Seat rail

Abstract

To provide a seat rail which can inhibit an upper rail from falling from a lower rail in a state that the upper rail and the lower rail are arranged offset from each other.SOLUTION: A seat rail supports a vehicle seat so that the seat may move in a front-back direction and includes: a lower rail which extends in the front-back direction, is fixed to a portion to which the seat is attached, and forms a hat shaped cross section which is open to the upper side; an upper rail which extends in the front-back direction, is fixed to the seat, has a C shaped cross section which is open to the lower side, and engages with the lower rail slidably in the front-back direction; and a reinforcement member forming a C shaped cross section which covers the upper rail and is open to the lower side and fitted in the outer side of the upper rail so as to reinforce at least an opening peripheral edge of the upper rail. The reinforcement member is provided in a predetermined range in the front-back direction including a rear end position of the lower rail when the seat is moved to a rearmost position.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] A seat provided in a vehicle is movable back and forth by being provided via a rail device.

[0003] For example, the rail device of the vehicle seat of Patent Document 1 below is a device that supports a seat body so as to be slidable in the seat front-rear direction, and is disposed between the seat body and the vehicle body floor. This rail device includes a lower rail and an upper rail. The lower rail is fixed to the vehicle body floor, the upper rail is fixed to the seat body, and is slidably supported along the lower rail.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In such a rail device, an upward force may act on the rear end of the upper rail. For example, when preventing a seated person from being thrown forward by a seat belt provided on the seat, the seat belt is pulled by the seated person. Thus, when the seat belt is pulled by the seated person, an upward force acts on the rear end of the upper rail via the seat.

[0006] When the seat position is on the rear end side, there is a rail device configured such that the upper rail extends rearward beyond the rear end of the lower rail. When such an upper rail is displaced (offset) rearward with respect to the lower rail, if an upward force acts on the rear end of the upper rail as described above, an excessive moment force acts on the rear end position of the lower rail. When such an excessive moment force acts, the upper rail may deform so as to open outward, and there is a risk that the upper rail may fall off from the rear end of the lower rail.

[0007] Furthermore, when the upper rail deforms, there is also a risk that the seat may tilt forward.

[0008] The present invention has been made in view of the above problems, and an object thereof is to provide a seat rail capable of suppressing the upper rail from falling off the lower rail even when the upper rail and the lower rail are in an offset state.

Means for Solving the Problems

[0009] The present invention has been made to solve at least a part of the above problems, and can be realized as the following aspects or application examples.

[0010] The seat rail according to this application example is a seat rail that supports a vehicle seat so as to be movable in the front-rear direction, and includes a lower rail that extends in the front-rear direction, is fixed to the attachment destination of the seat, and has a cross-sectional hat shape that opens upward, and an upper rail that extends in the front-rear direction, is fixed to the seat, has a cross-sectional C shape that opens downward, and is slidably engaged with the lower rail in the front-rear direction, and a reinforcing member that has a cross-sectional C shape that opens downward and covers the upper rail and is fitted outside the upper rail so as to reinforce at least the opening peripheral edge of the upper rail. The reinforcing member is provided in a predetermined range in the front-rear direction including the rear end position of the lower rail when the seat is moved to the rearmost position.

[0011] According to this applicable example, when the seat is moved to the rearmost position, on the upper rail, the reinforcing member is located within a predetermined range in the front-rear direction including the rear end position of the lower rail. Thereby, even when the upper rail is displaced rearward with respect to the lower rail and an upward moment force acts on the rear end position of the lower rail, the dropout of the upper rail is suppressed by the resistance force based on the rigidity of both the upper rail and the reinforcing member. Thereby, even in a state where the upper rail and the lower rail are offset, it is possible to suppress the upper rail from dropping out of the lower rail.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Modes for Carrying Out the Invention

[0013] FIG. 1 is a schematic perspective view showing an example of the configuration of the seat 10 and the seat rail 50 of this embodiment. FIG. 2 is a schematic perspective view enlarging the periphery of the seat rail 50 shown in FIG. 1. First, the configuration of the seat 10 will be described with reference to FIGS. 1 and 2.

[0014] In the following description, the front-rear direction (X direction) means the front-rear direction as viewed from the seat occupant of the seat 10. Also, the left-right direction (Y direction) means the left-right direction as viewed from the seat occupant of the seat 10. Further, the up-down direction (Z direction) means the up-down direction of the seat 10.

