JP2003079472A - Rocking chair and its base - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve correspondence to a difference in height concerning users by reducing the lowest height of a seat when a kick spring is used as a spring for supporting the backward inclination of each rocking frame. SOLUTION: The base 7 fixed to the upper end of a leg supporter 1 consisting of a gas cylinder is formed to be a projected shape when viewing it from one plane where the rear part is a narrow width part 7b and the front part is a wide width part 7a. The rocking frame 11 with the attached seat back therein is connected to the wide width part 7a with a second axis 12. The kick spring 14 where a load is added in a coil winding direction is fitted to the second axis 12 and a load receiving part 14a for the kick spring 14 is arranged at the outside of the narrow width part 7b in the base 7. The left and right rocking frames 11 are connected with a third axis 13 for synchronizing the seat with the seat back and the third axis 13 is supported by the load receiving part 14a of the kick spring 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rocking chair and its base.

[0002]

2. Description of the Related Art Generally, a rocking chair has a structure in which a swing frame to which a backrest is attached is tiltably connected to a base fixed to the upper ends of leg columns, and a back tilt of the swing frame is supported by a spring. There is.

In this case, the base is often in the shape of a box having a substantially rectangular shape in plan view with an upward opening, and a spring and other members are arranged therein. As the leg support, a gas cylinder is generally used so that the height of the seat can be adjusted.

Further, as the spring, there are a case where a compression coil spring is used and a case where a kick spring in which one end of a coiled wire material is extended radially outward to form a load receiving portion is used. There is.

When using compression coil springs,
Since it is located on the front side of the center of rotation of the swing frame in the base, when a seated person leans against the backrest, the moment acting on the swing frame causes a large load on the compression coil spring. Tends to work. This tendency is particularly large in the case of a synchro type chair in which the seat is tilted backward (and / or retracted) in conjunction with the backrest.

On the other hand, when using a kick spring, generally, the kick spring is fitted on the shaft which is the center of rotation of the swing frame, and its load receiving portion extends rearward. Therefore, the swing frame is supported by the load receiving portion of the kick spring behind the center of rotation thereof, which has the advantage of suppressing the load on the spring.

[0007]

By the way, since the height of a person using a chair varies, a gas cylinder is used as a pedestal so that the height of the seat can be adjusted. Since there is a limit to the expansion and contraction stroke, it is difficult to handle people of all heights with just a gas cylinder.

In this case, a person with a high height can cope with it by stacking a cushion on the seat, but there is no method for a person with a short height who feels that even if the seat is lowered to the minimum height.

Therefore, in order to accommodate a wide range of height differences among users, it is preferable to set the minimum height of the seat as low as possible in accordance with a person with a short height.

However, for example, in the case of a chair using a kick spring as a spring for supporting the swing frame, the load receiving portion is arranged at a high distance from the base in order to prevent the load receiving portion from interfering with the base during rocking. Therefore, there is a limit to reducing the distance from the base to the upper surface of the seat, and it is difficult to reduce the minimum height of the seat.

In particular, in the case of a synchro chair in which the seat is tilted backward in conjunction with the backrest, a space for allowing the seat to be tilted backward is required, and it is difficult to lower the minimum height of the seat.

The present invention has as its main object to improve the present situation.

[0013]

The inventor of the present application has achieved the above-mentioned object by considering the relationship between the base and the spring. That is, according to the first aspect of the invention, the base provided on the upper ends of the leg columns and supporting the seat and the backrest is formed in a convex shape in a plan view having a narrowed rear portion.

The invention according to claim 2 relates to a chair, which comprises a base of an upward opening provided at the upper end of a leg support made of a gas cylinder, a seat arranged above the base, and left and right outer sides of the base. A swing frame that is arranged so as to extend rearward and is connected to the front-rear midway portion of the base so as to be able to tilt rearwardly, and a backrest that is arranged behind the seat and is attached to the swing frame. , A spring provided in the base for elastically supporting the rearward tilting of the swing frame.

