JP4512892B2 - Chair - Google Patents

Description

  The present invention relates to a chair having a shell serving as a structural member that uniformly supports a load.

Conventionally, in chairs that have a backrest, such as office chairs, that are supposed to be used for a long time, the backrest has a shape with a radius of curvature that increases toward the top to increase the fit when seated. Things are being considered. The reason for adopting such a shape is that the radius of curvature of the human back also increases as it goes upward from the waist. (For example, refer to Patent Document 1.)
JP 2003-189969 A

  However, not only the shape of the backrest fits the back of the seated person, but also when the seater's load is applied to the backrest, the backrest wraps around the back of the seated person, making the seat more fit There is a desire to increase. As an aspect corresponding to such a request, there is also considered a configuration in which the entire backrest is configured to be elastically deformable so that the center part in the width direction of the backrest is retracted when a seated person's load is applied to the backrest. There is a further demand to realize such an effect at a low cost by making the production line and the like common without changing the configuration using the shell used.

  The present invention is configured to solve such problems.

That is, one of the chair according to the present invention, a cushioning material, above the lumbar support portion of the front surface with attached so as to abut without a gap on the rear side of the cushion material serves as a structural member for supporting a load Comprising a shell having a recess at the center in the width direction of the portion, and having a structure in which the thickness dimension of the cushion material at a position corresponding to the recess of the shell in the front view is larger than other portions, The back has a shape in which the curvature radius increases toward the top of the shape of the front surface, and the shell has a shape in which the lumbar support portion projecting forward is seen from the side, and is located above the lumbar support portion. The planar cross-sectional shape of the part is substantially arcuate in plan view, both ends in the width direction of the part project forward, and the front surface of the concave part when viewed in plan cross-section Rate radius smaller than the radius of curvature of the portion below the portion having a concave portion, the projecting recess of the shell is rearwardly, that between the cushion material and the shell has a shape engageable without clearance It is characterized by.

In addition, another one of the chairs according to the present invention plays a role as a structural member for supporting a load by attaching a cushion material having a multi-layer structure and a back surface of the cushion material without any gap. And a shell having a concave portion at the center in the width direction of the portion above the lumbar support portion, and a layer formed of a softer material than the other portions at a position corresponding to the concave portion of the shell in front view of the cushion material And a backrest having a shape in which the radius of curvature increases toward the top of the shape of the front surface, and the shell has a lumbar support portion in front as viewed from the side. In addition to forming an overhanging shape, the flat cross-sectional shape of the part above the lumbar support part is substantially arc-shaped in plan view, and both end parts in the width direction of the part overhang forward. When viewed, the radius of curvature of the front surface of the concave portion is smaller than the radius of curvature of the portion below the portion where the concave portion is provided, the concave portion of the shell protrudes rearward, and there is a gap between the cushion material and the shell. It has a shape that can be engaged with each other.

If it is such, when the seated person leans against the backrest, the portion corresponding to the concave portion in the front view of the cushion material sinks more, and the configuration using the widely used shell is minimal. With this simple configuration, the effect of this backrest fitting on the back of the seated person can be realized at a low cost, and if such a configuration is adopted, there is no gap between the shell and the cushion material. Therefore, the shape of the backrest can be made more stable, and the seated person's back can be held more stably.

Further, the shell has a shape in which the lumbar support part is projected forward in a side view, and the planar cross-sectional shape of the part above the lumbar support part is substantially arcuate in plan view, and both end parts in the width direction of the part are forward Since the curvature radius of the front surface of the recess when projected in a plan view is smaller than the curvature radius of the portion below the portion where the recess is provided, the shell having such a configuration can be realized with a simple configuration.

As one aspect for easily realizing such a chair, the cushion material has a two-layer structure, the rear layer is the soft portion, and the front layer is harder than the soft portion. The thing made into the hard part which is the layer formed with the material is mentioned.

If such a configuration is adopted, the same material and shape as the cushion material used for the conventional backrest can be adopted for the hard part, and a mode in which the soft part is bonded to the back of such a hard part can be adopted. Such a cushioning material can be formed at a low cost by sharing the conventional cushioning material used for the backrest.

  In the present invention, the “layer on the front side of the cushion material” is a layer located on the side close to the back of the seated person, and the “back side of the cushion material” is a layer located on the side far from the back of the seated person. It is the concept which shows.

