JP2734787B2 - desk - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a desk suitably used in an office or the like.

[0002]

2. Description of the Related Art Conventionally, in this type of desk, generally, left and right legs are connected by a receiving bar and other horizontal bars, and a top plate is placed and fixed on the receiving bar. .

[0003] In other words, in the conventional one, a rigid main body is constituted by legs and various crosspieces, and a top plate is mounted on the main body.

[0004]

However, the conventional top plate is designed to be reinforced by the receiving bar.
Therefore, unless a large number of portions of the top plate are firmly fixed to the receiving beam, the top plate is likely to be warped or bent. Moreover, unless the left and right legs are firmly connected to each other by the support, it becomes difficult to secure the rigidity of the main body, and it becomes impossible to secure the support rigidity of the top plate.

[0005] For this reason, the conventional one requires a large number of bolts to be used for connecting the legs and connecting the top plate and the receiving beam, and there is a problem that a great deal of time and labor is required for assembly and disassembly. .

[0006] On the other hand, offices have recently become OA, and many wirings have been handled. Then
In the conventional desk described above, it is customary to hang down on the floor with the wiring on the top plate exposed, and to lay the floor on the floor. For this reason, it is unsightly, hinders traffic, and may be broken when stepped on a leg or the like.

An object of the present invention is to solve such a problem.

[0008]

In order to achieve the above object, the present invention employs the following configuration.

That is, as shown in FIG. 1, the desk according to the present invention comprises a top plate a, a leg b, a taper engaging portion c,
It has a claw-shaped engaging portion d and a back plate e. Top plate a
Has a structure in which a metal plate g is attached to both upper and lower surfaces of a frame f. The leg b has an upward surface h joined to the lower surface n of the top plate a, and the top plate a
The arm j is rigidly provided along the leading edge i. The tapered engaging portion c includes a concave tapered surface k provided at a leading edge i of the top plate a,
The leg b is provided with a convex tapered surface l provided on the arm j. By sliding the leg b toward the front m side relative to the top plate a, the concave tapered surface k and the convex tapered surface k are formed. The configuration is such that the tapered surface 1 can be in close contact with the tapered surface l. The claw-shaped engaging portion d has a bent claw o protruding from the upward surface h of the leg b,
A hook hole p recessed in the lower surface n of the top plate a, the bent claw o is inserted into the hook hole p, and the leg b slides toward the front m side with respect to the top plate a. By doing so, the bent claw o can be engaged with the hook hole p. The rear plate e is disposed closer to the distal end q than the distal end edge i of the top plate a, and forms an openable and closable wiring duct space s for accommodating the wiring t with the distal end edge i. Is configured to obtain. In a state where the engaging portions c and d are engaged, the arm j is tightly coupled to the leading edge i of the top plate a by the fastener r, and the rear plate e is mounted on the leading end q side. Features.

In this case, a convex tapered surface may be provided at the leading edge i of the top plate a, and a concave tapered surface may be provided at the arm j of the leg b. Alternatively, a bent claw may be protruded from the lower surface n of the top plate a, and a hook hole may be formed in the upper surface h of the leg b.

As a specific embodiment for making the wiring duct space openable and closable, a space between the top edge of the top plate and the upper edge of the back plate is continuous with the top surface at the closed position and at the open position. An example in which an upper lid that opens the wiring duct space upward is provided.

In order to properly store the wiring, it is desirable that a bottom wall of the wiring duct space is formed on the inner surface of the back plate and is attached.

In the case where a plurality of top plates are connected in series, it is necessary to arrange the wiring between the leading edge of the top plate and the side edge of the back plate between the top edge and the side edge of the back plate. It is preferable to provide a side lid that continuously opens the wiring duct space outward at the open position.

In order to make the legs rigid and excellent in appearance, a steel skeleton in which an upper arm forming an upward surface is connected to a supporting base material installed on the floor via a support column. And a cover made of a synthetic resin for covering the outer surface of the skeleton.
It is effective to compose with the body.

The skeleton body having a simple structure and ensuring rigidity has an upper arm portion formed by fitting an outer channel material and an inner channel material opening upward in a partially pipe-shaped manner and welding the support base material. The outer channel material and the inner channel material that are opened downward are fitted and welded in a partial pipe shape.

