JP4919376B2 - Chair with backrest - Google Patents

Description

  The present invention relates to a chair with a backrest.

  There are various types of chairs, and various improvements are made according to each type. As an example, for example, Patent Document 1 discloses a chair in which the seat tilts forward when a seated person leans against the backrest, while Patent Document 2 discloses that the seat is positioned at a substantially middle portion before and after the seated person. There is described a chair that tilts in side view around the center and that the backrest tilts in conjunction with the rear tilting of the seat. Both patent documents employ a kind of link mechanism as means for interlocking the backrest with the seat.

Of those patent document 1, only people seated no change in the attitude with the seat and the backrest, the seat occupant takes a great moment selfish backrest multiplied Re凭the backrest, seat rear portion upward in the principle of leverage are those that push-up is Sagittarius is tilted forward, its purpose is, one in which St. to ensure the comfort state by making it easier stretch the body of the people in the locking state.

On the other hand, in Patent Document 2, for example, when a person sits on the front part of the seat, the backrest greatly tilts forward and pushes the person forward, and the user feels uncomfortable and shifts the sitting position backward. It will be. That is, in Patent Document 2, a so-called “chung (or choi)” that a user sits on the front part of a seat gives a discomfort and a correct sitting posture.
Japanese Examined Patent Publication No. 44-20784 Japanese Examined Patent Publication No.46-27517

  When a person uses a chair, he does not necessarily sit deeply, but often sits shallowly. Since the use of chairs varies from person to person, the design philosophy of the chair also requires a user-friendly idea to keep the user as free as possible even if the sitting position is different (in offices etc. In business, it is common to sit down shallowly). However, the thing of patent document 2 is trying to make the user put the heel which sits down deeply, and it is hard to say that the consideration to the user is enough.

  Moreover, in order to reduce the burden on the body of a seated person, it is important to support the lumbar region. Therefore, in recent years, chairs with lumbar support have become widespread. Since the entire backrest is tilted forward, the lumbar support function cannot be ensured in a shallow sitting state. Furthermore, since a link mechanism is employed as a method for linking the movement of the seat and the movement of the backrest, the number of members is large and the cost is high.

  This invention makes it a subject to improve such a present condition.

The present invention provides a seat for retraction while descending a person is seated, the upper backrest for supporting a portion above the seated occupant's waist, a back frame for supporting the upper seat back, positioned below the upper backrest According to the invention of claim 1, the elastic body whose shape in a side view is changed by a vertical stretching action below the upper backrest. The chair includes a lumbar support portion that can support a lumbar support portion of a seated person. The upper end of the elastic body is attached to the upper backrest or the back frame, and the lower end is attached to the seat, and when the seat moves backward while descending, the elastic body faces forward in a side view. A guide body that is deformed into a convex shape is provided, and the lumbar support portion is configured by a portion of the elastic body protruding forward.

According to a second aspect of the invention, according to claim 1, wherein the elastic member is a resin plate, a lower end of said resins plate is coupled to the rear of the seat so as to Ko傾while descending along with the seat, further, the guide member is disposed below the waist of the person who is seated, by a curved configuration substantially forward concave said guide member in a side view, the said seat body is moved backward while lowering resin The plate is set so as to be bent in a forwardly convex shape in a side view at a position above the seat surface.

Further the third aspect of the present invention, in claim 1 or 2, when a person who is seated leans on the upper backrest, the upper backrest and seat Ru Ko傾Su receding against the spring means.

Incidentally, the elastic body in the present invention is forward projected does not mean that the whole of the elastic body is forward protruded, by deformation of the elastic body, in the sense that portion corresponding to the human out of the elastic body is moved forward is there.

In the chair of the present invention, when a person sits down, the lumbar support part protrudes forward, so even if a person sits shallowly on the seat, the seated person's waist is supported from behind by the lumbar support part . For this reason, even in the shallow sitting state as so-called Chung-seat, it can significantly reduce the burden on the user's body.

