Vehicle seat

Abstract

A vehicle seat (1) comprises a seat back that has an upper part tiltable with respect to a lower part, and that is capable of favorably deploying an airbag. A seat back frame (10) constituting the skeleton of a seat back (5) has a base frame (11), and a movable frame (12) rotatably coupled to the base frame (11). The base frame (11) is provided with an airbag module (24). The base frame (11) has a front member (20) that receives the load of an occupant, and a rear member (21) that is coupled to the front member (20) and together with the same forms a closed cross-sectional structure (P). The movable frame (12) is coupled to the front member (20), and the airbag module (24) is coupled to the rear member (21).

Description

Vehicle seats

[0001] The present invention relates to a vehicle seat, and more particularly to a vehicle seat in which an upper portion of a seat back frame can be tilted in the front-rear direction relative to a lower portion thereof.

[0002] Patent Document 1 discloses a vehicle seat having a seatback frame composed of a front frame and a rear frame. The front frame is positioned to receive the load of an occupant, and the rear frame is disposed opposite the front frame at a distance. The peripheral edges of the front frame and the rear frame are at least partially overlapped to form an overlapping portion, and are fixedly joined at a position away from the side receiving the load of the occupant. This gives the seatback frame a hollow, closed cross-sectional structure. A side airbag unit is joined to the side of the front frame.

[0003] Patent Document 2 discloses a vehicle seat including a seat back frame and a movable frame connected to the seat back frame so as to be tiltable. The seat back frame of Patent Document 2 includes a first side frame having an open cross-sectional structure, a second side frame having a closed cross-sectional structure, and a reinforcing member that closes the open cross-sectional structure of the first side frame.

[0004] JP 2011-201456 A JP 2017-094872 A

[0005] To improve both the comfort and safety of a vehicle seat, it is possible to provide a seat back frame with a movable frame and an airbag module. In this case, it is necessary to position the airbag module so that the movable frame does not hinder the deployment of the airbag.

[0006] In view of the above background, an object of the present invention is to provide a vehicle seat that includes a seat back whose upper portion is tiltable relative to the lower portion and that can deploy an airbag effectively.

[0007] In order to solve the above-mentioned problems, one aspect of the present invention is a vehicle seat (1), in which a seat back frame (10) that forms the skeleton of a seat back (5) has a base frame (11) and a movable frame (12) that is rotatably connected to the base frame, an airbag module (24) is provided on the base frame, the base frame has a front member (20) that receives the load of an occupant, and a rear member (21) that is connected to the front member and cooperates with the front member to form a closed cross-sectional structure (P), the movable frame is connected to the front member, and the airbag module is connected to the rear member.

[0008] According to this aspect, the movable frame and the airbag module can be more easily spaced apart than when they are provided on the same member, thereby providing a vehicle seat with improved safety and allowing the airbag to be deployed smoothly.

[0009] In the above aspect, preferably, the movable frame is connected at a front joint (58) of the front member, and the airbag module is connected at a rear joint (32) of the rear member, and the front joint is located above the rear joint.

[0010] According to this aspect, the movable frame and the airbag module are joined at positions spaced apart in the vertical direction, so that the deployment of the airbag is less likely to be hindered by the movable frame.

[0011] In the above aspect, preferably, the movable frame is connected to the front joint via a bracket (40), and the bracket is located above the rear joint.

[0012] According to this aspect, the movable frame and the airbag module are disposed at positions spaced apart in the up-down direction, so that the deployment of the airbag is less likely to be hindered by the movable frame.

[0013] In the above aspect, preferably, the front joint portions are provided in front of and behind the rear joint portion.

[0014] According to this aspect, the movable frame can be firmly connected to the front frame.

[0015] In the above aspect, preferably, the bracket has a plate portion (45A) arranged along the seat inner side surface of the front member, and a bulge portion (45B) that bulges toward the seat inner side and is spaced apart from the seat inner side surface of the front member, and the movable frame is rotatably connected to the seat inner side surface of the bulge portion.

[0016] According to this aspect, the movable frame can be easily rotatably coupled to the bracket.

[0017] In the above aspect, preferably, the base frame includes a pair of base side members (14) extending in the vertical direction, a pressure-receiving member (73) supported via an erection member is provided between the base side members, and the bracket has an attachment portion (82) for attaching one end of the erection member.

[0018] According to this aspect, there is no need to provide a separate member for joining the installation member to the base frame, so the number of parts of the vehicle seat can be reduced.

[0019] In the above aspect, preferably, the front coupling portions are provided in front of and behind the mounting portion.

[0020] According to this aspect, the installation member can be firmly connected to the front frame.

[0021] In the above aspect, preferably, the mounting portion has a plate-shaped flange portion (60) having a surface facing in the vertical direction, and a through hole (62) provided in the flange portion and through which the installation member is inserted.

[0022] According to this aspect, the installation member can be connected to the bracket by a simple method.

[0023] In the above aspect, preferably, the airbag module constitutes an outer airbag module (24L) connected to the outer side of the base frame, and an inner airbag module (24R) including a near-side airbag is further provided on the inner side of the base frame, and the bracket is positioned between the outer airbag module and the inner airbag module.

[0024] According to this aspect, the inner airbag module and the outer airbag module are disposed on the left and right sides of the movable frame, thereby enabling the inner airbag module and the outer airbag module to be disposed so as to be able to deploy to the sides of the seated occupant, thereby improving the safety of the vehicle seat.

[0025] Vehicle seats equipped with a seat back whose upper portion can be tilted forward and backward relative to the lower portion, i.e., a so-called center-folding seat back, are known. By tilting the upper portion of the seat back relative to the lower portion, the shape of the seat back can be made to fit the physique of the seated person, which has the advantage of improving the comfort of the vehicle seat.

[0026] Japanese Patent Application Laid-Open Publication No. 2016-088255 discloses a vehicle seat equipped with such a folding seatback. The vehicle seat is configured by a seatback frame that forms the framework of the seatback, and a pressure-receiving member for supporting the occupant's back is attached to the seatback frame. The seatback frame is composed of a lower frame that constitutes the lower part of the seatback frame and an upper frame that constitutes the upper part of the seatback frame. The upper frame is rotatably connected to the upper part of the lower frame via a shaft member extending in the left-right direction. A drive unit that swings the upper frame is attached to the lower frame. The drive force exerted by the drive unit causes the upper frame to tilt in the front-rear direction relative to the upper part of the lower frame.

[0027] The pressure-receiving member is disposed within the seatback frame from the position corresponding to the occupant's shoulders to the position corresponding to the occupant's waist. The upper part of the pressure-receiving member is connected to the upper seatback frame via a first wire, and the pressure-receiving member from the center to the lower part is connected to the lower seatback frame via a second wire.

[0028] In the vehicle seat disclosed in JP 2016-088255 A, the pressure-receiving member is connected to both the upper seatback frame and the lower seatback frame. Therefore, when the upper seatback frame tilts relative to the lower seatback frame, the pressure-receiving member must also deform in accordance with the tilt. Meanwhile, the pressure-receiving member must be hard enough to support the occupant. Therefore, the deformation of the pressure-receiving member may not adequately follow the tilt of the upper seatback frame, which could reduce the comfort of the vehicle seat.

[0029] Therefore, in a vehicle seat having a seat back in which the upper portion can be tilted relative to the lower portion and which is equipped with a pressure-receiving member, it is an issue to make it easier for the pressure-receiving member to follow the tilting of the upper portion.

[0030] One aspect for solving the above problem is a vehicle seat (1), in which a seat back frame (10) constituting a seat back (5) includes a base frame (11), a movable frame (12) tiltable relative to the base frame, and a pressure-receiving member (72) that supports the weight of a seated occupant, and the pressure-receiving member includes a lower pressure-receiving member (73) provided on the base frame and an upper pressure-receiving member (74) provided on the movable frame.

[0031] According to this aspect, the pressure-receiving member is composed of a lower pressure-receiving member provided on the base frame and an upper pressure-receiving member provided on the movable frame, so that the upper pressure-receiving member can be made to follow the tilt of the movable frame, making it easier for the pressure-receiving member to follow the tilt of the upper part of the seat back.

[0032] In the above aspect, preferably, the base frame comprises a pair of base side members (14) spaced apart from each other on the left and right, the movable frame includes a pair of left and right movable side members (38) rotatably connected to each of the base side members around a rotation axis (X) extending left and right, and the lower pressure-receiving member is supported by each of the base side members, and the upper pressure-receiving member is supported by each of the movable side members.

[0033] According to this aspect, the upper pressure-receiving member and the lower pressure-receiving member can be supported by the movable frame and the base frame, respectively.

[0034] In the above aspect, preferably, the upper pressure-receiving member is displaceable relative to the base frame, and the lower pressure-receiving member is displaceable relative to the movable frame.

[0035] According to this aspect, the upper pressure-receiving member constituting the upper part of the pressure-receiving member is configured to displace only in response to displacement of the movable frame, and the lower pressure-receiving member constituting the lower part of the pressure-receiving member is configured to displace only in response to displacement of the base frame. Therefore, for example, the influence of displacement of the movable frame on the lower part of the pressure-receiving member is reduced, making it easier for the pressure-receiving member to follow the tilt of the upper part.

[0036] In the above aspect, preferably, the lower pressure-receiving member is connected to the base frame via a lower installation member (79), and the upper pressure-receiving member is connected to the lower installation member so as to be tiltable in the front-to-rear direction.

[0037] According to this aspect, it is possible to improve the positional stability of the upper pressure-receiving member while reducing the influence of tilting of the movable frame.

[0038] In the above aspect, preferably, a mounting member (40) for rotatably connecting the movable frame is fixed to the base frame, and the lower installation member is connected to the base frame via the mounting member.

[0039] According to this aspect, the member for connecting the movable frame and the base frame and the member for attaching the lower installation member to the base frame can be constructed from a single mounting member, thereby reducing the number of parts in the vehicle seat.

[0040] In the above aspect, preferably, the mounting member is provided with a plate-shaped flange portion (91) having a surface facing in the vertical direction, and one end of the lower installation member is connected to the flange portion.

[0041] According to this aspect, the rigidity of the portion of the mounting member to which the lower installation member is attached can be increased.

[0042] In the above aspect, preferably, the lower pressure-receiving member has a lower main part (76) having a surface facing in the front-to-back direction, and when viewed in a direction along the front surface of the lower main part, the lower installation member and the upper pressure-receiving member are connected behind the lower main part.

[0043] According to this aspect, it is possible to prevent the seated occupant from feeling a foreign body sensation due to the connecting portion between the lower bridging member and the upper pressure-receiving member.

[0044] In the above aspect, preferably, the upper pressure-receiving member has an upper main part (84) having a surface facing in the front-to-back direction, and when viewed in a direction along the front surface of the upper main part, the lower installation member and the upper pressure-receiving member are connected behind the upper main part.

[0045] According to this aspect, it is possible to prevent the seated occupant from feeling a foreign body sensation due to the connecting portion between the lower bridging member and the upper pressure-receiving member.

[0046] Japanese Patent Application Laid-Open Publication No. 2009-226982 discloses a vehicle seat device equipped with a seat back tilting mechanism drive device that tilts the upper part of the seat back relative to the lower part of the seat back. The vehicle seat device in Patent Application Laid-Open Publication No. 2009-226982 includes a pair of left and right side frames that form the framework of the lower part of the seat back, and a motor supported by the side frames. The motor generates a driving force to tilt the upper part of the seat back relative to the lower part of the seat back.

[0047] Japanese Patent Laid-Open Publication No. 7-75608 discloses a vehicle seat having a shoulder support mechanism that adjusts the inclination of the upper part of the seat back relative to the lower part of the seat back. The vehicle seat of Patent Literature 2 includes a rectangular lower frame and a U-shaped upper frame. The lower ends of the upper frame are rotatably attached to the upper sides of the lower frame. A motor for the shoulder support mechanism that adjusts the inclination of the upper part of the seat back is fixed to approximately the center of the upper part of the lower frame.

[0048] Vehicle seats with folding seatbacks are sometimes equipped with an actuator that displaces the upper part of the seatback relative to the lower part. However, installing an actuator can lead to an increase in the size of the seat. Therefore, there has been a need to develop a structure that allows for compact placement of an actuator that tilts the upper part of the seatback relative to the lower part in vehicle seats with folding seatbacks.

[0049] Therefore, in a vehicle seat in which the upper part of the seat back can be tilted relative to the lower part, it is necessary to compactly arrange an actuator for tilting the lower part relative to the upper part.

