JP3458441B2 - Lumbar support mechanism for vehicle seats - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a lumbar support mechanism which is mounted on a seat back of a vehicle seat to press and support a lumbar portion of a seated person.

[0002]

2. Description of the Related Art A vehicle seat lumbar support mechanism is
By adjusting the support strength for the lumbar vertebrae of the seated person according to preference, fatigue during long-distance running is reduced.

As such a lumbar support mechanism, a rectangular flat plate-shaped pressing member which is brought into contact with the back surface of a cushion pad which constitutes a seat back, a support frame which is integrally assembled to the back surface of the pressing member, and the support. The frame includes a support arm having its front end coupled to the rear surface of the frame to apply a forward pressing force to the support frame, and the forward pressing force applied to the support frame causes the pressing member to move to the cushion pad rear surface. There is a configuration in which the portion corresponding to the lumbar portion of the seated person is pushed forward to press and support the lumbar portion of the seated person.

[0004]

Since the above-mentioned conventional lumbar support mechanism has a structure in which the cushion pad is pushed forward through a simple rectangular flat plate-shaped pressing member, a forward pushing force is applied to the support frame. When applied, the supporting pressure on the surface of the cushion pad corresponding to the lumbar vertebra of the seated person changes rapidly near the upper and lower ends of the flat pressing member. Therefore, there is a problem in that the seated person lacks adaptability to the lumbar vertebrae, and the seated person feels uncomfortable as a line contact between the upper and lower end portions of the flat plate pressing member through the cushion pad.

In order to solve the above problems, the present invention makes the change in the support pressure on the cushion pad surface near the upper and lower ends of the flat plate pressing member continuous and gentle when the cushion pad is pushed forward. Therefore, it is an object of the present invention to improve the adaptability of the seated person to the lumbar region and provide a comfortable lumbar support mechanism that does not make the seated person feel the upper and lower ends of the flat plate-shaped pressing member as line contact.

[0006]

In order to achieve the above object, the present invention provides the above-mentioned conventional lumbar support mechanism, wherein the flat plate pressing member is formed of a flexible material,
A structural feature is that a plurality of slits are provided in the upper and lower portions at predetermined intervals in the vertical direction.

In addition to the above characteristics, the present invention also provides
A bulging portion having a trapezoidal cross-sectional shape with a gentle inclination and a surface parallel to the back surface of the cushion pad having a shape corresponding to the support frame is formed in a portion of the back surface of the cushion pad corresponding to the lumbar region of the occupant. Is a structural feature.

Further, it is structurally characterized in that the plurality of slits are provided at equal intervals at an upper end portion and a lower end portion of the flat plate pressing member.

Further, a structural feature is that a circular punched hole having a diameter larger than the width of the slit is formed at each inner end of the slit.

[0010]

In the lumbar support mechanism of the present invention described above, when a forward pressing force is applied to the support frame, the flat plate pressing member is pressed against the cushion pad and the upper end provided with the slit is provided. The part and the lower end part are deformed so as to warp backward. Therefore, it is possible to make the change in the supporting pressure on the surface of the cushion pad near the upper and lower ends of the flat pressing member continuous and gradual. As a result, it is possible to provide a comfortable lumbar support mechanism that improves the adaptability of the seated person to the lumbar region and does not make the seated person feel the upper and lower ends of the flat plate-shaped pressing member as a line contact.

When the bulging portion is formed on the back surface of the cushion pad, the bulging portion provided on the back surface of the cushion pad is deformed so as to be crushed when a forward pressing force is applied to the support frame. To do. At this time, since the pressing force does not act directly on the inclined surface of the bulging portion, the pressing force applied to the bulging portion gradually decreases toward the peripheral portion. As a result, the change in the supporting pressure of the portion supporting the lumbar vertebra of the seated person on the cushion pad surface becomes continuous and gentle over a wider range of extrusion amount as compared with the structure having no bulging portion on the back surface of the cushion pad, The adaptability of the seated person to the lumbar region can be further improved.

