Improvements in and relating to the Driving and Controlling of Rivetting, Shearing, Punching, and other Machines by Electricity.
Year: 1892

page_text: Date of Application, 11th Feb., 1892
Complete Specification Left, 15th Sept., 1892-4ccepted, 29th Oct., 1892
PROVISIONAL SPECIFICATION.
Improvements in and relating to the Driving and Controlling of
Rivetting, Shearing, Punching, and other Machines by Electricity.
I, ALBERT PIAT, of 15 Rue des Halles, Paris, France, Engineer, do hereby
declare the nature of this invention to be as follows:-
This invention has for objects to impart rotary motion to the driving shafts of
machines of various kinds such as rivetting, shearing and punching machines
(hereinafter included in the term rivetting machine) and to arrest, when desired,
the motion of such shafts in a very rapid manner. For this purpose on the
driving shaft of the rivetting machine is fixed the armature of an electric motor
that is connected with any suitable source of electricity, it may be a generating
dynamo or an electric accumulator, by means of a switch of special construction.
The driving shaft according to one arrangement is connected by means of
suitable mechanism such as gear wheels with a screw actuating the piston of an
hydraulic rivetting machine. The switch comprises a lever provided with contact
pieces which are moved between circular contacts and a number of terminals
arranged concentrically to the pivot of the lever. In one position of the switch
lever the current from the electric generator (hereinafter called a dynamo) passes
through the switch to the motor armature which is thereby caused to rotate and to
the field magnets of the motor whence it returns to the dynamo.
In another position of the switch lever the dynamo is short circuited; the
current passing directly from it to the field magnets of the motor and not through
the motor armature, which act upon the armature of the motor which is thus
converted, which, assuming it to be rotating, will act after the manner of the
armature of a dynamo to generate an electric current. Thus the armature which
was driven, in the first case at a high velocity, is, by short circuiting it, converted
from a receiver of electrical energy into a generator of electrical energy requiring
the expenditure of a considerable amount of work which causes it to stop almost
immediately as if under the influence of a powerful brake. Resistances are
provided which can be inserted in the circuit between the dynamo and the motor
by placing the switch lever in positions intermediate between its extreme positions
so as to reduce the intensity of the current, for the purpose of reducing the speed
of the rivetting machine or for reducing the intensity of the excitation of the
field magnets of the motor for the purpose of regulating the braking action of
these field magnets on the motor armature and for preventing too large a current
passing through the dynamo when the same is short circuited.
The switch lever is so arranged that when in one position it causes the rotation
of the motor to take place in one direction, and when in another position it causes
the rotation to take place in the opposite direction. The braking also is effected
by bringing the switch lever back into an intermediate position (hereinafter
referred to as the central position of the lever). The braking may be effected
automatically by means of an arrangement such as that hereinafter described,
which returns the switch lever into its mid position at the desired time as for
example at the end of the travel of the rivetter.
For the purpose of effecting the instantaneous stoppage of the rivetting machine
in an automatic manner, when the rivet is crushed, the switch lever is furnished
with a hand lever designed to facilitate the operation thereof, and fixed on a
square portion of the shaft of a cylindrical box. This shaft is formed in one with
a cylinder between which and the box there slides over the internal surface of the
latter a second cylinder. The two cylinders are connected by a special spring.
In the central or stopping position of the switch lever, two abutments which

page_text: are fixed respectively to the central cylinder and to the outer cylinder, bear upon
a fixed stop. The switch lever is also furnished with a movable stop upon which
the abutments can also bear.
For movement in say a forward direction, the switch lever is moved to the left.
The movable stop then carries with it the abutment of the central cylinder and,
carrying the latter with it, whilst the outer cylinder which is kept stationary by
its abutment bearing against the fixed stop, places the spiral spring between the
two cylinders in tension so that if at a given moment the switch lever be released,
the spring will return it to its central position.
If the switch lever be moved to the right the movable stop will carry with it the
abutment of the outer cylinder and place the spring in tension in the same manner,
the central cylinder being rendered stationary by its abutment bearing against the
fixed stop.
Then if the switch lever be released, the spring will again bring it back into
its central or zero position as before.