[0050] One aspect for solving the above problem is a vehicle seat (1) in which the upper part of the seat back (5) can be tilted relative to the lower part, wherein the seat back frame (10) has a base frame (11), a movable frame (12) tiltably connected to the base frame, one end connected to the base frame, and the other end connected to the movable frame, and an actuator (98) that moves the one end and the other end toward and away from each other, and at least one of the base frame and the movable frame has a receiving recess (105) that receives at least a part of the actuator.

[0051] According to this aspect, at least a portion of the actuator is received in the receiving recess, which allows the actuator for tilting to be compactly arranged in a vehicle seat having a seat back whose upper portion is tiltable relative to its lower portion.

[0052] In the above aspect, preferably, the base frame comprises a pair of left and right base side members (14) and a base upper member (15) connecting the upper parts of the base side members, and the movable frame has a pair of left and right movable side members (38) each tiltably connected to the base side members and a movable upper member (39) connecting the upper parts of the movable side members, one end of which is connected to the base upper member and the other end of which is connected to the movable upper member.

[0053] According to this aspect, the actuator can be disposed at a position where the movable frame rotates relative to the base frame when driven by the actuator.

[0054] In the above aspect, preferably, the movable side member and the corresponding base side member, the one end of the actuator and the base upper member, and the other end of the actuator and the movable upper member are each rotatably connected about an axis (X, Y, Z) extending in the left-right direction.

[0055] According to this aspect, the actuator can be connected to the movable frame and the base frame so that the movable frame rotates relative to the base frame when driven by the actuator.

[0056] In the above aspect, the receiving recess is preferably provided on the front surface of the base upper member.

[0057] According to this aspect, the receiving recess can be provided at a position where the actuator can be easily accommodated.

[0058] In the above aspect, preferably, the receiving recess is recessed in the base upper member in a direction away from the movable upper member.

[0059] According to this aspect, the receiving recess can be provided at a position where the actuator can be easily accommodated.

[0060] In the above aspect, preferably, the actuator has a motor (98A), a gearbox (98C) connected to the output shaft of the motor, and a lead screw (98B) that slides relative to the gearbox when driven by the motor, the gearbox being rotatably connected to the base upper member, and the end of the lead screw being rotatably connected to the movable upper member.

[0061] According to this aspect, the actuator can be connected to the movable frame and the base frame so that the movable frame rotates relative to the base frame when driven by the actuator.

[0062] In the above aspect, preferably, the axial direction of the output shaft of the motor and the axial direction of the lead screw are perpendicular to each other, and the lead screw is provided in the receiving recess at a position offset to either the left or right.

[0063] According to this aspect, a space capable of accommodating the motor can be secured.

[0064] In the above aspect, preferably, a headrest frame (64) is coupled to the movable frame, and at least a portion of the actuator is located behind the headrest frame.

[0065] According to this aspect, the actuator can be disposed further rearward than when the actuator is disposed in front of the headrest frame, thereby preventing the actuator from causing a foreign body sensation to the seat occupant.

[0066] Japanese Patent Application Laid-Open Publication No. 2017-094872 discloses a vehicle seat including a seat back frame and a folding frame connected to the seat back frame so as to be tiltable. The folding frame has a pair of headrest mounting portions on the front surface for supporting a headrest.

[0067] In the vehicle seat described in JP 2017-094872 A, the headrest attachment portion is connected to the front surface of the folding frame and protrudes forward from the front surface of the folding frame, which may cause the seat occupant to feel a foreign body sensation due to the headrest attachment portion or the legs of the headrest frame.

[0068] Therefore, the challenge is to provide a vehicle seat that has a base frame and a movable frame that can be tilted relative to the base frame, and that can connect a headrest frame to the movable frame while preventing the occupant from feeling like there is a foreign body.

[0069] One aspect for solving the above problem is a vehicle seat (1), in which a seat back frame (5) constituting the skeleton of a seat back (5) has a base frame (11) and a movable frame (12) rotatably connected to the base frame about a rotation axis extending left and right, the base frame having a pair of base side members (14) extending in the vertical direction, the movable frame having a pair of left and right movable side members (38) rotatably connected to the base side members about a rotation axis (X) extending left and right, and a movable upper member (39) connecting the upper ends of the movable side members, a headrest frame supported by the movable frame, and the headrest frame is connected to the rear surface of the movable frame.

[0070] According to this aspect, the headrest frame is connected to the rear surface of the movable frame, and the portion of the headrest frame connected to the movable frame does not protrude forward beyond the movable frame, making it possible to provide a vehicle seat that allows the headrest frame to be connected to the movable frame while preventing the seat occupant from feeling a foreign body sensation.

[0071] In the above aspect, preferably, each of the movable side members comprises a side portion (41) extending in the vertical direction, and a shoulder portion (42) extending from the upper end of the side portion at an angle upward toward the inside of the seat, bending upward at a bent portion and extending further upward, and the headrest frame comprises a pair of vertical portions (65) spaced apart on the left and right, and a horizontal portion (66) extending on the left and right and connecting the upper ends of the vertical portions, and the vertical portions are joined at their lower ends to the bent portion.

[0072] According to this aspect, the headrest frame can be connected to a highly rigid portion of the movable frame.

[0073] In the above aspect, preferably, the base frame includes a base upper member (15) extending in the left-right direction and connecting the upper ends of the base side members, and a recess (105) recessed rearward is formed on the front surface of the base upper member behind the vertical portion.

[0074] According to this aspect, a space for accommodating the functional component can be formed on the front surface of the base upper member.

[0075] In the above aspect, preferably, an actuator (98) is provided that rotates the movable frame relative to the base frame by moving the upper part of the base frame and the upper part of the movable frame closer to or farther away from each other, and the actuator connects the front surface of the base upper member and the part of the movable frame between the two bending portions.

[0076] According to this aspect, the connection portion between the actuator and the movable frame can be located closer to the center of the seat in the left-right direction, thereby allowing the actuator to rotate the movable frame stably.

[0077] In the above aspect, preferably, the vertical portion has a headrest side portion (68) that is connected to the bent portion and extends upward, and a headrest shoulder portion (69) that extends from the upper end of the headrest side portion toward the inside of the seat at an angle upward, bends upward at a headrest bent portion (70), and extends further upward, and the connection portion between the actuator and the movable frame is located between the headrest bent portions in a front view.

[0078] According to this aspect, the connection portion between the actuator and the movable frame can be located closer to the center of the seat in the left-right direction, thereby allowing the actuator to rotate the movable frame stably.

[0079] In the above aspect, preferably, the base side member is provided with a pivoting bracket (40) for rotatably connecting the movable side member, and when the upper part of the movable side member is rotated to its rearmost position, the shoulder portion is located behind the pivoting bracket in a top view.

[0080] According to this aspect, the position of the movable frame when tilted most rearward can be set to an appropriate position.

[0081] In the above aspect, preferably, a pressure-receiving member (74) is provided to support the back of the seated occupant, the pressure-receiving member being supported on each of the movable side members via a mounting member (87), the movable side members being provided with mounting members (90) for mounting the mounting member, and when the upper part of the movable side member is rotated to its rearmost position, the shoulder is located in front of the mounting member in a top view.

[0082] According to this aspect, the position of the movable frame when tilted most rearward can be set to an appropriate position.

[0083] Japanese Patent Application Laid-Open Publication No. 2009-226982 discloses a vehicle seat device equipped with a seat back tilting mechanism drive device that tilts the upper part of the seat back relative to the lower part of the seat back. The vehicle seat device in Patent Document 1 includes a pair of left and right side frames that form the framework of the lower part of the seat back, and a motor supported by the side frames. The motor generates a driving force to tilt the upper part of the seat back relative to the lower part of the seat back.

[0084] Japanese Patent Application Laid-Open Publication No. 2016-088255 discloses a vehicle seat in which a pressure-receiving member for supporting the back of an occupant is attached to a seatback frame that forms the framework of the seatback. The seatback frame of the vehicle seat disclosed in Patent Application Laid-Open Publication No. 2016-088255 comprises a lower frame that constitutes the lower part of the seatback frame and an upper frame that constitutes the upper part of the seatback frame. The upper frame is rotatably connected to the upper part of the lower frame via a shaft member extending in the left-right direction. A drive unit that swings the upper frame is attached to the lower frame. The drive force exerted by the drive unit causes the upper frame to tilt in the front-rear direction relative to the upper part of the lower frame.

[0085] As described in Japanese Patent Application Laid-Open No. 2009-226982 and Japanese Patent Application Laid-Open No. 2016-088255, a seat back may be provided with an actuator (also referred to as a drive device) that tilts the upper part of the seat back frame relative to the lower part. Although providing an actuator makes it easy to tilt the upper part of the seat back, the provision of the actuator may cause a seat occupant to feel a foreign body sensation.

[0086] Therefore, in a vehicle seat equipped with a seat back having a base frame, a movable frame tiltably connected to the base frame, and an actuator that moves the movable frame, the challenge is to prevent the actuator from giving the occupant a foreign body sensation.

[0087] One aspect for solving the above problem is a vehicle seat (1) having a seat back frame (10) that forms the skeleton of a seat back (5), the seat back frame having a base frame (11), a movable frame (12) connected to the base frame so as to be tiltable in the fore-and-aft direction, and an actuator (98) that tilts the movable frame relative to the base frame, the movable frame being provided with an upper pressure-receiving member (74) that supports the load from the seated occupant, and at least a portion of the actuator being located behind the upper pressure-receiving member.

[0088] According to this aspect, at least a portion of the actuator is positioned behind the upper pressure-receiving member, thereby preventing the actuator from causing a foreign body sensation to the occupant compared to when the entire actuator is positioned in front of the upper pressure-receiving member.

[0089] In the above aspect, preferably, the movable frame has a pair of left and right movable side members (38) connected to the base frame so as to be rotatable about a rotation axis (X) extending left and right, and a movable upper member (39) connecting the upper ends of the movable side members, and the actuator connects the upper part of the base frame to the movable upper member and moves the movable upper member toward and away from the upper part of the base frame at least in one of two ways.

[0090] According to this aspect, the actuator is connected to the upper part of the base frame and the movable upper member, which allows the movable frame to tilt more stably than, for example, when the actuator is connected to the upper part of the base frame and the movable side member.

[0091] In the above aspect, preferably, the movable side member comprises a side portion (41) extending upward from the base frame, and a shoulder portion (42) extending from the upper end of the side portion at an angle upward toward the inside of the seat, bending upward at a bend portion and extending further upward, and the upper pressure-receiving member has a plate-shaped upper main portion (84) having a surface facing in the fore-and-aft direction, and a plate-shaped upper portion (85) extending forward from the left and right side edges of the upper main portion toward the outside of the seat, and the upper portion and the shoulder portion are arranged in positions aligned in the vertical direction.

[0092] According to this aspect, the upper pressure-receiving member can be disposed so as to follow the back of the seated occupant.

[0093] In the above aspect, preferably, the upper pressure-receiving member is supported on the front side of an upper installation member (87) supported on the movable frame, and when the upper part of the movable frame is rotated to its rearmost position, the part connecting the upper installation member and the movable frame is located in front of the actuator.

[0094] According to this aspect, the connecting portion between the upper installation member and the movable frame is located in front of the actuator, and the upper pressure-receiving member is supported on the front side of the upper installation member, so that the upper pressure-receiving member that supports the load from the seated occupant is located in front of the actuator, which prevents the actuator from giving the seated occupant a foreign body sensation.

[0095] In the above aspect, preferably, a lower pressure-receiving member (73) is provided at the lower part of the base frame, positioned below the upper pressure-receiving member and supporting the load from the seated occupant, and the lower pressure-receiving member is supported on the front side of a lower installation member (79) supported on the base frame, and when the upper part of the movable frame rotates to its forwardmost position, the part where the lower installation member and the base frame are connected is located rearward of the front end of the actuator.

[0096] According to this aspect, the forward lean position can be set to an appropriate position.

[0097] In the above aspect, preferably, the base frame comprises a front member (20) that receives the load of the occupant, and a rear member (21) that is positioned at a distance opposite the front member and is connected to the front member at its edge, and the actuator is supported on the base frame at a position where the front member and the rear member face each other.

[0098] According to this aspect, the actuator can be supported at a position on the seat back frame where the rigidity is high.

[0099] In the above aspect, preferably, the base frame has a pair of base side members (14) arranged at a distance from each other on the left and right, and a base upper member (15) connecting the upper edges of the base side members, and the base upper member is provided with a bracket (103) connected to the base frame at a position where the front member and the rear member face each other, and the actuator is supported on the base frame via the bracket.