[0015] Also, in the present embodiment, as an example of the vehicle, a vehicle will be described. Therefore, the front-rear direction corresponds to the front-rear direction of the vehicle (not shown) on which the seat 10 is mounted, the left-right direction corresponds to the left-right direction of the vehicle, and the up-down direction corresponds to the up-down direction of the vehicle.

[0016] Furthermore, in the following description, for a pair of symmetric parts, the symbol of the right-side part may be suffixed with R and the symbol of the left-side part may be suffixed with L for distinction.

[0017] The seat 10 is a vehicle seat. Specifically, the seat 10 is a vehicle seat. The seat 10 has a substantially L-shaped configuration and includes a seating portion 12, a backrest portion 14, and a leg portion 16, etc.

[0018] The seating portion 12 has a plate shape and supports the buttocks of the seat occupant. Specifically, the seating portion 12 includes a cushion (not shown) and a frame (not shown) that supports the cushion, etc.

[0019] The backrest portion 14 has a plate shape that extends so as to intersect the seating portion 12 and supports the back of the seat occupant. Specifically, the backrest portion 14 includes a cushion (not shown) and a frame (not shown) that supports the cushion, etc.

[0020] Also, the frame of the seating portion 12 and the frame of the backrest portion 14 are connected to each other via a reclining mechanism (not shown), and the backrest portion 14 is tiltable about a rotation axis extending in the left-right direction at the rear of the seating portion 12 as a fulcrum.

[0021] The foot part 16 includes a pair of right and left foot parts, namely a right foot part 16R and a left foot part 16L, which extend in the front-rear direction. The right foot part 16R is provided diagonally below the right side of the seating part 12 and supports the right side of the seating part 12. The left foot part 16L is provided diagonally below the left side of the seating part 12 and supports the left side of the seating part 12.

[0022] Each of the right foot part 16R and the left foot part 16L includes a support part 22, a connecting part 24, etc. The support part 22 is a rod-shaped member that extends in the front-rear direction. The connecting part 24 is a rod-shaped member that extends in the vertical direction and connects the support part 22 and the seating part 12.

[0023] Specifically, each of the right foot part 16R and the left foot part 16L has two connecting parts 24. One connecting part 24 connects the front end of the support part 22 and the seating part 12, and the other connecting part 24 connects the rear end of the support part 22R and the seating part 12.

[0024] The seat 10 can be connected to the seat belt 40 via a connector 30. The connector 30 includes a support part 32, a buckle 34, etc. One end of the support part 32 is fixed to the seat 10, and the other end is connected to the buckle 34. That is, the support part 32 supports the buckle 34.

[0025] The seat belt 40 of this embodiment is a three-point seat belt. When the tongue plate 42 provided on the seat belt 40 is inserted into the buckle 34, the tongue plate 42 and the buckle 34 are locked to each other. Therefore, when the tongue plate 42 is inserted into the buckle 34, the seat belt 40 is connected to the seat 10 via the connector 30.

[0026] One end of the support part 32 is fixed to the connection point P on the right side of the seat 10. That is, the seat belt 40 is specifically connected to the connection point P on the right side of the seat 10 via the connector 30. Further, the connection point P of the seat 10 with the seat belt 40 is located behind the seat 10 and below the seat surface 12a of the seating part 12. Also, the seat belt 40 has two other connection points (not shown) on the vehicle body (not shown) side.

[0027] From these facts, in the state where the seat belt 40 is connected to the seat 10, the seat belt 40 extends so as to straddle the left and right sides of the seat 10 and covers the chest and waist of the seated person.

[0028] Next, in addition to FIGS. 1 and 2, the specific configuration of the seat rail 50 will be described with reference to FIG. 3. FIG. 3 is a schematic cross-sectional view showing a cross-section A of the seat rail 50 shown in FIG. 2.

[0029] The seat rail 50 supports the seat 10 so as to be movable in the front-rear direction. The seat rail 50 includes a pair of right seat rails 50R and a left seat rail 50L, which extend in the front-rear direction.

[0030] Each of the right seat rail 50R and the left seat rail 50L includes a lower rail 60, an upper rail 70, and the like. Since the right seat rail 50R and the left seat rail 50L have the same configuration, the same reference numerals will be used for each part for explanation.

