CN203885068U - Rotatable angle-adjusting anti-reflective blackboard - Google Patents
Rotatable angle-adjusting anti-reflective blackboard Download PDFInfo
- Publication number
- CN203885068U CN203885068U CN201420243050.8U CN201420243050U CN203885068U CN 203885068 U CN203885068 U CN 203885068U CN 201420243050 U CN201420243050 U CN 201420243050U CN 203885068 U CN203885068 U CN 203885068U
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- gear
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- plate body
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Abstract
The utility model discloses a rotatable angle-adjusting anti-reflective blackboard comprising an inner frame, an outer frame, a blackboard body and an indexing and positioning mechanism. The blackboard body is arranged in the inner frame, and the inner frame is matched with the outer frame in arrangement in a manner of being capable of rotating around a vertical center line. On the basis that the advantages of various existing blackboards are guaranteed, the blackboard body can generate certain inclination by pushing the inner frame or the blackboard body to rotate around the self axis in actual teaching through simple modification, on the basis that the angles of view of main classroom positions are unaffected, reflection of the blackboard body under the conditions of the presence of sunlight or strong light and the like can be avoided reasonably, the requirements for the view angles of students on two sides of the classroom are met, and quick positioning can be realized after the blackboard body inclines due to the arranged indexing and positioning mechanism.
Description
Technical field
The utility model relates to a kind of teaching aid, particularly a kind of rotatable reflection prevention blackboard with adjusting angle.
Background technology
In field research, the existing blackboard using is owing to being fixed on body of wall, only the beholder over against blackboard just has good visual angle, the beholder who is positioned at both sides, classroom but may be because visual angle deflection or reflectively can not obtain good academic environment, cause the understanding of knowledge thoroughly not, the interactive enthusiasm of teachers and students reduces.
For addressing the above problem, someone has designed some reflection prevention blackboards, by installing reflector additional, or two plate bodys about arranging, the mode that two plate bodys can rotate around self side respectively reduces reflective, though there is certain effect, but DeGrain, use quite inconvenience, also it is reflective to prevent that someone has designed a kind of blackboard of adjustable tilt angle, though this blackboard tiltable, but owing to lacking quick positioning mechanism, use unstable, effect is not obvious equally, and the blackboard using in existing classroom mostly is type of push and pull up down blackboard, by chain drive, realize, as adopt above-mentioned existing mode, repacking cost is high, be unfavorable for popularizing.
Therefore, need to improve existing blackboard, can make blackboard prevent reflective, rationally utilize space, classroom, make classroom substantially not have the blind area to blackboard, rationally avoid part reflective, and, only need on the basis of existing blackboard, simply reequip, realize the rational utilization of resource.
Utility model content
In view of this, the utility model provides a kind of rotatable reflection prevention blackboard with adjusting angle, on the basis of existing various blackboard, simply reequip, can make blackboard body rotate, effectively prevent reflectively, rationally utilize space, classroom, make classroom substantially not have the blind area to blackboard, and can after blackboard body tilts, realize location fast, use simple and reliable.
Rotatable reflection prevention blackboard with adjusting angle of the present utility model, comprises inner frame, outside framework and blackboard body, and described blackboard body is arranged in inner frame, and described inner frame is equipped with mode and the described outside framework that can rotate around vertical center line;
Also comprise dividing and positioning mechanism, described dividing and positioning mechanism comprises arc strip and positioning component, described arc strip is arranged at outside framework inner side, described positioning component comprises spring and location spheroid, in the outside opening groove that described spring fitting arranges on inner frame, described arc strip inner side is upper has some location at spherical surface grooves along circumferential arrangement, and described spring forms location in corresponding location at spherical surface groove mode can described location spheroid being pressed on after inner frame rotates is connected with described location spheroid.
