Push-pull type environment-friendly blackboard

Abstract

The push-pull type environment-friendly blackboard comprises a frame body assembly and a board body assembly, the board body assembly comprises a white board, a fixed board and a sliding board, the white board and the fixed board are arranged on the rear side of the frame body assembly through an installation assembly, and the sliding board is arranged on the front side of the frame body assembly in a sliding mode; a connecting assembly is arranged between the sliding plate and the fixing plate, a dust collecting assembly is arranged at the position, corresponding to the connecting assembly, of the inner bottom of the frame assembly, a fixing assembly is arranged at the position, corresponding to the sliding plate, of the front side of the frame assembly, and the collecting assembly is movably arranged at the bottom of the fixing assembly; the connecting assembly and the fixing assembly are used for cleaning the fixing plate and the sliding plate correspondingly, and the dust collecting assembly and the collecting assembly are both used for collecting chalk dust.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of blackboards, in particular to a push-pull type environmentally friendly blackboard. BACKGROUND

[0002] As a traditional teaching and information display tool, the development of blackboards involves materials, structure, function evolution, and application in educational scenarios, etc. It can be sorted from the following dimensions: The material of the early blackboard is relatively simple, mostly wooden board surface coated with dark pigment (such as black or dark green paint), the purpose is to reduce reflection, protect vision, and facilitate chalk adhesion and wiping. Later, blackboards were gradually replaced by more stable materials. Among them, enamel steel plate became the mainstream blackboard substrate material in the mid-to-late 20th century because of its high hardness, wear resistance, corrosion resistance, and smooth surface for easy wiping. At the same time, coating technology has been continuously improved to improve writing smoothness, reduce reflection and dust. Dust-free improvement: Traditional blackboards use chalk to write, which produces a lot of dust, endangering the health of teachers and students. In the late 20th century, "dust-free chalk" (reducing dust flying by improving the formula) and "magnetic blackboard" (surface adsorbs magnetic teaching aids) appeared, thus promoting the development of erasable water-based pen compatible blackboards (similar to whiteboards, but retaining the large-area characteristics of blackboards).

[0003] The Chinese invention patent CN114347700B discloses a push-pull type blackboard with a blackboard eraser, which uses a motor as a driving force to move the sliding block and the transmission rod upward, and the transmission rod drives the fixed block and the cleaning eraser to move upward, so that the cleaning eraser wipes the text on the writing board, thus reducing manual wiping work and improving work efficiency.

[0004] However, in the above-mentioned application, the projection screen, electronic whiteboard and blackboard are separately arranged, which cannot realize the combination of traditional writing and multimedia teaching, and further causes the problem of mutual shielding when the multimedia content interaction function is combined with the blackboard.

[0005] Therefore, a push-pull type environmentally friendly blackboard is proposed to solve the above technical problems. SUMMARY

[0006] The present application aims to provide a push-pull type environmentally friendly blackboard to solve the technical problem that the existing blackboard and electronic whiteboard are separately designed, which occupies a large space and makes it difficult to use the device combination.

[0007] To achieve the above-mentioned purpose, the present application provides the following technical solutions: The utility model provides a kind of push-pull type environmental protection blackboard, including frame body assembly and board body assembly, the board body assembly includes whiteboard, fixed plate and sliding plate, the whiteboard and fixed plate are set to the rear side of the frame body assembly by mounting assembly, the sliding plate is slidably set to the front side of the frame body assembly, connecting assembly is arranged between the sliding plate and the fixed plate, the inner bottom of the frame body assembly is provided with dust collection assembly corresponding to the connecting assembly, the front side of the frame body assembly is provided with fixed component corresponding to the sliding plate, and the fixed component bottom is movably provided with the collection component;The connecting assembly and the fixed component are used for cleaning the fixed plate and the sliding plate respectively, and the dust collection assembly and the collection component are used for collecting chalk dust.

[0008] Further, the frame body assembly includes a top horizontal bar, a left side bar, a bottom horizontal bar, and a right side bar. Both sides of the top horizontal bar and the bottom horizontal bar are provided with adaptive slots. The end of the left side bar close to the top horizontal bar and the bottom horizontal bar is provided with a wedge block corresponding to the adaptive slots. The side of the right side bar close to the left side bar is also provided with a wedge block corresponding to the adaptive slots. The wedge block and the adaptive slots are movably connected. The top horizontal bar, the left side bar, the bottom horizontal bar, and the right side bar form a rectangular frame through the combination of the wedge block and the adaptive slots.

