JP5880319B2 - Seat frame - Google Patents

Description

  The present invention relates to a seat frame. Specifically, the present invention relates to a seat frame that integrally includes a pair of left and right side frames, a connecting frame that connects ends of the pair of side frames, and a bridging frame that is provided across the pair of side frames.

  2. Description of the Related Art Conventionally, as a frame structure of a vehicle seat, a structure in which a side frame of a seat back is divided into a forked shape in front and rear is known (Patent Document 1). Specifically, the side frame has a thick steel plate material fitted between the lower ends of the bifurcated branch frame, and this iron plate material has a structural strength that is connected to the seat cushion via the recliner. It is set as the structure in which the high coupling | bond part was formed.

German Patent Application Publication No. 10 2008 037 323

  However, in the above prior art, an iron plate material having a high structural strength is attached only to the lower end portion of the side frame, and the structural strength of the seat frame is not sufficiently increased. The present invention was devised to solve the above problems, and the problem to be solved by the present invention is to increase the structural strength of a seat frame having a bifurcated frame structure.

In order to solve the above problems, the seat frame of the present invention takes the following means.
A first invention is a seat frame that integrally includes a pair of left and right side frames, a connecting frame that connects the ends of the pair of side frames, and a bridge frame that is provided between the pair of side frames. It is. At least one of the side frames has a cross section that is bifurcated and widened. The end of the bridging frame joined to at least one side frame opened in a bifurcated shape is integrally joined to each of the branch frames divided into the bifurcated shape of the side frame. It is provided as.

  According to the first aspect of the present invention, the ends of the bridging frame are integrally coupled across the branch frames of at least one of the side frames that are divided into two forks. The structural strength of each branch frame is preferably increased by the structural strength. In this way, by providing a bridging frame that spans between the side frames so as to be integrally coupled across the branch frames, the seat frame having a bifurcated frame structure is provided. The structural strength can be increased.

  According to a second aspect of the present invention, in the first aspect described above, the ends of the bridging frame provided between the branch frames are divided into bifurcated shapes and applied separately to the branch frames and coupled. Is.

  According to the second aspect of the invention, the end of the bridging frame is divided into two forks, and is separately applied to each branch frame so as to be coupled to each branch frame without greatly bending the bridging frame. The shape of the frame can be made perfect. In addition, the load applied to each branch frame is directly applied to and supported by the main body portion of the bridge frame that is bridged between the side frames. Therefore, the structural strength of each branch frame can be further increased.

  According to a third aspect of the present invention, in the second aspect described above, at least one of the branch portions of the end portion of the bridging frame that is divided into two forks is opened outwardly from a position inside the area between the positions of the branch frames. It extends so as to open and is connected to each branch frame.

  According to the third aspect of the present invention, each branch portion of the end portion of the bridging frame that is divided into two forks is provided so as to be brazed between each branch frame and the bridging frame. As a result, the load applied to each branch frame is relatively strongly supported by the main body of the bridge frame bridged between the side frames, and the structural strength of each branch frame can be further increased.

It is an external appearance perspective view of the vehicle seat to which the seat frame of Example 1 was applied. It is a perspective view of a seat frame simple substance. It is a front view of a seat frame. It is a side view of a seat frame. It is the VV sectional view taken on the line of FIG. FIG. 6 is a sectional view taken along line VI-VI in FIG. 4. It is the perspective view which showed the state before the bending process of a side frame. It is the perspective view which showed the state which bent the side frame. It is the perspective view which showed the state which opened and extended the side frame into the forked shape. It is the perspective view which showed the state before attaching a bridge | crosslinking frame to a seat frame. It is the XI-XI sectional view taken on the line of FIG. FIG. 6 is a cross-sectional view illustrating a schematic configuration of a seat frame of Example 2.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated using drawing.

  First, the configuration of the seat frame according to the first embodiment will be described with reference to FIGS. As shown in FIG. 1, the “seat frame” of the present embodiment is configured as a seat back frame 10 that forms a framework of the seat back 2 of the vehicle seat 1 configured as a passenger seat of an automobile. Here, the vehicle seat 1 includes a seat back 2 that serves as a backrest for a seated occupant, a seat cushion 3 that serves as a seating portion, and a headrest 4 that serves as a headrest portion.

  The seat back 2 has a disc-shaped reclining device (not shown) in which the lower end portions on both the left and right sides function as a rotation shaft device capable of stopping rotation with respect to the rear end portions of the left and right sides of the seat cushion 3. Connected to each other. Thus, the seat back 2 is connected to the seat cushion 3 so that the backrest angle can be adjusted. The seat cushion 3 is connected to a vehicle floor via a pair of left and right slide devices (not shown). Thereby, the seat cushion 3 is in a state provided so as to be able to adjust the position in the front-rear direction with respect to the floor. The basic structure of the reclining device and slide device (not shown) is the same as that disclosed in the literatures such as Japanese Patent Application Laid-Open No. 2011-116303 and Japanese Patent Application Laid-Open No. 2010-221935. Detailed description will be omitted.

