JP4133067B2 - Chair backrest device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a chair backrest device to which a lumbar support having a novel mechanism is attached.
[0002]
[Prior art]
When attaching the lumbar support to the back frame of the backrest device, conventionally, the left and right ends of the lumbar support are attached to the left and right frames of the back frame, or the upper and lower ends of the vertical support rod that supports the lumbar support are It was attached to the frame.
However, in any of the above cases, the optimal lumbar support function desired does not necessarily have a lumbar support function that can sufficiently cope with various differences depending on the seating posture of the seated person and individual differences. It was.
[0003]
For example, when seated in a tilted position, it is desirable that the lumbar support function works with a forward upward angle and a magnitude of force that differ depending on the tilt angle. However, with conventional lumbar support, this point is not always enough. It was not reached. Further, in the case where the left and right ends of the lumbar support are attached to the left and right frames of the back frame, it may be difficult to smoothly adjust the lumbar support in the vertical direction.
[0004]
[Problems to be solved by the invention]
In view of the above-described situation, the present invention enables a lumbar support function to be exhibited at a desired different forward-upward angle and magnitude of force in accordance with the rearward tilt angle of the back and waist that contacts the seated lumbar support. An object of the present invention is to provide a chair backrest device that can easily adjust the vertical position of the lumbar support.
[0005]
[Means for Solving the Problems]
According to the present invention, the above problem is solved as follows.
(1) In the back frame the outer peripheral portion is fixed a sheet-like member, the rear surface side of the sheet-like member, together to a back frame and integrally toward the lower portion of the back frame upward, downward wider, upward A lumbar support supporting portion that is formed so as to be narrower and whose upper end forms a free end is extended, and a chair backrest device is provided in which the lumbar support is attached to the lumbar support supporting portion.
[0006]
(2) In the above item (1), the sheet-like member is a net member that can be elastically deformed.
[0007]
(3) In the above item (1) or (2), the lumbar support support portion is elastically deformable rearward.
[0008]
( 4 ) In any one of the above items (1) to ( 3 ), the lumbar support is moved up and down relatively with respect to the lumbar support support portion so that the position can be adjusted.
[0009]
( 5 ) In any one of the above items (1) to ( 4 ), a rail portion facing in the vertical direction is provided on the front side of the lumbar support support portion, and the engagement portion provided on the rail portion and the lumbar support The lumbar support can be adjusted stepwise in the vertical direction by elastically engaging the engaged portion provided on the rear surface side.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
1 and 2 are a front view and a side view, respectively, of a chair provided with a backrest device according to an embodiment of the present invention.
As shown in FIGS. 1 and 2, the chair (1) has left and right side walls (4a) of a support base (4) fixed to the upper end of a pedestal (3) erected at the center of the leg (2). ) (4a), a pair of left and right backrest support rods (6) and (6) for supporting the backrest (5) are attached, and the support base (4) is mounted via the seat support rods (7a) and (7b). It is formed by attaching a seat (8) above.
[0011]
The left and right back support rods (6) and (6) are substantially L-shaped in a side view, and the left and right cylindrical portions (6a) and (6a) provided at the front end are formed on both side walls of the support base (4). (4a) (4a) is fixed to the support shaft (9) protruding left and right, and the backrest (5) and the backrest support rods (6) (6) are integrated with the support shaft (9). And can be tilted backward and downward.
In addition, urging means for returning the back tilted backrest (5) and the backrest support rod (6) is provided inside the support base (4).
[0012]
The backrest (5) is composed of a back frame (10) and a sheet-like member (11) stretched on the back frame (10). The back frame (10) is provided with a lumbar support (12). It has been.
[0013]
FIG. 3 is a front perspective view of the back frame (10) provided with the lumbar support (12) as seen from the lower side, and FIG. 4 is an exploded view of the main part of the main part in FIG. 8 is a longitudinal sectional view taken along line VIII-VIII in FIG.
[0014]
In the back frame (10), the upper and lower frames (10a) and (10b) are curved outward, have a substantially rectangular shape with a wide upper part in the front view, and protrude almost a quarter of the lower part in the side view. The shape is a forward-facing square shape, and approximately one sixth of the upper part is inclined backward and upward.
[0015]
A lumbar support support portion (13) is integrally extended upward at the lower center of the back frame (10), and the lumbar support support portion (13) is attached to the lumbar support support portion (13). .
The lumbar support support portion (13) includes a lumbar support support body (14) and a rail portion (15).
