JP6920156B2 - Chair - Google Patents

Description

The present invention relates to a chair.

In recent years, diversification of work attitudes has been proposed for the purpose of improving health and improving work efficiency in office work. Examples of the working posture include a basic posture in which the seated person sits deeply on the chair, and a semi-standing posture in which the seated person sits shallowly on the chair with the knees bent slightly at a position higher than the basic posture. ..

Some conventional chairs are equipped with a gas spring as a mechanism for adjusting the height of the seating surface. However, it is difficult to secure the stroke from the seating surface in the basic posture to the seating surface in the semi-standing posture with only the gas spring.

Here, Patent Document 1 below discloses a chair in which the height of the seating surface can be switched by configuring the seat to be rotatable. Specifically, in Patent Document 1 below, a seat assembly (seat) is rotatably supported by a back assembly (backrest) fixed to a pedestal (support structure) via a pivot rod. The seat assembly includes a seat surface and a flange extending downward from the front edge of the seat surface.

According to this configuration, the seat surface can be the first seating surface when the seat surface faces upward. In this case, it is considered that the seated person can support the portion from the buttocks to the thighs of the seated person by the seating surface by sitting deeply (the above-mentioned basic posture).
On the other hand, when the seat assembly is rotated upward around the pivot rod, the flange faces upward, and the flange portion rises by the length in the depth direction of the seat surface from the seat surface height in the basic posture. As a result, the flange can be used as the second seating surface, and it is considered that the buttocks of the seated person can be supported by the flange in a state where the seated person sits shallowly (the above-mentioned semi-standing posture).

U.S. Patent Application Publication No. 2015/0282623

By the way, the chair may be equipped with a mechanism (synchro mechanism) in which the seat moves in the depth direction following the tilt of the backrest for the purpose of improving comfort and the like.
However, in the configuration of Patent Document 1 described above, since the back assembly is fixed to the pedestal, there is still room for improvement in terms of improving comfort and responding to diversification of working postures.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a chair capable of responding to diversification of working postures while improving comfort.

In order to achieve the above object, the chair according to one aspect of the present invention includes a support structure, a backrest rotatably supported by the support structure around the first axis along the width direction, and the support. It is rotatable between the first seating position, which is arranged above the structure and constitutes the first seating surface, and the second seating position, which constitutes the second seating surface located above the first seating surface. The seat supported by the backrest and the seat supported by the support structure and located at least in the first seating position are supported, and the seat is moved from the first seating position to the second seating position. The seat is supported by the seat support member at the first seating position between the seat and the seat support member, and the seat is supported by the seat support member. A variable support portion that allows the seat to move in the depth direction as it rotates around one axis is provided, and the seat is located on the depth side in the depth direction and around the second axis along the width direction. The first seat body rotatably supported by the backrest and the first seat body are located on the front side in the depth direction and can rotate around the third axis along the width direction. Has a second seat body supported by the first seat body, and at the first seating position, the seating surface of the first seating body and the seating surface of the second seating body are connected to each other for the first seating. The first seat body is arranged so as to extend upward from the second axis at the second seating position, and the second seat body is located above the first seat body. The seating surface of the two seating bodies constitutes the second seating surface .
According to this configuration, the seat can be supported in both the basic posture and the semi-standing posture by changing the seat to the first seating position and the second seating position.
In particular, according to this aspect, since the seat is supported by the backrest, the seat tends to move around the first axis in response to the rotation of the backrest around the first axis. At this time, since the seat is allowed to move in the depth direction by the variable support portion, the seat moves in the depth direction following the rotational movement of the backrest.
As a result, it is possible to cope with the diversification of working postures while improving the comfort.

Further , in the first seating position, since the seating surfaces of the first and second seating bodies are integrated to form the first seating surface, the portion from the buttocks to the thighs of the seated person is stably supported. can do.
On the other hand, in the second seating position, the seating height of the second seating body is determined by the depth length of the first seating body. The seat height can be lowered. As a result, in the second position, the buttocks of the seated person can be stably supported with the knees slightly bent. Therefore, an appropriate sitting posture can be obtained at both the first position and the second position.
Further, since the seat height at the second seating position can be adjusted by the depth length of the first seat, the degree of freedom in design and design can be improved.

In the chair according to one aspect of the present invention, the seating surface of the second seat may be provided with an inclined portion that inclines downward toward the front end edge in the depth direction.
According to this configuration, in the first seating position, the portion of the thigh near the knee is supported by the inclined portion. As a result, it is possible to suppress the pressure on the portion of the thigh near the knee as compared with the case where the seat surface of the second seat is formed on a flat surface.
On the other hand, in the second seating position, the portion of the thigh near the buttocks is supported by the inclined portion. As a result, it is possible to suppress the pressure on the portion of the thigh near the buttocks as compared with the case where the seating surface of the second seat is formed on a flat surface. In this way, the thighs of the seated person are suppressed from being pressed by the inclined portion at both the first seating position and the second seating position.

In the chair according to one aspect of the present invention, the backrest includes a load supporting surface that supports the load of the seated person, and a grip portion that is separated from the load supporting surface toward the back side in the depth direction. You may.
According to this configuration, the chair can be easily carried to a desired place by gripping the grip portion and moving the chair. As a result, it is possible to perform work or the like in a desired sitting posture regardless of the location (for example, even in a location other than one's own seat).

The chair according to one aspect of the present invention is arranged above the support structure, a backrest rotatably supported by the support structure around the first axis along the width direction, and the support structure. It is rotatably supported by the backrest between the first seating position constituting the first seating surface and the second seating position constituting the second seating surface located above the first seating surface. A seat, a seat support member supported by the support structure, supporting the seat located at least in the first seating position, and allowing the seat to move from the first seating position to the second seating position. With the seat supported by the seat support member at the first seating position between the seat and the seat support member, the backrest is rotated around the first axis. A variable support portion that allows movement of the seat in the depth direction is provided, and the seat support member is a first end portion that is rotatably connected to the support structure around a fourth axis along the width direction. And a second end portion that is located on the front side in the depth direction with respect to the fourth axis and is rotatably connected to the seat around the fifth axis along the width direction. The variable support portion may allow the displacement of the fifth axis in the direction of approaching and separating from the first axis as the seat moves between the first seating position and the second seating position.
According to this configuration, the seat support member can be made to follow the movement of the seat between the first seating position and the second seating position, so that the seat can always be stably supported by the seat support member.

