US20080149006A1

US20080149006A1 - Folding Desk

Info

Publication number: US20080149006A1
Application number: US11/883,824
Authority: US
Inventors: Luhao Leng
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-05-19
Filing date: 2004-09-22
Publication date: 2008-06-26
Also published as: WO2005110151A1; CN2710438Y

Abstract

A folding desk made of plastic composite plates includes a desk face plate, a left side plate, a right side plate and a front baffle. The left side plate and the right side plate are linkable rotationally to a left side and a right side of the desk face plate respectively. The front baffle is linkable rotationally to a lower side of the desk face plate. Position restricting and locking mechanisms are located at connecting positions between the left side of the front baffle and the left side plate or/and between the right side of the front baffle and the right side plate, and position restricting and locking mechanisms stabilize the desk when open. The desk face plate, the left side plate, the right side plate and the front baffle are at least partially plastic composite plates.

Description

TECHNICAL FIELD

The present invention relates to a desk, especially to a folding desk made by plastic composite boards.

BACKGROUND ART

In modern times, desk is widely used in office and home on account of its practicability. Folding desk is even more widely used because of its virtues such as occupying small space, having a small size, being convenient for storage and being convenient for transportation. Chinese patent number 96219977.X discloses a folding council board at 6 May 1998, as shown in FIG. 16, comprising a face plate 1, a shelf 2, two side plates 3 and a back plate 4. Two side plates 3 rotationally link to the left side and the right side of the face plate 1; the back plate 4 rotationally links to the underside of the face plate 1; the shelf 2 slideably links to the two side plates 3 and the back plate 4. There are fasteners between the two side plates 3 and the back plate 4, the fastener is an eccentric piece. When in folding the council board, it needs five steps: 1, turn the council board; 2, slide the shelf 2 to make it against to the underside of the face plate 1; 3, loose fasteners; 4, fold the back plate 4; 5, fold two side plates 3. The present technical proposal can come true the fold of the council board but has disadvantages as follows: firstly, the shelf 2 slideably links to the two side plates 3 and back plate 4, just because of that there is no space between the back plate 4 and the face plate 1, the council board is folded difficultly or can not be folded; secondly, the face plate 1 and the shelf 2 and two side plates 3 and the back plate 4 are all made by wood, which will waste much wood, destroy entironment; the fasteners or connecting pieces of the face plate 1 and the shelf 2 and two side plates 3 and the back plate 4 link to wood block, fasteners or connecting pieces are easily broken off, which will destroy the connection intensity of the face plate 1 and the shelf 2 and the side plates 3 and the back plate 4; thirdly, the shelf 2 slideably links to the two side plates 3 and back plate 4, if the shelf 2 is locked between two side plates 3 and the back plate 4, then the back plate 4 can not be folded at the face plate 1, then the council board can not be folded; fourthly, after folding, the thickness of the council board is the sum of the thickness of the face plate 1, the shelf 2, the side plates 3, the back plate 4, the thickness is big and will occupy a big space; fifth, the fastener is an eccentric piece, which has a bad fastness and is easy destroyed.

