CN108973443A - A kind of cyclic switching formula blackboard convenient for erasing - Google Patents
A kind of cyclic switching formula blackboard convenient for erasing Download PDFInfo
- Publication number
- CN108973443A CN108973443A CN201810907966.1A CN201810907966A CN108973443A CN 108973443 A CN108973443 A CN 108973443A CN 201810907966 A CN201810907966 A CN 201810907966A CN 108973443 A CN108973443 A CN 108973443A
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- CN
- China
- Prior art keywords
- blackboard
- annular
- shaft
- rotating shaft
- suspension
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B43—WRITING OR DRAWING IMPLEMENTS; BUREAU ACCESSORIES
- B43L—ARTICLES FOR WRITING OR DRAWING UPON; WRITING OR DRAWING AIDS; ACCESSORIES FOR WRITING OR DRAWING
- B43L1/00—Repeatedly-usable boards or tablets for writing or drawing
- B43L1/04—Blackboards
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B43—WRITING OR DRAWING IMPLEMENTS; BUREAU ACCESSORIES
- B43L—ARTICLES FOR WRITING OR DRAWING UPON; WRITING OR DRAWING AIDS; ACCESSORIES FOR WRITING OR DRAWING
- B43L21/00—Blackboard or slate cleaning devices
Abstract
The present invention relates to a kind of cyclic switching formula blackboards convenient for erasing, including suspension and two pieces of blackboards, there are first rotating shaft and the second shaft arranged side by side up and down on blackboard, be respectively placed on suspension blackboard on both sides and with the matched two first annular slots of first rotating shaft, the both ends of first rotating shaft are respectively placed in two first annular slots；Be respectively placed on suspension blackboard on both sides and with matched two the second annular grooves of the second shaft, the both ends of the second shaft are respectively placed in two the second annular grooves；The top juxtaposition of the lower part of first annular slot and the second annular groove；The both ends of second shaft are respectively installed with the change being placed in the second annular groove, have on suspension and the matched annular recessing groove of change, two changes are respectively placed in the equal drawstring of two segment length at left and right sides of change and are connected, and drawstring is placed in annular recessing groove and in tension；Roller equipped with the multiple one-directional rotations being vertically distributed for being placed in blackboard side on blackboard is wiped.
Description
Technical field
The present invention relates to educational aid technical field, especially a kind of cyclic switching formula blackboard convenient for erasing.
Background technique
Blackboard transmits carrier as the main information in teaching process, is still widely used at present by each educational institution,
Convenient and fast Reusability function meets the interactive teaching and learning of presentation or not timing at any time of the content of courses in daily teaching very much.But
It is that existing blackboard needs little by little to wipe using blackboard eraser after writing, and blackboard area is usually larger, and erase process is time-consuming
Arduously, frequent write can make academics and students consume excessive physical strength with erasing, and occupy the more classroom instruction time.
In addition, it is contemplated that some complex contents are imparted knowledge to students when such as high number, physics, also to retain one always in erase process
A little figures or formula, in order to do in imparting knowledge to students in next step explanation with reference to or take notes convenient for student, but a large amount of books can be occupied in this way
Space is write, erasing times are further increased；In order to solve this problem, some blackboards use two pieces of blackboard slide handovers
Structure allows and the content retained is needed to be shown on one piece of blackboard always for use as reference or taken down notes convenient for student, but still
It can not solve the problems, such as frequently to wipe and erase process is time-consuming and laborious, thus, on the basis of guaranteeing existing blackboard function, increase
Function is quickly and easily wiped, the waste of unnecessary physical strength and energy in teaching process can be greatly mitigated.
Summary of the invention
For above situation, to make up technical deficiency present in the prior art, the present invention provides a kind of convenient for erasing
Cyclic switching formula blackboard, it is time-consuming and laborious during existing blackboard is wiped to solve the problems, such as.
