JPWO2016021554A1 - Seat frame - Google Patents

Abstract

Provided is a seat frame in which weight reduction is realized while ensuring rigidity of the seat frame. The seat back frame (1) includes left and right side frames (2) having an I-shaped cross section extending in the vertical direction, and an upper frame (3) connecting the ends of the left and right side frames (2). Forms the skeleton of the sheet. The side frame (2) includes a rear end (21) and a front end (23) at both ends in the front-rear direction orthogonal to the vertical direction and the seat width direction, and the rear end (21) and the front end (23). Intermediate portion (22) between the rear end portion (21) and the front end portion (23) in the sheet width direction is greater than the length in the sheet width direction of the intermediate portion (22), In the intermediate part (22), a hollow hole (22d) drilled in the sheet width direction and a bracing (22e, 22f) crossing the thin hole (22d) are formed.

Description

  The present invention relates to a seat frame, and more particularly, to a seat frame considering weight reduction and securing of rigidity.

A member provided in a vehicle needs to secure rigidity while reducing the weight for the purpose of improving fuel consumption.
In view of this, it is known to form a seat frame forming a skeleton of a vehicle seat from a resin instead of a metal (for example, Patent Document 1).
In particular, FIG. 13 of Patent Document 1 describes a side frame formed in an I-shaped cross section that constitutes a seat frame.
In addition, there is a seat back frame that is a framework of a backrest portion of a vehicle seat, which has a configuration in which yoke members are welded to left and right side frames. The load resistance of the side frame (side beam) may be reduced by a load applied to the yoke member from a seated person. In Patent Document 2, in order to avoid this reduction in load resistance, a spacer member serving as a yoke member coupled to a thin metal plate is provided between the left and right side frames constituting the seat back frame, and this thin metal plate is provided. A technique for fixing a side frame is disclosed.

JP 2013-227007 A JP 59-57034 A

However, the vehicle seat disclosed in Patent Document 1 is not sufficient in terms of weight reduction for improving fuel efficiency, and it is difficult to ensure rigidity when the weight is reduced.
Moreover, according to the invention described in Patent Document 2, by attaching the spacer member to the side frame via the thin metal plate, it is possible to prevent a torsional load from being applied to the side frame due to a load from the back of the occupant. However, there was no change in reducing the load resistance of the side frame by applying a bending load.
Further, simply increasing the rigidity of the spacer member may hinder weight reduction.
The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a seat frame in which weight reduction is realized while securing the rigidity of the seat frame.
Another object of the present invention is to provide a lightweight seat frame that can efficiently suppress twisting and bending.

  According to the seat frame of the present invention, the subject is a seat frame having left and right side frames having an I-shaped cross section extending in the longitudinal direction to form a skeleton of the seat, wherein the side frame is And both ends of the transverse direction orthogonal to the direction and the sheet width direction, and an intermediate portion between the both ends, the length of the both ends in the sheet width direction is the intermediate This is solved by the fact that the intermediate portion is formed with a cutout hole that is perforated in the sheet width direction and a brace that crosses the cutout hole. .

  As in the above configuration, the sectional shape of the side frame is I-shaped, so that the sectional moment and the sectional secondary pole moment of the side frame can be increased, and the bending rigidity and torsional rigidity can be increased. . Furthermore, the balance of rigidity can be increased by the symmetry of the cross-sectional shape, and the rigidity is ensured by bracing while reducing the weight by forming a hollow hole in the middle part of the side frame. be able to. The I-shaped cross section according to the present invention means that both end portions have a larger cross sectional shape in the sheet width direction than the intermediate portion.

Furthermore, it is preferable that the dimension in the sheet width direction at either end of the both ends is larger than the dimension in the lateral direction at the end.
According to the above configuration, since the dimension in the sheet width direction at either end of the both ends is larger than the dimension in the short direction at the end, the bending rigidity and torsional rigidity of the side frame in the sheet width direction are increased. , It can be efficiently secured for a predetermined volume.

Moreover, it is preferable that the dimension in the lateral direction at either end of the both end parts is larger than the dimension in the sheet width direction at the intermediate part.
According to the said structure, the bending rigidity and torsional rigidity of a side frame are securable, suppressing the dimension of the sheet width direction in the intermediate part of a side frame.

Moreover, the cross section of the said both ends in the said side frame may be circular or an ellipse shape.
According to the said structure, since the cross section of both ends is a circle or an ellipse shape and there is no edge, damage to the urethane pad which touches both ends can be suppressed.

Further, the seat frame is a seat back frame, the side frame extends in the vertical direction as the longitudinal direction, the lateral direction is the front-rear direction, and the both end portions are the front side portion and the rear side. It may consist of parts.
According to the said structure, the bending rigidity and torsional rigidity of the side frame of a seat back frame can be improved, and the balance of rigidity can be made high by the symmetry of the cross-sectional shape.