Further, also comprise projection screen and for projection screen and the synchronization-moving synchronous drive mechanism of projecting apparatus, described synchronous drive mechanism comprises chain wheel drive assembly and gear drive assembly;
Described chain wheel drive assembly comprises chain wheel set, chain and bevel gear I, chain wheel set comprises sprocket wheel I, sprocket wheel II, sprocket shaft I and sprocket shaft II, sprocket shaft I and sprocket shaft II are all set up in parallel in outside framework top in the mode that can rotate around self axis, sprocket shaft I and sprocket wheel I are in circumferencial direction secure fit, sprocket shaft II and sprocket wheel II are in circumferencial direction secure fit, described chain is fixedly connected with described projection screen upper end, and coordinate with described sprocket wheel I and the transmission of described sprocket wheel II, described bevel gear I is arranged at described sprocket shaft II leading section;
Described gear drive assembly comprises gear shaft, bevel gear II and bevel gear III, described gear shaft is arranging around the mode of self axis, described gear shaft at least comprises primary pinion axle and the final-stage gear axle that transmission coordinates, the axis of primary pinion axle is vertical in transverse plane with the axis of sprocket shaft II, bevel gear II be fixedly installed in a circumferential direction primary pinion axle and with bevel gear I conical surface engaged transmission, described final-stage gear axle axis is vertical in perpendicular with the installation shaft axis of projecting apparatus, bevel gear III is fixedly installed on final-stage gear axle in a circumferential direction, the bevel gear IV conical surface engaged transmission that bevel gear III and projecting apparatus installation shaft circumferencial direction are fixedly installed.
Further, described gear shaft also comprises intermediate gear shaft I and intermediate gear shaft II, primary pinion axle coordinates with the transmission of intermediate gear shaft I by gear pair I, intermediate gear shaft I coordinates by the transmission of gear pair II with intermediate gear shaft II, and intermediate gear shaft II coordinates by belt transmission with final-stage gear axle.
Further, described inner frame upper and lower side middle part is provided with runner assembly, and described runner assembly comprises rotating shaft and bearing, and rotating shaft is fixedly connected with inner frame and is rotatably assorted with outside framework.
Further, on described arc strip, between location at spherical surface groove, be also provided with between two location spheroid is rotated to the together mobile guide chute leading with inner frame.
Further, described blackboard body comprises plate body I and plate body II, and described plate body I and described plate body II shift to install, and described plate body I and described plate body II are all being equipped with along the mode vertically moving up and down and inner frame single-degree-of-freedom.
Further, described location at spherical surface groove arranges 5.
Further, described inner frame rotation angle of inclination is 0 °-15 °.
Further, the resultant gear ratio of described gear drive assembly is 1:8.
Further, on described inner frame, be also provided with for the push-and-pull assembly to blackboard body push-and-pull, described push-and-pull assembly comprises chain drive-belt and is arranged at the gear on inner frame in the mode that can rotate around self axis, chain drive-belt one end is fixedly connected with plate body I, the other end is walked around gear and is fixedly connected with plate body II, and on described inner frame, corresponding plate body I and plate body II are respectively provided with a moving track.。
The beneficial effects of the utility model: rotatable reflection prevention blackboard with adjusting angle of the present utility model, guaranteeing on the basis of existing various blackboard advantage, can pass through simple refit, can in field research, realize by promoting inner frame or blackboard body and rotate and make blackboard body produce certain effect tilting around self axis, do not affecting on the basis at main body classroom location visual angle, both can rationally avoid there be the reflective of blackboard body in the situations such as sunlight or light is strong, meet again both sides, classroom student's visual angle demand, simultaneously, also be provided with dividing and positioning mechanism, after tilting, blackboard body can realize quick location, the utility model structural design is simple, without complex parts, be easy to processing, cost is low, assembling capacity and manufacturability are all better, and simple to operation, not only can solve series of problems in teaching process, and on health without impact, environmentally safe, there is good general applicability and promotional value.
Accompanying drawing explanation
Below in conjunction with drawings and Examples, the utility model is further described.
