JP3140382B2 - Chair - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chair in which at least one of a seat and a backrest can be tilted. More specifically, the present invention relates to a mechanism for adjusting a reaction force against tilting of a seat or a backrest.

[0002]

2. Description of the Related Art In a chair in which a seat is tilted against a reaction spring such as a compression coil spring, for example, Japanese Utility Model Laid-Open No.
As shown in Japanese Patent Application Laid-Open No. 09646, an initial pressure reaction force adjusting mechanism for a reaction force spring is provided. This initial pressure reaction force adjustment mechanism adjusts the length of the reaction force spring by manually turning a screw shaft coaxial with the reaction force spring, and changes the relationship between the load on the seat and the tilt angle of the seat. Is what you do.

On the other hand, conventionally, a chair in which a seat portion and a backrest are linked in accordance with a posture of a sitting person has been developed so as to make a sitting posture easy. A mechanism that does not simply link the tilting of the backrest and the seat, but does not press against the back of the seated person's thigh when the seat swings around its front and tilts backwards is desired. It is rare. To meet such a demand, for example, a chair disclosed in Japanese Patent Application Laid-Open No. 4-193108 has been proposed.

In this chair, as shown in FIG. 21, a seat 103 is attached to the upper portion of a front seat frame 101 and a rear seat frame 102, and the rear seat frame 102
Is provided with a backrest (not shown) via a connecting portion 104 and a backrest mounting frame 105. When the occupant applies a load to the backrest and tilts the backrest, the rear seat frame 1
02 rotates about the second shaft 106, and the rear part of the seat tilts downward.

On the other hand, in a swivel chair or the like having a backrest, a back support rod for supporting the backrest, a seat receiving portion for supporting the back support rod,
A leg supporting the seat receiving portion and a seat attached to the seat receiving portion are provided. As described above, in the chair which is a finished product by combining the constituent members such as the backrest and the seat, the design of the shape and color of each constituent member is designed in consideration of the overall design of the chair.

[0006]

However, in the chair provided with the initial pressure reaction force adjusting mechanism using the reaction force spring described above,
Since the initial pressure reaction force adjusting mechanism adjusts the length of the reaction force spring by rotating a screw shaft coaxial with the reaction force spring, the reaction force of the reaction force spring is received when the screw shaft rotates. For this reason, when compressing the reaction spring by tightening the screw shaft, or when rotating the screw shaft with the reaction spring fully compressed,
It was difficult to rotate the screw shaft with a light force. In particular, women and other people with weak grips could not increase the initial pressure too much.

On the other hand, in the chair shown in FIG. 21, the backrest tilts in conjunction with the load applied to the seat portion 103 at the same time. When this is done, the rear of the seat portion 103 sinks and tilts, and at the same time, the backrest also tilts rearward. And immediately after that, the rear seat frame 102
Is pushed back by the cushioning member 107 made of a compression coil spring or the like, and the backrest hits the back of the occupant, giving the occupant a discomfort.

On the other hand, in the chair which is a finished product by combining the above-mentioned components, the seat, the backrest and the leg are attached to each other in consideration of the overall design of the finished chair. Therefore, not only the respective components but also the mounting structure of the seat receiving portion and the back support rod has a unique structure for each unique design of the chair.
That is, it is extremely difficult to assemble a backrest or a back support rod of a chair of a certain design as a backrest or a back support rod of a chair of another design. For example, it is possible to change the height of the backrest with respect to the back support rod of the same shape, but to change the shape of the back support rod itself, for example, to form two back support rods on both sides at the rear part of the seat support. It has been extremely difficult to make it possible to replace the provided back support rod with a single back support rod formed in the center of the rear part of the seat receiving part. For this reason, as much as the number of chair designs, a leg, a seat, and a backrest, as well as a seat receiving portion and a back support rod for assembling them, are required, and it is not possible to reduce component costs by sharing constituent members.

Accordingly, an object of the present invention is to provide a chair which can easily adjust a reaction force against tilting of a seat. Another object of the present invention is to provide a chair in which the backrest does not hit the back of the occupant even when the user sits vigorously on the seat. A further object of the present invention is to provide a chair in which a back support rod and a backrest of different designs can be attached to a common seat.

[0010]

In order to achieve the above object, according to the present invention, there is provided a seat receiving member attached to a seat, and a leg attached to a leg for swingably supporting the seat receiving member. In a chair provided with a seat receiving portion that supports the seat portion in a tiltable manner with the side fixing member, the chair is swingably interposed between the seat receiving member and the leg side fixing member so that the chair can be expanded and contracted to the original position with respect to the seat receiving member. A reaction force unit that applies a reaction force to be returned, and a reaction force adjustment mechanism that swings the reaction force unit without changing the amount of expansion and contraction, changes the inclination with respect to the seat receiving member, and maintains the inclined state. I am preparing for it.

Therefore, by tilting the reaction force unit by the reaction force adjusting mechanism, the amount of expansion and contraction of the reaction force unit with respect to the tilting of the seat portion is changed. That is, when the longitudinal direction of the reaction force unit is the same as the direction of the external force that expands and contracts the reaction force unit, the amount of expansion and contraction of the reaction force unit is larger than when the longitudinal direction and the direction of expansion and contraction of the external force are different.
Therefore, when the tilt angle of the reaction unit is changed, the amount of expansion and contraction of the reaction unit with respect to the tilt of the seat changes, and the reaction force with respect to the tilt of the seat changes. Specifically, when the longitudinal direction of the reaction unit is the same as the direction of the external force that expands and contracts the reaction unit, the reaction force against the tilt of the seat is maximized, and as the reaction unit tilts, the reaction against the tilt of the seat is The reaction force decreases.

According to a second aspect of the present invention, there is provided a chair in which a back support rod for supporting a backrest is swingably supported by a seat receiving portion attached to a leg portion so that the backrest can be inclined. A reaction force unit that is swingably interposed between the support rod and the seat receiving portion and applies a reaction force to the seat receiving portion to return to the original position by expansion and contraction; And a reaction force adjusting mechanism for changing the tilt with respect to the back support rod and maintaining the tilt state.

Therefore, by tilting the reaction force unit by the reaction force adjusting mechanism, the amount of expansion and contraction of the reaction force unit with respect to the tilt of the backrest changes. Therefore, the reaction force against the tilt of the backrest changes.

Further, the invention according to claim 3 is a seat receiving member attached to the seat portion, a leg side fixing member attached to the leg portion for swingably supporting the seat receiving member, and a seat receiving member or leg side. A chair that has a back support rod that is swingably supported by the fixed member and that supports a backrest that tilts in conjunction with the tilt of the seat receiving member, and that tilts the backrest in conjunction with the tilt of the seat. , Between the seat receiving member and the leg-side fixing member or between the back support rod and the seat receiving member or the leg-side fixing member so as to be able to swing and return to the original position with respect to the seat receiving member or the back supporting rod by expansion and contraction. And a reaction force adjustment unit that swings the reaction force unit without changing the amount of expansion and contraction to change the inclination with respect to the seat receiving member or the back support rod and maintain the inclined state. And a mechanism.

Therefore, by tilting the reaction force unit by the reaction force adjusting mechanism, the amount of expansion and contraction of the reaction force unit with respect to the tilting of the backrest and the seat changes. Therefore, the reaction force against the tilt of the backrest and the seat changes.

According to a fourth aspect of the present invention, there is provided a seat receiving member attached to a seat portion, a leg side fixing member attached to a leg portion for swingably supporting the seat receiving member, and a seat receiving member or leg side. A back support rod that is supported by the fixed member so as to be swingable and supports a backrest that tilts in conjunction with the tilt of the seat receiving member,
In a chair in which the backrest is tilted in conjunction with the tilt of the seat, an unlocked state that can freely expand and contract with no reaction force, and a seat receiving member that can expand and contract while generating a reaction force at an arbitrarily set position and A gas spring that can be switched to a locked state in which the backrest returns to the locked position and applies a reaction force is interposed between the back support rod and the seat receiving member or the leg-side fixing member, and is expanded and contracted in accordance with the tilting thereof. And

Therefore, since the gas spring can be set to an arbitrary length and locked, the backrest and the seat can be locked at an arbitrary tilt angle. Also, since the length of the gas spring is almost maintained against sudden load,
Even if the seated person is seated vigorously and a vertical impact load is applied to the seat, the seat and the backrest are maintained in the locked position without tilting.

