JP3099638B2 - Seat back frame - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a back frame of a seat in a vehicle such as an automobile, and a pair of sides for supporting a occupant from both sides between an upper frame portion and a lower frame portion of a frame body. The present invention relates to a seatback frame having a frame, and more particularly to a seatback frame that can be manufactured by subjecting at least an upper frame portion and a side frame to a frame material formed of a flat plate by performing press molding and bending work.

[0002]

2. Description of the Related Art Conventionally, various types of seat back frames have been proposed. For example, a seat back frame having a pair of side frames between an upper frame portion and a lower frame portion of a frame body is shown in FIG. A seat back frame having a structure as shown is known.

Here, the configuration of a conventional seat back frame will be described with reference to FIG. 20. FIG. 20 is a perspective view of a conventional seat back frame, and a seat back frame 100 basically includes an upper frame 102.
The upper frame 102 is composed of a frame body 101 integrally including a (upper frame in FIG. 20) and a lower frame 103 (lower frame in FIG. 20), and a pair of side frames 104 attached to an upper frame 102.

[0004] Here, the frame body 101 is formed by connecting one hollow pipe to each of the two first bent portions 1 through a bender.
01A, the second bent portion 101B, and the third bent portion 101C are formed by bending into a predetermined seatback shape (a substantially square shape that is symmetrical as shown in FIG. 20). , The upper frame 102 is constituted by a portion above each third bending portion 101C, and the lower frame 103 is formed by each third bending portion 10C.
A pair of lower pipes 103A bent inward from 1C,
103B. And each lower pipe 1
The edges of 03A and 103B are butted against each other and fixed by welding.

[0005] Each side frame 104 is formed by fixing both ends of a pair of support wires by welding at positions opposing each other in the upper frame 102, and the side frames 104 allow the occupant to hold the occupant on both sides. This is to support from.

Further, the right side frame 10 in FIG.
4, a reclining bracket 105 for attaching a reclining device is fixed by welding to a lower position (a lower right position of the upper frame 102). The lower part of the left side frame 104 in the figure (the lower left part of the upper frame 102)
A hinge plate 106 constituting a hinge for reclining the seat back in cooperation with the reclining device is fixed by welding.

Two pairs of S spring clamps 108 for attaching S springs 107 for elastically supporting a cushion pad (not shown) are provided on the inner surface of the upper frame 102 on which the side frames 104 are provided. Are fixed by welding. And two S springs 107
A pair of S-spring clamps 109 (one S-spring in FIG. 20) are attached between two pairs of S-spring clamps 108 and another S-spring 107 is formed integrally with the hinge plate 106 and the reclining bracket 105. (Only the spring clamp 109 is shown).

A pair of headrest brackets 110 for attaching a headrest (not shown) are fixed to the horizontal portion of the main body frame 101 above the upper frame 102 by welding.

Next, a method of manufacturing the seat back frame 100 having the above-described structure will be described. First, a hollow pipe is bent left and right symmetrically by a bender to form the frame main body 101 at the two first bending portions 101A, the second bending portion 101B, and the third bending portion 101C, three places each, a total of six places. Can be Subsequently, each third bending portion 101C
A pair of lower pipes 103A, 10B bent inward from
The edges of 3B are butted against each other and secured by welding. Thereby, the frame main body 101 is formed.

Further, two pairs of S spring clamps 108 and each side frame 104 are fixed by spot welding to the respective inner surfaces of the frame body 101 at positions opposing each other to the upper frame 102. At the lower right position of the upper frame 102, the reclining bracket 105 is fixed by arc welding, and at the lower left position of the upper frame 102, the hinge plate 106 is fixed by welding. Thereafter, a pair of headrest brackets 110 are fixed by welding in a horizontal portion of the frame main body 101 above the upper frame 102.

After the above operation, two S springs 107 are further provided.
Is mounted between two pairs of S spring clamps 108, and another S spring 107 is mounted between a pair of S spring clamps 109 formed integrally with the hinge plate 106 and the reclining bracket 105, respectively. Can be Thereby, the seat back frame 10
0 is completed.

[0012]

However, in the conventional seat back frame 100, the frame body 1
Since a pair of side frames 104, a reclining bracket 105, a hinge plate 106, and an S-spring clamp 108 are required as components attached to the frame body 101 separately from the frame body 101, the seat back frame 100 is configured. Therefore, the number of components increases, and the total cost of each component becomes extremely high, resulting in an increase in cost. Also, the side frame 104
And other components are fixed to the frame main body 101 by welding, so that the number of welding steps increases, the assembly cost for assembling the seat back frame 100 rises, and the cost increases further due to the large number of components. There is a problem.

Further, since the number of welding points for welding each component to the frame main body 101 increases, it is difficult to accurately maintain the mounting accuracy between the components, and therefore, the reclining device for the seat back frame 100 is required. When there is a connection, there is a possibility that troubles such as a failure to smoothly perform the reclining rotation operation may occur based on a mounting error inevitably generated between the components.

Further, in addition to the conventional example shown in FIG. 20, for example, Japanese Utility Model Publication No. Hei 3-21638 discloses that a pair of flat side frame plates are fixedly provided on the side of the seat back frame. A zigzag spring is installed between two pairs of spring clamp members attached to the inside of each side frame plate, and a vehicle seat is further provided with a hinge plate for a reclining device fixed to one side frame plate. Although described, each side frame plate, spring clamp member, hinge plate in such a vehicle seat,
Each of them is formed separately from the seat back frame, and therefore, it is necessary to fix parts such as the side frame plates by welding or the like, and the same problems as described above still remain. Things.

Further, Japanese Utility Model Publication No. 3-50785 discloses that
A seatback frame in which a skeleton of a seatback frame is formed by joining two side frames formed in a flat plate shape by spot welding or the like, and S springs are installed between locking holes formed in each side frame. ing. However, in such a seat back frame, although the number of parts as a whole can be reduced, each side frame is formed separately, and each side frame is joined to each other by spot welding or the like. The strength of the entire frame is not sufficient, and a welding step for each side frame is required, so that the processing is still troublesome and the problem of cost increase remains. Further, the upper frame portion formed by joining the side frames is formed in a flat plate shape, and thus cannot have sufficient strength to counter the torsional moment applied to the seat back frame. For this reason, when the driver or the like puts his weight on one of the right and left ends of the upper portion of the seat back, the seat back is greatly twisted.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems. By forming the main components of the seat back frame from a flat frame material, the number of parts and the number of assembly steps are reduced. It is an object of the present invention to provide a seat back frame capable of reducing costs and reducing costs, and having sufficient strength while maintaining accurate accuracy between components.

[0017]

To achieve the above object, a first invention according to the present invention is as follows.
In a seat back frame having a frame body composed of an upper frame portion and a lower frame portion, and a pair of side frames formed on the frame body between the upper frame portion and the lower frame portion and supporting a seated person from both sides. The upper frame portion and each side frame of the frame main body are formed by bending a frame material integrally punched from a flat plate by press working, and the upper frame portion is formed of each side frame.
A rising portion extending continuously upward from the upper end of the
And a horizontal part that connects each rising part through a bent part
And is formed in a pipe shape of a closed section having a slit, and is provided at a plurality of locations of the horizontal portion and at each of the bending portions.
Edge of the slit has the configuration which is welded to each other are.

