JPH11192869A - Seat back for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain the amount of operation of a head rest sufficiently even when it is applied to a seat back frame less in lateral width and height dimensions. SOLUTION: An upper end part 16a of a second link 16 in which a lower end part 16b is supported movably on both side end part of a seat back frame 2 is pivoted rotatably on an operating link 7 generally at a middle position 7c between a front end part 7a and a rear end part 7b for suspension. Then a pressure receiving member 21 pressed against the back of a driver is supported by the second link 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle seat back, and more particularly to a vehicle seat back structure for protecting a passenger's cervical spine during a rear-end collision.

[0002]

2. Description of the Related Art As a conventional seat back of an automobile, Japanese Patent Application Laid-Open No. Hei 7-291005, particularly, as shown in the second embodiment, for example, when the automobile is hit by a rear impact, the seat is subjected to an impact toward the front side. As a result, the load of the occupant acts on the S-spring installed between the seat back frames toward the rear side. At this time, since a load equal to or more than a predetermined value is applied to the connecting members located at both ends of the S spring, the connecting members extend rearward, and it is possible to prevent the occupant's entire body from leaning backward to some extent. In addition, when the upper connecting member extends rearward, the headrest support arm rotates around the upper side of the seat back frame as a rotation fulcrum, and the headrest supported at the upper end thereof approaches the occupant's head. To move.

[0003] Therefore, when the vehicle is collided, the occupant is prevented from being lifted to the rear of the vehicle diagonally upward, and the headrest approaches the occupant's head instantly, so that the occupant's head is reliably received by the headrest. Thus, the occupant's neck is protected.

[0004]

However, in such a conventional technique, when such a conventional technique is applied to a seat back frame having a small lateral width and a small height, the upper body of the occupant is located on the rear side. Therefore, the amount of the upper body itself interfering with the seat back frame and pushing the connecting member backward is small, so that the amount of operation of the headrest is small, and improvement is required.

The present invention has been made by paying attention to such a conventional technique, and a vehicle seat capable of sufficiently securing the operation amount of a headrest even when applied to a seatback frame having a small lateral width and height. Is to provide the back.

[0006]

According to a first aspect of the present invention, there is provided a seatback frame, a headrest having a stay pivotally supported on an upper end portion of the seatback frame so as to be able to rotate back and forth, and a headrest. A pressure receiving member extending left and right at a position below the stay and receiving pressure on the back of the occupant; a front end rotatably supported at both side ends of the seat back frame; A vehicle seat back comprising an operation link rotatably supported by the stay, wherein a lower end of the seat is located substantially at an intermediate position between a front end and a rear end of the operation link. The upper end of a second link supported movably at both ends of the back frame is suspended by being rotatably supported by a shaft, and the pressure receiving member is supported by the second link. To And butterflies.

According to a second aspect of the present invention, there is provided the vehicle seat back according to the first aspect, wherein the floating support portion of the second link to the seat back frame extends linearly along the vertical direction. It is characterized by being formed.

According to a third aspect of the present invention, there is provided the vehicle seat back according to the first aspect, wherein a floating support portion of the second link to the seat back frame is provided such that the second link is provided on a lower side. It is characterized by being formed in an arc shape for moving the second link toward the front side as it moves.

According to a fourth aspect of the present invention, there is provided the vehicle seat back according to the first aspect, wherein the floating support portion of the second link to the seat back frame extends vertically and has a lower end on the front side. It is characterized by being formed in the shape of a long hole that is curved.

According to a fifth aspect of the present invention, there is provided a seatback frame, a headrest having a stay pivotally supported on an upper end of the seatback frame so as to be able to rotate back and forth, and a headrest below the stay of the headrest. A pressure receiving member extending left and right at a position and receiving pressure on the back of the occupant; a front end rotatably supported at both side ends of the seat back frame; and a rear end rotatably supported by the stay. A vehicle seatback comprising at least a pivotally supported operation link and a seatback cushion disposed on the front side of the pressure receiving member, wherein a front end and a rear end of the operation link are substantially defined. At an intermediate position, the upper end of a second link, the lower end of which is rotatably supported on both side ends of the seat back frame, is pivotally supported movably, and the pressure receiving member is Characterized by comprising supported by the second link.

