Blackboard cleaning device

Abstract

The present invention discloses a blackboard dust removal device, comprising a top high-pressure flow channel, a bottom collector, sidewall flow channels, and an air compressor. The top high-pressure flow channel and the bottom collector are respectively arranged at the top and bottom of the blackboard, the sidewall flow channels are respectively arranged on both sides of the blackboard, and the air outlet of the air compressor is connected to the top high-pressure flow channel. The present invention achieves a dust removal effect around the blackboard.

Description

Technical Field

[0001] The present invention particularly relates to a blackboard cleaning device. Background Art

[0002] When the blackboard is wiped during normal breaks, dust often flies everywhere. Over time, teachers and students in the front row who are closer to the blackboard are more likely to inhale excessive dust, which has a certain impact on their health. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a blackboard cleaning device to achieve the dust removal effect around the blackboard in view of the above-mentioned defects in the prior art.

[0004] The technical solution adopted by the present invention to solve the above technical problems is:

[0005] A blackboard cleaning device includes a top high-pressure flow channel, a bottom collector, a side wall flow channel and a compressor. The top high-pressure flow channel and the bottom collector are respectively arranged at the top and bottom of the blackboard, the side wall flow channels are respectively arranged on both sides of the blackboard, and the air outlet end of the compressor is connected to the top high-pressure flow channel.

[0006] According to the above technical solution, the air outlet of the top high-pressure flow channel is provided with a flow channel opening and closing plate assembly, which is connected to a driving device. The driving device drives the flow channel opening and closing plate assembly to move back and forth, thereby opening and closing the air outlet of the top high-pressure flow channel.

[0007] According to the above technical solution, the driving device includes a transmission mechanism and a motor, and the motor is connected to the flow channel opening and closing plate assembly through the transmission mechanism.

[0008] According to the above technical solution, the transmission mechanism includes a transmission shaft and a cam, the transmission shaft is arranged horizontally, the cam is sleeved on the transmission shaft, and the motor is connected to the transmission shaft;

[0009] The cam is in contact with the flow channel opening and closing plate assembly, and the flow channel opening and closing plate assembly is connected to a return spring. The return spring ensures that the flow channel opening and closing plate assembly is always in contact with the cam. The motor drives the cam to rotate through the transmission shaft, and the cam drives the flow channel opening and closing plate assembly to move back and forth, thereby opening or closing the air outlet of the top high-pressure flow channel.

[0010] According to the above technical solution, the blackboard is divided into multiple panels in the length direction;

[0011] The top high-pressure flow channel is provided with a plurality of air outlets distributed along the length direction of the blackboard, and each air outlet is arranged one-to-one corresponding to each blackboard surface. The flow channel opening and closing plate assembly includes a plurality of flow channel opening and closing plates arranged in sequence along the length direction of the blackboard, and each flow channel opening and closing plate is respectively arranged in a corresponding air outlet;

[0012] The number of cams is consistent with the number of flow channel opening and closing plates, and they are arranged one by one. Multiple cams are arranged on the transmission shaft in sequence along the length direction of the blackboard. Each flow channel opening and closing plate is in contact and connected with the corresponding cam, and each flow channel opening and closing plate is connected with a return spring.

[0013] According to the above technical solution, the blackboard cleaning device also includes a blackboard eraser, a controller and a sensor. A locator is provided on the blackboard eraser, and an arc-shaped guide plate is provided on the top of the blackboard eraser. The arc-shaped guide plate guides the airflow blowing from above to one side of the blackboard eraser; the locator is arranged on one side of the blackboard eraser, and the tail end of the arc-shaped guide plate is arranged along the other side of the blackboard eraser. The arc-shaped guide plate guides the upper airflow to the side of the blackboard eraser, so that the airflow continues to move downward, and the arc-shaped surface of the arc-shaped guide plate protrudes outward. The controller is connected to the sensor and the motor respectively. The sensor is arranged on one side of the blackboard for detecting the locator on the blackboard eraser. When the sensor detects that the locator on the blackboard eraser is on the corresponding blackboard page, the air outlet corresponding to the page is closed, and the air outlets corresponding to the remaining pages are all opened.

[0014] According to the above technical solution, the closed curves on each cam acting on the corresponding flow channel opening and closing plate are distributed on the transmission shaft at staggered angles.

