The present invention relates to a chair with an armrest, and particularly relates to a chair with an armrest in which a rear part of a seat is lifted in an unused state, the seat guides a sitting by coming into contact with buttocks of a person seated and rotating to a nearly horizontal position with the buttocks when the person seated is sitting, and the rear part of the seat is lifted to assist in standing up when the person seated is standing up.
As this type of chair, there is a chair which rotatably supports a seat between an unused position which is inclined in a rear upward direction with respect to a lower part member of the chair, and a usage position which is horizontal or inclined in a rear downward direction, includes an impelling unit that impels the seat toward the unused position, and includes a backrest at a rear part of the seat (for example, see Patent Literature 1).
On the other hand, there is a chair in which an armrest is connected to a seat (for example, see Patent Literature 2).
Patent Literature 1: Japanese Laid-open Patent Publication No. 2010-104463
Patent Literature 2: Japanese Patent No. 3156115
It is desirable to provide an armrest to the chair in which a rear part of a seat rotates between an unused state and a usage state disclosed in Patent Literature 1. However, in a case where an armrest is attached to a seat as Patent Literature 2 in the chair of Patent Literature 1, when a person seated stands up from a state in which the person is seated and the armrest is put under a desk, the armrest moves upward due to an upward rotation of the rear part of the seat, and the armrest may come into contact with a top plate of the desk.
The present invention is conceived in view of the above problem, and an object of the invention is to provide a chair with an armrest capable of safely using the armrest when a rear part of a seat rotates.
According to the invention, the above problem is solved as below.
(1) It includes: a support base supported by a leg; a seat that is pivotally fixed to the support base using an axle extending in a left and right direction, a rear part of the seat being rotatable upward and downward; an impelling unit that is provided at the support base and impels the seat at the rear of the axle upward; and an armrest in which a lower part is connected to the support base, and an upper part stands upward from an exterior side of the seat.
In this configuration, a height of the armrest connected to the support base does not change even when the rear part of the seat rotates upward or downward. Accordingly, the armrest does not come into contact with a top plate of a desk and the like when a person seated stands up from the seat and thus, a chair may be safely used.
In the above (1), the support base has a shape that is spread forward in planar view and is inclined in a front upward in side view, and the armrest is connected to a lateral side in a front part of the support base.
In this configuration, a horizontal distance between a portion where a person seated puts his elbow in the armrest and a connection portion with respect to the support base of the armrest may be relatively shortened and thus, a bending moment applied to the connection portion with the support base of the armrest may be reduced when a load is applied to the armrest by the person seated. As such, it is possible to prevent the armrest from deviating from the support base. In addition, since the armrest is connected to the front part which is above a rear part of the support base, a vertical length of the armrest may be shortened when compared to a case where the armrest is connected to the rear part of the support base.
(3) In the above (2), the seat is pivotally fixed to a front part positioned above a rear part of the support base, and the armrest is connected to a portion behind the axle in the support base.
In this configuration, since the armrest may be connected to a portion separated from the axle of the support base, it is possible to enhance the strength by forming the connection portion using a thick member. In this way, it is possible to prevent the armrest from deviating from the support base.
In any one of the above (1) to (3), the armrest includes an armrest fulcrum that has an inward L shape in planar view, and an elbow pad member fixed to an upper end surface of the armrest fulcrum, and the armrest fulcrum passes from the support base to a lower part of the seat and stands upward from an exterior side of the seat.
In this configuration, since the armrest connected to the support base may be separated from a lower surface and a side surface of the seat, it is possible to prevent the armrest from disturbing a rotation of the seat.
(5) Fitting convex portions divided into two-pronged ends are provided to one of an attachment target portion of the chair that attaches the armrest positioned at a side of the seat and an attachment portion attached to the attachment target portion of the armrest, fitting concave portions divided into two-pronged ends are provided to the other one, a width between external surfaces in the fitting convex portions gradually decreases toward a tip of the fitting convex portions, a width between internal surfaces in the fitting concave portions gradually decreases toward the inside of the fitting convex portions, the pair of the fitting convex portions and a reentrant portion positioned between the pair of the fitting convex portions are fitted to the pair of the fitting concave portions and a protrusion positioned between the pair of the fitting concave portions, and the attachment portion and the attachment target portion are fastened by a fastening unit from a fitting direction of the fitting convex portions and the fitting concave portions.