[0031] The lower rail 60 extends in the front-rear direction and is fixed to the mounting destination of the seat 10 with fixing tools (not shown) such as bolts and nuts. The mounting destination of the seat 10 is the upper surface of the base S (see FIG. 2) provided on the floor surface of the vehicle body. Also, as shown in FIG. 3, the lower rail 60 has a cross-sectional hat shape that opens upward.

[0032] The lower rail 60 includes a lower wall 62, side walls 64, and flanges 66, etc., which extend in the front-rear direction. The lower wall 62 is fixed to the attachment point of the seat 10 by a fixture (not shown).

[0033] The side walls 64 include a pair of right side walls 64R and a left side wall 64L, which stand upright from both side edges of the lower wall 62. Specifically, the right side wall 64R stands upright from the right side edge of the lower wall 62, and the left side wall 64L stands upright from the left side edge of the lower wall 62.

[0034] The flanges 66 include a pair of right flanges 66R and a left flange 66L, which extend away from each other from the upper edges of the side walls 64. Specifically, the right flange 66R extends rightward from the upper edge of the right side wall 64R, and the left flange 66L extends leftward from the upper edge of the left side wall 64L.

[0035] The upper rail 70 extends in the front-rear direction and is fixed to the lower surface of the support portion 22 of the leg portion 16 of the seat 10. As shown in FIG. 3, the upper rail 70 has a C-shaped cross section that opens downward and engages slidably in the front-rear direction with respect to the lower rail 60.

[0036] The upper rail 70 includes an upper wall 72, side walls 74, and flanges 76, etc., which extend in the front-rear direction.

[0037] The upper wall 72 is fixed to the lower surface of the support portion 22 of the leg portion 16 by a fixture (not shown) and is located above the flange 66. Also, both side edges of the upper wall 72 are located outside the flange 66 of the lower rail 60 in the left-right direction.

[0038] The side walls 74 include a pair of right side walls 74R and a left side wall 74L, which hang down from both side edges of the upper wall 72. Specifically, the right side wall 74R hangs down from the right side edge of the upper wall 72, and the left side wall 74L hangs down from the left side edge of the upper wall 72. Also, the lower edges of the side walls 74 are located below the flange 66 of the lower rail 60.

[0039] The flange 76 includes a pair of right flanges 76R on the left and right and a left flange 76L, and these extend from the lower edge of the side wall 74 so as to be close to each other. Specifically, the right flange 76R extends leftward from the lower edge of the right side wall 74R, and the left flange 76L extends rightward from the lower edge of the left side wall 74L.

[0040] From these, the upper rail 70 internally encloses the flange 66, and the side wall 64 of the lower rail 60 is interposed between the flanges 76 of the upper rail 70.

[0041] Also, each of the right seat rail 50R and the left seat rail 50L includes a plurality of rolling elements 80. The rolling elements 80 are spheres that reduce the friction generated as the upper rail 70 slides in the front-rear direction. The plurality of rolling elements 80 are arranged side by side in the front-rear direction between the flange 66 of the lower rail 60 and the flange 76 of the upper rail 70.

[0042] FIG. 4 is a schematic perspective view for explaining the forward movement of the seat 10 of the present embodiment. FIG. 5 is a schematic perspective view for explaining the rearward movement of the seat 10 of the present embodiment. According to such a seat rail 50, as shown in FIG. 4, as the upper rail 70 slides forward with respect to the lower rail 60, the seat 10 moves forward. Also, as shown in FIG. 5, as the upper rail 70 slides rearward with respect to the lower rail 60, the seat 10 moves rearward.

[0043] The seat rail 50 is provided with a restricting mechanism (not shown). The restricting mechanism restricts the sliding range of the upper rail 70 in the front-rear direction. That is, it can be said that the restricting mechanism restricts the moving range of the seat 10 in the front-rear direction. In the example shown in FIG. 4, the upper rail 70 is at the foremost position, that is, the seat 10 is at the foremost position. In the example shown in FIG. 5, the upper rail 70 is at the rearmost position, that is, the seat 10 is at the rearmost position.

[0044] Furthermore, the seat rail 50 is provided with a holding mechanism (not shown). The holding mechanism is a mechanism for holding the position of the upper rail 70 in the front-rear direction. That is, the holding function is also a mechanism for holding the position of the seat 10 in the front-rear direction. The holding mechanism operates in response to the operation of the seated person.

