Year: 1886

page_text: therewith.
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co, Patent Agents,
Southampton Buildings, in the County of Middlesex do hereby declare the nature
of this invention and in what manner the same is to be performed, to be par-
ticularly described and ascertained in and by the following statement :-
This invention relates to the class of machines known as lead presses, that is to .
say machines which are adapted for forming pipes or tubes of lead or like metal, or
for covering an insulated conductor with lead. The principle of construction and
operation of the invention is illustrated by a machine designed for the latter
purpose; though it will be understood that by the use of another form of die and
with unimportant changes the same machine may be utilized for making lead pipe.
In these machines, as, generally made, the object is to apply to an insulated
conductor, an even and homogeneous coating of lead. They have for this purpose
a lead chamber provided with a suitable die or nozzle, and a piston or plunger
which acts with a steady pressure upon the lead, tending to force it out through
the die. An insulated conductor is introduced into the lead chamber and is carried
out through the die, the diameter of the conductor being somewhat less than that
of the orifice in the die. Pressure being now applied to the lead in the chamber,
it is forced out through the die forming a coating around the conductor which is
at the same time drawn or forced through the die and wound upon a suitable
reel.
The character of the dies, the construction of the lead chamber and pressure
devices vary very greatly; but the general principle of operation is substantially
similar to that described. In some cases the lead is maintained in a fluid state or
very close to it, while the construction of other machines permits much cooler lead
to be employed. The latter is by far the most desirable in-as-much-as the use of
bot lead is very apt to injure the insulating covering of the wires.

page_text: In all these machines it has been rendered necessary by the principle of con-
struction to periodically insert a fresh supply of lead to the chamber, and in order
to do this it has been necessary to stop the pressure while the fresh material is
placed under the plunger. It is readily seen that this not only interrupts the
continuity of the process, but in cases when the temperature is high it is apt, if
not certain, to destroy the insulation of the conductor which is exposed to the hot
lead while the fresh supply of lead is being introduced. Whether the lead be in
a fluid or semifluid state, or in other words hot or comparatively cool, and whether
the machine is designed to make lead tubing or to cover conductors, it is extremely
desirable that the process should be a continuous one and that some means should
be employed by which the supply of fresh lead may be kept up without sensibly
affecting the pressure or permitting the egress of lead through the die to cease.
To accomplish this is the object of this invention, and the means devised for
doing this are as follows; A lead chamber is used of any ordinary kind but of
great strength, and is provided with a suitable die and, in this case, with a nozzle
of tube extending nearly through the lead chamber in line with the die, for
permitting the wire to enter the chamber and pass through the die.
To the lead chamber is connected a strong tube having a much smaller internal
diameter than the chamber. These parts are secured to a stout frame in any proper
way, and directly in line with the bore of the tube is a plunger, so limited in its
movement that it passes down into the tube for a short distance and is then with-
drawn a certain distance above it. A guide is secured around the end of the tube,
and through or into the guide is passed a strip of cold lead over the opening of the
tube and at right angles thereto.
In using the apparatus the end of the wire which it is desired to cover with lead
is passed through the tube in the lead chamber and the die and the chamber then
filled with lead, which may be simply poured in through the tube above described.
A flame is then applied to the lead chamber that will keep the lead therein
during the further operation of the machine at a temperature of about 300 to
400 degrees Fahrenheit.
When this has been done a continuous lead strip forced along over the bore of
the tube in the above described guide and the plunger reciprocated. Each down-
ward movement of the plunger carries with it into the tube a portion of the lead
strip, whereby the pressure throughout the tube and lead chamber becomes so
great that the lead in the latter is forced out through the die carrying with it the
conductor around which it forms a smooth and even coat.
The lead in the tube above the lead chamber is cold, and requires a very great
pressure to force it down into the lead chamber. This property makes it possible
to utilize the lead as a seal or valve, so that while the plunger is moving upward
and the pressure for a time upon the lead column in the tube relieved, the pressure
within the lead chamber is not sensibly reduced nor is the cold lead in the tube
forced out. The cold lead therefore acts as a valve which permits new lead to be
forced into the tube and thence into the lead chamber, but which prevents any
egress of lead except through the die.
This invention may be embodied in many forms of apparatus and may be carried
out in many different ways. There may be several leading feeding plungers for
each lead chamber, and various devices may be used for moving the cold lead strips
under the plungers.
In the accompanying drawing a simple and efficient form of machine is shown
which will illustrate the principles of the construction and mode of operation of
the invention.
The said drawing is a central vertical cross section of a machine or apparatus
embodying my invention.
The character and plan of construction of the frame, and of all portions of the
device not herein distinctly specified as composing the invention may be varied in
a great many ways.

