AN IMPROVED APPARATUS FOR TRANSFORMING ELECTRIC CURRENTS
Year: 1883

page_text: LETTERS PATENT to Marcel Deprez of Boulevard Saint Denis 1 at: Paris,
Electrician Engineer for an Invention of AN IMPROVED APPARATUS FOR
TRANSFORMING ELECTRIC CURRENTS
PROVISIONAL SPECIFICATION left by the said Marcel Deprez at the Office
of the Commissioners of Patents on the 6th April 1883.
MARCEL DEPREZ of Boulevard Saint Denis 1 at Paris, Electrician Engineer
"AN IMPROVED APPARATUS FOR TRANSFORMING ELECTRIC CURRENTS
"
If one has at command an electric current of little intensity and of high tension,
it is of advantage for certain purposes to utilize the energy which it represents in
the form of another current of greater intensity and of lower tension. The inverse
case may likewise present itself. I propose to employ for this transformation
secondary piles, accumulators, condensers, and generally apparatus capable of
storing electricity.
My invention consists in forming with the accumulators a continuous transforming
apparatus receiving the current in one form and giving it off at the same time in
another deterinined form with the least possible loss of energy. For this purpose I
place on the generator current a suitable number of elements of some accumulator
arranged either in a single series or in several parallel series supplied in derivation.
In a system of this kind by arranging the branching points of a derivation in
such manner that they comprise between them a determined group of elements in
tension, the current will be produced in this derivation by virtue of an electro
motive force equal to that of the elements of the accumulator thus put into play,
increased only to an unimportant amount arising from the derivation of the
generator current. This derived current will therefore be of as low a tension as
is desired and its intensity depending only upon the resistance of its circuit will
be arbitrarily determined. But its duration will only be the time employed in
discharging the accumulator elements put into action; these having been discharged
it will be necessary to pass to another group and we will thus have a continuous
current under the single condition that the elements shall have time to be
1

page_text: recharged before they are again put into action. The derivation will therefore be
practically operated by means of two movable contacts comprising between them
a certain nuinber of accumulator elements, these contacts having a movement which
is either continuous or regularly intermittent and travelling over the series of the
poles of the accumulators with a suitable speed.
This apparatus can be employed in the inverse sense as I have already mentioned,
that is to say, the generator current can be introduced by the revolving brushes
while the useful current is taken from the whole of the elements; in this case the
transformation will be inverse, that is to say, that having a quantity current a
tension current will be collected.
The combination of these arrangements makes of the accumulator a simultaneous
transformer of the current, which is a new result.
Among the practicable arrangements for carrying out my invention I will
describe the following by way of example.
As the accumulator does not require a large storage capacity seeing that it is
intended to be constantly discharged it can be reduced to very small dimensions.
I propose to employ secondary piles analogous to those of M. Planté, but composed
simply of small sheets of lead adherent to the two faces of sheets of paper
impregnated with paraffin or of other insulating material and electrically connected.
The plates thus formed are placed like very narrow partitions in a vessel of suitable
form, or they may be juxtaposed and separated by small insulating frames so as
to constitute a series of tight cells; the cells thus formed are filled with acidulated
.water; the secondary pile element will thus be composed of two lead plates placed
opposite each other in the same cell. By means of lugs or projections on each
sheet all the positive poles are at one side and all the negative poles at the other.
We thus have, in a small compass, a sufficient number of elements to give as high
an electro motive force as is necessary.
For the movable contacts I adopt the following arrangement. The accumulator
elements being divided into groups representing the electro motive force which it
is required to use, the positive poles of these groups are led to a fixed insulating
disc, and each of the poles at the circumference is in the form of a metal pieco
shaped like a ratchet tooth, so that the whole will be in the form of a ratchet
wheel, each tooth of which insulated from the others receives a positive pole. A
similar disc likewise fixed receives the negative poles. Two metal pauls electrically
insulated but keyed on the same axle bear upon the teeth of these wheels where
they receive the current; these pauls are moved by the central axle which is
itself actuated by a suitable motor such for example as a Foucault electric
interrupter worked by some local pile or a derivation from the general pile. This
interrupter comprises the employment of an electro magnet the armature of which
breaks the current when it is attracted. A weight regulates by its inertia the
time of the movements of the armature. In my apparatus the movable armature
acts through the intermediation of a paul upon a ratchet wheel fixed on the
central axle. The arrangement of metal pauls thus advances one tooth on each
wheel at determined intervals so as to pass from one group of elements to the next
following. Each of the pauls also carries a spring rubber bearing upon a fixed
central piece where the current is taken. The duration of the fall of the paul
will be very slight; the interruption at the passage from one group of elements to
the next will therefore be unimportant.
The improved apparatus is specially applicable to the general distribution of
electricity

