Negative pressure dustproof blackboard eraser
By miniaturizing the Roots blower and combining it with a stepped wiping section and a dust suction port design, the problem of insufficient dust suction capacity of existing dust-collecting blackboard erasers has been solved, achieving efficient dust removal, protecting the health of teachers and students, and extending the life of the blower.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HUAINAN NORMAL UNIV
- Filing Date
- 2025-05-07
- Publication Date
- 2026-04-17
AI Technical Summary
Existing dust-collecting blackboard erasers have long air ducts, resulting in a small negative pressure difference, generally poor dust collection ability, and dust easily accumulates on the fan blades, affecting the dust collection effect and the lifespan of the fan.
The Roots blower is miniaturized and applied to blackboard eraser dust collection. It combines a stepped wiping section and a dust collection hole design, uses a negative pressure chamber and a dust collection box to collect dust, and uses a miniature Roots blower and a DC brushless motor to adjust the suction power to prevent dust from escaping.
It achieves efficient dust removal, protects the health of teachers and students, extends the life of the fan, has a compact structure, is easy to use, and is suitable for widespread application.
Smart Images
Figure CN224130769U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of teaching aids technology, and in particular to a negative pressure dustproof blackboard eraser. Background Technology
[0002] In teaching, teachers mostly need to use chalk to write on the blackboard. When erasing the blackboard, chalk dust will be released into the air, which is to some extent detrimental to the health of both teachers and students.
[0003] Existing technologies also offer dust-collecting blackboard erasers with different structures, but most of the current dust-collecting blackboard erasers use fans to adsorb dust. Considering the structural design, the air duct is usually long, resulting in a small negative pressure difference and generally poor dust collection ability. At the same time, when the fan is collecting dust, dust tends to accumulate on the fan blades, affecting the dust collection effect and the lifespan of the fan. Utility Model Content
[0004] To address the technical shortcomings of existing dust-collecting blackboard erasers, this utility model provides a negative pressure dustproof blackboard eraser that miniaturizes the Roots blower and applies it to blackboard eraser dust collection. The overall structure is compact and the dust collection effect is good.
[0005] A negative pressure dustproof blackboard eraser includes a housing and an wiping section disposed at the bottom of the housing. During use, the wiping section is parallel to the blackboard.
[0006] The contact surface between the wiping part and the blackboard is embedded and stepped, with several dust suction holes on it, and brush bristles densely distributed between the dust suction holes;
[0007] The box contains a negative pressure chamber. A negative pressure generating mechanism is provided on one side of the negative pressure chamber, and a dust collection box is sealed and slidably inserted on the other side. The dust collection box is connected to the negative pressure generating mechanism. An exhaust port connected to the negative pressure generating mechanism is provided on the front side of the box.
[0008] The dust collection box has dust inlet holes on both sides, a filter screen on the side connected to the negative pressure generating mechanism, and a dust discharge opening at the top. During operation, the dust discharge opening is closed.
[0009] Furthermore, the negative pressure cavity is provided with multiple dust collection box limiting posts, which are located on both sides of the dust collection box.
[0010] Furthermore, the dust collection box is provided with a handle on the side away from the negative pressure generating mechanism for easy pulling.
[0011] Furthermore, the negative pressure generating mechanism includes a miniature Roots blower installed inside the negative pressure chamber.
[0012] Furthermore, the miniature Roots blower includes a housing and at least two cooperating Roots rotors located inside it. The Roots rotors are respectively fixed on their respective rotating shafts, and synchronous gears are also fixed on the rotating shafts respectively. The synchronous gears mesh with each other, and a drive motor is fixed on one of the rotating shafts.
[0013] Furthermore, the drive motor protrudes from the housing and is covered by a heat dissipation shell.
[0014] Furthermore, a handle for gripping is provided on the top of the box body. The handle is made of heat-insulating material and is fixedly connected to the heat dissipation shell.
[0015] Furthermore, a power supply battery is installed inside the grip, and a battery charging port is provided on the side of the grip away from the heat dissipation shell.
[0016] Furthermore, the front end of the grip is provided with a control board electrically connected to the drive motor and the power supply battery, and the grip is provided with a control switch electrically connected to the control board.
