JP4208027B2 - Chair - Google Patents

Description

  The present invention relates to a chair that can contribute to an improvement in sitting comfort, and particularly relates to a chair that is suitably used mainly in the office automation field such as an office.

  Conventionally, various ideas have been made for the purpose of improving the sitting comfort of a chair. For example, the lower part of the backrest surface is partially protruded forward to form the lumbar support part. The reason for this is that the lumbar support part has a shape that supports the lumbar part of the seated person, thereby providing a comfortable and stable sitting comfort.

  By the way, if this part has a uniform shape, depending on the physique and how to sit, the seated person's waist may not be supported stably, and some people may be dissatisfied with the sitting comfort. obtain.

  Accordingly, the present invention has been made to solve the above problems and to provide a chair that is extremely excellent in sitting comfort.

That is, the chair according to the present invention supports the back support rod, the tension member that forms the lower portion of the backrest surface, the right and left side edges and the lower end of the tension member, and the center of rotation at the upper portion of the back support rod. Ri Na and and a set support frame, the support frame is characterized by projecting the said back surface lower forward by projecting forwardly rotated.

In addition, the lower portion of the backrest surface may be moved back and forth by the forward / reverse rotation operation of the support frame.

In addition, a drive mechanism for adjusting the position of the support frame is provided, and the drive mechanism can be locked in a state where the support frame is at least returned to the protruding state .

As a preferred embodiment, the lower part of the backrest surface functions as a part of a lumbar support part that can support the lumbar part of a seated person, or the tension member is not attached to the back support rod via the cushion material or the like. A mode in which the tension is provided may be mentioned.

  Further, as shown in FIG. 5, a mode in which the rotation center X is set to the back 5 and the lumbar support portion LS is positioned below the rotation center X is also conceivable.

  Note that “moving back and forth” means moving including at least the front-rear direction.

  According to the present invention, it is possible to provide a chair that is extremely excellent in sitting comfort.

  An embodiment of the present invention will be described below with reference to the drawings. Note that members corresponding to those described in “Means for Solving the Problems” are denoted by the same reference numerals.

  FIG. 1 is a perspective view showing a main part of a chair 1 showing an embodiment of the present invention. The chair 1 includes a base leg 2, a support base 3 attached to the base leg 2, and a seat 4 and a back 5 supported by the support base 3 via a four-side link mechanism 6. By the action of the four-side link mechanism 6, when the back 5 is rocked backward, the seat 4 is moved backward accordingly.

  The support base 3 has a long shape, and is arranged so that its lower end is fitted and fixed to the upper end of the column 21 constituting the base leg 2 and extends obliquely forward.

  The seat 4 is configured such that the seating surface is slidable back and forth with respect to the seat receiver 41. More specifically, a cushion or the like is mounted on the seat receiver 41 so as to be slidable back and forth through a slide mechanism (not shown).

  The back 5 is formed by stretching a tension member 52 on the back support rod 51, and does not have a cushion material or the like, and the cushioning property is exhibited by using the tension of the tension member 52. The back support rod 51 includes an upper frame 511 that is a part mainly corresponding to a backrest surface, and a lower frame 512 positioned below the seat support 41. The upper frame 511 and the lower frame 512 are horizontally arranged. A depressing mechanism (not shown) that can be pivotably connected to each other via a support shaft S1 extending in the left-right direction and that can deter the rotation is provided. This deterrent mechanism, for example, is configured to fix the upper frame 511 and the lower frame 512 by inserting a pin between them so that the upper frame 511 and the lower frame 512 cannot be rotated. Used in a rotatable mode in which the lower frame 512 can be rotated with respect to each other and only the upper frame 511 can be tilted, and in a non-rotatable mode in which these are fixedly coupled to each other and the entire back support rod 51 can be locked. Can be switched.

  As shown in FIG. 2, the four-side link mechanism 6 rotatably couples the end portions of the four link members 61 to 64 via support shafts S1 to S4. It is to be formed. Specifically, the support base 3 serves as the lower link member 61, the seat frame 42 serves as the upper link member 62, and the backrest lower frame 512 serves as the rear link member 63. A dedicated front link member 64 is arranged between the sections.

  In this embodiment, as shown in FIG. 3 in particular, the tilting body 7 is provided behind the seat frame 42, and the rear end portion of the cushion and the like constituting the seating surfaces 4a and 4b is supported on the tilting body 7 from below. In addition, a support frame 10 that constitutes a lumbar support portion is integrally provided at the rear end of the tilting body 7, and a tension member 52 that forms a lower backrest surface 5 b is supported on the support frame 10. Then, the tilting body 7 and the support frame 10 that are integrated with each other are moved via the drive mechanism 11 by the operation of the operation lever 8 that is the operation unit, and the back seat boundary portion that includes the seating surface rear portion 4b and the backrest surface lower portion 5b. K can be deformed.

  If each part is explained in full detail, the tilting body 7 is a pair of left and right frames extending in the front-rear direction, and also serves as a support arm. And it is made to support by the back support rod 51 through the support mechanism 9 so that a position change is possible. The support mechanism 9 is configured to rotatably couple the tilting body 7 to the lower frame 512 via the support shaft S1 at the front end portion thereof. And by this tilting body 7, the seating surface rear part 4b lifts the rear end part further from the lower position P (shown by a two-dot chain line in FIG. 3) which is substantially flush with the seating surface front part 4a. Further, it is supported so as to tilt with respect to the upper position Q.