CONTENTS OF THE INVENTION

The purpose of the present invention is to provide a folding desk, which has a light weight, has a high strength, is easy to fold, occupies small space when it is folded.
The present invention adopts technical proposal as follows: a folding desk, comprising a desk face plate, a left side plate, a right side plate and a front baffle; the left side plate and the right side plate may link rotationally to the left side and the right side of the desk face plate respectively; the front baffle may link rotationally to the lower side of the desk face plate; there are position restricting and locking mechanisms at the connecting positions between the left side of the front baffle and the left side plate or/and between the right side of the front baffle and the right side plate, and the position restricting and locking mechanisms can make the desk stabilize at an open state; the desk face plate is plastic composite board of inhale molding, comprising a faceplate, a soleplate, a perforated plate and a liner; the perforated plate is filled between the faceplate and the soleplate, and the liner is sandwiched between the faceplate and the soleplate; the liner covers the perforated plate entirely or interval partly along the periphery of the perforated plate; the left side plate and the right side plate link to the desk face plate by hinge units, one parts of the hinge units are fixed to the liner of the desk face plate and another parts of the hinge units are fixed to the connective side plates.
The lower side of the desk face plate has a groove for accepting the front baffle; the position of the groove corresponds with the position of the folded front baffle; the length and width and depth of the groove is separately bigger than or equals to the length and width and depth of the front baffle.
The liner of the desk face plate has the shape of
; the liner and the soleplate of the desk face plate forms two grooves, thereinto one groove is for accepting the front baffle, the length and width and depth of the groove is separately slightly bigger than or equals to the length and width and depth of the front baffle.
The left side plate and the right plate and the front baffle are all plastic composite boards, comprising a faceplate, a soleplate and a liner; the liner is embedded into the plastic composite board, and the plastic composite board is also filled with paper honeycomb core or plastic honeycomb core or epispastic stuffing.
The desk face plate links to the front baffle by not less than two hinge units, one parts of the hinge units are fixed to the liner of the desk face plate and another parts of the hinge units are fixed to the connective front baffle.
The hinge unit comprises a first hinge plate, a second hinge plate and a pin; the pin drills through the first hinge plate and the second hinge plate to form a rotational hinge unit; the first hinge plate is fixed to liners of side plates or the front baffle and the second hinge plate is fixed to the liner of the desk face plate.
The first hinge plate or the second hinge plate of the plastic composite board is fixed to the liner of the plastic composite board by sealing, rivet linking or screw thread linking.
Both the first hinge plate and the second hinge plate are plastic ρ-shaped hinge or ρ-shaped hinge of sheet metal pieces or ρ-shaped hinge of sheet pieces.
The position restricting and locking mechanisms are constituted of matched L-shaped hook and C-shaped groove; the L-shaped hook has locking segment, the cross section of the locking segment has a first diameter and a second diameter, the first diameter and the second diameter have different diameters; the opening width of the C-shaped groove is smaller than the interior diameter of the C-shaped groove; the first diameter is bigger than the opening width of the C-shaped groove but is smaller than the interior diameter of the C-shaped groove; the second diameter is smaller than the opening width of the C-shaped groove; the L-shaped hook rotationally links to the liner of the front baffle, the C-shaped groove fixedly links to the liners of the left side plate or the right side plate.
The cross section of the locking segment of the L-shaped hook is oblate or rectangle or tympaniform.
The C-shaped groove is fixed to the liners of the left side plate or the right side plate by sealing, rivet linking or screw thread linking.
The C-shaped groove is plastic C-shaped groove or C-shaped groove of sheet metal pieces or C-shaped groove of sheet pieces.
The position restricting and locking mechanisms comprise matched elasticity C-shaped groove and bayoner lock; the diameter of the bayoner lock is bigger than the opening width of the elasticity C-shaped groove but is smaller than or is equal to the interior diameter of the C-shaped groove; the bayoner lock and elasticity C-shaped groove are separately fixed to the liner of the front baffle and the liner of the left side plate or the right side plate.
The position restricting and locking mechanisms comprise matched locking bolt and set nut, the locking bolt rotationally link to the liner of the front baffle, the set nut is fixed to the liners of the left side plate or the right side plate.
The front baffle and the left side plate and the right side plate are all vertical to desk face plate, and the front baffle is vertical to the left side plate and the right side plate.
The surfaces of the faceplate and the soleplate of the plastic composite board are printed with printing layer of grain of wood or marbling or complexed with film layer of grain of wood or marbling.
Comparing with the background of the technology, the present invention has virtues as follows:
firstly, the desk face plate and the left side plate and the right side plate and the front baffle are all or partly plastic composite boards, which have high strength and light weight; the position restricting and locking mechanisms can make desk stabilize at an open state, it is safe in using; it is easy to fold and occupies small space when it is folded; liners can expediently link to connecting pieces or position restricting and locking mechanisms; when fold is needed, the steps are as follows: 1, unbar position restricting and locking mechanisms; 2, fold the front baffle to make it lean against the underside of the desk face plate; 3, fold the left side plate and the right side plate to make it lean against the front baffle;
secondly, the underside of the desk face plate has groove, the front baffle are entirely folded into the groove, the thickness of the whole desk equals to the sum of the thickness of left side plate or the right side plate and the thickness of the desk face plate, which has small thickness, occupies small space, is easy for storage and transportation;
thirdly, the groove of the underside of the desk face plate is made by inhale molding, which is easy to machining, has a low factory cost and has a high strength;
fourthly, liner is embedded into plastic composite board, and the plastic composite board is also filled with paper honeycomb core or plastic honeycomb core or epispastic stuffing, which has a light weight and a high strength and a good showing;
fifthly, the desk face plate links to the front baffle by at least two hinge units, which has a high connection intensity and a long useful life, turns stably; and the hinge unit has a simple configuration;
sixthly, pin drills through the first hinge plate and the second hinge plate to form a rotational hinge unit, which has a simple configuration and turns expediently; the first hinge plate and the second hinge plate are respectively fixed to the liner of the plastic composite board, which is easy to connect;
seventhly, the first hinge plate and the second hinge plate are plastic ρ-shaped hinge, which has a low factory cost and a simple making and a high strength; the first hinge plate and the second hinge plate are ρ-shaped hinge of sheet metal pieces, which has a simple making and a high strength; the first hinge plate and the second hinge plate are ρ-shaped hinge of sheet pieces, which has a simple making and a high strength;
eighthly, the position restricting and locking mechanisms comprise matched L-shaped hook and C-shaped groove, when opening up or folding the folding desk of the present invention, rotating L-shaped hook to make the second diameter against to the C-shaped groove, so the locking segment of the L-shaped hook plugs into or gets off the C-shaped groove, namely the position restricting and locking mechanisms are at a looseness state; when the locking segment of the L-shaped hook plugs into the C-shaped groove, rotating L-shaped hook to make the first diameter against to the C-shaped groove, the locking segment of the L-shaped hook can not get off the C-shaped groove, namely the position restricting and locking mechanisms are at a locking state; the position restricting and locking mechanisms link to the liner, which connects expediently and hard, is convenient to use and has a good locking effect;
ninthly, the cross section of the locking segment of the L-shaped hook is oblate or rectangle or tympaniform, which has a simple configuration and a good locking effect.
tenthly, the position restricting and locking mechanisms comprise matched elasticity C-shaped groove and bayoner lock, when opening up or folding the folding desk, the bayoner lock can expediently plug into or get off the elasticity C-shaped groove by outside force, it is locked when the bayoner lock plugs into the C-shaped groove and it is open when the bayoner lock gets off the C-shaped groove, which is convenient to use and has a good locking effect;
eleventhly, the position restricting and locking mechanisms comprises matched locking bolt and set nut, it is locked when the locking bolt turns into the set nut and it is open when the locking bolt turns off the set nut, which is convenient to use and has a good locking effect;
twelfthly, the front baffle and the left side plate and the right side plate are all vertical to desk face plate, and the front baffle is vertical to the left side plate and the right side plate, which has a high stability;
thirteenthly, the surfaces of the faceplate and soleplate of the invention are printed with printing layer or complexed with film layer, which has a good showing and is made expediently.

