An Improved Method of and Device for Manufacturing Seamless Gold-plated Wire.
Year: 1896

page_text: Date of Application, 24th Jan., 1896-Accepted, 29th Feb., 1896
COMPLETE SPECIFICATION.
An Improved Method of and Device for Manufacturing Seamless
Gold-plated Wire.
I, FRIEDERICH KAMMERER of Pforzheim, in the Grand Duchy of Baden,
German Empire, Manufacturer 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:-
Gold-plated wire has already been manufactured by a variety of methods among
which may be mentioned that in which the ground wire (consisting, for instance, of
copper or brass) after being covered with a gold-foil was rotated around its
longitudinal axis, and was simultaneously therewith exposed to a temperature
sufficient to cause the gold to melt, and thus to adhere to said ground wire. This
method although being from a technical as well as from an economical point of view
most probably the best one that existed up to now, possesses nevertheless (if not
practised with care and skill) the serious drawback that the gold easily mixes with
the ground metal, and loses, therefore, a (sometimes great) part of its principal
property, i.e. its color.
My invention relates to means for doing away with the afore mentioned
drawback, and I attain that object in general by welding the gold-foil to the
ground wire by the application of heat and pressure, and in particular by the
employment of a specially constructed matrix and patrix, as fully described
hereinafter.
In carrying my improved method into practice, I first cover the (preferably
quadrangular or square) ground wire with gold-foil by simply wrapping it into
such foil, and I then place the ground wire with its cover into a matrix
consisting of the three parts a¹ a 2 a 3, Fig. 1.
The wire d with its foil is
supported by the low prismatic part a³, and is laterally held by the high, wedge-like
parts a¹ a 2. The latter receive above the wire d the patrix b, and all the parts
mentioned up to this part of my description (a', a 2, a 3, b, d) are then bound
together by means of a wire or wires.
The matrix a' a 2 a 3 is not a matrix proper, but a sort of combined matrix and
patrix, in that it is in a subsequent phase of the process introduced into an auxiliary
matrix c, Fig. 1, and is pressed down into this latter. Said matrix c is, therefore,
not connected with the other parts by the wire or wires afore mentioned.
The parts a' a 2 a 3 b d after being connected as described are introduced into a
furnace, and strongly heated, and said parts are then in their heated state placed
into the auxiliary matrix c, and pressed powerfully down into the latter by any
suitable means. Owing to the strong heat and the strong pressure there occurs a sort
of welding between the gold-foil and the ground metal, and the former adheres very
firmly to the latter at all sides thereof. There is no seam to be perceived, the
color of the gold is not in the least injured, and the whole piece of wire
seems to consist of solid gold.
The intermediate matrix (a' a 2 a 3), or patrix respectively, need not indispensably
consist of three parts. In the modified form of construction shown in Fig. 3 the
middle part a 3 (Fig. 1) is divided into two parts that are combined one with the
side-portion a 4, the other with the side portion a 5. In another form of construction
(Fig. 4) I combine the middle portion a3 (Fig. 1) as a whole with the side-portion a 6,
and, if desired, I may combine with the other side-portion (a 7) the working portion
proper of the patrix 6 (Fig. 1) as also represented in Fig. 4. If the wire to be

page_text: plated with gold after my improved method possesses an octagonal section, I prefer
to employ the construction shown in Fig. 5, in which the size of the middle portion a 8
exceeds considerably that of the side portions a 9 a 10;; the middle portion is formed
into a sort of swage, as is also the top-portion & that replaces the matrix.
Having now particularly described and ascertained. the nature of my said inven-
tion, and in what manner the same is to be described, I declare that what I
claim is :-
1. The method of manufacturing gold-plated wire, consisting in covering, the
ground-wire or ground metal with gold-foil, strongly heating said parts, and
subjecting them at all sides to a strong pressure, substantially as described.
2. The method of manufacturing gold-plated wire, consisting in, wrapping the
ground wire or ground metal with gold-foil, strongly heating said parts within a
furnace and subjecting them in hot state simultaneously at all sides to a strong
pressure by means of a matrix and patrix, substantially as described.
3. As a means for manufacturing gold-plated wire, the combination with a matrix.
having its cavity reduced towards its lower end, of a divided combined matrix and
patrix, the side parts of which are caused to approach each other on being pressed
down into said former matrix, substantially, as shown and described.
Dated this 22nd day of January 1896.
FRIEDERICH KAMMERER,
By Cassell & Co.,
22 Glasshouse Street, Regent Street, London,
Agents for the Applicant.