Its technical solution solved is: the blackboard of suspension and the setting of two pieces of longitudinal perpendiculars including longitudinal perpendicular setting, institute
Equipped with setting before and after axis and first rotating shaft arranged side by side up and down and the second shaft on the blackboard stated, the diameter of first rotating shaft is greater than the
The diameter of two shafts, the length of the length of first rotating shaft less than the second shaft；It is respectively placed on the suspension before and after blackboard
Two sides and with the matched two first annular slots of first rotating shaft, the both ends of first rotating shaft are respectively slidably placed in two the first rings
In shape slot, first rotating shaft is done along first annular slot and back-shaped reciprocatingly slide and blackboard is driven to move；Have on the suspension and sets respectively
In blackboard front and rear sides and with matched two the second annular grooves of the second shaft, the both ends of the second shaft are respectively slidably placed in
In two the second annular grooves, the second shaft is done along the second annular groove and back-shaped reciprocatingly slide and blackboard is driven to move；Described first
Annular groove and the second annular groove are smoothly connected by two arc grooves opposing upper and lower through two sections of vertically arranged straight troughs respectively to be constituted,
For the depth of first annular slot less than the depth of the second annular groove, the top of the lower part of first annular slot and the second annular groove intersects weight
It is folded；The both ends of second shaft are respectively installed with the change being placed in the second annular groove, have on suspension and match simultaneously with change
With the consistent annular recessing groove in the second annular groove path, it is equal that two changes are respectively placed in two segment length at left and right sides of change
Drawstring be connected, drawstring is placed in annular recessing groove and in tension, and annular recessing groove plays guidance supporting role to drawstring；
Equipped with the roller wiping for being placed in the i.e. multiple one-directional rotations of back side being vertically distributed on the left of blackboard on the blackboard, the axis edge that roller is wiped
The length that front-rear direction setting and roller are wiped is matched with the front and rear width of blackboard.
Structure of the invention is accurate, easy to operate, so that two blackboards is carried out front and back, upper and lower position switching, may be used also
Realize mutual erasing between the two, the two is interrelated, supports one another, and effectively improves time-consuming during existing blackboard is wiped
Laborious problem.
Detailed description of the invention
Fig. 1 is main view of the invention.
Fig. 2 is A-A cross-sectional view of the invention.
Fig. 3 is B-B cross-sectional view of the invention.
Fig. 4 is isometric cutaway view of the invention.
Fig. 5 is the enlarged drawing of C portion in Fig. 4 of the invention.
Fig. 6 is the main view of suspension in the present invention.
Fig. 7 is the axonometric drawing of suspension in the present invention.
Specific embodiment
Below in conjunction with attached drawing, specific embodiments of the present invention will be described in further detail.
It is provided by Fig. 1 to Fig. 7, the present invention includes the suspension 1 of longitudinal perpendicular setting and the blackboard of two pieces of longitudinal perpendiculars setting
2, equipped with setting before and after axis and first rotating shaft 3 arranged side by side up and down and the second shaft 4 on the blackboard 2, first rotating shaft 3 it is straight
Diameter is greater than the diameter of the second shaft 4, the length of the length of first rotating shaft 3 less than the second shaft 4；There is difference on the suspension 1
Be placed in 2 front and rear sides of blackboard and with 3 matched two first annular slots 5 of first rotating shaft, the both ends of first rotating shaft 3 are respectively slidably
Ground is placed in two first annular slots 5, and first rotating shaft 3 is done along first annular slot 5 and back-shaped reciprocatingly slide and blackboard 2 is driven to move；
Be respectively placed on the suspension 12 front and rear sides of blackboard and with matched two the second annular grooves 6 of the second shaft 4, second turn
