WO2025109957A1 - Vehicular seat frame and vehicular seat - Google Patents

Abstract

Provided is a vehicular seat frame capable of suppressing shifting of a seated occupant's back and having a simple configuration. This vehicular seat frame (20) comprises: a floor attachment part (21) attached to a vehicle body floor part; a cushion frame rear part (50) constituting a rear part of the skeleton of a seat cushion (12); a cushion frame front part (48) constituting a front part of the skeleton of the seat cushion (12) and connected to the cushion frame rear part (50) so as to be rotatable around a middle folding shaft (52); a front link (26) rotatably connected to the cushion frame front part (48) and the floor attachment part (21); a seat back frame (24) that is provided on the rear end side of the cushion frame rear part (50) and constitutes the skeleton of a seat back (14); and a recliner (28) that is disposed between the cushion frame rear part (50) and the floor attachment part (21) and that allows the cushion frame rear part (50) to rotate relative to the floor attachment part (21) around the axis of the recliner in a state in which a recline lever (84) that can be operated by the occupant is unlocked.

Description

Vehicle seat frame and vehicle seat

This disclosure relates to vehicle seats, and in particular to vehicle seat frames.

Patent Publication No. 6962845 discloses a vehicle seat that prevents the relative positional shift between the occupant's back and the seat back when the seat back is reclined (hereinafter referred to as "back shift"). This vehicle seat includes a rear cushion frame that is rotatable around a rear axis relative to the vehicle body floor, a front cushion frame that is connected to the rear cushion frame so as to be rotatable around a folding axis, and a seat back frame that is provided on the rear end side of the rear cushion frame. This vehicle seat also includes a drive mechanism that moves the front cushion frame and the rear cushion frame relative to each other in the up-down direction of the seat between a non-reclining state in which the rear cushion frame extends from the front cushion frame to the rear of the seat, and a reclining state in which the rear cushion frame is inclined rearward and downward relative to the front cushion frame.

JP 2005-319341 A discloses a seat reclining device in which the seat cushion's bearing surface angle changes in conjunction with the rearward tilt of the seat back, reducing movement of the hip point on the seat cushion. In this seat reclining device, a base plate is mounted on the vehicle body, and an arm is rotatably supported on the base plate. The seat back is fixed to the arm, and one end of an interlocking plate is rotatably attached to the arm. The other end of the interlocking plate is fixed to the rear of the seat cushion, and the front of the seat cushion is supported by a bracket mounted on the vehicle body so that it can move back and forth. This allows the seat cushion's bearing surface angle to change according to the tilt angle of the seat back.

The vehicle seat disclosed in Japanese Patent No. 6962845 has a complex structure because the drive mechanism includes three motors and requires a control device to control the operation of each motor. On the other hand, the seat reclining device disclosed in Japanese Patent Application Laid-Open No. 2005-319341 is a manual type that does not require a motor or control device, so it has a simple structure, but the back can shift.

　In consideration of the above, the present disclosure aims to provide a vehicle seat frame and a vehicle seat that are simple in configuration and can prevent the back from shifting.

The vehicle seat frame of the first embodiment includes a floor attachment portion attached to the vehicle body floor, a rear cushion frame portion constituting the rear of the seat cushion skeleton, a front cushion frame portion constituting the front of the seat cushion skeleton and connected to the rear cushion frame portion rotatably about a folding axis having the seat width direction as its axis, a front link connected to the front cushion frame portion rotatably about an upper front axis having the seat width direction as its axis and connected to the floor attachment portion rotatably about a lower front axis having the seat width direction as its axis, a seat back frame provided at the rear end side of the rear cushion frame portion and constituting the skeleton of the seat back, and a recliner disposed between the rear cushion frame portion and the floor attachment portion with the seat width direction as its axis, having an operating portion operable by an occupant, and allowing the rear cushion frame portion to rotate about its own axis relative to the floor attachment portion when the operating portion is unlocked.

