JPH06239096A - Chalk dust removal device for blackboard - Google Patents

Abstract

PURPOSE:To improve environmental hygiene wherein a blackboard is used by connecting a vacuum vessel and blackboard eraser successively to a vacuum pump so as to provide communication therebetween and disposing a filter and valve therein to draw dusts of chalk under vacuum into the vacuum vessel, thereby preventing the dusts from scattering. CONSTITUTION:A vacuum vessel 6 is connected to a vacuum pump 8 through a hose 7 to establish communication therethrough and a blackboard eraser 1 is connected to the vessel 6 through a pipe 5 and hose 2 to provide communication therethrough. A chalk dust filter 4 is provided at a most suitable position for maintenance work between the vessel 6 and the eraser 1. Further a gate valve 3 is provided between the vessel 6 and the eraser 1 to open and close the communication therebetween. By the action of the pump 8, the interior of the vessel 6 is kept in a state of negative pressure and by opening the valve 3, dusts of chalk are drawn from the eraser 1 through the filter 4 into the vessel 6, whereby the dusts are prevented from scattering into the environment so that hygiene of the environment wherein blackboards are used can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is an optimum system for absorbing the dust of chalk scattered when using a blackboard which is frequently used in educational institutions such as schools and for maintaining the environmental hygiene of using the blackboard. Regarding

[0002]

2. Description of the Related Art A conventional blackboard eraser of this type is provided with a suction device such as a fan as disclosed in Japanese Patent Laid-Open No. 271000/1990 to suck in chalk dust.

[0003]

In the prior art, there was a problem that the dust of the choke could not always be efficiently sucked due to the suction fluctuation of the suction device, and the suction amount could not be large because the flow velocity was low.

[0004]

In order to achieve the above object, in the present invention, a vacuum pump, a vacuum container, a blackboard eraser communicating with the vacuum container, and a maintenance work are performed between the blackboard eraser and the vacuum container. A choke dust filter is installed at an optimum location, and a sluice valve that opens and closes between the vacuum container and the blackboard eraser is provided as appropriate.

[0005]

[Function] A vacuum container is kept in a negative pressure state by a vacuum pump. When erasing figures or letters written on the blackboard, open the sluice valve that opens and closes between the vacuum container and the blackboard eraser, and move the blackboard eraser in normal operation to erase the written matter. It is possible to prevent dust from scattering into the environment where the blackboard is used by sucking the dust from the chalk out by using the negative pressure of the vacuum container.

The pressure of the vacuum pump is 133 Pa (1 Torr)
Reducing below is relatively easy, which is an advantage. However, it is not easy to secure the air volume like a blower, which is a disadvantage. Therefore, a vacuum container is used to take advantage of the characteristics of the vacuum pump and to supplement the disadvantages.

A filter is installed so that the choke dust sucked into the vacuum container does not enter the vacuum container, and the filter is cleaned appropriately.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 shows a perspective view of an embodiment of the present invention.
Dust rises when the chalk is erased with the blackboard eraser, but the wiping operation is started and the solenoid valve is opened, and the dry vacuum pump of 8 communicates with the vacuum container of 6 which is in a negative pressure state in advance. Therefore, the chalk dust wiped off the blackboard surface at the blackboard erased part will pass through the 4 of 2 to 4
Captured by the filter.

The vacuum container is constantly evacuated by a vacuum pump to keep the internal pressure of the container at 1 Torr or less. The blackboard eraser has a structure as shown in Fig. 3 and has a dust suction port around the cloth.
If you want to erase what is written on the blackboard, press the blackboard eraser. The pressing operation opens the solenoid valve and connects it to a vacuum container whose pressure is 1 Torr or less. This makes it possible to obtain a pressure difference of 1 kg / cm ³ that cannot be obtained with a normal vortex blower or a blower for a cleaner, and the flow rate corresponding to the internal volume of the container.
The flow rate of dust is also obtained.

[0011]

According to the present invention, by utilizing the advantages of machines such as a vacuum pump, a blower, and a vortex blower, and by using a vacuum container together to make up for the disadvantages, the blackboard eraser can be efficiently sucked. It is possible to absorb the dust of chalk that is scattered when using the blackboard, and maintain the environmental health of using the blackboard.

[Brief description of drawings]

FIG. 1 is a perspective view of a conventional blackboard eraser.

FIG. 2 is a perspective view of an embodiment of the present invention.

FIG. 3 is a perspective view of the blackboard eraser of the present invention.

[Explanation of symbols]

1 ... Blackboard eraser with suction device, 3 ... Valve (for example, solenoid valve for vacuum), 4 ... Filter, 6 ... Vacuum container, 8 ... Dry vacuum pump.

Claims (1)

[Claims] 1. A vacuum pump, a vacuum container communicating with the vacuum pump, a blackboard eraser communicating with the vacuum container, and a maintenance work provided between the blackboard eraser and the vacuum container. A chalk dust removing device for a blackboard, wherein a chalk dust filter and a sluice valve that opens and closes between the vacuum container and the blackboard eraser are provided at a position.