US673254A - Blackboard-eraser. - Google Patents

Description

No. 673,254. Patented Apr. 30, 190i.

DE WAYNE GREENWOOD.

BLACKBOARD ERASEB.

(Application filed Dec. 4, 1900.) (No Model.)

M Z/MWW we Nomus PETERS 00.. PHOYO-IJYHCL, WASNINGYON, o. c,

UNITED STATES PATENT OFFICE.

DE WAYNE GREENWOOD, OF GIRARD, OHIO.

BLACKBOARD-ERASER.

SPECIFICATION forming part of Letters Patent No. 673,254, dated April 30, 1901.

Application filed December 4, 1900. Serial No. 38,657. (No model.)

To all whom it may concern.-

Be it known that I,DE WAYNE GREENWOOD,

a citizen of the United States, residing at Girard, in the county of Trumbull and State of Ohio, have invented certain new and useful Improvements in Blackboard-Erasers; and I hereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings.

My invention relates to blackboard erasers or rubbers, and has for its object the production of an eraser of improved construction and increased efficiency as compared with other appliances for the same or similar purposes heretofore invented or produced.

The invention resides, primarily, in the employment of a continuous strip of felt or other suitable fibrous material and its peculiar arrangement upon the working face of an eraserblock, whereby the method of construction is greatly facilitated, superior cutting action or erasing qualities obtained, and its durability insured.

The invention will be hereinafter described, and particularly pointed out in the claims.

In the accompanying drawings, which form part of this specification, and whereoncorresponding letters of reference indicate the same parts in the several views, Figure 1 represents a top plan view of the invention; Fig. 2, the same in side elevation; Fig. 3, an in verted plan showing clearly the novel continuous arrangement of the erasing material, together with adjacent dust-pockets; and Fig. 4 is an end view of the invention.

Reference being had to the drawings and letters thereon, A indicates an eraser block or body of ordinary construction, which for economy is preferably made of wood, though obviously the material may be varied indefinitely, as also its shape, provided only that a plane working or under surface B is maintained for reception of the erasing material.

Upon the surface B of block A is firmly secured, as by glue, a continuous strip of felt or other fibrous material 0, which has its beginning at a and after surrounding the outer edge of surface B to form a border doubles upon itself, as at 1). Continuing thence said strip 0 traverses the entire length of surface B within the border aforesaid by a series of recurrent folds 0, arranged at an angle to the longitudinal center of the figure and terminating in a double or reinforced end 'd, opposite to and for like purposes as that marked 17. Between the various folds or overlapping portions of said felt or fabric strip are formed dust-pockets D, the purpose and effect whereof is to gather chalk-dust when the eraser is in use. With this peculiar and novel arrangement of the felt strip it will be particularly noted that the folds 0 always present a shearing-surface to the chalk-lines upon a board, regardless of which may be the advance end of the eraser when in use. Pockets D, adjacent to such folds c, effectually gather all dust thus cut by said shearing action from surface of the blackboard, preventing the evil consequences of its dissemination throughout a room in which used. Furthermore, itwill be observed there are no exposed ends of the felt strip to fray or to become loosened by action of the eraser, the extremities b d being folded in, as shown by Fig. 3, in a manner to protect them.

The manufacture of erasers in accordance with my present invention is best effected by first winding or folding the felt strip over short pins properly arranged and spaced upon a moldboard, then coating the under surface B of block A with glue, and finally lifting the entire felt strip from the pins aforesaid by applying thereto the adhesive under surface of block A.

, Having thus described my invention, its construction, and operation,what I now claim, and desire to secure by Letters Patent, is

1. In a blackboard-eraser the combination with a body-block, of a continuous strip of fibrous material arranged thereon in a series of recurrent folds crossing said block obliquely, and intermediate dust-pockets, substantially as described.

2. In a blackboard-eraser the combination with a body-block, of a continuous strip of fibrous material arranged obliquely thereon in a series of recurrent folds inclosed within a border having reinforced ends, and intermediate dust-pockets, substantially as described.

In testimony whereof I subscribe my signature in presence of two witnesses.

DE WAYNE GREENWOOD.

Witnesses:

WIOK TAYLER, MARTHA OANFIELD.

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