Roller shutter type blackboard for teaching blackboard writing

Abstract

The invention provides a roller shutter type blackboard for teaching blackboard writing. Comprising a bottom front shaft, a power adapter, a rotating shaft, an under-plate shaft, a frame, a backlight plate, an on-plate shaft, a top front shaft, a top front cylinder, an on-plate cylinder, a main curtain, a curtain hole, curtain teeth, a glass plate, an auxiliary curtain, an under-plate cylinder, a rotating cylinder, a bottom front cylinder, shifting teeth, a bottom rear shaft, a bottom rear cylinder, a damper, a tensioning cylinder, a tensioning shaft, a tensioning spring, a hanging seat and a line grid. The power adapter, the backlight plate and the glass plate form a backlight mechanism, the curtain teeth and the curtain holes form a synchronizing mechanism, the tensioning cylinder, the tensioning spring and the connecting rod form a tightening mechanism, line grids on the blackboard can be displayed and hidden, after the backlight plate is lightened, the line grids on the auxiliary curtain can be seen by the sight line penetrating through the main curtain, and during writing, the line grids cannot be bent under the guidance of the line grids, so that the blackboard is convenient to use. When the line grids are not needed, the backlight plate is closed, the guide line grids cannot be seen on the main curtain any more, the content is clean and clear, the eyes of students are not prone to fatigue, and the teaching board is suitable for foreign language and pinyin blackboard writing teaching.

Description

Technical Field

[0001] The present invention relates to a blackboard used in a classroom, and more particularly to a rolling blackboard for teaching writing, belonging to the technical field of teaching equipment. Background Art

[0002] Blackboards or whiteboards are essential teaching equipment in classrooms. In modern classrooms or meeting rooms, ordinary whiteboards or electronic whiteboards are usually equipped. The functions of ordinary whiteboards are too simple, and the costs of electronic whiteboards are too high. Simple blackboards, whether made of wood, cement or plastic, are fixed as a whole piece, with a small area and a low height, and the writing range is limited. To expand the writing range and enable the blackboard to accommodate more words or content, most classrooms, especially large classrooms in universities, are now equipped with push-pull blackboards. The blackboards are usually divided into four pieces, up, down, left and right, and there are also six-piece blackboards in larger large classrooms. With the development of technology, there are currently some curtain blackboards, such as: A curtain-type plastic film blackboard is provided with a wooden blackboard body and a frame. Drums are arranged at both left and right ends. A sufficient amount of black plastic film is wound on the left drum. The blackboard surface is covered with a plastic film body for writing, and two upper and lower pressure bars and a sliding pressure bar therebetween, as well as two upper and lower elastic nails are designed. The curtain blackboard (CN 104085229 A) is provided with an upper drum and a lower drum above and below the blackboard respectively. One end of a curtain cloth is wound on the upper drum and the other end is wound on the lower drum. A pressure curtain drum is arranged below the upper drum and above the lower drum respectively. A crank and a crank handle are connected to the right end of the shaft of the lower drum. When erasing the blackboard, the crank handle is rotated to rotate the lower drum to pull the curtain cloth downward and wind it on the lower drum. During the process that the curtain cloth is continuously wound on the lower drum, the dust removal brush below the lower drum will automatically erase the chalk words on the blackboard. The blackboard curtain type is easy to clean the blackboard (CN 112248686 A), including a housing, a fixing plate, a switch, a stand, a power cord and a transmission mechanism. When the switch is started, the motor rotates, driving a worm, and the worm then drives a worm wheel to rotate, and then drives a round rod and a roller to rotate. The blackboard curtain arranged on the round rod will slide correspondingly, achieving the advantage of facilitating the movement of the blackboard for cleaning, improving the efficiency of cleaning the blackboard. The fallen dust will be blown by a blower along the slide rail to the left side, and then blocked by a baffle and finally fall into a storage box.

[0003] In addition, there is also a curtain blackboard abroad, which is divided into two left and right curtains. A number of horizontal lines are printed on both curtains, which can be pushed up and down, thereby expanding the writing range, reducing the weight of the blackboard and facilitating writing. All of the above blackboards have a defect. If there are no grid lines on the blackboard, there will be no reference lines for writing. For those who lack writing practice, the written sentences are prone to bending, not neat enough and not good-looking enough. If grid lines are pre-drawn on the blackboard, the grid lines cannot be hidden, and the grid lines will interfere with the written words or content, and the students' eyes are prone to fatigue. Summary of the Invention

[0004] The object of the present invention is to provide a rolling blackboard for teaching writing on which the line grids on the blackboard can be both displayed and hidden.