The side frame has substantially the same size in the front-rear direction of the upper part and the lower part, and the front-rear dimension of the front side part or the rear side part of the upper part is the front side part or the rear side part of the lower part. Is preferably smaller than the dimension in the front-rear direction.
According to the above configuration, by reducing the longitudinal dimension of the front side part or the rear side part in the upper part relative to the longitudinal dimension of the front side part or the rear side part in the lower part where the load is close to the waist of the seated person, Rigidity can be efficiently secured while considering weight reduction.

The length of the side frame in the front-rear direction is shorter in the upper part than in the lower part, and the front-rear part or the rear side part in the upper part of the side frame has a front-rear width in the lower part of the side frame. It is preferable that the width is larger than the width in the front-rear direction of the front side part or the rear side part.
According to the above configuration, it is necessary to secure the rigidity of the front side portion or the rear side portion in the upper portion while shortening the length in the front-rear direction in the upper portion of the side frame that is not an effective part for supporting the seated person. Therefore, by increasing the width in the front-rear direction, it is possible to efficiently reduce the weight while ensuring the rigidity of the seat back frame.

Further, it is preferable that the side frame is quenched only in the upper part formed in a short length in the front-rear direction.
According to the said structure, intensity | strength can be improved by hardening process, suppressing the length of the front-back direction in the upper part of a side frame.

It is preferable that a plurality of the braces are formed, and at least two of the braces extend so as to be separated from each other toward the rear of the seat.
According to the said structure, the support force with respect to the load added to a side frame can be improved widely, and rigidity can be ensured efficiently.

  The seat frame is a seat back frame that forms a skeleton of a backrest portion, and includes a connection frame that includes a front plate and a rear plate and connects the left and right side frames, and the front plate and the rear side. At least one of the plates is formed with another hollow hole penetrating in the front-rear direction and an erected portion that extends over the other hollow hole, and the front plate and the rear plate Is solved by joining at the lower edge of the connecting frame.

  As in the above configuration, at least one of the front plate and the rear plate is formed with another hollow hole penetrating in the front-rear direction, and an erected portion is formed over the other hollow hole. This makes it possible to reduce the weight and to efficiently suppress twisting and bending, and to join the connecting frame from the back of the seated person by joining the front plate and the rear plate at the lower edge of the connecting frame. A seat frame having high rigidity against a load can be provided.

Further, it is preferable that the front plate and the rear plate are joined in the vicinity of the end portion of the erection portion in the lower edge of the connection frame.
According to the above configuration, the front plate and the rear plate are joined in the vicinity of the end portion of the erection portion, so that the rigidity of the connection portion between the front plate and the rear plate where stress is easily concentrated is increased. Can be ensured by.

Further, it is preferable that the erection portion extends to a corner portion of the connection frame.
According to the above configuration, since the erection portion extends at the corner of the connecting frame, a reaction force is generated from the corner when an external force is applied to the erection, thereby suppressing bending of the erection portion. Can do.

In addition, it is preferable that the erection portion extends toward a connection portion between the connection frame and the left and right side frames.
According to the above configuration, since the extension extends toward the connection portion between the left and right side frames in the connection frame, the installation portion ensures the rigidity of the connection portion between the connection frame and the side frame where stress is likely to concentrate. Can do.

Further, one side edge portion of the front plate or the rear plate extends toward the other side so as to be bent, and is joined to the other side, and the left and right side frames and the connection frame are connected to each other. It is preferable that the portion to be formed forms a closed cross-sectional shape by being surrounded by the front plate, the rear plate, and the side edge portion.
According to the above configuration, the connection frame and the left and right side frames form a closed cross-sectional shape at a portion where the connection frame and the left and right side frames are connected, so that the rigidity of the portion can be increased.

Further, a guide holder for supporting a part of the headrest frame is attached to the connection frame, and the guide holder is disposed between the front plate and the rear plate, A part of the part is preferably arranged so as to overlap the guide holder in the front-rear direction.
According to the above configuration, the connection frame is provided with the guide holder for supporting a part of the headrest frame between the front plate and the rear plate, and a part of the erection part is disposed in the front and rear direction with the guide holder. By being formed so as to overlap, the rigidity of the guide holder that supports a part of the headrest frame can be efficiently ensured by the installation portion.