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Marcel Deprez in the Great Seal Patent Office on the 27th
September 1883.
MARCEL DEPREZ of Boulevard Saint Denis 1 at Paris Electrician Engineer
"AN IMPROVED APPARATUS FOR TRANSFORMING ELECTRIC CURRENTS »
If one has at command an electric current of little intensity and of high tension,
it is of advantage for certain purposes to utilize the energy which it represents in
the form of another current of greater intensity and of lower tension. The inverse
case may likewise present itself. I propose to employ for this transformation
secondary piles or batteries, accumulators, condensers, and generally apparatus
capable of storing electricity.
My invention consists in forming with the accumulators a continuous trans-
forming apparatus, receiving the current in one form and giving it off at the same
time in another determined form, with the least possible loss of energy. For this
purposo I place on the generator current a suitable number of elements of some
accumulator arranged either in a single series or in several parallel series supplied
in derivation. In a system of this kind by arranging the branching points of a
derivation in such manner that they comprise between them a determined group of
elements in tension, the current will be produced in this derivation by virtue of an
electro motive force equal to that of the elements of the accumulator thus put into
play, increased only to an unimportant amount arising from the derivation of the
generator current. This derived current will therefore be of as low a tension as is
desired, and its intensity depending only upon the resistance of its circuit will be
arbitrarily determined. But its duration will only be the time employed in
discharging the accumulator elements put into action, these having been discharged
it will be necessary to pass to another group and we will thus have a continuous
current under the single condition that the elements shall have time to be
recharged before they are again put into action. The derivation will therefore bo
practically operated by means of two movable contacts comprising between them a
certain number of accumulator elements, these contacts having a movement which
is either continuous or regularly intermittent and travelling over the series of the
poles of the accumulators with a suitable speed.
This apparatus can be employed in the inverse sense as I have already mentioned,
that is to say the generator current can be introduced by tho revolving brushes
while the useful current is taken from the whole of the elements; in this case the
transformation will be inverse that is to say that having a quantity current a
tension current will be collected.
The combination of these arrangements makes of the accumulator a simultaneous
transformer of the current which is a new result.
Among the practicable arrangements for carrying out my invention I will
describe the following by way of example, see Figures 1, 2 and 3 of the annexed
drawings.
As the accumulator does not require a large storage capacity seeing that it is
intended to be constantly discharged, it can be reduced to very small dimensions.
I propose to employ secondary piles or batteries analogous to those of M. Planté,
but composed simply of small sheets of lead a a adherent to the two faces of sheets
of paper 6 impregnated with paraffin or of other insulating material and electrically
connected by the pieces c c. The plates thus formed are placed like very narrow
b

page_text: -
partitions in a vessel of suitable form or they may be juxtaposed and separated by
small insulating frames so as to constitute a series of tight cells; the cells thus
formed are filled with acidulated water, the secondary battery element will thus be
composed of two lead plates a a placed opposite each other in the same cell. By
means of lugs or projections d d on each sheet all the positive poles are at one side
and all the negative poles at the other. We thus have, in a small compass, a
sufficient number of elements to give as high an electro motive force as is
necessary.
For the movable contacts I adopt the following arrangement, see Figures 4 and 5.
The accumulator elements being divided into groups representing the electro
motive force which it is required to use, the positive poles of these groups are led
to a fixed insulating disc D and each of the poles at the circumference is in the
form of a metal piece e, shaped like a ratchet tooth, so that the whole will be in the
form of a ratchet wheel, each tooth of which insulated from the others receives a
positive pole. A similar disc D¹ likewise fixed receives the negative poles. Two
metal pawls ff electrically insulated but keyed on the same axle g, bear upon the
teeth of these wheels where they receive the current; these pawls are moved by
the central axle g which is itself actuated by a suitable motor, such for example as
a Foucault electric interrupter worked by some local battery or pile or a derivation
from the general battery or pile. This interrupter comprises the employment of an
electro magnet E the armature h of which breaks the current when it is attracted.
A weight & regulates by its inertia the time of the movements of the armature.
In my apparatus the movable armature acts through the intermediation of a
pawl upon a ratchet wheel r fixed on the axle g. The arrangement of metal
pawls thus advances one tooth on each wheel at determined intervals so as to pass
from one group of elements to the next following. Each of the pawls also carries
a spring rubber m bearing upon a fixed central piece n where the current is taken.
The duration of the fall of the pawl will be very slight, the interruption at the
passage from one group of elements to the next will therefore be unimportant.
The improved apparatus is specially applicable to the general distribution of
electricity.
Having now described the nature of my said invention and in what manner the
same is to be performed I declare that I claim :—
First-The employment of apparatus capable of storing electricity such as
secondary piles or batteries, accumulators and condensers for the purpose of
transforming electric currents, that is to say as apparatus for receiving a current of
a certain tension and of a certain intensity and giving off at the same time the
same energy (except unavoidable loss) in the form of a current of different tension
and different intensity as hereinbefore set forth.
Second-The employment in apparatus for transforming electric currents in the
manner herein referred to of contacts comprising between them a certain number of
accumulator elements and passing successively from one group to another so as to
form a movable derivation traversed by a continuous current or a current
assimilable to a continuous one as herein before set forth.
Third-The employment in apparatus for transforming electric currents in the
manner herein referred to of secondary piles or batteries of very small size having
only a small storage capacity as hereinbefore described and represented in
Figures 1, 2 and 3.
Fourth The employment in apparatus for transforming electric currents in the
manner herein referred to of movable contacts passing with a continuous and rapid
movement over the conducting keys, communicating with the poles of the
accumulator elements and presenting a continuous surface so as to form the points
of departure of the derived current as hereinbefore described.
Fifth-The employment in apparatus for transforming electric currents in the
manner herein referred to of contacts turning on insulated toothed wheels as
represented in Figures 4 and 5 and passing from one group of elements to another

page_text: by a quick fall which reduces to a minimum the duration of the interruption as
herein before described.
In witness whereof I the said Marcel Deprez have hereunto set my hand and
seal this twenty fifth day of September in the year of our Lord One thousand
eight hundred and eighty three.
Witness:
ALBERT CAHEN
"
Civil Engineer
of Boulevard Saint Denis 1
at Paris
MARCEL DEPREZ (L.S.)