JPH0870952A - Chair - Google Patents

Abstract

PURPOSE: To prevent a chair from deflective deformation generated in its seat shell centering on a recess formed in the shell when a load is applied to the seat from above by installing a back support rod mounting shaft on the side face of the recess in such an arrangement as alongside the side face. CONSTITUTION: A chair is structured so that a back support rod mounting shaft 412 is accommodated in tight contact in a recess 33 formed in a seat shell and that the left and right ends of the shaft are installed on the side face 33a of the recess 33 in such a positioning as laid alongside the side face simultaneously. Even though the seat shell 31 is going to make deflective deformation in such a direction that the side faces 33a of the recess 33 approach each other caused by a load F1 applied to the seat 3 from above, the seat shell 31 is prevented from deformation effectively by the given reaction force F2 owing to provision of the mounting shaft 412 between the side faces 33a. Thus the shaft 412 as an inevitable member to perform titling of the seat back serves also reinforcement of the seat shell 31, which eliminates necessity for provision of a reinforcing member which has been inevitable in any conventional arrangement, and also the number of part items and the man-hours in installation can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chair preferably used in offices and the like.

[0002]

2. Description of the Related Art Recently, most chairs used in offices and the like have a structure in which a backrest can be tilted.
In a chair with a conventional seat and back separated, the seat shell is supported by the seat support at the center of the lower surface, and the base end of the back support rod is horizontally placed on the seat support via the back support rod mounting shaft. The back shell is pivotally mounted so as to be rotatable around an axis, and the back shell is fixed to the upper portion of the back support rod at the center of the rear surface. In addition, the back shell is supported by the back support at the center of the rear surface, and the upper portion of the back support rod is pivotally attached to the back support via the back mounting shaft so as to be rotatable around a horizontal axis. Things are also being developed. The seat shell and the back shell are each made of resin and function as structural members for supporting loads.

[0003]

However, such a chair has a disadvantage that the seat shell or the back shell alone cannot sufficiently support the load.
Particularly, in order to improve the appearance of the mounting portion of the seat shell to the seat receiving portion, a concave portion is formed in the center of the lower surface of the seat shell, and the seat receiving portion is accommodated in this concave portion, A recess is formed in the center of the rear surface of the back shell in order to improve the appearance of the attachment part on the upper part of the back support rod, and the upper part of the back support rod is accommodated in this recess,
In the concave portion, the shell is easily deformed in a direction in which the side surfaces approach each other. Further, even in a chair in which an armrest is attached to the lower surface side portion of the seat shell, the load applied to the armrest becomes a major factor of the bending deformation of the seat shell in the same direction. For this reason, conventionally, as shown in FIG. 6, a steel reinforcing member H extending left and right is provided on the upper surface of the seat shell to reinforce the load on the seat shell, or A similar reinforcing member is also attached to the back shell for reinforcement. For this reason, there is a problem that the number of parts and the number of work processes are increased.

An object of the present invention is to effectively eliminate these problems including a review of the surroundings.

[0005]

In order to achieve the above object, the present invention employs the following configuration.

That is, according to the present invention, the seat shell is supported by the seat receiving portion via the recess formed in the center of the lower surface of the seat shell, and the base end portion of the back support rod is seated via the back support rod mounting shaft. In the chair pivotally attached about the horizontal axis, the left and right ends of the back support rod mounting shaft are attached to the side surfaces of the recess of the seat shell, and the back shell is centered on the rear surface. While being supported by the back support part through the recess formed in the part,
In a chair in which the upper part of the back support rod is pivotally attached to the back receiving portion via a back mounting shaft so as to be rotatable about a horizontal axis, the left and right ends of the back mounting shaft are attached to the side surfaces of the recess of the back shell. It is characterized by having been set.

[0007]

In the chair having such a structure, since both ends of the back support rod mounting shaft are attached to the side surfaces of the concave portion, even if a load is applied to the seat, the back support rods allow the side surfaces of the concave portion to approach each other. It is prohibited by the mounting shaft, and the bending deformation of the seat shell is effectively prevented. As described above, by providing the function of reinforcing the seat shell to the back support rod mounting shaft, which is an indispensable member for tilting the backrest, the reinforcing member can be eliminated. Also, since the left and right ends of the back support rod mounting shaft are attached to the side surfaces of the recess of the seat shell to prevent them from coming off, the back support rod mounting shaft may be simply a rod-shaped one. It is not necessary to use a special retaining structure between the back portion and the portion, and the back supporting rod attachment structure can be simplified.