  In particular, if a configuration in which the soft portion of the cushion material is provided only in a portion facing the concave portion of the shell, the necessary amount of material for forming the soft portion can be reduced. Can be formed at low cost.

Further , if the side cross-sectional shape of the concave portion is a substantially arc shape that recedes backward, the concave portion is depressed to give the seated person a fit, and the back surface of the seated person is held at a portion around the concave portion. Can be realized.

  As a mode for tilting the backrest in conjunction with the seat without impairing the appearance, the backrest formed by attaching the shell to the back frame is pivotally attached to the support base. Used for a chair having a tilting mechanism that tilts in conjunction with each other, wherein the shell serves as a structural member that supports a load applied to a backrest, and has a concave portion on the front surface and is supported by the back frame. What comprises an inner shell and the outer shell which coat | covers this inner shell and the said back frame from back is mentioned.

  In particular, if the outer shell is formed in a shape in which a portion corresponding to the concave portion of the inner shell protrudes rearward, it is possible to indicate to the seated person that this portion sinks further, and the outer shell Since the shape corresponds to the inner shell, the thickness of the outer shell can be made uniform.

One of the chairs according to the present invention has a shell in which the backrest plays a role as a structural member that uniformly supports the load behind the cushion material, and a recess is formed at least above the center in the height direction of the shell. Provided with a structure in which the thickness of the cushion material at a position corresponding to the concave portion of the shell in front view is larger than the other parts, and the curvature radius increases as the shape of the front surface goes upward With a backrest.
Further, another one of the chairs according to the present invention has a shell whose backrest serves as a structural member that uniformly supports a load behind a cushion material having a multilayer structure, and at least the height of the shell. A concave portion is provided above the central portion in the direction, and the thickness of the cushion material at a position corresponding to the concave portion of the shell in a front view is larger than other portions, and the shape of the front surface is directed upward. A backrest having a shape with a larger curvature radius is provided, and a soft portion that is a layer formed of a softer material than other portions is provided at a position corresponding to the concave portion of the shell in front view of the cushion material. And a backrest having a shape in which the radius of curvature increases as the shape of the front surface increases toward the top.
With these configurations, when the seated person leans against the backrest, the portion where the concave portion is formed sinks more, and the configuration using the widely used shell is added with only a minimal change, and a simple configuration Thus, the effect that the backrest fits the seated person's back can be realized at low cost.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  The chair C according to this embodiment is shown in FIG. 1 as a whole perspective view, FIG. 2 as a plan view, FIG. 3 as a right side view, FIG. 4 as a central side sectional view, and FIG. As shown, the chair body 1 that forms the foundation as a structure includes a leg 2 including leg blades 21 and casters 211 with casters 211, a support base 3 attached to the upper end side of the leg 2, and a front part. The chair main body 1 includes a seat receiver 4 supported by the support base 3 and a back frame 5 having a base end attached to the support base 3 and a rear portion of the seat receiver 4 supported at an intermediate portion. A seat shell 61 and a seat cushion material 62 are attached to the seat receiver 4 to constitute a seat 6, and a back shell 71 and a back cushion material 72 are attached to the back frame 5 to constitute a backrest 7. . Further, it further includes a tilting mechanism K that tilts the backrest 7 in conjunction with the seat 6 and a reaction force mechanism H that supplies a reaction force to the back frame 5.

  More specifically, the support base 3 is rotatably attached to the upper end of the leg strut 22 and penetrates the leg strut 22 in the vertical direction, and the bottom wall is inclined obliquely forward and rises. It has a mechanism part storage space that opens upward on the inside, and has a generally boat shape. The support base 3 has a long hole N serving as a slide guide for supporting an axis X1 for connecting to the front end of the seat 6 slidably along the front-rear direction. In addition, the support base 3 has a shaft X3 attached to the back frame 5 penetrating at a position displaced toward the leg column 22 with respect to the shaft X1.

  The seat receiver 4 is located on the support base 3 and extends in the left-right direction in the vicinity of the front end thereof, and a seat 6 including the seat receiver 4 and an axis X1 for rotatably connecting the support base 3 are attached. ing. In addition, this seat 4 is shown with the imaginary line in the figure.

