JP2022168245A - Chair with lumbar support unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lumbar support unit excellent in following ability to a posture change of a person who is seated on a chair.

SOLUTION: A lumbar support unit 21 comprises: a lumbar guide 22 fixed to a chair; and a pad body which is fitted to the lumbar guide 22 in a manner of capable of being lifted up/down. The pad part has a pad body 27 which is long in a lateral direction. A backrest 2 is varied in a shape in plan view by twisting of a body of a person who is seated on a chair, however, the lumbar guide 22 is fitted to a pole frame 13 which is fixed to a base body of a back pole 7, therefore there is no torsional deformation on a backrest 3. The pad body 27 is supported by the lumbar guide 22 through left and right spring bodies, and a shape of the pad body 27 is also varied following shape change of the backrest 3. Therefore, fitness of the pad body 27 to a body of a person who is seated on the chair.

SELECTED DRAWING: Figure 14

COPYRIGHT: (C)2023,JPO&INPIT

Description

The present invention relates to a chair with a lumbar support device.

Providing a lumbar support device on the back of a chair is widely practiced. The lumbar support device has a pad body, and there are those with a constant height of the pad body and those with an adjustable height of the pad part.

Lumbar support devices have a wide variety of structures, and as an example, Patent Document 1 discloses that a pad body is attached to a support member so as to be movable back and forth, and is supported by left and right spring bodies (compression coil springs). there is

To be precise, in Patent Document 1, while a rearward-facing cylinder is provided on the rear surface of the pad portion, a forward-facing cylinder having a smaller diameter than the rearwardly-facing cylinder of the pad portion is provided on the front surface of the support member provided on the back frame. A spring body is provided integrally between the two cylinders to elastically support the backward movement of the pad body. A plate is provided, and a screw with a head is inserted into the forward-facing cylindrical body from behind and passed through the front plate, and this screw is screwed into the pad portion.

Now, lumbar support devices that can adjust the height of the pad body are widely used. often constant. On the other hand, in Patent Document 1, since the pad portion retreats against the spring body, it is characterized by high cushioning properties.

U.S. Patent Publication No. 2017/023401021

Now, a person sitting on a chair does not always face only forward, but sometimes faces sideways.
That is, the body may twist to the left or right. Alternatively, the upper body may be tilted left or right. In other words, a person sitting on a chair may change his or her posture while pressing the upper body against the backrest.

In this case, when the shape and posture of the backrest in a plan view are deformed according to the twisting and tilting of the body, the fit to the body is remarkably enhanced, and a comfortable feeling of use can be obtained. When the planar view shape and posture of the backrest changes due to changes in the posture of the person, the planar view posture of the pad part of the lumbar support device changes to follow the change in the shape and posture of the backrest, further improving the usability. can.

However, the backrest of Patent Document 1 does not change its plan view shape or posture due to the twisting of the seated person's body. It is considered that the fit is inferior.

In addition, in Patent Document 1, the lumbar support device is attached to the back frame of the backrest, and the pad portion simply retreats against the spring body. If the pad part or the right part is deformed so as to bend backward, the left end or the right end of the pad part may be strongly stretched against the user's body, causing an uneven contact phenomenon, which may reduce the feeling of use.

The present invention is made to improve such a situation.

The lumbar pad device of the present invention is as claimed in claim 1,
"A backrest comprising a back frame with a front and rear opening and a flexible and deformable backrest member, and a lumbar support device arranged behind the backrest member independently of the backrest,
The backrest may change its shape or posture in plan view when the body pressure of the seated person is applied unevenly in the left-right direction.
The lumbar support device has a laterally elongated pad section on which the body pressure of a seated person is applied via the backrest material, and a support section to which the pad section is attached so as to be movable back and forth. , the pad portion is arranged to be movable relative to the back frame, and the pad portion is supported by the support portion via left and right spring bodies so that the posture in a plan view changes following a change in shape or posture of the backrest. supported."
It is configured.

The present invention can be developed in various ways. Examples thereof are specified in claims 2 and below. Of these, the invention of claim 2 is characterized in that, in claim 1,
"The support part includes a vertically elongated lumbar guide, the upper end of the lumbar guide is connected to the back support to which the back frame is attached, and the lower end of the lumbar is connected to the left and right of the lower part of the back frame. While connected to the middle section,
The pad portion includes a left and right long frame body that protrudes greatly to the left and right outer sides of the left and right spring bodies in a state of covering the lumbar guide from behind, and a front member attached to the frame body in a state of covering the lumbar guide from the front. and a pad body that spans the left and right ends of the frame body,
Between the hollow portion formed by the frame body and the front member and the lumbar guide,
A gap is formed to allow horizontal rotation of the frame body and the front member.”
It is configured. In the present application, "connection" includes both a relatively movable state and a fixed state.

In addition, the invention of claim 3 is, in claim 1,
"The back frame is allowed to change its posture following changes in the posture of a seated person by connecting the left and right intermediate portions of its lower end to the lower support,
The support portion of the lumbar support device includes a vertically elongated lumbar guide provided on the lower support body and having a free upper end, and an elevating body attached to the lumbar guide so as to be able to move up and down. , and the pad portion, which is long in the left and right direction, is attached to the elevating body so as to be horizontally rotatable.”
It is configured. Note that "posture change" includes deformation.

The invention of claim 4 is characterized in that, in any one of claims 1 to 3,
"The pad section has a pad body that rotates up and down around a horizontal axis."
It is configured.

The invention of claim 5 embodies claim 4, and in this invention,
"It is provided with an elastic body that provides resistance to the up-and-down rotation of the pad body"
It is configured.

According to the invention of claim 6, in any one of claims 1 to 5,
"In the initial state where the rearward body pressure of the seated person is not applied to the backrest, a gap is set between the pad portion and the back support material."
It is configured.

In the inventions of the present application, the backrest changes its plan view shape or plan view posture by following the torsion and inclination of the seated person's body. The device does not interfere with backrest deformation or posture changes. Therefore,
Even when the seated person twists the body or tilts left or right, a high fit can be ensured.
Moreover, since the planar view posture of the pad portion changes following the planar view shape or planar view posture of the backrest, it is possible to obtain a high fit with the pad portion.

Since the spring bodies are arranged on the left and right sides, the user's body can be stably supported without twisting or tilting the body. Therefore, the function of the lumbar support device to firmly support the lumbar vertebrae while working is ensured. Also, it is possible to ensure that the pad portion is returned to the initial posture.

The structure for horizontally rotating the pad portion can be embodied in various ways, but in claim 2, since the lumbar guide is surrounded by the hollow portion made up of the frame and the front member, there is an advantage that the number of members can be reduced and the size can be reduced. There is According to claim 2, the upper end of the lumbar guide is connected to the back support and the lower end of the lumbar guide is connected to the lower left and right intermediate portions of the back frame. The torsional deformation of the back frame in a plan view can be allowed without changing the front-rear position. As a result, it is possible to ensure that the posture of the pad body follows the posture change of the body.