According to the present invention, the cross-sectional secondary moment and the cross-sectional secondary pole moment of the side frame can be increased, and the bending rigidity and torsional rigidity can be increased. Furthermore, the balance of rigidity can be increased by the symmetry of the cross-sectional shape, and the rigidity is ensured by bracing while reducing the weight by forming a hollow hole in the middle part of the side frame. be able to.
Further, according to the present invention, since the dimension in the sheet width direction at either end of the both ends is larger than the dimension in the lateral direction at the end, the bending rigidity and torsion of the side frame in the sheet width direction are increased. Rigidity can be efficiently secured for a predetermined volume.
Further, according to the present invention, it is possible to ensure the bending rigidity and torsional rigidity of the side frame while suppressing the dimension in the seat width direction at the intermediate portion of the side frame.
Moreover, since the cross section of both ends is a circle or an ellipse and there is no edge, the damage of the urethane pad which touches both ends can be suppressed.
Moreover, the bending rigidity and torsional rigidity of the side frame of the seat back frame can be increased, and the balance of rigidity can be increased by the symmetry of the cross-sectional shape.
In addition, the front / rear dimension of the front side or rear side at the upper part is smaller than the front / rear dimension of the front side or rear side at the lower part where the load is close to the waist of the seated person. However, the rigidity can be efficiently secured.
In addition, it is necessary to ensure the rigidity of the front side part or the rear side part of the upper part of the side frame while shortening the length in the front-rear direction at the upper part of the side frame, which is not an effective part for supporting the seated person. By increasing the direction width, it is possible to reduce the weight efficiently while securing the rigidity of the seat back frame.
Furthermore, the strength can be improved by quenching while suppressing the length in the front-rear direction at the upper part of the side frame.
Moreover, the supporting force with respect to the load applied to the side frame can be increased widely, and the rigidity can be efficiently secured.
In addition, according to the present invention, the weight can be reduced, and twisting and bending can be efficiently suppressed, and the front plate and the rear plate are joined at the lower edge of the connection frame, so that the connection frame can be connected from the back. A seat frame having high rigidity against a load applied to the lower edge side can be provided.
Furthermore, according to this invention, the rigidity of the connection part of the front side plate and the rear side plate where stress tends to concentrate can be ensured by the installation part.
Moreover, according to this invention, when external force is added to a construction part, the reaction force from a corner | angular part arises, and it can suppress the bending of a construction part.
Moreover, according to this invention, the rigidity of the connection part of a connection frame and a side frame where stress tends to concentrate can be ensured by the installation part.
Moreover, according to this invention, the rigidity of the part to which a connection frame and the left and right side frames are connected can be improved.
Further, according to the present invention, the rigidity of the guide holder that supports a part of the headrest frame can be efficiently ensured by the installation portion.

It is a perspective view showing a seat back frame concerning a 1st embodiment. It is sectional drawing of a side frame, and is a figure which shows the IIA-IIA cross section of FIG. It is sectional drawing of a side frame, and is a figure which shows the IIB-IIB cross section of FIG. It is a perspective view which shows the seat back frame which concerns on 2nd Embodiment. It is sectional drawing of the side frame which concerns on 2nd Embodiment, and is a figure which shows the IVA-IVA cross section of FIG. It is sectional drawing of the side frame which concerns on 2nd Embodiment, and is a figure which shows the IVB-IVB cross section of FIG. In the side frame which concerns on a modification, it is a figure which shows the example in which the front-back width of the rear side part was formed larger than the front-back width of a front side part. It is a figure which shows the example which performed the quenching process to the side frame which concerns on a modification, and is a figure which shows the example which performed the quenching process to the whole rear side part and the whole front side part. It is a figure which shows the example which performed the hardening process to the side frame which concerns on a modification, and is a figure which shows the example which applied the hardening process to the rear side of the rear side part, and the whole front side part. It is a figure which shows the example which performed the quenching process to the side frame which concerns on a modification, and is a figure which shows the example which performed the quenching process to the left-right side of the rear side part, and the left-right side of the front side part. It is a figure which shows the example which comprises the side frame which concerns on the modified example comprised by welding two frame pieces of U-shaped cross section back to back. It is sectional drawing of the side frame which concerns on a modification. It is sectional drawing of the side frame which has the hollow part which concerns on a modification. It is sectional drawing of the side frame in which the rear side part was formed larger than the front side part. It is sectional drawing of the side frame which concerns on the modified example comprised by welding two flame | frame pieces back to back. It is a whole perspective view which shows the seat back frame which concerns on 3rd Embodiment. It is a rear view of a seat back frame. It is a perspective view which shows the junction part of a rear side plate and a front side plate, and the junction part of an upper frame and a side frame. It is a schematic diagram which shows an example of the junction part of a rear side plate and a front side plate. It is a schematic diagram which shows an example of the junction part of a rear side plate and a front side plate. It is a schematic diagram which shows an example of the junction part of a rear side plate and a front side plate.

  A seat back frame 1, 1a according to an embodiment of a seat frame of the present invention will be described with reference to the drawings.

<< First Embodiment >>
First, the overall configuration of the seatback frame 1 and the overall schematic configuration of the side frame 2 will be described with reference to FIGS. 1 and 2. Here, FIG. 1 is a perspective view showing the seat back frame 1 according to the first embodiment, FIG. 2 is a cross-sectional view of the side frame 2, and FIG. 2A is a cross-sectional view taken along the line IIA-IIA in FIG. 2B is a view showing a IIB-IIB cross section of FIG.