Further, as described in claim 2, wherein the slits are formed in continuous manner to the inner surface of the upper frame. Further, as described in claim 3 and claim 4, wherein two recesses are formed in the upper frame section, that have been welded headrest bracket at four points of the respective recess and each recess . Further, as described in claim 5, the edge portion of the slit are welded in correspondence with prior Symbol respective bent portions and the respective recess, the slit connecting portions are Shape
Has been established. Furthermore, as described in claim 6, each of the side frames has a mounting portion connected to a reclining device.

Further, as set forth in claim 7, an insertion hole is formed in one of the side frames, and the lower frame portion is formed of a pipe, and one end of the pipe is connected to the other side frame. The other end of the pipe is welded and fixed to one of the side frames at a position where the pipe is inserted through the insertion hole until the interval between the side frames corresponds to a predetermined width of the seat back frame.

[0020] As described in claim 8, the lower frame portion extends from a lower end of each of the side frames and has a pair of first lower members formed in a closed cross-section pipe shape having a slit. Are formed by welding and fixing the respective end portions to each other. As described in claim 7, a cushion pad disposed on the seat back frame, a seat cover covering the cushion pad, and a locking member attached to the seat cover and provided with a locking portion. A first engaging portion that is attached to the seat cover in proximity to the locking member and that engages with the slit of the first lower member and a second engaging portion that is engaged with the locking portion of the locking member. And a seat cover is attached to the seat back frame via the locking member and the engaging member.

Further, the second invention according to the present application is a tenth invention.
As described in the above, the upper frame portion, the lower frame portion, the connecting portion formed at one end of the upper frame portion and connected to the reclining device, between the other end of the upper frame portion and one end of the lower frame portion And a side frame formed to support the occupant from one side, and the connecting portion, the upper frame portion, the side frame, and the lower frame portion bend a frame material integrally punched from a flat plate by pressing. The lower frame portion is formed by processing, and the other end of the lower frame portion is welded and fixed to the connecting portion.

Further, according to a third aspect of the present invention, as set forth in claim 11, a frame main body including an upper frame portion and a lower frame portion, and a frame main body between the upper frame portion and the lower frame portion are provided. In a seat back frame having a pair of side frames formed and supporting a seated person from both sides, the upper frame portion includes a first upper member extending from an upper end of one side frame and a second upper frame. A second upper member extending from an upper end, and a third upper member connecting the first upper member and the second upper member,
The one side frame and the first upper member, and
The other side frame and the second upper member are formed by bending a frame material integrally punched out from a flat plate by press working, and the third upper member is formed of the first upper member and the second upper member. Each is fixed by welding.

The lower frame portion may include a second lower member extending from a lower end of one side frame and a third lower member extending from a lower end of the other side frame. It comprises a lower member and a fourth lower member connecting the second lower member and the third lower member, and the fourth lower member is welded and fixed to each of the second lower member and the third lower member.

[0024]

In the seat back frame according to the first to third aspects of the present invention, a seat back is formed by combining a cushion pad and a seat cover covering the cushion pad. When the occupant sits on the seat, the occupant is supported from both sides of the seat back via a pair of side frames formed on the frame body between the upper frame portion and the lower frame portion.

At this time, in the first invention, the upper frame portion of the frame main body and each side frame in the seat back frame are both formed by bending a frame material integrally punched from a flat plate by pressing. in addition, the upper frame portion, each Saidofu
A rising part extending upward from the upper end of the frame, and
And a horizontal part that connects each rising part through a bent part
And is formed in a pipe shape with a closed cross section having slits .
Since the rim end portions are welded to each other , the upper frame portion and each side frame can be formed simultaneously from one frame material without being formed separately from each other and fixed by welding, Also, even when the load of the occupant is biased to the seat back frame,
The upper frame portion can prevent the seat back from being significantly torsionally deformed against the torsional moment generated by the load of the occupant, based on the high rigidity of the pipe structure. Further, since the number of parts is small and the number of welding steps is small, cost reduction can be realized.

Further, the slit of the upper frame A <br/> Tsu superframe is a continuous formed on the inner surface Tei Runode, bending can bending direction of the frame member with a small step to a constant in the same direction next, also, it becomes possible to easily perform the bending of the upper frame, it is possible to easily perform secure precision bending almost eliminate the twisting of the upper frame. Further, since each headrest bracket is welded and fixed at four locations of two recesses formed in the upper frame portion, the headrest bracket can be firmly fixed to the upper frame portion.

Further, the slit in the inner surface of the upper frame is welded at four positions corresponding to the bent portion and each recess that put the upper frame, thereby slit
The joints are formed so that even if the load of the occupant is unevenly applied to the upper part of the seat back frame, the number of welding points is reduced and the seat back frame is efficiently torsionally deformed. Can be prevented.

Further, each side frame is formed with a mounting portion which is connected to the reclining device. With respect to mounting the seat back frame to the reclining device, the mounting member of the reclining device formed separately is welded or the like. Accordingly, there is no need to attach the device to the seat back frame, and the number of components can be reduced. Further, since the mounting portion of the reclining device is also formed by integral pressing, the positional accuracy is high and the reclining device allows the seat back to be reclined smoothly.

An insertion hole is formed in one of the side frames, one end of a pipe serving as a lower frame portion is fixed by welding to the other side frame, and the other end of the pipe has a gap between the side frames. It is welded and fixed to one side frame at a position inserted into the insertion hole until it corresponds to a predetermined width of the seat back frame, and according to this configuration, the distance between the side frames is adjusted and the width of the seat back frame is adjusted. Variations in direction can be absorbed.

Further, the lower frame portion extends from the lower end of each side frame, and welds and fixes the respective edges of a pair of first lower members formed into a pipe having a closed cross section having a slit. With this configuration, the lower frame portion can be formed integrally with the upper frame portion and each side frame, and therefore, the number of components can be reduced from this point as well.

A seat cover for covering the cushion pad is attached to the seat back frame by cooperation of a locking member and an engaging member respectively attached to the seat cover, and a slit of each first lower member is formed. The seat cover can be attached to the seat back frame by utilizing.

Further, in the second invention, the frame body comprising the upper frame portion and the lower frame portion constituting the seat back frame, the connecting portion connected to the reclining device, and the side frame are formed by pressing a flat plate. Since the seat back frame is formed by bending the frame material punched integrally, the lower frame part and the connecting part are fixed by welding.
The members constituting the seat back frame are integrally formed, so that the number of parts can be reduced.

[0033] In the third invention, the upper frame portion of the frame main body comprises a first upper member, a second upper member, and a third upper member, and one of the side frames and the first upper member among the side frames. And the other side frame and the second upper member are formed by bending a frame material that has been integrally punched by press working, and each of the first upper member and the second upper member are interposed via the third upper member. The seat back frame is formed by welding and fixing the two upper members. By dividing the upper portion in this way, it is possible to correspond to a seat back frame of a seat back having various widths.