[0005] The technical problem to be solved by the present invention is realized through the following technical solutions: The blackboard includes a front bottom shaft (1), a power adapter (2), a rotating shaft (3), a bottom board shaft (4), a frame (5), a backlight board (6), an LED (7), a top board shaft (8), a bearing (9), a front top shaft (10), a front top cylinder (11), a top board cylinder (12), a main curtain (13), a rotating part (14), curtain holes (15), curtain teeth (16), a glass plate (17), a secondary curtain (18), a bottom board cylinder (19), a rotating cylinder (20), a front bottom cylinder (21), a shifting tooth (22), a rear bottom shaft (23), a rear bottom cylinder (24), a damper (25), a tensioning cylinder (26), a tensioning shaft (27), a tensioning spring (28), a suspension ring (29), a connecting rod (30), a shaft pin (31), a suspension seat (32) and a line grid (33).

[0006] The front top cylinder (11), the front bottom cylinder (21), the rear bottom cylinder (24), the tensioning cylinder (26) and the rotating cylinder (20) form a main curtain cylinder group, the top board cylinder (12) and the bottom board cylinder (19) form a secondary curtain cylinder group, the power adapter (2), the backlight board (6) and the glass plate (17) form a backlight mechanism, the curtain teeth (16) and the curtain holes (15) form a synchronization mechanism, the tensioning cylinder (26), the tensioning spring (28) and the connecting rod (30) form a tensioning mechanism. One end of the front bottom cylinder (21) is provided with a shifting tooth (22), and a damper (25) is arranged between the rear bottom shaft (23) and the rear bottom cylinder (24), which is a felt with a phosphor bronze reed to ensure the stability of operation, slow down the rotation speed of the rotating shaft, avoid the rebound of the rolling curtain. The rotating shaft (3) and the rotating cylinder (20) are arranged on the lower half of the frame (5) and above the rear bottom cylinder (24), the bottom board shaft (4) and the bottom board cylinder (19) are arranged on the lower half of the frame (5) and above the front bottom cylinder (21), the top board shaft (8) and the top board cylinder (12) are arranged on the upper half of the frame (5) and above the bottom board cylinder (19), the tensioning cylinder (26) and the tensioning shaft (27) are arranged on the side of the top of the frame (5) away from the observer. A connecting rod (30) is arranged between the suspension seat (32) and the tensioning shaft (27). Both ends of the connecting rod (30) are set as bushings, and bearings are embedded in the bushings. The top end of the connecting rod (30) is movably connected to the shaft pin (31) on the suspension seat (32) through a bearing, and the bottom end of the connecting rod (30) is movably connected to the tensioning shaft (27) through a bearing. A circular ring is arranged on the outer side of the bushing at the bottom end of the connecting rod (30) so as to hook the tensioning spring (28) and be elastically connected to the suspension ring (29).

[0007] A vertical backlight panel (6) is provided between the upper-board cylinder (12) and the lower-board cylinder (19). An auxiliary curtain (18) is wound around the upper-board cylinder (12) and the lower-board cylinder (19) to form a long strip in the shape of "0", and the backlight panel (6) is enclosed within the "0" shape. A number of horizontal grid lines (33) are printed on the auxiliary curtain (18). Along one side of the auxiliary curtain (18) around the "0" shape for one week, saw-tooth-shaped curtain teeth (16) are provided. A glass plate (17) is provided between the outer part of the auxiliary curtain (18) and the backlight panel (6). The two vertical edges of the glass plate (17) and the backlight panel (6) are respectively connected to the inner sides of the two vertical edges of the frame (5) through glass glue. A main curtain (13) is wound around the bottom front cylinder (21), the bottom rear cylinder (24), the tensioning cylinder (26), the rotary cylinder (20), the top front cylinder (11) and then back to the bottom front cylinder (21). The main curtain (13) is wound into a rotary part (14) that can increase the area of the rolling blackboard between the tensioning cylinder (26), the rotary cylinder (20) and the top front cylinder (11), and its cross-sectional shape is a long strip in the shape of "U". All the main curtains (13) on the main curtain cylinder group are wound into a concave shape with a long strip cross-sectional shape. Under the action of the tensioning spring (28), the main curtain (13) is tightened. A number of curtain holes (15) are provided along one week on one side of the main curtain (13). At the overlapping part of the auxiliary curtain (18) and the main curtain (13), all the curtain teeth (16) on the auxiliary curtain (18) respectively penetrate into the corresponding curtain holes (15) on the main curtain (13).