Fig. 1 is the utility model structural representation;
Fig. 2 is Fig. 1 schematic top plan view;
Fig. 3 is that top view is looked on Fig. 1 right side.
The specific embodiment
Fig. 1 is the utility model structural representation, Fig. 2 is Fig. 1 schematic top plan view, Fig. 3 is that top view is looked on Fig. 1 right side, as shown in the figure: the rotatable reflection prevention blackboard with adjusting angle of the present embodiment, comprise inner frame 1, outside framework 2 and blackboard body, described blackboard body is arranged in inner frame 1, and described inner frame 1 is equipped with mode and the described outside framework 2 that can rotate around vertical center line;
Also comprise dividing and positioning mechanism, described dividing and positioning mechanism comprises arc strip 3 and positioning component, described arc strip 3 is arranged at outside framework 2 inner sides, described positioning component comprises spring 5 and location spheroid 6, described spring 5 is installed in the outside opening groove arranging on inner frame 1, described arc strip has some location at spherical surface grooves 4 along circumferential arrangement on 3 inner sides, and described spring 5 forms location in corresponding location at spherical surface groove mode can described location spheroid 6 being pressed on after inner frame 1 rotates is connected with described location spheroid 6, wherein, spring 5 has certain pretightning force, location spheroid 6 is formed along the outside pressure of open slot, make it can keep being pressed against on arc strip 3, in practice, between arc strip 3 and location spheroid 6, to there is certain coefficient of friction, this coefficient of friction will make to guarantee that positioning component slides stably in the location at spherical surface groove on arc strip 3 surfaces and guide groove, guarantee again to prevent from locating and between spheroid 6 and location at spherical surface groove, rub too small and can not reach and locate or the job requirement from skidding off in guide chute road, in addition, location at spherical surface groove also can be other structure certainly, as locating hole, and the aperture of locating hole is less than the diameter of location spheroid 6, in order to avoid dropping into, location spheroid 6 in locating hole, causes the phenomenon that is difficult to skid off,
The utility model in use, if blackboard need to be turned an angle, only need push away by suitable dynamics blackboard body plate face, if make it rotate certain angle, can allow the beholder on the right see, need to stand in the left side of blackboard, firmly the left side of blackboard body is pushed away inward, blackboard body will rotate certain angle, and vice versa.
In the present embodiment, also comprise projection screen 7 and for projection screen 7 and the synchronization-moving synchronous drive mechanism of projecting apparatus, described synchronous drive mechanism comprises chain wheel drive assembly and gear drive assembly;
Described chain wheel drive assembly comprises chain wheel set, chain 8 and bevel gear I 9, chain wheel set comprises sprocket wheel I 10, sprocket wheel II 11, sprocket shaft I 12 and sprocket shaft II 13, sprocket shaft I 12 and sprocket shaft II 13 are all set up in parallel in outside framework 2 tops in the mode that can rotate around self axis, sprocket shaft I 12 and sprocket wheel I 10 are in circumferencial direction secure fit, sprocket shaft II 13 and sprocket wheel II 11 are in circumferencial direction secure fit, described chain 8 is fixedly connected with described projection screen 7 upper ends, and coordinate with described sprocket wheel I 10 and described sprocket wheel II 11 transmissions, described bevel gear I 9 is arranged at described sprocket shaft II 13 leading sections,
Described gear drive assembly comprises gear shaft, bevel gear II 14 and bevel gear III 15, described gear shaft is arranging around the mode of self axis, described gear shaft at least comprises primary pinion axle 16 and the final-stage gear axle 17 that transmission coordinates, the axis of primary pinion axle 16 is vertical in transverse plane with the axis of sprocket shaft II 13, bevel gear II 14 be fixedly installed in a circumferential direction primary pinion axle 16 and with bevel gear I 9 conical surface engaged transmission, described final-stage gear axle 17 axis are vertical in perpendicular with installation shaft 19 axis of projecting apparatus, bevel gear III 15 is fixedly installed on final-stage gear axle 17 in a circumferential direction, bevel gear IV 18 conical surface engaged transmission that bevel gear III 15 and projecting apparatus installation shaft 19 circumferencial directions are fixedly installed,
