JP2013144014A - Structure for mounting optional member to backrest of chair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily attach an optional member to a backrest, a shape of a frame member in the backrest is not limited for the attachment of the optional member, and a connecting portion between the optional member and the backrest is provided. Provided is a structure for attaching an optional member to a backrest of a chair, which does not obstruct a seated person, and further allows the optional member to be attached at an arbitrary position on the back of the backrest.
An option member 10 is attached to a backrest 9 of a chair, and a receiving member 17 having a protrusion protruding rearward is attached to the back surface of the backrest 9, and the protruding portion of the receiving member 17 is A holding member 18 that holds the option member 10 is attached.
[Selection] Figure 3

Description

  The present invention relates to a structure for attaching an optional member to a backrest of a chair.

  As an attachment structure for attaching optional members such as hangers and headrests to the backrest of the chair, for example, a state where a pair of left and right support rods supporting the hangers are in contact with the rear surface of the rear frame provided on the upper rear surface of the backrest Then, the rear frame and both support rods are sandwiched from the front and rear by a plate-like mounting member and a screw seat piece facing in the left-right direction, and the mounting member and the screw seat piece are fastened by screws (for example, Patent Document 1). reference).

  In addition, a hanger support column is inserted between the block-shaped base part attached to the rear part of the backrest and a holding plate attached with a gap behind the base part so as to be movable up and down, and the base part and the presser plate Are covered with a cover, and the hanger column is sandwiched between a locking protrusion that protrudes rearward from the base part and a protrusion of the cover that protrudes forward from the round hole of the pressing plate. (For example, refer to Patent Document 2).

  Further, a groove is provided in the upper frame collar of the frame member in the backrest, and the upper frame portion of the back frame is formed by the main body attachment portion and the holding piece so that the opposing portion of the main body attachment portion is fitted in this groove. By sandwiching them from above and below and screwing them, the headrest which is an optional member is fixed to the backrest (for example, see Patent Document 3), on the lower surface of the upper frame collar of the frame member in the backrest, There are those in which a hanger is suspended through a suspension member (for example, see Patent Document 4).

JP 2006-110013 A JP 2004-174145 A JP 2008-104521 A JP 2011-045572 A

  In the ones described in Patent Documents 1 and 2, when the optional member is attached to the backrest, the optional member is held by hand in a state of being in contact with the upper frame collar of the backrest, and the mounting work Since this has to be done, the work is cumbersome and man-hours increase.

In the thing described in patent document 3, since the groove | channel must be provided in the upper frame collar of the frame member in a backrest, the shape of the frame member in a backrest is only restrict | limited for attachment of an option member Rather, it requires two workers, one that holds them in the state where the upper frame part of the back frame is sandwiched from above and below by the main body mounting part and the holding piece, and the person who screws them, Similar to those of Patent Documents 1 and 2, the mounting work is troublesome and the number of man-hours increases.
In addition, after completion of the attachment of the option member, the main body attachment portion and the gripping piece may protrude forward from the frame member, and depending on the size, there is a risk of hitting the seated person's back.

  In the thing of patent document 4, since a hanger is located below the upper frame collar of a backrest, it is difficult to attach or detach clothes to the hanger, and an optional member disposed above the backrest like a headrest, etc. Not applicable for installation.

  The present invention has been made in view of the above problems, and the optional member can be easily attached to the backrest, and the shape of the frame member in the backrest is not limited for the attachment of the optional member. In addition, the joint between the optional member and the backrest does not hinder the seated person, and the optional member can be attached to any position on the back of the backrest. An object of the present invention is to provide an attachment structure for an optional member.

According to the present invention, the above problem is solved as follows.
(1) In the attachment structure of the optional member for the backrest of the chair, a receiving member having a protrusion protruding backward is attached to the back surface of the backrest, and the optional member is held by the protrusion of the receiving member Attach the holding member.

With such a configuration, the receiving member is attached in advance to the back of the backrest, and then the holding member that has previously held the optional member is attached to the protrusion of the receiving member, or the protrusion is By attaching the holding member to the holding member and then holding the option member, the option member can be easily and neatly attached to the backrest, and work efficiency can be improved.
Further, the optional member can be attached to any shape of the backrest, and the shape of the backrest is not restricted for the attachment of the optional member, and the optional member can be attached to the back of the backrest. The attachment position is not limited, and the optional member can be attached to any part.
Furthermore, since both the receiving member and the holding member are attached to the back side of the backrest, the receiving member and the holding member do not protrude forward of the backrest, and there is no possibility of hitting the back of the seated person.

