JPH0937890A - Seat cushion length adjuster - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily arrange a seat cushion length adjuster, to simplify the structure and to enlarge the adjusting range of a seat cushion length. SOLUTION: The upper part of a seat back 20 is supported rockably around a first horizontal direction axial line O1 to the upper part of a seat back frame 10 raised upwards from the frame of a seat cushion C and a lower part is made to reach near the upper surface of the seat cushion. A crank member 30 supports the tip part of a crank arm part 30b to both side parts 12a of a seat back frame rotatably around a second horizontal direction axial line O2 and its eccentric part 30a is engaged to the rear side lower part of the seat back practically slidably in a vertical direction. The crank member is turned around the second horizontal direction axial line as a center by a driving mechanism 35, the eccentric part 30a of the crank member 30 is rocked, the lower part of the seat back is rocked in front and back directions with the first horizontal direction axial line as the center and the seat cushion length is adjusted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for adjusting the seat cushion length by changing the position of the seat cushion with respect to the seat back in a seat such as an automobile.

[0002]

A conventional seat cushion length adjusting device of this kind is disclosed in, for example, Japanese Utility Model Publication No. 1-2512.
As disclosed in Japanese Patent Publication No. 2-44581 or Japanese Utility Model Publication No. 2-44581, the seat cushion is moved in the front-rear direction with respect to the upper rail of the seat track by an adjusting mechanism such as a link mechanism provided on the lower side of the seat cushion and attached to the upper rail. The position of the seat cushion is changed relative to the seat back. However, if there is another adjusting mechanism such as a vertical position adjusting mechanism of the seat that needs to be provided below the seat cushion, there is a problem in that the seat cushion length adjusting device is difficult to arrange due to interference with the adjusting mechanism.

Further, the conventional seat cushion length adjusting device using a link mechanism or the like has a problem that the structure is apt to be complicated and it is difficult to increase the seat cushion length adjusting range. An object of the present invention is to solve each of these problems.

[0004]

In the seat cushion length adjusting device according to the present invention, one end of the seat cushion frame is attached to the frame of the seat cushion and the upper part of the seat back is placed above the seat back frame in the first lateral direction. A second lateral direction in which the base end of the crank arm portion of the crank member is substantially parallel to the first lateral axis so that the lower portion reaches the vicinity of the upper surface of the seat cushion so as to be swingable around the axis. An eccentric part that is rotatably supported around both sides of the seat back frame and that is provided at the tip of the crank arm in parallel with the second lateral axis is provided in the lower rear part of the seat back substantially only in the vertical direction. Engage slidably. Then, the crank member is rotated about the second lateral axis by the drive mechanism to swing the eccentric portion of the crank member, and the lower portion of the seat back is moved about the first lateral axis located above. Adjust the seat cushion length by rocking in the front-back direction.

The crank member includes an eccentric portion, crank arms at both ends, a winding portion formed at the tip of one crank arm, a drive arm portion further extending from the winding portion, and the other. The front end of the crank arm is bent and formed integrally with a steel wire rod,
A winding portion is rotatably wound around the outer periphery of a pin provided on one side of the seatback frame, and the tip of the other crank arm is inserted into a support hole formed on the other side of the seatback frame. By supporting the seat back frame, the drive mechanism rotates the crank member via the drive arm portion to swing the lower portion of the seat back about the first lateral axis and to move the seat back of the seated person. The force applied from the back to the seat back may be received by elastic deformation of the crank member including a torsion spring configured by a part of the eccentric portion of the crank member, the crank arm portion, the winding portion, and the drive arm portion.

[0006]

As described above, according to the present invention, the eccentric portion of the crank member, which is rotatably supported by the both sides of the seat back frame, can be swung by the first lateral axis located at the upper portion. The seat cushion length is adjusted by engaging the lower rear portion of the seat back supported by the vehicle and rotating the crank member by the drive mechanism to swing the lower portion of the seat back in the front-back direction to adjust the seat cushion length. The device need not be under the seat cushion. Therefore, since it does not interfere with other mechanisms such as a vertical position adjusting mechanism of the seat provided under the seat, the seat cushion length adjusting device can be easily arranged.