  The back frame 5 includes a pair of left and right back frame elements 51 that extend rearward and upward, a connection member (not shown) that connects the vicinity of the upper ends of these back frame elements 51 with a certain gap, and the back frame. A back shell mounting portion 52 provided at the upper end of the element 51 is provided, and an axis X2 can be installed between intermediate portions of the pair of back frame elements 51. And the lower end part vicinity of each back frame element 51 is rotatably attached to the axis | shaft X3 of the said support base 3, and the rear part of the seat 4 is attached to the axis | shaft X2 constructed between the said back frame elements 51. As shown in FIG.

  The tilt mechanism K adopts a slide engagement structure that slidably engages the long hole N and the shaft X1 attached to the seat receiver 4 in the long hole N formed in the support base 3. Position the axis X1 on the front end side of the long hole N, give the chair C the standing posture where the back frame 5 is raised, position the axis X1 on the rear end side of the long hole N, tilt the back frame 5 backward and sit This is a mechanism in which the rear end of the receiver 4 is depressed to give the chair C a tilted posture, and the backrest 7 and the seat 6 are supported as a whole, and they are tilted in conjunction with each other. The chair C has a lock button (not shown) at the upper end and a gas spring GS having a lower end pivotally attached to the rear end of the support base 3, and is fixed to the upper end of the gas spring GS. And a gas spring fixture GK pivotally attached to an axis X5 provided at a position above the axis X3 of the back frame 5 and, although not shown, pivotally attached to the axis X5 to press the lock button And a lock button pressing operation unit that can be selectively moved to a pressing position to be moved and a spaced position separated from the lock button. When the lock button pressing operation portion is in the pressing position, a lock button (not shown) of the gas spring GS is pressed, and the gas spring GS can be expanded and contracted, and the back frame 5 and the support base 3 The relative position of can be changed. That is, the operation of the tilting mechanism K is permitted, and the tilting of the backrest 7 and the seat 6 is permitted. On the other hand, when the lock button pressing operation portion is in the separated position, the lock button (not shown) of the gas spring GS is not pressed, and the gas spring GS cannot be expanded and contracted, and the back frame 5 and the support base The relative position with respect to 3 cannot be changed. That is, the operation of the tilting mechanism K is prohibited, and the backrest 7 and the seat 6 are fixed.

  The reaction force mechanism H has a pair of coil springs S disposed in a tilted posture inside the support base 3 and supported at the front upper end by a fixed retainer H1, and an axis X4 attached to the lower end of the back frame 5. And a movable retainer H2 attached to the rear end of the coil spring S. The movable retainer H2 supports the rear lower end of the coil spring S, and the shaft X4 moves forward as the back frame 5 is tilted backward. A retainer H <b> 2 compresses the coil spring S and supplies a reaction force to the back frame 5. The fixed retainer H1 can be brought into and out of contact with the movable retainer H2 by a reaction force adjusting mechanism (not shown) so that the reaction force supplied to the back frame 5 can be adjusted.

  The seat 6 serves as a structural member that uniformly supports the load applied to the seat 6 and covers the seat inner shell 611 supported by the seat receiver 4 and the lower portion of the seat inner shell 611 and the seat receiver 4. A seat shell 61 composed of a seat outer shell 612, a seat cushion material 62 provided above the seat shell 61, and a seat cover 63 covering the seat cushion material 62 are provided. In this embodiment, the seat outer shell 612 is located below the support base 3 and covers the lower part of the support base 3.

  The backrest 7 serves as a structural member that uniformly supports the load applied to the backrest 7, and is attached to the back shell mounting portion 52 of the back frame 5 and supported by the back frame 5. And a back shell 71 comprising a back outer shell 712 covering the back of the back inner shell 711, a back cushion material 72 provided in front of the back shell 71, and a back cover 73 covering the back cushion material 72. To do.

  In this embodiment, the back inner shell 711 is provided with a recess 711x at the center thereof, and the back cushion material 72 has a multilayer structure having a hard portion 721 on the front side and a soft portion 722 on the rear side. The rear surface of the soft part 722 is brought into contact with the concave part 711x.