Further, similarly to the upper portion, the lower frame portion has a second lower member extending from one side frame, a third lower member extending from the other side frame, and a second lower member and a second lower member. When divided into three members of the fourth lower member connecting the third lower member, it becomes possible to form each lower member integrally with each side frame,
The number of parts can be reduced.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, a seat back frame according to a first embodiment will be described with reference to FIGS. 1 is a perspective view of the seat back frame according to the first embodiment, FIG. 2 is a front view of the seat back frame, FIG. 3 is a side view of the seat back frame, and FIG.
FIG. 5 is an explanatory view showing a state in which a frame material serving as an upper frame and a pair of side frames and a frame material of a lower frame are subjected to material removal from raw materials by pressing.
Is an explanatory view showing a state in which an upper frame and each side frame are formed from a frame material by bending, FIG. 6 is a perspective view of a seat back frame before fixing a lower frame, and FIG. 7 is a fixing portion for fixing a headrest bracket by welding. FIG.

1 to 3, the seat back frame 1 is composed of a frame main body 2 formed in a substantially rectangular shape. The frame main body 2 is composed of an upper frame 3, an upper part of the seat back frame 1, and a seat back frame. 1 has a lower frame 4 that constitutes a lower portion, and a pair of side frames 5 formed between the upper frame and the lower frame 4.

As described later, the upper frame 3 and the side frames 5 are made of a first frame member 20 integrally stamped from a thin plate such as a flat iron plate by pressing.
The upper frame 3 is formed in the shape of a pipe having a closed section having a slit 6 and each side frame 5 is formed in a flat plate shape. As shown in FIGS. 1 and 3, the slit 6 is formed continuously at a substantially central portion of the inner surface of the upper frame 3. Thus, the slit 6 is formed on the inner surface of the upper frame 3. Accordingly, the bending process of the upper frame 3 can be performed in a small number of steps with the bending direction of the upper frame 3 being the same direction. In addition, when the bending process of the upper frame 3 is performed, the upper frame 3 is accurately formed without twisting. 3 can be performed. Each side frame 5 supports a seated person sitting on the seat back from both sides of the seat back frame 1. The lower frame 4 has a first frame, as described later.
When removing the frame material 20 from the raw material, the second frame material 21 that is simultaneously removed is bent into a pipe shape, and the lower frame 4 is formed of a pipe. Is fixedly welded to a mounting portion 7 which is bent at the lower end of the mounting member 7.

The upper frame 3 extends horizontally from the upper ends of the side frames 5 to the rising portions 3A extending upward in FIG. 1 and the respective rising portions 3A through the bending portions 3B. It comprises a horizontal portion 3C connected in the direction. Recesses 9 (see FIGS. 2 and 3) for fixing a headrest bracket 8 that supports a pair of headrests (not shown) are formed in the horizontal portion 3 </ b> C. Are fixed by welding. Each of these headrest brackets 8
As will be described later (see FIG. 7), each recess 9 is welded and fixed at four places. Furthermore, each bending part 3B, and
The edge of the slit 6 of the upper frame 3 corresponds to the portion where the concave portions 9 are provided in the horizontal portion 3C.
As shown in FIG. 7, the slit connecting portions 10 are formed by welding to each other. These slit connecting portions 10 are for imparting high torsional rigidity to the upper frame 3, and even when a load is biased toward the upper portion of the seat back via the occupant, The seat back is reliably prevented from tilting greatly.

Further, each of the side frames 5 is formed continuously from the lower end of each rising portion 3A of the upper frame 3, and is formed around the flat plate portion 5A with the flat plate portion 5A and the slit 6 opened. Peripheral wall 5B. Further, a reinforcing bead 5C is formed on the flat plate portion 5A. The peripheral wall 5B and the reinforcing beads 5C formed on the flat plate portion 5A are both for strengthening the rigidity of the flat plate portion 5A. The flat plate portion 5A of each side frame 5 has S spring clamps 11 formed by cutting and raising the flat plate portion 5A inward at three places. A book S spring 12 is attached.

At the lower portion of each side frame 5, a reclining attachment portion 13 for attaching a reclining device (not shown) is integrally formed, and a nut 13B is provided in an attachment hole 13A of each reclining attachment portion 13.
Are fixed by welding (see FIG. 3). The reclining mounting portion 13 has a mounting hole 13A, a nut 1
A reclining device is attached via 3B.

Next, a method of manufacturing the seat back frame 1 having the above-described configuration will be described with reference to FIGS. First, as shown in FIG. 4, a first frame member 20 for integrally forming the upper frame 3 and each side frame 5 and a second frame member 21 for forming the lower frame 4 are formed in a flat plate shape. The material is taken out from the raw material by being stamped together by press working.

At this time, the material of the second frame member 21 is removed from the gaps formed between the first frame members 20 by utilizing the shape of the first frame member 20, thereby saving the raw material. . In addition, during material removal, the first
The portion of the frame material 20 where each side frame 5 is formed is punched out in a size that includes a bending allowance for forming the peripheral wall 5B in a later step, and each side frame 5 has three portions. "U" shaped hole forming the S spring clamp 11 and the reclining attachment part 1
A third mounting hole 13A is punched out.

Next, drawing is performed on the entire periphery of the first frame member 20 to form a peripheral wall 5B around each side frame 5 as shown in FIG. A wall is also formed for the portion. At the same time as the drawing, both ends (lower ends) of the side frames 5 are bent to form the mounting portions 7. Further, the S spring clamp 11 is formed by bending.

Subsequently, as shown in FIG. 5 (C), the wall formed on the portion to be the upper frame 3 is bent round into a pipe shape, and the upper frame 3 is formed into a pipe shape with a closed cross section.

Thereafter, two bent portions 3B are formed in the upper frame 3 via a bender processing machine to provide a rising portion 3A and a horizontal portion 3C.
A recess 9 for attaching the headrest bracket 8 is formed at a location. This state is shown in FIG. Then, both ends of the lower frame 4 obtained by pipe-working the second frame member 21 are fixed to the mounting portions 7 formed at the lower end of each side frame 5 by welding.

Further, a pair of headrest brackets 8 are fitted into the respective recesses 9 of the horizontal portion 3C (see FIG. 3), and are fixed by welding at four places of the respective recesses 9 by spot welding. A method of welding and fixing each of the headrest brackets 8 and each of the recesses 9 will be described with reference to FIG. Here, FIG. 7A is a perspective view of the horizontal portion 3C showing the concave portion 9 in an enlarged manner.
7 (B) is a plan view showing FIG. 7 (A) viewed from the direction of arrow A, and FIG. 7 (C) is a side view showing FIG. 7 (A) as viewed from arrow B.

In each of the figures, the concave portion 9 is formed by pressing the pipe-shaped horizontal portion 3C in the lateral direction, and welding portions 9A and 9B are provided on the upper and lower sides of the concave portion 9, respectively.
In addition, in each of the welds 9A, 9B, a separation groove 9C,
9D is formed, and a portion between the welds 9A and 9B enters the inside of the horizontal portion 3C. Such recess 9
When the pipe-shaped headrest bracket 8 is fitted to
The headrest bracket 8 comes into contact with each of the welding portions 9A and 9B at two locations on both sides of each of the separation grooves 9C and 9D. Therefore, if spot welding is performed with the headrest bracket 8 fitted in the recess 9, the headrest bracket 8 is welded and fixed at four locations of the recess 9. When the headrest bracket 8 and the recess 9 are welded and fixed by spot welding as described above, the welding and fixing of the two can be performed in an extremely short time, and the headrest bracket 8 is fixed at four points in the recess 9. Therefore, it is possible to prevent the headrest bracket 8 from accidentally coming off the recess 9 based on the above.