[0008] During use, the shift tooth (22) is toggled, and the bottom front cylinder (21) rotates. Under the traction of the main curtain (13), all the main curtain cylinder groups rotate. Under the action of the tensioning mechanism, the main curtain (13) closely adheres to the auxiliary curtain (18) to ensure that all the curtain teeth (16) outside the backlight panel (6) penetrate into the corresponding curtain holes (15). Under the action of the synchronization mechanism, the auxiliary curtain (18) and the auxiliary curtain cylinder group rotate together with the main curtain (13). Visually, the grid lines (33) on the auxiliary curtain (18) will move together with the main curtain (13). After the backlight panel (6) is lit, the line of sight can pass through the main curtain to see the grid lines on the auxiliary curtain.

[0009] In summary, the main curtain (13) is used as a blackboard for writing. The grid lines (33) on the auxiliary curtain (18) serve as an invisible bottom pattern of the blackboard under the illumination of the backlight panel (6), which is convenient for teachers to write and teach. When writing, it can be guided by the grid lines without bending or deviation, so that the words or sentences are written neatly and regularly. When the writing area is full, the shift tooth (22) is toggled to move the main curtain (13) upward, and the auxiliary curtain (18) and the grid lines (33) move upward accordingly. The written content is moved above the whiteboard or to the rotary part (14) or the back of the main curtain (34). At this time, the area at the backlight panel (6) is the new writing area and can continue to be written. After writing is completed, the backlight panel (6) is turned off, and the guiding grid lines (33) can no longer be seen on the main curtain (13), making the writing content on the main curtain (13) clear and clean.

[0010] The main curtain (13) is a semi-transparent, frosted, dark grey or dark green plastic curtain, which is embedded with a plurality of transparent fibers to enhance the strength of the main curtain (13) and prevent the main curtain (13) from being deformed when being pulled or in high temperature seasons. The material of the auxiliary curtain (18) is the same as that of the main curtain (13), but is colorless and fully transparent. The glass plate (17) is a high-strength thin tempered glass to ensure that the writing area is flat and can reduce the external force on the backlight plate (6) to prevent the backlight plate (6) from being worn when the auxiliary curtain (18) is rolled, or when writing, the backlight plate (6), the main curtain (13) and the auxiliary curtain (18) are deflated by the writing pen.

[0011] Due to the adoption of the above technical solution, the advantages and positive effects of the present invention are: the grid on the blackboard can be displayed or hidden. After the backlight is turned on, the line of sight can pass through the main curtain to see the grid on the auxiliary curtain, which is convenient for teachers to write and teach. When writing, the text or sentence can be written in a standardized and neat manner without bending or deflection under the guidance of the grid. When the grid is not needed, the backlight is turned off, the guide grid can no longer be seen on the main curtain, the content on the main curtain is clean and clear, the students' eyes are not easily fatigued, and the existence of the rotating part can increase the use area of ​​the blackboard. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The present invention is further described below in conjunction with the accompanying drawings and embodiments. The present invention has the following 5 drawings: Figure 1 is a front view of the present invention, Figure 2 It is a partial sectional view of the main view. Figure 3 It is a left sectional view of the present invention, Figure 4 This is the left view after the main curtain and auxiliary curtain are separated and the backlight panel and glass panel are removed. Figure 5 This is a partial enlarged view of the left view after removing the plate shaft and plate cylinder.

[0013] The numbers in the accompanying drawings represent the following: 1. Bottom front shaft, 2. Power adapter, 3. Rotating shaft, 4. Lower shaft, 5. Frame, 6. Backlight, 7. LED, 8. Upper shaft, 9. Bearing, 10. Top front shaft, 11. Top front cylinder, 12. Upper cylinder, 13. Main curtain, 14. Rotating part, 15. Curtain hole, 16. Curtain teeth, 17. Glass plate, 18. Auxiliary curtain, 19. Lower cylinder, 20. Rotating cylinder, 21. Bottom front cylinder, 22. Gear, 23. Bottom rear shaft, 24. Bottom rear cylinder, 25. Damper, 26. Tensioning cylinder, 27. Tensioning shaft, 28. Tensioning spring, 29. Lifting ring, 30. Connecting rod, 31. Axis pin, 32. Suspension seat, 33. Wire grid, 34. Back of main curtain, DETAILED DESCRIPTION