Further, the base is formed in a substantially convex shape in a plan view in which a portion behind the connecting portion of the swing frame is a narrow portion and a front side thereof is a wide portion, and the narrow portion is formed. While being fixed to the leg support, the spring is a kick spring that forms a load receiving portion by extending one end of a wire wound in a coil shape to the outer side of the radius. The receiving portion is arranged so as to extend rearward between the narrow portion of the base and the swing frame in a plan view, and the rearward tilting of the left and right swing frames is supported by the load receiving portion of the kick spring.

According to the invention of claim 3, in claim 2,
A portion of the left / right swing frame that is behind the center of rotation is connected to the swing frame by a shaft for synchronizing the seat, and the shaft for synchronizing the seat is the load receiving portion of the kick spring. It is supported.

[0017]

According to the present invention, by using the kick spring as claimed in claim 2, since the load receiving portion of the kick spring can be released to the outside of the narrow portion of the base during rocking, the kick spring can be released. It is possible to lower the height of the load receiving portion at the position without interfering with the base during locking.

As a result, the seat is lowered as a whole,
The height of the seat at the lower limit of the descent can be reduced. In particular,
It is suitable to apply to a synchro type chair as described in claim 3.

Further, the invention of claim 1 can be applied to a chair using a coil spring, but in this case, there is an advantage that the flat area of the base can be reduced to save the material cost.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment in which the present invention is applied to a swivel chair with casters will be described with reference to the drawings.

1 is a front view, FIG. 2 is a right side view, FIG. 3 is a rear view, FIG. 4 is a separated perspective view seen from above, FIG. 5 is a separated perspective view seen from below, and FIG. 6 is a partial view. Fig. 7 is a perspective view, Fig. 7 is a vertical sectional side view in a non-locking state, Fig. 8 is a vertical sectional side view in a locking state, Fig. 9 is a schematic plan sectional view, and Fig. 10 is XX in Fig. 9.
FIG. 11 is a side sectional view in a non-locking state as seen from the view, and FIG. 11 is a side sectional view in a locking state similar to FIG.

.. Outline As shown in FIGS. 1 to 3, a chair includes legs 2 with casters having pedestals (gas cylinders) 1, a seat 3, an armrest device 4, a backrest 5, and a headrest device 6. ing.

A base 7 having an upward opening is fixed to the upper ends of the leg columns 1, and an intermediate member 8 spreading like a wing in a front view and the seat 3 are arranged above the base 7.

A pair of left and right bracket portions 8a and 8b are provided on the front portion and the rear portion of the intermediate member 8 so as to project downward. The front bracket portion 8a is connected to the base 7 by a first shaft 9 extending in the left-right direction. Has been done. Hole 1 in which the first shaft 9 fits into the base 7
Reference numeral 0 indicates an elongated hole in the front-rear longitudinal direction, and a bush made of synthetic resin is attached to the elongated hole 10.

A front portion of the swing frame 11 is connected to a substantially middle portion in the front and rear of the base 7 by a second shaft 12 extending in the left and right directions. A rear bracket 8b of the intermediate member 8 is provided in the middle of the swing frame 11 in the front-rear direction.
Are linked by. The third shaft 13 is fixed to the swing frame 11 with screws.

For example, as shown in FIGS. 4 and 6, the second shaft 1
Two left and right kick springs (kick springs) 14 are fitted from outside as an example of elastic supporting means in a portion of the member 2 located inside the base 7.

One end of the kick spring 14 is a load receiving portion 14a extending rearward, and the rear bracket 8b of the intermediate member 8 is in contact with the load receiving portion 14a from above. The other end of the kick spring 14 is supported by the receiving member 15 from above.

Therefore, the swing frame 11 is the kick spring 1
4, the intermediate member 8 and the seat 3 retreat while tilting backward in conjunction with the rearward tilting of the swing frame 11 (that is, the seat 3 synchronizes with the backrest 5). The initial elastic force of the kick spring 14 can be adjusted by the knob 16 engaged with the receiving member 15.