[0100] According to this aspect, the actuator can be supported at a highly rigid position on the seat back frame using a simple method.

[0101] In the above aspect, preferably, the base upper member is provided with a receiving recess (105) recessed rearward, and at least a portion of the actuator is received in the receiving recess.

[0102] According to this aspect, the actuator and the receiving recess are arranged at a position where they overlap in a side view, so that the actuator can be arranged compactly.

[0103] In the above aspect, preferably, the upper pressure-receiving member has a plate-shaped upper main portion (84) having a surface facing in the front-to-rear direction, and a plate-shaped upper portion (85) extending forward from the left and right side edges of the upper main portion toward the outside of the seat, and the movable frame is connected to the base frame so as to be rotatable around a rotation axis (X) extending left and right, and the upper main portion and the left and right upper portions are each located above the rotation axis when the upper part of the movable frame is rotated to its rearmost position.

[0104] According to this aspect, the upper pressure-receiving member can be supported by the movable frame so that the upper portion of the upper pressure-receiving member protrudes forward when the movable frame tilts forward.

[0105] In the above aspect, preferably, the lower edge of each of the upper portions is provided with a notch (95) cut out in the upward direction.

[0106] According to this aspect, the worker performing the assembly can easily visually recognize the connection portion between the movable frame and the seat back frame, thereby improving the workability of assembling the vehicle seat.

[0107] One aspect of the present invention is a vehicle seat (1), in which a seat back frame (10) that forms the skeleton of a seat back (5) has a base frame (11) and a movable frame (12) that is rotatably connected to the base frame, an airbag module (24) is provided on the base frame, the base frame has a front member (20) that receives the load of an occupant, and a rear member (21) that is connected to the front member and cooperates with the front member to form a closed cross-sectional structure (P), the movable frame is connected to the front member, and the airbag module is connected to the rear member.

[0108] According to this aspect, the movable frame and the airbag module can be more easily spaced apart than when they are provided on the same member, thereby providing a vehicle seat with improved safety and allowing the airbag to be deployed smoothly.

[0109] In the above aspect, preferably, the movable frame is connected at a front joint (58) of the front member, and the airbag module is connected at a rear joint (32) of the rear member, and the front joint is located above the rear joint.

[0110] According to this aspect, the movable frame and the airbag module are joined at positions spaced apart in the vertical direction, so that the deployment of the airbag is less likely to be hindered by the movable frame.

[0111] In the above aspect, preferably, the movable frame is connected to the front joint via a bracket (40), and the bracket is located above the rear joint.

[0112] According to this aspect, the movable frame and the airbag module are disposed at positions spaced apart in the up-down direction, so that the deployment of the airbag is less likely to be hindered by the movable frame.

[0113] In the above aspect, preferably, the front joint portions are provided in front of and behind the rear joint portion.

[0114] According to this aspect, the movable frame can be firmly connected to the front frame.

[0115] In the above aspect, preferably, the bracket has a plate portion (45A) arranged along the seat inner side surface of the front member, and a bulge portion (45B) that bulges toward the seat inner side and is spaced apart from the seat inner side surface of the front member, and the movable frame is rotatably connected to the seat inner side surface of the bulge portion.

[0116] According to this aspect, the movable frame can be easily rotatably coupled to the bracket.

[0117] In the above aspect, preferably, the base frame includes a pair of base side members (14) extending in the vertical direction, a pressure-receiving member (73) supported via an erection member is provided between the base side members, and the bracket has an attachment portion (82) for attaching one end of the erection member.

[0118] According to this aspect, there is no need to provide a separate member for joining the installation member to the base frame, so the number of parts of the vehicle seat can be reduced.

[0119] In the above aspect, preferably, the front coupling portions are provided in front of and behind the mounting portion.

[0120] According to this aspect, the installation member can be firmly connected to the front frame.

[0121] In the above aspect, preferably, the mounting portion has a plate-shaped flange portion (60) having a surface facing in the vertical direction, and a through hole (62) provided in the flange portion and through which the installation member is inserted.

[0122] According to this aspect, the installation member can be connected to the bracket by a simple method.

[0123] In the above aspect, preferably, the airbag module constitutes an outer airbag module (24L) connected to the outer side of the base frame, and an inner airbag module (24R) including a near-side airbag is further provided on the inner side of the base frame, and the bracket is positioned between the outer airbag module and the inner airbag module.

[0124] According to this aspect, the inner airbag module and the outer airbag module are disposed on the left and right sides of the movable frame, thereby enabling the inner airbag module and the outer airbag module to be disposed so as to be able to deploy to the sides of the seated occupant, thereby improving the safety of the vehicle seat.

[0125] In one embodiment, a vehicle seat (1) includes a seat back frame (10) constituting a seat back (5), which includes a base frame (11), a movable frame (12) tiltable relative to the base frame, and a pressure-receiving member (72) that supports the weight of a seated occupant, and the pressure-receiving member includes a lower pressure-receiving member (73) provided on the base frame and an upper pressure-receiving member (74) provided on the movable frame.

[0126] According to this aspect, the pressure-receiving member is composed of a lower pressure-receiving member provided on the base frame and an upper pressure-receiving member provided on the movable frame, so that the upper pressure-receiving member can be made to follow the tilt of the movable frame, making it easier for the pressure-receiving member to follow the tilt of the upper part of the seat back.

[0127] In the above aspect, preferably, the base frame comprises a pair of base side members (14) spaced apart from each other on the left and right, the movable frame includes a pair of left and right movable side members (38) rotatably connected to each of the base side members around a rotation axis (X) extending left and right, and the lower pressure-receiving member is supported by each of the base side members, and the upper pressure-receiving member is supported by each of the movable side members.

[0128] According to this aspect, the upper pressure-receiving member and the lower pressure-receiving member can be supported by the movable frame and the base frame, respectively.

[0129] In the above aspect, preferably, the upper pressure-receiving member is displaceable relative to the base frame, and the lower pressure-receiving member is displaceable relative to the movable frame.

[0130] According to this aspect, the upper pressure-receiving member constituting the upper part of the pressure-receiving member is configured to displace only in response to displacement of the movable frame, and the lower pressure-receiving member constituting the lower part of the pressure-receiving member is configured to displace only in response to displacement of the base frame. Therefore, for example, the influence of displacement of the movable frame on the lower part of the pressure-receiving member is reduced, making it easier for the pressure-receiving member to follow the tilt of the upper part.

[0131] In the above aspect, preferably, the lower pressure-receiving member is connected to the base frame via a lower installation member (79), and the upper pressure-receiving member is connected to the lower installation member so as to be tiltable in the front-to-rear direction.

[0132] According to this aspect, it is possible to improve the positional stability of the upper pressure-receiving member while reducing the influence of tilting of the movable frame.

[0133] In the above aspect, preferably, a mounting member (40) for rotatably connecting the movable frame is fixed to the base frame, and the lower installation member is connected to the base frame via the mounting member.

[0134] According to this aspect, the member for connecting the movable frame and the base frame and the member for attaching the lower installation member to the base frame can be constructed from a single mounting member, thereby reducing the number of parts in the vehicle seat.

[0135] In the above aspect, preferably, the mounting member is provided with a plate-shaped flange portion (91) having a surface facing in the vertical direction, and one end of the lower installation member is connected to the flange portion.

[0136] According to this aspect, the rigidity of the portion of the mounting member to which the lower installation member is attached can be increased.

[0137] In the above aspect, preferably, the lower pressure-receiving member has a lower main part (76) having a surface facing in the front-to-back direction, and when viewed in a direction along the front surface of the lower main part, the lower installation member and the upper pressure-receiving member are connected behind the lower main part.

[0138] According to this aspect, it is possible to prevent the seated occupant from feeling a foreign body sensation due to the connecting portion between the lower bridging member and the upper pressure-receiving member.

[0139] In the above aspect, preferably, the upper pressure-receiving member has an upper main part (84) having a surface facing in the front-to-back direction, and when viewed in a direction along the front surface of the upper main part, the lower installation member and the upper pressure-receiving member are connected behind the upper main part.

[0140] According to this aspect, it is possible to prevent the seated occupant from feeling a foreign body sensation due to the connecting portion between the lower bridging member and the upper pressure-receiving member.

[0141] One aspect is a vehicle seat (1) in which the upper part of the seat back (5) can be tilted relative to the lower part, wherein the seat back frame (10) has a base frame (11), a movable frame (12) tiltably connected to the base frame, one end connected to the base frame and the other end connected to the movable frame, and an actuator (98) that moves the one end and the other end toward and away from each other, and at least one of the base frame and the movable frame has a receiving recess (105) that receives at least a part of the actuator.

[0142] According to this aspect, at least a portion of the actuator is received in the receiving recess, which allows the actuator for tilting to be compactly arranged in a vehicle seat having a seat back whose upper portion is tiltable relative to its lower portion.

[0143] In the above aspect, preferably, the base frame comprises a pair of left and right base side members (14) and a base upper member (15) connecting the upper parts of the base side members, and the movable frame has a pair of left and right movable side members (38) each tiltably connected to the base side members and a movable upper member (39) connecting the upper parts of the movable side members, one end of which is connected to the base upper member and the other end of which is connected to the movable upper member.

[0144] According to this aspect, the actuator can be disposed at a position where the movable frame rotates relative to the base frame when driven by the actuator.

[0145] In the above aspect, preferably, the movable side member and the corresponding base side member, the one end of the actuator and the base upper member, and the other end of the actuator and the movable upper member are each rotatably connected about an axis (X, Y, Z) extending in the left-right direction.

[0146] According to this aspect, the actuator can be connected to the movable frame and the base frame so that the movable frame rotates relative to the base frame when driven by the actuator.

[0147] In the above aspect, the receiving recess is preferably provided on the front surface of the base upper member.

[0148] According to this aspect, the receiving recess can be provided at a position where the actuator can be easily accommodated.

[0149] In the above aspect, preferably, the receiving recess is recessed in the base upper member in a direction away from the movable upper member.

[0150] According to this aspect, the receiving recess can be provided at a position where the actuator can be easily accommodated.

[0151] In the above aspect, preferably, the actuator has a motor (98A), a gearbox (98C) connected to the output shaft of the motor, and a lead screw (98B) that slides relative to the gearbox when driven by the motor, the gearbox being rotatably connected to the base upper member, and the end of the lead screw being rotatably connected to the movable upper member.

[0152] According to this aspect, the actuator can be connected to the movable frame and the base frame so that the movable frame rotates relative to the base frame when driven by the actuator.

[0153] In the above aspect, preferably, the axial direction of the output shaft of the motor and the axial direction of the lead screw are perpendicular to each other, and the lead screw is provided in the receiving recess at a position offset to either the left or right.

[0154] According to this aspect, a space capable of accommodating the motor can be secured.

[0155] In the above aspect, preferably, a headrest frame (64) is coupled to the movable frame, and at least a portion of the actuator is located behind the headrest frame.

[0156] According to this aspect, the actuator can be disposed further rearward than when the actuator is disposed in front of the headrest frame, thereby preventing the actuator from causing a foreign body sensation to the seat occupant.

[0157] In one embodiment, a vehicle seat (1) includes a seat back frame (5) that forms the skeleton of a seat back (5), the seat back frame (5) having a base frame (11) and a movable frame (12) that is rotatably connected to the base frame about a rotation axis that extends left and right, the base frame having a pair of base side members (14) that extend in the vertical direction, the movable frame having a pair of left and right movable side members (38) that are rotatably connected to the base side members about a rotation axis (X) that extends left and right, and a movable upper member (39) that connects the upper ends of the movable side members, a headrest frame supported by the movable frame, and the headrest frame is connected to the rear surface of the movable frame.

[0158] According to this aspect, the headrest frame is connected to the rear surface of the movable frame, and the portion of the headrest frame connected to the movable frame does not protrude forward beyond the movable frame, making it possible to provide a vehicle seat that allows the headrest frame to be connected to the movable frame while preventing the seat occupant from feeling a foreign body sensation.

[0159] In the above aspect, preferably, each of the movable side members comprises a side portion (41) extending in the vertical direction, and a shoulder portion (42) extending from the upper end of the side portion at an angle upward toward the inside of the seat, bending upward at a bent portion and extending further upward, and the headrest frame comprises a pair of vertical portions (65) spaced apart on the left and right, and a horizontal portion (66) extending on the left and right and connecting the upper ends of the vertical portions, and the vertical portions are joined at their lower ends to the bent portion.

