JP2010269065A - Chair and armrest device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an armrest device which can reliably be attached. <P>SOLUTION: The armrest device 13 has an elbow support 14 and a boss portion 34 provided at the tip of the elbow support 14 is fitted into an elbow receiving concavity 19 of a back frame 8. A taphole 35 penetrates the boss portion 34 from top to bottom and a machine screw 25 is turned into the taphole 35. A nut retaining groove 37 nonrotatably retaining the nut 36 is formed on the top face of the boss portion 34. Even if the thread of the taphole 35 is crushed for some reason, the elbow support 14 can be fixed to the back frame 8 by turning the machine screw 25 into the nut 36. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a chair and an armrest device used therefor, and in short, relates to an elbow post mounting structure.

  The armrest device is often an optional item for the chair, and therefore, it can be easily retrofitted to the chair body. Here, examples of the chair main body to which the armrest device is attached include a seat receiving member such as a seat outer shell, a base fixed to the upper end of the leg device, and a back frame to which the backrest is attached.

  The armrest device is fastened to the main body with a screw. However, since the armrest device is subjected to a considerable load, high mounting strength is required, and ease of positioning is also required for mounting. In this regard, Patent Documents 1 and 2 describe that the boss portion of the elbow post is fitted into the elbow receiving recess of the chair body. When this structure is adopted, the fitting between the boss portion and the elbow receiving recess is described. A high mounting strength can be secured by the interference. Further, Patent Document 3 describes that a lateral boss portion is provided on the back frame and a concave portion of the elbow post is fitted into the boss portion. In this case, it can be said that high attachment strength can be ensured.

  In each patent document, the elbow strut is fixed to the back frame with a screw. However, in Patent Document 1, as a fastening structure using a screw, a screw (bolt) is screwed into a nut that is non-rotatably held in a boss. In 2 and 3, a tapped hole is made in the back frame and a screw is screwed into this.

JP 2008-104543 A JP 2006-102129 A JP 2007-190220 A

  Since the fastening structure using a nut and the fastening structure using a tapped hole exhibit a fastening function, the industry does not require a tapped hole when using a nut, and a nut when using a tapped hole. Is recognized as unnecessary.

  On the other hand, the elbow struts that make up the armrest device often use aluminum die-cast products and resin molded products, and the back frame and seat receiving members for mounting the armrest devices also use aluminum die-cast products and resin molded products. However, aluminum die-cast products and resin molded products have the advantage of being excellent in moldability and aesthetics, but have the property of being inferior in strength compared to iron. If the screw is strongly screwed in, the screw thread may be crushed or the tapping may be incomplete and the screw may not be caught sufficiently, which may make the fastening impossible. In particular, when tapped holes are made in the back frame as in Patent Documents 2 and 3, if the thread of the tapped hole is crushed, the armrest device cannot be attached unless the back frame is replaced. The problem is serious when the crushed.

  The present invention has been made to improve the current situation.

  The present invention is directed to a chair and an armrest device. The inventions according to claims 1 to 3 relate to a chair. This chair has a “chair body part and an armrest device, and the chair body part is provided with an elbow receiving recess that opens outward in the left-right direction. On the other hand, the elbow strut constituting the armrest device is formed with a boss portion that fits into the elbow receiving recess.

  And in invention of Claim 1, while the screw insertion hole is vacated in the appropriate location around the elbow receiving recess, the screw inserted into the screw insertion hole is screwed into the boss portion of the elbow post. A tapped hole and a nut holding portion that holds a nut that can be screwed into the screw protruding from the tapped hole are held non-rotatably.

  The invention of claim 2 embodies the invention of claim 1, and this invention is further connected to the base fixed to the upper end of the leg support and to the base so as to be able to tilt backward. And a back frame to which a backrest is attached, the elbow receiving recess is formed in the back frame, and the screw is inserted into the back frame from substantially below and screwed into the tap hole of the boss portion. It is supposed to be.

  The invention of claim 3 embodies the invention of claim 2, and in this invention according to claim 2, the elbow post and the back frame are die-cast aluminum or a resin molded product, and the nut holding portion is It is formed on the upper surface of the boss part and opens toward the tip of the boss part, while the back part of the elbow receiving recess in the back frame is fitted to the nut holding part of the boss part and the nut is A stopper for positioning from the back side is formed.