According to a fifth aspect of the present invention, there is provided a seat receiving member attached to a seat portion, a leg side fixing member attached to a leg portion for swingably supporting the seat receiving member, and a seat receiving member or a leg side. A back support rod that is supported by the fixed member so as to be swingable and supports a backrest that tilts in conjunction with the tilt of the seat receiving member,
In a chair in which the backrest is inclined in conjunction with the inclination of the seat portion, the backrest is tiltably interposed between the seat receiving member and the leg-side fixing member or between the back support rod and the seat receiving member or the leg-side fixing member. A reaction force unit that applies a reaction force to the seat receiving member or the back support rod to return to the original position by expansion and contraction, and swings the reaction force unit without changing the amount of expansion and contraction to the seat reception member or the back support rod. Equipped with a reaction force adjustment mechanism that changes the tilt and maintains the tilt state, and can be freely expanded and contracted with no reaction force, and expands and contracts while generating a reaction force at an arbitrary set position A gas spring, which can be switched to a locked state in which the seat receiving member and the backrest return to the locked position to apply a reaction force, is interposed between the back support rod and the seat receiving member or the leg side fixing member, and these tilt. To expand and contract with .

Therefore, by tilting the reaction force unit by the reaction force adjusting mechanism, the amount of expansion and contraction of the reaction force unit with respect to the tilting of the backrest and the seat portion is changed, and the reaction force with respect to the tilting of the backrest and the seat portion is changed. Is done. At the same time, the backrest and the seat are locked at an arbitrary tilt angle, and the seat and the backrest are maintained in the locked position without tilting even if a seated person sits vigorously and a vertical impact load is applied to the seat. You.

Further, in the chair according to the present invention, the reaction force unit or the reaction force adjustment mechanism is provided with a display member which is interlocked with the tilting of the reaction force unit, and covers at least the reaction force adjustment mechanism and the reaction force unit. A cover is provided, and the cover is provided with a display unit from which a display member is exposed. Therefore, by displaying the angle of the tilt of the reaction unit outside the cover, the magnitude of the reaction force against the tilt of the seat and the backrest is indicated outside.

According to a seventh aspect of the present invention, there is provided a chair, comprising: a back support rod integrated with the back support rod and extending in the width direction of the chair; and a back support rod support shaft formed on a seat receiving member or a leg-side fixing member. A shaft holding portion that is fitted and supported, and at least a portion of the back support rod that fits with the shaft holding portion has a non-circular cross section having a long diameter portion and a short diameter portion, and the shaft holding portion has Accommodates a radial opening wider than the short diameter part of the back support rod and narrower than the long diameter part, and accommodates the back support rod inserted from the opening and fixed at a position shifted circumferentially from the opening And a back support rod is inserted into the housing of the shaft holding part from the opening and rotated to be engaged.

Accordingly, the seat support member or the leg-side fixing member and the back support rod are engaged and connected only by inserting the back support rod support shaft from the opening into the receiving portion in the shaft holding portion. The backrest of a different design is attached to the seat receiving part by the common use of the shape and dimensions of the rod support shaft. In other words, the backrest and the back support rod of another plurality of designs are attached to the seat portion and the seat receiving portion of a certain design.

Further, in the chair according to the eighth aspect, the shaft holding portion is constituted by a bearing having an opening through which the back support rod is passed in the radial direction, and an adapter member rotatable inside the bearing. An accommodating portion that holds the spine support shaft non-rotatably on the member, a radial opening wider than the short diameter portion of the spine support shaft and narrower than the long diameter portion, and a rotation rotatably supported by the bearing. A shaft portion and a fixing portion fixed to the back support rod side are provided.

Therefore, when attaching the back support rod and the backrest to the seat receiving portion, the rotating shaft portion of the adapter member is mounted on the bearing. Then, the back support rod is passed through the opening of the bearing and the opening of the adapter member, and is accommodated in the accommodation portion of the adapter member. Further, the back support rod and the support shaft of the back support rod and the fixing portion of the adapter member are connected and integrated. Since the rotation shaft portion of the adapter member can rotate with respect to the bearing of the seat receiving portion, the backrest and the back support rod can be tilted with respect to the seat receiving portion.

According to a ninth aspect of the present invention, in the chair of the ninth aspect, when the spine support shaft is rotated, the spine support shaft is caught in the accommodating portion of the adapter member and cannot pass through the opening of the adapter member. Is formed, and the fixing portion of the adapter member is fixed to the back support rod side in a state where the back support rod support shaft is hooked on the locking portion. Therefore, the back support rod does not come off the adapter member, and the backrest does not come off the seat receiving portion.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below in detail based on an example of an embodiment shown in the drawings. FIGS. 1 to 19 show a first embodiment of a chair in which a backrest and a seat are linked. This chair includes a seat fitting 8 as a seat receiving member attached to the seat 5, and a leg-side fixing member (hereinafter, referred to as a “fixing member”) attached to the pillar 6, which is a leg, for swingably supporting the seat receiving tool 8. (Referred to as support metal fittings) 7 to support the seat 5 in a tiltable manner. The chair includes a reaction force unit 33 which is swingably interposed between the seat fitting 8 and the support fitting 7 and applies a reaction force for returning the seat fitting 8 to the original position by expansion and contraction. The reaction force adjusting mechanism 5 that swings the reaction force unit 33 without changing the amount of expansion and contraction and changes the inclination with respect to the seat bracket 8 and maintains the inclination state.
4 is provided.

As shown in FIGS. 1 and 2, the seat 3 includes a seat 8 and a support 7 for swingably supporting the seat 8 and the back support rod 2. And a shaft holding portion 29 that holds the back support rod 4 that supports the back support rod 2. The seat fitting 8 and the support fitting 7 are connected to each other at a front portion so as to be swingable by a rotating shaft 41, and are connected at a rear portion by an adapter member 31 and a link plate 35.

The seat bracket 8 includes a square rectangular mounting plate 8a, a pair of outer plates 8b, 8b projecting downward from both left and right side edges of the mounting plate 8a, and each outer plate 8a.
b, 8b, a pair of inner plates 8c, 8c formed substantially parallel to the outer plates 8b, 8b and protruding forward and backward of the mounting plate 8a;
Bearings 60, 60 formed at the rear of the inner plates 8c, 8c are provided.

On the upper side of the mounting plate 8a, a seat plate of the seat portion 5 is screwed by a bolt (not shown). A shaft support hole 8d is formed at the front of the inner plates 8c, 8c. The shaft support hole 8 d is swingably attached to the front part of the support fitting 7 by the rotation shaft 41. Further, the outer plate 8
Shaft support holes 8e, 8e are formed at the rear of b, 8b. The shaft support holes 8e, 8e pass through the inner plates 8c, 8c. As shown in FIGS. 1 and 12, the reaction force unit 33 is provided in the shaft support holes 8e, 8e.
4 so as to be swingable.

A projection 8f is formed on the outer surface of the outer plates 8b, 8b. The projection 8f supports a seat plate (not shown) that supports the seat portion so as to be slidable back and forth, but is not particularly used in the present embodiment.

As shown in FIGS. 1 and 2, the support member 7 is composed of two vertical plates 7a,
have. Each vertical plate 7a, 7a is a horizontal connecting plate 7
b. A cylindrical leg receiving cylinder 7c that accommodates the upper end of the pillar 6 is formed at the rear part of the support fitting 7. A shaft support hole 7d is formed at the front of the support fitting 7. The shaft support hole 7d is
Thus, it is swingably attached to the shaft support hole 8 d of the seat bracket 8.

As shown in FIGS. 1, 2, 12 and 15 to 18, the reaction force unit 33 and the reaction force adjustment mechanism 54 are attached from the center to the front of the support fitting 7 and the seat fitting 8. Have been. The reaction force unit 33 includes a biasing spring 55 composed of a compression coil spring, and a connection fitting 56 that connects the biasing spring 55 and the support fitting 7. In the present embodiment, the biasing spring 55 is a compression coil spring, but is not limited to this and may be a gas spring or the like.

As shown in FIG. 12, the connecting fitting 56 includes two vertically long vertical plates 56a, 56a, and the vertical plates 56a, 56a.
A ceiling plate 56b connecting the upper portions of the vertical plates 56a,
A bottom plate 56c that protrudes outward from the lower end of 6a;
A spring enclosing plate 56d having a U-shaped cross section is provided above the bottom plate 56c to form a space in which only the upper side is open.
The spring enclosing plate 56d includes a bottom plate 56c and a vertical plate 56c.
a is attached by welding. However, the connection fitting 56 is not limited to one formed by attaching another member by welding or the like, and may be one integrally formed.

The connecting fitting 56 is attached to the supporting fitting 7. That is, the upper portions of the vertical plates 56a, 56a are pivotally connected to the shaft support hole 7g, which is the upper portion of the center of the support fitting 7 and coaxial with the support pin 34, by the rotary shaft 57. The vertical plate 56a of the connection fitting 56 and the spring enclosing plate 5
The lower end of the biasing spring 55 is accommodated in a space surrounded by the bottom plate 6d and the bottom plate 56c.

