JP7686532B2 - Armrest and chair equipped with same - Google Patents

Description

The present invention relates to an armrest that can be attached to a chair and a chair equipped with the same, and more specifically to an armrest that has a good appearance and a chair equipped with the same.

Chairs equipped with armrests that have arm bodies formed with frame-shaped parts are known. As a variation of such armrests, a configuration in which a panel is attached to an opening in the frame-shaped part is also known. The applicant has proposed Patent Document 1 (JP Patent Publication No. 2001-321242) as an example of a configuration for attaching a panel to an opening in such a frame-shaped part.

JP 2001-321242 A

The armrest disclosed in Patent Document 1 is configured so that a core material is attached across the opening of the frame, the core material is sandwiched between two panels, and the panels are fixed to the core material using screws on the outer surface of each panel. This configuration makes it possible to attach and detach the panels reliably and easily, but there is an issue that the screws for fixing the panels to the core material are exposed, which makes for a less than ideal appearance.

The present invention aims to provide an armrest with an excellent appearance and a chair equipped with the armrest, by not exposing the screws for fastening the armrest body and the panel when attaching the panel to the armrest body having a frame-shaped portion.

In other words, the present invention is an armrest comprising an armrest body attached to the main body of a chair and having a frame-shaped portion, and a panel attached to an opening in the frame-shaped portion, at least one first engagement portion being arranged on the inner surface of the opening and a second engagement portion paired with the first engagement portion being arranged on the outer surface of the panel, the first engagement portion being a recess which is a machined hole, and the second engagement portion being a protrusion formed by the thick portion and head portion of a shoulder screw raised on the inner surface of the opening, or the first engagement portion being a protrusion formed by the thick portion and head portion of a shoulder screw raised on the inner surface of the opening, and the second engagement portion being a recess which is a machined hole .

This eliminates the need for screws to fasten the elbow body and the panel, and eliminates exposure of screws on the panel surface, providing an armrest with an excellent appearance. This also simplifies the configuration of the first and second locking parts, reducing manufacturing costs and improving the dimensional accuracy of the engagement parts, thereby improving the accuracy of attachment of the panel to the elbow body.

In addition, it is preferable that a screw is screwed from the outer peripheral surface of the frame-shaped portion to the frame-shaped portion at a position opposite to the arrangement positions of the first engagement portion and the second engagement portion, and further, it is more preferable that the first engagement portion is arranged on either the lower, front or rear side of the inner peripheral surface of the opening, and the second engagement portion is arranged on either the lower, front or rear side of the outer peripheral surface of the panel, and that the screw is covered by a cover attached to the outer peripheral surface of the frame-shaped portion.

This allows the panel to be more firmly fixed to the elbow body. Furthermore, if screws are used to fix the elbow body and the panel, the cover attached to the elbow body can prevent the screws from being exposed, achieving both improved fixing strength between the elbow body and the panel and a good appearance.

It is also preferable that the opening be formed in a frustum shape that gradually narrows from the seat side toward the outside.

It is also preferable that the outer diameter of the inner surface material, which is the surface facing the seat, of the panel is different from the outer diameter of the outer surface material, which is the outer surface.

As a result, the panel attached to the elbow body can be prevented from falling off the elbow body during normal use without the need for fixing screws.

Furthermore, the chair of the present invention is characterized by having an armrest as described above.

The configuration of the armrest and chair equipped with the same in the present invention makes it possible to provide an armrest and chair equipped with the same that have excellent appearance, without exposing the screws for fastening the armrest body and the panel when attaching the panel to the armrest body having a frame-shaped portion.

FIG. 1 is a front perspective view showing a chair to which an armrest is attached according to an embodiment of the present invention. FIG. 2 is a rear perspective view showing a chair to which an armrest is attached according to the present embodiment. FIG. 2 is a perspective view showing the chair shown in FIG. 1 with the leg support, the right armrest and the backrest removed. FIG. 4 is an exploded view of the left armrest of FIG. 3 removed. FIG. FIG. FIG. FIG. FIG. FIG. 2 is a perspective view from the lower rear of the spine shell. FIG. 2 is a perspective view showing an armrest body of the armrest in this embodiment. FIG. 2 is a perspective view showing a panel in the present embodiment. 13 is a perspective view showing the state in which the inner surface material and shoulder screws have been removed from the panel shown in FIG. 12. FIG. 13 is a perspective view showing the state in which the panel shown in FIG. 12 is attached to the opening of the elbow body shown in FIG. 11 . 13 is a perspective view showing the installation status of the screws that secure the elbow body and the panel. FIG. 11 is a cross-sectional view showing the internal structure of the armrest with the fixing screws attached. FIG. FIG. 2 is a perspective view of an armrest according to the present embodiment.

