a metal material.

  In the plurality of roof arches 10, a first roof arch 10A arranged to be continuous with the pillars 5L, 5R, and a second roof arch 10B arranged at a position deviated from the extension of the pillars 5L, 5R ,It is included.

  Since the two roof arches 10A and 10B have the same structure, only the first roof arch 10A will be described below, and the first roof arch 10A will be referred to as the "roof arch 10" for the sake of convenience. It shall be stated.

  As shown in FIG. 2, the roof arch 10 is provided with an arch frame 11 having a line symmetric structure around the symmetry axis L. The arch frame 11 is integrally formed by fixing two arch frame parts 11L and 11R to each other by a fixing member 19.

  The arch frame 11 of the roof arch 10 includes a pair of horizontal portions 12 and 12 and a pair of support skeletons 13 and 13. The horizontal portion 12 is connected to the support frame portion 11, and is configured to extend horizontally continuously from the support frame portion 11. The support skeleton 13 is provided in a curved shape at each of left and right corner portions of the arch skeleton 11. In each of the two arch frame portions 11L and 11R, the horizontal portion 12 and the support frame portion 13 are integrally formed of a resin material.

  As shown in FIG. 3, the roof arch 10 is provided with energy absorbing portions 16 at each of the left and right corner portions. The energy absorbing portion 16 is provided so as to be plastically deformable on the outer surface 13 a of the support frame portion 13 of the arch frame 11 in order to absorb the energy at the initial stage of the collision.

  The energy absorbing portion 16 is composed of a plurality of box structures 17 each having a hollow portion 17a. A plurality (five in FIG. 3) of the box structures 17 are arranged along the curved shape of the support frame portion 13 of the arch frame 11. That is, five box structures 17 are arranged side by side in the bending direction D of the support frame portion 13. The energy absorbing portion 16 is configured to absorb energy at the initial stage of the collision by crushing and plastic deformation of the five box structures 17 at the time of a vehicle collision. For this reason, each box structure 17 is deformed so that the whole or a part does not return to the original shape even when the load is removed.

  The box structure 17 of the energy absorbing portion 16 is made of a resin material of a type different from that of the arch frame 11, and is integrally molded with the support frame portion 13 of the arch frame 11. In this case, the roof arch 10 is configured as a resin molded portion in which the support frame portion 13 of the arch frame 11 and the energy absorbing portion 16 are integrally formed of a resin material.

  As a material of the box structure 17, it is preferable to use a resin material which is easily plastically deformed. As an example of this resin material, resin with which polycarbonate (PC resin) and polybutylene terephthalate (PBT resin) were blended is mentioned.

  On the other hand, it is preferable to use, as a material of the arch frame 11, a resin material which is high in rigidity and strength, and which is sticky against deformation. An example of this resin material is a polyamide synthetic resin containing long glass fibers.

  The support frame portion 13 of the arch frame 11 is configured to exceed the box structure 17 of the energy absorbing portion 16 in terms of both strength and rigidity. For this reason, the support frame portion 13 hardly deforms while the box structure 17 is plastically deformed. The support frame portion 13 elastically deforms according to a load received from the box structure 17 after the box structure 17 is plastically deformed. That is, when the load is removed, the support skeleton 13 is deformed so that all or a part thereof returns to a shape close to the original shape. The support frame portion 13 is constituted by a rib structure 14.

  The rib structure 14 includes a first plate portion 14a and a second plate portion 14b which are disposed apart from each other in the collision load input direction C, and an intermediate portion between the first plate portion 14a and the second plate portion 14b. And a plurality of mounted ribs 14c. In this case, the dimension of the rib 14c in the front-rear direction Y (see FIG. 2) is the rib length.

  The rib structure 14 includes a cross rib 15 formed by two ribs 14 c and 14 c intersecting with each other among the plurality of ribs 14 c. The cross rib 15 is effective to increase the strength and the rigidity. In addition, a hollow portion 18 is provided between the adjacent ribs 14c and 14c. The hollow portion 18 is effective to reduce the weight of the support frame portion 13.

  The rib structure 14 extends continuously from the support frame portion 13 to the horizontal portion 12. That is, the arch frame 11 includes a plurality of cross ribs 15 not only on the support frame portion 13 but also on the horizontal portion 12. Therefore, the strength and the rigidity of the entire arch skeleton 11 can be enhanced, and the weight of the arch skeleton 11 can be reduced.