Also in the structure of claim 3, since the lower end of the back frame is connected to the lower support at the left and right intermediate portions, the back frame can be deformed and changed in posture following the change in the posture of the seated person. Allowed. Furthermore, since the lumbar guide of the lumbar support device is also provided on the lower support, the distance between the lumbar guide and the backrest is kept constant, and the body support function of the pad body can be ensured. That is, it is possible to secure an accurate lumbar support function while allowing the backrest to twist.

In addition, since the upper end of the lumbar guide is a free end in claim 3, there is an advantage that the lifting body can be easily mounted, and separate members are responsible for the height adjustment mechanism and the horizontal rotation mechanism. ,
There is an advantage that the height adjustment function and the horizontal rotation function can be ensured.

In claim 4, in addition to horizontally turning (swinging left and right), the pad body swings up and down around a horizontal axis, so that the fit to the user can be improved. In this case, the stability of the pad body can be improved by applying resistance to the upward and downward rotation of the pad body with an elastic body. In particular, when a gap is provided between the pad portion and the backrest material in the initial state as in claim 6, if the initial posture is maintained by an elastic body as in claim 5, the pad body will not fall. This is particularly beneficial because it prevents

As in claim 6, if a gap is left between the back support material and the pad portion in the initial state, the back support material such as a mesh material is pushed by the body pressure of the seated person when the person leans against the backrest. Since the back support material hits the pad body after being deformed so as to be recessed backward, there is an advantage that the cushioning property can be further improved.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows 1st Embodiment, (A) is the whole perspective view seen from this side, (B) is a partially-omission side view. (A) is a front view, and (B) is a rear view. (A) is a plan view, and (B) is a perspective view seen from behind. 1 is an exploded perspective view of a chair; FIG. It is a longitudinal side view centering on a backrest. (A) is an enlarged detailed view of the portion indicated by arrow A in FIG. 5, (B) is an enlarged detailed view of the portion indicated by arrow B in FIG. 5, and (C) is indicated by arrow C in FIG. 1 is an enlarged detailed view of the cut portion; FIG. (A) is an isolated perspective view of the lumbar support device seen from the front, (B) is an isolated perspective view of a part of the lumbar support device seen from the back, (C) is a partial front view of the lumbar guide body, ( D) is a rear view of the lock body. (A) and (B) are partially omitted separated perspective views of the lumbar support device as seen from the front, (B) is a separated perspective view of a pad portion, and (C) is a partially separated perspective view. (A) is a partial perspective view of the lumbar support device, (B) is a separated perspective view of the pad body from the lumbar frame, and (C) is a rear view of the pad body. (A) is a partial perspective view of the lumber frame, (B) is a separated perspective view of the lumber frame and the connecting bar, and (C) is a CC view of FIG. 9C with the pad body attached to the lumber frame. It is a cross-sectional view. 6 is a horizontal cross-sectional view taken along line XI-XI of FIG. 5; FIG. It is a figure which shows 2nd Embodiment, (A) is the perspective view seen from this side, (B) is the perspective view seen from the back, (C) is a side view, (D) is a rear view. It is a top view which shows a motion of a pad body. (A) is an exploded perspective view of a chair, and (B) is a perspective view showing an arrangement state of a lumbar support device. (A) is an isolated perspective view seen from the back, and (B) is an isolated perspective view of the back support and the base portion from the back. (A) is a front view of the lumbar support device, and (B) is a sectional view taken along line BB of (A). (A) is a perspective view of a lumbar support device, (B) is an isolated perspective view of the lumbar support device, and (C) is a perspective view of an upper end portion of a lumbar support. (A) is an isolated perspective view seen from the rear, and (B) is an isolated perspective view seen from the front. 17 is a cross-sectional view taken along line XIX-XIX of FIG. 16; FIG. FIG. 17 is a sectional view taken along line XX-XX of FIG. 16;

Next, embodiments of the present invention will be described based on the drawings. This embodiment is applied to a swivel chair that is frequently used in offices. In the present application, terms such as front, back, left, and right are used to specify directions, but these directions are based on the view of a person who normally sits on a chair. The front view is the direction facing the seated person.

(1).Outline of the First Embodiment First, the outline of the chair of the first embodiment will be described mainly based on FIGS. This embodiment is applied to a swivel chair that is frequently used in offices. This chair has a seat 1, a backrest 2 and a leg device 3 with casters. The leg device 3 has a leg strut 4 made of a gas cylinder, and as shown in FIG.

A tilting base 6 is attached to a portion of the fixed base 5 in front of the leg support 4, and a first shaft 7 extending in the left and right direction is provided.
(See FIG. 1B) (actually, the first shaft 7 is hidden and cannot be seen when viewed from the side). there is Therefore, the back column 8 tilts backward with the first shaft 7 as a fulcrum. The back brace 8 may be made of resin, or may be made of metal such as aluminum die-cast. The tilting base 6 is also made of metal or resin.

The backrest 2 has a structure in which a mesh material 10 is stretched on a back frame 9 which is open in the front and rear. The mesh material 10 is an example of the backrest material described in the claims. The back frame 9 is made of synthetic resin, and consists of vertically long left and right side members 11, an upper member 12 integrally connected to the upper ends thereof, a lower member 13 connected to the left and right side members 11, and the left and right side members 11. It has a middle member 14 connected to the upper part. middle member 14
is V-shaped in front view, and the lower end portion 14a of the middle member 14 and the upper end portion of the back support 8 are connected by a left-right longitudinal second shaft 15 (see FIG. 1(B)).

As partially shown in FIG. 5, the seat 1 has a structure in which a seat cushion 17 is stretched on a seat inner shell 16, and the seat inner shell 16 is attached to a seat outer shell 18 (see also FIG. 1(B)). ing. The seat outer shell 18 is composed of front and rear members 3, and a front and rear intermediate member is fixed to a seat support (not shown). , tilting backward while retreating.

As shown in FIGS. 4 and 5, the rear end of the seat outer shell 18 and the lower member 1 of the back frame 9
3 are connected by a third shaft 19 extending in the left and right direction. The side members 11 of the back frame 9 are deformable so that the side view posture and the front view posture change depending on the body pressure of the seated person.

As shown in FIG. 1(B), a forward portion 8a forming the lower end of the back support 8 is fixed to the rear end portion of the tilting base 6. As shown in FIG. A locking spring is arranged inside the fixed base 5, but is omitted in the drawing.