In this case, it is preferable that the strut penetrates the upper channel portion and the outer channel material of the support base material and is rigidly connected to the inner channel material, and the upward facing surface is the outer channel material of the upper arm portion and / or the upper channel portion. Advantageously, it is set at the upper edge of the side wall of the inner channel material. In addition, the bent claw may have its base end fixed to the bottom wall of the inner channel material of the upper arm portion and its upper end protruded above the upward surface.

As a specific embodiment of the cover body,
Front and rear covers attached to the upper arm from below
And a front cover and a rear cover mounted on the support base from above, and an intermediate cover mounted on the support from the left and right. The intermediate cover is mounted with the front cover and the rear cover mounted. It is conceivable that the cover is unevenly engaged with those covers.

[0018]

With such a construction, the upper surface of the leg is brought into contact with the lower surface of the top plate, and in this state, the leg is slid to the front end side with respect to the top plate to thereby obtain the claw. The bent claw of the engaging portion engages with the hook hole, the arm of the leg approaches the top edge of the top plate, and the convex tapered surface of the tape engaging portion becomes concave. -Abut against the surface. In this state, when the arm is tightened to the top plate with a fastener, the convex tape surface comes into close contact with the concave tape surface so that the arm is fixed to the top plate. . Since the arm is rigidly attached to the leg, if the arm is strongly connected to the top, the leg cannot tilt with respect to the top. Moreover, if the arm is fixed to the top edge of the top plate so that the legs cannot move back and forth, the bent claws will not fall out of the hook holes. There is no separation from the surface.

In addition, it forms a wiring duct space that can be opened and closed between the top edge of the top plate and the back plate. For this reason, the taper engaging portion can be blinded by the rear plate, and the wiring on the top plate can be appropriately dropped from the leading edge into the wiring duct space and stored.

[0020]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is an exploded perspective view of the desk. 3 to 12 show a desk assembled state. FIG. 3 is a front view, FIG. 4 is a plan view, FIG. 5 is a right side view, FIG.
7 is an enlarged rear cross-sectional view taken along line AA in FIG. 4, FIG. 8 is an enlarged cross-sectional view front part thereof, and FIG. 9 is an enlarged rear cross-sectional view taken along line BB in FIG. 10 is a front side partial enlarged sectional view, FIG. 11 is a top plate side partial enlarged sectional view along line CC in FIG. 4, and FIG. 12 is a leg side partial enlarged sectional view. As shown in these drawings, the desk includes a top plate 1, legs 2, a taper engaging portion 3, a claw-shaped engaging portion 4, and a back plate 5.

As shown in FIG. 13 and FIG. 14 and plan views 15 and 16 partially broken in steps along lines D ₁ , D ₂ and D _{3 in} FIGS. Frame 11
Has a flash structure in which metal steel plates 12 and 13 are attached to both upper and lower surfaces. More specifically, the frame 11 includes a pipe-shaped front-side frame 11a and a front-side frame 11b.
And the left and right side frame members 11c, and a honeycomb-shaped paper core 14 is disposed inside the honeycomb structure. Steel plates 12 and 13 are respectively attached to the upper and lower surfaces of the frame 11 and the paper core 14 via an adhesive, and these frames 11 and the steel plates 12 and 13 are pressed and bonded.
And the paper core 14. A rear edge member 15 made of hard vinyl chloride steel plate having a trapezoidal groove 15a is attached to the front end side of the front end side frame member 11a, and the surface of the rear edge member 15 is attached to the front end edge of the top plate 1. 1a. A front edge member 17 made of a hard vinyl chloride steel plate is also attached to the front side of the front side frame member 11b, and an edge member made of a soft vinyl chloride steel plate (not shown) is further provided on the surface of the front edge member 17. Is stuck. further,
The side frame member 11c has the same shape as the front side frame member 11b, and has a lateral edge member 18 made of a hard vinyl chloride steel plate adhered to the surface. Then, the steel plate 12 on the upper side of the top plate 1
A melamine decorative board 16 is stuck on the upper surface of.