[0009] Further, the top of the top horizontal bar is provided with a top mounting slot, and the bottom of the bottom horizontal bar is provided with a bottom mounting slot. The front side of the top of the top horizontal bar is provided with a top sliding slot, and the front side of the top of the bottom horizontal bar is provided with a bottom sliding slot. The whiteboard, the fixed plate, and the sliding plate are fixedly connected with sliding protrusions at both ends of the top and the bottom. The two ends of the whiteboard are slidably connected with the top mounting slot and the bottom mounting slot through the sliding protrusions. The two ends of the fixed plate are slidably connected with the top mounting slot and the bottom mounting slot through the sliding protrusions. The two ends of the sliding plate are slidably connected with the top sliding slot and the bottom sliding slot through the sliding protrusions.

[0010] Further, the connecting assembly includes a fixed rod, a sliding seat, an inner blackboard eraser, a blocking key, a sliding slot, and a blocking slot. The sliding plate is fixedly installed with the fixed rod at the rear side. The fixed rod is slidably connected with the sliding seat. The sliding seat is installed with the inner blackboard eraser at the side close to the fixed plate. The end of the inner blackboard eraser away from the fixed rod is in abutment with the fixed plate. The bottom horizontal bar is provided with the blocking key corresponding to the sliding seat and the inner blackboard eraser. The sliding seat and the inner blackboard eraser are slidably arranged inside the blocking key.

[0011] Furthermore, the dust collecting assembly includes a dust collecting trough, a U-shaped frame, an electric telescopic rod, a compression spring and a support seat; the bottom cross bar is provided with a dust collecting trough corresponding to the connecting assembly, the U-shaped frame is slidably arranged in the dust collecting trough, one end of the U-shaped frame close to the right rod abuts against the sliding groove, the end of the U-shaped frame away from the right rod is connected to the electric telescopic rod, and the side wall of the dust collecting trough away from the right rod is installed with the support seat, the support seat is connected to the electric telescopic rod, and the compression spring is also provided between the support seat and the U-shaped frame, the compression spring is wound around the outside of the electric telescopic rod, and the compression spring keeps the electric telescopic rod close to the support seat; the horizontal length of the U-shaped frame is greater than the horizontal length of the fixed plate.

[0012] When cleaning the U-shaped frame, move the sliding groove to slide out of the right rod, and the dust collecting trough is connected with the blocking groove, and the electric telescopic rod drives the U-shaped frame to slide away from the support seat, and the U-shaped frame extends out of the right rod.

[0013] Furthermore, the fixed assembly includes a dust box, a convex cover plate, a rotating shaft and an outer blackboard eraser; the convex cover plate is slidably provided on the front side of the top cross bar, the convex cover plate is fixedly connected to the dust box, there is a gap between the dust box and the sliding plate, the middle part of the convex cover plate is fixedly connected to the rotating shaft, the vertical length of the rotating shaft is greater than the vertical length of the sliding plate, the outer side of the rotating shaft is rotatably sleeved, and the outer blackboard eraser is movably abutted against the sliding plate.

[0014] Furthermore, the collection assembly includes a sliding box, a limit key and a limit slot; the bottom cross bar and the front side of the right side bar are jointly provided with the limit slot, the limit key is slidably arranged in the limit slot, and the front side of the limit key is fixedly connected to the sliding box. When the sliding box slides to the leftmost side of the limit slot, the top of the sliding box is against the bottom of the dust collection box. At this time, the sliding box keeps the dust collection box and the top cross bar relatively fixed.

[0015] The beneficial effects of the present invention are: 1. The application is combined with the frame assembly and the plate assembly, which can be freely assembled and disassembled, and is simple in structure and convenient to install; meanwhile, through the structure of the adaptive slot, the top sliding slot, the top mounting slot, the bottom sliding slot, the bottom mounting slot and the sliding protrusion, the device can realize different combination structures of whiteboard plus sliding board, sliding board plus blackboard, whiteboard plus sliding board plus blackboard during teaching, and the combination of traditional writing and multimedia teaching; further, the multimedia content interaction function is combined with the blackboard to realize smart teaching.