The backrest 2 comprises a back frame 9 and a mesh material 10. - 特許庁An edge member such as a resin tape is fixed to the outer peripheral edge of the mesh material 10 by means of a joint or the like, and the edge member is attached to the back frame 9 .

The upper portion of the back frame 9 has a constricted portion 20 that narrows inward in front view, and the middle member 14 is connected to the constricted portion 20 . Also, the side member 11 is thin, and a side cover 21 is fixed to the front surface thereof. The lower ends of the side members 11 are connected to both left and right ends of the lower member 13 with pins 22 (see FIG. 4).

As shown in FIG. 4, downward bracket portions 13 a are formed at both left and right ends of the lower member 13 of the back frame 9 , and the bracket portions 13 a are connected to the rear end of the outer shell 18 by a third shaft 19 . ing. As shown in FIG. 4, a lower cover 23 is overlapped and fixed to the lower member 13 of the back frame 9 from the front side.

(2).Overview of Lumbar Support Device The backrest 2 is provided with a lumbar support device. The lumbar support device has a pad portion 31 that supports a seated person from behind through a mesh material 10, and a lumbar guide body (lumbar support) 32 to which the pad portion 31 is attached so as to be adjustable in height. The upper end of the guide body 32 is connected to the connecting portion between the middle member 14 and the back support 8 , and the lower end of the lumbar guide body 32 is connected to the lower member 13 . Also, the lumbar guide body 32 has a strip-like shape, and is gently curved as a whole so as to protrude forward in a side view.

In the non-locking state in which the seated person is not leaning against the backrest 2, no external force acts on the lumbar guide body 32 in the vertical direction. Therefore, the front and rear positions of the pad portion 31 do not change, and the body pressure of the seated person is supported through the mesh material 10 (however, the lumbar guide body 3
Depending on the side view posture of 2, when the height changes, the front and back position may also change.)
.

When the backrest 2 tilts backward, the second shaft 15 moves downward while retreating, and the third shaft 19 also moves downward. Therefore, the distance between the second shaft 15 and the third shaft 19 varies. In this case, the distance may be widened or narrowed, and the distance is narrowed in this embodiment.

Therefore, the mesh material 10 tends to sag during rocking, but when the distance between the second shaft 15 and the third shaft 19 narrows, the degree of bending of the lumbar guide body 32 increases and the pad portion 31 is pushed forward. acts on This can prevent the mesh material 10 from becoming too loose. As a result, it is possible to prevent the holdability against the body from becoming excessively high.

The backrest 2 has a portion positioned above the upper end of the back support 8 . The upper part of the backrest 2 positioned above the upper end of the back support 8 as indicated by the black arrow in FIG. In this case, the backrest 2 can tilt backward with the second shaft 15 as a fulcrum. That is, after the back support 8 is completely tilted backward, the backrest 2 can be further tilted backward (double rocking). Therefore, high comfort can be ensured.

When the backrest 2 tilts backward about the second shaft 15, the lower end of the back frame 9 tries to rotate forward, but the lower end of the back frame 9 is restricted by the third shaft 19 so that it cannot move forward. Therefore, the chevron portion of the back frame 9 tends to spread outward and deform. In addition, the backrest 2
tilts backward, the lumbar guide body 32 is deformed to increase the degree of bending, as indicated by the black arrow in FIG. 1(B). As a result, the pad portion 31 tends to move forward, and the waist of the seated person is firmly supported.

As a result, the backrest 2 can perform primary rocking by tilting the back support 8 backward, and secondary rocking in which only the backrest 2 tilts backward after the back support 8 has fully tilted backward. Since the seat moves forward, it is possible to appropriately support the seated person's upper body in a stretched state, thereby ensuring a high level of comfort.

(3). Details of Lumbar Support Device Next, the lumbar support device will be described mainly with reference to FIG. 6 and subsequent drawings. The lumbar guide 32 is made of resin or a metal plate and has a vertically elongated band shape, but as a whole is curved forward in a side view, as shown in FIG. To be precise, the upper part is curved.
Therefore, it can be deformed by an external force applied in the vertical direction. A portion of the lumbar guide 32 in which the pad body 39 moves up and down has a substantially straight posture when viewed from the side.

An upper end portion 32 a of the lumbar guide 32 is connected to a lower end portion of the middle member 14 . That is, as shown in FIG. 6A, for example, a bearing recess 34 is formed at the lower end of the middle member 14 so as to open downward and rearward, into which the bearing boss 33 provided at the upper end of the back column 8 fits. 7 (A
) is fitted into the engagement hole 32c shown in FIG. 4A, and is held by the stopper member 35 inserted and locked between the middle member 14 and the bearing boss portion 33 so as not to come off.
The upper end portion 32a of the is fixed so as not to come off.

As shown in FIG. 6B, the lower end portion 32b of the lumbar guide 32 is sandwiched between the lower member 13 and the lower cover 23 and fixed with a screw 37 so that it cannot be removed. The upper end portion 32a of the lumbar guide 32 may be fixed to the bearing boss portion 33 of the back support 8 or the like with a fastener such as a screw, or may be fixed to the lower end of the middle member 14 with a fastener such as a screw.

For example, as shown in FIG. 7, the pad portion 31 includes a frame 38 that is long in the left and right direction while being covered by the lumbar guide 32 from behind, and the pad body 3 that is stretched over the left and right ends of the frame 38 .
9 and a front member 4 fixed to the frame 38 in a state of covering the lumbar guide 32 from the front.
0. On the other hand, the supporting portion described in the claims is composed of the lumbar guide 32 and the lifting body 41 that holds it from behind.

The pad body 39 is made of soft resin such as elastomer. The frame 38 is curved so as to be recessed toward the front in a plan view, and both left and right portions are open. Therefore, it has a spectacle shape (it does not have to be open).

The frame 38 is largely curved in plan view, whereas the pad body 39 is substantially flat. Therefore, the pad body 39 is supported by the frame 38 only at the left and right ends while the pad body 39 is supported at both ends.
installed in the As an attachment structure for the pad body 39, for example, FIGS.
) and FIG. 10, the frame 38 is formed with multistage engaging claws 42 projecting outward, while the pad body 39 is formed with pocket portions 43 into which the engaging claws 42 are inserted.

For example, as clearly shown in FIGS. 10A and 10B, the lower end of the frame 38 is the joint bar 4.
4 is connected. The joint bar 44 is formed with a hook portion 45 that engages with the engaging claw 42 at the lowermost end. Due to the presence of the joint bar 44, the frame 38 is prevented from spreading and deformation, and the bending deformation of the lower edge of the pad body 39 is prevented. When the body pressure of the seated person is applied to the pad body 39, the pad body 39 can be stretched and deformed so as to be dented backward, but the lower end edge is not deformed, and the easiness of deformation increases as it goes upward.