According to a sixth aspect of the present invention, there is provided the vehicle seat back according to the fifth aspect, wherein the floating support portion of the second link at a substantially intermediate position of the operation link has a substantially linear longitudinal direction. And the center line in the longitudinal direction of the floating support portion is formed such that the rotation support portion to the seat back frame substantially coincides with the extension line below the center line. And

According to a seventh aspect of the present invention, there is provided the vehicle seat back according to the fifth aspect, wherein the floating support portion of the second link at a substantially intermediate position of the operation link has a substantially linear longitudinal direction. And the center line in the longitudinal direction of the floating support portion is formed such that the rotation support portion to the seat back frame is displaced from the extension line below the center line. It is characterized by the following.

According to an eighth aspect of the present invention, there is provided the vehicle seat back according to the seventh aspect, wherein a center line in the longitudinal direction of the floating support portion is an extension line below the center line, and It is characterized by being located behind the rotation support portion to the back frame.

According to a ninth aspect of the present invention, there is provided the vehicle seat back according to the fifth aspect, wherein the floating support portion of the second link at a substantially middle position of the operating link has a substantially arc shape in a longitudinal direction. It is characterized by comprising a long hole forming the following.

According to a tenth aspect of the present invention, in the vehicle seat back according to the ninth aspect, the arcuate shape of the floating support portion in the longitudinal direction is curved forward.

According to an eleventh aspect of the present invention, there is provided the vehicle seat back according to the fifth aspect, wherein the floating support portion of the second link at a substantially intermediate position of the operating link has a substantially linear longitudinal direction. And the center line in the longitudinal direction of the floating support portion is formed so that the rotation support portion to the seat back frame substantially coincides with the extension line below the center line, and the operation is performed. A rotation support portion for supporting the seat back frame from a shaft support portion at a substantially intermediate position of the link is disposed rearward.

According to a twelfth aspect of the present invention, there is provided the vehicle seat back according to the fifth aspect, wherein the floating support portion of the second link at a substantially intermediate position of the operating link has a substantially linear longitudinal direction. The floating center portion of the floating support portion has a center line in the longitudinal direction, and a rotating shaft supporting portion of the front end of the operating link to the seatback frame and a shaft supporting portion disposed at a substantially intermediate position of the operating link. Are formed so as to substantially coincide with each other.

According to a thirteenth aspect of the present invention, there is provided the vehicle seat back according to the fifth aspect, wherein the floating support portion of the second link at a substantially intermediate position of the operation link has a substantially linear longitudinal direction. And the center line in the longitudinal direction of the floating support portion is formed so that the rotation support portion to the seat back frame substantially coincides with the extension line below the center line, and the operation is performed. A rotation shaft supporting portion of the front end portion of the link to the seat back frame and a shaft supporting portion arranged at a substantially intermediate position of the operation link are formed so as to substantially coincide with each other,
Further, a rotation support portion for supporting the seat back frame from a pivot portion at a substantially intermediate position of the operation link is disposed on a front side.

[0019]

According to the first aspect of the present invention, the pressure receiving member is supported by the second link, and the second link is supported at a substantially intermediate position between the front end and the rear end of the operating link. Therefore, the second link largely moves the operation link even with a small amount of movement of the pressure receiving member, so that the operation amount of the headrest can be sufficiently secured even when applied to a seatback frame having a small lateral width and a small height.

According to the second aspect of the present invention, since the amount of movement of the second link in the front-rear direction can be reduced, the thickness of the seat back in the front-rear direction does not increase.

According to the third aspect of the present invention, the pressure receiving member rotates substantially parallel to the rotation locus as compared with the case where the floating support portion of the second link is formed in a linear shape. Is formed on a surface, a load can be received over substantially the entire surface regardless of the movement of the pressure receiving member.

According to the fourth aspect of the invention, the rotation angle of the pressure receiving member can be reduced and the amount of movement of the second link in the front-rear direction can be reduced.

According to the fifth aspect of the present invention, the pressure receiving member is supported by the second link, and the lower end of the second link is rotatably supported by both side ends of the seat back frame. Since the upper end is pivotally supported at a substantially intermediate position between the front end and the rear end of the operation link, the second link largely moves the operation link even with a small amount of movement of the pressure receiving member, so that the lateral width and the height can be increased. Even when the present invention is applied to a seat back frame having a small number of headrests, the operation amount of the headrest can be sufficiently secured.

