Improvements in Apparatus for Hardening and Tempering by Electricity.
Year: 1888

page_text: Date of Application, 29th Aug. 1888
Specification Accepted, 16th Nov., 1888
Improvements in Apparatus for Hardening and Tempering by
Electricity.
A communication from abroad by PHILIP DIEHL, of Elizabeth, Union County,
New Jersey, United States of America, Electrician.
I WILLIAM PHILLIPS THOMPSON, F.C.S., M.L.M.E., of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Manchester, both
in the County of Lancaster, and 323, High Holborn, in the County of Middlesex, Civil
Engineer, 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 :-
The invention relates especially to the process of hardening and tempering small
metal objects, such for instance as needles.
The invention consists in heating a suitable tube chute or conveyer, through which
the objects to be hardened may pass, to any required temperature by means of electric
currents, and in causing the objects to move through the same while so heated with
any required speed so that they may be heated to the required temperature. As they
are discharged from the tube or chute they may be dropped into a vessel of oil or
other suitable material.
In carrying out the invention it is convenient to employ a dynamo electric generator
or other suitable source of electric currents in connection with an inclined tube, duct,
chute or conveyer, which constitutes a portion of the electric circuit and is therefore
made of electrical conducting material. The current is of such character as to heat
this chute to any required temperature. The points of electrical connection with the
The
chute may be changed, if desired, so as to vary the length which is heated.
strength of current may also be varied as required, thus varying the temperature to
which the chute is raised. The chamber may be inclined from a horizontal position
and suitable means may be provided for turning or vibrating the heating chamber,
so that the objects will readily pass through it. A suitable feeding device delivers
the articles to the heating chamber with such frequency as may be required.
The invention will be more fully described in connection with the accompanying

page_text: drawings, illustrating various forms of devices for carrying it into operation. In these
drawings, Figure 1 is a side elevation and Figure 2 a plan view of a suitable
apparatus. Figures 3 and 4 are respectively a side elevation and a plan of a modified
form. Figure 5 is a detail of a form of feeder which may be employed. Figure 6
is a detail of one of the binding-posts for securing electrical connection. Figures 7
and 8 illustrate modified forms of heating chambers or chutes.
Referring to the figures: A, represents a suitable source of electric currents, and B
a tube or chute which is to be heated to any required temperature by currents from
the source. The source of electric currents may be a generator of any suitable
character, such for instance as a shunt-wound dynamo, and the currents therefrom may
be regulated in any required, well-known manner. One pole of the source of currents
is connected, by a conductor 1, with the metal supporting one end of the conducting
chute B, the other end of this chute is connected, by the conductor 2, with the other
pole of the generator A. The chute B is inclined sufficiently to allow the needles or
other articles to pass readily through it. One end of the chute is here shown as being
supported upon a standard (which carries a wheel E' geared with a wheel E2 upon
the tube. The wheel E' is revolved in any convenient manner, and thus the chute B
is revolved continuously. This causes the articles passing through the chute to pass
down its length and to be constantly brought into contact with different portions of
the heated surface. The lower end of the chute is carried in a collar E³, which in
turn is supported from a pillar (2. The height of this end of the chute may be
regulated by an adjustable collar E supported upon an adjustable screw E' carried by
the pillar C. The collar E may also carry a tube Es which extends into a vessel F
for containing oil or other suitable substance in which the articles are dropped as they
pass from the chute B.
The needles or other articles are fed to the chute B by means of a feeder or
conveyer H of any suitable form; that here shown consists of two threaded rods '
and, which are revolved in opposite directions and which are at such distance
apart as to receive the respective ends of the articles and thus convey them from one
end to the other separately. At the end adjacent to the chute, they are dropped into
a receiving tube K, which delivers them to the chute B. The threaded rods h¹ and '
may be turned in opposite directions by a belt n coupling the wheel E with the belt-
wheel n', which in turn communicates its motion to the gear-wheel n¹ and n³ upon the
respective rods.
For the purpose of modifying the active length of the chute B, or the portion
which is heated, a sliding collar p may be moved along its length by means of a
lever p', which couples the collar in any suitable manner with a support p² connected
with the pillar C and thus in electrical connection therewith. The lever plis pivoted
to the collar and this permits movement of the latter a short distance which is all
that is necessary in practice; but the movement may be varied by changing the
length of the support 22 and the link connecting it with the lever pl. This collar may
be connected by suitable pins p³ and p¹ with the supporting collar E of the corre-
sponding end of the chute B, so that it is prevented from turning.
In Figures 3 and 4 a modification is illustrated, in which the tube B is vibrated,
instead of being revolved. This is accomplished by supporting the upper end of the
chute above a revolving cogged wheel or can R, which is turned at any required
speed in any convenient manner. The end of the tube resting upon this cam is
moved up and down with any required rapidity, thus tending to cause the articles to
move toward the lower end of the chute. In this instance electrical connections are
made directly with collars s³ and s². The former is adjustable along the length of the
chute, and thus the portion of the chute which is in the electric circuit may be
varied.
In case the chute is vibrated either vertically or laterally, instead of being revolved,
it may be of other form than tubular, thus it may be U-shaped, or V-shaped, as
shown in Figure 7 or in the form of a section of the tube, as shown in Figure 8. lt
may be convenient in either of these instances to cover the open surface with trans-
parent material such as mica.

page_text: The operation of the apparatus will be evident without further explanation, and it
is evident that various different forms of apparatus may be employed to carry the
invention into effect.
After the needles or other articles have been passed through the chute and heated
to such temperature as may be required for hardening them, they may be passed
through as many more times as may be required and at such temperatures as may be
necessary for tempering or toning them.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me
by my foreign correspondent, I declare that what I claim is:-
1. An apparatus for hardening or tempering, consisting of the combination of a
chute or conveyer, a feeder delivering the articles to be hardened or tempered thereto,
a source of electric currents having its circuit through the chute or conveyer, whereby
the latter is heated, an agitator or vibrator moving the conveyer and causing the
articles to pass through the same, and a vessel for containing the cooling bath into
which the articles may be delivered from the chute.
2. In an apparatus for hardening or tempering, the combination with a chute or
conveyer through which the articles to be operated upon may be passed, and a source
of electricity having its respective poles connected with different points in the length
of said chute or conveyer.
3. In an apparatus for hardening or tempering needles and similar articles, the
combination of a heating chute or conveyer, a source of electric currents having its
circuit through said conveyer, and a vibrater applied to the chute, substantially as
described.
Dated this 28th day of August 1888.
WM. P. THOMPSON & Co.,
Agents for the Applicant.