  Here, the operation of the roof arch 10 when the above bus vehicle rolls over and collides with the ground will be described with reference to FIGS. 4 to 6. Such a form of collision is also called "rollover collision".

  As shown in FIG. 4, the corner portion of the roof arch 10 collides with the ground G when the bus vehicle rolls over. The collision load generated at this time is inputted to the corner portion of the roof arch 10, that is, the five box structures 17 of the energy absorbing portion 16 through the roof panel 2.

  As shown in FIG. 5, each box structure 17 is crushed toward the support frame portion 13 by the collision load and is plastically deformed. Then, the box structure 17 absorbs the energy at the initial stage of the collision due to the plastic deformation. On the other hand, the support frame portion 13 having relatively high strength and rigidity supports each box structure 17 so as to be plastically deformable with almost no deformation of itself.

  When the box structure 17 collapses, the box structure 17 is supported by the adjacent box structures 17 so as not to fall sideways. For this reason, each box structure 17 will be crushed generally along the collision load input direction C, and the efficiency of energy absorption is good.

  As shown in FIG. 6, after each box structure 17 is plastically deformed until it almost collapses and finally broken, the support skeleton 13 takes this energy absorbing portion 16 according to the load received from the energy absorbing portion 16. It is displaced while being elastically deformed to the indoor side integrally. At this time, it is preferable that the support frame portion 13 be configured such that the load received from the energy absorbing portion 16 hardly changes in the elastic deformation region.

  Note that each box structure 17 of the energy absorbing portion 16 is deformed so as to be accompanied by a failure such as a crack or a break in its entirety or a portion, in addition to the entire or a portion being plastically deformed by an impact load Alternatively, it may be deformed to a failure after plastic deformation of a part. Also by such deformation, the energy absorbing portion 16 can absorb the energy at the initial stage of the collision.

  On the other hand, in addition to the elastic deformation of all or part of the supporting frame part 13 due to the load received from the energy absorbing part 16, the whole or part is plastically deformed, or the whole or part is broken like a crack or a break. Or plastic deformation of the whole or a part thereof to cause failure. The energy absorbing portion 16 can be supported also by such a deformation.

  Here, the correlation between the load F and the displacement S which the roof arch 10 receives at the time of the above-mentioned collision will be described with reference to FIG.

  In FIG. 7, a diagram showing the above correlation in the case of the first embodiment is represented by a solid line, and a diagram showing the above correlation in the comparative example is represented by a dashed line. The comparative example is an example in which a portion such as the energy absorbing portion 16 is not provided at the corner portion of the roof arch, and the corner portion is formed by a metal pipe structure.

  In the case of the comparative example, the roof arch is reinforced at the entire corner portion, and the load F received at the initial stage of the collision rises sharply to Fc. Then, the load F which a corner part receives continues to fall by the buckling of a corner part. Then, when the corner portion is displaced until the target stroke amount is reached (when the displacement S becomes Sb), the load F received by the corner portion decreases to Fa. This comparative example is premised on the structure which reinforces the whole corner part, and is disadvantageous about weight reduction of a roof arch.

  On the other hand, in the case of the first embodiment, the diagram showing the correlation between the load F and the displacement S can be divided into the A region and the B region.

  Here, the A region is a region where the box structure 17 of the energy absorbing portion 16 absorbs the energy at the initial stage of the collision due to its plastic deformation (see the states of FIGS. 4 to 6). In the A region, the box structure 17 of the energy absorbing portion 16 is plastically deformed until the received load F reaches Fb at the displacement Sa.

  On the other hand, the B region is a region where the support frame portion 13 absorbs energy at the initial stage of collision by elastically deforming while receiving a load from the energy absorbing portion 16 after almost plastic deformation. In the B region, the support frame portion 13 is displaced from the displacement Sa to the displacement Sb with almost no fluctuation of the received load F from Fb.

  Thereby, the load F at the initial stage of the collision can be significantly reduced as compared with the comparative example, and the load F at the late stage of the collision can be increased as compared to the comparative example. At this time, it is preferable that the energy difference Ea for the comparative example at the early stage of the collision and the energy difference Eb for the comparative example at the late stage of the collision coincide with each other. Thereby, the energy absorption amount (consumption amount) equivalent to the case of the comparative example can be secured.

  According to the first embodiment described above, the following effects can be obtained.