BRIEF INSTRUCTIONS OF ATTACHED DRAWINGS

FIG. 1 is the sketch map of three dimensional structure of the spread state of the desk of the present invention;

FIG. 2 is the sketch map of three dimensional structure in the process of folding the desk of the present invention;

FIG. 3 is the sketch map of three dimensional structure of the folding state of the desk of the present invention;

FIG. 4 is the sketch map of local section of the first plastic composite board of the desk face plate of the present invention;

FIG. 5 is the sketch map of enlarged view of local section of the first plastic composite board of the desk face plate of the present invention;

FIG. 6 is the sketch map of bottom view of the second plastic composite board of the present invention;

FIG. 7 is the sketch map of enlarged view of local section of the second plastic composite board of the desk face plate of the present invention;

FIG. 8 is the sketch map of three dimensional structure of the first hinge unit;

FIG. 9 is the sketch map of three-dimensional explosion diagram of the first hinge unit;

FIG. 10 is the sketch map of three-dimensional explosion diagram of the second hinge unit;

FIG. 11 is the sketch map of three dimensional structure of the position restricting and locking mechanisms being at open mode.

FIG. 12 is the sketch map of three dimensional structure of the position restricting and locking mechanisms being at locking mode;

FIG. 13 is the sketch map of three dimensional structure of the L-shaped hook;

FIG. 14 is the sketch map of three dimensional structure of the C-shaped groove;

FIG. 15 is the sketch map of three dimensional structure of the U-shaped connecting piece;

FIG. 16 is the sketch map of three dimensional structure of the known desk.