For example, as shown in FIG. 8, a guide wall portion 46 made up of a group of ribs is formed in the left and right intermediate portions of the frame 38, and between the left and right guide wall portions 46, there is a lifting/lowering mechanism that holds the lumbar guide 32. The front part of the body 41 is arranged. 11, the lifting body 41 has side walls 41a protruding forward on both the left and right sides of the lumbar guide 32. Left and right side walls 41a positioned in front of the lumbar guide 32 are provided on the left and right side walls 41a. are formed so as to face each other. Therefore, left and right dovetail grooves for holding the lumbar guide 32 are formed in the lifting body 41 .

As clearly shown in FIG. 11, there is a slight gap of dimension E1 between the left and right side surfaces of the lifting body 41 and the guide wall portion 46 of the frame 38 . Therefore, front member 40 and frame 38
This means that it can horizontally rotate (horizontally turn) at a certain angle, as indicated by the dashed line in FIG. 11 .

As shown in FIGS. 7(B), 8(B) and 8(C), a plurality of upper and lower outward ribs 48 protrude from the left and right side surfaces of the lifting body 41 . On the other hand, for example, as shown in FIG. 8B, frame 38
has guide walls 46 protruding forward on both the left and right sides of the lifting body 41. The guide walls 46 are composed of a group of ribs, so that grooves are formed between adjacent ribs. However, the outward rib 48 of the lifting body 41 is fitted in the groove of the guide wall portion 46 so as to be slidable back and forth. Therefore, the lifting body 41 is attached to the frame 38 so that it cannot move up and down but can move back and forth.

The lower end of the engaging claw 47 provided on the lifting body 41 is a free end, and the lower end has an inwardly projecting chevron shape. On the other hand, the lumbar guide 32 is provided with left and right concave and convex portions 49 that engage and disengage by elastically deforming the engaging claws 47 projecting forward. An uneven portion 49 is formed.).

(4) Elevation Lock Mechanism The front member 40 is arranged in front of the elevation body 41. The front member 40 is shown in FIG.
As shown in (B), it is fixed to the guide wall portion 46 of the frame 38 with left and right screws 50 . As clearly shown in FIG. 11, there is a certain amount of space E2 (several mm) between the front member 40 and the lifting body 41, and the front member 40 and the frame 38 are positioned relative to the lifting body 41 and the lumbar guide 32. can move back and forth by a certain dimension.

Further, as shown in FIGS. 8B, 8C and 11, left and right springs (coil springs) 51 are arranged between the front member 40 and the lifting body 41. As shown in FIGS. Therefore, the front member 40 is biased away from the lifter 41 and the lumbar guide 32 , and when the body pressure of the seated person is applied to the pad body 39 , the front member 40 comes into close contact with the lumbar guide 32 . A spring bearing 52 is formed between the front member 40 and the lifting body 41 . Instead of the coil spring 51, another elastic body such as rubber may be used.

As can be understood from FIGS. 8(C), 7(C), and 11, on the front surface of the lumbar guide 32, there are a center engagement groove 53 extending along the longitudinal center line and lock grooves 54 positioned on both sides thereof. is formed by a group of forward facing ribs. The center engagement groove 53 extends vertically in a long series, while the lock groove 54 is formed in multiple stages corresponding to the concave and convex portions 49 and communicates with each other.

On the other hand, as shown in FIGS. 8(A), 7(D) and 11, on the rear surface of the frame 38, a center rib 55 located behind the center engaging groove 53 and left and right outside of the center rib 55 are located. Upper and lower locking projections 56 are formed. The center rib 55 can be fitted into and removed from the center engagement groove 53, and the upper and lower lock projections 56 can be fitted into and removed from the two lock grooves 54 that are separated vertically.

That is, the vertical pitch of the lock grooves 54 is the same as the pitch of the irregularities 49 , and the interval between the upper and lower lock claws 95 is an integral multiple of the pitch of the lock grooves 54 and the irregularities 49 . When the lock projection 56 fits into the lock groove 54, the frame 38 and the pad body 39 are held so as not to move up and down.

(5) Summary of First Embodiment In this embodiment, the left and right sides of the backrest 2 can be rotated horizontally as indicated by the solid line arrow and the dotted line arrow in FIG. 1(A). Therefore, the shape in plan view changes, and the fit to the seated person is improved. This change in shape is caused not only by rocking, but also by twisting the body of the seated person or leaning left or right.

Since the lumbar guide 32 is elastically deformed and can move relative to the back frame 9, the lumbar support device prevents the backrest 2 from rocking or from twisting the body of the seated person or leaning left or right. does not interfere with changes in the shape and posture of the Therefore, the fit of the backrest 2 can be improved.

As described above, the gap of dimension E1 between the left and right side surfaces of the lifting body 41 and the guide wall portion 46 of the frame 38 allows the pad portion 31 to rotate horizontally (horizontally) at a certain angle. turning) can be done. Therefore, when a seated person twists the upper body to the left or right with the upper body in contact with the mesh material 10, or tilts the upper body to the left or right in the front view, the planar view shape of the backrest 2 changes. , the pad body 39 horizontally rotates following changes in the posture of the body and changes in the shape (or posture) of the backrest 2 . Therefore, it is possible to secure a comfortable contact feeling of the pad body 39 against the body while improving fit of the body to the backrest 2 . Therefore, it is comfortable to use.

In this embodiment, the left and right side members 11 of the back frame 9 are configured to be elastically deformed by the body pressure of the seated person and to rotate backward around the lower ends connected by the pins 22 . Therefore, when the seated person twists the upper body to the left or right, or tilts the upper body to the left or right, it can easily deform to follow the posture change of the seated person. Since the pad body 39 horizontally rotates following the deformation of the back frame 9 , the seated person does not feel the tension caused by the left or right end of the pad body 39 . For this reason, it is excellent in usability and comfortable.

In the present embodiment, since the pad body 39 moves backward by the dimension E2, it is more excellent in following the change in posture of the body, which is preferable. In addition, since the pad body 39 moves backward by the distance E2 against the elasticity of the spring 51, there is an advantage that the cushioning property can be improved regardless of the change in posture of the body.

In addition, in this embodiment, since the left and right intermediate portions of the frame 38 are located behind the lumbar guide 32, it is possible to ensure that the pad portion can be raised and lowered while minimizing the distance between the mesh material 10 and the lumbar guide 32. . Therefore, even when the front and rear positions of the lumbar guide 32 are predetermined, the lumbar support device can be applied.

Further, in the present embodiment, the pad body 39 is a separate member from the frame 38, so the pad body 39 can be made of a material such as an elastomer that feels good against the body. Therefore, there is an advantage that the feeling of use can be further improved.