[0014] 1. According to Figures 1 to 5 , the blackboard includes a bottom front shaft (1), a power adapter (2), a rotating shaft (3), a shaft under the board (4), a frame (5), a backlight board (6), an LED (7), a shaft on the board (8), a bearing (9), a top front shaft (10), a top front cylinder (11), a cylinder on the board (12), a main curtain (13), a rotating part (14), curtain holes (15), curtain teeth (16), a glass plate (17), an auxiliary curtain (18), a cylinder under the board (19), a rotating cylinder (20), a bottom front cylinder (21), a tooth (22), a bottom rear shaft (23), a bottom rear cylinder (24), a damper (25), a tensioning cylinder (26), a tensioning shaft (27), a tensioning spring (28), a hanging ring (29), a connecting rod (30), a shaft pin (31), a hanging seat (32), and a wire grid (33).

[0015] 2. The top front cylinder (11), the bottom front cylinder (21), the bottom rear cylinder (24), the tensioning cylinder (26), and the rotating cylinder (20) form a main curtain cylinder group, the cylinder on the board (12) and the cylinder under the board (19) form an auxiliary curtain cylinder group, the power adapter (2), the backlight board (6), and the glass plate (17) form a backlight mechanism, the curtain teeth (16) and the curtain holes (15) form a synchronization mechanism, the tensioning cylinder (26), the tensioning spring (28), and the connecting rod (30) form a tensioning mechanism, and the main curtain in front of the backlight board (6) is the writing area.

[0016] 3. The frame (5) is surrounded by flat 0-shaped hollow aluminum alloy profiles, with four sides on the top, bottom, left, and right, and the overall shape is a square. The four corners are connected by internal corner bars and screws. On one side of the bottom of the frame (5) close to the observer, there is a bottom front shaft (1) and a bottom front cylinder (21). One end of the bottom front cylinder (21) is provided with a tooth (22). Above the other end of the bottom front cylinder (21) and on the inner wall of the frame (5), there is a power adapter (2). The power adapter is provided with an LED brightness adjustment potentiometer. The long rotating shaft of the potentiometer passes through the outer shell of the power adapter and passes through the attached frame (5). A brightness adjustment knob is arranged on the potentiometer rotating shaft outside the frame (5). On the side of the bottom of the frame (5) far from the observer, there is a bottom rear shaft (23) and a bottom rear cylinder (24). A damper (25) is arranged between the bottom rear shaft (23) and the bottom rear cylinder (24) to prevent the bottom rear cylinder (24) from rotating freely.

[0017] 4. At the lower part of the frame (5) and above the bottom rear cylinder (24), there are a rotary shaft (3) and a rotary cylinder (20). At the lower part of the frame (5) and above the bottom front cylinder (21), there are a shaft under the plate (4) and a cylinder under the plate (19). At the upper part of the frame (5) and above the cylinder under the plate (19), there are a shaft above the plate (8) and a cylinder above the plate (12). The circumferences of the cylinder above the plate (12) and the cylinder under the plate (19) are tangent to the edge of the frame (5). On the side of the top of the frame (5) close to the observer, there are a top front shaft (10) and a top front cylinder (11). On the side of the top of the frame (5) far from the observer, there are a tensioning cylinder (26) and a tensioning shaft (27). Bearings (9) are sleeved at both ends of each of the above-mentioned shafts, and each of the above-mentioned cylinders can rotate around its respective shaft.

[0018] 5. There are notches left on the rear walls of both side frames (5) close to the back of the main curtain (34). Bearing seats and bearings are embedded in the notches. The bearing seats are connected to the inside of the frame (5). Except that the length of the tensioning shaft (27) is slightly shorter than the inner distance between the two vertical sides of the frame (5), the lengths of the other shafts are slightly longer than the inner distance between the two vertical sides of the frame (5). Except for the two ends of the tensioning shaft (27), the two ends of the other shafts respectively penetrate into the bearings at the corresponding positions. On both sides of the bottom surface of the top plate of the frame (5), there are suspension seats (32) and suspension rings (29). A shaft pin (31) is provided inside the suspension seat (32). A connecting rod (30) is provided between the suspension seat (32) and the tensioning shaft (27). Both ends of the connecting rod (30) are set as bushings, and bearings are embedded in the bushings. The top end of the connecting rod (30) is movably connected to the shaft pin (31) on the suspension seat (32) through a bearing, and the bottom end of the connecting rod (30) is movably connected to the tensioning shaft (27) through a bearing. A circular ring is provided on the outer side of the bushing at the bottom end of the connecting rod (30) so as to hook the tensioning spring (28) and be elastically connected to the suspension ring (29).