EMBODIMENT

Referring to FIGS. 1 to 15, we will explain the present invention as follows.
A folding desk, as shown in FIGS. 1 to 3, comprising desk face plate 10, a left side plate 12, a right side plate 14 and a front baffle 16. The front baffle 16 and the left side plate 12 and the right side 14 plate are all vertical to desk face plate 10, and the front baffle 16 is vertical to the left side plate 12 and the right side plate 14.
The left side plate 12 and the right side plate 14 link rotationally to the left side and the right side of the desk face plate 10 respectively; the front baffle 16 link rotationally to the rear end of the lower side of the desk face plate 10; there are position restricting and locking mechanisms 18 at the connecting positions between the left side of the front baffle 16 and the left side plate 12 and between the right side of the front baffle 16 and the right side plate 14.
As shown in FIGS. 4 and 5, the desk face plate 10 is first plastic composite board, comprising a first faceplate 20 and a first soleplate 22 and a first perforated plate 24 and a first liner 26, the first perforated plate 24 is filled between the first faceplate 20 and the soleplate 22. The first faceplate 20 and the first soleplate 22 are plastic combined boards of inhale molding, the thickness of the plastic combined board varies from 0.3 to 4 mm. The edge of the first soleplate 22 extends downwards to form first lower wrapping edge 221, the lower side of the first lower wrapping edge 221 extends breadthwise forth to form a second lower wrapping edge 222, the outer side of the second lower wrapping edge 222 extend upwards to form the third lower wrapping edge 223, the third lower wrapping edge 223 has a sidestep 224. The edge of the first faceplate 20 extends downwards to form an upper wrapping edge 201. The inner side of the upper wrapping edge 201 fixedly joints to the outer edge of the first perforated plate 24 and the outer edge of the part of the third lower wrapping edge 223 above the sidestep 224. The upper wrapping edge 201 of the first plastic composite board and the lower part of the third lower wrapping edge 223 are aligned. The intermediate back part of the first soleplate 22 caves downwards to form a concave slot; the first lower wrapping edge 221 and the second lower wrapping edge 222 and the third lower wrapping 223 cooperate to form a position groove. The first liner 26 is a
shaped frame, whose section structure cooperates with the concave slot and the position groove; the first liner 26 fixedly locates in the concave slot and the position groove.
The first soleplate 22 and the first liner 26 directly form two grooves. Thereinto previous groove 28 correspond with the position of the folded front baffle 16; the length and the width and the depth of the groove 28 separately slightly bigger than the length and the width and the depth of the front baffle 16. When folded, the front baffle 16 is entirely folded into the groove 28.
The surfaces of the first faceplate 20 and the first soleplate 22 of the plastic composite board are printed with printing layer of grain of wood or marbling.
As shown in FIGS. 6 and 7, the left side plate 12 and the right side plate 14 and the front baffle 16 are all second plastic composite boards; every second plastic composite board comprises a second faceplate 30, a second soleplate 32, a second perforated plate 34 and a second liner 36; the second perforated plate 34 is filled between the second faceplate 30 and the second soleplate 32; the second liner 36 is sandwiched between the second faceplate 30 and the second soleplate 32, and the second liner 36 covers the second perforated plate 34 entirely along the periphery of the perforated plate 34. The second faceplate 30 and the second soleplate 32 are monolayer or multi-layer plastic boards, which is made by inhale molding and whose thickness varies from 0.3 to 4 mm. The edge of the second faceplate 30 extend downwards to form second upper wrapping edge 301; the edge of the second soleplate 32 extend upwards to form fourth lower wrapping edge 321; the inner circumference of the second upper wrapping edge 301 conglutinates to the outer circumference of the fourth lower wrapping edge 321, namely the superposition side of the second faceplate 30 and the second soleplate 32 is situated at the side face of every second plastic composite board.
The surfaces of the second faceplate 30 and the second soleplate 32 of the second plastic composite board are printed with printing layer of grain of wood or marbling.
As shown in FIGS. 8 and 9, the desk face plate 10 connects with the front baffle 16 by two first hinge units 52. The first hinge unit 52 comprises a first hinge plate 38, a second hinge plate 40 and a pin 42, the pin 42 drills through the first hinge plate 38 and the second hinge plate 40 to form a rotational hinge unit. The first hinge plate 38 comprises a first connecting plate 44 and three alternate first ρ-shaped hinges 46; the three alternate first ρ-shaped hinges are formed by the side face of the first hinge plate 38 extending ahead. The second hinge plate 40 comprises a second connecting plate 48 and two alternate second ρ-shaped hinges 50, the two alternate second ρ-shaped hinges 50 are formed by the side face of the second hinge plate 40 extending ahead. Two alternate second ρ-shaped hinges 50 and three alternate first ρ-shaped hinges 46 are interlaced. The first connecting plates 44 of the two first hinge plates 38 are fixed to the second liner 36 of the second plastic composite board of the front baffle 16 by screw thread. The second connecting plates 48 of the two second hinge plates 40 are fixed to the middle rail of