The configuration of the present invention will be described in detail below based on the embodiment shown in the drawings. In this specification, the front, back, left and right directions are defined with respect to the seated person. That is, "front or forward" means the front or forward of the chair 100 and the seated person in the seat 30 and the backrest 50, respectively, and "rear or rear" means the rear or rear of the chair 100 and the seated person in the same manner. In addition, the direction perpendicular to the front-back direction in the horizontal plane is the left-right direction in the seat 30 and the backrest 50, respectively, for the seated person, and is also the width direction of the chair 100. Furthermore, "upper" and "lower" mean the upper and lower of the chair 100 and the seated person in the seat 30 and the backrest 50, respectively, and are upper and lower in the vertical plane.

Figures 1 and 2 show one embodiment of a chair 100 equipped with an armrest 60 of the present invention. In this embodiment, the chair 100 comprises a leg support 10, a main frame 20 attached to the leg support 10, a seat 30 and a backrest support member 40 swingably connected to the main frame 20, and a backrest 50 and armrest 60 attached to the backrest support member 40. A headrest 55 is attached to the backrest 50. The armrest 60 is detachably attached to the rear bridge frame 41 by screws.

(Leg support 10)
As shown in Figures 1 and 2, the leg support 10 in this embodiment has five leg blades 12, each of which has a caster 11 attached to its tip and each of which has a base end attached to the lower end of the leg support 10 in a radial manner in a plan view. The leg support 10 in this embodiment also has a built-in lifting mechanism (not shown) for extending and contracting the leg support 10 in the height direction. The lifting mechanism is raised and lowered by operating a lifting lever 37 disposed at the right end of the front bridge frame 33. The main frame 20 is attached to the upper end of the leg support 10 thus formed, as shown in Figures 1, 3 and 4.

(Main frame 20)
The main frame 20 has a bracket 21 disposed at the rear part to which a backrest support member 40 for mounting a backrest 50 is swingably connected, and a front link 23 disposed at the front part to which a seat support member 31 for mounting a seat part 30 is swingably connected. The main frame 20 is box-shaped to increase the mechanical rigidity (especially torsional rigidity, etc.) of the structure and to accommodate a reaction mechanism (not shown) inside. This reaction mechanism generates a force that pushes back the backrest 50 in conjunction with the backward tilt of the backrest 50 between the backrest support member 40 swingably supported at the rear end side of the main frame 20 and a link shaft (in this embodiment, also serving as an operating shaft for reaction adjustment: not shown) at the front end side of the main frame 20.

The main frame 20 is supported by the leg support 10 by fitting the gas spring of the leg support 10 to the tubular portion 29 on the rear lower surface. A shaft hole 25 is formed in the bracket 21 erected on the rear upper surface, and the bearing portion 44 of the rear bridge frame 41 is connected to this shaft hole 25 via the backrest rotation axis SJ (see FIG. 1), and supports the seat portion 30 and the backrest support member 40 (backrest 50) so that they can swing freely. A pair of left and right front links 23 are arranged in front of the main frame 20. The bearing portion 33A of the front bridge frame 33 that supports the seat frame 32 is connected to the front link 23 so that it can swing freely. The main frame 20 in this embodiment is integrally formed by aluminum die casting or the like, but is not limited to this, and may be formed into a box shape or other shape having a bearing portion by welding steel material or the like. In addition, a switching lever 27 for switching between swinging and fixing the front link 23 is disposed on the right side surface of the main frame 20. A reaction mechanism including a compression coil spring is provided inside the main frame 20. This reaction mechanism can adopt a known configuration disclosed in JP 2021-61967 A, so a detailed description will be omitted here.

In this embodiment, as shown in FIG. 3, the front link 23 is formed with almost the same surface as the surfaces (side, bottom, and top) that constitute the main frame 20, and is designed to look as if it constitutes a part of the main frame 20 when viewed from the side. For example, it has a ceiling part (not shown) and a bottom part (not shown) that close the space between the left and right front links 23 without interfering with the bearing part 33A, etc., and provides design continuity with the main frame 20. The main frame 20 and the front link 23 are elements that appear as a single mass that is generally thinner and smarter toward the tip, but there are parts that are divided into the front link 23 and the main frame 20 by a groove cut in a semicircular arc. Specifically, for example, the tip side is formed into an oval shape that is smaller in diameter than the base end side and generally narrows toward the tip. The top surface of the main frame 20 is formed by the main frame top cover (not shown).

