No part
zoom_out loupe Click on this icon or hold down the shift key to magnify while moving over the patent image. zoom_in
home Home help_outline Help
 
 
   
parts

Stropping Device

Patent US860831

Invention Razor-Stropping Device

Filed Saturday, 7th July 1906

Published Tuesday, 23rd July 1907

Inventor William Sharples

Language English

CPC Classification:   
B24D15/08
  • B24D15/08
    Hand tools or other devices for non-rotary grinding, polishing, or stropping specially designed for sharpening cutting edges of knives; of razors
  • B
    Performing Operations; Transporting
  • B24
    Grinding; Polishing
  • B24D
    Tools For Grinding, Buffing, Or Sharpening
  • B24D15/00
    Hand tools or other devices for non-rotary grinding, polishing, or stropping
  • B24D15/06
    Hand tools or other devices for non-rotary grinding, polishing, or stropping specially designed for sharpening cutting edges

For a full resolution version of the images click here

A PDF version of the original patent can be found here.

United States Patent Office.

William Sharples, of Syracuse, New York. Razor-Stropping Device.
No. 860,831. Specification of Letters Patent. Patented July 23, 1907.
Application filed July 7, 1906. Serial No. 325,136

To all whom it may concern:

Be it known that I, William Sharples, of Syracuse, in the county of Onondaga, in the State of New York, have invented new and useful Improvements in Razor-Stropping Devices, of which the following, taken in connection with the accompanying drawings, is a full, clear, and exact description.

This invention relates to improvements in razor-stropping devices in which a flexible razor-strop is operated by hand over suitable rollers to transmit oscillatory motion to a razor holder to move the blade alternately against opposite sides of the strop as it is drawn back and forth over the rollers.

My object is to increase the working efficiency of this class of devices by increasing and maintaining a uniform lap of the razor-strop upon the roller which actuates the razor holder so that any variation in the position of the hands while drawing the razor-strop over the roller does not affect the angle of the portions of the strop between which the razor-holder oscillates.

Another object is to locate the razor holder so as to support the razor with the edge of the blade uppermost thereby utilizing the weight of the razor to aid in its retention in the holder, and reducing the liability of accidental displacement, or disengagement of the blade with the clamp as the strop is drawn against the blade towards its edge.

A further object is to reduce the number of parts and cost of the frame by making it in one piece and interlocking the ends to prevent spreading of the sides and to enable the rollers to be quickly and easily inserted and removed to and from their operative positions.

A still further object is to connect the razor holder with its actuating roller by sliding interlocking connections, thereby avoiding the use of toothed gears and consequent “back-lash” or lost motion, which invariably causes more or less mutilation of the strop by the razor blade.

In the drawings—Figures 1 and 2 are respectively an end view and side elevation of my improved razor-stropping device. Figs. 3 and 4 are sectional views taken respectively on lines 3—3, Fig. 2, and 4—4, Fig. 1. Fig. 5 is an inverted plan view of the device seen in Figs. 1 and 2.

The main supporting frame is made of a single piece of sheet metal, bent in a rectangular form, as best seen in Fig. 2, forming a flat top —1—; flat ends —2— and —3— and a flat bottom —4—, which latter is formed by the ends of the sheet metal strip meeting at substantially the longitudinal center of the bottom of the frame and having their extremities interlocked with each other by a dove-tail tongue —5— interfitting with a dove-tail groove —6—. This tongue and groove hold the sides of the frame against spreading or compression strains, the meeting ends being further secured together by bolts —7— to prevent accidental displacement of the interfitting tongue and groove.

One of the sides or ends of the frame, as —3—, is provided with an opening —8— to permit the insertion and removal of the razor-blades, as —9—, into its oscillatory holder, as —10—. This holder —10— preferably consists of a single piece of sheet metal having its intermediate portion bent around and secured to a rock-shaft —11— centrally journaled in the frame below the opening —8— and having its longitudinal edges extended upwardly above the rock-shaft and lower edge of the opening —8— forming opposite spring jaws between which the back of the razor is adapted to be inserted, as best seen in Fig. 3. The distance between the sides —2— and —3— of the main supporting frame is slightly greater than the length of the razor-blade so as to allow ample clearance for said blade while being oscillated between said ends. The blade-holder —10— is substantially co-extensive with the length or distance between the sides —2— and —8—, in which the rock-shaft —11— is journaled so that the gripping jaws of said holder engage the back of the blade throughout the greater portion of its length, thereby holding the entire blade in the same radial plane. One end of the rock-shaft —11— protrudes a sufficient distance through and beyond the side —3— of the supporting frame to receive a crank-arm —12— which is secured to the rock-shaft —11— and is provided with an eccentric pin or stud —13— having sliding interlocking connection with a crank-arm —14— on the adjacent end of a similar rock-shaft —15—. This latter rock-shaft —15— is journaled in the sides 2— and —3— of the supporting frame directly below the rock-shaft —11—, and upon its intermediate portion is secured a friction roller —16— which is engaged by the razor-strop, as —17—.

