Vehicle seat

Abstract

To provide a vehicular seat which can inhibit the seat from inclining rearward at the time of a rear collision while inhibiting increase of the weight of the seat.SOLUTION: A vehicular seat includes a link mechanism 6 which may adjust a height of a seat cushion 2. The link mechanism 6 includes: attachment brackets 11 attached to a floor part of a passenger compartment; multiple link arms 12, 13 which link a cushion frame 7 to each attachment bracket 11 so that the cushion frame 7 may move between a first position and a second position, located at the vehicle rear side and lower side relative to the first position, while keeping itself parallel to the attachment bracket 11; and projection parts 17 each formed integrally with the attachment bracket 11, protruding upward from an upper surface of the attachment bracket 11, and having a contact surface 18, which a contacted part 15 forming a part of the cushion frame 7 may contact at the time of a rear collision of a vehicle, at the upper surface side.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a vehicle seat.

Background Art

[0002] Conventionally, there is a seat provided with a link mechanism for adjusting the height of the seat in a vehicle seat. In such a seat, when a following vehicle collides with the rear part of the vehicle, as the seated person relatively moves rearward inside the vehicle due to inertia, the link arm of the link mechanism rotates rearward of the vehicle by the inertial force, and the tilting angle of the link arm toward the rear of the vehicle may increase. At this time, as the tilting angle of the link arm increases, there is a risk that the seat may contact the occupant in the rear seat.

[0003] Therefore, in order to prevent the seat from tilting backward during a rear-end collision of the vehicle, the seat described in Patent Document 1 includes a stop body formed on a seat link (link arm) of the vehicle seat, and a stop element that can come into contact with the stop body when the seat link tilts backward. The stop element is screwed to the upper seat rail at a position on the rear side of the seat link in the upper seat rail. During a rear-end collision of the vehicle, the stop element attached to the upper seat rail comes into contact with the stop body of the seat link, thereby suppressing the backward tilt of the seat during the rear-end collision.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the above-described seat structure, in order to prevent the seat from tilting backward, it is necessary to attach a special member called a stop element to the upper seat rail separately from the link mechanism. Further, this stop element is required to have sufficient strength to withstand the load when it abuts against the stop body on the seat link side during a vehicle collision. For this reason, there is a concern that the weight of the entire seat increases.

[0006] The present invention has been made in view of the above circumstances, and an object thereof is to provide a vehicle seat capable of suppressing the backward tilt of the seat during a rear collision while suppressing an increase in the weight of the seat.

Means for Solving the Problems

[0007] The vehicle seat of the present invention is a vehicle seat including a seat cushion and a link mechanism capable of adjusting the height of the seat cushion, wherein the link mechanism includes a cushion frame that supports the seat cushion and , vehicle a mounting bracket directly or indirectly attached to the floor portion of the room, and a plurality of link arms that link and couple the cushion frame and the mounting bracket so that the cushion frame can move between a first position while maintaining parallelism with the mounting bracket and a second position that is on the rearward and downward side of the vehicle with respect to the first position, and a protrusion integrally formed on the mounting bracket and protruding upward from the upper surface of the mounting bracket, the protrusion having a contact surface on the upper surface side against which a contact portion that is a part of the cushion frame can contact during a rear collision of the vehicle. The contact portion is a cross bar extending in the width direction of the seat, and a pair of protrusions are provided so as to be separated from each other in the width direction, and the pair of protrusions are arranged within a range inside the cushion frame in the width direction. It is characterized by this.

[0008] According to such a configuration, in a configuration having a link mechanism capable of adjusting the height of a seat cushion, a mounting bracket attached to the floor portion of the passenger compartment among the link mechanisms has a protruding portion integrally formed thereon that extends upward. This protruding portion abuts against a portion to be abutted, which is a part of the cushion frame, at the abutting surface on the upper surface side of the protruding portion when the seat reclines during a vehicle collision, and thereby it is possible to suppress the tilting angle of the link arm. As a result, the portion to be abutted fixed to the cushion frame directly abuts against a mounting bracket having sufficient strength to receive a load, so there is no need to newly provide a member that receives a load separately from the link mechanism (that is, a separate member such as a conventional stop element). As a result, it is possible to suppress the increase in the weight of the seat while suppressing the recline of the seat during a rear collision. Further, in the vehicle seat, the contact portion is a cross bar extending in the width direction of the seat, and a pair of protrusions are provided so as to be separated from each other in the width direction, and the pair of protrusions are arranged within a range inside the cushion frame in the width direction. According to this configuration, since the pair of protrusions are arranged inside the cushion frame in the width direction, even when the seat is deformed in the width direction, the protrusions can surely contact the cross bar, and it is possible to suppress the deformation of the seat in the width direction.