In addition, since the lumbar support portion is configured by utilizing deformation of an elastic body, the number of members is small and the structure is simple. Therefore, the cost can be suppressed and the design can be refreshed. Further, in the interlocking mechanism using the link mechanism, when a person leaves the seat and the load is lost, a spring means for returning the seat and the backrest to the neutral state is necessary. In the present invention, the elasticity of the elastic body constituting the backrest is required. Since the seat and the elastic body can be returned to the neutral state by the restoring force, it is possible to eliminate the need for the dedicated spring means, and this aspect can also contribute to simplification of the structure and cost reduction.

Further, sufficient in the lower end of the elastic body only connected to the seat, for special interlocking member is not required, Ru can the structure more easily.

  According to the third aspect of the present invention, the locking function can be maintained in a state where the waist is accurately supported regardless of the seating position, which is particularly preferable.

  Next, an embodiment of the present invention will be described with reference to the drawings. The present invention is applied to a rotary chair for office use or the like.

(1). First embodiment (FIGS. 1 to 5)
1 to 5 show the first embodiment. 1 is a separated side view of the chair, FIG. 2 (A) is a side view of the chair, (B) is a partially enlarged view of (A), (C) is a partial sectional view of (A), 3 is a side view showing the movement, FIG. 4 is a partially broken schematic front view with the members separated, and FIG. 5 is a cross-sectional view taken along the line VV in FIG.

  The chair includes a leg support 1 made of a gas cylinder, a seat receiving base 2 fixed to the upper end thereof, an intermediate member 3 attached to the seat receiving base 2, a seat 4 attached to the intermediate member 3, and a seat receiving base 2. A back frame 5 connected to be freely tiltable rearward and a backrest 6 supported by the back frame 5 are provided.

The backrest 6, the upper backrest 7 fixed to the top of the back frame 5, and a placement lower backrest 8 thereunder. The back frame 5 includes left and right arms 9 constituting the front portion thereof and left and right back struts 10 attached thereto, and an upper backrest 7 is fixed to the upper portion of the back strut 10. Although not shown in the drawings, the leg support 1 is attached to a leg base having a plurality of branch branches extending radially, and each branch branch is provided with a caster.

The seat base 2 is formed in a box shape opened upward, and the intermediate member 3 is connected to the front portion thereof by a first shaft 11 that is long in the left-right direction. The intermediate member 3 includes left and right side plates 3a positioned on the left and right outer sides of the seat receiving base 2 in plan view, and front and rear connecting members 3b that connect the left and right side plates 3a. The front connecting member 3b includes a seat receiving base. The front bracket plate 3c adjacent to the outer surface of the second plate 2 is fixed by welding or the like, and the first shaft 11 passes through the front bracket plate 3c and the seat base 2. As clearly shown in FIG. 1, the insertion hole of the first shaft in the seating base 2 is a long hole 12 extending rearwardly in a side view, so that the first shaft 11 extends along the long hole 12. Can slide. A resin bush 13 is mounted in the long hole 12.

Arm 9 of the back frame 5 is linked seat receiving extends rearwardly along the outer surface of the base 2 Biteori, the front and rear intermediate portion of the tip portion and the seat receiving the base 2 of the arm 9 in the second axis 14. In addition, the left and right rear brackets 3d fixed to the rear connection member 3b of the intermediate member 3 and the front and rear middle portions of the arm 9 are connected by a third shaft 15 that is long in the left and right direction. Therefore, the intermediate member 3 and the back frame 5 move backward while tilting in conjunction with each other. Although not shown, a spring that supports the backward movement of the first shaft 11 is disposed inside the seat receiving base 2, and the backrest 6 is locked against this spring.

As shown in FIGS. 2C and 4, the seat 4 has a structure in which a cushion is stretched on the upper surface of a seat inner shell 4a made of resin or the like. And while attaching the guide roller (roller) 17 (it may be a slider) which has a left-right longitudinal rotating shaft to the front-and-rear both ends of the right-and-left side board 3a in the intermediate member 3, on the left-right both sides and two front-and-rear positions A plate-like support member 18 made of a resin (or metal) located on the outer surface of the intermediate member 3 is disposed at a portion of the intermediate member 3, and the guide is inserted into the guide hole 19 inclined in a side view when formed on the support member 18. A roller 17 is fitted.