The leg 2 is, as shown in FIG.
And a cover 2b. The skeleton 2a is shown in FIGS. 2 and 17 and a plan view 18 and a right side view 1 of FIG.
9. As shown in the left side view 20, each of the upper arm portions 21 in which the outer channel material 21a and the inner channel material 21b which open upward are partially welded and spot-welded.
And a support base material 22 in which the outer channel material 22a and the inner channel material 22b opening downward are fitted in a partial pipe shape and spot-welded, and the outer channel material 21a of the upper arm portion 21 and the support base material 22 , 22a and a pipe-like column 23 which rigidly connects the inner channel members 21b, 22b. Then, it has set the side wall upper edge 21b ₁ of the side wall upper edge 21a ₁ and an inner channel member 21b of the outer channel member 21a of the upper arm 21 as an upward surface. Note that the the rear side of the support 23 constituted by joining the two plate members 24 _1, 24 ₂ A, as shown in FIGS. 17 to 23 - and arm 24 is fixed to the base end portion 24a Yes,該A - has to protrude above the upper end horizontal portion 24b of the upward surface 21a _1, 21b ₁ of the arm 24. Then, the A - to the front side plate 24 ₁ in the upper horizontal portion 24b of the arm 24, forms a projection 25 which forms a cross-section trapezoidal. On the other hand, the cover body 2b is shown in FIGS.
As shown in FIG. 7, the front cover 21c and the rear cover 21d are attached to the upper arm 21 from obliquely below, and the front cover 22c and rear cover are attached to the support base 22 from obliquely above.
22d and a pair of intermediate covers 23a mounted on the support 23 from the left and right. Then, with the front covers 21c and 22c and the rear covers 21d and 22d mounted, the intermediate cover 23b is moved to the covers 21c and 21d.
The upper and lower ends of the covers 22c and 22d are engaged with the concave and convex portions.

The taper engaging portion 3 is shown in FIGS.
As shown in FIGS. 24 and 25, a concave tapered surface 31 formed on the front edge 1a of the top plate 1 and a convex tapered surface 32 provided on the arm 24 of the leg 2 are provided. Is provided. 24 is a partially enlarged sectional view taken along line EE in FIG. 4, and FIG. 25 is a sectional view taken along line FF in FIG.
That is, the concave tapered surface 31 is set on the slope of the trapezoidal groove 15a shown in FIG.
23 is set on the slope of the ridge 25 shown in FIG. Then, as shown in FIGS. 7, 9, and 11, the lower surfaces 1b of the top plate 1 are placed on the upper surfaces 21a ₁ and 22b ₁ of the legs 2 as shown in FIGS. Thus, the legs 2 are arranged at the same height position, and the legs 2 are slid toward the front side with respect to the top plate 1 from this state so that they can be brought into close contact with each other. When the taper surfaces 31 and 32 are in close contact with each other, the bolt insertion hole 24 provided on the arm 24 side is provided.
c and 24d are set so as to coincide with the screw holes 1d provided on the leading edge 1a side. Then, the bolt insertion hole 24
The bolt 6 as a fastening tool inserted through c and 24d is screwed into the screw hole 1d.

The claw-shaped engaging portion 4 is shown in FIGS.
As shown in FIGS. 26 to 28, the leg 2 has a bent claw 41 protruding from the upward surfaces 21 a ₁ and 21 b ₁ , and a hook hole 42 formed in the lower surface 1 b of the top plate 1. Do it. 26 is a partially enlarged sectional view taken along line GG in FIG. 4, and FIG. 27 is a sectional view taken along line HH in FIG.
FIG. 28 is a plan view of FIG. That is, the upper arm 21
Metal fittings 43 are fixed at two places on the bottom wall of the inner channel material 21b, and the bent claws 41 are provided in pairs at predetermined distances by bending these metal fittings 43. ing. Then, the tips are respectively upward facing surfaces 21a.
_1, is extended upward from 21b _1, are bent to the front side. The hook holes 42 are provided in pairs at two locations by punching out the lower surfaces of the left and right side frame members 11c of the top plate 1 and the steel member 13 corresponding to the bent claws 41. The horizontal distance between the hook holes 42 substantially corresponds to the horizontal distance between the bending claws 41, and the longitudinal dimension of the hook holes 42 is set slightly larger than the plane size of the bending claws 41. And FIG.
As shown by the imaginary line in FIG. 7, the upward facing surfaces 21a ₁ , 21b ₁ of the leg 2 are slightly deviated to the rear side from the normal mounting position with respect to the top plate 1 with respect to the top plate 1, and The bent claw 41 is inserted through the hook hole 42 into the inner space of the top plate 1, and the leg 2 is moved from that position to the top plate 1.
The front end of the bent claw 41 can be brought into contact with the inner surface of the side frame member 11c by sliding the front side toward the front side.