  (2) In the above item (1), a receiving hole that opens upward is provided on the upper surface of the protrusion of the receiving member, and a downwardly provided insertion portion provided on the lower surface of the front portion of the holding member is provided in the receiving hole. The holding member is attached to the receiving member by fitting.

  (3) In the above item (1) or (2), a projection projecting upward is provided on the upper surface of the projection of the receiving member, and the projection is fitted upwardly on the lower surface of the holding member. Fits into the recess.

  With the configuration as described in the above item (2) or (3), the holding member can be easily coupled to the receiving member by simply lowering the holding member from above the protruding portion on the receiving member. Can improve sex.

  (4) In any one of the above items (1) to (3), the upper surface of the front portion of the receiving member is brought into contact with the lower surface of the mounting portion constituting a part of the backrest, and the receiving member is attached to the mounting portion. Stick.

  With such a configuration, the joint portion between the backrest and the receiving member is difficult to be exposed to the outside, so the appearance is good.For this reason, the lateral width of the joint portion is increased to ensure the joint area and to increase the joint strength. Even if it is increased, the appearance is not deteriorated.

  (5) In the item (4), the receiving member is fixed to the mounting portion by bringing the front surface of the rising portion standing from the rear of the upper surface of the front portion of the receiving member into contact with the rear surface of the mounting portion.

  With such a configuration, the receiving member is in a state where the upper surface of the front part of the receiving member is in contact with the lower surface of the mounting part of the backrest and the front surface of the standing part of the receiving member is in contact with the rear surface of the mounting part. Since it is fixed to the backrest mounting portion, the coupling strength of the receiving member in the vertical direction and the front-rear direction with respect to the backrest mounting portion is increased, and the optional member can be stably held.

  (6) In the above item (5), the upright portion of the receiving member is fixed to the rear surface of the mounting portion with a fixing screw facing in the front-rear direction, and the holding member is fixed to the protruding portion of the receiving member in the up-down direction It sticks with.

  With such a configuration, the receiving member can be screwed to the mounting portion of the backrest in an easy posture from behind using the space behind the backrest, and after that, Using the space above and below the protrusion, the holding member can be screwed to the protrusion of the receiving member in an easy posture, and the attachment workability of the optional member can be improved.

  According to the present invention, the optional member can be easily attached to the backrest, the shape of the frame member in the backrest is not restricted for the attachment of the optional member, and the option member and the backrest are coupled. It is possible to provide a structure for attaching an optional member to a backrest of a chair, in which an optional member can be attached to an arbitrary position on the back surface of the backrest without causing the seat to interfere with the seated person. it can.

It is a side view of a chair provided with one embodiment of the present invention. It is the perspective view which looked at the backrest of the chair from diagonally right rear. It is the III-III line enlarged vertical side view of FIG. It is the disassembled perspective view which looked at the receiving member and the holding member from diagonally forward right. It is the VV line expansion longitudinal end view of FIG. FIG. 6 is a cross-sectional plan view taken along line VI-VI in FIG. 3. It is a disassembled perspective view for demonstrating the procedure which attaches a receiving member, a holding member, and an option member to a backrest. FIG. 8 is a longitudinal end view taken along line VIII-VIII in FIG. 6. It is the IX-IX line enlarged vertical end view of FIG.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each figure, the left and right are referred to in front view.
FIG. 1 is a side view of a chair provided with an embodiment of the present invention.
The chair has a leg 3 having five radial rods 2 each having a caster 1 at the tip, and a telescopic member that is erected at the center of the leg 3 and accommodates a gas spring (not shown). Pedestal 4, a support base 5 facing the front upper side with the rear end fixed to the upper end of the pedestal 4, a seat 6 supported above the support base 5, and an axis with the front end facing the left-right direction 7, a backrest 9 supported on the rear upper part of the back support frame 8 having a substantially L-shape in a side view and pivotally attached to the support base 5; Device 10.

  In addition, since the components other than the backrest 9 and the hanger device 10 are not directly related to the present invention, the specific configuration and detailed description thereof will be omitted.