Therefore, the seat 4 can be retracted while descending without changing the posture in side view. In other words, the robot can move backward while descending while maintaining a substantially horizontal posture without tilting forward or backward. As shown in FIG. 4, the left and right support members 18 are fixed to the seat 4 via a reinforcing plate 20 made of a metal plate. Therefore, while allowing deformation of Zai N'nasheru 4a, the support member 18 can smoothly slide without causing entanglement. It is also possible to provide the support member 18 on the intermediate member 3 and the roller 17 on the seat 4.

The upper backrest 7 has a structure in which a cushion is stretched on the front surface of the back inner shell (the cushion may not be provided). On the other hand, the lower backrest 8, a resin plate such as polypropylene as an example of an elastic member provided with a (lower inner shell) 21, forms a portion corresponding to a human of the resin plate 21 and the lumbar support section, on the front of its Has a cushion 22. Of course, it is possible to have no cushion, and it is also possible to stretch a rubber material such as an elastomer as means for softening the contact with a person. Moreover, it is also possible to use a metal plate such as a leaf spring instead of the resin plate 21 as the elastic body .

  As clearly shown in FIG. 2B, the upper end of the resin plate 21 is attached to a support body 23 provided on the back surface of the lower end portion of the upper backrest 7 via a hinge 24. Therefore, the resin plate 21 can be easily rotated back and forth around its upper end. The support portion 23 may be integrally formed with the inner shell of the upper backrest 7 or may be separate from the inner shell. Further, the upper end of the resin plate 21 may be attached to the back column 10.

The lower end (more precisely, the lower end portion) of the resin plate 21 is attached to the rear lower surface of the seat 4. That is, as best shown in FIG. 2 (C), the attached right and left longitudinal rods 26 to the wood N'nasheru 4a lateral plurality of bearing portions 25 formed on the lower surface of, winding a lower end portion of the resin plate 21 to the rod 26 Thus, the lower end portion of the resin plate 21 is formed in a cylindrical shape and the state is held with screws. For this reason, the lower end portion of the resin plate 21 can be easily rotated around the rod 26. Needless to say, the lower end of the resin plate 21 may be fixed to the lower surface of the seat 4 with screws or the like. Alternatively, it can be fitted (locked) from the rear into a rearward-facing engagement hole provided in the lower surface of the seat 4.

  The horizontal width dimension of the resin plate 21 is set to be slightly smaller than the lateral width of the seat 4, while the rod 26 is positioned between the left and right support members 18. For this reason, the lower end portion of the resin plate 21 is formed with a small width so as not to be buffered with the rear support member 18.

  There is a considerable gap between the rear end of the seat 4 and the back column 10 in the non-sitting state. Further, a guide body 28 having a guide surface 27 that is curved obliquely upward so as to look up at the rear end of the seat 4 in a side view is fixed to the back column 10. The guide body 28 is made of resin, and is fixed to the left and right back posts 10 by screws or the like as shown in FIG. Note that the guide body 28 may be integrally provided on the back column 10.

  A block-shaped multiple-stage deformation restricting body 29 is fixed or integrally formed on a portion of the back surface of the resin plate 21 located in the concave portion of the guide body 28 in the non-sitting state. The deformation restricting body 29 is located between the left and right guide bodies 28. For this reason, the deformation restricting body 29 also functions to prevent the resin plate 21 from shaking left and right. A portion of the resin plate 21 provided with the deformation restricting body 29 is deformed into a forward concave shape but is not deformed into a forward convex shape.

  A portion of the resin plate 21 between the upper end and the guide body 28 is curved in a slightly forwardly convex shape in a side view. This is to give the directionality of the resin plate 21 protruding forward when a person is seated. The guide body 28 may extend to the upper end portion of the resin plate 21.

  As shown in FIG. 4, the lower ends of the left and right back struts 10 are connected to the connecting plate 30, and the left and right shaft bodies 31 provided on the connecting plate 30 are inserted into the rearward holes of the arm 9 from the rear. Yes. Further, the left and right back struts 10 are connected to each other at the upper part by a horizontal rail. Although the back column 10 is formed in a plate shape, the shape can be arbitrarily set such as a round or square pipe shape or an L-shaped cross section. The back frame may be a resin molded product. Further, a cover for covering the back frame 5 from behind may be provided.

