JPH10179325A - Device for attaching back plate of chair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a distance between the position of contact of a back plate with a back support and the position of a device for fixing them. SOLUTION: This device is such that the lower end 32 of a recess of a back plate 18 is brought into contact with the stepped part 8 of a back support 2. In addition, a lug 24 provided in the back plate 18 near the contact position is engaged with an engaging groove 12 provided in the back support 2. Since a distance is short between the position of the contact and that of the fixing device, this distance can be set precisely, thereby enabling the lug 24 to be surely engaged with the engaging groove 12 in a state where the back plate 18 is in contact with the back support 2, and also eliminating a space between the lug 24 and the engaging groove 12 in the same state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for attaching a backrest of a chair to a backrest standing upright from both rear sides of a seat of the chair.

[0002]

2. Description of the Related Art Conventionally, a backrest plate of a chair is attached to a backrest rod standing upright from both rear sides of a seat plate of the chair, as shown in FIG. 9 (Japanese Utility Model Publication No. 41-16557). The backrest rod (62) penetrates into the recess (61), the upper end of the backrest rod (62) abuts on the back end (upper end) of the recess and is positioned, and the recess (61) and the backrest rod (62). 62) are fixed using predetermined fixing means. In FIG. 9, the fixing means is formed by forming a through-hole (63) in the recess (61) and projecting the backrest rod.
(64), and the projection (64) is engaged with the through hole (63) to fix the recess (61) and the backrest rod (62). Various fixing means are conceivable. In some cases, a through hole is formed in the concave portion and the backrest bar, and the fixing member is fixed by a rivet.

[0003]

However, the backrest rod (6
Since the distance between the upper end of 2) and the projection (64) is usually large, it is difficult to provide the projection (64) by accurately setting this distance,
In addition, since the distance between the deep end (upper end) of the recess and the through hole (63) is usually large, it is difficult to provide the through hole (63) with this distance accurately.

Therefore, the upper end of the backrest rod (62) may not come into contact with the rear end (upper end) of the recess when the projection (64) and the through hole (63) are engaged. In such a case, a force in the direction of pushing down the backrest in the axial direction is applied to the backrest rod (61) (this force is applied when the standing person grips the upper end of the backrest with his hand, When this backrest tries to support the whole weight through this hand), this force will be supported only between the projection (64) and the through-hole (63), and the projection (64) And an excessive force is generated between
This part may be broken. The same applies to a case in which a through hole is formed in the recess and the backrest bar as a fixing means, and the hole is fixed by a rivet.

[0005] Even when the upper end of the backrest rod (62) is in contact with the deeper end (upper end) of the recess, the projection (64) may not be able to coincide with the through hole (63). At this time,
The engagement work between the projection (64) and the through hole (63) cannot be performed immediately. The same applies to a case in which a through hole is formed in the recess and the backrest bar as a fixing means, and the hole is fixed by a rivet.

The through-hole (63) can be a long hole (in FIG. 9, it is a long hole).
Since the projection moves within (63), an integral fixation between the backrest rod (62) and the recess (61) cannot be obtained.

An object of the present invention is to solve the above problems,
It is an object of the present invention to provide a device for mounting a back plate of a chair.

[0008]

In order to achieve the above object, the present invention provides a backrest mounting device for a chair according to the present invention. In addition to providing a step portion having a reduced upper cross-sectional shape, an engaging groove is formed in the vicinity of the step portion in the axial direction, and the upper portions of the left and right backrest bars are provided on the lower left and right sides of the backrest plate. A recess for fitting and a step portion contacting the lower end is provided, and a recess is provided below the recess to engage with the engaging groove of the backrest rod, and to vertically attach the backrest plate to the backrest rod. And a locking claw elastically biased in the direction of the engagement groove.

Preferably, the locking claw is attached to the backrest plate by a screw.

[0010]

In FIG. 2 and FIG. 3, a pair of left and right backrest rods (2) are integrally formed by a mold, and a lower member (5) made of aluminum is attached to an upper member made of steel or stainless steel pipe. The member (6) is inserted, and the upper member (6) is exposed above the intermediate portion. Therefore, a step (8) is formed in this portion.