The crank-arm 14— on the rock-shaft 15— is provided with a radially elongated slot —18— at one side of its center of oscillation and in which the pin or stud —13— rides. In other words the crank-arms 12— and 14— have sliding interlocking connection with each other between their axes of oscillation, the shaft 15— constituting the driving element to transmit oscillatory motion through the medium of the crank-arms 14— and 12— to the rock-shaft —11— and its razor holder —10—, motion being imparted to the rock-shaft 15— by moving the razor-strop —17— endwise across the face of the roller 16—, in a manner presently described. The rock-shafts —11— and 15— are journaled in the sides —2— and —3— of the supporting frame in the same vertical plane substantially midway between the edges of said frame and near the bottom, which is somewhat narrower than the top to afford free action or clearance for the depending ends of the razor-strop, as best seen in Figs. 1 and 3. Additional rollers —20— are journaled in the sides or ends —2— and —3— near the top and equidistant from and at opposite sides of the vertical plane of the axes of the rock-shafts —11— and 15— so that the axes of the rollers 15— and —20— are disposed in the points of an isosceles triangle having its apex at the bottom or coincident with the axis of the roller 15— and its base at the top and parallel with the upper side —1— of the supporting frame. These rollers 15— and —20— are parallel and the razor-strop —17— has intermediate portion looped around the lower face of the roller 15— and its opposite ends extended upwardly over the inner sides and top of the rollers —20— and extended downwardly at the outer sides of said rollers a sufficient distance to be engaged by the hand of the operator and drawn endwise around the rollers back and forth.

The angle formed by the portions of the strop between the rollers 15— and —20— and against which the razor is impressed is such as to cause the blade of the razor to lie nearly flatwise against the razor-strop when moving in the direction indicated by arrows —X—. By passing the central portion of the strop in the manner described around the rollers 15— and —20— the angle of the portions of the belt engaged by the razor blade is constant. By drawing back and forth upon the ends of the razor strop the portions between the rollers 15— and —20— are kept reasonably tight and rocking motion is imparted to the roller 15—, which in turn, imparts similar motion, but in the opposite direction to the razor holder —10—, thereby throwing the edge of the razor against the upwardly moving sides of the portion of the strop between the rollers 15— and —20—. This back and forth movement of the strop is repeated until the razor blade has acquired the desired edge.

What I claim:

1. In a razor stropping machine, of the class described, a supporting frame consisting of a single piece of sheet metal bent into rectangular form and having its ends interlocked with each other to prevent spreading of the sides, an oscillatory razor holder journaled in the frame, a roller also journaled in the frame, sliding interlocking connections between the roller and holder and a razor-strop engaging the roller and adapted to be drawn back and forth for imparting rotary motion to said roller.

2. In a razor-stropping device, a one-piece frame of sheet metal bent into a rectangular form and having its ends interlocked with each other, a roller centrally journaled in the frame near the bottom, additional rollers journaled in the frame near the top at opposite sides of the vertical plane of the first named roller, a razor-strop passing around said rollers, a razor holder above the first named roller and between the portions of the strop connecting said roller, and means actuated by the first named roller for imparting oscillatory movement to the razor holder.

3. In a razor stropping device, a supporting frame consisting of a single piece of sheet metal bent into rectangular form and having its ends meeting at the bottom substantially midway between the sides, the ends of said piece having interlocking members to prevent spreading of the sides, means to hold said ends in the same plane, a roller journaled in the opposite sides of the frame near the bottom, additional rollers journaled in the frame near the top, the rock-shaft also journaled in the sides of the frame between the lower roller and upper rollers, a strop passed under the lower roller and over the upper rollers, and having its ends hanging down from the outer sides of the upper rollers, a razor holder secured to the rock-shaft and provided with spring jaws opening at the top for receiving and retaining the razor, and means for transmitting motion from the lower roller to the rock-shaft to oscillate the latter as the strop is moved longitudinally.

In witness whereof I have hereunto set my hand this 3rd day of July, 1906.

Wm. Sharples.

Witnesses:

Howard P. Denison,

Mildred M. Nott.