  The seat back frame 1 corresponds to a seat frame according to the present invention. The seat back frame 1 is arranged on the left and right and extends vertically, and continuously formed below the left and right side frames 2 and extends in the seat width direction. A lower frame 4 and an upper frame 3 as a connecting frame according to the present invention for supporting the back of the seated person by connecting the upper parts of the left and right side frames 2. Hereinafter, the sheet width direction is also referred to as the left-right direction.

  The side frame 2 includes a rear side portion 21 at the rear edge, a front side portion 23 at the front edge, and an intermediate portion 22 that connects the rear side portion 21 and the front side portion 23, each extending vertically. The horizontal cross section forms an I-shape.

The rear side portion 21 and the front side portion 23 are formed with substantially equal lengths in the sheet width direction.
The intermediate portion 22 extends substantially perpendicularly at each approximate center in the sheet width direction. In particular, each of the intermediate portions 22 of the left and right side frames 2 is formed with a through hole 22d penetrating in the intermediate portion in the vertical direction in the seat width direction. Weight reduction is achieved by this hole 22d. The vertical direction corresponds to the longitudinal direction according to the present invention.

In the hollow hole 22d, braces 22e and 22f are formed so as to cross in the front-rear direction corresponding to the short direction according to the present invention. By forming the braces 22e and 22f, it is possible to compensate for the decrease in rigidity due to the hollow holes 22d.
In particular, the side frame 2 formed with an I-shaped horizontal cross section is formed with the lightening holes 22d and the braces 22e and 22f, so that the weight can be reduced and the rigidity can be secured in a balanced manner. It becomes possible.
Furthermore, the braces 22e and 22f extend so as to be spaced apart from the front toward the rear. By being formed in this way, it is possible to broaden the support force against the load from the front side applied to the side frame 2 and to ensure the rigidity efficiently. The number of the braces 22e and 22f may be one or more, and is arbitrary.

  Further, at least one intermediate portion 22 of the side frame 2 is formed with an attachment hole 22g for fixing an unillustrated airbag, reclining unit, actuator, occupant detection unit, or the like. If the attachment hole 22g is formed at a position avoiding the extension of the braces 22e and 22f, it is preferable not to inhibit the rigidity improvement by the braces 22e and 22f.

As shown in FIG. 1, the length of the upper part 2a in the side frame 2 in the front-rear direction is shorter than the length in the front-rear direction of the lower part 2b. By being formed in this way, a space in the vicinity of the chest and arms of the seated person is secured, and the degree of freedom is avoided from being limited.
As shown in FIG. 2A for the horizontal cross section of the upper portion 2a and in FIG. 2B for the horizontal cross section of the lower portion 2b, the longitudinal width da of the rear side portion 21a and the front side portion 23a of the upper portion 2a is the rear side portion 21b and front side portion 23b of the lower portion 2b. Is larger than the front-rear width db.
Thus, since the front-rear width da of the rear side part 21a and the front side part 23a is formed large, even if the length in the front-rear direction of the upper part 2a of the side frame 2 is formed short, the section modulus is increased. Can be secured.

  In addition, fillets 24 are formed at the connection portion between the rear side portion 21a and the front side portion 23a and the intermediate portion 22a of the upper portion 2a and at the connection portion between the rear side portion 21b and the front side portion 23b and the intermediate portion 22b of the lower portion 2b. ing. This fillet 24 is a portion that is generated when the side frame 2 is forged, and it is possible to reinforce a corner portion where stress concentration occurs. When the probability of deformation due to stress concentration is low, the fillet 24 is not always necessary.

<< Second Embodiment >>
Next, the seat back frame 1a according to the second embodiment will be described with reference to FIGS. Here, FIG. 3 is a perspective view showing the seat back frame 1a according to the second embodiment, FIG. 4 is a cross-sectional view of the side frame according to the second embodiment, and FIG. FIG. 4B is a diagram showing a cross section of IVA-IVA, and FIG. 4B is a diagram showing a cross section of IVB-IVB in FIG.
The seat back frame 1a according to the second embodiment is different from the seat back frame 1 according to the first embodiment shown and described in FIG. 1, and as shown in FIG. Is substantially equal to the length of the lower portion 7b in the front-rear direction.

Each of the side frames 7 includes a rear side portion 71 at the rear edge, a front side portion 73 at the front edge, and an intermediate portion 72 that connects the rear side portion 71 and the front side portion 73, extending vertically. The horizontal cross section forms an I-shape.
As shown in FIG. 4A for the horizontal cross section of the upper part 7a and in FIG. 4B for the horizontal cross section of the lower part 7b, the front and rear widths dd of the rear side part 71b and the front side part 73b of the lower part 7b are the rear side part 71a and front side part 73a. Is larger than the front-rear width dc.
By forming in this way, in the side frame 7, since the section modulus of the lower part 7b is larger than that of the upper part 7a and the rigidity is increased, the waist of the seated person adjacent to the lower part 7b is suitably supported. It becomes possible.
As in the first embodiment, the rear portion 71a and the front portion 73a of the side frame 7 are connected to the intermediate portion 72a and the rear portion 71b and the front portion 73b and the intermediate portion of the lower portion 7b. A fillet 74 is also formed at the connection portion with 72b.

