JP2002330843A - Elastic shell structure of chair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To exhibit enough elasticity and bending only by a shell structural material while securing enough strength as a backrest and a seat without an elastic body and a facing material. SOLUTION: A plastic-made shell structural material 4 used as a backrest 1 or a seat 6 of a chair is provided with a central part and an edge, whereby the elasticity and structural strength of the backrest 1 or the seat 6 is given by elastic deformation of the central part provided with a plurality of holes 7 and the elastic deformation of plastic of the peripheral edge of the central part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved chair back or seat. More specifically, the present invention relates to an improvement in a plastic molded article having a shell structure constituting a backrest or a seat (hereinafter referred to as a plastic shell structure material or simply a shell structure material).

[0002]

2. Description of the Related Art As shown in FIG. 3, a backrest 102 and a seat 103 of a chair 101 are generally provided with an elastic body (cushion) 105 such as urethane on a structural member 104 such as plywood, steel plate or resin. It is stretched and further covered with a skin material 106 such as cloth or leather to adjust its appearance. The elastic body 105 is effective for absorbing the shock at the time of sitting, giving appropriate elasticity to the back and buttocks of the human body, improving the sitting comfort, and reducing fatigue even when sitting for a long time.

On the other hand, there are many chairs 101 using a plastic molded product having a shell structure as a structural material of a backrest 102 or a seat 103. In this case, the plastic shell structural material is a structural member 104 of the backrest 102 or the seat 103.
In many cases, the bending of the resin itself is used to improve the fit.

[0004]

However, even though the plastic shell structure has elasticity, the elasticity is slightly increased as compared with a rigid body such as plywood.
Still another elastic member, that is, a urethane foam cushion or the like must be adhered thereon and further covered with a skin material. For this reason, the structure of the backrest and the seat is complicated, the number of parts is large, and the manufacturing process such as sewing and fastening requires time and increases costs. Also,
In recent years, the disposal of industrial waste has become a social problem, and it has been requested to reduce the amount of industrial waste by using recyclable structures and materials. It is preferable to use a structure that does not require a cushion material.

Accordingly, an object of the present invention is to provide an elastic shell structure which has sufficient elasticity and rigidity as a backrest or a seat of a chair by using only a plastic shell structure material.

[0006]

According to a first aspect of the present invention, there is provided an elastic shell structure of a chair, wherein a plastic shell structure used as a backrest or a seat of the chair is provided with a central portion and an edge. The elasticity of the back portion or the seat and the structural strength are provided by the elastic deformation of the central portion provided with the hole and the elastic deformation of the plastic around the central portion. According to this elastic shell structure, sufficient elasticity as a backrest or a seat, that is, elasticity equivalent to that of a cushion can be obtained by elastically deforming the central portion and the edge.

[0007] The elastic shell structure of the chair according to the second aspect,
A plastic shell structure used as a backrest or a seat of a chair is provided with a central portion and an edge, and a rib is formed in a central portion provided with a plurality of holes having different shapes. For example, if a large number of thin ribs are formed vertically and horizontally at the center and the two ribs are joined at the boundary, a hole is formed between the ribs. In this case, each hole has a structure surrounded by a rib.

According to a third aspect of the present invention, in the elastic shell structure of the first aspect, at least a part of the hole is formed in a shape different from other holes.

The invention according to claim 4 is the invention according to claim 1 or 2.
In the elastic shell structure of the chair described above, the hole is partially formed to be large or small.

According to a fifth aspect of the present invention, in the elastic shell structure of the chair according to any one of the first to fourth aspects, the holes are formed at different arrangement pitches.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be described below in detail based on an embodiment shown in the drawings.

FIG. 1 shows an example of a chair in which the elastic shell structure of the present invention is applied to a backrest. This chair has a frame 9
This is a pipe chair using steel pipes, and mainly comprises a backrest 1, a seat 2, and legs 3.

A shell structure material 4 constituting the backrest 1
Is a thin plate structure made of an integrally molded product of plastic, and has a mesh portion 8 formed by a large number of small holes 7,. Here, the mesh portion 8 is intentionally formed to protrude forward (to the seating side) in a dome shape, and is provided so as to obtain elasticity suitable for the shell structure member 4 to be used as a backrest. . The elasticity of the mesh part 8 depends on the material of the shell structural material 4,
Thickness, size, number, spacing of small holes 7 and mesh portion 8
The size can be freely set depending on the height of the protrusion. Since the plastic shell structure 4 utilizes the elasticity of the plastic itself, it is preferable to make the plastic shell structure 4 as thin as possible as long as the strength of the backrest can be maintained.