A spring receiving plate 58 and an initial pressure adjusting screw 59 are provided between the biasing spring 55 and the bottom plate 56c.
The spring receiving plate 58 has an upper protrusion and a lower recess,
This projection is fitted on the inner peripheral portion of the biasing spring 55. A screw hole is formed at the center of the bottom plate 56c, and the initial pressure adjusting screw 5 is formed.
9 is screwed. The tip of the initial pressure adjusting screw 59 is fitted into the recess of the spring receiving plate 58. Therefore, by tightening the initial pressure adjusting screw 59, the spring receiving plate 58
Since the urging spring 55 is compressed away from c, the initial pressure can be adjusted. Then, the initial pressure adjusting screw 59 is tightened. For this reason, the magnitude of the initial pressure of each chair can be unified.

The upper portion of the biasing spring 55 is provided between the outer plate 8b and the inner plate 8c of the seat bracket 8 and the spring holding plate 64 and the mounting member 65.
And the support pin 34. Fixture 65
Is rotatably supported between the outer plate 8b and the inner plate 8c by a support pin 34 whose central portion is reduced in diameter. Protrusions are formed on the upper and lower portions of the spring holding plate 64, and the upper protrusions are fitted into through holes formed on the lower portion of the fixture 65. Then, by engaging the projection with the reduced diameter portion of the support pin 34,
The support pins 34 are prevented from falling off. The lower protrusion of the spring holding plate 64 is fitted to the inner peripheral portion of the biasing spring 55.

Further, a spacer plate 66 perpendicular to the vertical plate 7a is formed around the wire support 53 attached to the vertical plate 7a of the support fitting 7. The spacer plate 66 also has an arc-shaped portion centered on the support pin 34 extending to the front of the wire support 53. Also,
A spacer member 67 is attached to the vertical plate 56a of the connection fitting 56 facing the vertical plate 7a on the opposite side of the vertical plate 7a on which the spacer plate 66 is formed. Therefore, the connecting fitting 56 does not shift in the width direction with respect to the supporting fitting 7. Further, since the spacer plate 66 has an arcuate portion, the vertical plate 56a is in contact with the spacer plate 66 even when the reaction unit 33 swings.

Therefore, as shown in FIGS. 1 and 12, the weight of the occupant hung on the seat bracket 8 via the seat portion 5 can be transferred via the support pin 34, the mounting member 65, and the spring pressing plate 64. Acting on the urging spring 55, the load from the urging spring 55 is applied to the spring receiving plate 58, the initial pressure adjusting screw 59, and the connecting fitting 5
It is supported by the support fitting 7 via the support shaft 6 and the support shaft 57.

In the present embodiment, since the reaction force units 33, 33 are provided on both left and right sides of the support fitting 7, the right and left balance is good when the seat fitting 8 swings. However, it is not limited to the one provided on both the left and right sides, and may be provided only on one side. In this case, the number of parts can be reduced, and the size can be reduced. Further, in the present embodiment, the urging spring 55 is configured to be urged in the compression direction, but is not limited to this, and may be configured to be urged in the pulling direction. further,
In the present embodiment, the biasing spring 55 is configured to be tiltable substantially forward of the vertical, but is not limited thereto, and may be tiltable rearward. In the present embodiment, the biasing spring 5
5 is received by the support pin 34 and the rotation shaft 57 disposed coaxially, but is not limited thereto. For example, the support plate 34 may be formed on the vertical plate 7a of the support fitting 7 in an arc shape centered on the support pin 34. As in a structure in which a through hole is formed, the upper portion of the biasing spring is swingably locked to the support pin 34, and the lower portion of the biasing spring is supported by the arc-shaped through hole of the vertical plate 7a. The position receiving the urging force may not be coaxial.

As shown in FIGS. 2 and 15 to 18, the reaction force adjusting mechanism 54 includes a unit lever 68, an adjusting lever 69, a slider 70, and a rotary screw 71. The unit lever 68 is fixed to the inner surface of one of the vertical plates 56a of the connection fitting 56 by welding or the like. The front end of the adjustment lever 69 is supported by a projection at the front end of the support fitting 7 so as to be swingable about the shaft 41. The rear end of the adjustment lever 69 is swingably connected to the unit lever 68 by a pin joint. Here, the adjustment lever 69
The through hole formed at the rear end is slightly elongated to prevent the unit lever 68 from interfering with the pin. A vertical groove 72 is formed at the front of the outer surface of the vertical plate 7a, and bearing plates 73, 73 having through holes are formed at upper and lower portions of the vertical groove 72. Between the vertical groove 72 and the adjustment lever 69,
A slider 70 is provided.

The slider 70 has a vertically long sliding projection 70a.
And a supporting projection 70b on the surface opposite to the sliding projection 70a.
And a screw hole 70c penetrating vertically. The sliding projection 70a is fitted in the vertical groove 72, and the slider 70 is slidable vertically with respect to the vertical plate 7a. Also,
The support projection 70b is swingably attached to the adjustment lever 69. Here, the through hole formed in the adjustment lever 69 is slightly elongated to prevent interference with the support protrusion 70b. Furthermore, the rotary screw 71 is attached to the through hole of each bearing plate 73, 73 so as not to come off rotatably. The rotary screw 71 is screwed into a screw hole 70c of the slider 70. A grip 74 is attached to the lower end of the rotary screw 71.

Therefore, by rotating the grip 74, the slider 70 is guided by the vertical groove 72 and slid in the vertical direction. As a result, the adjustment lever 69 is
Rocked around. Then, the adjustment lever 69 swings the unit lever 68, and the reaction force unit 33 swings. Here, depending on the tilt angle of the reaction force unit 33,
Since the compression length of the urging spring 55 with respect to the predetermined tilt angle of the seat 5 and the backrest 1 is changed, the magnitude of the reaction force of the seat 5 and the backrest 1 can be adjusted. That is, FIG.
When comparing the case where the swinging direction of the washer 8 is substantially coincident with the direction of expansion and contraction of the biasing spring 55 as shown in FIG. 5 and the case where these directions are shifted as shown in FIG.
The length by which the urging spring 55 should be compressed in order to incline at a predetermined angle becomes larger when the swinging direction and the expanding and contracting direction match. Therefore, when the swing direction and the expansion / contraction direction match, the reaction force against the tilting of the seat portion 5 and the backrest 1 is maximized.

In this embodiment, the reaction force adjusting mechanism 54 includes the unit lever 68, the adjustment lever 69, the slider 70, and the rotary screw 71. However, the reaction force unit 33 is tilted to change the tilt state. Of course, the mechanism is not limited to this as long as it can be maintained.

On the other hand, as shown in FIGS. 1 and 19, a cover 75 is attached around the seat receiving portion 3. A display pin 76 as a display member is attached to an outer surface of the spring surrounding plate 56d of the connection fitting 56. In a portion of the side surface of the cover 75 facing the swing range of the display pin 76, a display window 75a is formed as a display unit including a circular arc-shaped through hole along the swing position of the display pin 76.
Therefore, the position of the display pin 76 of the reaction unit 33 is
It can be confirmed from outside through the display window 75a. Thus, the inclination angle of the reaction force unit 33, that is, the seat portion 5 and the backrest 1 can be confirmed only by looking at the magnitude of the reaction force against the tilting. In the present embodiment, the display pin 76 is fixed to the outer surface of the spring enclosing plate 56d, but is not limited to this.

The colors of the cover 75 and the display pins 76 are, for example, those of the display 75
It is preferable that the position of the display pin 76 is visually raised to make it easy to confirm the position, for example, by turning red. Further, FIG.
As shown in FIG. 9, a display 75b indicating the magnitude of the reaction force of the seat 5 or the like in front of, behind, or both of the display window 75a.
Is preferably added.

On the other hand, as shown in FIGS. 1 to 10, the chair of this embodiment is provided with a back support rod 4 having a longitudinal direction in the width direction of the chair on the back support rod 2 side and a seat support section 3 side. A shaft holding portion 29 having radial openings 30 and 62 through which the back support rod 4 can be inserted is provided on the back support rod 4.
It is designed to be inserted into the shaft holding portion 29 from 0, 62 and rotated to be engaged.

The back support rod 4 is provided at least with the shaft holder 2.
9 is formed in a non-circular cross section having a long diameter portion L1 and a short diameter portion L2. For example, in the case of the present embodiment, a so-called double D-cut shaft (shaft having an oval cross section) is formed by chamfering the circumferential surface of a shaft having a circular cross section with two parallel surfaces. In the present embodiment, the back support rod 4 is a double D-cut shaft. However, the present invention is not limited to this, and it may be a polygonal shaft such as a hexagonal or quadrangular cross section or an elliptical cross section.

