U.S. patent application number 14/859588 was filed with the patent office on 2016-01-14 for machine for forming metal bars.
The applicant listed for this patent is IKOI S.R.L.. Invention is credited to Giovanni FAORO.
Application Number | 20160008874 14/859588 |
Document ID | / |
Family ID | 44554024 |
Filed Date | 2016-01-14 |
United States Patent
Application |
20160008874 |
Kind Code |
A1 |
FAORO; Giovanni |
January 14, 2016 |
MACHINE FOR FORMING METAL BARS
Abstract
A machine for forming metal bars, in particular for producing
ingots made of precious metal such as gold, silver, precious
alloys, as well as other pure metals or different alloys, including
a melting station for melting the metal contained in an ingot
mould, wherein the ingot mould contains an accurate amount of
metal, in the form of powder, grits or swarf of various sizes and a
chemical additive, which creates a chemical reaction with the
impurities contained in the metal. The chemical additive may be any
of boric acid, borax, potassium nitrates, ammonium, sodium, lithium
and potassium and sodium chlorides.
Inventors: |
FAORO; Giovanni; (Bassano
Del Grappa (VI), IT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
IKOI S.R.L. |
San Zeno DI Cassola (IV) |
|
IT |
|
|
Family ID: |
44554024 |
Appl. No.: |
14/859588 |
Filed: |
September 21, 2015 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
14007910 |
Oct 17, 2013 |
9168582 |
|
|
PCT/EP2012/001377 |
Mar 29, 2012 |
|
|
|
14859588 |
|
|
|
|
Current U.S.
Class: |
164/259 ;
164/266 |
Current CPC
Class: |
B22D 21/027 20130101;
B22D 9/003 20130101; B22D 21/025 20130101; B22D 27/00 20130101;
B22D 7/068 20130101; B22D 9/00 20130101; B22D 27/003 20130101; B22D
7/00 20130101; B22D 21/022 20130101; B22D 47/00 20130101; B22D 7/06
20130101; B22D 7/064 20130101; B22D 21/04 20130101; B22D 7/005
20130101; B22D 23/06 20130101 |
International
Class: |
B22D 7/00 20060101
B22D007/00; B22D 27/00 20060101 B22D027/00; B22D 7/06 20060101
B22D007/06 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 1, 2011 |
IT |
VI2011A000076 |
Claims
1. A machine for forming metal bars, in particular for producing
ingots made of precious metal such as gold, silver, precious
alloys, as well as other pure metals or different alloys,
comprising a melting station for melting the metal contained in at
least one ingot mould which includes a cover, wherein said at least
one ingot mould comprises an accurate amount of metal, in the form
of powder, grits or swarf of various sizes and a chemical additive,
which creates a chemical reaction with impurities contained in the
metal wherein said chemical additive is selected from the group
consisting of boric acid, borax, potassium nitrates, ammonium,
sodium, lithium and potassium and sodium chlorides, and
combinations thereof.
2. The machine according to claim 1, wherein said melting station
comprises at least one melting furnace in which one or more ingot
moulds containing said metal and said chemical additive are
pushed.
3. The machine according to claim 1, comprising a station of
secondary addition said station of secondary addition adding an
accurate amount of a second chemical additive in each ingot mould,
on the molten metal, said accurate amount of said second chemical
additive creating a chemical reaction with the impurities contained
in said molten metal, said second chemical additive being selected
from the group consisting of boric acid, borax, potassium nitrates,
ammonium, sodium, lithium and potassium and sodium chlorides, and
combinations thereof.
4. The machine according to claim 3, wherein said station of
secondary addition comprises dosing systems that add said second
chemical additive on the still liquid metal contained in each ingot
mold.
5. The machine according to claim 3, wherein said station of
secondary addition comprises grippers that raise the cover of each
ingot mould.
6. The machine according to claim 3, wherein said station of
secondary addition is incorporated in a single station which also
comprises a solidification station.
7. The machine according to claim 3, wherein said station of
secondary addition comprises an inert environment which comprises
inert gas which prevents the oxidation of said ingot moulds and
said covers and protects the metal still in liquid form against
oxygen.
8. The machine according to claim 7, wherein said inert gas is
nitrogen, argon, or nitrogen-hydrogen mixture.
Description
[0001] This is a divisional application of U.S. patent application
Ser. No. 14/007,910, filed Oct. 17, 2013, which in turn is the
National Stage of PCT/EP2012/001377 filed on Mar. 29, 2012, which
claims priority under 35 U.S.C. .sctn.119 of Italian Application
No. VI2011A000076 filed on Apr. 1, 2011. The international
application under PCT article 21(2) was published in English. The
disclosure of the referenced applications are incorporated herein
by reference.
[0002] The present invention regards a machine for forming metal
bars, in particular for producing ingots made of precious metal
such as gold, silver, precious alloys, as well as other pure metals
or different alloys.
[0003] As known, producing ingots, in particular made of gold,
silver, precious alloys, other pure metals and different alloys, is
usually obtained by means of two different methods.
[0004] When producing light ingots, from 5 g up to 50 g, there is
used a cold moulding and coining process, starting from
semi-finished products, such as cylindrical-shaped preformed pads
or billets.
[0005] When producing ingots with weight varying between 50 g and
50 Kg there is instead used the melting method and subsequent
solidification of the metal in the special moulds. In practice, the
metal to be melted is placed within ladles, in form of powders,
granules or loose raw materials of various sizes, wherein it is
brought to melting. Then the molten metal is poured in single ingot
moulds, generally shaped to form a truncated-trapezoid wherein,
solidifying, it takes the form of an ingot.
[0006] Such two operations, the melting one and the subsequent one
for solidifying the material, must be carried out with special
care, given that the obtained end-product must meet strict and
specific standard requirements.