  The invention of claim 4 relates to an armrest device, and this invention has an elbow strut and an elbow rest supported by the elbow strut. A boss portion that fits into the elbow receiving recess of the direction opening is provided, and a tapped hole into which a screw inserted from the outside into the peripheral wall surrounding the elbow receiving recess is screwed into the boss portion, and a screw protruding from the tap hole And a nut holding portion that can hold the nut that can be screwed in a non-rotatable manner.

  In the present invention, not only can the elbow strut be fastened to the elbow receiving recess by screwing the screw into the tapped hole, but the screw thread of the tapped hole is crushed or the tapping is incomplete. Even if it becomes impossible, the elbow post can be fastened to the elbow receiving recess by screwing the screw into the nut.

  In other words, even when the tap hole becomes malfunctioning, the nut substitutes for the function, and thus it is possible to continue to secure the mounting function of the armrest device. The armrest device can be installed by the user, but the user is often unfamiliar with the work. Is done. Therefore, it can be said that the effect of the present invention is exerted strongly when the user attaches the armrest device.

  From the viewpoint of only the fastening function of the elbow strut, it can be said that it is common to make a tap hole in the back frame (chair body) as in Patent Documents 2 and 3. When a tapped hole is drilled in the back frame in this way, if a nut is placed as a measure when the thread of the tapped hole is crushed, the nut is placed on the opposite side of the elbow strut across the tapped hole in the back frame. I have to do something. However, since a large load is applied to the back frame when locking it, there is a risk that the strength may be reduced if a tapped hole or nut mounting part is formed on the back frame. In the case where the nut is attached in advance, there is a high possibility of structural waste or loss of the nut.

  On the other hand, in the present invention, a tapped hole is provided in the elbow strut and a nut holding portion is provided in the elbow strut. Therefore, the main body portion such as the back frame is caused by providing the tap hole and the nut holding portion. There is no decrease in strength. This is also a great advantage of the present invention.

  The screwing direction of the screw can be arbitrarily set according to the structure of the elbow receiving recess. However, when the screw is screwed into the elbow strut from below as in claim 2, the screw insertion hole in the head of the screw and the elbow receiving recess is not visible. There is an advantage that it is excellent in aesthetics. In the invention of claim 3, since the nut is also positioned by a stopper formed in the elbow receiving recess, the nut can be firmly held in a non-rotatable state to ensure screw screwing.

  As described above, the elbow post and the back frame often use a molded product such as a die-cast product or a resin molded product. This molded product is manufactured using a mold that can be adhered and separated freely, and therefore, it must be shaped and structured as easily as possible from the viewpoint of cost and manufacturing efficiency. The invention of claim 3 ensures the positioning of the nut while ensuring the ease of die cutting (the details of this point will be described based on the embodiment).

It is a side view of the chair concerning an embodiment. (A) is the perspective view which looked at the principal part from the inside, (B) is the perspective view which looked at the principal part from the outside. (A) is the isolation | separation perspective view of the principal part, (B) is the perspective view which looked at the principal part from the downward direction. (A) is the partial perspective view of a back frame, (B) is the perspective view which looked at the elbow strut from the lower part, (C) is the partial perspective view which looked at the elbow strut from the top. (A) is a partially broken plan view of the main part, (B) is a sectional view taken along line XX of (A) with the screw separated, and (C) is (A) with the screw screwed into the nut (A) FIG.

  Next, an embodiment of the present invention will be described with reference to the drawings. This embodiment is applied to a swivel chair with a locking function that is frequently used for office work or the like. In the following description, the term “left and right” is used as a term for specifying the direction, and this is based on a seated person.

(1). Outline of Chair As shown in FIG. 1, the chair is provided with a leg device 2 having a leg column (gas cylinder) 1, a base 3 fixed to the upper end of the leg column 1, and an upper part of the base 3. And a backrest 5 disposed on the rear side of the seat 4. The seat portion 4 has a resin outer shell (seat support) 6, and a seat with a cushion on the inner shell (seat plate) is supported by the outer shell (seat support) 6.