The positional relationship between the main frame 20 and the front link 23 is such that they are arranged on one axis in the initial position (when no one is seated). In other words, the main frame 20 is arranged to extend on an extension of the line connecting the front end of the front link 23 and the backrest rotation axis SJ. This allows for a design that looks as if it were a single component and gives a neat and tidy impression. In this way, the mechanical parts under the seat can be made smaller and thinner, improving space efficiency and creating a smart and attractive exterior.

(Seat portion 30)
The seat portion 30 is not limited to a specific structure or shape, but in this embodiment, as shown in Figures 3 to 5, it is a so-called all-around seat structure in which the inner shell 35 is completely covered with cushioning material 36 and a bag-shaped upholstery (not shown), and is mounted to the main frame 20 via a seat support member 31 in a rockable manner.

The seat support member 31 of this embodiment has a ring-shaped seat frame (rectangular frame with an open inner side) 32, a front bridge frame 33 that supports the front of the seat frame 32, and a bracket 34 for connecting a position slightly rearward of the middle of the seat frame 32 to the backrest support member 40. A bearing portion 33A in the center of the front bridge frame 33 is connected to and supported by the front link 23 of the main frame 20 so as to be able to swing freely, while a bracket 34 on the rear side of the seat frame 32 is connected to and supported by a rotating shaft (not shown) by the bracket 47 of the backrest support member 40 so as to be able to swing freely. Therefore, the seat portion 30 moves in conjunction with the movement of the backrest 50.

The front bridge frame 33 is a curved wing-like frame that extends upward to the left and right with a convex central portion facing downward, and in combination with the rear bridge frame 41 and back shell mounting portion 42 of the backrest support member 40, creates space under the seat (see Figures 3 and 4). This allows the mesh and cushion that make up the seat structure to flex vertically without being damped. It also has the effect of making the design look lighter.

The mounting position of the rear bracket 34 of the seat frame 32 relative to the rear bridge frame 41 is located forward of the backrest rotation axis (i.e., the shaft hole 25) of the rear bridge frame 41, and is located at a position where the seat frame 32 (i.e., the seat portion 30) can be lifted when the backrest support member 40 tilts backward. In other words, the seat portion 30 is lifted as the backrest 50 tilts backward, and a part of the body weight of the seated person acts as resistance against the backward tilting of the backrest 50 (the rocking resistance is weight sensitive), forming a body weight sensing reaction force imparting mechanism (also called a body weight sensitive reaction force imparting mechanism).

On the other hand, in this embodiment, the seat structure is composed of an annular inner shell (core) 35 with a mesh (not shown) as a structural member that evenly distributes and supports the weight of the seated person, a cushion material 36 such as urethane foam placed on the mesh of the inner shell 35, and an upholstery (not shown) that wraps the cushion material 36 and the inner shell 35, and is placed on the seat frame 32 (corresponding to the outer shell) and fixed by screwing from below through the screw holes 39. The upholstery in this embodiment has a string hole for passing a string through, for example, on the periphery, and is a type that wraps the cushion material 36 and the inner shell 35 by pulling the string to tighten the upholstery, and the end of the string needs to be processed. Therefore, a ring-shaped string groove 35A (see FIG. 5) for storing the wrapping string is provided in the center of the upper surface of the seat frame 32, and the string (not shown) is stored in the string groove 35A of the seat frame 32 so that it does not appear from the outside. Of course, not only the strings but also the edges of the upholstery themselves can be placed in the string groove 35A so that they are not visible from the outside. Note that the seat structure of this embodiment has a double elastic support structure of mesh and urethane to improve seating comfort, but this is not limited to this, and elasticity can be provided by urethane alone or mesh alone.

In this embodiment, the front bridge frame 33 and the seat frame 32, as well as the rear bridge frame 41 and the back shell mounting portion 42, are integrally molded, but in some cases they may be molded separately and then connected.

(Lifting lever 37)
The wall part rising toward the seat frame 32 at the right end of the front bridge frame 33 is provided with a space 38 into which a lift lever 37 for opening and closing the valve of the gas cylinder of the leg support 10 is fitted. This allows the frame shape of the seat support member 31 to be streamlined and the mounting position of the lift lever 37 to be smartly arranged. In addition, the operating wire W can be laid out along the front bridge frame 33. Moreover, instead of creating a lever receiver (box-shaped) in the frame itself, the independent lift lever 37 is accommodated in the space 38 of the front bridge frame 33, so that the parts cost and assembly cost can be reduced. The ball part WT at the tip of the operating wire W is anchored to a ball receiver at the upper end of one side of an L-shaped link (a so-called bell crank; not shown) supported so as to be freely swingable by a link holder (not shown), and is arranged so that the valve of the gas cylinder is pushed down on the other side by pulling the operating wire W.