In the first embodiment of the vehicle seat frame, a rear portion of the cushion frame that constitutes the rear portion of the skeleton of the seat cushion and a front portion of the cushion frame that constitutes the front portion of the skeleton of the seat cushion are rotatably connected around a folding axis whose axis is the seat width direction. A front link is connected to the front portion of the cushion frame so as to be rotatable around an upper front axis whose axis is the seat width direction. This front link is connected to the floor mounting portion so as to be rotatable around a lower front axis whose axis is the seat width direction. A seat back frame that constitutes the skeleton of the seat back is erected from the rear end side of the rear portion of the cushion frame. A recliner is disposed between the rear portion of the cushion frame and the floor mounting portion, with its axis directed to the seat width direction. This recliner has an operating portion that can be operated by an occupant.

When the operating unit is in the unlocked state, the rear part of the cushion frame is allowed to rotate around the axis of the recliner relative to the floor attachment part. In this state, the floor attachment part, rear part of the cushion frame, front part of the cushion frame, and front link can be operated as a four-joint link mechanism. This operation causes the front part of the cushion frame and the rear part of the cushion frame to rotate relatively around the folding axis, and the rear part of the cushion frame to rotate around the axis of the recliner. This allows the seat back frame attached to the rear end side of the rear part of the cushion frame to be reclined (tilted backward). At this time, the rear part of the cushion frame is reclined around the folding axis together with the seat back frame, preventing the occupant's back from shifting. Moreover, a manual type can be used as the recliner, simplifying the configuration.

The second aspect of the vehicle seat frame is the first aspect, in which the operating section has a recliner lever rotatably attached to the rear of the cushion frame or the seatback frame, and an operating force transmission section that transmits the operating force of the recliner lever to the recliner.

In the second embodiment of the vehicle seat frame, when the recliner lever, which is rotatably attached to the rear of the cushion frame or the seatback frame, is rotated, the operating force of the recliner lever is transmitted to the recliner via the operating force transmission unit. This allows the recliner to be released from restriction. The above-mentioned recliner lever can be positioned in a position that is easily reachable by the occupant, improving operability for the occupant.

The vehicle seat frame of the third aspect is the first or second aspect, and is provided with a spiral spring that is arranged coaxially with the recliner and biases the rear of the cushion frame in the direction in which the seatback frame stands up.

In the vehicle seat frame of the third embodiment, the rear of the cushion frame is biased in the direction in which the seatback frame stands up by a spiral spring that is arranged coaxially with the recliner. Therefore, when the seatback is in the reclined state, the occupant can release the restriction of the recliner to cause the seatback to stand up by the biasing force of the spiral spring.

The fourth aspect of the vehicle seat frame is any one of the first to third aspects, in which the rear of the cushion frame and the seat back frame are integrally connected.

In the fourth embodiment of the vehicle seat frame, the rear of the cushion frame and the seatback frame are integrally connected, which reduces the number of parts and the labor required to assemble the parts.

The fifth aspect of the vehicle seat includes a seat cushion on which an occupant sits and a seat back that supports the occupant's back, and the framework of the seat cushion and the seat back is formed by a vehicle seat frame of any one of the first to fourth aspects.

In the vehicle seat of the fifth aspect, the back of the occupant seated on the seat cushion is supported by the seat back. The framework of the seat cushion and the seat back is formed by the vehicle seat frame of any one of the first to fourth aspects, so the above-mentioned effects are obtained.

As described above, the present disclosure provides a vehicle seat frame and a vehicle seat that are simple in structure and can prevent the back from shifting.

1 is a side view showing a vehicle seat according to an embodiment; 1 is a side view showing a state in which a seat back frame of a vehicle seat according to an embodiment is reclined. 1 is a first perspective view showing a main portion of a vehicle seat frame according to an embodiment; FIG. 2 is a second perspective view showing a main portion of the vehicle seat frame according to the embodiment. FIG. 4 is a third perspective view showing a main portion of the vehicle seat frame according to the embodiment.

Below, a vehicle seat 10 according to an embodiment of the present disclosure will be described with reference to Figures 1 to 5. Note that in each figure, some reference symbols may be omitted to make the drawings easier to read. Additionally, arrows FR, UP, and LH shown as appropriate in each figure indicate the front, top, and left of the vehicle seat 10, respectively. In the following description, when the front-rear, left-right, top-bottom directions are used, they will indicate directions relative to the vehicle seat 10, unless otherwise specified.

As shown in FIG. 1, the vehicle seat 10 includes a seat cushion 12 on which an occupant P sits, a seat back 14 that supports the back of the occupant P, and a headrest 16 that supports the head of the occupant P. The framework of the seat cushion 12 and the seat back 14 is formed by a vehicle seat frame 20 according to an embodiment of the present disclosure.

