A desk convenient for primary and secondary school students to take a nap

Abstract

The present invention relates to a desk that is convenient for taking a nap, and in particular to a desk that is convenient for taking a nap for primary and secondary school students. The present invention provides a desk that allows students to lie flat for a nap and is convenient for taking a nap for primary and secondary school students. A desk that is convenient for taking a nap for primary and secondary school students includes a support, a sliding frame, a placement box, a fixed plate, an expansion mechanism and a support mechanism; the two supports are both slidably provided with sliding frames, a placement box is connected between the two sliding frames, a fixed plate is connected between the upper sides of the two sliding frames, the placement box is located on the lower side of the fixed plate, an expansion mechanism is provided on the fixed plate, and a support mechanism is connected between the expansion mechanism and the fixed plate. The present invention allows people to manually move the handle backwards, thereby causing the guide block and the expansion plate to move backwards. When the fixed plate jams the guide block, people stop moving the handle, and then people lie flat on the expansion plate and the fixed plate for a nap, thereby achieving the effect of lying flat for a nap.

Description

Technical Field

[0001] The invention relates to a desk convenient for taking a nap, in particular to a desk convenient for primary and secondary school students to take a nap. Background Art

[0002] Naps are essential for primary and secondary school students. Currently, most students sleep on their desks during naps in the classroom. This way of napping can easily cause deformation of students' cervical vertebrae over time. Therefore, it is necessary to design a desk that is convenient for naps.

[0003] Patent application: CN211533264U, published on September 22, 2020, discloses a foldable nap desk, which includes a desk cabinet, a high column, a low column and a dual-purpose pallet. The two ends of the desktop of the desk cabinet are respectively hinged to the high column and the dual-purpose pallet; when used for class, the free end of the dual-purpose pallet is supported on the top of the low column, and the desktop is in a horizontal position. When used for a nap, the desktop and the dual-purpose pallet are adjusted to an obtuse dihedral angle, and the desktop is adjusted to an inclined position to support the waist and back of the lying person. The chair is moved to the side of the free end of the dual-purpose pallet to support the lower limbs of the napper. The desk allows students to lie on the inclined desktop for a nap. This way of taking a nap can easily cause the students' cervical vertebrae to deform.

[0004] We have designed a desk that allows students to lie flat for a nap, which is convenient for primary and secondary school students to take a nap, so as to overcome the problem that existing desks that are convenient for naps easily cause students' cervical vertebrae to deform. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a desk which allows students to lie flat for a nap and is convenient for primary and secondary school students to take a nap, so as to overcome the disadvantage that the existing desks convenient for taking naps easily cause students' cervical vertebrae to deform.

[0006] To achieve the above objectives, the present invention is implemented through the following scheme: a desk that is convenient for primary and secondary school students to take naps, including a support, a sliding frame, a placement box, a fixed plate, an expansion mechanism and a supporting mechanism, two supports are slidably provided with sliding frames, a placement box is connected between the two sliding frames, a fixed plate is connected between the upper sides of the two sliding frames, the placement box is located on the lower side of the fixed plate, an expansion mechanism for widening the nap area is provided on the fixed plate, and a support mechanism for supporting the expansion mechanism is connected between the expansion mechanism and the fixed plate.

[0007] As an improvement of the above-mentioned scheme, the expansion mechanism includes an expansion plate, a guide block and a handle. Guide blocks are slidably provided on the left and right sides of the fixed plate. An expansion plate for students to lie flat is connected between the two guide blocks. The expansion plate is slidably connected to the fixed plate, and a handle is provided in the middle of the rear of the expansion plate.

[0008] As an improvement of the above-mentioned scheme, the supporting mechanism includes a magnet, a supporting leg, a first supporting frame, a first rotating shaft, a first torsion spring and a first limit block. Magnets are provided on the left and right sides of the lower part of the fixed plate, two first supporting frames are provided on the left and right rear sides of the lower part of the expansion plate, there are four first supporting frames, a first rotating shaft is rotatably provided between the two first supporting frames on the same side, and supporting legs for supporting the expansion plates are provided on the two first rotating shafts. The magnet magnetically attracts the supporting legs on the same side, and first limit blocks are provided on the left and right rear sides of the lower part of the expansion plate. First torsion springs are connected between the left and right sides of the supporting legs and the adjacent first supporting frames. There are four first torsion springs, and the first torsion springs are wound around the first rotating shaft.