When the second link rotates about the lower end, the upper end of the second link rotates rearward, so that the rear end of the operating link moves upward, and the headrest is fully operated. Although the amount is secured, the pressure receiving member moves in a direction away from the seat back cushion, so that operation inhibition of the pressure receiving member does not occur.

According to the sixth aspect of the present invention, the center line in the longitudinal direction of the elongated hole, which is the floating support portion, and the rotation support portion to the seat back frame substantially match, so that the second link rotates. Then, the shaft support of the operation link can smoothly move so as to contact one of the long holes of the second link.

According to the seventh aspect of the present invention, since the center line in the longitudinal direction of the elongated hole serving as the floating support portion and the rotary support portion to the seat back frame are shifted from each other,
When the second link rotates, one wall of the long hole of the second link is pressed by the shaft support at a substantially intermediate position of the operation link, so that rotation with a small force is possible.

According to the eighth aspect of the present invention, the angle between the initial movement direction at the substantially middle position of the operation link and the center line in the longitudinal direction of the floating support portion is close to a right angle. , With less force.

According to the ninth aspect of the present invention, the angle formed between the initial movement direction at the substantially intermediate position of the operation link and the longitudinal center line of the floating support portion is close to a right angle. , With less force.

According to the tenth aspect of the present invention, when the second link rotates, one wall of the elongated hole of the second link is pressed by the shaft support at a substantially intermediate position of the operating link.
Rotation with a small force becomes possible.

According to the eleventh aspect of the present invention, the center line in the longitudinal direction of the elongated hole, which is the floating support portion, substantially coincides with the rotation support portion to the seat back frame, and the rotation support portion is Since the second link is rotated about the rotation support portion, the initial movement direction of the substantially intermediate position of the operation link and the longitudinal direction of the floating support portion are arranged when the second link rotates about the rotation support portion. Since the angle between the direction and the center line is close to a right angle, the rotation of the working link can be started with a smaller force.

According to the twelfth aspect of the present invention, the direction in which the elongated hole of the floating support portion pushes the shaft support of the operating link substantially coincides with the initial movement direction of the shaft support. It is possible to start rotation with force.

According to the thirteenth aspect of the present invention, the direction in which the elongated hole of the floating support presses the shaft support of the operating link substantially coincides with the initial movement direction of the shaft support. It is possible to start rotation with force.

[0033]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. Note that FR is described as a front side, RR is a rear side, UP is an upper side, and DW is a lower side.

FIGS. 1 to 3 show a first embodiment of the present invention. A seat back 1 of an automobile comprises a seat back frame 2 and a headrest 3.

The seat back frame 2 has an upper end 2a.
And side SWs 2b, 2b hanging from the left and right ends of the upper end 2a, and welding SW at the lower ends of the side ends 2b, 2b.
And an underframe 2c fixedly provided.

The first bracket 5 supported on the side plates 4, 4 fixed to the side ends 2b, 2b has
The operating links 7, 7 are moved up and down by the first pin 6,
It is rotatably supported in the direction. The portions of the operating links 7, 7 on which the first pins 6 are pivotally supported are front end portions 7a.

The lower end 8a of the support arm 8 is vertically moved to the rear end 7b of the operating
It is rotatably supported in the W direction.

A first rod 10 extending substantially horizontally to the left and right is connected to upper ends 8b of the support arms 8, 8.
It is provided between the support arms 8 and 8.

An inverted U-shaped movable stay 11 disposed in the headrest 3 is provided at an intermediate portion of the first rod 10.
The lower end portion 12a of the fixed stay 12 which is movable in the up and down UP and DW directions and can be held at an appropriate position is fixedly provided by welding GW.

The movable stay 11 and the fixed stay 12
Thus, the stay 13 is formed.

The upper end 2a of the seat back frame 2
, The second bracket 15 is supported by the bolt and nut 14, and the holding portion 28 of the second bracket 15 supports the fixed stay 12 of the stay 13 so as to be movable to the front side FR and the rear side RR. .

