JP4889946B2 - Chair backrest structure - Google Patents

Description

  The present invention relates to a backrest structure of a chair, and more particularly to a mounting structure for a backboard of a backrest.

In a conventional chair, both end portions of a seat substrate made of a synthetic resin, in which a seat and a backrest are integrated, are fitted into recessed grooves formed on opposing surfaces of a pair of left and right side frames. In addition, there is one in which a rear upper end, a front end, and an intermediate portion of a seat substrate are supported by a connecting rod that is laid between opposing surfaces of both side frame bodies (see, for example, Patent Document 1).
Japanese Utility Model Publication No. 54-21210

In the chair described in Patent Document 1, the rear upper end and the front end of the seat substrate are bent in the same direction, that is, in a downward arc shape.
Such a structure is generally applied to a chair in which a seat plate and a back plate are separated. That is, the front and rear ends of the seat plate are bent in a downward arc shape, and the upper and lower ends of the back plate are bent in a backward arc shape.

However, when the upper and lower ends of the back plate are bent in a backward arc shape, the bent portion at the upper end is covered with a back cushion, etc., so that the appearance does not deteriorate, but it is covered with a back cushion, etc. The bent portion at the lower end, which is difficult to be exposed, is exposed behind the backrest, so that the appearance of the chair when viewed from the rear is deteriorated.
In particular, when the back plate is formed of a metal plate, the bent end is exposed and the appearance is deteriorated.

  The present invention has been made in view of the above problems. Even when the seat body and the backrest are separated and the backplate of the backrest is made of metal, the bent portion at the lower end of the backplate is rearward. An object of the present invention is to provide a backrest structure for a chair that is not exposed and can improve the appearance of the backrest.

According to the present invention, the above problem is solved as follows.
(1) In a chair in which a seat body and a backrest are attached to a leg frame so that a lower part of the backrest is positioned below a rear end of the seat body, a metal back plate of the backrest The lower end is bent in a forward arc shape below the seat body, and both side ends of the back plate including the bent portion are opposed to a pair of left and right back frames in the backrest. It is fitted into a concave groove provided on the surface and facing in the vertical direction .

( 2 ) In the above item (1 ) , the lower end of the back plate is bent until it has a substantially circular shape, and the upper end of the back plate is also bent backward in a generally circular shape so that the upper and lower bent portions are As attachment parts, both side ends are fitted onto a pair of upper and lower horizontal hooks screwed to the left and right back frames, respectively.

( 3 ) In the above item ( 2 ), the bent portion at the upper end of the back plate is covered with a cushion material provided on the front surface of the back plate.

According to the first aspect of the present invention, the lower end of the back plate is bent in a forward arc shape, and the bent portion is formed at an inconspicuous corner between the lower rear end of the seat body and the lower front end of the backrest. Therefore, even if the back plate is made of metal separated from the seat body, the bent portion is not exposed to the rear of the chair, and the appearance is improved.
Further, since both side end portions including the forward arc-shaped bent portion of the back plate are fitted and hidden in the concave grooves on the opposite surface of the back frame, the appearance is good and there is no fear of wobbling in the front-rear direction.

According to the second aspect of the present invention, the back plate can be easily and stably attached to the back frame without using fixing means such as screws.

According to the third aspect of the present invention, the bent portion at the upper end of the back plate is completely hidden by the cushion material and is not exposed to the outside, so that the appearance is improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 is a front view of a lobby chair to which the present invention is applied, that is, a triple chair, FIG. 2 is an enlarged right side view, and FIG. 3 is an enlarged vertical side view taken along line III-III in FIG. Three identical chairs (2) having the same shape are attached to the upper part of the long leg frame (1).

  The leg frame (1) is horizontally mounted between a pair of left and right support legs (3) and (3) made of an aluminum alloy or the like, which are widened with an obtuse angle in the front-rear direction, and upper ends thereof. The support frame 3 is connected to the horizontal frame 4 as follows.

  As shown in FIGS. 3 and 4, the bottom surface of the left and right sides of the horizontal frame (4) to which the support leg (3) is attached has a box shape in which the left and right dimensions are larger than the front and rear dimensions and the upper surface is open. The mounting bracket (5) is fixed by welding all the front, rear, left and right contact portions with the horizontal frame (4) so that the lower part of the horizontal frame (4) is slightly fitted therein. Yes.

  At the upper end of the support leg (3), a box-like support portion (6) having an open upper surface, which can accommodate the mounting bracket (5) with a slight margin, is integrally formed.

