JPH0928506A - Mounting device for chair backrest plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide enough strength to prevent the breakage of a chair backrest plate and a backrest bar, even when the vertical size of the plate is large and the plate is substantially inclined back, allowing the nut of the plate to be easily aligned with a mounting hole on the upper part of the bar for fastening the plate and the bar to each other in a short time. SOLUTION: A vertically extending projection part 6 is formed on the rear side of a backrest plate 5. On the other hand, a vertically extending groove part 9 to be coupled to the projection part 6 for the concealment thereof from the rear side is formed on a backrest bar 4. The projection part 6 and the groove part 9 are, then, coupled to each other and secured with screws.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for attaching a backrest plate to a back rod which rises rearward and upward from a lower portion of a seat of a chair.

[0002]

2. Description of the Related Art Conventionally, in order to attach a backrest plate to the upper part of a back rod that stands rearward and upward from a seat lower portion of a chair, nuts are embedded in a plurality of places on the backrest plate, and the backrest is opposed to these nuts. After making a mounting hole on the upper part of the rod and aligning the position of each nut with the mounting hole and abutting the back rod against the backrest plate, insert a setscrew from the back side of the back rod into the mounting hole to attach it to the nut. They were screwed together and fastened to the backrest plate and the back rod.

[0003]

According to the above-mentioned conventional means, a chair having a small backrest plate can have a sufficient strength, but the vertical dimension of the backrest plate is large and the backrest plate is inclined by the tilting device. In a case where the backrest plate and the back rod are largely tilted, a large load is applied to the backrest plate and the back rod, so that the backrest plate and the back rod may be damaged. Also, the nuts of the backrest plate and the mounting holes in the upper part of the back rod are complicated to align, and it took time to attach the backrest plate and the back rod.

The present invention has been made in view of the above-mentioned problems, and even when the backrest plate has a large vertical dimension and the backrest plate is largely tilted backward by the tilting device, the backrest plate and the backrest are not provided. It has sufficient strength to prevent the rod from being damaged, and the nuts on the backrest plate and the mounting holes on the upper part of the back rod can be easily aligned to fasten the backrest plate and the back rod in a short time. It is an object of the present invention to provide a backrest plate attachment device for a chair that can be performed.

[0005]

According to the present invention, the above-mentioned problem is solved as follows. (1) A backrest plate having a backrest cushion body attached to the front surface, and a back rod fixed to the back surface of the backrest plate so as to support the backrest plate, and a vertical direction on the back side of the backrest plate. A projection extending to the back rod, and a groove extending in the up-down direction that is fitted to the projection on the back rod and covers the projection from the back surface, and the projection is engaged with the groove to stop the projection. I tried to wear it.

(2) In the above item (1), a pair of left and right convex portions extending in the vertical direction is provided on the back side of the backrest plate, and the back rod covers each of the convex portions from the back side. A pair of left and right groove portions extending in the up-and-down direction are provided, and the both convex portions and the both groove portions are engaged and fixed.

(3) In the above item (1) or (2), the back surface of the convex portion of the backrest plate and the bottom surface of the groove portion of the back rod facing the back surface are brought into contact with each other, and the back surface of the groove portion is stopped. The backrest plate is fixed to the back rod by screws.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION A chair (1) shown in FIG. 3 is a backrest chair having a cushion body (2) in which a seat portion and a backrest portion are integrally connected. Inside the backrest (3) of the chair (1), a back rod (4) stands up from the bottom of the seat to the upper rear. This back rod (4) is well shown on the right side of FIG.
The pivot (4a) at the lower end of the back rod (4) forms a part of the tilting device of the backrest (3).

A backrest plate (5) is attached to the front of the back rod (4). The above-mentioned cushion body (2) is attached to the front surface of the backrest plate (5). This backrest plate (5) is well shown on the left side of FIG.

As is apparent from FIG. 1, on the back surface of the backrest plate (5), two vertically extending projections (6) are formed in parallel with each other. Since the backrest plate (5) is formed by molding a hard elastic material such as a synthetic resin material, the convex portion (6) has other engaging holes (7) and reinforcing ribs.
(8) and the like are integrally formed. A screw hole (6a) is formed on the back surface of the convex portion (6).