According to one aspect of the present invention, it is possible to cope with the diversification of working postures while improving the comfort.

It is a perspective view which looked at the chair which concerns on embodiment from the left front direction. It is a perspective view which looked at the chair which concerns on embodiment from below. It is a side view which looked at the chair which concerns on embodiment from the left side. It is sectional drawing corresponding to the IV-IV line of FIG. It is a side view of the chair corresponding to FIG. 3 which shows the state which the seat is in a semi-standing position. It is explanatory drawing of the reclining operation, and is the side view of the chair corresponding to FIG. It is explanatory drawing for demonstrating the method of switching the seat surface height, and is the side view of the chair corresponding to FIG. It is a side view which looked at the chair which concerns on 2nd Embodiment from the left side. It is explanatory drawing of the reclining operation, and is the side view of the chair corresponding to FIG. It is a side view of the chair corresponding to FIG. 8 which shows the state which the seat is in a semi-standing position. It is a schematic side view of the chair which concerns on 3rd Embodiment. It is explanatory drawing of the reclining operation, and is the schematic side view of the chair corresponding to FIG. It is a perspective view which looked at the chair which concerns on 4th Embodiment from the left front. It is a side view of the chair which concerns on 4th Embodiment. It is a side view of the chair corresponding to FIG. 14 which shows the state which the seat is in a semi-standing position. It is a top view of the chair which concerns on 4th Embodiment. It is an enlarged sectional view of the seat which concerns on the modification of 4th Embodiment. It is an enlarged sectional view of the seat which concerns on the modification of 4th Embodiment.

Next, an embodiment of the present invention will be described with reference to the drawings. In the following description, the orientations such as front-back, up-down, left-right, etc. are the same as the orientations of the person (seat person) seated in the chair 1 in the normal posture. In this case, the front-rear direction corresponds to the depth direction of the present invention, and the left-right direction corresponds to the width direction of the present invention. Further, in the figure, the arrow UP indicates the upper side, the arrow FR indicates the front side, and the LH indicates the left side.

(First Embodiment)
[Chair]
FIG. 1 is a perspective view of the chair 1 as viewed from the front left direction.
As shown in FIG. 1, the chair 1 includes a leg 2, a support base 3, a seat 4, a backrest 5, and an armrest 6.

The leg 2 includes a multi-leg 7 and a pedestal 8 erected from the center of the multi-leg 7.
Casters 9 capable of traveling on the floor are attached to each leg of the multi-leg 7.
The pedestal 8 has a built-in gas spring (not shown) which is an elevating mechanism for elevating and lowering the rod 10. That is, when the rod 10 is raised and lowered by the gas spring, the seat 4, the backrest 5, and the armrest 6 are raised and lowered integrally.

The support base 3 is connected to the upper end portion of the pedestal 8 (rod 10).
The seat 4 is supported from below by the support base 3. The seat 4 supports the buttocks and the like of the seated person from below.
The backrest 5 is tiltably connected to the support base 3 behind the seat 4. The backrest 5 supports the waist and back of the seated person from behind.
The armrests 6 are fixed to the backrests 5 on both the left and right sides of the seat 4. The armrest 6 supports the seated person's arm or the like from below.

<Support>
FIG. 2 is a perspective view of the chair 1 as viewed from below.
As shown in FIG. 2, the support base 3 mainly includes a support basic body 21 and a link arm 23. The support base 3 is also equipped with an operation unit (not shown) for operating the elevating mechanism described above.

The support basic body 21 functions as a strength member in supporting the load of the seated person. The support basic body 21 includes a base portion 25 and a base arm 26.
The base portion 25 is fixed to the upper end portion of the rod 10.
The base arm 26 extends rearward from both ends in the left-right direction of the base portion 25.

<Back lean>
FIG. 3 is a side view of the chair 1 as viewed from the left side.
As shown in FIGS. 1 and 3, the above-mentioned backrest 5 includes a backrest frame 31, a tension member 32 provided on the backrest frame 31, and an extension portion 33 extending from the backrest frame 31. , A torsion unit 34 for connecting the extension portion 33 and the support base 3 is mainly provided.
The backrest frame 31 is formed in a rectangular frame shape when viewed from the front. The backrest frame 31 functions as a strength member in supporting the load of the seated person. Specifically, the backrest frame 31 has a pair of side frames 31a that are located on both the left and right sides and extend in the vertical direction, and a connecting frame 31b that connects the upper ends of the side frames 31a.

The connecting frame 31b has a connecting portion 31c extending rearward from the upper end portion of each side frame 31a, and a horizontal portion 31d connecting the rear end portions of the connecting portions 31c to each other.
The horizontal portion 31d has a curved shape that is convex toward the rear in a plan view seen from the vertical direction.

The upholstery member 32 covers the opening of the backrest frame 31 from the front by being erected between the above-mentioned side frames 31a. The front surface of the upholstery member 32 functions as a load supporting surface that supports the load from the back when the seated person is seated.
The connecting frame 31b described above projects upward from the upholstery member 32. The horizontal portion 31d of the connecting frame 31b is separated rearward from the upholstery member 32. The horizontal portion 31d functions as a grip portion that can be gripped with a hand or the like inserted into the space defined by the upper end edge of the upholstery member 32 and the connecting frame 31b. That is, the seated person can easily carry the chair 1 to a desired place by grasping the horizontal portion 31d and moving the chair 1. As a result, it is possible to perform work or the like in a desired sitting posture regardless of the location (for example, even in a location other than one's own seat).

As shown in FIG. 3, the extension portion 33 is connected to the lower frame portion of the backrest frame 31. Specifically, the extension portion 33 extends forward toward the bottom. The extension portion 33 is provided with a backrest bracket 35. The backrest bracket 35 may be provided integrally with the extension portion 33. In the present embodiment, the support structure is composed of the support basic body 21 described above.

The backrest bracket 35 is formed with a seat support portion 36 and a damper support portion 37 that project upward from the extension portion 33. In the present embodiment, the seat support portion 36 is located above and behind the damper support portion 37. However, the relative positions of the seat support portion 36 and the damper support portion 37 can be changed as appropriate.

