JPH0710599Y2 - Lumbar support device for middle back seat back - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a lumbar support device for a center-folded seat back applied to a vehicle seat or the like.

(Prior Art) According to Japanese Utility Model Publication No. 57-11580, an upper seat back is hinged to an upper end of a lower seat back hinged to a rear end of a seat cushion, and the lower seat is slid forward. The back is tilted backwards,
A center-folded seat back in which the upper seat back is in a slightly upright posture relative to the lower seat back is known.

(Problems to be Solved by the Invention) In the above-described prior art, the seat back is folded inward to fit the bending state of the back of the seated person by sliding the seat cushion forward. Is likely to sink into the lower seat back in a tilted posture,
It is desired to provide a lumbar support device that can give a support feeling to the waist.

By the way, conventionally, according to Japanese Utility Model Publication No. 1-31087, a lumbar support frame extending downward from the upper seatback frame is provided in a middle-folded seatback that allows the upper seatback to be tilted backward with respect to the lower seatback. A lumbar support device is known in which the lower free end of the lumbar support frame is swung forward when the upper seat back is tilted backward. It is conceivable to use this device for the center folding seat back described above. However, since the upper seat back leans forward with respect to the lower seat back due to the backward tilt of the lower seat back, the free end of the lumbar support frame is swung backward due to the backward tilt of the lower seat back, and the lumbar support feeling is felt. Can't get

The present invention has been made in view of the above points, and an object thereof is to provide a lumbar support device capable of providing a lumbar support feeling when the upper seat back is tilted forward with respect to the lower seat back.

(Means for Solving the Problems) In order to achieve the above object, in the present invention, a lower seat back hinged to a rear end of a seat cushion and an upper seat back hinged to an upper end of the lower seat back. In the one in which a lumbar support frame is provided in the center-folded seat back constituted by, the lumbar support frame is extended between the seat back frames through the lower member of the upper seat back frame and the front surface of the upper member of the lower seat back frame. The lumbar support frame is connected to the upper seat back frame at its upper end, and the lower end of the lumbar support frame is connected to the lower end of the lower seat back frame or the rear end of the seat cushion.

(Operation) When the upper seat back leans forward with respect to the lower seat back, the connecting portion of the upper end of the lumbar support frame to the upper seat back frame moves forward, and the lumbar support frame attaches to the lower seat back frame or seat cushion at its lower end. The lumbar support frame moves closer to the front surface of the lower seat back with the connecting point serving as a fulcrum, and the lumbar support feeling can be obtained.

(Embodiment) In the illustrated embodiment, the present invention is applied to a rear seat of a vehicle. (1) shows a seat cushion, (2) shows a seat back, and the seat cushion (1) is a floor panel (3) of a vehicle body. It was mounted on the upper rail (4) slidably in the front-back direction. The seat back (2) is composed of a center-folded seat back including a lower seat back (5) and an upper seat back (6) which are divided into upper and lower parts, and a lower end of the lower seat back frame (5a) and a cushion frame. (1a)
A hinge bracket (7) is fixed to each of the rear ends of the seat cushion (1) and the lower seat back (5) is hinged to the rear end of the seat cushion (1). Hinge brackets (8) are fixed to the lower ends of the frames (6a), and the upper seat back (6) is hinged to the upper end of the lower seat back (5).

Guide plates (9) having a pair of upper and lower arc-shaped elongated holes (9a) (9a) formed on both sides of the upper seatback frame (6a).
And a fixed pair of pins (11a) (11a) fixed to a bracket (11) attached to a back panel (10) of the vehicle body.
a) is engaged with each of the long holes (9a) (9a) to support the upper seat back (6) so that it can move up and down with respect to the back panel (10) in a predetermined locus, and thus the seat cushion. When (1) is slid forward, the lower seat back (5) tilts backward with the hinge point A to the seat cushion (1) as a fulcrum, as shown by the phantom line in FIG. The upper seat back (6) whose movement locus is restricted by the hole (9a) stands upright with respect to the lower seat back (5) with the hinge points B of both seat backs (5) and (6) as fulcrums. The seat back (2) was bent in the middle.