  The dimension between the standing pieces (6a) and (6a) facing the front and rear of the support portion (6) is such that the horizontal frame (4) can be fitted from above, and the standing pieces (6b) (6b) ( At the upper end of 6b), a downward arcuate groove (7) is formed into which the substantially lower half of the horizontal frame (4) is fitted.

  The bottom plate (5a) of the mounting bracket (5) and the support substrate (6c) of the support portion (6) have four through holes (8) and stepped holes (9) arranged in the front, rear, left and right directions, respectively. A nut (10) is welded to the upper surface of the formation portion of each through hole (8) of the bottom plate (5a).

  The mounting bracket (5) is accommodated in the support portion (6) of the support leg (3), and the bottom plate (5a) is placed on the support substrate (6c), and the horizontal frame ( 4) After fitting the lower half, insert the hexagon socket bolt (11) inserted from below into the stepped hole (9) of the support substrate (6c) and the through hole (8) of the bottom plate (5a). Then, by screwing and tightening the nut (10), the lower surfaces of both side portions of the horizontal frame (4) are firmly coupled to the upper end of the support leg (3).

  A pair of left and right brackets (12) and (12) are fixed to the upper portion of the horizontal frame (4) for each chair (2).

  As shown in FIG. 3, each bracket (12) is inwardly facing the upper and rear ends of the vertical substrate (12a) facing the front and rear direction of a metal plate having a right triangle in which the upper side and the rear side are orthogonal to each other. The seat mounting piece (12b), which is bent at a right angle to the horizontal, and the back mounting piece (12c), which is substantially vertical below it, are integrally connected to each other. In the state where the upward arc-shaped concave groove (13) formed substantially at the center lower part in the front-rear direction of 12a) is fitted to the substantially upper half of the horizontal frame (4), the contact portions are welded to each other. It is fixed by. The corner where the rear end of the seat mounting piece (12b) and the upper end of the backrest mounting piece (12c) are orthogonal is also fixed by welding.

  On the upper surface of the seat mounting piece (12b) of the left and right brackets (12), the lower surfaces of both side end portions of the seat frame (16) of the seat body (15) having the seat cushion (14) mounted on the upper surface are inserted from below. Are fixed by a plurality of screws (17).

  Further, as shown in FIGS. 5 and 6, the left and right sides of the backrest (18) are shown on the rear surfaces of the backrest mounting pieces (12c) of the left and right brackets (12). The front face of the slightly thick inward mounting part (19a) formed at the lower end of the back frame (19) on both ends is a female screw hole (20) (20) facing the front and rear two holes formed in it. The bolt (21) (21) inserted from the front of the backrest mounting piece (12c) is screwed and tightened so that the lower part of the back frame (19) is lower than the rear end of the seat (15). It is fixed so that it is located.

  In order to facilitate the mounting operation of the back frame (19), the locking means that engage with each other on the opposing surfaces of the backrest mounting piece (12c) and the inward mounting portion (19a), ie, FIG. As shown, a downward hook-like locking hook (22) projects from the front surface of the inward mounting portion (19a) of the back frame (19), and a slit-like engagement with the backrest mounting piece (12c). When the hole (23) is drilled and the locking hook (22) is engaged with the lower edge of the engagement hole (23), the bolt insertion hole (illustrated) drilled in the backrest mounting piece (12c) (Omitted) and the female screw hole (20) of the inward mounting part (19a) are aligned with each other, so that the bolt (21) of the bolt (21) can be used without other workers supporting the back frame (19) by hand. Tightening work can be easily performed by one person.

  Contrary to the above, the locking hook (22) is provided on the back surface of the back mounting piece (12c), and the engagement hole (23) is provided on the inward mounting portion (19a) of the back frame (19). May be.

  As shown in FIGS. 5, 6 and 8, the opposite sides of the upper and lower ends of the left and right back frames (19) are formed with opposite ends of pipe-shaped reeds (24) and (24) on both sides thereof. Therefore, the screw (25) is coupled by screwing a bolt (27) inserted from the outside into the stepped hole (26) of the back frame (19).

  As shown in FIGS. 9 and 10, an upper mounting portion (28a) in which a metal back plate (28) made of a punching plate is curled in a rearward arc shape at the upper end thereof is provided on the upper and lower reeds (24). ) And the lower mounting portion (28b) curled in a forward arcuate shape at the lower end, respectively, and the lower mounting surface (24). The upper and lower mounting portions (28a) and (28b) have the same curvature as the outer diameters of the upper and lower horizontal bars (24) and can be locked to them, for example, approximately 2 on the outer periphery of the horizontal bar (24). / 3 curled in an arc shape so that it can be fitted. The upper and lower attachment portions (28a) and (28b) may be curled until they are substantially circular.

