Improvements in Reciprocating Electric Motors.
Year: 1891

page_text: Date of Application, 17th June, 1891
Complete Specification Left, 12th Feb., 1892-Accepted, 2nd Apr., 1892
PROVISIONAL SPECIFICATION.
Improvements in Reciprocating Electric Motors.
I, HENRI PIEPER fils, of 12 Rue des Bayards, Liege in the Kingdom of
Belgium, Electrician, do hereby declare the nature of this invention to be as
follows:-
The electric motor forming the subject of this invention has sprung forth from
the electric regulator for which I have obtained the British Patent A.D. 1890,
No. 4000.
The said regulator substantially consists in an electro-magnet, an armature
being under the influence of both poles of the former, and a coil surrounding the
armature and located in one of the magnetic fields formed between the armature
and the electro-magnet. Besides this, the coil and the said magnetic field, which
are movable in respect to each other lengthwise to the coil, have such dimensions
that the coil is either longer or shorter than the field, and the range of motion is
so limited that the number of convolutions of the coil being in the magnetic field
will always remain the same. Under these conditions the reciprocal action of the
magnetic field and the current circulating in the coil, will generate a force tending
to produce a relative motion of the two parts, the said force being dependent
upon the strength of the current in the coil and upon that of the magnetic field or
of the current producing the same, while the force remains unvaried so long as the
said range of motion of the parts is not exceeded. The coil may be movable
independently of the armature or it may be fixed to, and movable together with
the latter.
Instead of a single coil two connected coils may be employed, located severally
in the two magnetic fields formed between the electro-magnet and the armature,
and in which coils the current circulates in opposite directions.
The nature of the present invention consists in the combination, with the
described device, of a switch arranged to be shifted either by the movable part of
the device, or by hand, or by any other means, and which serves for the
interruption and establishment or the reversal of the current in the coil of the
electro-magnet or in that of the armature. By these means a motor is obtained
for producing motion either in one direction at a time, or in alternating directions,
and which is capable of useful application for driving machine-tools, pumps, &c.
Preferably the pole-pieces of the electro-magnet are perforated and the
armature, having the coils fixed thereon, is passed through the said perforations
and arranged to move within the same. At the end of each stroke, limited by
buffers, the armature may strike against a lever connected to the switch, and
whereby the latter is shifted to reverse the current. If the armature is moved
only in one direction by electricity and in the opposite direction by any other
power, such as gravity, the switch requires only to break and establish the current.
Two or more of the described motors may be so combined that the armature of
one shifts the switch of the second, the armature of the second the switch of the
third, and so on.
For some purposes it is desirable to automatically arrest the armature at one or
both ends of its stroke. To this end I arrange opposite to the end of the armature
a pawl adapted to engage in a notch of the same. The said pawl is made of a
metal not subject to the influence of magnetism, while to the pawl is fixed an arm
of iron having such position, relatively to the armature or the electro-magnet,
that when the armature or the electro-magnet, as the case may be, is magnetised, it
will attract the iron arm and thereby cause the pawl to be disengaged. Or, the

page_text: pawl is made of iron and provided with a spring for retracting it; the magnetism
of the armature producing in this case the engagement.
In motors of great power I employ an electro-magnet with three or more pole-
pieces and an armature with a like number of coils; these coils being of course
so arranged that, when there is current, the forces resulting from the reciprocal
action of the different magnetic fields and of the armature-coils, will have all the
same direction.
The armature may consist in a straight bar having rectilinear motion, or it may
be bent to form an arc of a circle, or a full ring, oscillating on an axle, the poles of
the electro-magnet being in each case arranged accordingly.
Dated the 17th day of June 1891.
J. H. JOHNSON & Co.,
Agents.
COMPLETE SPECIFICATION.
Improvements in Reciprocating Electric Motors.
I, HENRI PIEPER fils, of 11 Rue des Bayards, Liege, in the Kingdom of
Belgium, Electrician, 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 :-
The electric motor forming the subject of this invention has sprung forth from
the electric regulator for which I have obtained the British Patent A.D. 1890,
No. 4000.
The said regulator substantially consists in an electro-magnet, an armature being
under the influence of both poles of the former and a coil (armature coil)
surrounding the armature and located in one of the magnetic fields formed
between the armature and the electro-magnet. Besides this, the armature-coil
and the said magnetic field, which are movable in respect to each other lengthwise
to the coil, have such dimensions that the coil is either longer or shorter than the
field, and the range of motion is so limited that the number of convolutions of the
coil being in the magnetic field will always remain the same. Under these
conditions the reciprocal action of the magnetic field and the current circulating
in the coil, will generate a force tending to produce a relative motion of the two
parts, the said force being dependent upon the strength of the current in the coil
and upon that of the magnetic field or of the current producing the same, while
the force remains unvaried so long as the said range of motion of the parts is not
exceeded. The coil may be movable independently of the armature, or it may be
fixed to, and movable together with the latter.
Instead of a single armature coil two connected coils may be employed, located
severally in the two magnetic fields formed between the electro-magnet and the
armature, and in which coils the current circulates in opposite directions.
The nature of the present invention consists in the combination, with the
described device, of a switch arranged to be shifted either by the movable part of
the device, or by hand, or by any other means, and which serves for the
interruption and establishment or the reversal of the current in the coil of the
electro-magnet or in that of the armature. By these means a motor is obtained
for producing motion either in one direction at a time, or in alternating directions,
and which is capable of useful application for driving machine-tools, pumps, &c.
Preferably the pole-pieces of the electro-magnet are perforated and the
armature, having the coils fixed thereon, is passed through the said perforations
and arranged to move within the same. At the end of each stroke, limited by
buffers, the armature may strike against a lever connected to the switch, and
whereby the latter is shifted to reverse the current. If the armature is moved
only in one direction by electricity, and in the opposite direction by any other
power, such as gravity, the switch requires only to break and established the