As shown in FIG. 2, the torsion unit 34 is housed in a portion of the support basic body 21 located between the base arms 26. The torsion unit 34 is interposed between the support basic body 21 and the extension portion 33 to elastically support the tilt of the backrest 5.

FIG. 4 is a cross-sectional view corresponding to line IV-IV of FIG.
As shown in FIG. 4, the torsion unit 34 mainly includes a pivot 41, a rubber torsion 42 (elastic member), and a housing 43.

The pivot 41 is formed in a prismatic shape extending in the left-right direction. Both ends of the pivot 41 in the left-right direction are non-rotatably supported by the base arm 26.
The rubber torsion 42 is formed in a tubular shape that surrounds the circumference of the pivot 41. The inner peripheral surface of the rubber torsion 42 is fixed to the outer peripheral surface of the pivot 41.
The housing 43 is formed in a tubular shape that surrounds the rubber torsion 42. The inner peripheral surface of the housing 43 is fixed to the outer peripheral surface of the rubber torsion 42. An extension 33 (see FIG. 2) is connected to the rear end of the housing 43. A rotation restricting member (not shown) that defines the rotation range of the housing 43 is provided between the housing 43 and the support basic body 21. The reclining mechanism of the backrest 5 is not limited to the torsion unit 34.

As shown in FIG. 2, the link arms 23 are arranged in pairs with respect to the support basic body 21 (base arm 26) described above on the outside in the left-right direction (direction away from the center in the left-right direction). The rear end of each link arm 23 is connected to the corresponding base arm 26 via an arm rotation shaft 51. The arm rotation shafts 51 extend in the left-right direction, respectively. That is, the rear end portion of the link arm 23 is rotatably supported by the base arm 26 around the axis line Oa (see FIG. 3) along the left-right direction. In the illustrated example, the pair of link arms 23 are connected to each other by a bridge portion 52 at the central portion in the front-rear direction.

As shown in FIG. 3, a guide portion 55 is formed at the front end portion of each link arm 23. The guide portion 55 is formed in an elongated hole that penetrates each link arm 23 in the left-right direction and extends in the extending direction (front-back direction in the illustrated example) of the link arm 23.

<Za>
The seat 4 is divided into a rear seat body 61 located at the rear and a front seat body 62 located at the front of the rear seat body 61.
The rear seat body 61 includes a rear main body portion 63, a backrest connecting portion 64, and a rear seat body connecting portion 65.
The rear main body 63 is configured by attaching a cushioning material or a tensioning material to a substrate forming a skeleton.

The backrest connecting portion 64 projects downward at the rear portion of the rear main body portion 63. The backrest connecting portion 64 is connected to the seat support portion 36 of the backrest bracket 35 described above via a rear rotation shaft 66 extending in the left-right direction. That is, the rear seat body 61 is supported by the backrest bracket 35 so as to be rotatable around the axis Ob along the left-right direction.

The rear seat body connecting portion 65 is provided on the lower surface of the rear main body portion 63 in a state of protruding forward from the front end edge of the rear main body portion 63. In the illustrated example, a plurality (for example, three) of the rear seat body connecting portions 65 are provided at intervals in the left-right direction. The design of the positions and numbers of the rear seat connecting portions 65 can be changed as appropriate.

The front seat body 62 mainly includes a front main body portion 71, a front seat body connecting portion 72, and an arm connecting portion 73.
Similar to the rear main body 63, the front main body 71 is configured by attaching a cushioning material or a tensioning material to a substrate forming a skeleton. In the present embodiment, the length of the front main body 71 in the front-rear direction is shorter than the length of the rear main body 63 in the front-rear direction. However, the length of the front main body 71 may be shorter than that of the rear main body 63 or equal to that of the rear main body 63. The front portion of the front main body 71 of the present embodiment forms an inclined portion 71a that inclines downward toward the front end edge of the front main body 71. The inclined portion 71a may be formed at least in the front portion of the front main body portion 71, and the entire front main body portion 71 may be formed as the inclined portion 71a.

The front seat body connecting portion 72 is provided on the lower surface of the front main body portion 71 in a state of protruding rearward from the rear end edge of the front main body portion 71. A plurality (for example, three) of front side seat connecting portions 72 are provided at intervals in the left-right direction corresponding to the rear side seat connecting portion 65. Each front seat connecting portion 72 is supported by a rear seat connecting portion 65 corresponding to each other in the left-right direction via a seat connecting pin 75. Each seat connecting pin 75 extends in the left-right direction in front of the above-mentioned rear rotation shaft 66. That is, the front side seat body 62 is rotatably connected to the rear side seat body 61 around the axis line Occ along the left-right direction.

In the present embodiment, the configuration in which the posterior seat body 61 and the front seat body 62 are divided has been described, but the present invention is not limited to this configuration, and the posterior seat body 61 and the front seat body 62 are rotatably supported. It doesn't matter if it is done. In this case, for example, the seat 4 may be bendable between the posterior seat body 61 and the front seat body 62.

The arm connecting portion 73 projects downward from a portion located in front of the front seat connecting portion 72 on the lower surface of the front main body portion 71. A pair of arm connecting portions 73 are provided at intervals in the left-right direction corresponding to the link arm 23 described above. Each arm connecting portion 73 is connected to the front end portion of the corresponding link arm 23 via a front rotating shaft 76 extending in the left-right direction. Specifically, the front rotation shaft 76 is connected to the arm connecting portion 73 through the guide portion 55 of the link arm 23. In this case, the front seat body 62 is rotatably supported by the link arm 23 around the axis Od along the left-right direction. The front rotation shaft 76 is configured to be movable with respect to the link arm 23 along the extending direction (front-rear direction) of the link arm 23 of the front seat body 62.

As described above, the chair 1 of the present embodiment includes the rear seat body 61 and the backrest bracket 35, the rear seat body 61 and the front seat body 62, the link arm 23 and the support basic body 21, and the link arm 23. And between the front seat bodies 62 are rotatably connected around the axes Oa to Od along the left-right direction, respectively. That is, in the chair 1 of the present embodiment, the backrest bracket 35 is a fixed link, the rear seat body 61, the front seat body 62, and the link arm 23 are movable links, and the links are rotatably connected to each other. It also constitutes a so-called four-section link mechanism.