[0015] According to the above technical solution, the cams arranged at the outermost ends of the transmission shaft are end cams, and the cams located between the end cams on both sides are middle cams;

[0016] The outer edge curve of the middle cam is a middle cam conventional opening and closing curve, a middle cam speed-increasing curve, a middle cam closing curve and a middle cam speed-increasing curve connected in sequence end to end;

[0017] The end cam outer edge curve is the end cam conventional opening and closing curve, the end cam closing curve and the end cam speed-increasing curve connected in sequence end to end;

[0018] The speed-increasing curve, conventional opening and closing curve and closing curve of each cam and the distance between the contact point of the corresponding flow channel opening and closing plate and the transmission shaft increase in sequence;

[0019] When the regular opening and closing curve of the cam contacts the flow channel opening and closing plate, the flow channel opening and closing plate is pushed outward, and the flow channel opening and closing plate pushes outward to open the corresponding top high-pressure flow channel section. When the closing curve of the cam contacts the flow channel opening and closing plate, the flow channel opening and closing plate retracts, and the retracted flow channel opening and closing plate closes the corresponding top high-pressure flow channel section.

[0020] When a certain cam contacts the corresponding flow channel opening and closing plate through a closed curve, its adjacent cam contacts the corresponding flow channel opening and closing plate through a speed-increasing curve, and the remaining cams contact the corresponding flow channel opening and closing plates through conventional opening and closing curves.

[0021] According to the above technical solution, a slide groove is provided on one side of each flow channel opening and closing plate on the top high-pressure flow channel. The flow channel opening and closing plate is arranged on the slide groove and can move back and forth along the slide groove to open and close the top high-pressure flow channel.

[0022] According to the above technical solution, the upper end of the side wall flow channel is connected to the compressor through the top high-pressure flow channel, the lower end of the side wall flow channel is connected to the bottom collector, and a negative pressure suction hole is provided on the side wall of the side wall flow channel close to the blackboard. An opening and closing plate is provided in the side wall flow channel, and the opening and closing plate is connected to the side wall flow channel through a rotating shaft. The rotating shaft is connected to a rotating transmission mechanism, and the rotating transmission mechanism drives the opening and closing plate to rotate through the rotating shaft to realize the opening or closing of the negative pressure suction hole of the side wall flow channel. The bottom collector is connected to the purified air flow channel, and the purified air flow channel is arranged below the side wall flow channel; the purified air inlet of the purified air flow channel is connected to the bottom collector, and the purified air outlet of the purified air flow channel is connected to the outside, and a filter element is provided in the purified air flow channel.

[0023] According to the above technical solution, a spring is connected to the rotating shaft or the opening and closing plate; the rotary transmission mechanism includes a No. 1 piston, an inner compression piston cylinder, and a No. 2 piston, the No. 1 piston and the No. 2 piston being respectively arranged at the two ends of the inner compression piston cylinder, the No. 1 piston is connected to the driving device, and the spring keeps the No. 2 piston in contact with the opening and closing plate; the driving device drives the No. 1 piston to move back and forth along the inner compression piston cylinder, thereby driving the No. 2 piston to move back and forth along the inner compression piston cylinder, and the No. 2 piston pushes the opening and closing plate to rotate around the rotating shaft;

[0024] There is a protrusion at the bottom of the flow channel opening and closing plate, and an inclined step is provided on the outer ring of piston No. 1. The protrusion fits with the inclined step. During the back and forth movement of the flow channel opening and closing plate, the protrusion squeezes piston No. 1 through the inclined step to move back and forth along the inner compression piston cylinder. When the flow channel opening and closing plate adjacent to the side wall flow channel closes the corresponding top high-pressure flow channel outlet, the negative pressure suction hole of the side wall flow channel is opened.

[0025] The present invention has the following beneficial effects:

[0026] 1. The present invention continuously ejects air from the top high-pressure flow channel to the bottom collector, forming a high-speed airflow in front of the blackboard. By utilizing the Coanda effect and the Bernoulli principle, the dust suspended around the blackboard is curled and sucked into the interior of the device through the high-speed flow of a small amount of airflow, thereby achieving a dust removal effect around the blackboard.

[0027] 2. The closed curves of the cams acting on the corresponding flow channel opening and closing plates are staggered in angle distribution, so that the opening and closing plates of each flow channel are staggered to form a pressure-regulated adsorption system. When air is temporarily supplied to a local black plate, the dust removal effect can also be achieved through negative pressure suction and curling on the left and right sides. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic structural diagram of a blackboard cleaning device according to an embodiment of the present invention;

[0029] Figure 2 Schematic diagram of the structure of the side wall flow channel in an embodiment of the present invention;

[0030] Figure 3 2 is a schematic structural diagram of the top high-pressure flow channel in an embodiment of the present invention;

[0031] Figure 4 2 is a schematic structural diagram of the middle cam in an embodiment of the present invention;

[0032] Figure 5 Schematic diagram of the structure of the transmission mechanism and the rotation transmission mechanism in an embodiment of the present invention;