Further, the main components other than the seat back are only the crank member and the drive mechanism, so that the structure is simplified and the upper part of the seat back frame is swingably supported and the lower part is the seat cushion. Since the seat back that reaches the vicinity of the upper surface has a larger amount of movement of the lower part in the front-rear direction compared to the swing angle, the adjustment range of the seat cushion length can be increased.

If the crank member is integrally bent with a steel wire and is rotated by the drive mechanism via the drive arm portion, the lower portion of the seat back swings about the first lateral axis. In addition to moving to adjust the seat cushion length, the force applied to the seat back from the back of the seated person is part of the eccentric part of the crank member, the crank arm part,
Since it is received by the elastic deformation of the torsion spring constituted by the winding portion and the drive arm portion, the cushioning action of the seat back is improved.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION A seat cushion length adjusting device according to the present invention will be described below with reference to an embodiment shown in FIGS. The seat cushion length adjusting device of the present invention is provided with a seat back frame 10 and a seat back 20 that is swingably supported on an upper portion of the seat back frame 10.
The seat back 2 is rotated by the drive mechanism 35.
The crank member 30 for moving the lower part of 0 in the front-rear direction is the main constituent member.

As shown in FIGS. 1 to 4, the seatback frame 10 includes an upper pipe 11 which is bent downward in a U shape and a pair of left and right side plates (both sides) extending downward from both ends thereof. (Parts) 12a, 12b and a connecting member 13 for connecting the lower parts thereof, which are loop-shaped and are integrally connected by welding or the like. Seat back frame 10
Is the lower part of the side plates 12a, 12b via the mounting hole 15,
It is attached to brackets attached to both sides of the frame of the seat cushion C or upper arms of the reclining mechanism (both not shown), and stands up above it. A pair of brackets 14 for supporting the upper portion of the seat back 20 described below are provided on the horizontal portion of the upper end of the upper pipe 11.
Are fixed by welding.

As shown in FIGS. 1, 2 and 3, the seat back 20 of this embodiment includes a back panel (sub-frame) 21 formed of synthetic resin and a urethane foam member abutting on the front side thereof. The seat back pad 22 is made up of, and a skin 23 that covers the pad 22 and is attached to the back panel 21. A pair of brackets 24 corresponding to the brackets 14 of the seat back frame 10 are integrally formed on the rear side of the upper portion of the back panel 21. By connecting the left and right brackets 14 and 24 with hinge pins 25, the seat back 20 is supported on the upper part of the seat back frame 10 so as to be swingable around a first horizontal axis O1 having a horizontal upper part, It extends downward along the front side of the back frame 10 and the lower end reaches near the upper surface of the seat cushion C. Seat back frame 10 and seat back 20
The backboard 18 covering the rear side is attached by engaging a pair of hooks 19 on the inner side of the upper part from the lower side with the horizontal part of the upper pipe 11 and screwing the lower end part to the connecting member 13.

As shown in FIGS. 1 to 3, the crank member 30 of this embodiment is formed by integrally bending a steel wire rod (thickness is, for example, 7 mm), and is located at the central portion. Eccentric portion 30a extending parallel to the first lateral axis O1
And a pair of crank arm portions 30b and 30f bent at right angles from both ends thereof and substantially parallel to each other, and a winding portion continuously wound at the tip of one crank arm portion 30b. 30c, a drive arm portion 30d that extends substantially parallel to the crank arm portion 30b continuously with the winding portion 30c, and the tip of the drive arm portion 30d is provided with an eccentric portion 30c.
Tip part 3 bent outward at a right angle and parallel to a
0e and a tip portion 30g formed by bending the tip of the other crank arm portion 30f outwardly in parallel with the eccentric portion 30a.