  The headrest 4 is mounted on the upper portion of the seat back 2. Specifically, the headrest 4 has two rod-like stays protruding from the lower part thereof in two rectangular tube-shaped holders 13 fixed on an upper frame 12 of a seat back frame 10 described later. By being inserted into a cylindrical support member (not shown) that is mounted and mounted from above, the cylindrical support member is mounted and fixed on the upper part of the seat back 2. In addition, the structure which inserts and installs the stay (not shown) of the headrest 4 in each holder 13 fixed to the seat back frame 10 is the same as that disclosed in a document such as Japanese Patent Application Laid-Open No. 2008-239075. Therefore, a specific description thereof will be omitted.

  Hereinafter, a specific configuration of the seat back frame 10 will be described with reference to FIGS. As shown in FIGS. 2 to 4, the seat back frame 10 includes a side frame 11 having a bifurcated side frame 11 that forms a skeleton on both the left and right sides of the seat back 2, and a skeleton on the upper portion of the seat back 2. A panel member comprising an upper frame 12 formed, two rectangular tube-shaped holders 13 coupled to two positions on the upper frame 12, and high-tensile steel plates coupled to lower ends of the side frames 11, respectively. 14 and a horizontally long plate-like bridged panel 15 spanned between the lower portions of the side frames 11. Here, the upper frame 12 corresponds to the “joining frame” of the present invention, and the bridge panel 15 corresponds to the “bridge frame” of the present invention.

  The seat back frame 10 is formed as follows. First, as shown in FIG. 7, one extruded material of aluminum alloy is formed, and this is bent into an inverted U-shape by press working so that the side frames 11 and the upper frame 12 described above are connected together. To form a frame material of the shape At this time, prior to the above-described bending or after the bending, the side frames 11 are provided with cuts 11C for opening and spreading them in a bifurcated manner later (cutting process). In addition, notches 12A for inserting the holders 13 from the front side of the seat later are also made at locations where the holders 13 on the upper frame 12 are joined (see FIG. 9) (notch process). By inserting the notches 11C and the notches 12A at this stage (the stage in which the seat back frame 10 is not bent in the front-rear direction), the work of inserting each of the notches 11C is a straightforward and simple processing operation. At the same time, since it becomes easy to set the seat back frame 10 on a jig for cutting when the notches 12A are inserted, the processing becomes easy. Each cut 11C is straightly inserted in the height direction from a position near the upper end of each side frame 11 to a position penetrating to the lower end side. In addition, you may make it insert each notch 11C and notch 12A mentioned above after all the bending processes and opening processes which the seat back frame 10 mentions later are completed.

  Next, as shown in FIG. 8, the intermediate portions of the side frames 11 are each bent into a bow-like shape on the rear side of the seat by pressing (bending step). Specifically, the branch frames 11A and 11B arranged on the front and rear sides separated by the cuts 11C of the side frames 11 are pressed together so as to be pushed together and bent toward the seat rear side. As a result, the branch frames 11A and 11B are pushed and bent into a curved shape so as to have the same shape in the front-rear direction as the arrangement direction thereof, and the bent shapes match each other at the intermediate portion. Shaped bent portions 11A2 and 11B2 are formed.

  Next, as shown in FIG. 9, the front branch frames 11B of the folded side frames 11 are bent so as to open and spread to the front side of the seat with respect to the rear branch frames 11A. Unfolding process). Specifically, the front branch frames 11B are bent with respect to the rear branch frames 11A so that the upper ends serving as the start points of these branches are opened to the front side of the seat. Thereby, each side frame 11 is formed in a shape that is bifurcated in the front-rear direction, and is formed in a shape in which the front-rear width of the shape gradually increases from the upper end side toward the lower end side; Become.

