US1916019A - Blade sharpener - Google Patents

Description

June 27, 1933. N SCHWARTZ 1,916,019

` BLADE SHARPENER Filed Nov. 17, 1930 NUN WITNESSES therethrough.

Patented June 27, 1933 PATENT oFFIeE NATHAN SCHWARTZ, F NEW YORK, N. Y.

BLADE SHARPENER' vApplication. iiled November 17, 1930. Serial No. 496,291.

This invention relates generally to the class ofsharpening devices for edged tools, and has particular reference to a device which 1s especially designed for the purpose of sharpening flexible double-edged safety razor blades, the same being in the nature o an improvement upon my copending applications, respectively bearing Serial Nos. 478,729 and 487,312. e

The present inventionbroadly aims to provide a device of the indicated character which includes a hollow or concave sharpening surface constructed of a material which oiiers a greater friction than glass without imparting an abrasive action to the cutting edges of the blade. 'x

The invention further aims to provide a sharpening device of this character which includes a plurality of sharpening surfaces of hollow concave configuration, one of which is of glass and one of which is of a material such .as ureal formaldehyde, synthetic resin or an equivalent non-abrasive material which offers a greater friction than glass, to provide together with the glass, sharpening surfaces of diiierent characters for impartingaproper cutting edge.

Other objects of the invention residerin the provisionof a sharpening device whichI is simple and-compact in its construction, inexpensive/to manufacture and which is highly eiiicient in its purpose.

With" the above recited and other objects in view, reference is had to the following description and accompanying drawing, in which Ythere is exhibited one example or embodiment of the invention, while the claims define the actual scope of the same.

in the drawing:

Figure 1 is a perspective view illustrating the device in use.

Figure 2' is a transverse sectional view Figure 3 is a longitudinal sectional View thereof.

Referring to the drawing by characters of reference, 5 designates a casing of hard rubber, metal or any other suitable material, having a top wall 6 and side walls 7 and having a slight yieldability. The inner faces of the side walls 7 are provided with longitudinally extending substantially T-sha-ped A grooves 8 for snugly receiving the T-shaped sides 9 of an arcuate sharpening element l0 which is thus suspended between said side walls. The sharpening element 1() is preferably constructed of glass and presents an inner or upper generally concave or hollow sharpening face 1,1. The face 11 is further provided with contiguous longitudinally ex- 69 tending convex areas 12, over which the opposite cutting edges A of a flexible double-edged razor blade B are adapted to be moved frictional contact, to impart a sharpening action thereto, in the manner'illustrated in 55 Figures 1 and 2 of the drawing. One end of each groove 8 extends through the front face of the casing 5,V while the opposite end 14 ci each groove terminates within the rear face of the casing to prevent displacement 70 of the element through the rear end of the casing. The upper wall 6 ofthe casing is provided with a medially depressed or downwardly bowed arcuate portion 15, within which is irictionally held an arcuate sharpening element l16 having a hollow or concave upper sharpening surface 17. The element 16 1s made of a material suchas urea formaldehyde, synthetic resin or equivalents thereof,

which offers a greater friction or higher coeiiicient of friction than glass without imparting an abrasive action to the cutting edges of a blade, and is designed to initially receive thereon the blade B for either lateral or longitudinal reciprocations, to impart an initial sharpening action to 1 the blade edges for generating heat for static electricity while leveling or correcting distortion of the blade edges which causesdullness, after which a finished sharpening action is obtained on the 9 surface 12\ of the sharpening element 10,

where the contiguous convexities of said surface 11 set up a hammering action as the blade is moved laterallyy thereover, to create a further and final correction of the distor- 9 tion after the blade has been initially prepared by heating and charging the same with static electricity on the irst mentioned surface 17. In practice, the upper wall 6 may bf?, provided .with inwardly directed longitudinally extending ianges 18 with which the opposite side edges of the element 16 abut, While a flange` 19 may be provided Hush with the rear face of the casing to abut with the rear end of the element 16. While there has been illustrated and described a single and preferred embodiment of the invention, it is to be clearly understood that no limitation is necessarily made to the precise structural details, but that modifications and variations thereof which properly fall Within the scope of the claims may be resorted to when found expedient.

What is claimed is:

1. A sharpening element for flexible double-edged razor blades, including a casing, a concave sharpening body, and longitudinally-extending grooves provided in the opposite faces of said casing, said sharpening body having its upper ends appropriately shaped to interlit in the said grooves in the casing for holding the said sharpening body in position in the casing.

Q. A sharpening element for flexible double-edged razor blades including a casing having a top Wall and depending side Walls at opposite side edges of the top Wall, a concave sharpening body carried by the top Wall and a second concave sharpening body suspended by the side Walls, having detachable connection therewith and serving to connect and brace the side Walls.

NATHAN SCHWARTZ.

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