[0033] Figure 6 is a structural schematic diagram of a transmission mechanism in an embodiment of the present invention;

[0034] Figure 7 2 is a schematic structural diagram of an end cam in an embodiment of the present invention;

[0035] Figure 8 Schematic diagram of the airflow direction in front of the blackboard when the blackboard eraser is working at the junction of two adjacent pages in an embodiment of the present invention;

[0036] Figure 9 Schematic diagram of the airflow direction in front of the blackboard when the blackboard eraser is working in the middle of a blackboard page in an embodiment of the present invention;

[0037] Figure 10 1 is a schematic structural diagram of a blackboard eraser according to an embodiment of the present invention;

[0038] In the figure, 1- compressor, 2- blackboard, 3- bottom collector, 4- filter screen, 5- formaldehyde catalytic filter, 6- side wall flow channel, 7- opening and closing plate, 8- spring spring, 9- stepping motor, 10- top airflow housing, 11- top high-pressure flow channel, 12- flow channel opening and closing plate, 13- middle cam, 14- No. 2 piston, 15- piston cylinder, 16- No. 1 piston, 17- return spring, 18- small roller, 19- transmission shaft, 20- end cam, 21- blackboard eraser.

[0039] 601-piston cylinder mounting slot, 602-blackboard mounting slot, 603-negative pressure suction hole, 604-negative pressure suction flow channel, 605-opening and closing plate mounting seat, 606-suction outlet, 607-purified gas inlet, 608-purified gas flow channel, 609-purified gas outlet;

[0040] 1101-drive shaft mounting slot, 1102-piston cylinder mounting hole, 1103-return spring mounting hole, 1104-baffle, 1105-outlet flow channel, 1106-chute;

[0041] 1301- normal opening and closing curve of the middle cam, 1302- speed-increasing curve of the middle cam, 1303- closing curve of the middle cam;

[0042] 2001- normal opening and closing curve of end cam, 2002- closing curve of end cam, 2003- speed increasing curve of end cam;

[0043] 2101-Locator, 2102-Blackboard eraser body, 2103-Curved guide plate. DETAILED DESCRIPTION

[0044] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0045] Reference Figures 1 to 10 As shown, a blackboard cleaning device in an embodiment of the present invention includes a top high-pressure flow channel 11, a bottom collector 3, a side wall flow channel 6 and a compressor 1. The top high-pressure flow channel 11 and the bottom collector 3 are respectively arranged at the top and bottom of the blackboard 2, the side wall flow channel 6 is respectively arranged on both sides of the blackboard 2, and the air outlet end of the compressor 1 is connected to the top high-pressure flow channel 11.

[0046] Furthermore, the air outlet of the top high-pressure flow channel 11 is provided with a flow channel opening and closing plate assembly, which is connected to a driving device. The driving device drives the flow channel opening and closing plate assembly to move back and forth, thereby opening and closing the air outlet of the top high-pressure flow channel 11.

[0047] A baffle is provided above the flow channel opening and closing plate assembly in the top high-pressure flow channel 11, and a baffle is provided above the inner wall of the top high-pressure flow channel 11 on the closed side of the flow channel opening and closing plate. The baffle 1104 makes the air outlet closed more tightly.

[0048] Furthermore, the top high-pressure flow channel 11 is covered with a top airflow shell 10 .

[0049] Furthermore, the driving device includes a transmission mechanism and a stepping motor 9, and the stepping motor 9 is connected to the flow channel opening and closing plate assembly through the transmission mechanism.

[0050] Furthermore, the transmission mechanism includes a transmission shaft 19 and a cam. The transmission shaft 19 is arranged horizontally along the length direction of the top high-pressure flow channel 11. The cam is sleeved on the transmission shaft 19. The stepper motor 9 is connected to the transmission shaft 19.

[0051] A small roller 18 is provided on the flow channel opening and closing plate assembly, and the cam is in contact with the small roller 18 on the flow channel opening and closing plate assembly. The flow channel opening and closing plate assembly is connected with a return spring 17. The return spring 17 ensures that the small roller 18 on the flow channel opening and closing plate assembly is always in contact with the cam. The stepper motor 9 drives the cam to rotate through the transmission shaft 19, and the cam drives the flow channel opening and closing plate assembly to move back and forth, thereby realizing the opening or closing of the air outlet of the top high-pressure flow channel 11.

[0052] Furthermore, both ends of the return spring 17 are connected to the flow channel opening and closing plate assembly and the top high-pressure flow channel 11 respectively.

