WO2004045782A2

WO2004045782A2 - An electromotive chalk eraser

Info

Publication number: WO2004045782A2
Application number: PCT/KR2003/000097
Authority: WO
Inventors: Keum Yun Seo
Original assignee: Smc Korea Co., Ltd
Priority date: 2002-11-19
Filing date: 2003-01-16
Publication date: 2004-06-03
Also published as: AU2003302032A1; KR20040043619A; WO2004045782A3; AU2003302032A8; CN1502481A

Abstract

The present invention relates to an electromotive chalk eraser which can prevent harmful influence of the chalk dust generated while erasing the blackboard on students and teachers. The electromotive chalk eraser of the present invention can easily and simply remove the adsorbed chalk dust therefrom to reduce the inconveniences caused in the course of re-using the chalk eraser, and it can be repeatedly used for a long time without being worn out, thus eliminating costs for exchanging old chalk erasers for new ones.

Description

AN ELECTROMOTIVE CHALK ERASER

FIELD OF THE INVENTION

The present invention relates to an electromotive chalk eraser for the removal of chalk dust on a blackboard, and more particularly, to an electromotive chalk eraser which can prevent harmful influence of the chalk dust generated while erasing the blackboard on students and teachers.

BACKGROUND OF THE INVENTION

Generally, a blackboard is a smooth, hard and dark- colored panel for writing on with chalk. Teachers teach their students by writing with chalk on the blackboard, and during the teaching hours they often have to erase their writings using a chalk eraser.

Conventional chalk eraser has on its bottom part a cloth of textile material including a wad of cotton therein to erase the chalk dust on the blackboard, and also has on its top a thick paper which is attached to the cloth of textile material .

The above conventional eraser has been widely used in schools and other educational institutions for a long time because it is light in weight and can be manufactured with low costs. However, it has disadvantages in that the chalk dust generated or produced while erasing the blackboard flies into the air and may cause health problems to students and teachers. Specifically, the chalk dust may stimulate a mucous membrane of a nose and can be very harmful to persons who are allergic or sensitive to the dust and may cause a respiratory disease if the chalk dust is inhaled with the air. In addition, in order to reuse the eraser after erasing the blackboard, it was often necessary to remove the chalk dust attached to and accumulated on the cloth of the eraser, which caused a lot of inconvenience to users and also may cause an adverse effect on users' respiratory organs and on environment.

Furthermore, if the eraser has been used repeatedly for a long time, the cloth of textile material at its bottom part and the thick paper on the top thereof become worn down, and thus the efficiency of erasing the blackboard remarkably deteriorates.

SUMMARY OF THE INVENTION

The object of the present invention is to provide an electromotive chalk eraser which adsorbs the chalk dust on a blackboard to minimize harmful influence by the chalk dust flying into the air on teachers and students .

Another object of the present invention is to provide an electromotive chalk eraser which can easily and simply remove the adsorbed chalk dust therefrom to reduce the inconveniences caused in the course of reusing the chalk eraser.

Another object of the present invention is to provide an electromotive chalk eraser which can be repeatedly used for a long time without being worn out and thus can eliminate costs for exchanging old chalk erasers for new ones .

To achieve the above objects, the electromotive chalk eraser according to the present invention comprises: an upper casing having an operating switch on its outside and a power supply in an inner space thereof; an intake motor associated with the power supply to rotate according to the operating switch; an impeller axially connected to the intake motor to rotate with the intake motor; a dust collector detachably mounted on one side of the upper casing and having an intake for the chalk dust on its lower part and a dust collecting chamber for containing the chalk dust therein; a check valve provided between the intake for the chalk dust and the dust collecting chamber; a lower casing coupled with the upper casing and including a receptacle in its inner space, an opening for adsorbing the chalk dust at the bottom thereof and an outlet on its upper part for discharging the chalk dust into the dust collector; a driving motor mounted to be driven in the receptacle; a sticking member mounted on both bottom ends of the lower casing; and a dust adsorbing member connected to the driving motor to adsorb the chalk dust on the blackboard, with a part of the periphery of the dust adsorbing member being protruded outside of the opening for adsorbing the chalk dust .

