JP6495688B2 - Seat back frame and vehicle seat - Google Patents

Description

  The present invention relates to a seat frame for a vehicle seat, and more particularly to a seat frame that is lighter than conventional products.

  In order to reduce the weight of a vehicle seat, it is generally considered to reduce the thickness of each part of the seat frame. However, as the thickness of each part of the seat frame is reduced, the rigidity of the part decreases. On the other hand, when securing rigidity in the seat frame, it is conceivable that the cross-sectional structure of the portion where the rigidity or the like should be secured is a closed cross-sectional structure. For example, in the seat frame described in Patent Document 1, the side frame of the seat back frame has a closed cross-sectional structure.

JP 2014-88133 A

  The seat frame described in Patent Document 1 will be described in detail. The side frame (strictly speaking, the side frame of the seat back frame) has a closed cross-sectional structure from the upper end to the lower end. In such a configuration, although it is possible to ensure the rigidity of the side frame, it is difficult to sufficiently reduce the weight of the seat frame. Therefore, as a configuration for ensuring both rigidity and weight reduction, it is conceivable that a closed cross-section structure portion and an open cross-section structure portion coexist in the side frame. However, if the cross-sectional shape suddenly changes at the boundary portion between the closed cross-section structure portion and the open cross-section structure portion, problems such as significant reduction in rigidity and stress concentration may occur at the boundary portion.

  Some seat frames include a frame (connection frame) for connecting the side frames. In such a seat frame, when the closed cross-section structure portion and the open cross-section structure portion coexist in the side frame, the connection frame is appropriately attached to the side frame while considering the positional relationship between the connection frame and the side frame. Is required.

  In addition, other members, for example, a supporting member for supporting an occupant or a bundling attachment member for attaching a bundling of an airbag may be attached to the side frame. When the above-mentioned member is attached to the side frame in a configuration in which the closed cross-section structure portion and the open cross-section structure portion coexist in the side frame, it is required to be attached at a suitable position for smooth attachment work. .

Accordingly, the present invention has been made in view of the above-described problems, and an object thereof is to provide a seat frame capable of appropriately coexisting a closed cross-section structure portion and an open cross-section structure portion in a side frame. There is.
Another object of the present invention is to appropriately attach a connecting frame for connecting the side frames to the side frame in which the closed cross-section structure portion and the open cross-section structure portion coexist appropriately. It is to provide a seat frame.
A third object of the present invention is to attach a support member for supporting an occupant and a webbing of an airbag to a side frame in which a closed cross-section structure portion and an open cross-section structure portion coexist appropriately. An object of the present invention is to provide a seat frame capable of appropriately attaching a bundling attachment member.

According to the seat back frame of the present invention, the subject is a seat back frame having side frames provided at both ends in the width direction of the vehicle seat, wherein the side frame extends in the extending direction of the side frame. A closed cross-section structure portion in which a cross section intersecting with the extending direction is a closed cross-section structure, and a portion continuous with the closed cross-section structure portion in the extending direction, wherein the cross section is an open cross section An open cross-section structure portion having a structure, and a gap formed by discontinuation of a continuous portion in the cross-section of the open cross-section structure portion is the extending direction of the open cross-section structure portion than said adjacent region located in a position adjacent to the closed cross section, have become greater at spaced areas located in the extending direction at a position away from the closed cross section in, A baffle attachment member for attaching a baffle of an airbag is attached to the side frame, and in the front-rear direction of the vehicle seat, the attachment position of the baffle attachment member is on the closed cross-section structure and the side frame. This is solved by being a position between the provided recess .

  In the seat frame of the present invention configured as described above, the closed cross-section structure portion and the open cross-section structure portion coexist in the side frame. In addition, the gap formed by the interruption of the continuous portion in the cross section of the open cross-section structure portion is located at a position farther from the closed cross-section structure portion than the adjacent region in the position adjacent to the closed cross-section structure portion. It is larger in the separated area. That is, the degree of opening in the cross section of the open cross-section structure portion is larger in the separated region than in the adjacent portion. With such a configuration, it is possible to suppress a sudden change in the cross-sectional shape at the boundary portion between the closed cross-sectional structure part and the open cross-sectional structure part in the side frame, and to reduce the rigidity caused by the rapid change in the cross-sectional shape. It is possible to suppress stress concentration.

In the above seat back frame, it is preferable that the baffle attachment member is attached to the side frame at a plurality of positions sandwiching the recess .

In the above seat back frame, the baffle attachment member may be attached to the side frame at a plurality of positions sandwiching the recess in the extending direction of the side frame .

In the above seat back frame, the baffle attachment member may be attached to the side frame at a position surrounded by the recess .

Further, in the above seat back frame, in order to support an occupant, a support member that is laid between the side frames in the width direction is attached to the side frame, and the side frame is a part of the vehicle seat. An engagement hole for hooking an end of the support member at a position between the closed cross-sectional structure and the recess in the extending direction of the side frame, behind the attachment position of the baffle attachment member in the front-rear direction. It should be provided .

In the above seat back frame, the baffle attachment member is attached to the side frame by being inserted into a plurality of insertion holes provided in the side frame, and in the vertical direction of the vehicle seat, A second hole may be provided between the plurality of insertion holes .

In the seat back frame, the second hole may be provided in the recess .

In the seat back frame, the second hole may have a diameter larger than that of the engagement hole .

In the above seat back frame, the concave portion may be provided above and below the second hole in the vertical direction of the vehicle seat .

Further , according to the vehicle seat of the present invention, the subject is a seat cushion attached to an upper rail that is slidable along a lower rail fixed to a vehicle body floor, and a reclining device with respect to the seat cushion. And a headrest supported by an upper end portion of the seatback, wherein the seatback is provided at both ends in the width direction of the vehicle seat. A side frame and a connecting frame for connecting the side frames, wherein the side frame forms one end in the extending direction of the side frame, and a cross section intersecting the extending direction is a closed cross-sectional structure A closed cross-section structure portion, and a portion continuous with the closed cross-section structure portion in the extending direction, wherein the cross section is an open cross section An open cross-section structure portion, and a gap formed by breaking a continuous portion in the cross-section of the open cross-section structure portion is the extending direction of the open cross-section structure portion In the separation region located at a position away from the closed cross-section structure portion in the extending direction, than in the adjacent area located at a position adjacent to the closed cross-section structure portion in FIG. A baffle attachment member for attachment is attached to the side frame, and in the front-rear direction of the vehicle seat, the attachment position of the baffle attachment member is a closed section structure and a recess provided in the side frame. It is solved by being a position between.

In addition, according to the seat back frame of the present invention, the subject is a seat back frame having side frames provided at both ends in the width direction of the vehicle seat, wherein the side frame is an extension of the side frame. One end portion in the extending direction, a closed cross-section structure portion in which a cross section intersecting with the extending direction is a closed cross-sectional structure, a portion continuous with the closed cross-section structure portion in the extending direction, and the cross section is An open cross-section structure portion having an open cross-section structure, and a baffle attachment member for attaching a baffle of an airbag is attached to the side frame, and the force in the front-rear direction of the vehicle seat The cloth attachment member is attached by a position between the closed cross-sectional structure and the recessed portion provided in the side frame.