page_text: current. Two or more of the described motors may be so combined that the
armature of one shifts the switch of the second, the armature of the second
the switch of the third, and so on.
For some purposes it is desirable to automatically arrest the armature at one or
both ends of its stroke. In view hereof I arrange opposite to the end of the
armature, or in any other suitable position, a pawl adapted to engage in a notch
or with a shoulder of the same. The said pawl is made of a metal not subject
to the influence of magnetism, while to the pawl is fixed an arm of iron having
such position, relatively to the armnature or the electro-magnet, that when the
armature or the electro-magnet, as the case may be, is magnetised, it will attract
the iron arm and thereby cause the pawl to be disengaged. Or, the pawl is made
of iron and provided with a spring for retracting it; the magnetism of the
armature producing in this case the engagement.
In motors of great power I employ an electro-magnet with three or more pole-
pieces and an armature with a like number of coils; these coils being of course so
arranged that, when there is current, the forces resulting from the reciprocal action
of the different magnetic fields and of the armature-coils, will have all the same
direction.
The armature may consist in a straight bar having rectilinear motion, or it may
be bent to form an arc of a circle or a full ring, oscillating on an axle, the poles
of the electro-magnet being in each case arranged accordingly.
In the annexed drawings
Fig. 1 is a motor carried out according to my invention.
Fig. 2 shows the switch thereof with the parts in different position.
Fig. 3 represents a combination of two motors operating their switches
reciprocally.
Figs. 4 and 5 are views of motors with arresting pawls.
Fig. 6 shows a motor with straight multipolar electro-magnet and straight
armature, and Fig. 7 a motor with circular multipolar magnet and circular
armature.
Fig. 8 is a view of another arrangement of a motor with arresting-pawl.
Fig. 9 shows an electro-magnet and armature in which the former is movable.
The motor represented by Fig. 1 is composed of the electro-magnet E having
the pole-pieces PP, which are perforated, the iron bar B forming the armature,
and the two coils S S¹ surrounding the armature and fixed thereto, the said coils
being wound in opposite directions, but forming one continuous conductor. The
armature passes with the coils S S' through the perforations of the pole-pieces P P¹
of the electro-magnet and it is movable therein lengthwise. The coils S S¹ have
such length that, during the motion of the armature, which is limited by the
buffers i, the coils will always remain with the same number of convolutions in
The switch
the magnetic fields formed by the pole-pieces P P and the armature.
consists in the tongue a pivoted to the binding-post band arranged to be put in
contact with either of the binding-posts cd, the tongue a pivoted to the binding-
post and capable of contact with binding-posts cd, and the rod e connecting the
two tongues, but insulated therefrom. The post is connected to the coil of the
electro-magnet, the post c to the coil S¹, the posts d and d¹ both to the coil S, and
the post to the line-wire p, while the other line-wire, o, is led to the end of the
coil of the electro-magnet not connected with the switch. If the tongues a a¹ are
shifted to the left, as in Fig. 1, the tongue a forms communication between the
posts b and c, and the tongue a' that between the posts and d', so that the
current then takes its course from wire o through the coil of the electro-magnet
and the parts bac, passes through the coils S¹ S from right to left, and leaves the
apparatus through the parts d'a¹ l' and wire p. If, on the contrary, the tongues
are shifted to the right, as in Fig. 2, tongue a connects the posts b and d, tongue a²
the posts and c, and the current flows through the coils S S₁ in opposite
direction. The automatic shifting of the tongues a a' is brought about by means of
two levers h², against which the armature touches at the end of its course to the