On the other hand, even in the case of the back, even if a load is applied to the back from the front, the sides of the recesses are prevented from approaching each other by the back mounting shaft, and the bending deformation of the back shell is effectively prevented. . In this way, by providing the back mounting shaft with the function of reinforcing the back shell, a reinforcing member can be eliminated. Further, since both left and right ends of the spine mounting shaft are attached to the side surfaces of the recess of the spine shell so as to be prevented from coming off, the spine mounting structure including the spine mounting shaft and the peripheral portion can be simplified.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 1, the chair in this embodiment has a leg 1, a seat receiving portion 2, a seat 3, a back support rod 4, and a back 5.
Composed of and.

The leg 1 is adapted to support the seat receiving portion 2 on the upper end portion 11.

The seat receiving portion 2 has a downward U-shaped cross section,
It is pivotally attached to the upper end portion 11 of the leg 1 via a shaft hole 21 so as to be rotatable around a vertical axis, and the lower surface of the seat 3 is attached to and supported by the upper surface 2a. Also, a back support rod 4 is provided at the rear end 2b.
However, the back cover 22 is attached to each of the lower surfaces 2c.

The seat 3 is composed of a seat shell 31 made of resin and a seat cushion 32 attached to the upper surface 31a of the seat shell 31. A recess 33 as shown in FIGS. 2 and 3 is provided in the central portion of the lower surface 31b of the seat shell 31, and the seat receiving portion 2 is housed in the recess 33, and the seat receiving portion 2 is placed on the seat receiving portion 2. The seat shell 31 is fixed.

The back support rod 4 has a mounting hole 411 extending through the base end 41 in the horizontal direction, and a back shell 51 fixed to the upper end 42. The back support rod 4 is inserted into the mounting hole 411. It is pivotally attached to the rear end portion 2b of the seat receiving portion 2 via a mounting shaft 412 so as to be rotatable around a horizontal axis. The appearance of the back support rod 4 is adjusted by a back support cover 43. Further, a reaction force mechanism 44 by a spring is formed between the base end portion 41 and the seat receiving portion 2, and an elastic tilting operation is applied to the back 5 through the back support rod 4.

The back 5 is composed of a back shell 51 made of resin and a back cushion 52 attached to the front surface 51a of the back shell 51. A concave portion 53 as shown in FIGS. 4 and 5 is provided in the center of the rear surface 51b of the back shell 51, and the upper end portion 42 of the back support rod 4 is accommodated in the concave portion 53 and the upper end portion is accommodated. A back shell 51 is fixed to 42. Specifically, the back support rod 4 and the back 5 are connected via the back support portion 6. The back support portion 6 has a rearward U-shape in a flat cross section, and has a back mounting shaft 422 inserted horizontally through an upper end portion 42 of the back support rod 4 via a mounting hole 421.

In this embodiment, as shown in FIG. 2, the back support rod mounting shaft 412 is closely accommodated in the recess 33 of the seat shell 31, and the left and right ends of the shaft are attached to the recess 33 as shown in FIG. At the same time as the side surface 33a. Further, as shown in FIG. 4, the spine mounting shaft 422 is closely accommodated in the recess 53 of the spine shell 51, and both left and right ends thereof are arranged at positions to be attached to the side surface 53 a of the recess 53 at the same time.

With such a chair, as shown in FIG. 3, the recess 33 is formed by the load F1 applied to the seat 3 from above.
Even if the seat shell 31 bends and deforms in the direction in which the side surfaces 33a approach each other,
2, the reaction force F2 causes the seat shell 31 to move.
This effectively prevents the deformation. In this way, the back support rod mounting shaft 412, which is an essential member for tilting the backrest, also reinforces the seat shell 31, thereby eliminating the need for a conventionally required reinforcing member, and reducing the number of parts and mounting. The man-hour can be reduced. Also, the back support rod mounting shaft 4
The left and right ends of 12 are side surfaces 33a of the recess 33 of the seat shell 31.
, So that the back support rod mounting shaft 412 may be simply a rod-shaped one as shown in the drawing.
There is no need to provide a retaining structure composed of bolts and nuts between the back support rod mounting shaft 412 and the seat receiving portion 2, so that the number of parts and the number of mounting steps can be further reduced.