If the chalk eraser according to the present invention is switched on by the operating switch provided on the upper casing and is applied on a blackboard which is stained with the chalk dust, the sticking member of the eraser sticks on the blackboard and the dust adsorbing member is rotated to adsorb the chalk dust.

Then, the adsorbed chalk dust is moved to the outlet for discharging the chalk dust of the lower casing by the impeller connected to the intake motor and it is provided to the dust collector through the intake for the chalk dust. If the dust collector is filled with a certain amount of the chalk dust, it is easily removed from the upper casing, and the chalk dust is discharged outside. the eraser.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention, wherein:

Fig. 1 is a sectional view of the electromotive chalk eraser according to the present invention;

Fig. 2 is a side sectional view of Fig. 1 partially showing a state where the dust adsorbing member is connected to the driving motor; and

Fig. 3 is a plane view of the electromotive chalk eraser according to the present invention partially showing the sectional view of an upper casing of the eraser. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Detailed description of the present invention will be provided with reference to the accompanying drawings. The electromotive chalk eraser according to the present invention comprises an upper casing (10) having an operating switch (11) on its outside and a power supply (13) in an inner space (12) thereof; an intake motor (M) associated with the power supply (13) to rotate according to the operating switch

(11); an impeller (14) axially connected to the intake motor (M) to rotate with the intake motor (M) ; a dust collector (20) detachably mounted on one side of the upper casing (10) and having an intake for the chalk dust (22) on its lower part and a dust collecting chamber (21) for containing the chalk dust therein; a check valve (22a) provided between the intake for the chalk dust (22) and the dust collecting chamber (21) ; a lower casing (30) coupled with the upper casing

(10) and including a receptacle (31) in its inner space, an opening for adsorbing the chalk dust (32) at the bottom thereof and an outlet (33) on its upper part for discharging the chalk dust into the dust collector (20) ; a driving motor (M' ) mounted to be driven in the receptacle (31) ; a sticking member (34) mounted on both bottom ends of the lower casing (30) ; and a dust adsorbing member (40) connected to the driving motor (M' ) to adsorb the chalk dust on the blackboard, with a part of the periphery of the dust adsorbing member (40) being protruded outside of the opening for adsorbing the chalk dust (32) .

Fig. 1 is a sectional view of the electromotive chalk eraser (1) , wherein the dust adsorbing member (40) is provided in the lower casing (30) , and the impeller (14) is provided in the upper casing (10) to supply the chalk dust adsorbed by the dust adsorbing member (40) to the dust collector (20) . Also, the intake motor (M) is provided in the upper casing (10) to drive the impeller (14) and the dust adsorbing member (40) to rotate.

Fig. 2 is a side sectional view of the electromotive chalk eraser (1) of the present invention, partially showing the state where the dust adsorbing member (40) is connected to the driving motor (M' ) , and the driving motor (M' ) drives to rotate the dust adsorbing member (40) . Fig. 3 is a plane view showing the overall shape of the electromotive chalk eraser (1) and partially showing the sectional view of the upper casing (10) of the eraser, wherein the operating switch (11) is provided at one corner of the top of the upper casing (10) , and the impeller (14) and the intake motor (M) to rotate the impeller (14) are provided in the upper casing (10) . The lower casing (30) is provided below the upper casing (10) , and a driving switch (36) is provided at one corner of the top of the lower casing (30) to switch the dust adsorbing member (40) .

As shown in Figs. 1 and 3, the inner space (12) is formed in the upper casing (10), and the power supply (13) is provided in the inner space (12) to generate power.

As shown in Fig. 1, the power supply (13) comprises batteries to generate power. Besides the batteries, power can be supplied from the outside through electric wires.

That is, if a connection terminal is furnished on the wall of schools or educational institutions, the power can be supplied to the chalk eraser by connecting electric wires to the terminal. On the other hand, if a connection terminal is not provided or if the chalk eraser is to be used temporarily, batteries can be furnished with the upper casing (10) as the power supply

(13) .