(First modification)
Next, the rear side part 71c and the front side part 73c in the lower part 7c of the side frame 7 which concerns on a 1st modification are demonstrated with reference to FIG. Here, FIG. 5 is a diagram illustrating an example in which the front-rear width dd of the rear side 71c is formed larger than the front-rear width de of the front side 73c in the side frame 7 according to the modification.
The front-rear width dd of the rear side portion 71c of the side frame 7 is formed larger than the front-rear width de of the front side portion 73c. When formed in this way, it is preferable in terms of securing rigidity while reducing the weight. This is because the rear side portion 71c is connected to the lower frame 4, and a bending moment is generated when an external force is applied, so that rigidity higher than that of the front side portion 73c is required.

Further, the front and rear widths dd and de of at least one of the rear side 71c or the front side 73c of the upper part 7a or the lower part 7b of the side frame 7 are formed to be larger than the lateral width f of the intermediate part 72c. By being formed in this way, the size of the side frame 7 in the seat width direction can be suppressed to be suitable for attachment of an airbag or the like, and the rigidity can be improved by increasing the section modulus.
In this way, the front-rear width dd of the rear side portion 71c is made larger than the front-rear width de of the front side portion 73c, and the front-rear widths dd, de of the rear side portion 71c or the front side portion 73c are made equal to the lateral width f of the intermediate portion 72c. The formation larger than the dimension is not limited to the side frame 7 according to the second embodiment, but may be applied to the side frame 2 according to the first embodiment. Furthermore, the present invention may be applied to any of the upper portions 2a and 7a and the lower portions 2b and 7b. The same applies to the modifications described below.

(Second modification)
Next, side frames 70, 70a, and 70b according to a second modification will be described with reference to FIG. Here, FIG. 6 is a diagram illustrating an example in which the side frames 70, 70a, and 70b according to the second modified example are subjected to quenching, and FIG. 6A illustrates the entire rear side portion 71d and the entire front side portion 73d. The figure which shows the example which performed the quenching process, FIG. 6B is the figure which shows the example which performed the quenching process to the whole rear side 71d of the rear side part 71e, FIG. 6C is the right and left sides of the rear side part 71f, and It is a figure which shows the example which performed the hardening process to the left-right side of the front side part 73e.

As shown in FIG. 6A, the side frame 70 has the entire rear side portion 71d and the entire front side portion 73d quenched.
In addition, as shown in FIG. 6B, the side frame 70a is quenched on the entire rear side and front side portion 73d of the rear side portion 71e.
Furthermore, as shown in FIG. 6C, the side frame 70b is quenched q on the left and right sides of the rear side portion 71f and the left and right sides of the front side portion 73e.

By performing quenching q like the side frames 70, 70a, and 70b, it is possible to improve the strength while suppressing an increase in weight. In addition, the partial quenching as shown in FIG. 6B and FIG. 6C is such that an induction coil (not shown) is disposed only in a portion where quenching q is performed, or a workpiece is moved in the induction coil so that quenching q is performed. This is done by shortening the time.
In particular, the rear side portion 71e shown in FIG. 6B has a shorter quenching time than the rear side portion 71d shown in FIG.
Further, the quenching q may be applied to the other side frame 2, and in particular, if it is applied to the upper part 2a of the side frame 2 having a short length in the front-rear direction and low rigidity, the strength is improved and the rigidity is increased. Is preferred.

(Third Modification)
Next, a side frame 70c according to a third modification will be described with reference to FIG.
The side frame 70c is a frame that is U-shaped in cross section and is joined so that two frame pieces 70d and 70e made of sheet metal are back-to-back and extend vertically. In each of the frame pieces 70d and 70e constituting the side frame 70c, the rear side plate 75g and the rear side plate 75h, and the front side plate 77g and the front side plate 77h are arranged on the same plane. The frame pieces 70d and 70e are welded by the spot welded portion 78 in a state where the intermediate plate 76g and the intermediate plate 76h are face to face.
That is, by welding in this way, the rear side plate 75g and the rear side plate 75h constitute the rear side portion 75, the intermediate plate 76g and the intermediate plate 76h constitute the intermediate portion 76, and the front side plate 77g and the front side plate 75g. The front side 77 is constituted by the side plate 77h.

In particular, if the frame pieces 70d and 70e are formed in a symmetrical common shape, parts management is enhanced, assembly work is facilitated, and moreover, a plurality of types of molds are not required, thereby reducing mold costs. Can do.
As described above, the side frame according to the present invention may be the side frames 2 and 7 in which the portion having the I-shaped cross section is integrally formed, but is welded by spot welding or other resistance welding. The side frame 70c may be used.