As shown in FIG. 2, the backrest 9 includes a back frame 11 made of a hard synthetic resin that is a frame body having a substantially square front shape, and a tension member 12 stretched on the front surface of the back frame 11. .
The upholstery material 12 is formed in a square shape by a mesh material, a woven fabric, a canvas, etc., and the outer periphery thereof is sewn, tackered, bonded, or other fastening means so as to cover the front surface of the back frame 11. It is fixed to the outer peripheral edge of the frame 11.

The back frame 11 has a pair of left and right side frame ridges 13 and 13 that are gently bent in a U shape so that a portion slightly below the center in the vertical direction protrudes forward in a side view, and upper ends thereof are The upper frame rod 14 that gently curves in an arc shape and the lower end portions of both side frame rods 13 and 13 are coupled to each other and directed downward. And a lower frame rod 15 that curves so as to protrude. The upper frame rod 14 has an upper auxiliary frame member 14a (see FIG. 3) fixed to the back surface with a fixing screw (not shown).
The upper portion of the upholstery material 12 passes through the upper surface from the front surface of the upper frame collar 14, and is then wound around the upper surface, the rear surface, the lower surface, and the front surface of the upper auxiliary frame material 14a. It is attached to the back frame 11 so as to be sandwiched between the rear surface of the upper frame collar 14.

  A pair of left and right forward pieces 16 connected to the back support frame 8 are provided on the lower frame collar 15 of the back frame 11.

Next, the hanger device 10 which is an optional member will be described. As an optional member, in addition to the hanger device 10, an appropriate member such as a headrest can be selected.
The hanger device 10 is attached to the upper frame collar 14 of the back frame 11 by a receiving member 17 and a holding member 18.
2 and 3, the hanger device 10 includes a hanger body 19 facing in the left-right direction, a pair of left and right support rods 20 extending downward from the hanger body 19, and a pair of left and right support rods. 20 is provided with a connecting rod 21 for connecting the lower ends of the two.
The pair of left and right support rods 20 in the hanger device 10 are attached to the holding member 18 so that the vertical position can be adjusted.

  The hanger body 19 extends in the left-right direction to such a length that a suit or the like can be hung, and has a shape in which a central portion is gently curved downward and both side portions are gently inclined downward in a front view.

  The pair of left and right support rods 20 are each composed of a vertical rod portion 20a in the vertical direction and curved portions 20b that are separated from each other in the left and right direction upward from the upper end of the vertical rod portion 20a. Are connected by a connecting rod 21 that gently curves so as to protrude downward.

  As shown in FIGS. 3 and 4, the receiving member 17 has a protrusion 17 a that protrudes rearward from the upper frame collar 14 of the back frame 11, and projects forward from the lower front surface of the protrusion 17 a. It consists of the front part 17b located below.

A step portion 22 between the protrusion 17 a and the front portion 17 b of the receiving member 17 is fitted to a corner portion of the rear lower end of the upper frame collar 14 of the back frame 11.
On the upper surface of the front portion 17 b of the receiving member 17, a plurality of lightening holes 23 opening upward and a plurality of ribs 24 facing in the front-rear direction for partitioning each lightening hole 23 are provided side by side in the left-right direction. It has been.

Further, the upper surface of the front portion 17b of the receiving member 17 has a concave groove 25 that opens upward and continues in the left-right direction so as to penetrate both side walls of the front portion 17b and the ribs 24, and left and right 1 A pair of upward projections 26, 26 are provided.
As shown in FIGS. 3 and 5, when the receiving member 17 is attached to a regular attachment position in the upper frame collar 14 that is an attachment portion of the optional member in the back frame 11, the concave groove 25 in the receiving member 17 is It fits into the downward projection 14b provided at the lower rear edge of the upper frame rod 14, and the upward projection 26 fits into a pair of left and right upward recesses 14c provided at the front lower surface of the upper frame rod 14. It is supposed to be.

A pair of left and right screw insertion holes 28 facing in the front-rear direction are provided in the upper portion of the upright portion 27 that forms the front wall of the protrusion 17a and rises from the rear of the upper surface of the front portion 17b of the receiving member 17.
A thick portion 27a is formed between the left and right screw insertion holes 28, 28 on the rear surface of the upright portion 27. The upper end surface of the thick portion 27a has a bottom with a long side that opens upward. The receiving hole 29 is provided.
On the rear surface of the thick portion 27a, there is provided a slit 30 that communicates with the receiving hole 29 and faces in the vertical direction.