Further , according to the vehicle seat of the present invention, the subject is a seat cushion attached to an upper rail that is slidable along a lower rail fixed to a vehicle body floor, and a reclining device with respect to the seat cushion. And a headrest supported by an upper end portion of the seatback, wherein the seatback is provided at both ends in the width direction of the vehicle seat. A side frame and a connecting frame for connecting the side frames, wherein the side frame forms one end in the extending direction of the side frame, and a cross section intersecting the extending direction is a closed cross-sectional structure A closed cross-section structure portion, and a portion continuous with the closed cross-section structure portion in the extending direction, wherein the cross section is an open cross section And a blanket attachment member for attaching a blanket of an airbag is attached to the side frame, and the blanket is attached in the front-rear direction of the vehicle seat. This is solved by the fact that the mounting position of the member is a position between the closed cross-sectional structure and the concave portion provided in the side frame.

According to the seat frame of the present invention, it is possible to suppress a sudden change in the cross-sectional shape at the boundary portion between the closed cross-section structure portion and the open cross-section structure portion in the side frame, and to reduce the rigidity due to the abrupt change in the cross-sectional shape. And stress concentration can be suppressed.
Further, according to the seat frame of the present invention, the gap in the adjacent region gradually increases as the distance from the closed cross-section structure portion increases, so that the change in the cross-sectional shape at the boundary portion between the closed cross-section structure portion and the open cross-section structure portion is further improved. It can be effectively suppressed.
Further, according to the seat frame of the present invention, it is possible to improve the strength of the separation region.
Further, according to the seat frame of the present invention, it is possible to arrange the connecting frames appropriately and to connect the side frames well by the connecting frames.
Further, according to the seat frame of the present invention, the connecting frame is connected to the closed cross-section structure portion by joining the portion of the second extension portion that enters the inside of the one end portion in the extending direction of the closed cross-section structure portion to the closed cross-section structure portion. It becomes possible to attach the frame more appropriately.
Further, according to the seat frame of the present invention, it is possible to improve the rigidity of the side frame by setting the length of the adjacent region having lower rigidity among the adjacent regions to be shorter.
Further, according to the seat frame of the present invention, it is possible to appropriately attach the support member to the side frame.
In addition, according to the seat frame of the present invention, it is possible to appropriately attach the webbing attachment member to the adjacent region of the side frame.
In addition, according to the seat frame of the present invention, it is possible to attach the webbing attachment member by effectively using the space in the adjacent region.
In addition, according to the seat frame of the present invention, it is possible to appropriately attach the webbing attachment member to the separation region of the side frame.
Further, according to the seat frame of the present invention, when the baffle attachment member is appropriately attached to the separation region of the side frame, it is effectively avoided that a part of the separation region interferes with the baffle attachment member. It becomes possible.
In addition, according to the seat frame of the present invention, when the load is input at the time of the vehicle rear-end collision, the side frame is deformed from the fragile portion as a base point and the impact is exerted while the reinforcing effect by the reinforcing portion is more effectively exhibited. Can be relaxed.

1 is an overall view of a vehicle seat according to an embodiment of the present invention. It is a figure when the seat frame which concerns on one Embodiment of this invention is seen from diagonally forward. It is a figure when the seat frame which concerns on one Embodiment of this invention is seen from diagonally back. It is a schematic cross section which shows the location where the pillar guide is welded in a connection frame. It is a figure when the side frame which concerns on one Embodiment of this invention is seen from the side. It is a figure when one part which comprises a side frame is seen from the side. It is a figure when the other parts which comprise a side frame are seen from the side. It is a figure when the side frame which concerns on one Embodiment of this invention is seen from diagonally forward. It is a figure which shows the AA cross section in FIG. It is a figure which shows the BB cross section in FIG. It is a figure which shows CC cross section in FIG. It is a figure which shows the DD cross section in FIG. It is a figure which shows a 1st modification. It is a figure which shows a 2nd modification. It is a figure which shows a reclining apparatus and its attachment components.

  Hereinafter, an embodiment of the present invention will be described. The embodiment described below is merely an example for facilitating the understanding of the present invention, and does not limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes the equivalents thereof. Furthermore, in the following description, the contents regarding the material, shape, and size of each device and its component parts are merely one specific example, and do not limit the present invention. That is, the material, shape, and size of each device and its component parts can be freely designed as long as they satisfy the specific matters of the present invention.

  Further, in the following description, the “front-rear direction” means the front-rear direction of the vehicle seat, and specifically, a direction that coincides with the traveling direction of the vehicle. The “width direction” means the width direction of the vehicle seat, and specifically, is a direction that coincides with the vehicle width direction (left-right direction).

  Further, the following description assumes that the vehicle seat is in a use state (a state in which a seated person can be seated), unless otherwise specified. That is, in the following description, the posture and position of each part of the vehicle seat and the positional relationship with other members are the contents when the vehicle seat is in use.

<< Basic configuration of vehicle seat and seat frame >>
First, the basic configuration of a vehicle seat (hereinafter, this seat S) according to the present embodiment and a basic configuration of a seat frame F constituting the skeleton thereof will be described with reference to FIGS. As shown in FIG. 1, the seat S includes a seat back S1, a seat cushion S2, and a headrest S3. The seat back S1 and the seat cushion S2 are configured by placing the pad material P on the seat frame illustrated in FIGS. 2 and 3 and covering the surface of the pad material P with the skin material W. The headrest S3 is configured by arranging a pad material P on a core material (not shown) and covering the surface of the pad material P with a skin material W. A pair of headrest pillars (not shown) extending downward are provided below the headrest S3. The headrest S3 is supported by the upper end of the seat back S1 (strictly speaking, the seat back frame F1) via the pair of headrest pillars.

  2 and 3, the seat S includes a seat back frame F1 included in the seat back S1 and a seat cushion frame F2 included in the seat cushion S2. The seat cushion frame F2 is connected to the upper rail RU of the slide rail device R disposed below the seat cushion frame F2. With this configuration, when the upper rail RU moves along the lower rail RL fixed to the vehicle body floor, the entire seat S including the seat cushion frame F2 slides.

  In the present embodiment, the seat cushion frame F2 is connected to the upper rail RU via the rotation link XL as shown in FIG. The rotation link XL is a link member disposed on both sides of the seat cushion S2 in the width direction, and rotates about a rotation axis along the width direction. And the position of seat cushion S2 in the up-and-down direction comes to be adjusted because rotation link XL rotates while rotating with seat cushion S2.

  Further, the lower end portion of the seat back frame F1 is connected to the rear end portion of the seat cushion frame F2 via the reclining device 80. By this reclining device 80, the seat back S1 including the seat back frame F1 is coupled to the seat cushion S2 in a state in which an inclination angle with respect to the seat cushion S2 can be adjusted. That is, the seat back S1 can rotate relative to the seat cushion S2 about the reclining shaft 81 along the width direction.

  And this seat S differs from the conventional general vehicle seat in the structure of a seat frame. Hereinafter, the configuration of the seat back frame F1 as the seat frame included in the seat S will be described in detail. The configuration described below (particularly the structure of the side frame 10) is not applicable only to the seat back frame F1, but can also be applied to the seat cushion frame F2.