[0045] At least one of the right seat rail 50R and the left seat rail 50L of the present embodiment further includes a reinforcing member 90 (see FIG. 2) for reinforcing the upper rail 70 in addition to the lower rail 60 and the like. In the present embodiment, both the right seat rail 50R and the left seat rail 50L are provided with the reinforcing member 90.

[0046] Next, with reference to FIGS. 1 to 5 in addition to FIG. 6, the specific configuration of the reinforcing member 90 will be described. FIG. 6 is a schematic cross-sectional view showing a B cross-section of the seat rail 50 shown in FIG. 2.

[0047] As shown in FIG. 6, the reinforcing member 90 is fitted outside the upper rail 70 so as to reinforce at least the opening peripheral edge of the upper rail 70. Further, the reinforcing member 90 has a C-shaped cross-section that opens downward and covers the upper rail 70. The reinforcing member 90 is preferably formed of a material having higher rigidity than the seat rail 50.

[0048] The reinforcing member 90 includes an upper wall 92, side walls 94, a flange 96, etc., and these are provided at an intermediate position in the front-rear direction of the upper rail 70. The upper wall 92 is in contact with the upper surface of the upper wall 72 of the upper rail 70. Further, both side edges of the upper wall 92 are located outside both side edges of the upper wall 72 of the upper rail 70 in the left-right direction.

[0049] Note that a recess 22a (see FIG. 2) that is recessed upward is provided at the lower end of the support portion 22 of the leg portion 16. The recess 22a communicates the space on the left side and the space on the right side of the support portion 22. The upper wall 92 of the reinforcing member 90 is inserted in the left-right direction into the gap between the recess 22a and the upper rail 70.

[0050] The side walls 94 include a pair of right and left side walls 94R and 94L. These hang down from both side edges of the upper wall 92, and the respective left - right thicknesses of the right side wall 94R and the left side wall 94L are thicker at the lower side than at the upper side so that the skirt spreads. Also, the lower edge of the side wall 94 is located below the lower edge of the side wall 74 of the upper rail 70.

[0051] Specifically, the right side wall 94R hangs down so as to spread in the left - right direction from the right side edge of the upper wall 92, and its inner surface contacts the right side wall 74R of the upper rail 70. Also, the right side wall 94R increases in thickness toward the right side which is the outer side as it goes downward. The left side wall 94L hangs down so as to spread in the left - right direction from the left side edge of the upper wall 92, and its inner surface contacts the outer side of the upper rail 70. Also, the left side wall 94L increases in thickness toward the left side which is the outer side as it goes downward.

[0052] The flange 96 includes a pair of right and left flanges 96R and 96L, which extend from the lower edge of the side wall 94 so as to approach each other. Specifically, the right flange 96R extends leftward from the lower edge of the right side wall 94R, and its inner surface contacts the lower surface of the right flange 76R of the upper rail 70. Also, the right flange 96R increases in thickness toward the lower side which is the outer side as it goes rightward. The left flange 96L extends rightward from the lower edge of the left side wall 94L, and its inner surface contacts the lower surface of the left flange 76L of the upper rail 70. Also, the left flange 96L increases in thickness toward the lower side which is the outer side as it goes leftward.

[0053] From these, the reinforcing member 90 encloses the upper rail 70. Also, the upper wall 92 of the reinforcing member 90 reinforces the upper wall 72 of the upper rail 70 from the outside, the right side wall 94R of the reinforcing member 90 reinforces the right side wall 74R of the upper rail 70 from the outside, the left side wall 94L of the reinforcing member 90 reinforces the left side wall 74L of the upper rail 70 from the outside, and the flange 96 of the reinforcing member 90 reinforces the flange 76 of the upper rail 70 from the outside. In particular, it can be said that the lower side of the side wall 94 and the flange 96 reinforce the periphery of the opening of the upper rail 70.

[0054] According to the reinforcing member 90, when a force that causes the lower side of the upper rail 70 to warp outward, that is, a force that further opens the opening of the upper rail 70, acts on the upper rail 70, a resistance force based on the rigidity of both the upper rail 70 and the reinforcing member 90 acts to prevent the opening of the upper rail 70 from further opening.