  Next, a panel member 14 made of a high-strength steel plate is inserted into each open end portion of each side frame 11 that is widened and assembled together (assembly step). Furthermore, each holder 13 is fitted on each notch 12A notched on the upper frame 12 in the previous step, and integrally joined by welding. Next, as shown in FIG. 10, the bridge panel 15 is bridged between the lower portions of the side frames 11 and integrally joined by welding. Here, each end portion 15B of the bridge panel 15 is formed such that the upper edge portion and the lower edge portion are cut and raised to the front side with respect to the central portion, and the bent upper edge is formed. Each branch portion 15B2 composed of a portion and a lower edge portion and a central branch portion 15B1 are formed in a bifurcated shape. Each of the end portions 15B of the bridge panel 15 is welded so that each central branch portion 15B1 is abutted against and welded to the inner surface of the branch frame 11A on the rear side of each side frame 11. Each branch portion 15B2 with the edge branching is abutted against and welded to the inner surface of the branch frame 11B on the front side of each side frame 11. Thereby, each edge part 15B of the bridge | crosslinking panel 15 is set as the state integrally provided straddling between each branch frame 11A, 11B of each side frame 11, respectively. As shown in FIGS. 2 to 4, the seat back frame 10 is formed of an extruded material of an aluminum alloy, and both side frames 11 are opened in a bifurcated shape to reduce the weight. The structural strength is appropriately increased by inserting each panel member 14 and bridging the bridge panel 15.

  Next, the configuration of each part of the seat back frame 10 will be described in detail. As shown in FIG. 5, the seat back frame 10 includes a first cross-sectional portion 10 </ b> A having a closed cross-sectional shape and a second cross-sectional portion having a closed cross-sectional shape formed by extrusion molding of the above-described aluminum alloy. 10B are formed in a cross-sectional shape formed by connecting them in the front-rear direction. As described above with reference to FIG. 7, when the seat back frame 10 is bent into an inverted U shape, the second cross-sectional portion 10 </ b> B is positioned on the front side and the first side on the rear side when the seat back frame 10 is folded into an inverted U shape. The cross section 10A is formed by being bent in a direction perpendicular to the arrangement direction so that the positional relationship is maintained. Thereby, the seat back frame 10 is formed in a state in which the cross section of each side frame 11 and the cross section of the upper frame 12 have the same shape from the inner periphery side to the outer periphery side of the seat back frame 10. It is supposed to be in a state.

  As shown in FIG. 5, the first cross-sectional portion 10A includes a flat mounting surface portion 10A1 facing the front side of the seat, and an endless crossing extending from each edge of the mounting surface portion 10A1 to the rear side of the seat. It has a reinforcing surface portion 10A2 having a surface shape, and is formed in a cross-sectional shape closed endlessly by these. Specifically, the mounting surface portion 10 </ b> A <b> 1 is formed in a flat surface shape whose surface is inclined obliquely toward the inner peripheral side (lower side in FIG. 5) with respect to the front side of the seat back frame 10.

  The second cross-sectional portion 10B includes a connecting surface portion 10B1 extending from the outer peripheral side (upper side in FIG. 5) edge of the seat back frame 10 of the first cross-sectional portion 10A described above to the seat front side, and the seat front of the connecting surface portion 10B1. 5 is formed in a cross-sectional shape having a closed cross-sectional portion 10B2 that extends from the side edge portion to the inner peripheral side (lower side in FIG. 5) of the seat back frame 10 and is wound to the rear side to be closed. . Between the closed cross-sectional portion 10B2 of the second cross-sectional portion 10B and the mounting surface portion 10A1 of the first cross-sectional portion 10A on the rear side thereof, on the inner peripheral side of the seat (lower side in FIG. 5) An opening 10C that opens is formed. The opening 10C is formed in such a shape that the opening shape is widened toward the inner peripheral side (lower side in FIG. 5) of the seat back frame 10 due to the inclined shape of the mounting surface portion 10A1 described above. .

  Further, a rail groove 10A3 is formed in the connecting portion between the first cross-sectional portion 10A and the connecting surface portion 10B1. The rail groove 10A3 is recessed in a pocket shape so that the cross-sectional shape of the reinforcing surface portion 10A2 is recessed on the seat rear side. The rail groove 10A3 is formed in an open sectional shape of a rectangular enclosure that opens to the front side of the seat. In addition, a rail groove 10B3 recessed in a pocket shape in which the cross-sectional shape of the closed cross-sectional portion 10B2 is recessed toward the front side of the seat is also formed at the connecting portion between the connecting surface portion 10B1 of the second cross-sectional portion 10B and the closed cross-sectional portion 10B2. Is formed. The rail groove 10B3 is formed in a rectangular enclosure-shaped open cross-sectional shape that opens to the rear side of the seat symmetrically with respect to the rail groove 10A3. These rail grooves 10A3 and 10B3 are shaped so as to communicate with each other in the front-rear direction through the opening 10C described above, that is, a shape opened to the inner peripheral side (lower side in FIG. 5) of the seat back frame 10 through the opening 10C. It is set as the structure covered from the outer peripheral side (upper side in FIG. 5) of the seat back frame 10 by the connection surface part 10B1.

