KR20110006275A - Gear with the structure of a blackboard eraser - Google Patents

Abstract

PURPOSE: A blackboard eraser and a gear structure thereof are provided to minimize the floating of dust by using a clean cotton part in order to erase a blackboard. CONSTITUTION: A plurality of saw blades are formed in an outer circumference around a rotary shaft. A lower gear has a saw blade having a streamlined convex one side and a streamlined concave other side. A movable guide hole(4) is formed along a fixed shaft inside. At least two teeth(3) has a pitch less than the pitch of a lower gear in a direction contacting the lower gear. The side between the teeth includes an upper gear(1) having a streamlined concave side. When the lower gear is rotated around the rotary shaft, a rotational angle in a one direction should be greater than a rotational angle in an opposite direction.

Description

Gear structure and a blackboard eraser {Gear with the structure of a blackboard eraser}

The present invention relates to a gear structure and a blackboard eraser using the gear structure. More specifically, the present invention is equipped with a gear structure for varying the rotation angle in accordance with the rotation direction, and the part for cleaning the blackboard to cover the roller cylindrical cylindrical surface mounted on the rotating shaft and by wiping the blackboard while rotating the rotating shaft by the gear structure It's about a blackboard eraser that lets you always clean the board with a clean side.

Korean Utility Model Registration No. 20-0287566 (published Aug. 19, 2002) discloses a blackboard eraser that can be dusted indoors by fixing a cotton cloth ring on a number of rollers and attaching a brush to the lid. When the blackboard eraser is cleaned, the roller cleans the board in the opposite direction to the rotation axis, and when the dust is brushed off, the board eraser has to be distinguished from the operation of cleaning the board and the dusting off motion. Before the dust on the cotton swab was wiped off, the board was wiped with a cotton cloth with chalk dust, so the chalk dust on the cotton cloth was blown and the board could not be cleaned.

 The present invention has been made to solve the problems of the prior art as described above, the object of the present invention is to provide a gear structure that can vary the angle of rotation according to the direction of rotation. Another object of the present invention is to provide a blackboard eraser that can remove the dust of the blackboard with a clean surface at all times by applying the gear structure.

Another object of the present invention is to provide a blackboard eraser that can remove the dust attached while cleaning the blackboard automatically does not require a separate dust hair movement.

Gear structure according to an aspect of the present invention for solving the technical problem as described above, the lower gear formed with a plurality of teeth on the outer circumferential surface and a guide hole movable along a fixed axis therein is formed in the direction in contact with the lower gear And an upper gear having at least two teeth whose pitch is smaller than the pitch of the lower gear.

In another aspect of the present invention, the blackboard eraser according to the present invention is fixed to a rotating shaft installed between two side surfaces of the housing having one side open and at one side of the housing inside a lower gear having a plurality of teeth formed on an outer circumferential surface thereof. A guide hole is formed along the fixed fixing axis and the upper surface has at least two teeth whose pitch is smaller than the pitch of the lower gear in the direction of contact with the lower gear, and the board is cleaned through the open one surface. Characterized in that it comprises a blackboard holding portion installed around the axis of rotation so that

According to the gear structure and the blackboard eraser according to the present invention, since the blackboard is always erased with a clean cotton cloth while using the blackboard eraser, it is possible to minimize the blowing of dust while dusting the blackboard (95% or more) and to erase the blackboard cleanly. It does not need a separate duster to remove the chalk dust on the eraser, which is hygienic and convenient.

Gear structure according to an aspect of the present invention for solving the technical problem as described above, the lower gear formed with a plurality of teeth on the outer circumferential surface and a guide hole movable along a fixed axis therein is formed in the direction in contact with the lower gear And an upper gear having at least two teeth whose pitch is smaller than the pitch of the lower gear.

In another aspect of the present invention, the blackboard eraser according to the present invention is fixed to a rotating shaft installed between two side surfaces of the housing having one side open and at one side of the housing inside a lower gear having a plurality of teeth formed on an outer circumferential surface thereof. A guide hole is formed along the fixed fixing axis and the upper surface has at least two teeth whose pitch is smaller than the pitch of the lower gear in the direction of contact with the lower gear, and the board is cleaned through the open one surface. It characterized in that it comprises a blackboard holding portion which is installed around the axis of rotation.