Further, when the slits are provided at equal intervals, the upper and lower end portions of the flat plate-like pressing member are uniformly bent, so that the adaptability of the seated person to the lumbar vertebrae can be appropriately increased.

Furthermore, when a circular punched hole is formed at each inner end of the slit, it is possible to reliably prevent tearing at the inner end of each slit.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 schematically shows the structure of a seat back of a vehicle seat equipped with the lumbar support mechanism of the present invention. The cushion pad 31 formed of urethane foam or the like is integrally assembled to the back frame structure 21. In the back frame structure 21, two S-shaped springs 23 are laterally stretched on a back frame 22 formed of a pipe material in a frame shape.
3 are connected by a vertical spring 24.

The flat plate-shaped pressing member 11 constituting the lumbar support mechanism 10 is made of a flexible material such as synthetic resin, hard rubber, aluminum or iron, and is arranged below the central portion of the back frame 22. The cushion pad 11 is in contact with the back surface of the portion that supports the lumbar portion of the seated person.

As shown in FIG. 2, the flat plate pressing member 11
A plurality of slits 11a are provided in the vertical direction at equal intervals at the upper end portion and the lower end portion, respectively. Each slit 1
The width of 1a is almost the same as the thickness of the flat pressing member 11. Further, the slits 11 are provided at the inner end of each slit 11a.
a circular punched hole 11 having a diameter larger than the width of a
b is formed.

The flat plate-shaped pressing member 11 has tabs 12a formed by cutting and raising the support frame 12 to form a flat plate-shaped pressing member 11.
It is integrally fixed to the support frame 12 by being inserted into a hole 11d provided in the and caulking. The support frame 12 is horizontally rotatably attached to the front end of a support arm 13 formed of a steel wire or the like at the center of the back surface thereof. The support frame 12 is formed of an iron plate or the like.

The base end of the support arm 13 is attached to a gear box 14 fixed to one side of the back frame 22. The gear box 14 is driven by a motor 15 fixed to the back frame 22.

In the lumbar support mechanism configured as described above, when the motor 15 shown in FIG. 1 is activated, the gear box 14 rotates the tip end of the support arm 13 forward with the base end of the support arm 13 as a fulcrum. To move. As a result, the support frame 12 attached to the tip of the support arm 13 is pushed forward, and the flat plate-shaped pressing member 11 attached to the surface of the support frame 12 pushes the abutting cushion pad 31 forward from its back surface. . At this time, since the flat plate-shaped pressing member 11 is formed of a flexible material and the slits 11a are provided, the upper end portion and the lower end portion 11c of the flat plate-shaped pressing member 11 warp rearward as shown in FIG. Is elastically deformed. Therefore, the change in the supporting pressure on the surface of the cushion pad near the upper and lower end portions of the flat plate-shaped pressing member 11 can be made continuous and gentle, and the adaptability of the seated person to the lumbar vertebrae can be improved, and the flatness of the seated person can be improved. It is possible to provide a comfortable lumbar support mechanism that does not make the upper and lower end portions 11c of the linear pressing member 11 feel like a line contact.

Further, by providing the slits 11a at equal intervals, the elastic deformation of the flat plate pressing member 11 in the rearward direction becomes uniform over the entire width of the flat plate pressing member 11.

Further, by providing the punching hole 11b, even if the flat plate pressing member 11 is repeatedly elastically deformed, it is prevented from tearing from the inner end of the slit 11a.

Next, a second embodiment of the present invention will be described with reference to FIGS.

In the second embodiment, in addition to the structure of the first embodiment, a bulge having a trapezoidal cross section having the gentle slope shown in FIG. 4 on the back surface of the portion of the cushion pad 31 supporting the lumbar spine of the seated person. The part 31a is integrally formed. A surface 3 of the bulging portion 31a parallel to the back surface of the cushion pad 31.
1b has a shape corresponding to the shape of the support frame 12.

