JP2003135186A - Structure of chair seat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chair seat support structure which automatically prevents coming-off with the arrangement of a seat shell by forming a coming-off preventing member having a simple structure in the seat shell to prevent the seat shell from coming-off the rails of a seat receiving frame. SOLUTION: The rails 12 which are mutually in parallel, have an open top and extend in front and rear directions are arranged at the both left and right sides of the seat receiving frame 7. A downward projected lines 16 to be fitted to the rails 12 so as to be slidable in the front and rear directions are arranged at the both left and right sides of the lower surface of the seat shell 8 which is placed on the seat receiving frame 7. Elastically deformable coming-off preventing members 26 are integrally formed at the rear ends of the downward projected lines 16, which enters the inside of the rails 12 from a front part so as to be movable, which is projected outward from the downward projected lines 16 by protruding backward from the rear ends of the rails 12, and whose front surface sides face the rear ends of the rails 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for supporting a seat in a chair, and more particularly, a seat shell is slidable in the front-rear direction along a rail of a seat receiving frame, and the seat shell is a rail of the seat receiving frame. It relates to the structure of the seat of the chair that is prevented from coming out from the front.

[0002]

2. Description of the Related Art In a swivel chair or the like, a seat is provided on a seat frame made of metal fixed on a support base, a seat shell made of synthetic resin supported on both sides of the seat frame, and above the seat shell. There is a seat cushion body. Since the seat shell can be integrally formed, it is suitable for mass production and has excellent economical efficiency, and is widely used.

[0003]

In such a structure, it is preferable to make the seat shell slidable in the front-rear direction with respect to the seat receiving frame because it can be adapted to the sitting comfort of each seated individual. A retaining means must be provided to prevent the seat shell from falling off the seat receiving frame.
Conventionally, such retaining is performed by fitting a seat shell to a seat receiving frame and then attaching a stop member as a separate component with a screw or the like. This not only increases the number of parts, but also increases the number of assembly steps.

In view of the above problems, the present invention forms a retaining member for preventing the seat shell from coming off from the rail of the seat receiving frame on the seat shell with a simple structure, and has an action of preventing the removal. An object of the present invention is to provide a seat structure of a chair that is automatically performed when a seat shell is attached.

[0005]

According to the present invention, the above problems can be solved as follows. (1) Rails which are parallel to each other and extend in the front-rear direction and open upward are provided on both left and right sides of a seat receiving frame provided above a supporting base supported by legs and mounted on the seat receiving frame. On the left and right sides of the bottom surface of the seat shell to be placed, downward protrusions that slidably fit in the rail in the front-rear direction are provided, and the rear end portions of the downward protrusions are inserted into the rail from the front. An elastically deformable retaining member that is movable and protrudes rearward from the rear end of the rail so as to protrude outward from the downward protrusion and the rear end of the rail and the front surface side face each other is integrally provided.

(2) In the above item (1), the retaining member is composed of a pair of left and right protrusions which are spaced apart from each other in the left and right directions and elastically deformable in the respective directions.

(3) In the above item (2), the outer corners of both projecting pieces protruding outward from the downward projecting ridges are gradually converged toward the rear so as to approach the outer shape of the downward projecting ridges.

[0008]

1 is an exploded perspective view showing an essential part of a swivel chair with casters, which is equipped with an embodiment of the present invention, in the center of the upper surface of a leg (1) with casters. The support base (2) is rotatably mounted. The back frame (3) is pivotally supported at the rear part of the support base (2) so that the back frame can be tilted backward.
A back shell (4) and a back cushion body (5) are attached to the front surface, and a back outer panel (6) is attached to the back surface.

A seat frame is provided on the support base (2).
(7) is attached, the seat shell (8) is mounted on the seat receiving frame (7), and the seat cushion (9) is further attached.

The present invention relates to a seat support structure comprising the seat receiving frame (7) and the seat shell (8).

FIG. 2 is an enlarged perspective view of the seat receiving frame (7) viewed from above, FIG. 3 is an enlarged perspective view of the seat shell (8) viewed from below, and FIG. FIG. 7 is an enlarged vertical sectional front view of the right side portion in a state where the seat receiving frame (7) and the seat shell (8) are assembled.