  The protrusion 17a in the receiving member 17 includes the upright portion 27 forming the front wall, the bottom wall 31 inclined from the lower end toward the rear upper side, and both side walls 32 and 32, and opens upward and rearward. It is almost a hollow box.

  On the rear surface of the thick portion 32a formed on the rear inner surface of each side wall 32, there is provided a vertical receiving groove 33 that opens rearward and upward and the depth of the groove gradually decreases downward. ing.

The rear end of the upper surface of the bottom wall 31 is provided with a protruding portion 34 that protrudes upward in the left-right direction. Similarly, behind the receiving hole 30, a pair of left and right screw insertion holes 35 that face in the up-down direction. Is provided.
Since the drawing direction of the mold of the receiving member 17 may be only the vertical direction, the manufacturing is easy.

  The holding member 18 has a substantially rectangular upper plate portion 36 whose planar shape covers the upper surface of the projection 17a of the receiving member 17, a rear wall portion 37 (see FIG. 3) that hangs down from the rear end portion of the upper plate portion 36, And a plate-like insertion portion 38 facing in the left-right direction depending on the front lower surface of the upper plate portion 36. A vertical rib 39 (see FIG. 6) that faces in the front-rear direction is provided between the center portion in the left-right direction on the rear surface of the insertion portion 38 and the rear wall portion 37.

  As shown in FIG. 9, a pair of left and right cylindrical bosses 40 (see FIG. 6) located behind the insertion portion 38 are provided on the lower surface of the upper plate portion 36. Each hole 41 is provided. A rib 42 is provided between the boss 40 and the rear wall portion 37. At the rear ends of the lower ends of the ribs 42 and the ribs 39, upward fitting recesses 42a and 39a that are complementary to the upward protruding portions 34 of the receiving member 17 are provided.

  As shown in FIG. 4, thick wall portions 43 (see FIG. 6) that protrude forward are provided at the left and right ends of the rear wall portion 37. The thick portion 43 is provided with a fitting groove 44 that opens in the upward and downward direction and extends through the upper plate portion 36. As will be described later, the fitting groove 44 is fitted with a protrusion 20 c that is provided on the inner surface of the support rod 20 of the hanger device 10 and faces in the vertical direction.

  On the front edge of the opening to the outer surface of the fitting groove 44 in the holding member 18, there is a rearward protrusion 46 having a dog-shaped engagement groove 45 in which the central part in the vertical direction is recessed forward. Is provided. The front end portion of the rearward projecting portion 46 projects forward from the thick portion 43.

  As shown in FIG. 5, the front surface of the vertical protrusion 20 c provided on the inner surface of the support rod 20 in the hanger device 10 fitted in the fitting groove 44 has a dogleg shape in the fitting groove 44. And a plurality of engaging portions 47 that are complementary to the engaging concave groove 45 are provided in the up and down direction, and a corrugated portion 48 that faces in the up and down direction is provided.

As shown in FIG. 6, on the front surface of the ridge 20 c of each support rod 20, a fitting concave groove 49 that has a corrugated portion 48 as a bottom surface and opens toward the front is provided. A rearward protruding portion 46 having a dog-shaped engaging groove 45 in the holding member 18 is fitted into the fitting groove 49 so as to engage with the engaging portion 47 of the corrugated portion 48. Yes.
The front end portion of the rearward protruding portion 46 is fitted in the receiving groove 33 in the left and right side walls 32 of the receiving member 17.

  The hanger device 10 can adjust the vertical position with respect to the holding member 18 by changing the plurality of engaging portions 47 of the corrugated portion 48 that engages with the engaging concave groove 45. The vertical position adjustment of the hanger device 10 with respect to the holding member 18 will be described later.

