JP2005138675A - Seat back for vehicle seat - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress a sense of incongruity of a back rest at a boundary between a portion with a supporting body and a portion without any supporting portion by smoothly supporting a back of a seated person in a seat back structure of a vehicle seat in which an upholstery material of a steric woven object is covered and stretched over a seat frame. <P>SOLUTION: In a seat back structure of a vehicle seat, a seat frame 10 to form a skeleton of a seat back has a side frame 10b on right and left sides, and an upholstery material with at least a back rest surface of a seated person formed of a steric woven object is covered over the seat frame 10. On a back side of the back rest surface of the upholstery material, a supporting body 20 having the surface shape corresponding to a shape of a back of the seated person is integrated with the back rest surface of the upholstery material, and both the back rest surface of the integrated upholstery material and the supporting body 20 are tension-supported by the side frames 10b disposed on the right and left sides via elastic means 41 and 42. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a seat back structure for a vehicle seat. In particular, the present invention relates to a seat back structure for a vehicle seat formed by covering a skin material of a three-dimensional knitted fabric on a seat frame.

As a part of weight reduction for vehicle seats, a vehicle seat having a seat back formed by covering a skin material of a three-dimensional knitted fabric (hereinafter referred to as “(three-dimensional knitted) net body”) on a seat frame has been developed. Has been. However, in such a so-called net seat, the skin material of the net body has great elasticity, so the back of the seated person sinks into the seat back due to its own weight. Therefore, there is a problem in that the seated person does not support the lumbar portion, and a correct sitting posture cannot be obtained, resulting in discomfort.
As a conventional technique for solving this problem, a seat back structure in which a belt-like support is provided on a back support surface as described in Patent Document 1 is known.

The conventional seat back structure will be described with reference to FIGS. 9 is a perspective view of the seat back in a state where the skin material is not covered, and FIG. 10 is a cross-sectional view taken along line XX of the seat back in FIG. 9 in a state where the skin material is covered.
As well shown in FIG. 9, the seat back 2 has left and right side frames of the seat frame 10 formed in a substantially square frame shape including an upper frame 10a, left and right side frames 10b and 10b, and a lower frame 10c. A belt-like support 70 having elasticity or stretchability is passed between 10b and 10b. 10, the seat back 2 has the net body skin material 31 covered and stretched on the seat frame 10 so that the lumbar portion of the seated person has the net body skin material 31 and the belt-like support body 70. It is the structure supported by.
JP 2003-116663 A

  However, the above-described conventional seat back has the following problems. That is, (1) The amount of flexion of the epidermis changes abruptly between where the belt-like support is present and where it is not, and the occupant feels uncomfortable on the back. In addition, since the part removed from the belt-like support is supported only by the skin material, it will sink into the seat back, and (3) the belt-like support is formed from a skin material having elasticity or elasticity such as a net body, for example. Therefore, there is no spring feeling in the repulsive force, and it seems that the supporting force of the lumbar part is insufficient.

  The present invention was devised in view of the above points, and the problem to be solved by the present invention is to smooth the back support of the seated person and to hit the back of the boundary between the part with and without the support. It is to suppress the sense of incongruity.

In order to solve the above problems, the present invention takes the following means.
The seat back structure for a vehicle seat according to the first invention takes the following means. That is, the seat frame that forms the skeleton of the seat back has side frames on both the left and right sides, and a seat for a vehicle seat that is formed by covering the seat frame with a skin material in which at least a backrest surface of a seated person is a three-dimensional knitted fabric. In the back structure, on the back side of the back contact surface of the skin material, a support body having a surface shape corresponding to the back shape of the seated person is integrated with the back contact surface of the skin material, and this integrated skin Both portions of the back-contact surface of the material and the support are tension-supported by elastic means on the side frames disposed on the left and right sides.
Here, the “elastic means” is arbitrary as long as it can support tension by elastic deformation, and specifically, springs such as coil springs and torsion bars, or rubbers are applicable.
According to the first aspect of the present invention, since the surface-shaped support body supports the entire seating surface of the seated person, the seated person's lumbar portion can be reliably supported and the entire back surface can be supported smoothly. .

