U.S. patent application number 13/880266 was filed with the patent office on 2013-08-15 for chair with armrest.
This patent application is currently assigned to OKAMURA CORPORATION. The applicant listed for this patent is Ryou Igarashi, Hiroshi Masunaga, Youichirou Oda. Invention is credited to Ryou Igarashi, Hiroshi Masunaga, Youichirou Oda.
Application Number | 20130207427 13/880266 |
Document ID | / |
Family ID | 45975098 |
Filed Date | 2013-08-15 |
United States Patent
Application |
20130207427 |
Kind Code |
A1 |
Masunaga; Hiroshi ; et
al. |
August 15, 2013 |
CHAIR WITH ARMREST
Abstract
A chair with armrest 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, the 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 provided to the support base. When the
rear part of the seat rotates upward or downward, the height of the
armrest does not change, and therefore arms or the like are not
squeezed between the top plate of a desk and the armrest.
Inventors: |
Masunaga; Hiroshi;
(Kanagawa, JP) ; Oda; Youichirou; (Kanagawa,
JP) ; Igarashi; Ryou; (Kanagawa, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Masunaga; Hiroshi
Oda; Youichirou
Igarashi; Ryou |
Kanagawa
Kanagawa
Kanagawa |
|
JP
JP
JP |
|
|
Assignee: |
OKAMURA CORPORATION
YOKOHAMA-SHI, KANAGAWA
JP
|
Family ID: |
45975098 |
Appl. No.: |
13/880266 |
Filed: |
October 7, 2011 |
PCT Filed: |
October 7, 2011 |
PCT NO: |
PCT/JP2011/073227 |
371 Date: |
April 18, 2013 |
Current U.S.
Class: |
297/313 |
Current CPC
Class: |
A61G 5/14 20130101; A47C
3/00 20130101; A47C 7/546 20130101; A47C 7/54 20130101 |
Class at
Publication: |
297/313 |
International
Class: |
A47C 3/00 20060101
A47C003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 19, 2010 |
JP |
2010-234169 |
Oct 21, 2010 |
JP |
2010-236202 |
Oct 21, 2010 |
JP |
2010-236203 |
Claims
1. A chair with an armrest, comprising: 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.
2. The chair with an armrest according to claim 1, wherein 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.
3. The chair with an armrest according to claim 2, wherein 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.
4. The chair with armrest according to claim 1, wherein 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.
5. The chair with an armrest according to claim 1, wherein 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
another one of the attachment target portion and the attachment
portion, 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.
6. The chair with an armrest according to claim 5, wherein 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.
7. The chair with armrest according to claim 5, wherein 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.
8. The chair with an armrest according to claim 5, wherein, 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.
Description
FIELD
[0001] 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.
BACKGROUND
[0002] 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).
[0003] On the other hand, there is a chair in which an armrest is
connected to a seat (for example, see Patent Literature 2).
CITATION LIST
Patent Literature
[0004] Patent Literature 1: Japanese Laid-open Patent Publication
No. 2010-104463
[0005] Patent Literature 2: Japanese Patent No. 3156115
SUMMARY
Technical Problem
[0006] 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.
[0007] 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.
Solution to Problem
[0008] According to the invention, the above problem is solved as
below.
[0009] (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.
[0010] 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.
[0011] 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.
[0012] 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.
[0013] (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.
[0014] 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.
[0015] 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.
[0016] 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.
[0017] (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.
[0018] 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.
[0019] (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.
[0020] 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.
[0021] (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.
[0022] 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.
[0023] (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.
[0024] 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.
Advantageous Effects of Invention
[0025] 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.
BRIEF DESCRIPTION OF DRAWINGS
[0026] FIG. 1 is a front view of a chair with an armrest in an
unused state according to an embodiment of the present
invention.
[0027] FIG. 2 is a side view of the chair with an armrest
illustrated in FIG. 1.
[0028] FIG. 3 is a side view of the chair with an armrest
illustrated in FIG. 1 in a usage state.
[0029] FIG. 4 is a side view when a backrest is tilted backward in
the usage state of the chair with an armrest illustrated in FIG.
1.
[0030] FIG. 5 is an enlarged plan view illustrating a coupled
structure of a support base and the armrest when seen from V-V line
of FIG. 2.