[0055] For example, when an upward force acts on the upper wall 72 of the upper rail 70, a force acts on the upper rail 70 to further open the opening of the upper rail 70, but a resistance force based on the side wall 94, the flange 96, etc. of the reinforcing member 90 acts to prevent the opening of the upper rail 70 from further opening.

[0056] In such a seat rail 50, for example, when the vehicle collides with a building or the like, an upward force may act on the rear end of the upper rail 70. That is, in a state where the seat belt 40 (see FIG. 1) is connected to the seat 10, the expansion and contraction of the seat belt 40 is locked to suppress the occupant from being thrown forward.

[0057] In this case, the seat belt 40 is pulled by the occupant who tries to move forward. The seat belt 40 is connected at the connection point P to the seat 10, and the upper rail 70 is fixed to the leg portion 16 of the seat 10. Therefore, when the seat belt 40 is pulled by the occupant, an upward force acts on the rear end of the upper rail 70 via the connection point P of the seat 10. In particular, a strong load is applied to the upper rail 70 of the right seat rail 50R, which is close to the connection point P between the seat belt 40 and the seat 10.

[0058] Furthermore, as shown in FIG. 5, when the upper rail 70 extends further rearward than the rear end of the lower rail 60, that is, when the upper rail 70 is displaced rearward (offset) with respect to the lower rail 60, when an upward force acts on the rear end of the upper rail 70 in this way, a moment force for forward rotation (rotation in the direction in which the seat 10 tilts forward) acts at the position D, which is the rear end position of the lower rail 60, on the upper rail 70.

[0059] The moment force of the forward rotation increases as the distance between the rear end of the upper rail 70 and the position D on the upper rail 70 increases. That is, in such a case, when the seat 10 moves to the rearmost position, the moment force of the forward rotation acting on the position D on the upper rail 70 becomes the largest.

[0060] FIG. 7 is a schematic perspective view showing an enlarged periphery of the seat rail 50 shown in FIG. 5. That is, FIG. 7 is also a schematic perspective view showing the case where the seat 10 is in the rearmost position. In the present embodiment, in order to prevent the upper rail 70 from being deformed by such a moment force of the forward rotation, the reinforcing member 90 is provided in a predetermined range in the front-rear direction including the position D when the seat 10 moves to the rearmost position.

[0061] If the reinforcing member 90 is provided in a predetermined range in the front-rear direction including the position D when the seat 10 moves to the rearmost position, the rear end position of the reinforcing member 90 is not particularly limited.

[0062] For example, the rear end position of the reinforcing member 90 may be set at the same position as the rear end of the upper rail 70. In such a case, if the upper rail 70 is displaced rearward with respect to the lower rail 60, the reinforcing member 90 is provided at the position D on the upper rail 70 regardless of the position of the seat 10.

[0063] Also, as described above, the moment force of the forward rotation increases as the distance between the rear end of the upper rail 70 and the position D on the upper rail 70 increases. Therefore, for example, when the upper rail 70 is slightly displaced rearward with respect to the lower rail 60, the moment force of the forward rotation acting on the position D on the upper rail 70 is weak, and deformation of the upper rail 70 hardly occurs.

[0064] Therefore, the rear end position of the reinforcing member 90 may be set, for example, at a position near the rear end of the upper rail 70, may be set based on, for example, the rigidity of the upper rail 70, or may be set based on, for example, the rigidity of the reinforcing member 90 itself.

[0065] According to such a seat rail 50, even when the upper rail 70 is displaced rearward with respect to the lower rail 60 and a forward moment force acts on the position D on the upper rail 70, the deformation of the upper rail 70 is suppressed by the resistance force based on the rigidity of both the upper rail 70 and the reinforcing member 90. That is, even when the upper rail 70 and the lower rail 60 are in an offset state, it is possible to prevent the upper rail 70 from falling off the lower rail 60.

[0066] Note that the specific configuration shown in this embodiment is an example, and the aspects of the present invention are not limited to the configurations shown in the respective embodiments.

[0067] In this embodiment, when a moment force of forward rotation acts on the position D on the upper rail 70, at the rear end of the lower rail 60, the upper rail 70 tends to separate from the lower rail 60. Therefore, the flange 76 of the upper rail 70 and the flange 66 of the lower rail 60 are engaged with each other via the rolling element 80, and a downward force acts on the flange 76.