After the pair of headrest brackets 8 are fixed to the respective recesses 9 by welding as described above, the upper frame 3 corresponds to the portions where the respective recesses 9 are provided in the bent portions 3B and the horizontal portions 3C. The edges of the slits 6 are welded and fixed to each other to form a slit connecting portion 10.
High torsional rigidity is imparted to the upper frame 3 through each of the slit connecting portions 10, so that even when a load is applied to the upper portion of the seat back via the occupant, the seat back is large. Inclination can be reliably prevented. Then, three S springs 12
Are attached between the S spring clamps 11, whereby the seat back frame 1 is completed.

Next, the operation of the seat back frame 1 having the above configuration will be described.
The seat back is formed by combining a cushion pad and a seat cover that covers the cushion pad. When the occupant sits on the seat, the occupant is supported from both sides of the seat via a pair of side frames 5 formed between the upper frame 3 and the lower frame 4.

As described above in detail, in the seat back frame 1 according to the first embodiment, the upper frame 3 and the side frames 5 of the frame body 2 of the seat back frame 1 are integrally formed by pressing from a flat plate. Since the punched first frame member 20 is formed by bending, the first frame member 20 having a flat plate shape is formed.
Of the seat back frame 1 such as the upper frame 3, the respective side frames 5, the S spring clamp 11, the reclining attachment portion 13, and the like, whereby the number of parts and the number of assembly steps of the seat back frame 1 can be increased. And the cost can be easily reduced.

The upper frame 3 is formed in the shape of a pipe having a closed cross section having a slit 6, and the upper frame 3 corresponds to the portion where each concave portion 9 is provided in each bent portion 3B and horizontal portion 3C. 3 slits 6
Are welded and fixed to each other to form the slit connecting portion 10, so that even when the load of the occupant is applied to the seat back frame 1 unevenly, the upper frame 3 has a plurality of slits. Through the high rigidity provided based on the connecting portion 10, it is possible to prevent the seat back from being greatly torsionally deformed against the torsional moment generated by the load of the occupant.

The slit 6 is provided in the upper frame 3
The slits 6 are formed on the inner surface of the upper frame 3 in such a manner that the upper frame 3 is bent in the same direction by a small number of steps. Frame 3
In addition, when the upper frame 3 is bent, the upper frame 3 can be bent accurately without twisting.

Further, since each headrest bracket 8 is welded and fixed at each of four welding portions 9A and 9B in two concave portions 9 formed in the horizontal portion 3C of the upper frame 3, the upper frame 3 , The headrest bracket 8 can be firmly fixed.

Each of the side frames 5 is integrally formed with a reclining attachment portion 13 which is connected to the reclining device. With respect to the attachment of the seat back frame 1 to the reclining device, the reclining device is formed separately. It is not necessary to attach the attachment member to the seat back frame 1 by welding or the like at all. Therefore, in this respect, the number of parts can be reduced and the cost can be reduced. Further, since the reclining attachment portion 13 is formed by integral press working, the reclining operation can be smoothly performed when the seat back 1 is reclined by the reclining device with high positional accuracy.

Further, the peripheral wall 5B is formed over the entire periphery of the flat plate portion 5A in each side frame 5, and the reinforcing beads 5C are formed on the flat plate portion 5A.
It is possible to reliably prevent each side frame 5 from being deformed when an external force is applied. Further, the reclining device is attached to the reclining attachment portion 13 provided on each of the side frames 5 of the seat back frame 1, so that the side frames 5 which are flat plates are formed.
The rigidity of is enhanced.

It should be noted that the present invention is not limited to the first embodiment, but various improvements and modifications are of course possible.

For example, in the first embodiment, the edges of the slits 6 of the upper frame 3 correspond to the bent portions 3B of the upper frame 3 and the portions where the recesses 9 are provided in the horizontal portion 3C. Although the slit connection portion 10 is formed by welding and fixing to each other to increase the torsional rigidity of the upper frame 3, the rigidity of the upper frame 3 can be increased by other methods.

This method will be described with reference to FIGS. Here, FIG. 8 is a plan view showing another example of a frame material serving as an upper frame and each side frame,
9 is a perspective view of a seat back frame before fixing a lower frame formed using the frame material of FIG.
0 is an explanatory view showing a bending state of the upper frame in the seat back frame of FIG. 9, and FIG. 11 is an explanatory view showing another bending state of the upper frame in the seat back frame of FIG. In the following description, the description will be made with a focus on differences from the first embodiment, and the same members and the like as in the first embodiment will be described with the same reference numerals. Shall be.

First, as shown in FIG. 8, a third frame member 23 for forming the upper frame 3 and the side frames 5 is taken from a raw material. In FIG. 8, the third
The frame member 23 is provided with joining pieces 24 and 25 at positions (two locations on both sides) corresponding to the bent portions 3B of the upper frame 3 in a portion where the upper frame 3 is formed.
Are formed, and joining pieces 26 and 27 are formed at positions (two inner positions) corresponding to the respective concave portions 9. Here, the joint pieces 24, 25, 26, and 27 are welded and fixed to each other when the upper frame 3 is bent into a pipe shape. As shown in FIG. 10, the portion of the upper frame 3 in which 26 and 27 are not present has an open lower surface and a substantially U-shaped cross section. The other configuration has the same configuration as that of the first embodiment.

When the third frame member 23 is bent by the same method as in the first embodiment,
The main body of the seat back frame 1 (without the lower frame 4) as shown in FIG. 9 is obtained. FIG. 10 shows a bending state of the upper frame 3 in the body of the seat back frame 1. In FIG. 10, the horizontal portion 3C of the upper frame 3 has a lower surface (FIG. 10).
The upper surface of the upper frame 3 is formed in a substantially “U” shape, and at positions corresponding to the bent portions 3B of the upper frame 3 and the recesses 9 (to which the headrest brackets 8 are fixed by welding), The joining pieces 24 to 27 are bent and welded to each other to form a pipe having a closed cross section. The rising portion 3A of the upper frame 3
As shown in FIGS. 9 and 10, each is formed in a shape gradually opened toward each side frame 5.

As described above, the joint pieces 24 to 27 are respectively formed at the portions corresponding to the bent portions 3 B and the concave portions 9 in the third frame member 23, and the joint pieces 24 to 27 are formed at the time of bending the upper frame 3. By bending and welding each other, the rigidity at each bent portion 3B and each concave portion 9 of the upper frame 3 can be further improved.

In the case of forming the upper frame 3 and each side frame 5 using the third frame member 23, as shown in FIG. 11, the horizontal portion 3C of the upper frame 3 is different from the case of FIG. Similarly, the lower surface (FIG. 1)
1, the upper surface of the upper frame 3 is formed in a substantially “U” shape, and each bent portion 3B of the upper frame 3 and each concave portion 9 are formed.
At a position corresponding to (the headrest bracket 8 is fixed by welding), each of the joining pieces 24 to 27 may be bent into a cylindrical shape and welded to each other to form a cylindrical pipe having a closed cross section.

