Vehicle shock absorbing device

Abstract

To exert desired performance with respect to input from an oblique direction.SOLUTION: An impact absorbing device 1 of a vehicle comprises: a buffer mechanism 5, provided at a front end of a vehicle body 3, which contracts in a longitudinal direction of the vehicle to absorb collision energy; a bumper 6 arranged in front of the buffer mechanism separately therefrom; a push rod 7 extending in the longitudinal direction of the vehicle from the buffer mechanism to the bumper; and a rotary link mechanism 8, arranged between the buffer mechanism and the bumper, which converts force in an oblique direction inputted to the bumper to force in the longitudinal direction, and transmits the force to the buffer mechanism.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to vehicle impact absorbing devices, and more particularly to devices for absorbing crash energy during a vehicle collision. [Background technology]

[0002] As an example of this type of device, Patent Document 1 discloses a device in which a plurality of cylindrical bodies are fixed in a nested manner so as to be contractible in the longitudinal direction of the vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-222035 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the device of Patent Document 1 has a drawback in that when it receives an input from an oblique direction, the sliding portion of the cylindrical body is seized, making it difficult to achieve the desired performance.

[0005] The present disclosure has been made in consideration of the above circumstances, and has an object to provide an impact absorbing device for a vehicle that can exhibit desired performance against an input from an oblique direction. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, a shock absorbing mechanism that is provided at a front end or a rear end of a vehicle body and absorbs collision energy by contracting in a front-rear direction of the vehicle; a bumper disposed in front of or behind the shock absorbing mechanism and spaced apart from the shock absorbing mechanism; a push rod extending in a vehicle front-rear direction from the shock absorbing mechanism to the bumper; a rotation link mechanism that is disposed between the shock absorber and the bumper, and that converts an oblique force input to the bumper into a forward / rearward force and transmits the force to the shock absorber; The present invention provides an impact absorbing device for a vehicle, comprising:

[0007] Preferably, the rotary link mechanism comprises: A rotating body rotatably supported on the vehicle body; an output arm fixed to the rotor and connected to the buffer mechanism; An input arm fixed to the rotating body; an inclined push rod extending obliquely with respect to a vehicle front-rear direction and transmitting an oblique force input to the bumper to the input arm; Equipped with.

[0008] Preferably, the inclined push rod includes a right inclined push rod corresponding to an input from the right oblique front or right oblique rear, and a left inclined push rod corresponding to an input from the left oblique front or left oblique rear, The input arms include a right input arm corresponding to the right tilt push rod and a left input arm corresponding to the left tilt push rod.

[0009] Preferably, one end of the tilt push rod is pivotally connected to the bumper, and the other end is releasably engaged with the tip of the input arm.

[0010] Preferably, one of the other end of the inclined push rod and the tip of the input arm is removably inserted into the bottomed hole of the other.

[0011] Preferably, the buffer mechanism includes a plurality of cylindrical bodies arranged in a nested manner so as to be contractible in a vehicle longitudinal direction, Two adjacent cylindrical bodies are fixed to each other, and the rearmost or frontmost cylindrical body and the vehicle body are fixed to each other.

[0012] Preferably, a plurality of fixing points for fixing the cylindrical body to another cylindrical body or the vehicle body are provided in a front-rear direction of the vehicle, The fixing strength is different among the plurality of fixing points.

[0013] Preferably, the cylindrical body is fixed to another cylindrical body or to the vehicle body with a gap therebetween.

[0014] Preferably, the cylindrical body has a tapered shape in a portion rearward or forward of the fixing point.

[0015] Preferably, the cylindrical body is fixed to another cylindrical body or to the vehicle body via a spacer. Effect of the Invention

[0016] According to the present disclosure, it is possible to achieve desired performance with respect to input from an oblique direction. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a schematic plan view showing a configuration of the present embodiment. [Diagram 2] FIG. 2 is a schematic perspective view showing the impact absorbing device. [Diagram 3] FIG. 2 is a plan view showing the impact absorbing device. [Figure 4] FIG. [Diagram 5] 4 is a cross-sectional view taken along line VV of FIG. 3, showing an engaged state between the push rod and the engaging portion. FIG. [Figure 6] FIG. [Figure 7] FIG. 11 is a plan view showing the operation at the time of a right oblique collision. [Figure 8] FIG. 11 is a plan view showing the operation at the time of a left diagonal collision. [Figure 9] FIG. 11 is a vertical sectional side view showing a buffer mechanism of a first modified example. [Figure 10] FIG. 11 is a vertical sectional side view showing a buffer mechanism of a second modified example. [Figure 11]FIG. 13 is a cross-sectional view showing an engaged state between an inclined push rod and an engaging portion in a third modified example. [Figure 12] FIG. 13 is a plan view showing a buffer mechanism of a fourth modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. Note that the present disclosure is not limited to the following embodiments.