[0009] In the vehicle seat, it is preferable that the portion to be abutted rotatably supports the link arm, and the height of the abutting surface is set to a height at which the abutting surface approaches the portion to be abutted in a state where the cushion frame is in the second position.

[0010] According to such a configuration, the protruding portion of the mounting bracket abuts against the portion to be abutted at a position closer to the seat surface side (that is, the upper surface side of the seat cushion) during a rear collision of the vehicle and receives the load from the portion to be abutted, so it is easy to suppress variations in the tilting angle of the link arm due to deformation of the seat. In addition, even for a seat having a high height to the seat surface, it is possible to extend the protruding portion upward to cope with it, and it is possible to suppress variations in the tilting angle of the link arm even in such a seat.

[0011] In the vehicle seat, it is preferable that the height of the abutting surface is set to a height at which a gap can be formed between the abutting surface and the portion to be abutted in a state where the cushion frame is in the second position.

[0012] According to such a configuration, during normal vehicle use, that is, when the vehicle is not rear-ended, in a state where the cushion frame is in the second position, it is possible to reliably avoid contact between the contact surface of the protrusion and the contact portion of the cushion frame. Thereby, it is possible to prevent the generation of abnormal noise due to contact between the contact surface and the contact portion during vehicle travel.

[0013] In the vehicle seat described above, the link mechanism is fixed to the connecting portion of the link arm and the contact portion, and further includes a reinforcing plate that reinforces the link arm. The contact surface of the protrusion preferably has a length in the vehicle longitudinal direction that allows the contact portion and the reinforcing plate to contact simultaneously.

[0014] According to such a configuration, by widely securing the contact surface of the protrusion in the vehicle longitudinal direction, the contact surface can receive not only the load from the contact portion but also the load from the reinforcing plate, and it is possible to prevent the load during a rear-end collision from concentrating at one point on the contact surface.

[0017] In the vehicle seat described above, at least a part of the rear side portion of the contact surface including the rear end of the contact surface in the vehicle longitudinal direction is preferably set higher than the front side portion including the front end of the contact surface.

[0018] According to such a configuration, even when the tilting angles and front-rear positions of the link arms vary on both the left and right sides in the seat width direction, the contact portion is positioned at a predetermined position when it contacts the protrusion. In addition, the contact surface can receive the contact portion at a plurality of locations, and the load during a rear-end collision can be dispersed over a wide range of the contact surface.

[0019] In the vehicle seat described above, the rear side portion of the contact surface is preferably inclined so as to rise gently in an arc shape toward the rear side of the vehicle.

[0020] According to such a configuration, it is possible to increase the contact area between the contacted portion and the contact surface, and as a result, it is possible to prevent damage to the contact surfaces of the protrusions and the cross bars.

Advantages of the Invention

[0021] According to the seat of the present invention, it is possible to suppress the backward tilt of the seat during a rear collision while suppressing an increase in the weight of the seat.

Brief Description of the Drawings

[0022]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Mode for Carrying Out the Invention

[0023] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0024] As shown in FIGS. 1 to 2, the vehicle seat 1 (hereinafter referred to as the seat 1) of the present embodiment is a seat attached to the passenger compartment of a vehicle, and includes a seat cushion 2 against which the buttocks of a seated person can abut, and a link mechanism 6 capable of adjusting the height of the seat cushion 2.

[0025] Specifically, the seat 1 includes the above-described seat cushion 2, a seat back 3 against which the back of a seated person can abut, a seat frame 4, a guide rail 5, and a link mechanism 6.

[0026] The seat frame 4 includes a cushion frame 7 that supports the seat cushion 2 from below, and a back frame 8 that supports the seat back 3 from behind in an upright state. The cushion frame 7 has a pair of side portions 7a that are spaced apart from each other on both sides in the width direction Y of the seat 1 and extend in the vehicle front-rear direction X. Note that the cushion frame 7 is shared by the seat frame 4 and the link mechanism 6.