  The notches 11C inserted in the side frames 11 described above with reference to FIG. 7 with respect to the seat back frame 10 described above connect the first cross section 10A and the second cross section 10B described above to the connecting surface portion 10B1 (FIG. 5). (See FIG. 6). Therefore, as shown in FIG. 6 and FIG. 9, by opening each side frame 11 in a bifurcated manner from each of the notches 11C, an opening between the first cross section 10A and the second cross section 10B. The portion 10C is opened and widened, and can be formed in a form separated from each other in the front-rear direction. As a result, the first cross section 10A opened to the rear side is used as the above-described rear branch frame 11A, and the second cross section 10B opened to the front side is used as the above-described front branch frame 11B. Each of the branch frames 11A and 11B that are formed and spread out is formed in a state having a high structural strength having a closed cross-sectional shape.

  And as shown in FIG. 9, the panel member 14 which consists of a high-tensile steel plate is inserted in the edge part of the opening side (lower side) of each side frame 11 opened in the forked shape from the sheet | seat lower side, respectively. Attached. Here, each panel member 14 made of the high-tensile steel plate has a higher specific strength than each side frame 11 made of the above-described extruded material of aluminum alloy. The panel members 14 are inserted into the end portions on the opening side of the side frames 11 opened in a bifurcated manner as described above, thereby being fitted in a wedge shape between the end portions of the branch frames 11A and 11B. Thus, it functions as a bridging material (reinforcing material) that connects them, and increases the structural strength of the open end of each side frame 11.

  Further, as shown in FIG. 1, each panel member 14 connects the lower end portions of the left and right sides of the seat back frame 10 to the rear end portions of the left and right sides of the seat cushion 3 via a reclining device (not shown). At this time, it functions as a coupling portion with the reclining device. Specifically, as shown in FIG. 2, each panel member 14 is in a state in which its surface is directed in the seat width direction when attached to the lower end portion of each side frame 11, and on the plate surface thereof. Includes a plurality of fitting holes 14A1 for coupling to the reclining device (not shown) and an axial hole 14A2 for passing an operation shaft (not shown) for performing the unlocking operation of the reclining device. It is in a state opened through.

  As shown in FIG. 9, the cylindrical projections 14 </ b> B <b> 1, which are rolled inward toward the inner peripheral side of the seat back frame 10, are formed on the front and rear edges of each panel member 14 described above. 14B2 is formed. The cylindrical projections 14B1 and 14B2 are formed in the rail grooves 11A1 and 11B1 (10A3) formed in the branch frames 11A and 11B when the panel members 14 are inserted between the branch frames 11A and 11B of the side frames 11, respectively. , 10B3) and are inserted through each of them. Specifically, the cylindrical protrusions 14B1 and 14B2 are formed in such a shape that their rolled cylinder shapes are slightly larger than the inner diameters of the rail grooves 11A1 and 11B1 (10A3 and 10B3). By being press-fitted into the rail grooves 11A1, 11B1 (10A3, 10B3), they are strongly fitted to each other and firmly engaged so as not to come off in the direction perpendicular to the insertion direction. (See FIG. 6).

  Here, as shown in FIG. 9, the branch frames 11 </ b> A and 11 </ b> B of each side frame 11 described above are formed in a bifurcated shape so as to be wider than the front and rear widths of the panel members 14. Yes. Thereby, when each panel member 14 is inserted, each cylindrical projection 14B1, 14B2 of each panel member 14 is inserted into the rail grooves 11A1, 11B1 of the branch frames 11A, 11B and engaged. Thus, the branch frames 11A and 11B are adjusted to their front and rear widths as the panel members 14 are inserted due to the engagement structure and the high structural strength of the panel members 14. Their opening width can be changed so as to be elastically compressed into the shape. Therefore, in a state where the panel members 14 are inserted and attached to the side frames 11 due to the elastic deformation of the branch frames 11A and 11B, the resilient force that the branch frames 11A and 11B attempt to restore in the opening direction, respectively. Is applied to each panel member 14, so that these elastic forces act so as to further increase the coupling force between each panel member 14 and each side frame 11, and the two are more firmly and integrally coupled. It is supposed to be held as.

  In addition, each branch frame 11A, 11B may be opened and widened so that it may become narrower than the front-back width | variety of each panel member 14 mentioned above. Even in this case, when the panel members 14 are inserted, the cylindrical protrusions 14B1 and 14B2 of the panel members 14 are inserted into the rail grooves 11A1 and 11B1 of the branch frames 11A and 11B, respectively. By inserting, the branch frames 11A and 11B are adjusted to the front and rear widths as the panel members 14 are inserted due to the engagement structure and the high structural strength of the panel members 14. Their opening width can be changed so that they can be elastically pushed into the shape. Therefore, in a state where the panel members 14 are inserted and attached to the side frames 11 due to the elastic deformation of the branch frames 11A and 11B, the resilient force that the branch frames 11A and 11B attempt to restore in the closing direction, respectively. Is applied to each panel member 14, so that these elastic forces act so as to further increase the coupling force between each panel member 14 and each side frame 11, and the two are more firmly and integrally coupled. Will be held as.