In actual applications, blackboard is conventionally in conjunction with use of projector equipment, projector equipment generally includes projecting apparatus and projection screen 7, projection screen 7 mostly is white screen, in teaching process, projection screen 7 can block a part of blackboard, cause blackboard to reduce by write area, when projection screen 7 uses, can not be by projection screen 7 harvestings, can only repeatedly clean blackboard, otherwise, projector equipment will cut out, to use, be projected the screen 7 blackboard parts of blocking, when using projector equipment, again projecting apparatus and projection screen 7 are opened, but start and close projecting apparatus, all need to wait for a period of time, cause the waste of class period, for addressing this problem, be provided for projection screen 7 and the synchronization-moving synchronous drive mechanism of projecting apparatus, projection screen 7 upper ends and chain 8 are fixing, do not needing to use projecting apparatus, only need projection screen 7 be moved and move left and right a segment distance with hand, drive chain 8 motions, chain 8 drives chain wheel set, thereby ordering about gear drive assembly is delivered to transmission in the installation shaft of projecting apparatus, thereby make projecting apparatus synchronously turn to certain angle with projecting apparatus, not only can effectively prevent projector distortion, also can make projecting apparatus input image not be radiated at and be projected the screen 7 part blackboards that block, the blackboard that just projection screen 7 can be blocked uses, also avoided repeatedly opening simultaneously, close projecting apparatus, and the required time of folding and unfolding projection screen 7, in addition, projection screen 7 is set to white screen, can be as the screen of projecting apparatus, also can write with black watercolor pencil, reach the use of two aspects.
In the present embodiment, described gear shaft also comprises intermediate gear shaft I 20 and intermediate gear shaft II 21, primary pinion axle 16 coordinates with 20 transmissions of intermediate gear shaft I by gear pair I, intermediate gear shaft I 20 coordinates by the transmission of gear pair II with intermediate gear shaft II 21, and intermediate gear shaft II 21 coordinates by belt 22 transmissions with final-stage gear axle 17, as shown in the figure, gear pair I comprises that circumferencial direction is fixedly installed on the driving gear I 23 of primary pinion axle 16 and the driven gear I 24 that circumferencial direction is fixedly installed on intermediate gear shaft I 20, driving gear I 23 and driven gear I 24 engaged transmission, gear pair II comprises that circumferencial direction is fixedly installed on the driving gear II 25 of intermediate gear shaft I 20 and the driven gear II 26 that circumferencial direction is fixedly installed on intermediate gear shaft II 21, driving gear II 25 and driven gear II 26 engaged transmission, in intermediate gear shaft II 21, be along the circumferential direction also fixed with belt pulley I, on final-stage gear axle 17, be along the circumferential direction also fixed with belt pulley II, belt 22 is enclosed within belt pulley I and belt pulley II upper driving coordinates, increase Multi-stage transmission gear, guarantee compared with in the situation of high transmission ratio, reach the object that reduces gear size, mounting structure is compacter.
In the present embodiment, described inner frame 1 upper and lower side middle part is provided with runner assembly, and described runner assembly comprises rotating shaft 27 and bearing 28, and rotating shaft is fixedly connected with inner frame 1 and is rotatably assorted with outside framework 2.
In the present embodiment, on arc strip 3, between location at spherical surface groove, be also provided with between two location spheroid 6 is rotated to the together mobile guide chute leading with inner frame 1; Mobile formation guide effect to the location spheroid 6 of positioning component, prevents wrong sliding.