The teeth of the lower gear and the teeth of the upper gear are preferably formed such that the rotation angle of the lower gear rotates in a specific direction along the central axis is greater than the rotation angle of rotation in the opposite direction of the specific direction. . In addition, one surface of each tooth of the lower gear is a streamlined convex surface, the other surface of each tooth is a streamlined concave surface, the surface between the two teeth of the upper gear is preferably a streamlined concave surface. The upper surface of the upper gear may further include an elastic pin for providing an elastic force to the upper gear. The blackboard eraser is connected to the blackboard holding part on the upper surface of the housing, and removes dust attached to the blackboard holding part as the blackboard holding part rotates, and an amount of the inside of the housing parallel to the rotating shaft. It is preferable to further include a dust removal passage in which dust collected by the blackboard holding part is collected and a dust collecting groove capable of flowing out dust collected in the dust removal passage to a side of the housing in which the dust removal passage is in contact. . In addition, it is preferable that a dust removing cylinder collecting dust discharged through the dust collecting groove is connected to a side surface of the housing in which the dust collecting groove is formed, and the dust removing cylinder is connected to the housing in a detachable structure. The configuration, operation, and other features of the present invention will be readily understood by the preferred embodiments of the present invention described below with reference to the accompanying drawings.

Figures 1a and 1b respectively show the shape of the upper gear and the lower gear according to an embodiment of the gear structure according to the present invention. The upper gear 1 has at least two teeth 3 formed in a direction in contact with the lower gear 5 and a guide hole formed so that the fixed shaft 2 is movable in the central portion of the upper gear 1. (4) is formed. The number of teeth 3 is preferably three. The guide hole 4 is a space in which the fixed shaft 2 can move left and right when the upper gear 1 is engaged with the lower gear 5 to be engaged. The lower gear 5 is circular having a plurality of teeth 7 formed on an outer circumferential surface thereof, and is rotatable about a central rotation shaft 6. As shown in Figure 1a and Figure 1b, the surface between the two teeth of the upper gear (1) was formed as a streamlined concave surface, one surface of each tooth of the lower gear (5) is a streamlined convex surface, The other surface of each tooth was formed in the streamlined concave surface. At this time, the pitch width which means the distance between two adjacent teeth of the lower gear 5 should be larger than the distance between two teeth adjacent to the upper gear 1. 2 to 6 are diagrams for describing an operation process of the lower gear 1 and the upper gear 5 shown in FIGS. 1A and 1B. When the upper gear 1 and the lower gear 5 are coupled as shown in FIG. 2, one tooth 14 of the lower gear 5 is attached to the left teeth 8 of the upper gear 1. The lower gear 5 is engaged with the lower gear 5 so that the lower gear 5 does not rotate clockwise in the drawing. At this time, the left end of the guide hole 12 of the upper gear 1 is in contact with the central axis 11 and the lower gear ( The other tooth 15 of 5) is located to the left of the middle tooth 9 of the upper gear.

In the state of FIG. 2, if the rotary shaft 6 of the lower gear 5 is continuously rotated counterclockwise, the state of FIG. 5 is finally reached via the states of FIG. 3 and FIG. The process is described in detail as follows. That is, when the lower gear 5 rotates counterclockwise in the state of FIG. 2 in which the lower gear 5 stops rotating in the clockwise direction, the number 15 teeth of the lower gear 5 are rotated. As shown in FIG. 4, 15 pushes the left tooth 8 of the upper gear to the left, and as shown in FIG. 4, the number 16 teeth 16 of the lower gear 5 are the upper gear ( The central shaft 11 moves to the right end of the guide hole 12 of the upper gear 1 while pushing the middle tooth 9 of 1) to the left, as shown in FIG. 5, the upper gear 1 The right tooth 10) and the 17th tooth 17 of the lower gear 5 mesh with each other and no longer rotate counterclockwise. 2 to 5, the elastic pin 13 positioned on the upper gear 1 serves to support the upper gear 1 so that it no longer rotates clockwise. In the state of FIG. 5, the lower gear 5 is no longer rotated counterclockwise, but can be rotated clockwise. That is, when the lower gear 5 is rotated in the clockwise direction on the ground, the elastic pin 13 pushes the upper gear 1 to the right, and the sixteenth tooth 16 of the lower gear 5 is the upper part. While the intermediate shaft 9 of the gear 1 is pushed to the right, the rotary shaft 11 moves to the left end of the guide hole 12 of the upper gear 1, and the left tooth of the upper gear 1 as shown in FIG. 6. (8) and the sprocket 15 of the lower gear mesh with each other and stop no longer rotating clockwise. When the lower gear 5 is rotated counterclockwise in the state of FIG. 6, the state of FIG. 5 is stopped through the states of FIGS. 3 and 4. As a result, FIGS. 2 to 5 show one cycle for rotating the lower gear 5 counterclockwise, and FIGS. 5 and 6 show one cycle for rotating the lower gear 5 clockwise. At this time, there is a difference between the number of teeth of the lower gear 5 when the lower gear 5 is rotated in the clockwise direction and when the lower gear 5 is rotated in the counterclockwise direction. Therefore, by repeating the operation of rotating the lower gear 5 clockwise and counterclockwise, one tooth of the lower gear 5 moves a constant angle in one direction (counterclockwise direction). By reversing the streamlined direction of the lower gear 5 and changing the direction of the upper gear 1, a rotating device moving in one direction can be obtained, and the number of teeth of the lower gear 5 is adjusted. 7 to 11 can be continuously rotated by a predetermined angle in one direction by using the gear structure according to the present invention as described above to continuously clean the dust of the blackboard with a new surface. It shows a blackboard eraser according to an embodiment of the present invention made possible. 7 is an external perspective view of the blackboard eraser according to an exemplary embodiment of the present invention, FIGS. 8 and 9 are cross-sectional views, and FIG. 10 is a detailed perspective view of the dust removal passage 25 installed inside the housing 19. 11 is a perspective view of the dust removal container 18 installed on the side of the housing 19.