  Here, as described above, the branch frames 11A and 11B of the side frames 11 are formed by bending the intermediate portions thereof as bent portions 11A2 and 11B2, respectively, in a bow shape on the seat rear side. The shape of the region below the bent portions 11A2 and 11B2 into which the panel members 14 are inserted is a straight shape extending straight downward. Accordingly, the rail grooves 11A1 and 11B1 formed in the branch frames 11A and 11B are similarly formed in a straight shape extending straight downward. And each cylindrical protrusion 14B1 and 14B2 formed in the both sides of each panel member 14 is also formed in the straight cylindrical shape extended straightly in the height direction in the mutually substantially parallel state. Accordingly, each panel member 14 can be smoothly inserted into each side frame 11 without being replaced in the middle.

  Further, as well shown in FIG. 6, the central portion of each panel member 14 is placed on each side of the front and rear sides beside each of the front and rear edges of each panel member 14 where the cylindrical protrusions 14B1 and 14B2 are formed. Step portions 14C1 and 14C2 are formed so as to protrude outward from the edge (outer periphery side of the seat back frame 10: right side in FIG. 6). With these stepped portions 14C1 and 14C2, each panel member 14 has its cylindrical projections 14B1 and 14B2 on the front and rear sides thereof inserted into the rail grooves 11A1 and 11B1 and attached to the side frames 11, respectively. The central plate portion is assembled in a form with a sense of unity that forms a flush state with the outer surface of each branch frame 11A, 11B of each side frame 11. As shown in FIG. 9, a flange 14 </ b> D that is bent toward the inner side of the seat back frame 10 is formed at the upper edge of each panel member 14 by bending by pressing. With these flanges 14D, the structural strength against bending and twisting of each panel member 14 itself is enhanced, and the upper edge of each panel member 14 is rounded inward, thereby forming an angular shape on the outside. It is in a state where it is formed in a shape that is not exposed.

  Each panel member 14 is fitted into and integrally attached to the open end portion of each side frame 11 which is opened in a bifurcated shape, so that the open end portion of each side frame 11 is made of a member having high structural strength. In the closed state, the structural strength of the entire seat back frame 10 is effectively increased. As a result, the seat back frame 10 can strongly receive and support the backrest load received from the back of the seated occupant by the support structure in which the lower ends of the side frames 11 are supported in a cantilevered manner. ing.

  Here, each panel member 14 has a shape in which each upper edge portion formed with a plate-like flange 14D interposed between both the branch frames 11A and 11B is inclined straight in the forward obliquely upward direction. Is formed. As a result, the rate of change in the structural strength (section modulus) in the height direction of each side frame 11 that is enhanced by the mounting of each panel member 14 is moderate because the shape of each panel member 14 is inclined. It is adjusted to become. Specifically, the inclined shape of the upper edge portion of each panel member 14 is a front rising shape, whereby the load applied to the seat back frame 10 from the front side of the seat is higher by each panel member 14. It is designed to be able to receive the load from the front side of the seat that is applied to the seat back frame 10 more strongly than the one that is inclined to the opposite side (backward rising shape). .

  Accordingly, when a large load is applied to the seat back frame 10 so that the back of the seated occupant strongly presses due to the occurrence of a rear collision of the vehicle, each panel member that protrudes to a high position on the front side. 14, the large load can be strongly received and the shape of the upper edge of each panel member 14 is inclined so that the structural strength of the seat back frame 10 does not change suddenly. Thus, the large load can be widely dispersed and received in the entire seat back frame 10 without local stress concentration occurring in the seat back frame 10.

  Further, as shown in FIGS. 2 and 10, a horizontally elongated plate-like bridge panel 15 formed of an extruded material of an aluminum alloy is integrally formed between the lower portions of the side frames 11 that are opened and spread in the forked shape. It is provided in a state of being stretched over. Here, the bridging panel 15 is formed of an extruded material of an aluminum alloy, and the upper edge portion and the lower edge portion thereof are formed in a shape that is thicker than the center portion. The bridge panel 15 has a left and right end portion 15B connected to each side frame 11, and the thickened upper and lower edge portions are cut and raised to the front side of the seat. The branch portion 15B2 is connected to each branch frame 11B, and the central portion of each end portion 15B is formed to be flush with the main body portion 15A of the bridge panel 15 without being bent. Are formed as branch portions 15B1 coupled to the respective branch frames 11A.