[0017] The beneficial effects of this utility model are:
[0018] 1. The negative pressure generated inside the box by the Roots blower draws the chalk dust (i.e., chalk dust) raised when wiping the blackboard into the negative pressure chamber. Combined with the strong suction of the Roots blower, it can effectively prevent the dust from escaping. The drive motor can be an adjustable speed DC brushless motor. The suction of the negative pressure generating mechanism can be adjusted according to the amount of chalk dust to ensure a good dust collection effect.
[0019] 2. The dust collection box design effectively prevents dust from entering the Roots blower, ensuring its stable operation. It also collects and stores dust for convenient subsequent processing and ease of use. Furthermore, the replaceable dust filter effectively collects dust and prevents it from entering the negative pressure device and causing the Roots pump to seize.
[0020] 3. The handle has a built-in rechargeable battery to extend the blackboard eraser's battery life.
[0021] In summary, this utility model has a reasonable design and simple structure. It can absorb dust when wiping the blackboard, preventing dust from escaping, protecting the health of teachers and students, and is easy to clean. It is stable in operation and suitable for widespread use. Attached Figure Description
[0022] Figure 1 A three-dimensional structural diagram of a negative pressure dustproof blackboard eraser from the front view.
[0023] Figure 2 A three-dimensional structural diagram of a negative pressure dustproof blackboard eraser from the rear view.
[0024] Figure 3A three-dimensional structural diagram of the bottom of a negative pressure dustproof blackboard eraser;
[0025] Figure 4 for Figure 3 Enlarged schematic diagram of the structure at point A in the middle;
[0026] Figure 5 This is a magnified view of a portion of the suction hole;
[0027] Figure 6 A three-dimensional schematic diagram of the internal structure of the negative pressure chamber;
[0028] Figure 7 A schematic diagram of a miniature Roots blower, a dust collection box, and their connections;
[0029] Figure 8 This is a 3D structural diagram of the dustbin.
[0030] Figure 9 This is a cross-sectional view of the internal structure of a negative pressure dustproof blackboard eraser.
[0031] Figure 10 This is a schematic diagram of the internal structure of the negative pressure chamber.
[0032] In the diagram: 1. Box body, 11. Negative pressure chamber, 12. Exhaust port, 2. Wiping part, 31. Brush bristles, 32. Dust suction hole, 4. Negative pressure generating mechanism, 41. Roots blower, 41. Synchronous gear, 412. Roots rotor, 413. Drive motor, 414. Heat dissipation shell, 415. Control board, 42. Power supply battery, 43. Charging port, 44. Control switch, 45. Dust collection box, 51. Dust inlet, 52. Filter screen, 53. Dust outlet, 54. Handle, 55. Limiting post, 6. Grip. Detailed Implementation
[0033] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.
[0034] A negative pressure dustproof blackboard eraser, such as Figure 1-3 As shown, the device includes a housing 1 and an wiping section 2 located at the bottom of the housing 1. Similar to a conventional blackboard eraser, the wiping section 2 is parallel to the blackboard during use.
[0035] If the wiping part 2 is in close contact with the blackboard, it will greatly reduce the chalk dust collection effect. Therefore, the contact surface between the wiping part 2 and the blackboard is embedded and stepped (see...). Figure 4 This creates a dust collection space between the blackboard and the wiping section 2. The wiping section 2 is provided with several dust suction holes 32 (see...). Figure 5 The dust suction holes 32 are densely covered with brush filaments 31, which can be made of materials such as nylon blended fibers and modified polyester fibers.
[0036] When the blackboard is erased by hand, the bristles 31 wipe the chalk marks, causing chalk dust to rise and be confined within the dust collection space between the blackboard and the erasing part 2. At the same time, the negative pressure generating mechanism 4 is activated, drawing the chalk dust in the dust collection space into the box 1 through the dust suction hole 32, thereby preventing the chalk dust from being scattered into the air.