[0016]
The lumbar support support main body (14) has a substantially triangular shape that is wide at the bottom and narrows toward the top, and a pair of left and right upper and lower for supporting the rail portion (15) at the center of the front surface. Supporting wires (16) and (16) facing in the direction are provided, and screw holes (17) and (17) are screwed up and down between the left and right support wires (16) and (16).
[0017]
The rail portion (15) has a vertically long rectangular plate shape, and a pair of left and right vertical slits (18) (18) are formed slightly above the center in the vertical direction. These slits (18) ( An engaging projection (19) is provided in the center between 18).
[0018]
The rail portion (15) is wider than the width between the left and right support wires (16), (16) in the lumbar support support body (14), and the rail portion (15) is connected to the left and right support wires ( 16) As shown in FIG. 8, the two screws (20) and (20) are inserted through the through holes (21) and (21) provided at the top and bottom of the rail part (15) as shown in FIG. The lumbar support support body (14) is fastened to the screw holes (17) and (17) and is screwed to the lumbar support support body (14).
The lumbar support (12) includes a lumbar support body (22) and a cushion member (23).
[0019]
FIG. 5 is a rear view of the lumbar support body (22).
The lumbar support body (22) has operating handles (24) and (24) extending on the left and right sides of a horizontally long inverted triangle, and a vertically movable rail (25) at the bottom of the rear, with its lower end at the bottom. Are integrally attached so as to protrude.
[0020]
6 and 7 are a cross-sectional view taken along line VI-VI and a cross-sectional view taken along line VII-VII in FIG.
As shown in FIGS. 5 to 8, the movable rail (25) is located above and below the left and right edges of a vertically long plate (27) in which a plurality of engaged grooves (26) facing the left and right are provided in the vertical direction. A pair of locking pieces (28) and (28) each having an inward locking claw (28a) at the tip are provided.
[0021]
As shown in FIGS. 4 and 8, the cushion member (23) is formed by attaching a horizontally long substantially inverted cushion material (30) to the front surface of the substantially identical base plate (31).
[0022]
FIG. 9 is a partially enlarged view within a broken-line circle in FIG.
As shown in FIG. 9, the base plate (31) has a through hole (32), and the rear surface of the cushion material (30) has a through hole (32) at a position corresponding to the through hole (32). ) Having a diameter larger than that of the hole (33), and both of the through hole (32) and the hole (33) step around the through hole (32) on the front surface of the base plate (31). A mounting hole (35) serving as a portion (34) is formed.
[0023]
On the other hand, a retaining member (36) is fixed to the lumbar support body (22) with a screw (37) at a position corresponding to the mounting hole (35). The retaining member (36) is provided with a locking claw (36a) that is elastically biased outward on the outer peripheral surface thereof. The retaining member (36) is inserted into the mounting hole (35) provided on the rear surface of the cushion member (23), and the locking claw (36a) of the retaining member (36) is inserted into the mounting hole (35). The cushion member (23) is integrally attached to the lumbar support main body (22) by being engaged with the step portion (34).
[0024]
The lumbar support (12) composed of the cushion member (23) and the lumbar support body (22) is a locking claw (28a) (28a) of the left and right locking pieces (28) (28) in the movable rail (25). Is secured to the left and right edges (15a) and (15a) of the rear surface of the rail part (15) in the lumbar support support part (14), thereby sliding the movable rail (25) onto the rail part (15) in the vertical direction. It is movably fitted.
[0025]
As shown in FIG. 8, since the rail part (15) is attached to the lumbar support support body (14) so as to be slightly curved forward, the left and right slits (18) ( 18) The engaging projections 19 provided between them (see FIG. 4) are elastically biased forward. Therefore, by moving the lumbar support (12) to an appropriate position in the vertical direction, the engaging protrusion (19) is elastically engaged with any of the engaged grooves (26) provided in the vertical direction on the movable rail (25). Accordingly, the vertical position of the lumbar support (12) is stably held at that position.
[0026]
On the other hand, when trying to move the lumbar support (12) up and down against the elastic urging force, the engagement protrusions (19) provided between the left and right slits (18) and (18) As the plate portion between 18) and 18 retreats with the backward curve, the engagement with the engaged groove (26) is released, and the lumbar support (12) can be moved up and down freely.
[0027]
Next, the lumbar support (12) is moved up and down to determine a desired new vertical position, and the engagement protrusion (19) is elastically engaged with the other engaged groove (26) closest to the position. Thus, the lumbar support (12) is again stably held at that position.
