Friday, May 7, 2010

Hand-cranked portable peening machine

Here's an invention that was designed to peen the edge of a scythe blade when the hand crank is turned.  The device can be taken into the field for convenient use.

Patented in the United States by German inventor Michael Humpfner in 1887, the machine "...allows the scythe to be so struck that no warping or notching can occur even though the metal be extremely thin... obliges the clumsiest and laziest workman to hold the scythe in right position... allows only one point to rest, and the guiding-bow, set at the correct angle, renders too great an inclination of the scythe impossible... The apparatus is mounted in oblique position on one end of a board about fifty centimeters long for the purpose of rendering possible work in the open field, which is done by holding the board fixed on the ground by means of the right knee, while the right hand turns the crank and the left hand draws the scythe through. In this manner my apparatus secures safe sharpening even on the loosest sandy soil and on wet meadows."

The above quotes are from the patent document which can be viewed at:

(Source:  United States Patent Office, Patent number 375708, Issue date Dec 27, 1887, Device for Sharpening Scythes by Michael Humpfner of Frankfort-on-the-Main, Germany.  Patent information found using Google patents.)

1 comment:

  1. Neat, a simple hand powered trip hammer. I've had a similar idea but thought of using a bicycle (cammed rim) so I can use both hands to hold the blade.