On the other hand, on the front surface of the back rod (4), two groove portions (9) extending in the vertical direction are formed in parallel with each other on both sides thereof. These grooves (9) have a width and a depth sufficient to fit the protrusions (6) of the backrest plate (5).

Therefore, in the state where the groove portion (9) is fitted to the convex portion (6), the central portion (10) formed between the two groove portions (9) (9) of the back rod (4) is It comes in contact with the back surface of the backrest plate (5). This abutting relationship is best shown in the cross-sectional view of FIG.

In this state, the convex portion of the backrest plate (5) described above
The screw hole (6a) of (6) and the screw hole (9a) formed in the groove (9) of the back rod (4) are matched, and the backrest plate (5) is fixed by the screw (11) (see FIG. 2). ) Is fixed to the back rod (4). At this time, back plate (5)
The rear surface of the convex portion (6) is in contact with the bottom surface of the groove portion (9) of the back rod (4).

[0014]

According to the present invention, a convex portion extending in the vertical direction is provided on the back side of the backrest plate, and a groove extending in the vertical direction is fitted on the back rod to cover the convex portion from the rear surface. Since the convex portion and the groove portion are engaged with each other to be fixedly attached, both the backrest plate and the back rod are improved in strength against backward bending and twisting, and the backrest plate is formed. Even if the backrest plate has a large vertical dimension and the backrest plate is largely tilted backward by the tilting device, it is possible to obtain the one having sufficient strength so as not to damage the backrest plate and the back rod.

Further, by fitting the groove of the back rod to the convex portion of the backrest plate, the mounting positions of the backrest plate and the upper part of the backrest can be easily aligned, and the backrest plate and the back rod can be stopped. You can wear it in a short time.

According to a second aspect of the present invention, a pair of left and right convex portions extending in the vertical direction are provided on the back side of the backrest plate, and the back rod covers each of the convex portions from the back side. By providing a pair of left and right groove portions extending in the vertical direction and engaging and fixing the both convex portions and the both groove portions, it is possible to further improve the strength against backward bending and twisting. it can.

According to the third aspect of the present invention, the back surface of the convex portion of the backrest plate is brought into contact with the bottom surface of the groove portion of the back rod facing the back surface, and the backrest is supported by a set screw from the back surface of the groove portion. When the plate is fastened to the back rod, the groove of the back rod firmly holds the convex part of the backrest plate, so there is little chance that the nut and set screw will be twisted directly, and the effect that the looseness between them does not easily occur Can play.

[Brief description of drawings]

FIG. 1 is a perspective view showing a back side of a backrest plate and a front side of a back rod to which the present invention is applied, in a state where the back side is opened to the left and right.

FIG. 2 is a transverse cross-sectional view showing a state in which a backrest plate and a back rod are connected, and an enlarged cross-sectional view taken along line II-II of FIG.

FIG. 3 is a side view showing a backrest chair, to which the present invention is applied, with a part thereof broken away.

[Explanation of symbols]

 (1) Backrest chair (2) Cushion body (3) Backrest (4) Backrest (4a) Axis (5) Backrest plate (6) Convex portion (6a) Screw hole (7) Engagement hole (8) Reinforcing ribs (9) Groove (9a) Mounting hole (10) Center part (11) Screw

Claims (3)

[Claims] 1. A backrest plate having a backrest cushion body mounted on a front surface thereof, and a back rod fixed to a back surface of the backrest plate, the protrusion extending in a vertical direction on a back side of the backrest plate. And a groove extending in the up-down direction is formed on the back rod so as to be fitted to the projection and cover the projection from the back surface so that the projection and the groove are engaged and fastened. A backrest plate mounting device for a chair, which is characterized in that 2. A pair of left and right convex portions extending in the vertical direction is provided on the back side of the backrest plate, and a back rod includes a pair of left and right extending vertically covering the convex portions. 2. The backrest plate attachment device for a chair according to claim 1, wherein a groove portion is provided, and the both convex portions and the both groove portions are engaged with each other and fixed. 3. The back surface of the convex portion of the backrest plate and the bottom surface of the groove portion of the back rod facing the back surface are brought into contact with each other, and the backrest plate is fixed to the back rod by a set screw from the back surface of the groove portion. The backrest plate attachment device for a chair according to claim 1 or 2, which is worn.