On the back frame (10), a sheet-like member (11), for example, a net member (38) is stretched.
[0028]
10, FIG. 12, and FIG. 13 are a cross-sectional view taken along line X-X, a vertical cross-sectional view taken along line XII-XII, and a vertical cross-sectional view taken along line XIII-XIII in FIG.
The frame member (39) forming the back frame (10) has an inner edge ridge (40) and an outer edge protrusion, the cross-section of which is inclined forward from the outside toward the inside, and the inner and outer edges respectively face the front. It is formed from a thick and rigid member provided with a strip (41).
[0029]
As shown in FIG. 3, the front surface of the back frame (10) is provided with forward-facing locking projections (43) having screw holes (42) at appropriate positions over the entire circumference of the back frame (10). Yes.
The net member (38) is stretched on the back frame (10) using the fixed frame (44).
[0030]
FIG. 11 is an exploded view showing the back frame (10) and the fixed frame (44) in FIG. 10 separately.
The fixed frame (44) is a frame-like object that is fitted over the entire circumference of the front surface of the back frame (10), and the cross section of the fixed frame (44) is the inner edge ridge (40 in the frame material (39) of the back frame (10). And a frame member (45) having a width that can be fitted between the outer edge protrusion (41), and the rearward holding groove (46) over the entire circumference in the vicinity of the outer edge of the rear surface of the frame member (45). The rear edge holding groove (46) forms an outer edge standing piece (47). Further, inward of the holding groove (46) on the rear surface of the frame member (45), the inside is enlarged in a position corresponding to the locking projection (43) in the back frame (10), and a step portion ( A locking hole (49) having 48) is provided.
[0031]
The net member (38) is stretched on the back frame (10) by the following procedure.
A retaining member (50) is fastened to the front end of the locking projection (43) of the back frame (10) with a screw (51).
The retaining member (50) is provided with a locking claw (50a) which is elastically biased outward on the outer peripheral surface thereof.
[0032]
Next, the peripheral part of the net member (38) is brought into contact with the front surface and the outer surface of the fixed frame (44), and then the outer end thereof is bent inward to be fixed to the outer peripheral edge of the net member (38). The inserted insertion piece (52) is inserted into the holding groove (46).
[0033]
Next, with the rear surface of the fixed frame (44) facing the front surface of the back frame (10), the locking projection (43) with the retaining member (50) attached to the front end of the back frame (10) is secured. The locking claw (50a) of the retaining member (50) is engaged with the stepped portion (48) of the locking hole (49) by being fitted into the locking hole (49) of the fixed frame (44). Then, the rear surface of the fixed frame (44) is brought into close contact with the front surface of the back frame (10) to integrate the back frame (10) and the fixed frame (44).
[0034]
As a result, the insertion piece (52) fixed to the outer peripheral edge of the net member (38) is fixed in a state of being inserted into the holding groove (46), so that the net member (38) is fixed to the back frame. Stablely stretched on the front of (10).
[0035]
As shown in FIG. 2, the upper part of the backrest (5) is provided with the tip of a support (53) projecting rearward from the rear surface of the upper part in the left-right direction provided at the upper part of the backrest support (6). It is attached to the back support rod (6) by being pivotally supported by the mounting shaft (54).
[0036]
The lower part of the backrest (5) consists of a support (55) projecting rearward from the rear surface of the lower part and a support (56) projecting forward from the lower front face of the backrest support support (6). By connecting the tips of both supports (55) and (56) to each other and changing the front and rear positions of the lower part of the backrest (5) with the operating lever (57), the back tilt angle of the backrest (5) is finely adjusted. It is attached to the backrest support ridge (6) in such a way that it can be adjusted.
[0037]
【The invention's effect】
According to the present invention, the following effects can be achieved.
(1) According to the first aspect of the present invention, the lumbar support support portion extends integrally with the back frame from the lower part of the back frame upward, and its upper end forms a free end. The upper end, which is the free end of the lumbar support support portion, tilts backward according to the back tilt angle of the person's back and waist, and the restoring force from the tilted state also increases. In particular, the lumbar support support portion is formed so that the lower portion is wider and narrower toward the upper portion, so that it can be elastically deformed rearward and has a desired restoring force depending on the angle of backward tilt. The lumbar support support portion having the above can be easily formed.
Therefore, the lumbar support exhibits a lumbar support function with a different desirable forward upward angle and magnitude of force depending on the rearward tilt angle.
