Blackboard eraser

Abstract

The utility model relates to the field of teaching aids, in particular to a blackboard eraser. Comprising a shell, openings are formed in the upper end and the lower end of the shell, slotted holes are formed in the front side and the rear side of the shell, a cuboid inner block is placed in the shell, wiping assemblies are fixed to the upper side, the lower side, the front side and the rear side of the inner block, connecting blocks are fixed to the left end and the right end of the inner block, inner cross-shaped grooves are formed in the left end and the right end of the shell, and inner sliding rods are fixed to the connecting blocks; the inner sliding rod is clamped in the inner cross groove in a sliding mode, and positioning assemblies for positioning the inner sliding rod are arranged at the left end and the right end of the shell correspondingly. The inner block is arranged in the shell, and the wiping assemblies are arranged on the periphery of the inner block. Therefore, the wiping area of the blackboard eraser can be increased. In the using process, the positions of the inner block and the wiping assemblies can be adjusted, chalk handwriting on the blackboard can be wiped through the different wiping assemblies, and the chalk handwriting on the blackboard can be effectively wiped away.

Description

Technical Field

[0001] The utility model relates to the field of teaching tools, in particular to a blackboard eraser. Background Art

[0002] Blackboard erasers are widely used in teaching. Currently, the commonly used blackboard erasers have a simple structure, generally in the shape of a rectangular block. In actual use, dust is generated when wiping the chalk marks on the blackboard. Chalk dust is inhaled into the lungs and causes harm to the body.

[0003] In order to prevent chalk dust from flying in the classroom, a wet blackboard eraser is used in the process of wiping the blackboard. The wet blackboard eraser is soaked with water, and the chalk dust can be effectively prevented from flying when the wet blackboard eraser is used to wipe the chalk handwriting on the blackboard. However, in the process of wiping the blackboard with a wet blackboard eraser, chalk dust is constantly accumulated on the wet blackboard eraser's wiper. After the wet blackboard eraser is inserted through the blackboard, white scratches are likely to remain on the blackboard. It is necessary to use tools such as rags to thoroughly clean the blackboard. At the same time, the teacher needs to use the blackboard eraser frequently during the blackboard writing process. As the chalk dust on the blackboard eraser's wiper continues to accumulate, it is inconvenient for the teacher to use it during the blackboard writing process.

[0004] In the prior art, a patent document with application number CN201920940719.1 and titled "A wet blackboard eraser that is easy to clean and replace" discloses a wet blackboard eraser in which the wiping cloth and the blackboard eraser body are detachably connected, which is convenient for cleaning and replacement. When a lot of chalk dust accumulates on the wiping cloth, the wiping cloth needs to be disassembled and replaced, and replacing the wiping cloth takes up class time, which is inconvenient to use.

[0005] The patent document with application number CN201921487950.6 and titled "An Environmentally Friendly Blackboard Eraser" discloses a blackboard eraser that can store multiple wipes. The back of the blackboard eraser is provided with multiple storage compartments, which are used to place clean or dirty wet cotton cloth and absorbent cotton for wiping. When the wipes of the blackboard eraser accumulate a lot of chalk dust, they also need to be replaced manually. Utility Model Content

[0006] The technical problem to be solved by the utility model is to provide a blackboard eraser which can increase the wiping area, is convenient to use and can ensure that chalk writings on the blackboard can be effectively erased during class.

[0007] In order to achieve the above purpose, the technical solution provided by the utility model is:

[0008] The invention discloses a blackboard eraser, comprising a shell, the upper and lower ends of the shell are open, the front and rear sides of the shell are provided with slots, a rectangular inner block is placed in the shell, the upper and lower sides and the front and rear sides of the inner block are fixed with wiping components, the left and right ends of the inner block are fixed with connecting blocks, the left and right ends of the shell are provided with inner cross grooves, the connecting blocks are fixed with inner sliding rods, the inner sliding rods are slidably engaged in the inner cross grooves, and the left and right ends of the shell are provided with positioning components for positioning the inner sliding rods.