[0007] Actually the ingots available in the market, besides having
an exact purity if made of pure metal, or an exact percentage of
pure metal if made of an alloy (the so-called "count"), must have
extremely precise dimensions and weight, an external configuration
with regular surfaces, without depressions or cracks, a uniform
coloration and, above all, they must have a perfect internal
metal-graphic structure, without blowholes, microporosities and
structural tensions.
[0008] In order to avoid obtaining faulty ingots not capable of
allowing obtaining "punching", which would thus be considered as
waste material, it is necessary that the entire production cycle be
carried out with much care, in particular during the steps of
melting, solidifying and cooling the metal.
[0009] An object of the present invention is to provide a machine
for forming metal bars, in particular for producing ingots, made of
precious and non-precious material and, which does not have the
drawbacks revealed by the plants of the known type.
[0010] The characteristics of the invention will be made more clear
through the description of a possible embodiment thereof, provided
by way of non-limiting example, with reference to the attached
drawings, wherein:
[0011] FIG. 1 represents an elevational view of the machine
according to the invention.
[0012] As observable from the drawing, the machine according to the
invention, generally indicated with reference 100, comprises a
melting station, indicated with reference 102, for melting the
metal contained in the ingot moulds, indicated with reference
1.
[0013] As can be seen in FIG. 1, on a loading surface of the first
operating station 101 there are positioned the empty ingot moulds
1, interposing between an ingot mould and the subsequent one or
between groups of two or more mutually adjacent ingot moulds,
spacers 2, made of graphite or any other refractory material.
Spacers 2 serve the function of maintaining a predefined distance
between the single ingot moulds or between the groups of ingot
moulds, in a manner such that the ingot moulds 1, forming a "train
of ingot moulds" are positioned, during the forward movement,
always correctly within the work area. Furthermore, said operating
surface is also provided with a pushing device 3, driven variously,
such as by a worm screw, a pneumatic means, hydraulic means or any
other means, which provides for pushing, with a predefined "pitch",
the aforementioned train forward, and then returning and thus
freeing space on the aforementioned loading surface, to allow
depositing further empty ingot moulds.
[0014] According to the invention, in each single ingot mould 1
there is poured an exact weight of metal, in form of powder, grits
or swarf of various sizes and there is added a chemical additive,
which creates a chemical reaction with the impurities contained in
the metal and which is made up of boric acid, borax, potassium
nitrates, ammonium, sodium, lithium and potassium and sodium
chlorides, used separately or mixed. Lastly, in said first station
101 there occurs the positioning of the cover 4 for closing the
filled ingot mould.
[0015] Then, the pushing device 3 pushes the "train" from the
station 101 for supplying the ingot moulds to the melting station
102, wherein there may be a heating furnace 5, in which the ingot
moulds and the spacers slide on a refractory surface in absence of
controlled atmosphere, or a tunnel 6, in which the ingot moulds and
the spacers slide on the surface of the tunnel or on guides,
variously heated, through electrical resistors, by electromagnetic
induction, through burners of the gas type or of any other type, up
to the operating temperature. By way of example, regarding the
ingots made of silver (Ag) such temperature is of about
1150.degree. C. While for the ingots made of gold (Au) it is of
about 1250.degree. C. and in the tunnel or in the guides there is
insufflated inert gas, such as nitrogen, nitrogen-hydrogen mixture
with maximum 4.5% of hydrogen (H), to create an "inert"
environment, which prevents the ingot moulds and the covers from
being subjected to oxidation and thus prevents quick wearing and
keeps the molten metal protected from oxygen.
[0016] Furthermore, with the aim of reducing the heat and the
atmosphere of the inert gas, within the tunnel 6 there is provided
for, at the lateral openings for the inlet and outlet of the
"train", the application of mobile partitions 7 obtained, for
example, with the guillotine technique, which create a mobile or
flexible insulating refractory barrier, the movement thereof being
manual or automatic.
[0017] Then, still from an operational point of view, once the
melting time elapses there is activated the pushing device 3, which
provides for moving the "train" forward. The ingot moulds present
on the loading surface are pushed into the furnace/tunnel 5/6 and
the same, in turn, push the ingot moulds present in the
tunnel/furnace 5/6 to exit, with the aim of allowing the latter,
containing the molten metal, then to pass in the station of
"secondary addition" 103 and, subsequently, in the solidification
station 104.
[0018] From an operational point of view, in the station 103 there
occurs the raising of the cover of the ingot mould, by means of
grippers of the mechanical type, pneumatic type or any other type,
while dosing systems of the mechanical type, pneumatic type or any
other type, add in each single ingot mould 1, on the molten metal,
an accurate amount of chemical additive (dosing element "C"), which
creates a chemical reaction with the impurities contained in the
molten metal. The additive being made up of boric acid, borax,
potassium nitrates, ammonium, sodium, lithium and potassium and
sodium chlorides, used separately or mixed. Subsequently, the cover
is repositioned on the ingot mould.
[0019] Also in the process of "secondary addition" there should be
created an "inert" environment, regarding which there is introduced
a flow of inert gas such as nitrogen, argon or nitrogen-hydrogen
mixture, which prevents oxidation of the ingot moulds and the
covers and protects the metal still in liquid form against
oxygen.
[0020] Due to construction reasons, in some cases the "secondary
addition" station 103 and the solidification station 104 may be
incorporated in a single station 103/104, where the addition and
solidification steps are performed sequentially.
[0021] The invention thus conceived can be subjected to numerous
variants and modifications and the construction details thereof can
be replaced by technically equivalent elements, all falling within
the inventive concept defined by the following claims.
* * * * *