[0027] The guide rail 5 includes a pair of lower rails 9 that extend in the vehicle longitudinal direction X and are fixed to the floor surface of the passenger compartment at positions spaced apart from each other, and a pair of upper rails 10 that are slidably guided in the vehicle longitudinal direction X by the pair of lower rails 9.

[0028] As shown in FIGS. 2 to 5, the link mechanism 6 includes the cushion frame 7, a pair of mounting brackets 11 located below the pair of side portions 7a of the cushion frame 7 on the lower Z2 side, and a plurality of link arms (that is, a pair of front link arms 12 and a pair of rear link arms 13). Further, in the present embodiment, the link mechanism 6 further includes a front cross bar 14 and a rear cross bar 15 as part of the cushion frame 7. Each of the pair of rear link arms 13 includes a reinforcing plate 16 for reinforcement straddling the rear cross bar 15, and the pair of mounting brackets 11 includes a pair of protrusions 17 that can abut against the rear cross bar 15 when a load F is applied to the mounting brackets 11 from the rear X2 side (as shown in FIG. 2) during a rear collision of the vehicle.

[0029] The pair of mounting brackets 11 are directly or indirectly attached to the floor portion of the passenger compartment. In the present embodiment, the pair of mounting brackets 11 are fixed to the pair of upper rails 10 of the guide rail 5 by bolts or the like (for example, the stud bolts 26 and nuts 27 on the upper surface of the upper rail 10 in FIG. 7). In other words, they are indirectly attached to the floor portion of the passenger compartment via the guide rail 5. The mounting brackets 11 are made of a highly rigid material such as steel. In the present embodiment, as shown in FIGS. 7 to 8, the pair of mounting brackets 11 are connected by a lower cross bar 25, thereby improving the rigidity of the mounting brackets 11.

[0030] A plurality of link arms, namely, a pair of front link arms 12 and a pair of rear link arms 13, link the cushion frame 7 and the mounting bracket 11 so that the cushion frame 7 can move between a first position (a position above the cushion frame 7 in FIG. 2, on the Z1 side) and a second position (the position shown in FIGS. 2 to 7, on the X2 side and the Z2 side rearward of the vehicle with respect to the first position) while maintaining parallelism with respect to the mounting bracket 11. Specifically, the lower ends of the pair of front link arms 12 are rotatably supported at the respective front support portions 11a of the pair of mounting brackets 11 about a rotation axis C1, and the upper ends thereof are rotatably connected to the pair of side portions 7a of the cushion frame 7 via a front cross bar 14. Similarly, the lower ends of the pair of rear link arms 13 are rotatably supported at the respective rear support portions 11b of the pair of mounting brackets 11 about a rotation axis C2, and the upper ends thereof are rotatably connected to the pair of side portions 7a of the cushion frame 7 via a rear cross bar 15.

[0031] That is, in the present embodiment, the front cross bar 14 rotatably supports the pair of front link arms 12 located on both sides in the width direction Y of the seat 1. Similarly, the rear cross bar 15 rotatably supports the pair of rear link arms 13 located on both sides in the width direction Y of the seat 1.

[0032] The front cross bar 14 and the rear cross bar 15, which are part of the cushion frame 7, extend in the width direction Y of the seat 1 and are arranged so as to be spaced apart from each other in the vehicle front-rear direction X. Both ends of each of the front cross bar 14 and the rear cross bar 15 are fixed to the pair of side portions 7a of the cushion frame 7, respectively.

[0033] In the present embodiment, the rear cross bar 15 functions as an abutting portion that can abut against the pair of protrusions 17.

[0034] The reinforcing plate 16 is fixed to the connecting portion of the rear link arm 13 and the rear cross bar 15 by welding or the like to reinforce the rear link arm 13.

[0035] As shown in FIGS. 2 to 6 (particularly FIGS. 5 to 6), the protrusion 17 is integrally formed with the mounting bracket 11 and protrudes upward from the upper surface of the mounting bracket 11 toward the Z1 side. The protrusion 17 has a contact surface 18 on its upper surface side against which the rear cross bar 15 can contact during a rear collision of the vehicle.