The engagement state of the claw-shaped engaging portion 4 can be obtained simultaneously when the tapered engaging portion 3 is engaged.

In this desk, however, the two engaging portions 3,
The top plate 1 is firmly joined to the leg body 2 by tightening the bolts 6 with the engagement of the back plate 4, and thereafter, the back plate 5 is disposed closer to the front end than the front edge 1 a of the top plate 1. I have to. As shown in FIG. 2 and FIG.
A decorative plate 52 made of a rigid resin in which the bracket 51 is fixed to the inner surfaces of the left and right bent pieces 52a, and upper and lower horizontal bars 53a projecting inward from the bracket 51. 53b, and a bar 57 engaged from above from between the horizontal rails 53a, 53a and between the horizontal rails 53b, 53b. The width dimension of the decorative board 52 substantially corresponds to the distance between the intermediate covers 23a of the left and right legs 2, and the vertical dimension corresponds to a size that can substantially cover the lower limb space of the top board 1.
The rear plate 5 is provided with upper and lower hook holes 54 and 55 and a bolt insertion hole 56 penetrating the bracket 51 and the decorative plate 52, and the hook holes 54 and 55 are connected to the leg 2 at the position where the rear plate 5 is provided. Engaging projections 26 and 28 projecting from
And screw the bolt 27 passing through the bolt insertion hole 56 into the screw hole 27 a provided in the leg 2, so that the rear plate 5 is fixed and the front edge 1 a of the top plate 1 is fixed. A wiring duct space S is formed therebetween. For this purpose, as shown in FIG. 19, the rear cover 21 d is attached to the rear side of the upper arm 21 of the leg 2, and the engagement protrusion 26 can be screwed through the rear cover 21 d with the rear cover 21 d attached. A nut 26a is provided, and brackets 23b and 23c are protruded from the back side of the column 23 toward the back, and after attaching the intermediate cover 23a to the brackets 23b and 23c, the intermediate cover 23a is penetrated. Nut 27 to which the bolt 27 or the engagement protrusion 28 can be screwed respectively.
a, 28a are provided.

In FIG. 2, reference numeral 71 denotes an upper cover which is continuous with the top plate surface 2c at the closed position and which opens the wiring duct space S upward at the open position.
73 is a U-shaped frame for forming a window for opening the wiring duct space S to the side of the top plate 1. Numeral 74 is a side cover for opening and closing the window of the U-shaped frame.
In FIG. 7, reference numeral 8 denotes an inner surface plate, which is supported by left and right brackets 51 and arranged in parallel with the back surface plate 5. Further, in FIG. 11, reference numeral 9a denotes a hole provided in the upper arm portion 21 of the leg body 2 so that a resin projection (not shown) projecting from the front cover 21c can be fitted and held. In FIG. 12, reference numeral 9b denotes a hole provided in the supporting base material 22 of the leg 2, so that a resin projection (not shown) projecting from the front cover 22c can be fitted and held.

With a desk having such a configuration,
The assembly and disassembly can be performed extremely simply. That is, at the time of assembling, as described above, the upward surfaces 21a ₁ and 21b ₁ of the leg 2 are attached to the lower surface 1b of the top 1 and the leg 2 is moved forward with respect to the top 1 in this state. By sliding, the bent claw 41 of the claw-shaped engaging portion 4
Is engaged with the hook hole 42 and the arm 2 of the leg 2 is
4 approaches the leading edge 1 a of the top plate 1, and the convex taper surface 32 of the taper engaging portion 3 comes into contact with the concave taper surface 31. When the arm 24 is tightened to the top plate 1 with the bolts 6 in this state, the convex taper surface 32 comes into close contact with the concave taper surface 31 so that the arm 24 comes into contact with the concave plate surface 31. Fixed to 1. Since the arm 24 is rigidly attached to the leg 2,
When the arm 24 is firmly connected to the top 1, the legs 2
Can not be tilted. Moreover, the arm 24
Is fixed to the leading edge 1a of the top plate 1 so that the leg 2 cannot move back and forth, the bent claw 41 does not come off from the hook hole 42, so that the lower surface 1b of the top plate 1 and the leg 2 The upward surfaces 21a ₁ and 21b ₁ are not separated from each other. When the above operation is performed in reverse, the connection between the top 1 and the legs 2 is released.