On one side of the power supply (13) , the intake motor (M) is provided to be associated with the power supply (13) so that it can rotate according to ON/OFF operation of the operating switch (11) , and the impeller

(14) which is the fan type having multiple wings is axially connected to the intake motor (M) .

Further, in one part of the upper casing (10) , the dust collector (20) is provided to be detachably connected to the upper casing (10) , and it comprises the intake for the chalk dust (22) into which the chalk dust is input from the lower casing (30) and the dust collecting chamber (21) to contain the chalk dust collected from the lower casing (30) .

The check valve (22a) is provided between the intake for the chalk dust (22) and the dust collecting chamber (21) to supply the collected dust from the intake for the chalk dust (22) to the dust collecting chamber (21) .

In order to prevent the collected chalk dust in the dust collecting chamber (21) from being supplied to the impeller (14), a filter (23) having a filtering material (24) affixed thereto is provided between the dust collecting chamber (21) and the impeller (14) in the dust collecting chamber (21) , and an aperture (15) is provided between the filter (23) and the impeller (14) for the passage of the air exhausted from the dust collector (20) . Accordingly, the chalk dust and other impurities collected in the dust collector (20) are blocked by the filtering material (24) attached to the filter (23), and only the filtered pure air is discharged towards the inner space (12) of the upper casing (10) . The upper casing (10) is coupled with the lower casing (30) . The lower casing (30) comprises the receptacle (31) of a predetermined size, the opening for adsorbing the chalk dust (32) at the bottom part thereof and the outlet (33) for discharging the chalk dust into the dust collector (20) on its upper part.

Further, the sticking member (34) is provided on both bottom ends of the lower casing (30) to stick the eraser (1) onto the blackboard.

The sticking member can be made of various materials. Preferably, the sticking member is the cloth of textile material such as cotton flannel.

As shown in Fig. 2, coupling of the upper casing (10) with the lower casing (30) is achieved by engaging connectors (16) formed on both bottom ends of the upper casing (11) and curved outward with connectors (35) of the lower casing (30) which are formed on both upper ends of the lower casing (30) and curved inward to be engaged with the connectors (16) of the upper casing (10) . The lower casing (30) can be formed in one body with the receptacle (31) in its inner space or can be separated into an upper body and a lower body so that the respective receptacle (31) can be formed in their inner space . In the receptacle (31) of the lower casing (30) , the driving motor (M' ) is provided to rotate in association with the power supply (13) and it is connected to the dust adsorbing member (40) to adsorb and brush up the chalk dust on the blackboard. The dust adsorbing member (40) comprises a roller (40a) in the center thereof and a brush (40b) surrounding the roller (40a) and is connected to the driving motor (M' ) through a power transmission member (44) which comprises a belt and chains, so that the dust adsorbing member (40) can rotate in the same direction as the driving motor (M' ) .

More specifically, finishing members (42) having driving axes (41) in the center thereof are provided on both ends of the roller (40a) , and a pulley (43) is provided on the driving axis (41) . Another pulley (43) is also provided on the driving motor (M' ) , and the power transmission member (44) is provided on the pulleys.

Further, the finishing members (42) are fixed in the lower casing (30) through flanges (46) . The flange

(46) shown on the right side of Fig. 1 has elastic members (45) along its periphery. A plurality of bearings

(47) are provided between the flange (46) and the driving axis (41) so that the dust adsorbing member (40) can rotate along with the driving motor (M' ) .

The driving motor (M' ) which drives the dust adsorbing member (40) can be controlled by the operating switch (11) provided in the upper casing (10) . However, it is preferable that a separate driving switch (36) be provided in the lower casing (30) to control the driving motor (M' ) .

The driving switch (36) to control the driving motor (M' ) is connected to a substrate (36a) at one end of the upper plate of the lower casing (30) by a coupling means (37) which comprises bolts and screws. The substrate (36a) is associated with the power supply (13) . Depending on the amount of the chalk dust collected from the blackboard, it is possible to control the intake motor (M) and the driving motor (M' ) respectively. Thus, power from the power supply (13) can be used more efficiently.