FIG. 5 is a side view of the chair 1 showing a state in which the seat 4 is in a semi-standing position.
As shown in FIGS. 3 and 5, the seat 4 of the present embodiment can be switched between a basic position (see FIG. 3) and a semi-standing position (see FIG. 5) in which the seating position is higher than the basic position. It is configured. Specifically, at the basic position shown in FIG. 3, the posterior seat 61 and the front seat 62 are aligned in the front-rear direction at the same height, and the seat surfaces (upper surface) of the posterior seat 61 and the front seat 62 are aligned. They are arranged flush with each other. That is, both the seating surfaces of the posterior seat body 61 and the front seat body 62 function as seating surfaces at the basic positions. In the basic position, with the seated person sitting deeply on the seat 4, the portion from the buttocks to the thighs of the seated person is supported by the seating surfaces of the posterior seat body 61 and the front seat body 62. At this time, the portion of the thigh near the knee is supported by the anterior seat body 62 (anterior main body portion 71) by the inclined portion 71a. As a result, it is possible to suppress the compression of the portion of the thigh near the knee as compared with the case where the seat surface of the front seat body 62 is formed on a flat surface.

On the other hand, in the semi-standing position shown in FIG. 5, the rear seat body 61 and the link arm 23 extend diagonally upward from the axes Oa and Ob, respectively, and the seat surface of the front seat body 62 faces upward. It is held above the side seat 61 and the link arm 23. That is, the seating surface of the front seating body 62 functions as a seating surface in the semi-standing position. In the semi-standing position, with the knees slightly bent, the buttocks and the portion of the thighs closer to the buttocks are supported by the seating surface of the anterior seat body 62. At this time, the portion of the thigh near the buttocks is supported by the inclined portion 71a on the front side seat body 62 (front side main body portion 71). As a result, it is possible to suppress the compression of the portion of the thigh near the buttocks as compared with the case where the seat surface of the front seat body 62 is formed on a flat surface. In this way, the thighs of the seated person are suppressed from being pressed by the inclined portion 71a in both the basic position and the semi-standing position. The seating surface of the front seat body 62 in the semi-standing position may be tilted (for example, forward tilted) with respect to the horizontal direction.

In the present embodiment, the seat height at the basic position of the elevating mechanism (gas spring) at the uppermost position is lower than the seat height at the semi-standing position at the lowermost position of the elevating mechanism. However, the seat height at the basic position at the uppermost position of the elevating mechanism (gas spring) may be set to be equal to or higher than the seat height at the semi-standing position at the lowermost position of the elevating mechanism. In the semi-standing position, the seat height of the front seat body 62 can be adjusted by operating the elevating mechanism (gas spring) by an operation mechanism (not shown). This point is the same in each of the following embodiments.

As shown in FIGS. 2 and 3, of the above-mentioned posterior seat connecting portions 65 and the front seat connecting portions 72, the posterior seat connecting portion 65a and the front seat connecting portion 65a located in the central portion in the left-right direction. A gas damper 80 is connected between the seat connecting pin 75a that connects the connecting portions 72a to each other and the damper support portion 37. The gas damper 80 is configured so that the rod 82 can move forward and backward with respect to the cylinder 81.

As shown in FIG. 3, the gas damper 80 is rotatably connected to the damper support portion 37 via a damper connecting pin 85 whose rear end portion of the cylinder 81 extends in the left-right direction. On the other hand, in the gas damper 80, the front end portion of the rod 82 is rotatably connected to the seat body connecting pin 75a. That is, the gas damper 80 rotates around the damper connecting pin 85 and the seat connecting pin 75 according to the switching operation between the basic position and the semi-standing position of the seat 4, and the rod 82 advances and retreats with respect to the cylinder 81. .. The configuration may not have the gas damper 80.

Of the link arm 23 and each base arm 26, a regulation mechanism 90 for holding the seat 4 in either the basic position or the semi-standing position is provided between the link arm 23 and the base arm 26 facing each other in the left-right direction. ing. The regulating mechanism 90 engages the through hole 91 formed in the link arm 23, the first engaging recess 92 and the second engaging recess 93 formed in the base arm 26, and the link arm 23 and the base arm 26. It includes an engaging pin 95.

The through hole 91 penetrates the link arm 23 in the left-right direction.
The engaging recesses 92 and 93 are opened outward in the left-right direction in the base arm 26. The engaging recesses 92 and 93 are formed at intervals on the movement locus of the through hole 91 accompanying the rotation of the link arm 23. Specifically, the first engaging recess 92 is formed at a position where it overlaps with the through hole 91 at the basic position when viewed from the left and right directions. As shown in FIG. 5, the second engaging recess 93 is formed at a position where it overlaps with the through hole 91 in a semi-standing position when viewed from the left and right.

The engaging pin 95 is configured to be able to enter either the first engaging recess 92 or the second engaging recess 93 through the through hole 91. Specifically, the engaging pin 95 is configured to be able to enter the first engaging recess 92 through the through hole 91 at the basic position. As a result, the rotational operation of the link arm 23 with respect to the base arm 26 is restricted.
The engaging pin 95 is configured to be able to enter the second engaging recess 93 through the through hole 91 in the semi-standing position. As a result, the rotational operation of the link arm 23 with respect to the base arm 26 is restricted. The engaging pin 95 may be slidably supported by, for example, the link arm 23, or may be provided separately from the link arm 23 and the base arm 26.

[Action]
<Reclining operation>
Next, as the action of the chair 1 described above, the reclining operation will be described first. FIG. 6 is an explanatory view of the reclining operation, and is a side view corresponding to FIG. In the following description, the reclining operation at the basic position of the seat 4 will be described. In the following description, the state shown in FIG. 3 (the state in which the backrest 5 is most raised) is set as the initial position.
As shown in FIGS. 3 and 6, when the seated person leans against the backrest 5, the backrest 5 rotates backward around the pivot 41 together with the housing 43 of the torsion unit 34 according to the load acting on the backrest 5. do. When the housing 43 rotates with respect to the pivot 41, the rubber torsion 42 twists. As a result, the backrest 5 tilts backward (backward tilt position) in a state where the restoring force of the rubber torsion 42 is applied via the housing 43.
On the other hand, when the seated person separates from the backrest 5, the backrest 5 rotates forward together with the housing 43 around the pivot 41 due to the restoring force of the rubber torsion 42. As a result, the backrest 5 rises from the backward tilted position to the initial position.