Further, the seat back structure for a vehicle seat according to the second invention takes the following means. That is, the side frame is formed with a predetermined width in the vehicle front-rear direction, and the tension support by one elastic means of the two integrated parts to the side frame is provided by two springs. The position where one spring is attached to the side frame is pulled rearward as the rear position of the side frame formed with a width, and the other spring is The mounting position to the side frame is set to be a front position from the mounting position of the one spring, and both the integrated members are pulled.
According to the second aspect of the present invention, the back contact surface of the seat back surface can be pulled rearward simultaneously with the support, so that the positional relationship of the back contact surface of the seat back surface with respect to the side frame changes its tension. Can be adjusted.

The seat back structure for a vehicle seat according to the third aspect of the invention takes the following means. That is, in the seat back structure for a vehicle seat according to the first or second invention described above, the tension support by the elastic means of the two integrated members to the side frame is in the vertical direction of the side frame. It is performed at a plurality of locations, and the elastic modulus of the elastic means arranged at the upper position is larger than the elastic modulus of the elastic means arranged at the lower position.
According to the third aspect of the present invention, the seatback's lumbar vertebrae portion, which adds the most weight to the backrest surface, reduces the seatback penetration due to the small elastic modulus, while the other portions have a moderate elastic modulus due to the large elastic modulus. Can give a good cushioning property.

Further, the seat back structure for a vehicle seat according to the fourth aspect of the invention takes the following means. That is, in the seat back structure for a vehicle seat according to the first to third inventions described above, the support is formed of an elastic resin plate, and the lower position has higher rigidity than the upper position. It is formed.
According to the fourth aspect of the invention, it is possible to adjust the bending characteristics of the seat back even with a single member called a resin plate. Furthermore, while supporting the seated person's lumbar portion reliably at the lower position of the seat back, it is possible to provide an appropriate cushioning property at the upper position in combination with the elastic means.

The seat back structure for a vehicle seat according to the fifth aspect of the invention takes the following means. That is, in the seat back structure for a vehicle seat according to the above-described fourth invention, ribs are formed on the back surface of the lower position of the support body, and as it goes from the left and right sides of the support body to the central portion. The thickness of the rib in the front-rear direction is gradually increased.
According to the fifth aspect of the invention, the rigidity of the lumbar support portion of the seated person at the lower position of the seat back can be increased.

The present invention can obtain the following effects by taking the above-described means.
According to the first invention, the back of the seated person does not sink into the seat back due to its weight. Furthermore, since the support body supports the entire back contact surface, it is possible to suppress a sense of discomfort with respect to the back contact surface at the boundary between the portion where the support body is present and the portion where the support body is absent.
Further, according to the second invention, the back-contacting surface can be pulled down to the rear side rather than the left and right ends on the seat back surface, so that the shape of the seat back surface is clearly defined. As a result, the appearance quality of the sheet is improved.
Moreover, according to the 3rd invention, a seated person's backrest can be supported more smoothly.
Further, according to the fourth aspect, in the seat back, it is easy to adjust the flexural characteristics that change between the upper position and the lower position.
Further, according to the fifth aspect, the seated person can reliably support the lumbar portion, so that a correct sitting posture without bending the lumbar vertebra can be obtained. As a result, a feeling of fatigue due to sitting for a long time can be suppressed.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

This embodiment is shown in FIGS. FIG. 1 is a perspective view of a vehicle seat according to the present embodiment, FIG. 2 is a perspective view of a seat back of the vehicle seat in a state where the skin material is not covered, and FIG. 3 is a vehicle seat according to the present embodiment. 4 is a cross-sectional view taken along the line IV-IV in FIG. 1, FIG. 5 is a cross-sectional view taken along the line V-V in FIG. 1, and FIG. 6 is a seat of the vehicle seat according to the present embodiment. It is an expansion perspective view near the engaging part of a support in a back.
In the present embodiment, the direction designations are “front-rear direction” as the vehicle front-rear direction, and “left-right direction” or “side direction” as the left-right direction of the vehicle. Also, members corresponding to those shown in FIGS. 9 and 10 are given the same reference numerals.