<< Detailed configuration of seat back frame >>
The configuration of the seat back frame F1 included in the seat S will be described in detail with reference to FIGS. 2 and 3 and FIGS. As shown in FIG. 2, the seat back frame F1 forms a square frame when the seat frame F is viewed from the front. Further, the seat back frame F1 is lighter than a seat back frame included in a conventional general vehicle seat. More specifically, a material that is lighter than a material used for a conventional seat back frame is used as a material that constitutes the seat back frame F1 (for example, a steel plate that constitutes a side frame 10 described later). . Further, when the parts constituting the seat back frame F1 are fastened and connected, the parts are fastened and connected by laser welding without using fasteners such as bolts, nuts and screws. By adopting such a configuration, the seat back frame F1 according to the present embodiment is lighter.

  The structure of the seat back frame F1 will be described. As shown in FIGS. 2 and 3, the seat back frame F1 has a pair of side frames 10 provided at both ends in the width direction. Further, as shown in the figure, the seat back frame F1 has an upper frame 30 that is connected to the upper end portions of the side frames 10 to connect the side frames 10 together. Furthermore, the seatback frame F1 has a lower member frame 50 that connects between the side frames 10 by being attached to the lower ends of the side frames 10, as shown in FIG. Further, an S spring 60 is installed between the side frames 10 as a support member that supports the back of the passenger from behind.

Hereinafter, the upper frame 30, the lower member frame 50, and the side frame 10 will be described in this order.
The upper frame 30 is a part formed in a downward U-shape when viewed from the front, and corresponds to a connecting frame. Moreover, in this embodiment, the upper frame 30 is comprised by the metal hollow pipe members. However, it is not limited to this, The upper frame 30 may be comprised with the solid member. Further, as shown in FIG. 2, the upper frame 30 includes a horizontal portion 31 as a first extending portion extending in the width direction, and a second extending portion positioned on both sides of the horizontal portion 31 in the width direction. And a downwardly extending portion 32. Each downward extending portion 32 extends downward toward the side frame 10, and the lower end portion 32 a is joined to the upper portion of the side frame 10.

  In addition, the part (henceforth, skew part 32b) located below the lower end part 32a among the downward extension parts 32 is skewed so that it may spread outward in the width direction as it goes below. As shown in FIGS. 2 and 3, a connecting plate 33 extending in the width direction is installed between the lower end portions of the skewed portion 32b. Of the connecting plate 33, both ends in the width direction are fixed to the skewed portion 32b by laser welding. Further, both end portions in the width direction of the connecting plate 33 are curved so as to be displaced backward from the portion fixed to the skewed portion 32b toward the inner side in the width direction.

  A square cylindrical pillar guide 34 that supports the headrest pillar is attached to the front surface of the horizontal portion 31 of the upper frame 30. A pair of pillar guides 34 are provided at intervals in the width direction. Moreover, the part in which the pillar guide 34 is attached among the horizontal parts 31 is crushed so that the front surface may become a plane. A pillar guide 34 is fixed to a portion that is flattened and flattened.

  When the cross section perpendicular to the width direction of the portion where the pillar guide 34 is fixed in the horizontal portion 31 is seen, as shown in FIG. 4, a portion that is raised upward and downward by being crushed (hereinafter referred to as a raised portion). 31a) is formed. In the present embodiment, the pillar guide 34 is fixed using the raised portion 31a. More specifically, the raised portion 31a and the pillar guide 34 are laser welded by irradiating a welding laser from the rear of the raised portion 31a in a state where the front surface of the raised portion 31a and the rear surface of the pillar guide 34 are in contact with each other. Yes. Incidentally, in FIG. 4, the protruding portion 31 a is illustrated somewhat larger than the actual size for easy understanding of the description.

  Next, the lower member frame 50 will be described. The lower member frame 50 is formed by processing a sheet metal, and is spanned between lower end portions of the side frames 10 (strictly, between lower end portions of a rear wall portion 14 of an outer part 11 described later). Further, the upper edge portion and the lower edge portion of the lower member frame 50 are each bent forward to form a flange.

  Next, the side frame 10 will be described with reference to FIGS. 5A is a view showing the side frame 10 according to the present embodiment, and FIGS. 5B and 5C are views showing the respective parts constituting the side frame 10, both of which are viewed from the inner side in the width direction. It is a time figure.

  As shown in FIG. 5A, the side frame 10 has a spindle-shaped outer shape when viewed from the side. That is, when the side frame 10 is viewed from the side, the front end portion of the side frame 10 bulges out in a circular arc shape from a midway position in the vertical direction. Note that when the seat S is in use (more strictly speaking, when the seat back S1 is at the reference position), the side frame 10 is along a direction slightly inclined (backward inclined) with respect to the vertical direction. It extends for a long time. Incidentally, hereinafter, the extending direction of the side frame 10 is referred to as a “frame extending direction”.

  Further, a lower end portion 32 a of the downward extending portion 32 of the upper frame 30 is joined to one end portion (upper end portion) of the side frame 10 in the extending direction. Here, in a state where the lower end portion 32a is joined to the upper end portion of the side frame 10, the extending direction of the downward extending portion 32 substantially coincides with the frame extending direction. In this sense, it can be said that the frame extending direction corresponds to the extending direction of the downward extending portion 32.

  In addition, in this seat S, the length of the part joined to the upper end part of the side frame 10 among the lower end parts 32a of the downward extension part 32 is short compared with the conventional vehicle seat. This is to make the seat S lighter than the conventional vehicle seat. In the present embodiment, the thickness of the steel plate constituting the side frame 10 is smaller than the thickness of the pipe constituting the upper frame 30.

  Moreover, in this embodiment, the side frame 10 is comprised by the thin steel plate, More specifically, the ultra high strength steel plate of thickness 1mm or less. Furthermore, the side frame 10 according to the present embodiment is configured by joining a plurality of frame pieces, specifically, two frame pieces. More specifically, each side frame 10 includes an outer part 11 illustrated in FIG. 5B and an inner part 12 illustrated in FIG. 5C as components. All of these parts are formed by processing an ultra-high strength steel sheet.

  The outer part 11 corresponds to one frame piece among a plurality of frame pieces constituting the side frame 10, and mainly constitutes a portion on the outer side in the width direction in the side frame 10. The inner part 12 corresponds to another frame piece, and mainly configures an inner portion in the width direction in the side frame 10. As shown in FIG. 6, the outer part 11 and the inner part 12 constitute a side frame 10 by being joined by laser welding in a state where a part thereof overlaps. In FIG. 6, the welding marks when laser welding is performed are shown by thick broken lines.

  Hereinafter, the structure of the side frame 10 will be described in more detail with reference to FIGS. 6 to 10 together with FIGS. 3 and 5A to 5C. First, in describing the structure of the side frame 10, the configuration of each of the outer part 11 and the inner part 12 will be described.

  The outer part 11 has a substantially U-shaped cross section that intersects with the frame extending direction, and includes a side wall portion 13 and a rear wall portion 14 as shown in FIGS. The side wall part 13 is a part located in the edge part of the width direction outer side in the side frame 10. As shown in FIG. And the end surface of the side wall part 13 prescribes | regulates the end surface of the width direction outer side of the side frame 10. As shown in FIG. That is, the outer shape of the side wall portion 13 corresponds (substantially coincides) with the outer shape of the side frame 10 as can be seen by comparing FIGS. 5A and 5B. Further, the front end portion of the side wall portion 13 includes a flange portion 13a formed by being bent at a substantially right angle toward the inner side in the width direction. The flange portion 13a is formed in a wide range from the middle portion of the side wall portion 13 to the lower end portion in the frame extending direction.