[0019] Fig. 1 is a schematic plan view showing the configuration of this embodiment. The impact absorbing device 1 is disposed at the front end of the vehicle and is configured to absorb impact from the front of the vehicle. The vehicle in this embodiment is a truck, but the type of vehicle is arbitrary, and may be, for example, a passenger car. The vehicle has a ladder frame 2 that forms the vehicle body. The ladder frame 2 has left and right side members 3 and multiple (only one is shown) cross members 4 that connect these side members.

[0020] The impact absorbing device 1 comprises a buffer mechanism 5 that is provided at the front end of the side member 3 and absorbs collision energy by contracting in the fore-and-aft direction of the vehicle, a bumper 6 that is arranged at a distance in front of the buffer mechanism 5, a push rod 7 that extends in the fore-and-aft direction of the vehicle from the buffer mechanism 5 to the bumper 6, and a rotating link mechanism 8 that is arranged between the buffer mechanism 5 and the bumper 6 and converts the diagonal force input to the bumper 6 into a fore-and-aft force and transmits it to the buffer mechanism 5.

[0021] The impact absorbing device 1 is provided for each of the left and right side members 3. The bumper 6 is common to both the left and right side members 3 and extends across the entire width of the vehicle. In contrast, the elements other than the bumper 6, i.e., the buffer mechanism 5, the push rod 7 and the rotary link mechanism 8, are provided individually for the left and right side members 3. As the configurations of these elements are the same on the left and right, the following description will mainly focus on the right side.

[0022] Fig. 2 is a schematic perspective view showing the impact absorbing device 1, and Fig. 3 is a plan view showing the impact absorbing device 1. Note that Fig. 2 is merely a schematic view, and Fig. 3 is a more accurate view.

[0023] The side member 3 of this embodiment has a rectangular closed cross-sectional shape in a front view, but may have an open cross-sectional shape. A base end (rear end) of the shock absorbing mechanism 5 is fixed to the side member 3.

[0024] 4, the shock absorbing mechanism 5 extends in the front-rear direction coaxially with the side member 3. The shock absorbing mechanism 5 includes a plurality of tubular bodies 9 arranged in a nested manner so as to be contractible in the front-rear direction of the vehicle. Two adjacent tubular bodies 9 are fixed to each other, and the rearmost tubular body 9 and the side member 3 are also fixed to each other.

[0025] In the present embodiment, the shock absorbing mechanism 5 includes three cylindrical bodies 9 arranged in order from the front, that is, a first cylindrical body 9A at the front end, a second cylindrical body 9B in the middle, and a third cylindrical body 9C at the rear end. The three cylindrical bodies 9 are each open at the front and rear ends, have a rectangular shape similar to the side member 3 in a front view, and have a constant cross-sectional shape in the front-rear direction, with the outer shape being smaller toward the front. The base ends (rear ends) of the three cylindrical bodies 9 are slidably inserted into the tip ends (front ends) of the side member 3 or cylindrical bodies 9 adjacent to the rear side, and are fixed by bolts 10 and nuts 11. The bolts 10 are inserted from the outside into insertion holes 13 provided in the cylindrical bodies 9 and the side member 3. The nuts 11 are tightened to the bolts 10 inside the cylindrical bodies 9.

[0026] If the bolts 10 are broken or sheared during a vehicle collision and come loose, the three tubular bodies 9 slide rearward within the adjacent tubular body 9 on the rear side or the side member 3. This causes the shock absorbing mechanism 5 to contract and absorb the collision energy.

[0027] A plurality of (three in this embodiment) fixing points 12 using bolts 10 and nuts 11 are provided in the vehicle front-rear direction. That is, a first fixing point 12A at the front end for fixing the first cylindrical body 9A and the second cylindrical body 9B, a second fixing point 12B in the middle for fixing the second cylindrical body 9B and the third cylindrical body 9C, and a third fixing point 12C at the rear end for fixing the third cylindrical body 9C and the side member 3 are provided. At each fixing point 12, fixing is performed by the bolts 10 and nuts 11 on four surfaces of the cylindrical body 9, namely, top, bottom, left and right.