In this configuration, since external surfaces of a pair of the fitting convex portions divided into two-pronged ends in one of the attachment target portion of the chair and the attachment portion of the armrest, and internal surfaces of a pair of the fitting concave portions divided into two-pronged ends in the other one are formed in tapered shapes inclined in the same direction, the fitting convex portions come into contact with the fitting concave portions on a large area. Accordingly, a backlash is not generated between the attachment portion of the armrest and the attachment target portion of the chair, and it is possible to reduce a shear stress generated in the attachment portion of the armrest when a load is applied to the armrest by a person seated.
(6) In the above (5), the attachment target portion of the chair is provided at a portion where a width of a component, whose width increases toward a front or a rear in planar view, is increased.
In this configuration, since a horizontal distance between the attachment portion and a portion where a load is applied by a person seated of an armrest positioned at a side of the seat may be shortened, it is possible to reduce a bending moment applied to the attachment portion of the armrest when a load is applied to the armrest by the person seated.
(7) In the above (5) or (6), a screw hole is provided from an apical surface of the protrusion positioned between the pair of the fitting concave portions toward a basal portion of the protrusion, a screw through hole is provided on a bottom surface of the reentrant portion positioned between the pair of the fitting convex portions, and a screw passing through the screw through hole is screwed to the screw hole, thereby fastening the attachment portion of the armrest to the attachment target portion of the chair.
In this configuration, it is possible to increase a length of the screw that fastens the attachment portion of the armrest and the attachment target portion of the chair, and it is possible to strengthen a fastening power by the screw.
(8) In the above (5), a guard portion that comes into contact with a neighboring portion of the attachment target portion in the chair is provided around the attachment portion in the armrest.
In this configuration, it is possible to prevent an interlocking force between the attachment portion of the armrest and the attachment target portion of the chair from being excessively large.
According to the present invention, since a height of an armrest connected to a support base does not change when a rear part of a seat rotates upward or downward, it is possible to safely use the armrest.
Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.
As illustrated in
The support base 5 forms a shallow dish of a triangular shape in planar view that is spread forward (see
As illustrated in
The seat 6 is normally impelled upward toward the unused position by an impelling unit 10.
As illustrated in
As illustrated in
During a downward rotation of the seat 6 from the unused position to the usage position (see
As illustrated in
As illustrated in
Herein, an example of an attachment structure of the armrest 14 (armrest fulcrum 15) in the chair with an armrest will be described with reference to
A pair of fitting convex portions 17a and 17b divided into two-pronged ends in the front and back direction are provided at the attachment portion 17 of the armrest 14, and a reentrant portion 17c is provided between the pair of fitting convex portions 17a and 17b. The fitting convex portions 17a and 17b form a quadrangular prism in which a tip narrows. A width between external surfaces of an upper and lower part, and a width between external surfaces of a front and rear part of the fitting convex portions 17a and 17b gradually decrease toward a tip of the fitting convex portions 17a and 17b, and the external surfaces of the upper and lower part and the external surfaces of the front and rear part are in tapered shapes.
A width between internal surfaces of a front and rear of the reentrant portion 17c positioned between the fitting convex portions 17a and 17b gradually decreases toward the inside, and the internal surfaces of the front and rear are in inverse tapered shapes opposite to the external surfaces of the fitting convex portions 17a and 17b. A reentrant of the reentrant portion 17c is shallower than a maximum protrusion size of the fitting convex portions 17a and 17b.
Widths between internal surfaces of a upper and lower part, and a front and rear of fitting concave portions 18a and 18b gradually decrease toward the inside of fitting concave portions 18a and 18b, and a width between external surfaces of a front and rear of a protrusion 22 positioned between the fitting concave portions 18a and 18b gradually decreases toward a tip of the protrusion 22. An external surface of the protrusion 22 is in an inverse tapered shape opposite to the internal surfaces of the fitting concave portions 18a and 18b.
