US428585A

US428585A - Blackboard-eraser

Info

Publication number: US428585A
Authority: US
Publication date: 1890-05-20
Anticipated expiration: 1907-05-20

Description

(No Model.)

P. PANNING.

BLAGKBOARD ERASBR.

No. 428,585. Patented May 20, 1890.

.9 @en orv @JM Wyk/a (23 @mff/A UNITED STATES PATENT OFFICE.

FRANK FANNING, OF NEVTON, MASSACHUSETTS, ASSIGNOR TO HIMSELF, AND ANSON B.. GUILFORD, OF JERSEY CITY, NEW JERSEY.

BLACKBOARD-ERASER.

SPECIFICATION forming part of Letters Patent No. 428,585, dated May 20, 1890.

Application tiled November 2, 1889. Serial No. 329,094. (No model.)

To all whom t may concern.-

Be it known that I, FRANK FANNING, of the city of Newton, in the county of Middlesex and State of Massachusetts, have invented an Improved Eraser forBlackboards; and I hereby declare the following to be a full and exact description thereof, reference being had to the accompanying drawings,which,together with the letters of reference thereon, make a part of this specification.

Vith reference to the drawings, Figure 1 is a perspective view of the improved eraser. Fig. 2 is a side elevation. Fig. 3 is an edge view of the pad or strip vof erasing material. Fig. 4 is an edge view of the clasp c. Fig. 5 is a plan of the same. Fig. 6 is an end view of the eraser, clasp omitted. Fig. 7 is an elevation of pin e, and Fig. 8 is a similar elevation view at a right angle.

My invention is in the nature of an easily attachable and detachable erasing pad or strip and holding device.

It consists of two blocks of wood or any suitable material, having their ends butted together and hinged to each other at the surface on the face side, (see Fig. 2,) anda strip of lambs skin with wool attached, or of plush, carpeting, 0r other suitable flexible material suitable for erasing chalk and like marks, with means and conveniences for attaching and detaching the latter to and from the former. One of these blocks is marked a, the other b, and the erasing material is marked h. The blocks are hinged together, so that they may be made to assume an angular position relatively, as indicated in Fig. 2 by angular dotted lines. Vhen in this angular relative position, the ends away from the hinge approach each other, as indicated by dotted arcs. In this position itis easy to insert the ends of the erasing material h into the slots j. The pins e are then forced through the erasing material, passing into holes and slot or groove 2, as seen in the figures. Vhen this is done, the blocks a b are brought back from the relative angular position into their normal rectilinear position, as shown, in which movement the hinged blocks act as a toggle to stretch the erasing material to a good working tension. At the same time and by the same movement the clasp c, or spring hook or latch, by either of which names it may appropriately be called, is forced up the incline Z, (shown in Fig l and dotted in in Fig. 2,) and on reaching the socket m the hook part is snapped into it by the recoil of its springshank, and so the blocks a h, with the so-attached erasing material, are held firmly in the flat rectilinear position ready for use.

Whenever it becomes desirable to renew the erasing material 7L or to remove it for cleaning, the reversed process is gone through with, viz: The clasp is lifted out of socket m, the blocks are made to resume the angular relative position, the pins lifted so far as to release the material, and it is so detached. It is then cleaned and replaced, or, what is better, as will usually be done, a new strip or pad of material is substituted, which will be provided in suitable number, accompanying the other part of the device, which may be used indefinitely.

The advantages of this device in cleanliness, in facility of renewal of the erasing-pad, the strength and security of holding device, its simplicity and consequent inexpensiveness, and adaptation to its purpose are so obvious that it is unnecessary to enlarge upon them. The materials other than those already mentioned, and they also, may be of any suitable kinds, plenty of which are well known in the art. The grooves CZ give access to pins c. back or connecting bar.

The groove e' may, if preferred, be made in the face of the block, and the pins c be put in therefrom.

I claiml. The eraser composed of two blocks a Z), the thick ends of which are hinged directly to each other and form sufficient abutting bases for each other to enable them to be held in rectilinear relation to each other by means of a hinge at the face and a hook-latch at their back, and an erasing pad or fabric attached to the outer ends and drawn over their face, substantially as described.

2. The latch c, in combination with the two hinged retaining-blocks a Z9 and an attached erasing-pad, substantially as described.

3. The hook-latch c upon the back, in combination with the broad end base, abutting The grooves i are to receive theirv IOO :md directly hin ged together, blocks a Y), the face hinge, and pad attached to the outer ends of said hinged blocks.

L The grooves (l in blocks a b, in Combina- Jsion with the pins e, substantially as and for the purpose set ti'orlvh.

5. The blocks a I), provided with the slots j, in Combination with the pins e and erasingpad 71,.

G. In :i blaekbomd-ernser, the block n, provided with the incline in combination With the block b and clasp e.

7. The socket m, in combination with the hinged blocks and Clasp-latch C.

S. The combination of the two hinged blocks 15 having' the inortise or socket m and incline the pad h, pins e, and clasp-latch o.

9. The combination of the directly-hingedtogether blocks a Z) end the attached pad and hook-latch upon their back opposite the hinge, zo substantially as described.

FRANK FANNING.

XVituesses:

IIADLEY P. IIANsoN, D. N. B. COFFIN.