As shown in FIGS. 5 and 6, the left and right back support shafts 4 and 4 are connected by a connection shaft 26. The connecting shaft 26 has a cross-shaped cross section. However, the present invention is not limited to this.
4 may be formed by one shaft having the same cross-sectional shape. In addition, if the left and right back support rods 2 are connected at the upper part or the like, the connecting shaft 26 may be omitted. The outer ends of the back support rods 4 and 4 are integrated with the horizontal arms 2b and 2b at the front of the back support rods 2 and 2, respectively. This horizontal arm 2b,
2b has a shape in which the front portions of the back support rods 2 are bent inward.

As shown in FIG. 2, FIG. 4, and FIG. 6, the portion of the horizontal arm 2b of the back support rod 2 that is continuous with the back support rod 4 is
A back support rod arm 45 having a shape protruding forward is formed. A through hole 45 a is formed at the tip of the back support rod arm 45. As shown in FIG. 3 and FIG.
In the figure, the dish-shaped counterbore portion 45b is not a perfect circular shape but an elliptical shape which is inclined so that the upper portion is shallower and the lower portion is deeper, and a clearance is provided in a hole portion through which the shaft portion of the screw passes. The back support arm 45 is moved in the direction of the arrow shown in FIG. 7 by tightening a screw that is not provided, so as to eliminate play between the back support arm 45 and the lever 61 of the adapter member 31.

Further, as shown in FIGS. 5 and 6, the rear portions of the left and right back support rods 2, 2 are integrally connected by a support plate 14. In this embodiment, the back support rod 4, the connecting shaft 26, the back support 2, and the support plate 14 are integrally formed by zinc die casting. However, the invention is not limited to this, and it is possible to integrally form each part as an individual member, not limited to the integrally molded product by aluminum die casting alloy or plastic, and integrate each member by welding, bonding, press-fitting, etc. No problem. For example, the back support rods 2, 2 and the support plate 14, which are integrally formed of plastic, and the metal back support rods 4, 4 and the connection shaft 26 may be press-fitted. Further, the back support rods 2, 2 and the support plate 14 may be connected by screws. Further, for example, when the back support rod 4, the back support rod 2, and the support plate 14 are all made of separate metal members, they can be assembled by welding or screwing each other.

As shown in FIGS. 1 to 4 and FIGS. 8 to 10, the shaft holding portions 29 of the seat receiving portion 3 have a cylindrical shape having a C-shaped cross section provided with an opening 30 at an upper portion. Bearing 60
And an adapter member 31 rotatably accommodated inside.

In this embodiment, the opening 30 is formed by a notch in the axial direction. The size of the opening 30 is such that the rotation shaft 32 of the adapter member 31 does not protrude and the short diameter portion L2 of the back support rod 4 can pass through. That is, only when the back support rod 4 is inserted in a specific direction, it can pass through the opening 30 and be housed in the housing 63 of the adapter member 31. still,
In the present embodiment, since the adapter member 31 is interposed between the back support rod 4 and the bearing 60, the upper limit of the size of the opening 30 is such that the rotation shaft 32 of the adapter member 31 does not protrude. However, when the adapter member 31 is not interposed, the length is smaller than the long diameter portion L1 of the back support rod support shaft 4.

The adapter member 31 has a cylindrical base 37, a rotating shaft 32 narrower than the base 37, and a lever 61 as an arm-shaped fixing part, and is integrally formed of metal such as zinc or aluminum die-cast alloy or plastic. Is molded. A notch is provided in the upper part of the rotating shaft part 32 and the base part 37 to form a radial opening 62. As shown in FIGS. 3 and 10, the interval between the openings 62 is
Narrower diameter part L2 narrower than long diameter part L1 of back support rod 4
It is larger than the size. The inside of the rotation shaft portion 32 and the base portion 37 constitutes a housing portion 63 for housing the back support rod 4 in a non-rotatable manner.

An engaging portion 63a is formed in a part of the portion corresponding to the ceiling of the housing portion 63. This locking portion 63a
As shown by the phantom line in FIG. 10, when the back support rod 4 inserted into the housing portion 63 through the opening 62 rotates clockwise until it comes into contact with the wall surface 63b and is housed in a predetermined position. The upper right corner of the back support rod 4 is caught so that the back support rod 4 does not fall out of the opening 62 at the same inclination angle.

In this embodiment, since the back support rod 4 is formed in a double D-cut shape, the locking portion 63a is provided.
A part of the corner of the back support rod 4 is caught on the support rod 4.
Either side of the back support rod 4 is caught on the support rod. For this reason, also in this case, the back support rod 4 does not fall out of the opening 62 at the same inclination angle.

Further, as shown in FIG.
One rotating shaft portion 32 is rotatably accommodated in a bearing 60. A sleeve 47 having a C-shaped cross section made of plastic or a sintered oil-impregnated alloy having excellent lubricity is fitted on the outer peripheral surface of the rotating shaft portion 32. The cutout portion of the sleeve 47 is overlapped with the position of the opening 62 of the rotating shaft 32. When the rotating shaft 32 rotates with respect to the bearing 60, the outer peripheral surface of the sleeve 47 slides on the inner peripheral surface of the bearing 60.

Then, as shown in FIG.
0, the total length of the widthwise outer dimensions of the seat bracket 8 and the thickness of the bases 37, 37 of the left and right adapter members 31, 31 is equal to the length of each of the back support rods 4, 4 and the connecting shaft 26. It is slightly shorter than the full length. As a result, even if the back support rods 4, 4 attempt to move in the axial direction, the horizontal arms 2b, 2b of the back support rods 2, 2 abut on the bases 37, 37 and hardly move. Does not shift in the width direction. Further, since the bases 37, 37 contact the horizontal arms 2b, 2b of the back support rods 2, 2, the adapter members 31, 3 are provided.
1 does not move outward in the axial direction. Therefore, the adapter member 31 does not fall out of the bearing 60.

As shown in FIGS. 1 to 4 and FIGS. 8 to 10, on the outer peripheral surface of the base 37 of the adapter member 31, a lever portion 61 protruding forward is formed. Lever part 61
Of the front end of the link plate 35
It is swingably attached to zero. In addition, lever part 6
1 from the base 37 to the center, a fixed surface 6 having a size equal to the size of the back support arm 45 and raised in the width direction of the chair.
1c is formed. The back support arm 45 is attached to the fixing surface 61c. Spine arm 45 of fixed surface 61a
A screw hole 61a formed of a perfect circular through hole is formed at a position facing the through hole 45a.

When attaching the back support rod 2 to the seat receiving portion 3, the sleeve 47 is attached to the rotating shaft portion 32 of the adapter member 31, and then the rotating shaft portion 32 is attached to the bearing 60. Then, the opening 62 of the adapter member 31 and the opening 30 of the bearing 60 are overlapped and passed through the back support rod 4. At this time, the back support rod 4 is inserted at an inclination angle at which the chamfered plane of the back support rod 4 is parallel to the insertion direction. After the back support rod 4 is received in the storage portion 63 inside the adapter member 31, the back support rod 2 is tilted backward. Thereby, the back support rod 4 rotates clockwise in FIG. 3 until the back support rod 4 comes into contact with the wall surface 63b.
One of the corners is caught by the locking portion 63a. For this reason,
The back support shaft 4 has an opening 62 at the same inclination angle.
Can not pass.

Further, in this state, the through hole 45a of the back support arm 45 and the screw hole 61a of the lever portion 61 are connected to the back support arm 4
The screw is screwed from the 5 side with a set screw 46. At this time, as shown in FIG. 3 and FIG. 7, by tightening the set screw 46, the head of the set screw 46 becomes the through hole 4 of the back support arm 45.
Since the counterbore 45b of 5a is pressed, the counterbore 45
The deep part of b will be screwed. That is,
Since the deep portion of the counterbore portion 45b is below the back support arm 45, the back support arm 45 is moved upward with respect to the lever 61 as indicated by the arrow. As a result, as shown in FIG. 3, the back support rod 4 is screwed in a state of being urged clockwise against the adapter member 31, so that the back support rod 4 is The hooked state is maintained, and it does not pass through the opening 62 and fall out.

As shown in FIGS. 1, 2 and 11,
The link plate 35 is swingably attached to a position near the rear of the center of the support fitting 7. The link plate 35 has a substantially triangular plate shape. Of the three corners, pins 38 and 39 protruding inside the chair are formed at the upper corner and the lower corner, and the front corner is formed. Has a pin 4 protruding outside the chair
0 is formed. The link plate 35 includes the pins 38, 3
9 and 40 and formed by insert molding such as zinc die casting.