[0160] According to this aspect, the headrest frame can be connected to a highly rigid portion of the movable frame.

[0161] In the above aspect, preferably, the base frame includes a base upper member (15) extending in the left-right direction and connecting the upper ends of the base side members, and a recess (105) recessed rearward is formed on the front surface of the base upper member behind the vertical portion.

[0162] According to this aspect, a space for accommodating the functional component can be formed on the front surface of the base upper member.

[0163] In the above aspect, preferably, an actuator (98) is provided that rotates the movable frame relative to the base frame by moving the upper part of the base frame and the upper part of the movable frame closer to or farther away from each other, and the actuator connects the front surface of the base upper member and the part of the movable frame between the two bending portions.

[0164] According to this aspect, the connection portion between the actuator and the movable frame can be located closer to the center of the seat in the left-right direction, thereby allowing the actuator to rotate the movable frame stably.

[0165] In the above aspect, preferably, the vertical portion has a headrest side portion (68) that is connected to the bent portion and extends upward, and a headrest shoulder portion (69) that extends from the upper end of the headrest side portion toward the inside of the seat at an angle upward, bends upward at a headrest bent portion (70), and extends further upward, and the connection portion between the actuator and the movable frame is located between the headrest bent portions in a front view.

[0166] According to this aspect, the connection portion between the actuator and the movable frame can be located closer to the center of the seat in the left-right direction, thereby allowing the actuator to rotate the movable frame stably.

[0167] In the above aspect, preferably, the base side member is provided with a pivoting bracket (40) for rotatably connecting the movable side member, and when the upper part of the movable side member is rotated to its rearmost position, the shoulder portion is located behind the pivoting bracket in a top view.

[0168] According to this aspect, the position of the movable frame when tilted most rearward can be set to an appropriate position.

[0169] In the above aspect, preferably, a pressure-receiving member (74) is provided to support the back of the seated occupant, the pressure-receiving member being supported on each of the movable side members via a mounting member (87), the movable side members being provided with mounting members (90) for mounting the mounting member, and when the upper part of the movable side member is rotated to its rearmost position, the shoulder is located in front of the mounting member in a top view.

[0170] According to this aspect, the position of the movable frame when tilted most rearward can be set to an appropriate position.

[0171] One embodiment is a vehicle seat (1) having a seat back frame (10) that forms the skeleton of a seat back (5), the seat back frame having a base frame (11), a movable frame (12) connected to the base frame so as to be tiltable in the fore-and-aft direction, and an actuator (98) that tilts the movable frame relative to the base frame, the movable frame being provided with an upper pressure-receiving member (74) that supports the load from the seated occupant, and at least a portion of the actuator being located behind the upper pressure-receiving member.

[0172] According to this aspect, at least a portion of the actuator is positioned behind the upper pressure-receiving member, thereby preventing the actuator from causing a foreign body sensation to the occupant compared to when the entire actuator is positioned in front of the upper pressure-receiving member.

[0173] In the above aspect, preferably, the movable frame has a pair of left and right movable side members (38) connected to the base frame so as to be rotatable about a rotation axis (X) extending left and right, and a movable upper member (39) connecting the upper ends of the movable side members, and the actuator connects the upper part of the base frame to the movable upper member and moves the movable upper member toward and away from the upper part of the base frame at least in one of two ways.

[0174] According to this aspect, the actuator is connected to the upper part of the base frame and the movable upper member, which allows the movable frame to tilt more stably than, for example, when the actuator is connected to the upper part of the base frame and the movable side member.

[0175] In the above aspect, preferably, the movable side member comprises a side portion (41) extending upward from the base frame, and a shoulder portion (42) extending from the upper end of the side portion at an angle upward toward the inside of the seat, bending upward at a bend portion and extending further upward, and the upper pressure-receiving member has a plate-shaped upper main portion (84) having a surface facing in the fore-and-aft direction, and a plate-shaped upper portion (85) extending forward from the left and right side edges of the upper main portion toward the outside of the seat, and the upper portion and the shoulder portion are arranged in positions aligned in the vertical direction.

[0176] According to this aspect, the upper pressure-receiving member can be disposed so as to follow the back of the seated occupant.

[0177] In the above aspect, preferably, the upper pressure-receiving member is supported on the front side of an upper installation member (87) supported on the movable frame, and when the upper part of the movable frame is rotated to its rearmost position, the part connecting the upper installation member and the movable frame is located in front of the actuator.

[0178] According to this aspect, the connecting portion between the upper installation member and the movable frame is located in front of the actuator, and the upper pressure-receiving member is supported on the front side of the upper installation member, so that the upper pressure-receiving member that supports the load from the seated occupant is located in front of the actuator, which prevents the actuator from giving the seated occupant a foreign body sensation.

[0179] In the above aspect, preferably, a lower pressure-receiving member (73) is provided at the lower part of the base frame, positioned below the upper pressure-receiving member and supporting the load from the seated occupant, and the lower pressure-receiving member is supported on the front side of a lower installation member (79) supported on the base frame, and when the upper part of the movable frame rotates to its forwardmost position, the part where the lower installation member and the base frame are connected is located rearward of the front end of the actuator.

[0180] According to this aspect, the forward lean position can be set to an appropriate position.

[0181] In the above aspect, preferably, the base frame comprises a front member (20) that receives the load of the occupant, and a rear member (21) that is positioned at a distance opposite the front member and is connected to the front member at its edge, and the actuator is supported on the base frame at a position where the front member and the rear member face each other.

[0182] According to this aspect, the actuator can be supported at a position on the seat back frame where the rigidity is high.

[0183] In the above aspect, preferably, the base frame has a pair of base side members (14) arranged at a distance from each other on the left and right, and a base upper member (15) connecting the upper edges of the base side members, and the base upper member is provided with a bracket (103) connected to the base frame at a position where the front member and the rear member face each other, and the actuator is supported on the base frame via the bracket.

[0184] According to this aspect, the actuator can be supported at a highly rigid position on the seat back frame using a simple method.

[0185] In the above aspect, preferably, the base upper member is provided with a receiving recess (105) recessed rearward, and at least a portion of the actuator is received in the receiving recess.

[0186] According to this aspect, the actuator and the receiving recess are arranged at a position where they overlap in a side view, so that the actuator can be arranged compactly.

[0187] In the above aspect, preferably, the upper pressure-receiving member has a plate-shaped upper main portion (84) having a surface facing in the front-to-rear direction, and a plate-shaped upper portion (85) extending forward from the left and right side edges of the upper main portion toward the outside of the seat, and the movable frame is connected to the base frame so as to be rotatable around a rotation axis (X) extending left and right, and the upper main portion and the left and right upper portions are each located above the rotation axis when the upper part of the movable frame is rotated to its rearmost position.

[0188] According to this aspect, the upper pressure-receiving member can be supported by the movable frame so that the upper portion of the upper pressure-receiving member protrudes forward when the movable frame tilts forward.

[0189] In the above aspect, preferably, the lower edge of each of the upper portions is provided with a notch (95) cut out in the upward direction.

[0190] According to this aspect, the worker performing the assembly can easily visually recognize the connection portion between the movable frame and the seat back frame, thereby improving the workability of assembling the vehicle seat.

[0191] A perspective view of a seat according to an embodiment. A perspective view of a seat back frame, a movable frame, and an airbag module when the movable part is in an upright position. (A) Front view and (B) rear view of the seat back frame and the airbag module. A side view of the seat back frame when the movable part is in an upright position. (A) Perspective view of the front panel and (B) Rear panel. Cross-sectional view taken along VI-VI in FIG. 2. A perspective view showing (A) a bead, (B) a first modified example of the bead, (C) a second modified example of the bead, and (D) a third modified example of the bead provided on the front panel. A perspective view of the seat back frame, the movable frame, and the airbag module when the movable part is in a forward tilted position. A perspective view of the frame and airbag module. A perspective view of the movable frame, upper installation member, lower installation member, and rotating bracket. A perspective view showing the joint portion of the rotating bracket and base frame, and the joint portion of the rotating bracket and movable frame. A side cross-sectional view taken along the line XI-XI of FIG. 2, showing an enlarged view of the peripheral portion of the rotating bracket. A top view of the seat back frame, movable frame, and airbag module when the movable part is in the upright position. A top view of the seat back frame, movable frame, and airbag module when the movable part is in the forward tilted position. A side view of the seat back frame when the movable part is in the forward tilted position.

[0192] Hereinafter, an embodiment of a vehicle seat according to the present invention will be described with reference to the drawings. In the following description, left and right are defined based on the position of an occupant seated in the seat.

[0193] Additionally, the direction toward the center of the seat in the left-right direction (also referred to as the seat width direction) when viewed from the front is referred to as the inward side of the seat (or the seat inner side), and the direction away from the center of the seat in the left-right direction is referred to as the outward side of the seat (or the seat outer side).

[0194] <Overall Structure of the Seat> As shown in FIG. 1 , a vehicle seat (hereinafter referred to as seat 1) is placed on a floor 3 that defines the bottom of a passenger compartment 2 (also referred to as the vehicle interior) of an automobile. The seat 1 has a seat cushion 4 provided on the floor 3, a seat back 5 extending upward from the rear of the seat cushion 4, and a headrest 6 provided on the upper part of the seat back 5. The seat cushion 4 forms a seating surface 4S and supports the buttocks of a seated occupant. The seat back 5 forms a backrest surface 5S facing forward and supports the back of the seated occupant. The headrest 6 is positioned behind the head of the seated occupant. The seat cushion 4 may be supported on the floor 3 via a sliding device (not shown) so as to be slidable back and forth.

[0195] The seat back 5 includes a base portion 8 that forms the lower half of the seat back surface 5S, and a movable portion 9 that forms the upper half of the seat back surface 5S. The movable portion 9 is connected to and supported by the base portion 8 so as to be rotatable about a rotation axis X (also called a pivot axis) that passes through the lower portion and extends in the left-right direction. This allows the upper half of the seat back surface 5S to be tilted relative to the lower half. In this embodiment, the headrest 6 is fixed to the upper portion of the movable portion 9.

[0196] The seat 1 is configured so that the upper half of the backrest surface 5S can be tilted relative to the lower half, and the center portion of the seat back 5 can be folded. For this reason, the seat back 5 of the seat 1 is also referred to as a center-folding seat back. Hereinafter, the position of the movable part 9 when the upper part of the movable part 9 is tilted all the way back will be referred to as the upright position (also referred to as the backward tilt position), and the position of the movable part 9 when the upper part of the movable part 9 is tilted all the way forward after rotating from the upright position around the rotation axis X will be referred to as the forward tilt position.

[0197] The seat cushion 4 includes a seat cushion frame (not shown) that forms a skeleton, a pad member (not shown) supported by the seat cushion frame, and a skin material (not shown) that covers at least a portion of the surface of the pad member. The pad member that constitutes the seat cushion 4 is formed from a resilient cushion material such as polyurethane foam, and the skin material that covers the pad member may be formed from genuine leather, synthetic leather, fabric, or the like. The seat cushion 4 is formed by covering the pad member and the skin material on the seat cushion frame.

[0198] The seat back 5 includes a seat back frame 10 that forms a framework, a pad member (not shown) supported by the seat back frame 10, and a skin material (not shown) that covers at least a portion of the surface of the pad member. To facilitate folding of the seat back 5, the pad member may be configured such that an upper half that constitutes the movable portion 9 and a lower half that constitutes the base portion 8 are separate bodies, or the upper half that constitutes the movable portion 9 and the lower half that constitutes the base portion 8 may be integrally formed. Similarly, the skin material may be configured such that an upper half that constitutes the movable portion 9 and a lower half that constitutes the base portion 8 are separate bodies.

[0199] Next, the seat back frame 10 will be described in detail.

[0200] 2, the seatback frame 10 has a base frame 11 that forms the framework of the base portion 8, and a movable frame 12 that forms the framework of the movable portion 9 and is connected to the base frame 11 so as to be tiltable (rotatable) about a rotation axis X. A reclining shaft 13 to which a seat cushion frame is connected is provided at the bottom of the base frame 11.

[0201] <Base Frame> As shown in Figures 2, 3(A), and 3(B), the base frame 11 is a rectangular frame including a pair of left and right base side members 14, a base upper member 15, and a base lower member 16. The base side members 14 each extend in the vertical direction and are spaced apart on the left and right. The base upper member 15 extends left and right and connects the upper portions (upper ends, in this embodiment) of the two base side members 14. The base lower member 16 also extends left and right and connects the lower portions of the two base side members 14. As a result, the base frame 11 has a rectangular frame shape when viewed from the front.