[0028] In this embodiment, the fixing strength is different at these fixing points 12, with the fixing strength being higher at the fixing points 12 located further back. Specifically, the number of bolts 10 used for fixing is increased. In the illustrated example, the number of bolts at the first fixing point 12A is 1 bolt x 4 surfaces = 4. The number of bolts at the second fixing point 12A is 2 bolts x 4 surfaces = 8. The number of bolts at the third fixing point 12C is 3 bolts x 4 surfaces = 12. Note that the method of changing the fixing strength is arbitrary and is not limited to this method.

[0029] A front end plate 14 that closes the open portion is provided on the front end surface of the first cylindrical body 9A. This front end plate 14 is the part that receives an input from the front in the shock absorbing mechanism 5. A pair of upper and lower mounting plates 16 are integrally provided on the front surface of the front end plate 14.

[0030] As shown in Figs. 1 to 3, as is well known, the bumper 6 is located at the front end of the lower part of the vehicle and is the first part to receive a collision force. The bumper 6 is fixed to the side member 3 by a bracket (not shown). On the back surface (rear surface) of the bumper 6, three seats 15, 15R, 15L are provided at approximately equal intervals in the left-right direction for mounting a push rod described later, etc. The seat 15 located in the center or center in the left-right direction (vehicle width direction) is located at approximately the same position as the buffer mechanism 5 in the left-right direction. In contrast, the seat 15R located on the right side in the left-right direction is located to the right of the buffer mechanism 5 in the left-right direction. The seat 15L located on the left side in the left-right direction is located to the left of the buffer mechanism 5 in the left-right direction.

[0031] The push rod 7 is a shaft-like member with a square cross section that extends in the front-rear direction directly in front of the buffer mechanism 5. The base end or rear end of the push rod 7 is disposed between upper and lower mounting plates 16 and is rotatably connected to the mounting plates 16 by a rotation shaft 17, which is a vertical shaft extending in the up-down direction. An enlarged flange portion 18 is integrally provided at the tip or front end of the push rod 7, and this flange portion 18 abuts against a seat portion 15 located directly in front of the buffer mechanism 5.

[0032] The rotating link mechanism 8 includes a rotating body 20 rotatably supported on the side member 3, an output arm 21 fixed to the rotating body 20 and connected to the buffer mechanism 9, an input arm 22 fixed to the rotating body 20, and an inclined push rod 23 extending obliquely with respect to the front-to-rear direction and transmitting the oblique force input to the bumper 6 to the input arm 22.

[0033] In this embodiment, there are two types of inclined push rods 23 and input arms 22, one for the right side and one for the left side. That is, the inclined push rods 23 include a right inclined push rod 23R corresponding to an input from the diagonal front right, and a left inclined push rod 23L corresponding to an input from the diagonal front left. The input arm 22 includes a right input arm 22R corresponding to the right inclined push rod 23R, and a left input arm 22L corresponding to the left inclined push rod 23L.

[0034] A pair of upper and lower support brackets 24 are fixed to the side member 3. The base ends (rear ends) of these support brackets 24 are fixed to the upper and lower surfaces of the side member 3 by welding, bolting, or the like. The support brackets 24 extend diagonally forward and left from the base ends. The tip ends (front ends) of the support brackets 24 are located at a position in the front-rear direction substantially equal to the front end of the second cylindrical body 9B and to the left of the front end of the second cylindrical body 9B. The rotating body 20 is rotatably supported at the tip ends of the upper and lower support brackets 24.

[0035] The rotating body 20 is formed into a cylindrical shape extending in the vertical direction. A rotating shaft 25, which is a vertical shaft, is inserted into the rotating body 20 so as to be slidable and rotatable. The rotating shaft 25 is supported by upper and lower support brackets 24. This allows the rotating body 20 to rotate around the rotating shaft 25, and is rotatably supported by the side member 3 via the rotating shaft 25 and the support brackets 24.

[0036] A base end of the output arm 21 is fixed to the outer periphery of the rotor 20. A tip end of the output arm 21 is rotatably connected to the mounting plate 16 by the rotary shaft 17. In a plan view as shown in Fig. 3, the phase of the output arm 21 about the center O of the rotary shaft 25 is defined as a reference phase θ0.

[0037] The right input arm 22R is positioned above the output arm 21. A base end of the right input arm 22R is fixed to the outer periphery of the rotor 20. A phase θR of the right input arm 22R is shifted by a predetermined phase ΔθR (e.g., about 45°) in the clockwise direction (predetermined rotation direction) with respect to a reference phase θ0. An engagement portion 26 for engaging with the tip end of the right inclined push rod 23R, i.e., a right engagement portion 26R, is provided at the tip end of the right input arm 22R.