7 to 9, the blackboard eraser includes a housing 19 having one surface open, a roller 21 and a roller 21 protruding from the open surface of the housing 19 and being rotatable about a rotation axis. 21 is attached to the periphery of the blackboard holding portion consisting of a cotton cloth 22 made of a material that can easily remove the blackboard dust, and the lower gear 26 fixed to one or both ends of the rotating shaft of the roller 21 With that inside

A guide hole movable along a fixed shaft (not shown) protruding from an inner side surface of the housing 19, and a pitch of the lower gear 26 in a direction in contact with the lower gear 26. An upper gear 30 having at least two teeth smaller than a pitch and a dust removal brush installed on the inner upper surface of the housing 19 to be in contact with the face cloth 22 to remove dust attached to the face cloth 22. (23), dust blocking films (24, 33) for blocking dust removed by the dust removal brush (23) from being reversed, and dust removed by the dust removal brush (23) are the housing (19). Dust removal passages 25 and 34 for guiding to be collected on both sides of the inside of the dust collector, and dust collecting grooves 35 for discharging dust collected in the dust removal passages 25 and 34 out of the housing 19. And 36 and detachable from the housing 19 on the outer side of the housing 19 It is coupled to the possible structure and is configured to include a dust removal tube (18) for accommodating the discharged dust from the dust-collecting groove (35, 36). Referring to the operation of the blackboard eraser according to an embodiment of the present invention as described above are as follows. When the lower gear 26 is fixed to one end or both ends of the rotating shaft 20 of the roller 21 and the upper gear 30 is installed to interlock with the lower gear 26 on the side of the housing 19 When the board eraser is pushed in the left direction (ie, the roller rotates counterclockwise), the roller 21 is fixed at a predetermined angle (360 ° / number of teeth of the lower gear) according to the number of teeth of the lower gear 26. ), The board can be cleaned by stopping, and when the board eraser is pushed to the right (roller rotates clockwise), as shown in FIG. 5, the lower gear 15 and the upper gear The board can be cleaned by rotating and stopping by the play distance of the left tooth (8). At this time, since the rotation angle is different according to the clockwise direction and the counterclockwise direction according to the operating principle of the gear structure according to the present invention, if the blackboard eraser is pushed from side to side to clean the blackboard, it is always possible to clean the blackboard with a new surface. The attached cotton cloth 22 rotates and rubs against the dust removing brush 23 while the dust removing passage 25 does not flow back by the dust blocking film 24 installed on the upper inside of the housing (19 of FIG. 7). , 34) and the chalk dust collected in the dust removal passages (25, 34) through the dust collecting grooves (35, 36) of the dust removing container (18) by shaking the blackboard eraser from side to side to clean the blackboard. Collected in the dust removal container 18. Since the dust removing cylinder 18 is designed to be detachable from the housing 19, the dust removing cylinder 18 can be easily removed from the housing 19 by removing the dust removing cylinder 18 from the housing 19. . It will be apparent to those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The above detailed description, therefore, is not to be taken in a limiting sense in all respects and should be considered as illustrative. The scope of the invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the invention are included in the scope of the invention.

1 upper gear '

 5 lower gear

19 housing

21 rollers

22 cotton cloth

Claims (1)

A plurality of teeth is formed on the outer circumferential surface rotating around the axis of rotation, one surface of each tooth is a streamlined convex surface and the other surface is formed of a lower gear consisting of a streamlined concave surface and a guide hole movable along the fixed axis therein. And at least two teeth of a pitch smaller than a pitch of the lower gear in a direction in contact with the lower gear, wherein a surface between the teeth includes an upper gear consisting of a streamlined concave surface, wherein the lower gear is the Gear structure characterized in that the rotation angle to rotate in a specific direction when rotating about the rotation axis is formed larger than the rotation angle to rotate in the opposite direction of the specific direction.

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