  Each branch portion 15B1 at the center of each end portion 15B connected to each branch frame 11A on the rear side of the bridge panel 15 is abutted against the surface portion on the inner side of the seat of each branch frame 11A on the rear side, and is firmly welded. (See FIG. 6). Further, the upper edge portion and lower edge portion 15B2 of each end portion 15B of the bridging panel 15 coupled to the front branch frames 11B are obliquely outwardly forward with respect to the central branch portions 15B1. Further, the end portions of the cut and raised ends are bent outwardly of the seat and are brought into contact with the inner surface of the front branch frame 11B. Thus, they are firmly and integrally joined by welding (see FIG. 6).

  Specifically, as shown in FIG. 6, the branch portions 15B1 and 15B2 of the end portions 15B divided into the bifurcated shape of the bridging panel 15 are arranged between the branch frames 11A and 11B in the front-rear arrangement region (front side). It extends so as to open outwardly from the position inside the branch frame 11B and the rear branch frame 11A) and is abutted against each of the branch frames 11A and 11B and struts. It is assumed that it is connected. Thereby, the shape of the bridge panel 15 can be made to reach each branch frame 11A, 11B without greatly bending the bridge panel 15, and the load applied to each branch frame 11A, 11B is directly applied to the bridge panel 15. It is configured to be supported by the main body 15A. Further, the branch portions 15B1 and 15B2 of the end portions 15B divided into the forked shape of the bridging panel 15 are provided so as to be brazed between the branch frames 11A and 11B and the bridging panel 15. As a result, the load applied to each branch frame 11A, 11B is relatively strongly supported by the main body 15A of the bridge panel 15, and the structural strength of each branch frame 11A, 11B is further enhanced. It is said that.

  Specifically, as shown in FIG. 6, each of the branch frames 11 </ b> A and 11 </ b> B constituting each side frame 11 of the seat back 2 has a configuration in which the structural strength is increased by mounting the panel member 14 described above. Specifically, each branch frame 11A, 11B and each panel member 14 are coupled to each other by the roll-shaped cylindrical projections 14B1, 14B2 formed on both edge portions of each panel member 14, respectively. The rail grooves 11A1 and 11B1 (10A3 and 10B3) are coupled tightly to each other. Therefore, when a strong pressing force is applied to each side frame 11 from the rear side or from the front side, the rear branch frame 11A or the front branch frame 11B is connected to the above-described edge of the panel member 14 (cylinder). Bending force is applied such that the protrusions 14B1, 14B2) are pushed around the fulcrum. However, with respect to these branch frames 11A and 11B, the respective end portions 15B of the bridge panel 15 described above are divided into two-forks and are separately abutted and joined so as to be attached to the braces. . Thereby, each branch frame 11A, 11B is in a state of being strongly supported by the bridging panel 15 so as to be able to withstand even if the force to be pushed is applied as described above.

  More specifically, the bifurcated shape of each end 15B of the bridging panel 15 has three branches 15B2 at the upper edge and the lower edge that are cut and raised to the front side of the seat with respect to the central branch 15B1. Due to the bifurcated shape of the legs, each branch portion 15B2 is in contact with and coupled to the front branch frame 11B at two points spaced in the height direction, and at a position in the height region between them. The central branch portion 15B1 is in contact with and coupled to the rear branch frame 11A. As a result, the bridging panel 15 is firmly and integrally joined to the branch frames 11A and 11B so that the legs (branches 15B1 and 15B2) are widened in three directions and are not twisted. ing.

  Thus, according to the configuration of the seat frame (seat back frame 10) of the present embodiment, each end 15B of the bridging panel 15 is between the branch frames 11A and 11B of each side frame 11 divided into two forks. As a result of being integrally coupled across the two, the structural strength of each of the branch frames 11A and 11B can be suitably increased by the structural strength of the coupled bridge panel 15. In this way, the bridge panel 15 spanned between the side frames 11 is provided in a state of being integrally joined across the branch frames 11A and 11B, thereby dividing the frame into a bifurcated shape. The structural strength of the seat back frame 10 having a structure can be suitably increased.

  Next, the mounting structure of the holder 13 that is mounted at the two left and right positions on the upper frame 12 will be described with reference to FIGS. 9 and 11. As shown in FIG. 9, each holder 13 is formed of an extruded material of an aluminum alloy, like the seat back frame 10. These holders 13 are formed in a square cylindrical shape, and are fitted into the notches 12A formed at two positions on the left and right of the upper frame 12 and cut from the front side of the seat. 12 are firmly and integrally coupled to each other by welding.