[0036] In the present embodiment, as shown in FIGS. 2, 7 to 8, and 10, a pair of protrusions 17 are provided so as to be spaced apart from each other in the width direction Y of the seat 1. The pair of protrusions 17 are arranged within a range inside the cushion frame 7 in the width direction Y.

[0037] The height H0 of the contact surface 18 and the length L1 in the vehicle longitudinal direction X shown in FIG. 6 are set to dimensions such that the contact surface 18 of the protrusion 17 always contacts the rear cross bar 15 even if the position at which the rear cross bar 15 descends during a rear collision of the vehicle varies.

[0038] For example, as shown in FIG. 6, the height H0 of the contact surface 18 (specifically, the height from the lower surface 11c of the mounting bracket 11 to the contact surface 18) is set to a height at which the contact surface 18 approaches the rear cross bar 15, which is the contacted portion, in a state where the cushion frame 7 is in the second position. Specifically, the height H0 of the contact surface 18 is set to a height at which a gap can be formed between the contact surface 18 and the rear cross bar 15 in a state where the cushion frame 7 is in the second position. By setting the height H0 of the contact surface 18 in this way, during a rear collision of the vehicle, the contact surface 18 can contact the rear cross bar 15 to suppress the tilting angle of the rear link arm 13. The height H0 of the contact surface 18 is appropriately set according to various conditions such as the distance between the cushion frame 7 in the second position and the mounting bracket 11, the length of the rear link arm 13, and the position of the rear cross bar 15.

[0039] In this embodiment, the contact surface 18 of the protrusion 17 has a length L1 in the vehicle longitudinal direction X that allows the rear crossbar 15 and the reinforcing plate 16 to contact simultaneously. For example, when the outer diameter D of the rear crossbar 15 is about 25 mm, the length L1 of the contact surface 18 is set to 30 - 35 mm (about 33 mm). Also, the front portion 18a including the front end of the contact surface 18 is formed as a flat surface. The total length L2 of the front portion 18a and the gently sloping intermediate portion 18c is set to about 15 - 25 mm (about 20 mm).

[0040] The protrusion 17 is preferably set to a dimension that can ensure a cross-section capable of withstanding a large load received from the rear crossbar 15. That is, the protrusion 17 preferably has a rigidity such that it does not deform when the rear crossbar 15 contacts it during a rear collision of the vehicle.

[0041] At least a part of the rear portion 18b of the contact surface 18 including the rear end of the contact surface 18 in the vehicle longitudinal direction X is set higher than the front portion 18a including the front end of the contact surface 18. Specifically, the rear portion 18b of the contact surface 18 is inclined so as to become higher as it goes toward the rear X2 side of the vehicle so as to be continuous with the front portion 18a. For example, the height H1 of the rear end of the rear portion 18b of the contact surface 18 (that is, the height of the rear end of the rear portion 18b with respect to the surface of the front portion 18a) is set to, for example, 2 - 10 mm (about 5 mm) as a height that can suppress the displacement of the rear crossbar 15 toward the rear X2 side and position it at a predetermined position. Thereby, when the rear crossbar 15 contacts the contact surface 18 of the protrusion 17 during a rear collision of the vehicle, the rear crossbar 15 is prevented from shifting toward the rear X2 side.

[0042] More specifically, the rear portion 18b of the contact surface 18 is inclined so as to rise gradually in an arc shape as it goes toward the rear X2 side of the vehicle. The arc shape of the rear portion 18b is set to a shape or a radius of curvature such that the rear portion 18b contacts (or has a wide-area surface contact) with the cylindrical rear crossbar 15 at a plurality of locations. For example, when the radius of curvature R2 of the outer peripheral surface of the rear crossbar 15 is 12 to 13.5 mm (about 12.7 mm), the radius of curvature R1 of the rear portion 18b is set to 14 to 16.5 mm (about 15.7 mm). Thereby, when the rear crossbar 15 contacts the contact surface 18 of the protrusion 17 during a rear collision of the vehicle, the contact area between the outer peripheral surface of the rear crossbar 15 and the rear portion 18b of the contact surface 18 becomes wide, and it is possible to disperse the load on the contact surface 18.

[0043] In the seat 1 configured as described above, in a state before a rear collision of the vehicle (a state where the cushion frame 7 is in the second position), as shown in FIGS. 2, 7, and 10(a), a gap is secured between the rear crossbar 15 and the protrusion 17.