In this embodiment, when the body pressure of the seated person is not applied to the pad body 39, the locking projection 56 is disengaged from the locking groove 54, so that the engaging claw 47 is elastically deformed to adjust to an arbitrary height. is done with light force. Therefore, the pad body 39 can reliably prevent the pad body 39 from slipping (particularly from sliding down) due to the body pressure of the seated person without impairing the ease of height adjustment. If the center rib 55 is provided on the lifting body 41 as in the embodiment, the lock projection 56 can be accurately positioned, so there is an advantage that the locking operation can be ensured.

The upper end 32 a of the lumbar guide 32 can also be connected to the bearing boss 33 of the back support 8 . Various other structures can be adopted for both the height adjusting mechanism and the locking mechanism of the pad body 39 . As the height adjusting means, it is also possible to employ, for example, a ball catch structure in which a ball is biased by a spring instead of the engaging claw.

Furthermore, various forms can be adopted for the forms of the pad body and the lumbar guide as long as they have their functions. For example, the lumbar guide may be pipe-shaped or gutter-shaped (it is also possible to configure the lumbar guide body with two left and right members). Pad body 3
It is also possible to manufacture 9 and frame 38 in one piece.

(6). Outline of Second Embodiment Next, a second embodiment shown in FIG. 12 and subsequent drawings will be described. In this embodiment, codes are given independently from the first embodiment. First, an overview of the chair will be given. The chair comprises a leg device 1, a seat 2 and a backrest 3 as in the first embodiment.

As can be understood from FIGS. 14 and 15, a fixed base 5 is fixed to the upper end of the leg support 4, and a movable base 6 shown in FIG. It is connected so as to tilt backward about the center. As shown in FIG. 15(A), the movable base 6 is fixed with a seat bracket 6a.

A shell-shaped joint member 6b that also serves as a cover is fixed to the rear portion of the movable base 6, and left and right bosses formed at the lower end of the back support 7 are fitted into left and right recesses 6c formed in the rear portion of the joint member 6b. 8 is fitted from behind, and the lower end of the back support 7 and the joint member 6b are fixed with screws. The boss 8 of the back support 7 is fitted into the recess 6c so as not to tilt backward.

Note that the movable base 6 and the joint member 6b can be integrated, and both can be collectively called a tilting member. It is also possible to integrate the joint member 6b and the back support 7, in which case the joint member 6b can be called the lower end of the back support 7. As shown in FIG.

The back strut 7 has left and right vertically elongated members, which are connected at the upper end and the lower end. Therefore, the back brace 7 is formed in a frame shape that is open in the front and rear, and the interval between the left and right longitudinal members narrows upward.

The backrest 3 has a substantially rectangular back frame 9 with front and rear openings and a mesh material 10 stretched over the back frame 9. An upper member 11 of the back frame 9 is fixed to the upper end of the back support 7. there is The back frame 9 is composed of a main body portion that is open in the front and the rear and a cover member that overlaps the main body portion from the front, and the mesh material is attached to the cover member. Therefore,
The upper member 11 also has a double structure.

As shown in FIGS. 14(B) and 15(B), the upper end of the back support 7 is provided with a branch frame 12 to which the body portion of the upper member 11 of the back frame 9 is fixed. The cover member constituting the back frame 9 has a downward opening U-shaped portion in which the left and right side portions and the upper portion are integrally connected, and a lower cover overlapping the lower portion (lower member) 14 of the main body portion. there is

On the other hand, as shown in FIG. 15, for example, as an example of the lower support described in the claims, an upward strut frame 13 is fixed at the rear portion of the joint member 6b and at the middle portion between the left and right. , the lower part 14 of the main body of the back frame 9 is connected.

That is, as shown in FIG. 16B, a bearing portion 16 projecting forward is formed on the upper end of the support frame 13, and a keyhole-shaped cut-out groove 17 is formed in the bearing portion 16.
Left and right rearward bosses 14a are provided on the lower portion 14 of the body portion of the back frame 9, and oval pin portions 19 are provided on the left and right rearward bosses 14a. The pin portion 19 is attached to the back frame 9
When the back frame 9 is put in a different posture from the use state, it is fitted in the cut-out groove 17, and when the back frame 9 is returned to the use state, it does not come out of the cut-out groove 17. - 特許庁

Since the lower end of the back frame 9 is connected to the support frame 13 at the left and right intermediate portions, roughly speaking, the back frame 9 supports the back at three points, namely, two points on the left and right of the upper end and one point on the lower end. It is in a state of being connected to the strut 7 . Therefore, the backrest 3 can be easily deformed by the body pressure of the seated person so that the left and right sides recede backward.

Therefore, when the seated person twists the body in a reclining state or tilts to the left or right, the backrest 3 can change its planar shape or posture in accordance with the change in control of the body of the seated person. In other words, the backrest 3 changes its plan view posture without changing its overall shape, or changes its plan view shape by partially receding the left or right side.

(7). Basic Structure of Lumbar Support Device A lumbar support device 21 is attached to the strut frame 13 . This point will be explained below. As shown in FIG. 18, the lumbar support device 21 includes a lumbar guide 22 fixed to the post frame 13, an elevating body 23 attached to the lumbar guide 22 so as to be vertically movable, and an elevating body 23 attached via a cover 24. 17 and 19.
2, a pad body 27 is attached to the bearing member 25 via a horizontal pin (bolt) 26.
are connected so as to be vertically rotatable.

The lumbar guide 22, the lifting body 23, the cover 24, and the bearing member 25 constitute a supporting portion described in the claims. The upper end of the lumbar guide 22 is a free end, and the lifting body 23
is fitted into the lumbar guide 22 from above. Moreover, the pad body 27 and the bearing member 25 constitute a pad portion described in the claims. As shown in FIG. 17, the pad body 27 is loosely curved so as to be recessed forward in a plan view, and is gently curved so as to protrude forward in a side view.

As shown in FIG. 17 , left and right downward legs 28 are formed integrally with the lumbar guide 22 , while the left and right legs 28 of the lumbar guide 22 are inserted into the bearing portions 16 of the support frame 13 from above. , and as shown in FIG. 16, the receiving hole 29
A leg 28 penetrating through the support frame 13 is fixed to a boss portion 30 provided on the support frame 13 with a screw 31 .

The support frame 13 is made of resin, and a plurality of reinforcing ribs 32 are formed below the bearing portion 16, and the boss portion 30 is provided on the bottom surface of the longitudinal groove formed by the adjacent reinforcing ribs 32. .

The leg 28 has a horizontally long flat cross-section, and right and left first reinforcing legs 33 having a flat cross-section that is long in the front-rear direction project downward from the lower ends of the lumbar guides 22 in front of the left and right legs 28 . The first reinforcing leg 33 is inserted into a rectangular first engagement hole 34 formed in the bearing portion 16 of the support frame 13 . At the lower end of the first reinforcing leg 33, retaining claws 35 are formed inward so as to face each other.