[0037] The box body 1 contains a negative pressure chamber 11. A negative pressure generating mechanism 4 is located on one side of the negative pressure chamber 11, and a dust collection box 5 is sealed and slidably (vertically) inserted into the other side. (See attached image.) Figure 6 , Figure 7 The dust collection box 5 is connected to the negative pressure generating mechanism 4, and an exhaust port 12 connected to the negative pressure generating mechanism 4 is provided on the front side of the box body 1. Dust inlets 51 are densely distributed on both sides of the dust collection box 5, a filter screen 52 is provided on the side connected to the negative pressure generating mechanism 4, and a dust outlet 53 is provided at the top. (See also...) Figure 8 .
[0038] After the dust collection box 5 is installed in place, it is fixed relative to the top of the box body 1. During operation, the dust outlet 53 is flush against the top wall of the box body 1, remaining closed. After the blackboard erasing is completed, the negative pressure generating mechanism 4 remains open until the chalk dust is removed and poured out. The dust collection box 5 can be fixed to the box body using electromagnetic attraction; it is attracted and fixed when energized and detached when de-energized. It is linked with the negative pressure generating mechanism 4, making operation convenient and quick.
[0039] Chalk dust is drawn into the dust collection box 1 through the suction port 32 and then enters the negative pressure chamber 11. The negative pressure generating mechanism 4 is located at the front of the negative pressure chamber 11 and is housed within a sealed casing. Under the action of the negative pressure generating mechanism, air containing chalk dust is drawn into the dust collection box 5 through the dust inlet 51, then passes through the filter screen 52, enters the negative pressure generating mechanism, and finally is discharged through the exhaust port 12. Due to the interception by the filter screen 52, chalk dust will not enter the negative pressure generating mechanism.
[0040] To limit the movement of the dust collection box 5 during insertion and withdrawal, the negative pressure chamber 11 is provided with multiple dust collection box limiting posts 55, which are located on both sides of the dust collection box 5. (See attached image.) Figure 6 Meanwhile, to facilitate pulling out, the dust collection box 5 is provided with a handle 54 on the side away from the negative pressure generating mechanism 4.
[0041] To save space and prevent chalk dust from accumulating on the fan blades, the negative pressure generating mechanism 4 includes a miniature Roots blower 41 installed within a negative pressure chamber 11. The miniature Roots blower 41 includes a housing and at least two cooperating Roots rotors 413 located inside it. The Roots rotors 413 are respectively fixed to their respective rotating shafts 411, and synchronous gears 412 are also fixed to the rotating shafts 411. The synchronous gears 412 mesh with each other. A drive motor 414 is fixed to one of the rotating shafts 411. Figure 9 , Figure 10 .
[0042] certainly, Figure 9 The diagram shows two Roots rotors 413. Three could also be used, but considering manufacturing costs, two Roots rotors are sufficient for the blackboard eraser application. The miniature Roots blower 41 is driven by a brushless DC motor 414, which drives the Roots rotors 413 at high speed.
[0043] Before the protruding parts (tooth tips) of the two rotors contact the cylinder wall, a closed "V"-shaped intake chamber is formed. As the rotors rotate counterclockwise / clockwise (assuming one rotor rotates counterclockwise, the other clockwise), the volume of the intake chamber gradually expands, the internal pressure decreases, and gas is drawn into the chamber through the intake port. As the rotors rotate, the intake chamber gradually shrinks, and the gas is sealed in the enclosed space between the rotor and the cylinder wall. As the rotors continue to rotate, the volume of the enclosed chamber decreases, the gas is compressed, and the pressure gradually increases (the final pressure depends on the exhaust port resistance). When the enclosed chamber moves to the vicinity of the exhaust port, its volume reaches its minimum. When the enclosed chamber connects with the exhaust port, the high-pressure gas is instantly discharged and enters the exhaust pipe. The exhaust process is accompanied by pressure pulsations (because the rotors rotate continuously, one exhaust cycle is completed per revolution).
[0044] For structural design considerations, the drive motor 414 protrudes from the housing 1, see [reference]. Figure 1 It is covered with a heat dissipation shell 415, which can be made of a material with good thermal conductivity, and can also be provided with ventilation and heat dissipation holes (not shown).