  According to the above-described roof structure 1, a collision load initially acts on the energy absorbing portions 16 (box structure 17) at the left and right corner portions of the roof arch 10 at the time of a vehicle collision. At this time, the energy absorbing portion 16 can absorb energy at the initial stage of the collision by plastically deforming under the collision load. In addition, the support frame portion 13 of the arch frame 11 can support the energy absorbing portion 16 at the time of plastic deformation.

  In this case, there is no need to reinforce the energy absorbing portion 16 in order to counter the collision load, and while reducing the weight thereof, the cabins at the left and right corner portions of the roof arch 10 by reinforcing only the support frame portion 13 The amount of displacement in the direction (stroke amount) can be suppressed within the target value. As a result, it is possible to reduce the weight of the roof arch 10 and to secure a cabin space at the time of a vehicle collision. Further, by reducing the weight of the roof arch 10, the fuel efficiency is improved and the operability of the vehicle is improved.

  According to the above-described roof structure 1, the support frame portion 13 exceeds the energy absorbing portion 16 in both strength and rigidity, and elastically deforms according to the load received from the energy absorbing portion 16 which is plastically deformed. After plastic deformation, the load received by the support frame portion 13 from the energy absorbing portion 16 can be made to hardly fluctuate in the elastic deformation region.

  According to the above-described roof structure 1, by using the box structure 17 that is easily plastically deformed as the energy absorbing portion 16, the load that the energy absorbing portion 16 receives at the initial stage of the collision can be suppressed low.

  According to the above-described roof structure 1, by arranging a plurality of box structures 17 along the curved shape of the support frame portion 13, each box structure 17 is plastically deformed in the direction away from the collision load input direction C. It becomes possible to prevent that the adjacent box structure 17 supports. Further, a wide range along the curved shape of the support skeleton 13 can be used for energy absorption at the initial stage of the collision.

  According to the above-described roof structure 1, by forming the support frame portion 13 using the rib structure 14 composed of the plurality of ribs 14 c, the weight of the support frame portion 13 can be reduced and then reinforced. In particular, since the rib structure 14 includes the cross ribs 15, the support skeleton 13 can be reinforced to a desired level by a small number of ribs 14c.

  According to the above-described roof structure 1, both the horizontal portion 12 and the support frame portion 13 of the roof arch 10 can be reinforced by the rib structure 14.

  According to the above-described roof structure 1, the roof arch 10 is configured as a resin molded portion in which the support frame portion 13 and the box structure 17 are integrally formed of a resin material, and weight reduction of the roof arch 10 is achieved. It is effective for

  Hereinafter, other embodiments relating to the above-described first embodiment will be described with reference to the drawings. In the other embodiments, the same elements as the elements of the first embodiment are denoted by the same reference numerals, and the description of the same elements is omitted.

Second Embodiment
As shown in FIG. 8, the roof arch 110 constituting the roof structure 101 of the second embodiment differs from the first embodiment only in the rib structure 114. That is, in the rib structure 114, the plurality of ribs 114c interposed between the first plate portion 114a and the second plate portion 114b are arranged substantially parallel to the bending direction D of the support frame portion 13. Is configured. In this case, the rib 114c is configured such that the dimension in the front-rear direction Y is the rib length, the dimension in the bending direction D of the support frame portion 13 is the rib thickness, and the dimension in the collision load input direction C is the rib height. ing.
The other configuration is the same as that of the first embodiment.

According to the roof structure 101 of the second embodiment, the rib structure 114 different from the rib structure 14 of the first embodiment can be realized, and in particular, the configuration of the rib structure 114 can be simplified.
Other effects and effects similar to those of the first embodiment are achieved.

  As a modification related to the second embodiment, an embodiment in which a part of the plurality of ribs 114c constituting the rib structure 114 is replaced by the cross rib 15 constituting the rib structure 14 of the first embodiment is adopted. It can also be done.

(Embodiment 3)
As shown in FIG. 9, the roof arch 210 that constitutes the roof structure 201 of the third embodiment differs from the first embodiment only in the rib structure 214. That is, in the rib structure 214, the plurality of ribs 214c interposed between the first plate portion 214a and the second plate portion 214b is configured to be disposed substantially in parallel with the longitudinal direction Y. . In this case, the rib 214c is configured such that the dimension in the bending direction D of the support frame portion 13 is the rib length, the dimension in the front-rear direction Y is the rib thickness, and the dimension in the collision load input direction C is the rib height. ing.
The other configuration is the same as that of the first embodiment.