A through hole 61b at the tip of the lever 61 is swingably fitted to the front pin 40. In this fitting portion, a cylinder-shaped sliding cylinder 36 that has been sintered is interposed. Therefore, the swing of the lever portion 61 and the link plate 35 is smoothly performed. The upper pin 38 is swingably inserted into a through hole 7 e formed in the vertical plate 7 a of the support fitting 7. The periphery of the through hole 7e protrudes outward in the width direction of the chair, and is in contact with the inner surface of the link plate 35. A stopper hole 7f formed of a circular arc-shaped through hole of about 45 degrees centered on the through hole 7e from directly below the through hole 7e toward the front.
The lower pin 39 of the link plate 35 is movably inserted into the stopper hole 7f. Therefore, the link plate 35 swings around the upper pin 38, and the swing is performed within a range until the lower pin 39 contacts the front and rear edges of the stopper hole 7f.

As shown in FIG. 1, FIG. 2, FIG. 11, and FIG. 13, the lower pin 39 is connected to the gas spring 9 via the mounting bracket 42 inside each of the vertical plates 7a, 7a. . The front end of the gas spring 9 is swingably attached to a rotary shaft 41 supported by a shaft support hole 7 a at the front end of the support fitting 7.

The gas spring 9 is disposed between the vertical plates 7a, 7a of the support fitting 7, with the longitudinal direction being the longitudinal direction. A threaded portion 43 is formed at the rear of the gas spring 9, and a push pin 44 protrudes from an end surface of the threaded portion so that the set length of the gas spring can be changed. A mounting bracket 42 is screwed to the screw portion 43.

The gas spring 9 is expanded and contracted by the flow of a liquid inside the gas spring 9, and is switched between an unlocked state and a locked state when the push pin 44 comes and goes. When the push pin 44 is pushed in, the unlock state is established, and the gas spring 9 can expand and contract without generating a reaction force. In addition, push pin 4
When the protruding portion 4 is in a locked state, the length of the gas spring 9 under no load is set to an arbitrary length, and the gas spring 9 can expand and contract while generating a reaction force at this set length.

Therefore, when the occupant leans on the backrest 1, the back support rod 2, the back support rod support shaft 4, and the adapter member 31 integrated with the backrest 1 support the lever 61 at both ends. Rocked as That is, the front end of the lever 61 is swung about the upper pin 38 by the link plate 35, and the rear end of the lever 61 is swung about the rotation shaft 41 by the washer 8. At this time, since a downward weight is applied to the seat receiving member 8 via the seat portion 5, the seat receiving member 8 swings downward around the shaft support hole 8d at the front end. For this reason,
The bearing 60 and the adapter member 31 swing downward while moving downward. At the same time, the lever 61 is moved forward, so that the through hole 61b at the front end thereof is
Then, the gas spring 9 is pressed via the mounting bracket 42.

In the present embodiment, a mechanism for receiving a load by compressing the Gaussian spring 9 is not limited to this, but a mechanism for receiving a load by pulling the gas spring 9 may be used. In the present embodiment, the seat 5
Is 6 degrees, and the maximum tilt angle of the backrest 1 is 21 degrees. However, it is a matter of course that the angles are not limited to these angles.

As shown in FIGS. 11 and 13, an upper end of a push lever 46 is swingably mounted on the upper part of the mounting bracket 42. The center of the push lever 46 is moved by the gas spring 9
Push pin 44 can be pressed. A wire 48 is connected to a lower end of the push lever 46. The wire tube 49 of the wire 48 is fixed to the lower end of the mounting bracket 42. Therefore, as the gas spring 9 expands and contracts,
The fitting 42, the push lever 46, the wire 48, and the wire tube 49 are simultaneously moved. The other ends of the wire 48 and the wire tube 49 are connected to an operation lever (not shown). As this operation lever, a lever that pulls the wire 48 only when operated by a seated person is used.

Therefore, when the occupant leans on the backrest 1 while the occupant operates the operation lever and pushes the push pin 44 of the gas spring 9, the gas spring 9 is in an unlocked state. Rest 1 and seat 5
Is tilted without reaction force. When the operation lever is released at an arbitrary inclination angle, the push pin 44 projects and the gas spring 9 is locked, so that the positions of the backrest 1 and the seat 5 are locked in an inclined state. When the seated person applies a load to the backrest 1 in this state, the gas spring 9 is compressed, so that the backrest 1 receives a reaction force as if returning to the locked position. Thus, according to the present embodiment, the weight of the occupant is supported by the gas spring 9 in addition to the reaction force unit 33.
Can be reduced.

As the operation lever, in addition to the one in which the lever is released when the hand is released as in this embodiment, the one in which the lever can be switched between a pulled state and a non-pulled state may be used. it can. In this case, even when the occupant releases his / her hand from the lever, the backrest 1 and the seat 5 can be tilted without any reaction force. For example, before seating, the lever is fixed in a state where the lever is pulled, and after the user sits down and adjusts the angles of the backrest 1 and the seat part 5, the state is switched to a state where the lever is not pulled to switch the backrest 1 and the seat part. Position 5 can be locked.

Further, since the gas spring 9 expands and contracts due to the flow of a liquid inside the gas spring 9, the flow resistance increases with respect to a load acting suddenly, and the length of the gas spring 9 changes substantially. do not do. For this reason, even if a vertical shock load acts on the seat portion 5 when the seated person is suddenly seated, the seat portion 5 and the backrest 1 are maintained at a fixed position without tilting. Therefore, the backrest 1 does not hit the back of the seated person due to the recoil, and the feeling of use is improved.

On the other hand, the length of the gas spring 9 changes with a slow load. For this reason, the backrest 1 and the seat portion 5 are inclined by slowly applying a load to the backrest 1 after the occupant sits down suddenly.

In the present embodiment, the shaft holding portion 29 is constituted by the bearing 60 and the adapter member 31 and the seat receiving portion 3 is structured such that the backrest 1 and the seat portion 5 tilt in conjunction with each other. The structure is not limited to this, and the seat 5 may be fixed and only the backrest 1 can be tilted. Further, in the present embodiment, the backrest 1 is made swingable by making the back support rod support shaft 4 rotatable.
Or the receiving portion 63 having the locking portion 63a of the adapter member 31 and the wall surface 63b on the bearing 60.
The backrest 1 is formed directly by forming
May not be able to swing. In this case, there is no need to provide a backrest swinging mechanism in the seat receiving portion 3, so that the structure can be simplified.

On the other hand, as shown in FIGS. 1, 2 and 14,
The pin 38 on the upper side of the link plate 35 is
e protrudes inward from e. An elevating lever 50 is swingably attached to the protruding portion. The rear end of the lifting lever 50 can swing to press the gas spring at the upper end of the pillar 6. A wire 51 for pulling the front end forward is engaged with the front end of the lifting lever 50. Further, the wire tube 52 of the wire 51
Is a wire support 5 screwed to one of the vertical plates 7a.
3 supported. By operating an operation lever (not shown) attached to the other end of the wire 51, the gas spring of the pillar 6 can be extended and contracted.

Next, the backrest 1 will be described. As shown in FIG. 6, the backrest 1 includes an inner shell 10 and an outer shell 11 that covers the rear side of the inner shell 10.
And a backrest elevating mechanism 13. A support plate 14 for the back support rods 2 is attached to a lower portion of the rear surface of the outer shell 11. A cushion made of sponge, urethane, or the like is attached to the front side of the inner shell 10. An upholstery made of cloth or the like is stretched on the front side of the cushion so as to cover the cushion. Assembling of the inner shell 10 and the outer shell 11
Engagement hole 10a of inner shell 10 and outer shell 1
This is achieved by engaging with the first engaging claw 11a. However, the present invention is not limited to this, and it may be assembled with screws such as bolts.

The front surface of the support plate 14 of the back support rods 2, 2 has a guide groove 14a formed in a vertically long shape on the left and right sides. A slider 27 is screwed to the rear surface of the outer shell 11. The slider 27 is fitted in the guide groove 14a of the support plate 14. Therefore, the outer shell 11 and the slider 27 are slidable vertically with respect to the support plate 14 and the back support rods 2.

The backrest elevating / lowering mechanism 13 includes the outer shell 1
An operating lever 16 slidable with respect to 1, a rotation center pin 17, a return spring 18, a left lock arm 22 and a right lock arm 21, and lock pins 28, 28 are provided. The operation lever 16 includes a through hole 16a at the center, a stopper 16b at the upper end, and a knob mounting portion 16c at the lower end, and is formed on a side slope between the stopper 16b and the knob mounting portion 16c. On the other hand, in the lower part of the front surface of the outer shell 11, two pairs of support protrusions 11b, 11b are provided.
1 and is formed by integral molding. Support projection 1 for each pair
A guide groove whose longitudinal direction is the vertical direction is formed on the facing surfaces of 1b and 11b. The side surface of the operation lever 16 having the above-described slope is sandwiched between the guide grooves. Thus, the operation lever 16 is supported slidably in the up-down direction with respect to the outer shell 11. An operation knob 25 is fitted to the knob mounting portion 16c by fitting.