(Backrest support member 40)
As shown in Figures 3 and 6, the backrest support member 40 has a rear bridge frame 41 and an annular back shell attachment part 42 (a rectangular frame with an opening on the inside). The rear bridge frame 41 is a curved wing-like frame that extends upward to the left and right with a central part that is convex downward, and in combination with the rear annular back shell attachment part 42, creates a space under the seat at the rear of the seat part 30. This allows the mesh and cushion that make up the seat structure (not shown) to bend vertically without being cushioned. It also has the effect of making the design look lighter.

Furthermore, as shown in Figs. 3 and 6, the rear bridge frame 41 is provided at its lowermost center with a bearing portion 44 for inserting the backrest rotation axis SJ of the bracket 21 at the rear end of the main frame 20 to connect it so as to be freely swingable, and an arm portion 45 that hangs down diagonally downward and forward to support one spring mount (not shown) of the spring-type backrest reaction mechanism, which is provided to form a spring-type backrest reaction mechanism that pushes one spring mount of the spring-type backrest reaction mechanism forward when the backrest 50 tilts backward. In addition, the rear bridge frame 41 is provided at both ends of its upper surface with brackets 47, which are mounting portions for mounting the rear bracket 34 of the seat frame 32 so as to be freely swingable.

Here, as shown in Figs. 3 and 6, the bracket 47 is located forward of the bearing portion (i.e., the shaft hole 25 which is the backrest rotation axis) 44, that is, at a position where the seat portion 30 is lifted when the rear bridge frame 41 is tilted backward. For example, the backrest support member 40 is inclined so that the rear bridge frame 41 protrudes obliquely upward and forward when the bearing portion (i.e., the shaft hole 25 which is the backrest rotation axis) 44 of the rear bridge frame 41 is at a position where the seat portion 30 is lifted when the backrest 50 is tilted backward, and the back shell mounting portion 42 at the rear of the rear bridge frame 41 protrudes obliquely upward and backward when the bearing portion (i.e., the shaft hole 25 which is the backrest rotation axis) 44 of the rear bridge frame 41 is at the center. In addition, the flange 43 for inserting the back shell 51 from the rear is formed on the outer circumferential surface of the back shell mounting portion 42 so as to surround the back shell mounting portion 42 and to protrude toward the rear and both the left and right sides.

In addition, as shown in Figures 3 and 6, armrest mounting seats 48 for mounting armrests 60 are provided at both ends of the rear bridge frame 41. When the armrest 60 is not present, the armrest mounting seats 48 are exposed as recesses, and are therefore covered with a cover that conceals the recesses, i.e., a cover that is formed of a surface that is flush with the outer shell surface of the rear bridge frame 41. Thus, the backrest support member 40 has a rational structure that integrates the rear bridge frame 41, bearing portion 44, arm portion 45, back shell mounting portion 42, seat frame mounting portion (bracket 47), and armrest mounting seat 48 into one.

(Backrest 50)
The backrest 50 is not limited to a specific structure and shape. As shown in FIG. 6, the backrest 50 of this embodiment is composed of a back shell 51 and a back covering material (not shown), and a so-called all-around structure is adopted in which the back shell 51 is completely covered with a cushion material 54 and a bag-shaped upholstery (not shown). The headrest 55 has a main body portion 55A and a fixing portion 55B, and is fixed to the back side of the back plate 52 constituting the back shell 51 by a screw at the fixing portion 55B. The back side of the headrest 55 is formed in a lattice shape, achieving both mechanical strength and weight reduction. The backrest 50 formed in this way is mounted on the main frame 20 via the backrest support member 40 so as to be able to swing.

The backrest 50 of this embodiment is configured so that a flexible back plate 52 is placed in the center of a back shell 51, and both sides are supported by rigid back frames 53, and the back is completely covered. Specifically, as shown in FIG. 6, the back shell 51 of this embodiment is composed of a pair of rigid back frames 53 on the left and right and a flexible back plate 52, and has a component configuration that is rational in terms of strength.

As shown in FIG. 6, the backrest 50 in this embodiment is formed in a shape that is convex toward the front in side view (i.e., a dogleg shape), and is curved so that it is convex toward the rear in plan view. The back mounting seat 56 at the lower end of the back shell 51 is fitted into the flange 43 of the back shell mounting part 42 of the backrest support member 40 and screwed to form a continuous L-shape in side view. The screwing is performed by screwing a screw (not shown) from the inside of the annular back shell mounting part 42, so that the U-shaped back mounting seat 56 that protrudes forward of the back shell 51 and the back shell mounting part 42 are connected and integrated without being visible from the outside. As a result, in this embodiment, the backrest support member 40 and the back shell 51 of the backrest 50 are configured with a neat L-shaped appearance in side view.