[0009] As an improvement of the above scheme, it also includes a guardrail mechanism to prevent students from slipping, the guardrail mechanism includes a collecting plate, a first guardrail, a second guardrail, a telescopic rod, a first spring, a second support frame, a connecting plate, a first sliding rod, a second spring and a wedge block, collecting plates are provided on the left and right sides of the fixed plate, two telescopic rods are provided on the front and back sides of the bottom of the collecting plate, there are eight telescopic rods, a first guardrail is connected between the upper sides of the four telescopic rods on the same side, the first guardrail is slidably connected to the collecting plate on the same side, a second guardrail is slidably provided in the two first guardrails, and the second guardrail is slidably connected to the expansion plate Two first springs are connected between the front and rear sides of the lower part of the first guardrail and the adjacent collecting plates, there are eight first springs, and the first springs are wound on the telescopic rod. A second support frame is provided on the inner rear side of the two collecting plates, and a first sliding rod is slidably provided on the front and rear sides of the second support frame. There are four first sliding rods, a connecting plate is connected between the inner sides of two adjacent first sliding rods, a wedge block is connected between the outer sides of two adjacent first sliding rods, and second springs are connected between the front and rear sides of the wedge block and the adjacent second supporting frames, there are four second springs, and the second springs are wound on the first sliding rod.

[0010] As an improvement of the above scheme, it also includes a locking mechanism for locking the expansion board, the locking mechanism includes a third support frame, a first locking tube, a third spring and a connecting tube, third support frames are provided on the rear sides of the left and right sides of the lower part of the fixed plate, first locking tubes are slidably provided on the two third support frames, third springs are connected between the two first locking tubes and the third support frames on the same side, the third spring is wound around the first locking tube, and a connecting tube is connected between the two first locking tubes.

[0011] As an improvement of the above scheme, it also includes a lifting mechanism for adjusting the height of the fixed plate, the lifting mechanism includes a second sliding rod, a connecting frame, a second clamping tube and a fourth spring, a second sliding rod is provided on the lower right side of the two supports, a connecting frame is slidably provided between the two second sliding rods, a second clamping tube is provided on the upper left and right sides of the connecting frame, the second clamping tube is slidably connected to the support on the same side, a fourth spring is connected between the left and right sides of the connecting frame and the support on the same side, and the fourth spring is wound around the second clamping tube.

[0012] As an improvement of the above scheme, it also includes a foot support mechanism for people to place their feet, the foot support mechanism includes a slider, a second limit block, a foot support plate, a second rotating shaft and a second torsion spring, a slider is slidably provided on the lower side of the fixed plate, a second limit block is provided on the upper front side of the slider, a second rotating shaft is rotatably provided on the upper side of the second limit block, a foot support plate is provided on the second rotating shaft, second torsion springs are connected between the left and right sides of the foot support plate and the second limit block, and the second torsion spring is wound around the second rotating shaft.

[0013] As an improvement of the above solution, through holes are provided on the front sides of the left and right sides of the expansion board.

[0014] The advantages of the present invention are as follows: 1. The present invention allows people to manually move the handle backwards, thereby causing the guide block and the expansion plate to move backwards. When the fixed plate blocks the guide block, people stop moving the handle, and then people lie flat on the expansion plate and the fixed plate for a nap, thereby achieving the effect of lying flat for a nap;

[0015] 2. The expansion plate moves backwards and drives the second guardrail to move backwards. When the second guardrail contacts the connecting plate on the same side, the compressed first spring resets and drives the first guardrail and the second guardrail to move upwards, thereby achieving the effect of a guardrail and preventing students from slipping off the expansion plate and the fixed plate during a nap;

[0016] 3. The expansion board moves backward, driving the through hole to move backward. When the through hole and the first clamping tube on the same side are on the same vertical line, the stretched third spring resets and drives the first clamping tube to move upward, thereby causing the connecting tube to move upward, thereby achieving a clamping effect and preventing the expansion board from moving easily. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the three-dimensional structure from the first viewing angle of the present invention.