As shown in Figures 1 to 5, the vehicle seat frame 20 includes a floor mounting portion 21 that is attached to the vehicle body floor (not shown), a seat cushion frame 22 that forms the skeleton of the seat cushion 12, a pair of left and right front links 26, a seat back frame 24 that forms the skeleton of the seat back 14, a pair of left and right recliners 28 that are arranged between the seat cushion frame 22 and the floor mounting portion 21, and a headrest frame 30 that forms the skeleton of the headrest 16.

The seat cushion frame 22, the seat back frame 24, and the headrest frame 30 are fitted with pads (not shown) covered with skins 32, 34, and 36 (not shown in any figures except FIG. 1). The occupant P shown in FIG. 1 and FIG. 2 is, for example, an AM50 (50th percentile American adult male) dummy.

The floor mounting portion 21 is configured to include a pair of left and right slide rails 38 and a pair of left and right risers 40. The left and right slide rails 38 are disposed below both left and right ends of the seat cushion 12. Each slide rail 38 has a lower rail 42 and an upper rail 44. The lower rail 42 and the upper rail 44 are configured, for example, from a press-formed metal plate, and are formed in an elongated shape with the longitudinal direction being the longitudinal direction.

The front and rear ends of the lower rail 42 are fixed to the vehicle floor via two front and rear brackets (reference numbers omitted). The upper rail 44 is supported so that it can slide in the front-to-rear direction relative to the lower rail 42. An unlock lever 46 is installed between the front ends of the left and right upper rails 44. When this unlock lever 46 is operated, the lock mechanism (not shown) is unlocked, allowing the left and right upper rails 44 to slide relative to the left and right lower rails 42.

The left and right risers 40 are made of, for example, press-formed metal plates, and are long plates with the longitudinal direction being the front-to-rear direction and the main thickness direction being the left-to-right direction (seat width direction). The lower ends of the left and right risers 40 are provided with lower flange portions (reference numerals omitted) that are bent inward in the left-to-right direction. The lower flange portions of the left and right risers 40 are superimposed on the upper surfaces of the left and right upper rails 44, and are fixed to the left and right upper rails 44 by means of bolt fastening or the like.

The seat cushion frame 22 is configured such that a cushion frame front part 48 that constitutes the front part of the skeleton of the seat cushion 12 and a cushion frame rear part 50 that constitutes the rear part of the skeleton of the seat cushion 12 are rotatably connected via left and right shoulder bolts 52.

The cushion frame front portion 48 comprises a pair of left and right side frame portions 54, a front frame portion 56 that spans between the upper front ends of the left and right side frame portions 54, and a pipe frame portion 58 that spans between the rear ends of the left and right side frame portions 54. The left and right side frame portions 54 and the front frame portion 56 are made of, for example, press-formed metal plates, and the pipe frame portion 58 is made of, for example, a metal pipe.

The cushion frame rear portion 50 comprises a pair of left and right side frame portions 60, a pipe frame portion 62 that spans between the front ends of the left and right side frame portions 60, and a rear frame portion 64 that spans between the rear ends of the left and right side frame portions 60. The left and right side frame portions 60 are made of, for example, press-formed metal plates, and the pipe frame portion 62 and rear frame portion 64 are made of, for example, metal pipes. A plurality of seat cushion springs 66 are spanned between the pipe frame portion 62 and the rear frame portion 64.

A connecting portion 60A extending downward is provided at the front-rear middle portion of the left and right side frame portions 60. The lower ends of the left and right connecting portions 60A are positioned inside the left and right risers 40 in the left-right direction. A recliner 28 is respectively positioned between the lower ends of the left and right connecting portions 60A and the left and right risers 40. The left and right recliners 28 are well-known manual recliners, and are positioned with their axis in the left-right direction. The left and right recliners 28 are fixed to the left and right connecting portions 60A and the left and right risers 40 by means such as welding.