A rotation center pin 17 is engaged with the through hole 16a of the operation lever 16. The rotation center pin 17 is integrated with the right lock arm 21. This rotation center pin 1
7, a through hole of the left lock arm 22 is rotatably fitted. Each lock arm 21 and 22 has a lock pin 2
The return spring 18 is urged so that the upper and lower parts 8, 28 spread apart from each other.

The rear portions of the lock pins 28, 28 pass through the horizontally long through holes 11 c, 11 c formed in the outer shell 11, and lock grooves 23 a or communication grooves 23 of the support plate 14.
b. Each through hole 15b of the slide plate 15,
15b has a horizontally long shape. Lock groove 23a,
, 23a are a plurality of horizontally elongated grooves formed in pairs in the left and right direction along the vertical direction. Each communication groove 23b, 23
b has a shape that communicates the inside of each pair of lock grooves 23a, 23a in the vertical direction.

When the operation lever 16 is not depressed, the lock arms 21 and 22 are opened.
, 23a. In this state, the backrest 1 is fixed to the back support rod 2. When the operation knob 25 at the lower end of the operation lever 16 is pushed up, the rotation center pin 17
Is pushed up. Thereby, each lock pin 28, 2
8 is guided by the through holes 11c, 11c of the outer shell 11 and moves inward so as to reduce the distance between them.
Thereby, each lock pin 28, 28 moves from the lock groove 23a, 23a to the communication groove 23b, 23b and becomes slidable in the vertical direction. Thus, the outer shell 11 can be moved up and down with respect to the support plate 14, so that the vertical position of the backrest 1 can be adjusted. Then, the user slides the backrest 1 with the operation lever 16 pushed in. When the operation lever 16 is released, each lock pin 2 is actuated by the action of the return spring 18.
8, 28 move in the direction away from each other and engage with any of the lock grooves 23a,..., 23a. Thereby, the position of the backrest 1 is set.

Therefore, in this embodiment, since the backrest elevating mechanism 13 is provided on the backrest 1, the position of the backrest 1 with respect to the seat receiving portion 3 can be adjusted. However, the present invention is not limited to this, and the backrest 1 and the back support rod 2 may be directly coupled without providing the backrest elevating mechanism 13. In this case, the backrest 1
Can be simplified.

According to the chair configured as described above, the backrest 1 and the seat portion 5 are assembled to the seat receiving portion 3 as follows.

First, the rotating shaft portion 32 of the adapter member 31 is inserted into the bearing 60 from the axial direction, and the adapter member 31 is mounted on the bearing 60 of the seat receiving portion 3. Next, the back support rod 4 is connected to the opening 30 of the bearing 29 and the opening 6 of the adapter member 31.
2 and is accommodated in the accommodating portion 63 of the adapter member 31. Then, as shown in FIG. 3 or FIG. 10, the back support rod 4 is rotated clockwise until it comes into contact with the wall surface 63b of the housing portion 63. Further, the back support arm 45 and the lever portion 61 are connected and fastened by a set screw 46. Thus, the attachment of the back support rod 4 is completed. Therefore, the back support rod 4 is connected to the bearings 60 and the openings 30 and 6 of the adapter member 31.
The seat support 3 and the back support rod 2 are engaged and connected only by being inserted into the bearing, that is, the housing portion 63 from the bearing support 2. The backrest 1 of a different design can be freely attached to the part 3. In other words, the backrest 1 and the back support rod 2 of a plurality of other designs can be attached to the seat portion 5 and the seat receiving portion 3 of a certain design. Moreover, since the back support rod arm 45 and the lever 61 are connected, the back support rod 4 does not come off the adapter member 31, so that the backrest 1 does not come off the seat receiving section 3.

The rotation shaft 3 of the adapter member 31
2 can rotate with respect to the bearing 60 of the seat receiving portion 3, so that the backrest 1 and the back support rod 2 can be tilted with respect to the seat receiving portion 3.
Further, since the seat bracket 8 supporting the seat 5 is integral with the bearing 60 and is swingably connected to the adapter member 31, the rear portion of the seat 5 also moves up and down as the back support rod 2 tilts. And tilt.

Next, a second embodiment of the chair of the present invention will be described. As shown in FIG. 20, the backrest 1 according to the second embodiment includes an inner shell 10 and an outer shell 11.
And a front cover 12 that covers a lower portion of the front surface of the outer shell 11, and a backrest elevating mechanism 13. Since the inner shell 10, the outer shell 11, and the backrest elevating mechanism 13 of the components of the backrest 1 of the present embodiment are different in shape from those of the above-described first embodiment, they are the same. The same reference numerals are used in the figures, and the description is omitted.

In the front portion of the back support rods 2 and 2 of the present embodiment, a truncated cone-shaped back support rod support cone 2a having the left-right direction as the axial direction.
Are formed. Between the back support rod support cones 2a, 2a, the back support rods 4, 4 and the connecting shaft 26 are coaxially integrated. Further, a back support rod arm 45 is formed at a connection portion between the back support rod support cone 2 a and the back support rod support shaft 4.
The back support rods 2 and 2 are formed in a straight line while decreasing the interval toward the rear. At the rear end of the back support rods 2, 2, a support plate 14 substantially perpendicular to the back support rods 2, 2 is attached. The back support rods 2, 2, the support plate 14, the back support rods 4, 4, and the connection shaft 26 are integrally formed by die casting of zinc or an aluminum alloy. However, the present invention is not limited to this, and each component may be assembled as a separate member by press fitting, welding, or the like.

The backrest elevating mechanism 13 of the backrest 1 is attached to the support plate 14. The support plate 14 and the backrest elevating mechanism 13 are covered and hidden by the front cover 12. At the bottom of the front cover 12, a vertically long notch 12
a and 12a are formed. The back support rod 2 protrudes forward from the front surface of the backrest 1 through the notches 12a.

The backrest elevating mechanism 13 of this embodiment includes a slide plate 15 which can be raised and lowered with respect to the support plate 14, an operation lever 16, a rotation center pin 17, a return spring 18, a left lock arm 22, and a right lock arm 22. Lock arm 21, lock pin 28,
28. The left and right edges of the slide plate 15 are bent inward to form guides 15a, 15a. Guide rails 19, 1 are provided on the respective guide portions 15a, 15a.
9 is attached. The left and right edges of the support plate 14 are supported by the guide rails 19, 19. This allows
The slide plate 15 is guided vertically along the support plate 14. The slide plate 15 is screwed to the lower portion of the outer shell 11 with four bolts 20.

The front portions of the lock pins 28, 28 are inserted through the through holes 15b, 15b of the slide plate 15 into the lock grooves 23a or the communication grooves 23b of the support plate 14.
Each through hole 15b, 15b of the slide plate 15 has a horizontally long shape. The shape of each lock groove 23a and communication groove 23b is the same as that of the first embodiment. Further, on the rear side of the outer shell 11, these through holes 11c, 11c are provided.
Small covers 24, 24 for covering the tips of bolts 20 to which the slide plate 15 is fixed are attached.

According to this embodiment, the back support rods 2 can be attached to the seat receiving portion 3 by the back support rod 4 in the same manner as in the first embodiment.

Therefore, according to each of the first and second embodiments, the backrest 1 having a completely different design can be mounted while sharing the seat receiving portion 3. That is, in the chairs shown in these embodiments, a plurality of backrests 1 and back support rods 2 having different designs are attached to the seat receiving portion 3 while sharing the pillar 6, the seat receiving portion 3, and the seat portion 5. be able to. For this reason, when manufacturing chairs of a plurality of designs, it is possible to reduce the number of types of designs of the seat portion 3, thereby improving production efficiency and reducing component costs.

The above embodiment is an example of a preferred embodiment of the present invention, but the present invention is not limited to this, and various modifications can be made without departing from the gist of the present invention. For example, in the present embodiment, the case where the chair is applied to the office swivel chair has been described, but the chair may be applied to other types of chairs. Further, in the present embodiment, the chair in which the tilting of the backrest 1 and the seat 5 interlock is described. However, the present invention is not limited thereto, and a chair in which only the backrest 1 tilts or a chair in which only the seat 5 tilts may be used. Of course it does not matter.