[0044] On the other hand, during a rear collision of the vehicle, as the seated person of the seat 1 relatively moves rearward in the passenger compartment due to inertia, the cushion frame 7 and the rear crossbar 15, which is the portion to be abutted thereon, move further downward to the Z2 side from the second position shown in FIGS. 2 to 5 and 7 by that inertial force. At this time, as shown in FIGS. 8 to 9 and 10(b), when the rear crossbar 15 contacts the contact surface 18 of the protrusion 17, the tilting angle of the rear link arm 13 can be suppressed, and as a result, it is possible to prevent the seat 1 from tilting backward.

[0045] (Features of this Embodiment) (1) As shown in FIGS. 1 to 2, the vehicle seat according to the present embodiment includes a seat cushion 2 against which the buttocks of a seated person can abut, and a link mechanism 6 capable of adjusting the height of the seat cushion 2. As shown in FIGS. 2 to 6, the link mechanism 6 includes a cushion frame 7 that supports the seat cushion 2, a mounting bracket 11 that is directly or indirectly attached to the floor portion of the vehicle compartment, and a first position while the cushion frame 7 maintains parallelism with the mounting bracket 11, and a second position on the X2 side (rearward of the vehicle) and Z2 side (downward) with respect to the first position. A pair of front link arms 12 and a pair of rear link arms 13 as a plurality of link arms that link the cushion frame 7 and the mounting bracket 11 so as to be movable therebetween, a rear cross bar 15 as a contact portion that is a part of the cushion frame 7, and a protrusion 17.

[0046] The protrusion 17 is integrally formed with the mounting bracket 11 and protrudes upward on the Z1 side from the upper surface of the mounting bracket 11, and has a contact surface 18 on the upper surface side against which the rear cross bar 15 can abut during a rear collision of the vehicle.

[0047] According to such a configuration, in a configuration including the link mechanism 6 capable of adjusting the height of the seat cushion 2, a protrusion 17 extending upward on the Z1 is integrally formed on the mounting bracket 11 attached to the floor portion of the vehicle compartment among the link mechanisms 6.

[0048] As shown in FIGS. 7 to 9, when the seat tilts backward during a vehicle collision, the protrusion 17 abuts against the rear cross bar 15 as a contact portion that is a part of the cushion frame 7 at the contact surface 18 on the upper surface side of the protrusion 17, whereby it is possible to suppress the tilting angle of the rear link arm 13. As a result, the rear cross bar 15 fixed to the cushion frame 7 directly abuts against the mounting bracket 11 having sufficient strength to receive the load, so there is no need to newly provide a member that receives the load separately from the link mechanism 6 (that is, a separate member such as a conventional stop element). As a result, it is possible to suppress the increase in the weight of the seat while suppressing the backward tilt of the seat during a rear collision.

[0049] In other words, in the structure in which the existing mounting bracket 11 of the link mechanism 6 is provided with the protrusion 17 that receives the load during a rear collision as in the seat 1 of the present embodiment, since it is received at a location that already has sufficient strength, there is no need to newly provide or reinforce the structure, so it is possible to suppress the occurrence of costs related to the new structure and reinforcement.

[0050] Further, even when the mounting bracket in the existing link mechanism does not have the protrusion 17 as described above, by replacing it with the mounting bracket 11 having the protrusion 17 or replacing it with another mounting bracket 11 with the height of the protrusion 17 changed, it is easy to add a function of controlling the tilting angle of the rear link arm 13 retroactively.

[0051] (2) In the vehicle seat of the present embodiment, as shown in FIGS. 2, 7 to 8, and 10, the rear crossbar 15 rotatably supports a pair of rear link arms 13. The height H0 (see FIG. 6) of the contact surface 18 is set to a height at which the contact surface 18 approaches the rear crossbar 15 in a state where the cushion frame 7 is in the second position.

[0052] According to such a configuration, the protrusion 17 of the mounting bracket 11 contacts the rear crossbar 15 at a position closer to the seat surface side (that is, the upper surface side of the seat cushion 2) during a rear collision of the vehicle and receives the load from the rear crossbar 15, so it is easy to suppress variations in the tilting angle of the rear link arm 13 due to deformation of the seat. Further, even for a seat with a high height up to the seat surface, it is possible to extend the protrusion 17 upward on the Z1 side to cope with it, and it is possible to suppress variations in the tilting angle of the rear link arm 13 even in such a seat.