[0018] Figure 2 It is a partial three-dimensional structural schematic diagram of the present invention.

[0019] Figure 3 It is a schematic diagram of the three-dimensional structure from a second viewing angle of the present invention.

[0020] Figure 4 It is a schematic diagram of the three-dimensional structure from a third viewing angle of the present invention.

[0021] Figure 5 It is a schematic cross-sectional three-dimensional structural diagram of the expansion mechanism of the present invention.

[0022] Figure 6 It is a schematic diagram of the three-dimensional structure of the support mechanism of the present invention.

[0023] Figure 7 It is an enlarged view of point A of the present invention.

[0024] Figure 8 It is a schematic diagram of the three-dimensional structure of the guardrail mechanism of the present invention.

[0025] Fig. 9 It is a schematic diagram of the cross-sectional three-dimensional structure of the guardrail mechanism of the present invention.

[0026] Fig.10 It is a partial diagram of the guardrail mechanism of the present invention.

[0027] Fig.11 It is an enlarged view of B of the present invention.

[0028] Fig.12 It is a schematic diagram of the three-dimensional structure of the first part of the locking mechanism of the present invention.

[0029] Fig.13 It is a schematic diagram of the three-dimensional structure of the second part of the locking mechanism of the present invention.

[0030] Fig.14 It is a schematic diagram of the three-dimensional structure of the lifting mechanism of the present invention.

[0031] Fig.15 It is a schematic diagram of the three-dimensional structure of the first part of the foot support mechanism of the present invention.

[0032] Fig.16 It is an enlarged view of location C of the present invention.

[0033] Fig.17 It is a schematic diagram of the three-dimensional structure of the second part of the foot support mechanism of the present invention.

[0034] In the accompanying drawings: 1-support, 2-sliding frame, 3-placing box, 4-fixed plate, 5-extension mechanism, 51-extension plate, 52-guide block, 53-handle, 6-support mechanism, 61-magnet, 62-support leg, 63-first support frame, 64-first rotating shaft, 65-first torsion spring, 66-first limit block, 7-guardrail mechanism, 71-collection plate, 72-first guardrail, 73-second guardrail, 74-telescopic rod, 75-first spring, 76-second support Frame, 77-connecting plate, 78-first slide bar, 79-second spring, 710-wedge block, 8-locking mechanism, 81-third support frame, 82-first locking tube, 83-third spring, 84-connecting tube, 9-lifting mechanism, 91-second slide bar, 92-connecting frame, 93-second locking tube, 94-fourth spring, 10-supporting mechanism, 101-slider, 102-second limiting block, 103-supporting plate, 104-second rotating shaft, 105-second torsion spring. DETAILED DESCRIPTION

[0035] Below, the present invention is further described in conjunction with the accompanying drawings and specific embodiments:

[0036] Example 1

[0037] A desk that is convenient for primary and secondary school students to take a nap, now for reference Figure 1-4 , including a support 1, a sliding frame 2, a placement box 3, a fixed plate 4, an expansion mechanism 5 and a supporting mechanism 6. The two supports 1 are slidably provided with sliding frames 2, a fixed plate 4 is connected between the upper sides of the two sliding frames 2, a placement box 3 is connected between the two sliding frames 2, the placement box 3 is located at the lower side of the fixed plate 4, an expansion mechanism 5 is provided on the fixed plate 4, and a supporting mechanism 6 is connected between the expansion mechanism 5 and the fixed plate 4.

[0038] Reference Figure 3 , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Fig.12 and Fig.13 The expansion mechanism 5 includes an expansion plate 51, a guide block 52 and a handle 53. The guide blocks 52 are slidably provided on the left and right sides of the fixed plate 4. The expansion plate 51 is fixedly connected between the two guide blocks 52 by bolts. Through holes are opened on the left and right front sides of the expansion plate 51. The expansion plate 51 is slidably connected to the fixed plate 4, and a handle 53 is welded in the middle of the rear of the expansion plate 51.