[0019] 6. A vertical backlight panel (6) is provided between the upper cylinder (12) and the lower cylinder (19) of the board. A plurality of LEDs (7) are embedded in the backlight panel (6). An auxiliary curtain (18) is rolled up on the upper cylinder (12) and the lower cylinder (19) of the board and rolled up into a long strip O-shape. The backlight panel (6) is surrounded in the O-shape. A plurality of horizontal grids (33) are printed on the auxiliary curtain (18). A saw-like curtain teeth (16) are provided on one side of the auxiliary curtain (18) along the O-shape. A glass panel (17) is provided between the outer part of the auxiliary curtain (18) and the backlight panel (6). The two vertical edges of the glass panel (17) and the backlight panel (6) are connected to the inner sides of the two vertical edges of the frame (5) through glass glue respectively. The auxiliary curtain (18) is provided along the bottom front cylinder (21), the bottom rear cylinder (24), and the tension cylinder (2 6) The main curtain (13) is rolled up on the rotating drum (20), the top front drum (11) and then the bottom front drum (21). The main curtain (13) is rolled up between the tensioning drum (26), the rotating drum (20) and the top front drum (11) to form a rotating portion (14) that can increase the area of ​​the rolling curtain blackboard. Its cross-sectional diagram is a long U-shaped strip. All the main curtains (13) on the main curtain drum group are rolled up into a concave shape with a long cross-sectional diagram. Under the action of the tensioning spring (28), the main curtain (13) is tightened. A plurality of curtain holes (15) are arranged around one side of the main curtain (13). At the overlapping portion of the auxiliary curtain (18) and the main curtain (13), all the curtain teeth (16) on the auxiliary curtain (18) are respectively inserted into the corresponding curtain holes (15) on the main curtain (13).

[0020] 7. When in use, the tooth (22) is moved, and the bottom front tube (21) rotates. Under the involvement of the main curtain (13), the main curtain tube group rotates completely. Under the action of the tensioning mechanism, the tension of the rolling curtain is automatically adjusted to prevent slackness, thereby avoiding the problem of wrinkles or deviation of the rolling curtain. The main curtain (13) is closely attached to the auxiliary curtain (18), ensuring that all the curtain teeth (16) at the outer side of the backlight plate (6) are fully inserted into the corresponding curtain holes (15). Under the action of the synchronization mechanism, the auxiliary curtain (18) and the auxiliary curtain tube group rotate together with the main curtain (13). In terms of visual effect, the grid (33) on the auxiliary curtain (18) moves together with the main curtain (13).

[0021] 8. The main curtain (13) is a translucent, frosted, dark gray or dark green plastic curtain with a plurality of transparent fibers embedded therein to enhance the strength of the main curtain (13) and prevent the main curtain (13) from deforming when being pulled or in high temperature seasons. The material of the auxiliary curtain (18) is the same as that of the main curtain (13), but is colorless and fully transparent.

[0022] 9. The power adapter (2) contains an LED driver chip. One end of the power adapter (2) is connected to the mains via a power switch. The output end of the LED driver chip is connected to the LED (7) via a wire. After the backlight panel (6) is lit, the line grid (33) on the auxiliary curtain (18) can be seen through the main curtain (13).

[0023] 10. In summary, the main curtain (13) serves as a blackboard for writing. The line grid (33) on the auxiliary curtain (18) serves as a hidden background of the blackboard under the illumination of the backlight panel (6), facilitating teachers' writing and teaching. When writing, it can be neat and regular under the guidance of the line grid (33). When the writing area is full, turn the tooth (22) to move the main curtain (13) upward, and the auxiliary curtain (18) and the line grid (33) will move upward accordingly. According to the intensity of the ambient light, adjust the brightness of the LED through the potentiometer in the power adapter to obtain the best backlight effect.