[0053] Furthermore, the blackboard 2 is evenly divided into multiple panels in the length direction;

[0054] The top high-pressure flow channel 11 has multiple air outlets distributed along the length direction of the blackboard 2. Each air outlet corresponds to an outlet flow channel. Each air outlet is arranged one-to-one with each blackboard surface. The flow channel opening and closing plate assembly includes multiple flow channel opening and closing plates 12 arranged in sequence along the length direction of the blackboard. Each flow channel opening and closing plate 12 is respectively set in the corresponding air outlet;

[0055] The number of cams is consistent with the number of flow channel opening and closing plates 12, and they are arranged one by one. Multiple cams are arranged on the transmission shaft 19 in sequence along the length direction of the blackboard. Each flow channel opening and closing plate 12 is provided with a small roller 18, which is connected to the corresponding cam through the small roller 18. Each flow channel opening and closing plate 12 is connected with a return spring 17.

[0056] Furthermore, the blackboard cleaning device also includes a blackboard eraser, a controller and a sensor. A locator 2101 is provided on the blackboard eraser 21, and an arc-shaped guide plate 2103 is provided on the top of the blackboard eraser 21. The arc-shaped guide plate 2103 guides the airflow blown from above to one side of the blackboard eraser 21; the locator 2101 is arranged on one side of the blackboard eraser 21, and the tail end of the arc-shaped guide plate 2103 is arranged along the other side of the blackboard eraser 21. The arc-shaped guide plate 2103 guides the upper airflow to the side of the blackboard eraser 21, so that the airflow continues to move downward. The arc-shaped surface of the arc-shaped guide plate 2103 protrudes outward. The controller is connected to the sensor and the motor respectively. The sensor is arranged on one side of the blackboard for detecting the locator 2101 on the blackboard eraser 21. When the sensor detects that the locator 2101 on the blackboard eraser 21 is on the corresponding blackboard page, the air outlet corresponding to the page is closed, and the air outlets corresponding to the other pages are opened.

[0057] The blackboard eraser 21 includes a blackboard eraser body 2102, a positioner 2101 and an arc-shaped guide plate 2103. The positioner 2101 and the arc-shaped guide plate 2103 are respectively arranged on both sides of the blackboard eraser body 2102. The positioner 2101 is arranged on the blackboard eraser body 2102. The upper end of the arc-shaped guide plate 2103 is arranged above the blackboard eraser, and the lower end of the arc-shaped guide plate 2103 is arranged along the side of the blackboard eraser.

[0058] When the blackboard eraser is in the middle of a page on the blackboard, the air outlet of the top high-pressure flow channel 11 corresponding to the page where the blackboard eraser is located is closed, and the air outlet of the top high-pressure flow channel 11 corresponding to the page adjacent to the page is opened, and it is a high-intensity airflow. According to Bernoulli's principle, the gas in front of the page where the blackboard eraser is located will be attracted to the adjacent page. When the page where the blackboard eraser is located is the outermost page, the negative pressure suction hole 603 of the side wall flow channel 6 is opened to suck in the gas in front of the page, such as Figure 9 As shown, the blackboard eraser is on page 2, the air outlet of the top high-pressure flow channel 11 corresponding to page 2 is closed, the air supply is suspended, and the air supply to pages 1 and 3 is accelerated, and the dust gas on page 2 is sucked to pages 1 and 2 on both sides respectively.

[0059] When the blackboard eraser is at the junction of two blackboard pages, Figure 8 As shown, the locator is on one of the layouts, and part of the blackboard eraser is on another adjacent layout. The air outlet of the top high-pressure flow channel 11 corresponding to the layout where the locator is located is closed, and the air outlet corresponding to the adjacent layout is still open. At this time, the arc-shaped guide plate 2103 guides the downward-flowing airflow of the blackboard eraser above the layout downward, preventing the downward-flowing airflow from directly hitting the blackboard eraser body 2102 and splashing onto the human body.

[0060] Furthermore, if the positioning locator is arranged on the left side of the blackboard eraser, the tail end of the arc guide plate 2103 is arranged on the right side of the blackboard eraser; if the locator is arranged on the right side of the blackboard eraser, the tail end of the arc guide plate 2103 is arranged on the left side of the blackboard eraser.

[0061] Furthermore, a return spring mounting hole 1103 and a drive shaft mounting groove 1101 are provided on the wall surface of the top high-pressure flow channel 11, which are used to install the return spring 17 and the drive shaft respectively. Piston cylinder mounting holes 1102 are also provided on both ends of the top high-pressure flow channel 11 for connecting and installing the piston cylinder.

[0062] Furthermore, the closed curves on each cam acting on the corresponding flow channel opening and closing plate 12 are rotated in sequence and staggered at a certain angle and distributed on the transmission shaft.