  On the other hand, the drive mechanism 11 that drives the tilting body 7 rotates one end of the gas spring 111 that is an elastic member whose length can be freely changed to the back support rod 51 (more specifically, the lower frame 512) that is a support member. While being fixed movably, the other end is rotatably fixed to a part displaced from the tilting fulcrum X of the tilting body 7. Then, the operation lever 8 provided on the lower surface of the seat 5 and the operation portion 111a of the gas spring 111 are connected by a link wire LW, and the operation of the operation lever 8 allows the gas spring 111 to expand and contract freely. It is possible to switch to a locked state where the length is fixed. Further, when the gas spring 111 is in a free state, a force that moves forward to the tilting body 7 by the extension force is always applied.

  The support frame 10 is a frame-like frame formed by bending at a substantially right angle from the rear end of the tilting body 7 and extending integrally as viewed from the side, and supports the left and right side edges of the tension member 52 that forms the backrest lower portion 5b. . Then, as the tilting body 7 moves from the lower position P to the upper position Q, it protrudes forward, and the backrest surface lower portion 5b is protruded forward while increasing the tension of the tension member 52 of that portion. The lumbar support portion includes the pair of support frames 10 and a tension member 52 stretched between them. A bent portion 101 that is bent in an arc shape toward the rear is formed at the distal end portion of the support frame 10 to improve the sense of hitting the hipbone. In the non-rotatable mode in which the upper frame 511 and the lower frame 512 are fixedly coupled to each other, when the tilting body 7 is set at the lower position P, the tilting body 7 is at a position where a normal backrest surface is formed. In the position where the tilting body 7 is moved to the upper position Q side rather than the lower position P in the non-rotatable mode, it is set so as to protrude forward by that amount.

  In the chair 1 according to the present embodiment having such a configuration, when the positions of the tilting body 7 and the support frame 10 are adjusted, the operation lever 8 is first operated to make the gas spring 111 free. Then, the tilting body 7 and the support frame 10 are operated in the backward tilting direction against the extension force, and when the desired angle is reached, the operation lever 8 is operated in the opposite direction so that the gas spring 111 is locked, and the tilting body 7 And the support frame 10 is fixed so that the angle cannot be changed. More specifically, the position adjustment may be performed while the seated person leans on the back 5.

  Therefore, according to the present embodiment, the back seat boundary portion K is moved or deformed regardless of the physique or sitting method of the individual occupant, and the pelvic angle of the occupant or along the lumbar region of the occupant. Therefore, it is possible to provide the chair 1 which is extremely excellent in sitting comfort.

  Further, in this embodiment, the tension of the tension member 52 that forms the backrest surface lower portion 5b increases as the support frame 10 projects forward, so that the backrest surface lower portion 5b projects forward. In this case, a tension is given to the lower back surface 5b, which can contribute to the improvement of the sitting comfort.

  In addition, this invention is not limited to the Example mentioned above.

  For example, as shown in FIG. 4, in a state where the gas spring 111 is free, the tilting force may be applied to the tilting body 7 by the extension force. In this case, in order to adjust the positions of the tilting body 7 and the support frame 10, first, the operation lever 8 is operated to release the gas spring 111. Then, the tilting body 7 and the support frame 10 are operated in the forward tilt direction against the extension force, and when the desired angle is reached, the operation lever 8 is operated in the opposite direction so that the gas spring 111 is locked, and the tilting body 7 And the support frame 10 is fixed so that the angle cannot be changed. In this figure, the same reference numerals are given to members corresponding to the above-described embodiment.

  Further, as in the above embodiment, the tilting body 7 can be fixed steplessly between the upper position Q and the lower position P. In addition, for example, using a ratchet mechanism, the tilting body can be fixed at a plurality of predetermined positions. It may be possible to fix in stages.

  In addition, the present invention can be applied not only to the above-mentioned rocking chair but also to a back-seat-fixed type chair that cannot be rocked, or to a seat that does not have a back so that the back of the seating surface can be inclined. The effects of can be achieved.

The fragmentary perspective view which shows the internal basic structure of the chair in one Example of this invention. The schematic side view which shows especially the four-sided link structure of the chair in the Example. The partial schematic sectional side view which mainly shows the tilting body and lumbar support part in the Example. The fragmentary sectional side view mainly showing a tilting body and a lumbar support part in another embodiment of the present invention. A side view showing typically an example of a chair concerning the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Chair 51 ... Back support rod 5b ... Backrest lower part 52 ... Tension member 10 ... Support frame 11 ... Drive mechanism LS ... Lumber support part

Claims (5)

With back support,
A tension member that forms a lower portion of the backrest surface and exhibits cushioning properties without using a cushion material or the like by using the tension of the backrest surface;
A tension member that forms a lower part of the backrest surface is stretched to support left and right side edges and a lower end of the tension member, and a support frame having a center of rotation set at the upper part of the back support rod. ,
The support frame rotates and protrudes forward so that the tension member forming the lower portion of the backrest surface is protruded forward. The chair according to claim 1, wherein the lower portion of the backrest surface is moved back and forth by forward and reverse rotation operations of the support frame. The chair according to claim 1 or 2, further comprising a drive mechanism for adjusting a position of the support frame, wherein the drive mechanism can be locked at least in a state where the support frame is returned to a protruding state. The chair according to claim 1, 2 or 3, wherein the lower part of the backrest surface functions as a part of a lumbar support part that can support a waist of a seated person. The chair according to claim 1, 2, 3, or 4, wherein the tension member is stretched on the back support rod without the cushion material or the like interposed therebetween.

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