As described above, the desk has a structure in which the top plate 1 can exhibit rigidity by itself, and the tape engaging portion 3 is attached to the top plate 1 as a structural base. And the leg 2 can be attached via the claw-shaped engaging portion 4 so that the leg 2 cannot be tilted and moved back and forth. There is no need to increase the stiffness by using. For this reason, the illustrated desk can be used as an epoch-making desk with extremely reduced rattling, with significantly reduced man-hours for assembling and disassembling as compared with the conventional desk.

In addition, the desk is provided with a top edge 1 of the top plate 1.
a wiring duct space S is formed between the back cover 5 and the base plate 5 along the grove 57.
1 to open the ceiling plate 1 from an appropriate position. For this reason, the taper engaging portion 3 can be hidden by the rear plate 5, and the wiring on the top plate 1 is dropped into the wiring duct space S from an appropriate position through the distal end side of the distal edge 1a and stored. This makes it possible to eliminate the conventional inconvenience when using OA equipment or the like. In addition, in this embodiment, the wiring duct space S can be opened to the side via the left and right lateral lids 74. For this reason, when the top plate 1 is continuously provided on the left and right, the wiring duct space S is continuously formed, and the wiring can be routed more efficiently. Further, in this device, the leg 2 is constituted by a skeleton 2a and a cover 2b, and the skeleton 2a is formed by channel members 21a, 21b, 22a, 22b and a support 23. For this reason, the leg 2 can be used without any special processing.
Can be easily finished to a required shape, and sufficient rigidity can be ensured even by performing spot welding. Further, since the surface is covered with the cover body 2b made of a rigid resin, it is easy to finish the appearance and it does not involve a cold touch like a metal.

The configuration of each section is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

[0033]

As described above, the desk according to the present invention has a structure in which the top plate is capable of exhibiting rigidity by itself, thereby eliminating the need for reinforcement by a receiving beam, and providing the top plate having such rigidity with a structural base. The leg is attached to this top plate via a taper engaging portion and a claw-shaped engaging portion so as not to tilt or move back and forth. In this state, the leg is attached to the top edge of the top plate with a fastening tool. Since it is configured only by tightening and tightening, the number of manufacturing and assembling man-hours is drastically reduced compared to the conventional one, the number of parts is small, the production cost is low, and there are various excellent features such as extremely little backlash. With the effect. In addition, in the desk of the present invention, a back plate is disposed further to the front edge of the top edge of the top plate, and a wiring duct space that can be opened and closed is formed between the back plate and the top edge of the top plate. For this reason, the taper engaging portion can be hidden by the back plate, and the wiring on the top plate can be appropriately dropped and stored in the wiring duct space from the leading edge, so that the OA equipment can be used. Usability can be effectively improved.

[Brief description of the drawings]

FIG. 1 is a configuration explanatory diagram of the present invention.

FIG. 2 is an exploded perspective view showing one embodiment of the present invention.

FIG. 3 is a front view of the assembled state of the embodiment.

FIG. 4 is a plan view of the same.

FIG. 5 is a right side view of the same.

FIG. 6 is a rear view of the same.

FIG. 7 is a partially enlarged cross-sectional view on the back side along the line AA in FIG. 4;

FIG. 8 is a partially enlarged sectional view of the front side.

9 is a partially enlarged cross-sectional view on the back side along the line BB in FIG. 4;

FIG. 10 is a partially enlarged sectional view of the front side.

FIG. 11 is a partial enlarged cross-sectional view taken along the line CC in FIG. 4;

FIG. 12 is an enlarged sectional view of the same leg side.

FIG. 13 is a cross-sectional view showing the vicinity of the leading edge of the top plate in the embodiment.

FIG. 14 is a sectional view of the vicinity of the front surface of the top plate in the embodiment.

FIG. 15 is a partially broken plan view showing the vicinity of the top end side of the top plate in the embodiment.

FIG. 16 is a partially broken plan view of the vicinity of the front surface of the top plate in the embodiment.

FIG. 17 is a diagram of the skeletal body in the same example as viewed from the outside surface side.

18 is a plan view of FIG.

FIG. 19 is a right side view of the same.

FIG. 20 is a left side view of the same.