According to the roof structure 201 of the third embodiment, a rib structure 214 different from the rib structure 14 of the first embodiment can be realized.
Other effects and effects similar to those of the first embodiment are achieved.

The present invention is not limited to the above-described embodiment, and various applications and modifications can be considered without departing from the object of the present invention. For example, the following embodiments to which this embodiment is applied can be implemented.

  In the above embodiment, the case where two of the support skeleton 13 and the energy absorbing part 16 are arranged in a stack in the collision load input direction C is exemplified, but one or more other in addition to these two may be exemplified. The members may be arranged in a stack.

  Although the above-mentioned embodiment illustrated about the case where energy absorption part 16 was constituted by box structure 17, if energy absorption performance similar to box structure 17 can be exhibited, it replaces with box structure 17, A member having a shape or a structure different from that of the box structure 17 may be employed.

  Although the above embodiment exemplifies the case where the number of box structures 17 is five, the number of box structures 17 is not limited to this and may be plural other than five. Or may be one.

  In the above-mentioned embodiment, although the case where support skeleton part 13 and energy absorption part 16 were formed in one is illustrated, support skeleton part 13 and energy absorption part 16 which are mutually different members may be joined. Similarly, in the arch frame 11, although the case where the horizontal portion 12 and the support frame portion 13 are integrally formed is illustrated, the horizontal portion 12 and the support frame portion 13 which are separate members may be joined.

  Although the above-mentioned embodiment illustrated about a case where both horizontal part 12 and support frame part 13 have rib structure, it replaces with this, and only either one of horizontal part 12 and support frame part 13 rib structure It is also possible to adopt an embodiment comprising

  Although the above-mentioned embodiment illustrated about a case where arch frame 11 and energy absorption part 16 consist of resin materials of different kinds, it replaces with this, arch skeleton 11 and energy absorption part 16 consist of resin materials of the same kind, It is also good. Further, at least one of the arch frame 11 and the energy absorbing portion 16 may be made of a material other than a resin material, for example, a metal material.

  Although the above-mentioned embodiment illustrated about the roof structure applied to a rollover collision when a vehicle rolls over, this roof structure is applicable also to the collision of forms other than a rollover collision.

  Although the above-mentioned embodiment indicated about the roof structure of a bus vehicle, this roof structure can also be applied to the roof structure of other vehicles other than a bus. Other vehicles include, for example, trucks, small cars, and mini cars.

1,101,201 Vehicle roof structure (roof structure)
DESCRIPTION OF SYMBOLS 10, 10A, 10B, 110, 210 Roof arch 11, 11L, 11R Arch frame 12 Horizontal part 13 Support frame 13a Outer surface 14, 114, 214 Rib structure 14a, 114a, 214a 1st plate part 14b, 114b, 214b Second plate portion 14c, 114c, 214c Rib 15 Cross rib 16 Energy absorbing portion 17 Box structure 17a Hollow part X Vehicle width direction

Claims (8)

A vehicle roof structure having a roof arch extending along a vehicle width direction, comprising:
The roof arch includes a support frame portion provided in a curved shape at each of left and right corner portions, and an energy absorbing portion provided on an outer surface of the support frame portion so as to be able to absorb energy at the initial stage of collision. , A vehicle roof structure.   The vehicle roof structure according to claim 1, wherein the support frame portion is configured to elastically deform in accordance with a load received from the deformed energy absorbing portion in both strength and rigidity over the energy absorbing portion.   The vehicle roof according to claim 1 or 2, wherein said energy absorbing portion comprises a box structure having a hollow portion and is configured to absorb said energy by crushing and plastic deformation of said box structure. Construction.   The vehicle roof structure according to claim 3, wherein a plurality of the box structures are arranged along the curved shape of the support frame portion.   The support frame portion includes a plurality of first plate portions and a second plate portion spaced apart from each other in a collision load input direction, and a plurality of the support frame portions interposed between the first plate portion and the second plate portion. The vehicle roof structure according to any one of claims 1 to 4, which is constituted by a rib structure having a rib.   The vehicle roof structure according to claim 5, wherein the plurality of ribs include a cross rib consisting of two ribs intersecting each other.   The vehicle roof structure according to claim 5 or 6, wherein the roof arch comprises a horizontal portion continuously extending horizontally to the support frame portion, and the horizontal portion is constituted by the rib structure.   The vehicle roof structure according to any one of claims 1 to 7, wherein the roof arch is configured as a resin molded portion in which the support frame portion and the energy absorbing portion are integrally formed of a resin material.

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