If there is a large amount of chalk dust on the blackboard, the operating switch (11) in the upper casing (10) can be switched on, and if there is less amount of chalk dust on the blackboard, only the driving switch (36) can be switched on to erase the chalk dust. That is, the operating and driving switches (11 and 36) can be alternatively used as occasion demands, and thus the intake motor (M) and the driving motor (M' ) can be rotated by alternatively switching the switches (11 and 36) . In this manner, power can be efficiently saved.

If the rotating dust adsorbing member (40) is contacted on the surface of the blackboard, the chalk eraser becomes tightly adhered to the blackboard by the sticking member (34) provided on both bottom ends of the lower casing (30) , and the chalk dust on the blackboard is removed from the surface of the blackboard and adsorbed by the brush (40b) of the dust adsorbing member (40) .

The chalk dust adsorbed by the brush (40b) is carried by the rotation of the impeller (14) to the intake for the chalk dust (22) via the outlet for discharging the chalk dust (33) , and it is supplied to the dust collector (20) .

In the course of adsorption and transportation of the chalk dust, a backward flow of the chalk dust can be prevented by the check valve (22a) which is mounted on the intake for the chalk dust (22) .

The check valve (22a) is made of elastic synthetic resin and/or elastic rubber. In normal states, as shown in Fig. 1, the check valve (22a) closes the intake for the chalk dust (22) . However, if the impeller (14) is driven by switching on the operating switch (11) , the check valve (22a) is opened as shown with the ghost line in Fig. 1, and thus the chalk dust is transported into the dust collecting chamber (21) . If the impeller (14) is stopped by switching off the operating switch (11) , the check valve (22a) then closes the intake for the chalk dust (22) .

If a certain amount of the chalk dust is collected in the dust collecting chamber (21) , the dust collector (20) can be removed from the upper casing (10) , and the collected chalk dust in the dust collecting chamber (21) can be discarded to a garbage can, etc. Then, the dust collector (20) is re-installed on one side of the upper casing (10) of the chalk eraser (1) of the present invention and can be re-used. Therefore, the electromotive chalk eraser (1) of the present invention can provide students and teachers with pleasant and clean environment for education.

The present invention described as above provides following advantages and effects:

Firstly, the present invention can prevent the chalk dust from flying in the air and thus can minimize harmful influence on students and teachers.

Secondly, as the dust collector can be easily detached from the electromotive chalk eraser of the present invention and the collected chalk dust can be simply treated and removed, the inconveniences caused in the course of re-using the chalk eraser can considerably be reduced. Thirdly, as the intake motor and the driving motor can be separately controlled depending on the amount of the chalk dust, power can be efficiently used and saved.

Lastly, the electromotive chalk eraser of the present invention can be repeatedly used for a long time without being worn out and thus can eliminate costs for exchanging old chalk erasers for new ones.

Claims

What is claimed is:

1. An electromotive chalk eraser comprising: an upper casing having an operating switch on its outside and a power supply in an inner space thereof; an intake motor associated with the power supply to rotate according to the operating switch; an impeller axially connected to the intake motor to rotate with the intake motor; a dust collector detachably mounted on one side of the upper casing and having an intake for the chalk dust on its lower part and a dust collecting chamber for containing the chalk dust therein; a check valve provided between the intake for the chalk dust and the dust collecting chamber; a lower casing coupled with the upper casing and including a receptacle in its inner space, an opening for adsorbing the chalk dust at the bottom thereof and an outlet on its upper part for discharging the chalk dust into the dust collector; a driving motor mounted to be driven in the receptacle; a sticking member mounted on both bottom ends of the lower casing; and a dust adsorbing member connected to the driving motor to adsorb the chalk dust on the blackboard, with a part of the periphery of the dust adsorbing member being protruded outside of the opening for adsorbing the chalk dust .

2. The electromotive chalk eraser as claimed in claim 1 characterized in that a filter is provided in the dust collector to prevent the collected chalk dust in the dust collecting chamber from being supplied to the impeller.