shaped frame of the first liner 26 of the first plastic composite board of the desk face plate 10. The front baffle 16 links rotationally to the back of the lower side of the desk face plate 10 by the two first hinge units 52.
As shown in FIG. 10, the left nether surface of the desk face plate 10 link to the left side plate 12 by two second hinge units 54. The second hinge unit 54 comprises a third hinge plate 56, a fourth hinge plate 58 and a second pin 92, the second pin 92 drills through the third hinge plate 56 and the fourth hinge plate 58 to form a rotational hinge unit. The third hinge plate 56 comprises a third connecting plate 60 and three alternate ρ-shaped third hinges 62, the three alternate ρ-shaped third hinges 62 are formed by the side face of the third hinge plate 60 extending ahead. The fourth hinge plate 58 comprises a fourth connecting plate 64 and two alternate ρ-shaped fourth hinges 66, the two alternate ρ-shaped fourth hinges 66 are formed by the side face of the fourth hinge plate 64 extending ahead. Two alternate ρ-shaped fourth hinges 66 and three alternate ρ-shaped third hinges 62 are interlaced. The second pin 92 drills through the circular hole of the three alternate ρ-shaped third hinges 62 and the circular hole of the two alternate ρ-shaped fourth hinges 66. The third connecting plates 60 of the two third hinge plates 56 are fixed to the second liner 36 of the second plastic composite board of the left side plate 12 by screw thread. The fourth connecting plates 64 of the two fourth hinge plates 58 are fixed to one rail of the left side of the first liner 26 of the first plastic composite board of the desk face plate 10 by screw thread. The left side plate 12 links rotationally to the lower side of the left side of the desk face plate 10 by the two second hinge units 54.
The lower side of the right side of the desk face plate 10 links to the right side plate 14 by another two second hinge units 54, whose connection mode is as above. The right side plate 14 links rotationally to the lower side of the right side of the desk face plate 10 by the two second hinge units 54.
As shown in FIGS. 11 to 15, the left side of the front baffle 16 links to the left side plate 12 by position restricting and locking mechanisms 18, which can make the desk keep its stabilization of unfolding. The position restricting and locking mechanisms 18 comprise matched L-shaped hook 68, C-shaped groove 70 and U-shaped connection piece 72.
Two ends of the L-shaped hook separately form orientation locking piece 74 and rotational handhold piece 76; the main body of the L-shaped groove 68 has rotational connection part 78 and locking segment 80. The cross section of the locking segment 80 is oblate, and the locking segment 80 has a first diameter and a second diameter, the first diameter is bigger than the second diameter.
C-shaped groove 70 has hook-shaped opening 82 and a fifth connection piece 84, the width of the opening 82 is smaller than the diameter of the inner circular hole 90 of the groove 70. The first diameter is bigger than the width of the opening 82 of the C-shaped groove 70 but is smaller than the diameter of the inner circular hole 90 of the groove 70; the second diameter is smaller than the width of the opening 82 of the C-shaped groove 70. The fifth connection piece 84 of the C-shaped groove 70 is fixed to the second liner 36 of the second plastic composite board of the front baffle 16 by screw thread.
U-shaped connection piece 72 has sixth connection plate 86 and two rotational connection slices 88, the two rotational connection slices 88 are formed by two sides of the sixth connection plate 86 separately extending breadthwise. The rotational connection part 78 of the L-shaped hook 68 links rotationally to two rotational connection slices 88. Orientation locking piece 74 of the L-shaped hook 68 locates in the side of the rotational connection slices 88 to restrict its longitudinal slippage. The sixth connection plate 86 of the U-shaped connection piece 72 is fixed to the second liner 36 of the second plastic composite board of the left side plate 12 by screw thread.
The right side of the front baffle 16 links to the right side plate 12 by another position restricting and locking mechanisms 18, which can make the desk keep its stabilization of unfolding, which has same structure with the position restricting and locking mechanisms 18 above.
While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is understood that present invention is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.