The swing frame 11 is formed in a substantially L shape in a side view having a rising portion 11a at the rear portion, and is manufactured by aluminum die casting or resin molding in this embodiment.

The backrest 5 includes a back frame (back strut) 18 attached to the swing frame 11 and the back frame 1.
A backrest plate (back inner member) 1 arranged on the front side of 9
9 and a back cover (back outer member) 20 arranged on the back side of the back frame 19. Back plate 1
A cushion 21 is stretched on the front surface of 9. The swing frame 11 and the back frame 19 may be integrally formed.

Although not shown, between the backrest plate 19 and the back cover 20, there is arranged a lumbar support device which pushes out a portion of the backrest plate 19 which mainly hits the waist of a seated person in a forward direction. A handle 22 having a shape that surrounds the back cover 20 from the back side in order to raise and lower the support device and push out the backrest plate 19.
Are arranged.

.. Base and Kick Spring As shown in FIGS. 4 to 9, the base 7 is formed in a box shape that opens upward, and a portion behind the second axis is a narrow portion 7 a, and a portion on the front side of the narrow portion 7 a. By forming the portion in the wide portion 7b, it has a convex shape in plan view as a whole,
Therefore, the boundary between the narrow portion 7a and the wide portion 7b is a stepped stepped portion 7c in plan view.

Then, the load receiving portion 14 of the kick spring 14
a extends rearward outside the narrow portion 7a of the base 7, and therefore, the load receiving portion 14a of the kick spring is
It can be pushed and bent below the upper surface of the base 7 without interfering with the narrow portion 7a of the base. Therefore, the intermediate member 8 can be arranged as low as possible, and the minimum height dimension of the seat 3 can be made as small as possible.

On the side plate of the narrow portion 7a of the base 7,
An upward notch 24 is formed so that the third shaft 13 can be lowered further.

As can be inferred from FIGS. 6 and 10, the spring bearing 15 is rotatably fitted to the second support shaft 8, and the spring bearing 15 is substantially U-shaped in a side view and extends forward. The load receiving portion 15a is formed. The other ends 14b of both kick springs 14 extend so as to hold the forwardly projecting portion 15a of the spring receiver 15 from below.

As shown in FIG. 6, a bolt receiver 25 is non-rotatably fitted in an upward recess of the forward projecting portion 15a of the spring receiver 15, and a bolt 26 is non-rotatably fitted into the bolt receiver 25 from above. waiting. The bolt 26 penetrates the base 7, and the knob 16 is screwed into the bolt 26 from below.

.. The intermediate support body and the seat intermediate support body 3 are made of synthetic resin (may be made of metal such as sheet metal), and the left and right edges are rail portions 28. A rear cover 27 that covers the rear surface of the base 7 is provided at the rear end of the intermediate member 8. Therefore, a person does not pinch his finger between the rear end of the intermediate member 8 and the base 7. Intermediate member 8
A large number of reinforcing ribs are formed on.

The seat 3 is composed of a seat plate (seat inner member) 29 made of synthetic resin and a cushion 30 stretched on its upper surface. As shown in FIG. 5 and FIG. A guide groove 31 that holds the rail portion 28 of the intermediate member 8 is formed in the. The fitting of the first rail 28 and the guide groove 31 allows the seat 3 to be moved back and forth relative to the intermediate member 8.

In this case, since the rail portion 28 is wrapped with the guide groove 31 from the outside, the seat plate 29 has the weight of the seated person.
Even when the rail is bent downward, the rail portion 28 and the guide groove 3
Since the seat plate 29 is self-assembled, the seat plate 29 can be prevented from coming off from the intermediate member 8.

A large number of slits 32 are formed in the seat plate 29 in order to facilitate its flexural deformation. Also, reinforcing ribs are formed.

The seat plate 29 may be directly connected to the base 7 and the swing frame 11 without providing the intermediate member 8. Further, the present invention is not limited to a synchro type chair,
It can also be applied to chairs in which only the backrest tilts backward.