[0202] In this embodiment, as shown in FIG. 3B , the base frame 11 includes two base middle members 17 that connect the vertical center of the left base side member 14 with the vertical center of the right base side member 14. The two base middle members 17 are spaced apart vertically. Hereinafter, the upper base middle member 17 will be referred to as the upper middle member 17U, and the lower base middle member 17 will be referred to as the lower middle member 17D. The horizontal center of the upper middle member 17U and the horizontal center of the base upper member 15 are connected by a center member 18.

[0203] Each base side member 14 is provided with a plate-shaped side edge portion 19 that extends from its rear end toward the inside of the seat and has a surface facing forward. The front surface of the side edge portion 19 and the wall surface of the base side member 14 on the inside of the seat are connected at a substantially right angle in top view.

[0204] As shown in FIGS. 4, 5A, and 5B, the base frame 11 includes a front panel 20 (also called a front member or a front frame) and a rear panel 21 (also called a rear member or a rear frame).

[0205] As shown in Fig. 5(A), the front panel 20 is a rectangular frame made of bent sheet metal members. The front panel 20 constitutes the seat occupant side of the base frame 11 and bears the weight of the occupant. As shown in Fig. 5(B), the rear panel 21 is also a rectangular frame made of bent sheet metal members. The rear panel 21 is disposed opposite the front panel 20 and constitutes the side of the base frame 11 away from the seat occupant.

[0206] 6, the rear panel 21 has an outer frame portion 21A that forms the seat outer surface of the base side member 14, a first extension portion 21B that extends from the front edge of the outer frame portion 21A toward the inside of the seat, and a second extension portion 21C that extends from the rear edge of the outer frame portion 21A toward the inside of the seat. The front panel 20 has an inner frame portion 20A that forms the seat inner portion of the base side member 14, a third extension portion 20B that extends from the front edge of the inner frame portion 20A toward the outside of the seat, and a fourth extension portion 20C that extends from the front edge of the inner frame portion 20A toward the inside of the seat. The inner frame portion 20A and the outer frame portion 21A are opposed to each other and are arranged at positions spaced apart. The first extending portion 21B and the third extending portion 20B are overlapped, and the second extending portion 21C and the fourth extending portion 20C are overlapped and joined (welded in this embodiment), so that the rear panel 21 is joined to the front panel 20 at its edges. The rear panel 21 cooperates with the front panel 20 to form a closed cross-sectional structure P. As a result, a cavity 22 is formed in the base frame 11, making the base frame 11 hollow.

[0207] In this embodiment, the second extending portion 21C partially connects the left and right outer frame portions 21A, and the fourth extending portion 20C partially connects the inner frame portion 20A. The base middle member 17 is formed by overlapping and joining the second extending portion 21C and the fourth extending portion 20C. The central member 18 (more specifically, the vertical center portion of the central member 18) is mainly composed of the rear panel 21 only.

[0208] 3A and 3B, two airbag modules 24 are coupled to the base frame 11. One of the airbag modules 24 is coupled to the vehicle exterior side (left side in this embodiment) of the base frame 11 (base side member 14). As a result, the airbag module 24 coupled to the vehicle exterior side of the base frame 11 constitutes an outer airbag module 24L.

[0209] The other airbag module 24 is connected to the vehicle interior side (the right side in this embodiment) of the base frame 11 (base side member 14). As a result, the airbag module 24 connected to the vehicle interior side of the base frame 11 constitutes an inner airbag module 24R that includes a near-side airbag.

[0210] The outer airbag module 24L and the inner airbag module 24R are located on the left and right sides of the movable frame 12, respectively, and are connected to the side surfaces of the rear panel 21 on the seat outer side. This allows the airbag modules 24 to be mounted on both the left and right sides of the base frame 11 on the seat outer side. This allows the airbags 25 to be deployed on both sides of the seat outside the seat of the seat occupant, thereby improving the safety of the seat 1.

[0211] <Airbag Module, Bolt Holes, and Access Holes> As shown in Figure 6, the airbag module 24 includes an airbag 25, an inflator 26 that inflates the airbag 25 by introducing gas into the interior of the airbag 25, and a case 27 that houses the airbag 25 and the inflator 26. A retainer 28 is provided on the side of the airbag module 24 facing the seat interior. A plurality of stud bolts 29 are provided on the inflator 26. The stud bolts 29 pass through the retainer 28 and the bottom wall of the case 27 located on the seat interior, and protrude toward the seat interior.

[0212] 4 and 5B, the outer frame portion 21A of the rear panel 21 is provided with fastening holes 30 through which stud bolts 29 pass. The stud bolts 29 are inserted into the corresponding fastening holes 30 and fastened with nuts 31, thereby fastening the airbag module 24 to the seat-outside side surface of the base side member 14 (i.e., the seat-outside side surface of the rear panel 21). Hereinafter, the joint portion of the rear panel 21 with the outer airbag module 24L will be referred to as a rear joint portion 32. In this embodiment, the rear joint portion 32 is formed by the fastening holes 30.

[0213] As shown in FIGS. 2 and 5A, the front panel 20 is provided with an access hole 33, which is a through hole for accessing the fastening hole 30 from the inside of the seat.

[0214] 4, the access hole 33 is configured so that at least one of the front-to-rear width and the up-to-down width (preferably both) is larger than the fastening hole 30, and the area of ​​the opening of the access hole 33 is larger than the area of ​​the opening of the fastening hole 30. This allows an operator to easily pass the nuts 31 and tools through the access hole 33, thereby improving the workability of assembling the airbag module 24.

[0215] In this embodiment, each airbag module 24 is provided with two stud bolts 29. Furthermore, four fastening holes 30 are arranged vertically in a row in one base side member 14 so that the airbag module 24 can be assembled in two positions (hereinafter referred to as upper and lower positions). Hereinafter, the four fastening holes 30 will be referred to as a first fastening hole 30A, a second fastening hole 30B, a third fastening hole 30C, and a fourth fastening hole 30D, in order from top to bottom.

[0216] The airbag module 24 is assembled to the base side member 14 in an upper position by inserting and fastening the stud bolts 29 into the first fastening hole 30A and the third fastening hole 30C, respectively. On the other hand, the airbag module 24 is assembled to the base side member 14 in a lower position by inserting and fastening the stud bolts 29 into the second fastening hole 30B and the fourth fastening hole 30D, respectively.

[0217] Therefore, two access holes 33 are provided in the inner frame portion 20A of the front panel 20: an upper access hole 33A located on the seat inside of the first fastening hole 30A and the second fastening hole 30B, and a lower access hole 33B located on the seat inside of the third fastening hole 30C and the fourth fastening hole 30D. The upper access hole 33A and the lower access hole 33B are formed side by side in the front panel 20.

[0218] 4, the upper access hole 33A is formed to overlap the first fastening hole 30A and the second fastening hole 30B in a side view. The upper edge of the upper access hole 33A is located above the upper edge of the first fastening hole 30A, and the lower edge of the upper access hole 33A is located below the lower edge of the second fastening hole 30B.

[0219] The lower access hole 33B is formed to overlap the third fastening hole 30C and the fourth fastening hole 30D in a side view. The upper edge of the lower access hole 33B is located above the upper edge of the third fastening hole 30C, and the lower edge of the lower access hole 33B is located below the lower edge of the fourth fastening hole 30D.

[0220] 2 and 5A, beads 35 are provided in the vicinity of the access holes 33 of the front panel 20. The beads 35 function as rigidity enhancing portions that increase the rigidity of the portions of the front panel 20 near the access holes 33. In this embodiment, the beads 35 are provided rearward of the two access holes 33, at corners 36 that are connecting portions between the side edge portions 19 and the base side members 14 (inner frame portions 20A). The beads 35 form protruding ridges at the corners 36. The beads 35 may be formed by pushing (bending) the front panel 20 at the corners 36 in a direction that tilts forward toward the seat interior.

[0221] 7A shows an enlarged view of the vicinity of the bead 35 of the front panel 20. As shown in FIG. 7A, one bead 35 is provided at a corner 36 of the front panel 20 so as to extend in the vertical direction. The upper end of the bead 35 is located below the upper end of the upper access hole 33A. The lower end of the bead 35 is located below the lower end of the lower access hole 33B.

[0222] However, the number, shape, and arrangement of the beads 35 are not limited to the embodiment shown in Fig. 7(A). Figures 7(B) to (D) show modified examples of the number, shape, and arrangement of the beads 35.

[0223] 7B, one bead 35 is provided to extend vertically at the corner 36. The upper end of the bead 35 is located above the upper end of the upper access hole 33A. The lower end of the bead 35 is located below the lower end of the lower access hole 33B.

[0224] 7C, one bead 35 is provided at the corner 36 so as to extend in the vertical direction. The upper end of the bead 35 is located above the upper end of the upper access hole 33A. The lower end of the bead 35 is located above the lower end of the lower access hole 33B.

[0225] 7(D), multiple beads 35 are arranged vertically. The beads 35 may be arranged vertically at equal intervals. The upper end of the uppermost bead 35 is located above the upper access hole 33A. The lower end of the lowermost bead 35 is located below the lower access hole 33B.

[0226] 7A to 7D show beads 35 provided on the vehicle exterior side base side member 14, but beads 35 of corresponding shapes may also be provided on the vehicle interior side base side member 14. The beads 35 provided on the vehicle exterior side base side member 14 and the beads 35 provided on the vehicle interior side base side member 14 may have the same (bilaterally symmetrical) shape, or one may be formed to be longer than the other. In the example shown in FIG. 7D, the number of beads 35 provided on the vehicle exterior side base side member 14 may be different from the number of beads 35 provided on the vehicle interior side base side member 14.

[0227] 6, the front panel 20 may be joined to the rear panel 21 at a position that avoids the bead 35. This makes it possible to easily join the front panel 20 and the rear panel 21. Note that various known methods such as joining by laser welding or bolt fastening can be used to join the front panel 20 and the rear panel 21.

[0228] On the other hand, the front panel 20 may be joined to the rear panel 21 at a position overlapping the bead 35. This allows the front panel 20 to be joined to the rear panel 21 at a portion with high rigidity.

[0229] <Movable Frame> As shown in Figures 2, 8, and 9, the movable frame 12 includes a pair of left and right movable side members 38 and a movable upper member 39. The movable side members 38 are spaced apart from each other and extend in the vertical direction. The movable upper member 39 also extends in the horizontal direction and connects the upper portions of the two movable side members 38. The lower ends of each movable side member 38 are coupled to the base side member 14 via pivot brackets 40 (also referred to as mounting members) so as to be rotatable about the rotation axis X. As can be seen from Figures 2 and 9, the movable frame 12 is coupled to the base frame 11 so as to be rotatable (i.e., tiltable) about the rotation axis X.

[0230] In this embodiment, the movable frame 12 is made of a bent pipe material, but is not limited to this and may be made of one or more sheet metal members.

[0231] 9 , each movable side member 38 has a movable member side portion 41 constituting a lower portion and movable member shoulder portions 42 constituting a central and upper portion. Each movable member side portion 41 extends in the vertical direction. Each movable member side portion 41 is connected at its lower end to a base side member 14 on the seat inner side via a pivot bracket 40 so as to be rotatable about a rotation axis X. Each movable member shoulder portion 42 is connected to an upper end of the movable member side portion 41. The movable member shoulder portion 42 extends obliquely upward from the upper end of the movable member side portion 41 toward the seat inner side, then bends upward at a movable member bend portion 43, and continues to extend upward. The movable member shoulder 42 of the left movable side member 38 is connected at its upper end to the left end of the movable upper member 39, and the movable member shoulder 42 of the right movable side member 38 is connected at its upper end to the right end of the movable upper member 39.

[0232] 2, in this embodiment, auxiliary members 44 are provided on the movable frame 12 and connected to the left and right movable side members 38. The auxiliary members 44 are made of bent wires, and are connected to the corresponding movable side members 38 at both left and right ends.

[0233] As shown in FIG. 10 , the pivotal bracket 40 is fixed to the base frame 11 (more specifically, the base side member 14) and connects the movable frame 12 to the base frame 11 (the base side member 14) so ​​as to be pivotable (also referred to as rotatable) about the rotation axis X.

[0234] The pivoting bracket 40 is made of a bent sheet metal member and includes a pivoting bracket front portion 45 connected to the seat-inner side surface of one of the left and right base side members 14, and a pivoting bracket rear portion 46 extending inward from the rear edge of the pivoting bracket front portion 45 and connected to the front surface of the side edge portion 19.