[0039] Reference Figure 3 , Figure 4 , Figure 6 and Figure 7 The supporting mechanism 6 includes a magnet 61, a supporting leg 62, a first supporting frame 63, a first rotating shaft 64, a first torsion spring 65 and a first limiting block 66. Magnets 61 are provided on both left and right sides of the lower part of the fixed plate 4. Two first supporting frames 63 are fixedly connected by bolts on the left and right sides of the lower part of the extension plate 51. There are four first supporting frames 63. A first rotating shaft 64 is rotatably provided between the two first supporting frames 63 on the same side. Support legs 62 are provided on the two first rotating shafts 64. The magnet 61 magnetically attracts the supporting legs 62 on the same side. The first limiting blocks 66 are fixedly connected by bolts on the left and right sides of the lower part of the extension plate 51. The supporting legs 62 contact the first limiting blocks 66 on the same side. First torsion springs 65 are connected between the left and right sides of the supporting legs 62 and the adjacent first supporting frames 63. There are four first torsion springs 65, which are wound around the first rotating shaft 64.

[0040] When people need to use a desk that is convenient for taking a nap, people can use this desk that is convenient for primary and secondary school students to take a nap. When people are in class, people can place books in the storage box 3 for storage. When people need to take a nap, people can manually move the handle 53 backward, so that the expansion plate 51 moves backward, so that the guide block 52 and the support leg 62 move backward. When the fixing plate 4 clamps the guide block 52, people stop moving the handle 53. At this time, the magnetic force of the magnet 61 on the support leg 62 is small, so that the torsionally deformed first torsion spring 65 is reset to drive the support leg 62 to rotate to contact the ground, thereby causing the first rotating shaft 64 to rotate. When the support leg 62 rotates to 90 degrees, the first limit block 66 and the support leg 62 on the same side are locked. When the support leg 62 is in contact with the first limit block 66, the first limit block 66 limits the support leg 62 and prevents the support leg 62 from rotating too much. At this time, people lie on the fixed plate 4 and the expansion plate 51 for a nap. When people finish their nap, they rotate the support leg 62 in the opposite direction, so that the first rotating shaft 64 rotates in the opposite direction, causing the first torsion spring 65 to twist and deform. After the support leg 62 rotates 90 degrees in the opposite direction, people manually move the handle 53 forward, so that the expansion plate 51 moves forward, causing the guide block 52 and the support leg 62 to move forward. When the support leg 62 contacts the magnet 61 on the same side, the magnet 61 magnetically attracts the support leg 62 on the same side. When the guide block 52 moves forward and is stuck by the fixed plate 4, people stop moving the handle 53 forward.

[0041] Example 2

[0042] Based on Example 1, now refer to Figure 3 , Figure 4 , Figure 8 , Fig. 9 , Fig.10 and Fig.11, also includes a guardrail mechanism 7, the guardrail mechanism 7 includes a collecting plate 71, a first guardrail 72, a second guardrail 73, a telescopic rod 74, a first spring 75, a second support frame 76, a connecting plate 77, a first sliding rod 78, a second spring 79 and a wedge block 710, the left and right sides of the fixed plate 4 are provided with collecting plates 71, the front and rear sides of the bottom of the collecting plate 71 are provided with two telescopic rods 74, there are eight telescopic rods 74, the first guardrail 72 is connected between the upper sides of the four telescopic rods 74 on the same side, the first guardrail 72 is slidably connected to the collecting plate 71 on the same side, the two first guardrails 72 are slidably provided with second guardrails 73, the second guardrail 73 is slidably connected to the expansion plate 51, the front and rear sides of the lower part of the first guardrail 72 are connected to the adjacent collecting plates 71 There are two first springs 75, there are eight first springs 75, the first springs 75 are wound around the telescopic rod 74, the inner rear side of the two collecting plates 71 are fixed with second support frames 76 by bolts, the second support frames 76 are slidably provided with first slide bars 78 on the upper sides of the front and rear sides, there are four first slide bars 78, a connecting plate 77 is welded between the inner sides of two adjacent first slide bars 78, the second guardrail 73 contacts with the connecting plate 77 on the same side after moving, a wedge block 710 is connected between the outer sides of two adjacent first slide bars 78, the wedge block 710 contacts the first guardrail 72 on the same side, and second springs 79 are connected between the front and rear sides of the wedge block 710 and the adjacent second support frames 76, there are four second springs 79, and the second springs 79 are wound around the first slide bar 78.