For ensuring the position of the switch lever, and for effecting its return in an
automatic manner to the central or zero position, an axle is mounted upon the base
plate of the switch upon which axle is keyed a double or two part lever. On
the said axle there is fixed an arm connected to a bar on which is mounted a handle
the position of which on the bar can be varied and which can be fixed by means
of a screw. This bar which is provided at its end with a nut forming a stop, slides
in a socket or tappet fixed on the piston of the rivetting machine and which, in
moving with the piston, comes alternately in contact with the handle and the nut
at the end of the bar.
To place the machine in operation the switch lever is brought into its extreme
position and the piston moves say from right to left. During this movement a pin
or projection fixed on a prolongation of the switch lever is brought into a notch
formed in one arm of the double lever above referred to, so as to retain the
switch lever in the position into which it has been moved. When the tappet
attached to the piston of the rivetting machine meets the handle it carries with it
the bar to which the handle is secured, and operating the attached arm and double
lever so as to release the switch lever which is immediately returned to its central
or zero position by the spiral spring and thereby causing the piston of the rivetting
machine to at once stop.
In order to cause the piston to make its return stroke the switch lever is brought
into its opposite position, but as there is no necessity for the piston to move as fast
during its return stroke as during its forward stroke, it is sufficient to engage the
switch lever in a notch in the other part of the double lever, situated nearer to
the zero position than the other notch. By this means the piston is caused to make
its return movement at a slower speed than its forward movement. The piston is
stopped in its return movement when the tappet on the piston meets the nut on
the end of the bar, at which time the switch lever is again disengaged as before
and returned to its central or zero position and the piston stopped. Each part of
the double lever is or may be mounted on a shaft provided with a catch so
arranged that when the shaft rotates it carries with it the parts of the double
lever only in the direction which causes the disengagement of the switch lever.
In order to prevent the piston or other part restarting in the same direction as
before, after it has been arrested in the manner described there are pivotted on
the base plate of the switch two bolts or locking devices that are connected to the
parts of the double levers by springs. These bolts are arranged in such a manner
that when in consequence of the angular movement of the double lever the pin or
projection at the end of the switch lever is engaged with one of the parts of the
said lever, the corresponding bolt will place itself across the path taken by the pin
or projection in such a way as to allow the said pin or projection to return to its
central or zero position, but by immediately reassuming its original position, will
prevent the pin or projection returning to the position from which it was
automatically released. It will then be necessary to engage the switch lever in

page_text: the notch in the other part of the double lever in order to replace the said bolt in
position and to arrest the movement of the bolt on the other part of the double
Jever.
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2
LAAA
A. PIAT,
By L. W., per F. B.
COMPLETE SPECIFICATION.
Improvements in and relating to the Driving and Controlling of
Rivetting, Shearing, Punching, and other Machines by Electricity.
I, ALBERT PIAT, of 15 Rue des Halles Paris, France, 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:
This invention has for object to impart rotary motion to machines of various
kinds such as rivetting, shearing and punching machines (hereinafter included in
the term rivetting machine) and to enable the motion of said machines to be
arrested in a very rapid manner at the required times.
For this purpose on the driving shaft of the rivetting machine (which, for
example may be a hydraulic rivetting machine of the Piat and Delaloe system) is
fixed to the armature of an electric motor that is connected by means of a switch
of special construction, with any suitable source of electricity, such as a generating
dynamo or an electric accumulator.
In the accompanying drawings,
Fig. 1. is a diagrammatic view showing the general arrangement of apparatus
according to this invention.
a is the armature shaft of an electric motor.
It is connected by means of suitable mechanism such as gear wheels with a
screw that actuates the piston or plunger of the rivetting machine.
KK represent the field magnet coils of the motor and 66 the commutator
brushes.
The switch which is shown within the dotted lines A, comprises a lever B
provided with contact pieces C' C¹ arranged to move between circular contacts D
F, F¹ and a number of terminals arranged concentrically to the axis of the
lever.
