JP3564809B2 - Lumber support device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to a lumbar support device that supports a lumbar portion of a back of a seated person and that can adjust the degree of support.
[0002]
[Prior art]
Conventionally, as this kind of lumbar support device, one disclosed in Japanese Patent Application Laid-Open No. 62-68411 is known. This has a spring structure that supports the back of the seated person, a frame that supports the spring structure, and an adjustment mechanism that presses and adjusts the lumbar support portion of the spring structure in the thickness direction of the seat back. . In this conventional device, the adjustment mechanism is operated to press the lumbar support portion of the spring structure in the thickness direction of the seat back, so that the occupant of the occupant due to the reaction force generated when the occupant leans on the seat back. The lumbar support was adjusted.
[0003]
[Problems to be solved by the invention]
However, in the above-described conventional apparatus, the reaction force for determining the support condition is concentrated on the lumbar spine portion of the seated person. For this reason, the seated person feels the reaction force as a foreign object feeling, and as a result, there is a fear that the seated person may feel uncomfortable sitting.
[0004]
Therefore, an object of the present invention is to prevent a reaction force for determining a support condition of a lumbar portion of a seated person from giving a feeling of a foreign object to the seated person.
[0005]
[Means for Solving the Problems]
The technical measures taken in the present invention to solve the above technical problem include a spring structure for supporting the back of a seated person, and a spring structure in a seatback thickness direction at a first predetermined portion in the seatback vertical direction. A frame that rotatably supports the spring structure and an adjustment mechanism that rotates the spring structure about the first predetermined portion to adjust a tilt angle of a back support surface of the spring structure in a seat back thickness direction. Yes, and the first predetermined portion is characterized in that located between the lumbar support portion and thoracic support portion of the back support surface, is that.
[0006]
According to this technical means, when the adjusting mechanism is actuated, the spring structure rotates and the inclination angle of the back support surface in the seat back thickness direction is adjusted. As a result, the lumbar support portion of the back support surface is moved in the thickness direction of the seat back, and as a result, the support condition of the lumbar portion of the occupant due to the reaction force generated when the occupant leans on the seat back is adjusted. You. At this time, since the inclination angle of the back support surface of the spring structure is adjusted, the reaction force that determines the degree of support of the lumbar spine portion of the seated person is distributed over the entire back of the seated person. Therefore, the reaction force that determines the support condition of the lumbar spine portion of the seated person does not give the seated person a foreign object feeling. Further, since the center of rotation of the spring structure is the first predetermined portion located between the lumbar support portion and the thoracic vertebra support portion of the back support surface, a large change amount with respect to the adjustment width in the seat back thickness direction. Can be obtained.
[0008]
More preferably, the adjusting mechanism has an elastic body supported by the frame so as to be movable in the seat back thickness direction and connected to a second predetermined portion of the spring structure in a seat vertical direction. good.
[0009]
More preferably, the elastic body is formed integrally with the spring structure.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
As shown in FIG. 1, the lumbar support device includes a frame 1, a spring structure 2, and an adjustment mechanism 3.
[0011]
The frame 1 is a rigid body of the seat back 6 and has an inverted U shape including side portions 11 and 12 located on both sides and an upper portion 13 located on an upper portion.
[0012]
The spring structure 2 serves as an elastic body of the seat back 6 and is provided between both side portions 11 and 12 of the frame 1 and is configured by combining a plurality of wires made of a spring material. It has a rectangular shape. In the spring structure 2, a pair of arm portions 21 serving as a support portion to the frame 1 and a pair of leg portions 22 serving as a connection portion to the adjustment mechanism 3 are formed by a main body 23 constituting a back support surface 23 a of the seated person. It is formed to be bent in the seat back thickness direction (the paper surface direction shown in FIG. 1 and the horizontal direction shown in FIG. 2). The arm portion 21 is located at a first predetermined portion 24 between the waist support portion 231a and the chest support portion 232a of the back support surface 23a, and the leg portion 22 is positioned above and below the back support surface 23a. It is located at a second predetermined portion 25 which is a lower portion in the direction (the vertical direction shown in FIGS. 1 and 2).
[0013]
The adjustment mechanism 3 includes an operation unit 31 and a crank rod 32.
[0014]
The operation unit 31 is rotatably supported via a bracket 31a at a lower portion of the side portion 11 of the frame 1 in the vertical direction of the seat back, and is a known brake member such as a spring coupler, an operation handle serving as an input member, and a pinion gear serving as an output member. And a sector gear 31c rotatably supported by the side portion 11 of the frame 1 via a bracket 31a and meshed with the rotating shaft 31b. The crank rod 32 has a rigid rod shape and is disposed between both side portions 11 and 12 of the frame 1. One end 32a is connected to the sector gear 31c of the operation unit 31, and the other end 32b is connected to the sector gear 31c. 31c is rotatably supported by the lower portion of the side portion 12 of the frame 1 in the vertical direction of the seat back on a rotation center axis extending in the horizontal direction of the seat back (the horizontal direction in FIG. 1 and the paper direction in FIG. 2). . Further, the crank rod 31 is formed with a mounting portion 32c which is offset from the rotation center axis, that is, the rotation center axis of the sector gear 31c, continuously from one end 32a and the other end 32b via an arm portion 32d. I have.
[0015]