[0063] Furthermore, the cams arranged at the outermost sides of both ends of the transmission shaft are end cams 20, and the cams located between the end cams 20 on both sides are middle cams 13;

[0064] The outer edge curve of the middle cam 13 is a middle cam conventional opening and closing curve 1301, a middle cam speed-increasing curve 1302, a middle cam closing curve 1303 and a middle cam speed-increasing curve 1302 which are connected end to end in sequence;

[0065] The outer edge curve of the end cam 20 is an end cam conventional opening and closing curve 2001, an end cam closing curve 2002 and an end cam speed-increasing curve 2003 which are connected end to end.

[0066] The distances between the speed-increasing curve, conventional opening and closing curve, and closed curve of each cam and the corresponding channel opening and closing plate's dwelling contact points and the transmission shaft increase in sequence; the dwelling contact point refers to the point where the corresponding curve contacts the channel opening and closing plate when the cam rotates and dwells at a certain angle.

[0067] When the regular opening and closing curve of the cam contacts the small roller 18 of the flow channel opening and closing plate, the flow channel opening and closing plate is pushed outward, and the flow channel opening and closing plate that pushes outward opens the corresponding top high-pressure flow channel 11 section. When the closing curve of the cam contacts the small roller 18 of the flow channel opening and closing plate, the flow channel opening and closing plate retracts, and the retracted flow channel opening and closing plate closes the corresponding top high-pressure flow channel 11 section.

[0068] When a certain cam contacts the corresponding flow channel opening and closing plate through a closed curve, its adjacent cam contacts the corresponding flow channel opening and closing plate through a speed-increasing curve, and the remaining cams contact the corresponding flow channel opening and closing plates through conventional opening and closing curves.

[0069] Furthermore, the number of layouts is five, the corresponding number of flow channel opening and closing plates is also five, and the total number of cams is also five, of which the number of end cams 20 is two, and the number of middle cams 13 is three. The closed curves on the five cams are rotated and staggered by 72° in sequence and distributed on the transmission shaft.

[0070] Furthermore, a slide groove 1106 is provided on one side of each flow channel opening and closing plate on the top high-pressure flow channel 11. The flow channel opening and closing plate is set on the slide groove 1106 and can move back and forth along the slide groove 1106 to open and close the top high-pressure flow channel 11; the slide groove 1106 is arranged on both sides of the air outlet.

[0071] Furthermore, the upper end of the side wall flow channel 6 is connected to the compressor 1 through the top high-pressure flow channel 11, and the lower end of the side wall flow channel 6 is connected to the bottom collector 3 through the suction outlet 606. A negative pressure suction hole 603 is provided on the side wall of the side wall flow channel 6 close to the blackboard, and an opening and closing plate 7 is provided in the side wall flow channel 6. The opening and closing plate 7 is connected to the side wall flow channel 6 through a rotating shaft, and the rotating shaft is connected to a rotating transmission mechanism. The rotating transmission mechanism drives the opening and closing plate 7 to rotate through the rotating shaft to realize the opening or closing of the negative pressure suction hole 603 of the side wall flow channel 6. The bottom collector 3 is connected to the purified air flow channel 608, and the purified air flow channel 608 is arranged below the side wall flow channel 6; the purified air inlet 607 of the purified air flow channel 608 is connected to the bottom collector 3, and the purified air outlet 609 of the purified air flow channel 608 is connected to the outside, and a filter element is provided in the purified air flow channel 608.

[0072] Furthermore, a spring spring 8 is connected to the rotating shaft or the opening and closing plate 7; the rotary transmission mechanism includes a No. 1 piston 16, an inner compression piston cylinder 15, and a No. 2 piston 14. The No. 1 piston 16 and the No. 2 piston 14 are respectively arranged at both ends of the inner compression piston cylinder 15. The No. 1 piston 16 is connected to the driving device. The spring spring 8 ensures that the No. 2 piston 14 always maintains contact and connection with the opening and closing plate 7. A medium is filled between the No. 1 piston 16 and the No. 2 piston 14 in the inner compression piston cylinder 15; the driving device drives the No. 1 piston 16 to move back and forth along the inner compression piston cylinder 15, thereby driving the No. 2 piston 14 to move back and forth along the inner compression piston cylinder 15, and the No. 2 piston 14 pushes the opening and closing plate 7 to rotate around the rotating shaft;

[0073] A protrusion is provided at the bottom of the flow channel opening and closing plate, and an inclined step is provided on the outer ring of the No. 1 piston 16. The protrusion fits with the inclined step. During the back and forth movement of the flow channel opening and closing plate, the protrusion squeezes the No. 1 piston 16 through the inclined step to move back and forth along the inner compression piston cylinder 15. When the flow channel opening and closing plate adjacent to the side wall flow channel 6 closes the corresponding top high-pressure flow channel 11 outlet, the negative pressure suction hole 603 of the side wall flow channel 6 is opened.