Therefore, the first reinforcing leg 33 is inserted into the first engaging hole 34 against its elasticity,
When fully inserted, the retaining claw 35 is released from the engaging hole 34 to return to its original position, and is held so as not to come off upward. Since the first reinforcing leg 33 has a longitudinally long cross-sectional shape, it acts as a resistance to the backward tilting motion of the lumbar guide 22 when a backward force acts on the lumbar guide 22 due to the body pressure of a seated person.

As shown in FIGS. 17A and 17B, the upper end of the post frame 13 is an upwardly projecting portion 13a projecting above the bearing portion 16, and the lower end of the lumbar guide 22 is an upwardly projecting portion 13a. A receiving seat 36 is formed to be fitted in the stepped portion formed by the bearing portion 16 and the leg 28 and the first reinforcing leg 33 protrude downward from the receiving seat 36 .

Further, as shown in FIGS. 17A and 17B, the upwardly extending portion 13a of the support frame 13 is extended.
, a forward rib 38 having an arcuate shape in plan view is formed, and a receiving seat 36 of the lumbar guide 22 is formed with a recessed groove 39 that fits into the forward rib 38 . Note that the forward rib 38 may be formed over the entire length of the support frame 13 .

Further, as shown in FIGS. 17B and 17C, second reinforcing legs 40 positioned on the left and right outer sides of the left and right legs 28 project downward from the receiving seat 36 of the lumbar guide 22. , the upper end of the support frame 13 is provided with a second engaging hole 41 into which the second reinforcing leg 40 is fitted. Therefore, the lumbar guide 22 is supported by the support frame 13 by the left and right legs 28 and the left and right reinforcing legs 33 and 40 .
firmly attached to the

(8) Movable structure of the pad portion As shown in FIG. , in the lifting body 23,
A holding piece 45 that enters the dovetail groove 44 from the outside is integrally formed. The elevating body 23 is made of resin, and is integrally formed with a spring plate 46 protruding rearward. Engagement grooves 48 into which the engagement projections 47 are fitted and removed are formed in multiple stages on the front surface of the guide 22 .

Therefore, the lifting body 23 can move up and down by elastically deforming the spring plate 46.
A desired height is maintained by fitting the engaging projection 47 into one of the engaging grooves 48 .

As shown in FIG. 18, the cover 24 has a square shape when viewed from the front, and is fixed to the lifting body 23 by two screws 49 arranged at diagonal positions. A screw 49 passes through the lifting body 23 from behind and is screwed into a boss 50 formed on the cover 24 . As shown in FIG. 18(A),
The elevating body 23 and the cover 24 are held in a predetermined posture by fitting with positioning pins 23a and positioning holes 24a formed in the upper and lower portions.

The cover 24 has a laterally long rectangular through hole 51 through which the bearing member 25 protrudes forward. The bearing member 25 is attached to the flange 5 that contacts the rear surface of the cover 24 .
2. Therefore, it is held from the cover 24 so that it cannot be removed from the front.

As shown in FIGS. 18A and 20, the front surface of the cover 24 is formed with a rear rib 53 surrounding the flange 52 of the bearing member 25. As shown in FIG. There is a slight gap between the 24 and the rear facing rib 53 . A small gap also exists between the inner circumference of the through hole 51 and the outer circumference of the bearing member 25 .

The bearing member 25 has left and right support portions 54, and the rearward boss portions 55 provided on the pad body 27 and the left and right support portions 54 are, as described above, left and right longitudinal bolts as pins (support shafts). 26. The bolt 26 is held by a nut 57 so as not to come off.
As shown in FIG. 18(B), the nut 57 is fitted in a pocket hole 58 formed in one support portion 54 of the bearing member 25 so as to be non-rotatable and non-removable.

As shown in FIG. 18(B), the portion sandwiched between the left and right support portions 54 of the bearing member 25 has a
A recess 59 that opens forward is formed, and rubber (cellast) 60 as an example of an elastic body is fitted in this recess 59 . As shown in FIG. 19, the rubber 60 is
It is elastically stretched against the boss portion 55 of 7. Therefore, resistance due to friction of the rubber 60 is applied to the vertical rotation of the pad body 27 .

A rectangular tray-shaped spring bearing 61 is arranged between the lifting body 23 and the bearing member 25 . ) 62 intervening. The spring bearing 61 also constitutes a supporting portion described in the claims.
As shown in FIGS. 18A and 18B, the bearing member 25 is formed with a spring receiving hole 25a into which the end of the spring body 62 is inserted. A fitting spring receiving projection 63 is formed.

The outer periphery of the spring bearing 61 is formed by a flange 61 a , and a rear-facing portion surrounded by the flange 61 a is fitted into a rectangular hole 64 formed in the lifting body 23 . in this way,
Since the spring bearing 61 is partially fitted into the lifting body 23 from the front side, the front-to-rear width of the pad portion as a whole can be reduced to make it more compact.

As shown in FIGS. 16(A), 17(A), and 18, the upper end of the lumbar guide 22 is fitted with a substantially square stopper 66 in a front view that regulates the upward movement position of the elevator 23. As shown in FIGS. . Most of the stopper 66 is located on the left and right guide ribs 43 of the lumbar guide 22.
The left and right eaves pieces 66a overlap the upper surface of the lumbar guide 22 at the upper end.
is provided.

Then, the projections 68 protruding on the left and right outer sides of the stopper 66 are fitted into the recesses 69 provided on the inner surface of the guide ribs 43 of the lumbar guide 22, whereby the stopper 66 is
is held immovable up and down. Further, by fitting the downward protrusion 70 provided on the eaves piece 66a into the outward dovetail groove of the lumbar guide 22 from above, the front coming off is prevented. Therefore, the stopper 66 is attached to the lumbar guide 22 by deforming against its elasticity.

(9).Summary of Second Embodiment In this embodiment as well, as described above, when the seated person leans against the backrest 3 and twists his or her body or tilts left or right, the backrest 3 will move toward the user. However, since the lumbar guide 22 is attached to the support frame 13 independent of the back frame 9, the lumbar support changes in shape and posture of the backrest 3. The device does not interfere. Therefore, the fit of the backrest 2 to the body of the seated person can be improved.

In this embodiment, when the body pressure of the seated person is applied, the pad body 27 compresses the spring body 62 together with the bearing member 25 and retreats slightly. 20, the body is in a state of one-sided contact with the pad body 27, as indicated by white and black arrows in FIG.