The both ends of axis 4 are respectively slidably placed in two the second annular grooves 6, and the second shaft 4 does back-shaped reciprocal cunning along the second annular groove 6
It moves and blackboard 2 is driven to move；The first annular slot 5 and the second annular groove 6 is passed through by two arc grooves opposing upper and lower respectively
Two sections of vertically arranged straight troughs are smoothly connected composition, depth of the depth less than the second annular groove 6 of first annular slot 5, the first ring
The top juxtaposition of the lower part of shape slot 5 and the second annular groove 6；The both ends of second shaft 4, which are respectively installed with, is placed in
Change 7 in second ring slot 6, have on suspension 1 matched with change 7 and with the consistent annular recessing groove 8 in 6 path of the second annular groove,
The equal drawstring 9 of two segment length of two changes 7 through being respectively placed in 7 left and right sides of change is connected, and drawstring 9 is placed in annular resigning
It in slot 8 and is in tension, annular recessing groove 8 plays guidance supporting role to drawstring 9, another when any one blackboard 2 is mobile
A blackboard 2 also moves under the pulling of drawstring 9；Since the distance between axles d between two shafts is remained unchanged, so it is both real
Existing blackboard 2 remains that upright state realizes that two shafts are respectively in two annular grooves while continuous clockwise or counterclockwise again
Sliding, then:
A) it is d1=d2 that the vertical straight segment length of two annular grooves described in is necessarily equal, and the segment length is equal to first rotating shaft
3 and the second the sum of distance between axles d and the length d △ of the equitant vertical flat segments of two annular grooves between shaft 4, i.e. d1=d2=
D+d △ (△ >=0 d)；
B) it is w1=w2 that the left and right width of the center line of two annular grooves described in is necessarily equal.
Generate collision when two blackboards 2 are mobile simultaneously in order to prevent, the first rotating shaft 3 and 2 upper surface of blackboard away from
It is equitant no more than two annular grooves from the sum of d3 and the distance between the second shaft 4 and 2 lower end surface of blackboard d4 vertical straight
Length d △, that is, d3+d4≤d △ of section.
10 are wiped equipped with the roller for being placed in the i.e. multiple one-directional rotations of back side being vertically distributed on the left of blackboard 2 on the blackboard 2,
The axis that roller wipes 10 be arranged along the longitudinal direction and the length of roller wiping 10 is matched with the front and rear width of blackboard 2, in order to once will be black
The erasing completely of plate 2 is clean.
It is placed on the left of blackboard 2 before and after the i.e. multiple axis of back side being vertically distributed preferably, being equipped on the blackboard 2
The roll shaft 11 of setting is connected with roller through isolator 12 such as unilateral bearing, ratchet and pawl arrangement on roll shaft 11 and wipes 10.
Preferably, there is the resilient key for being placed in 3 end of first rotating shaft in the first rotating shaft 3, the resilient key includes
Shank 13 and spring 14, under the elastic force effect of spring 14, shank 13 along first rotating shaft 3 axis to the end of first rotating shaft 3
Outer Slideslip makes a part of shank 13 be placed in the outside of first rotating shaft 3；The slot bottom of the first annular slot 5 has along the first ring
At least a pair of adjacent hemisphere 15 two-by-two of the circular path distribution of shape slot 5, the distance between two hemisphere 15 and shank 13
Diameter is equal；After resilient key moves under external force with blackboard 2 to be contacted with hemisphere 15, resistance of the shank 13 by hemisphere 15
It keeps off and bounces back, after shank 13 pops up between two adjacent hemisphere 15, the barrier force of hemisphere 15 can overcome the gravity of blackboard 2
Being maintained at blackboard 2 when not by external force, current location is motionless, in order to the writing and displaying of the content of courses.
Preferably, the blackboard 2 includes framework 16 and the cover board 17 that is overlying on 16 right side of framework, described first
Shaft 3 and the second shaft 4 are placed in framework 16, and the roller wipes 10 left sides for being placed in framework 16.