In the present embodiment, described blackboard body comprises plate body I 29 and plate body II 30, and described plate body I 29 and described plate body II 30 shift to install, and described plate body I 29 and described plate body II 30 are all being equipped with along the mode vertically moving up and down and inner frame 1 single-degree-of-freedom; On described inner frame 1, be also provided with for the push-and-pull assembly to blackboard body push-and-pull, described push-and-pull assembly comprises chain drive-belt 31 and is arranged at the gear 32 on inner frame 1 in the mode that can rotate around self axis, chain drive-belt 31 one end are fixedly connected with plate body I 29, the other end is walked around gear 32 and is fixedly connected with plate body II 30, and on described inner frame 1, corresponding plate body I 29 and plate body II 30 are respectively provided with a moving track.
In the present embodiment, described location at spherical surface groove arranges 5; There is good locating effect.
In the present embodiment, it is 0 °-15 ° that described inner frame 1 rotates angle of inclination; Guaranteeing on the basis at main body classroom location visual angle, both can rationally avoid there be the reflective of blackboard body in the situations such as sunlight or light is strong, meeting again both sides, classroom student's visual angle demand.
In the present embodiment, the resultant gear ratio of described gear drive assembly is 1:8; When projection screen 7 moves horizontally 300mm left and right, can make the corner of projecting apparatus is 90 °, has good coordination projection screen 7 and the synchronization-moving effect of projecting apparatus.
Finally explanation is, above embodiment is only unrestricted in order to the technical solution of the utility model to be described, although the utility model is had been described in detail with reference to preferred embodiment, those of ordinary skill in the art is to be understood that, can modify or be equal to replacement the technical solution of the utility model, and not departing from aim and the scope of technical solutions of the utility model, it all should be encompassed in the middle of claim scope of the present utility model.
Claims (10)
1. a rotatable reflection prevention blackboard with adjusting angle, is characterized in that: comprise inner frame, outside framework and blackboard body, described blackboard body is arranged in inner frame, and described inner frame is equipped with mode and the described outside framework that can rotate around vertical center line;
Also comprise dividing and positioning mechanism, described dividing and positioning mechanism comprises arc strip and positioning component, described arc strip is arranged at outside framework inner side, described positioning component comprises spring and location spheroid, in the outside opening groove that described spring fitting arranges on inner frame, described arc strip inner side is upper has some location at spherical surface grooves along circumferential arrangement, and described spring forms location in corresponding location at spherical surface groove mode can described location spheroid being pressed on after inner frame rotates is connected with described location spheroid.
2. rotatable reflection prevention blackboard with adjusting angle according to claim 1, is characterized in that: also comprise projection screen and for projection screen and the synchronization-moving synchronous drive mechanism of projecting apparatus, described synchronous drive mechanism comprises chain wheel drive assembly and gear drive assembly;
Described chain wheel drive assembly comprises chain wheel set, chain and bevel gear I, chain wheel set comprises sprocket wheel I, sprocket wheel II, sprocket shaft I and sprocket shaft II, sprocket shaft I and sprocket shaft II are all set up in parallel in outside framework top in the mode that can rotate around self axis, sprocket shaft I and sprocket wheel I are in circumferencial direction secure fit, sprocket shaft II and sprocket wheel II are in circumferencial direction secure fit, described chain is fixedly connected with described projection screen upper end, and coordinate with described sprocket wheel I and the transmission of described sprocket wheel II, described bevel gear I is arranged at described sprocket shaft II leading section;
Described gear drive assembly comprises gear shaft, bevel gear II and bevel gear III, described gear shaft is arranging around the mode of self axis, described gear shaft at least comprises primary pinion axle and the final-stage gear axle that transmission coordinates, the axis of primary pinion axle is vertical in transverse plane with the axis of sprocket shaft II, bevel gear II be fixedly installed in a circumferential direction primary pinion axle and with bevel gear I conical surface engaged transmission, described final-stage gear axle axis is vertical in perpendicular with the installation shaft axis of projecting apparatus, bevel gear III is fixedly installed on final-stage gear axle in a circumferential direction, the bevel gear IV conical surface engaged transmission that bevel gear III and projecting apparatus installation shaft circumferencial direction are fixedly installed.