[0053] In other words, the protrusion 17 is provided at a position where it can contact the rear cross bar 15, which serves as the rotation axis on the cushion frame 7 side of the rear link arm 13 during a rear-end collision of the vehicle. As a result, the protrusion 17 can receive the load closer to the seat surface and closer to the load input point. Therefore, the deformation of the seat 1 above the position where the protrusion 17 contacts the rear cross bar 15 is small, and it is possible to suppress variations in the tilting angle of the rear link arm 13. Further, in the present embodiment, since the protrusion 17 extends upward in the Z1 direction from the mounting bracket 11 attached to the upper rail 10 of the guide rail 5, it is possible to easily cope with a seat structure having a high height from the guide rail 5 to the cushion frame 7 by extending the protrusion 17.

[0054] Here, when a regulating portion (a portion corresponding to the protrusion 17 of the present embodiment) for regulating the link tilting angle during rearward tilting is provided on the link side as in a conventional seat (for example, the seat disclosed in Japanese Patent No. 5866159), interference with other components occurs when the regulating portion is extended upward to cope with an increase in the distance between the guide rail 5 and the cushion frame 7. Further, if an attempt is made to cope with the situation with the link side unchanged, it is necessary to newly provide a structure for contacting the regulating portion. On the other hand, in the seat of the present embodiment, by providing the protrusion 17 on the mounting bracket 11 of the link mechanism 6, it is possible to easily cope with an increase in the distance between the guide rail 5 and the cushion frame 7 by changing the height of the protrusion 17 accordingly.

[0055] (3) In the vehicle seat of the present embodiment, it is preferable that the height H0 of the contact surface 18 is set to a height at which a gap can be formed between the contact surface 18 and the rear cross bar 15 in a state where the cushion frame 7 is in the second position.

[0056] According to such a configuration, during normal vehicle use, that is, when the vehicle is not rear-ended, in a state where the cushion frame 7 is in the second position, it is possible to reliably avoid contact between the contact surface 18 of the protrusion 17 and the rear cross bar 15 which is the portion to be contacted of the cushion frame 7. Thereby, it is possible to prevent the generation of abnormal noise due to contact between the contact surface 18 and the rear cross bar 15 during vehicle travel.

[0057] (4) In the vehicle seat of the present embodiment, as shown in FIGS. 2 to 5, the link mechanism 6 is fixed to the connecting portion of the rear link arm 13 and the rear cross bar 15, and further includes a reinforcing plate 16 for reinforcing the rear link arm 13.

[0058] The contact surface 18 of the protrusion 17 has a length L1 (see FIG. 6) in the vehicle longitudinal direction X that allows the rear cross bar 15 and the reinforcing plate 16 to contact simultaneously.

[0059] According to such a configuration, by widely securing the contact surface 18 of the protrusion 17 in the vehicle longitudinal direction X, the contact surface 18 can receive not only the load from the rear cross bar 15 but also the load from the reinforcing plate 16, preventing the load during a rear-end collision from concentrating on one point on the contact surface 18.

[0060] (5) In the vehicle seat of the present embodiment, the portion to be contacted of the cushion frame 7 is a rear cross bar 15 extending in the seat width direction Y.

[0061] As shown in FIGS. 2, 7 to 8, and 10, a pair of protrusions 17 are provided on both sides in the width direction Y of the seat 1 so as to be spaced apart from each other in the width direction Y. The pair of protrusions 17 are arranged within a range inside the cushion frame 7 in the width direction Y.

[0062] According to such a configuration, since the pair of protrusions 17 are arranged inside the cushion frame 7 in the width direction Y, even when the seat is deformed in the width direction Y, the protrusions 17 can surely contact the rear cross bar 15, and it is possible to suppress the deformation of the seat in the width direction Y.

[0063] Also, in this configuration, even if the seat is deformed in the width direction Y (see Fig. 10(b)), the pair of protrusions 17 can surely receive the rear cross bar 15, and the deformation of the seat 1 in the width direction Y can also be suppressed by the contact between the side surface of the protrusion 17 and structures such as the cushion frame 7.