[0016] 2. When the sliding plate moves, the inner blackboard eraser moves back and forth on the fixed plate to clean the fixed plate, and the linkage is strong; when the sliding plate moves, the inner blackboard eraser cleans the chalk dust generated by the fixed plate, which is always between the fixed plate and the sliding plate, and then slowly falls into the U-shaped frame to automatically clean the fixed plate and collect the chalk dust. The inner blackboard eraser can be replaced by sliding the sliding slot, and the U-shaped frame can be pushed out by sliding out of the sliding slot, so that the chalk dust in the U-shaped frame can be collected manually; in this process, no manual operation is required, so that the user will not inhale dust, and the cleaning process is efficient and environmentally friendly.

[0017] 3. The sliding plate is cleaned by sliding the sliding plate, and the chalk dust after cleaning enters the dust collection box, and the sliding box is used to collect the chalk dust in the dust collection box. The sliding box is cleaned by sliding the sliding box to the limit key and the limit key disengaging. When the outer blackboard eraser needs to be replaced, the sliding box is slid to the sliding box and the dust collection box, and the dust collection box can be slid and removed at this time, so that the outer blackboard eraser can be replaced. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a perspective structural schematic view of the application; Figure 2 is a front view structural schematic view of the application; Figure 3 is a perspective structural schematic view between the top cross bar and the bottom cross bar of the application; Figure 4 is a sectional view structural schematic view between the bottom cross bar and the sliding protrusion of the application; Figure 5 is a side view structural schematic view between the bottom cross bar and the outer blackboard eraser of the application; Figure 6 is a sectional view structural schematic view between the plate assembly and the dust collection assembly of the application; Figure 7 is a perspective structural schematic view between the plate assembly and the dust collection assembly of the application; Figure 8is a top view structural schematic diagram of a dust collection assembly of the present application; Figure 9 is a sectional view structural schematic diagram between the collection assembly and the bottom cross bar of the present application.

[0019] Explanation of reference numerals in the drawings: 11, top cross bar; 12, left side bar; 13, bottom cross bar; 14, right side bar; 15, fitting groove; 16, top sliding groove; 17, top mounting groove; 18, bottom sliding groove; 19, bottom mounting groove; 21, whiteboard; 22, fixed plate; 23, sliding plate; 24, sliding protrusion; 31, fixed rod; 32, sliding seat; 33, inner blackboard eraser; 34, blocking key; 35, sliding groove; 36, blocking groove; 41, dust collection groove; 42, U-shaped frame; 43, electric telescopic rod; 44, compression spring; 45, support seat; 51, dust collection box; 52, convex cover plate; 53, rotating shaft; 54, outer blackboard eraser; 61, sliding box; 62, limiting key; 63, limiting groove. DETAILED DESCRIPTION

[0020] Example 1 Please refer to Figures 1-9 ; A push-pull type environmentally-friendly blackboard, comprising a frame assembly and a board assembly, the board assembly comprising a whiteboard 21, a fixed plate 22 and a sliding plate 23, the whiteboard 21 and the fixed plate 22 being arranged at the back side of the frame assembly through a mounting assembly, the sliding plate 23 being arranged at the front side of the frame assembly, a connecting assembly being arranged between the sliding plate 23 and the fixed plate 22, a dust collection assembly being arranged at the bottom of the frame assembly corresponding to the connecting assembly, a fixing assembly being arranged at the front side of the frame assembly corresponding to the sliding plate 23, the fixing assembly being movably arranged with a collection assembly at the bottom; the connecting assembly and the fixing assembly are respectively used for cleaning the fixed plate 22 and the sliding plate 23, and the dust collection assembly and the collection assembly are both used for collecting chalk dust.

[0021] As a further scheme of the present embodiment, the frame assembly comprises a top cross bar 11, a left side bar 12, a bottom cross bar 13 and a right side bar 14; fitting grooves 15 are formed at both sides of the top cross bar 11 and the bottom cross bar 13, wedge blocks are correspondingly arranged at the end portions of the left side bar 12 close to the top cross bar 11 and the bottom cross bar 13, and wedge blocks are also correspondingly arranged at one side of the right side bar 14 close to the left side bar 12, the wedge blocks and the fitting grooves 15 being movably engaged, and the top cross bar 11, the left side bar 12, the bottom cross bar 13 and the right side bar 14 being combined to form a rectangular frame through the wedge blocks and the fitting grooves 15.