In the above configuration, when a person is seated, the seat 4 moves down without changing its posture in side view, and the lower end of the resin plate 21 faces the lower end of the guide body 28 as the seat 4 moves. Pushed out. Then, since the vertical length of the resin plate 21 is not changed, the resin plate 21 has a forward convex shape at a portion above the guide body 28 as shown in FIG. 3 by the guide action of the curved guide surface 27 in the guide body 28. prospectively projected with curved, forwardly projecting portion becomes lumbar support section. Thereby, even if a person sits shallowly on the seat 4, the lumbar support function can be exhibited by accurately supporting the waist of the person with the resin plate 21.

  In this case, by providing the deformation restricting body 29 on the resin plate 21, the portion of the resin plate 21 on which the deformation restricting body 29 is provided is held in a substantially linear state when viewed from the side. It is ensured that the projection protrudes in a forward convex shape, and the shape curved in the forward convex shape does not collapse even when human body pressure acts on the resin plate 21. That is, the resin plate 21 is bent in a constant state by the deformation restricting body 29, and the curved shape is held constant.

  Even if a person sits deeply on the seat 4, the resin plate 21 protrudes forward by the same amount, but the resin plate 21 has flexibility, so it does not feel a pressure even when seated deeply. The board 21 fits tightly to the waist.

  As a means for ensuring an appropriate fit even if a person sits deeply or sits shallowly, the amount of protrusion of the lower backrest 8 may be automatically adjusted according to the seated state. As means for that purpose, the following can be considered in addition to the deformation of the resin plate 21 in plan view.

  That is, (a). As indicated by a dotted arrow A in FIG. 3, the upper end of the resin plate 21 is supported by spring means (not shown) so that the upper end of the resin plate 21 moves away. (B) Contrary to a, the spring means is disposed between the lower end of the resin plate 21 and the seat 4 to release the resin plate 21 below the seat 4. Thus, when a certain amount of resistance is applied, the resin plate 21 is not deformed even if the seat 4 is slid. (C) As shown by a dotted arrow B in FIG. It is attached to the back frame 5 in a state where it can be tilted backward, and the backward movement or backward tilt of the guide body 28 is supported by a spring means, so that the resin plate 21 does not move forward when a certain pressing force is applied. ). There is external force at an appropriate part of the resin plate 21 other than the part that hits the person's waist. A buffer portion that is deformed into a convex shape or a zigzag shape when viewed from the side is provided.

  When a person leans on the backrest 6 with the seat 4 sliding backward, the backrest 6 tilts backward as a whole, and the intermediate member 3 and the seat 4 tilt backward slightly while moving backward. That is, the person's waist is locked while maintaining the state of being accurately supported by the resin plate 21, and this is an advantage of the present embodiment that is not found in the prior art. Further, since the seat 4 slides without changing the posture in side view, the user can take a proper working posture in a non-locking state. This is also an advantage of this embodiment.

(2). Other Embodiments FIG. 6 shows another embodiment. Among these, in (A), plate-shaped ribs 32 for restricting deformation are integrally formed on the resin plate 21. In the third embodiment (B), the as means for bending the resin plate 21 in a predetermined shape, according to the areas of the apex of the lumbar support portion in the side view of the resin plate 21 is thinnest in distance vertically from the vertex The thickness is set to be thick. Furthermore, in 4th Embodiment shown to (C), in order to make it easy for the resin board 21 to bend and deform | transform into a forward concave shape by planar view, the longitudinal strip 33 is arranged in multiple numbers in the resin board 21 in parallel.

The lumbar support portion does not necessarily need to be made of a resin plate. For example, as shown in FIG. 6D as a fifth embodiment, a plurality of rod-like (or belt-like) elastic bodies 34 extending in the vertical direction are arranged, and a contact plate 35 is attached to the front surface of the elastic body 34. Is also possible. Needless to say, the elastic body 34 is deformed into a state in which the elastic body 34 is curved in a forward convex shape in a side view, like the resin plate 21 of the first embodiment. The elastic body 34 may be made of resin or metal such as a leaf spring.