As described above, the joint pieces 24 to 27 are respectively formed at the portions corresponding to the bent portions 3 B and the concave portions 9 in the third frame member 23, and the joint pieces 24 to 27 are formed at the time of bending the upper frame 3. By bending into a cylindrical shape and welding to each other, the rigidity of each bent portion 3B and each concave portion 9 of the upper frame 3 can be improved in the same manner as described above.

As another modification of the first embodiment, as shown in FIG. 12, an insertion hole 7A is formed in one of the mounting portions 7 (the mounting portion 7 on the left side in FIG. One end (the right end in FIG. 12) is fixedly welded to the other mounting portion 7 (the right mounting portion 7 in FIG. 12), and the other end (the left end in FIG. 12) of the lower frame 4 has a predetermined width of the seat back frame 1. After the insertion hole 7A is inserted until it corresponds, it may be welded and fixed. According to such a configuration, variations in the width direction that occur when the seatback frame 1 is formed can be absorbed and finely adjusted. Here, FIG.
FIG. 2 is a front view showing another modification of the first embodiment.

The slit connecting portion 10 may be formed by welding over the entire edge of the slit 6 in the upper frame 3.

Next, a second embodiment of the present invention will be described with reference to FIG.
15 through FIG. Here, FIG. 13 is a perspective view of the seat back frame according to the second embodiment, FIG. 14 is an explanatory view showing a state in which the fourth frame material forming the seat back frame is bent, and FIG. It is sectional drawing which shows the lower part of the comprised seat back typically. In the following description, the description will focus on the points different from the seat back frame 1 of the first embodiment.

In FIG. 13, the seat back frame 3
1 includes a frame main body 32 formed in a substantially square shape, and the frame main body 32 includes a seat back frame 31.
The upper frame 33 includes an upper frame 33 that forms an upper portion of the seat back frame 31, a lower frame 34 that forms a lower portion of the seat back frame 31, and a pair of side frames 35 formed between the upper frame 33 and the lower frame 34.

As described later, the upper frame 33, the side frames 35, and the lower frame 34 are provided on a fourth frame member 44 integrally punched from a thin plate such as a flat iron plate by pressing. The upper frame 33 and the lower frame 34 are formed in a pipe shape of a closed cross section having a slit 36, and each side frame 35 is formed in a flat plate shape. . Each of these side frames 35 supports a seated person sitting on the seat back from both sides of the seat back frame 31.
The lower frame 34 is composed of a pair of lower members 34A extending from the lower ends of the side frames 35, and the ends of the lower members 34A are fixed to each other by welding.

The upper frame 33 extends horizontally from the upper end of each side frame 35 to a rising portion 33A extending upward in FIG. 13 and a horizontal portion between the rising portions 33A via the bending portions 33B. It comprises a horizontal portion 33C connected in the direction. A headrest bracket (not shown) supporting a pair of headrests is provided on the horizontal portion 33C.
A concave portion 39 for fixing the concave portion 3 is formed.
9, a headrest bracket is fixed by welding. Each of these headrest brackets is
Through the same method as in the embodiment, four recesses 39 are welded and fixed. Further, each bending portion 3
In the same manner as in the first embodiment, the edges of the slits 36 of the upper frame 33 are welded to each other at the slit connection portions ( (Not shown). These slit connecting portions are for imparting a high torsional rigidity to the upper frame 33, and even when a load is applied to the upper portion of the seat back via the occupant, the seat connection is increased. A large inclination of the back is reliably prevented.

Further, each of the side frames 35 is formed continuously from the lower end of each of the rising portions 33A of the upper frame 33.
Is opened to form a peripheral wall 35 formed around the flat plate portion 35A.
B. Further, a reinforcing bead (not shown) is formed on the flat plate portion 35A, and the peripheral wall 35B and the reinforcing bead formed on the flat plate portion 35A are both for reinforcing the rigidity of the flat plate portion 35A. , And is the same as the first embodiment. Further, the flat plate portions 35A of each side frame 35 are provided at three places.
The S spring clamp 41 is formed by cutting and raising A inward, and each of these three pairs of S spring clamps 41 is formed.
Are mounted with three S springs (not shown).

At the lower part of each side frame 35, a reclining attachment portion 43 for attaching a reclining device (not shown) is integrally formed, and a nut is welded and fixed to an attachment hole 43A of each reclining attachment portion 43. ing. A reclining device is attached to the reclining attachment portion 43 via an attachment hole 43A and a nut. The configuration of the reclining attachment portion 43 is formed in the same manner as in the first embodiment.

Next, a method of manufacturing the seat back frame 31 according to the second embodiment having the above-described configuration will be described with reference to FIG. First, as shown in FIG. 14A, the upper frame 33, each side frame 35,
In addition, the fourth frame member 44 for integrally forming the lower frame 34 is punched out of a flat plate-like raw material by press working to collect the material. At the time of such material removal, a portion forming each side frame 35 in the fourth frame member 44 is punched in a size including a bending allowance for forming the peripheral wall 35B in a later process,
Also, each side frame 35 has S
A “U” shaped hole forming the spring clamp 41 and a mounting hole 43A of the reclining mounting portion 43 are punched out. This point is the same as that of the first frame member 20 in the first embodiment.

On the other hand, on both sides of the portion forming each side frame 35, a portion serving as a lower member 34A forming the lower frame 34 is integrally formed, whereby the upper frame 33, each side frame 35,
The lower frame 34 is formed integrally from the same fourth frame member 44 at the same time. This is different from the first embodiment in which the lower frame 4 is formed separately and fixed to the mounting portion 7 by welding.

Next, drawing is performed on the entire periphery of the fourth frame member 44 to form a peripheral wall 35B around each side frame 35 as shown in FIG. A wall is also formed for the portion. At the same time as the drawing, a wall is similarly formed in a portion constituting each lower member 34A. Further, the S spring clamp 41 is formed by bending.

Subsequently, as shown in FIG. 14 (C), the wall formed on the part to be the upper frame 33 and the part to be each lower member 34A of the lower frame 34 are rounded into a pipe shape. Thereby, the upper frame 3 and the lower frame 34 are formed in a pipe shape with a closed cross section.

Thereafter, two bent portions 33B are formed in the upper frame 33 via a bender processing machine to provide a rising portion 33A and a horizontal portion 33C. Further, a headrest bracket is attached to two portions of the horizontal portion 33C. Recess 39 is formed. Then, after each lower member 34A formed at the lower end of each side frame 35 is bent through the bent portion 33D, the ends of each lower member 34A are welded and fixed to each other.

After that, the headrest bracket is welded and fixed to each of the concave portions 39 of the horizontal portion 33C, and a slit connection is made to a portion of the horizontal portion 33C corresponding to each concave portion 39 and a portion corresponding to the bent portion 33B. Although a portion is formed, the method of welding and fixing the headrest bracket and the method of forming the slit connecting portion are performed in the same manner as in the first embodiment, and thus the description thereof is omitted here.