[0043] Reference Figure 3 , Fig.12 and Fig.13 , also includes a locking mechanism 8, the locking mechanism 8 includes a third support frame 81, a first locking tube 82, a third spring 83 and a connecting tube 84, the third support frames 81 are fixedly connected to the rear sides of the left and right sides of the lower part of the fixed plate 4 by bolts, and the two third support frames 81 are slidably provided with a first locking tube 82, and the through holes contact the first locking tube 82 on the same side after moving, and the third spring 83 is connected between the two first locking tubes 82 and the third support frame 81 on the same side, the third spring 83 is wound around the first locking tube 82, and a connecting tube 84 is connected between the two first locking tubes 82.

[0044] Reference Figure 3 , Figure 4 and Fig.14, also includes a lifting mechanism 9, the lifting mechanism 9 includes a second sliding rod 91, a connecting frame 92, a second clamping tube 93 and a fourth spring 94, the second sliding rods 91 are welded on the lower right side of the two supports 1, a connecting frame 92 is slidably provided between the two second sliding rods 91, and second clamping tubes 93 are provided on the upper left and right sides of the connecting frame 92. The second clamping tube 93 is slidably connected to the support 1 on the same side, and the second clamping tube 93 contacts the sliding frame 2 on the same side. Fourth springs 94 are connected between the left and right sides of the connecting frame 92 and the support 1 on the same side, and the fourth spring 94 is wound around the second clamping tube 93.

[0045] Reference Figure 4 , Fig.15 , Fig.16 and Fig.17 , also includes a foot support mechanism 10, the foot support mechanism 10 includes a slider 101, a second limit block 102, a foot support plate 103, a second rotating shaft 104 and a second torsion spring 105, a slider 101 is slidably provided on the lower side of the fixed plate 4, a second limit block 102 is welded on the upper front side of the slider 101, a second rotating shaft 104 is rotatably provided on the upper side of the second limit block 102, a foot support plate 103 is provided on the second rotating shaft 104, the foot support plate 103 is in contact with the fixed plate 4, and the foot support plate 103 contacts with the second limit block 102 after rotation, second torsion springs 105 are connected between the left and right sides of the foot support plate 103 and the second limit block 102, and the second torsion spring 105 is wound around the second rotating shaft 104.

[0046] The expansion plate 51 moves backward and drives the second guardrail 73 to move backward. When the second guardrail 73 moves backward and contacts the connecting plate 77 on the same side, the second guardrail 73 drives the connecting plate 77 on the same side to move inward, thereby causing the first slide bar 78 to move inward, causing the wedge block 710 to move inward, and the second spring 79 is compressed. When the wedge block 710 moves inwardly away from the first guardrail 72 on the same side, the compressed first spring 75 resets and drives the first guardrail 72 to move upward, thereby causing the second guardrail 73 to move upward, and the telescopic rod 74 is stretched. When the second guardrail 73 moves upward away from the connecting plate 77 on the same side, the second spring 79 resets and drives the wedge block 710 to move outward and reset, thereby causing the first slide bar 78 and the connecting plate 77 to move outward, thereby achieving a protective effect and preventing people from falling from the fixed plate 4 and the expansion plate 51 during a nap. When people finish their nap, they can manually move the first When the wedge block 710 moves outward and contacts the first guardrail 72 on the same side, the wedge block 710 is clamped by the first guardrail 72.

