US475753A

US475753A - Blackboard-eraser

Info

Publication number: US475753A
Authority: US
Publication date: 1892-05-31
Anticipated expiration: 1909-05-31

Description

(No Model.)

L. W. CHASE. BLAGKBOARD ERASER.

No. 475,753. Patented May 31, 1892.

lie was W'kas e f 1 a mi m mm m. h

UNITED STATES PATENT OFFICE.

LEWIS WV. CHASE, OF KIRKSVILLE, MISSOURI.

BLACKBOARD-ERASER.

SPECIFICATION forming part of Letters Patent No. 475,? 53, dated May 31, 1892.

Application filed January 5, 1392. $erial No. 417,129. (No model.)

To all whom it may concern.-

Be it known that I, LEWIS W. CHASE, residing at Kirksville, in the county of Adair and State of Missouri, have invented a new and useful Blackboard-Eraser, of which the following is a specification.

My invention relates to an eraser designed for use on blackboards where chalk, crayon, or other similar material is used for marking.

The object of my invention is to erase and receive and retain within the eraser the dust from the board,which, as is generally known, is very injurious to the eyes, throat, and lungs. I accomplish these objects by the novel construction and arrangement of the various parts of the eraser, as set forth and illustrated by the accompanying drawings.

Figure 1 is aperspective of the entire eraser constructed according to my invention. Fig. 2 is a transverse section of the same, showing a part removed and in elevation. Fig. 3 is a longitudinal section of the eraser.

Like characters indicate like parts in all the figures of the drawings.

The outer box or receptacle may be made of wood and the internal construction preferably of sheet metal, or the entire eraser, except the rubbing device, may be constructed of metal. The external part or box of the eraser A is constructed in a suitable form to be taken with one hand and used. The inverted-V-shaped piece of thin metal B, provided with flanges C O, which serves as a valve, extends the entire length of the inside of the eraser and is made sufficiently flexible by a spring or preferably two springs D D to yield under the usual pressure when in use and force the air out of the box A through the vent E, thereby drawing the dust from the board into the receptacle or box A. The erasing part of the device F may be made of any suitable material, preferably felt, and perforated or constructed in strips, leaving sufficient space between them for the dust to be drawn through into the box A by the suc' tion caused by the yielding of the valve B under the usual pressure. The opening G is for the purpose of removing the dust whenever desired, and is kept closed by asuitable stopper when the eraser is in use.

What I claim as my invention, and desire to secure by Letters Patent, is-

1. A blackboard-eraser having a suctionvalve located therein and extending throughout the length thereof, substantially as described.

2. A blackboard-eraser having a dust-suction valve located therein and a perforated erasing-covering thereover, substantially as described.

3. Ablackboard-eraser consisting of a body having an air-vent and an elongated springactuated valve mounted in said body, substantially as described.

4.. In a blackboard-eraser, the combination of a body having an air-venttherein, a spring actuated V-shaped piece of metal forming a valve, and a perforated erasing-covering, substantially as described.

5. In a blackboard-eraser, the combination of a body having an air-vent, a spring-actuated dust-suction valve mounted in said body having flanges, and a perforated covering for erasing purposes, substantially as described.

' LEWIS W. CHASE.

In presence of- JOHN CAsHEY, H. E. PATTERSON.