The seat back frame 31 formed as described above forms a seat back by combining a cushion pad and a seat cover covering the cushion pad. A configuration in which the seat cover is attached using the lower frame 34 when the seat back is formed as described above will be described with reference to FIG.

In FIG. 15, the seat back 45 is provided with a cushion pad 46 via S springs attached between the S spring clamps 41 in the seat back frame 31, and the cushion pad 46 is attached to the seat cover 47. It is constituted by covering with. Also,
A lower frame 34 is arranged below the seat back 45, and a slit 36 formed in the lower frame 34 is opened at an obliquely upper position.

In the vicinity of the lower frame 34,
A locking member 48 is attached to the inside of the seat cover 47 by sewing, and the locking member 48 has a length covering substantially the entire area of the seat back 45 in the width direction. Further, the locking member 48 is formed with a locking portion 48A having a “U” shape in side view.

Further, the locking portion 48A of the locking member 48
The engaging member 49 is attached to the seat cover 47 by sewing in the same manner as the locking member 48, and the engaging member 49 has a length equivalent to the locking member 48 and 45 are provided over almost the entire area in the width direction. Further, the engagement member 49 side of the lower frame 34 (FIG. 15)
A first engagement portion 49A that engages with the slit 36 of the lower frame 34 is integrally formed on the middle left side), and a locking member 48 is provided on the locking member 48 side (the right side in FIG. 15). A second engagement portion 49B that engages with the stop portion 48A is formed.

According to such a configuration, the seat cover 47 can be attached through the slit 36 formed in the lower frame 34 constituting the seat back frame 31.

As described above, in the seat back frame 31 according to the second embodiment, the upper frame 33, the side frames 35, and the lower frame 34 can be simultaneously formed integrally from one fourth frame member 44. Therefore, the number of parts constituting the seat back frame 31 can be reduced, and the number of assembly steps can be reduced to reduce the cost.

The seat cover 47 covering the cushion pad 46 is provided with a locking portion 48A and a locking member 49 of a locking member 48 attached to the seat cover 47, respectively.
The first engagement portion 49A, the second engagement portion 49B, and the slit 36 of the lower frame 34 cooperate to securely and easily attach the seat back frame 31 to the lower frame 34.

Next, a third embodiment will be described with reference to FIGS.
It will be described based on. Here, FIG. 16 is a perspective view showing a seat back frame according to the third embodiment, and FIG. 17 is an explanatory view showing a state in which a fifth frame material constituting the seat back frame is bent. In the following, description will be made with a focus on differences from the first embodiment.

In FIG. 16, the seat back frame 5
1 includes a frame main body 52 formed in a substantially square shape, and the frame main body 52 includes a seat back frame 51.
An upper frame 53 constituting an upper part of the seat back frame 51, a pipe-shaped left frame 65 formed continuously with the upper frame 53 on the left side of the seat back frame 51 and provided with a reclining attachment portion 63 for attaching a reclining device at a lower end thereof. A lower frame 54 constituting a lower portion of the seat back frame 51, and an upper frame 5 on the right side of the seat back frame 51;
3 and one side frame 55 formed between the lower frame 54.

Here, the reclining attachment portion 63, the left frame 65, the upper frame 53, the side frames 55, and the lower frame 54 are integrally punched from a thin plate such as a flat iron plate by press working as described later. The fifth frame member 64 is formed integrally and simultaneously by performing a predetermined bending process.
3, the lower frame 54 and the left frame 65 are formed in a pipe shape of a closed section having a slit 56, and the side frame 55 is formed in a flat plate shape.
The side frames 55 support a seated person sitting on the seat back from one side of the seat back frame 51. The lower frame 54 extends from the lower end of the side frame 55, and the end of the lower frame 54 is fixed to the reclining attachment portion 63 by welding.

The upper frame 53 is provided with a rising portion 53A extending upward from FIG. 16 continuously from the upper end of the side frame 55 and the left frame 65, and a rising portion 53A through each bending portion 53B. It consists of a horizontal portion 53C connecting the spaces in the horizontal direction. Horizontal part 53
A concave portion 59 for fixing a headrest bracket (not shown) for supporting a pair of headrests is formed in C, and the headrest bracket is fixed to each concave portion 59 by welding. Each of these headrest brackets is welded and fixed at four places in each recess 59 through the same method as in the first embodiment. Further, the edges of the slits 56 of the upper frame 53 are welded to each other corresponding to the portions where the concave portions 59 are provided in the bent portions 53B and the horizontal portions 53C, as in the first embodiment. Slit connection (not shown)
Are formed. These slit connection portions are for imparting a high torsional rigidity to the upper frame 53, so that even when a load is biased toward the upper portion of the seat back via the occupant, the seat connection is increased. A large inclination of the back is reliably prevented.

Further, the side frame 55 is formed continuously from the lower end of the rising portion 53A on one side (right side) of the upper frame 53, and the flat portion 55A and the slit 56 are opened to surround the flat portion 55A. And the peripheral wall 55B formed at the bottom. In addition, the flat plate portion 5
5A is formed with a reinforcing bead (not shown), and the peripheral wall 55B and the reinforcing bead formed on the flat plate portion 55A are
Both of them are for enhancing the rigidity of the flat plate portion 55A, as in the first embodiment. Further, the flat plate portion 55A of the side frame 55 is formed with an S spring clamp 61 by cutting and raising the flat plate portion 55A inward at three places, and the left frame 65 corresponds to each S spring clamp 61. Thus, three clamp members 66 are attached. And, between each S spring clamp 61 and each clamp member 66, three S springs are provided.
A spring (not shown) is attached.

The reclining attachment portion 63 is provided with a mounting hole 63A to which a nut is welded and fixed, and the reclining device is attached to the reclining attachment portion 63 via the attachment hole 63A and the nut. . The configuration of the reclining attachment portion 63 is formed in the same manner as in the first embodiment. Thus, according to the seat back frame 51 of the third embodiment, it is possible to cope with a seat back in which the reclining device is connected to one side.

Next, a method of manufacturing the seat back frame 51 according to the third embodiment having the above-described configuration will be described with reference to FIG. First, as shown in FIG. 17A, the reclining attachment portion 63, the left frame 65,
The fifth frame member 64 for integrally forming the upper frame 53, the side frame 55, and the lower frame 54 is blanked from a flat plate-shaped raw material by pressing to collect the material. At the time of such material removal, a portion of the fifth frame member 64 where the side frame 55 is formed is punched out in a size including a bending allowance for forming the peripheral wall 55B in a later step. A "U" -shaped hole forming an S spring clamp 61 and a mounting hole 63A of the reclining mounting portion 63 are punched out at three places. This point is the same as that of the first frame member 20 in the first embodiment.

Further, the portion forming the lower frame 54 is formed integrally with the portion forming the side frame 55. This is different from the first embodiment in which the lower frame 4 is formed separately and fixed to the mounting portion 7 by welding.

Next, drawing is performed on the entire periphery of the fifth frame member 64 to form a peripheral wall 55B around the side frame 55 and the upper frame 53 as shown in FIG. Walls are also formed in parts. At the same time as the drawing, walls are formed in the same manner for the portion forming the left frame 65, the portion forming the reclining attachment portion 63, and the portion forming the lower frame 54. Further, the S spring clamp 61 is formed by bending.