  Both side portions of the back plate (28) are fitted in concave grooves (29) formed on the opposing surfaces of the left and right back frames (19).

  The back plate (28) is pre-fitted to the upper and lower reeds (24) before the left and right back frames (19) are joined together by the upper and lower reeds (24).

  A back cushion (30) is attached to the front surface above the seat (15) of the back plate (28), and a headrest (31) made of a cushion material is attached to the upper end of the upper side ( 24) and the upper mounting portion (28a) of the back plate (28) fitted thereto are mounted so as to be wrapped from both the front and rear sides (see FIG. 9).

  As shown in FIGS. 11 and 12, the lateral frames (4) on both sides of the chair (2) are made of an aluminum alloy or the like having an inverted equilateral triangular shape with an elbow pad (32) attached to the upper surface. The following armrest (33) is attached as follows.

  On the upper surface of the attachment portion of each armrest (33) in the horizontal frame (4), a support metal fitting (34) having a U-shaped cross-section in a side view is substantially the same as the outer diameter of the horizontal frame (4). The contact portion between the front and back downward pieces (34a) and the horizontal frame (4) is fixed by welding.

  Insertion holes (35) and (35) which are aligned with each other are formed in the center portion of the support metal fitting (34) and the lateral frame (4) opposite to the center portion so as to penetrate in the vertical direction. ) Has a metal pipe-shaped spacer (36) facing vertically, with its upper end slightly protruding above the upper surface of the support fitting (34), and its lower end being an insertion hole (35 in the lower part of the horizontal frame (4)). ), And the upper protruding end is fixed to the upper surface of the support fitting (34) by welding.

  The bottom surface of the mounting base (33a), which is connected to the lower end of the armrest (33) and has a longitudinal dimension slightly larger than the outer diameter of the horizontal frame (4), faces the top of the horizontal frame (4). It has an upward arc shape that can be accommodated by fitting the metal fitting (34), and the back end surface forms a flat surface that comes into contact with the upper surface of the support metal fitting (34). A concave portion (38) having an upward relief groove (37) into which the concave portion is recessed is formed.

  Further, a female screw hole (39) having a lower end opened in the center of the mounting base (33a) is formed in the vertical direction.

To attach the armrest (33), the recess (38) of the mounting base (33a) is fitted to the support fitting (34) and supported by the upper surface, and then the insertion hole ( The hexagon socket head cap screw (40) inserted from 35) is inserted into the spacer (36), screwed into the female screw hole (39) of the mounting base (33a), and tightened. At this time, the head of the bolt (40) is located in the horizontal frame (4) and is not exposed to the outside.
Thereby, even if a horizontal frame (4) consists of one steel pipe, an armrest (33) can be stably attached to this.

  Covers (41) are fitted into openings at both ends of the horizontal frame (4).

  If a long spacer (36) as described above is used, it will act as a guide and the bolt (40) will be tightened easily. Bolts that penetrate the frame (4) are directly screwed into the female screw holes (39), or bolts are inserted into the female screw holes (39) from the upper inner surface of the horizontal frame (4) via a washer that is curved in an arc shape. Sometimes they are screwed together.

  As described above, in the chair of the above embodiment, the separate seat (15) and backrest (18) are attached to the pair of left and right common brackets (12). The number of points and assembly man-hours are reduced.

  Moreover, since the front surface of the lower end of the backrest (18) is attached to the rear end of the bracket (12) below the rear end of the seat (15), the bracket (12) and the lateral frame (4) It is possible to provide a chair that is inconspicuous because it is positioned in front of the lower part of the backrest (18), has a good appearance, and is excellent in design.

  Furthermore, since the female screw hole (20) facing the front-rear direction is provided on the front surface of the lower end of the back frame (19), the female screw hole (20) from the front of the backrest mounting piece (12c) of the bracket (12). The back frame (19) of the backrest (18) separately from the seat body (15) can be easily fixed to the bracket (12) by screwing the bolt (21) to the bracket (12). 21) cannot be seen from the side, so it looks better.