  In addition, a plurality of rectangular holes and circular holes are formed in the side wall portion 13 as shown in FIG. 5B. In these holes, an end portion of an S spring 60 described later and a webbing attachment clip 70 are inserted and engaged. Details regarding the holes will be described later.

  Further, an attachment hole 13b for attaching the reclining device 80 is formed in the lower portion of the side wall portion 13 as shown in FIG. 5B. A reclining device 80 is attached to the side wall portion 13 so that the reclining shaft 81 passes through the attachment hole 13b. In the present embodiment, a plurality of attachment parts are used for attaching the reclining device 80 to the side wall portion 13. The attachment parts of the reclining device 80 will be described later.

  The rear wall portion 14 is a portion provided so as to be substantially orthogonal to the rear end portion of the side wall portion 13 and extends toward the inner side in the width direction as shown in FIG. The rear wall portion 14 extends long in the frame extending direction, and the end positions (upper end position and lower end position) of the rear wall portion 14 in the same direction are substantially aligned with the end position of the side wall portion 13. Moreover, the edge part of the width direction inner side of the rear wall part 14 is equipped with the flange part 14a formed by bending at a substantially right angle toward the front. The flange portion 14a is formed in a wide range from the upper end portion to the lower end portion of the rear wall portion 14 in the frame extending direction. As shown in FIG. 6, the flange portion 14 a is interrupted at a position directly above the lower member frame 50 in the frame extending direction for the convenience of attaching the lower member frame 50 to the lower end portion of the rear wall portion 14.

  Further, as shown in FIG. 3, a bead (hereinafter referred to as a rear wall bead 14 b) formed along the frame extending direction is formed on the rear surface of the rear wall portion 14. The rear wall bead 14b is provided to improve the rigidity of the rear wall part 14 (particularly, the rigidity against a load acting in the front-rear direction), and the center part in the width direction of the rear wall part 14 is recessed forward. Is formed. In the present embodiment, the rear wall bead 14 b is formed such that its lower end reaches a position directly above the lower member frame 50.

  As shown in FIG. 5C, the inner part 12 has a curved shape in accordance with the outer shape of the side frame 10, and has an upper part 15, a part central part 16, and a lower part 17 as shown in FIG. . The part upper part 15 constitutes the upper end part of the inner part 12, and as shown in FIG. 7, the cross section intersecting with the frame extending direction is substantially U-shaped. As shown in FIGS. 6 and 7, the parts upper part 15 constitutes a closed cross-section structure part 10 a of the side frame 10 by being combined and joined to the upper part of the outer part 11. The closed section structure portion 10a will be described in detail later.

  The part center part 16 constitutes a part adjacent to the lower end part of the part upper part 15 in the inner part 12, and extends so as to fall obliquely forward from the lower end of the part upper part 15. Moreover, as shown in FIG. 8, the cross section which cross | intersects the frame extension direction of the parts center part 16 has comprised substantially V shape. As shown in FIGS. 6 and 7, the center part 16 of the part constitutes an open cross-section structure part 10b of the side frame 10 by being combined with and joined to the middle part of the outer part 11 in the frame extending direction. ing. Strictly speaking, the part center part 16 is joined to the front end part of the side wall part 13 of the outer part 11, so that the position adjacent to the closed cross-section structure part 10a in the frame extending direction in the open cross-section structure part 10b. This constitutes the adjacent region 10x. The open section structure portion 10b and the adjacent region 10x will be described in detail later.

  The part lower part 17 constitutes a part of the inner part 12 positioned below the part center part 16, and extends from the lower end of the part center part 16 so as to be curved while being curved in an arc shape. Moreover, as shown in FIG. 9, the cross section which cross | intersects the frame extension direction of the parts lower part 17 has comprised the substantially S shape. The lower part 17 is formed to be somewhat narrower than the upper part 15 in the front-rear direction. As shown in FIGS. 6, 9, and 10, the part lower portion 17 is combined with the lower part of the outer part 11 to constitute an open cross-section structure portion 10 b of the side frame 10. Strictly speaking, the part lower part 17 is joined to the front end part of the side wall part 13 of the outer part 11, so that the part lower part 17 is located at a position separated from the closed cross-section structure part 10a in the frame extending direction in the open cross-section structure part 10b. The existing separation area 10y is configured. In particular, the part lower portion 17 constitutes only the front end portion of the separation region 10 y in the side frame 10. The separation region 10y will be described later in detail.

  Next, the structure of the side frame 10 will be described. As shown in FIG. 6, a closed cross-section structure portion 10 a is formed at the upper end portion of the side frame 10. As shown in FIG. 7, the closed cross-section structure portion 10 a is a portion in which a cross section that intersects the frame extending direction has a closed cross-section structure.

  And the lower end part 32a of the downward extension part 32 of the upper frame 30 has entered inside the upper end part (one end part in a frame extension direction) of the closed cross-section structure part 10a, and the said lower end part 32a is further closed cross-section structure. It is joined to the part 10a. That is, the end part located in the same side as the downward extension part 32 in the frame extension direction among the side frames 10 comprises the closed cross-section structure part 10a. On the other hand, the downward extending portion 32 enters the inside of the upper end portion of the closed cross-section structure portion 10a and is joined to the upper end portion. As a result, the upper frame 30 is appropriately assembled to the side frame 10, and as a result, the side frames 10 are well connected to each other by the upper frame 30. In the present embodiment, the downward extending portion 32 and the upper end portion of the closed cross-section structure portion 10a are joined by irradiating a welding laser from the outside of the upper end portion.

  On the other hand, as described above, in the present sheet S, for the purpose of reducing the weight, the length (hereinafter, the joining length) of the portion of the downward extending portion 32 joined to the upper end portion of the side frame 10 is reduced. It is shorter than conventional vehicle seats. Here, if the said joining length is shortened, the support rigidity of the side frame 10 will be impaired by that much. Here, the support rigidity of the side frame 10 means the stability of the support state of the side frame 10 when an external force is applied to the side frame 10.

  On the other hand, in this embodiment, the upper end part of the side frame 10 to which the downward extension part 32 is joined is the closed cross-section structure part 10a. In this closed section structure portion 10a, the support rigidity is ensured because of the closed section structure. Further, as shown in FIG. 6, the closed cross-section structure portion 10 a extends so that the lower end of the closed cross-section structure portion 10 a is positioned below the lower end of the lower extension portion 32 in the frame extending direction. That is, a portion of the side frame 10 that is located below the downward extension portion 32 (that is, a portion that is not joined to the downward extension portion 32) has a closed cross-section structure portion 10a, thereby supporting rigidity. Is secured.

  As described above, in the present embodiment, the upper end portion of the side frame 10 is used as the closed cross-section structure portion 10a, the lower extension portion 32 of the upper frame 30 is joined to the closed cross-section structure portion 10a, and the closed cross-section structure portion is further formed. 10 a is extended below the lower end of the downward extending portion 32. As a result, it is possible to compensate for the support rigidity that is lost by shortening the joining length.