A pair of plates 4 are rotatably supported on the same rotation center axis extending in the left-right direction of the seat back by pins 5 on the upper portions of both sides 11, 12 of the frame 1 in the vertical direction of the seat back. I have.
[0016]
In the above-described configuration, the main body 23 of the spring structure 2 is rotatably supported by the frame 2 by locking the arm portions 21 of the spring structure 2 to the plate 4, and the leg portions 23 are The locking mechanism 32 is connected to the adjusting mechanism 3 by being locked to the mounting portion 32c of the crank rod 32.
[0017]
In addition, the lumbar support device having the above-described configuration is configured to be covered with a cushion pad (not shown) and further covered with a skin (not shown), so that the seat back 6 leans when a seated person is seated. are doing.
[0018]
Next, the operation will be described.
[0019]
When the rotation of the rotating shaft 31b of the operation unit 31 of the adjusting mechanism 3 causes the sector gear 31c to rotate in one direction, the crank rod 32 rotates and the mounting portion 32c moves forward in the seat back thickness direction. Due to the movement of the attachment portion 32c, the spring structure 2 rotates from the position of the dashed line in FIG. 2 to the position of the solid line in FIG. 2 around the rotation center axis passing through the pin 5 (centering on the first predetermined portion 24). (Rotation), the inclination angle of the back support surface 23a in the thickness direction of the seat back is adjusted. As a result, the lumbar support portion 231a of the back support surface 23a of the spring structure 2 is moved forward in the thickness direction of the seat back, and the rotating shaft 31b of the operation unit 31 of the adjusting mechanism 3 is rotated to operate the sector gear 31c. Is rotated in the opposite direction, the crank rod 32 rotates, and the mounting portion 32c moves rearward in the seat back thickness direction. The movement of the mounting portion 32c causes the spring structure 2 to rotate from the position of the solid line shown in FIG. 2 to the position of the dashed line shown in FIG. 2 around the rotation center axis passing through the pin 5 (centering on the first predetermined portion 24). And the inclination angle of the back support surface 23a in the thickness direction of the seat back is adjusted. As a result, the lumbar support portion 231a of the back support surface 23a of the spring structure 2 is moved rearward in the seat back thickness direction. As a result, the degree of support of the lumbar portion of the seated person due to the reaction force generated when the seated person leans on the seat back 6 is adjusted. The reaction force that determines the degree of support of the lumbar portion of the seated person is obtained by the elasticity of the leg portion 22 of the spring structure 2 in the thickness direction of the seat back. Further, since the rotation center line of the spring structure 2 is located between the lumbar vertebra support portion 231a and the thoracic vertebra support portion 232a, that is, the first predetermined portion 24, a large change amount with respect to the adjustment width in the seat back thickness direction. Have gained.
[0020]
As shown in FIG. 3, the spring structure 2 may not include the arm portion 21 extending from the main body 23, and may use the bracket 7 attached to the main body 23 instead of the arm portion 21. In this case, the bracket 7 is directly rotatably supported by the frame 1 by the pin 5 and also serves as the plate 4.
[0021]
As shown in FIG. 3, the spring structure 2 does not include the leg portion 22 extending from the main body 23, and directly connects the lower portion of the main body 23 of the spring structure 2 in the seat back vertical direction, that is, 2 The predetermined part 25 may be the lumbar support part 231a of the spring structure 2. In this case, the spring structure 2 is connected to a crank-shaped torsion bar 8 made of a spring material, and the elasticity of the torsion bar 8 in the thickness direction of the seat back determines the support of the lumbar portion of the seated person. You will gain strength.
[0022]
As shown in FIG. 4, the upper portion of the main body 23 of the spring structure 2 in the vertical direction of the seat back is rotatably supported by the bar 9 or the upper portion 13 disposed in parallel with the upper portion 13 of the frame 1. The center of rotation of the spring structure 2, that is, the second predetermined portion 24, may be the thoracic vertebra support portion 232 a of the spring structure 2.
[0023]
Further, as shown in FIG. 4, the crank rod 32 may be constituted by the leg portions 22 of the spring structure 2.
[0024]
【The invention's effect】
According to the present invention, the above-described technical problem can be achieved, and thereby, a seating sensation for a seated person can be made better than before. In addition to this, the center of rotation of the spring structure is the first predetermined portion located between the lumbar support portion and the thoracic support portion of the back support surface. On the other hand, a large variation can be obtained. In this way, the inclination angle of the back support surface of the spring structure in the thickness direction of the seat back is adjusted, so that an ideal sitting posture can always be obtained.
[Brief description of the drawings]
FIG. 1 is a perspective view of a lumbar support device according to the present invention.
FIG. 2 is a view showing the operation of the lumbar support device according to the present invention.
FIG. 3 is a perspective view showing a first modified example of the lumbar support device according to the present invention.
FIG. 4 is a plan view showing a second modified example of the lumbar support device according to the present invention.
[Explanation of symbols]
1 frame 2 spring structure 3 adjustment mechanism 8 torsion bar (elastic body)
22 Legs (elastic body)
24 First predetermined part 25 Second predetermined part 23a Back support surface 231a Lumbar support part 232a Thoracic vertebra support part

Claims (1)

A spring structure that supports the back of the seated person, a frame that supports the spring structure so as to be rotatable in a seatback thickness direction at a first predetermined portion in a seatback vertical direction, and that the spring structure is the first predetermined portion. is rotated about the site possess an adjusting mechanism for adjusting the inclination angle of the seat back thickness direction of the back support surface of the spring structure, said first predetermined portion includes a lumbar support portion of the back support surface A lumbar support device located between the thoracic spine support site .

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