Improvements in Electric Welding Apparatus.
Year: 1891

page_text: COMPLETE SPECIFICATION.
Improvements in Electric Welding Apparatus.
I, MARK WESLEY DEWEY, of the City of Syracuse, in the State of New
York, United States of America, Electrician, do hereby declare the nature of my
nvention for IMPROVEMENTS IN ELECTRIC WELDING APPARATUS," and in
what manner the same is to be performed, to be particularly described and
scertained in and by the following statement:-
My invention relates to certain improvements in apparatus for electric welding,
nd is especially applicable to the heating of curved forms, such as rings, hoops,
ires etc
The object of my invention is to provide simple and efficient means for rapidly
velding the ends of pieces or a ring together all as hereinafter described and
The object of my invention is to provide simple and efficient means for rapidly
velding the ends of pieces or a ring together all as hereinafter described and
In the accompanying drawings forming a part of this Specification,
Figure 1 is a side elevation of an apparatus embodying my invention,
Figure 2 is a front elevation of the same,
Figure 3 is a top view,
Figures 4 and 5 are side elevations of a part of modified forms of apparatus, and
Figures 6 to 10 show rings or hoops with different kinds of lap-joints before and
after a union is effected.
Referring specifically to Figures 1, 2 and 3, A. represents a frame or pedestal
supporting a single clamp and an insulated table between but below the jaws
thereof. B is a stationary jaw of the clamp and B' is a movable jaw preferably
pivoted to the frame A and movable toward and from the stationary jaw. These
jaws are each connected to a terminal of a circuit carrying an electric heating
current. The terminal C is connected with B and the terminal C' with B¹.
a indicates insulation to insulate one jaw from the other. The table or hoop
support A is preferably made of slate or fire-brick or other non-conducting-
heating-resisting substance and is more or less curved to permit the part of the
hoop D where the joint is made, to rest upon it between the jaws of the clamp.
The jaws are adapted to compress the work laterally to form lap-joints. The
faces of the jaws which are brought in contact with the work may be plain or
grooved to fit more or less the shape of the work and to make good electrical
contact therewith. Extending through the movable jaw and in a direction toward
the base of the stationary jaw is a large screw 6 forming an adjustable stop and
short circuiting device. The said screw is adapted to approach or recede from the
base of the stationary jaw B and is set or adjusted according to the size or cross-
section of the joint. The movable jaw is preferably normally separated from the
other jaw by its weight or an auxiliary weight or a spring to admit the joint to be
welded between the jaws easily and freely. When the movable jaw is moved
toward the joint and the opposite jaw, to effect a welding operation, it first comes
in contact with the work to close the circuit therethrough to heat and soften the
work which is performed quickly, then as the pressure with the clamp is continued
the pieces or the ends of a piece are forced together to complete the union of the
parts. When the joint has been compressed to the desired extent, the enlarged
end of the stop-screw b comes in contact with the base of the stationary jaw so that
further pressure cannot be applied, and, so that the current will be short circuited
through the stop b and base of stationary jaw B to prevent too much pressure, and
the work from being burnt or kept heated too long. As soon as the jaw Blis
moved as far as the stop will allow, the said jaw is allowed to recede from the joint
and the work is removed.
In welding the joints of hoops or rings rapidly, the hands of the operator are
•