The front end 7a and the rear end 7 of the operating link 7
A third pin 17 is pivotally supported by an upper end 16a of the second link 16 on a support portion 7c formed near a front end portion 7a from a substantially intermediate position with respect to the front end portion 7a. It is suspended by being rotatably supported on the rear side RR.

At the lower end 16b of the second link 16,
A fourth slot 18 is formed in the up-down direction as a "moving support part", and is formed in the long slot 18 on both side ends 2b, 2b of the seat back frame 2 via a third bracket 20. A pin 19 is slidably connected to the second link 16, and the second link 16 is supported movably in a vertical direction.

The elongated hole 18 is formed in an arc shape for moving the second link 16 toward the front side FR as the second link 16 moves downward.

Reference numeral 21 denotes a plate as a "pressure receiving member", which is supported near the lower end 16b of the second link 16.

Reference numeral 22 denotes a second rod extending between the upper end portions 16a of the second link 16 and the second rod 16.
The left and right second links 16, 16 are supported by the rod 22 so as to be able to move together.

Reference numeral 23 denotes an S-shaped spring which is stretched between the fourth brackets 24, 24 projecting from the second link 16 and between the fifth brackets 25, 25 projecting from the side plate 4.

Reference numeral 26 denotes a seat back cushion which incorporates these components except the headrest 3 and has a cushioning property (not shown).

Next, the headrest 3 according to this embodiment will be described.
The operation of will be described.

First, since the support arms 8 have a relationship of being moved by the moving force of the plate 21,
When the occupant's upper body moves to the rear side RR, the occupant's back causes the S-shaped spring 23, particularly the S-shaped spring 23 supported between the fourth brackets 24, 24 to bend rearward. S-shaped spring 23 bent back
Thereby, the plate 21 is pushed to the rear side RR.

Since the second link 16 supporting the plate 21 urges the operating link 7 through the third pin 17 located near the front end 7a, the operating link 7 is
The first pin 6 is rotated in the upper UP and lower DW directions.

Accordingly, when the operating link 7 rotates upward, the upper ends 8b, 8b of the support arms 8, 8 move upward.
In addition, since the lower end portion 12a of the fixed stay 12 of the headrest 3 is also moved to the upper side UP and the rear side RR by the movement, the movable stay 11 side around the holding portion 28 is moved to the upper side UP and the front side. As shown in FIG. 3, the headrest 3 moved to the FR and supported by the movable stay 11 moves to the front side FR by the dimension A and moves to the upper side by the dimension B to hold the head of the occupant. Will do. At this time, the third pin 17 located near the front end 7a
Since the second link 16 connected to the operating link 7 is interposed in FIG. 3, the movement amount L between the position of the plate 21 shown by the two-dot chain line and the position of the plate 21 shown by the solid line in FIG. It is possible to move the headrest 3 more reliably even if the operating link 7 is shorter.

The second link 16 and the second link 1
The configuration of the floating support portion 6 is not limited to the above-described embodiment. For example, as shown in FIG. 4 showing only the second link and the main portion of the floating support portion of the second link, It may be a long hole 18 ′ as a linear “engaging portion” along the direction, in which case the plate 21
With the movement of 6 ′, the inclination of the surface also changes relatively largely as shown by the dashed line in FIG.
The amount of movement of the lower end of the seat back in the front-rear direction can be reduced, so that the thickness of the seat back 1 in the front-rear direction does not increase.
Reference numerals 16'a and 16'b are the upper end and the lower end of the second link 16 ', and the same reference numerals are used for other portions that are the same as those in the above-described embodiment.

Further, as shown in FIG. 5, which similarly shows only the main part, the floating support is connected to the upper end 1 of the second link 16 ''.
3rd pin 17 which is a connecting portion between 6 ″ a and the operating link 7
May be an elongated hole 18 ″ as an “engaging portion” on the side plate 4 side along the rotation locus of the side plate. In this case, since the inclination of the surface due to the movement of the plate 21 is small, the load is However, the amount of forward and backward movement of the lower end 16 ″ b of the second link 16 ″ increases.

In the embodiment of FIGS. 1 to 4 described above, the long holes 18, 18 'are formed in the second links 16, 16'. However, as in the embodiment shown in FIG. Alternatively, the slot 18 may be formed on the side of the side plate 4 in the embodiment shown in FIG. 5, but in the embodiment shown in FIG. As long as there is room, it may be formed on the second link 16 ″ side as in the embodiment shown in FIG. 2 to FIG. 4, and both have the same function.