(Fourth modification)
Next, a side frame 8 according to a fourth modification will be described with reference to FIG.
The side frame 8 is a plate-like shape in which the horizontal cross section is circular or elliptical, and the rear side portion 81a and the front side portion 83a are connected to the rear side portion 81a and the front side portion 83a so that the thickness direction is the left-right direction. Intermediate portion 82a.
Thus, the horizontal cross section of the rear side part 81a and the front side part 83a is formed in circular shape or elliptical shape, and the edge is not formed. For this reason, it can suppress that the cushion pad which is not shown in contact with the rear side part 81a and the front side part 83a deteriorates by the friction with the rear side part 81a and the front side part 83a.

(Fifth modification)
Side frames 80 and 80a according to a fifth modification will be described with reference to FIG. Here, FIG. 9A is a cross-sectional view of the side frame 80 having the hollow portions 84a and 84b according to the fifth modification, and FIG. 9B is a side frame 80a in which the rear side portion 81c is formed larger than the front side portion 83b. It is sectional drawing.
The side frames 80 and 80a include hollow portions 84a and 84c having a circular cross section at the rear side portions 81b and 81c, and a hollow portion 84b having a circular cross section at the front side portion 83b.
The side frames 80 and 80a are lighter than the side frame 8 according to the fourth modification because the hollow portions 84a, 84b, and 84c are formed.

The side frame 80a is formed such that the rear side portion 81c is larger than the front side portion 83b, so that the rear cross-sectional area where the compressive stress is large can be increased and the rigidity can be increased.
Note that the I-shaped cross section according to the present invention means that both end portions have a larger cross sectional shape than the intermediate portion, and in addition to the side frame 2 according to the first embodiment, The cross section includes a circular rear side portion 81a and a front side portion 83a.

(Sixth Modification)
Next, a side frame 9 according to a sixth modification will be described with reference to FIG.
The side frame 9 is a frame in which two frame pieces 90a and 90b, which are sheet metals, are joined so as to be back to back and extend vertically.

Specifically, the frame piece 90a is formed at an intermediate plate 92a extending linearly in the front-rear direction in a horizontal section, a front plate 93a having an arcuate cross section formed at the front end of the intermediate plate 92a, and a rear end of the intermediate plate 92a. And a rear plate 91a having a circular arc cross section and extending in the vertical direction.
Similarly, the frame piece 90b is formed at the intermediate plate 92b extending linearly in the front-rear direction in the horizontal cross section, the front plate 93b having an arcuate cross section formed at the front end of the intermediate plate 92b, and the rear end of the intermediate plate 92b. And a rear plate 91b having an arcuate cross section and extending in the vertical direction.
The frame pieces 90a and 90b constituting the side frame 9 are respectively arranged on the same true circle or ellipse circumference in the horizontal cross section in the rear side plate 91a and the rear side plate 91b, and the front side plate 93a and the front side plate 93b. It is formed so that. And the frame pieces 90a and 90b are welded by the spot welding part 94 in the state in which the intermediate plate 92a and the intermediate plate 92b are face-to-face.

  In particular, gaps c are formed between the front end of the front plate 93a and the front end of the front plate 93b, and between the rear end of the rear plate 91a and the rear end of the rear plate 91b. Since the gap c is formed in this way, it is possible to avoid interference between both ends due to a dimensional error when combining before spot welding, and abnormal noise caused by contact with a load from a seated person can be avoided. Occurrence can be prevented. In addition, you may make it weld a part or all range of both ends by welding, without forming the clearance gap c.

  In the said embodiment, the side frame of the seat back was made into I shape, and it demonstrated as what forms a cut-out hole and forms a bracing. However, such a configuration is not limited to the side frame of the seat back, and can be similarly applied to the side frame of the seat cushion.

<< Third Embodiment >>
A seat back frame 1 according to a third embodiment of the present invention will be described with reference to FIGS. 11 and 12. Here, FIG. 11 is an overall perspective view showing the seat back frame 1 according to the present embodiment, and FIG. 12 is a rear view of the seat back frame 1.

  The upper frame 3 constituting the seat back frame 1 corresponds to a connecting frame according to the present invention, and a substantially trapezoidal rear plate 30 and a front plate 31 having substantially the same outer shape as the rear plate 30 are arranged in the front-rear direction. It is configured to be overlapped at intervals. Specifically, the upper frame 3 is overlapped in the front-rear direction by forming a hollow inside the rear plate 30 and the front plate 31 by a side edge portion 31k described later and a joint portion 31f described later. The left and right side frames 2 are welded to the upper frame 3 while being inserted into the left and right ends of the upper frame 3 from below and sandwiched in the front-rear direction.

  As shown in FIG. 12, the rear plate 30 is formed with a triangular hole 30a on the lower center side and an inverted triangular hole 30b on the upper center side. Thus, the weight reduction of the rear side plate 30 is achieved by forming the lightening holes 30a and 30b as other lightening holes.