INDUSTRY PRACTICABILITY

The present invention is a folding desk made by plastic composite board, which has a light weight, a high strength, a good showing, and is convenient for transportation, and has a simple production process, and can be industrialized, has a good industry practicability.

Claims

1. A folding desk, comprising: a desk face plate, a left side plate, a right side plate and a front baffle; the left side plate and the right side plate being linkable rotationally to the left side and the right side of the desk face plate respectively; the front baffle being linkable rotationally to the lower side of the desk face plate; position restricting and locking mechanisms being disposed at the connecting positions between the left side of the front baffle and the left side plate or/and between the right side of the front baffle and the right side plate, and the position restricting and locking mechanisms stabilize the desk upon opening; the desk face plate is plastic composite board of vacuum molding, comprising a faceplate, a soleplate, a perforated plate and a liner; the perforated plate is sandwiched between the faceplate and the soleplate, and the liner is sandwiched between the faceplate and the soleplate; the liner at least partially covers the perforated plate along the periphery of the perforated plate; the left side plate and the right side plate link to the desk face plate by hinge units, at least one first part of the hinge units is fixed to the liner of the desk face plate and at least one second part of the hinge units is fixed to the connective side plates.

2. A folding desk according to claim 1, wherein the lower side of the desk face plate has a groove for accepting the front baffle; the position of the groove corresponds with the position of the folded front baffle; the length and width and depth of the groove is separately larger than or equals the length and width and depth of the front baffle.

3. A folding desk according to claim 1, wherein the liner of the desk face plate is a

shaped frame; the liner and the soleplate of the desk face plate forms two grooves, thereinto one groove is for accepting the front baffle, the length and width and depth of the groove is separately slightly bigger than or equals to the length and width and depth of the front baffle.

4. A folding desk according to claim 1, wherein the left side plate and the right plate and the front baffle are all plastic composite boards, including a faceplate, a soleplate and a liner; the liner is embedded into the plastic composite board, and the plastic composite board is also filled with paper honeycomb core or plastic honeycomb core or epispastic stuffing.

5. A folding desk according to claim 1, wherein the desk face plate links to the front baffle by not less than two hinge units, one part of each hinge unit is fixed to the liner of the desk face plate and another part of each hinge unit is fixed to the connective front baffle.

6. A folding desk according to claim 5, wherein the hinge unit includes a first hinge plate, a second hinge plate and a pin; the pin extends through the first hinge plate and the second hinge plate to form a rotational hinge unit; the first hinge plate is fixed to liners of the side plates or the front baffle, and the second hinge plate is fixed to the liner of the desk face plate.

7. A folding desk according to claim 6, wherein both the first hinge plate and the second hinge plate are plastic ρ-shaped hinge or a ρ-shaped hinge of sheet metal pieces or a ρ-shaped hinge of sheet pieces.

8. A folding desk according to claim 1, wherein the position restricting and locking mechanisms are constituted of a matched L-shaped hook and a C-shaped groove; the L-shaped hook has a locking segment, the cross section of the locking segment has a first diameter and a second diameter, the first diameter and the second diameter have different diameters; an opening width of the C-shaped groove is smaller than an interior diameter of the C-shaped groove; the first diameter is bigger than an opening width of the C-shaped groove but is smaller than an interior diameter of the C-shaped groove; the second diameter is smaller than the opening width of the C-shaped groove; the L-shaped hook rotationally links to the liner of the front baffle, the C-shaped groove fixedly links to the liners of the left side plate or the right side plate.

9. A folding desk according to claim 8, wherein a cross section of the locking segment of the L-shaped hook is oblate or rectangle or tympaniform.

10. A folding desk according to claim 8, wherein the C-shaped groove is fixed to the liners of the left side plate or the right side plate by sealing, rivet linking or screw thread linking.

11. A folding desk according to claim 8, wherein the C-shaped groove is made of plastic sheet metal pieces or is a C-shaped groove hinge of sheet pieces.

12. A folding desk according to claim 1, wherein the position restricting and locking mechanisms include a matched elasticity C-shaped groove and a bayonet lock; the diameter of the bayonet lock is larger than the opening width of the elasticity C-shaped groove but is smaller than or is equal to the interior diameter of the C-shaped groove; the bayonet lock and the elasticity C-shaped groove are separately fixed to the liner of the front baffle and the liners of the left side plate or the right side plate.

13. A folding desk according to claim 1, wherein the position restricting and locking mechanisms are matched locking bolt and set nut, the locking bolt rotationally links to the liner of the front baffle, the set nut is fixed to the liners of the left side plate or the right side plate.

14. A folding desk according to claim 1 wherein surfaces of the faceplate and the soleplate of the plastic composite board are printed with a printing layer of wood grain, marbling or complexed with a film layer of wood grain or marbling.