page_text: right and the left, and from which motion is transmitted to the rod e by the rod g
and the lever f. If the levers h and ¹ are omitted. or brought out of reach of the
armature, the switch may be shifted by hand.
If the armature is subject to be moved in one direction by any other force than
electricity, such as gravity or spring-power, which is the case if, for instance, it is
placed with its armature vertical, it requires for its automatic motion an alternate
making and breaking of the current only.
Fig. 3 shows two of the described electro-motors connected in such manner that
the one actuates the switch of the other. In like manner three or more of these
motors may be so combined that the first one shifts the switch of the second, the
second motor the switch of the third, and so on.
One arrangement of the means for arresting the armature is shown by Fig. 4.
The same consists in two pawls k and turning on fixed pivots and adapted to
automatically engage in the notches m and m¹ cut into the armature, the latter
being secured, after interruption of the current, against accidental backward
displacement, as soon as the pawl k has dropped into notch m, or pawl k¹ into
notch m¹. For the purpose of disengaging the pawls whenever the current is
established for shifting the armature, the pawls are made of a metal not acted
upon by magnetism, and each pawl is provided respectively with iron arms and l',
which has such form that, when it is attracted by the armature magnetised by the
current, the engaged pawl will be raised so as to leave the armature free to move.
Certainly the magnetised armature will at each end of its course tend to attract
the armor, and to keep the corresponding pawl raised; but as soon as the
current is broken, the attraction ceases and the pawl drops into the notch.
Fig. 5 shows an arresting-device applied to a vertically-movable armature, and
which, contrarily to the foregoing one, sustains the armature as long as the same is
magnetic. The pawl 2 is, in this case, made of iron, and it is withdrawn by a
spring, n, after the current circulating in the coils of the armature is broken.
With this arrangement the current may, after the raising of the armature, be
diminished in strength up to the point at which, the magnetism of the armature is
just sufficient to keep the pawl in engagement.
The pawl may also be disposed to be actuated by the magnetism of the electro-
magnet, as represented by Fig. 8. For this purpose it is constituted by an arm ³
not subject to be acted upon by magnetism, and an iron arm 1³, the two arms.
forming together an elbow-lever pivoted to a bracket of non-magnetic metal on the
electro-magnet. The arm forming the pawl is brought by the spring n' into
engagement with the notch in the armature when the current, circulating around
the electro-magnet, is broken, whereas disengagement takes place when the said.
current is established and the electro-magnet attracts the arm 13.
The multipolar arrangements of the motor represented by Figs. 6 and 7, will be
understood from the foregoing without further description. By reducing the
number of poles of the field-magnet of motor Fig. 7, and that of the coils of the.
armature to two, a bipolar circular arrangement will be obtained.
In all cases the coil or coils of the electro-magnet and those of the armature.
may be placed in the same circuit or in different circuits.
While in the described arrangements the electro-magnet is stationary and the
armature movable, Fig. 9 shows a movable electro-magnet E' combined with an
armature, formed by the rods B B', magnetically connected together at their ends
by iron bars, the said rods B B' having the respective coils SS¹ wound around
them.
The switches have in Figs. 4 to 9 been omitted, as they may be alike to the one.
described with reference to Figs. 1 and 2.
If the armature is to be stationary and motion is to be imparted to the coils
only, the latter are wound on a tube placed on the armature and adapted to slide
thereon. If, on the other hand, a short coil is to be combined with a long field,
the arrangement may consist in a bar of iron placed in the centre of an iron. tube:
and magnetically connected thereto at its ends, two connected magnetising-coils.

page_text: wound in opposite directions on the end portions of the said bar, the short
armature-coil being placed movably on the bar between the magnetising-coils,
which have to be far enough apart to allow sufficient range of motion to the
armature-coil. Under these conditions the portions of the bar carrying the
magnetising-coils, form, together with the iron tube and the said magnetising-coils,
the electro-maguet, the armature is constituted by the middle portion of the bar
on which the armature-coil slides, and the magnetic field lies between the said
middle bar-portion and the surrounding portion of the iron tube opposite
thereto.
I prefer, however, to construct the motor with long coils movable in short
magnetic fields, and to fix the coils on the armature, so that the latter has to move
with the former.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
1. A reciprocating electric motor composed of an electro-magnet having two or
more poles, an armature so arranged relatively to the electro-magnet that the
latter produces together with the armature one or more magnetic fields, a coil or
coils (armature-coils) surrounding the armature and located in the said field or
fields, the armature-coil or coils being either longer or shorter than the respective
field or fields, and the armature-coil or coils and the electro-magnet being movable
relatively to each other lengthwise to the former, either with or without the
armature, means for limiting the range of said motion so that the number of
convolutions of the armature-coil or coils being in the respective magnetic field
or fields always remains the same, an electric circuit or circuits connected to the
armature-coil or coils and the magnetising-coil or coils, and a switch for making
and breaking or for reversing the current passing through the armature coil or
coils or through the magnetising coil or coils, substantially as described.
2. In combination, with the motor specified in Claim 1, means, in connection
with the movable part thereof, for shifting the switch, substantially as set forth.
3. In combination, with the motor specified in Claim 1, means for arresting the
movable part, consisting in a shoulder on the latter and a pawl capable of engaging
with the said shoulder and of being thrown into or out of engagement by a
magnetised part of the combination, substantially as described.
Dated the 12th day of February 1892.
J. H. JOHNSON & Co.,
Agents.