FIGS. 6 to 8 show a second embodiment of the present invention. The same members as those shown in FIGS. 1 to 4 are denoted by the same reference numerals and description thereof is omitted.

Both ends of the plate 21 as a “pressure receiving member” are supported by the second links 30, 30. The S-shaped spring 23 is stretched and a seat back cushion 26 made of a cushioning material such as polyurethane foam which constitutes the seat back 1 is disposed at a position separated from the front side of the plate 21.

The lower end 30a of the second link 30 is rotatably supported by both ends 2b, 2b of the seat back frame 2 by a fifth pin 31 as a "rotation support portion for the seat back frame". It becomes. An upper end portion 30b of the second link 30 is pivotally supported at a substantially intermediate position 7c between the front end portion 7a and the rear end portion 7b of the operation link 7 by a fourth pin 32 as a "shaft supporting portion". .

The upper end 30b of the second link 30 to the support 7c formed at a substantially intermediate position of the operation link 7 has
An elongated hole 33 is formed as a "moving support portion" whose longitudinal direction is substantially linear. The elongated hole 33 is formed such that the center line 34 in the longitudinal direction is substantially aligned with the fifth pin 31 to the seat back frame 2 on the lower extension 34a of the center line 34.

Next, the headrest 3 according to this embodiment will be described.
The operation of will be described.

First, a sudden load such as a collision is applied to the occupant seated on the seat, and the upper body of the occupant is moved to the rear side RR by the secondary collision load. Spring 23, especially fourth bracket 2
S-shaped spring 2 supported between 4, 24 (see FIG. 1)
3 will bend back. The plate 21 is pushed to the rear side RR by the S-shaped spring 23 bent backward.

The second link 30 supporting the plate 21 is urged to rotate about the fifth pin 31 in the direction of arrow C in FIG. It moves while sliding upward in the hole 33. Working link 7
8 is rotationally urged about the first pin 6 in the direction of arrow D in FIG. 8, and the operation link 7 is rotated about the first pin 6 on the second pin 9 side in the upward UP direction.

Therefore, as shown in FIG. 7, when the second pin 9 side of the operation link 7 shown by the two-dot chain line is rotated to the position shown by the solid line, that is, to the upper side UP, the upper ends 8 of the support arms 8, 8 are rotated.
b and 8b move to the upper side UP and the rear side RR. By this movement, the lower end portion 12a of the fixed stay 12 of the headrest 3 is also moved to the upper side UP and the rear side RR, so that the movable stay 11 side is moved to the upper side UP and the front side FR centering on the holding portion 28, and the movable stay As shown in FIG. 7, the headrest 3 supported by 11 moves to the front side FR by the dimension A and moves to the upper side UP by the dimension B, thereby holding the occupant's head.

At this time, since the second link 30 connected to the operating link 7 is interposed by the fourth pin 32 located near the front end 7a of the operating link 7, it is shown by a two-dot chain line in FIG. The position of the plate 21 and the plate 21 indicated by a solid line
Is smaller than before, and the headrest 3 can be reliably moved even if the operating link 7 is short.

Further, since the plate 21 does not move upward, there is no obstruction of operation due to a vertical frictional force between the plate 21 and the back cushion 26. Accordingly, the operation of the operation link 7 and the second link 30 is performed, and
As a result, the headrest 3 is surely in the front FR and upper UP
You can move to

FIG. 9 shows a third embodiment of the present invention, in which the same members as those described in FIGS.
Only the reference numerals are used, and the description is omitted as much as possible.

The main difference between the third embodiment and the second embodiment is that the second link 30 of the second embodiment is substantially linear while the second link 30 of the second embodiment is substantially linear. 35
Is bent substantially to the front side FR at a bent portion 35a near the lower end of the elongated hole 33.

Next, the operation according to this embodiment will be described.

The initial movement direction of the fourth pin 32 formed at a substantially intermediate position of the operation link 7 (that is, the operation link 7
Since the angle Θ2 between the initial rotation direction B) of the second link 35 and the center line 34 in the longitudinal direction of the long hole 33 as the “floating support portion” is closer to the right angle than the angle Θ1 shown in FIG.
The operation start is easier than in the second embodiment.