Subsequently, as shown in FIG. 17 (C), the wall formed on the portion forming the left frame 65, the wall formed on the portion forming the upper frame 53, and the wall formed on the portion forming the lower frame 54. Then, the wall is bent round into a pipe shape, whereby the left frame 65, the upper frame 53 and the lower frame 54 are formed into a pipe shape having a closed cross section.

Thereafter, two bent portions 53B are formed in the upper frame 53 via a bender processing machine to provide a rising portion 53A and a horizontal portion 53C, and further, a headrest bracket is attached to two portions of the horizontal portion 53C. Recess 59 is formed. After the member formed at the lower end of the side frame 35 is bent through the bent portion 53D, the end of the lower frame 54 is fixed to the reclining attachment portion 63 by welding.

After that, the headrest bracket is welded and fixed to each of the concave portions 39 of the horizontal portion 33C, and furthermore, a slit connection is made to a portion of the horizontal portion 33C corresponding to each concave portion 39 and a portion corresponding to the bent portion 33B. Although a portion is formed, the method of welding and fixing the headrest bracket and the method of forming the slit connecting portion are performed in the same manner as in the first embodiment, and thus the description thereof is omitted here. Also, three clamp members 66 are attached to the left frame 65, and thereafter, the side frames 55
Spring clamps 61 and clamp members 6 provided on the
Three S springs are attached between the six.

As described above, in the seat back frame 51 according to the third embodiment, the reclining attachment portion 63 and the left frame 6 constituting the seat back frame 51 are provided.
5. The upper frame 53, the side frame 55, and the lower frame 54 are formed by bending a fifth frame member 64 integrally punched from a flat plate by pressing, and reclining and attaching the end of the lower frame 54. The seat back frame 51 is fixed by welding to the portion 63.
The seat back frame 51
Can be integrally formed to reduce the number of parts. Further, according to the seat back frame 51, it is possible to support a one-side reclining device.

Next, a seat back frame according to a fourth embodiment will be described with reference to FIGS. Here, FIG. 18 is a perspective view of the seat back frame excluding the lower frame according to the fourth embodiment, and FIG. 19 is a perspective view showing a seat back frame according to another modification of the fourth embodiment.

In FIG. 18, the seat back frame 7
1 comprises a frame main body 72 formed in a substantially square shape, and the frame main body 72 includes a seat back frame 71.
The upper frame 73 includes an upper frame 73, an upper frame 73, a lower frame (not shown) that configures a lower portion of the seat back frame 71, and a pair of side frames 75 formed between the upper frame 73 and the lower frame.

Here, the upper frame 73 extends from the upper end of one of the side frames 75 (the left side frame 75 in FIG. 18) and is formed integrally with the horizontal portion 73C via the bent portion 73B. Upper member 73A,
A second upper member 73 extending from the upper end of the other side frame 75 (the right side frame 75 in FIG. 18) and integrally formed with the horizontal portion 73F via the bent portion 73E.
D, and a third upper member 73G welded and fixed to each end of each of the horizontal portions 73C and 73F. The third upper member 73G is formed of a pipe having a closed cross section having a slit. In the third upper member 73G, two recesses 79 for fixing a headrest bracket are formed as in the above-described embodiments. The brackets are welded and fixed at four locations in each recess 79 through the same method as in the first embodiment.

The left side frame 75 and the first upper member 73A, and the right side frame 75 and the second upper member 73D are each a frame integrally punched from a thin plate such as a flat iron plate. The upper frame 73 is formed in a pipe shape of a closed section having a slit 76, and each side frame 75 is formed in a flat plate shape by performing a predetermined bending process on a material (not shown). Is formed.
Each of these side frames 75 supports a seated person sitting on the seat back from both sides of the seat back frame 71.

The lower frame is made of a pipe as in the first embodiment, and is formed by welding both ends of the pipe to mounting portions 77 provided at the lower end of each side frame 75.

Further, the bent portion 7 of the first upper member 73A
3B, the bent portion 73E of the second upper member 73D, and
The slits 7 of the upper frame 73 correspond to the portions where the concave portions 79 are provided in the third upper member 73G.
The edge of No. 6 and the edge of the slit of the third upper member 73G are welded to each other to form a slit connecting portion (not shown) as in the first embodiment. These slit connection portions are for imparting a high torsional rigidity to the upper frame 73, and even when a load is applied to the upper portion of the seat back via the occupant, the seat connection is increased. A large inclination of the back is reliably prevented.

Each of the side frames 75 has a first
The lower end of the upper member 73A and the second upper member 7
It is formed continuously from the lower end of 3D, and has a flat plate portion 75A.
And a peripheral wall 75B formed around the flat plate portion 75A with the slit 76 opened. Further, a reinforcing bead (not shown) is formed on the flat plate portion 75A, and the peripheral wall 75B and the reinforcing bead formed on the flat plate portion 75A are both for reinforcing the rigidity of the flat plate portion 75A. , And is the same as the first embodiment. The flat plate portion 75A of each side frame 75 has S spring clamps 81 formed by cutting and raising the flat plate portion 75A inward at three places.
Three S springs (not shown) are attached to the spring clamp 81.

At the lower portion of each side frame 75, a reclining attachment portion 83 for attaching a reclining device (not shown) is integrally formed, and a nut is welded and fixed to an attachment hole 83A of each reclining attachment portion 83. ing. A reclining device is attached to the reclining attachment portion 83 via an attachment hole 83A and a nut. The configuration of the reclining attachment portion 83 is formed in the same manner as in the first embodiment.

The seat back frame 71 constructed as described above is manufactured by the same method as in the first and second embodiments. Therefore, the manufacturing method is described in each of the first embodiment. For example, reference is made to the manufacturing method of the second embodiment, and description thereof is omitted here.

As described above, in the seat back frame 71 according to the fourth embodiment, the upper frame 73 of the frame body 72 is composed of the first upper member 73A, the second upper member 73D, and the third upper member 73G. Side frame 7 on one side (left side) of frame 75
5 and the first upper member 73A, and the other (right side) side frame 75 and the second upper member 73D are formed by bending a frame material that has been integrally punched by press working. Upper member 73
The seat back frame 71 is formed by welding and fixing each of the first upper members 73A and the second upper members 73D via the G, and the sheets having various widths are formed by dividing the upper frame 73 in this manner. It can correspond to the back seat back frame.

Next, another modified example of the fourth embodiment will be described with reference to FIG. In this modification, the lower frame 84 is formed by fixing the lower frame 84 by welding the both ends of the pipe to the respective mounting portions 77 in the same manner as the first embodiment. The feature is that it is divided into lower members. The other configuration is the same as that of the fourth embodiment shown in FIG. 18, and the description is omitted here.

That is, in FIG. 19, the upper frame 73 includes the first upper member 73A and the second upper member 73.
D, corresponding to being divided into three members of the third upper member 73G, the lower frame member 84 is integrated from the lower end of one (left side) side frame 75 to the horizontal portion 84C via the bent portion 84B. 1st lower member 8 formed in
4A, a second lower member 84D extending from the lower end of the other (right) side frame 75 and integrally formed with the horizontal portion 84F via a bent portion 84E, and each horizontal portion 84C.
The third lower member 84G is welded and fixed to each end of 84F. The third lower member 84G is formed of a closed-section pipe having a slit.