  Here, as shown in FIGS. 9 to 11, the notches 12 </ b> A are formed so as to partially penetrate the second cross-sectional portion 10 </ b> B of the upper frame 12. The mounting surface portion 10A1 of the first cross-sectional portion 10A is exposed to the front side of the seat, which is the mounting direction side of each holder 13. As shown in FIGS. 3 and 9, the cutouts 12A are set to have the same width as that of the holders 13, and the holders 13 are inserted into the cutouts 12A on the front side of the seat. The rear surface portion of each holder 13 is applied as a state of being in surface contact with each mounting surface portion 10A1 of the upper frame 12, respectively. Further, by the above fitting, each holder 13 can be assembled in a state where the movement in the sheet width direction is restricted and restricted by the end face shape of the second cross-sectional portion 10B facing each notch 12A. Yes. After the fitting, the contact surfaces of the holders 13 and the upper frame 12 are welded and joined to each other so that they are firmly and integrally joined.

  In the above-described welding, each notch 12A described above is formed to have the same width as the width of each holder 13. Therefore, when each holder 13 is fitted into each notch 12A, these contact portions However, it will be in the state which was exposed from the outside over the whole outer periphery of each notch 12A. Specifically, as shown in FIG. 11, each notch 12A is fitted to each notch 12A and brought into surface contact with each mounting surface portion 10A1, as shown in FIG. The edge portion is cut out so as to be in contact with the rear surface portion of each holder 13. Therefore, when the holders 13 are assembled in the notches 12, all the contact portions of the two exposed to the outside can be welded, and by welding all of them, they are welded with a wide welding length. In a tightly integrated state.

  By the way, as described above with reference to FIG. 9, each mounting surface portion 10 </ b> A <b> 1 of the upper frame 12 that is assigned to the state in which the above-described holders 13 are in surface contact with each other, By being bent and formed into an arcuate shape, the seat back frame 10 is normally straight to the front side of the seat in a situation where the seat back frame 10 is used in a posture inclined to the rear side of the seat slightly from the vertical direction. The surface is directed in a state close to (see FIG. 11). Therefore, each holder 13 can be supported by the surface straight from the rear side of the seat in each mounting surface portion 10A1, and the load from the front side of the seat on the headrest 4 (see FIG. 1) can be favorably supported by the upper frame 12. Can be.

  Further, as described above, the seat back frame 10 has a shape in which the intermediate portion of each side frame 11 is curved in the shape of a bow on the rear side of the seat (bending portions 11A2 and 11B2). Each side frame 11 is formed at both side positions so that the shape of each side frame 11 protrudes greatly toward the front side of the seat, and a side support portion that can support the waist of the seated occupant from both outsides is set large, or The lumbar portion can be strongly supported at a position on the front side of the seat. Further, the seat back frame 10 has a shape in which both side frames 11 are warped to the rear side of the seat, so that a wider space can be secured for a passenger sitting in the rear seat to throw out his / her foot forward. It can be configured.

  Next, the configuration of the seat frame (seat back frame 10) of Example 2 will be described with reference to FIG. In the present embodiment, portions having substantially the same configuration and operation as those of the seat frame (seat back frame 10) shown in the first embodiment are denoted by the same reference numerals, description thereof is omitted, and different portions are provided. Will be described in detail. In this embodiment, the branch portions 15B1 and 15B2 of the end portions 15B divided into the bifurcated shape of the bridging panel 15, and the branch frames 11A and 11B of the side frames 11 divided into the bifurcated shape of the seat back 2 and The joint structure is a press-fit joint structure.

  Specifically, the front end portions (fitting portions 15B1a and 15B2a) of the branch portions 15B1 and 15B2 of the bridging panel 15 are respectively provided below the seat on the peripheral surface portions of the branch frames 11A and 11B on the seat back side. Rail grooves 11A3 and 11B3 having a cross-sectional enclosure shape that can be inserted and press-fitted from the side are formed, and the end portions of the branch portions 15B1 and 15B2 of the bridging panel 15 are press-fitted into the rail grooves 11A3 and 11B3. Thus, fitting portions 15B1a and 15B2a are formed which are strongly fitted to the rail grooves 11A3 and 11B3 so as not to come off. These fitting portions 15B1a and 15B2a are formed in a cross-sectional shape slightly larger than the inner diameter of each rail groove 11A3 and 11B3, and are press-fitted into each rail groove 11A3 and 11B3, thereby being strongly fitted to these. As a result, they are firmly and integrally joined so as not to come off in a direction perpendicular to the insertion direction. These rail grooves 11A3 and 11B3 may be formed by connecting different members to the branch frames 11A and 11B, or may be formed together by extrusion molding of the side frames 11. . The branch portions 15B1 and 15B2 of the bridging panel 15 are press-fitted into the rail grooves 11A3 and 11B3 of the branch frames 11A and 11B, and are further welded to be firmly and integrally joined. May be.