  In addition, in this embodiment, as shown in FIG. 7, the closed cross-section structure part 10a is formed by joining the upper part of the outer part 11 and the parts upper part 15 of the inner part 12 by the laser welding. Has been. More specifically, in the upper part of the outer part 11, the flange part 14 a of the side wall part 13 and the rear wall part 14 overlaps the part upper part 15 of the inner part 12. The upper part of the outer part 11 and the part upper part 15 of the inner part 12 are joined by irradiating the overlapping part with a welding laser along the frame extending direction. As described above, if the two parts are overlapped to form the closed cross-section structure portion 10a, the strength of the closed cross-section structure portion 10a can be further increased, and the support rigidity of the side frame 10 can be further ensured.

  In the present embodiment, the thickness of the steel plate constituting the side frame 10 is smaller than the thickness of the pipe constituting the upper frame 30. Thereby, even if the closed length structure portion 10a is extended below the lower end of the downward extending portion 32 while the joining length is shortened, an increase in the weight of the side frame 10 is suppressed (specifically, the conventional product) Can be made lighter).

  By the way, if the whole side frame 10 is made into a closed cross-section structure, the weight of the side frame 10 will increase correspondingly. For this reason, in this embodiment, only the upper end part of the side frame 10 is set as the closed cross-section structure part 10a, and the part located below it is set as the open cross-section structure part 10b. Here, the open cross-section structure portion 10b is a portion in the side frame 10 that is continuous with the closed cross-section structure portion 10a in the frame extending direction and has a cross section that intersects the frame extending direction. That is, in the open cross-section structure portion 10b, as shown in FIGS. 8 and 9, a gap Q is formed by interruption of a continuous portion in the cross section.

  As described above, in the present embodiment, only the upper end portion of the side frame 10 is the closed cross-section structure portion 10a, so that the supporting rigidity of the side frame 10 is ensured and the weight of the seat back frame F1 including the side frame 10 is further increased. It is possible to reduce the weight.

  Furthermore, in the present embodiment, the open cross-section structure portion 10b includes an adjacent region 10x located at a position adjacent to the closed cross-section structure portion 10a in the frame extending direction, and a separation region located at a position away from the closed cross-section structure portion 10a. And 10y.

  The adjacent region 10x is a region adjacent to the lower end portion (the other end portion in the frame extending direction) of the closed cross-section structure portion 10a in the open cross-section structure portion 10b. The adjacent region 10x is configured by joining by laser welding in a state where the central portion of the outer part 11 and the part central portion 16 of the inner part 12 overlap each other in the frame extending direction. More specifically, the flange portion 13 a of the side wall portion 13 of the central portion of the outer part 11 overlaps the part central portion 16 of the inner part 12. By irradiating the overlapping laser beam along the frame extending direction to the overlapping portion, the center portion of the outer part 11 and the part center portion 16 of the inner part 12 are joined. An adjacent region 10x is formed by the central portion of the joined outer part 11 and the part central portion 16 of the inner part 12.

  Further, as shown in FIG. 8, the adjacent region 10 x has a pair of end portions 10 s and 10 t located at positions adjacent to the gap Q among the continuous portions in the cross section. Further, as shown in FIG. 8, each of the pair of end portions 10s and 10t included in the adjacent region 10x extends so that the respective leading ends thereof are directed to the gap Q in the cross section.

  The separation region 10y is a region located below the adjacent region 10x in the open section structure portion 10b. The separation region 10y is configured by joining the lower part of the outer part 11 in the frame extending direction and the part lower part 17 of the inner part 12 by laser welding in an overlapping state. More specifically, in the lower part of the outer part 11, the flange part 13 a of the side wall part 13 overlaps the part lower part 17 of the inner part 12. The overlapping part is irradiated with a welding laser along the frame extending direction, whereby the lower part of the outer part 11 and the part lower part 17 of the inner part 12 are joined. A separated region 10 y is formed by the lower part of the joined outer part 11 and the lower part 17 of the inner part 12.

  Further, as shown in FIG. 9, the separation region 10 y has a pair of end portions 10 s and 10 t located at positions adjacent to the gap Q among the continuous portions in the cross section. Of the pair of end portions 10s, 10t included in the separation region 10y, the end portion 10s located on the front side is folded back in the front-rear direction as shown in FIG. That is, the end portion 10s located on the front side has two portions that overlap in the width direction (hereinafter, overlapping portions 10v and 10w). As described above, in the present embodiment, the strength of the open cross-section structure portion 10b including the separation region 10y is increased by folding back the end portion 10s located on the front side of the pair of end portions 10s and 10t included in the separation region 10y. It has been.

  In the present embodiment, among the pair of end portions 10s and 10t included in the separation region 10y, the end portion 10s positioned on the front side is folded back. However, the present invention is not limited to this, and the rear side portion is closer to the rear side. It is good also as turning up the edge part 10t located.

  Furthermore, as shown in FIG. 9, the end portion 10 s located on the front side forms a closed space C by joining the two overlapping portions 10 v and 10 w. More specifically, the end portion 10s positioned on the front side is folded back in the front-rear direction as described above, but is folded back in a bag shape particularly in the present embodiment. That is, in the folded back end portion 10s, the region at the rear is narrower than the region at the front, and the overlapping portions 10v and 10w are in contact with each other. The two overlapping portions 10v and 10w are joined by irradiating the two overlapping portions 10v and 10w that are in contact with each other with a laser for welding. As a result, the end portion 10s located on the front side forms a closed space C. As described above, in the present embodiment, since the end portion 10s positioned on the front side forms the closed space C, the strength of the open cross-section structure portion 10b including the separation region 10y is further increased.

  In joining the two overlapping portions 10v and 10w, a laser for welding is irradiated from the inner side in the width direction (in other words, of the two overlapping portions 10v and 10w, the overlapping portion 10w located on the inner side in the width direction). (Laser is irradiated to the laser).

  In the present embodiment, the two overlapping portions 10v and 10w are joined by laser welding, and the end portion 10s located on the front side forms the closed space C. However, the present invention is limited to this. It is not something. As shown in FIG. 11, the two overlapping portions 10v and 10w may be separated from each other with a space therebetween (that is, a configuration in which the end portion 10s located on the front side is not closed).

  By the way, in this embodiment, as shown in FIG. 6, the opening degree of the cross section in the adjacent region 10x of the open cross-section structure portion 10b increases as it goes downward. In other words, the pair of end portions 10s and 10t included in the adjacent region 10x are separated so as to be away from the closed cross-section structure portion 10a in the frame extending direction, and a larger gap Q is separated. Further, in this embodiment, as can be seen by comparing FIGS. 8 and 9, the gap Q (that is, the degree of opening of the cross section) in the cross section of the open cross section structure portion 10b is larger in the separated area 10y than in the adjacent area 10x. ing. With such a configuration, it is possible to suppress a sudden change in the cross-sectional shape at the boundary portion between the closed cross-section structure portion 10a and the open cross-section structure portion 10b. Thereby, it is possible to suppress a reduction in rigidity and stress concentration of the side frame 10 due to a sudden change in the cross-sectional shape.

  Furthermore, as described above, the gap Q in the adjacent region 10x gradually increases as the gap Q is away from the closed cross-section structure 10a in the frame extending direction. Thereby, it becomes possible to more effectively suppress a sudden change in the cross-sectional shape at the boundary portion between the closed cross-section structure portion 10a and the open cross-section structure portion 10b.