Then, since there is a slight gap between the cover 24 and the bearing member 25,
As indicated by the dashed line in FIG. 20, the pad body 27 and the bearing member 25 are horizontally rotated (horizontally swung). As a result, the posture of the pad body 27 follows changes in the posture of the user's upper body, and a comfortable feeling of use can be obtained. Also in the present embodiment, the pad body 27 can rotate horizontally while retreating slightly, so that the cushioning property is excellent. Although FIG. 13 also shows the posture in which the pad body 27 is horizontally rotated, it is slightly exaggerated in FIG.

As shown in FIG. 19, in this embodiment, a slight gap 65 is provided between the mesh material 10 and the pad body 27 when the user's body pressure is not applied to the mesh material 10. . Therefore, the body pressure of the seated person acts on the pad body 27 after the mesh material 10 is slightly stretched and deformed. Therefore, it is possible to enjoy the cushioning property using the mesh material 10 and improve the comfort.

Further, when the height of the pad body 27 changes, the bending state of the mesh material 10 also changes. By changing the position of the vertex 27a of the pad body 27 following the change in posture of the material 10, the posture of the pad body 27 can follow the change in the bending state of the mesh material 10. - 特許庁Therefore, it is possible to further improve fit to the body.

Further, since the posture of the pad body 27 is lightly held by the rubber 60, the pad body 2
Even if there is a gap 65 between 7 and the mesh material 10, the pad body 27 does not fluctuate up and down. Therefore, it is possible to prevent the pad body 27 from excessively moving and giving a sense of discomfort to the person.

The height of the pad body 27 can be adjusted by pinching the elevating body 23 from the left and right and moving it upward or downward. Therefore, for example, as shown in FIG. 18, horizontal ribs 67 are formed in multiple stages on the left and right side surfaces of the lifting body 23 so as to improve the hooking of human fingers, and the upper end portion and the lower end portion of the lifting body 23 are oriented horizontally. It stands out a little. Since the upper end portion and the lower end portion of the lifting body 23 protrude in the horizontal direction, it is possible to prevent fingers from slipping. As a means for adjusting the height of the pad body 27, it is also possible to form left and right tabs on the rear surface of the pad body 27. FIG.

The lower portion (lower member) 14 of the back frame 9 can also be connected to the lower end portion of the back support 7 . That is, it is also possible to use the lower support as the back strut 7 . Even when the lower end of the back frame 9 is connected to the support frame 13 , it is possible to fix the lumbar guide 22 of the lumbar support device to the back support 7 . However, like this embodiment, the lumbar guide 22
is provided on the strut frame 13, there is an advantage that the structure can be simplified.

The present invention can be embodied in various ways other than the above embodiments. For example, as a support part,
It is not always necessary to provide a dedicated lumbar guide, and if the back support is provided as in the second embodiment, it is possible to attach the pad portion to the back support. Various structures can also be adopted for the pad portion. It is also possible to provide a plurality of pairs of spring bodies.

In the second embodiment, the pad body 27 rotates up and down with the upper and lower intermediate portions as the fulcrums, but it is also possible to shift the rotation fulcrums upward or downward.

The present invention can be embodied in a chair. Therefore, it can be used industrially.

[First embodiment]
2 backrest 9 back frame 10 mesh material 31 pad part constituting lumbar support device 32 lumbar guide constituting support part 38 frame constituting pad part 39 pad body constituting pad part 40 front member constituting pad part 41 support Elevating body constituting part [Second embodiment]
3 backrest 6b joint member 7 back support 9 back frame 13 support frame as an example of a lower support 14 lower part of back frame (lower member)
21 lumbar support device 22 lumbar guide that constitutes the support portion 23 elevator that constitutes the support portion 24 cover that constitutes the support portion 25 bearing member that constitutes the support portion 26 bolt (pin)
27 Pad body 28 Foot body 46 Spring plate 47 Engagement protrusion 48 Engagement groove 60 Rubber (elastic body)
61 Spring retainer constituting support portion 62 Spring body 65 Gap between pad body and mesh material

The lumbar pad device of the present invention is specified in each claim. Of these, the invention of claim 1 is
" A seat arranged above a leg device equipped with casters, a backrest tilting backward against elasticity, and a lumbar support device arranged behind the backrest in a state independent of the backrest. cage,
The backrest is a chair in which a back frame that is open forward and backward is provided with a flexibly deformable back support member,
When the seated person's body pressure is applied unevenly in the left-right direction, the back frame can change its shape or posture in plan view against elasticity .
The lumbar support device has a laterally elongated pad section on which body pressure of a seated person is applied via the back support material, and a support section to which the pad section is attached so as to be movable back and forth ,
The support portion is arranged to be movable relative to the back frame,
The pad section is horizontally rotatably supported by the support section via left and right spring bodies that deform independently of each other ,
When the body pressure of the seated person is unevenly applied to the backrest in the horizontal direction, the plan view shape or posture of the back frame may change, and the pad portion may also change depending on the posture change or shape change of the back frame. It can be rotated horizontally to follow. ”
It is configured.

The invention of claim 2 is
" A backrest comprising a back frame with a front and rear opening and a flexible and deformable backrest member, and a lumbar support device arranged behind the backrest member independently of the backrest,
The backrest may change its shape or posture in plan view when the body pressure of the seated person is applied unevenly in the left-right direction.
The lumbar support device has a laterally elongated pad section on which the body pressure of a seated person is applied via the backrest material, and a support section to which the pad section is attached so as to be movable back and forth. , the pad portion is arranged to be movable relative to the back frame, and the pad portion is supported by the support portion via left and right spring bodies so that the posture in a plan view changes following a change in shape or posture of the backrest. A supported chair ,
The support part of the lumbar support device includes a vertically elongated lumbar guide, the upper end of the lumbar guide is connected to the back support to which the back frame is attached, and the lower end of the lumbar guide is connected to the back frame. While connected to the left and right intermediate parts of the lower part of
The pad portion includes a left and right long frame body that protrudes greatly to the left and right outer sides of the left and right spring bodies in a state of covering the lumbar guide from behind, and a front member attached to the frame body in a state of covering the lumbar guide from the front. and a pad body that spans the left and right ends of the frame body,
Between the hollow portion composed of the frame body and the front member and the lumbar guide, a gap is formed to allow the frame body and the front member to rotate horizontally."
It is configured. In the present application, "connection" includes both a relatively movable state and a fixed state.

In addition, the invention of claim 3 is, in claim 1,
"The back frame is allowed to change its posture following changes in the posture of a seated person by connecting the left and right intermediate portions of its lower end to the lower support,
The support portion of the lumbar support device includes a vertically elongated lumbar guide provided on the lower support body and having a free upper end, and an elevating body attached to the lumbar guide so as to be able to move up and down. , and the pad portion, which is long in the left and right direction, is attached to the elevating body so as to be horizontally rotatable.”
It is configured. Note that "posture change" includes deformation.