The rear ends of the left and right side frame sections 54 of the cushion frame front section 48 are overlapped with the front ends of the left and right side frame sections 60 of the cushion frame rear section 50 from the outside in the seat width direction. Then, left and right shoulder bolts 52 that pass through the rear ends of the left and right side frame sections 54 and the front ends of the left and right side frame sections 60 are screwed into nuts (not shown). This connects the cushion frame front section 48 and the cushion frame rear section 50 so that they can rotate relatively around the left and right shoulder bolts 52.

The left and right stepped bolts 52 have their axial direction in the left-right direction (seat width direction) and are arranged coaxially with each other. In this embodiment, as shown in FIG. 1, the difference (positional deviation) in the positioning in the fore-aft direction of the seat back between the left and right stepped bolts 52 and the hip point HP of the occupant P is set small. Note that the fore-aft direction of the seat back is a direction perpendicular to the torso line of the occupant P in a side view of the seat. The left and right stepped bolts 52 correspond to the "bending axis" in this disclosure. Hereinafter, the stepped bolts 52 may be referred to as the "bending axis 52".

The seatback frame 24 comprises left and right side frame portions 68, an upper frame portion 70 that spans between the upper ends of the left and right side frame portions 68, and a back panel portion 72 that spans between the lower ends of the left and right side frame portions 68. The left and right side frame portions 68 and the back panel portion 72 are made of, for example, press-formed metal plates, and the upper frame portion 70 is made of, for example, metal pipes. A plurality of seatback springs 74 are spanned between the left and right side frame portions 68. A headrest frame 30 that forms the framework of the headrest 16 is connected to this upper frame portion 70. The headrest frame 30 is made of, for example, metal pipes, and is roughly inverted U-shaped when viewed in the front-to-rear direction.

The seatback frame 24 configured as described above is provided on the rear end side of the cushion frame rear portion 50. Specifically, the rear ends of the left and right side frame portions 60 of the cushion frame rear portion 50 are provided with backframe connecting portions 60B extending upward. The lower ends of the left and right side frame portions 68 of the seatback frame 24 are overlapped with the left and right backframe connecting portions 60B from the inside in the left-right direction. The left and right side frame portions 68 are fixed to the left and right backframe connecting portions 60B by means of, for example, welding, bolt fastening, or other means.

The left and right front links 26 are formed into an elongated shape, for example from a press-formed metal plate. The upper parts of the left and right front links 26 are overlapped from the inside in the left-right direction against the front ends of the left and right side frame parts 54 of the cushion frame front part 48. The lower parts of the left and right front links 26 are overlapped from the inside in the left-right direction against the front parts of the left and right risers 40.

The upper ends of the left and right front links 26 are connected in the left-right direction by a front pipe 76. The front pipe 76 corresponds to the "upper front axle" in this disclosure. This front pipe 76 is made of, for example, a metal pipe, and is arranged with its axis in the left-right direction. Both axial ends of the front pipe 76 pass through the left and right front links and are fixed to the left and right front links 26 by means such as welding.

Furthermore, both axial ends of the front pipe 76 pass through the left and right side frame portions 54 of the cushion frame front portion 48 and are connected to the left and right side frame portions 54 by means of rivets or the like. The front pipe 76 is rotatable relative to the left and right side frame portions 54. As a result, the left and right front links 26 are rotatably connected to the left and right side frame portions 54 around an axis along the left-right direction.

Left and right stepped bolts 78 penetrate the left and right risers 40 from the outside in the left-right direction through the lower ends of the left and right front links 26, and each stepped bolt 78 is screwed into a nut (not shown). The left and right stepped bolts 78 each correspond to the "lower front axle" in this disclosure. The left and right stepped bolts 78 have an axial direction in the left-right direction, and the left and right front links 26 are connected to the left and right risers 40 so as to be rotatable relative to each other around the left and right stepped bolts 78.

The left and right recliners 28, which are arranged between the rear cushion frame 50 and the left and right risers 40, are connected by a reclining shaft 80 whose axis is in the left-right direction, and are configured to move in unison by the rotation of the reclining shaft 80. A first reclining lever 82 and a spiral spring 88 are arranged on the left-right outer side of the rear end of the left riser 40. A spiral spring 88 is also arranged on the left-right outer side of the rear end of the right riser 40. Note that the spiral spring 88 is shown diagrammatically in Figures 1 to 5. The first reclining lever 82 is formed into an elongated shape, for example, from a press-formed metal plate, and is arranged with its longitudinal direction in the front-rear direction. The rear end of the first reclining lever 82 is fixed to the reclining shaft 80.