In addition, since the lumbar support is provided on the rear surface side of the sheet-like member whose outer peripheral portion is fixed to the back frame, when the seated person tilts backward to some extent and the lumbar support function is required, The function is often demonstrated.
[0038]
(2) According to the invention described in claim 2, when the seat occupant is less inclined backward, the back and waist portion is supported by the elastically deformable net member, and when the backward inclination is increased, the lumbar support function in the present invention is exhibited. The effect of the present invention can be exhibited more effectively by supporting the back and waist.
[0039]
(3) According to the invention described in claim 3, the effect of the invention described in claim 1 can be exhibited satisfactorily.
[0040]
( 4 ) According to the invention of claim 4 , the lumbar support function can be exhibited at the vertical position desired by the seated person.
[0041]
(5) According to the fifth aspect of the present invention, in addition to the effects of the invention of claim 5, wherein the adjustment it is possible to easily perform the vertical position of the lumbar support in the vertical position after adjusting, lumbar support Can be held stably.
[Brief description of the drawings]
FIG. 1 is a front view of a chair including a backrest device according to an embodiment of the present invention.
FIG. 2 is a side view of the same.
FIG. 3 is a front perspective view of a back frame provided with a lumbar support as viewed from a slightly lower side.
FIG. 4 is an exploded view showing a main part in FIG. 3 in an exploded manner.
FIG. 5 is a rear view of the lumbar support main body.
6 is a cross-sectional view taken along line VI-VI in FIG.
7 is a cross-sectional view taken along line VII-VII in FIG.
8 is a longitudinal sectional view taken along line VIII-VIII in FIG.
9 is a partially enlarged view inside a broken-line circle in FIG.
10 is a cross-sectional view taken along line X to X in FIG.
11 is an exploded view showing the back frame and the fixed frame in FIG. 10 separately.
12 is a longitudinal sectional view taken along line XII-XII in FIG.
13 is a longitudinal sectional view taken along line XIII to XIII in FIG.
[Explanation of symbols]
(1) Chair
(2) Leg
(3) pedestal
(4) Support base
(4a) Side wall
(5) Backrest
(6) Back support heel
(6a) Tube part
(7a) (7b) Seat support frame
(8) Seat
(9) Support shaft
(10) Back frame
(10a) Upper frame
(10b) Bottom frame
(11) Sheet member
(12) Lumber support
(13) Lumber support support
(14) Lumber support support body
(15) Rail part
(15a) Edge
(16) Support line
(17) Screw hole
(18) Slit
(19) Engagement protrusion
(20) Screw
(21) Through hole
(22) Lumber support body
(23) Cushion member
(24) Operation handle
(25) Movable rail
(26) Engagement groove
(27) Plate
(28) Locking piece
(28a) Locking claw
(29) Retaining member
(30) Cushion material
(31) Base plate
(32) Through hole
(33) Hole
(34) Step
(35) Mounting hole
(36) Retaining member
(36a) Locking claw
(37) Screw
(38) Net member
(39) Frame material
(40) Inner edge ridge
(41) Outer edge ridge
(42) Screw hole
(43) Locking projection
(44) Fixed frame
(45) Frame material
(46) Backward holding groove
(47) Outer edge upright piece
(48) Step
(49) Locking hole
(50) Retaining member
(50a) Locking claw
(51) Screw
(52) Insert
(53) Support
(54) Mounting shaft
(55) (56)
(57) Control lever

Claims (5)

In the back frame the outer peripheral portion is fixed a sheet-like member, the rear surface side of the sheet-like member, together to a back frame and integrally toward the lower portion of the back frame upward, downward wider, narrower more upward A backrest device for a chair, characterized in that a lumbar support supporting portion formed so as to have an upper end and a free end is extended, and the lumbar support is attached to the lumbar support supporting portion.   2. The chair backrest device according to claim 1, wherein the sheet-like member is an elastically deformable net member.   The backrest device for a chair according to claim 1 or 2, wherein the lumbar support support portion is elastically deformable rearward. The chair backrest device according to any one of claims 1 to 3 , wherein the lumbar support is vertically movable relative to the lumbar support support portion so that the position thereof can be adjusted. By providing a rail portion facing in the vertical direction on the front side of the lumbar support support portion, and engaging the engagement portion provided on the rail portion and the engaged portion provided on the rear surface side of the lumbar support, The backrest device for a chair according to any one of claims 1 to 4 , wherein the lumbar support is adjustable stepwise in the vertical direction.

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