[0024] 11. The written content is moved above the blackboard, or to the rotary part (14) or the back of the main curtain (34). At this time, the area of the backlight panel (6) becomes the new writing area, and writing can continue. After writing, turn off the backlight panel (6), and the guiding line grid (33) can no longer be seen on the main curtain (13), making the writing content on the main curtain (13) clean and clear, and not easily tiring students' eyes.

[0025] 12. When needed, the tooth (22) can also be turned downward, and the main curtain (13) will move downward. The text above the blackboard, or on the rotary part (14) or the back of the main curtain (34) can move downward in sequence, and the previously written content can be seen.

[0026] 13. The shape or structure of the line grid (33) should be made or replaced according to different teaching contents, for the teaching needs of English, pinyin, music, calligraphy, mathematics, Chinese, programming or other courses respectively. When used for foreign language teaching, different language syntax or phonetic symbols can be compared and shown. When used for music staff teaching, the backlight panel (6) needs to be always on to identify the musical scale.

[0027] 14. The materials of the main curtain cylinder group and the auxiliary curtain cylinder group are aluminum alloy, with a wall thickness of 1.5 - 2.0 mm. The damper (25) is a felt with phosphor bronze reed to ensure the stability of operation, slow down the rotation speed of the rotating shaft, and avoid the rebound of the rolling curtain. The glass plate (17) is a high-strength thin tempered glass with a wall thickness of 2.0 - 2.2 mm, which is used to ensure the flatness of the writing area, and at the same time can reduce the external force on the backlight panel (6), preventing the backlight panel (6) from being worn when the auxiliary curtain (18) rolls, or when writing, the backlight panel (6), the main curtain (13) and the auxiliary curtain (18) from being indented by the writing pen tip. The LED is white and high-brightness.

[0028] 15. Since the technologies of the power adapter, LED brightness adjustment and backlight panel are already very mature, the relevant content in this specification will not be elaborated further. Please refer to relevant books and documents by those skilled in the art, or search online.