  The structure of the side frame 10 according to the present embodiment will be described in more detail. As shown in FIG. 5A, the length of the adjacent region 10x in the frame extending direction is shorter than the length of the closed cross-section structure portion 10a in the same direction. ing. That is, in the present embodiment, the adjacent region 10x having a lower rigidity than the closed cross-section structure portion 10a is configured to be shorter than the closed cross-section structure portion 10a in the frame extending direction. Thereby, in this embodiment, compared with the case where the adjacent area | region 10x is comprised so that it may become longer than the closed cross-section structure part 10a, the side frame 10 is more rigid.

  Further, as shown in FIGS. 2, 3 and 7, the side frame 10 is formed with a recess formed by being recessed inward in the width direction. This recessed part is formed in the side wall part 13 of the outer part 11 which comprises the side frame 10, more specifically, the center part of the side wall part 13 in a flame | frame extension direction, and the part equivalent to a lower half. As described above, in the present embodiment, the strength of the side frame 10 is increased by providing the recesses in the side wall portion 13. Note that the number of recesses provided in the side wall part 13 and the locations where the recesses are provided are not particularly limited.

  Incidentally, of the recesses formed in the side frame 10, a recess (hereinafter referred to as the first recess 20) formed in the central portion of the side wall portion 13 is a substantially triangular recess in a side view. Further, as can be seen by comparing FIGS. 5A, 5B and 5C, the first recess 20 is such that the upper end of the first recess 20 is positioned above the lower end of the closed cross-section structure portion 10a in the side frame 10. Is provided.

  By the way, when the concave portion is provided in the side frame 10, the section modulus of the portion where the concave portion is provided is reduced, and in particular, the portion changes significantly in the portion where the upper end of the concave portion is located. On the other hand, in this embodiment, the part in which the upper end of the 1st recessed part 20 is located in the side frame 10 becomes the closed cross-section structure part 10a. With such a configuration, it is possible to suppress a decrease in the section modulus in the portion of the side frame 10 where the upper end of the first recess 20 is located.

  Of the recesses formed in the side frame 10, a recess (hereinafter referred to as a second recess 21) formed in the lower half of the side wall portion 13 is an outer surface of the side wall portion 13 (surface outward in the width direction). Surface). Here, a part of the second concave portion 21 forms an end portion 10s positioned on the front side of the pair of end portions 10s and 10t included in the separation region 10y. Strictly speaking, of the two overlapping portions 10v and 10w formed by folding the end portion 10s, the overlapping portion 10v positioned on the outer side in the width direction is, as shown in FIG. Located in.

  And the overlapping part 10v located in the 2nd recessed part 21 is joined to the overlapping part 10w facing this by laser welding. As described above, in the present embodiment, one of the two overlapping portions 10v and 10w to be joined is located within the range where the strength of the second recess 21, that is, the side frame 10, is increased. Thereby, it becomes possible to ensure the joining strength when joining the two overlapping portions 10v, 10w by laser welding. Here, the joining strength means the stability of both contact states at the stage of joining the two overlapping portions 10v and 10w.

  Further, the lower half of the side wall portion 13 of the side frame 10 has a floating island-shaped bead portion (hereinafter referred to as a convex bead) surrounded by a second concave portion 21 as shown in FIGS. 22) is formed. The convex bead 22 corresponds to a reinforcing portion, and is provided at the lower end portion of the side frame 10 so that the rigidity of the side frame 10 (particularly, the rigidity with respect to the load input from the occupant to the upper portion of the seat back S1 at the time of a vehicle rear-end collision ) Is provided. Moreover, the convex bead 22 is formed by raising a predetermined part in the side frame 10 toward the outside, and is formed so as to extend linearly in the front-rear direction in this embodiment.

  In addition, the convex bead 22 is good to be formed so that the position of each part of the bead may be lowered toward the rear end. More preferably, the convex bead 22 is formed so as to extend in a direction along the input direction of the load input to the upper portion of the seat back S1 at the time of the rear collision of the vehicle. Moreover, in this embodiment, the convex bead 22 is formed at the same height as the end portion 10s on the folded side of the pair of end portions 10s, 10t included in the separation region 10y. More precisely, the formation position of the convex bead 22 is substantially the same as the two overlapping portions (overlapping portions 10v, 10w) in the folded end portion 10s in the frame extending direction. With such a positional relationship, in the present embodiment, the strength of the side frame 10 is effectively increased by combining the folding of the end 10 s and the formation of the convex beads 22.

  Moreover, about the convex bead 22, it is not limited to the structure provided in the side wall part 13, and as shown in FIG. When the configuration illustrated in FIG. 11 is described, a weakened portion 23 is formed along the width direction at the lower end portion of the rear wall portion 14. The fragile portion 23 is a portion that becomes a deformation base point when the side frame 10 is bent due to an impact load of a predetermined size or more applied at the time of rearward collision of the vehicle, and includes a hole portion, a concave portion, and the like. In addition, the weak part 23 is provided in the back position rather than the convex bead 22 provided in the side wall part 13. More specifically, as shown in FIG. 11, it may be formed at a position straddling the boundary portion (corner portion) between the side wall portion 13 and the rear wall portion 14. In the above configuration, when the second convex bead 22 extending in the direction intersecting the fragile portion 23 is provided in a portion of the rear wall portion 14 located above or below the fragile portion 23. Good.

<< About the S spring mounting position on the side frame >>
As shown in FIGS. 2 and 3, the seat back frame F <b> 1 according to the present embodiment includes an S spring 60 that is installed between the side frames 10 in the width direction. On the other hand, the S spring 60 extends while meandering in the vertical direction along the width direction. Further, the end portion of the S spring 60 in the extending direction is hooked in an engagement hole 13 x formed in the side wall portion 13 of the outer part 11 in the side frame 10. Thereby, the S spring 60 is attached to the side frame 10.

  Here, the position where the engagement hole 13x is formed will be described. As can be seen by comparing FIGS. 5A and 5C, the engagement hole 13x is formed at the same position as the adjacent region 10x in the frame extending direction. Further, the engagement hole 13x is formed between a pair of end portions 10s and 10t included in the adjacent region 10x in the front-rear direction. That is, in the present embodiment, the attachment position of the S spring 60 is the same position as the adjacent region 10x in the frame extending direction, and is a position away from the pair of end portions 10s and 10t included in the adjacent region 10x. Yes. Due to such a positional relationship, in the present embodiment, the S spring 60 is appropriately attached to the side frame 10 so as not to interfere with the pair of end portions 10s, 10t of the adjacent region 10x.

<< About the attachment position of the bundling attachment clip on the side frame >>
In the seat back frame F1 according to the present embodiment, a webbing attachment clip 70 illustrated in FIG. 10 is attached to the side frame 10 closer to the door of the vehicle. The baffle attachment clip 70 corresponds to a baffle attachment member and is a component for attaching a baffle of an airbag (not shown). On the other hand, in the side frame 10, rectangular insertion holes 13 y and 13 z for inserting the bundling attachment clips 70 are formed in the side wall portion 13 of the outer part 11. Then, as shown in FIG. 10, the webbing attachment clip 70 is attached to the side frame 10 by inserting a part of the webbing attachment clip 70 into the insertion holes 13 y and 13 z.

  In this embodiment, as shown in FIG. 5B, two insertion holes 13y and 13z are formed at different positions in the frame extending direction. Hereinafter, the formation positions of the respective insertion holes 13y and 13z will be described. In the following, the insertion hole 13y positioned higher in the frame extending direction is referred to as “upper insertion hole 13y”, and the insertion hole 13z positioned lower is referred to as “lower insertion hole 13z”. .