  As mentioned above, although embodiment of this invention was described using two Examples, this invention can be implemented with various forms other than the said Example. For example, in the above-described embodiment, the seat back frame 10 is illustrated as the “seat frame” of the present invention, but the “seat frame” of the present invention can also be applied as a frame of other seat structures such as a seat cushion. It is something that can be done. The “seat frame” of the present invention is not only made of an extruded material of an aluminum alloy, but also by various methods such as a pressed material, an extruded material, a forged material made of various metal materials such as a magnesium alloy and a steel material. What is formed can be applied.

  In addition, the cross-sectional shape of the “branch frame” that is opened in a bifurcated shape of the “side frame” is not limited to a particular shape, and various cross-sections can be used regardless of whether they are closed or open. What is formed in a shape can be applied in combination. In the above-described embodiment, the seat back frame 10 (seat frame) is illustrated in which the upper frame 12 and the side frames 11 are formed in a single shape by the extruded material, but these are formed separately from each other. Then, it may be integrally joined and assembled later. Similarly, the “cross-linking frame” of the present invention is not limited to a specific shape, and may be applied to various cross-sectional shapes regardless of a closed cross section or an open cross section. It can be done.

  In addition, the “crosslinking frame” of the present invention may be anything that is joined across “each branch frame” with respect to “at least one side frame” that is shaped to be opened in a bifurcated manner. In addition to the “end part” of the “cross-linking frame” divided into bifurcated shapes and applied separately, the “end part” of the “cross-linking frame” is not divided into bifurcated shapes. "Bridges that are formed with a width spanning between them" or that are joined by being folded so that the entire "ends" of the "bridge frame" are bridged in order to "each branch frame" There may be. Further, the connection between the “bridging frame” and the “branch frame” of the “side frame” may be a connection by bonding or fastening in addition to the connection by welding or press-fitting as shown in the above embodiments. .

  Further, the “bridge frame” is configured to be coupled across “branch frames” that are opened in a bifurcated manner in “at least one side frame” of the pair of left and right “side frames”. Any shape may be used, and the shape of the “other side frame” and the coupling structure therefor may be any. In addition, the “branches” of the “each end portion” divided into two forks of the “bridge frame” are out of the position where the “branch frame” is located outside the area between the branch frames. It may extend so as to open in an open manner, and may be applied to “each branch frame” and coupled. In addition, the shape of the “end portion” divided into the bifurcated shape of the “crosslinking frame” may be two legs, four legs or more in addition to those branched in three legs as shown in the above embodiments. The shape may be branched into shapes.

DESCRIPTION OF SYMBOLS 1 Vehicle seat 2 Seat back 3 Seat cushion 4 Headrest 10 Seat back frame (seat frame)
DESCRIPTION OF SYMBOLS 10A 1st cross-sectional part 10A1 Mounting surface part 10A2 Reinforcement surface part 10A3 Rail groove 10B 2nd cross-sectional part 10B1 Connecting surface part 10B2 Closed cross-section part 10B3 Rail groove 10C Opening part 11 Side frame 11A Branch frame 11A1 Rail groove 11A3 Bending part 11A2 Bending part 11A2 Branch frame 11B1 Rail groove 11B2 Bending part 11B3 Rail groove 11C Cut 12 Upper frame (connection frame)
12A notch 13 holder 14 panel member 14A1 fitting hole 14A2 shaft hole 14B1 cylindrical projection 14B2 cylindrical projection 14C1 stepped portion 14C2 stepped portion 14D flange 15 bridged panel (bridged frame)
15A body part 15B end part 15B1 branch part 15B1a fitting part 15B2 branch part 15B2a fitting part

Claims (2)

A seat frame that integrally includes a pair of left and right side frames, a connecting frame that connects the ends of the pair of side frames, and a bridging frame that is provided across the pair of side frames,
At least one of the side frames is formed in a shape in which the cross section is bifurcated and spread,
End portions of the bridging frame joined to at least one side frame opened in a bifurcated shape are integrally joined to each of the branch frames divided into a bifurcated shape of the side frame. It is provided as a state ,
An end portion of the bridging frame provided between the branch frames is divided into two forks, and is separately applied to and coupled to the branch frames. The seat frame according to claim 1,
Each branch portion of the end portion of the bridging frame that is divided into two forks extends from the position inside the area between the positions of the branch frames so that at least one of the branch frames opens obliquely and is coupled to the branch frames. A seat frame characterized by being made.

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