[0031] FIG. 6 is a VI-VI line enlarged cross-sectional view of FIG.
2.
[0032] FIG. 7 is an enlarged perspective view of an attachment
portion of the armrest and an attachment target portion of the
support base of FIG. 2 when seen from a slant rear.
[0033] FIG. 8 is an enlarged exploded perspective view of an elbow
pad attachment portion and an elbow pad of the armrest when seen
from a slant front.
[0034] FIG. 9 is an enlarged perspective view of the elbow pad
attachment portion when seen from a slant lower part at a rear.
[0035] FIG. 10 is an enlarged longitudinal cross-sectional side
view illustrating the armrest and the elbow pad being
disassembled.
[0036] FIG. 11 is an enlarged longitudinal cross-sectional side
view illustrating a state in which the elbow pad is placed a little
ahead of the elbow pad attachment portion.
[0037] FIG. 12 is an enlarged longitudinal cross-sectional side
view illustrating a state in which the elbow pad is attached to the
elbow pad attachment portion.
[0038] FIG. 13 is a XIII-XIII line enlarged cross-sectional view of
FIG. 12.
[0039] FIG. 14 is a XIV-XIV line enlarged cross-sectional view of
FIG. 12.
DESCRIPTION OF EMBODIMENTS
[0040] Hereinafter, an embodiment of the present invention will be
described with reference to the accompanying drawings.
[0041] As illustrated in FIGS. 1 and 2, a chair with an armrest
includes a leg body 3 that includes five leg rods 2 which are
provided in a radial form and are provided with casters 1 at tips.
An extendable post 4 provided with a gas spring (not illustrated)
is stood at a center of the leg body 3, and a rear part of a
support base 5 which faces forward is fixed to a top of the post
4.
[0042] The support base 5 forms a shallow dish of a triangular
shape in planar view that is spread forward (see FIG. 5), and is
inclined in a front upward in side view as illustrated in FIG. 2.
In addition, as illustrated in FIG. 1, the support base 5 has an
upward U-shape when viewed from the front, and opens forward and
thus, it is easy to insert a member, a tool, and the like from the
front as well as a side or a rear during an operation of attaching
a member to the support base 5.
[0043] As illustrated in FIG. 2, a seat 6 includes a seat board 7
made of synthetic resins, and a cushion material 8 attached to a
top face thereof, and is rotatable about an axle 9 to an unused
position which is inclined in a rear upward and a usage position
which is horizontal or inclined in a rear downward direction as
illustrated in FIG. 3 by pivotally fixing both sides of a front end
of the seat board 7 to both sides a front end of the support base
5, respectively, using the axle 9 extending in a left and right
direction. It is preferable that the rotation range be about 15
degrees.
[0044] The seat 6 is normally impelled upward toward the unused
position by an impelling unit 10.
[0045] As illustrated in FIG. 2, front parts of portions formed by
bending forward both sides of a lower part of a backrest 11 are
pivotally fixed to both sides of a rear part of the seat board 7,
respectively, using a spindle 12 extending in the left and right
direction. The backrest 11 is rotatable about the spindle 12 to a
standing position that is directed nearly upward as illustrated in
FIGS. 2 and 3, and to a backward tilting position illustrated in
FIG. 4. A specific structure of the backrest 11 and a pivotally
fixed portion thereof are not directly related to the present
invention and thus, detailed illustration and description thereof
will not be presented.
[0046] As illustrated in FIG. 2, the rear part of the support base
5 is connected to a portion lower than the spindle 12 of the
backrest 11 through a pushing lever 13 that extends in a front and
back direction and may elastically extend and contract.
[0047] During a downward rotation of the seat 6 from the unused
position to the usage position (see FIG. 3), a lower end portion of
the backrest 11 is pushed backward by the pushing lever 13, and the
backrest 11 maintains a standing state. In addition, when the
pushing lever 13 elastically contracts, the backrest 11 may be
tilted backward as illustrated in FIG. 4 by resisting an elastic
restoring force of the pushing lever 13.