3. rotatable reflection prevention blackboard with adjusting angle according to claim 2, it is characterized in that: described gear shaft also comprises intermediate gear shaft I and intermediate gear shaft II, primary pinion axle coordinates with the transmission of intermediate gear shaft I by gear pair I, intermediate gear shaft I coordinates by the transmission of gear pair II with intermediate gear shaft II, and intermediate gear shaft II coordinates by belt transmission with final-stage gear axle.
4. rotatable reflection prevention blackboard with adjusting angle according to claim 3, is characterized in that: described inner frame upper and lower side middle part is provided with runner assembly, and described runner assembly comprises rotating shaft and bearing, and rotating shaft is fixedly connected with inner frame and is rotatably assorted with outside framework.
5. rotatable reflection prevention blackboard with adjusting angle according to claim 4, is characterized in that: on described arc strip, be also provided with between two between location at spherical surface groove location spheroid is rotated to the together mobile guide chute leading with inner frame.
6. rotatable reflection prevention blackboard with adjusting angle according to claim 5, it is characterized in that: described blackboard body comprises plate body I and plate body II, described plate body I and described plate body II shift to install, and described plate body I and described plate body II are all being equipped with along the mode vertically moving up and down and inner frame single-degree-of-freedom.
7. rotatable reflection prevention blackboard with adjusting angle according to claim 6, is characterized in that: described location at spherical surface groove arranges 5.
8. rotatable reflection prevention blackboard with adjusting angle according to claim 7, is characterized in that: it is 0 °-15 ° that described inner frame rotates angle of inclination.
9. rotatable reflection prevention blackboard with adjusting angle according to claim 8, is characterized in that: the resultant gear ratio of described gear drive assembly is 1:8.
10. rotatable reflection prevention blackboard with adjusting angle according to claim 9, it is characterized in that: on described inner frame, be also provided with for the push-and-pull assembly to blackboard body push-and-pull, described push-and-pull assembly comprises chain drive-belt and is arranged at the gear on inner frame in the mode that can rotate around self axis, chain drive-belt one end is fixedly connected with plate body I, the other end is walked around gear and is fixedly connected with plate body II, and on described inner frame, corresponding plate body I and plate body II are respectively provided with a moving track.
Priority Applications (1)
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CN201420243050.8U CN203885068U (en) | 2014-05-13 | 2014-05-13 | Rotatable angle-adjusting anti-reflective blackboard |
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CN201420243050.8U CN203885068U (en) | 2014-05-13 | 2014-05-13 | Rotatable angle-adjusting anti-reflective blackboard |
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CN203885068U true CN203885068U (en) | 2014-10-22 |
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CN201420243050.8U Withdrawn - After Issue CN203885068U (en) | 2014-05-13 | 2014-05-13 | Rotatable angle-adjusting anti-reflective blackboard |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103919377A (en) * | 2014-05-13 | 2014-07-16 | 重庆交通大学 | Anti-reflection blackboard capable of adjusting angles in rotating mode |
-
2014
- 2014-05-13 CN CN201420243050.8U patent/CN203885068U/en not_active Withdrawn - After Issue
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103919377A (en) * | 2014-05-13 | 2014-07-16 | 重庆交通大学 | Anti-reflection blackboard capable of adjusting angles in rotating mode |
CN103919377B (en) * | 2014-05-13 | 2015-12-16 | 重庆交通大学 | Rotatable reflection prevention blackboard with adjusting angle |
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Legal Events
Date | Code | Title | Description |
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C14 | Grant of patent or utility model | ||
GR01 | Patent grant | ||
AV01 | Patent right actively abandoned |
Granted publication date: 20141022 Effective date of abandoning: 20151216 |
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C25 | Abandonment of patent right or utility model to avoid double patenting |