Improvements in Apparatus or Devices for Starting and Arresting Electro-motors Employed in Driving Wire-drawing or other similar Machines.
Year: 1896

page_text: Date of Application, 8th May, 1899
Complete Specification Left, 5th Feb., 1897-Accepted, 1st May, 1897
PROVISIONAL SPECIFICATION.
Improvements in Apparatus or Devices for Starting and Arresting
Electro-motors Employed in Driving Wire-drawing or other
similar Machines.
1, HENRI PIEPER fils, of Rue de Bajards, Liège in the Kingdom of Belgium,
Managing Director, do hereby declare the nature of said invention to be as
follows:-
This invention relates to means for starting and arresting wire-drawing and
other similar machines driven by electricity, the main feature of the said invention
being, that it enables the fluctuations occurring in the consumption of current by the
motor to be utilised for the purpose of causing the latter instantaneously to stop,
whenever this may be necessitated either by the breaking of a wire, or by a coil
of wire being completed, or by any other circumstances causing the wire to unwind
from the whim or reel, or by other drawbacks or inconveniences.
The electro-motor is started by means of a lever adapted in the case of metal
starting resistances to shift or move a brush or other contact, or in the case of
liquid starting resistances-to cause a metal plate to be immersed in the liquid.
When such starting resistance is fully switched out and the motor runs with a load,
the said lever is retained in the "starting" position by the armature of an electro
magnet excited by the motor current, said armature being subjected to the counter-
action of a retractor spring, or of a balancing weight. Or an arresting pawl or
catch, connected with the armature (influenced by a retractor spring) of the electro-
magnet excited by the motor current, may be employed.
When the lever is moved to such a position as to cut out the motor a metal plate
fixed to said lever, but insulated therefrom, comes into contact with binding posts;
whereby the outer circuit of the motor is opened, whilst the circuit of its armature
is kept closed across a weak resistance.
To start the motor, the lever is moved into the starting position by foot or hand,
when it is retained there by the action of said electro magnet so long as the motor
is sufficiently "loaded" and consequently receives sufficient current to enable
said magnet to overcome the action of the spring or counter-weight.
As soon, however, as the current falls below the limit deterinined by the said
spring or weight, such spring or weight, overbalancing the attraction due to the
current, causes the lever to return into its original position, and the short-circuiting
of the motor results in the manner above stated. Then the armature of the motor,
owing to its inertia, continues to run for a very short time as a generator, which
has the effect of rapidly consuming its inertia so that the machine is suddenly
arrested.
By the arrangement described the stoppage of the motor is effected automatically
immediately its load ceases, or becomes insufficient from any cause, such, for
example, as the breaking of the wire, the total exhaustion of the supply of wire,
or the completion of any other work, and thus obviates the many difficulties and
the annoyance which the idle motion of a wire-drawing or other machine is apt
to cause.
In order to avoid all the inconveniences that might arise from the electro
magnet being allowed to act when the lever is being moved into the starting

page_text: position, and to enable the electro magnet to be dispensed with in case of need, a
switch may be provided for short circuiting the same.
Dated this 8th day of May 1896.
JOHNSONS & WILLCOX,
Agents.
mprovements in Apparatus or Devices for Starting and Arresting
Electro-motors Employed in Driving Wire-drawing or other
similar Machines.
I, HENRI PIEPER fils, of Rue de Bajards, Liège in the Kingdom of Belgium,
Managing Director 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 relates to means for starting and arresting wire drawing and other
similar machines driven by electricity, the main feature of the said invention being,
that it enables the fluctuations occurring in the consumption of current by the
motor to be utilized, for the purpose of causing the latter instantaneously to stop,
whenever this is necessitated either by the breaking of a wire, or by a coil of wire
being completed, or by any other circumstances causing the wire to unwind from
the whim, or reel, or by other cause.
The electro-motor is started by means of a lever adapted, in the case of metal
starting resistances, to shift, or move, a brush, or other contact over a series of
gradually weaker resistances or-in the case of liquid starting resistances-to
cause a metal plate to be gradually immersed in the liquid to gradually diminish
the resistance formed by the latter. When such starting-resistance is fully
switched out and the motor runs with a load, the said lever is retained in the
"starting" position by the armature of an electro-magnet, excited by the motor
current, said armature being subjected to the counter action of a retractor spring,
or of a balancing weight. Or an arresting pawl or catch, connected with the
armature (influenced by a retractor spring) of the electro-magnet excited by the
motor current, may be employed.
When the lever is moved to such a position as to cut out the motor a metal plate
fixed to said lever, but insulated therefrom, comes into contact with binding posts;
whereby the outer circuit of the motor is opened, whilst the circuit of the armature
is kept closed across a weak resistance.
To start the motor, the lever is moved into the starting position by foot or hand,
when it is retained there by the action of the said electro-maguet so long as the
motor is sufficiently "loaded" and consequently receives sufficient current to enable
the said magnet to overcome the action of the spring or counter-weight.
As soon, however, as the current falls below the limit determined by the said
spring or weight, such spring or weight, overbalancing the attraction due to the
current, causes the lever to return to its original position, and the short-circuiting
of the motor results in the manner above stated. Then the armature of the motor,
owing to its inertia, continues to run for a very short time as a generator, which
has the effect of rapidly consuming its inertia so that the machine is suddenly
arrested.
By the arrangement described the stoppage of the motor is effected automatically
immediately its load ceases, or becomes insufficient from any cause, such, for
example, as the breaking of the wire the total exhaustion of the supply of wire,
or the completion of any other work, and thus obviates the many difficulties and