Two pieces of blackboards 2 are loaded on suspension 1 by the present invention in use, pressing above embodiment, what selection was write
One blackboard 2, is pulled downward on, since change 7 and two sections of drawstrings 9 link together the second shaft 4 on two blackboards 2
And the equal length of two sections of drawstrings 9, therefore, when any blackboard 2 moves, another blackboard 2 is inevitable to do contrary movement simultaneously,
Therefore any blackboard 2, when being pulled to the lower part of suspension 1, another blackboard 2 is moved to 1 top of suspension, uses two pieces of blackboards 2 simultaneously
In the different content of courses of displaying；And at least one corresponding resilient key of blackboard 2 is placed between two adjacent hemisphere 15 at this time
Fix the vertical position of the blackboard 2, therefore two pieces of blackboards 2 will not generate position movement after external force removal.
Since two annular grooves are closed loop configuration, therefore it is suitable simultaneously two pieces of blackboards 2 can be made to realize according to above-mentioned implementation method
Hour hands or continuous movement counterclockwise, therefore, when needing to wipe the content on one of blackboard 2, continuous moving
The blackboard 2 of needs erasing makes itself and another 2 conversion levels position of blackboard, when the blackboard 2 that needs are wiped is placed in another blackboard 2
After back side corresponds to the left side in attached drawing 1, move up and down another blackboard 2, roller corresponding to another blackboard 2 wipe 10 with need to wipe
The plate face of the blackboard 2 removed generates contact, and since roller wipes 10 as one-directional rotation structure, therefore another blackboard 2 moves up and down a week
Phase, roller wipes 10, and only once, another time is frictional rolling contact for erasing；10 are wiped due to roller and is different from existing blackboard eraser, by right
The length setting that roller wipes 10 may be implemented disposably to wipe blackboard 2 completely completely, and erase process is simple and quick, and need not consume
Cross many-body force；In addition, when the unidirectional erasing function that roller wipes 10 can also guarantee not need erasing to the content on any blackboard 2 into
Row retains.
It is to sum up not difficult to obtain, 10 unidirectional erasing function is wiped using roller, can be suitble to according to actual needs selection blackboard 2
Moving direction realize erasing operation or content reservation operations, it is suitable for following a variety of actual use demands:
A) content on any blackboard 2 is quickly wiped；
B) retain the content on any blackboard 2 and the content on another blackboard 2 is quickly wiped；
C) retain simultaneously the content on two pieces of blackboards 2 and on demand transformation the two upper and lower position in order to on any blackboard 2
Appearance is modified at any time.
As it can be seen that two blackboards can be carried out front and back by the present invention, upper and lower position switches, and realize mutual wiping between the two
It removes, when being imparted knowledge to students using the present invention, the quick erasing to any blackboard can be not only realized by shirtsleeve operation, saves people
Power and time can also be achieved in the case where the content on any blackboard is not wiped free of, to another blackboard at any time carry out write or
Content modification effectively improves time-consuming and laborious during existing blackboard is wiped on the basis of retaining existing blackboard repertoire
Problem.
Claims (4)
1. a kind of cyclic switching formula blackboard convenient for erasing, including suspension (1) and it is parallel to two pieces of blackboards (2) of suspension (1),
It is characterized in that, equipped with being parallel to blackboard (2) horizontal length direction and arranged side by side along blackboard (2) short transverse on the blackboard (2)
The first rotating shaft (3) and the second shaft (4) of setting, the diameter of first rotating shaft (3) are greater than the diameter of the second shaft (4), and first turn
Length of the length of axis (3) less than the second shaft (4)；(2) two horizontal ends of blackboard are respectively placed on the suspension (1)
Outside and with first rotating shaft (3) matched two first annular slots (5), the both ends of first rotating shaft (3) are respectively placed in two first
In annular groove (5)；Be respectively placed on the suspension (1) on the outside of (2) two horizontal ends of blackboard and with the second shaft (4)
Two the second annular grooves (6) matched, the both ends of the second shaft (4) are respectively placed in two the second annular grooves (6)；Described first
Depth of the depth of annular groove (5) less than the second annular groove (6), a part and the second annular groove (6) of first annular slot (5)
A part of juxtaposition；The both ends of second shaft (4) are respectively installed with the change (7) being placed in the second annular groove (6),
Have on suspension (1) and is respectively placed in change (7) axis two sides with change (7) matched annular recessing groove (8), two changes (7)
The equal drawstring (9) of two segment length be connected, drawstring (9) is placed in annular recessing groove (8) and in tension；Described is black
Roller equipped with the multiple one-directional rotations along the distribution of blackboard (2) short transverse for being placed in blackboard (2) back side on plate (2) wipes (10).