First, a seat back structure for a vehicle seat according to this embodiment will be described with reference to FIGS. 1 and 2.
The vehicle seat according to the present embodiment is composed of three members, a seat cushion 1, a seat back 2, and a headrest 3. The positional relationship of these members is shown in FIG.
Here, in the seat back 2, a net body skin material 30 is stretched over the seat frame 10 on the surface on the seated person side, and a non-net body skin material 31 that is not necessarily a net body is provided on the other surface. The seat frame 10 is covered and stretched. Further, the net body skin material 30 is formed by joining a back net body skin material 30a on the back contact surface and side net body skin materials 30b on the left and right sides of the back contact surface. On the other hand, the non-net body skin material 31 is formed by joining a back skin material 31 a on the back surface of the seat back 2 and a side skin material 31 b on the side surface of the seat back 2.
The above-described skin materials 30, 31 are joined by, for example, sewing. Moreover, the joined skin material is formed in a substantially cylindrical shape as a whole, and the curves drawn on the surface and side surfaces of the seat back 2 in FIG. 1 are the results of joining these skin materials 30, 31. The resulting joining line 32 is shown.

Incidentally, the step of stretching the skin materials 30 and 31 to the seat frame 10 is performed by covering the seat frame 10 with a stretchable substantially cylindrical skin material to which the skin materials 30 and 31 are joined in advance. . That is, first, the substantially cylindrical skin material whose upper and lower ends on the back side of the seat back 2 are open / close ends is lifted up above the seat frame 10 with the back side of the seat back 2 opened. After attaching the member such as the support 20 to the seat frame 10, the raised skin material is lowered to cover the entire seat frame 10, and finally the open / close ends of the upper and lower ends of the skin material are velvet fasteners, etc. To complete the tensioning process.
Further, as shown in FIGS. 4 and 5, a pad 50 formed of foamed resin or the like is actually incorporated in the contact surface between the seat frame 10 and the skin materials 30 and 31.
In addition, about the structure of the seat cushion 1 and the headrest 3, it is comprised by the known general structure.

Next, based on FIG. 2, the internal structure of the seat back 2 in a state where the above-described skin materials 30, 31 are removed will be described.
Inside the seat back 2, the seat frame 10 formed by bending a metal integral molded product such as magnesium or aluminum or a metal belt-like flat plate such as iron so as to determine its outer shape has four sides on the upper frame 10a. , A side frame 10b, 10b and a lower frame 10c. The upper frame 10a is located at the upper part of the seat frame 10, and has a substantially S-shaped cross section in which one edge is bent inward and the other edge is bent outward. The part which becomes a frame of 3 is extended in the upper part. The lower frame 10c extends linearly between the side frames 10b and 10b in the lower part of the seat frame 10, and the cross section thereof is a U-shape. Further, the two side frames 10b are positioned in pairs on the left and right sides of the seat frame 10, and the front edge thereof is bent outward and the rear edge thereof is bent inward. The cross section is substantially S-shaped.
Note that the side frame 10b has a predetermined width in the front-rear direction that substantially matches the front-rear width of the seat back 2. In addition, an upper locking protrusion 11a and a lower locking protrusion 11b having a U-shaped cross section are provided at approximately two locations, an upper portion and a lower portion, on the inner side of the central portion of the predetermined width by integral molding or welding or the like. ing. On the other hand, at the rear edge of the side frame 10b, an upper locking hole 12a and a lower locking hole 12b are formed at positions corresponding to the upper locking protrusion 11a and the lower locking protrusion 11b. The positions of the locking protrusions 11 and the locking holes 12 are determined by the position and size of the support 20.

Here, one end of the front coil spring 41 is locked to each of the upper locking protrusion 11a and the lower locking protrusion 11b, and one end of the rear coil spring 42 is locked to each of the upper locking hole 12a and the lower locking hole 12b. Is locked. Further, the other ends of the front coil spring 41 and the rear coil spring 42 are engaged with the lightening holes 22 in the upper and lower portions of the planar support 20. Therefore, as well shown in FIG. 2, the two coil springs of the front coil spring 41 and the rear coil spring 42 tension-support the support body 20 from both the upper and lower left and right sides.
The tension-supported support body 20 is provided with a hollow hole 22 on substantially the entire surface for the purpose of weight reduction. The hollow hole 22 is formed on both the coil springs 41 and 42 on the support body 20 side. It also functions as a locking hole. Further, in this embodiment, the front coil spring 41 is engaged with the thinning holes 22 at the uppermost part and the lowermost part of the support 20, and the meat at the lowermost and lowermost positions of the uppermost hollowing hole 22. Although the rear coil spring 42 is locked on one of the holes 22, the locking position of the coil springs 41 and 42 is not limited to this position. The support 20 can be provided with a locking hole separate from the lightening hole 22.

Next, the structure of the support 20 will be described with reference to FIGS.
The support 20 is a resin plate having a curved shape that follows the line of the spine 61 of the seated person 60 when viewed from the side, and a substantially rectangular shape when viewed from the front. Further, the size of the seat 60 is such that the back of the seated person 60 can substantially cover the back contact surface in contact with the seat back 2. That is, the length of the support 20 in the vertical direction is such that it can support from the lumbar portion 61a of the seated person 60 to the approximate middle of the thoracic vertebra portion 61b, as well shown in FIG. The length in the left-right direction is a length that can support the back of the seated person 60, as well shown in FIG. Accordingly, the support body 20 covers the surface of the seated person 60 where the back of the seat 60 hits the seat back 2, but is supported by the front and rear coil springs 41 and 42 around the periphery of the support body 20 so as to freely move within the seat frame 10. It has a margin of degree.

Further, as shown in FIGS. 3 and 4, on the back surface of the support 20, in the substantially lower half where the lumbar portion 61 a of the seated person 60 hits, one vertical rib 21 a is provided in the central vertical direction. Two horizontal ribs 21b are extended in parallel in the left-right direction. The thickness of the longitudinal rib 21a in the front-rear direction is gradually increased from both the upper and lower sides toward the substantially center of the lumbar portion 61a of the seated person 60, while the thickness in the front-rear direction of the lateral rib 21b is increased from the left and right sides to the central portion. It gradually gets thicker as you head. Thereby, the bending characteristic of the support body 20 is adjusted so that the rigidity is maximized in the lumbar portion 61 a of the seated person 60.
In addition, adjustment of the bending characteristic of the support body 20 is implement | achieved also by changing the magnitude | size of the lightening hole 22 besides the above-mentioned rib 21. FIG. That is, as well shown in FIGS. 2 and 3, the area of the cutout hole 22 to be drilled is the smallest at the place where the rigidity is the largest, and the area is the largest at the place where the rigidity is the smallest. ing.

Next, a state in which the support 20 is tension-supported integrally with the net body skin material 31 will be described with reference to FIGS. 5 and 6.
A cross-sectional view taken along line V-V in FIG. 1, that is, a cross-sectional view including an upper portion of the support 20 in the seatback 2 is shown in FIG. 5. The support body 20 and the back net body skin material 30a are superposed together without any intervening members, and the left and right ends thereof are further connected to one end of the side net body skin material 30b and an iron C-ring or thread, string, clamp They are joined together by a belt or the like. Furthermore, the other end of the side net body skin material 30b and one end of the side skin material 31b, the other end of the side skin material 31b, and one end of the back skin material 31a are joined together by sewing or the like. The outer peripheral portion of the cross section is joined endlessly.
In addition, it is preferable to insert a pad 50 formed of foamed resin or the like between the front surface portion of the seat frame 10 and the skin materials 30 and 31 for the purpose of shaping and the sitting comfort of the seated person.

On the other hand, in the support body 20 and the back net body skin material 30a that are integrally stacked, as shown in FIG. 6, the front coil spring 41 and the rear coil are formed in the lightening holes 22 formed in the support body 20. One end of the spring 42 is locked. As shown in FIG. 5, the other end of the front coil spring 41 is locked to the upper locking protrusion 11a inside the substantially central portion of the side frame 10b, and the other end of the rear coil spring 42 is the side frame. It is latched by the upper latching hole 12a drilled at the rear edge of 10b.
As a result, the back net body skin material 30a is pulled rearward simultaneously with the support body 20, and a sheet having a well-defined external shape is realized in which the back contact surface is pulled backward from the side portion. Of course, this shaping can be easily performed by adjusting the elastic modulus of the rear coil spring 42.
In addition, although the above-mentioned tension | tensile_strength support location was the upper end part of the support body 20, the lower end part of the support body 20 is also the same. The same applies to the case where the tension support extends to a plurality of locations other than the two locations of the upper end portion and the lower end portion.