[0047] The expansion plate 51 moves backward, driving the through hole backward. When the through hole is on the same vertical line as the first clamping tube 82 on the same side, the stretched third spring 83 is reset, driving the first clamping tube 82 to move upward and contact the through hole on the same side, so that the connecting tube 84 moves upward, thereby achieving a clamping effect and preventing the expansion plate 51 from being easily moved. When people need to move the expansion plate 51 forward, they manually move the connecting tube 84 downward, thereby causing the first clamping tube 82 to move downward, causing the third spring 83 to be stretched. When the first clamping tube 82 is away from the through hole on the same side, people can move the expansion plate 51 forward, and then release the connecting tube 84. At this time, the third spring 83 is in a stretched state.

[0048] When people need to lower the height of the fixing plate 4, they can manually move the connecting frame 92 to the right, so that the second clamping tube 93 moves to the right and the fourth spring 94 is stretched. When the second clamping tube 93 is away from the sliding frame 2 on the same side, people can manually move the fixing plate 4 downward, so that the sliding frame 2 moves downward. When the fixing plate 4 moves to a suitable position, people release the connecting frame 92, so that the fourth spring 94 resets and drives the connecting frame 92 to move to the left, so that the second clamping tube 93 moves to the left and clamps the sliding frame 2 on the same side, thereby achieving the adjustment effect. When people need to increase the height of the fixing plate 4, after moving the connecting frame 92 to the right according to the above operation, people manually move the fixing plate 4 upward. When the fixing plate 4 moves to a suitable position, people release the connecting frame 92.

[0049] After people move the expansion plate 51 backward, they manually move the slider 101 forward, so that the second limit block 102 moves forward, and the foot support plate 103 moves forward. When the foot support plate 103 moves away from the fixed plate 4, the torsionally deformed second torsion spring 105 is reset to drive the foot support plate 103 to rotate and reset, so that the second rotating shaft 104 rotates. When the foot support plate 103 rotates to contact with the second limit block 102, the foot support plate 103 stops rotating, and then people can place their feet on the foot support plate 103. When people finish their lunch break, they manually rotate the foot support plate 103 in the opposite direction, so that the second torsion spring 105 is torsionally deformed, so that the second rotating shaft 104 rotates in the opposite direction. When the foot support plate 103 rotates to a horizontal state, people move the slider 101 backward, so that the second limit block 102 and the foot support plate 103 move backward, and then the foot support plate 103 contacts with the fixed plate 4.

[0050] For those skilled in the art, various other corresponding changes and deformations can be made according to the technical solutions and concepts described above, and all of these changes and deformations should fall within the protection scope of the claims of the present invention.