[0235] The pivot bracket front portion 45 has a flat plate portion 45A and a bulging portion 45B that bulges inward toward the seat. The plate portion 45A is disposed along the seat-inner side surface of the front panel 20 that constitutes the base side member 14. The bulging portion 45B is circular in side view. The bulging portion 45B is spaced apart from the seat-inner side surface of the front panel 20 that constitutes the base side member 14. A through-hole 48 (see FIG. 9) is provided at the lower end of each of the movable side members 38. A pin 49 (see FIG. 10) that passes through the through-hole 48 and extends in the left-right direction is fixed to the bulging portion 45B. This connects the movable side member 38 to the pin 49 for rotation about the rotation axis X. This connects the movable side member 38 to the seat-inner side surface of the bulging portion 45B for rotation about the rotation axis X.

[0236] 9, the pivot bracket front portion 45 and the pivot bracket rear portion 46 each have a bolt hole 50. Hereinafter, the bolt hole 50 provided in the pivot bracket front portion 45 will be referred to as a front bolt hole 50A, and the bolt hole 50 provided in the pivot bracket rear portion 46 will be referred to as a rear bolt hole 50B.

[0237] A stud bolt 52 protruding toward the inside of the seat is provided in a wall of the base side member 14 of the front panel 20 that forms the seat inner side. As shown in FIGS. 5A and 5B , in this embodiment, a first through hole 53 penetrating the wall is provided in the wall that forms the seat inner side of the base side member 14 of the front panel 20. The stud bolt 52 is inserted into the first through hole 53 and fixed to the front panel 20. A second through hole 54 penetrating in the plate thickness direction (front-to-rear direction) is provided in a portion of the side edge portion 19 that is located on the seat inner side of the first through hole 53. In this embodiment, the second through hole 54 penetrates both the front panel 20 and the rear panel 21. However, the second through hole 54 may be configured to penetrate only the front panel 20.

[0238] A stud bolt 52 is inserted into the front bolt hole 50A and the first through-hole 53, and a nut 55 is fastened to the stud bolt 52, thereby fastening the pivot bracket front portion 45 to the side surface on the seat inside of the base side member 14. A bolt 56 is inserted into the rear bolt hole 50B and the second through-hole 54, and a nut 57 is fastened to the front surface of the side edge 19. In this way, the pivot bracket 40 is fastened and fixed to the inner surface on the seat inside of the front panel 20 and to the side edge 19.

[0239] Hereinafter, the first through-hole 53 and the second through-hole 54, which are the connecting portions of the front panel 20 with the pivoting bracket 40, will be collectively referred to as a front connecting portion 58. The pivoting bracket 40 is fastened to the front connecting portion 58 of the front panel 20, and the movable frame 12 is rotatably connected to the front connecting portion 58 via the pivoting bracket 40. The front panel 20 is provided with two front connecting portions 58.

[0240] As shown in Fig. 2, the pivoting bracket 40 is located between the outer airbag module 24L and the inner airbag module 24R. The pivoting bracket 40 is located above the rear joint portion 32. As a result, the two front joint portions 58, which are joint portions between the front panel 20 and the movable frame 12, are both located above the rear joint portion 32. As shown in Fig. 10, the front joint portions 58 are provided in front of and behind the rear joint portion 32. Because the pivoting bracket 40 is joined to the front panel 20 at the front and rear of the rear joint portion 32, the movable frame 12 can be firmly joined to the front panel 20.

[0241] As shown in Figures 9 and 10, the pivoting bracket 40 has a flange portion 60. The flange portion 60 is plate-shaped and extends forward from the lower edge of the pivoting bracket rear portion 46. The flange portion 60 is rectangular with a surface facing in the up-down direction. As shown in Figure 10, the flange portion 60 has an insertion hole 62 that penetrates in the up-down direction at approximately the center in the front-rear and left-right directions. In this embodiment, the insertion hole 62 is circular in top view.

[0242] 9, the flange portion 60 is located between the two front joining portions 58 in the front-rear direction. That is, the front joining portions 58 are located in front of and behind the flange portion 60.

[0243] 2, a headrest frame 64 is coupled to the rear surface of the movable frame 12. The headrest frame 64 is a frame for supporting or configuring the headrest 6, and is provided to support the headrest 6 in this embodiment.

[0244] 2 and 3A, the headrest frame 64 includes a pair of left and right vertical portions 65 spaced apart from each other, and horizontal portions 66 extending left and right to connect the upper edges of the vertical portions 65. The vertical portions 65 are each joined at their lower ends to the movable member bent portions 43. This fixes the headrest frame 64 to the movable side member 38.

[0245] Each vertical portion 65 has a headrest side portion 68 and a headrest shoulder portion 69. The headrest side portion 68 is connected at its end to the movable side member 38 and extends upward. The headrest side portion 68 may be connected (welded) to the movable member bent portion 43. The headrest shoulder portion 69 is connected at its end to the upper end of the headrest side portion 68. The headrest shoulder portion 69 extends inclined upward from the upper end of the headrest side portion 68 toward the inside of the seat, bends upward at a headrest bent portion 70, and continues extending upward.

[0246] In this embodiment, the headrest frame 64 is made of a bent pipe material, but is not limited to this and may be made of one or more sheet metal members.

[0247] The headrest 6 is fixed to the upper part of the headrest frame 64. The headrest 6 may be composed of a plate-like member (not shown) facing the front-rear direction, a pad member (not shown) provided on the front surface of the plate-like member, and a skin material (not shown) covering the front surface of the pad member. The rear surface of the plate-like member may be fixed to the headrest frame 64, thereby connecting the headrest 6 to the upper front surface of the headrest frame 64.

[0248] 2, the seat back frame 10 is provided with a pressure receiving member 72 that supports the weight of a seated occupant. The pressure receiving member 72 includes a lower pressure receiving member 73 provided on the base frame 11 and an upper pressure receiving member 74 provided on the movable frame 12. The lower pressure receiving member 73 is supported by the base frame 11, and the upper pressure receiving member 74 is mainly supported by the movable frame 12. The upper pressure receiving member 74 is disposed above the lower pressure receiving member 73 in a front view.

[0249] <Lower Pressure-Receiving Member> The lower pressure-receiving member 73 is disposed behind the lower half of the back of the seated occupant and supports the weight of the lower half of the back of the seated occupant. As shown in Fig. 2, the lower pressure-receiving member 73 is made of a flat plate-like member. The lower pressure-receiving member 73 may be made of a resin plate-like member, or may be made of a metal plate material or the like.

[0250] As shown in Figure 3(A), the lower pressure-receiving member 73 includes a lower main portion 76 having a front surface facing the front-rear direction, and a pair of left and right lower portions 77 provided on the left and right edges of the lower main portion 76. The lower main portion 76 has a rectangular shape extending in the up-down direction in a front view. The lower portions 77 are each connected to the edge of the lower main portion 76 on the outer side of the seat. The lower portions 77 have a rectangular shape with a triangular notch cut out at the upper end on the outer side of the seat.

[0251] 2 and 3A, the lower pressure-receiving member 73 is disposed between the left base side member 14 and the right base side member 14. The lower pressure-receiving member 73 is supported by the left base side member 14 and the right base side member 14 via a lower installation member 79.

[0252] The lower installation member 79 is made of a bent metal rod-shaped member (a round bar in this embodiment). The lower installation member 79 may also be made of a metal pipe material.

[0253] As shown in FIG. 9 , the lower installation member 79 has a pair of left and right hooking portions 80 and a connecting portion 81 extending in the left-right direction and connecting the lower ends of the hooking portions 80. The hooking portion 80 has an outer vertical portion 80A extending upward from the outer end of the connecting portion 81, a lower horizontal portion 80B extending from the outer vertical portion 80A toward the inside of the seat, an inner vertical portion 80C extending upward from the inner end of the lower horizontal portion 80B, and an upper horizontal portion 80D extending outward from the inner vertical portion 80C. The outer ends of the upper horizontal portions 80D each have a downward extension toward the outside of the seat, a bent end, and a downwardly extending retaining portion 80E. As shown in FIG. 2 , the connecting portions 81 are provided with hooks 81A that are hooked and fixed in appropriate positions on the base lower member 16. This connects the connecting portions 81 to the base lower member 16 (see FIG. 2 ).

[0254] 9 , the retaining portion 80E of the lower installation member 79 is inserted into the insertion hole 62 of the flange portion 60. That is, one end of the lower installation member 79 is prevented from falling out of the insertion hole 62, and one end of the lower installation member 79 is coupled to the flange portion 60. This allows the lower installation member 79 to be coupled to the pivot bracket 40 in a simple manner. The flange portion 60 and the insertion hole 62 provided in the flange portion 60 form an attachment portion 82 for attaching one end of the lower installation member 79.

[0255] In this way, the member for connecting the movable frame 12 and the base frame 11 and the member for attaching the lower installation member 79 to the base frame 11 can be constructed from a single pivot bracket 40 (attachment member), so the number of parts in the seat 1 can be reduced without having to provide a separate member for joining the lower installation member 79 to the base frame 11.

[0256] Furthermore, one end of the lower installation member 79 is connected to the flange portion 60 of the pivot bracket 40. Therefore, the rigidity of the portion of the pivot bracket 40 to which the lower installation member 79 is attached can be increased.

[0257] Furthermore, the front connecting portions 58 are provided respectively in front and behind the mounting portion 82. Therefore, compared to when the front connecting portions 58 are provided only on one side, either the front or rear, the pivot bracket 40 can be more firmly connected to the front panel 20, and the lower installation member 79 can be stably supported by the front panel 20.

[0258] A plurality of hooks (not shown) are provided on the rear surface of the lower pressure-receiving member 73 and are hooked onto the lower installation member 79. The lower pressure-receiving member 73 is connected to the lower installation member 79 by the hooks being hooked onto the lower installation member 79. As a result, the lower pressure-receiving member 73 is connected to each of the base side members 14 via the lower installation member 79.

[0259] <Upper Pressure-Receiving Member> The upper pressure-receiving member 74 is disposed behind the upper part of the back of the seated occupant and supports the load on the upper part of the back of the seated occupant. As shown in Fig. 2, the upper pressure-receiving member 74 is made of a plate-like member, similar to the lower pressure-receiving member 73. The upper pressure-receiving member 74 may be made of a resin plate-like member, or may be made of a metal plate material or the like.

[0260] As shown in Fig. 3A, the upper pressure-receiving member 74 includes a flat upper main portion 84 having a front surface facing the front-rear direction, and a pair of left and right upper portions 85 provided on the left and right edges of the upper main portion 84. As shown in Fig. 2, the upper portions 85 are each flat, connected to the edge portions of the upper main portion 84 on the outer side of the seat (i.e., the left and right side edges), and extend forward toward the outside of the seat. This allows the upper pressure-receiving member 74 to be shaped to fit along the back of the seated occupant.

[0261] As shown in FIGS. 2 and 3A, each of the movable side members 38 is provided with an upper installation member 87 for connecting the upper pressure-receiving member 74 to the movable side member 38 .

[0262] 9, the upper installation member 87 is composed of a pair of left and right side frames 88. The side frames 88 are composed of bent metal rod-shaped members (round bars in this embodiment). The side frames 88 may also be composed of metal pipe material.

[0263] The side frame 88 has an upper vertical portion 88A extending in the vertical direction, an inclined portion 88B sloping downward from the lower end of the upper vertical portion 88A toward the inside of the seat, a lower vertical portion 88C extending downward from the lower end of the inclined portion 88B, and a lower horizontal portion 88D extending from the lower end of the lower vertical portion 88C toward the outside of the seat.

[0264] Each movable side member 38 is provided with a mounting bracket 90 for mounting the upper installation member 87 .

[0265] The mounting bracket 90 is fixed to the center of the movable side member 38, more specifically, to the upper part of the movable member side portion 41. In this embodiment, the mounting bracket 90 is made of a bent sheet metal member, and is fixed to the upper part of the movable member side portion 41 by welding.

[0266] The mounting bracket 90 has a flange portion 91, similar to the lower installation member 79. The flange portion 91 is plate-shaped with a main surface facing in the vertical direction. The flange portion 91 has a mounting hole 92 that penetrates in the vertical direction. The upper end of the upper vertical portion 88A of the upper installation member 87 is inserted into the mounting hole 92. In this way, the upper installation member 87 is attached to the movable side member 38 via the mounting bracket 90. In other words, the mounting bracket 90 forms a part that connects the upper installation member 87 and the movable frame 12.