This first reclining lever 82 can be rotated around the reclining shaft 80. This first reclining lever 82 constitutes part of the "operating unit" in this disclosure. When the front part of this first reclining lever 82 is lifted upward, the reclining shaft 80 rotates in one direction around its axis together with the first reclining lever 82. In this state, the left and right recliners 28 are unlocked, and the rear part 50 of the cushion frame is allowed to rotate around the axis of the left and right recliners 28 relative to the left and right risers 40.

When the rear cushion frame 50 rotates relative to the left and right risers 40, the rear cushion frame 50, the front cushion frame 48, the left and right front links 26, and the left and right risers 40 operate as a four-joint link mechanism (see the dashed lines labeled FL in Figures 1 to 5). This action causes the front cushion frame 48 and the rear cushion frame 50 to rotate relative to each other around the folding axis 52, and the rear cushion frame 50 to rotate around the axis of the left and right recliners 28. This allows the seat back frame 24 attached to the rear end side of the rear cushion frame 50 to be reclined, as shown in Figure 2. At this time, the rear cushion frame 50 is configured to recline together with the seat back frame 24 around the folding axis.

The left and right spiral springs 88 are arranged coaxially with the left and right recliners 28. The inner ends of the left and right spiral springs 88 are engaged with the left and right risers 40, and the outer ends of the left and right spiral springs 88 are engaged with the left and right side frame portions 60 of the cushion frame rear portion 50. These spiral springs 88 urge the cushion frame rear portion 50 in the direction in which the seatback frame 24 stands up.

A second reclining lever 84 is attached to the left side frame section 60 of the cushion frame rear section 50. The second reclining lever 84 corresponds to the "reclining lever" in this disclosure and constitutes part of the "operating section" in this disclosure. This second reclining lever 84 is formed in an elongated shape, for example from a press-formed metal plate, and is positioned on the left-right outer side of the left side frame section 60 with the front-to-rear direction as the longitudinal direction. The rear end of the second reclining lever 84 is attached to the back frame connecting section 60B of the left side frame section 60 so as to be rotatable around a rotation axis 90 whose axial direction is the left-right direction.

A recliner cable 86, which is an operating force transmission unit, is stretched between the second recliner lever 84 and the first recliner lever 82 described above. The recliner cable 86 constitutes a part of the "operating unit" in this disclosure. When the front part of the second recliner lever 84 is lifted upward, the second recliner lever 84 rotates upward around the rotation axis 90. The operating force applied to the second recliner lever 84 is transmitted to the first recliner lever 82 by the recliner cable 86, and the reclining shaft 80 is configured to rotate in one direction around the axis line together with the first recliner lever 82. In this state, the left and right recliners 28 are unlocked, and the rear part 50 of the cushion frame is allowed to rotate around the axis line of the left and right recliners 28 relative to the left and right risers 40. The operating force transmission unit is not limited to the recliner cable 86, and may be a link or the like.

Next, the operation and effects of this embodiment will be described.
In the vehicle seat 10 configured as described above, the back of an occupant seated on the seat cushion 12 is supported by the seat back 14. The framework of the seat cushion 12 and the seat back 14 is formed by a vehicle seat frame 20. In this vehicle seat frame 20, a cushion frame rear portion 50 constituting the rear portion of the framework of the seat cushion 12 and a cushion frame front portion 48 constituting the front portion of the framework of the seat cushion 12 are rotatably connected around a folding axis 52 whose axial direction is in the left-right direction (seat width direction).

The front link 26 is connected to the cushion frame front part 48 so as to be rotatable around a front pipe 76 whose axis is in the left-right direction. The front link 26 is connected to the floor mounting part 21 so as to be rotatable around a shoulder bolt 78 whose axis is in the seat width direction. The seat back frame 24, which forms the framework of the seat back 14, stands upright from the rear end side of the cushion frame rear part 50. The recliner 28 is disposed between the cushion frame rear part 50 and the floor mounting part 21 with its axis directed in the seat width direction. The recliner 28 has a first recliner lever 82 and a second recliner lever 84 that can be operated by the occupant.