page_text: the aunoyance which the idle motion of a wire-drawing or any other machine is
apt to cause.
In order to avoid all the inconveniences that might arise from the electro-
magnet being allowed to act when the lever is being moved into the starting
position, and to enable the electro-magnét to be dispensed with in case of need, a
switch may be provided for short circuiting the same.
In the accompanying drawing I have diagrammatically represented an arrange-
ment according to my invention in combination with a liquid starting resistance.
a is the armature and the field magnet coil of the motor m. is the lever for
cutting in and out the liquid resistance rr. To this lever is secured the
armature a¹ of an electro-magnet e the coil e¹ of which is placed in the circuit c of
the armature a. The lever is moved into starting position against the resistance
of a counter weight or a spring w, this resistance corresponding to the allowed.
minimum load of motor m.
The circuit c of the motor armature a is from main conductor +p, across
resistance, lever 1, coil of electro magnet e and armature a to main
conductor
p.
is a switch for establishing a shunt a' around the electro-magnet e.
When the lever is held in its retracted position by the spring w, as shewn in
full lines, the metallic plate of the resistance rris removed from the liquid
and consequently the circuit c of the armature a is open. In this position of the
lever 1, a metallic lever fixed to the under side of the said lever is in contact
with a binding post or binding posts whereby the circuit e of the armature a is
closed through a conductor y in which is placed a weak resistance g.
The circuit c of the field magnet coil of motor m is so branched off from the
mains +p and -p as to be independent of the starting lever l, that is to say, the
exciting circuit e' will be maintained whether the lever I is in the starting position
or is removed therefrom.
Supposing the lever to be in the retracted or opening position as shewn in full
lines. For starting the motor first the shunt s' around electro-magnet e is
established by means of the switch a, whereby the said electro-magnet is cut out,
when the lever I is moved by hand or foot into the starting position, that is to say,
with the armature a' in contact with the core of electro-magnet e, as shewn in
dotted lines.
This shifting of the lever has the effect of dipping the metallic plate into
the liquid r, whereby the armature a of the motor m is connected with the main + p.
As the resistance of the spring w does not allow the lever to be shifted suddenly,
the dipping in of the plate r' takes place progressively so that in starting the motor
the armature a is progressively fed with current. Finally the shunt is broken
by opening the switch s, so that the electro-magnet e is placed into the circuit of
the armature d and retains the lever in the starting position by its attraction
exerted on armature a'.
The initial cutting out of the electro-magnet e is necessary from the reason that
because of its required strength, it would, if in circuit from the beginning,
suddenly attract the armature a with the effect of suddenly cutting out the liquid
resistance, so that the motor armature a would be exposed to the full voltage
prior to having speed imparted to it, and would be burned.
The lever is maintained in the working position as long as the motor mis
sufficiently loaded and consequently the current passing through the armature-
circuit c is strong enough to overcome the power of the spring or counterweight w
through the agency of the electro-magnet e. As soon, however, as the current
falls below the limit determined by the power of said spring or weight w, the latter
overcomes the attraction of the electro-magnet e and retracts the lever into its
initial position so as to withdraw plate from the liquid r, thus breaking the
connection between c and + p. By this return movement of the lever the
contact fixed thereto is caused to make contact with the posts and thus to close
the circuit of the armature a upon itself through the conductor g and the weak

page_text: resistance g. The effect of this is, that the armature a running with full speed,
acts for a very short time as a current generator whereby its inertia is rapidly
consumed.
Obviously the lever I may be maintained in working position by a catch acted
upon by the electro magnet e instead of by the direct action of the latter as
described.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, 1 declare that what
I claim is :-
A device or apparatus for starting and arresting electromotors, the starting
lever of which, when the motor is fully loaded, is retained in working position
against the resistance of a counterspring or weight by the attraction of an electro-
magnet excited by the armature circuit when the motor is fully loaded, but which
is retracted by the said spring or weight when the load diminishes and thereby
caused to close the armature circuit upon itself across a weak resistance, so that,
the exciting circuit of the motor remaining closed, the armature is caused to act as
a current generator, whereby its inertia is rapidly consumed, substantially as and
for the purpose hereinbefore specified.
Dated this 5th day of February 1897.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.