  Although not shown in detail, the backrest 5 has a structure in which a mesh member is stretched on a frame 7 that is a quadrangle when viewed from the front, and the frame 7 is fixed to a pair of left and right back frames 8. The back frame 8 has a base portion 9 extending substantially rearward from the left and right outer sides of the base 3 and an upright portion 10 rising from the rear end thereof. The backrest 5 is mainly attached to the upright portion 10. In a neutral state where the person does not lean on the backrest 5, the base 9 of the back frame 8 is in a backward inclined posture with respect to the horizontal in a side view, and the upright portion 10 is in a forward inclined posture with respect to the vertical line. A headrest device 11 is attached to the frame 7 of the backrest 5.

  The front portion of the outer shell 6 constituting the seat portion 4 is connected to the base 3 by a front link 12 so as to be relatively rotatable, and the rear portion of the outer shell 6 is slidable substantially back and forth relative to the back frame 8. Connected as possible. Therefore, when the seated person leans against the backrest 5, the seat portion 4 tilts backward while moving backward in conjunction with the backrest 5. The backward tilting of the back frame 8 is elastically supported by a torsion bar as an example of a spring means.

  In this embodiment, armrest devices 13 are attached to the left and right back frames 8. The armrest device 13 includes an elbow post 14 fixed to the back frame 8 and an elbow rest 15 attached to the elbow post 14 so as to be movable up and down. Next, the mounting structure of the elbow strut 14 will be described with reference to the drawings of FIG.

(2). Structure of the back frame / armrest device Both the back frame 8 and the elbow support 14 are aluminum die-cast products, and as shown in FIG. It has a shape, and a number of reinforcing ribs 17 are provided inside. In addition, a long hole 18 into which a slider (not shown) attached to the outer shell 6 of the seat portion 4 is fitted inwardly opens in the base portion 9 of the back frame 8. As can be easily understood from the structure of the back frame 8, the back frame 8 is roughly manufactured by using a main mold that relatively moves in the left-right direction (a split mold or a pin is attached to the main mold). is doing.).

  The base 9 of the back frame 8 is formed with an elbow receiving recess 19 that opens to the left and right outside. For example, as shown in FIG. 4, the elbow receiving recess 19 has a substantially square shape (diamond) in a side view, and a step 20 is formed in the opening. The elbow receiving recess 19 has a pocket shape. As shown in FIG. 5, the elbow receiving recess 19 includes an upper plate 21, a back plate 22, front and rear side plates 23, and a bottom plate 24.

  A screw insertion hole 26 through which the screw 25 is inserted from below is opened at approximately the center of the bottom plate 24. The screw insertion hole 26 has a large-diameter portion (a counterbore portion) where the head of the screw 25 is hidden. In order to secure the depth of the elbow receiving recess 19 without increasing the left and right thickness of the back frame 8, the elbow receiving portion having the elbow receiving recess 19 protrudes outward in the left and right directions. As can be easily guessed from each drawing, the elbow receiving recess 19 is open in the die-cutting direction, and a mold for forming the outer surface of the back frame 8 has a projection for forming the elbow receiving recess 19. Is formed.

  The elbow strut 14 is formed in an L shape by a substantially horizontally long base portion 27 and a substantially vertically long standing portion 28, and an elevating cylinder 29 is fitted to the standing portion 28 so that the height can be adjusted. The elbow rest 15 is fixed to the lifting cylinder 29, and a lever 30 for releasing the height adjustment lock is provided at the upper end of the lifting cylinder 29.

  Further, for example, as shown in FIG. 3A, a vertical groove 31 that opens forward is formed in the standing portion 28 of the elbow post 14, and the vertical groove 31 is a rib for adjusting the height of the elbow rest. Is formed in multiple stages. In addition, escape grooves 32 for stealing meat are formed in multiple stages on the left and right side surfaces of the rear portion of the standing portion 28.

