JPH0779746B2 - Chair with backrest - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chair with a backrest, and more particularly to a chair with a backrest in which an upper side of a backrest portion tilts rearward with respect to a lower side.

(Prior Art) As a chair with a backrest in which the upper part of the backrest tilts backward, the chair shown in FIG. 6 is generally used.

In the chair shown in FIG. 6, the back plate portion and the seat portion are connected by a back support rod, and the back plate portion rotates around the tip of the back support rod that is located at approximately the center of the back plate portion. 6 (a), or the entire back plate tilts rearward at a uniform angle [FIG. 6 (b)].

Further, a chair that can use the operations shown in FIGS. 6 (a) and 6 (b) together is also widely used.

Then, in the stool, the seating reference point (Y in FIG. 6), which is the center point of the load applied to the seat, and the backrest point (X in FIG. 6), which is the center point of the load applied to the backrest, are provided. Existing.

In addition, the Katsushi sitting reference point and the backrest point are JIS-S-10
It can be determined according to Table 1 of 11.

(Problems to be Solved by the Invention) In the chair shown in FIG. 6, the backrest point X when the chair is in the original state (hereinafter referred to as the standard state) causes the back plate portion to rotate as shown in FIG. Or, when it is tilted rearward, its position becomes X ', and the linear distance between the backrest point and the sitting position reference point is the back plate portion rotated or tilted with respect to the linear distance A in the standard state. In this case, the straight line distance B is enlarged as shown in FIG.

By the way, it is generally said that the backrest point should be located slightly above the user's belt when the user sits down on the chair, which can minimize the user's fatigue. There is.

However, even if the backrest point is adjusted to the ideal position in the chair in the standard state, when the user leans his back against the backboard portion and pivots or tilts the backboard portion backward, The point moves above the back of the user in relation to the user and deviates from the ideal position for the user, which gives the user a feeling of discomfort.

Moreover, when the user repeats the operation of leaning his back on the back plate or raising his back, the shirt or the like worn by the user is tucked up and its hem protrudes from the pants or the like. Sometimes.

Therefore, an object of the present invention is to keep the backrest point at an ideal position for the user even if the backboard portion or the backboard portion and the back support rod (hereinafter referred to as the backrest portion) are rotated or tilted rearward. (EN) It is possible to provide a chair with a backrest that can be worn and in which a worn shirt or the like cannot be tucked up.

(Means for Solving the Problem) A drawback of the conventional chair with a backrest described above is that, when the backrest portion is rotated or tilted, the position of the backrest point in the backrest portion can move downward in accordance with the movement of the backrest portion. It can be solved by the chair of the present invention having the following configuration.

That is, according to the present invention, in a chair with a backrest in which the upper side of the backrest can be tilted rearward with respect to the lower side, the chair has elasticity that connects the vicinity of the rearward tilting base on the upper side of the backrest and the rear of the seat. A belt-like body is provided, and a portion extending downward from a connecting portion to the backrest portion of the belt-like body is formed in a curved portion that protrudes shallowly forward, and an upper side of the backrest portion is a lower side. A chair with a backrest, wherein the curved portion projects forward with respect to a lower side of the backrest portion by tilting backward.

In such a chair with a backrest, the rigidity of the curved portion of the strip is higher than that of the lower portion, and the tip of the back support rod is located near the curved portion of the strip, and the back support rod is The upper part of the backrest is tilted backward with the tip of the belt as a fulcrum, the vicinity of the connection part of the strip to the backrest is thicker than other parts of the strip and / or is reinforced by attaching ribs. That is, when the upper side of the backrest is tilted rearward with respect to the lower side, the curved portion of the belt-like body can be easily projected forward.

Further, the belt-shaped body between the curved portion and the seat portion is bent in a bellows shape in the longitudinal direction of the belt-shaped body, so that the amount of protrusion of the curved portion toward the front can be adjusted.

Further, the belt-shaped body integrally formed with the backrest portion makes it possible to easily manufacture the chair with a backrest according to the present invention.

In the present invention, "to tilt the upper side of the backrest rearward with respect to the lower side" means that the tip of the backrest can be tilted rearward more than the lower end thereof, and only the upper end of the backrest is required. Includes an operation of tilting backward, an operation of tilting the upper end portion and the lower end portion of the backrest portion rearward at a uniform angle, or an operation that combines both operations.

(Operation) In the chair with a backrest shown in FIG. 6 which has been generally used conventionally, the position of the backrest point in the backrest portion tilts the upper side of the backrest portion with respect to the lower side (hereinafter, simply referred to as tilting). ) It is constant before and after.

Therefore, the linear distance between the seating reference point and the backrest point (hereinafter referred to as the distance) increases as the backrest tilts, and the position of the backrest point moves above the user's back in relation to the user. To do.