  The back plate (28) is fitted with concave grooves (29) formed on opposite surfaces of the left and right back frames (19) at both side ends, and curled mounting portions (28a) (28b) at both upper and lower ends. Because it is fitted and attached to a pair of upper and lower ridges (24) that connect the upper and lower opposing surfaces of the back frame (19), it is easy and stable without using fixing means such as screws. Can be installed.

  In addition, the lower mounting portion (28b) of the back plate (28) is curled in a forward arc shape so that the curled mounting portion (28b) is not exposed behind the back plate (28). Moreover, since the seat body (15) is located in an inconspicuous corner between the lower rear end of the seat body (15) and the front lower end of the backrest (18), the appearance is improved.

  The upper part of the box-shaped mounting bracket (5) whose upper surface is opened is slightly fitted to the lower surface of the tubular horizontal frame (4), and all contact parts are welded to form the upper part of the support leg (3). In the state where the mounting bracket (5) is fitted in the box-shaped support portion (6) whose upper surface is opened, the bottom plate (5a) of the mounting bracket (5) and the support substrate (6) 6c) is coupled with the bolt (11) and the nut (10), and the horizontal frame (4) is fixed to the upper part of the support leg (3). It becomes easy to position the mounting part 3).

  The mounting bracket (5) is firmly fixed to the horizontal frame (4) by welding, and the mounting bracket (5) and the support portion (6) of the support leg (3) are also provided with four bolts (11 ) And nut (10) so that the horizontal frame (4) is supported against the support leg (3) even if rotational force from a plurality of seats (15) acts on the horizontal frame (4). There is no fear of rotating.

  As described above, the present invention can be applied to a normal single chair in addition to a chair such as a lobby chair in which a plurality of single chairs (2) are attached to a leg frame (1) that is long in the left-right direction. Of course.

It is a front view of a triple chair to which the present invention is applied. Similarly, it is a right side view. It is the III-III line enlarged vertical side view of FIG. It is the IV-IV line expansion vertical rear view of FIG. It is a VV line enlarged vertical front view similarly. FIG. 6 is a cross-sectional plan view taken along line VI-VI in FIG. 5. It is a VII-VII line vertical side view similarly. It is the VIII-VIII line enlarged vertical front view of FIG. It is the IX-IX line expansion vertical side view of FIG. FIG. 6 is an enlarged vertical sectional side view taken along line XX in FIG. 5. It is a disassembled perspective view of the armrest attachment part of a chair. Similarly, it is an enlarged side view showing a part of the armrest attachment part in a longitudinal section.

(1) Leg frame
(2) Chair
(3) Support legs
(4) Horizontal frame
(5) Mounting bracket
(5a) Bottom plate
(6) Support part
(6a) (6b) Standing piece
(6c) Support substrate
(7) Groove
(8) Through hole
(9) Stepped hole
(10) Nut
(11) Bolt
(12) Bracket
(12a) Board
(12b) Seat mounting piece
(12c) Backrest mounting piece
(13) Groove
(14) Seat cushion
(15) Seat
(16) Seat frame
(17) Screw
(18) Backrest
(19) Back frame
(19a) Inward mounting part
(20) Female thread hole
(21) Bolt
(22) Locking hook
(23) Engagement hole
(24) Yokohama
(25) Female thread
(26) Stepped hole
(27) Bolt
(28) Backboard
(28a) Upper mounting part
(28b) Lower mounting part
(29) Concave groove
(30) Back cushion
(31) Headrest
(32) Elbow pad
(33) Armrest
(33a) Mounting base
(34) Support bracket
(34a) Downward piece
(35) Insertion hole
(36) Spacer
(37) Escape groove
(38) Recess
(39) Female thread hole
(40) Bolt
(41) Cover

Claims (3)

In a chair in which a seat body and a backrest are attached to a leg frame so that a lower portion of the backrest is positioned below a rear end of the seat body, a lower end of a metal back plate in the backrest is provided. Below the seat body is bent in a forward arc shape, and both end portions of the back plate including the bent portion are provided on opposite surfaces of the back frame facing the pair of left and right in the backrest. A backrest structure of a chair characterized by being fitted and held in a concave groove facing upward and downward . Bend the lower end of the back plate until it has a generally circular shape, and also fold the upper end of the back plate backward in a generally circular shape, with the upper and lower bent portions as the mounting portions for the back plate, backrest structure of claim 1 Symbol placement of chair fitted outside each lateral rod of the upper and lower pair which is screwed to the frame. The backrest structure of the chair according to claim 2 , wherein the bent portion at the upper end of the back plate is covered with a cushion material provided on the front surface of the back plate.

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