Sixth embodiment shown in FIG. 7 is a modification of the first embodiment, in this embodiment, the backrest 6 is provided with a synthetic resin of the back inner shell 36 extending series vertically, the back inner shell 36 The upper inner shell 36a constituting the upper backrest 7 is a non-deformed portion fixed to the back frame 5 and has an upper cushion 22 'stretched thereon, while the lower inner shell 36a is located below the upper inner shoulder 36a. The shell 36b is a deformation allowing portion that can be largely deformed by sitting, and a part of the lower inner shell 36b is configured as a lumbar support portion. The operation of the lower inner shell 36b is the same as that of the resin plate 21 of the first embodiment.

  In order to ensure that the lower inner shell 36b bends forward and deforms due to the seating, a stopper 28 'for supporting the upper end of the lower inner shell 36b from the rear side may be provided as shown by a one-dot chain line. Although it has been described that the upper inner shell 36a is a non-deformable part, the "non-deformable part" here means that it does not deform even if a person is seated. It can be deformed. It is also possible to integrate the inner shell 36 of the backrest 6 and the inner shell of the seat 4.

(3). Other Variations Although not shown, the present invention can be further expanded into various variations. For example, the deformation amount of an elastic body such as the resin plate 21 can be adjusted. As a specific adjusting means, taking the resin plate 21 of the first embodiment as an example, the mounting position of the upper end or the lower end of the resin plate 21 can be adjusted, or the resin plate 21 can be adjusted after the seat 4 starts to slide. It may be possible to adjust the distance until the tension force is applied.

The mechanism for sliding the seat is not necessarily limited to the combination of a roller (or pin) and a long hole, and various mechanisms such as a parallel link mechanism and a rail mechanism can be adopted. If not small, the amount of sliding of the seat, by providing an amplifying means which applies the principle of the lever or the like, can I increase the amount of deformation of the elastic body. It is also possible to form the entire backrest with an elastic plate such as a resin plate. However, also in this case, it is set so that the portion (lumbar support portion) that hits the human waist protrudes greatly forward .

It is a separation side view of the chair concerning a 1st embodiment. (A) is a side view of a chair, (B) is a partial enlarged view of (A), and (C) is a partial cross-sectional view of (A). It is a side view which shows a movement. It is the partially broken schematic front view which isolate | separated the member. FIG. 5 is a VV sectional view of FIG. It is a figure which shows other embodiment. It is a figure which shows other embodiment.

1 leg support 2 seat receiving base 3 intermediate member 4 seat 5 back frame 6 backrest 7 upper backrest 8 lower backrest (lumbar support part)
DESCRIPTION OF SYMBOLS 10 Back support | pillar 17 Roller which comprises slide means 18 Support member which comprises slide means 21 Resin board (lower inner shell) as an example of elastic body
22 Cushion 28 Guide body

Claims (3)

A seat for human retraction while descending and seated, and an upper backrest for supporting a portion above the seated occupant's waist, a back frame for supporting the upper back, sitting positioned below the upper backrest A chair provided with a lumbar support portion capable of supporting a human waist ,
Below the upper backrest, an elastic body whose side view shape is changed by a vertical stretching action is arranged, the upper end of the elastic body is attached to the upper backrest or the back frame, and the lower end is attached to the seat. The back frame is provided with a guide body that deforms the elastic body into a convex shape in a side view when the seat moves backward while descending, and the lumbar support portion is configured by a portion protruding forward of the elastic body. Being
Chair with backrest. The elastic body is a resin plate, a lower end of said resins plate is coupled to the rear of the seat so as to Ko傾while descending along the seat, further, the guide body than the waist of the person seated have also been arranged below the guide member by a curved configuration substantially forward concave in a side view, a side view in a position above the resin plate seating surface and retracts the seat body being lowered Is set to curve in a forward convex shape,
A chair with a backrest according to claim 1. When seated occupant leans on the upper back, Ko傾Su Ru receding upper backrest and seat against the spring means,
A chair with a backrest according to claim 1 or 2.

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