[0038] The right-side inclined push rod 23R is a shaft-like member having a rectangular cross section. A base end of the right-side inclined push rod 23R is rotatably connected to the right-side seat portion 15R of the bumper 6 by a rotation shaft 27R, which is a vertical shaft. The right-side inclined push rod 23R extends obliquely rearward and left from the base end, and a tip end of the right-side inclined push rod 23R is engaged with a right-side engagement portion 26R of the right-side inclined push rod 23R. The longitudinal direction of the right-side inclined push rod 23R intersects with the longitudinal direction of the right-side input arm 22R at a predetermined angle that is perpendicular or approximately perpendicular, or as close to perpendicular as possible.

[0039] 5 shows the engagement state between the tip of the right-side oblique pushrod 23R and the right-side engagement part 26R. The right-side engagement part 26R is a block-shaped member larger in cross section than the right-side oblique pushrod 23R, and has a bottomed hole 28 into which the tip of the right-side oblique pushrod 23R is inserted. The tip of the right-side oblique pushrod 23R is inserted coaxially and retractably into the bottomed hole 28 with a predetermined clearance. The cross-sectional shape of the bottomed hole 28 is a rectangle similar to and slightly larger than the cross-sectional shape of the right-side oblique pushrod 23R.

[0040] When the right-side oblique push rod 23R is pushed axially rearward during a vehicle collision, the right-side oblique push rod 23R presses the bottom surface 28A of the bottomed hole 28, and presses the right-side input arm 22R to rotate the rotating body 20. Furthermore, when the right-side engagement portion 26R separates from the right-side oblique push rod 23R during a vehicle collision, the right-side oblique push rod 23R is pulled out of the bottomed hole 28 and becomes free (this will be described in detail later).

[0041] The left input arm 22L and the left inclined push rod 23L are configured in a similar manner. The left input arm 22L is positioned below the output arm 21. The base end of the left input arm 22L is fixed to the outer periphery of the rotor 20. The phase θL of the left input arm 22L is shifted counterclockwise from the reference phase θ0 by a predetermined phase ΔθL (e.g., about 45°). This predetermined phase ΔθL is approximately equal to the predetermined phase θR. Therefore, the right input arm 22R and the left input arm 22L are disposed approximately axially symmetrically with the output arm 21 as the boundary. A left engagement portion 26L is also provided at the tip of the left input arm 22L.

[0042] The left inclined push rod 23L is also a shaft-like member having a rectangular cross section. However, the left inclined push rod 23L is shorter than the right inclined push rod 23L. The base end of the left inclined push rod 23L is rotatably connected to the left seat part 15L of the bumper 6 by a rotation shaft 27L, which is a vertical shaft. The left inclined push rod 23L extends obliquely rearward and rightward from the base end, and its tip end is engaged with the left engagement part 26L of the left input arm 22L. The longitudinal direction of the left inclined push rod 23L intersects with the longitudinal direction of the left input arm 22L at a predetermined angle that is perpendicular or approximately perpendicular, or as close to perpendicular as possible.

[0043] The method of engaging the tip end of the left oblique push rod 23L with the left engagement portion 26L is the same as that described above. The tip end of the left oblique push rod 23L is inserted into the bottomed hole 28 of the left engagement portion 26L in a removable manner. When the left oblique push rod 23L is pushed axially rearward during a vehicle collision, the left oblique push rod 23L pushes the bottom surface 28A of the bottomed hole 28, and pushes the left input arm 22L to rotate the rotating body 20.

[0044] Next, the effects of this embodiment will be described.

[0045] Fig. 6 shows the state when a vehicle is hit head-on from the front. At this time, a collision force F parallel to the front-rear direction from the front to the rear is input to the bumper 6. The bumper 6 moves straight back from the position before the collision (shown by the imaginary line a) while maintaining a parallel state.

[0046] When a collision force F is input to the bumper 6, this force F pushes the center push rod 7 rearward along its longitudinal direction. Then, the force F is transmitted to the front end plate 14 of the shock absorber mechanism 5 through the pivot shaft 17 and the mounting plate 16 in that order. This force F pushes the shock absorber mechanism 5 rearward and contracts it. At this time, the bolts 10 forming the fixing parts of the shock absorber mechanism 5 are shear-broken, and the three tubular bodies 9 move back and slide into the adjacent tubular body 9 or the side member 3 at the rear. This absorbs and mitigates the collision energy at the initial stage of the collision, minimizing the shock to the occupants and the deformation of the side member 3. In the final state shown in the figure, all three tubular bodies 9 are inserted into the side member 3.