Further, in the present embodiment, the backrest 1 and the back support rod 2 are attached to the seat receiving portion 3 by coupling the back support rod support shaft 4 and the shaft holding portion 29. However, the present invention is not limited to this. Needless to say, other back support rod mounting structures may be used. For example, in the present embodiment, a structure in which the two back support rods are connected by the back support rod support shaft 4 is used.
A structure in which the back support rod 4 is mounted so as to protrude left and right from the back support rod, that is, an inverted T-shaped structure may be adopted. Further, in the present embodiment, the shaft holding portion 29 is configured by the bearing 60 and the adapter member 31, but is not limited thereto, and the bearing 60 is provided with the accommodating portion 63 and the opening 62 of the adapter member 31. Thus, the shaft holding portion 29 may be configured to directly receive the back support rod 4.
In this case, the size of the opening 30 of the bearing 29 is formed smaller than the long diameter portion L1 of the back support rod 4 and wider than the short diameter portion L2.

[0094]

As is apparent from the above description, the invention according to claim 1 is characterized in that a seat receiving member attached to a seat portion and a leg-side fixing device attached to a leg portion for swingably supporting the seat receiving member. In a chair provided with a seat receiving portion that supports a seat portion in a tiltable manner with a member, the chair is swingably interposed between the seat receiving member and a leg-side fixing member, and is returned to an original position with respect to the seat receiving member by expansion and contraction. A reaction force unit that applies a reaction force, and a reaction force adjustment mechanism that swings the reaction force unit without changing the amount of expansion and contraction to change the inclination with respect to the seat receiving member and maintain the inclined state. Therefore, when the reaction unit is tilted, the amount of expansion and contraction of the reaction unit with respect to the tilt of the seat is changed, and the reaction force with respect to the tilt of the seat can be adjusted. Since the reaction force unit is tilted without changing the amount of expansion and contraction, the reaction force of the seat can be adjusted by the reaction force adjustment mechanism with a constant light force. Thereby, even a person such as a woman with a weak grip strength can easily perform the work of adjusting the reaction force.

According to a second aspect of the present invention, there is provided a chair in which a back support rod for supporting a backrest is swingably supported by a seat receiving portion attached to a leg portion so that the backrest can be inclined. A reaction force unit that is swingably interposed between the support rod and the seat receiving portion and provides a reaction force for returning the seat receiving portion to the original position by expansion and contraction; And a reaction force adjusting mechanism that changes the tilt with respect to the back support rod and maintains the tilted state, so that the reaction unit is tilted to prevent the backrest from tilting. By changing the amount of expansion and contraction of the force unit, the reaction force against the tilt of the backrest can be adjusted. And
Since the reaction force unit is tilted without changing the amount of expansion and contraction, even a person such as a woman with weak grip strength can easily perform the operation of adjusting the reaction force.

Further, the invention according to claim 3 is a seat receiving member attached to the seat portion, a leg side fixing member attached to the leg portion for swingably supporting the seat receiving member, a seat receiving member or the leg side fixing member. A chair that has a back support rod that is swingably supported by the fixed member and that supports a backrest that tilts in conjunction with the tilt of the seat receiving member, and that tilts the backrest in conjunction with the tilt of the seat. , Between the seat receiving member and the leg-side fixing member or between the back support rod and the seat receiving member or the leg-side fixing member so as to be able to swing and return to the original position with respect to the seat receiving member or the back supporting rod by expansion and contraction. And a reaction force adjustment unit that swings the reaction force unit without changing the amount of expansion and contraction to change the inclination with respect to the seat receiving member or the back support rod and maintain the inclined state. Mechanism, so that the reaction unit is tilted Rukoto by, is stretchable amount of the reaction force unit changes to the seat and the backrest tilt, it is possible to adjust the reaction force against the seat and backrest tilting of. The reaction force unit is tilted without changing the amount of expansion and contraction, so that even a person such as a woman with a weak grip strength can easily perform the reaction force adjustment operation.

Further, the invention according to claim 4 is a seat receiving member attached to the seat, a leg-side fixing member attached to the leg for swingably supporting the seat receiving member, a seat receiving member or the leg-side. A back support rod that is supported by the fixed member so as to be swingable and supports a backrest that tilts in conjunction with the tilt of the seat receiving member,
In a chair in which the backrest is tilted in conjunction with the tilt of the seat, an unlocked state that can freely expand and contract with no reaction force, and a seat receiving member that can expand and contract while generating a reaction force at an arbitrarily set position and A gas spring that can be switched to a locked state in which the backrest returns to the locked position and applies a reaction force is interposed between the back support rod and the seat receiving member or the leg-side fixing member, and is expanded and contracted in accordance with the tilting thereof. Therefore, the backrest and the seat can be locked at an arbitrary tilt angle. For this reason, for example, when the backrest is greatly inclined and used like an easy chair, the occupant can maintain the inclined state without putting weight on the backrest, thereby improving the usability.

Further, even if a seated person is seated vigorously and a vertical impact load is applied to the seat, the seat and the backrest do not tilt.
Therefore, the backrest does not hit the back of the seated person due to the recoil, and does not give any discomfort. Only when a slow load is applied, the gas spring expands and contracts, and the seat and the backrest are inclined. Further, since the gas spring can be in a free state in which the drag is reduced to zero, a so-called free rocking state in which the backrest and the seat can freely tilt without receiving a reaction force can be achieved.

Further, the invention according to claim 5 includes a seat receiving member attached to the seat, a leg-side fixing member attached to the leg to swingably support the seat receiving member, and a seat receiving member or the leg side. A back support rod that supports a backrest that is swingably supported by the fixed member and that tilts in conjunction with the tilt of the seat receiving member,
In a chair in which the backrest is inclined in conjunction with the inclination of the seat portion, the backrest is tiltably interposed between the seat receiving member and the leg-side fixing member or between the back support rod and the seat receiving member or the leg-side fixing member. A reaction force unit that applies a reaction force to the seat receiving member or the back support rod to return to the original position by expansion and contraction, and swings the reaction force unit without changing the amount of expansion and contraction to the seat reception member or the back support rod. Equipped with a reaction force adjustment mechanism that changes the tilt and maintains the tilt state, and can be freely expanded and contracted with no reaction force, and expands and contracts while generating a reaction force at an arbitrary set position A gas spring, which can be switched to a locked state in which the seat receiving member and the backrest return to the locked position to apply a reaction force, is interposed between the back support rod and the seat receiving member or the leg side fixing member, and these tilt. To expand and contract with Therefore, even a person such as a woman with a weak grip can easily adjust the reaction force of the seat and the backrest with a constant light force, and lock the backrest and the seat at an arbitrary tilt angle. Even if a seated person is seated vigorously and a vertical impact load is applied to the seat portion, the backrest does not hit the seated back due to recoil.

Further, in the chair according to the sixth aspect, the reaction force unit or the reaction force adjustment mechanism is provided with a display member interlocking with the tilting of the reaction force unit, and at least covers the reaction force adjustment mechanism and the reaction force unit. In addition to providing the cover, the cover is provided with a display portion from which the display member is exposed, so that the occupant can objectively recognize the reaction force of the seat portion and the backrest. For this reason, for example, even when there are a plurality of users, each user can set the magnitude of the reaction force to a predetermined size of his / her preference, and can obtain the same feeling of use every time. it can.

The chair according to the seventh aspect of the present invention includes a back support rod integrated with the back support rod and extending in the width direction of the chair, and a back support rod formed on the seat receiving member or the leg-side fixing member. A shaft holding portion that is fitted and supported, and at least a portion of the back support rod that fits with the shaft holding portion has a non-circular cross section having a long diameter portion and a short diameter portion, and the shaft holding portion has Accommodates a radial opening wider than the short diameter part of the back support rod and narrower than the long diameter part, and accommodates the back support rod inserted from the opening and fixed at a position shifted circumferentially from the opening The back support rod support shaft is inserted into the housing portion of the shaft holding portion from the opening and rotated to engage with the support portion, so that the shape and dimensions of the back support rod support shaft are reduced. The backrest of a different design can be attached to the seat receiving part by the common use. That is, the seat receiving portion, the seat portion, and the leg portion are shared, and the backrests and the back support rods of various designs can be attached to the shared components. Therefore, the production efficiency can be improved and the production cost of the chair can be reduced. In addition, since the back support rod can be undetachably engaged only by inserting the back support rod into the bearing through the opening and then rotating, the mounting of the back support rod to the seat receiving part can be completed very easily with one touch. obtain.

Further, in the chair according to the eighth aspect, the shaft holding portion is constituted by a bearing having an opening through which the spine support shaft passes radially, and an adapter member rotatable inside the bearing. An accommodating portion that holds the spine support shaft non-rotatably on the member, a radial opening wider than the short diameter portion of the spine support shaft and narrower than the long diameter portion, and a rotation rotatably supported by the bearing. Since the shaft portion and the fixing portion fixed to the back support rod side are provided, the adapter member, the back support rod support shaft, the back support rod, and the backrest can be integrally tilted. For this reason,
Even with a chair in which the backrest can be tilted, a backrest of a different design can be attached to the seat receiving portion by sharing the shape and dimensions of the back support rod support shaft.