[0009] Specifically, the positioning assembly includes a plurality of support rods fixed on the shell, and the plurality of support rods are fixedly connected by a fixing plate, an outer cross groove corresponding to the inner cross groove is opened on the fixing plate, an outer sliding rod is slidably clamped in the outer cross groove, the outer sliding rod is concentric with the inner sliding rod, the outer sliding rod passes through the outer cross groove, a pressing plate is fixed to one end of the outer sliding rod, a positioning plate is fixed to the other end of the outer sliding rod, the positioning plate is tightly against the fixing plate, an insertion rod is fixed on the positioning plate, a blind hole is opened on one end of the inner sliding rod toward the insertion rod, the insertion rod is slidably inserted in the blind hole, a spring is installed between the insertion rod and the bottom of the blind hole, and the spring is tightly against the insertion rod.

[0010] Compared with the prior art, the beneficial effects of the utility model are:

[0011] 1. The utility model sets an inner block in the housing, and wiping components are set around the inner block. Therefore, the wiping area of ​​the blackboard eraser can be increased. During use, the positions of the inner block and the wiping components can be adjusted, and different wiping components can be used to wipe the chalk writing on the blackboard, which can effectively erase the chalk writing on the blackboard.

[0012] 2. The inner block is easy to position. Pressing the two pressing plates at the same time can adjust the position of the inner block and the wiping assembly in the shell. After releasing the pressing plates, the positioning plate can be pressed against the fixed plate on one side of it, and the inner block and the wiping assembly are positioned, which makes it convenient to use different wiping assemblies to wipe the blackboard, and is easy to use.

[0013] 3. After using the blackboard eraser, since the upper and lower sides of the shell are opened, the front and rear sides of the shell are provided with slots, which is convenient for rinsing the four wiping components.

[0014] 4. When using this blackboard eraser, hold the shell to avoid water stains or chalk dust on the wiping component from sticking to the user's hands. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the utility model.

[0016] Figure 2 It is a cross-sectional view of the utility model.

[0017] Figure 3 for Figure 2 Magnified view of area A.

[0018] The names of the parts in the attached drawings are:

[0019] 1 Housing

[0020] 2 slots

[0021] 3 Inner Block

[0022] 301 Sponge Layer

[0023] 302 Wipe

[0024] 4 Internal cross slot

[0025] 5 Inner slider

[0026] 6 rods

[0027] 7 Fixing plate

[0028] 8 External cross slot

[0029] 9 Outer Slide

[0030] 10 Press plate

[0031] 11 Positioning plate

[0032] 12 Connection block

[0033] 13 Insert the rod

[0034] 14 Spring. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0036] Embodiment 1:

[0037] Reference Figure 1-Figure 3 As shown, the blackboard eraser comprises a shell 1, the upper and lower ends of the shell 1 are open, and slots 2 are provided on both the front and rear sides of the shell 1.

[0038] An inner block 3 in the shape of a rectangular parallelepiped is placed in the housing 1 , and wiping components are fixed on the upper and lower sides and the front and rear sides of the inner block 3 .

[0039] The wiping assembly includes a sponge layer 301, which is fixedly connected to the inner block 3, and a wiping cloth 302 is attached to the side of the sponge layer 301 away from the inner block 3. The sponge layer 301 can absorb water, and when the wiping cloth 302 is used to wipe the blackboard, the water in the sponge layer 301 can enter the wiping cloth 302 to provide moisture to the wiping cloth 302.

[0040] The left and right ends of the inner block 3 are fixed with connecting blocks 12, the left and right ends of the housing 1 are provided with inner cross grooves 4, the connecting blocks 12 are fixed with inner slide bars 5, and the inner slide bars 5 are slidably engaged in the inner cross grooves 4. The inner slide bars 5 are square bars, and the inner slide bars 5 can only slide in the inner cross grooves 4.

[0041] Positioning components for positioning the inner slide bar 5 are provided at both left and right ends of the housing 1 .