[0047] At this time, in the rotary link mechanism 8, as the buffer mechanism 5 contracts, i.e., as the first cylindrical body 9A retreats, the output arm 21 connected thereto and, in turn, the rotor 20 rotates clockwise. Then, the right input arm 22R and the left input arm 22L also rotate clockwise. Then, the right engaging portion 26R and the left engaging portion 26 of the right input arm 22R and the left input arm 22L are pulled away from the right inclined push rod 23R and the left inclined push rod 23L, respectively, and both are released from the engaged state. That is, the right inclined push rod 23R and the left inclined push rod 23L are pulled out from the bottomed holes 28 of the right engaging portion 26R and the left engaging portion 26, respectively. This allows the rotor 20 to rotate and the buffer mechanism 5 to contract smoothly without any hindrance.

[0048] Next, a case where the vehicle is hit diagonally from the front will be described.

[0049] 7 shows a state in which a vehicle is hit diagonally from the front right. At this time, a collision force F is input from the front right to the bumper 6. The bumper 6 moves backward while tilting diagonally to the front right from the position before the collision (shown by the imaginary line a).

[0050] When a collision force F is input to the bumper 6, this force F pushes the right inclined push rod 23R diagonally rearward to the left along its longitudinal direction. The right inclined push rod 23R pushes the bottom surface 28A of the bottomed hole 28 of the right engagement portion 26R, and the force F is transmitted to the right input arm 22R. The force F rotates the right input arm 22R and the rotating body 20 clockwise. This causes the output arm 21 to also rotate in the same direction, pushing the front end plate 14 of the shock absorber mechanism 5 straight rearward in the same manner as above. This causes the shock absorber mechanism 5 to contract in the same manner as above.

[0051] In this way, the impact force F from the right oblique front is converted into a rearward force in the front-rear direction by the rotary link mechanism 8, and the shock absorbing mechanism 5 can be contracted in the same manner as in the case of a head-on collision.

[0052] If there were no rotary link mechanism 8 as in this embodiment, the impact force F from the right diagonal front would be transmitted in the same direction to the front end (front end plate 14) of the shock absorber mechanism 5, causing the shock absorber mechanism 5 to contract. However, at this time, the cylindrical body 9 would be slightly tilted and would slide in while strongly contacting the inner surface portion (specifically the left inner surface portion) of the adjacent cylindrical body 9 or side member 3 at the rear. This would cause galling, making it difficult to slide the cylindrical body 9 smoothly as planned. Furthermore, the galling would weaken the shear force on the bolt 10, and there is a possibility that the bolt 10 would not be shear-broken as planned, which could reduce the shock absorber performance of the shock absorber mechanism 5.

[0053] This embodiment solves these problems by allowing the cylindrical body 9 to be pushed straight backward, thereby preventing the occurrence of galling and enabling the desired performance to be exhibited with respect to input from an oblique direction.

[0054] Meanwhile, the left input arm 22L also rotates due to the rotation of the rotating body 20, and the left engagement portion 26 is pulled away from the left inclined push rod 23L, and the left inclined push rod 23L and the left inclined push rod 23L are disengaged from each other. That is, the left inclined push rod 23L is pulled out of the bottomed hole 28 of the left engagement portion 26. Furthermore, the center push rod 7 is moved straight rearward as the shock absorber mechanism 5 contracts, and is separated from the bumper 6. This operation allows the rotation link mechanism 8 to operate without hindrance.

[0055] The same applies when the vehicle is hit from the left diagonal front. Figure 8 shows the state at this time. A collision force F is input to the bumper 6 from the left diagonal front. The bumper 6 moves backward while tilting diagonally forward to the left from the position before the collision (shown by the imaginary line a).

[0056] When a collision force F is input to the bumper 6, this force F pushes the left inclined push rod 23L diagonally rearward to the right along its longitudinal direction. The left inclined push rod 23L pushes the bottom surface 28A of the bottomed hole 28 of the left engagement portion 26L, and the force F is transmitted to the left input arm 22L. The force F rotates the left input arm 22L and the rotating body 20 clockwise. This causes the output arm 21 to also rotate in the same direction, pushing the front end plate 14 of the shock absorber mechanism 5 straight rearward in the same manner as above. This causes the shock absorber mechanism 5 to contract in the same manner as above.

[0057] In this way, the impact force F from the left diagonal front is converted into a rearward force in the fore-and-aft direction by the rotary link mechanism 8, and the shock absorber mechanism 5 can be contracted in the same way as in the case of a frontal collision. This allows the cylindrical body 9 to be pushed straight backward, suppressing the occurrence of scuffing and providing the desired performance against inputs from diagonal directions.