The mesh portion 8 is formed by injection-molding a shell material 4 of a predetermined shape including a dome-shaped projecting portion having a desired projecting amount, and then punching a number of small holes 7,. A dome-shaped protrusion and a small hole 7 having a predetermined protrusion amount are formed by punching the protrusion and its periphery by machining or punching, or at the time of injection molding of the shell structure material 4.
.., 7 are simultaneously formed by the mold. The projection of the mesh portion 8 of the shell structure member 4 in a specific direction is generally given by molding using an injection molding die, a press die, or the like. However, small holes 7,... Due to the difference in shrinkage at the time or the difference in cross-sectional shape, the shape may be changed to a dome shape with shrinkage after molding.

The dome shape may be, for example, made to protrude equally over the entire surface of the backrest or the seat portion. However, the dome shape may be made to partially protrude or partially protrude more than other portions. Is also good. Particularly preferably, when the shell structure member 4 is attached to the frame 9 and used as a backrest, the projection amount of the portion where the waist corresponding to the back fulcrum hits is maximized,
That is, the protrusion amount is formed so as to gradually decrease as the distance therefrom increases. For example, it is provided so as to have the maximum amount of protrusion at a portion located about 150 mm above the seating surface. As long as the rigidity of the backrest or the seat can be ensured, the mesh portion 8 may occupy most of the portion except for the edge of the shell structure material 4.

The mesh portion 8 has a large number of small holes 7,
, 7 as well as a mesh formed with a large number of thin ribs vertically and horizontally. In this case, for example, if the vertical ribs and the horizontal ribs are formed so as to be shifted back and forth, and the two ribs are joined at a boundary portion between them, it can be manufactured by injection molding. The shell structural member 4 has, for example, a horizontally-long rectangular shape, and is covered on the pipe frame so that both sides and a part of the upper part are supported by the back support rod 5 constituted by a part of the pipe frame. It is fixed with screws 10. A substantially semi-cylindrical pipe cover portion 11 is integrally formed on both sides and an upper edge of the shell structure member 4. Sticking is achieved.

On the other hand, the plastic shell structural member 4 is preferably formed so as to be curved backward as a whole in order to fit the back. In this case, the contact surface with the back while sitting is increased, and the back fatigue when leaning for a long time can be reduced.

According to the backrest 1 constituted by the plastic shell structure member 4 constituted as described above,
The mesh portion 8 which is intentionally protruded forward so as to have a softness that gives a comfortable feel to the back when leaning on the back is structurally elastic and can be deformed by an appropriate load.
The portion around the mesh portion 8 also has elasticity due to the bending of the thin plastic itself. Therefore, in the shell structural member 4, the mesh portion 8 can be given an appropriate elasticity. As a result, the entire backrest 1 can be given an appropriate flexure, and can be sufficiently used as a backrest of a chair. be able to. In other words, the shell structure member 4 made of plastic can sufficiently serve as a backrest without using a conventional elastic body or skin material. Further, the shell structure material 4 having the mesh portion 8 has good air permeability, so that even if the shell structure member 4 leans on the backrest 4 for a long time, there is little unevenness.

As described above, the use of the elastic shell structure material 4 for the backrest of the chair allows the backrest to be deformed and bent when seated or leaned on. Since a pipe is used, if the deflection of the pipe is incorporated in the calculation in advance, it is possible to obtain a chair having more moderate elasticity as a whole.

The above embodiment is one preferred embodiment of the present invention, but the present invention is not limited to this embodiment, and various modifications can be made without departing from the gist of the present invention. For example, in the present embodiment, the shape of the small holes 7,..., 7 is substantially round, but is not particularly limited thereto, and may be a hexagon, another polygon, or a square. Similarly, the size and number of the small holes 7,..., The arrangement pitch, and the like are not limited at all, and are appropriately selected so that the desired properties of the plastic shell structure material 4 can be obtained. The arrangement pitch of the small holes 7 is fixed in the present embodiment, but is not particularly limited to this. The arrangement may be such that only a part of the small holes 7 is concentrated to form a coarse-dense distribution so as to obtain an uneven elasticity. . Also, a desired elasticity may be obtained by partially increasing or decreasing the size of the small holes 7 without making them uniform.