As described above, according to the modification shown in FIG. 19, similarly to the upper frame 73, the lower frame 84 is provided with the first lower member 84A extending from one (left) side frame 75 and the other ( Right side frame 7
5 and a third lower member 84G connecting the first and second lower members 84A and 84D to each other.
In addition to 3A and 73D, each of the lower members 84A and 84D can be formed integrally with each of the side frames 75, whereby the number of components constituting the seat back frame 71 can be reduced and cost can be reduced. .

[0111]

As described above, according to the present invention, the main components of the seat back frame are formed from the frame material formed in a flat plate shape, so that the number of parts and the number of assembling steps can be reduced and the cost can be reduced. As well as
It is possible to provide a seat back frame capable of providing sufficient strength while maintaining accurate accuracy between the components, and the industrial effect is great.

[Brief description of the drawings]

FIG. 1 is a perspective view of a seat back frame according to a first embodiment.

FIG. 2 is a front view of a seat back frame.

FIG. 3 is a side view of the seat back frame.

FIG. 4 is an explanatory diagram showing a state in which a frame material serving as an upper frame and a pair of side frames and a frame material of a lower frame are subjected to material removal from raw materials by pressing.

FIG. 5 is an explanatory diagram showing a state in which an upper frame and each side frame are formed from a frame material by bending.

FIG. 6 is a perspective view of the seat back frame before the lower frame is fixed.

FIG. 7 is an explanatory view showing a fixing portion for fixing the headrest bracket by welding.

FIG. 8 is a plan view showing another example of a frame material serving as an upper frame and each side frame.

9 is a perspective view of a seat back frame before fixing a lower frame formed using the frame material of FIG. 8;

FIG. 10 is an explanatory view showing a bending state of an upper frame in the seat back frame of FIG. 9;

FIG. 11 is an explanatory diagram showing another bending state of the upper frame in the seat back frame.

FIG. 12 is a front view showing another modification of the first embodiment.

FIG. 13 is a perspective view of a seat back frame according to a second embodiment.

FIG. 14 is an explanatory diagram showing a state in which a fourth frame member forming the seat back frame is bent.

FIG. 15 is a cross-sectional view schematically illustrating a lower portion of a seat back including a seat back frame.

FIG. 16 is a perspective view showing a seat back frame according to a third embodiment.

FIG. 17 is an explanatory view showing a state in which a fifth frame material forming the seat back frame is bent.

FIG. 18 is a perspective view of a seat back frame excluding a lower frame according to a fourth embodiment.

FIG. 19 is a perspective view showing a seat back frame according to another modification of the fourth embodiment.

FIG. 20 is a perspective view of a conventional seat back frame.

[Explanation of symbols]

 1, 31, 51, 71 Seat back frame 2, 32, 52, 72 Frame body 3, 33, 53, 73 Upper frame 4, 34, 54, 84 Lower frame 5, 35, 55, 75 Side frame 6, 36, 56, 76 Slit 8 Headrest bracket 9, 39, 59, 79 Recess 10 Slit connecting part 11, 41, 61, 81 S spring clamp 12 S spring 13, 43, 63, 83 Reclining attachment part 20 First frame material 21 Second Frame material 23 Third frame material 44 Fourth frame material 64 Fifth frame material

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-6-70827 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) A47C 7/40

Claims (12)

(57) [Claims] 1. A frame body comprising an upper frame portion and a lower frame portion, and a pair of side frames formed on the frame body between the upper frame portion and the lower frame portion and supporting a seated person from both sides. In the seat back frame having, the upper frame portion and each side frame of the frame main body are formed by bending a frame material integrally punched out from a flat plate by press working, and the upper frame portion is formed of a side frame. The top
Rising part and bending continuously extended upward from
Consists of a horizontal section that connects each rising section through the section
Both are formed in a pipe shape with a closed cross section having a slit, and are formed at a plurality of locations of the horizontal portion and at each of the bending portions.
Seat back frame edge of the serial slit, characterized in that it is welded to one another. 2. A seat back frame according to claim 1, wherein said slit is characterized by Tei Rukoto is continuous formed on the inner surface of the upper frame. 3. The seat back frame according to claim 2, wherein two recesses are formed in the upper frame portion, and a headrest bracket is fixed to each of the recesses by welding. 4. The seat back frame according to claim 3, wherein each of the headrest brackets is welded and fixed at four positions of each of the concave portions. 5. The edge of the slit are welded in correspondence with prior Symbol respective bent portions and the respective recess, the slit connecting portions are Shape
Seat back frame according to claim 3, characterized in that it is made. 6. The seat back frame according to claim 1, wherein a mounting portion connected to a reclining device is formed on each of the side frames. 7. An insertion hole is formed in one of the side frames, and the lower frame portion is formed of a pipe. One end of the pipe is welded and fixed to the other side frame, and 2. The seat according to claim 1, wherein the other end of the seat is welded and fixed to one of the side frames at a position inserted into the insertion hole until the interval between the side frames corresponds to a predetermined width of the seat back frame. Back frame. 8. The lower frame portion extends from a lower end of each of the side frames and welds and fixes each end of a pair of first lower members formed into a pipe having a closed cross section having a slit. The seat back frame according to claim 1, wherein the seat back frame is formed by: 9. A cushion pad provided on the seat back frame, a seat cover for covering the cushion pad, a locking member attached to the seat cover and provided with a locking portion, and a proximity to the locking member. And an engagement member formed with a first engagement portion engaged with the slit of the first lower member and a second engagement portion engaged with the engagement portion of the engagement member. Has,
The seat back frame according to claim 8, wherein the seat cover is attached to the seat back frame via a locking member and an engaging member. 10. An upper frame portion, a lower frame portion, a connecting portion formed at one end of the upper frame portion and connected to the reclining device, and formed between the other end of the upper frame portion and one end of the lower frame portion. And a side frame that supports the occupant from one side, and the connecting portion, the upper frame portion, the side frame, and the lower frame portion are formed by bending a frame material integrally punched from a flat plate by pressing. A seat back frame, wherein the other end of the lower frame portion is welded and fixed to the connecting portion. 11. A frame body comprising an upper frame portion and a lower frame portion, and a pair of side frames formed on the frame body between the upper frame portion and the lower frame portion and supporting a seated person from both sides. In the seat back frame, the upper frame portion includes a first upper member extending from an upper end of one side frame, a second upper member extending from an upper end of the other side frame, and a first upper member. A third upper member for connecting the second upper member to the second upper member, wherein the one side frame and the first upper member;
The other side frame and the second upper member are formed by bending a frame material integrally punched out of a flat plate by press working, and the third upper member is formed of the first upper member and the second upper member. A seat back frame which is fixedly welded to each. 12. The lower frame portion includes a second lower member extending from a lower end of one side frame, a third lower member extending from a lower end of the other side frame, and a second lower member.
A fourth lower member connecting the lower member and the third lower member, wherein the fourth lower member is welded and fixed to each of the second lower member and the third lower member. 11
The described seat back frame.