[0058] Meanwhile, the right input arm 22R also rotates due to the rotation of the rotating body 20, and the right engagement portion 26 is pulled away from the right inclined push rod 23R, and the two are disengaged from each other. That is, the right inclined push rod 23R is pulled out of the bottomed hole 28 of the right engagement portion 26. Furthermore, the center push rod 7 is moved straight rearward as the buffer mechanism 5 contracts, and is separated from the bumper 6. This operation allows the rotation link mechanism 8 to operate without hindrance.

[0059] In this embodiment, the fixing strength is different at three different fixing points 12 in the front-rear direction in the buffer mechanism 5. By changing the fixing strength in this way, the shock absorbing characteristics of the buffer mechanism 5 can be set to an optimum value.

[0060] In this embodiment, the fixing strength is lowered toward the front of the fixing points 12 and higher toward the rear of the fixing points 12. In this way, in the event of a vehicle collision, the fixing can be released first at the first fixing point 12A at the forefront (the bolt 10 is sheared), then the fixing can be released at the second fixing point 12B in the middle, and finally the fixing can be released at the third fixing point 12C at the rearmost end. In other words, the fixing can be released with a time difference starting from the fixing point 12 with the weakest fixing strength. This allows the collision energy to be absorbed quickly at the first release, and the amount of collision energy absorbed can be increased stepwise at the subsequent releases.

[0061] In this embodiment, the same bolts 10 are used, and the fixing strength is changed by changing the number of bolts 10 for each fixing point 12. However, other methods are also possible, and the fixing strength may be changed by changing the outer diameter of the bolts 10.

[0062] The cylindrical body 9 may be fixed by welding, rivets, etc. In this case, the fixing strength may be changed by changing the length of the weld allowance, the number of spots, or the number and outer diameter of the rivets.

[0063] It is preferable to fasten the cylindrical body 9 with bolts rather than welding, because the variation in fastening strength is relatively large when welding is used. Also, the bolts 10 have little variation in mass production, so the fastening strength is less likely to vary, the bolt shear force during shock absorption is easy to calculate, and the optimal number and outer diameter of the bolts 10 are easy to determine.

[0064] The impact absorbing device 1 of this embodiment is provided on each of the left and right side members 3. When a vehicle experiences an offset collision, one of the left and right impact absorbing devices 1 experiences the same impact as a head-on collision, but the other may experience the same impact as an oblique collision. In this case, the other device receives an input in an oblique direction. Therefore, the configuration of this embodiment is considered to be effective against offset collisions as well.

[0065] Next, a modified example will be described. Note that a description of the same parts as in the basic embodiment will be omitted, and the following description will focus mainly on the differences from the basic embodiment.

[0066] (First Modification) In the buffer mechanism 5 of the basic embodiment, as shown in FIG. 4, the cross-sectional shape of the cylindrical body 9 is constant in the longitudinal direction (front-rear direction).

[0067] In contrast, in the buffer mechanism 5 of this modified example, as shown in Fig. 9, the cross-sectional shape of the cylindrical body 9 changes in the longitudinal direction. Specifically, the portion of the cylindrical body 9 rearward from the fixing point 12 (the position where the bolt 10 is inserted) has a tapered shape. The diameter of the cylindrical body 9 decreases toward the rear in the portion rearward from the fixing point 12. In other words, the length of each side of the rectangular cross section decreases toward the rear. The rear portion is then bent toward the central axis of the cylindrical body 9 to have a cross-sectional arc shape as shown in the figure.

[0068] In this modified example, since there is a rotary link mechanism 8, even if there is an input from the diagonal front, this is converted into a rearward force, and the cylindrical body 9 can be pushed straight backward. However, even if a force is applied to the cylindrical body 9 from the diagonal front, this modified example can suppress seizing.

[0069] That is, when a force is applied to the cylindrical body 9 from the oblique front, the cylindrical body 9 tries to slide while tilting slightly. However, because the rear end of the cylindrical body 9 is narrowed, it is possible to prevent the cylindrical body 9 from strongly hitting another cylindrical body 9 adjacent to the rear or the side member 3. As a result, even if a force is applied to the cylindrical body 9 from the oblique front, it is possible to prevent the cylindrical body 9 from seizing and to allow the cylindrical body 9 to slide smoothly, thereby achieving the desired performance.