[0267] The upper edge of the upper vertical portion 88A is provided with a horizontally bent portion 93 to prevent the upper vertical portion 88A from slipping out of the mounting hole 92. As a result, the side frames 88 are each coupled to the movable side members 38, and the upper installation member 87 is coupled to and supported by the movable side member 38.

[0268] A plurality of hooks (not shown) are provided on the rear surface of the upper pressure receiving member 74 and are hooked onto the upper installation member 87. By hooking the hooks onto the upper installation member 87, the upper pressure receiving member 74 is connected to the front surface of the upper installation member 87 and is connected to and supported by the front side of the upper installation member 87. The upper pressure receiving member 74 is connected to each of the movable side members 38 via the upper installation members 87.

[0269] In this embodiment, as shown in FIG. 9 , a cylindrical tubular member 94 (also referred to as a collar) is provided on the lower installation member 79. The upper installation member 87 is inserted into the tubular member 94 together with the lower installation member 79 at its lower edge (lower horizontal portion 88D) and coupled to the tubular member 94. This allows the upper pressure-receiving member 74 to be tiltable in the front-rear direction relative to the lower installation member 79. That is, the tubular member 94 functions as a connecting portion between the lower installation member 79 and the upper pressure-receiving member 74. To facilitate assembly of the tubular member 94, a slit (not shown) extending in the left-right direction may be provided on the rear surface of the tubular member 94. The tubular member 94 may be made of metal, resin, or the like.

[0270] 8 , when the movable frame 12 rotates about the rotation axis X and tilts forward, a load that tends to tilt the upper pressure-receiving member 74 forward is applied via the upper installation member 87. Because the upper pressure-receiving member 74 is tiltably connected to the lower installation member 79 via the tubular member 94, the upper pressure-receiving member 74 rotates in response to the tilt of the movable frame 12. Therefore, by connecting the lower installation member 79 and the upper installation member 87 with the tubular member 94, the upper pressure-receiving member 74 can be stably supported by the seat back frame 10 while reducing the effect of tilting of the movable frame 12.

[0271] One end of the lower installation member 79 is inserted into the insertion hole 62 of the flange portion 60 to prevent it from coming off. Therefore, the lower installation member 79 is supported by the flange portion 60 so as to be slidable in the direction of penetration of the insertion hole 62. Therefore, when the upper installation member 87 is pulled upward, the lower installation member 79 can move following it.

[0272] 3A, the left upper portion 85 of the upper pressure receiving member 74 and the left movable member shoulder portion 42 of the movable side member 38 are arranged in positions that are aligned in the vertical direction when viewed from the front. Similarly, the right upper portion 85 of the upper pressure receiving member 74 and the right movable member shoulder portion 42 of the movable side member 38 are arranged in positions that are aligned in the vertical direction when viewed from the front.

[0273] As a result, the upper main portion 84 is positioned at the rear center of the back of the seated person, and the upper side portions 85 are positioned along the left and right sides of the back of the seated person. In other words, the upper pressure-receiving member 74 can be positioned so as to fit along the back of the seated person.

[0274] In this embodiment, as shown in Figure 3A, the lower edge of the upper portion 85 is provided with a notch 95 cut upward. This allows the worker assembling the seat 1 to see the rotating bracket 40 from the front when the movable portion 9 is in the upright position, thereby improving the ease of assembly of the seat 1.

[0275] In Figure 11, a first imaginary plane S1 that runs along the front surface of the lower main part 76 is indicated by a two-dot chain line. As shown in Figure 11, the tubular member 94 is located rearward of the first imaginary plane S1. That is, when viewed in a direction along the front surface of the lower main part 76, the tubular member 94 is disposed rearward of the lower main part 76, and the lower installation member 79 and the upper pressure-receiving member 74 are connected behind the lower main part 76. This prevents a seated occupant from feeling a foreign body sensation due to the connection between the lower installation member 79 and the upper pressure-receiving member 74.

[0276] 11 , a second imaginary plane S2 that runs along the front surface of the upper main portion 84 is indicated by a dashed line. As shown in FIG. 11 , the tubular member 94 is located rearward of the second imaginary plane S2. That is, when viewed in a direction along the front surface of the upper main portion 84, the tubular member 94 is disposed rearward of the upper main portion 84, and the lower installation member 79 and the upper pressure-receiving member 74 are connected behind the upper main portion 84. This prevents a seated occupant from feeling a foreign body sensation due to the connection between the lower installation member 79 and the upper pressure-receiving member 74.

[0277] The lower pressure receiving member 73 may not be connected to the movable frame 12, but may be connected only to the base frame 11 and supported only by the base frame 11. The upper pressure receiving member 74 may not be connected to the base frame 11, but may be connected only to the movable frame 12 and supported only by the movable frame 12. This allows the lower pressure receiving member 73 to rotate relative to the movable frame 12, and the upper pressure receiving member 74 to rotate relative to the base frame 11. This makes it possible to configure a pressure receiving member 72 that can further reduce the effects of tilting of the movable frame 12.

[0278] 2 and 8, the seat back 5 includes an actuator 98 for tilting (rotating) the movable portion 9. The actuator 98 is provided between the base frame 11 and the movable frame 12.

[0279] As shown in FIG. 8 , the actuator 98 includes a motor 98A, a lead screw 98B, and a gearbox 98C that converts the rotation of the motor 98A into linear motion of the lead screw 98B. The gearbox 98C includes a gear and a housing that accommodates the gear. The housing has a through-hole that allows the lead screw 98B to pass through. When the output shaft of the motor 98A rotates, one end of the lead screw 98B protrudes or retracts, moving toward or away from the housing. In this embodiment, the axial direction of the output shaft of the motor 98A and the axial direction of the lead screw 98B are configured to be perpendicular to each other.

[0280] A connecting member 100 is fixed to the movable upper member 39, and the lead screw 98B is connected at its end to the connecting member 100 so as to be rotatable about an axis Y extending in the left-right direction. As a result, the actuator 98 is connected to the movable upper member 39 at the end (the upper end in FIG. 2) of the lead screw 98B so as to be rotatable about the axis Y extending in the left-right direction.

[0281] Since the connecting member 100 is fixed to the movable upper member 39, the actuator 98 is connected to a portion between the two movable member bending portions 43 of the movable frame 12. In addition, as shown in FIG. 3A, the connection portion between the actuator 98 and the movable frame 12 is located between the headrest bending portions 70 in a front view.

[0282] 8, the gearbox 98C is connected to a first connecting bracket 102 so as to be rotatable about an axis Z extending in the left-right direction. The first connecting bracket 102 is fixed to a second connecting bracket 103, and the second connecting bracket 103 is fixed to the base upper member 15. In this way, the gearbox 98C is connected to the base upper member 15 so as to be rotatable about the axis Z extending in the left-right direction.

[0283] As a result, one end of the actuator 98 (corresponding to an end of the gearbox 98C) is rotatably connected to the base upper member 15 about the axis Z extending in the left-right direction. The other end of the actuator 98 (corresponding to the lead screw 98B) is rotatably connected to the movable upper member 39 about the axis Y extending in the left-right direction. Therefore, the movable side member 38 and the corresponding base side member 14, one end of the actuator 98 and the base upper member 15, and the other end of the actuator 98 and the movable upper member 39 are rotatably connected to each other about the axes Y and Z extending in the left-right direction. As a result, the actuator 98 connects the base upper member 15 and the movable upper member 39, and by driving the actuator 98, the movable upper member 39 can be rotated to move toward or away from the base upper member 15.

[0284] In the present embodiment, the actuator 98 is configured to move the movable upper member 39 toward and away from the base upper member 15, but the present invention is not limited to this. Specifically, the actuator 98 may be configured to be connected to the upper part of the base frame 11 other than the base upper member 15 (more specifically, the part above the rotation axis X) and the movable upper member 39, and may be configured to move the movable upper member 39 toward and away from the upper part of the base frame 11.

[0285] When the actuator 98 is driven to move the end of the lead screw 98B in a direction protruding from the gear box 98C, the movable upper member 39 is pushed forward relative to the base upper member 15. As a result, the movable frame 12 rotates around the rotation axis X relative to the base frame 11 in a direction tilting forward relative to the base frame 11.

[0286] When the actuator 98 is driven to move the end of the lead screw 98B in a direction retracting from the gear box 98C, the movable upper member 39 is pulled toward the base upper member 15. As a result, the movable frame 12 rotates around the rotation axis X relative to the base frame 11 in a direction tilting backward relative to the base frame 11.

[0287] In this way, the actuator 98 tilts the movable frame 12 relative to the base frame 11, displacing (specifically, rotating) the movable portion 9 between the forward tilt position and the upright position.

[0288] 2 and 8, at least one of the base frame 11 and the movable frame 12 is provided with a receiving recess 105 that receives at least a portion of the actuator 98. In this embodiment, the receiving recess 105 is provided on the front surface of the base upper member 15, in the center in the left-right direction. As shown in FIG. 2, the receiving recess 105 is formed as a recess that is recessed rearward (in the direction away from the movable upper member 39) on the front surface of the base upper member 15. At least a portion of the actuator 98 (for example, a portion of the motor 98A or the lead screw 98B) is received inside the receiving recess 105 in a side view (see FIG. 4).

[0289] The receiving recess 105 is provided on the front surface of the base upper member 15 at a position where the front panel 20 and the rear panel 21 face each other in the front-rear direction and overlap each other in the front-rear direction.

[0290] As shown in Figure 8, the gearbox 98C is journaled to a first connecting bracket 102. The second connecting bracket 103 is U-shaped and opens rearward. The second connecting bracket 103 is joined (welded in this embodiment) to the top surface and front surface (bottom surface of the receiving recess 105) of the portion of the base upper member 15 where the receiving recess 105 is provided. The first connecting bracket 102 is connected to the front surface of the second connecting bracket 103.

[0291] The second connecting bracket 103 is connected to the front panel 20 and the rear panel 21 of the seat back frame 10 at a position where they face each other. As a result, the actuator 98 is supported via the second connecting bracket 103 at a position where the front panel 20 and the rear panel 21 of the seat back frame 10 face each other. As a result, the actuator 98 can be supported on a portion of the base frame 11 that is highly rigid and less likely to deform.

[0292] Since the connecting member 100 is fixed to the movable upper member 39, the actuator 98 is connected to the movable upper member 39, i.e., the portion between the two movable member bent portions 43 of the movable frame 12. Therefore, the connection portion between the actuator 98 and the movable frame 12 can be located closer to the center of the seat in the left-right direction. This allows the actuator 98 to rotate (tilt) the movable frame 12 more stably than when, for example, the actuator 98 is connected to the movable side member 38.

[0293] However, more specifically, the second connecting bracket 103 is provided at a position offset to either the left or right side of the receiving recess 105. Therefore, the lead screw 98B is disposed at a position offset to either the left or right side (the vehicle exterior side in this embodiment) of the receiving recess 105. This arrangement ensures a sufficient space to accommodate the motor 98A between the lead screw 98B and the wall surface that defines the edge of the receiving recess 105 on the other left or right side (the vehicle interior side in this embodiment).

[0294] 12 , when the movable section 9 is in the upright position (when the movable upper member 39 is at the rearmost position), the movable member shoulder 42 is located behind the pivot bracket 40 in a top view. At least a portion of the movable member shoulder 42 is located in front of the mounting bracket 90 (the portion connecting the upper installation member 87 and the movable frame 12). However, the entire movable member shoulder 42 may be located in front of the mounting bracket 90. At least a portion of the mounting bracket 90 is located in front of the actuator 98, and preferably the entire mounting bracket 90 is located in front of the actuator 98.

[0295] By configuring in this way, the standing position can be set to an appropriate position where the movable part 9 does not tilt too far forward or backward and a large occupant can sit in a relaxed manner.

[0296] Furthermore, since the mounting bracket 90 is located in front of the actuator 98 and the upper pressure-receiving member 74 is supported on the front side of the upper installation member 87, the upper pressure-receiving member 74 is disposed in front of the actuator 98. This prevents the actuator 98 from giving a foreign body sensation to the seat occupant.

[0297] As shown in Figures 13 and 14, when the movable part 9 is in a forward tilted position (when the movable upper member 39 is positioned at the forwardmost position), the part (flange part 60) where the lower installation member 79 and the seat back frame 10 are connected is located rearward of the front end of the actuator 98.