When the first reclining lever 82 or the second reclining lever 84 is in the unlocked state, the cushion frame rear part 50 can rotate around the axis of the recliner 28 relative to the floor attachment part 21. In this state, the floor attachment part 21, the cushion frame rear part 50, the cushion frame front part 48, and the front link 26 can be operated as a four-joint link mechanism. This operation causes the cushion frame front part 48 and the cushion frame rear part 50 to rotate relatively around the folding axis 52, and the cushion frame rear part 50 to rotate around the axis of the recliner 28. This allows the seat back frame 24 provided on the rear end side of the cushion frame rear part 50 to be reclined. At this time, the cushion frame rear part 50 is reclined around the folding axis 52 together with the seat back frame 24, so that the occupant's back can be prevented from shifting. Moreover, since a manual type can be adopted as the above-mentioned recliner 28, the configuration can be simplified.

In addition, in this embodiment, when the second recliner lever 84, which is rotatably attached to the rear cushion frame 50, is rotated, the operating force is transmitted to the recliner 28 via the recliner cable 86. This allows the restriction on the recliner 28 to be released. The second recliner lever 84 is positioned in a position that is easier for the occupant to reach than the first recliner lever 82, improving operability for the occupant.

In addition, in this embodiment, the cushion frame rear portion 50 is biased in the direction in which the seatback frame 24 stands up by a spiral spring 88 arranged coaxially with the recliner 28. Therefore, when the seatback 14 is in the reclined state, the occupant can release the restriction of the recliner 28 to cause the seatback 14 to stand up by the biasing force of the spiral spring 88.

In the above embodiment, the left and right side frame portions 60 of the cushion frame rear portion 50 and the left and right side frame portions 68 of the seatback frame 24 are manufactured separately and fixed by means of welding, bolt fastening, or the like, but this is not limited to the above. The left and right side frame portions 60 and the left and right side frame portions 68 may also be manufactured as one integral part. This can reduce the number of parts and the labor required to assemble the parts.

In addition, in the above embodiment, the second reclining lever 84 is attached to the rear part 50 of the cushion frame, but this is not limiting, and the second reclining lever 84 may be attached to the seat back frame 24. Also, one of the first reclining lever 82 and the second reclining lever 84 may be omitted.

In addition, this disclosure can be modified in various ways without departing from the spirit of the disclosure. Furthermore, the scope of the rights of this disclosure is not limited to the above-described embodiment.

In addition, the disclosure of Japanese Patent Application No. 2023-198551, filed on November 22, 2023, is incorporated herein by reference in its entirety. All documents, patent applications, and technical standards described herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims (5)

A floor mounting portion that is attached to a vehicle body floor portion;
a rear cushion frame portion constituting a rear portion of the framework of the seat cushion;
a cushion frame front portion that constitutes a front portion of a skeleton of the seat cushion and is connected to the cushion frame rear portion so as to be rotatable about a center bending axis whose axial direction is the seat width direction;
a front link rotatably connected to the cushion frame front portion about an upper front shaft having an axial direction parallel to the seat width direction, and rotatably connected to the floor mounting portion about a lower front shaft having an axial direction parallel to the seat width direction;
a seat back frame provided on a rear end side of the rear portion of the cushion frame and constituting a framework of the seat back;
a recliner that is disposed between the rear portion of the cushion frame and the floor attachment portion with the seat width direction as an axial direction, has an operation unit that can be operated by an occupant, and allows the rear portion of the cushion frame to rotate relative to the floor attachment portion around its own axis when the operation unit is in an unlocked state;
A vehicle seat frame comprising: The operation unit includes:
a recliner lever rotatably attached to the rear portion of the cushion frame or the seat back frame;
an operating force transmission unit that transmits an operating force of the recliner lever to the recliner;
2. The vehicle seat frame according to claim 1, further comprising: The vehicle seat frame according to claim 1 or 2, further comprising a spiral spring arranged coaxially with the recliner and biasing the rear of the cushion frame in the direction in which the seatback frame stands up. The vehicle seat frame according to claim 1 or 2, in which the rear portion of the cushion frame and the seat back frame are integrally connected. A seat cushion on which an occupant sits;
A seat back that supports the back of an occupant;
Equipped with
A vehicle seat, wherein a framework of the seat cushion and the seat back is formed by the vehicle seat frame according to claim 1 or 2.