  To attach the hanger device 10 to the backrest 9, as shown in FIG. 7, the receiving member 17 is approached from the rear to the upper frame ridge 14 of the backrest 9, and as shown in FIGS. 3 and 5, The concave grooves 25 in the member 17 are fitted into the downward protrusions 14b on the lower surface rear edge of the upper frame flange 14, and the upward protrusions 26 are formed in a pair of left and right upward recesses 14c in the lower surface front portion of the upper frame flange 14. The upper surface of the front portion 17b of the receiving member 17 is brought into contact with the lower surface of the upper frame rod 14 so as to be fitted, and the front surface of the standing portion 27 of the receiving member 17 is brought into contact with the rear surface of the mounting portion of the upper auxiliary member 14a. 6 and 8, the fixing screw 50 is inserted into the screw insertion hole 28 in the standing portion 27, and the screw hole 51 is provided at a corresponding position on the rear surface of the upper auxiliary frame member 14a. Screw in and tighten.

To attach the holding member 18 to the receiving member 17, as shown in FIG. 7, the hanger body 18 is on the upper side and the connecting rod 21 is on the lower side. The hanger device 10 is attached to the holding member 18 by fitting each protrusion 20c into a pair of left and right fitting grooves 44 in the holding member 18 in advance.
The mounting position of the hanger device 10 with respect to the holding member 18 at this time is determined by which of the plurality of engaging portions 47 of the corrugated portion 48 is engaged with the engaging groove 45.
The relative position is changed by moving the pair of left and right support rods 20 and 20 in the vertical direction with respect to the holding member 18 while elastically deforming the rearward protrusion 46 forward.

  In this way, the holding member 18 with the hanger device 10 mounted in a desired vertical position is lowered from above the receiving member 17, and as shown in FIGS. 3 and 9, the holding member 18 faces downward. The insertion portion 38 is fitted into the receiving hole 29 in the receiving member 17, and the upward projection 34 at the rear portion of the receiving member 17 is fitted into the upward fitting recesses 42 a and 39 a in the holding member 18. The holding member 18 is placed on the protrusion 17 a of the receiving member 17.

  Next, in this state, as shown in FIG. 9, the fixing screw 52 is inserted upward from the screw insertion hole 35 that opens downward from the receiving member 17, and is screwed into the screw hole 41 of the holding member 18. And tighten.

  In the hanger device 10 attached to the backrest 9 in this manner, the concave groove 25 in the receiving member 17 is fitted into the downward protrusion 14b at the lower rear edge of the upper frame flange 14, and the upward protrusion 26 is The upper surface of the front portion 17b of the receiving member 17 is brought into contact with the lower surface of the upper frame rod 14 so as to be fitted into a pair of left and right upward concave portions 14c at the front surface of the lower surface of the upper frame rod 14, and the receiving member 17 is raised. The standing member 27 is screwed to the rear surface of the upper auxiliary frame member 14a in a state where the front surface of the portion 27 is in contact with the rear surface of the mounting portion of the upper auxiliary member 14a. In particular, the mounting strength of the receiving member 17 can be strongly supported against a downward load applied to the protrusion 17a of the receiving member 17.

  Further, in this mounted state, the bottom surface of the receiving groove 33 which is inclined forward and upward is in contact with the front surface of the rearward projection 46, and the rearward projection 46 cannot be elastically deformed forward. The plurality of engaging portions 47 of the corrugated portion 48 that engages with the engaging groove 45 cannot be changed. Therefore, the support rod 20 does not move in the vertical direction with respect to the holding member 18, and the hanger device 10 is strongly held at the height position at the time of mounting.

In order to adjust the vertical position of the hanger device 10, the fixing screw 52 is loosened, the holding member 18 is moved upward from the receiving member 17, and the front surface of the rearward protruding portion 46 is inclined to the front in the receiving groove 33. A pair of left and right support rods 20 are formed while elastically deforming the rearward projection 46 forward while forming an elastic bending allowance space forward of the rearward projection 46 therebetween. 20 is moved in the vertical direction with respect to the holding member 18, and the plurality of engaging portions 47 of the corrugated portion 48 engaged with the engaging groove 45 of the rearward protruding portion 46 are changed one by one.
After the hanger device 10 is set to a desired height, the fixing screw 52 is tightened to fix the holding member 18 to the normal position of the receiving member 17, so that the hanger device 10 moves to the holding member 18 without moving up and down. Retained.

  In addition, in a state where the holding member 18 is fixed to the regular position of the receiving member 17, an elastic bending allowable space is formed in front of the rearward projecting portion 46, so that the hanger device 10 is kept in the mounted state. The vertical position can be adjusted.