FIG. 10 shows a fourth embodiment of the present invention. The same members as those described in FIGS. 6 to 8 are denoted by the same reference numerals, and description thereof is omitted.

The main difference between the fourth embodiment and the third embodiment is that the elongated hole 33 of the second link 35 of the third embodiment is substantially straight, whereas the fourth embodiment is different from the third embodiment. Second form
The link 36 is formed such that the longitudinal direction of the long hole 37 as the “floating support portion” is formed in a curved shape centering on the front side FR. In the vicinity of the lower end of the elongated hole 37 of the second link 36, similarly to the second link 35, a bent portion 36 a bent substantially to the front side FR is provided.

Next, the operation according to this embodiment will be described.

The initial movement direction of the fourth pin 32 formed at a substantially intermediate position of the operation link 7 (that is, the operation link 7
Since the angle） 3 between the initial rotation direction B of the second link 36 and the center line 34 of the arc of the elongated hole 37 as the “floating support portion” of the second link 36 is closer to the right angle than the angle Θ1 shown in FIG. Start is easier than in the second embodiment.

That is, when the second link 36 rotates, one wall of the elongated hole 37 of the second link 36 is pressed by the fourth pin 32 of the operating link 7, so that rotation with a small force is possible. .

FIG. 11 shows a fifth embodiment of the present invention. The same members as those described in FIGS. 6 to 8 are denoted by the same reference numerals, and description thereof is omitted.

The main difference between the fifth embodiment and the second embodiment is that the rotation support portion 31 of the second link 30 to the seat back frame 2 of the second embodiment is on the front side. On the other hand, a fifth pin 38 as a rotation support portion of the second link 30 to the seat back frame 2 of the fifth embodiment is disposed on the rear side.

That is, the elongated hole 33 as the “free-moving support portion” of the second link 30 to the fourth pin 32 at a substantially intermediate position of the operating link 7 has a substantially linear shape in the longitudinal direction as described above. The center line 34 in the longitudinal direction of the long hole 33 is
4 on the lower extension line 34a.
A fifth pin 38 serving as a rotation support portion is formed so as to substantially coincide with the fourth pin 3 of the operating link 7.
2, a fifth pin 38 serving as a rotation support portion for the seat back frame 2 is disposed on the rear side RR.

Next, the operation according to this embodiment will be described.

The longitudinal center line 34 of the elongated hole 33 and the fifth
The second link 30 is indicated by an arrow C around the fifth pin 38 since the pin 38 substantially matches the pin 38 and the fifth pin 38 is disposed on the rear side RR of the operating link 7 behind the fourth pin 32. When the rotation is performed in this manner, the angle Θ4 between the initial movement direction B of the fourth pin 32 of the operation link 7 and the center line 34 in the longitudinal direction of the elongated hole 33 is close to a right angle. It is possible with a small force.

FIG. 12 shows a sixth embodiment of the present invention. The same members as those described in FIGS. 6 to 8 are denoted by the same reference numerals, and description thereof is omitted.

The main difference between the sixth embodiment and the third embodiment is that the first operation link 7 of the third embodiment is different from the first embodiment.
While the position of the pin 6 and the elongated hole 33 of the second link 35 are not related at all, the position of the first pin 39 of the operating link 7 of the sixth embodiment is different from that of the second link 35. That is, it is arranged at a position substantially coincident with the center line 34 of the elongated hole 33.

That is, the elongated hole 33 of the second link 35 to the fourth pin 32 of the operating link 7 has a substantially linear elongated hole shape in the longitudinal direction, and the longitudinal center line 34 of the elongated hole 33 is A first pin 39 serving as a “rotating shaft support” at the front end of the operation link 7 to the seat back frame 2, and a fourth pin 32 serving as a “shaft support” disposed substantially at an intermediate position of the operation link 7. Are formed so as to substantially match with each other.

Next, the operation according to this embodiment will be described.

Since the direction B in which the elongated hole 33 pushes the fourth pin 32 of the operation link 7 substantially coincides with the initial movement direction E of the fourth pin 32, the operation link 7 starts rotating with a smaller force. Is possible.