A lumbar support frame (12) is provided in the seat back (2). To describe this in detail, the lumbar support frame (12) is composed of a wire frame bent in a substantially V shape in a front view. , Extending between the seat back frames (5a) (6a) through the front side of the upper member (5b) of the lower seat back frame (5a) and the lower member (6b) of the upper seat back frame (6a). , Engaging the bent portion (12a) of the upper end of the lumbar support frame (12) with the vertically elongated hole (9a) formed in the guide plate (9), and the lower end of the lumbar support frame (12) On the side rod (12b) of the, flanges (13a) on both ends as shown in FIG.
A collar (13) having a C-shaped cross section is attached, and the lateral rod (12b) is fixed to the lower member (5c) of the lower seat back frame (5a) at the collar (13). 14) and the lumbar support frame (1) facing the waist of a seated person slightly above the side bar (12b).
The support plate (12c) was attached to part 2). still,
The frame (12) is formed so that the mounting portion of the support plate (12c) bulges forward, but it can be formed in any desired shape in consideration of the supportability of the waist.

Next, the operation of this embodiment will be described. When the seat back (2) is folded in the middle as described above by sliding the seat cushion (1) forward, the upper seat back (6) is in a lower tilted lower seat back. The connecting point C of the lumbar support frame (12), which is tilted forward with respect to (5) and is located above the hinge point B of the upper seat back (6) with respect to the lower seat back (5), with respect to the upper seat back frame (6a). The lumbar support frame (12) moves forward with respect to the connection between the hinge point B and the lower hinge point A, and the lumbar support frame (12) is connected to the lower seatback frame (5a) by using the connection point D composed of the hook (14) as a fulcrum. Inclining forward with respect to the lower seat back frame (5a),
c) approaches the front of the lower seat back (5).

In this case, since the connection point D which is the tilt fulcrum of the lumbar support frame (12) and the hinge point B which is the tilt fulcrum of the upper seat back (6) are apart from each other, the lower seat back (5) of the upper seat back (6) is When leaning forward against
The position of the connection point C is displaced upward with respect to the upper seat back frame (6a), and the bent portion (12a) at the upper end of the lumbar support frame (12) is provided with the long hole (as described above) to allow this displacement. 9a), but the connection point C is immovable with respect to the upper seat back frame (6a), and the connection point D at the lower end of the lumbar support frame (12) is slidable in the vertical direction. Is also possible. Furthermore, connect both connecting points C and D to each seat back frame (5a).
It is also possible to make it immovable with respect to (6a). In this case, the lumbar support frame (12) can be made to extend and contract in the vertical direction, or the lumbar support frame (12) can be bent forward by buckling. .

In the above embodiment, the lumbar support frame (12)
Although the lower end of the seat cushion is connected to the lower end of the lower seat back frame (5a), the same effect can be obtained by connecting it to the rear end of the seat cushion (1). Further, the present invention is not limited to the vehicle rear seats as in the above embodiment, but can be applied to front seats and seats other than those for vehicles.

(Effect of the Invention) As is apparent from the above description, according to the present invention, the lumbar support frame approaches the front surface of the lower seat back due to the forward inclination of the upper seat back with respect to the lower seat back, and the lumbar support during reclining. It has the effect of obtaining a good feeling.

[Brief description of drawings]

FIG. 1 is a perspective view of an example of the device of the present invention, FIG. 2 is a side view for explaining its operation, and FIG. 3 is an enlarged sectional view taken along line III-III of FIG. (1) …… seat cushion (2) …… seat back (5) …… lower seat back (5a) …… lower seat back frame (6) …… upper seat back (6a) …… upper seat back frame (12) ) …… Lumber support frame

Claims (1)

[Scope of utility model registration request] 1. A lumbar support frame is provided in a center-folded seat back which is composed of a lower seat back hinged to a rear end of a seat cushion and an upper seat back hinged to an upper end of the lower seat back. The lumbar support frame is extended between the seatback frames through the front side of the lower member of the upper seatback frame and the upper member of the lower seatback frame, and the upper end of the lumbar support frame is connected to the upper seatback frame. A lumbar support device for a middle-folded seat back, characterized in that the lower end of the lumbar support frame is connected to the lower end of the lower seat back frame or the rear end of the seat cushion.