  The back inner shell 711 is the back of FIG. 4, FIG. 5, FIG. 6, which is an overall perspective view from the front side of the back inner shell 711, and the back inner shell 711 attached with the back cushion material 72. As shown in FIG. 7 which is an overall perspective view from the side, the lumbar support portion in a side view is shaped to protrude forward, and the cross-sectional shape is substantially arc-shaped and both widthwise ends are projected forward I have to. In addition, the portion of the back inner shell 711 above the lumbar support portion has a radius of curvature that increases toward the top, and the concave portion 711x has a radius of curvature when viewed in a plan view as the concave portion 711x. It forms so that it may become smaller than the site | part below. Furthermore, the side cross-sectional shape of the recess 711x is formed in a substantially arc shape that recedes backward. The entire front surface of the back inner shell 711 is formed into a smooth curved surface.

  The shape of the back outer shell 712 is attached to a position where the back surface of the back inner shell 711 can be concealed, and plays the role of adjusting the appearance of the chair C. Specifically, it has a shape substantially corresponding to the shape of the back inner shell 711, that is, a shape corresponding to the recess 711x of the inner shell 711 protrudes rearward, and has a substantially uniform thickness dimension throughout. .

  As described above, the back cushion material 72 is formed in a multilayer structure having a hard portion 721 on the front side and a soft portion 722 on the rear side. Here, in the present embodiment, both the hard portion 721 and the soft portion 722 are formed of urethane resin, but a softer one than that used for the hard portion 721 is adopted for the soft portion 722. I have to. Further, in the present embodiment, the shape of the hard portion 721 is the same as that of the cushion material for the backrest having a shape in which the radius of curvature increases toward the upper portion that has been widely used conventionally, and the concave portion in front view. The soft portion 722 is provided only at a position facing the 711x, the soft portion 722 is made to correspond to the concave portion 711x, and there is no gap between the back shell 71 and the back cushion material 72, and these can be engaged. It is molded into a simple shape. Specifically, the thickness dimension of the soft portion 722 is formed into a shape that increases as it goes toward the center in the width direction. Further, the thickness dimension of the entire back cushion material 72 is made larger in the portion facing the concave portion 711x in front view than in other portions.

  When a load is applied to the backrest 7 thus configured, the portion having the soft portion 722 of the back cushion material 72 is elastically deformed in preference to other portions, and the width direction of the front surface of the backrest 7 The central portion is relatively retracted from both ends in the width direction. Then, the back of the seated person is held around the part having the soft part 722, that is, around the concave part 711x. That is, both end portions in the width direction of the front surface of the backrest 7 project relatively forward from the center portion in the width direction, and act so as to wrap up the back surface of the seated person.

  As described above, the backrest 7 of the chair C according to the present embodiment plays a role as a structural member that supports the load, and has the back shell 71 having the recess 711x above the central portion, and the back shell 71. A back cushion material 72 having a hard portion 721 on the front side and a soft portion 722 at a position facing the concave portion 711x of the back shell 71 on the rear side; and the shape of the soft portion 722 The thickness of the entire back cushion material 72 is made to correspond to the shape of the recess 711x of the back shell 71, and the portion facing the recess 711x in front view, that is, the portion facing the recess 711x of the back shell 71 It is larger than other parts. Therefore, when the seated person leans against the backrest 7, a portion where the concave portion 711x is formed sinks more, and an effect of fitting the backrest 7 to the seated person's back can be realized with a simple configuration. Further, since there is no gap between the back shell 71 and the back cushion material 72, the shape of the backrest 7 can be stabilized, and therefore the seated person's back can be held more stably.

  Further, the soft portion 722 is provided only in a portion facing the concave portion 711x, and the hard portion 721 is formed in a shape corresponding to a conventional backrest shape, so that the soft portion 722 is formed. The amount of the material required for this can be reduced, and the hard portion 721 can be made common with the cushion material used in the conventional backrest shape, so that such a cushion material can be formed at a low cost.

  Further, the lumbar support portion in a side view is formed in a shape projecting forward, the flat cross-sectional shape is formed in a substantially arc shape and both ends in the width direction project forward, and the radius of curvature of the arc in the recess 711x is set. Since it is smaller than the lower part of the recess 711x, the back shell 71 having the above-described configuration can be realized with a simple configuration.