Claims

1. A rolling blackboard for teaching blackboard writing, comprising a power adapter (2), a rotating shaft (3), a lower shaft (4), a frame (5), a backlight panel (6), an upper shaft (8), a top front cylinder (11), an upper cylinder (12), a main curtain (13), a rotating portion (14), a curtain hole (15), curtain teeth (16), a glass plate (17), an auxiliary curtain (18), a lower cylinder (19), a rotating cylinder (20), a bottom front cylinder (21), a shifting tooth (22), and a bottom The top rear axle (23), the bottom rear cylinder (24), the damper (25), the tension cylinder (26), the tension shaft (27), the tension spring (28), the hanging ring (29), the connecting rod (30), the shaft pin (31), the hanging seat (32) and the wire grid (33), the top front cylinder (11), the bottom front cylinder (21), the bottom rear cylinder (24), the tension cylinder (26) and the rotating cylinder (20) constitute a main curtain cylinder group, and the plate upper cylinder (12) and the plate lower cylinder (19) constitute an auxiliary curtain cylinder group; Features: The power adapter (2), the backlight plate (6) and the glass plate (17) constitute a backlight mechanism, the curtain teeth (16) and the curtain holes (15) constitute a synchronization mechanism, the tensioning cylinder (26), the tensioning spring (28) and the connecting rod (30) constitute a tightening mechanism, one end of the bottom front cylinder (21) is provided with a shifting tooth (22), a damper (25) is provided between the bottom rear shaft (23) and the bottom rear cylinder (24) to prevent the bottom rear cylinder (24) from rotating freely, a rotating shaft (3) and a rotating cylinder (20) are provided at the lower half of the frame (5) and above the bottom rear cylinder (24), and a lower plate shaft (4) and a lower plate cylinder (19) are provided at the lower half of the frame (5) and above the bottom front cylinder (21). ), a plate shaft (8) and a plate cylinder (12) are provided on the upper half of the frame (5) and above the plate lower cylinder (19), a tension cylinder (26) and a tension shaft (27) are provided on the top of the frame (5) away from the observer, a connecting rod (30) is provided between the hanging seat (32) and the tension shaft (27), both ends of the connecting rod (30) are provided with shaft sleeves, bearings are embedded in the shaft sleeves, the top end of the connecting rod (30) is movably connected to the shaft pin (31) on the hanging seat (32) through the bearing, the bottom end of the connecting rod (30) is movably connected to the tension shaft (27) through the bearing, and a circular ring is provided on the outer side of the shaft sleeve at the bottom end of the connecting rod (30) so as to hook the tension spring (28) and elastically connect it with the hanging ring (29); A vertical backlight panel (6) is arranged between the upper plate cylinder (12) and the lower plate cylinder (19). Auxiliary curtains (18) are rolled up on the upper plate cylinder (12) and the lower plate cylinder (19) and rolled into a long strip O-shape. The backlight panel (6) is surrounded in the O-shape. A plurality of horizontal grids (33) are printed on the auxiliary curtain (18). Saw-shaped curtain teeth (16) are arranged on one side of the auxiliary curtain (18) along the O-shape. A glass plate (17) is arranged between the outer part of the auxiliary curtain (18) and the backlight panel (6). Two vertical edges of the glass plate (17) and the backlight panel (6) are connected to the inner sides of two vertical edges of the frame (5) through glass glue respectively. The auxiliary curtain (18) is wound along the bottom front cylinder (21), the bottom rear cylinder (24), the tension cylinder (26), the rotating cylinder (20). , the top front cylinder (11) returns to the bottom front cylinder (21) to roll up the main curtain (13), the main curtain (13) is rolled up between the tensioning cylinder (26), the rotating cylinder (20) and the top front cylinder (11) to form a rotating part (14) that can increase the area of ​​the rolling curtain blackboard, and its cross-sectional figure is a long U-shaped strip, and all the main curtains (13) on the main curtain cylinder group are rolled up into a concave shape with a long cross-sectional figure. Under the action of the tensioning spring (28), the main curtain (13) is tightened, and a plurality of curtain holes (15) are arranged around one side of the main curtain (13), and at the overlapping part of the auxiliary curtain (18) and the main curtain (13), all the curtain teeth (16) on the auxiliary curtain (18) are respectively inserted into the corresponding curtain holes (15) on the main curtain (13); When in use, the pull tooth (22) is moved, and the bottom front tube (21) rotates. Under the involvement of the main curtain (13), the main curtain tube group rotates completely. Under the action of the tensioning mechanism, the main curtain (13) is tightly attached to the auxiliary curtain (18), ensuring that all the curtain teeth (16) at the outer side of the backlight board (6) are all inserted into the corresponding curtain holes (15). Under the action of the synchronization mechanism, the auxiliary curtain (18) and the auxiliary curtain tube group rotate together with the main curtain (13). In terms of visual effect, the line grid (33) on the auxiliary curtain (18) moves together with the main curtain (13). After the backlight board (6) is lit, the line grid on the auxiliary curtain can be seen through the main curtain, which is convenient for teachers. When writing and teaching, under the guidance of the grid, the text or sentence can be written in a standardized and neat manner without bending or deflection. When the writing area is full, the tooth (22) is turned to turn the main curtain (13) upward, and the auxiliary curtain (18) and the grid (33) move upward accordingly, and the written content is moved to the top of the whiteboard or the rotating part (14) or the back of the main curtain (34). At this time, the area at the backlight board (6) is a new writing area, and writing can continue. After writing is completed, the backlight board (6) is turned off, and the guide grid (33) is no longer visible on the main curtain (13), so that the written content on the main curtain (13) is clean and clear.

2. The rolling blackboard for teaching blackboard writing according to claim 1 is characterized in that: The main curtain (13) is a semi-transparent, frosted, dark grey or dark green plastic curtain, in which a plurality of transparent fibers are embedded to enhance the strength of the main curtain (13) and prevent the main curtain (13) from deforming when being pulled or in high temperature seasons. The material of the auxiliary curtain (18) is the same as that of the main curtain (13), and is colorless and fully transparent.

3. The rolling blackboard for teaching blackboard writing according to claim 1 is characterized in that: The main curtain tube group and the auxiliary curtain tube group are made of aluminum alloy with a wall thickness of 1.5-2.0 mm. The damper (25) is a felt with a phosphor bronze spring to ensure the stability of operation, slow down the rotation speed of the shaft, and avoid the rebound of the rolling curtain. The glass plate (17) is a high-strength thin tempered glass with a wall thickness of 2.0-2.2 mm to ensure the flatness of the writing area and reduce the external force on the backlight plate (6) to prevent the backlight plate (6) from being worn when the auxiliary curtain (18) is rolled, or when writing, the backlight plate (6), the main curtain (13) and the auxiliary curtain (18) are deflated by the writing pen. The LED is white and bright, and the brightness is adjustable.

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