[0064] Here, in the case of a conventional seat structure, for example, a conventional seat structure that regulates the rearward tilt of the seat and also regulates the displacement in the seat width direction (for example, a structure having a contact portion on the link side and a regulating portion on the bracket side described in Japanese Patent No. 6838492), when the seat is largely displaced in the seat width direction, the contact portion may not be able to contact the regulating portion at a predetermined position, and there is a possibility that the rearward tilt of the seat and the regulation of the displacement in the seat width direction cannot be achieved. On the other hand, in the seat of the present embodiment, by providing the protrusion 17 that regulates the rearward tilt inside the width direction Y of the cushion frame 7, no matter which way the seat is deformed in the width direction Y, it is possible to surely contact the rear cross bar 15 and the pair of protrusions 17 to regulate the rearward tilt of the seat. Moreover, by having the cushion frame 7, the rear link arm 13, etc. contact the protrusion 17 in addition to the rear cross bar 15, it is possible to surely suppress the position of the cushion frame 7 and the displacement in the width direction Y.

[0065] (6) In the vehicle seat of the present embodiment, as shown in Figs. 5 to 6 and Fig. 9, at least a part of the rear side portion 18b of the contact surface 18 including the rear end of the contact surface 18 in the vehicle front-rear direction X is set higher than the front side portion 18a including the front end of the contact surface 18. Specifically, the rear side portion 18b of the contact surface 18 is inclined so as to become higher as it goes toward the vehicle rear X2 side.

[0066] According to such a configuration, even when the tilting angles and the front-rear positions of the rear link arms 13 vary on both the left and right sides in the sheet width direction Y, the rear crossbar 15 is positioned at a predetermined position when it comes into contact with the protrusion 17. Further, the contact surface 18 can receive the rear crossbar 15 at a plurality of locations, and the load during a rear collision can be dispersed over a wide range of the contact surface 18.

[0067] Also, by setting the rear portion 18b of the contact surface 18 of the protrusion 17 to be relatively higher than the front portion 18a, it is possible to absorb variations in the displacement of the rear crossbar 15 in the vehicle front-rear direction X and position the rear crossbar 15 at a predetermined position.

[0068] Here, in the case of a structure in which the inner peripheral surface of an arcuate recess formed in a link arm and the outer peripheral surface of a columnar crossbar fixed to a cushion frame are in contact, as in a conventional seat (Japanese Patent No. 5866159), the contact surfaces of the link arm and the crossbar extend in an arc shape and are parallel to each other. For this reason, it is necessary to widen the range of the arcuate recess on the receiving side in order to absorb variations in the relative positions of the contact surfaces. On the other hand, in the seat of the present embodiment, by making the rear portion of the contact surface 18 of the protrusion 17 relatively higher, it is possible to absorb variations in the displacement of the rear crossbar 15 and position the rear crossbar 15 at a predetermined position.

[0069] (7) In the vehicle seat of the present embodiment, as shown in FIGS. 5 to 6, the rear portion 18b of the contact surface 18 is inclined so as to gradually rise in an arc shape as it goes toward the vehicle rear X2 side.

[0070] According to such a configuration, it is possible to increase the contact area between the rear crossbar 15 and the contact surface 18, and as a result, it is possible to prevent damage to the contact surfaces of the protrusion 17 and the rear crossbar 15 (that is, the contact surface 18 of the protrusion 17 and the outer peripheral surface of the rear crossbar 15).

[0071] More specifically, the rear portion 18b of the contact surface 18 is inclined so as to rise gently in an arc shape from near the middle of the contact surface 18, thereby increasing the contact area with the rear crossbar 15 and preventing the load from concentrating on a single point on the contact surface 18.

[0072] (8) In the vehicle seat of the present embodiment, the mounting bracket 11 of the link mechanism 6 has a rear support portion 11b that rotatably supports the lower portion of the rear link arm 13. Therefore, both the rear support portion 11b and the protrusion 17 are integrally formed so as to be part of the mounting bracket 11.

[0073] As a result, during a rear collision, the upper and lower portions of the rear link arm 13 are simultaneously constrained by a single mounting bracket 11. That is, the lower portion of the rear link arm 13 is constrained by the rear support portion 11b of the mounting bracket 11, and the upper portion of the rear link arm 13 is constrained by the protrusion 17 via the rear crossbar 15. Thereby, it is possible to reliably prevent the rear link arm 13 and the cushion frame 7 connected thereto from moving toward the rear X2 side of the vehicle.