  A boss portion 34 that fits into the elbow receiving recess 19 of the back frame 8 is formed at the tip of the base portion 27 of the elbow strut 14. The boss part 34 is formed in the base part 27 in a state of being slightly smaller, and the base part 27 a of the boss part 34 is fitted into the step part 20 of the elbow receiving recess 19. For this reason, the elbow strut 14 is fitted with a high strength and no backlash with respect to the back frame 8.

  The boss portion 34 of the elbow strut 14 has a tap hole 35 into which the screw 25 is screwed up and down, and a nut 36 into which the screw 25 is screwed is rotated on the upper surface of the boss portion 34. A nut holding groove 37 is formed as an example of a nut holding portion that cannot be accommodated. The nut 36 is a commercially available hex nut. The nut holding groove 37 is cut and opened toward the tip of the boss portion 34, and the opening is formed with a tapered portion 37a that widens toward the tip in plan view.

  Further, the nut holding groove 37 holds the nut 36 in such a posture that its two apexes are located on the left and right sides, and accordingly, the inner portion of the nut holding groove 37 (the end portion located at the standing portion 28 of the elbow post 14). ) Is V-shaped in plan view. Since the tap hole 35 is formed at approximately the center portion of the boss portion 34 and the nut holding groove 37 is a cut-opening method, the nut 36 can be displaced in the left-right direction. Therefore, as shown in FIGS. 4A and 5, a stopper 41 for positioning the nut 36 is provided in the elbow receiving recess 19 of the back frame 8. The stopper 41 has a V-shaped tip in plan view, and is integrally connected to the upper plate 21 and the back plate 22 constituting the elbow receiving recess 19.

  For example, as shown in FIG. 4B, a downward recess 38 is formed on the lower surface of the base 27 of the elbow strut 14 to save material, and the downward recess 38 is shown in FIG. 3B. Covered with a cover 39. For example, as shown in FIG. 4B, the boss portion 34 is formed with a relief groove 40 for equalizing the thickness and ensuring accuracy. The tap hole 35 may be processed by forming a pilot hole and then tapping, or may be processed at the time of forming by using a rotary rack (in the case of die casting, post-processing) It can be said that there are many.)

(3) Summary The elbow support 14 is fixed to the base 9 of the back frame 8 by screwing the screw 25 after fitting into the elbow receiving recess 19 of the back frame 8. In this case, when the boss portion 34 is fitted into the elbow receiving recess 19, the armrest device 13 is held so as not to drop, and therefore it is not necessary to hold the armrest device 13 by hand when screwing the screws 25. Easy installation and removal. Further, as described above, since the elbow strut 14 is also fitted in the step portion 20 of the elbow receiving recess 19, the support strength of the elbow strut 14 can be improved.

  As long as the tap hole 35 of the boss portion 34 is functioning, the elbow strut 14 is fastened (fixed) to the back frame 8 by screwing the screw 25 into the tap hole 35. On the other hand, when the thread of the tap hole 35 is crushed for some reason, the elbow strut 14 can be fastened to the back frame 8 by screwing the screw 25 into the nut 36. The nut 36 may be set in the armrest device 13 in advance, or the user may purchase and use a commercially available product when the tap hole 35 is crushed.

  FIG. 5C shows a state in which the screw 25 is screwed into the nut 36. However, when the nut 36 is set in advance with the tap hole 35 functioning, the screw 25 is a nut. A length that does not reach 36 may be used. That is, the screws 25 having different lengths may be selectively used when the nut 36 is used and when the nut 36 is not used.

  It is also possible to set the nut 36 in advance and screw the screw 25 into the nut 36 while screwing it into the tap hole 35. However, the end of the female screw of the tap hole 35 is not necessarily coincident with the starting end of the female screw of the nut 36. Therefore, generally, when the nut 36 is raised, the screw 25 can be screwed into the nut 36. Therefore, if a clearance is provided between the bottom surface of the nut holding groove 36 and the upper plate 21 of the elbow receiving recess 19 so that the nut 36 can be lifted at least by the pitch of the screw, the fastening using the tap hole 35 is possible. Fastening using the nut 36 can be performed with a single screw 25.