2. a kind of reciprocal suitching type according to claim 1 is from erasing blackboard, which is characterized in that equipped with setting on blackboard (2)
It is unidirectional in being passed through on the multiple roll shafts (11) for being parallel to blackboard (2) length direction being vertically distributed of blackboard (2) back side, roll shaft (11)
Device (12) is connected with roller and wipes (10).
3. a kind of cyclic switching formula blackboard convenient for erasing according to claim 1, which is characterized in that first rotating shaft (3)
On have the resilient key for being placed in first rotating shaft (3) end, the resilient key includes shank (13) and spring (14), in spring (14)
Elastic force effect under, shank (13) along first rotating shaft (3) axis to outside the end of first rotating shaft (3) Slideslip make shank (13)
A part is placed in the outside of first rotating shaft (3)；The slot bottom of the first annular slot (5) has the annular along first annular slot (5)
The hemisphere (15) adjacent two-by-two of path profile；It is connect when resilient key moves under external force with blackboard (2) with hemisphere (15)
After touch, shank (13) by hemisphere (15) blocking and bounce back, when shank (13) pops up between two adjacent hemisphere (15)
Afterwards, the barrier force of hemisphere (15) can overcome the gravity of blackboard (2) that blackboard (2) is made to be maintained at current location not when not by external force
It is dynamic.
4. requiring a kind of cyclic switching formula blackboard convenient for erasing according to right 1, which is characterized in that blackboard (2) includes
Framework (16) and the cover board (17) for being overlying on framework (16) side, the first rotating shaft (3) and the second shaft (4) are placed in framework
(16) on, the roller wipes the other side that (10) are placed in framework (16).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810907966.1A CN108973443A (en) | 2018-08-10 | 2018-08-10 | A kind of cyclic switching formula blackboard convenient for erasing |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810907966.1A CN108973443A (en) | 2018-08-10 | 2018-08-10 | A kind of cyclic switching formula blackboard convenient for erasing |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN108973443A true CN108973443A (en) | 2018-12-11 |
Family
ID=64554276
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810907966.1A Pending CN108973443A (en) | 2018-08-10 | 2018-08-10 | A kind of cyclic switching formula blackboard convenient for erasing |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108973443A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112248688A (en) * | 2020-10-30 | 2021-01-22 | 李静 | Automatic cleaning blackboard |
| CN114801554A (en) * | 2022-05-18 | 2022-07-29 | 吉安职业技术学院 | Public multi-functional teaching device of english |
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| CN206841029U (en) * | 2017-03-24 | 2018-01-05 | 西南石油大学 | A kind of New Rotary Automatic erasing blackboard |
| CN207327924U (en) * | 2017-03-23 | 2018-05-08 | 上海理工大学 | A kind of blackboard device |
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| CN2176262Y (en) * | 1993-11-03 | 1994-09-07 | 洪建信 | Automatic dust-removing blackboard eraser |
| JPH11301178A (en) * | 1998-04-21 | 1999-11-02 | Takao Hashimoto | Running device for self-running type blackboard erasing machine |
| CN101168338A (en) * | 2006-10-25 | 2008-04-30 | 郭佳松 | Lamination blackboard |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112248688A (en) * | 2020-10-30 | 2021-01-22 | 李静 | Automatic cleaning blackboard |
| CN114801554A (en) * | 2022-05-18 | 2022-07-29 | 吉安职业技术学院 | Public multi-functional teaching device of english |
| CN114801554B (en) * | 2022-05-18 | 2023-01-17 | 吉安职业技术学院 | Public multi-functional teaching device of english |
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Application publication date: 20181211 |