Here, of the seats 4, the rear seat body 61 is connected to the backrest bracket 35 via the rear rotation shaft 66. Therefore, for example, when the backrest 5 tilts backward from the initial position, the seat 4 is pulled backward along with the rearward displacement of the backrest 5. At this time, the front rotation shaft 76 moves rearward (in the direction approaching the pivot 41) in the guide portion 55, so that the seat 4 moves rearward so as to follow the tilt of the backrest 5. The front rotation shaft 76 does not come into contact with the first end edge (rear end edge in FIG. 3) of the inner peripheral edge of the guide portion 55 even when the backrest 5 moves to the rearmost tilted position. It is set.

On the other hand, when the backrest 5 returns from the backward tilted position to the initial position, the seat 4 is pushed forward following the forward tilt of the backrest 5 around the pivot 41. At this time, the front rotation shaft 76 moves forward in the guide portion 55 (in the direction away from the pivot 41), so that the seat 4 moves forward so as to follow the tilt of the backrest 5. The front rotation shaft 76 approaches the second end edge (front end edge in FIG. 3) of the guide portion 55 when the backrest 5 moves to the most forward tilted position.

In the present embodiment, the case where the guide portion 55 formed on the link arm 23 is formed into a long hole has been described, but the present invention is not limited to this configuration. Rails or the like may be used as long as the seat 4 follows the reclining of the backrest 5. Further, the link arm 23 may be provided with a front rotation shaft, and the arm connecting portion 73 may be provided with a guide portion.

<How to switch the seat height>
Next, a method of switching the seat height will be described. In the following description, a method of switching from the basic position to the semi-standing position will be mainly described.
First, as shown in FIG. 3, the engaging pin 95 is pulled out from the first engaging recess 92 to release the engagement between the base arm 26 and the link arm 23. Then, for example, while gripping the rear seat body 61, the seat 4 is lifted upward.

FIG. 7 is an explanatory view for explaining a method of switching the seat height, and is a side view corresponding to FIG.
As shown in FIG. 7, when the seat 4 is lifted upward, the rear seat body 61 rotates upward around the axis Ob, and the link arm 23 rotates upward around the axis Oa. Along with this, the front seat body 62 moves backward while moving upward. At this time, the front side seat body 62 rotates downward around the axis Oct with respect to the rear side seat body 61, so that the front side rotation shaft 76 slides in the guide portion 55 and is attached to the link arm 23. On the other hand, it rotates downward around the axis Od (direction approaching the pivot 41). After that, the engaging pin 95 is made to enter the second engaging recess 93 through the through hole 91. As a result, as shown in FIG. 5, the seat 4 is held in the semi-standing position. When shifting from the basic position to the semi-standing position, the rod 82 of the gas damper 80 extends with respect to the cylinder 81 as the seat connecting pin 75 moves upward.

In the semi-standing position, the downward rotation of the front seat body 62 is restricted by the front rotation shaft 76 contacting the first end edge (lower end edge in FIG. 5) of the guide portion 55 from above. That is, in the semi-standing posture, the front seat 62 is supported from below by the posterior seat 61, the link arm 23, and the gas damper 80. As a result, the front seat body 62 is held above the link arm 23 and the rear seat body 61 with the seat surface facing upward. When switching the seat 4 from the semi-standing position to the basic position, the operation opposite to the above-described operation is performed.

As described above, in the present embodiment, the seat 4 can be changed to the basic position and the semi-standing position, so that the seated person can be supported in both the basic posture and the semi-standing posture.
In particular, according to the present embodiment, since the rear seat body 61 is supported by the backrest 5, the seat 4 tends to move in the front-rear direction in response to the tilt of the backrest 5. Then, the front rotation shaft 76 is displaced in the guide portion 55 in the direction of approaching and separating from the pivot 41, so that the seat 4 follows the tilting motion of the backrest 5.
As a result, it is possible to cope with the diversification of working postures while improving the comfort.

In the present embodiment, the seat 4 is divided into a rear seat body 61 and a front seat body 62, and the basic position and the semi-standing position are switched by the rotational operation of the rear side seat body 61 and the front side seat body 62. And said.
According to this configuration, in the basic position, the seating surfaces of the posterior seat body 61 and the front seating body 62 are integrated to form a seating surface, so that the portion from the buttocks to the thighs of the seated person is stable. Can be supported.
On the other hand, since the seating height in the semi-standing position is determined by the front-rear length of the rear seat body 61, the seat in the semi-standing position is compared with the case where the entire seat is rotated as in the conventional case. The surface height can be lowered. As a result, in the semi-standing position, the buttocks of the seated person can be stably supported with the knees slightly bent. Therefore, an appropriate sitting posture can be obtained in both the basic posture and the semi-standing posture.
Further, since the seat height in the semi-standing position can be adjusted by the front-rear length of the rear seat body 61, the degree of freedom in design and design can be improved.

In the present embodiment, the link arm 23 is rotatably supported by both the front seat body 62 and the backrest bracket 35, and is rotated forward as the front seat body 62 moves between the basic position and the semi-standing position. The moving shaft 76 is configured to move in the guide portion 55.
According to this configuration, the link arm 23 can be made to follow the movement of the seat 4 between the basic position and the semi-standing position, so that the seat 4 can always be stably supported by the link arm 23.

(Second Embodiment)
Next, a modified example of the above-described embodiment will be described. FIG. 8 is a side view of the chair 100 according to the second embodiment. In the following description, the members corresponding to the above-described first embodiment are designated by the same reference numerals, and the description thereof will be omitted.
In the chair 100 shown in FIG. 8, a housing bracket 101 is formed in the housing 43 of the torsion unit 34. The housing bracket 101 projects upward from the housing 43.

The above-mentioned backrest connecting portion 64 of the rear seat body 61 is rotatably connected to the upper end portion of the housing bracket 101 around the axis Ob. That is, the seat 4 (rear seat body 61) is connected to the backrest 5 via the torsion unit 34. Therefore, the seat 4 moves in the front-rear direction around the pivot 41 following the tilt of the backrest 5.

The front seat body 62 includes an arm connecting portion 113 that projects downward from the lower surface of the front main body portion 71. The arm connecting portion 113 is formed with a first guide portion 121 and a second guide portion 122. The guide portions 121 and 122 are formed in elongated holes extending in the front-rear direction. The first guide portion 121 is arranged above and behind the second guide portion 122.