As shown in FIG. 11, the front plate 31 has a triangular hollow hole 31 a formed at the center lower side, and an inverted triangular hollow hole 31 b formed at the upper center side. Both of the lightening holes 31a and 31b are formed at positions where they overlap the front and rear of the lightening holes 30a and 30b of the rear plate 30.
Further, the front side plate 31 has other thinning holes 31a, 31b, 31c, 31d as other thinning holes having a substantially triangular shape divided by a brace 31e formed in an X shape continuously with the front side plate 31. Is formed. In other words, the bracing 31e corresponding to the erection part according to the present invention is erected beyond the lightening holes 31a, 31b, 31c, 31d.

  In particular, the brace 31e extends in an X shape toward the lower two corners 31h and the upper two corners 31i of the upper frame 3. By forming the braces 31e as described above, it is possible to suppress the braces 31e from being bent by reaction forces generated from the corner portions 31h and 31i when an external force is applied to the braces 31e. .

  Further, a peripheral edge (side edge) other than the lower edge of the front plate 31 is formed with a side edge portion 31k bent to the rear plate 30 side, and the side edge portion 31k and the rear plate 30 are welded. Yes.

Two notches 31j are formed on the upper portion of the front plate 31, and the guide holder 5 protrudes upward from the notches 31j.
The guide holder 5 is a member for inserting and supporting a part of a headrest frame (not shown) that forms the skeleton of the head of a vehicle seat (not shown), and is supported by the rear plate 30 and the front plate 31. They are joined together in a state of being sandwiched between them.
In particular, as shown in FIG. 11, when the guide holder 5 is disposed in a portion that overlaps the bracing 31e in the upper frame 3 and has a high rigidity, the joining of the guide holder 5 can be stabilized.
In the above description, the bracing 31e is formed on the front plate 31. However, the bracing and lightening holes may be formed on the rear plate 30 similarly to the front plate 31. Good.

Next, the joining of the rear plate 30 and the front plate 31 and the joining of the upper frame 3 and the side frame 2 will be described with reference to FIGS. 13 and 14A to 14C.
Here, FIG. 13 is a perspective view showing a joint portion between the rear plate 30 and the front plate 31 and a joint portion between the upper frame 3 and the side frame 2, and each of FIGS. 14A to 14C shows the rear plate 30. It is a schematic diagram which shows an example of the junction part of and the front side plate 31. FIG.

  At the lower end portion of the front plate 31, a joining portion 31f for joining to the rear plate 30 is formed. The joining portion 31 f is bent and extended backward at an angle of about 90 degrees from the front surface of the front plate 31 at the lower end portion of the front plate 31 and is welded to the rear plate 30. The front plate 31 and the rear plate 30 are joined by the joining portion 31f. Thus, since the joining portion 31f extends from the lower end of the front plate 31, a separate member for joining the rear plate 30 and the front plate 31 becomes unnecessary.

  In particular, as shown in FIG. 14A, the joint portion 31f is bent from the front plate 31 on the front side and welded to the rear plate 30 on the rear side. And the junction part 31f is not what was bent from the rear side plate 30 and welded to the front side plate 31 by the front side like the junction part 30g shown to FIG. 14B. For this reason, on the front side where a repeated load from the seated person is applied, the cushion pad (not shown) is prevented from coming into contact with the welded portion, and the smooth bent portion is brought into contact with the cushion pad. Can be prevented.

  Further, as shown in FIG. 14C, the joint 31g extends from the front plate 31, and the joint 30h extends from the rear plate 30 to a position facing the joint 31g, so that the joint 31g and the joint 30h are extended. May be welded together. That is, if the joint part 31g and the joint part 30h are welded to the position where the joint part 31f shown in FIG. 14A is formed, the edge of the welded part does not occur on both the front side and the rear side. Damage can be prevented more.

  In particular, as shown in FIG. 11, the joint portion 31f is formed near the corner portion 31h at the lower end of the brace 31e. For this reason, the rigidity in the vicinity of the joint portion 31f where stress is easily concentrated due to the joint portion can be increased by the brace 31e, and the torsional rigidity of the upper frame 3 can be increased.

  Further, as shown in FIG. 13, the I-shaped left and right side frames 2 are inserted between the rear plate 30, the front plate 31, and the side edge portion 31 k at the left and right ends of the upper frame 3. It is welded and combined with the upper frame 3 to form a closed cross-sectional shape. By being formed in this way, the rigidity of the connecting portion between the side frame 2 and the upper frame 3 is enhanced. Furthermore, since the bracing 31e extends to this connecting portion, the bracing 31e can ensure the rigidity of the connecting portion between the rear plate 30 and the front plate 31 where stress is easily concentrated.

The above embodiment 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 spirit of the present invention, and of course, the present invention includes equivalents thereof.
In particular, it is arbitrary to combine or delete the features described in each embodiment or the features described in each modification.

  The bracing as the erection part according to the present invention has been described as having an X shape in front view, but the present invention is not limited to this shape. For example, the erection part has the shape of “X” and “I” stacked (* shape), the shape of “X” and “+” stacked (US shape), and the shape of “X” and “-” stacked. In addition, it is possible to adopt an arbitrary shape such as a C-shape, and it is constructed over the hollow hole so as to connect at least two arbitrary portions of the upper and lower and left and right portions of the upper frame. That's fine.

