US49764A

US49764A - Scissors-sharpener

Info

Publication number: US49764A
Authority: US
Publication date: 1865-09-05
Anticipated expiration: 1882-09-05

Description

UNITED STATES PATENT OFFICE.-

THOMAS K. KNAPP, OF WORCESTER, MASSACHUSETTS.

SCISSORS-SHARPENER.

Specification forming part of Letters Patent No. 49,764, dated September 5, 1865.

To all whom it 'may concern.-

Beit known that I, T. K. KNAPP, of the city and county of Worcester, and State of Massachusetts, have invented certain new and useful Improvements in Scissors-Sharpeners; and I do hereby declare that the following is a full, clear, and exact description ofthe same, reference being had to the accompanying drawings, forming a part of this specification, in which- Figure 14 represents a perspective view of my said improvements, and Fig. 2 represents a longitudinal section.

In the drawings, A represents the frame of the Sharpener, which is supported in this instance by legs a a. The top of frame A has a slit or opening, b, the left-hand lip, B, rising somewhat higher than the other, as fully shown in the drawings. A metal plate, E, is secured to the front end of frame A, and a circular steel knife, C, is fastened to the side` of said plate by a screw, D, as fully indicated in the drawings. There are two guide-pins, c c, upon the outside oi' plate E, by which the height of knife O is regulated.

The operation is as follows: The Sharpener being arranged for use as shown in Fig. l, the operator takes a pair of scissors, opens the same, and, placing the blade in the slit b, with the inside toward lip B and the edge resting upon the top of the cutter C and bottom g ot' the slit b, draws the blade to be sharpened from heel to point over the top edge of the cutter O.

By the above operation the edge of the blade is rendered sharp, the bevel being uniform and smooth, with a slight curve from the cuttingedge to the back, which is the best form to render the action of t-he edge most ecective. The particles of steel removed from the blade by the -cutter C fall into the opening e and thence pass down and out atf. The opening in cutter O for the screw D is made larger than the screw, as seen at d, so that as the cutter wears or is turned off it can be moved up to its proper position. After one point in the cutter is worn so as to become dull it can be turned a little, when a new cutting-edge will be presented for use. After the entire surface has become dull the cutter can be removed and its periphery turned oft or ground. when it can be used as before.

This device with careful usage will la-st a hundred years. W'hen the scissor-blades have been sharpened a smooth cutting-edge is produced in all cases, thus avoiding the wire-edge frequently found after scissors have been sharpened in the ordinary manner.

The body A may be made of metal and cast hollow,in which case plate E may be dispensed with. Instead ot' pins c o a groove might be turned in the end of frame A to receive the cutter, the upper edge of the groove being the right distance for the edge of the cutter.

I do not wish to be understood as claiming anything shown or described in the patent granted to George Hinmnn, February 23, 1858, or in the patentgranted to John O. Loveland, March 30, 1858.

Having described my improved scissorssharpener, what I claim as of my invention, and desire to secure by Letters Patent, is-

The combination, with the frame A, of the discharge-opening e j' and circular cutter O, having an enlarged hole, d, through its center. whereby all clogging ofthe instrument is pre'- veuted, while the periphery ot' the cutter O can be ground or turned ott without impairing its operation, all as set forth.

THOS. K. KNAPP.

Witnesses:

H. L. FULLER, Trios. H. DODGE.