[0074] (Modification) (A) In the above embodiment, the rear crossbar 15 is cited as an example of the contact portion that contacts the protrusion 17 integrally formed on the mounting bracket 11 of the link mechanism 6, but the present invention is not limited thereto. The contact portion of the present invention may be any part that constitutes the cushion frame 7, for example, a part other than the rear crossbar 15 in the cushion frame 7.

[0075] (B) In the above embodiment, the protrusion 17 has rigidity such that it does not deform when the rear crossbar 15 contacts it during a rear collision of the vehicle. However, when receiving a stronger impact from a rear collision, the protrusion 17 may buckle to absorb the impact and mitigate the impact on the seated person.

[0076] For example, in order to support the rear crossbar 15 located at the rear X2 of the rear link arm 13, the height of the protrusion 17 is increased. By utilizing this, when a stronger rear collision is received, it may be possible to absorb the impact by buckling.

[0077] Also, in order to ensure that the protrusion 17 deforms and absorbs the impact at a load exceeding the assumed load, the broken line 20 shown in FIG. 11 or the groove 21 shown in FIG. 12 may be formed in the protrusion 17. Due to these broken lines 20 and grooves 21, it becomes possible to absorb the impact by intentionally buckling the protrusion 17 rather than buckling randomly.

[0078] Also, when the height of the protrusion 17 cannot withstand the load at the time of receiving an assumed rear collision, reinforcing parts such as ribs 22 and beads may be added.

Explanation of Reference Numerals

[0079] 1 Seat 2 Seat Cushion 4 Seat Frame 5 Guide Rail 6 Link Mechanism 7 Cushion Frame 9 Lower Rail 10 Upper Rail 11 Mounting Bracket 12 Front Link Arm 13 Rear Link Arm 14 Front Crossbar 15 Rear Crossbar (Contacted Portion) 16 Reinforcing Plate 17 Protrusion 18 Contact Surface 18a Front Portion 18b Rear Portion

Claims

1. A vehicle seat comprising a seat cushion and a link mechanism capable of adjusting the height of the seat cushion, wherein the link mechanism includes a cushion frame that supports the seat cushion, a mounting bracket directly or indirectly attached to the floor of the vehicle cabin, a plurality of link arms that link and couple the cushion frame and the mounting bracket so that the cushion frame can move between a first position while maintaining parallelism with the mounting bracket and a second position that is rearward and downward of the vehicle relative to the first position, a protrusion integrally formed on the mounting bracket and protruding upward from the upper surface of the mounting bracket, the protrusion having a contact surface on the upper surface side against which a contact portion, which is a part of the cushion frame, can contact during a rear collision of the vehicle, and is provided with the contact portion is a crossbar extending in the width direction of the seat, a pair of the protrusions are provided so as to be spaced apart from each other in the width direction, the pair of protrusions are arranged within a range inside the cushion frame in the width direction, characterized in that it is a vehicle seat.

2. In the vehicle seat according to Claim 1, the contact portion rotatably supports the link arm, the height of the contact surface is set to a height at which the contact surface approaches the contact portion in a state where the cushion frame is in the second position, characterized in that it is a vehicle seat.

3. In the vehicle seat according to Claim 2, the height of the contact surface is set to a height at which a gap can be formed between the contact surface and the contact portion in a state where the cushion frame is in the second position, characterized in that it is a vehicle seat.

4. In the vehicle seat according to Claim 2 or 3, the link mechanism further includes a reinforcing plate fixed to a connecting portion of the link arm and the contact portion to reinforce the link arm, the contact surface of the protrusion has a length in the vehicle longitudinal direction that allows the contact portion and the reinforcing plate to contact simultaneously, characterized in that it is a vehicle seat.

5. In the vehicle seat according to any one of Claims 1 to 4, at least a part of the rear side portion of the contact surface including the rear end of the contact surface in the vehicle longitudinal direction is set higher than the front side portion including the front end of the contact surface, characterized in that it is a vehicle seat.

6. In the vehicle seat according to claim 5, a rear portion of the contact surface is inclined so as to rise so as to gently draw an arc as it goes toward the rear side of the vehicle. A vehicle seat characterized by this.

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