Further, in the chair according to the ninth aspect, in the accommodating portion of the adapter member, when the spine support shaft rotates, the spine support shaft is caught and cannot be passed through the opening of the adapter member. Is formed, and the fixing portion of the adapter member is fixed to the back support rod side in a state where the back support rod is hooked on the locking portion, so that the back support is tilted regardless of the tilting state of the backrest. The rod support shaft does not come off the adapter member. For this reason, when the chair is lifted with the backrest, the backrest is prevented from coming off the seat receiving portion.

[Brief description of the drawings]

FIG. 1 is a side view of the vicinity of a seat receiving portion showing a first embodiment of a chair of the present invention.

FIG. 2 is a bottom view around a seat receiving portion of the chair.

FIG. 3 is a side view of the vicinity of a spine support shaft.

FIG. 4 is an exploded view showing a connecting portion between the shaft holding portion and the back support rod support shaft.

FIG. 5 is a rear view showing the entire back support rod.

FIG. 6 is an exploded view showing a backrest and a back support rod.

FIG. 7 is a sectional view showing a state cut along the line VII-VII in FIG. 3;

FIG. 8 is a plan view showing a connecting portion between the shaft holding portion and the back support rod.

FIG. 9 is a cross-sectional view showing a state cut along line IX-IX in FIG. 3;

FIG. 10 is a side view showing each part of the adapter member.

FIG. 11 is a cross-sectional view showing a state cut along the line XI-XI of FIG. 1;

FIG. 12 is a sectional view showing a state cut along the line XII-XII in FIG. 1;

FIG. 13 is a longitudinal sectional view of a support fitting showing a mounting structure of a gas spring.

FIG. 14 is a side view of a support fitting showing a mounting structure of a lifting lever.

FIG. 15 is a side view of the support bracket showing the reaction force unit and the reaction force adjustment mechanism when the reaction force is at a maximum.

FIG. 16 is a side view of the support bracket showing the reaction force unit and the reaction force adjustment mechanism when the reaction force is at a minimum.

FIG. 17 is a side view of a distal end portion of a support fitting showing a vertical groove.

FIG. 18 is a bottom view of the distal end portion of the support fitting showing the reaction force adjusting mechanism.

FIG. 19 is a side view of the cover.

FIG. 20 is an exploded perspective view showing a second embodiment of a backrest and a back support rod.

FIG. 21 is a side view showing a seat support mechanism of a conventional chair.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 backrest 2 back support rod 3 seat support 4 back support rod support shaft 5 seat 6 pillar (leg) 7 support bracket (leg-side fixing member) 8 seat support (seat support member) 9 gas spring 29 shaft Holding part 30 Opening part 31 Adapter member forming shaft holding part 29 32 Rotating shaft part 33 Reaction force unit 54 Reaction force adjusting mechanism 60 Bearing forming shaft holding part 29 61 Lever part (fixed part) 62 Opening part 63 Housing part 63a Locking part 75 Cover 75a Display window (display part) 76 Display pin (display member) L1 Long diameter part L2 Short diameter part

Claims (9)

(57) [Claims] 1. A seat receiving portion that is attached to a seat portion and a leg-side fixing member that is attached to a leg portion and that supports the seat receiving member so as to be able to swing, the seat receiving portion that tiltably supports the seat portion. A chair comprising: a reaction force unit that is swingably interposed between the seat receiving member and the leg-side fixing member and applies a reaction force for returning the seat receiving member to the original position by expansion and contraction; A chair comprising: a reaction force adjusting mechanism that swings a reaction force unit without changing its expansion / contraction amount to change the inclination with respect to the seat receiving member and maintains the inclination state. 2. A chair in which a back support rod for supporting a backrest is swingably supported by a seat receiving portion attached to a leg so that the backrest can be tilted. A reaction unit that is swingably interposed between the receiving unit and the reaction unit that applies a reaction force to the seat receiving unit to return to the original position by expansion and contraction, and swings the reaction unit without changing the amount of expansion and contraction. And a reaction force adjusting mechanism for changing the inclination with respect to the back support rod and maintaining the inclination state. 3. A seat receiving member attached to a seat portion, a leg-side fixing member attached to a leg portion for swingably supporting the seat receiving member, and a swinging motion of the seat receiving member or the leg-side fixing member. A back support rod that is movably supported and supports a backrest that tilts in conjunction with the tilting of the seat receiving member, and the chair tilts the backrest in conjunction with the tilt of the seat. The seat receiving member or the back support rod is interposed between the seat receiving member and the leg-side fixing member or between the back support rod and the seat receiving member or the leg-side fixing member so as to be swingable. A reaction force unit that applies a reaction force that returns to the original position, and swings the reaction force unit without changing its expansion / contraction amount to change the inclination with respect to the seat receiving member or the back support rod, and A reaction force adjustment mechanism to maintain the tilted state. Chair featuring. 4. A seat receiving member attached to a seat portion, a leg side fixing member attached to a leg portion for swingably supporting the seat receiving member, and a swinging motion of the seat receiving member or the leg side fixing member. A back support rod that is movably supported and supports a backrest that tilts in conjunction with the tilting of the seat receiving member, and the chair tilts the backrest in conjunction with the tilt of the seat. An unlocked state that can freely expand and contract with no reaction force, and a lock that applies a reaction force that enables expansion and contraction while generating a reaction force at an arbitrarily set position, so that the seat receiving member and the backrest return to the lock position. A chair, wherein a gas spring which can be switched to a state is interposed between the back support rod and the seat receiving member or the leg side fixing member, and is expanded and contracted in accordance with the tilt of the chair. 5. A seat receiving member attached to a seat portion, a leg side fixing member attached to a leg portion for swingably supporting the seat receiving member, and a swinging motion of the seat receiving member or the leg side fixing member. A back support rod that is movably supported and supports a backrest that tilts in conjunction with the tilting of the seat receiving member, and the chair tilts the backrest in conjunction with the tilt of the seat. The seat receiving member or the back support rod is interposed between the seat receiving member and the leg-side fixing member or between the back support rod and the seat receiving member or the leg-side fixing member so as to be swingable. A reaction force unit that applies a reaction force that returns to the original position, and swings the reaction force unit without changing its expansion / contraction amount to change the inclination with respect to the seat receiving member or the back support rod, and With a reaction force adjustment mechanism to maintain the tilt An unlocked state in which it can freely expand and contract with no reaction force, and expands and contracts while generating a reaction force at an arbitrarily set position to provide a reaction force for returning the seat receiving member and the backrest to the lock position. A chair characterized in that a gas spring that can be switched to a locked state is interposed between the back support rod and the seat receiving member or the leg-side fixing member, and is expanded and contracted in accordance with the tilt of these. 6. The reaction force unit or the reaction force adjustment mechanism is provided with a display member that is interlocked with the tilt of the reaction force unit, and a cover that covers at least the reaction force adjustment mechanism and the reaction force unit. 4. The display according to claim 1, wherein the cover is provided with a display unit on which the display member is exposed.
Chair described in. 7. A back support rod support shaft that is integrated with the back support rod and extends in the chair width direction, and the back support rod support shaft formed on the seat receiving member or the leg-side fixing member is fitted to the back support rod support shaft. And a shaft holding portion for supporting the back support rod, and at least a portion of the back support rod supporting shaft fitted to the shaft holding portion has a non-circular cross section having a long diameter portion and a short diameter portion, and the shaft holding portion has The back support rod accommodates a radial opening wider than the short diameter part and narrower than the long diameter part and the back support rod inserted from the opening and is displaced in the circumferential direction from the opening. 7. An accommodation section fixed at a position, wherein the back support rod is inserted into the accommodation section of the shaft holding section from the opening and rotated to engage the back support rod. Chair according to any of the above. 8. The shaft holding portion includes a bearing having an opening through which the back support rod is passed in a radial direction, and an adapter member rotatable inside the bearing. An accommodating portion for holding the supporting rod support shaft in a non-rotatable manner, a radial opening wider than a shorter diameter portion of the back supporting rod supporting shaft and smaller than a longer diameter portion, and a rotating shaft rotatably supported by the bearing The chair according to claim 7, further comprising a fixing portion fixed to the back support rod side. 9. A locking portion is formed in the accommodating portion of the adapter member so that when the spine support shaft rotates, the spine support shaft is caught and cannot pass through the opening of the adapter member. 9. The chair according to claim 8, wherein the fixing portion of the adapter member is fixed to the back support rod side while the back support rod support shaft is hooked on the locking portion.