An Improved Portable Electric Rivetting Machine.
Year: 1899

page_text: Date of Application, 25th Apr.; 1899
Complete Specification Left, 9th Jan., 1900-Accepted, 7th Apr., 1900
PROVISIONAL SPECIFICATION.
An Improved Portable Electric Rivetting Machine.
I, FREDERICK SCHEER DUDGEON, of 30, Great Saint Helens, in the City of London,
Engineer, do hereby declare the nature of this invention, which has been
communicated to me from abroad by Felix von Kodolitsch, of Triest, in the
Empire of Austria, to be as follows:-
This invention consists of a portable rivetting machine in which the rivet is closed
between, and by the operation of, a fixed and a movable jaw, of which the latter is
operated by mechanism driven by electric power whereby a disc is kept constantly
revolving and the rotation of which is transmitted through an electromagnetic
coupling, and the path of the die on the movable jaw is controlled by a parallel link
motion.
According to this invention a disc is kept in rotation by an electric current
immediately adjacent to a second dise to which it may be coupled by electro-magnetic
action and which second disc operates a screw spindle on which is a nut carried by
one end of a lever, and which lever at its other end carries the movable die for making
the rivet heads.
To the top of the screw spindle is attached a star and planet motion which serves
for reversing the motion of the screw spindle in order to return the nut to its first
position preparatory to another stroke.
A dragrod is provided which serves as a guide for the die in order to get the travel
through which the die moves in closing the rivet heads in a straight line.
The machine is intended to be suspended from a crane so that it may be put in to
any position suitable for the work it is required to do.
An Improved Portable Electric Rivetting Machine.
I, FREDERICK SCHEER DUDGEON, of 30, Great Saint Helens, in the City of London,
Engineer, do hereby declare the nature of this invention and in what manner the
same is to be performed, which has been communicated to me from abroad.by
Felix von Kodolitsch, of Triest, in the Empire of Austria, to be particularly described
and ascertained in and by the following statement :―
This invention relates to a portable electric rivetting machine in which the rivets
are closed by the co-operation of a fixed jaw and a movable jaw. The movable jaw is
mounted on a lever actuated by a nut travelling on a rotary screw spindle. The
spindle is driven by an electro-motor by means of an electro-magnetic coupling or

page_text: clutch automatically disconnected when the distance between the two jaws has been
reduced to a certain predetermined minimum. The electro-motor and the coil of the
electro-magnetic clutch connected therewith always rotate in the same direction.
The movable jaw is so attached to the lever actuating it as to be able to swing thereon,
and a guide serves to cause its acting end to travel in a straight line. The apparatus
can be suspended on a crane and used in any position.
One form of such a rivetting machine is shown in the accompanying drawings in
which:
Fig. 1 is an elevation partly in section;
Fig. 2, a plan.
a is the fixed armature of the electro-motor, mounted on the spindle b; the
spindle is mounted in the thrust-bearing c, and its inner end is by a bolt a so
attached to the body e of the whole machine as to be able to swing thereon. The
thrust-bearing c is fixed to the casing f which in its interior has the field-magnets g
of the motor and forms the magnetic field for the same. The outer end of the
casing fis formed into a rotary disc, in an annular groove whereof is mounted the
spool h of the electro-magnetic clutch. On the periphery of the casing f there are
two rings i, through which flows the current for the motor.
The current is supplied in the usual manner by sliding contact pieces touching the
rings i. From the rings i the current flows through brushes within the casing f,
to the commutator-segments 1, of the fixed armature a and to the spools of the field
magnets g.
On the spindle b turns a hollow screw spindle m having a steep pitched thread.
The inner end of the screw spindle carries by means of a spring disc a soft iron
ring o, facing the coil or spool h of the electro-magnetic clutch. The two rings j on
the periphery of the casing f, serve to supply current for the electro-magnetic
clutch.
On the screw spindle ma nut p is movable up and down and this is connected by
the arms q-which form a toggle joint-on the one hand with an arm of the body e
of the apparatus; and on the other hand with the ends of the two-armed lever t,
fulcrumed on the body at s. The said lever t t, carries the jaw u capable of oscillating
on the horizontal pin ; and the jaw u is so connected with the guide rod w attached
to the body of the apparatus as to cause its operative end to move in a straight line.
The fixed jaw x is attached to the upper arm y of the body of the apparatus.
The outer end of the spindle b is fitted with a disc, against the conical inner end
whereof bears, through conical friction rollers 2, the conical disc m¹ on the end of the
spindle m.
During operation of the apparatus the motor is in circuit and consequently the
casing with the coil or spool h rotates. To close a rivet the work operated upon,
with the red-hot rivet in place, is slipped between the two jaws u and x and the
circuit of the coil h is completed. The coil will now attract the iron armature o and
thus cause rotation of the disc n and spindle m. The nut p is by the screw-spindle m
drawn inwards, the toggle-joint qq approaches its straightened position and the
jaw u is moved towards the fixed jaw x, compressing the rivet between them. If now
the circuit of the electro-magnetic clutch is broken, the spindle m will stop and
if sufficient pressure obtains between the two jaws, the nut p is automatically pushed
back a slight distance rapidly rotating the spindle m.
As the armature o has considerable inertia and the thread of the spindle m is very
steep, an instants impulse is sufficient to withdraw the jaw w from the jaw
sufficiently far to permit the introduction of a fresh rivet.
The electro-magnetic clutch may be thrown out of operation at any instant by
hand, when however the jaw u reaches a certain position, this is effected auto-
matically. To this end an insulated conducting strip 3 is fixed on the body of the
apparatus along which travels a sliding piece 4. The latter is adjustable on a screw
spindle 5 connected with the levert by a connecting rod, 6. This contact device is
inserted in the circuit of the coil h and the current passes through this coil as long
as the sliding piece 4 touches the strip 3. At a given position of the jaw u the

page_text: sliding piece 4 however leaves the strip 3, the circuit is broken, and the magneto-
electric clutch becomes inoperative, and the rivetting jaw returns to its original
position. By altering the position of the sliding piece 4 on the screw spindle 5 the
device can be adjusted to suit rivets of various sizes.
The screw spindle m as well as the spindle may be arranged vertically in which
case the levert directly connected with the sliding nut, may be mounted on the
upper part of the body of the apparatus.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed as communicated
to me from abroad by my foreign correspondent I declare that what I claim is :-
(1) An electric rivetting machine characterized by an electro magnetic clutch
transmitting the rotary motion of the electric motor to a screw spindle which
produces motion of a nut actuating the movable jaw.
(2) In a rivetting machine such as characterized in Claim 1 the arrangement of
an electro magnetic clutch, such as h, o, consisting of a part rigidly connected with
the rotating portion of the electric motor and carrying a coil or spool of a magnet,
and a ring connected with the spindle by an elastic disc, which ring, when the coil is
excited, is attracted by the coil and then participates in the motion of the same.
(3) In a rivetting machine such as that characterized in Claim 1, the arrangement
of a sliding contact 4 adjustably connected with the lever carrying the movable
rivetting jaw, and which serves to break the circuit of the electro magnetic clutch as
soon as the movable jaw has reached a certain predetermined position.
(4) In a rivetting machine such as is characterized in Claim 1, the arrangement
of a toggle joint q which connects the nut p on the one hand with the body of the
machine or apparatus, and on the other with the lever which carries the movable jaw,
so that it operates the movable jaw when the nut p is moved on its spindle.
(5) The improved portable electrie rivetting machine herein before described with
reference to the accompanying drawings.
Dated the 9th day of January 1900