In this regard, according to the chair of the present invention, since the curved portion of the belt-like body that connects the vicinity of the tilting base portion of the backrest portion and the rear portion of the seat portion projects forward as the backrest portion tilts, the backrest point on the bending portion. When is located, the position of the backrest point on the curved portion moves downward, and the distance between the backrest point and the sitting position reference point can be kept as constant as possible regardless of the state of the backrest portion. As a result, the position of the backrest point in relation to the user can be maintained at an ideal position for the user, and the shirt or the like worn by the user cannot be tucked up.

Embodiment An embodiment of the present invention will be described with reference to the drawings.

1 and 2 show an embodiment in which the present invention is applied to a chair in which the internal mechanism of the chair is covered by a shell structure composed of two shell members.

In the figure, 1 is a backrest part, 2 is a seat part, 3 and 4 are shell members constituting a shell structure of a chair, and 5 is a cushion part.

In this embodiment, as shown in FIGS.
And a shell member 3 (hereinafter, referred to as an outer shell) that forms a rear portion of the backrest 1, and a shell member 4 (hereinafter, referred to as an outer shell) that is in contact with the shell structure. The internal mechanism shown in FIG. 2 is provided inside.

In this internal mechanism, a back support rod 76 is attached to a rear end portion of a fixing plate 81 provided on an upper portion of a pillar 70 so as to be tiltable rearward about a shaft 73.

The back support rod 76 is supported by a spring (not shown), and the user leans deeply on the backrest portion 1 and tilts rearward against the biasing force of the spring.

The spring also functions as a return spring.

The shell structure is an outer shell 3 and an inner shell 4.
Are integrally assembled by a locking tool arranged along the outer periphery thereof and substantially encapsulate the internal mechanism.

That is, the shell structure is fixed to the upper surface of the fixing plate 81 on the lower surface of the corresponding inner shell 4 with the screw 80 or the like, and the back support rod 76 is inserted into the space of the shell structure on the backrest part side up to the middle part. ing.

On the other hand, a portion of the outer shell 3 corresponding to the fixed plate 81 is cut out.

In the chair according to the present embodiment, the entire backrest portion 1 can be tilted rearward, and the upper side of the backrest portion 1 can be further tilted rearward with respect to the lower side.

That is, the shell structure corresponding to the backrest can be tilted rearward as a whole, and the upper side of the shell structure can be elastically bent around the vicinity of the tip 77 of the back support rod 76.

The inner shell 4 and the outer shell 3 forming the shell structure are made of, for example, a synthetic resin material having elasticity,
Each of them is integrally molded into a predetermined shape from polypropylene, polyethylene, polyvinyl chloride, polyamide, polyester or the like.

As is clear from FIG. 2, the inner shell 4 is formed so that its lateral shape is substantially L-shaped, and a fitting edge 6 projecting toward the outer shell 3 is formed on the outer periphery thereof.

The outer shell 3 is shaped so as to be fitted into the inner shell 4 from the rear side, and a predetermined space is formed in the inner shell 4 in the vicinity of the central portion as shown in the drawing, but the peripheral portion is fitted with the inner shell 4. It has a shape that fits in the edge 6. For this reason, the outer shell 3 has a shape curved toward the inner shell 4 near the outer peripheral portion thereof.

The outer peripheral portion of the inner shell 4 may be curved.

Further, in the shell structure portion above the upper end of the back support rod 76, the space between the inner shell 4 and the outer shell 3 is set small, and this portion is easily bent backward.

In such a shell structure, the outer shell 3 and the inner shell 4 which surround the seat of the internal structure are fixed by screws 83 or the like on the outer periphery thereof, while both shells on the backrest side are shown in FIG. Locking tools 20, 30, ...
., 60 are integrally assembled.

In the inner shell 4 that constitutes such a shell structure, the upper side of the portion corresponding to the backrest portion tilts rearward (in the vicinity of the upper end 77 of the back support rod 76 in FIG. 2) and the seat. A strip-shaped body 71 is provided that connects the portion corresponding to the rear portion of the portion.

The strip 71 will be described with reference to FIGS.

FIG. 3 is a partial front view of the shell structure forming the backrest viewed from the direction of arrow E in FIG. 2, and FIG. 4 is a partial perspective view of the strip 71 shown in FIG. 2, respectively. . Third to fourth
The belt-shaped body 71 shown in the figure is formed by using a part of the inner shell 4, and in a portion corresponding to the backrest portion of the inner shell 4, from the substantially central portion in the vertical direction of the backrest portion to the lower portion. It is formed by two slit-shaped opening portions 72 that are provided over the area.