FIG. 21 is a front view of the arm in the embodiment.

FIG. 22 is a plan view of FIG. 21;

FIG. 23 is a right side view of the same.

FIG. 24 is a partially enlarged cross-sectional view along the line EE in FIG. 4;

FIG. 25 is a sectional view taken along line FF in FIG. 24;

FIG. 26 is a partially enlarged cross-sectional view along the line GG in FIG. 4;

FIG. 27 is a sectional view taken along line HH in FIG. 26;

FIG. 28 is a plan view of FIG. 27;

[Description of Signs] 1 ... Top plate 1a ... Front edge 1b ... Bottom surface 2 ... Leg 2a ... Skeleton 2b ... Cover body 3 ... Taper engaging portion 4 ... Claw-shaped engaging portion 5 ... Back plate 6 ... fastening members (bolts) 11,11a, 11b, 11c ... frame 12, 13 ... metal plate 21a _1, 21b ₁ ... upward surface 21 ... upper arm 22 ... supporting substrate 21a, 22a ... outer channel member 21b, 22b ... Inner channel material 21c, 22c ... front cover 21d, 22d ... rear cover 23 ... pillar 23a ... intermediate cover 24 ... arm 31 ... concave taper surface 32 ... convex taper surface 41 ... bending Claw 42 ... Hook hole 57 ... Toy 71 ... Top cover 74 ... Side cover S ... Wiring duct space

Claims (10)

(57) [Claims] 1. A desk comprising a top plate, a leg, a tapered engagement portion, a claw-shaped engagement portion, and a back plate, wherein the top plate has metal on both upper and lower surfaces of the frame. plate and without was formed by structure additionally provided a leg Tsuyoshi設, together includes an upward surface to be bonded to the lower surface of the top plate, an arm along the leading edge of the top plate to the upper end The tapered engagement portion includes a concave tapered surface provided on one of the distal end edge of the top plate and the arm of the leg, and a convex tapered surface provided on the other, By sliding the leg body to the front side with respect to the top plate, the concave tapered surface and the convex tapered surface can be brought into close contact with each other. A bent claw protruding from one of the upward surfaces of the leg, and a hook hole recessed in the other are provided. The bent claw can be engaged with the hook hole by inserting the leg into the hook hole and sliding the leg toward the front side with respect to the top plate. And a wiring duct space that can be opened and closed with the leading edge, and the arm is stopped in a state where each engaging portion is engaged. A desk characterized in that it is tightly connected to the top edge of the top plate with a fitting, and a back plate is attached to the top side. 2. An upper lid is provided between a top edge of a top plate and an upper edge of a back plate to be continuous with the top plate surface at a closed position and open upward a wiring duct space at an open position. The desk according to claim 1, wherein 3. A fin is formed on the inner surface of the back plate to form a bottom wall of the wiring duct space.
Desk described. 4. A side cover is provided between the top edge of the top plate and the side edge of the back plate to be continuous with the outer surface of the leg at the closed position and open the wiring duct space outward at the open position. The desk according to claim 1, wherein 5. A skeleton body made of a steel material in which a leg is connected to an upper arm portion forming an upward surface via a support to a supporting base material arranged on a floor, and a synthetic body covering the outer surface of the skeleton body. 2. The desk according to claim 1, wherein the desk comprises a resin cover. 6. The upper arm portion is formed by fitting and welding an outer channel material and an inner channel material opening upward in a partial pipe shape, and the supporting base material has an outer channel material and an inner channel material opening downward. The desk according to claim 5, characterized in that is fitted and welded into a partial pipe shape. 7. The desk according to claim 6, wherein the column is rigidly connected to the inner channel material through the upper arm portion and the outer channel material of the support base material. 8. The upper channel has an outer channel material of an upper arm and / or
7. The desk according to claim 6, wherein the desk is set at an upper edge of a side wall of the inner channel material. 9. The desk according to claim 8, wherein the bending claw has a base end fixed to the bottom wall of the inner channel material of the upper arm portion and an upper end protruding above the upward surface. . 10. A front cover and a rear cover mounted on the upper arm from below, a front cover and a rear cover mounted on the support base from above, and an intermediate cover mounted on the support from right and left. 2. The desk according to claim 1, wherein the intermediate cover is unevenly engaged with the front cover and the rear cover while the front cover and the rear cover are mounted.