As illustrated in
A lower surface in the attachment portion 17 of the armrest fulcrum 15 is provided with a concave portion 19, and a bottom surface of the concave portion 19 is provided with a screw through hole 20 that passes through the armrest fulcrum 15 to reach a bottom surface of the reentrant portion 17c. In addition, around the attachment portion 17, a guard portion 24 that comes into contact with a neighboring portion in the attachment target portion 18 of the support base 5 is provided.
When the attachment portion 17 of the armrest 14 is attached to the attachment target portion 18 of the support base 5, the pair of the fitting convex portions 17a and 17b, and the reentrant portion 17c of the armrest fulcrum 15 are fitted to the pair of the fitting concave portions 18a and 18b, and the protrusion 22 of the support base 5, and then a screw 21 passing through the screw through hole 20 from the concave portion 19 for spot facing of the armrest 14 is screwed to the screw hole 23 in the protrusion 22 of the support base 5, thereby fastening the attachment portion 17 and the attachment target portion 18 from a fitting direction of the fitting portions 17a and 17b and the fitting concave portions 18a and 18b.
In the chair with an armrest having the above configuration, the rear part of the seat 6 is raised upward by an added force of the impelling unit 10 in the unused state illustrated in
In addition, in the unused state of
In this state, when the person is seated, the seat 6 rotates to the usage position illustrated in
When the person seated pushes his back backward by leaning against the backrest 11 from a seated state illustrated in
When the person seated pulls his back forward, the backrest 11 is rotated forward about the spindle 12 and returns to the original standing position by an extension due to an elastic restoring force of the pushing lever 13.
When the person seated is about to stand up from the seated state illustrated in
In this instance, the seat 6 and the backrest 11 moves to the unused position as illustrated in
As such, for example, even when the person seated sits on the seat 6, and stands up from a state in which the armrest 14 is put under a top plate of a desk, a gap between the armrest 14 and the top plate of the desk does not change, and the armrest 14 does not come into contact with the top plate and thus, the armrest 14 may be used safely.
A fitting convex portion may be provided at the attachment target portion 18 of the chair 5, and a fitting concave portion may be provided at the attachment portion 17 of the armrest 14. In addition, the armrest 14 may be attached to any component such as a seat, a backrest, and a backrest supporting lever of a chair, not being limited to the support base 5. In this case, when the armrest 14 is attached to a member whose width increases toward a front or a rear in planar view, it is preferable that the armrest 14 be attached to a portion where the width is increased.
Next, an example of an attachment structure of the elbow pad 16 in the chair with an armrest will be described with reference to
A top of the armrest fulcrum 15 is provided with a concave portion 25 in which an opening area has nearly the same size as that of the elbow pad 16, and a front end reaches half way of the flexure 15a, and the concave portion 25 forms an elbow pad attachment portion 26.
The elbow pad 16 has a thin plate shape which is slim in the front and back direction, and a front part thereof is provided with a flexure 16a that is curved obliquely downward. In addition, as illustrated in
As illustrated in
As illustrated in
As illustrated in
Next, as illustrated in
In this state, even when a force is applied to the front part of the elbow pad 16 in the upward and downward direction and in the front and back direction, the upward, forward, and backward directions of the concave portions 26d and 26e are blocked, and a shape opening inward is formed and thus, it is possible to effectively inhibit a position of the front part of the elbow pad 16 from being deviated in the upward and downward direction and the front and back direction.
In the attachment structure of the elbow pad, merely by engaging the engaging pieces 27a to 27c of the rear part and the convex portion 27f of the front part in the elbow pad 16 with the engaged pieces 26a to 26c and the concave portion 26f in the elbow pad attachment portion 26 of the armrest fulcrum 15, it is possible to easily attach the elbow pad 16 to the armrest fulcrum 15. In this case, the attachment structure may be embodied by reversing the front and rear directions of the armrest fulcrum 15 and the elbow pad 16. In addition, a lower surface of the elbow pad 16 may be provided with elements, similar to the concave portion 25, the engaged pieces 26a to 26c, the concave portions 26d to 26f, and the like in the armrest fulcrum 15, which are flipped from top to bottom, and the elbow pad attachment portion 26 of the armrest fulcrum 15 may be provided with elements, similar to the engaging pieces 27a to 27c, the elastic engaging pieces 27d and 27e, the convex portion 27f, and the like in the lower surface of the elbow pad 16, which are flipped from top to bottom.