[0045] For ease of use, a handle 6 for gripping is provided on the top of the housing 1. The handle 6 is made of heat-insulating material and is fixedly connected to the heat dissipation shell 415. A power supply battery 43 is installed inside the handle 6 (see...). Figure 9 The handle 6 has a battery charging port 44 on the side away from the heat dissipation housing 415 (see [link]). Figure 6 ).
[0046] The power supply battery 43 is housed within the handle 6, maximizing space efficiency. Furthermore, the drive motor 414 is located at the front of the handle 6, facilitating power supply and demonstrating ingenious structural design. A control board 42, electrically connected to the drive motor 414 and the power supply battery 43, is located at the front of the handle 6. A control switch 45, electrically connected to the control board 42, is also located on the handle 6. The control switch 45 controls the activation of the negative pressure generating mechanism 4 and the suction between the dust collection box 5 and the top wall of the box body 1. Simultaneously, a speed switch can be set to control the speed of the drive motor, thereby adjusting the suction power of the negative pressure generating mechanism 4 according to the amount of chalk dust, ensuring effective dust collection.
[0047] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.
Claims
1. A negative pressure dustproof blackboard eraser, comprising a housing (1) and an wiping part (2) disposed at the bottom of the housing (1), wherein during use, the wiping part (2) is parallel to the blackboard, characterized in that: The wiping part (2) is embedded in the contact surface with the blackboard and is stepped. It is provided with a number of dust suction holes (32) and brush bristles (31) are densely distributed between the dust suction holes (32). The box body (1) contains a negative pressure chamber (11). A negative pressure generating mechanism (4) is provided on one side of the negative pressure chamber (11), and a dust collection box (5) is sealed and slidably inserted on the other side. The dust collection box (5) is connected to the negative pressure generating mechanism (4). An exhaust port (12) connected to the negative pressure generating mechanism (4) is provided on the front side of the box body (1). The dust collection box (5) has dust inlet holes (51) on both sides, a filter screen (52) is provided on the side connected to the negative pressure generating mechanism (4), and a dust discharge opening (53) is provided at the top. During operation, the dust discharge opening (53) is closed.
2. The dustproof blackboard eraser of negative pressure according to claim 1, characterized in that, The negative pressure cavity (11) is provided with a plurality of dust collection box limiting posts (55), which are located on both sides of the dust collection box (5).
3. The dustproof blackboard eraser of negative pressure according to claim 1, characterized in that, The dust collection box (5) is provided with a handle (54) on the side away from the negative pressure generating mechanism (4) for easy pulling.
4. The dust-repelling blackboard eraser according to any one of claims 1 to 3, characterized in that The negative pressure generating mechanism (4) includes a miniature Roots blower (41) installed inside the negative pressure cavity (11).
5. The dust-repelling blackboard eraser of claim 4, wherein The miniature Roots blower (41) includes a housing and at least two cooperating Roots rotors (413) located inside it. The Roots rotors (413) are respectively fixed on their respective rotating shafts (411). Synchronous gears (412) are also fixed on the rotating shafts (411). The synchronous gears (412) mesh with each other. A drive motor (414) is fixed on one of the rotating shafts (411).
6. The dustproof blackboard eraser of negative pressure according to claim 5, characterized in that, The drive motor (414) protrudes from the housing (1) and is covered by a heat dissipation shell (415).
7. The dustproof blackboard eraser of negative pressure according to claim 6, characterized in that, The box body (1) is provided with a handle (6) for holding.
8. The dustproof blackboard eraser of negative pressure according to claim 7, characterized in that, The handle (6) is made of heat-insulating material and is fixedly connected to the heat dissipation shell (415).
9. The dustproof blackboard eraser of claim 7, wherein, A power supply battery (43) is provided inside the handle (6), and a battery charging port (44) is provided on the side of the handle (6) away from the heat dissipation shell (415).
10. A dust-repelling blackboard eraser of negative pressure according to claim 7, characterized in that, The front end of the handle (6) is provided with a control board (42) electrically connected to the drive motor (414) and the power supply battery (43), and the handle (6) is provided with a control switch (45) electrically connected to the control board (42).