FIG. 13 shows a seventh embodiment of the present invention. The same members as those described in FIGS. 6 to 8 are denoted by the same reference numerals, and description thereof is omitted.

The main difference between the seventh embodiment and the second embodiment is that the first operation link 7 of the second embodiment is different from the first embodiment.
While the position of the pin 6 and the elongated hole 33 of the second link 30 are not related at all, the position of the first pin 39 of the operating link 7 of the seventh embodiment is different from the position of the second link 30. That is, it is arranged at a position substantially coincident with the center line 34 of the elongated hole 33.

That is, the elongated hole 33 as a floating support portion of the second link 30 to the fourth pin 32 at a substantially intermediate position of the operating link 7 has a substantially linear elongated hole shape in the longitudinal direction. The center line 34 in the longitudinal direction of 33 is formed such that the fifth pin 31 as a “rotation support portion” to the seat back frame 2 substantially coincides with the lower extension line 34 a of the center line 34. In addition, a first pin 39 as a “rotating shaft support” at the front end of the operation link 7 to the seat back frame 2 is formed so as to substantially coincide with a fourth pin 32 of the operation link 7. Fifth pin 3 from fourth pin 32 of actuation link 7 to seatback frame 2
1 is arranged on the front FR.

Next, the operation according to this embodiment will be described.

Since the direction B in which the elongated hole 33 pushes the fourth pin 32 of the operation link 7 substantially coincides with the initial movement direction E of the fourth pin 32, the operation link 7 starts rotating with a smaller force. Is possible.

When the second link 30 rotates in the direction of arrow C about the fifth pin 31, the initial movement direction B of the fourth pin 32 of the operating link 7 and the longitudinal center line 34 of the elongated hole 33 Since the angle Θ5 formed is close to a right angle, the operating link 7
Can be started with a smaller force.

[Brief description of the drawings]

FIG. 1 is a front view showing a seat back according to a first embodiment of the present invention.

FIG. 2 is a side view of FIG. 1;

FIG. 3 is an operation explanatory view of the seat back of FIG. 2;

FIG. 4 is a side view of a main part according to another example of the first embodiment.

FIG. 5 is an essential part side view according to still another example of the first embodiment.

FIG. 6 is a side view corresponding to FIG. 2 according to a second embodiment of the present invention.

FIG. 7 is an operation explanatory view of FIG. 6;

FIG. 8 is a side view of a main part of FIG. 7;

FIG. 9 is a side view of a main part according to a third embodiment of the present invention.

FIG. 10 is a main part side view according to a fourth embodiment of the present invention.

FIG. 11 is a side view of a main part according to a fifth embodiment of the present invention.

FIG. 12 is a side view of a main part according to a sixth embodiment of the present invention.

FIG. 13 is a side view of a main part according to a seventh embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Seat back 2 Seat back frame 2a Upper end of seat back frame 2b Side end of seat back frame 3 Headrest 7 Actuation link 7a Front end of actuation link 7b Rear end of actuation link 7c Supporting part of intermediate part of actuation link 8 Support arm 8a Lower end 12a Lower end of fixed stay corresponding to lower end of stay 13 Stay 16, 16 ', 16 "Second link 16a, 16'a, 16" a Upper end 16b, 16 of second link 'b, 16''b Lower end portion of second link 18, 33, 37 Long hole 18' as a floating support portion 18 ', 18''Long hole as an engagement portion 21 Plate as pressure receiving member 26 Seat back cushion 30, 35, 36 Second link 31, 38 Fifth pin 32 as a rotation support part to seat back frame Fourth pin 34 as a shaft support part 34 Length Center line 39 first pin FR front RR behind the

Claims (13)

[Claims] 1. A seat back frame, a headrest having a stay pivotally supported on an upper end portion of the seat back frame so as to be able to rotate back and forth, and extending left and right at a position below the stay of the headrest. A pressure receiving member for receiving pressure on the back of the occupant; and an operating link having a front end rotatably supported on both side ends of the seat back frame and a rear end rotatably supported by the stay. A vehicle seat back comprising: a substantially intermediate position between a front end and a rear end of the operating link;
An upper end portion of a second link, whose lower end portion is freely movably supported by both end portions of the seat back frame, is suspended by being rotatably supported by a shaft, and the pressure receiving member is attached to the second link by the second link. A vehicle seat back characterized by being supported. 2. The vehicle seat back according to claim 1, wherein the floating support portion of the second link to the seat back frame is formed linearly along the up-down direction. Vehicle seat back. 3. The vehicle seat back according to claim 1, wherein the floating support portion of the second link to the seat back frame moves forward as the second link moves downward. A vehicle seat back formed in an arc shape for moving a second link. 4. The vehicle seat back according to claim 1, wherein the floating support portion of the second link to the seat back frame has an elongated hole shape along a vertical direction and a lower end curved forward. A vehicle seat back characterized by being formed. 5. A seat back frame, a headrest having a stay pivotally supported on an upper end of the seat back frame so as to be able to rotate back and forth, and extending left and right at a position below the stay of the headrest. A pressure receiving member for receiving pressure on the back of the occupant; and an operating link having a front end rotatably supported on both side ends of the seat back frame and a rear end rotatably supported by the stay. And a seat back cushion arranged at least on a front side of the pressure receiving member, wherein the seat is substantially at an intermediate position between a front end and a rear end of the operating link.
An upper end of a second link, whose lower end is rotatably supported on both side ends of the seat back frame, is freely pivotally supported, and the pressure receiving member is supported by the second link. A seat back for a vehicle, comprising: 6. The vehicle seat back according to claim 5, wherein the floating support portion of the second link at a substantially intermediate position of the operation link comprises an elongated hole having a substantially straight line in a longitudinal direction. A seat back for a vehicle, wherein a center line in a longitudinal direction of the floating support portion is formed so as to substantially coincide with a rotation support portion to the seat back frame on an extension line below the center line. 7. The vehicle seat back according to claim 5, wherein the floating support portion of the second link at a substantially intermediate position of the operation link comprises an elongated hole having a substantially linear longitudinal direction. A vehicle wherein the longitudinal center line of the floating support portion is formed at a position where an extension line below the center line and a rotation support portion to the seat back frame are shifted. Seat back. 8. The vehicle seat back according to claim 7, wherein a center line in a longitudinal direction of the floating support portion is a lower extension of the center line, and a rotation support portion to the seat back frame. A vehicle seat back that is located further behind. 9. The vehicle seat back according to claim 5, wherein the floating support portion of the second link at a substantially intermediate position of the operation link is a long hole having a substantially arc shape in a longitudinal direction. A vehicle seat back characterized by the following. 10. The vehicle seat back according to claim 9, wherein the arcuate shape of the floating support in the longitudinal direction is curved forward. 11. The vehicle seat back according to claim 5, wherein the floating support portion of the second link at a substantially intermediate position of the operation link comprises an elongated hole having a substantially linear longitudinal direction. A center line in a longitudinal direction of the floating support portion is formed so that a rotation support portion to the seat back frame substantially coincides with an extension line below the center line, and a shaft substantially at an intermediate position of the operation link. A seat back for a vehicle, wherein a rotation support portion for supporting the seat back frame from a support portion is disposed on a rear side. 12. The vehicle seat back according to claim 5, wherein the floating support portion of the second link at a substantially intermediate position of the operation link comprises an elongated hole having a substantially linear longitudinal direction. A center line in the longitudinal direction of the floating support portion is formed such that a rotation shaft support portion of the front end of the operation link to the seat back frame substantially coincides with a shaft support portion disposed at a substantially intermediate position of the operation link. A vehicle seat back characterized by being made. 13. The vehicle seat back according to claim 5, wherein the floating support portion of the second link at a substantially intermediate position of the operation link comprises an elongated hole having a substantially linear longitudinal direction. The center line in the longitudinal direction of the floating support portion is formed so that the rotation support portion to the seat back frame substantially coincides with an extension line below the center line, and the seat at the front end of the operating link is formed. The rotating shaft supporting portion to the back frame and the shaft supporting portion disposed substantially at the intermediate position of the operation link are formed so as to substantially coincide with each other, and further, the shaft supporting portion substantially at the intermediate position of the operating link is connected to the seat back frame. A seat back for a vehicle, wherein the rotation support portion is disposed on the front side.