That is, in the attachment structure of the elbow pad, a rear part or a front part of one of the elbow pad attachment portion 26 on a top of the armrest 14 and the elbow pad 16 is provided with the hook type engaged piece 26a opening forward or backward; the front part or the rear part is provided with the concave portion 26f opening in the upward and downward direction; the hook type engaging piece 27a opening backward or forward is provided at a position facing the engaged piece 26a of the other one of the elbow pad attachment portion 26 and the elbow pad 16; a position facing the concave portion 26f is provided with the convex portion 27f which protrudes in the upward and downward direction; the engaging piece 27a is engaged with the engaged piece 26a; and the convex portion 27f is fitted to the concave portion 26f, thereby attaching the elbow pad 16 to the top of the armrest 14.
In this way, merely by engaging the hook type engaging piece 27a provided at one of the elbow pad attachment portion 26 of the armrest 14 and the elbow pad 16 to the hook type engaged piece 26a provided at the other one, and by fitting the convex portion 27f provided at one of the elbow pad attachment portion 26 and the elbow pad 16 to the concave portion 26f provided at the other one from an upper side, it is possible to reliably attach the elbow pad 16 to an attachment target portion of the armrest 14 without greatly elastically deforming the elbow pad 16, and it is possible to enhance a flexibility of the design of the armrest 14 without a limitation on a material and a shape of the elbow pad 16 since the elbow pad 16 does not need to be formed from a soft and thick member.
Further, by providing the concave portion 26f and the convex portion 27f below the engaged piece 26a and the engaging piece 27a, it is possible to fit the convex portion 27f to the concave portion 26f after engaging the engaging piece 27a with the engaged piece 26a and thus, it is possible to further facilitate an attachment operation of the elbow pad 16. In this instance, by providing the flexure 15a that is curved downward at the front part in the elbow pad attachment portion 26 of the armrest 14, and providing the concave portion 26f or the convex portion 27f in the flexure 15a, it is possible to provide the concave portion 26f and the convex portion 27f below the engaged piece 26a and the engaging piece 27a with a simple configuration.
In addition, since the flexures 15a and 16a that are curved downward are provided at the elbow pad attachment portion 26 of the armrest fulcrum 15 and the elbow pad 16, respectively, the front part of the elbow pad 16 may not be greatly lifted when the elbow pad 16 is slid backward to engage the rear part of the elbow pad 16 with the elbow pad attachment portion 26 of the armrest fulcrum 15. That is, merely by sliding the elbow pad 16 backward while the elbow pad 16 is placed above the elbow pad attachment portion 26 so as to be deviated, and engaging the rear part of the elbow pad 16 with the elbow pad attachment portion 26, and then pressing the front part of the elbow pad 16 downward, it is possible to easily engage the front part of the elbow pad 16 with the elbow pad attachment portion 26. Accordingly, an attachment operation of the elbow pad 16 is facilitated.
Further, the elastic engaging pieces 27d and 27e of the elbow pad 16 are engaged with the concave portions 26d and 26e of the armrest fulcrum 15 by an elastic restoring force and thus, a width thereof in the upward and downward direction may be decreased. As such, the elbow pad 16 may be made thin as a whole. Further, it is possible to reliably attach the elbow pad 16 to the armrest 14.
Number | Date | Country | Kind |
---|---|---|---|
2010-234169 | Oct 2010 | JP | national |
2010-236202 | Oct 2010 | JP | national |
2010-236203 | Oct 2010 | JP | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/JP2011/073227 | 10/7/2011 | WO | 00 | 4/18/2013 |