  As described above, the receiving member 17 is attached in advance to the back surface of the backrest 9, and then the holding member 18 that has previously held the hanger device 10 is attached to the protrusion 17a of the receiving member 17, or If the hanger device 10 is held by the holding member 18 after the holding member 18 is attached to the protrusion 17a, the hanger device 10 can be easily and neatly attached to the backrest 9 and work efficiency is improved. be able to.

  Furthermore, an optional member such as the hanger device 10 can be attached to the backrest 9 of any shape, and the shape of the backrest 9 is not limited for the attachment of the optional member, and The attachment position of the optional member with respect to the back surface of the flange 9 is not limited, and the optional member can be attached to any part.

  Moreover, since both the receiving member 17 and the holding member 18 are attached to the back side of the backrest 9, the receiving member 17 and the holding member 18 do not protrude forward of the backrest 9 and do not hinder the seated person.

The present invention can be implemented in the following different forms without departing from the scope thereof, for example.
(1) After attaching the receiving member 17 to the backrest 9 and attaching the holding member 18 to the receiving member 17, the hanger device 10 is attached to the holding member 18.
(2) The hanger device 10 is fixed to the holding member 18.
(3) The backrest 9 of the chair has a back frame and a back plate provided in the back frame, and the hanger device 10 is attached to the upper frame of the back frame via the receiving member 17 and the holding member 18. Install.

DESCRIPTION OF SYMBOLS 1 Caster 2 Leg rod 3 Leg 4 Leg column 5 Support base 6 Seat 7 Axis 8 Back support frame 9 Backrest 10 Hanger device (optional member)
11 Back frame
12 Upholstery member 13 Side frame rod 14 Upper frame rod 14a Upper auxiliary frame member 14b Downward protrusion 14c Upward recess 15 Lower frame rod 16 Forward piece 17 Receiving member 17a Protrusion 17b Front portion 18 Holding member 19 Hanger body 20 Support rod 20a Vertical Ridge portion 20b curved portion 20c ridge 21 connecting rod 22 stepped portion 23 cutout hole 24 rib 25 concave groove 26 upward projection 27 upright portion 27a thick portion 28 screw insertion hole 29 receiving hole 30 slit 31 rear wall 32 side wall 32a thickness Meat portion 33 Receiving groove 34 Projection portion 35 Screw insertion hole 36 Upper plate portion 37 Rear wall portion 38 Insertion portion 39 Rib 39a fitting recess 40 Boss 41 Screw hole 42 Rib 42a fitting recess 43 Thick portion 44 fitting groove 45 Fitting groove 46 Backward projecting portion 47 Engaging portion 48 Wave portion 49 Fitting groove 50 Fixing screw 51 Screw hole 52 Fixing screw

Claims (6)

An optional member mounting structure for the chair backrest,
To a backrest of a chair, characterized in that a receiving member having a protrusion projecting rearward is attached to the back surface of the backrest, and a holding member holding the option member is attached to the protrusion of the receiving member. Mounting structure for optional parts.   A receiving hole that opens upward is provided on the upper surface of the protruding portion of the receiving member, and the receiving member is held in the receiving member by fitting a downward insertion portion provided on the front lower surface of the holding member. The attachment structure of the optional member to the backrest of Claim 1 which attached the member.   The backrest according to claim 1 or 2, wherein a protrusion projecting upward is provided on an upper surface of the protrusion of the receiving member, and the protrusion is fitted in an upward fitting recess provided on the lower surface of the holding member. Mounting structure for optional parts.   The backrest of the chair according to any one of claims 1 to 3, wherein the upper surface of the front portion of the receiving member is brought into contact with the lower surface of the mounting portion constituting a part of the backrest, and the receiving member is fixed to the mounting portion. Mounting structure for optional parts.   The optional member for the backrest of a chair according to claim 4, wherein the front surface of the standing portion that stands up from the rear of the front upper surface of the receiving member is brought into contact with the rear surface of the mounting portion, and the receiving member is fixed to the mounting portion. Mounting structure.   The chair according to claim 5, wherein the standing portion of the receiving member is fixed to the rear surface of the mounting portion with a fixing screw facing in the front-rear direction, and the holding member is fixed to the protruding portion of the receiving member with a fixing screw facing in the vertical direction. Mounting structure for optional members on the backrest.

Images