The lower member (5) made of aluminum has a stepped portion.
In (8), a predetermined amount of a hump (10) is left, and an engagement groove (12) is recessed in the axial direction below this portion.

An axial cutout is formed at the upper end of the upper member (6).
(14) is formed. Lower member made of aluminum (5)
At the lower end, an attachment portion (16) for attachment to a chair frame is formed.

Next, as shown in FIGS. 4 and 5, upper members (6) of left and right backrest rods (2) are fitted to lower left and right sides of a backrest plate (18), and a step (8). Where the bottom contacts the bottom
(20) is provided.

[0014] The length of the recess (20) is determined by the upper member (6) that faces out.
Is longer than the length of the part. Also, as shown in FIGS. 5, 6, and 7, the inner wall of the recess (20) has a spline (2).
3) is formed. The inner diameter of the spline (23) is slightly smaller than the diameter of the upper member (6).

Below the recess (20), there is formed a bag (21) for shielding a stepped knob (10) and a later-described locking claw from the outside.

The back plate (18) is integrally formed at a low cost by injecting a resin into a mold, and has a loop-shaped rearward protruding ridge (22) formed at the periphery thereof. The recess (20) is formed in the ridge (22). Therefore, the ridge (22) has a larger diameter at the portion where the recess (20) is formed. The portion of the ridge (22) above the recess (20) also has a large diameter, and a hollow portion is formed inside this portion (not shown).

As shown in FIGS. 6 and 7, a locking claw (24) which engages with the engaging groove (12) of the backrest rod is provided below the recess (20).
Is provided. The locking claw (24) is hook-shaped downward and has a tapered portion (26) for facilitating penetration of the upper member (6). In addition, since the locking claw (24) is formed of an elastic material and has a predetermined vertical length,
It is elastically biased in the axial direction. At the mounting end of the locking claw (24), a mounting hole (28) is formed, and the mounting hole (28)
Is exposed downward, a screwdriver is inserted from below, and the mounting hole (28) is fixed to the upper end of the bag (21) with the screw (30).

Next, the operation will be described. A predetermined cushion material and a skin material are placed on the surface of a back plate (18) integrally formed by injection molding of a mold. In addition, the locking claw (24) is mounted in the bag portion (21) with the screw (30). On the other hand, the mounting portion (16) of the pair of backrest rods (2) is mounted on the frame of the chair. Then, a pair of backrest rods (2) and a backrest plate (18)
Align the position of the pair of recesses (20) and push in as it is. Since the inner diameter of the spline (23) is slightly smaller than the diameter of the upper member (6), the spline (23) is pushed in while being slightly expanded. Since the notch (14) is formed at the tip of the pipe, the lower end penetration of the recess (20) can be easily fitted to the upper member (6). Taper of locking claw (24)
Since (26) is along the outer surface of the upper member (6), the locking claw (24) is elastically bent to the opposite side to the upper member (6).

Then, as shown in FIG. 1, the step (8) comes into contact with the lower end (32) of the recess (20). Further, the engaging claw (24) is fitted in the fitting groove (12), and the state of elastic bending is eliminated. This completes the attachment of the back plate (18) to the back rod (2) (FIG. 8). In the attached state, the upper end (34) of the aluminum lower member (5) is housed in the bag (21) (FIG. 1).

Since the fitting groove (12) is located near the lower end (32) of the recess (20) and the length of the locking claw (24) is short, it is necessary to accurately measure the distance therebetween. Can be. Therefore, the locking claw (24)
Does not fit into the fitting groove (12), and in the fitted state, there is no empty space between the locking claw (24) and the fitting groove (12).

Since it can be attached only by pushing in, it can be attached very easily and quickly. Since the mounting device, including the upper end (34) of the aluminum lower member (5), is contained in the bag (21),
That is, the portion of the mounting device is not visible from the outside, and a good chair design is obtained (FIG. 8). Backrest (18) and backrest rod
Since there is no play between (2) and the above, it is possible to obtain a favorable feeling of the user.