As shown in FIG. 7, the back mounting base 56 of the back shell 51 (i.e., the portion that fits into the back shell mounting portion 42 of the backrest support member 40) is bent forward to form an L-shape in side view, and the back frame 53 portions on both sides project further forward than the central back plate 52 to form a U-shape in plan view that surrounds the back shell mounting portion 42, and is inserted into the back shell mounting portion 42 from three directions, the left and right sides and the back, to firmly connect to the back shell mounting portion 42.

The back frame 53 is preferably made of glass fiber reinforced nylon such as PA6-GF (polyamide 6) to ensure the mechanical rigidity of the structure. On the other hand, the back panel 52 is preferably made of an olefin resin such as PP (polypropylene) to have a certain degree of flexibility to improve the comfort of the backrest 50. In other words, the strength of the backrest 50 is ensured by the back frames 53 on both sides, while the softness of the backrest 50 is ensured by the central back panel 52.

The back frame 53 in this embodiment has a vertically elongated shape, as shown in, for example, Figures 6 to 9, and is preferably applied to the lower left and right sides of the back panel 52, for example, most of the back panel 52, for example, up to the area above the back support point (the part pressed against the waist of a seated person). This allows the back panel 52 to function as a reinforcing member. On the other hand, the back panel 52 is formed into a desired shape, for example, a roughly rectangular shape when viewed from the front, including the part to which the back frame 53 is applied, with reinforcing edges.

The back panel 52 and the back frames 53 on both sides are connected and integrated by fitting the concaves and convexes parallel to the front surface of the backrest 50 and fastening the fitting parts with screws. In this state, it is attached to the annular back shell mounting part 42 at the rear of the backrest support member 40. The reference symbol 52C in the figure is a screw hole.

In order to make the connection between the back frame 53 and the back plate 52 strong and smooth and continuous with few irregularities, steps 52A are provided on both side edges of the back plate 52, as shown in Figs. 6 to 9. While this step 52A forms a part that partially overlaps with the back frame 53 (i.e., flange 52B), a fitting portion 53B with a U-shaped cross section is formed on the inner side of the back frame 53 facing the back plate 52, which forms a groove 53A into which the flange 52B of the back plate 52 fits. In this way, the back plate 52 and the back frame 53 are integrated by fitting the flange 52B into the groove 53A. The rigidity of the back frame 53 is further increased by making the fitting portion 53B that overlaps with the back plate 52 a U-shaped cross-sectional structure that can be bent into an L shape. Moreover, the rigidity is further increased by fitting the flange 52B of the back plate 52 into the groove 53A. In addition, the backrest 50 of this embodiment has a rear support portion 53C that wraps around the rear side of the backboard 52 and protrudes inward (i.e., by changing the length) from one edge of the U-shaped fitting portion 53B that forms the groove 53A into which the flange 52B of the backboard 52 fits. This creates a portion that overlaps with the backboard 52 in the front-to-rear direction, further increasing strength. Note that the backrest 50 of this embodiment has a so-called all-encompassing structure that completely covers the back shell 51, so the fitting portion between the flange 52B of the backboard 52 and the groove 53A of the back frame 53 is concealed.

On the other hand, a flange groove 56A is formed in the back mounting seat 56 of the back shell 51 so as to face the back shell mounting part 42 of the backrest support member 40. For example, as shown in Figures 6 to 10, the flange groove 56A is formed in the center for fitting the flange 43 of the back shell mounting part 42, and above and below it are provided a front upholstery groove 56B and a back upholstery groove 56C for sandwiching the upholstery together with a fastening member, such as a PP (polypropylene resin) cord, sewn to the end (i.e., edge) of the upholstery.

The back shell 51 of this embodiment is divided into three parts: the left and right back frames 53 and the central back panel 52, and each part is punched in one direction, so the mold structure does not require a slide mold or the like, and the mold structure can be simplified and made less costly.

In addition, the position where the full covering that covers the back shell 51 can be fixed while applying tension, for example, in the present embodiment where the full covering is placed from above, is provided so that the end and edge of the upholstery can be fixed to the side opposite the top side, i.e., the inner surface of the U-shaped back attachment base 56 on the lower side (see Figure 7). For example, on the outer surface of the bottom side of the back shell 51 (the bottom side of the back panel 52), two upholstery grooves are formed one above the other to fit the edges of the upholstery equipped with thin plate-like locking members, i.e., the front upholstery groove 56B into which the edge of the front upholstery of the opening of the full covering is inserted, and the rear upholstery groove 56C into which the edge of the rear upholstery is inserted. This upholstery fixing structure is such that even if a pulling force is applied to the upholstery, the locking members are caught in the upholstery grooves and do not come out of the upholstery grooves.