  The upper insertion hole 13y is formed at the same position as the adjacent region 10x in the frame extending direction, as can be seen by comparing FIGS. 5A and 5B. Further, the upper insertion hole 13y is formed at a position shifted from each of the pair of end portions 10s, 10t of the adjacent region 10x in the width direction. More specifically, the upper insertion hole 13y is formed at a position facing the front end 10s in the width direction of the pair of end portions 10s and 10t of the adjacent region 10x. That is, in the present embodiment, the attachment position of the bundling attachment clip 70 inserted into the upper insertion hole 13y is the same position as the adjacent region 10x in the frame extending direction, and a pair of end portions included in the adjacent region 10x The position is away from 10s and 10t. Due to such a positional relationship, in this embodiment, the webbing attachment clip 70 is appropriately attached to the side frame 10 so as not to interfere with the pair of end portions 10s and 10t included in the adjacent region 10x. In addition, a space is formed on the inner side in the width direction of the end portion 10s located on the front side of the pair of end portions 10s and 10t included in the adjacent region. In the present embodiment, the webbing attachment clip 70 is attached using such space effectively.

  In the present embodiment, as shown in FIG. 5B, the upper insertion hole 13y is a portion of the side wall portion 13 where the above-described recesses (the first recess 20 and the second recess 21) are not formed, That is, it is formed in a portion (non-recessed portion) located more outward in the width direction. Moreover, in this embodiment, the upper insertion hole 13y is located ahead of the engagement hole 13x formed for attaching the S spring 60, as shown in FIG. 5B. In other words, in the seat back frame F <b> 1 according to the present embodiment, the S spring 60 is disposed behind the baffle attachment clip 70 that is inserted into the upper insertion hole 13 y.

  The lower insertion hole 13z is formed at the same position as the separation region 10y in the frame extending direction, as can be seen by comparing FIGS. 5A and 5B. Further, the lower insertion hole 13z is formed in the vicinity of the folded back end portion (that is, the end portion 10s located on the front side) of the pair of end portions 10s, 10t of the separation region 10y. Yes. More specifically, as shown in FIG. 10, the end portion 10s has two portions (overlapping portions 10v and 10w) that are overlapped in the width direction when folded. On the other hand, the lower insertion hole 13z is formed behind the inner overlapping portion 10w of the two portions 10v and 10w. More specifically, as shown in FIG. 5A, the lower insertion hole 13z is formed immediately behind the inner overlapping portion 10w. Further, in the present embodiment, a portion of the inner overlapping portion 10w located immediately before the lower insertion hole 13z is cut away to form a relief portion 10u as shown in FIG. . The escape portion 10u is a portion formed to cross the bundling attachment clip 70 in the overlapping portion 102 on the inner side.

  That is, in the present embodiment, the attachment position of the bundling attachment clip 70 inserted into the lower insertion hole 13z is the same position as the separation region 10y in the frame extending direction, and one end portion of the separation region 10y has In 10 s, the position is away from the overlapping portion 10 w located on the inner side in the width direction. Due to such a positional relationship, in this embodiment, the webbing attachment clip 70 is appropriately attached to the side frame 10 so as not to interfere with the overlapping portion 10w.

  In addition, the baffle attachment clip 70 to be inserted into the lower insertion hole 13z is attached to the peripheral position of the overlapping portion 10w in the side frame 10. On the other hand, a notch-shaped escape portion 10u is formed in the overlapping portion 10w. This makes it possible to more effectively avoid interference with the overlapping portion 10w when attaching the bundling attachment clip 70 to be inserted into the lower insertion hole 13z to the side frame 10.

  In the present embodiment, of the pair of end portions 10s and 10t included in the separation region 10y, the folded end portion 10s is relatively short for the purpose of avoiding interference with the bundling attachment clip 70. ing. Further, the end portion 10s forms a closed space C by joining two overlapping portions 10v and 10w, but the above-described relief portion 10u is formed in the vicinity of the lower insertion hole 13z. As shown in FIG. 10, the closed space C is not opened. However, the present invention is not limited to this, and the formation position of the lower insertion hole 13z is shifted rearward from the position shown in FIG. 10, and the closed space C is formed in the vicinity of the lower insertion hole 13z. There may be.

  Further, in the present embodiment, the lower insertion hole 13z is a non-recessed portion in which the above-described recesses (first recess 20 and second recess 21) are not formed in the side wall portion 13 as shown in FIG. 5B. Is formed.

<< Installation of reclining device >>
In the present embodiment, the reclining device 80 is attached to the lower end portion of the seat back frame F <b> 1, more specifically, to the lower end portion of the side wall portion 13 of the outer part 11 constituting the side frame 10. More specifically, a mounting hole 13b for mounting the reclining device 80 is formed at the lower end of the side wall 13. As shown in FIG. 13, the mounting hole 13b has a substantially inverted keyhole shape when viewed from the side. That is, the lower part of the mounting hole 13b is circular, and the upper part is substantially rectangular.

  In the present embodiment, the first bracket 82 is interposed between the side wall 13 and the reclining device 80 in the width direction, and the reclining device 80 is attached to the side wall 13 via the first bracket 82. Yes. The first bracket 82 is made of a relatively thick steel plate, and as shown in FIG. 13, includes a substantially inverted keyhole-shaped base portion 82a and a protruding portion 82b protruding outward in the width direction from the upper end portion of the base portion 82a. Have. One end of the spiral spring 85 is locked to the overhanging portion 82b. That is, the urging force by the spiral spring 85 directly acts on the overhanging portion 82b.

  The base portion 82a includes a ring-shaped lower portion and a rectangular frame-shaped upper portion, and is welded to the outer surface (surface facing the width direction outer side) of the side wall portion 13. More specifically, the base portion is irradiated with a laser for welding from the inner side in the width direction than the side wall portion 13 in a state where the base portion 82a is in contact with the edge portion of the mounting hole 13b in the outer surface of the side wall portion 13. 82 a is welded to the outer surface of the side wall portion 13. At the time of laser irradiation, the laser is irradiated along the outer edge of the substantially inverted keyhole type attachment hole 13b. Thereby, compared with the case where a laser is irradiated in a simple circle shape, it becomes possible to raise welding strength. Further, when the laser is irradiated as described above, it is possible to perform welding at a position away from the reclining shaft 81 as compared with the case where the laser is irradiated in a simple circular shape. Further, by irradiating the laser as described above, welding is performed up to the upper end portion of the base portion 82a. As a result, the welding strength at the upper end of the base portion 82 a provided with the overhang portion 82 b is increased, and the support state of the overhang portion 82 b that receives the biasing force from the spiral spring 85 can be stabilized.

  A reclining device 80 (strictly speaking, a casing of the reclining device 80) is welded to the surface of the base portion 82 a that is located on the opposite side of the side wall portion 13. Further, the spiral spring 85 is disposed outside the reclining device 80 in the width direction. Furthermore, in the present embodiment, the second bracket 83 and the third bracket 84 are interposed between the reclining device 80 and the spiral spring 85 in the width direction.