The band-shaped body 71 is formed with a curved portion 75 that protrudes shallowly forward in a predetermined range in a downward direction from a connection portion between the band-shaped body 71 and the vicinity of the tilting base of the backrest.

Since the strip-shaped body 71 having such a curved portion 75 has elasticity in combination with the material forming the strip-shaped body 71, the tip end portion of the back support rod 76 located near the curved portion 75 shown in FIG. By bending the upper side of the shell structure corresponding to the backrest with respect to 77 as the fulcrum with respect to the lower side, the bending section 75 projects forward with respect to the lower side of the backrest.

Since the curved portion 75 projects forward with a connecting portion (hereinafter, also referred to as an upper connecting portion) between the belt-shaped body 71 and the vicinity of the tilting base portion of the backrest portion as a fulcrum as described later, the bending portion 75
The rigidity of the curved portion 75 is made larger than that of the other portions of the strip 71 by a means such as making the entire 75 thicker than the other portions of the strip 71, and the rib 78 is attached near the upper connecting portion. , And / or near the top connection is preferably reinforced by being particularly thicker than the rest of the strip.

Further, between the curved portion 75 of the belt-shaped body 71 and the connecting portion to the seat portion, a portion where the belt-shaped body is bent in a bellows shape in the longitudinal direction [hereinafter, bellows portion (79 in FIGS. 3 to 4). [Corresponding to] is provided], when the upper side of the backrest portion is tilted rearward with respect to the lower side, the bending portion 75 can easily project forward.

Further, it is convenient for manufacturing a chair that such a band 71 is integrally formed with the inner shell 4.

Next, the operation will be described.

As described above, in the chair of this embodiment, the entire backrest portion is uniformly tilted rearward, and the upper side of the backrest portion is further tiltable rearward with respect to the lower side. The curved portion of the strip 71 during the operation of the section.
75 projects forward.

Therefore, when the backrest point is located on the curved portion 75, the backrest point can be moved downward on the curved portion 75 as the upper side of the backrest portion tilts rearward with respect to the lower side. .

The forward projection of the curved portion 75 of the belt-like body 71 that enables the movement of the backrest point will be described.

When the backrest is leaned deeply, the load acts on the outer shell 4 in the extension direction and on the inner shell 3 in the compression direction.

For this reason, the deformation of the inner shell 4 and the outer shell 3 is clear from FIG. 2, and the inner shell 4 extends and compresses in the direction of arrow G in the figure, and the outer shell 4 in the direction of arrow H in the figure. To be done.

In response to such deformation of the inner shell 4, both sides of the band-shaped body 71 are separated from the inner shell 4 as shown in FIGS. 3 to 4, so that the curved portion 75 with the upper connecting portion of the band-shaped body 71 as a fulcrum. A force that tends to project forward is applied to the lower part of.

On the other hand, a force pulling the curved portion 75 downward acts from the connecting portion (lower connecting portion) between the strip 71 and the portion corresponding to the rear portion of the seat portion of the inner shell 4.

As a result of these forces being combined and a part of the lower portion of the bending portion 75 protruding forward, the shape of the bending portion 75 changes and the position of the backrest point moves downward on the bending portion 75.

Such movement of the backrest point will be described with reference to FIG.

5 (a) shows the case where only the upper side of the backrest portion 1 is tilted rearward, and FIG. 5 (b) shows the case where the entire backrest portion 1 is tilted backward.

In FIG. 5A, the backrest point X is located on the curved portion 75 of the strip 71 that connects the portion corresponding to the tilting base portion of the backrest portion of the inner shell 4 and the portion corresponding to the rear portion of the seat portion. At this time (in the standard state), the distance between the sitting position reference point Y and the backrest point X is A.

Next, the upper side of the portion corresponding to the backrest portion of the inner shell 4 is provided with the upper end portion of the back support rod 76 located near the curved portion 75.
Tilt backwards to the dotted line 4'with 77 as the fulcrum.

At this time, the bending portion 75 also projects forward to the dotted line, and the backrest point X moves downward to the position X '.

On the other hand, X ″ on the convex portion 75 indicated by the dotted line is the position when the backrest point X does not move downward.

In this way, the backrest point X is moved to the position under the curved portion 75, that is, the position X'by bending the upper portion of the backrest portion of the inner shell 4, and as a result, the distance between the seating reference point Y and the backrest point X '. B can be approximately equal to the distance A in the standard state.

Further, in FIG. 5 (b), the entire backrest portion of the inner shell 4 is tilted rearward to the position of the dotted line 4 '.

Also at this time, the bending portion 75 projects forward to the dotted line, and the backrest point X moves to the position X'below the bending portion 75.

On the other hand, when the backrest point X does not move like a conventional chair, the position of the backrest point is at the position X ″.

Even when the entire backrest is tilted rearward in this manner, the distance B between the seating reference point Y and the backrest point X'can be made substantially equal to the distance A in the standard state.