Between the front upholstery groove 56B and the back upholstery groove 56C, a flange groove 56A is formed into which the flange 43 of the back shell mounting part 42 is inserted. A vertical rib 56D is formed in the middle of this flange groove 56A, crossing the flange groove 56A (i.e., the flange groove 56A is formed intermittently), and the vertical rib 56D is provided with a female thread 56E for screwing the back shell mounting part 42. On the other hand, the flange 43 of the back shell mounting part 42 is formed intermittently in the circumferential direction so that the flange 43 can be inserted into the flange groove 56A without interfering with the vertical rib 56D provided in the flange groove 56A. Therefore, the edge of the back wrap is hidden to neaten the upholstery storage, and the upholstery is firmly clamped to ensure the strength of the fixation.

In this embodiment, the grooves 56B for the front upholstery and the grooves 56C for the back upholstery are provided on the inner peripheral surface of the U-shaped back mounting base 56 of the back shell 51, but they are not limited to this and can be provided in any position as long as they can be fixed while applying tension to the entire cover. For example, they may be provided on the top edge or side of the back shell 51. Also, instead of using the back shell 51, they may be fixed by covering it with a back frame (hollow frame body) not shown.

(Reaction mechanism: Body weight sensing)
The chair 100 of this embodiment uses, as a reaction mechanism, a spring-based reaction mechanism that obtains a reaction force by compressing the spring when the backrest 50 tilts backward, and a weight-sensitive (or sensing) reaction force applying mechanism that makes the resistance against the rocking of the backrest 50 proportional to (sensitive to) the weight of the user by linking the mechanism so that the seat frame 32 is lifted when the backrest 50 is tilted backward. Since a known configuration can be adopted for such a reaction force applying mechanism, a detailed description thereof will be omitted here.

(Armrest 60)
An armrest 60 is attached to the armrest mounting seat 48 of the backrest support member 40 as the main body of the chair 100. The armrest 60 in this embodiment is formed by attaching a panel 66 to a frame-shaped portion 62 provided on an armrest main body 61. The structure of the armrest 60 in this embodiment will be described below with reference to Figs. 11 to 17. The armrests 60 are attached to the left and right positions of the seat 30, respectively, but since they are symmetrical to each other, only one of the armrests 60 will be described here. As shown in Fig. 11, the armrest main body 61 has a frame-shaped portion 62 and a connecting arm 63 formed integrally with the frame-shaped portion 62. In this embodiment, the opening 62A of the frame-shaped portion 62 has a so-called inverted trapezoid shape, but the shape of the opening 62A is not particularly limited. The opening 62A in this embodiment is formed in a frustum shape in which the outer opening surface 62Y is smaller than the inner opening surface 62X. In addition, recessed holes 65 as recesses that are first engaging portions are formed at two locations at a required distance from each other on the lower inner peripheral surface of the opening 62A. Such recessed holes 65 may be machined holes machined by a machine tool such as a milling machine, but are not limited to machined holes.

Next, the panel 66 to be attached to the opening 62A of the frame-shaped portion 62 will be described. FIG. 12 is a perspective view of the panel 66 in this embodiment. FIG. 13 is a perspective view showing the state in which the inner surface material 67 and the stepped screw 69 as the convex portion, which is the second locking portion, have been removed from the panel 66 shown in FIG. 12. In this embodiment, the panel 66 has four core materials 64A to 64D arranged along the contour line of the opening 62A, and the core materials 64A to 64D are sandwiched in the thickness direction between the inner surface material 67 and the outer surface material 68. The core materials 64A to 64D and the inner surface material 67 and the outer surface material 68 are integrated by a known method such as an adhesive. The inner surface material 67 and the outer surface material 68 are both formed in a laminate of a substrate and a decorative plate. On the outer peripheral surface of the panel 66 formed in this way, stepped screws 69 as the convex portion, which is the second locking portion, are erected at two locations corresponding to the positions of the recessed holes 65. Here, the shoulder screw 69 is erected on the lower core material 64A so that the entire large diameter portion of the shoulder screw 69 and the screw head are exposed from the outer periphery of the panel 66.