  The second bracket 83 is joined (welded) to the reclining device 80 on the side opposite to the first bracket 82. As shown in FIG. 13, the second bracket 83 is formed with a circular hole 83a. A portion of the reclining shaft 81 that protrudes outward in the width direction from the casing of the reclining device 80 is inserted into the through-hole 83a.

  As shown in FIG. 13, the third bracket 84 includes a ring-shaped base portion 84 a and a protruding portion 84 b that protrudes outward in the width direction from the upper end portion of the base portion 84 a. The base portion 84a is welded to the outer surface of the second bracket 83 (the surface opposite to the side on which the reclining device 80 is welded). More specifically, a laser for welding is irradiated from the outer side in the width direction than the second bracket 83 in a state where the base portion 84a is in contact with the edge portion of the through hole 83a on the outer surface of the second bracket 83. By doing so, the base portion 84 a is welded to the outer surface of the second bracket 83. The other end portion of the spiral spring 85 is locked to the projecting portion 82b. One end of the spiral spring 85 is locked to the protruding portion 82b of the first bracket 82, and the other end is locked to the protruding portion 84b of the third bracket 84, so that the seat back S1 is moved forward. Is energized.

  With the configuration described above, in this embodiment, the reclining device 80 is appropriately attached to the side frame 10 made of a relatively thin steel material.

10 Side frame 10a Closed cross-section structure 10b Open cross-section structure 10s, 10t End 10v, 10w Overlapping part (two parts)
10u Escape part 10x Adjacent area 10y Separation area 11 Outer part 12 Inner part 13 Side wall part 13a Flange part 13b Mounting hole 13x Engagement hole 13y, 13z Insertion hole 14 Rear wall part 14a Flange part 14b Rear wall bead 15 Parts upper part 16 parts Center part 17 Parts lower part 20 First recess (recess)
21 Second recess (recess)
22 Convex bead 23 Weak part 30 Upper frame (connection frame)
31 Horizontal part (first extension part)
31a Bump 32 Lower extension (second extension)
32a Lower end portion 32b Skew portion 33 Connecting plate 34 Pillar guide 50 Lower member frame 60 S spring (support member)
70 Force cloth attachment clip (force cloth attachment member)
80 reclining device 81 reclining shaft 82 first bracket 82a base 82b overhang 83 second bracket 83a through hole 84 third bracket 84a base 84b overhang 85 spiral spring C closed space F1 seat back frame F2 seat cushion frame Q gap RL Lower rail RU Upper rail S This seat (vehicle seat)
S1 Seat back S2 Seat cushion S3 Headrest P Pad material W Skin material XL Rotating link

Claims (12)

A seat back frame having side frames provided at both ends in the width direction of a vehicle seat,
The side frame is
A closed cross-section structure portion having one end portion in the extending direction of the side frame, and a cross section intersecting with the extending direction being a closed cross-sectional structure;
A portion that is continuous with the closed cross-section structure portion in the extending direction, and an open cross-section structure portion in which the cross-section is an open cross-section structure,
A gap formed by discontinuation of a continuous portion in the cross section of the open cross-section structure portion is located adjacent to the closed cross-section structure portion in the extending direction in the open cross-section structure portion. It is larger than the region in the separation region located at a position away from the closed cross-section structure portion in the extending direction ,
A baffle attachment member for attaching a buff of an airbag is attached to the side frame,
In the longitudinal direction of the vehicle seat, the seat back frame mounting position of said force the cloth mounting member, characterized in that it is a position between the recess provided in the side frame and the closed cross section. The seat back frame according to claim 1, wherein the baffle attachment member is attached to the side frame at a plurality of positions sandwiching the concave portion. 3. The seat back frame according to claim 1, wherein the baffle attachment member is attached to the side frame at a plurality of positions sandwiching the recess in the extending direction of the side frame. The seat back frame according to any one of claims 1 to 3, wherein the baffle attaching member is attached to the side frame at a position surrounded by the recess. A support member installed between the side frames in the width direction to support an occupant is attached to the side frame,
The side frame is provided at a position behind the mounting position of the baffle mounting member in the front-rear direction of the vehicle seat and between the closed cross-sectional structure and the recess in the extending direction of the side frame. The seat back frame according to any one of claims 1 to 4, wherein an engagement hole for hooking the end portion is provided. The baffle attachment member is attached to the side frame by being inserted into a plurality of insertion holes provided in the side frame,
The seat back frame according to any one of claims 1 to 5, wherein a second hole is provided between the plurality of insertion holes in a vertical direction of the vehicle seat. The seat back frame according to claim 6, wherein the second hole is provided in the recess. The seat back frame according to claim 6, which is dependent on claim 5, wherein the second hole has a diameter larger than that of the engagement hole. The seat back frame according to claim 6, wherein the concave portion is provided above and below the second hole in the vertical direction of the vehicle seat. A seat cushion attached to the upper rail that is slidable along the lower rail fixed to the vehicle floor;
A seat back coupled to the seat cushion via a reclining device;
A vehicle seat including a headrest supported by an upper end portion of the seat back,
The seat back is
Side frames provided at both ends in the width direction of the vehicle seat;
A connecting frame that connects between the side frames,
The side frame is
A closed cross-section structure portion having one end portion in the extending direction of the side frame, and a cross section intersecting with the extending direction being a closed cross-sectional structure;
A portion that is continuous with the closed cross-section structure portion in the extending direction, and an open cross-section structure portion in which the cross-section is an open cross-section structure,
A gap formed by discontinuation of a continuous portion in the cross section of the open cross-section structure portion is located adjacent to the closed cross-section structure portion in the extending direction in the open cross-section structure portion. It is larger than the region in the separation region located at a position away from the closed cross-section structure portion in the extending direction,
A baffle attachment member for attaching a buff of an airbag is attached to the side frame,
A vehicular seat characterized in that, in the front-rear direction of the vehicular seat, the attachment position of the baffle attachment member is a position between the closed cross-sectional structure and the recess provided in the side frame. A seat back frame having side frames provided at both ends in the width direction of a vehicle seat,
The side frame is
A closed cross-section structure portion having one end portion in the extending direction of the side frame, and a cross section intersecting with the extending direction being a closed cross-sectional structure;
A portion that is continuous with the closed cross-section structure portion in the extending direction, and an open cross-section structure portion in which the cross-section is an open cross-section structure,
A baffle attachment member for attaching a buff of an airbag is attached to the side frame,
The seat back frame according to claim 1, wherein a mounting position of the baffle mounting member is a position between the closed cross-sectional structure and a recess provided in the side frame in the front-rear direction of the vehicle seat. A seat cushion attached to the upper rail that is slidable along the lower rail fixed to the vehicle floor;
A seat back coupled to the seat cushion via a reclining device;
A vehicle seat including a headrest supported by an upper end portion of the seat back,
The seat back is
Side frames provided at both ends in the width direction of the vehicle seat;
A connecting frame that connects between the side frames,
The side frame is
A closed cross-section structure portion having one end portion in the extending direction of the side frame, and a cross section intersecting with the extending direction being a closed cross-sectional structure;
A portion that is continuous with the closed cross-section structure portion in the extending direction, and an open cross-section structure portion in which the cross-section is an open cross-section structure,
A baffle attachment member for attaching a buff of an airbag is attached to the side frame,
A vehicular seat characterized in that, in the front-rear direction of the vehicular seat, the attachment position of the baffle attachment member is a position between the closed cross-sectional structure and the recess provided in the side frame.

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