[0298] With this configuration, the forward tilt position can be set to an appropriate position that can support the back of a relatively small seated occupant.

[0299] 2, when the movable section 9 is in the upright position, the upper main section 84 and the left and right upper sections 85 of the upper pressure-receiving member 74 are each located above the rotation axis X (see also FIG. 4). As a result, by tilting the movable frame 12 forward, the upper pressure-receiving member 74 can be rotated from a position where its upper portion is tilted backward to a position where it protrudes forward and stands upright (see FIG. 14). Therefore, by rotating the movable frame 12, the upper pressure-receiving member 74 can be supported by the movable frame 12 so as to be able to support the back of a small seated person.

[0300] 14 , whether the movable portion 9 is in the upright position or the forward tilted position, at least a portion of the actuator 98 is located behind the upper pressure-receiving member 74. In addition, at least a portion of the actuator 98 is located behind the headrest frame 64.

[0301] <Seat Manufacturing Method> Next, a description will be given of a manufacturing method of the seat 1. The manufacturing method of the seat 1 includes a first step of manufacturing the base frame 11, a second step of rotatably assembling the movable frame 12 to the base frame 11, a third step of assembling the upper installation member 87 and the lower installation member 79 to the first installation member and the second installation member, respectively, a fourth step of assembling the first installation member and the second installation member, and a fifth step of connecting the actuator 98 to the movable frame 12 and the base frame 11. After the fifth step, the headrest 6, the padding member, and the upholstery material are sequentially assembled.

[0302] The first process includes a process of manufacturing the front panel 20 and the rear panel 21 by press working, and a process of joining the front panel 20 and the rear panel 21 at their peripheral edges to form the base frame 11. The front panel 20 and the rear panel 21 may be joined by welding, or may be joined by fastening with bolts and nuts.

[0303] The first step may include a step of inserting and fixing the stud bolt 52 into the first through-hole 53 of the front panel 20. This step may be performed before the step of joining the front panel 20 and the rear panel 21 together.

[0304] The first step may also include a step of fixing (in this embodiment, welding) the second connecting bracket 103 to the base upper member 15. This step may be performed after the front panel 20 and the rear panel 21 are joined together. In this step, the second connecting bracket 103 may be joined (welded) to the top and bottom surfaces of the base upper member 15.

[0305] The second step includes a step of fixing the connecting member 100 to the movable frame 12 by welding or the like, a step of fixing the headrest frame 64 to the movable frame 12, a step of rotatably coupling the movable frame 12 to the pivot bracket 40, and a step of fixing the pivot bracket 40 to the base frame 11. The step of fixing the headrest frame 64 to the movable frame 12 includes a step of coupling (by welding in this embodiment) the lower end of the vertical portion 65 to the movable member bent portion 43 of the movable frame 12. The step of rotatably coupling the movable frame 12 to the pivot bracket 40 includes a step of inserting a pin 49 into a through-hole 48 provided in the lower end of the movable side member 38 and rotatably coupling the lower end of the movable side frame to the bulging portion 45B of the pivot bracket 40.

[0306] The process of fixing the pivoting bracket 40 to the base frame 11 can include the process of inserting a stud bolt 52 provided in a first through-hole 53 of the front panel 20 into a front bolt hole 50A to position the pivoting bracket 40, and then inserting a bolt 56 into a rear bolt hole 50B and a second through-hole 54 of the pivoting bracket 40 and engaging a nut 57 to couple (in this embodiment, fasten) the pivoting bracket rear portion 46 and the front panel 20. This allows the worker to position the pivoting bracket 40 once, and then perform the work of coupling the pivoting bracket 40 to the base frame 11, thereby making the assembly process easier.

[0307] The process of fixing the pivot bracket 40 to the base frame 11 may also include a process of attaching nuts 55 to the stud bolts 52 to join the pivot bracket front portion 45 and the front panel 20 together.

[0308] The third step may include a step of connecting the hook provided on the rear surface of the upper pressure-receiving member 74 to the upper installation member 87, and a step of connecting the hook provided on the rear surface of the lower pressure-receiving member 73 to the lower installation member 79. In addition, the third step may include a step of connecting the upper installation member 87 and the lower installation member 79 with a tubular member 94.

[0309] The fourth step includes inserting the end of the upper installation member 87 from below into the mounting hole 92 provided in the flange portion 91 of the mounting bracket 90, and inserting the end of the lower installation member 79 from above into the insertion hole 62 provided in the flange portion 60 of the pivot bracket 40. In the step of inserting the end of the upper installation member 87 from below, the worker may insert the end of the upper installation member 87 above the position where it will be located after installation (also referred to as overstroking), and then perform the step of inserting the end of the lower installation member 79 from above into the insertion hole 62. This allows the lower installation member 79 to be installed after the upper installation member 87 is assembled, thereby improving the ease of assembly.

[0310] The fifth step includes a step of rotatably connecting the first connecting bracket 102 to the gearbox 98C, a step of fixing the first connecting bracket 102 to the second connecting bracket 103, and a step of rotatably connecting the end of the lead screw 98B to the connecting member 100. Through these three steps, the actuator 98 is connected to the base frame 11 and the movable frame 12.

[0311] Next, the effects of the sheet 1 will be described.

[0312] 2, the pressure-receiving member 72 that supports the weight of a seated occupant includes a lower pressure-receiving member 73 provided on the base frame 11 and an upper pressure-receiving member 74 provided on the movable frame 12. Therefore, stress is less likely to be generated inside the pressure-receiving member 72 than when the upper pressure-receiving member 74 and the lower pressure-receiving member 73 are configured as an integral unit, and the pressure-receiving member 72 is more likely to follow the tilting of the movable part 9.

[0313] In this embodiment, the upper installation member 87 is connected to the lower installation member 79 via a tubular member 94. Therefore, the upper pressure-receiving member 74 is connected to the lower installation member 79 so as to be tiltable in the front-to-rear direction. This allows the upper and lower parts of the upper pressure-receiving member 74 to be well supported by the movable frame 12, and also allows the upper pressure-receiving member 74 to well follow the tilt of the movable frame 12.

[0314] The base frame 11 (base upper member 15) is provided with a receiving recess 105 that receives at least a portion of the actuator 98. By providing the receiving recess 105 that is recessed rearward in the base upper member 15 in this manner, a space for accommodating a functional component can be formed within the receiving recess 105. Furthermore, the actuator 98 and the base frame 11 are arranged so as to overlap in a side view. This allows the actuator 98 to be arranged compactly (i.e., so that the thickness of the upper part of the seat back frame 10 is reduced).

[0315] The actuator 98 is disposed between the base frame 11 and the movable frame 12. Therefore, by forming the receiving recess 105 so as to be recessed rearward on the front surface of the base upper member 15, the actuator 98 can be easily accommodated in the receiving recess 105.

[0316] Furthermore, the headrest frame 64 is coupled to the rear surface of the movable frame 12 and is supported by the movable frame 12. Therefore, the connecting portion of the headrest frame 64 to the movable frame 12 does not protrude forward beyond the movable frame 12. Therefore, the headrest frame 64 can be connected to the movable frame 12 while preventing the seated occupant from feeling a foreign body sensation.

[0317] The movable frame 12 is connected to the front panel 20 via the pivot bracket 40, and the airbag module 24 is connected to the rear panel 21. With this configuration, the movable frame 12 and the airbag module 24 can be more easily disposed at a greater distance than when the movable frame 12 and the airbag module 24 are provided on the same panel. This reduces the influence of rotation of the movable frame 12 on the airbag module 24. Furthermore, because the deployment of the airbag 25 is prevented from being hindered by the movable frame 12, the airbag 25 can be deployed smoothly, thereby improving the safety of the seat 1.

[0318] In this embodiment, the pivot bracket 40 is located above the joint portion (rear joint portion 32) of the rear panel 21 with the airbag module 24. As a result, the joint portion (front joint portion 58) of the front panel 20 with the movable frame 12 is located above the joint portion (rear joint portion 32) of the rear panel 21 with the airbag module 24. Therefore, the movable frame 12 and the airbag module 24 are joined at positions spaced apart in the up-down direction of the base frame 11, preventing the deployment of the airbag 25 from being hindered by the movable frame 12.

[0319] Furthermore, whether the movable portion 9 is in the forward tilt position or the upright position, at least a portion of the actuator 98 is located behind the upper pressure-receiving member 74. Therefore, compared to when the entire actuator 98 is located in front of the upper pressure-receiving member 74, it is possible to prevent the actuator 98 from giving a foreign body sensation to the seat occupant.

[0320] Although the description of the specific embodiment has been completed above, the present invention is not limited to the above embodiment and can be widely modified and implemented.

[0321] For example, in the above embodiment, an example is described in which the pressure receiving member 72 is configured by the upper pressure receiving member 74 and the lower pressure receiving member 73, but the pressure receiving member 72 may be configured by two or more plate members arranged approximately parallel to the backrest surface 5S. In this case, each of the plate members may be joined at both ends to either the seat back frame 10 or the movable frame 12, and may be rotatably connected to an adjacent plate member around a rotation axis X extending in the left-right direction.

[0322] In the above embodiment, the receiving recess 105 is provided in the base frame 11, but it may also be provided in the movable frame 12. In that case, the receiving recess 105 is formed so as to be recessed forward in the movable upper frame, and at least a portion of the lead screw 98B is housed in the receiving recess 105. Alternatively, the receiving recess 105 may be provided in each of the base frame 11 and the movable frame 12. In the above embodiment, an example has been described in which the actuator 98 is housed in the receiving recess 105, but it is also possible to house various functional components other than the actuator 98 in the receiving recess 105.

[0323] In the above embodiment, an example in which the present invention is applied to a vehicle seat has been described, but the seat 1 according to the present invention can also be applied to various seats for aircraft, trains, etc. Furthermore, not all of the components of the seat 1 shown in the above embodiment are necessarily required, and can be selected as appropriate.

[0324] DESCRIPTION OF SYMBOLS 1: Seat (an example of a vehicle seat) 5: Seat back 10: Seat back frame 11: Base frame 12: Movable frame 14: Base side member 20: Front panel (an example of a front member) 21: Rear panel (an example of a rear member) 24: Airbag module 24L: Outer airbag module 24R: Inner airbag module 25: Airbag 32: Rear connecting portion 40: Rotating bracket (an example of a bracket) 45A: Plate portion 45B: Bulging portion 48: Through hole 58: Front connecting portion 60: Flange portion 62: Insertion hole (an example of a through hole) 73: Lower pressure receiving member (an example of a pressure receiving member) 82: Mounting portion 91: Flange portion P: Closed cross-sectional structure

Claims

1. A vehicle seat, wherein a seatback frame forming the skeleton of a seatback has a base frame and a movable frame rotatably connected to the base frame, an airbag module is provided on the base frame, the base frame has a front member that receives the load of an occupant, and a rear member that is connected to the front member and cooperates with the front member to form a closed cross-sectional structure, the movable frame is connected to the front member, and the airbag module is connected to the rear member.

2. The vehicle seat according to claim 1, wherein the movable frame is connected to a front joint portion of the front member, and the airbag module is connected to a rear joint portion of the rear member, the front joint portion being located above the rear joint portion.

3. The vehicle seat according to claim 2, wherein the movable frame is connected to the front joint via a bracket, the bracket being located above the rear joint.

4. A vehicle seat as claimed in claim 2 or 3, wherein the front joint portions are provided in front of and behind the rear joint portion.

5. A vehicle seat as described in claim 3, wherein the bracket has a plate portion arranged along the seat inner side surface of the front member and a bulging portion that bulges toward the seat inner side and is spaced apart from the seat inner side surface of the front member, and the movable frame is rotatably connected to the seat inner side surface of the bulging portion.

6. A vehicle seat as claimed in claim 3, wherein the base frame includes a pair of base side members extending in the vertical direction, a pressure-receiving member supported via an installation member is provided between the base side members, and the bracket has an attachment portion for attaching one end of the installation member.

7. The vehicle seat according to claim 6, wherein the front joint portions are provided in front of and behind the mounting portion.

8. A vehicle seat as described in claim 6 or claim 7, wherein the mounting portion has a plate-shaped flange portion having a surface facing in the vertical direction, and a through hole provided in the flange portion through which the installation member is inserted.

9. The vehicle seat according to claim 3, wherein the airbag module constitutes an outer airbag module coupled to the outer side of the base frame, an inner airbag module including a near-side airbag is further provided on the inner side of the base frame, and the bracket is positioned between the outer airbag module and the inner airbag module.

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