The thickness dimension of the panel 66 thus formed is the same as the thickness dimension of the frame-shaped portion 62. In addition, since the opening 62A of the frame-shaped portion 62 is formed in a frustum shape with the outer opening surface 62Y being smaller than the inner opening surface 62X, the outer diameter dimension of the inner surface material 67 and the outer diameter dimension of the outer surface material 68 are made different, and the panel 66 is also formed in a frustum shape. In this way, the panel 66 to be attached to the opening 62A of the frame-shaped portion 62 is also formed in a shape that matches the shape of the opening 62A, so that the accuracy of attachment of the panel 66 to the frame-shaped portion 62 can be improved.

Next, the panel 66 is inclined from the side of the inner opening surface 62X as shown in FIG. 14, and the head and large diameter portions of the stepped screws 69 are inserted into the recessed holes 65 formed in the opening 62A as shown by the arrow A. After this, the panel 66 is erected so that the inner surface of the panel 66 is flush with the inner opening surface 62X as shown by the arrow B, and the panel 66 is fitted into the opening 62A. By using the stepped screws 69 as the protruding portions, which are the second locking portions, as in the panel 66 of this embodiment, the protruding heights of the stepped screws 69 from the lower outer peripheral surface of the panel 66 can be easily made uniform, and the installation accuracy of the panel 66 into the opening 62A of the frame-shaped portion 62 can be improved. In this embodiment, the stepped screws 69 are used as the protruding portions, which are the second locking portions, but it is of course possible to use normal screws. In this case, it is preferable to mark the required height position on the outer peripheral surface of the screw in order to make the screw-in depth into the core material 64A uniform.

After the panel 66 is attached to the armrest body 61, it is preferable to fix the frame 62 and the panel 66 to the upper core material 64B from the outer peripheral surface side of the frame 62 using a fixing screw 80 as shown in Figure 15. Figure 16 shows the internal structure of the armrest 60 with the fixing screw 80 attached. As shown in Figure 16, the panel 66 attached to the opening 62A of the frame 62 is in a state in which the thick part and the screw head part of the stepped screw 69 erected on the lower outer peripheral surface of the panel 66 enter the recessed hole 65 formed on the lower inner peripheral surface of the frame 62. In addition, the fixing screw 80 is fixed to the side opposite to the side where the recessed hole 65 and the stepped screw 69 are arranged, and the frame 62 and the panel 66 are firmly fixed. In addition, it is preferable that the positions of the recessed hole 65 as the first engaging portion, which is the recess, and the shoulder screw 69 as the second engaging portion, which is the protruding portion, and the position where the fixing screw 80 is screwed in face each other, but this is not a limitation.

In this embodiment, the fixing screws 80 are exposed on the outer surface of the frame-shaped portion 62, but because the armrest 90 is attached to the top surface of the frame-shaped portion 62, the appearance is not marred by the presence of the fixing screws 80 attached to the top surface of the frame-shaped portion 62. In this manner, the armrest 60 as shown in FIG. 17 can be assembled. The armrest 60 thus formed can be fixed by inserting the connecting arm 63 of the armrest body 61 into an insertion hole (not shown) formed in the rear bridge frame 41 of the backrest support member 40 and fastening it to the bottom surface of the rear bridge frame 41 with a screw.

The chair 100 equipped with the armrest 60 according to the present invention has been described in detail above, but the armrest 60 of the present invention is not limited to the above embodiment. For example, the above embodiment illustrates an example in which the armrest 60 is attached to the armrest mounting seat 48 of the backrest support member 40 of the chair 100, but the armrest 60 may be attached to the main body of the chair 100. Examples of the main body of the chair 100 include the seat support (seat frame 32) and the backrest support member 40.

The armrest 60 of the present invention is also suitable for retrofitting a panel 66 to a normal armrest body 61 (not having a first locking part) that is already attached to the body of the chair 100. In this case, the armrest body 61 is removed from the chair 100, and the panel 66 used in this embodiment can be retrofitted by cutting a recessed hole 65 as a first locking part into the inner peripheral surface of the frame part 62 of the armrest body 61 using a milling machine or the like. Since the armrest body 61 is equipped with an armrest 90 as a cover, even if the fixing screw 80 that fixes the armrest body 61 and the panel 66 is attached from the outer peripheral surface of the armrest body 61, the fixing screw 80 can be hidden by attaching the armrest 90 on top of the fixing screw 80, and the appearance of the armrest 60 can be improved.