[0042] The positioning assembly includes a plurality of support rods 6 fixed on the housing 1, and the plurality of support rods 6 are fixedly connected by a fixing plate 7. An outer cross groove 8 corresponding to the inner cross groove 4 is provided on the fixing plate 7, and an outer slide bar 9 is slidably engaged in the outer cross groove 8, and the outer slide bar 9 is concentric with the inner slide bar 5. The outer slide bar 9 is a square rod. The outer slide bar 9 passes through the outer cross groove 8. A pressing plate 10 is fixed to one end of the outer slide bar 9, and a positioning plate 11 is fixed to the other end of the outer slide bar 9, and the positioning plate 11 is tightly against the fixing plate 7. Anti-slip patterns are processed on the opposite end faces of the fixing plate 7 and the positioning plate 11. The anti-slip patterns can increase the friction between the fixing plate 7 and the positioning plate 11.

[0043] An insertion rod 13 is fixed on the positioning plate 11, and a blind hole is formed at one end of the inner sliding rod 5 facing the insertion rod 13. The insertion rod 13 is slidably inserted in the blind hole, and a spring 14 is installed between the insertion rod 13 and the bottom of the blind hole, and the spring 14 is pressed against the insertion rod 13. Under the elastic force of the spring 14, the positioning plate 11 is pressed against the fixed plate 7 to position the inner block 3 and the wiping assembly.

[0044] When in use, the pressing plates 10 on both sides are pressed simultaneously, so that the insertion rod 13 moves toward the inside of the housing 1 and compresses the spring 14. When the positioning plate 11 is separated from the fixing plate 7, the inner slider can move in the inner cross groove 4. At the same time, the outer slider 9 moves in the outer cross groove 8, and the positions of the inner block 3 and the wiping assembly in the housing 1 are changed.

[0045] The inner slide bar 5 moves downward in the inner cross groove 4. When the inner slide bar 5 contacts the lower groove wall of the inner cross groove 4, the wiping assembly on the lower side of the inner block 3 protrudes to the lower side of the housing 1. At the same time, the outer slide bar 9 is located at the lower side of the outer cross groove 8. Then the pressing plate 10 is released, and the positioning plate 11 can be pressed against the fixing plate 7 under the elastic force of the spring 14. After the fixing plate 7 is pressed against the positioning plate 11, the inner block 3 and the wiping assembly can be fixed in the housing 1. At this time, the wiping assembly on the lower side of the inner block 3 can be used to wipe the chalk marks on the blackboard.

[0046] The inner slide bar 5 moves upward in the inner cross groove 4. When the inner slide bar 5 contacts the upper groove wall of the inner cross groove 4, the wiping assembly on the upper side of the inner block 3 protrudes to the upper side of the housing 1. Then the pressing plate 10 is released. At this time, the wiping assembly on the upper side of the inner block 3 can be used to wipe the chalk marks on the blackboard.

[0047] The inner slide bar 5 moves forward in the inner cross groove 4. When the inner slide bar 5 contacts the front groove wall of the inner cross groove 4, the wiping assembly on the front side of the inner block 3 passes through the slot hole 2 on the front side of the housing 1 and protrudes to the front side of the housing 1. Then the pressing plate 10 is released. At this time, the wiping assembly on the front side of the inner block 3 can be used to wipe the chalk marks on the blackboard.

[0048] The inner slide bar 5 moves in the inner cross groove 4 toward the rear side. When the inner slide bar 5 contacts the rear groove wall of the inner cross groove 4, the wiping assembly on the rear side of the inner block 3 passes through the slot hole 2 on the rear side of the housing 1 and protrudes to the rear side of the housing 1. Then the pressing plate 10 is released. At this time, the wiping assembly on the rear side of the inner block 3 can be used to wipe the chalk marks on the blackboard.

[0049] During use, the wiping components at different positions are used to wipe the chalk writing on the blackboard, which can increase the wiping area of ​​the blackboard eraser. The chalk writing on the blackboard can be effectively erased, and white scratches can be avoided on the blackboard. There is no need to replace the wiping cloth 302, and the chalk dust on the wiping cloth 302 can be avoided from getting on the hands.