[0074] The internal compression piston cylinder 15 is installed in the piston cylinder mounting groove 601 of the side wall flow channel 6. The side wall flow channel 6 is connected to the side end of the blackboard through the blackboard mounting groove 602. The side wall flow channel 6 is provided with a negative pressure suction flow channel 604 in the vertical direction. The negative pressure suction hole 603 is connected to the negative pressure suction flow channel 604. The upper end and the lower end of the negative pressure suction flow channel 604 are respectively connected to the top high-pressure flow channel 11 and the bottom collector 3.

[0075] A filter screen 4 and a formaldehyde catalytic filter 5 are provided in the bottom collector 3 in sequence, and a filter core is provided in the purified air flow duct 608; and the large amount of airflow generated thereby flows out from the air outlets on both sides of the equipment after filtering and purification, thereby achieving air purification in the classroom.

[0076] Furthermore, the bottom collector 3 is connected to a low-speed pump.

[0077] Working principle of the present invention: Figure 1As shown, the present invention provides a blackboard cleaning device. Initially, the end cam 20 and the middle cam 13 of the device are in contact with the small roller 18 through the conventional opening and closing curve ends. At this time, the flow channel opening and closing plate 12 is in a certain opening and closing position under the action of the return spring 17 and the small roller 18. At the same time, the compressor 1 and the low-speed pump are turned on, allowing the airflow to flow out of the top high-pressure flow channel 11 and into the bottom collector 3. Because the fluid has a Coanda effect, the high-speed airflow moves along the blackboard plane after flowing out of the outlet flow channel 1105 and then enters the bottom collector 3. At the same time, due to the Bernoulli principle, the local pressure of the high-speed airflow is low. Therefore, when the airflow moves at high speed along the plane of the blackboard 2, the normal-pressure air within a certain range outside the blackboard 2 will move closer to the plane of the blackboard 2 under the action of low pressure, thereby achieving the effect of a small amount of high-speed airflow driving and curling a large amount of external airflow. Part of the chalk dust wiped off is directly pushed by the high-speed airflow and falls into the bottom collector 3. The other part of the chalk dust escapes and floats near the plane of the blackboard 2. Under the action of the Bernoulli principle, the air outside the blackboard 2 moves toward the blackboard surface and also enters the bottom collector 3 at the same time, thereby cleaning the floating dust near the blackboard.

[0078] The blackboard surface 2 is divided into five areas from left to right. When students wipe the blackboard from left to right, when the sensor detects that the blackboard eraser is on the left side of the five blackboard areas, it will drive the stepper motor 9 to rotate, and then drive the transmission shaft 19 to rotate, and then drive the five cams corresponding to the five different blackboard areas 2 to rotate.

[0079] At the next moment, the leftmost cam rotates, causing the small roller 18 to no longer contact the end cam's regular opening and closing curve 2001 of the end cam 20, but instead contact the end cam's closed curve 2002. At this point, the small roller is squeezed by the cam, driving the connected flow channel opening and closing plate 12 to move along the slide groove 1106 toward the return spring mounting hole 1103, thereby compressing the return spring 17 and simultaneously closing the air outlet formed by the flow channel opening and closing plate 12 and the inner wall of the top high-pressure flow channel 11. At the same time, as the flow channel opening and closing plate moves forward to close the air outlet, the protrusion at the bottom of the opening and closing plate squeezes the inclined surface of the No. 1 piston 16, causing the No. 1 piston 16 to compress the liquid in the piston cylinder 15 inward, thereby causing the No. 2 piston 14 to extend. The protrusion at the front of the No. 2 piston 14 presses against the opening and closing plate 7, causing it to rotate around the rotating axis, opening the negative pressure suction hole 603 while compressing the connected spring 8. At this time, the cavity of the bottom collector 3 is connected to the side wall flow channel 6 through the suction outlet 606. When the transmission shaft 19 rotates, not only the end cam 20 corresponding to the No. 1 plate rotates, but the other four cams also rotate. The curve of the middle cam 13 of the No. 2 plate in contact with the small roller 18 changes from the conventional opening and closing curve 1301 of the middle cam to the speed-increasing curve 1302 of the middle cam. At this time, the flow channel opening and closing plate 12 corresponding to the No. 2 plate moves in the direction away from the return spring mounting hole 1103 under the action of the return spring 17, and the size of the air outlet formed by the flow channel opening and closing plate 12 and the wall of the top high-pressure flow channel 11 is expanded; at the same time, the airflow that was originally divided into 5 parts is divided into four parts and flows out from the remaining four flow channels due to the closure of a certain flow channel. Since the opening of the flow channel corresponding to the No. 2 plate increases and the air resistance decreases, more airflow enters from the flow channel of the No. 2 plate, and when passing through the outlet flow channel 1105, it propagates along the black board surface 2 in the form of high-speed airflow. Since the outlet flow channels 1105 corresponding to the five panels are of the same size, the cam drive only changes the resistance adjustment channel of the previous stage, so the airflow into the flow channel of panel No. 2 increases, and the flow rate increases. Therefore, when erasing the blackboard of panel No. 1, the flow channel corresponding to panel No. 1 is closed. At this time, there is no airflow on panel No. 1 and it is unable to clean the floating powder on the panel. However, the negative pressure suction hole 603 of the side wall flow channel 6 adjacent to the left side of panel No. 1 is opened, so that the floating powder on panel No. 1 is subjected to the negative pressure suction effect. At the same time, due to the increase in the flow rate of the airflow on the right side of panel No. 2, the pressure is reduced, and the curling and guiding ability of the surrounding air is enhanced, which can further clean the floating powder on panel No. 1.