  As described above, the back frame 8 is manufactured by using a main mold that relatively moves in the left-right direction. On the other hand, the main mold that moves in the left-right direction is also used in the manufacture of the elbow struts 14, and the vertical groove 31 is processed by a slide mold that moves in the front-rear direction. A slide mold that moves up and down is used to form the downward recess 38. The nut holding groove 37 can be formed in a hexagonal shape in a plan view opened only upward, but in this case, another slide mold for forming the nut holding groove 37 is required, and the cost is accordingly increased. Bulky.

  Therefore, in the present embodiment, the nut holding groove 37 is cut open toward the tip of the boss portion 34, thereby eliminating the need for a special slide mold for forming the nut holding groove 37 and the back frame 8. The nut 36 is positioned by providing a stopper 41 in the elbow receiving recess 19. Since the stopper 41 can be molded without using a special slide mold, the mold apparatus is not excessively complicated due to the provision of the stopper 41. Accordingly, the nut 36 can be accurately positioned without excessively complicating the mold apparatus for manufacturing the back frame 8 and the elbow support 14.

  As a method of manufacturing the elbow strut 14, a main mold that relatively moves in the front-rear direction may be used. In this case, the nut holding groove 37 and the relief groove 40 are simultaneously formed by a slide mold that moves left and right. be able to. Accordingly, in this case as well, it is possible to prevent the mold apparatus for manufacturing the elbow strut 14 from becoming excessively complicated. When the tapered portion 37a is formed at the tip of the nut holding groove 37, there is an advantage that the fitting with the stopper 41 is guided.

(4). Others The present invention can be embodied in various ways other than the above embodiment. For example, the present invention and the shape of the elbow receiving recess can be arbitrarily set as necessary, and the boss portion and the elbow receiving recess can be formed to have, for example, a circular cross section or an elliptical shape. Further, it goes without saying that the present invention can also be applied to a type in which the elbow rest does not move up and down, and therefore the elbow rest may be provided integrally with the elbow strut.

  Further, the portion where the elbow receiving recess is provided is not limited to the back frame, but can be provided on the base fixed to the state of the outer shell or the leg column constituting the seat. It is possible to use a plurality of screws, and the screwing direction (insertion direction) of the screws can be selected according to the structure of the elbow receiving portion.

  The present invention is applied to a chair and exhibits its usefulness, and thus has industrial applicability.

2 leg device 4 seat 5 backrest 8 back frame 9 base of back frame 13 armrest device 14 elbow strut 15 elbow rest 19 elbow receiving recess 24 bottom plate 25 screw (bolt)
26 Screw insertion hole 27 Base of elbow post 34 Boss 35 Tap hole 36 Nut holding groove 41 Stopper

Claims (4)

A chair body and an armrest device, and the chair body is provided with an elbow receiving recess that opens outward in the left-right direction, while the elbow support recess constituting the armrest device has the elbow receiving recess The boss part that fits in is formed,
While a screw insertion hole is vacated at an appropriate location around the elbow receiving recess, a boss portion of the elbow strut has a tap hole into which a screw inserted into the screw insertion hole is screwed, and protrudes from the tap hole A nut holding portion for holding a nut that can be screwed into a non-rotatable nut,
Chair. The base further includes a base fixed to the upper end of the leg post, and a back frame connected to the base so as to be tiltable backward and having a backrest attached thereto. The elbow receiving recess is formed in the back frame. The screw is inserted into the back frame from substantially below and screwed into the tap hole of the boss part.
The chair according to claim 1. The elbow strut and the back frame are aluminum die cast or a resin molded product, and the nut holding portion is formed on the upper surface of the boss portion and opens toward the tip of the boss portion, while the elbow support in the back frame At the back of the recess, a stopper is formed to fit the nut holding part of the boss part and position the nut from the back side.
The chair according to claim 2. An elbow strut and an elbow rest supported by the elbow strut, and the elbow strut is provided with a boss portion that fits into an elbow receiving recess of a left and right outward opening provided in the chair main body, The boss portion is provided with a tap hole into which a screw inserted from the outside into the peripheral wall surrounding the elbow receiving recess is screwed, and a nut holding portion capable of holding a nut capable of screwing the screw protruding from the tap hole in a non-rotatable manner. ing,
Chair armrest device.

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