[0050] After the blackboard eraser is used, since the upper and lower sides of the shell 1 are open, the front and rear sides of the shell 1 are both provided with slots 2, which is convenient for washing the four wiping components.

[0051] When using the blackboard eraser, the user can hold the housing 1 to prevent water stains or chalk dust on the wiping component from adhering to the user's hands.

[0052] Embodiment 2:

[0053] Based on Example 1, refer to Figure 2 As shown, a sub-velcro tape is fixed on the wiping cloth 302, and a main velcro tape is fixed on the sponge layer 301, and the sub-velcro tape and the main velcro tape are bonded and fixed.

[0054] When the wiping cloth 302 is damaged, it is convenient to disassemble the wiping cloth 302 for replacement.

[0055] In the description of the present invention, it should be understood that the terms "coaxial", "bottom", "one end", "top", "middle", "the other end", "upper", "one side", "top", "inside", "front", "center", "both ends" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0056] The present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention. In order to make the public have a thorough understanding of the present invention, specific details are described in detail in the following preferred embodiments of the present invention, and those skilled in the art can fully understand the present invention without the description of these details. In addition, in order to avoid unnecessary confusion about the essence of the present invention, well-known methods, processes, procedures, components and circuits are not described in detail.

[0057] A person skilled in the art will appreciate that all or part of the steps in the above-mentioned embodiment method can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc.

[0058] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A blackboard eraser, comprising a housing (1), wherein the housing (1) has openings at both ends, and wherein: The housing (1) is provided with slots (2) on both the front and rear sides. A rectangular inner block (3) is placed in the housing (1). Wiping components are fixed on both the upper and lower sides and the front and rear sides of the inner block (3). Connecting blocks (12) are fixed on both the left and right ends of the inner block (3). Internal cross grooves (4) are provided on both the left and right ends of the housing (1). Internal sliding rods (5) are fixed on the connecting blocks (12). The internal sliding rods (5) are slidably engaged in the internal cross grooves (4). Positioning components for positioning the internal sliding rods (5) are provided on both the left and right ends of the housing (1).

2. The blackboard eraser according to claim 1, characterized in that: The positioning assembly comprises a plurality of support rods (6) fixed on the housing (1), the plurality of support rods (6) being fixedly connected via a fixing plate (7), an outer cross groove (8) corresponding to the inner cross groove (4) being provided on the fixing plate (7), an outer slide rod (9) being slidably engaged in the outer cross groove (8), the outer slide rod (9) being concentric with the inner slide rod (5), the outer slide rod (9) passing through the outer cross groove (8), a pressing plate (10) being fixed at one end of the outer slide rod (9), a positioning plate (11) being fixed at the other end of the outer slide rod (9), the positioning plate (11) being tightly pressed against the fixing plate (7), an insertion rod (13) being fixed on the positioning plate (11), a blind hole being provided at one end of the inner slide rod (5) facing the insertion rod (13), the insertion rod (13) being slidably inserted in the blind hole, a spring (14) being installed between the insertion rod (13) and the bottom of the blind hole, the spring (14) being tightly pressed against the insertion rod (13).

3. The blackboard eraser according to claim 2, characterized in that: The inner sliding rod (5) and the outer sliding rod (9) are both square rods, and the inner sliding rod (5) can only slide in the inner cross groove (4).

4. The blackboard eraser according to claim 2, characterized in that: The opposite end surfaces of the fixing plate (7) and the positioning plate (11) are both processed with anti-slip patterns.

5. The blackboard eraser according to claim 1, characterized in that: The wiping assembly comprises a sponge layer (301), the sponge layer (301) is fixedly connected to the inner block (3), and a wiping cloth (302) is adhered to a side of the sponge layer (301) away from the inner block (3).

6. The blackboard eraser according to claim 5, characterized in that: A sub-velcro tape is fixed on the wiping cloth (302), and a main-velcro tape is fixed on the sponge layer (301), and the sub-velcro tape and the main-velcro tape are bonded and fixed.

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