As shown in FIGS. 1 and 2, a seat receiving frame
In (7), two steel pipes (10) extending in the left-right direction, which are hollowed out in the center, are arranged in parallel with a space in the front-rear direction, and in the middle of these steel pipes (10), It is formed by welding both ends of two connecting members (11) made of steel and having a U-shaped cross section that face in the front-rear direction.

At the left and right ends of the steel pipe (10), steel rails (1) extending in the front-rear direction forming grooves (12a) having a substantially V-shaped cross section are formed.
2) is welded. From these outer edges of the upper ends of the rails (12), which open upward, a short flange-shaped projecting piece (13) extending outward is extended. Further, an inward flange-shaped projecting piece (14) similar to the projecting piece (13) is extended from the inner edge of the upper end opened upward of the rail (12).

Further, a plurality of (four in the illustrated case) small projections (15) spaced apart from each other are provided at the front part of the bottom surface of the V-shaped groove (12a) so as to project upward. .

The seat shell (8) shown in FIG. 3 is an integrally molded product made of synthetic resin, and has a downward projecting ridge extending in the front-rear direction on the lower surface of the seat shell (8) at a position facing the groove (12a) on both left and right sides. (16) is projected. The downward projecting ridges (16) are fitted to the rails (12) of the seat receiving frame (7), and as shown in FIG. 4, the V-shaped grooves (12a) of the rails (12) are slanted on both left and right sides. It is of generally V-shaped cross section with two beveled portions (18) that at least partially engage the beveled surface (17).

On the outside of these downward protrusions (16),
A plurality of support pieces (20) horizontally projecting inward are integrally projectingly provided from the lower end portions of the left and right side edge portions (19) which extend downward at a slight distance from it. There is. When the seat shell (8) is attached to the seat receiving frame (7), these supporting pieces (20) are slidably engaged with the lower surface of the projecting piece (13) of the seat receiving frame (7) to form a seat. It prevents the shell (8) from coming off.

Left and right downward projections (1) on the seat shell (8)
A plurality of ribs (22) in the front-rear direction parallel to the downward protruding ridges (16) are formed near the inside of 6). Further, a rib (21) in the left-right direction is also formed orthogonal to the rib (22) in the front-rear direction. These ribs (21) and (22) are concentratedly distributed on the seated buttocks and the knees where load is applied.

Further, two downward projections (23) are integrally formed on the front portion of the seat shell (8) by interrupting the above-mentioned downward projecting ridges (16). The lower end of the lower protrusion (23) is
It extends slightly longer than the lower end of (16) and can engage with the small projection (15) of the seat receiving frame (7) shown in FIGS. 2, 4 and 5.

A lever (24) extending downward is integrally formed on the outer side of the lower protrusion (23). The lever (24) and the lower protrusion (23) are surrounded by a lever (24) facing inward in plan view. Since the U-shaped notch (25) is formed, by operating this lever (24), the portion inside the notch (25) is elastically bent outward and upward, and the lower protrusion (23) is lifted upward. be able to.

At the rear portion of the seat shell (8), a retaining member (26) is formed as a part of the downward protruding ridges (16) on both the left and right sides. As shown in FIGS. 3 and 6, in the rear portion of the seat shell (8), the downward protruding ridge (16) is interrupted by a certain length, and the retaining member (26) is interrupted at this interrupted portion. Are formed. The retaining member (26) is composed of a pair of left and right projecting pieces (26a) (26b) facing each other in the left-right direction with a space between them, and these left and right projecting pieces (26a) (26b) are provided at the rear end side. The outer surface shape is the same as the cross-sectional shape of the downward projecting ridge (16), and the outer surface shape on the front end side is such that the corners project more than the corners of the downward projecting ridges (16). That is, both protrusions (26
The outer corners of a) and (26b) gradually project downward toward the rear.
It is an inclined surface that converges so as to approach the outer shape of (16).