In addition, in this embodiment, the first locking portion is disposed on the lower inner peripheral surface of the frame-shaped portion 62, but the location of the first locking portion on the inner peripheral surface of the frame-shaped portion 62 is not limited to the lower inner peripheral surface, and may be any of the upper inner peripheral surface, the front inner peripheral surface, and the rear inner peripheral surface. In particular, when the first locking portion is disposed on the upper inner peripheral surface of the frame-shaped portion 62, the fixing screw 80 that fixes the frame-shaped portion 62 and the panel 66 is attached from the lower outer peripheral surface of the frame-shaped portion 62. Therefore, it is particularly preferable in that the appearance of the armrest 60 can be kept good under normal use conditions without having to attach a cover to hide the fixing screw 80. In addition, the armrest 60 in this embodiment is exemplified as a form in which the recessed hole 65 as the first locking portion is disposed on the frame-shaped portion 62 of the arm main body 61, and the stepped screw 69 as the protruding portion as the second locking portion is disposed on the outer peripheral surface of the panel 66, but is not limited to this form. As a variation of this configuration, a recessed portion serving as the first locking portion can be provided on the outer peripheral surface of the panel 66, and a protruding portion serving as the second locking portion can be provided on the inner peripheral surface of the frame portion 62 of the elbow body 61.

In addition, in the present embodiment, the armrest 60 is illustrated as using four core materials 64A-64D, but a frame-shaped core material (not shown) formed in a frame shape can also be used. In addition, in the present embodiment, the armrest 60 is illustrated as using a shoulder screw 69 as the protruding portion that is the second engagement portion, but this is not limited to this form. In addition, the protruding portion that is the second engagement portion can also be formed integrally with the frame-shaped core material on the outer circumferential surface of the frame-shaped core material.

Furthermore, with respect to the configuration of the present embodiment described above, it is also possible to adopt a form in which the optional components described in the specification are omitted. It is also possible to adopt a form in which the modified examples described in the specification and other known configurations are appropriately combined.

10: Leg support 11: Caster, 12: Leg wing 20: Main frame 21: Bracket, 22: Front bridge frame, 23: Front link, 25: Axle hole,
27: Switching lever, 29: Cylinder portion, 30: Seat portion, 31: Seat support member, 32: Seat frame, 33: Front bridge frame, 33A: Bearing portion,
34: bracket, 35: inner shell, 35A: string groove, 36: cushioning material,
37: Lifting lever, 38: Cavity, 39: Screw hole, 40: Backrest support member, 41: Rear bridge frame, 42: Back shell mounting portion, 43: Flange, 44: Bearing portion,
45: Arm portion, 47: Bracket, 48: Armrest mounting base 50: Backrest 51: Back shell, 52: Back plate, 52A: Step, 52B: Flange,
53: back frame, 53A: groove, 53B: fitting portion, 53C: rear support portion,
54: Cushioning material,
55: Headrest, 55A: Main body, 55B: Fixing part,
56: Back mounting seat,
56A: groove for flange, 56B: groove for front upholstery, 56C: groove for back upholstery,
56D: vertical rib, 56E: female screw 60: armrest 61: armrest body, 62: frame-shaped portion, 62A: opening,
62X: Inner opening surface, 62Y: Outer opening surface,
63: connecting arm, 64A-64D: core material, 65: recessed hole, 66: panel,
67: inner surface material, 68: outer surface material, 69: shoulder screw, 80: fixing screw, 90: armrest, 100: chair, SJ: backrest rotation axis, W: operating wire, WT: ball part

Claims (6)

An armrest body attached to a chair body and having a frame-shaped portion;
a panel attached to the opening of the frame-shaped portion;
At least one first engaging portion is disposed on an inner circumferential surface of the opening,
A second locking portion that is paired with the first locking portion is provided on the outer circumferential surface of the panel ,
the first engaging portion is a recess which is a machined hole, and the second engaging portion is a protrusion formed by a large diameter portion and a screw head portion of a shoulder screw standing on the outer peripheral surface of the panel;
Alternatively, the armrest is characterized in that the first engagement portion is a convex portion formed by the thick-diameter portion and the head portion of a shoulder screw raised on the inner surface of the opening, and the second engagement portion is a concave portion which is a machined hole . 2. The armrest according to claim 1, wherein a screw is screwed from the outer peripheral surface of the frame-shaped portion to the frame-shaped portion at a position opposite to the positions at which the first and second locking portions are disposed. The first engaging portion is disposed on a lower side, a front side, or a rear side of the inner circumferential surface of the opening,
The second engaging portion is disposed on the lower side, the front side, or the rear side of the outer circumferential surface of the panel,
3. The armrest according to claim 2 , wherein the screws are covered by a cover attached to the outer circumferential surface of the frame-shaped portion. The armrest according to any one of claims 1 to 3 , characterized in that the opening is formed in a frustum shape that gradually narrows from the seat side toward the outside. 5. The armrest according to claim 4, wherein the panel has an inner surface material that is the surface facing the seat and an outer surface material that is the outer surface, the outer surface having a different outer diameter. A chair comprising an armrest according to any one of claims 1 to 5 .

Images