An Improved Method of Manufacturing Rods of Parchmentized Fibre.
Year: 1890

page_text: COMPLETE SPECIFICATION.
An Improved Method of Manufacturing Rods of
Parchmentized
Fibre.
1, ROBERT PORTER FRIST, of 1407, Harrison Street, Wilmington, New Castle,
Country, Delaware, one of the United States of America, Mechanical Engineer, do
hereby declare the nature of the said invention and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement:
The object of my invention is to effect the production from parchmentized fibre of
perfectly true and cylindrical rods or bars of any desired diameter or length, and this
object I attain in the manner hereinafter set forth, reference being had to the accom-
panying drawings, in which ;-
'
Fig. 1, is a perspective view of a tool which may be used in carrying out my
invention.
Fig. 2, is a view of a bar illustrating the manner of carrying out my inven-
tion;
and
Figs. 3 and 4, are sectional views showing the action of the tool Fig. 1 upon
the bar.
My invention is intended for making cylindrical bars or rods of that class of
chemically treated fibrous material known in the market under the various names of
Vulcanized Fiber," "Kartavert," "Parchment Paper," "Leatheroid," etc., and
which may be grooped under the general term of "Parchmentized Fiber."
Hitherto much difficulty has been experienced in making perfectly true cylindrical
rods and bars of such material, for the material cannot be turned in a lathe, as it.
will spring under the pressure of the turning tool and thus prevent the production of
a true cylinder.
Attempts have therefore been made to produce the rods by first making a rod or
bar of square, hexagonal, octagonal or other polygonal form, and then subjecting the
same to the action of rollers which reduce it to cylindrical forn, but this method, of
pressing the rods has been found to be ineffective, as the rod is of varying density,
and has a tendency to return to a shape approximating its original polygonal
form.
In carrying out my invention, therefore, I first procure a rod or bar, A, of square
or other polygonal cross section, approximating that of the cross section of the
desired cylindrical rod or bar to be produced, and I then cut off the projecting
corners or angular portions of the bar, by means of cutting blades or tools acting at
points equi-distant from each other around the circumference of the bar, the cutting
operation beginning at one end of the bar and advancing progressively along the
bar from one end to the other.
A tool which may be used in carrying out my invention is that shown in Fig. 1,
said tool consisting of a hollow stem or mandrel, B, reduced at the front end so as
to form four cutting blades, a, located equi-distant from each other around the axis
of the tool, the inuer faces of these blades being concave so that when the tool acts
upon the end of the rod, A, to reduce the same to cylindrical form said cylindrical

page_text: portion will fit snugly to and will be firmly supported at equi-distant points by the
curved inner faces of the cutting bits, a, as shown in Fig. 4, thus preventing any
deflection of the rod or bar which is being acted on and insuring absolute truth of
the cylinder thus produced. A rod or bar of any desired length can be produced the
rod passing completely through the mandrel which has a cylindrical bore extending
from end to end as shown in Fig. 3.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is.
The mode herein described of producing cylindrical rods or bars of parchmentized
fibrous material said mode consisting in first producing a bar of square or other
polygonal form and of a size approximating that of the desired cylindrical rod, and
then removing the projecting corners or angular portions of this bar by means of
cutting tools equi-distantly disposed around the circumference of the cylinder which
is being formed the cutting operation commencing at one end of the bar and con-
tinuing progressively along said bar, substantially as specified.
Dated this 17th day of Anril 1890
DAY, DAVIES & HUNT,
321, High Holborn, London, W.C., Agents for the Applicant.