[0022] As a further scheme of the embodiment, a top mounting groove 17 is formed at the bottom rear side of the top cross bar 11, and a bottom mounting groove 19 is correspondingly formed at the top rear side of the bottom cross bar 13; a top sliding groove 16 is formed at the bottom front side of the top cross bar 11, and a bottom sliding groove 18 is formed at the top front side of the bottom cross bar 13; sliding protrusions 24 are fixedly connected to the top and bottom ends of the whiteboard 21, the fixed plate 22 and the sliding plate 23, and the two ends of the whiteboard 21 are slidably fitted into the top mounting groove 17 and the bottom mounting groove 19 through the sliding protrusions 24, and the two ends of the fixed plate 22 are slidably fitted into the top mounting groove 17 and the bottom mounting groove 19 through the sliding protrusions 24; the two ends of the sliding plate 23 are slidably fitted into the top sliding groove 16 and the bottom sliding groove 18 through the sliding protrusions 24.

[0023] In the embodiment, the combination of the frame assembly and the plate assembly can freely assemble and disassemble the device, and the device is simple in structure and convenient to install; the combination of the fitting groove, the top sliding groove, the top mounting groove, the bottom sliding groove, the bottom mounting groove and the sliding protrusion can realize different combination structures of the whiteboard plus the sliding plate (when the sliding plate is at the rightmost side), the sliding plate plus the blackboard (when the sliding plate is at the leftmost side), the whiteboard plus the sliding plate plus the blackboard (when the sliding plate is at the middle), and the combination of the traditional writing and the multimedia teaching; the combination of the multimedia content interaction and the blackboard can further realize the smart teaching.

[0024] Embodiment two: In the embodiment one, the structure design of the automatic blackboard eraser is lacking.

[0025] The connecting assembly comprises a fixed rod 31, a sliding seat 32, an inner blackboard eraser 33, a blocking key 34, a sliding groove 35 and a blocking groove 36; the fixed rod 31 is fixedly installed at the rear side of the sliding plate 23, the sliding seat 32 is slidably connected to the fixed rod 31, the inner blackboard eraser 33 is installed on the side of the sliding seat 32 close to the fixed plate 22, the end of the inner blackboard eraser 33 away from the fixed rod 31 is in abutment with the fixed plate 22, the blocking key 34 is formed through the sliding seat 32 and the inner blackboard eraser 33 in the bottom cross bar 13, and the sliding seat 32 and the inner blackboard eraser 33 are slidably arranged in the blocking key 34.

[0026] When the sliding plate 23 moves, the inner blackboard eraser 33 is driven to reciprocate on the fixed plate 22, so that the fixed plate 22 is cleaned.

[0027] As a further scheme of the embodiment, the dust collecting assembly comprises a dust collecting groove 41, a U-shaped frame 42, an electric telescopic rod 43, a compression spring 44 and a support seat 45; the bottom cross rod 13 is provided with the dust collecting groove 41 corresponding to the connecting assembly, the U-shaped frame 42 is slidably arranged in the dust collecting groove 41, one end of the U-shaped frame 42 close to the right side rod 14 abuts against the sliding groove 35, the electric telescopic rod 43 is connected to the end of the U-shaped frame 42 away from the right side rod 14, the support seat 45 is mounted on the sidewall of the dust collecting groove 41 away from the right side rod 14 and connected to the electric telescopic rod 43, the compression spring 44 is further arranged between the support seat 45 and the U-shaped frame 42 and wound outside the electric telescopic rod 43, the compression spring 44 keeps the electric telescopic rod 43 close to the support seat 45, and the horizontal length of the U-shaped frame 42 is greater than the horizontal length of the fixed plate 22 In the embodiment, when the sliding plate 23 moves, the inner blackboard eraser 33 cleans the chalk dust generated by the fixed plate 22 and always stays between the fixed plate 22 and the sliding plate 23, and then slowly falls into the U-shaped frame 42, so that automatic cleaning of the fixed plate 22 and automatic collection of chalk dust are realized, and in this process, manual operation is not required, so that the user will not inhale dust, and the cleaning process is efficient and environmentally friendly.