In the band-shaped body 71 that achieves such actions and effects, the curved portion 75
The bellows portion 79 located below the can adjust the amount of protrusion of the above-described curved portion 75 toward the front.

That is, when the backrest portion of the inner shell 4 is largely tilted rearward, the bellows portion 79 is also extended and the lower portion of the bending portion 75 is pulled with an appropriate force, so that the distance A and the distance B shown in FIG. Can be made as equal as possible.

In addition, the vicinity of the upper connecting portion of the strip 71, as described above,
Since it serves as a fulcrum that projects the curved portion 75 forward, it is preferably reinforced so as not to be deformed. As shown in FIG. 4, ribs 78 are provided and / or the rigidity of the curved portion 75 is increased by the belt-shaped body 71. It is preferable to make it larger than the other parts.

In the chair shown in FIG. 2, the back support rod 76 is provided inside the shell structure, but the back support rod 76 may be provided outside the shell structure, for example, outside the outer shell 3. Good.

Although the embodiment described above exemplifies the chair in which the back portion and the seat portion are substantially integrally formed by the shell structure, the present invention is also adopted in the conventional chair with a backrest shown in FIG. By providing the strip 71, it is possible to achieve the same effect.

Therefore, FIG. 7 shows another embodiment of the present invention.

The chair shown in FIG. 7 is similar to the chair shown in FIG. 6 except that the elastic strip 71 that connects the vicinity of the tilting base of the backrest (near the tip of the back support rod 84) and the rear of the seat is the upper connection. The curved portion 7 that protrudes shallowly forward in a predetermined range below the
5 and the bellows portion 79 is formed below the curved portion 75 and between the curved portion 75 and the lower connecting portion.

Even in such a chair, the distance between the seating reference point and the backrest point can be kept as constant as possible regardless of the tilting of the backrest.

This is because the curved portion 75 of the strip 71 projects forward as the backrest tilts, and the backrest point can move downward on the curved portion 75.

Although the chair of the present invention described so far has been described as having the pedestal 70, the chair can be applied to a chair that does not have the pedestal 70.

(Effect of the Invention) According to the chair of the present invention, the backrest point adjusted to the ideal position by the user in the chair in the standard state can be maintained even after tilting the backrest portion, and is worn by the user. You can also prevent tucking up your shirts.

[Brief description of drawings]

1 is a side view and a partial cross-sectional view of a chair according to the present invention, FIG. 2 is a cross-sectional view of the chair shown in FIG. 1, and FIG. 3 is a backrest viewed from the direction of arrow E in FIG. 4 is a partial front view of the shell structure, FIG. 4 is a partial perspective view of the strip 71 shown in FIG. 2, and FIG. 5 is an explanatory view for explaining the operation and effect of the present invention.
FIG. 6 is an explanatory view for explaining the position of a backrest point of a conventional chair, and FIG. 7 is a sectional view showing another example of the chair of the present invention. In the figure, X ... backrest support point, 71 ... strip, 75 ... strip 71
The curved part provided in the.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Michiyoshi Katagiri 137 Takano Stock Association, Miyata-mura, Kamiina-gun, Nagano In-house (72) Inventor Yoichi Suzuki, 6-1, 1-1, Oimari Minami, Higashinari-ku, Osaka, Osaka In the company

Claims (6)

[Claims] 1. A chair with a backrest in which an upper side of a backrest can be tilted rearward with respect to a lower side, and a belt-like chair having elasticity for connecting a rearward tilting base portion on the upper side of the backrest and a rear portion of a seat portion. A body is provided, and a portion extending downward from a connecting portion of the belt-shaped body to the backrest portion over a predetermined range is formed in a curved portion that protrudes shallowly forward, and the upper side of the backrest portion is with respect to the lower side. The chair with a backrest, wherein the curved portion projects forward with respect to the lower side of the backrest portion by tilting backward. 2. The chair with a backrest according to claim 1, wherein the rigidity of the curved portion is higher than that of the portion below the portion. 3. The front end of the back support rod is located in the vicinity of the curved portion of the belt-like body, and the upper side of the backrest tilts rearward with the front end of the back support rod as a fulcrum. Chair with backrest as described. 4. A belt-shaped body, wherein a portion near a connection portion to a backrest is thicker than other portions of the belt-shaped member and / or is reinforced by attaching ribs.
Alternatively, the chair with a backrest according to item 3. 5. The chair with a backrest according to claim 1, wherein the belt-shaped body between the curved portion and the seat portion is bent in a bellows shape in the longitudinal direction of the belt-shaped body. 6. The chair with a backrest according to any one of claims 1 to 5, wherein the belt-like body is formed integrally with the backrest portion.