As shown in FIGS. 1 to 3, a stepped pin 16 is welded and fixed to the inside of one side plate 12a coaxially with a second lateral axis O2 parallel to the first lateral axis O1. A supporting hole 17 is formed in the other side plate 12b. The crank member 30 has one crank arm portion 30.
b The winding portion 30c at the tip end is rotatably wound around the small diameter portion at the tip end of the stepped pin 16, and the tip end portion 30g at the tip end of the other crank arm portion 30f is pivotally supported by the support hole 17 via the bush 31. The seat back frame 10 is rotatably supported by the side plates 12a and 12b of the seat back frame 10 about a second lateral axis O2 that is parallel to the first lateral axis O1.

On the lower rear surface of the back panel 21 of the seat back 20, a pair of left and right vertically long U-shaped members 32 are screwed and fixed by tightening metal fittings 33. Each U-shaped member 3
2 is formed of a material having a small coefficient of friction such as polyacetal resin, and is fixed to the back panel 21 while passing through the eccentric portion 30a of the crank member 30, whereby the crank member 30 can slide substantially only in the vertical direction. It is engaged with the back surface of the crank member 30.

As shown mainly in FIGS. 1 and 2, the arm portion 38 is attached to the support pin 16a which is fixed so as to project inward at a position below the stepped pin 16 of the one side plate 12a.
A sector gear 38 integrally formed with a is rotatably supported. In the long hole 38b (see FIG. 1) formed in the arm portion 38a and extending in the substantially radial direction, the crank member 3
No. 30 of the drive arm portion 30d extending from the winding portion 30c of No. 0.
It is locked by e.

As shown in FIGS. 1, 2 and 3, on the outer surface of one side plate 12a, from the input shaft 36a side to the output shaft 36a.
Rotation is transmitted to the b side, but rotation is not transmitted from the output shaft 36b side to the input shaft 36a side.
Is attached. The input shaft 36 a of the spring coupler 36 protrudes from the side surface of the backboard 18 and the knob 3
9 is fixed, and the pinion 37 fixed to the tip of the output shaft 36b protruding inward of the side plate 12a is meshed with the sector gear 38. These spring couplers 3
6, the pinion 37, the sector gear 38, and the knob 39 configure a drive mechanism 35 that rotates the crank member 30 about the second lateral axis O2.

FIG. 1 shows a state where the seat cushion length is the maximum value D1. From this state, when the knob 39 is manually operated to rotate the pinion 37 in the direction of the arrow A1, the sector gear 38 rotates clockwise around the support pin 16a, and the crank member 30 moves to the second lateral axis. The seat back 20 rotates clockwise about O2, and the seat back 20 swings about the first lateral axis O1 located at the upper part as shown by an arrow B1 so that the lower part of the seat back 20 is seated against the seat cushion C. The seat cushion is moved in a direction that shortens the length. When the pinion 37 is rotated in the direction of arrow A1 to the maximum extent, the seat cushion length shown in FIG. 2 becomes the minimum value D2. From this state, knob 3
By rotating the pinion 37 in the direction of arrow A2 by 9,
The sector gear 38 and the crank member 30 rotate counterclockwise, the seat back 20 swings as shown by arrow B2, and the lower part of the seat back 20 is moved in a direction in which the seat cushion length becomes longer than the seat cushion C. It

As described above, the seat cushion length in this embodiment is adjusted. Since such a seat cushion length adjusting device is provided on the rear side of the seat back 20 and does not need to be provided on the lower side of the seat cushion, it interferes with other mechanisms such as a seat vertical position adjusting mechanism provided on the lower side of the seat. Therefore, the seat cushion length adjusting device can be easily arranged. Also, the seat back 20
Besides, the main components required are only the crank member 30 and the drive mechanism 35, so that the structure is simplified. Further, since the seat back 20 is swingably supported on the upper portion of the seat back frame 10 and reaches the vicinity of the upper surface of the seat cushion C, the amount of movement of the lower portion in the front-rear direction becomes large as compared with the swing angle. This increases the seat cushion length adjustment range.