A first link arm 110 and a second link arm 111 are bridged between the housing bracket 101 and the arm connecting portion 113. In the example shown in FIG. 8, the link arms 110 and 111 extend along the front-rear direction.

The rear end portion of the first link arm 110 is connected to the housing bracket 101 via a first rear link shaft 130 extending in the left-right direction. In this case, the rear end portion of the first link arm 110 is rotatably supported by the housing bracket 101 around the axis Op along the left-right direction.
The front end portion of the first link arm 110 is connected to the arm connecting portion 113 via the first front link shaft 131 extending in the left-right direction. Specifically, the first front link shaft 131 is supported by the arm connecting portion 113 through the first guide portion 121. In this case, the front end of the first link arm 110 is configured to be rotatable around the axis Oq along the left-right direction, and the first link arm 110 is connected to the arm as the first front link shaft 131 moves in the first guide portion 121. It is configured to be slidable in the front-rear direction with respect to the portion 113.

The rear end portion of the second link arm 111 is connected to the housing bracket 101 via a second rear link shaft 140 extending in the left-right direction. In this case, the rear end portion of the second link arm 111 is rotatably supported by the housing bracket 101 around the axis Or along the left-right direction.
The front end portion of the second link arm 111 is connected to the arm connecting portion 113 via the second front link shaft 141 extending in the left-right direction. Specifically, the second front link shaft 141 is supported by the arm connecting portion 73 through the second guide portion 122. In this case, the front end portion of the second link arm 111 is configured to be rotatable around the axis Os along the left-right direction, and the second link arm 111 is connected to the arm as the second front link shaft 141 moves in the second guide portion 122. It is configured to be slidable in the front-rear direction with respect to the portion 73.

In the present embodiment, the first link arm 110, the second link arm 111, the housing bracket 101, and the arm connecting portion 113 are each provided in pairs on the left and right.

As described above, in the chair 100 of the present embodiment, the housing bracket 101, the arm connecting portion 113, and the link arms 110 and 111 are rotatably connected as movable links around the axes Op to Os, that is, a so-called four-bar link. It constitutes a mechanism.

FIG. 9 is an explanatory view of the reclining operation, and is a side view corresponding to FIG.
As shown in FIG. 9, in the chair 100 of the present embodiment, since the rear seat body 61 is connected to the housing bracket 101, for example, when the backrest 5 tilts backward from the initial position, it is rearward of the backrest 5. The seat 4 is pulled backward with the displacement to. As a result, the seat 4 moves backward so as to follow the tilt of the backrest 5.

On the other hand, when the backrest 5 returns from the backward tilted position to the initial position, the seat 4 is pushed forward following the forward tilt of the backrest 5 around the pivot 41. As a result, the seat 4 moves forward so as to follow the tilt of the backrest 5. Since the link arms 110 and 111 bridge between the housing bracket 101 and the seat 4, they move in the front-rear direction together with the seat 4 following the tilt of the backrest 5.

FIG. 10 is an explanatory view for explaining a method of switching the seat height, and is a side view corresponding to FIG.
As shown in FIGS. 8 and 10, when the seat 4 is lifted upward, the rear seat body 61 rotates upward around the axis Ob. Along with this, the link arms 110 and 111 rotate upward around the axes Op and Or. As a result, the front seat body 62 moves backward while moving upward. Further, the front seat body 62 rotates downward around the axes Oq and Os. As a result, the front seat 62 is held above the posterior seat 61, and the seating surface of the front seat 62 is held in a semi-standing position facing upward.

Even when two link arms 110 and 111 are used separately from the rear seat body 61 as in the present embodiment, the same effects as those in the above-described embodiment can be obtained.
In particular, in the present embodiment, the front side seat body 62 can be supported from below by the rear side seat body 61 and the link arms 110 and 111 in the semi-standing position, so that the robustness can be improved.

(Third Embodiment)
Next, a third embodiment of the present invention will be described. FIG. 11 is a schematic side view of the chair 200 according to the third embodiment.
In the chair 200 shown in FIG. 11, the backrest 5 is rotatably supported by the support base 3 (support basic body 21) via the pivot axis 203 extending in the left-right direction.

The seat 211 has a basic seat 212 and a semi-standing seat 213 connected to the front end of the basic seat 212.

The seat surface of the basic seat body 212 faces upward at the basic position. The basic seat body 212 supports the portion from the buttocks to the thighs of the seated person in the basic position. The rear end portion of the basic seat body 212 is connected to the backrest 5 via a rear rotation shaft 215 extending in the left-right direction.

The semi-standing seat body 213 is integrally extended downward from the front end of the basic seat body 212. The seating surface of the semi-standing seat body 213 faces forward in the basic position. The seat 211 changes to a basic position in which the basic seat 212 faces upward and a semi-standing position in which the semi-standing seat 213 faces upward by rotating around the rear rotation shaft 215.

A support arm 220 is connected between the support base 3 and the seat 211. The first end of the support arm 220 is connected to the support base 3. The second end of the support arm 220 is supported by the seat 211 (basic seat 212) via a support pin 223 extending in the left-right direction. Specifically, a guide portion 225 extending in the front-rear direction is formed at the second end portion of the support arm 220. In the guide portion 225, a support pin 223 projecting from the basic seat body 212 is arranged so as to be movable in the front-rear direction. Further, the support arm 220 is formed with a communication port 230 that communicates the inside and outside of the guide portion 225. The support pin 223 is configured to be retractable from the guide portion 225 through the communication port 230.

In such a configuration, as shown in FIG. 12, when the backrest 5 is tilted, the seat 211 moves in the front-rear direction along with the tilt of the backrest 5, so that the support pin 223 moves in the guide portion 225 in the front-rear direction. Moving.

As shown in FIG. 11, in order to move the seat 211 from the basic position to the semi-standing position, the support pin 223 is retracted from the guide portion 225 through the communication port 230, and the seat 211 is moved around the rear rotation shaft 215. Rotate. That is, the support arm 220 of the present embodiment supports the seat 211 from below by being connected to the seat 211 via the support pin 223 at the basic position. On the other hand, the support arm 220 is separated from the seat 211 in the semi-standing position. In this way, the support arm 220 supports the seat 211 located at the basic position and allows the seat 211 to move from the basic position to the semi-standing position.