[0068] If the downward warping of the flange 76 is prevented at the position D on the upper rail 70, then at that position D, the lower part of the upper rail 70 is prevented from warping outward, and the opening of the upper rail 70 is prevented from further opening. Also, from this, if the downward warping of the flange 76 is prevented at the position D on the upper rail 70, then at the rear end of the lower rail 60, the disengagement of the engagement between the upper rail 70 and the lower rail 60 is prevented. Therefore, the reinforcing member 90 may be configured to include at least the flange 96, or may be configured to include at least the side wall 94 and the flange 96.

[0069] FIG. 8 is a schematic cross-sectional view showing a cross-section of a seat rail 50 according to a modified example of this embodiment. Note that the cross-section of FIG. 8 corresponds to the B cross-section of FIG. 2. For example, the upper wall 92 of the reinforcing member 90 may be located above the support portion 22 of the leg portion 16.

[0070] In this case, the upper wall 92 of the reinforcing member 90 is in contact with the upper surface of the support portion 22 of the leg portion 16, and the reinforcing member 90 encloses the support portion 22 of the leg portion 16. Further, in this case, the concave portion 22a of the support portion 22 may be omitted.

[0071] Also, regarding the reinforcing member 90, it may be omitted from either the right seat rail 50R or the left seat rail 50L according to the type of the seat belt 40. As shown in FIG. 1, the seat belt 40 is a three-point seat belt, and the connection point P with the seat belt 40 of the seat 10 is located on the right side of the seat 10.

[0072] Therefore, when the seat belt 40 is pulled by the seated person trying to move forward, an upward force mainly acts on the upper rail 70 of the right seat rail 50R. On the other hand, a smaller upward force acts on the upper rail 70 of the left seat rail 50L compared to the upper rail 70 of the right seat rail 50R. Therefore, in this case, at least the right seat rail 50R among the right seat rail 50R and the left seat rail 50L preferably includes the reinforcing member 90.

[0073] When the connection point P with the seat belt 40 of the seat 10 is located on the left side of the seat 10, an upward force mainly acts on the upper rail 70 of the left seat rail 50L. On the other hand, a smaller upward force acts on the upper rail 70 of the right seat rail 50R compared to the upper rail 70 of the left seat rail 50L. Therefore, in this case, at least the left seat rail 50L among the right seat rail 50R and the left seat rail 50L preferably includes the reinforcing member 90.

[0074] In addition, when the seat belt 40 is a two-point seat belt or a four-point seat belt, there are two or more connection points P between the seat belt 40 of the seat 10. One connection point P is located on the right side of the seat 10, and the other connection point P is located on the left side of the seat 10. Further, the seat belt 40 extends across the left and right sides of the seat 10 and covers the seated person.

[0075] In such a case, a similar upward force acts on the upper rails 70 of both the right seat rail 50R and the left seat rail 50L. Therefore, when the seat belt 40 is a two-point seat belt or a four-point seat belt, it is preferable that both the right seat rail 50R and the left seat rail 50L are provided with the reinforcing member 90.

[0076] In addition, in the present embodiment, a vehicle is cited as an example of a vehicle, and the seat rail 50 corresponding to the vehicle seat has been described. However, the configuration of the seat rail of the present invention is also applicable to seat rails of vehicles other than vehicles, for example, vehicles such as trains, ships, and airplanes.

Explanation of reference numerals

[0077] 10 Seat 50 Seat rail 50R Right seat rail 50L Left seat rail 60 Lower rail 70 Upper rail 90 Reinforcing member

Claims

【Claim 1】 A seat rail that supports a vehicle seat so as to be movable in the front-rear direction, A lower rail that extends in the front-rear direction, is fixed to the attachment destination of the seat, and has a hat-shaped cross section that opens upward, An upper rail that extends in the front-rear direction, is fixed to the seat, has a C-shaped cross section that opens downward, and is slidably engaged with the lower rail in the front-rear direction, A reinforcing member that has a C-shaped cross section that opens downward and covers the upper rail, and is fitted on the outside of the upper rail so as to reinforce at least the opening peripheral edge of the upper rail, The seat rail, wherein the reinforcing member is provided in a predetermined range in the front-rear direction including the rear end position of the lower rail when the seat is moved to the rearmost position.

Images