1,1a Seat back frame (seat frame)
2, 7, 70, 70a, 70b, 8, 80, 80a, 9 Side frame 2a, 7a Upper part 2b, 7b, 7c Lower part 21, 21, a, 21b Rear side part 22, 22a, 22b Middle part 22d Meat hole 22e, 22f Bracing 22g Mounting hole 23, 23a, 23b Front side 24 Fillet 70d, 70e, 90a, 90b Side frame piece 71, 71a, 71b, 71c, 71d, 71e, 71f, 75 Rear side 72, 72a, 72b, 72b, 76 Intermediate portion 73, 73a, 73b, 73c, 73d, 73e, 77 Front side portion 74 Fillet 75g, 75h Rear side plate 76g, 76h Intermediate plate 77g, 77h Front side plate 78 Spot welded portion 81a, 81b, 81c Rear side portion 82a Intermediate part 83a, 83b Front side part 84a, 84b, 84c Hollow part 91 Rear side part 91a, 91b Rear Side plate 92 Intermediate portion 92a, 92b Intermediate plate 93 Front side portion 93a, 93b Front side plate 94 Spot welded portion 3 Upper frame (connection frame)
30 Rear plate 30a, 30b Mouth hole (other hole)
30d, 30f joint 30g, 30h joint 31 front plate 31a, 31b, 31c, 31d
31e Bracing (erection part)
31f, 31g Joint portion 31h, 31i Corner portion 31j Notch 31k Side edge portion 4 Lower frame 5 Guide holder c Clearance da, db, dc, dd, de Front-back width f Horizontal width q Quenching

Claims (15)

A seat frame comprising left and right side frames with an I-shaped cross section extending in the longitudinal direction to form a skeleton of the seat,
The side frame has both end portions at both ends in the short direction perpendicular to the longitudinal direction and the sheet width direction, and an intermediate portion between the both end portions,
The length of the both end portions in the sheet width direction is larger than the length of the intermediate portion in the sheet width direction,
The seat frame according to claim 1, wherein a cutout hole formed in the width direction of the sheet and a brace that crosses the cutout hole are formed in the intermediate portion.   2. The seat frame according to claim 1, wherein a dimension in the sheet width direction at either end of the both end parts is larger than a dimension in the lateral direction at the end.   2. The seat frame according to claim 1, wherein a dimension in the short-side direction at any one of the both end parts is larger than a dimension in the sheet width direction at the intermediate part.   The seat frame according to claim 1, wherein a cross-section of the both end portions of the side frame is a circle or an ellipse. The seat frame is a seat back frame;
The side frame extends in the vertical direction as the longitudinal direction,
The short direction is a front-rear direction,
The seat frame according to claim 1, wherein the both end portions include a front side portion and a rear side portion. The side frame has substantially the same size in the front-rear direction of the upper and lower parts,
6. The front-rear direction dimension of the front side part or the rear side part of the upper part is smaller than the front-rear direction dimension of the front side part or the rear side part of the lower part. Seat frame. The length of the side frame in the front-rear direction is shorter in the upper part than in the lower part,
A front-rear direction width of the front side part or the rear side part at the upper part of the side frame is larger than a front-rear direction width of the front side part or the rear side part at the lower part of the side frame. The seat frame according to claim 5.   The seat frame according to claim 7, wherein the side frame is quenched only in the upper part formed in a short length in the front-rear direction.   6. The seat frame according to claim 5, wherein a plurality of the braces are formed, and at least two of the braces extend away from each other toward the back of the seat. The seat frame is a seat back frame forming a skeleton of a backrest part,
Comprising a connecting frame that is composed of a front plate and a rear plate and connects the left and right side frames;
At least one of the front side plate and the rear side plate is formed with another hollow hole penetrating in the front-rear direction, and a erection part that is bridged over the other hollow hole,
The seat frame according to claim 1, wherein the front plate and the rear plate are joined at a lower edge of the connection frame.   11. The seat frame according to claim 10, wherein the front plate and the rear plate are joined in the vicinity of an end portion of the erection portion in the lower edge of the connection frame.   The seat frame according to claim 10, wherein the erection portion extends to a corner portion of the connection frame.   The seat frame according to claim 10, wherein the erection portion extends toward a connection portion of the connection frame with the left and right side frames. One side edge portion of the front plate or the rear plate extends toward the other so as to be bent, and is joined to the other,
A portion where the left and right side frames and the connection frame are connected is surrounded by the front plate, the rear plate, and the side edge portion to form a closed cross-sectional shape. Item 11. The seat frame according to Item 10. A guide holder for supporting a part of the headrest frame is attached to the connection frame,
The guide holder is disposed between the front plate and the rear plate,
The seat frame according to claim 10, wherein a part of the erection portion is disposed so as to overlap the guide holder in the front-rear direction.

Images