The present embodiment is a variation of the first embodiment and is shown in FIGS. FIG. 7 and FIG. 8 are enlarged perspective views of tension support portions of the support and the side frame in the seat back of the vehicle seat according to the present embodiment.
First, one variation is shown in FIG. The difference between this variation and Example 1 is the difference in the tension support member. That is, a torsion bar 44 is used as an alternative member of the front coil spring 41 and is stretched between the locking protrusion 11 of the side frame 10 b and the lightening hole 22 of the support 20.
By using the torsion bar 44, there is an advantage that it is possible to save space compared to the front coil spring 41.

Next, another variation is shown in FIG. The difference between this variation and Example 1 is the shape of the locking protrusion. That is, in the first embodiment, a vertically long hole 13 is formed at a position on the inner side of the side frame 10b where the locking protrusion 11 having a U-shaped cross section is provided. The hook 14 is inserted and the front coil spring 41 is locked.
The use of the hook 14 has an advantage that a process such as complicated molding or welding of the locking protrusion 11 to the side frame 10b can be omitted.

It is a perspective view of the vehicle seat which concerns on Example 1 of this invention. It is a perspective view which shows the internal structure of the seat back of the vehicle seat which concerns on Example 1 of this invention. It is a back surface perspective view of the support body of the seat back of the vehicle seat which concerns on Example 1 of this invention. It is the IV-IV sectional view taken on the line of FIG. It is the VV sectional view taken on the line of FIG. It is an expansion perspective view near the support body engaging part of the seat back structure of the vehicle seat which concerns on Example 1 of this invention. It is an expansion perspective view of the tension support location of one variation of Example 1 of the present invention. It is an expansion perspective view of the tension support location of other variations of Example 1 of the present invention. It is a perspective view which shows the internal structure of the seat back of the conventional vehicle seat. FIG. 10 is a sectional view taken along line XX in FIG. 9.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Seat cushion 2 Seat back 3 Headrest 10 Seat frame 10a Upper seat frame 10b Side frame 10c Lower frame 11 Locking protrusion 11a Upper locking protrusion 11b Lower locking protrusion 12 Locking hole 12a Upper locking hole 12b Lower hook Stop hole 13 Long hole 14 Hook 20 Support body 21 Rib 21a Vertical rib 21b Horizontal rib 22 Meat hole 30 Net body skin material 30a Back net body skin material 30b Side net body skin material 31 Non-net body skin material 31a Back skin material 31b Side skin material 32 Skin material joint line 41 Front coil spring 42 Back coil spring 43 C ring 44 Torsion bar 50 Pad 60 Seated person 61 Seated person spine 61a Lumbar vertebra 61b Thoracic vertebra 61b Cervical vertebra 70 Banded support

Claims (5)

A seat frame forming a skeleton of a seat back has a side frame on both the left and right sides, and a seat back structure for a vehicle seat in which a seat material having at least a back contact surface of a seated person as a three-dimensional knitted fabric is covered on the seat frame Because
On the back side of the back contact surface of the skin material, a support having a surface shape corresponding to the back shape of the seated person is integrated with the back contact surface of the skin material, and the back contact surface of the integrated skin material and 2. A seat back structure for a vehicle seat, wherein both parts of the support are tension-supported by elastic means on the side frames arranged on the left and right sides. The vehicle seat back structure according to claim 1,
The side frame is formed with a predetermined width in the vehicle front-rear direction, and tension is supported by two springs at one of the integrated portions on the side frame by two springs. The position where one spring is attached to the side frame is the rear position of the side frame formed with a width, and the two integrated parts are pulled backward, and the other frame is attached to the side frame. A seat back structure for a vehicle seat, wherein the integrated member is pulled by setting the mounting position to a front position from the mounting position of the one spring. The vehicle seat back structure according to claim 1 or 2,
The tension support of the integrated members on the side frame by the elastic means is performed at a plurality of locations in the vertical direction of the side frame, and the elastic modulus of the elastic means arranged at the upper position is arranged at the lower position. A seat back structure for a vehicle seat, wherein the elastic modulus is greater than an elastic modulus of the elastic means. A vehicle seat back structure according to any one of claims 1 to 3,
A seat back structure for a vehicle seat, wherein the support is formed of an elastic resin plate, and the lower position is higher in rigidity than the upper position. The vehicle seat back structure according to claim 4,
Ribs are formed on the back surface of the lower position of the support, and the thickness of the ribs in the front-rear direction gradually increases from the left and right sides of the support toward the center. Seat back structure.

Images