[0070] In this sense, it is preferable that the tubular body 9 is fixed to another adjacent tubular body 9 or side member 3 at the rear with a gap therebetween. In this modified example, a gap S is provided between a portion of the tubular body 9 rearward of the fixing point 12 and the other adjacent tubular body 9 or side member 3 at the rear. Alternatively, the diameter of the other tubular body 9 or side member 3 may be expanded at a position rearward of the fixing point 12 of the tubular body 9 to form the gap.

[0071] (Second Modification) 10, in the shock absorbing mechanism 5 of this modification, the cylindrical body 9 and another cylindrical body 9 or side member 3 adjacent to it at the rear are fixed with a bolt 10 and a nut 11 with a spacer 29 sandwiched therebetween. As a result, a gap S is formed in the entire longitudinal direction between the cylindrical body 9 and the other cylindrical body 9 or side member 3. The cross-sectional shape of the three cylindrical bodies 9 is constant in the longitudinal direction (front-rear direction).

[0072] The spacer 29 is formed of a washer, which is a general-purpose product, and this allows the gap S to be formed simply and inexpensively.

[0073] The effects of this modification are similar to those of the first modification, that is, even when a force is applied to the cylindrical body 9 from the oblique front, the rear end of the cylindrical body 9 is prevented from being scuffed, and the cylindrical body 9 can be smoothly slid.

[0074] (Third Modification) In the basic embodiment, the tip end of the inclined push rod 23 is simply inserted into the bottomed hole 28 of the engagement portion 26 as shown in FIG.

[0075] In contrast, in this modified example, as shown in FIG. 11, after the tip of the inclined push rod 23 is inserted into the bottomed hole 28 of the engagement portion 26, it is locked to the engagement portion 26 by an easily breakable locking member.

[0076] In this modification, a wire is used as the locking member, more specifically, a split pin 30. The split pin 30 is inserted in a closed state into through holes 31, 32 provided in the tip end portion of the inclined push rod 23 and the engagement portion 26, respectively. Then, both ends of the split pin 30 are opened, and thus the split pin 30 is locked into the through holes 31, 32.

[0077] In the event of a vehicle collision, the rotary link mechanism 8 operates as shown in Figures 6 to 8, and the tip of the inclined push rod 23 is pulled out of the bottomed hole 28 of the engagement portion 26. At this time, the split pin 30 is sheared and broken, allowing the inclined push rod 23 to be pulled out without any hindrance.

[0078] On the other hand, during assembly, the inclined push rod 23 can be held in a locked state in the engagement portion 26, making the assembly work easier. Also, during normal use, the inclined push rod 23 can be prevented from being accidentally pulled out of the engagement portion 26.

[0079] As such a locking member, in addition to the split pin 30, an ordinary wire, a snap pin, etc. can be used.

[0080] (Fourth Modification) In this modification, as shown in Fig. 12, a fluid pressure cylinder, specifically a hydraulic cylinder 33, is used as the shock absorbing mechanism 5. The hydraulic cylinder 33 is fixed inside the side member 3 with its piston rod 34 facing forward. The piston rod 34 protrudes forward from the side member 3, and the front end of the piston rod 34 is connected to the tip of the output arm 21 by a rotating shaft 17 so as to be rotatable.

[0081] When the vehicle collides, the piston rod 34 is pushed backward by the output arm 21 and contracts. At this time, oil passes through an orifice provided in the piston 35 of the hydraulic cylinder 33, generating a damping force, which absorbs the collision energy.

[0082] Although the embodiment of the present disclosure has been described in detail above, various other embodiments and modifications of the present disclosure are possible.

[0083] (1) For example, the shock absorbing device may be disposed at the rear end of the vehicle to absorb shock from the rear of the vehicle. In this case, the configuration of the above embodiment is simply reversed, so no special explanation is required.

[0084] (2) In the above embodiment, the same impact absorbing device 1 is provided for the left and right side members 3. However, symmetrical impact absorbing devices 1 may be provided for the left and right side members 3.

[0085] (3) The configuration of the rotary link mechanism 8 shown in Fig. 3 may be reversed. For example, it is possible to place the rotary body 20 on the right side of the buffer mechanism 5, and to appropriately modify other members accordingly.

[0086] (4) It is possible to change the cross-sectional shape of each member extending in the longitudinal direction. For example, the cross-sectional shapes of the cylindrical body 9, the push rod 7, the inclined push rod 23, and the bottomed hole 28 can be shapes other than a rectangle, such as a circle, an ellipse, etc.

[0087] (5) The base end of the push rod 7 may be fixed to the buffer mechanism 5. The tip of the push rod 7 may be located close to the bumper 6, or may be locked by an easily breakable locking member.