  In addition, since the side cross-sectional shape of the recess 711x is formed in a substantially arc shape that recedes backward, the portion corresponding to the recess 711x while holding the back of the seated person at the periphery of the recess 711x That is, the site | part which has the soft part 722 sinks more largely, and a feeling of fitting can be given more effectively to a seated person.

  Further, a chair C provided with a tilting mechanism K that pivotally attaches a back frame 5 to the support base 3 and tilts a backrest 7 formed by attaching the back shell 71 to the back frame 5 in conjunction with the seat 6. The back shell 71 plays a role as a structural member that uniformly supports the load applied to the backrest 7 and is supported by the back frame 5, and the back inner shell 711 and Since the back outer shell 712 covers the back frame 5 from the rear, the back inner shell 712 can cover the back inner shell 711 and the tilting mechanism K, and thus the backrest 7 can be seated without impairing the appearance. It can be made to tilt in conjunction with 6.

  And since the back outer shell 712 has a shape substantially corresponding to the shape of the back inner shell 711, that is, a shape corresponding to the recess 711 x of the inner shell 711, this portion sinks more greatly. You can show this to the seated person.

  The present invention is not limited to the embodiment described above.

  For example, in the embodiment described above, the soft portion 722 may be provided over the entire rear surface of the back cushion material 72.

  Further, a mode in which the front surface of the concave portion of the shell is separated from the rear surface of the cushion material and a gap is provided between them is also conceivable. Even in such a configuration, when the occupant leans against the backrest, the portion where the gap is provided, that is, the portion corresponding to the concave portion of the shell sinks more. Can achieve the effect of fitting to the back of the seated person.

  In this case, a mode in which a plurality of protrusions protruding forward in the width direction are formed on the shell, and a portion between the protrusions is formed as the recess is considered as an example.

  Furthermore, instead of providing the inner shell and the outer shell, one shell having the functions of the inner shell and the outer shell may be provided.

  Moreover, as long as the shape of a recessed part makes the front surface retreat rather than the other site | part of a backrest, you may employ | adopt other shapes, such as forming in a substantially channel shape, for example.

  In addition, if the cushion material is not a two-layer structure, but a soft layer formed of a softer material than other parts of the cushion material is formed at a position corresponding to the concave portion of the shell in front view, 3 A multilayer structure of layers or more may be adopted, and the thickness of the cushion material may be uniform over the entire width as long as such a soft layer is formed. Furthermore, the soft layer is not necessarily provided in contact with the shell on the rear side. That is, as shown in FIG. 8A, a cross-sectional view of the back cushion material and the shell at a position corresponding to FIG. 5 is a two-layered back cushion material a72, with the soft portion a722 on the front side and the hard portion a721 on the front side. It may be provided on the rear side, and the hard layer a721 may be brought into contact with the recess a71x of the back shell a71. Further, as shown in FIG. 8 (b), a cross-sectional view of the back cushion material and the shell at a position corresponding to FIG. 5 is a three-layer cushion material b72 in which hard portions a721 are arranged on both front and rear sides to form a soft portion. You may make it pinch | interpose a722. Furthermore, even if the arrangement shown in FIG. 8B and the arrangement of the hard part and the soft part are reversed, the position corresponding to the central part in the width direction of the back cushion material b72, that is, the concave part b71x of the back shell b71 in front view. Since the thickness dimension is made larger than that of the other portions, at least the portion corresponding to the recess b71x of the front-view back shell b71 can be greatly submerged to fit the back of the seated person. In addition, as shown in FIG. 8C, a cross-sectional view of the back cushion material and the shell at a position corresponding to FIG. 5 is formed in the central portion in the width direction of the back cushion material b72, that is, the concave portion b71x of the back shell b71 in front view. Even if the thickness dimension at the corresponding position is not significantly larger than the other parts, the back cushion material c72 has a multilayer structure, and the center part in the width direction of the back cushion material c72, that is, the concave part of the back shell c71 in front view. If a soft part c722 formed of a material softer than the hard part c721 is provided at a position corresponding to c71x, at least a part corresponding to the concave part c71x of the back-viewed shell c71 is greatly submerged. The effect of fitting to the back can be obtained. 8C, the hard part c721 is formed on the front side and the soft part c722 is formed on the rear side, but the soft part is formed on the front side and the hard part is formed on the rear side. However, if a soft part made of a softer material than the hard part is provided at a position corresponding to the concave part of the front-view back shell, at least a part corresponding to the concave part of the front-view back shell is greatly sunk. It is possible to obtain the effect of fitting the back of the seated person.