Even if a force is applied to the backrest in the direction of pushing down the backrest rod in the axial direction, the backrest plate (18) and the backrest rod (2) are in direct contact with each other. it can.

Since the backrest rod (2) is in contact with the lower end of the recess, the backrest plate (18) above the contact position has a resin (the resin forming the recess) corresponding to the length of the recess. Therefore, the resin corresponding to the length of the recess comes into contact with the backrest rod (2), and the resin can sufficiently withstand the force even when the force in the direction of pushing down acts. .

Next, in order to remove the backrest plate (18) from the backrest rod (2), two flat-blade screwdrivers are used to lock the claw (24) and the hump (10) in both the bag portions (21). And the locking claw (24) is separated from the fitting groove (12), and in this state,
Raise the back plate (18). Or using a driver,
The screw (30) in the bag (21) may be removed, the locking claw (24) may be removed, and the back plate (18) may be pulled up. In this way, the back plate (18) and the back rod (2) can be easily separated, and the back plate (18) made of resin alone can be effectively recycled.

To fit the back plate (18) onto the back rod (2) again, push the back plate (18) into the back rod (2) in the same manner as described above. Locking claw (24)
If has been removed, re-attach the locking claw (24) using the screw (30) and then push it in.) As above,
If the backrest plate (18) is removed from the backrest rod (2), the locking claws (24), screws (30), etc. will be damaged, which is undesirable in terms of design. Department (21)
Since it is shielded inside, a good design is maintained.

[0026]

According to the present invention, a step portion is provided in the middle portion of the backrest rod, and an engaging groove is provided in the vicinity of the step portion. Therefore, the distance between the contact portion between the backrest rod and the backrest plate and the engagement portion between the engagement groove and the locking claw is short, and the distance can be accurately determined.

By attaching the locking claw to the backrest plate with a screw, when the backrest plate is integrally formed of resin, a mold having no locking claw may be manufactured. The shape can be made simple and easy to make.

[0028]

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a state in which a backrest plate is attached to a backrest rod using the backrest attachment device for a chair of the present invention.

FIG. 2 is a side view of the right-side backrest rod viewed from the front of the chair viewed from the left side in the apparatus for mounting a backrest plate of a chair according to the present invention.

FIG. 3 is a partial sectional front view of FIG. 2;

FIG. 4 is a rear view of the back plate of the apparatus for mounting a back plate of a chair according to the present invention.

FIG. 5 is a bottom view of FIG. 4;

FIG. 6 is an enlarged detail view of the recess of FIG. 5;

FIG. 7 is an enlarged cross-sectional detail view of the recess of FIG. 4;

FIG. 8 is a side view of a chair to which the backrest mounting device of the present invention is applied.

FIG. 9 is a perspective view showing a conventional back plate attaching apparatus.

[Description of Signs] (2) Backrest rod (5) Lower member of backrest rod (6) Upper member of backrest rod (8) Step (10) Hump (12) Engagement groove (14) Notch (16) Mounting part (18) Back plate (20) Concave part (21) Bag part (22) Convex ridge (23) Spline (24) Locking claw (26) Taper part (28) Mounting hole (30) Screw (32) Concave (20) lower end (34) upper end

Claims (2)

[Claims] 1. A step having an upper cross-sectional shape smaller than a lower cross-sectional shape is provided at an intermediate portion of a backrest rod standing upright from both rear sides of a seat plate, and an engaging groove is provided near the step. The upper part of the left and right backrest rods is fitted in each of the left and right lower parts of the backrest plate, and the step part is provided with a recess in which the step abuts on the lower end thereof. Downward, engaging with the engaging groove of the backrest rod,
A mounting device for a backrest plate of a chair, characterized in that a locking claw elastically biased in the direction of the engaging groove is provided for mounting the backrest plate on the backrest rod so as to be vertically movable. 2. The backrest attaching device for a chair according to claim 1, wherein the locking claw is attached to the backrest by a screw.