Also in the present embodiment, since the seat 211 follows the tilting motion of the backrest 5, it is possible to improve the comfort and cope with the diversification of the working posture.

(Fourth Embodiment)
Next, a fourth embodiment according to the present invention will be described. FIG. 13 is a perspective view of the chair 300 according to the fourth embodiment as viewed from the front left. In the following description, the members corresponding to each of the above-described embodiments are designated by the same reference numerals, and the description thereof will be omitted as appropriate.
In the chair 300 shown in FIG. 13, the backrest 5 is configured by attaching the upholstery member 32 to the rectangular frame-shaped backrest frame 31 as in the above-described embodiment. The portion of the upholstery member 32 that spans the frame 31a on each side functions as a load-bearing surface that supports the load from the back when the seated person is seated.

14 and 15 are side views of the chair 200 according to the fourth embodiment.
As shown in FIGS. 14 and 15, the horizontal portion 31d of the backrest frame 31 functions as a grip portion that is separated rearward from the load-bearing surface of the tension member 32.
In the present embodiment, the length of the front main body 71 in the front-rear direction is longer than the length of the rear main body 63 in the front-rear direction.

FIG. 16 is a plan view of the chair 300 according to the fourth embodiment.
As shown in FIG. 16, the rear surface of the front main body 71 is a curved surface that is convex toward the rear. Specifically, the rear surface of the front main body 71 is formed following the front surface of the backrest 5 (the front surface of the backrest 5 facing the rear surface of the front main body 71 in the semi-standing position). .. As a result, in the semi-standing position (two-dot chain line in FIG. 16), the rear surface of the front main body portion 71 approaches or abuts on the front surface of the backrest 5.
On the other hand, the front surface of the rear main body 63 is a curved surface that is convex toward the rear. Specifically, the front surface of the rear main body 63 is formed following the rear surface of the front main body 71. As a result, at the basic position (solid line in FIG. 16), the rear surface of the front main body 71 comes close to or abuts on the front surface of the rear main body 63.

As shown in FIGS. 14 and 15, the posterior seat connecting portion 65 extends forward from the boundary portion between the posterior main body 63 and the front main body 71. The posterior seat connecting portion 65 is connected to the front seat connecting portion 72 via the seat connecting pin 75 below the front main body portion 71. In the present embodiment, the front side seat connecting portion 72 is supported by the rear side seat connecting portion 65 via the seat connecting pin 75 so as to be rotatable and slidable.

The link arms 110 and 111 are bridged between the housing bracket 101 and the arm connecting portion 113 as in the second embodiment. The first link arm 110 is bent at an intermediate portion in the front-rear direction. Specifically, the first link arm 110 extends linearly toward the front and then extends upward toward the front. As a result, interference between the first link arm 110 and the rear seat body connecting portion 65 is avoided.

Here, the cover unit 301 is arranged below the seat 4. The cover 301 has a first cover 302 and a second cover 303. In the process of shifting the seat 4 between the basic position and the semi-standing position, the cover unit 301 shifts between the overlapping state of the covers 302 and 303 and the expanded state of the covers 302 and 303. do. The cover unit 301 covers the link arms 110, 111, the arm connecting portion 113, the front portion of the support base 3, and the like from both the lower and left and right sides in both the basic position and the semi-standing position.

The first cover 302 mainly covers the front portion of the support base 3 from the front. Specifically, the first cover 302 is formed in a fan shape when viewed from the left and right directions and in a C shape which opens rearward when viewed from the vertical direction. The rear end portion of the first cover 302 is rotatably supported around the axis Or by the second rear link shaft 140. A first engaging flange portion 302a is formed on the upper end edge of the first cover 302 so as to project toward the inside (rear) of the first cover 302.

The second cover 303 mainly covers the front portion of the support base 3, the link arms 110 and 111, the arm connecting portions 113, and the like from the front and the bottom. The second cover 303 is formed in a triangular shape when viewed from the left and right directions and in a U shape which opens upward when viewed from the front and rear directions.

The rear portion of the second cover 303 covers the first cover 302 in the above-mentioned polymerization state (basic position of the seat 4). That is, the above-mentioned first cover 302 is invisible from the outside at the polymerization position. The rear portion of the second cover 303 is rotatably supported around the axis Or by the second rear link shaft 140. The front portion of the second cover 303 is configured to be rotatable around the axis Os by the second front link shaft 141 and to be slidable in the front-rear direction. That is, the cover 301 moves in synchronization with the second link arm 111 as the cover 301 shifts between the basic position and the semi-standing position.

A second engaging flange portion 303a that projects inward is formed on the rear end edge of the second cover 303. The second engaging flange portion 303a is configured to be able to engage with the first engaging flange portion 302a described above in the process of shifting the cover unit 301 from the polymerized state to the expanded state.

That is, in the process of shifting the seat 4 from the basic position to the semi-standing position, the second front link shaft 141 moves upward, so that the second cover 303 rotates upward around the axis Or. As a result, the second cover 303 is deployed with respect to the first cover 302. After that, the second engaging flange portion 303a of the second cover 303 engages with the first engaging flange portion 302a of the first cover 302 from below, so that the first cover 302 and the second cover 303 rotate around the axis Or. Rotates to. As a result, even in the semi-standing position, there is no gap in the boundary portion between the first cover 302 and the second cover 303. Therefore, in both the basic position and the semi-standing position, the front portion of the support base 3, the link arms 110, 111, the arm connecting portion 113, and the like can be collectively covered by the cover unit 301.

As described above, in this embodiment, in addition to exhibiting the same effects as those of each of the above-described embodiments, the following effects are exhibited.
By making the length of the front main body 71 longer than the length of the rear main body 63, the seating surface area in the semi-standing position can be secured.

In the present embodiment, the posterior seat connecting portion 65 is extended below the front main body 71, so that the front seat 62 is arranged above the posterior seat 61 in the semi-standing position. .. As a result, the seat height of the front seat body 62 in the semi-standing position can be increased as compared with the case where the connecting portions 65 and 72 are connected at the boundary portion between the rear main body portion 63 and the front main body portion 71. Therefore, it is possible to suppress a decrease in the seat surface height in the semi-standing position due to the reduction in the length of the rear main body portion 63.
Moreover, in the present embodiment, by extending the rear seat body connecting portion 65 to the lower side of the front main body portion 71, the posterior seat connecting portion 65 and the front seat connecting portion 72 are rearward from the connecting portion. The front main body 71 can be projected. As a result, in the semi-standing position, the rear end portion of the front main body portion 71 can be brought closer to the backrest 5.