page_text: A is a strong iron table, B a stout frame bolted thereto and carrying a shaft C
operating by an eccentric or crank, an extensible connecting rod D and cross-
head E working in suitable vertical guides. F is a strong iron or steel box or
chamber joined to the table by a steel cylinder G having a bore of any shape, but
of a section much smaller than that of the chamber F. The tube or cylinder G
passes through the bed plate of the table to which it is screwed or otherwise firmly
secured, and its bore is directly in line with a steel plunger H carried by the
cross-head E.
The plunger H is of such size and shape that it fits smoothly in the bore of the
cylinder and its movement is such that it enters the bore a short distance on each
downward stroke. A guide K consisting of a metal block with a narrow cut-
away portion is fixed over the tube G, so that a lead strip L when inserted in the
cut-away portion will be brought over the orifice or bore of the cylinder. If the
plunger be set in motion it will carry that portion of the lead strip down into
the tube G which lay over the orifice in the tube, so that if the strip be continually
pushed up when the plunger leaves the tube, the latter in a short time will be
filled with lead. The connecting rod D is made extensible in some convenient
way in order that the play or movement of the plunger with reference to the tube
may be adjusted. Any ordinary double screw threaded extension coupling M is
shown as the means for varying the range of movement of the plunger.
The lead chamber F is provided with a common form of die O which may be
a steel block with a small opening through the inner face gradually expanding
towards the outside. A steel tube P of generally tapering form is screwed into
the side of the chamber opposite the die and it extends up to or for a short
distance within the orifice of the die, leaving an annular space through which the
lead is forced.
R is the wire or conductor to be coated. It is passed through the tube P and the
die O and when the pressure is sufficient within the chamber the lead forced out
through the die forms a compact and even sheathing around the conductor. The
wire is then unwound from a reel S and on issuing from the die with its lead
coating it is wound on a reel S¹. Guides T are used to direct and sustain the
wire, wherever it is necessary.
V is the burner or source of heat for warming the lead in the chamber.
In lieu of one plunger two or more may be used and in the same manner the
dies may be increased in number. The plungers, in case more than one is used
may be worked by one shaft and pulley wheel W or by different ones.
Further modifications of the construction of this device it is not important to
describe in detail. It will be readily understood that with the apparatus as shown
or by such changes as are well known in the art it may be used for making tubing
of lead or of any other metal or alloy having like properties. .
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed as communicated to
me by my foreign Correspondent I declare that what
claim is ;-
First. In a wire covering or lead pipe machine, the combination with the lead
chamber provided with a die or orifice, of a reciprocating plunger adapted to
enter an opening or passage communicating with the interior of the chamber,
substantially as set forth.
Second. In a wire covering or lead pipe machine, the combination with a lead
chamber provided with a die or orifice, a reciprocating plunger adapted to enter an
opening or passage communicating with the interior of the lead chamber and of
considerably smaller diameter or section than the chamber, as set forth.
Third. The method of feeding or supplying lead to the pressure chamber of a
wire covering or lead pipe machine, which consists in forcing at intervals cold lead
into said chamber through a contracted passage, and maintaining the lead in the
passage or near the orifice through which it is introduced at a low temperature,

page_text: whereby it acts as a seal or valve against the pressure within the chamber as
set forth.
.
Fourth. The combination with a lead chamber, a former or die for the egress of
the lead when under high pressure a tube of smaller diameter than the chamber,
and a reciprocating plunger adapted to work into and out of the tube for forcing
cold lead through the tube into the chamber.
Fifth. The combination with a supporting frame, a lead chamber provided with
a die for forming lead tubes or the like, one or more tubes entering said chamber,
reciprocating plungers working into and out of the tubes, and guides surrounding
the ends or openings of the tubes and adapted to direct lead strips over said
openings, as set forth.
Sixth. The combination with a lead chamber provided with a lead pipe forming
die or its equivalent, one or more tubes entering the chamber and an adjustable
reciprocating plunger for each tube, the said plungers being adapted to enter the
tubes for a certain distance on each downward stroke, as set forth.
HASELTINE, LAKE & Co.,
Agents for the Applicant.