.. Description of Other Members Reference numeral 34 shown in FIGS. 1 and 7 is a lower cover attached to the lower surface of the seat plate 29, and a pull hole 44 is formed at the front end thereof.

As shown in FIG. 7, a cam body 56 is rotatably fitted on the third support shaft 13. This cam body 56
By contacting the base 7, the tilting range of the backrest 5 can be switched to a plurality (four) of ranges.

Reference numeral 48 shown in FIGS. 4 and 6 is a link body fitted on the first shaft 9, which moves the seat plate 3 backward in conjunction with the backward movement of the first shaft 9. is there. That is,
The lower end of the link body 48 has a locking body 47 provided on the base 7.
The engaging pin 51, which is fitted in the inclined guide groove 50 formed in the upper part of the link body 48, penetrates the upper end of the link body 48, and the engaging groove 53 of the engaging bracket 54 provided on the lower surface of the seat plate 29.
Fit in.

Therefore, when the first shaft 9 retracts, the link body 48 rotates, and the rotation causes the seat plate 29 to move.
Retreat by a larger dimension. The intermediate member 8 has a relief hole 52 that allows the link body 48 to rotate.

A plurality of fitting grooves 53 are formed in the engagement bracket 54 of the seat plate 29, and the pull hole 44 of the lower cover 34 is formed.
When the front portion of the seat plate 29 is raised upward with a finger on the engaging pin 51, the engaging pin 51 can be fitted into the arbitrary fitting groove 53.
That is, the front-back position of the seat 3 can be adjusted.

[Brief description of drawings]

FIG. 1 is a front view of a chair according to an embodiment.

FIG. 2 is a right side view.

FIG. 3 is a rear view.

FIG. 4 is an exploded perspective view of an intermediate member and a base as viewed from above.

FIG. 5 is an exploded perspective view of a base, an intermediate member, and a seat plate as viewed from below.

FIG. 6 is an exploded perspective view of members arranged inside the base.

FIG. 7 is a vertical sectional side view in a non-locking state.

FIG. 8 is a vertical sectional side view in a locking state.

FIG. 9 is a schematic plan sectional view.

FIG. 10 is a side sectional view in a non-locking state as seen from the XX view of FIG. 9.

FIG. 11 is a side sectional view in a locking state similar to FIG.

[Simple explanation of symbols]

1 leg support (gas cylinder) Two legs 3 seats 5 backrest 7 base 7a narrow part 7b wide part 7c uneven part 8 Intermediate member 8b rear bracket 9 First axis 10 slots 12 Second axis 13 Third axis 14 Kick spring 14a Load receiving part

Claims (3)

[Claims] 1. A base for a rocking chair, which is a base provided on the upper end of a leg column to support a seat and a backrest, and which is formed in a convex shape in a plan view having a narrowed rear portion. 2. A base having an upward opening provided at an upper end of a leg column composed of a gas cylinder, a seat arranged above the base, and a shaft extending leftward and rightward on the left and right outer sides of the base. To support the tilting frame connected to the front and rear part of the base so as to be able to tilt rearwardly, the backrest arranged behind the seat and attached to the rocking frame, and to elastically support the tilting of the rocking frame to the rear. And a spring provided in the base, wherein the base is formed in a substantially convex shape in a plan view in which a portion behind the connecting portion of the swing frame is a narrow portion and a front side thereof is a wide portion. The narrow portion is fixed to the leg support, while the spring is a kick spring that extends one end of a coiled wire rod to the outside of the radius to form a load receiving portion. If this kick Is arranged so that the load receiving portion extends rearward between the narrow portion of the base and the swing frame in a plan view, and the load receiving portion of this kick spring supports the rear tilting of the left and right swing frames. I have a rocking chair. 3. A portion of the left / right swing frame that is behind the center of rotation is connected to the swing frame by a shaft for synchronizing the seat, and the shaft for synchronizing the seat is the kick. It is supported by the load receiving part of the spring,
The rocking chair according to claim 2.