In the present embodiment, since the cover unit 301 is arranged below the seat 4, the design can be improved. In particular, since the cover unit 301 moves in synchronization with the second link arm 111, the designability at both the basic position and the semi-standing position can be improved.

(Modification example)
In the above-described embodiment, the configuration in which the posterior seat body 61 and the front seat body 62 are connected via the seat body connecting pin 75 has been described, but the configuration is not limited to this configuration. For example, as shown in FIG. 17, the posterior seat body 61 and the front seat body 62 may be connected via a flexibly deformable connecting member 330. The connecting member 330 is formed in a bellows shape, for example. In the seat 4 according to the present modification, when the connecting member 330 is bent when shifting between the basic position and the semi-standing position, the posterior seat 61 and the front seat 62 are along the axis C1 in the left-right direction. Rotate around. In the seat 4 of the present embodiment, the posterior seat body 61 and the front seat body 62 are integrally covered with a single tension member 331. The upholstery material 331 is preferably formed of, for example, a stretchable material.

In the seat 4 shown in FIG. 18, the cushion material 61a of the rear seat body 61 and the cushion material 62a of the front side seat body 62 are integrally attached to the upper surface of the same substrate 350. At the central portion of the substrate 350 in the front-rear direction (boundary portion of the cushion members 61a and 62a), for example, a bending starting point portion 350a thinner than the other portions is formed. In the seat 4 according to the present modification, when the substrate 350 is bent from the bending starting point 350a when shifting between the basic position and the semi-standing position, the posterior seat 61 and the front seat 62 are bent. It rotates around the axis C2 along the left-right direction.

The technical scope of the present invention is not limited to each of the above-described embodiments, and includes various modifications to the above-described embodiments without departing from the spirit of the present invention. That is, the configuration and the like given in the above-described embodiment are only examples, and can be changed as appropriate.
For example, in the above-described embodiment, the case where the guide portion (long hole) is formed in the link arm 23 and the support arm 220 has been described, but the present invention is not limited to this configuration. The seat and the link arm 23 or the support arm 220 may be connected to each other via a pin formed on the link arm 23 or the support arm 220.

For example, in the first embodiment described above, the length of the link arm 23 or the like may be changed, and the seating surface of the front seat body 62 in the semi-standing position may be tilted forward or backward.
For example, in the first embodiment, the outer circumference of the front rotating shaft 76 may be covered with an elastic member such as rubber. In this case, an elastic member is interposed between the front rotation shaft 76 and the link arm 23. Therefore, when the seating load is input to the front seat body 62, the elastic member is elastically deformed, so that the front seat body 62 rotates around the axis Occ. Thereby, the angle of the front seat body 62 can be changed according to the seating load.
In the above-described embodiment, the configuration in which the backrest 5 includes the backrest frame 31 and the upholstery member 32 has been described, but the configuration is not limited to this configuration. For example, the backrest may be composed of a cushion body that functions as a load supporting surface and a cover member that covers the back of the cushion body. In this case, for example, a grip portion protruding rearward or upward may be provided at the upper end portion of the cover member.

In addition, it is possible to replace the constituent elements in the above-described embodiments with well-known constituent elements as appropriate without departing from the spirit of the present invention, and each of the above-described modifications may be appropriately combined.

1,100,200 ... Chair 4,211 ... Seat 5 ... Backrest 21 ... Support basic body (support structure)
23 ... Link arm (seat support member)
31d ... Horizontal part (grip part)
41,203 ... Axis (1st axis)
55,225 ... Guide part (variable support part)
61 ... Rear seat (back area)
62 ... Front seat (front area)
71a ... Inclined part 212 ... Basic seat (back area)
213 ... Semi-standing sitting body (front area)
Oa ... Axis (4th axis)
Ob ... Axis (second axis)
Occ ... Axis (third axis)
Od ... Axis (fifth axis)

Claims (2)

Support structure and
A backrest rotatably supported by the support structure around the first axis along the width direction,
Rotates between the first seating position, which is arranged above the support structure and constitutes the first seating surface, and the second seating position, which constitutes the second seating surface located above the first seating surface. Possible, with the seat supported by the backrest,
It is provided with a seat support member that is supported by the support structure, supports at least the seat located at the first seating position, and allows the seat to move from the first seating position to the second seating position.
Between the seat and the seat support member, the seat is supported by the seat support member at the first seating position, and the seat is rotated with the rotation of the backrest around the first axis. A variable support that allows movement in the depth direction is provided ,
The seat is
A first seat body located on the inner side in the depth direction and rotatably supported by the backrest around the second axis along the width direction.
It has a second seat body that is located on the front side in the depth direction with respect to the first seat body and is rotatably supported by the first seat body around a third axis along the width direction. death,
At the first seating position, the seating surface of the first seating body and the seating surface of the second seating body are connected to form the first seating surface.
In the second seating position, the first seat is arranged so as to extend upward from the second axis, the second seat is located above the first seat, and the seat of the second seat. A chair characterized in that a second seating surface is formed by a surface. Support structure and
A backrest rotatably supported by the support structure around the first axis along the width direction,
Rotates between the first seating position, which is arranged above the support structure and constitutes the first seating surface, and the second seating position, which constitutes the second seating surface located above the first seating surface. Possible, with the seat supported by the backrest,
It is provided with a seat support member that is supported by the support structure, supports at least the seat located at the first seating position, and allows the seat to move from the first seating position to the second seating position.
Between the seat and the seat support member, the seat is supported by the seat support member at the first seating position, and the seat is rotated with the rotation of the backrest around the first axis. A variable support that allows movement in the depth direction is provided,
The seat support member
A first end portion rotatably connected to the support structure about the fourth axis along the width direction, and
It has a second end portion that is located on the front side in the depth direction with respect to the fourth axis and is rotatably connected to the seat around the fifth axis along the width direction.
The variable support portion is characterized in that it allows displacement of the fifth axis in a direction approaching and separating from the first axis as the seat moves between the first seating position and the second seating position. to that chair.

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