Improvements in the Manufacture of Phonogram Duplicates.
Year: 1899

page_text: Date of Application, 21st July, 1899-Accepted, 26th Aug., 1899
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Phonogram Duplicates.
I, HENRY GOODRICH WOLCOTT, of Fishkill-on-Hudson, County of Dutchess,
State of New York, United States of America, do hereby declare the nature of this
invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
This invention relates to an improvement in the manufacture of phonogram,
grammophone, or graphophone duplicates, and its objects is to produce from the
negative copy taken from a wax cylinder upon which the record has first been
produced, any number of duplicates capable of withstanding for a lengthy period,
and it consists, mainly, in evenly pressing by means of a liquid or fluid medium,
a cylinder or tubing of plastic material, or of a material capable of being rendered
plastic by the application of a gentle heat, embedded between said negative copy
of the record and a circumferentially recessed metallic cylinder or piston, towards
and against said negative copy, thus taking an exact impression therefrom, so
that all projections on the inner surface of the latter forming the phonogram
properly speaking, will be reproduced on the outer surface of said plastic cylinder
or tubing in reversed order, so as to form correspondingly shaped small impres-
sions which are an exact duplicate of the original record.
In order to carry my invention into effect I put the negative copy which pre-
ferably is an electro taken from the wax cylinder upon which the record had
first been produced, in a housing of cylindrical form, and further I place the
plastic cylinder or tubing into said electro, whereupon the metallic cylinder or
piston circumferentially recessed to an extent corresponding to the surface of the
record to be copied, is introduced into the plastic cylinder. The said piston is
provided with an axial bore and with radial or lateral bores extending therefrom
towards and into the recessed part of the piston. By introducing compressed
air or by pressing a liquid into the recessed part of the piston by way of said
bores, the plastic cylinder is gently and evenly pressed up to and against the
face of the metallic copy or electro so as to take an exact impression therefrom.
In the accompanying drawing,
6 designates the electro or negative copy of the wax cylinder or record first
taken. The outer diameter of said electro exactly corresponds with the inner
diameter of the housing or strong walled cylinder e so that on inserting the
electro into said cylinder the former will smoothly fit or adhere to the latter.
The plastic cylinder or tubing a preferably consisting of vulcanite, celluloid or
the like is then placed in the electro and into the latter the metallic piston e
is introduced, the recessed part of which having previously been furnished with
a kind of a rubber bag d so that the air or liquid which then is to be pressed
through the piston bores f and g, respectively, into the recessed part or chamber h
of the piston, will act upon the plastic cylinder a without finding a way to escape
through from the annular chamber h formed by the recessed part of the piston.
The pressure thus prevailing in said chamber, will evenly and gently act upon the
plastic cylinder, pressing the latter against the face of the electro thereby taking

page_text: an exact impression therefrom so that even the most minute projections of the
latter will afterwards be found on the plastic cylinder in reversed order and
with all their delicate details just as found in the original record.
As the plastic cylinder is to be chosen a little smaller in size than the internal
room of the electro, the former on subsequently reducing the pressure, can be
removed readily from the latter owing to its yielding capacity and to the
diametrical difference existing between them both. In order to attain the result
aimed at by using merely a moderate pressure in the chamber h either the electro
or the plastic cylinder or both of them may be gently heated before they are
placed into working position so that the plastic cylinder and especially its outer
surface will be capable of more readily taking up the impressions from the
electro. It is obvious that without departing from the nature of my invention
I may introduce the plastic tubing into the electro before the latter has been
placed in the housing c.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
1. The method of producing phonagram duplicates of a material capable of
withstanding for a lengthy period, by evenly pressing by the aid of liquid or
fluid under pressure a plastic tubing into intimate contact with a negative electro
of the record first taken.
2. The method of producing phonogram duplicates of a material capable of
withstanding for a lengthy period by evenly pressing a plastic tubing into
intimate contact with a negative electro of the record first taken, heat being
applied to either or both of them before pressure is exerted..
3. The apparatus for producing phonogram duplicates according to the method
claimed consisting of a cylindrical housing e in which the electro b containing
the plastic tubing a is placed, and of a circumferentially recessed piston e pro-
vided with bores f and g leading to the recessed part or annular chamber h of
said piston.
Dated this 21st day of July 1899.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.