  The material of the cushion material is not limited to urethane, and any material may be used as long as it is elastically deformable, such as a gel material or air. Further, different materials may be employed for the hard portion and the soft portion, such as a hard urethane material for the hard portion and a gel material for the soft portion.

  And even if it is the aspect which forms the whole cushion material integrally and makes the thickness dimension of the site | part corresponding to the recessed part of a front view shell larger than another part, at least the site | part corresponding to the recessed part of a front view shell is enlarged. It is possible to obtain the effect of being depressed and fitting to the back of the seated person.

  In addition, various modifications may be made without departing from the spirit of the present invention.

The whole perspective view of the chair which has a backrest concerning one embodiment of the present invention. The top view of the chair which has a backrest which concerns on the embodiment. The right view of the chair which has a backrest which concerns on the embodiment. The center side sectional view of the chair which has the backrest concerning the embodiment. Aa sectional drawing in FIG. The whole perspective view from the front side of the back inner shell concerning the embodiment. The whole perspective view from the back side of the back inner shell concerning the embodiment. Sectional drawing of the position corresponding to FIG. 5 of the back cushion material and back shell which concerns on other embodiment of this invention.

Explanation of symbols

C ... Chair 3 ... Support base 5 ... Back frame 7 ... Backrest 71 ... Back shell 711 ... Back inner shell 711x ... Recess 712 ... Back outer shell 72 ... Back cushion material 721 ... Hard part 722 ... Soft part K ... Tilt mechanism

Claims (7)

A shell having a recess at the center in the width direction of the cushion material and a portion that is attached so as to contact the back of the cushion material without any gap and supports the load and that is above the lumbar support portion on the front surface And has a structure in which the thickness of the cushion material at a position corresponding to the concave portion of the shell in front view is larger than that of other portions , and the curvature radius increases as the shape of the front surface increases toward the top. Comprising a backrest that is shaped as:
The shell has a shape in which the lumbar support part is projected forward in side view, and the planar cross-sectional shape of the part above the lumbar support part is substantially arcuate in plan view, and both end parts in the width direction of the part project forward. The curvature radius of the front surface of the recess when viewed in a plan view is smaller than the curvature radius of the portion below the portion where the recess is provided, the recess of the shell protrudes rearward, and the cushion material and the shell A chair characterized by having a shape that can be engaged with no gap . A cushion material with a multi-layer structure and a structure member that supports the load by being attached so as to contact the back of the cushion material without any gaps, and at the center in the width direction of the part above the front lumbar support part A front surface of the cushion material, and a structure corresponding to the concave portion of the shell is provided with a soft portion that is a layer formed of a softer material than other portions , Comprising a backrest that has a curvature radius that increases toward the top .
The shell has a shape in which the lumbar support part is projected forward in side view, and the planar cross-sectional shape of the part above the lumbar support part is substantially arcuate in plan view, and both end parts in the width direction of the part project forward. The curvature radius of the front surface of the recess when viewed in a plan view is smaller than the curvature radius of the portion below the portion where the recess is provided, the recess of the shell protrudes rearward, and the cushion material and the shell A chair characterized by having a shape that can be engaged with no gap . The cushion material has a two-layer structure, a rear layer is the soft part, and a front layer is a hard part formed of a material harder than the soft part. Item 2. The chair according to Item 2 . The chair according to claim 2 or 3 , wherein the soft portion of the cushion material is provided only in a portion facing the concave portion of the shell. The chair according to claim 1, 2, 3, or 4, wherein a side cross-sectional shape of the recess is formed in a substantially arc shape that recedes backward. A back frame is pivotally attached to a support base, and the back base formed by attaching the shell to the back frame is used in a chair having a tilt mechanism that tilts in conjunction with a seat, the shell being An inner shell that serves as a structural member for supporting a load applied to the backrest and has a recess on the front surface and is supported by the back frame; and an outer shell that covers the inner shell and the back frame from the rear. The chair according to claim 1, 2, 3, 4 or 5 . The chair according to claim 6 , wherein the outer shell is formed in a shape in which a portion corresponding to the concave portion of the inner shell protrudes rearward.

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