[0048] As illustrated in FIGS. 2 and 5, an armrest 14 is connected
to a portion, which is at a rear of the axle 9, of both lateral
sides 5a in a front part of the spread support base 5. As
illustrated in FIG. 1, the armrest 14 includes an armrest fulcrum
15 that has an inward L shape in front view by passing from the
support base 5 to a lower part of the seat 6 and standing upward
from an exterior side of the seat 6, and a soft elbow pad (elbow
pad member) 16 fixed to a top of the armrest fulcrum 15.
[0049] As illustrated in FIG. 2, a portion of the armrest fulcrum
15 standing from a side of the seat 6 forms a closed loop of a
substantially triangular shape in which a width in the front and
back direction gradually increases upward in side view. A rear face
of an upper portion of the armrest fulcrum 15 inclines in a rear
upward on a substantially similar curved surface to that of a front
face of a lateral portion of the backrest 11 in side view. An upper
portion of the armrest 14 may have an arbitrary shape such as a
downward L shape in side view, not being limited to a closed loop
shape in side view.
[0050] 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 FIGS. 6 and 7. As illustrated in FIGS.
6 and 7, an attachment portion 17 used to attach the armrest 14 to
the support base 5 is provided at a tip of a lower part facing
inward of the armrest fulcrum 15 in the armrest 14, and an
attachment target portion 18 that attaches the attachment portion
17 of the armrest 14 is provided on the lateral side 5a of the
front part of the spread support base 5.
[0051] 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.
[0052] 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.
[0053] 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.
[0054] As illustrated in FIG. 6, a protrusion size of the
protrusion 22 is less than a maximum reentrant size of the concave
portions 18a and 18b. An apical surface of the protrusion 22 is
provided with a screw hole 23 that passes through the support base
5 to reach an internal surface thereof toward a basal portion of
the protrusion 22.
[0055] 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.
[0056] 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.
[0057] 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 FIG. 2,
the seat 6 is positioned at the unused position which is inclined
in a rear upward, and the backrest 11 is maintained at the standing
position that is directed nearly upward by an extension of the
pushing lever 13.
[0058] In addition, in the unused state of FIG. 2, a void where a
hand is not squeezed when a person who is seated moves the hand
backward is provided between the rear face of the upper portion of
the armrest fulcrum 15 in the armrest 14 and the front face of the
lateral portion of the backrest 11 in planar view. As illustrated
in FIG. 1, voids are provided between the armrest fulcrums 15 and
15 in the right and left armrests 14 and 14, and a lower surface
and side surface of the seat 6. Thus, the armrest 14 does not
inhibit the seat 6 from rotating.
[0059] In this state, when the person is seated, the seat 6 rotates
to the usage position illustrated in FIG. 3 by resisting an added
force of the impelling unit 10 due to a load of the person, and the
person may promptly take an appropriate posture of having a seat.
In this instance, the backrest 11 attached to the seat 6 moves
downward and backward by resisting an added force of the pushing
lever 13. The rear face of the armrest 14 is inclined in a rear
upward and thus, a gap between the rear face and the backrest 11
increases toward the lower part of the armrest 14 where a hand or
clothes of the person seated frequently comes close when the
backrest 11 moves downward and backward. Thus, it is possible to
reduce a risk that a hand or an object is squeezed in the gap.
[0060] When the person seated pushes his back backward by leaning
against the backrest 11 from a seated state illustrated in FIG. 3,
the backrest 10 is rotated about the spindle 12 to the backward
tilting position illustrated in FIG. 4 while elastically
contracting the pushing lever 13.
[0061] 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.
[0062] When the person seated is about to stand up from the seated
state illustrated in FIG. 3, the seat 6 is impelled to rotate
upward toward the unused position by the impelling unit 10, and may
assist the person seated in standing up.
[0063] In this instance, the seat 6 and the backrest 11 moves to
the unused position as illustrated in FIG. 2, but the armrest 14 is
connected to the support base 5 and thus, a height thereof does not
change.
[0064] 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.
[0065] 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.
[0066] Next, an example of an attachment structure of the elbow pad
16 in the chair with an armrest will be described with reference to
FIGS. 8 through 14. As illustrated in FIG. 8, flexures 15a and 15b
are provided between an upper side portion and a front side
portion, and between the upper side portion and a rear side portion
in an upper portion of the closed loop of the armrest fulcrum 15,
respectively.
[0067] 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.