The same applies to the back, as shown in FIG.
Even if the back shell 51 tries to bend and deform in the direction in which the side surfaces 53a of the recess 53 approach each other due to the load F3 applied to the back 5 from the front, the back mounting shaft 422 is interposed between the side surfaces 53a, and the reaction force F4 causes the back mounting shaft 422 to move. The deformation of the shell 51 is effectively prevented. Thus, the back mounting shaft 4
By providing 22 with the function of the back shell 51, it is possible to eliminate the conventionally required reinforcing member and reduce the number of parts and the number of mounting steps. Further, the left and right ends of the spine mounting shaft 422 are provided on the side surfaces 53 of the recess 53 of the spine shell 51.
Since it is attached to a and is prevented from dropping, it is possible to further simplify the mounting structure of the back 5 in the peripheral portion including the back mounting shaft 422, and to reduce the number of mounting steps.

As described above, the chair of this embodiment has a particularly advantageous effect that the number of parts and the number of manufacturing steps can be reduced, and at the same time, the seat shell and the back shell can be reinforced. Becomes

It should be noted that the specific shape of each part is not limited to the above-described embodiment.
Various modifications are possible without departing from the present invention.

[0021]

As described in detail above, the chair of the present invention has the following features.
With respect to the load applied to the seat from above, the back support rod mounting shaft is attached to the side surface of the recess of the seat shell, whereby the flexural deformation caused in the seat shell around the recess can be effectively prevented. . In this way, by adding the function of reinforcing the seat shell to the back support rod mounting shaft, which is an indispensable member for tilting the backrest, no reinforcing member is required, and the number of parts and the number of mounting steps are reduced. be able to. In addition, since the left and right ends of the back support rod attachment shaft are attached to the side surfaces of the concave portion of the seat shell and are prevented from falling off, it is not necessary to take special measures to prevent the back support rod installation shaft from coming off. In addition, the number of mounting steps can be reduced at the same time.

Also, with respect to a load applied to the back from the front, the back mounting shaft supports the side surface of the recess of the back shell, thereby effectively preventing bending deformation caused by the back shell around the recess. Can be. As described above, by providing the back mounting shaft with the function of reinforcing the back shell, it is possible to eliminate the need for a reinforcing member and reduce the number of parts and the number of mounting steps. Also, since the left and right ends of the back mounting shaft are attached to the side surfaces of the concave portion of the back shell and are prevented from falling off, no special measures for preventing the back mounting shaft from being removed are necessary. Reduction will be achieved at the same time.

As described above, the present invention has a particularly beneficial effect of reducing the number of parts and the assembling process while favorably reinforcing the shell by simplifying the structure for reinforcing the load. .

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of the present invention.

FIG. 2 is a bottom view showing the connecting structure of the seat and the back support rod of the embodiment.

FIG. 3 is a sectional view showing a seat shell reinforcement structure of the embodiment.

FIG. 4 is a rear view showing the connecting structure of the back and the back support rod of the embodiment.

FIG. 5 is a sectional view showing a reinforcing structure of the back shell of the embodiment.

FIG. 6 is a perspective view showing a conventional seat shell reinforcement structure.

[Explanation of reference numerals] 2 ... Seat receiving portion 4 ... Back support rod 6 ... Back support portion 31 ... Seat shell 33 ... Recess 41 ... Back support rod base end 51 ... Back shell 53 ... Recess 33a ... Recess side 53a ... Recess Side 412 ... Back support rod mounting shaft 422 ... Back mounting shaft

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Fumihiro Kurata 5331 Nishiharu Near Shimogawara, Ina City, Nagano Takano Co., Ltd. Furniture Development Department

Claims (2)

[Claims] A seat shell is supported by a seat receiving portion via a concave portion formed in a center portion of a lower surface of the seat shell, and a base end portion of a back support rod is rotated about a horizontal axis around a seat support portion via a back support rod mounting shaft. A chair pivotally attached to the seat shell, wherein left and right ends of the back support rod mounting shaft are attached to side surfaces of the concave portion of the seat shell. 2. A back shell is supported by a back support through a recess formed in the center of the rear surface, and the upper part of the back support rod is rotatable about a horizontal axis by the back support via a back mounting shaft. A chair pivotally attached to the back shell, wherein left and right ends of the back mounting shaft are attached to side surfaces of the concave portion of the back shell.