The two protruding pieces (26a) and (26b) are formed by integrally molding the seat shell (8). At this time, the both protruding pieces (26a)
A notch (27) is formed in the root part before and after (26b), and due to the presence of this notch (27), both the protruding pieces (2
6a) and (26b) are given elasticity so that they can be brought inward.

With the above-mentioned structure, the rear end (right side in the drawing) of the seat shell (8) shown in FIG. 3 is connected to the rail from the front of the seat receiving frame (7) shown in FIG. 2 (lower left side in the drawing). Groove of (12)
When the downward projection (16) is aligned with (12a) and fitted from the front, the upper surface of the support piece (20) of the seat shell (8) engages with the lower surface of the projection piece (13) of the rail (12). Further, the two slope portions (18) partially engage with both slopes (17) of the groove (12a) having a V-shaped cross section.

When the seat shell (8) is moved rearward in this state, the rear ends of the projecting pieces (26a), (26b) ride on the rail (12) and are gradually moved inward by the rail (12). In this way, the rail (12) elastically follows both the projecting pieces (26a) (26b), so that the downward projecting ridge (16) enters deep into the rail (12), and finally, shown in FIG. As described above, when the front ends of the two protruding pieces (26a) and (26b) deviate from the rear ends of the rails (12), the both protruding pieces (26a) and (26b) elastically return to the initial positions. In this state, both protrusions (26a) (26b)
Since the outer corner portion of the rail protrudes outward from the rail (12), the rail (12) cannot be moved in the opposite direction, which prevents the rail (12) from coming off.

[0024]

According to the invention of claim 1, the seat shell can be slid forward and backward along the rail of the seat receiving frame, and the seat shell can be pulled forward from the rail of the seat receiving frame. Can be prevented.

According to the second aspect of the present invention, the retaining mechanism can be formed integrally with the seat shell with a simple structure.

According to the third aspect of the present invention, the retaining function can be automatically performed when the seat shell is mounted.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a main part of a swivel chair equipped with casters according to an embodiment of the present invention.

FIG. 2 is an enlarged perspective view of a seat receiving frame as seen from above.

FIG. 3 is an enlarged perspective view of a seat shell seen from below.

FIG. 4 is an enlarged vertical sectional front view of a right side portion in a state where a seat receiving frame and a seat shell are assembled.

FIG. 5 is an enlarged vertical sectional side view of an engaging portion between a seat receiving frame and a seat shell.

FIG. 6 is an enlarged partial perspective view of a seat shell near a rear end on one side in a state where the seat shell is mounted on a seat receiving frame, as viewed from the lower rear side.

[Explanation of symbols]

(1) Legs with casters (2) Support base (3) Back frame (4) Back shell (5) Back cushion body (6) Back outer panel (7) Seat frame (8) Seat shell (9) Seat cushion body (10) Steel pipe (11) Connection member (12) Rail (12a) groove (13) (14) Projection piece (15) Small protrusion (16) Downward protrusion (17) Slope (18) Slope area (19) Side edge (20) Support piece (21) (22) Rib (23) Downward protrusion (24) Lever (25) Notch (26) retaining member (26a) (26b) Protrusion (27) Notch

Claims (3)

[Claims] 1. A rail extending parallel to each other and extending in the front-rear direction is provided on both left and right sides of a seat receiving frame provided above a support base supported by legs, and the rail is provided above the seat receiving frame. On the left and right sides of the lower surface of the seat shell to be mounted on the rail, downward protrusions that slidably fit in the rail in the front-rear direction are provided, and the rear end portion of the downward protrusion enters the rail from the front. Of the elastically deformable retaining member, which is movable and movable rearward, and which protrudes rearward from the rear end of the rail so as to protrude outward from the downward projecting ridge, and in which the rear end of the rail and the front surface side face each other. A support structure for a chair seat, which is characterized by being provided. 2. The retaining member is composed of a pair of left and right protrusions which are separated from each other in the left and right directions and elastically deformable in the respective directions.
Seat support structure in the described chair. 3. The chair seat according to claim 2, wherein the outer corners of both projecting pieces projecting outward from the downward projecting ridges are converged so as to gradually approach the outer shape of the downward projecting ridges toward the rear. Construction.