[0068] 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 FIG. 10, the elbow pad 16 is formed as an integral
unit of a soft member 16b and a hard member 16c.
[0069] As illustrated in FIGS. 8 and 10, a rear end and left and
right internal surfaces of a rear part of the concave portion 25 in
the armrest fulcrum 15 are provided with hook type engaged pieces
26a to 26c (see FIG. 13), opening forward and inward, in which an
upper side and a rear side are blocked. Left and right internal
surfaces in a front part of the concave portion 25 are provided
with concave portions (engaging holes) 26d and 26e (see FIG. 14)
which are blocked forward and in the front and back direction and
are opened inward. Further, a front end portion of the concave
portion 25 is provided with a concave portion 26f that opens
upward. The concave portion 26f is provided at the flexure 15a in
the front part of the armrest fulcrum 15 and thus, is positioned
below the engaged pieces 26a to 26c.
[0070] As illustrated in FIGS. 9 and 10, a rear end and both sides
of a rear part of an outer periphery 27 of the elbow pad 16 are
provided with hook type engaging pieces 27a to 27c (see FIG. 13)
that protrudes backward. Similarly, both left and right sides of a
front part are provided with elastic engaging pieces 27d and 27e
(see FIG. 14) which protrudes toward external sides in a horizontal
direction and may be elastically deformed. Further, a front end
portion is provided with a convex portion 27f which protrudes
downward. The convex portion 27f is provided at the flexure 16a of
the elbow pad 16 and thus, is positioned below the engaging pieces
27a to 27c.
[0071] As illustrated in FIG. 11, when the elbow pad 16 is attached
to the armrest fulcrum 15, the elbow pad 16 is positioned slightly
in front of a position confronted with the elbow pad attachment
portion 26, and is placed on top of the armrest fulcrum 15. Then,
as illustrated in FIGS. 12 and 13, when the elbow pad 16 is slid
backward, the engaging pieces 27a to 27c of the elbow pad 16 are
engaged with the engaged pieces 26a to 26c of the armrest fulcrum
15 from the front side.
[0072] Next, as illustrated in FIGS. 12 and 14, when a front part
of the elbow pad 16 is pressed downward, the convex portion 27f of
the elbow pad 16 is fitted to the concave portion 26f of the
armrest fulcrum 15 from an upper portion. In addition, the elastic
engaging pieces 27d and 27e of the elbow pad 16 moves downward
while being elastically deformed inward, and are engaged with the
concave portions 26d and 26e of the armrest fulcrum 15 by an
elastic restoring force. In this way, the elbow pad 16 is reliably
attached to the armrest fulcrum 15 while blocking the concave
portion 25 of the armrest fulcrum 15.
[0073] 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.
[0074] 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.
[0075] 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.
[0076] 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.
[0077] 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.
[0078] 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.
[0079] 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.
REFERENCE SIGNS LIST
[0080] 1 Caster [0081] 2 Leg Rod [0082] 3 Leg Body [0083] 4 Post
[0084] 5 Support Base [0085] 5a Lateral Side [0086] 6 Seat [0087] 7
Seat Board [0088] 8 Cushion Material [0089] 9 Axle [0090] 10
Impelling Unit [0091] 11 Backrest [0092] 12 Spindle [0093] 13
Pushing Lever [0094] 14 Armrest [0095] 15 Armrest Fulcrum [0096]
15a, 15b Flexure [0097] 16 Elbow Pad [0098] 16a Flexure [0099] 16b
Soft Member [0100] 16c Hard Member [0101] 17 Fitting Portion [0102]
17a, 17b Fitting Convex Portion [0103] 17c Reentrant Portion [0104]
18 Fitting Target Portion [0105] 18a, 18b Fitting Concave Portion
[0106] 19 Concave Portion [0107] 20 Screw Through Hole [0108] 21
Screw [0109] 22 Protrusion [0110] 23 Screw Hole [0111] 24 Guard
Portion [0112] 25 Concave Portion [0113] 26 Elbow Pad Attachment
Portion [0114] 26a to 26c Engaged Piece [0115] 26d to 26f Concave
Portion [0116] 27 Attachment Portion [0117] 27a to 27c Engaging
Piece [0118] 27d, 27e Elastic Engaging Piece [0119] 27f Convex
Portion
* * * * *