[0028] As a further scheme of the embodiment, the right side rod 14 is provided with a blocking groove 36 corresponding to the dust collecting groove 41, the sliding groove 35 is slidably arranged in the blocking groove 36, and one end of the sliding groove 35 extending into the frame assembly abuts against the end of the U-shaped frame 42 away from the support seat 45; in a natural state, the other end of the sliding groove 35 extending out of the right side rod 14 abuts against the bottom end of the inner blackboard eraser 33, and at this time, the sliding groove 35 blocks the sliding seat 32 and the inner blackboard eraser 33 from sliding to the bottom of the bottom cross rod 13 through the blocking key 34; when the inner blackboard eraser 33 is replaced, the end of the sliding groove 35 is moved to the inside of the right side rod 14, at this time, the blocking key 34 is communicated, and the sliding seat 32 and the inner blackboard eraser 33 slide out of the inside of the plate assembly and the frame assembly through the blocking key 34; when the U-shaped frame 42 is cleaned, the sliding groove 35 is moved to slide out of the right side rod 14, at this time, the dust collecting groove 41 is communicated with the blocking groove 36, the electric telescopic rod 43 drives the U-shaped frame 42 to slide away from the support seat 45, and the U-shaped frame 42 extends out of the right side rod 14.

[0029] In the embodiment, after a course ends, the inner blackboard eraser 33 can be replaced by sliding the sliding groove 35, and the U-shaped frame 42 can be pushed out by sliding the sliding groove 35, at this time, the chalk dust in the U-shaped frame 42 can be collected manually.

[0030] Embodiment three, In the embodiments one and two, the structure design lacks a fixing assembly.

[0031] Wherein, the fixing assembly includes a dust collecting box 51, a convex cover plate 52, a rotating shaft 53 and an outer blackboard eraser 54; the convex cover plate 52 is slidably arranged on the front side of the top cross bar 11, the dust collecting box 51 is fixedly connected to the convex cover plate 52, there is a gap between the dust collecting box 51 and the sliding plate 23, the rotating shaft 53 is fixedly connected to the middle part of the convex cover plate 52, the vertical length of the rotating shaft 53 is greater than the vertical length of the sliding plate 23, the outer blackboard eraser 54 is rotatably sleeved to the outer side of the rotating shaft 53, and the outer blackboard eraser 54 is movably abutted against the sliding plate 23.

[0032] Therefore, after the top cross bar 11 and the convex cover plate 52 are relatively fixed, the outer blackboard eraser 54 is movably abutted against the sliding plate 23, at this time, the sliding sliding plate 23 realizes cleaning of the sliding plate 23, and the chalk dust after cleaning enters the inside of the dust collecting box 51.

[0033] As a further scheme of the embodiment, the collecting assembly includes a sliding box 61, a limiting key 62 and a limiting slot 63; the limiting slot 63 is formed on the front side of the bottom cross bar 13 and the right side bar 14, the limiting key 62 is slidably arranged in the limiting slot 63, the sliding box 61 is fixedly connected to the front side of the limiting key 62, when the sliding box 61 slides to the leftmost side of the limiting slot 63, the top of the sliding box 61 abuts against the bottom of the dust collecting box 51, at this time, the sliding box 61 keeps the dust collecting box 51 relatively fixed with the top cross bar 11.

[0034] In the embodiment, the sliding box 61 is used for collecting the chalk dust in the dust collecting box 51, sliding the sliding box 61 to the limiting key 62 and the limiting key 62 to be disengaged can realize cleaning of the sliding box 61, and when the outer blackboard eraser 54 needs to be replaced, sliding the sliding box 61 to the dust collecting box 51 to be disengaged can realize removal of the dust collecting box 51, and replacement of the outer blackboard eraser 54.

Claims

1. A push-pull environmentally friendly blackboard, characterized by: The utility model comprises a frame assembly and a plate assembly, wherein the plate assembly comprises a whiteboard, a fixed plate and a sliding plate, wherein the whiteboard and the fixed plate are arranged on the rear side of the frame assembly through an installation assembly, the sliding plate is slidably arranged on the front side of the frame assembly, a connecting assembly is arranged between the sliding plate and the fixed plate, a dust collecting assembly is arranged on the bottom of the frame assembly corresponding to the connecting assembly, a fixing assembly is arranged on the front side of the frame assembly corresponding to the sliding plate, and the collecting assembly is movably arranged on the bottom of the fixing assembly; the connecting assembly and the fixing assembly are respectively used for cleaning the fixed plate and the sliding plate, and the dust collecting assembly and the collecting assembly are both used for collecting chalk dust.