With this arrangement if the switch lever be moved into the position indicated
by the letter B the current from the electric generator G (hereinafter called
the dynamo) will pass by the wire 1, 2, the corresponding terminal d, the piece C
of the lever contact F the wire 3 and brush b, to the motor armature E which
will thereby be caused to rotate. The current will return through the other brush b.
the wire 4 contact F', the contact piece C¹ of the lever contact D and wire 5
to the field magnet coils K whence it will pass to the other pole of the dynamo by
the wire 6. If the switch lever be moved into the position indicated by the letter B¹
the dynamo will be short circuited past the motor armature, the current passing
from one pole of the dynamo direct to the field magnet coils K by the wire 1. 2.
resistances R, lever contact C and contact D, and returning from the coils K as
before by the wire 6.
Thus the motor armature which in the first position of the switch lever will be
driven at a high velocity, will by moving the switch lever into the second position
be converted from a receiver of electrical energy into a generator of electrical
energy, with the result that it will be almost immediately brought to rest as if under
he influence of a powerful brake.
.
As will be seen the resistances are so arranged that by placing the switch lever
n positions between the positions B and B the strength of the dynamo current,
can be reduced for the purpose of reducing the speed of the rivetting machine, or.

page_text: for reducing the excitation of the field magnet coils K can also be varied for the
purpose of regulating the braking action of the field magnets on the motor armature
and for preventing too large a current passing through the dynamo when the motor
armature is cut out of circuit.
It will be obvious that if the motor is caused to revolve in one direction when
the switch lever is in position B, it will revolve in the opposite direction if the
lever be moved beyond its mid or central position B' into some position B", the
motor being brought to rest when moved from either of the positions B B¹¹ to
the central position B'.
The motor armature may be brought to rest automatically by suitable mechanism
such as that hereinafter described, which returns the switch lever into its mid
position at the desired times as for example at the end of the travel of the
rivetter.
Figs. 2, 3 and 4 are cross sections, and Fig. 5 a plan of part of a hydraulic
rivetting machine of the Piat type adapted to be driven and controlled according
to this invention.
Fig. 6 is a side elevation of the switch, and
Figs. 7 7 and 8 are sectional detail views of one of the carbon contacts carried
by the switch lever.
P is part of the piston or plunger of the hydraulic rivetting machine. It is
provided with a screw thread V and is actuated by a nut that is mounted to rotate
upon the screw thread portion of the piston but not to move endways and which is
operated from the shaft of the motor armature through suitable intermediate gearing
not shown.
For the purpose of effecting the practically instantaneous stoppage of the rivetting
machine in an automatic manner when a rivet is closed or headed the following
arrangement is adopted. The switch lever B which is furnished with a hand lever L
designed to facilitate its operation by hand when necessary is fixed to a shaft H
upon which a cylindrical box is mounted so as to be capable of partly turning
thereon.
This shaft H forms the axis of a freely mounted cylinder J between which and
the box I there is a second cylinder J¹ that fits the inner surface of the box I. The
two cylinders are connected by a spiral spring K*.
m m³ are two projections fixed to the cylinders J and J' respectively, and M is a
fixed stop or abutment against the two ends of which the projections m m³ bear
when the switch lever is in its central position. N is an arm of approximately.
Tshape fixed to the shaft H and thus connected with the switch lever and the ends
of which are adapted to act against the projection m or m¹ according to the direction
in which it is turned.
For causing the motor armature to rotate in a forward direction, the switch lever
together with the arm N is moved say to the left in the direction of the arrow
Fig. 3. The arm N will then act against the projection m and partly rotate the
cylinder J, the cylinder J' being meanwhile held stationary by reason of its
projection m bearing against the fixed abutment M. As a result the spiral spring K⭑
will be placed in tension and if at a given moment, the switch lever be released,
the spring will automatically return it to its central position.
If the switch lever be moved in the opposite direction or to the right the arm N
will act against the projection m¹ and partly rotate the cylinder J and place the
spring K again in tension, the cylinder J being then held stationary by reason of
its projection m bearing against the other end of the abutment M. If the switch
lever be again released, the spring K* will again return it to its central position as
before.