[0088] (6) The pair of the right inclined push rod 23R and the right input arm 22R, or the pair of the left inclined push rod 23L and the left input arm 22L may be omitted from the rotary link mechanism 8 of the above embodiment.

[0089] (7) Contrary to the above embodiment, the tip end portion or the engaging portion 26 of the input arm 22 may be inserted into the bottomed hole of the inclined push rod 23 in a removable manner.

[0090] (8) In the buffer mechanism 5, the way in which the cross-sectional dimensions of the cylindrical body 9 change in the front-rear direction may be changed. In the above embodiment, the cross-sectional dimensions are increased from the front to the rear, but conversely, the cross-sectional dimensions may be decreased from the front to the rear. Also, the cross-sectional dimensions may be changed alternately from the front to the rear, such as small, large, small, large, or more randomly.

[0091] The configurations of the above-mentioned embodiments and modifications can be combined in part or in whole unless there is a particular contradiction. The embodiments of the present disclosure are not limited to the above-mentioned embodiments, and all modifications, applications, and equivalents encompassed within the spirit of the present disclosure as defined by the claims are included in the present disclosure. Therefore, the present disclosure should not be interpreted as being limited, and can be applied to any other technology that falls within the spirit of the present disclosure. [Explanation of symbols]

[0092] 1. Shock absorbing device 2 Ladder frame 3 Side members 5 Buffer mechanism 6 Bumper 7 Pushrod 8 Rotating link mechanism 9 Cylindrical body 12 Fixing point 20 Rotating Body 21 Output arm 22 Input Arm 22R Right side input arm 22L Left input arm 23 Inclined Pushrod 23R Right inclined push rod 23L Left inclined push rod 28 Bottomed hole 29 Spacer S Gap

Claims

1. a shock absorbing mechanism that is provided at a front end or a rear end of a vehicle body and absorbs collision energy by contracting in a front-rear direction of the vehicle; a bumper disposed in front of or behind the shock absorbing mechanism and spaced apart from the shock absorbing mechanism; a push rod extending in a vehicle front-rear direction from the shock absorbing mechanism to the bumper; a rotation link mechanism that is disposed between the shock absorber mechanism and the bumper, and that converts an oblique force input to the bumper into a forward / rearward force and transmits the force to the shock absorber mechanism; An impact absorbing device for a vehicle comprising:

2. The rotation link mechanism includes: A rotating body rotatably supported on the vehicle body; an output arm fixed to the rotor and connected to the buffer mechanism; An input arm fixed to the rotating body; an inclined push rod extending obliquely with respect to a vehicle front-rear direction and transmitting an oblique force input to the bumper to the input arm; Equipped 2. The vehicle shock absorbing device according to claim 1.

3. the inclined push rods include a right inclined push rod corresponding to an input from the right oblique front or right oblique rear, and a left inclined push rod corresponding to an input from the left oblique front or left oblique rear, The input arm includes a right input arm corresponding to the right tilt push rod and a left input arm corresponding to the left tilt push rod.

3. The vehicle shock absorbing device according to claim 2.

4. One end of the tilt push rod is pivotally connected to the bumper, and the other end is releasably engaged with the tip of the input arm.

4. The shock absorbing device for a vehicle according to claim 2 or 3.

5. One of the other end of the inclined push rod and the tip of the input arm is removably inserted into the other bottomed hole.

5. The shock absorbing device for a vehicle according to claim 4.

6. the shock absorbing mechanism includes a plurality of cylindrical bodies arranged in a nested manner so as to be contractible in a vehicle front-rear direction, Two adjacent cylindrical bodies are fixed to each other, and the cylindrical body at the rear end or the front end is fixed to the vehicle body. The shock absorbing device for a vehicle according to any one of claims 1 to 5.

7. A plurality of fixing points for fixing the cylindrical body to another cylindrical body or the vehicle body are provided in the front-rear direction of the vehicle, The fixing strength is different at the multiple fixing points.

7. The shock absorbing device for a vehicle according to claim 6.

8. The cylindrical body is fixed to another cylindrical body or the vehicle body with a gap therebetween.

8. The shock absorbing device for a vehicle according to claim 6 or 7.

9. The cylindrical body has a tapered shape at a portion rearward or forward of the fixing point. The shock absorbing device for a vehicle according to any one of claims 6 to 8.

10. The cylindrical body is fixed to another cylindrical body or the vehicle body via a spacer. The shock absorbing device for a vehicle according to any one of claims 6 to 9.

Images