page_text: entirely occupied in handling and holding the work, therefore, in order to operate
the clamp or the movable jaw thereof, I connect a suitable treadle c to be operated
by the foot, by a rod c¹ with an arm projecting from the jaw B'. The treadle c
is preferably so fulcrumed that when it is depressed by the foot the movable jaw
will approach the other.
Figure 3 shows stops d d to limit the length of the lap. These stops may be
strips of insulating material as mica or high resisting material as platinum, sup-
ported by brackets e e secured to the table A' and with their free ends extending
toward each other and toward the centre of the table. The stops may be placed
a greater or less distance apart according to the length of the lap joint to be made.
Fig. 6 shows such a joint after it is completed. When a joint is made after the
ends are tapered as shown in Figure 7, such guides will not be necessary.
Referring again to Figs. 1 and 2, E is a well known counter electro-motive force
device to be employed when the current passed through the joint is of an alter-
nating character, to prevent said current from short circuiting through the con-
tinuous part of the ring or hoop and heating the same.
Said counter electro-motive force device may be of any suitable and well known
form, but is preferably formed of layers of sheet iron separated by insulating
material and is shaped to enclose the work as shown.
The said counter electro-motive force device is adapted to be moved vertically
toward and from the table A' or the pressure devices or clamp. The said device
is provided on each side with guides or bearings g g to work in the frame A so
that it will be held firmly in place in any position. The device. may be raised,
lowered and held by any suitable means, but a screw is preferred, journaled in the
frame A at each end and passing through a lug on said device E. The device E
is in tivo parts as usual. The parts are hinged together so that the device may be
opened and closed conveniently to admit and remove the ring therefrom. In order
that the device E may be normally open and closed when the work is operated
upon, which is essential, a rod i is connected at one end to the upper part of the
device, which is movable toward and from the lower part, and rests or bears with
its other end upon the treadle lever. The end of the said rod resting, upon the
treadle lever is bifurcated, and arranged so that it will be held in place on said
lever and permit the treadle to be depressed more or less after the device E is
entirely closed.
It will be apparent that the device E is operated simultaneously with the jaw B',
but the former should be closed completely or to the extent desired as soon as the
jaws make contact with the work.
Fig. 4 represents how motion may be transmitted from the treadle to the pivoted
jaw 13 by means of toggle arms. Said arms are jointed together, and to and
between the jaw B' and a bracket or arm A extending from the back of the
frame A. upward behind the said jaw. The rod e¹ is connected, to the central joint
of the toggle, and is drawn down by the treadle when it is desired to move the
jaw B toward the work. With this device greater and increased pressure may be
applied to the joint.
Fig. 5 shows a clamp arranged for welding band hoops or hoops made of sheet
metal. The joints to be made with this apparatus resemble those shown in
Figures 8 and 9 of the drawings. Fig. 10 indicates the joint shown in Fig. 9 after
it has been united and pressed to a certain extent.
By applying more pressure to the joint when it is heated the cross-section may
be decreased until it is not greater, than other portions of the work.
In Fig. 5 an auxiliary weight F is employed to hold the jaws normally open.
Said weight or weights are mounted upon an arin extending back from the
jaw B¹
It will be obvious that the apparatus described is particularly adapted not only
for welding the joints of band hoops but all kinds of hoops or curved forms especially
those made of round wire.
The ends to be welded together may be united without tapering as has been

page_text: clearly shown, or they may be tapered or beveled before they are united in any
suitable manner and by any suitable and well known means.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, 1 declare that what I
claim is:-
1. In an electric welding apparatus, the combination of a clamp adapted to
compress the work laterally and having one jaw insulated from the other, terminals
of an electric circuit connected to said jaws, grooves in the inner faces of said jaws
transverse to the line of movement of the movable jaw, and suitable means to apply
lateral pressure to the work with said clamp.
2. In an electric welding apparatus, the combination of a clamp adapted to
compress the work laterally and having one jaw insulated from the other, a table
or support for the work between but beneath the jaws, terminals of an electric
circuit connected to said jaws, and suitable means to apply lateral pressure to the
work with said clamp.
3. In an electric welding apparatus, the combination of a clamp adapted to
compress the work laterally and having one jaw insulated from the other, terminals
of an electric circuit connected to said jaws, suitable means to apply lateral
pressure to the work with said clamp, grooves in the inner faces of said jaws
transverse to the line of movement of the movable jaw, and a stop to limit the
movement of one of the jaws.
4. In an electric welding apparatus, the combination of a clamp adapted to
compress the work laterally and having one jaw insulated from the other, terminals
of an electric circuit connected to said jaws, suitable means to apply lateral pressure
to the work with said clamp, and an adjustable stop to limit the movement of one
of the jaws.
5. In an electric welding apparatus, the combination of a clamp adapted to
compress the work laterally and having one jaw insulated from the other, terminals
of an electric circuit connected to said jaws, suitable means to apply lateral pressure
to the work with said clamp, and an automatic adjustable cut-out or short circuiting
device for the purpose described.
6. In combination with an electric lap-joint welding apparatus, of stops for
limiting the length of the lap.
7. In combination with an electric lap-joint welding apparatus, of adjustable
stops for limiting the length of the lap.
8. In a ring or hoop welding apparatus, a counter electro-motive force device
supported on the frame of the welding apparatus, and adapted to be moved toward
and from the pressure devices to accommodate different sizes or diameters
of hoops.
9. In a ring or hoop welding apparatus, a counter electro-motive force device
supported on the frame of the welding apparatus, and means to automatically
operate or open and close said device.
10. In a ring or hoop welding apparatus, a counter electro-motive force device
supported on the frame of the welding apparatus, and means to automatically
operate or open and close said device, simultaneously with the movement of the
pressure devices.
11. In a ring or hoop welding apparatus, a counter electro-motive force device
supported on the frame of the welding apparatus, and a treadle to operate or
open and close said device.
1
1001
MARK WESLEY DEWEY.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicant.