Patent Application
20070044263
The present invention relates generally to chalkboard and marker board erasers, and specifically to a chalkboard and marker board eraser using microfiber material as a cleaning material.
Blackboard erasers are a common item of everyday life. There are few among us who, as elementary school students, have not undertaken the chores of assisting a teacher in cleaning a blackboard or cleaning blackboard erasers by banging them together in the school yard. As such, many of us remember problems attendant with using the common blackboard eraser.
The common blackboard eraser typically is made from laminated felt pads attached to a cardboard backing board, and with its use, three problems arise. The first is the chalk dust. The felt pads are normally made of nylon threads that do not hold much chalk dust, thereby chalk dust is released into the classrooms with use. A second problem is the construction of the eraser. The felt pads and backing used to secure the felt pads are often too thin causing a user to hold the eraser by the sides of the felt pads in order to clean a blackboard. Therefore, the user often gets chalk dust on his or her fingers just from using the eraser. The third problem is that of ghosts. Common chalkboard erasers do not clean the chalkboard sufficiently; a significant quantity of chalk dust remains after using the common eraser, and the common eraser does not completely erase the writing but often leaves a significant image of the erased writing (a ghost image) that may interfere with new writing.
Several improvements have been made to overcome the problem of chalk dust. Many of the improvements have taken the form of adding mechanical brushes or rollers to the eraser, or by adding bins or other devices to collect the dust. See U.S. Pat. No. 6,895,627 to Lin, U.S. Pat. No. 4,941,225 to Liao, U.S. Pat. No. 4,742,594 to Chen, U.S. Pat. No. 4,392,268 to Victor, and U.S. Pat. No. 4,080,683 to Chong. Other improvements have been made to overcome the problem of an eraser easier to use, the improvements included adding holders, handles, straps, and backing plates. See U.S. Pat. No. 5,365,631 to Emerick, U.S. Pat. No. 5,072,483 to Durand, and U.S. Pat. No. 4,543,680 to Vlahos. Still other improvements made to erasers for whiteboards include providing disposable cleaning surfaces. See U.S. Pat. No. 4,937,910 to Frazier and U.S. Application 2004/0205919 by Sims.
The common blackboard eraser comprises laminated felt pads made mostly of nylon threads. Other cleaning materials such as chamois and sponge can erase the blackboard cleaner than felt, but each alternate material has at least one disadvantage. Sponge has a short life expectancy, and the cleaning efficiency of chamois decreases rapidly with use and chamois is difficult to clean.
However, none of these improvements were widely adopted. The eraser of yesterday is the eraser of today.
In accordance with the invention, a microfiber chalkboard eraser is provided for use with chalkboards, marker boards, and other writing surfaces, wherein the erasing surface is a microfiber material. The microfiber chalkboard eraser comprises a rectangular central core of a resilient material, a microfiber cleaning sheet covering the central core, and a cap or holder securing the covering and the resilient core.
Objects of the invention are to provide a microfiber chalkboard eraser that can more completely clean the chalkboard, that can hold more chalk dust, that can remove chalk dust easier and faster, and that can clean the chalkboard more efficiently than the common chalkboard eraser.
Other objects of the invention include providing an easily replaceable cleaning surface that can be reused after being cleaned, and providing an eraser that has a finger cap or holder to keep the user's fingers free from chalk dust.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a unit of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.
In the drawings:
Referring now to
The central core 11 is covered by the microfiber cleaning sheet 13. Microfibers are small fibers having a dimension of about 0.01 to about 5 denier, typically about 0.1 to about 1.0 denier. Denier is a scale for the heaviness (largely related to thickness) of fibers in a fabric. The higher the denier, the thicker the fiber. The denier value is defined as the mass in grams per 9000 meters of yarn. Microfibers are typically made from two relatively incompatible polymer materials, for example, polyester and polyamide in a weight percentage ratio ranging from about 50/50 to about 90/10. The fibers are spun extruded and then split into microfilaments during manufacturing. The most common structure of the microfiber is a core structure with wedge shaped perimeter structures. The yarn made from the microfiber contains high surface area wedge shaped filaments and a core filament with furrows and channels. These furrows and channels help provide a capillary action, which draws the dust including chalk dust into the void spaces resulting in microfiber fabrics having much higher capacity of holding chalk dust than traditional cleaning material like nylon threads, sponge, and chamois. Since there can be about 180,000 microfibers per square inch, the soft fabric has a large surface area available for contact with chalk dust, thereby removing more chalk and chalk dust from blackboards than commonly used chalkboard erasers.
Referring now to
A first end cover panel 40 and a second end cover panel 44 are connected to the bottom cover panel 36 and the top cover panel 32 respectively at fold line 39 and 43. A third end cover panel 42 and a fourth end cover panel 46 are connected to the bottom cover panel 36 and the top cover panel 32 respectively at fold line 41 and 45.
The dimensions of the microfiber cleaning sheet 13 are such that when folded along the fold lines 31, 33, 35, 37, 39, 41, 43 and 45, the microfiber cleaning sheet 13 completely covers the central core 11. The microfiber cleaning sheet 13 may be secured using any convenient means, including hook and loop fasteners as shown in
The central core 11 is fully covered by the microfiber cleaning sheet 13 all side sides when the panel 34 is attached to the panel 38 and the panel 44 is attached to the panel 40 and the panel 46 is attached to the panel 42. The microfiber chalkboard eraser 10 is assembled when the central core fully covered by the microfiber cleaning sheet 13 is fitted in the holder 12 with panel 36 as the cleaning surface.
A second embodiment of the present invention is shown is
A fourth embodiment is shown in
As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalence of such metes and bounds are therefore intended to be embraced by the appended claims.