The bulging portion 31a is deformed so as to be crushed via the flat plate-shaped pressing member 11 when the supporting arm 13 is rotated and a forward pressing force is applied to the supporting frame 12. At this time, since the surface 31b of the bulging portion 31a corresponds to the shape of the support frame 12, the support frame 12 substantially pushes the surface forward. Therefore, the pressing force applied to the bulging portion 31a does not directly act on the inclined portion 31c, but gradually decreases toward the peripheral portion of the bulging portion 31a. As a result, when the support frame 12 is pushed forward, the change in the support pressure in the portion of the surface of the cushion pad 31 that supports the lumbar portion of the seated person becomes continuous and moderate.

When the support frame 12 is pushed further forward than the thickness of the bulging portion 31a, the surface of the cushion pad 31 is pushed further forward. At this time, as shown in FIG. 5, the flat plate-shaped pressing member 11 of the first embodiment described above is elastically deformed so as to warp rearward. Therefore, the change in the support pressure of the portion of the surface of the cushion pad 31 that supports the lumbar portion of the occupant changes on the back surface of the cushion pad 31.
Compared with the structure having no a, it becomes continuous and gentle over a wider range of extrusion amount, the adaptability to the lumbar part of the seated person can be further improved, and the upper and lower end portions of the flat plate-shaped pressing member 11 for the seated person can be further improved. A comfortable lumbar support that does not make 11c feel like a line hit is provided.

The cushion pad 31 has a bulging portion 31.
Since the thickness of the cushion pad 31 itself is increased by providing a, the cushioning property of the portion supporting the lumbar portion of the seated person is also improved.

[Brief description of drawings]

FIG. 1 is a perspective view of a first embodiment of the present invention.

FIG. 2 is a partially enlarged view of the first embodiment of the present invention.

FIG. 3 is a sectional view showing the operation of the first embodiment of the present invention.

FIG. 4 is a sectional view showing the operation of the second embodiment of the present invention.

FIG. 5 is a sectional view showing the operation of the second embodiment of the present invention.

[Explanation of symbols]

11 ... Flat plate pressing member, 11a ... Slit, 11b ... Punch hole, 12 ... Support frame, 13 ... Support arm, 1
4 ... Gear box, 15 ... Motor, 21 ... Back frame structure, 22 ... Back frame, 31 ... Cushion pad, 31a ... Swelling part.

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Claims (4)

(57) [Claims] 1. A rectangular flat plate-shaped pressing member that is in contact with the back surface of a cushion pad that constitutes a seat back, a support frame that is integrally assembled to the back surface of the pressing member, and a tip thereof on the back surface of the support frame. And a supporting arm for applying a forward pressing force to the supporting frame, and the forward pressing force applied to the supporting frame causes the pressing member to move to the lumbar region of the seated person on the back surface of the cushion pad. A lumbar support mechanism for a vehicle seat configured to push out a corresponding portion forward to press and support a lumbar portion of a seated person, wherein the flat plate pressing member is formed of a flexible material, and the flat plate pressing member is formed. A lumbar support mechanism for a vehicle seat, wherein a plurality of slits are provided at predetermined intervals at upper and lower ends of the vehicle, respectively. 2. A portion of the back surface of the cushion pad corresponding to the lumbar region of the seated person is a trapezoid having a gentle slope in cross section, and a surface parallel to the back surface of the cushion pad corresponds to the support frame. The lumbar support mechanism for a vehicle seat according to claim 1, wherein a bulge portion is formed. 3. The lumbar support mechanism for a vehicle seat according to claim 1, wherein the plurality of slits are provided at equal intervals at an upper end portion and a lower end portion of the flat plate pressing member. 4. The lumbar support mechanism for a vehicle seat according to claim 1, wherein a circular punched hole having a diameter larger than a width of the slit is formed at each inner end of the slit.