[0080] After cleaning board No. 1, the student moves to board No. 2. This time, the sensor transmits a signal to the main controller system, causing stepper motor 9 to rotate again, causing the contact curve between small roller 18 and the end cam corresponding to board No. 1 to change from end cam closed curve 2002 to end cam accelerated curve 2003. The restored airflow cleans away the chalk dust generated during cleaning board No. 1. Simultaneously, the contact curve between small roller 18 and the middle cam corresponding to board No. 2 changes from middle cam accelerated curve 1302 to middle cam closed curve 1303. The contact curve between small roller 18 and the middle cam corresponding to board No. 3 changes from middle cam normal open-close curve 1301 to middle cam accelerated curve 1302. Ultimately, the airflow from board No. 2 is suspended, while the airflow from boards No. 1 and No. 3 increases, enhancing their ability to curl and entrain floating chalk around the blackboard, thereby suppressing the dispersal of dust from board No. 2. Afterwards, the airflow on panel 3 stops, while the flow rates on panels 2 and 4 increase, working together to suppress dust diffusion on panel 3. The airflow on panel 4 stops, while the flow rates on panels 3 and 5 increase, working together to suppress dust diffusion on panel 4. The airflow on panel 5 stops, while the flow rate on panel 4 increases, and the negative pressure suction holes 603 in the sidewall flow channel 6 adjacent to panel 5 open, working together to suppress dust diffusion on panel 5.

[0081] The above are only preferred embodiments of the present invention, and certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the scope of the patent application of the present invention still fall within the scope of protection of the present invention.

Claims

1. A blackboard cleaning device, characterized in that: It includes a top high-pressure flow channel, a bottom collector, a side wall flow channel and a compressor. The top high-pressure flow channel and the bottom collector are respectively arranged at the top and bottom of the blackboard, the side wall flow channels are respectively arranged on both sides of the blackboard, and the air outlet of the compressor is connected to the top high-pressure flow channel; The air outlet of the top high-pressure flow channel is provided with a flow channel opening and closing plate assembly, which is connected to a driving device. The driving device drives the flow channel opening and closing plate assembly to move back and forth, thereby opening and closing the air outlet of the top high-pressure flow channel; The driving device includes a transmission mechanism and a motor, and the motor is connected to the flow channel opening and closing plate assembly through the transmission mechanism; The transmission mechanism includes a transmission shaft and a cam, the transmission shaft is arranged horizontally, the cam is sleeved on the transmission shaft, and the motor is connected to the transmission shaft; The cam is in contact with the flow channel opening and closing plate assembly, which is connected to a return spring. The return spring keeps the flow channel opening and closing plate assembly in contact with the cam. The motor drives the cam to rotate through the transmission shaft, and the cam drives the flow channel opening and closing plate assembly to move back and forth, thereby opening or closing the air outlet of the top high-pressure flow channel. The blackboard is divided into multiple sections along the length direction; The top high-pressure flow channel is provided with a plurality of air outlets distributed along the length direction of the blackboard, and each air outlet is arranged one-to-one corresponding to each blackboard surface. The flow channel opening and closing plate assembly includes a plurality of flow channel opening and closing plates arranged in sequence along the length direction of the blackboard, and each flow channel opening and closing plate is respectively arranged in a corresponding air outlet; The number of cams is consistent with the number of flow channel opening and closing plates, and they are arranged one by one. Multiple cams are arranged on the transmission shaft in sequence along the length of the blackboard. Each flow channel opening and closing plate is in contact with a corresponding cam, and each flow channel opening and closing plate is connected to a return spring. The blackboard cleaning device also includes a blackboard eraser, a controller and a sensor. A locator is provided on the blackboard eraser, and an arc-shaped guide plate is provided on the top of the blackboard eraser. The arc-shaped guide plate guides the airflow blowing from above to one side of the blackboard eraser; the locator is arranged on one side of the blackboard eraser, and the tail end of the arc-shaped guide plate is arranged along the other side of the blackboard eraser. The arc-shaped guide plate guides the upper airflow to the side of the blackboard eraser, so that the airflow continues to move downward. The arc-shaped surface of the arc-shaped guide plate protrudes outward, and the controller is connected to the sensor and the motor respectively. The sensor is arranged on one side of the blackboard for detecting the locator on the blackboard eraser. When the sensor detects that the locator on the blackboard eraser is on the corresponding blackboard page, the air outlet corresponding to the page is closed, and the air outlets corresponding to the other pages are all opened.