For fixing the switch lever in the position into which it is moved by hand, and
for effecting its return in an automatic inanner at the desired time to the central-
position the following arrangement is employed. Upon the base plate of the switch
is mounted an axle upon which is mounted two arms il. To the axle is fixed
an arm R*.connected to a rod S on which is mounted a handle T the position of

page_text: which on the bar can be varied, and which can be fixed by means of a screw as
shown. This rod S, which is provided at its end with one or more nuts T₁ that
form an adjustable stop, slides in a socket or tappet fixed on the piston P and
which, in moving with the piston, comes alternately in contact with the handle T
and the stop T
To put the rivetting machine in operation, the switch lever B is moved into its
extreme position Z whereby the piston P will be caused to move say from right to
left. By this movement of the switch lever B a pin U fixed on a prolongation of
the said lever will be caused to enter a notch * formed in the arm so that the
switch lever will be retained in the position into which it has been moved. When
however the tappet carried by the piston P comes into contact with the handle T,
the rod S will be moved to the right and will operate the arm R* and arm / so as
to disengage the pin U from the notch * and release the switch lever which will
then be immediately returned to its central position by the spiral spring K*
(Figs. 23 and 4). The motor armature will thus be brought to rest in the
manner hereinbefore explained and will consequently cause the piston P to at once
stop.
In order to cause the piston to make its return stroke the switch lever B is
moved by its handle L into its opposite position V, but as there is no necessity
for the piston to move as fast during its return stroke as during its forward
stroke it is sufficient to engage the switch lever in a notch /* in the other arm ¹
situated nearer to the zero position than the notch in the arm l. By this means
the piston is caused to make its return movement at a slower speed than its
forward movement. The piston is stopped in its return movement when the
tappet V meets the nut or stop T¹ on the end of the bar S at which time the
switch lever B will be again released and returned to its central or zero position
thereby again stopping piston P.
Each arm of the lever is or may be mounted on a shaft provided with a
catch so arranged that when the shaft rotates it carries with it the parts of the
double lever only in the direction which causes the disengagement of the switch
lever (Fig. 8).
The journalled end of each of the arms is provided with a projection
(Fig. 8) so arranged in relation to a projection on the axle Q that when the
latter is partly rotated by the lever arm R*, the one or other arm will be moved
thereby only in a direction to disengage it from the pin on the switch lever B, the
return movement being effected by a spring 1.
In order to prevent the piston P or other part restarting in the same direction
as before after it has been arrested in the manner described there are pivoted on
the base plate of the switch two bars that are connected to the arm 11
respectively by springs r, r. These bars are arranged as shown so that when in
consequence of the angular movement of one or other of the arms 11 the pin
or projection U has become engaged with one of the said arms the corresponding
bar or will place itself across the path taken by the pin or projection
in such a way as to allow the said pin or projection to return to its central or zero
position, but by immediately re-assuming its original position, will prevent the
pin or projection returning to the position from which it was automatically released.
It will then be necessary to engage the switch lever B in the notch of the other
armor in order to replace the said bar in position and to arrest the move-
ment of the bar on the other arm.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :--
1. The combination with a rivetting, shearing or other machine of an electric
motor, an electric generator, a switch and circuit connections, the arrangement
being such that when the switch lever is moved from its central or normal position
the motor and the machine connected therewith will be set in motion and when

page_text: the said lever is returned to its normal position the motor armature will be cut out
of the circuit of the electric generator and will be quickly brought to rest by the
braking action of the magnetic field of the motor substantially in the manner
herein before described with reference to Fig. 1 of the drawings annexed.
2. The combination with the apparatus referred to in the preceding claim, of
rotary bodies such as the cylinders J J' connected by a spring and each provided
with a projection arranged to normally bear against a fixed abutment, an arm fixed
to the switch lever and adapted to act against one or other of the projections
according to the direction in which the switch lever is turned, a rod such as S
arranged to be operated by a tappet on a moving part of the rivetting or other
machine, and stops for holding the switch lever, the arrangement being such that
when the switch lever is moved from its central position it will put the said spring
in tension and will become locked in its new position by one or other of the stops,
and when the rod S is operated by the said tappet, the switch lever will be released
from the stop by which it was held and will be automatically returned to its normal
position by the action of the spring substantially as described for the purpose
specified.
3. In apparatus of the kind referred to in Claim 1, the combination with the
switch lever and the arms, of the pivotted bars z, z constructed arranged and
operating substantially as described and shown for the purpose specified.
Dated this 15th dow of Cantomha. 1900
W. Lloyd Wise,
Per F. J. Brougham,
46, Lincoln's Inn Fields, London, W.Č., Agent for the Applicant.