The force applied to the seat back 20 from the back of the seated person in the use state is transmitted to the arm portion 38a of the sector gear 38 through the crank member 30, and this force is received by the spring coupler 36 and the sector gear 38 is received. It will not be rotated. However, a part of the eccentric portion 30a of the crank member 30 that serves as a transmission path of this force (a portion between the locking portion to the back portion of the seat back 20 and the crank arm portion 30b), the crank arm portion 30b,
Since the winding portion 30c and the drive arm portion 30d form a torsion spring, the seat back 20 is provided with not only the elastic deformation of the pad 22 but also a cushioning function due to the elastic deformation of the torsion spring.

As described above, in the above-described embodiment, the seat back 20 is elastically deformed by the torsion spring in addition to the elastic deformation of the pad 22, so that a good cushioning action is provided. It can also be implemented using a crank member 30. Also, as the sub-frame 21 of the seat back 20, instead of the back panel as described above, a pipe material having a rectangular loop shape and a plurality of S springs stretched is used and abutted on the front side thereof. The seat back 20 may be configured by covering the pad 22 with the outer skin 23 and attaching it.

Further, in the above-described embodiment, the manual knob 39 is used as the drive mechanism 35 for rotating the crank member 30.
Operated by the spring coupler 36, the pinion 3
Although 7 and the sector gear 38 are used, the drive mechanism 35 may be configured by a motor operated by an operation switch and a reduction mechanism that reduces the rotation of the motor and transmits the rotation to the crank member 30.

[Brief description of drawings]

FIG. 1 is a side cross-sectional view of an embodiment of a seat cushion length adjusting device according to the present invention in a state where the seat cushion length is maximized.

FIG. 2 is a side sectional view of the embodiment shown in FIG. 1 in a state where the seat cushion length is minimized.

FIG. 3 is a sectional view taken along line 3-3 in FIG. 1;

FIG. 4 is a sectional view taken along line 4-4 of FIG. 1;

[Explanation of symbols]

10 ... Seat back frame, 12a, 12b ... Side part (side plate), 16 ... Pin (stepped pin), 17 ... Support hole, 2
0 ... Seat back, 30 ... Crank member, 30a ... Eccentric part, 30b ... Crank arm part, 30c ... Winding part, 30
d ... drive arm part, 30f ... crank arm part, 30g
... Tip, 35 ... Drive mechanism, C ... Seat cushion, O
1 ... 1st lateral axis, O2 ... 2nd lateral axis.

Claims (2)

[Claims] 1. A seat cushion length adjusting device in which a seat cushion and a seat back standing upright from a rear portion of the seat cushion are moved relative to each other in a front-rear direction. One end of the seat cushion is attached to a frame of the seat cushion. A seatback frame that rises upward; the seatback, the upper part of which is supported on the upper part of the seatback frame so as to be swingable about a first lateral axis, and the lower part of which reaches near the upper surface of the seat cushion; A crank arm portion whose base end portions are supported on both sides of the seat back frame so as to be rotatable about a second lateral axis line that is substantially parallel to the lateral axis line, and the first end portion of the crank arm portion. An eccentric portion which is provided in parallel with the lateral axis of the second seat and is engaged with the lower rear portion of the seat back so as to be slidable substantially only in the vertical direction. A seat cushion length adjusting device, comprising: a crank member including: and a drive mechanism that is provided in a part of the seat back frame and that rotates the crank member around the second lateral axis. 2. The crank member includes the eccentric part, a pair of the crank arm parts bent from both ends thereof at a substantially right angle and substantially parallel to each other, and one tip of the crank arm part. A winding portion formed continuously with the winding portion, a drive arm portion further extending continuously with the winding portion, and a tip portion formed by bending the tip of the other crank arm portion in parallel with the eccentric portion. The winding portion is integrally formed by bending with a steel wire rod, and the winding portion is rotatably wound around the outer periphery of a pin provided coaxially with the second lateral axis on one side portion of the seat back frame. And, the other end of the seatback frame is supported by the seatback frame by inserting the tip of the other crank arm into a support hole formed coaxially with the second lateral axis. The drive mechanism is The seat cushion length adjusting device according to claim 1, wherein the crank member is engaged with a tip end portion of a drive arm portion of the crank member to rotate the crank member via the drive arm portion.