Claims

1. A desk for primary and secondary school students to take a nap, comprising a support (1), a sliding frame (2), a storage box (3) and a fixed plate (4), wherein the two supports (1) are both provided with sliding frames (2) in a sliding manner, the storage box (3) is connected between the two sliding frames (2), the fixed plate (4) is connected between the upper sides of the two sliding frames (2), and the storage box (3) is located at the lower side of the fixed plate (4), characterized in that: It also includes an expansion mechanism (5) and a support mechanism (6), wherein the fixed plate (4) is provided with the expansion mechanism (5) for widening the napping area, and the support mechanism (6) for supporting the expansion mechanism (5) is connected between the expansion mechanism (5) and the fixed plate (4); The expansion mechanism (5) comprises an expansion plate (51), a guide block (52) and a handle (53); guide blocks (52) are slidably provided on both left and right sides of the fixed plate (4); an expansion plate (51) for students to lie flat is connected between the two guide blocks (52); the expansion plate (51) is slidably connected to the fixed plate (4); and a handle (53) is provided in the middle of the rear of the expansion plate (51); The support mechanism (6) comprises a magnet (61), a support leg (62), a first support frame (63), a first rotating shaft (64), a first torsion spring (65) and a first stop block (66). Magnets (61) are provided on both left and right sides of the lower part of the fixed plate (4). Two first support frames (63) are provided on both left and right sides of the lower part of the expansion plate (51), and there are four first support frames (63). A first rotating shaft (64) is rotatably provided between the two first support frames (63) on the same side. Support legs (62) for supporting the expansion plate (51) are provided on the two first rotating shafts (64). The magnet (61) magnetically attracts the support legs (62) on the same side. First stop blocks (66) are provided on both left and right sides of the lower part of the expansion plate (51). First torsion springs (65) are connected between the left and right sides of the support legs (62) and the adjacent first support frames (63). There are four first torsion springs (65), and the first torsion springs (65) are wound around the first rotating shaft (64). The device also includes a guardrail mechanism (7) for preventing students from slipping. The guardrail mechanism (7) includes a collecting plate (71), a first guardrail (72), a second guardrail (73), a telescopic rod (74), a first spring (75), a second support frame (76), a connecting plate (77), a first sliding rod (78), a second spring (79) and a wedge block (710). The fixing plate (4) is provided with a collecting plate (71) on both sides. Two telescopic rods (74) are provided on both sides of the inner bottom of the collecting plate (71). There are eight telescopic rods (74). The upper sides of the four telescopic rods (74) on the same side are connected with a first guardrail (72). The first guardrail (72) is slidably connected to the collecting plate (71) on the same side. The two first guardrails (72) are slidably provided with a second guardrail (73). The second guardrail (73) is slidably connected to the expansion plate (51). Then, two first springs (75) are connected between the front and rear sides of the lower part of the first guardrail (72) and the adjacent collecting plate (71), and the number of the first springs (75) is eight. The first springs (75) are wound around the telescopic rod (74). The inner side of the two collecting plates (71) is provided with a second support frame (76) at the rear side. The upper side of the front and rear sides of the second support frame (76) is provided with a first slide bar (78) in a sliding manner. The number of the first slide bars (78) is four. A connecting plate (77) is connected between the inner sides of the two adjacent first slide bars (78). A wedge block (710) is connected between the outer sides of the two adjacent first slide bars (78). The front and rear sides of the wedge block (710) and the adjacent second supporting frame (76) are connected with a second spring (79). The number of the second springs (79) is four. The second spring (79) is wound around the first slide bar (78); It also includes a locking mechanism (8) for locking the expansion plate (51), the locking mechanism (8) including a third support frame (81), a first locking tube (82), a third spring (83) and a connecting tube (84), the third support frames (81) are each provided at the rear side of the left and right sides of the lower part of the fixed plate (4), the first locking tube (82) is slidably provided on the two third support frames (81), the third spring (83) is connected between the two first locking tubes (82) and the third support frame (81) on the same side, the third spring (83) is wound around the first locking tube (82), and the connecting tube (84) is connected between the two first locking tubes (82).

2. A desk for primary and secondary school students to take a nap as claimed in claim 1, characterized in that: The invention also comprises a lifting mechanism (9) for adjusting the height of the fixing plate (4), the lifting mechanism (9) comprising a second sliding rod (91), a connecting frame (92), a second clamping tube (93) and a fourth spring (94), the second sliding rod (91) being provided at the lower right side of the two supports (1), the connecting frame (92) being provided between the two second sliding rods (91) in a sliding manner, the second clamping tube (93) being provided at the upper left and right sides of the connecting frame (92), the second clamping tube (93) being slidably connected to the support (1) on the same side, the fourth spring (94) being connected between the left and right sides of the connecting frame (92) and the support (1) on the same side, and the fourth spring (94) being wound around the second clamping tube (93).

3. A desk for primary and secondary school students to take a nap as claimed in claim 2, characterized in that: The invention also comprises a foot support mechanism (10) for people to place their feet. The foot support mechanism (10) comprises a slider (101), a second limit block (102), a foot support plate (103), a second rotating shaft (104) and a second torsion spring (105). The slider (101) is slidably provided on the lower side of the fixed plate (4). The second limit block (102) is provided on the upper front side of the slider (101). The second rotating shaft (104) is rotatably provided on the upper side of the second limit block (102). The foot support plate (103) is provided on the second rotating shaft (104). The second torsion spring (105) is connected between the left and right sides of the foot support plate (103) and the second limit block (102). The second torsion spring (105) is wound around the second rotating shaft (104).

4. A desk for primary and secondary school students to take a nap as claimed in claim 1, characterized in that: Through holes are provided on the front sides of the left and right sides of the expansion plate (51).

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