2. The push-pull environmentally friendly blackboard according to claim 1, characterized in that: The frame assembly includes a top cross bar, a left side bar, a bottom cross bar and a right side bar; adapter grooves are provided on both sides of the top cross bar and the bottom cross bar, wedge blocks are correspondingly provided on the ends of the left side bar close to the top cross bar and the bottom cross bar, and a wedge block is also correspondingly provided on the side of the right side bar close to the left side bar, and the wedge blocks are movably engaged with the adapter grooves. The top cross bar, the left side bar, the bottom cross bar and the right side bar are combined through the wedge blocks and the adapter grooves to form a rectangular frame.

3. The push-pull environmentally friendly blackboard according to claim 2, characterized in that: The top mounting groove is provided on the rear side of the bottom of the top cross bar, and the bottom mounting groove is correspondingly provided on the rear side of the top of the bottom cross bar; the top slide groove is provided on the front side of the bottom of the top cross bar, and the bottom slide groove is provided on the front side of the top of the bottom cross bar; the top and bottom ends of the whiteboard, fixed plate and sliding plate are fixedly connected with sliding protrusions, and the two ends of the whiteboard are slidably adapted to the top mounting groove and the bottom mounting groove through the sliding protrusions, and the two ends of the fixed plate are slidably adapted to the top mounting groove and the bottom mounting groove through the sliding protrusions; the two ends of the sliding plate are slidably adapted to the top slide groove and the bottom slide groove through the sliding protrusions.

4. The push-pull environmentally friendly blackboard according to claim 3, characterized in that: The connecting assembly includes a fixed rod, a sliding seat, an inner blackboard eraser, a blocking key, a sliding slot and a blocking slot; A fixing rod is fixedly installed on the rear side of the sliding plate, and the fixing rod is slidably connected to the sliding seat. The inner blackboard eraser is installed on the side of the sliding seat close to the fixed plate, and the end of the inner blackboard eraser away from the fixing rod is in contact with the fixed plate. A blocking key is provided on the bottom cross bar corresponding to the sliding seat and the inner blackboard eraser, and the sliding seat and the inner blackboard eraser are slidably arranged inside the blocking key.

5. The push-pull environmentally friendly blackboard according to claim 4, characterized in that: The dust collection assembly includes a dust collection trough, a U-shaped frame, an electric telescopic rod, a compression spring and a support seat; The bottom cross bar is provided with a dust collecting groove corresponding to the connecting assembly, and the U-shaped frame is slidably arranged in the dust collecting groove, and one end of the U-shaped frame close to the right rod abuts against the sliding groove, and the end of the U-shaped frame away from the right rod is connected to the electric telescopic rod, and the side wall of the dust collecting groove away from the right rod is installed with the support seat, and the support seat is connected to the electric telescopic rod. The compression spring is also provided between the support seat and the U-shaped frame, and the compression spring is wound around the outside of the electric telescopic rod, and the compression spring keeps the electric telescopic rod close to the support seat; the horizontal length of the U-shaped frame is greater than the horizontal length of the fixed plate.

6. The push-pull environmentally friendly blackboard according to claim 5, characterized in that: When cleaning the U-shaped frame, move the sliding groove to slide out of the right rod, and the dust collecting trough is connected with the blocking groove, and the electric telescopic rod drives the U-shaped frame to slide away from the support seat, and the U-shaped frame extends out of the right rod.

7. The push-pull environmentally friendly blackboard according to claim 4, characterized in that: The fixed assembly includes a dust box, a convex cover plate, a rotating shaft and an external blackboard eraser; The convex cover plate is slidably provided on the front side of the top cross bar, and the convex cover plate is fixedly connected to the dust collection box. There is a gap between the dust collection box and the sliding plate. The middle part of the convex cover plate is fixedly connected to the rotating shaft, the vertical length of the rotating shaft is greater than the vertical length of the sliding plate, and the outer blackboard eraser is rotatably sleeved on the outer side of the rotating shaft, and the outer blackboard eraser is movably abutted against the sliding plate.

8. The push-pull environmentally friendly blackboard according to claim 7, characterized in that: The collecting assembly includes a sliding box, a limit key and a limit slot; The bottom cross bar and the front side of the right side bar are jointly provided with the limit groove, the limit key is slidably provided in the limit groove, and the front side of the limit key is fixedly connected to the sliding box. When the sliding box slides to the leftmost side of the limit groove, the top of the sliding box is against the bottom of the dust box. At this time, the sliding box keeps the dust box and the top cross bar relatively fixed.

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