The structure for horizontally rotating the pad portion can be embodied in various ways, but in claim 2, since the lumbar guide is surrounded by the hollow portion made up of the frame and the front member, there is an advantage that the number of members can be reduced and the size can be reduced. There is According to claim 2, the upper end of the lumbar guide is connected to the back support and the lower end of the lumbar guide is connected to the lower left and right intermediate portions of the back frame. The torsional deformation of the back frame in a plan view can be allowed without changing the front-rear position. As a result, it is ensured that the posture of the pad body follows the posture change of the body.

Also in the configuration of claim 3, since the lower end of the back frame is connected to the lower support member at its left and right middle portions, the back frame can be deformed or changed in posture following changes in the body posture of the seated person. is allowed. Furthermore, since the lumbar guide of the lumbar support device is also provided on the lower support, the distance between the lumbar guide and the backrest is kept constant, and the body support function of the pad body can be ensured. That is, it is possible to secure an accurate lumbar support function while allowing the backrest to twist.

The backrest 2 comprises a back frame 9 and a mesh material 10. - 特許庁An edge member such as a resin tape is fixed to the outer peripheral edge of the mesh material 10 by means of fitting or the like, and the edge member is attached to the back frame 9 .

(2).Overview of Lumbar Support Device The backrest 2 is provided with a lumbar support device. The lumbar support device has a pad portion 31 that supports a seated person from behind through a mesh material 10, and a lumbar guide body (lumbar support) 32 to which the pad portion 31 is attached so as to be adjustable in height. The upper end of the guide body 32 is connected to the connecting portion between the middle member 14 and the back support 8 , and the lower end of the lumbar guide body 32 is connected to the lower member 13 . Also, the lumbar guide body 32 has a strip-like shape, and is gently curved as a whole so as to protrude forward in a side view.

When the backrest 2 tilts backward about the second shaft 15, the lower end of the back frame 9 tries to rotate forward, but the lower end of the back frame 9 is restricted by the third shaft 19 so that it cannot move forward. Therefore, the chevron portion of the back frame 9 tends to spread outward and deform. Further, when the backrest 2 tilts backward, the lumbar guide body 32 deforms so as to increase the degree of bending, as indicated by the black arrow in FIG. 1(B). As a result, the pad portion 31 tends to move forward, and the waist of the seated person is firmly supported.

An upper end portion 32 a of the lumbar guide 32 is connected to a lower end portion of the middle member 14 . That is, as shown in FIG. 6A, for example, a bearing recess 34 is formed at the lower end of the middle member 14 so as to open downward and rearward, into which the bearing boss 33 provided at the upper end of the back column 8 fits. An engagement pin (not shown) provided in the upper portion of the bearing recess 34 is fitted into an engagement hole 32c shown in FIG. It is held by the stopped stopper member 35 so as not to come off .

In this embodiment, the left and right side members 11 of the back frame 9 are configured to be elastically deformed by the body pressure of the seated person and to rotate backward around the lower ends connected by the pins 22. . Therefore, when the seated person twists the upper body to the left or right, or tilts the upper body to the left or right, it can easily deform to follow the posture change of the seated person. Since the pad body 39 horizontally rotates following the deformation of the back frame 9 , the seated person does not feel the tension caused by the left or right end of the pad body 39 . For this reason, it is excellent in usability and comfortable.

Therefore, when the seated person twists the body in a reclining state or tilts to the left or right, the backrest 3 can change its planar shape or posture to follow the change in body posture of the seated person. In other words, the backrest 3 changes its plan view posture without changing its overall shape, or changes its plan view shape by partially receding the left or right side.

A rectangular tray-shaped spring bearing 61 is arranged between the lifting body 23 and the bearing member 25 . ) 62 intervening. The spring bearing 61 also constitutes a supporting portion described in the claims. As shown in FIGS. 18A and 18B, the bearing member 25 is formed with a spring receiving hole 25a into which the end of the spring body 62 is inserted. A round spring receiving projection 63 is formed.

The height of the pad body 27 can be adjusted by pinching the elevating body 23 from the left and right and moving it upward or downward. Therefore, for example, as shown in FIG. 18, horizontal ribs 67 are formed in multiple stages on the left and right side surfaces of the lifting body 23 so that the fingers can be easily caught, and the upper end and the lower end of the lifting body 23 are oriented horizontally. is made to protrude a little. Since the upper end portion and the lower end portion of the lifting body 23 protrude in the horizontal direction, it is possible to prevent fingers from slipping. As a means for adjusting the height of the pad body 27, it is also possible to form left and right tabs on the rear surface of the pad body 27. FIG.

Claims (6)

The backrest is provided with a flexible and deformable backrest member on a back frame that opens forward and backward, and a lumbar support device is arranged behind the backrest member independently from the backrest,
The backrest may change its shape or posture in plan view when the body pressure of the seated person is applied unevenly in the left-right direction.
The lumbar support device has a laterally elongated pad section on which the body pressure of a seated person is applied via the backrest material, and a support section to which the pad section is attached so as to be movable back and forth. , the pad portion is arranged to be movable relative to the back frame, and the pad portion is supported by the support portion via left and right spring bodies so that the posture in a plan view changes following a change in shape or posture of the backrest. supported,
A chair with lumbar support. The support part includes a vertically elongated lumbar guide, the upper end of the lumbar guide is connected to the back support to which the back frame is attached, and the lower end of the lumbar is located between the left and right of the lower part of the back frame. While connected to the department,
The pad portion includes a left and right long frame body that protrudes greatly to the left and right outer sides of the left and right spring bodies in a state of covering the lumbar guide from behind, and a front member attached to the frame body in a state of covering the lumbar guide from the front. and a pad body that spans the left and right ends of the frame body,
Between the hollow portion formed by the frame body and the front member and the lumbar guide,
forming a gap that allows the frame body and the front member to rotate horizontally;
A chair with a lumbar support device according to claim 1. The back frame is allowed to change its posture following changes in the posture of a seated person by connecting the left and right intermediate portions of the lower end portion thereof to the lower support member.
The support portion of the lumbar support device includes a vertically elongated lumbar guide provided on the lower support body and having a free upper end, and an elevating body attached to the lumbar guide so as to be able to move up and down. , the vertically long pad portion that protrudes greatly on both left and right sides of the lumbar guide is attached to the lifting body so as to be horizontally rotatable;
A chair with a lumbar support device according to claim 1. The pad section has a pad body that rotates up and down around a horizontal axis,
A chair with a lumbar support device according to any one of claims 1 to 3. comprising an elastic body that imparts resistance to vertical rotation of the pad body;
A chair with a lumbar support device according to claim 4. A gap is set between the pad portion and the back support material in an initial state where the rearward body pressure of the seated person is not applied to the backrest.
A chair with a lumbar support device according to any one of claims 1 to 5.

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