2. The blackboard cleaning device according to claim 1, characterized in that: The closed curves on each cam are distributed on the transmission shaft at staggered angles.

3. The blackboard cleaning device according to claim 2, characterized in that: The cams arranged on the outermost sides of the transmission shaft are end cams, and the cams located between the end cams on both sides are middle cams; The outer edge curve of the middle cam is a middle cam conventional opening and closing curve (1301), a middle cam speed-increasing curve (1302), a middle cam closing curve (1303) and a middle cam speed-increasing curve (1302) connected in sequence end to end; The outer edge curve of the end cam is the end cam conventional opening and closing curve (2001), the end cam closing curve (2002) and the end cam speed-increasing curve (2003) connected in sequence end to end; The speed-increasing curve, conventional opening and closing curve and closing curve of each cam and the distance between the contact point of the corresponding flow channel opening and closing plate and the transmission shaft increase in sequence; When the regular opening and closing curve of the cam contacts the flow channel opening and closing plate, the flow channel opening and closing plate is pushed outward, and the flow channel opening and closing plate pushes outward to open the corresponding top high-pressure flow channel section. When the closing curve of the cam contacts the flow channel opening and closing plate, the flow channel opening and closing plate retracts, and the retracted flow channel opening and closing plate closes the corresponding top high-pressure flow channel section. When a certain cam contacts the corresponding flow channel opening and closing plate through a closed curve, its adjacent cam contacts the corresponding flow channel opening and closing plate through a speed-increasing curve, and the remaining cams contact the corresponding flow channel opening and closing plates through conventional opening and closing curves.

4. The blackboard cleaning device according to claim 1, characterized in that: A chute is provided on one side of each flow channel opening and closing plate on the top high-pressure flow channel. The flow channel opening and closing plate is arranged on the chute and can move back and forth along the chute to open and close the top high-pressure flow channel.

5. The blackboard cleaning device according to claim 1, characterized in that: The upper end of the side wall flow channel is connected to the compressor through the top high-pressure flow channel, and the lower end of the side wall flow channel is connected to the bottom collector. A negative pressure suction hole is provided on the side wall of the side wall flow channel close to the blackboard. An opening and closing plate is provided in the side wall flow channel. The opening and closing plate is connected to the side wall flow channel through a rotating shaft. The rotating shaft is connected to a rotating transmission mechanism. The rotating transmission mechanism drives the opening and closing plate to rotate through the rotating shaft to realize the opening or closing of the negative pressure suction hole of the side wall flow channel. The bottom collector is connected to a purified air flow channel, and the purified air flow channel is arranged below the side wall flow channel.

6. The blackboard cleaning device according to claim 1, characterized in that: A spring is connected to the rotating shaft or the opening and closing plate; the rotary transmission mechanism includes a No. 1 piston, an inner compression piston cylinder, and a No. 2 piston, which are respectively arranged at the two ends of the inner compression piston cylinder. The No. 1 piston is connected to the driving device, and the spring keeps the No. 2 piston in contact with the opening and closing plate. The driving device drives the No. 1 piston to move back and forth along the inner compression piston cylinder, thereby driving the No. 2 piston to move back and forth along the inner compression piston cylinder, and the No. 2 piston pushes the opening and closing plate to rotate around the rotating shaft; There is a protrusion at the bottom of the flow channel opening and closing plate, and an inclined step is provided on the outer ring of piston No.

1. The protrusion fits with the inclined step. During the back and forth movement of the flow channel opening and closing plate, the protrusion squeezes piston No. 1 through the inclined step to move back and forth along the inner compression piston cylinder. When the flow channel opening and closing plate adjacent to the side wall flow channel closes the corresponding top high-pressure flow channel outlet, the negative pressure suction hole of the side wall flow channel is opened.

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