In the present embodiment, an example in which the shell structural member 4 is mainly applied to the backrest has been described. However, the present invention is not particularly limited to this and can be applied to the seat 6.
In this case, the seat 6 is supported by the left and right pipe frames 9, 9.
The seat 6 may be supported by the side. Since a large load is applied to the seat 6 over a wider area than the backrest, it is preferable that the seat 6 be wider and have higher rigidity than the mesh portion 8 of the backrest.

Further, in this embodiment, the shell structure material 4
Is a rectangular shape that is long horizontally, but the shape is not particularly limited, and may be long vertically. In addition, shell structural material 4
The upper part can be slightly bent back so that it can fit more on your back when leaning. (Example) The mesh portion 8 was formed into the shape shown in FIG. For example, the maximum protruding portion of the mesh portion 8 is set about 150 mm above the seat 6, so that the shape is adapted to the waist portion so that comfort can be given at the time of sitting. The mesh portion 8 is provided with a small hole 7,...
It is composed of 0 rows, 40 rows horizontally, and a total of about 800 arranged at a constant pitch. The entire size of the mesh portion 8 is about 20 cm in length and 40 cm in width. Further, the mesh portion 8 is deliberately curved so as to protrude forward and has a dome shape. According to the shell structure material 4 formed as described above, the back can be constituted by a simple structure directly attached to the frame 9 as shown in FIG.
In particular, elasticity that gives a comfortable feeling to the back fulcrum is given.

[0023]

As described above, the elastic shell structure of the chair according to the present invention provides a plastic shell structure material used as a backrest or a seat of a chair with a central portion and an edge, and a central portion provided with a plurality of holes. The elasticity of the back part and the elasticity of the plastic around the central part and the elasticity of the plastic around the central part provide the elasticity and structural strength of the backrest or seat. Elasticity, that is, elasticity comparable to that of the cushion is obtained. In other words, it is possible to have both the elasticity and structural strength required for a backrest or a seat of a chair, and it is possible to form a backrest or a seat with this shell structural material alone, and to put a skin material on the backrest. And seats can be configured.

Accordingly, the number of parts constituting the backrest and the seat of the chair can be greatly reduced, and operations such as sewing and fastening are not required, so that production costs can be reduced. Further, the structure of the backrest and the seat can be simplified, and at the same time, the weight of the entire chair can be reduced.

According to the elastic shell structure of the chair according to the second aspect, the plastic shell structure used as the backrest or the seat of the chair is provided with a central portion and an edge, and a central portion provided with a plurality of holes having different shapes. Since the ribs are formed, the central portion and the edge are elastically deformed, so that a sufficient elasticity as a backrest or a seat, that is, elasticity equivalent to that of the cushion can be obtained.

According to the elastic shell structure of the chair according to the third aspect, at least a part of the hole is formed in a shape different from other holes, so that the plastic shell structural material can obtain desired properties. .

According to the elastic shell structure of the chair according to the fourth aspect, since the hole is formed partially large or small, desired elasticity can be obtained.

According to the elastic shell structure of the chair, since the holes are formed at different arrangement pitches, the desired properties can be obtained from the plastic shell structure material.

[Brief description of the drawings]

FIG. 1A is a side view of a chair showing an example of an embodiment of the present invention, and FIG. 1B is a plan view showing a cross section taken along line II.

FIG. 2A is a cross-sectional side view taken along line II-II of the shell structural material, and FIG. 2B is a perspective view of the shell structural material.

FIG. 3 is a perspective view showing a conventional chair.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Backrest 4 Plastic shell structure material 6 Seat 7 Hole 8 Mesh part (central part)

Claims (5)

[Claims] 1. A plastic shell structure used as a backrest or a seat of a chair is provided with a central portion and an edge, and a plurality of holes are provided to elastically deform the central portion and a plastic at the edge around the central portion. An elastic shell structure of a chair, characterized in that the elastic deformation of the backrest or seat imparts elasticity and structural strength. 2. A chair characterized in that a center portion and an edge are provided in a plastic shell structure material used as a backrest or a seat of the chair, and a rib is formed in the center portion provided with a plurality of holes having different shapes. Elastic shell structure. 3. The elastic shell structure of a chair according to claim 1, wherein at least a part of the hole is formed in a shape different from other holes. 4. The elastic shell structure for a chair according to claim 1, wherein the hole is formed to be partially larger or smaller. 5. The elastic shell structure of a chair according to claim 1, wherein the holes are formed at different arrangement pitches.